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  • 1985-1989  (4,730)
  • 1988  (4,730)
  • Polymer and Materials Science  (3,199)
  • Cell & Developmental Biology  (1,394)
  • Physical Chemistry  (137)
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Material
Years
  • 1985-1989  (4,730)
Year
Keywords
  • 1
    Electronic Resource
    Electronic Resource
    Immunolocalization of muscle and nonmuscle isoforms of actin in myogenic cells and adult skeletal muscle (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 9 (1988), S. 337-348 
    Details
    ISSN: 0886-1544
    Keywords: isoactins ; immunogold ; myofibrils ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: In vertebrate skeletal muscle, the proliferating myoblasts synthesize nonmuscle isoforms of actin, and the cells begin to express muscle-specific actin isoforms during their myogenic differentiation. To study the distributions of the actin isoforms in myogenic cells and fully differentiated skeletal muscle, we prepared a peptide antibody specific for the skeletal α isoform of actin and used this antibody along with an antibody specifically reactive with nonmuscle γ actin to stain cultured myotubes and adult skeletal myofibrils by double-indirect immunofluorescence. At this level of resolution, no differences in isoform localization were seen: Both muscle and nonmuscle actins were detected in the myotubes and in the striations of mature myofibrils. Myotubes were also double-stained using immunogold electron microscopy, and the isoform distributions were determined quantitatively by counting the two sizes of gold particles that corresponded to labeling with each antibody. A quantitative analysis of immunoreactivity revealed that, although both forms were present in all actin-containing structures, nonmuscle actin was relatively more prevalent along the edges (cortical microfilaments) of the myotubes, whereas the muscle isoform predominated in the interior regions (containing forming myofibrils). Thus, we have found evidence of a heterogeneous distribution of muscle and nonmuscle actin isoforms in differentiating myogenic cells, and we have demonstrated that a nonmuscle actin isoform is a component of the muscle contractile apparatus.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970090406
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  • 2
    Electronic Resource
    Electronic Resource
    Micromanipulation studies of the mitotic apparatus in sand dollar eggs (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 10 (1988), S. 172-184 
    Details
    ISSN: 0886-1544
    Keywords: chromosome movement ; spindle elongation ; micromanipulation ; mechanical properties ; mitosis ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Mechanical properties of the mitotic spindle and the effects of various operations of the mitotic apparatus on the chromosome movement and spindle elongation were investigated in fertilized eggs and blastomeres of the sand dollar, Clypeaster japonicus. On the basis of results with mechanical stretching and compression of the spindle with a pair of microneedles and the behavior of an oil drop microinjected into the spindle, it was concluded that the equatorial region of the spindle is mechanically weaker than the half-spindle region. Anaphase chromosome movement occurred in the spindle from which an aster had been removed or separated with its polar end and in the spindle in which the interzonal region had been removed. This fact indicates that chromosomes move poleward in anaphase by forces generated near the kinetochores in the half-spindle. Because of the effects of separation or removal of an aster from the spindle on the spindle elongation in anaphase and the behavior of the aster, it was concluded that the spindle elongation in anaphase is caused by pulling forces generated by asters attached to the ends of the spindle.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970100122
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  • 3
    Electronic Resource
    Electronic Resource
    Dynamics of the endoplasmic reticulum in living onion epidermal cells in relation to microtubules, microfilaments, and intracellular particle movement (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 10 (1988), S. 153-163 
    Details
    ISSN: 0886-1544
    Keywords: intracellular particle motions ; cytoplasmic streaming ; onion (Allium) epidermal cells ; video microscopy ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The endoplasmic reticulum (ER) and associated organelle and particle movements in onion (Allium cepa) bulb scale epidermal cells were observed, recorded, and analyzed using computer-assisted video (AVEC-DIC, AVEC-POL and fluorescence) microscopy. The ER is composed of two interconnected sets of filamentous membrane tubules with diameters ranging from 0.1 to 0.5 μm. The first form a more stable, stationary network of intersecting polygonal membrane tubules lying closely appressed to the plasma membrane and continuous with a second very dynamic set of longer membrane tubules that often are located parallel to each other, shifting rapidly around the cytoplasm and forming dynamic knots or organization centers. The ER, mitochondria, and spherosomes fluoresced upon chlortetracycline treatment and are therefore presumed to sequester calcium. ER and mitochrondria also stain with the fluorescent dye, rhodamine 123. Mitochrondria and spherosomes are seen to move in the cytoplasm only along paths parallel to the axis of the ER tubules. Smaller particles (0.5 μm) tend to follow these same paths but may occasionally move independently. Particles and organelles move in close, but not in direct, association with the ER tubules. In optically favored cells, actin filaments were occasionally recorded located in parallel with the ER tubules and directly associated with moving particles. Streaming ceased promptly and reversibly upon treatment with cytochalasin B, which did not visibly disrupt the ER. Short-term treatment with colchicine did not inhibit streaming or disrupt the ER network, whereas long-term (hours) colchicine treatments caused the disappearance of the stationary, cortical polygonal networks and an aggregation of still slowly moving organelles and particles onto now visible actin filaments. This suggests that microtubule breakdown disrupts the three-dimensional distribution of the ER and rearranges actin filaments in the cell's cytoplasm. Actin filaments must be directly involved in generation of movement of the particles and organelles. A three-dimensional model, based on optical sectioning of the epidermal cells, is proposed to illustrate the distribution of the endoplasmic reticulum in onion epidermal cell cytoplasm.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970100120
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  • 4
    Electronic Resource
    Electronic Resource
    Microtubule dynamics in the chromosomal spindle fiber: Analysis by fluorescence and high-resolution polarization microscopy (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 10 (1988), S. 185-196 
    Details
    ISSN: 0886-1544
    Keywords: mitosis ; kinetochore ; video microscopy ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: We describe preliminary results from two studies exploring the dynamics of microtubule assembly and organization within chromosomal spindle fibers. In the first study, we microinjected fluorescently labeled tubulin into mitotic PtK1 cells and measured fluorescence redistribution after photobleaching (FRAP) to determine the assembly dynamics of the microtubules within the chromosomal fibers in metaphase cells depleted of nonkinetochore microtubules by cooling to 23-24°C. FRAP measurements showed that the tubulin throughout at least 72% of the microtubules within the chromosomal fibers exchanges with the cellular tubulin pool with a half-time of 77 sec. There was no observable poleward flux of subunits. If the assembly of the kinetochore microtubules is governed by dynamic instability, our results indicate that the half-life of microtubule attachment to the kinetochore is less than several min at 23-24°C.In the second study, we used high-resolution polarization microscopy to observe microtubule dynamics during mitosis in newt lung epithelial cells. We obtained evidence from 150-nm-thick optical sections that microtubules throughout the spindle laterally associate for several sec into “rods” composed of a few microtubules. These transient lateral associations between microtubules appeared to produce the clustering of nonkinetochore and kinetochore microtubules into the chromosomal fibers. Our results indicate that the chromosomal fiber is a dynamic structure, because microtubule assembly is transient, lateral interactions between microtubules are transient, and the attachment of the kinetochores to microtubules may also be transient.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970100123
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  • 5
    Electronic Resource
    Electronic Resource
    Detection of single fluorescent microtubules and methods for determining their dynamics in living cells (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 10 (1988), S. 237-245 
    Details
    ISSN: 0886-1544
    Keywords: video microscopy ; digital image processing ; fluorescence photobleaching ; microtubule dynamics ; living cell dynamics ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The ability to tag biological molecules fluorescently and to detect their distribution in living cells has promoted the study of cytoplasmic organization in general and microtubule dynamics in particular. The techniques that we have selected and developed allowed the determination of spatial and temporal changes of the microtubule network in living fibroblasts at the level of individual microtubules. We have employed two general approaches for determining pattern changes: direct video microscopy and photobleaching and subsequent observation. Direct observation of fluorescent microtubules by high-definition video microscopy provided good spatial resolution at several time points, but was limited to the less congested and thinner periphery of the cell. This approach was made possible by a relatively bright, photostable reporter, xrhodamine-tubulin, and showed that microtubules underwent rounds of assembly and disassembly from their ends. Bleaching and subsequent observation of lysed cells improved the signal to noise ratio by extracting soluble chromophore and permitted observations in congested areas, but was limited to a single time interval. This approach demonstrated that microtubule domains were replaced one by one and that turnover was most rapid at the cell periphery. Antibodies specific for nonbleached chromophore can be used to enhance the signal to noise ratio further or to extend spatial resolution by the use of immunoelectron microscopy. Direct video microscopy and photo-bleaching are two approaches to the study of dynamics that have complementary strengths and wide application to the biology of living cells.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970100128
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  • 6
    Electronic Resource
    Electronic Resource
    Vesikin, a vesicle associated ATPase from squid axoplasm and optic lobe, has characteristics in common with vertebrate brain MAP 1 and MAP 2 (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 10 (1988), S. 246-254 
    Details
    ISSN: 0886-1544
    Keywords: axoplasmic transport ; motility ; microtubules ; MAPs ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Vesikin, a protein that can associate with squid axoplasmic vesicles or optic lobe microtubuies, has been implicated as a force-generating molecule involved in microtubule-dependent vesicle transport [Gilbert and Sloboda, 1986, 1988]. Because vesikin crossreacts with an antibody to porcine brain microtubule associated protein 2 (MAP 2), studies were conducted to compare squid vesikin and brain MAPs. When taxol stabilized microtubules containing vesikin as a microtubule associated protein were incubated in the presence of ATP, vesikin dissociated from the microtubule subunit lattice. This behavior would be expected for an ATP-dependent, force generating molecule that serves as a crossbridge between vesicles and microtubules. When chick brain microtubules were treated under the same conditions, MAP 2 remained bound to the microtubules while MAP 1 dissociated in a manner similar to vesikin. One dimensional peptide mapping procedures revealed that, although digestion of vesikin and MAP 2 generated several peptides common to both proteins, vesikin and MAP 2 are clearly not identical. Furthermore, the addition of vesikin or MAPS 1 and 2 to purified tubulin stimulated microtubule assembly in a manner dependent on the concentration of added protein. These findings demonstrate that brain MAPs share characteristics common to squid vesikin and support the suggestion that brain MAPs 1 and 2 might act as a force generating complex for vesicle transport in higher organisms.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970100129
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  • 7
    Electronic Resource
    Electronic Resource
    Microtubule-associated organelle and vesicle transport in fibroblasts (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 10 (1988), S. 255-262 
    Details
    ISSN: 0886-1544
    Keywords: regulation of organelle transport ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Allen Video-enhanced constrast/differential interference constrast (AVEC-DIC) microscopy was used in conjunction with video intensification immunofluorescence microscopy to demonstrate that organelles and vesicle (particles) can move in either direction along microtubular linear elements in fibroblasts [Hayden et al., 1983]. Since it is not possible to determine the number of microtubules making up a linear element with light microscopy alone, AVEC-DIC microscopy was used in conjunction with whole-mount electron microscopy to show bidirectional transport along a single microtubule [Hayden and Allen, 1984]. These studies demonstrate that the structural polarity of the microtubule does not determine the direction of particle motion, and since dynein is an asymetric molecule, a simple microtubule-dynein-particle hypothesis cannot explain bidirectional transport along a single microtubule.Very little is known about regulation of particle transport in most cell types. Human embryonic lung fibroblasts grown on glass coverslips were serum-deprived for 24 hours and re-fed with serumless medium; the particle translocations/5 minutes were then determined The cells were then re-fed with either serumless medium, serum-containing medium, or serumless medium containing some bioactive factor, and the particle translocations/5 minutes were again determined for the same cells. Medium containing 10% fetal bovine serum inhibited particle translocation by 51.8%. Of the bioactive factors tested, only vasopressin produced a significant reduction in particle translocations (38%). This suggests that protein kinase C or calcium/calmodulin kinase could be involved in regulating particle transport.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970100130
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  • 8
    Electronic Resource
    Electronic Resource
    Dynein as a microtubule translocator in ciliary motility: Current studies of arm structure and activity pattern (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 10 (1988), S. 263-270 
    Details
    ISSN: 0886-1544
    Keywords: cilia ; axoneme ; ATP-induced microtubule sliding ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The dynein arms of ciliary doublet microtubules cause adjacent axonemal doublets to slide apart with fixed polarity. This suggests that there is a unique mechanochemistry to the dynein arm with unidirectional force generation in all active arms and also that not all arms are active at once during a ciliary beat. Negative stain and thin-section images of arms in axonemes treated with β, γ methylene adenosine triphosphate (AMP-PCP) show a consistent subunit construction where the globular head of the arm interacts with subfiber B of doublet N + 1. This interpretation differs from that provided by freeze etch and STEM interpretations of in situ arm construction and has implications for the mechanochemical cycle of the arm. A computer model of the arms in relation to other axonemal structures has been constructed to test these interpretations. Attachment of the head of the arm to subfiber B is directly demonstrable in splayed axonemes in AMP-PCP. About half of the doublets in an axoneme show such attachments, while half do not. This might imply that about half the doublets in an axoneme are active at any given instant and can be identified as such. This information may be useful in probing questions of how active arms differ biochemically from inactive arms and of how microtubule translocators in general become active.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970100131
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  • 9
    Electronic Resource
    Electronic Resource
    Stepwise sliding disintegration of tetrahymena ciliary axonemes at higher concentrations of ATP (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 9 (1988), S. 191-204 
    Details
    ISSN: 0886-1544
    Keywords: turbidity ; ciliary doublet ; biphasic ; extrusion ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Several characteristics of the sliding disintegration of Tetrahymena ciliary axonemes were found by turbidimetric assay, the ATP-regenerating system, and quantitative determination of the ATP concentration. At ATP concentrations exceeding 40 μM, the response in terms of turbidity was biphasic and could be divided into three phases. The dependence of each phase on ATP concentration was examined. The time duration of phase 2 increased with ATP concentration. When the ATP concentration was kept constant by the ATP-regenerating system, consisting of pyruvate kinase and phosphoenol pyruvate, the time duration of phase 2 increased with the concentration of phosphoenol pyruvate. On examining the change in turbidity with decreasing ATP concentration, the transition from phase 2 to phase 3 was found to occur at an ATP concentration of 40 μM.Dark-field and electron microscopy indicated the sliding disintegration to be closely correlated with the degree of tubidity. At phase 1, one or two doublets extruded from most of the axonemes, and disintegration failed to progress during phase 2. At the transition point from phase 2 to 3, at about 40 μM, ATP, other doublets were noted to extrude from the axonemes one after the other, causing turbidity to be minimal by the end of phase 3.The ATP concentration dependence of stepwise sliding disintegration suggests that each axoneme may possess the ability to regulate doublet microtubule sliding at lower or higher concentrations of ATP. In response to local differences or gradients of ATP concentration along the axoneme, the axonemes may cause localized sliding of doublets, thus subsequently generating active bending movement.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970090302
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  • 10
    Electronic Resource
    Electronic Resource
    Colocalization of F-actin and 34-kilodalton actin bundling protein in dictyostelium amoebae and cultured fibroblasts (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 9 (1988), S. 205-218 
    Details
    ISSN: 0886-1544
    Keywords: F-actin ; actin bundling protein ; cytoimmunofluorescence ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The Ca+2-sensitive actin-binding protein isolated from Dictyostelium discoideum, 30,000-D protein (Fechheimer and Taylor: J. Biol. Chem. 259:4514-4520, 1984;) has recently been localized in filipodia of substrate-adhered amoebae (Fechheimer: J. Cell Biol. 104:1539-1551, 1987). We have determined that this protein has a Mr of 34,000 daltons and is strictly colocalized with actin filaments in both substrate-attached Dictyostelium amoebae and cultured fibroblasts. 3T3 fibroblasts, as well as normal and virally transformed rat kidney fibroblasts (NRK) contain a 34-kilodalton (kD) protein that cross-reacts specifically with antibody to the Dictyostelium bundling protein. Mammalian 34-kD protein is colocalized with F-actin in stress fibers and the cortical cytoskeleton in substratadhered fibroblasts. In substrate-adhered vegetative Dictyostelium, F-actin and 34-kD protein are concentrated in regions of the cell cortex exhibiting filipodia and membrane ridges. Multiple filipodia formed after exposure to the chemoattractant folic acid stain intensely for 34-kD protein, implying participation in the assembly of actin bundles during filipod formation. The cortex of pseudopodia also contained high concentrations of bundling protein, but pseudopod interiors did not. In contrast to vegetative Dictyostelium, F-actin and 34-kD protein were not colocalized in cells that had progressed through the development cycle. In fruiting bodies, 34-kD protein was detected by immunofluorescence microscopy only in prespore cells, while F-actin appeared in stalk cells and spores.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970090303
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  • 11
    Electronic Resource
    Electronic Resource
    Axonal neurofilaments differ in composition and morphology from those in the soma of the squid stellate ganglion (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 9 (1988), S. 349-360 
    Details
    ISSN: 0886-1544
    Keywords: neurofilaments ; intermediate filaments ; neuronal cytoskeleton ; neurofilament heterogeneity ; neurofilament composition ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Triton X-100 insoluble neurofilament (NF) fractions were obtained from two parts of the stellate ganglion and the main giant axon. These were analyzed by one- and two-dimensional gradient polyacrylamide gel electrophoresis, cyclic assembly and disassembly, and electron microscopy. The NF fractions from the ganglion cell bodies (GCB) and from the part of the ganglion mainly consisting of axon initial segments (GIS) were of similar composition; neither contained detectable amounts of the 220 kda and high molecular weight ( 400 kda) NF subunits that were prominent in the axonal NF fraction. However, the GCB and GIS did contain large quantities of a set of 65 kda polypeptides that were minor constituents of the axonal NF fraction. The 65 kda-containing NF fraction from the ganglion could be cyclically disassembled and reassembled, but only under low salt conditions, in contrast to the high salt conditions used to cycle axonal NFs. A comparison of the peptide map of the 65 kda polypeptides with that of the 60 kda axonal NF subunit showed them to be different. These biochemical differences between the ganglionic and axonal NF fractions correlated with morphologic distinctions: ganglionic NFs were relatively smooth surfaced, whereas axonal NFs had long sidearms. Such observations support the hypothesis that the NF cytoskeleton of the neuron soma is different from that of the axon. Furthermore, the change from the somal form to the axonal form of NFs appears to occur in the region where the axon initial segment increases in diameter to become the axon proper.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970090407
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  • 12
    Electronic Resource
    Electronic Resource
    Modulation of nuclear rotation in neuronal interphase nuclei by nerve growth factor, by γ-aminobutyric acid, and by changes in intracellular calcium (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 10 (1988), S. 363-373 
    Details
    ISSN: 0886-1544
    Keywords: nuclear rotation ; karyoplasmic streaming ; nucleus ; nucleolus ; 3-D motion ; time-lapse photography ; NGF ; GABA ; calcium ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Nuclear rotation (NR) is typically measured as motion of nucleoli within nuclei of cells in vitro. This occurs in cycling cells. However, its observation in neurons arrested in interphase indicates that mechanisms related to mitosis are not a prerequisite. We have recently shown that NR occurs in three dimensions within the nuclear space, that it occurs within the space delineated by the outer nuclear membrane and that it includes chromatin domains in addition to nucleoli and have postulated that this motion of chromatin domains is related to changes in gene expression. We now show that exposure of dorsal root, sensory neurons in vitro to nerve growth factor (NGF) or to γ-aminobutyric acid (GABA), agents which alter gene expression, and to agents causing redistribution of calcium, such as EGTA and the calcium ionophore A23187, significantly alters NR. The NGF increased the mean rate of NR and did so at a time after exposure when activity of RNA polymerases have been shown to rise. Exposure to GABA resulted, within minutes, in shifts of the nucleolus within the three-dimensional space of the nucleus, associated in some neurons with significant, sigmoidal increases in the rate of NR. The calcium ionophore A23187 as well as chelation of extracellular calcium with EGTA similarly increased rates. Importantly, excess calcium, with EGTA remaining present, returned NR of all nucleoli to rates not different from controls. This indicates that the increase in NR seen with EGTA is specific to the chelation of calcium and not a nonspecific response to EGTA. It is difficult to link the action of agents which alter gene expression or transmembrane ion balance with changes in NR. Nevertheless, in support of our hypothesis, the results presented here show that agents known to alter gene expression, alter NR in a temporally coincident manner and that they do so, possibly, by calcium-dependent mechanisms.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970100303
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  • 13
    Electronic Resource
    Electronic Resource
    Calcium regulation of flagellar curvature and swimming pattern in triton X-100-extracted rat sperm (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 10 (1988), S. 420-431 
    Details
    ISSN: 0886-1544
    Keywords: sperm motility ; hyperactivation ; vanadate ; nickel ; cadmium ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Free Ca2+ changes the curvature of epididymal rat sperm flagella in demembranated sperm models. The radius of curvature of the flagellar midpiece region was measured and found to be a continuous function of the free Ca2+ concentration. Below 10-7 M free Ca2+, the sperm flagella assumed a pronounced curvature in the same direction as the sperm head. The curvature reversed direction at 2.5 × 10-6 M Ca2+ to assume a tight, hook-like bend at concentrations of 10-5 to 10-4 M free Ca2+. Sodium vanadate at 2 × 10-6 M blocked flagellar motility, but did not inhibit the Ca2+-mediated change in curvature. Nickel ion at 0.2 mM and cadmium ion at 1 μM interfered with the transition and induced the low Ca2+ configuration of the flagellum. The forces that maintain the Ca2+-dependent curvature are locally produced, as dissection of the flagella into segments did not significantly alter the curvature of the excised portions. Irrespective of the induced pattern of curvature, the sperm exhibited coordinated, repetitive flagellar beating in the presence of ATP and cAMP. At 0.3 mM ATP the flagellar waves propagated along the principal piece while the level of free Ca2+ controlled the overall curvature. When Ca2+-treated sperm models with hooked midpieces were subjected to higher concentrations of ATP (1-5 mM), some cells exhibited a pattern of movement similar to hyperactivated motility in capacitated live sperm. This type of motility involved repetitive reversals of the Ca2+-induced bend in the midpiece, as well as waves propagated along the principal piece. The free Ca2+ available to the flagellum therefore appeared to modify both the pattern of motility and the flagellar curvature.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970100309
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  • 14
    Electronic Resource
    Electronic Resource
    Proteolytic fragmentation of Dictyostelium myosin and localization of the in vivo heavy chain phosphorylation site (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 10 (1988), S. 471-481 
    Details
    ISSN: 0886-1544
    Keywords: Dictyostelium ; limited proteolysis ; thick filaments ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Dictyostelium myosin was associated into dimers and small oligomers at very low ionic strength, filamentous at intermediate ionic strength, and monomeric in solution conditions of high ionic strength. These different associations were probed by fragmenting myosin with chymotrypsin, trypsin, or V-8 protease. All three proteases digested monomeric myosin giving rise to multiple fragments with a wide range of molecular weights. Filamentous myosin was not digested by the V-8 protease, was preferentially cleaved at a single site in the middle of the heavy chain by chymotrypsin, and was cleaved at several sites by trypsin. If the reaction was carried out in very low ionic strength, however, two of these proteases generated stable fragments of high molecular weight. Electron microscopic analysis of these stable fragments showed that tails were shorter than in intact myosin, indicating that the cleavage sites were in the rod portion of the molecule. Under the same conditions of enzymatic digestion, myosin that had been radio labeled in vivo with 32P was analyzed by SDS-PAGE and autoradiography. By comparing the state of phosphorylation and the size of the stable fragments, it was determined that the heavy chain phosphorylation site was located between 55 and 70 kD from the tip of the myosin tail, near a region where the tail displayed sharp bends.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970100404
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  • 15
    Electronic Resource
    Electronic Resource
    EGTA induces prolonged summed depolarizations in Mytilus gill coupled ciliated epithelial cells: Implications for the control of ciliary motility (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 10 (1988), S. 464-470 
    Details
    ISSN: 0886-1544
    Keywords: ciliary beat ; cell coupling ; calcium dependency ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Abfrontal ciliated cells of Mytilus edulis gill beat when mechanically stimulated, a consequence of a Ca++-based generator potential and regenerative response. In contrast, the lateral ciliated epithelial cells arrest when stimulated, a consequence of a Ca++-based generator potential and a Na+/Ca++-based regenerative response. Iontophoretic injection of EGTA in abfrontal cells, followed by mechanical stimulation, results in a large, prolonged depolarization that returns to the resting level stepwise. It has been hypothesized that this phenomenon is caused by successive Ca++-dependent repolarizations in coupled cells, first in adjacent cells and then in the injected cell, in accord with relative EGTA loading. We have now demonstrated this same stepwise repolarization phenomenon in the Na+/Ca++-dependent lateral ciliated cells. In this case, each repolarization step is often preceded by a small spike. With either cell type, using two-electrode recording techniques, we can detect the stepwise repolarization in distant cells, proportionately decremented when the second (KCl) electrode is some distance from the injection (EGTA) electrode and stimulus. When force is applied between the electrodes and nearest the KCl electrode, a greater initial response is recorded from this electrode, presumably resulting from depolarization of its impaled cell, prolonged by EGTA diffusion through the intervening cell junctions. The subsequent repolarization steps are of approximately the same size, suggesting repolarization of cells between the two electrodes. These observations are consistent with the cell coupling/EGTA loading hypothesis and indicate that both cell types mediate repolarization through Ca++ and propagate ciliary beat or arrest through intracellular coupling.
    Additional Material: 7 Ill.
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  • 16
    Electronic Resource
    Electronic Resource
    Centripetal transport of cytoplasm, actin, and the cell surface in lamellipodia of fibroblasts (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 11 (1988), S. 235-247 
    Details
    ISSN: 0886-1544
    Keywords: video-enhanced contrast microscopy ; transverse fibers ; transport ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Wound healing in Swiss 3T3 cultures was investigated with video-enhanced contrast (VEC) microscopy. The formation of protrusions at the leading edge of cells along wounds was investigated in detail during the spreading stage, which usually lasted from 1 to 4 hr postwounding. Lamellipodia exhibited a continuous rearward, or centripetal, transport of a variety of cellular constituents at rates of ∼0.26 μm/sec from the leading edge. The lamellipodia were also the sites of lateral migration as well as extension and retraction of actin microspikes. Actin fibers oriented transversely to the direction of movement were also observed to transport centripetally at similar rates. These fibers may in part give rise to large actin fibers forming at the interface between the base of the lamellipodia and the lamellae. Beads 0.5 μm in diameter attached to the dorsal surfaces of lamellipodia also transported centripetally at rates of ∼0.21 μm/sec. Thus there is an apparent correlation between transport of a variety of structures within lamellipodia and with surface movements of lamellipodia.
    Additional Material: 9 Ill.
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  • 17
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    Electronic Resource
    Video supplement assembly, disassembly, and movements of the microfilament-rich ridge during the amoeboflagellate transformation in Physarum polycephalumData corresponding to this article are planned for inclusion in a forthcoming Cell Motility and the Cytoskeleton Video Supplement (1989). (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 11 (1988), S. 223-234 
    Details
    ISSN: 0886-1544
    Keywords: actin ; rhodamine-phalloidin ; cell shape and movement ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The amoeboflagellate transformation in Physarum polycephalum involves a series of dramatic changes in cell shape and motile behavior. This report describes the morphological and behavioral changes through which a synchronously transforming population of cells passes, stressing that, although there are a series of distinguishable stages, cells at all stages display striking plasticity. Our previous studies showed that amoeboflagellates transiently display a flattened motile extension - the ridge - that projects from a specific location on the cell surface and contains a laminar core densely packed with a series of crisscrossing arrays of actin microfilaments. Details are presented here concerning the movements of the ridge as well as the dynamics of ridge formation and disassembly in relation to other morphogenetic events of the transformation. The ridge forms at about the same time as transforming cells begin to elongate, propagates undulations parallel to the long axis of the cell as the transformation proceeds, and disassembles late in the transformation. Staining of fixed cells with the fluorescent probe rhodaminephalloidin shows that the actin of amoeboid cells is strikingly redistributed as the transformation proceeds. Amoeboflagellates contain most of the stainable actin in the ridge and in a ventral-posterior spot that may be a site of cell-substratum adhesion. These results provide additional insights into the possible functions of the ridge and the roles of actin during the amoeboflagellate transformation.
    Additional Material: 9 Ill.
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    URL: http://dx.doi.org/10.1002/cm.970110402
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  • 18
    Electronic Resource
    Electronic Resource
    Correlation between the distribution of smooth muscle or non muscle myosins and α-smooth muscle actin in normal and pathological soft tissues (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 11 (1988), S. 260-274 
    Details
    ISSN: 0886-1544
    Keywords: cytoskeleton ; atheromatosis ; wound healing ; fibromatosis ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The distribution of smooth muscle (SM) and non muscle myosins was compared with that of α-SM actin in various normal and pathological tissues and in cultured cells by means of indirect immunofluorescence using a monoclonal antibody specific for α-SM actin [anti-αsm-1, Skalli et al., 1986b] and two polyclonal antibodies raised against bovine aortic myosin (ABAM) and human platelet myosin (AHPM), respectively.In normal tissues ABAM stained vascular and parenchymal smooth muscle cells (SMC), myoepithelial cells and myoid cells of the testis in a pattern similar to that reported by other authors with antisera raised against non vascular SM myosin. Cells stained with ABAM were always positive for anti-αsm-1. In human and experimental atheromatous plaques, most cells were positive for AHPM; a variable proportion was also stained for ABAM plus anti-αsm-1. Myofibroblasts from rat granulation tissue, Dupuytren's nodule and stroma from breast carcinoma were constantly positive for AHPM and negative for ABAM; however, myofibroblasts from Dupuytren's nodule and breast carcinoma were anti-αsm-1 positive. Early primary cultures of rat aortic SMC were positive for ABAM and anti-αsm-1 and became negative for ABAM and positive for AHPM after a few days in culture. They remained positive for AHPM and anti-αsm-1 after passages; the staining of AHPM and anti-αsm-1 appeared to be colocalized along the same stress fibers.These results may be relevant for the understanding of SMC function and adaptation, and show that in non malignant SMC proliferation, α-SM actin represents a more general marker of SM origin than SM myosin.
    Additional Material: 12 Ill.
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    URL: http://dx.doi.org/10.1002/cm.970110405
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  • 19
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    Microtubules are required for centrosome expansion and positioning while microfilaments are required for centrosome separation in sea urchin eggs during fertilization and mitosis (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 11 (1988), S. 248-259 
    Details
    ISSN: 0886-1544
    Keywords: griseofulvin ; microtubule organizing center ; cell division ; β-mercaptoethanol ; pronuclei ; cytochalasin ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Centrosomes undergo cell cycle-dependent changes in shape and separations, changes that govern the organization of the cytoskeleton. The cytoskeleton is largely organized by the centrosome; however, this investigation explores the importance of cytoskeletal elements in directing centrosome shape. Since the sea urchin egg during fertilization and mitosis displays dramatic and synchronous changes in centrosome shape, the effects of cytoskeletal inhibitors on centrosome compaction, expansion, and separation were explored by the use of anticentrosome immunofluorescence microscopy. Centrosome expansion and separation was studied during two phases: the transition after sperm incorporation, when the compact sperm centrosome enlarges and the sperm aster develops, and from prometaphase to telophase, when the compact spindle poles enlarge. Compaction was investigated when the dispersed centrosome at interphase condenses into the two spindle poles at prometaphase. Although centrosome expansion and separation typically occur concurrently, β-mercaptoethanol results in centrosome separation independent of expansion. Microtubule inhibitors prevent centrosome expansion and separation, and expanded centrosomes collapse. Since pronuclear union is arrested by microtubule inhibitors, this treatment also affords the opportunity to explore the relative attractiveness of the male and female pronuclei for these centrosomal antigens. Both pronuclei acquire centrosomal material; though only the male centrosome is capable of organizing a functional bipolar mitotic apparatus at first division, the female centrosome nucleates a monaster. Microfilament inhibition (cytochalasin D) prevents centrosome separation but not expansion or compaction. These results demonstrate that as the centrosome shapes the cytoskeleton, the cytoskeleton alters centrosome shape.
    Additional Material: 6 Ill.
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    URL: http://dx.doi.org/10.1002/cm.970110404
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  • 20
    Electronic Resource
    Electronic Resource
    The ciliary cycle during hyperpolarization-induced activity: An analysis of axonemal functional parameters (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 11 (1988), S. 275-290 
    Details
    ISSN: 0886-1544
    Keywords: ciliary motility ; inclination ; polarity of beating ; sliding velocity ; sliding translocation rate ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Motor responses of the frontal cirri of the ciliate Stylonychia were recorded at the axial view of the ciliary base with high-speed cinematography. Voltage-clamp applying sustained hyperpolarizing voltage steps was used to explore the properties of the ciliary cycle modulated by the membrane potential. Upon hyperpolarization between - 1 and - 13 mV, a previously inactive frontal cirrus reoriented from a neutral posture and started beating so that the axis of the beating cone of a proximal cirral segment assumed an orientation near 100° (proceeding counterclockwise from posterior = 0°) and inclination near 60° (0° = perpendicular to the cell surface). The major beating amplitude was limited to about 150°. Increasing hyperpolarization increased the spatial polarity of the cycle (ratio of major over minor amplitude, from 2 to 2.4). Rates of the power stroke increased with hyperpolarizations up to - 4 mV but were consistently smaller than those of the return stroke during the ciliary cycle (ratio: 0.4 to 0.6; = temporal polarity). Comparison of different hypothetical beat forms (0-shape, D-shape, and egg-shape) showed that the orientation-time data are the major determinants of the angular velocity and rate of reorientation of the cilium during the cycle. Geometric transformation of these data led to descriptions of the cycle of a proximal ciliary segment in terms of active sliding velocities and rates of unidirectional sliding translocation between identified doublets. Three voltage-sensitive functional parameters of the cilium - the inclination (which is noncyclic) and the rates of active sliding and sliding translocation (both of which are cyclic in nature) - are discussed as generating the spatial and temporal properties of the ciliary beat.
    Additional Material: 13 Ill.
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    URL: http://dx.doi.org/10.1002/cm.970110406
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  • 21
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    Electronic Resource
    Effect of metabolic inhibitors on sucrose-induced metaphase spindle elongation and spindle recovery (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 11 (1988), S. 291-302 
    Details
    ISSN: 0886-1544
    Keywords: mitosis ; mitotic apparatus ; microtubules ; kinetochores ; metabolic inhibitors ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Hyperosmotic sucrose treatment of metaphase PtK-1 cells has been shown to produce a reversible concentration-dependent effect on spindle elongation linked to a functional alteration in the connection of the chromosome to the spindle (Pover et al.: European Journal of Cell Biology 39:366-372, 1985). Spindle elongation, similar to that which occurs at anaphase B, is thought to be driven by the compression stored in the form of microtubule curvature in the nonkinetochore (nkMT) population of microtubules at metaphase (Snyder et al.: European Journal of Cell Biology 35:62-69, 1984 and 39:373-379, 1985). Addition of metabolic inhibitors to Ham's F-12 salts with deoxyglucose (D/F-12 medium) containing 0.4 M sucrose and 1 mM DNP does not within statistical error affect the rate and extent of sucrose-induced spindle elongation; rates and extents are 60-75% of normal anaphase B motions. Electron microscopic analysis of metaphase cells treated with D/F-12 medium and 0.4 M sucrose with 1 mM DNP demonstrates that spindle microtubules lose curvature and become straight in appearance, typical of microtubule organization in untreated anaphase cells. Sucrose-treated cells released into D/F-12 medium show a rapid reduction in spindle length; however, cells treated with either 0.4 M sucrose or 0.4 M sucrose and 1 mM DNP-containing D/F-12 medium and released into DNP-containing D/F-12 medium do not exhibit a significant reduction in spindle length. Electron microscopic analysis links changes in spindle length with microtubule/kinetochore associations. These data suggest that energy required for the initial phases of spindle elongation during anaphase is preloaded into the mitotic spindle by metaphase and does not require additional energy to be expressed as examined by sucrose-induced spindle elongation in the presence of metabolic inhibitors. Second, energy is required to make or maintain (or both) functional chromosome associations with the spindle as measured by reduction in spindle length following sucrose removal.
    Additional Material: 14 Ill.
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    URL: http://dx.doi.org/10.1002/cm.970110407
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  • 22
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    Telechelic sulfate ionomers. I. Preparation and solution and thermal properties (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 367-380 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New telechelic ionomers with zinc and sodium sulfate salt terminal groups on hydrogenated polybutadiene (HPB) backbones (I) were prepared from hydroxyl-terminated hydrogenated polybutadiene (HTHPB) of three different molecular weights (1350, 2100, and 3200 g/mol). Quantitative acid-base titration, elemental analysis, and NMR spectroscopy were used to verify the structure, and further characterization included differential scanning calorimetry (DSC) and solution viscometry. The DSC results indicated that the ionomers are free of impurities within the limit of the resolution of the method. Glass transition temperatures determined by DSC indicated that the elevation in glass transition temperature by ionic crosslinking was most strongly dependent on the molecular weight of the backbone of the telechelic ionomer. The solution viscometry results showed that the sulfation reaction did not cause either covalent crosslinking or chain scission. Furthermore, the solubility characteristics of the sulfate-terminated hydrogenated polybutadiene (STHPB) oligomers were shifted towards a preference for polar solvents by the presence of salt groups. The lower molecular weight ionomers of the series showed polyelectrolyte-like extension at very dilute concentrations in polar solvents. The onset of polymer gelation in hexane was observed for the ionomers which had the highest molecular weight backbones.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260203
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  • 23
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    Polystyrene and polystyrene-butadiene latexes stabilized by poly(N-isopropylacrylamide) (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 9-18 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Latexes stabilized by poly(N-isopropylacrylamide) (polyNIPAM) were prepared by polymerizing NIPAM in the presence of polystyrene and polystyrene-butadiene latex or by styrene emulsion polymerization in the presence of NIPAM. In 0.01 M CaCl2 polyNIPAM stabilized latexes exhibited critical flocculation temperatures in the range 32-35°C, which is approximately equal to the lower critical solution temperature of polyNIPAM in water. Partial substitution of NIPAM with some acrylamide (AM) gave higher flocculation temperatures. Coagulation studies with cleaned latex indicated that the polyNIPAM or polyNIPAM-co-AM polymer chains were anchored to the latex particle surfaces.
    Additional Material: 5 Ill.
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    URL: http://dx.doi.org/10.1002/pola.1988.080260102
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  • 24
    Electronic Resource
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    Ethylene-chlorotrifluoroethylene copolymers. II. Effects of structure on resistance to thermal stress cracking (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 43-59 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Copolymers of ethylene and chlorotrifluoroethylene that contain small amounts of units derived from perfluorohexylethylene show improved resistance of thermal stress cracking. This is a consequence of effects of these units on structural parameters of both the crystalline and amorphous phases. Those of the crystalline phase entail growth and organization of lamellae, whereas those of the amorphous phase are related to conformation and packing of polymer chains. The crystalline phase consists exclusively of alternately arranged units of ethylene and chlorotrifluoroethylene. The amorphous phase is characterized by chain segments composed of randomly distributed units derived from ethylene, chlorotrifluoroethylene, pairs of these two units, and units derived from perfluorohexylethylene.
    Additional Material: 17 Ill.
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    URL: http://dx.doi.org/10.1002/pola.1988.080260105
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  • 25
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    Comparison of methods of calculation of 13C-NMR chemical shifts of diene polymers with applications to isomerized natural rubber (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 615-626 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Natural rubber was isomerized by two methods that involved either dehydrobromination of hydrobrominated natural rubber or heating natural rubber with butadiene sulfone. The 13C-NMR spectra of the methylene region of isomerized natural rubber was interpreted in terms of dyad arrangements for which assignments were made by calculating chemical shifts according to three different published methods. One method [Gronski, Murayama, Cantow, and Miyamoto, Polymer, 17, 358 (1976)] gave the best overall agreement with the experimental chemical shifts; another [Sato, Ono, and Tanaka, Polymer, 18, 580 (1977)] was better for C-1 and C-3 methylene carbon atoms; and still another [Khatchaturov, Dolinsky, Prozenko, Abramenko, and Kormer, Polymer 18, 871 (1977)] gave results which deviated considerably from the other methods. From 13C-NMR intensity measurements it was shown that the elimination of HBr from hydrobrominated natural rubber occurred by a random process. Contrary to literature reports, it was found that the sulphur dioxide catalyzed isomerization of natural rubber was accompanied by a significant amount of double bond migration; a possible reaction scheme was proposed.
    Additional Material: 2 Ill.
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    URL: http://dx.doi.org/10.1002/pola.1988.080260225
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  • 26
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    Polymerization of oxiranes by polymeric organoantimony oxides (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 627-636 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymeric arylantimony(V) oxides [poly(ArSbO2), Ar = phenyl, p-chlorophenyl (CPh), and p-methylphenyl (Tol)] were employed as catalysts for the polymerization of oxirane [ethylene oxide (EO)] and also substituted oxiranes [propylene oxide (PO), 1,2-butylene oxide (BO), and epichlorohydrin (ECH)]. The polymerization of EO by ArSbO2s proceeded 3-60 times faster than that by the other organoantimony and -tin compounds such as triphenylstibine oxide (Ph3SbO) and arenestannoic acids (ArSnO2H), respectively. Apparent activation energy for the polymerization of EO was estimated as 13.7, 13.3, and 13.6 kcal/mol for PhSbO2, TolSbO2, and CPhSbO2, respectively. The results of the polymerization as well as 1H-, 13C-, and 17O-NMR spectroscopy suggested that the polymerization was initiated by ArSbO2 or Ar2Sb2O4 fragments, which was derived from a nucleophilc solvation of the polymeric ArSbO2 by oxiranes in situ.
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    URL: http://dx.doi.org/10.1002/pola.1988.080260226
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  • 27
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    Organic solid photochromism by photoreduction mechanism: Aryl viologens embedded in poly(N-vinyl-2-pyrrolidone) (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 653-656 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/pola.1988.080260228
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  • 28
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    Furanized rubber studied by NMR spectroscopy (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 637-651 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The double bonds of natural rubber latex (stabilized by a nonionic surfactant) were reacted with an approximately equimolar amount of performic acid at room temperature with a limited amount of formic acid present. Product analysis by 1H-NMR during the course of the reaction showed that 69-90% epoxidation occurred before the advent of ring opening and ring expansion to produce furanized rubber; hence the rate of epoxidation was greater than the rate of furanization. Indeed, at lower concentrations of formic acid and rubber latex, epoxidation occurred to 90% and furanization was prevented; it was subsequently brought about by the addition of a catalytic amount of orthophosphoric acid. Increased formic acid concentration caused early coagulation of the modified rubber latex. By 1H- and 13C-NMR, it was found that the furanized rubber probably consisted of tetrahydrofuran rings linked together by C—C bonds at positions adjacent to the hetero atom and contained a terminal hydroxy group. The number average sequence length was 2-9, but only the sample with an average sequence length of 9 was effective as a cation binder.
    Additional Material: 6 Ill.
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    URL: http://dx.doi.org/10.1002/pola.1988.080260227
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  • 29
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    Functional polymers. XLVII. Synthesis of various derivatives of ω-alkenoatesPart XLVI: P. M. Gomez, L. P. Hu, and O. Vogl, Polym. Bull., 15(2), 135 (1986). (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 657-675 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A number of derivatives of ω-alkenoates were synthesized in preparation for the synthesis of functional polymers based on α-olefins. For the preparation of most of the methyl esters, the regular esterification of ω-alkenoic acids, specifically 10-undecenoic acid with methanol and sulfuric acid as the catalyst, was most effective. For the preparation of the tert-butyl- and 2-ethylhexyl esters of 10-undecenoic acid, the acid chloride route was found to be most convenient, whereas for the preparation of the corresponding esters of 5-hexenoic acid, our method of choice was the synthesis via the imidazolyl derivative of the acid. 2,2,2-Trifluoroethyl 10-undecenoate and the 2,2-dimethyloxazolidine derivative of 10-undecenoic acid were prepared from the acid and 2,2,2-trifluoroethanol or 2-amino-2-methyl-propanol with p-toluene sulfonic acid as the catalyst. Esters of phenol, 2,6-dimethylphenol, and 2,6-diphenylphenol were synthesized from 3-butenoic and 10-undecenoic acid with trifluoroacetic anhydride.
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    URL: http://dx.doi.org/10.1002/pola.1988.080260301
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    Synthesis and properties of polyamides derived from systematically halogenated terephthalic acids with fluorine, chlorine, or bromine atoms (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 235-245 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Aromatic polyamides were prepared from systematically halogenated terephthalic acids with hexamethylene diamine, piperazine, 4,4′-diaminodiphenylether and p-phenylene diamine by interfacial or low temperature solution polycondensation. The halogenated terephthalic acids used have mono-, di-, or tetra-substituted fluorine, chlorine, or bromine atoms on the benzene ring. The nonhalogenated terephthalic acid was also used for the comparison. The effects of halogen substitution on the benzene ring on the synthesis and some properties of polymers were examined. Reduced specific viscosity decreased in the order F 〉 Cl 〉 Br by halogen substitution. The incorporation of halogen substituents on the ring led to a decrease of crystallinity and fluoro-substituents hindered the crystallization more strongly. The melting point (Tm) decreased in the order F 〉 Cl 〉 Br by mono-substitution, and Br 〉 Cl 〉 F by di-and tetra-substitution. The change of Tm caused by the difference of the number of halogen substituents differed depending on the rigidity of polymer chains. The flame-retardancy estimated by thermogravimetry, self-ignition, and flash-ignition test increased with increasing halogen content of the polymers. Solubility increased remarkably by halogen substitution. The peak temperature of tan δ decreased by halogen substitution. Some discussion was made on these effects of halogen substitution.
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    URL: http://dx.doi.org/10.1002/pola.1988.080260123
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  • 31
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    Electro-initiated polymerization of acrylonitrile in aqueous acetic acid containing Mn(OAc)2·4H2O and CNCH2COOH (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 301-311 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The electro-initiated polymerization of acrylonitrile initiated by the anodic oxidation of an aqueous acid solution (80% HOAc + 20% H2O) containing Mn(OAc)2 · 4H2O/CNCH2COOH has been investigated in the 30-40°C temperature range. The kinetics and mechanism of the process has been investigated as a function of variables and a suitable mechanism proposed. From the experimental observations the rate of polymerization is seen to be proportional to [An]1.5I0.5[Mn+2]0.5 and [CAA]0.5. The rate of polymerization gradually decreases at a higher applied current. The rate was independent of [CAA]0.5. The rate of polymerization gradually decreases at a higher applied current. The rate was independent of CAA at high concentration. The average degrees of polymerization (Pn) increases with increasing AN and decreasing [CAA], [Mn+2] and applied current, I. The initiation is due to the anodic oxidation of Mn+2-CNCH2COOH complex. Both the initiation of polymerization by the primary radical, viz., CN—CḢ—COOH as well as the oxidation of the primary radical at the electrode are equally significant reactions and neither can be neglected in comparison with the other. Predominant mutual termination accounts for all the observed data.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260129
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    Electronic Resource
    Electronic Resource
    Separation of water from aqueous ethanol solution through quaternized poly(4-vinylpyridine-co-acrylonitrile) membranes (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 335-340 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260133
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  • 33
    Electronic Resource
    Electronic Resource
    Comparative study of the absolute reactivity of vinyl monomers: Kinetics of polymerization of vinyl monomers initiated by Mn3+-thiodiglycolic acid redox system (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 355-366 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics and mechanism of polymerization of methacrylic acid (MAA) and ethyl acrylate (EA) initiated by the redox system, Mn3+-thiodiglycolic acid (TDGA) were investigated in the 15-35°C temperature range. The polymerization kinetics of both the monomers followed the same mechanism, viz., initiation by primary radical and termination by Mn3+-thiodiglycolic acid complex. The rate coefficients ki/k0 and kp/kt were related to the monomer reactivity and polymer radical reactivity, respectively. It was observed that both monomer reactivity and polymer radical reactivity followed the same order, viz., EA 〉 MAA. The polymer radical reactivity varied inversely with the Q values of the monomers.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260202
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  • 34
    Electronic Resource
    Electronic Resource
    Chemistry of epoxide-polycarbonate copolymer networks (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 247-254 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Diepoxides and in-chain carbonate groups react readily in the presence of quarternary ammonium salts, although reaction is not observed without this catalyst. Two moles of epoxide react with each mole of carbonate. When diepoxides and polycarbonates are reacted, a three-dimensional network of chains crosslinked with carbonate groups is produced; the crosslink density is controlled by adjusting the epoxy/carbonate ratio. Tertiary amines and alkoxides also catalyze the epoxy/carbonate reaction, but these have the undesirable attribute of promoting epoxy polymerization. The presence of oligocarbonates accelerates the epoxy-amine reaction.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260124
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  • 35
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    Electronic Resource
    Preparation and properties of 1-ethoxy-2,2,2-trifluoroethyl esters of acrylic and methacrylic acids and of their polymers (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 267-274 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1-Ethoxy-2,2,2-trifluoroethyl esters of acrylic (I) and methacrylic (II) acids were synthesized from 1-ethoxy-2,2,2-trifluoroethanol and acryloyl- and methacryloylchloride, respectively, and their densities, mass, 1H- and 13C-NMR spectra were measured and the rate constants of hydrolysis were determined. Poly(I) and poly(II) were prepared by radical homopolymerization; the rates of polymerization, specific volume contractions in polymerization, limiting viscosity numbers, average number degrees of polymerization, temperature dependences of the heat capacities both in glass and liquid state, glass transition temperatures, and the initial temperature of the spontaneous thermal decomposition of homopolymers were determined. The monomer reactivity ratios of the styrene (S) copolymerizations, S—I and S—II, and the Alfrey-Price copolymerization constants e and Q for I and II were calculated from the composition of copolymers of I and II with styrene.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/pola.1988.080260126
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  • 36
    Electronic Resource
    Electronic Resource
    Nonclassical urea oligomers. IX. Photo-reducing nature of binuclear copper complexes of noncyclic pendant-type urea oligomersPaper VIII of this series: see Ref. 1. (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 285-299 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The octameric oligomers of 1-(N-substituted-carbamoyl)-aziridine, i.e., N-ureanized-oligo-ethylenimines, form Cu(II) complexes. When the N-substituents are phenyl(1, 3), methyl(2), and p-tolyl(4) groups, the main portions of the Cu(II)-complexes are binuclear. The binuclear oligomer-Cu(II) complexes showed characteristic properties of photo-reduction of Cu(II) species, giving rise to stable yellow Cu(I) species. The ease of photo reduction strongly depends on the oligomer structures, especially on the nature of the pendant-urea groups, i.e., 4 〉 1,3 〉 2. In the series of aromatic type urea-oligomers, highly stable photo-radicals were observed in ESR. By using an optically active oligomer (3) the molecular requirements for these characteristic properties were investigated with circular dichroism and cyclic voltammometry. And one of the plausible structures was deduced as the model of binuclear Cu(II) sites surrounded by oligomeric environments.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260128
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  • 37
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    Studies on diacetylenic vinyl compounds. II. Copolymerization of phenyl-4′-vinylphenylbutadiyne with styrene and methyl methacrylate (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 321-327 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The copolymerizations of phenyl-4′-vinylphenylbutadiyne (PVPB) with styrene and methyl methacrylate were carried out under various conditions. PVPB was more readily incorporated in copolymerization than the comonomers, but the diacetylenic group of PVPB interacted with the propagating radical, decreasing the polymerization rate and the molecular weight of copolymer. When the polymerization system became very viscous, crosslinking took place giving light green luminescent gels. The thermal behaviors of copolymers were also studied.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260131
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  • 38
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    Electronic Resource
    The introduction of hydroxyl functionality into polymers: The synthesis, polymerization, and hydrolysis of vinylbenzyl acetate (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 343-353 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Vinylbenzyl acetate was synthesized in yields greater than 80% via the reaction of vinylbenzyl chloride with potassium acetate. Radical copolymerization of the monomer with styrene and methylmethacrylate were studied at 60°C. Reactivity ratios determined from FT-IR analysis of low conversion copolymerizations with styrene (M1) were r1 = 0.78 ± 0.07 and r2 = 1.33 ± 0.13. Polymers and copolymers of vinylbenzyl acetate were found to completely hydrolyze in dioxane/water/base solution to yield hydroxymethyl functionality. Size exclusion chromatography studies indicated that the hydrolysis proceeded without crosslinking. This procedure is a useful method for the introduction of hydroxyl functionality on polymers and avoids crosslinking problems common in previously reported methods.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260201
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  • 39
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    Electronic Resource
    Synthesis and characterization of polystyrene-poly(ethylene oxide)-heparin block copolymers (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 381-391 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A procedure for the preparation of new block copolymers composed of a hydrophobic block of polystyrene, a hydrophilic spacer-block of poly(ethylene oxide) and a bioactive block of heparin was investigated. Polystyrene with one amino group per chain was synthesized by free radical oligomerization of styrene in dimethylformamide, using 2-aminoethanethiol as a chain transfer agent. This amino group was used in the coupling reaction with amino-telechelic poly(ethylene oxide) to produce an AB type diblock copolymer with one amino group per polystyrene (PSt)-poly(ethylene oxide) (PEO) chain. The amino-semitelechelic oligo-styrene was converted into the isocyanate-semitelechelic oligo-styrene using toluene 2,4-diisocyanate and subsequent coupling with H2N-PEO-NH2 afforded AB type block copolymers with terminal amino groups. The coupling of PSt-PEO-NH2 with heparin was performed in a DMF-H2O mixture, first by activating the heparin carboxylic groups with EDC at pH 5.1-5.2 and subsequently reacting the activated carboxylic groups with the amino groups of the PSt-PEO-NH2 at pH 7.5. Depending on the molecular weights of the diblock copolymer used 25-29% w/w heparin was incorporated. These polymers will be further evaluated for their blood-compatibility.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260204
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    Preparation of polysiloxanes from silicic acid. X. Preparation and properties of allyldimethylsilylated silicic acids (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 419-427 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In order to obtain polysiloxanes capable of forming a film, the preparation and properties of allyldimethylsilylated silicic acid was investigated. The reaction in variable molar ratios of allyldimethylchlorosilane to silicic acid gave partially silylated silicic acids with different degrees of silylation. They provided not only fibrous polysiloxanes but also films from concentrated polymer solutions. Spinnability and film formation depended on the solvent, degree of silylation, molecular weight, and allyl group.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260207
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  • 41
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    Electronic Resource
    Highly active supported catalysts for olefin polymerization. Supports from a grignard reagent for preparation of highly active catalysts (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 457-464 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Supports were obtained by the interaction of C4H9MgCl with the reaction mixture of AlCl3 and CH3Si(OC2H5)3 or Si(OC2H5)4 (Mg/Al/Si = 2/1/1). With the combination of Al(C2H5)3 and methyl-p-toluate, immobilized titanium catalysts prepared by the treatment of the supports with TiCl4 and ethylbenzoate showed extraordinary high activity and stereoregularity in the polymerization of propylene.1 By the study of the reaction of AlCl3 with CH3Si(OC2H5)3, the elemental analysis and powder x-ray diffractometric measurements of the supports, it was found that the supports comprised of Cl, Mg, Al, and Si atoms, OC2H5 groups, C4H9 groups, and ethers, and that they were amorphous solids to the extent that the x-ray diffraction peak assigned to the 003 plane in MgCl2 crystals completely disappeared.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260210
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  • 42
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    Electronic Resource
    Polymerization of methyl methacrylate with ferric laurate in combination with various substituted amines as initiators (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 901-911 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The effect of various substituted amines on the polymerization of methyl methacrylate initiated by ferric laurate - amine as the initiator system has been studied in carbon tetrachloride medium at 60°C. Amines used are n-butyl amine, di-n-butyl amine. The rate of polymerization is found to follow the order: tertiary 〉 secondary 〉 primary amine. From the detailed kinetic studies it was found that the overall polymerization rate can be expressed by the equation: \documentclass{article}\pagestyle{empty}\begin{document}$ R_p = \frac{{k_p }}{{k_t^{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} }}(k_1 f)^{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} [{\rm Monomer}][{\rm Fe}^{3 + } ]^{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} [{\rm Amine}]^{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} $\end{document} The relative activity of the different amines has been found to be dependent on the relative electron-donating tendency of the substituents present in the amine. The mechanism of the polymerization is discussed on the basis of these results, and various kinetic constants are evaluated.
    Additional Material: 8 Ill.
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    URL: http://dx.doi.org/10.1002/pola.1988.080260318
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  • 43
    Electronic Resource
    Electronic Resource
    Amorphous polyaramides with low glass transition temperatures (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 959-962 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260322
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  • 44
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    Electronic Resource
    Monte Carlo estimation of kinetic parameters in polymerization reactions (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 965-971 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A general method for estimating kinetic parameters in polymerization reactions using Monte Carlo simulation to represent the models of the reactions is developed. From a statistical point of view, the procedure is a Bayesian one in which a posterior probability density surface (PPDS) is calculated for points on a grid in the parameter space. A smoothing function is fitted to the PPDS, then a posterior probability region, which is similar to a confidence region, is calculated for the parameters. An application to a relatively trivial example, the Mayo-Lewis copolymerization model is shown in detail. Many other potential applications are suggested.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260401
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  • 45
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    Electronic Resource
    Linear A-B and AA-BB polyamides with backbone aryl, alkyl, and alkenyl units (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2345-2354 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: High performance linear AA-BB and A-B polyamides were generated using polymerization schemes that gave polymers in higher yields and having better performance than previous methods. Polymers were characterized with FTIR, solution and solid-state 13C-NMR and showed the incorporation of aryl, alkyl, and alkenyl linkages in the polymer backbone. Thermal analysis showed that a significant weight percent of the polymers remained at 1000°C.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260907
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  • 46
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    Electronic Resource
    Synthesis of polyphthalocyanines by an oxidoreduction reaction initiated by the benzhydrol functional group. I. Model study (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 865-883 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A novel route for the thermal conversion of bis(phthalonitrile)monomers into metal-free phthalocyanine network polymers was investigated on the basis of a model study on the tetramerization reaction of 4-benzoylphthalonitrile and benzhydrol derivatives into metal-free phthalocyanine compounds. This procedure of conversion of phthalonitrile derivatives involved an oxidoreduction reaction initiated by the alcohol functional group of benzhydrol coreactant. The influence of molar ratio of phthalonitrile and benzhydrol functional groups, chemical environment of the benzhydrol reducing group has been studied by microcalorimetry and electronic spectroscopy. It was observed that the theoretical 4 : 1 phthalonitrile: benzhydrol molar ratio is respected and the reductive capacity of the benzhydrol group is increased by the electron withdrawing effect of its substituants.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260316
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  • 47
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    Electronic Resource
    Flame retardation of polyurethanes by means of 1,4-bis[(dialkoxyphosphinyl)hydroxymethyl]benzene (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 885-900 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New phosphorus-containing homopolyurethanes were synthesized by reacting various diisocyanates such as tolylene diisocyanate, methylenebis(4-phenylisocyanate) and hexamethylene-1,6-diisocyanate with 1,4-bis[(dialkoxyphosphinyl)hydroxymethyl]benzene (BDAB). In addition, copolyurethanes containing approximately 3% phosphorus were prepared by copolymerization of these diisocyanates with an equimolar amount of BDAB - hydroquinone mixture. BDAB was less reactive towards diisocyanates than hydroquinone due to the electron-withdrawing inductive effect of the phosphinyl groups. The polymers synthesized were characterized by inherent viscosity measurements as well as by proton nuclear magnetic resonance (1H-NMR) and infrared (IR) spectroscopy. The spectroscopic examination of polymers did not provide evidence for crosslinking by allophanate groups. Differential thermal analysis (DTA) studies of polymers revealed that the incorporation of BDAB in polyurethanes altered their thermal decomposition mode by increasing the exothermicity due to pyrolysis. Thermogravimetric analysis (TGA) of polymers showed that the phosphorus-containing homopolyurethanes and copolyurethanes were thermally less stable than the corresponding common polyurethanes but afforded higher char yields. Determination of the limiting oxygen index (LOI) values showed that the phosphorus-containing copolyurethanes exhibited a higher fire resistance than that of common polyurethanes.
    Additional Material: 2 Ill.
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    URL: http://dx.doi.org/10.1002/pola.1988.080260317
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    Electronic Resource
    Decomposition rate studies of azobisnitriles containing functional groups (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 953-958 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260321
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  • 49
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    Radical-catalyzed homopolymerization of maleic anhydride in presence of polar organic compounds (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1903-1909 
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    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polar organic compounds either (1) inhibit the peroxide-catalyzed bulk homopolymerizations of both MAH and MMA at 80°C, (2) do not inhibit the polymerization of either MAH or MMA, or (3) inhibit the polymerization of MAH but not that of MMA. Compounds generally used as polymerization inhibitors or antioxidants inhibit the polymerizations of both MAH and MMA, presumably by interaction with peroxide decomposition products. Ketones, ethers, acids, esters, nitriles, imides, sulfones, sulfonates, sulfonamides, and acyl disulfides do not inhibit either MAH or MMA polymerization. However, amides, lactams, carbamates, amine oxides, phosphites, phosphates, phosphonates, phosphoramides, phosphine oxides, monosulfides, sulfoxides, aryl disulfides, and thiazyl disulfides inhibit the polymerization of MAH but not that of MMA. Inhibition presumably occurs as a result of electron transfer from the nitrogen-, phosphorous- or sulfur-containing electron donor compound to the MAH carbocation which is an intermediate in the polymerization of MAH.
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    URL: http://dx.doi.org/10.1002/pola.1988.080260716
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  • 50
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    Mechanistic and kinetic studies on the photoinitiated polymerization of tetrahydrofuran (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1911-1918 
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    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymerization of tetrahydrofuran (THF) (bulk) promoted by a free radical source, 2,2-dimethoxy-2-phenyl acetophenone (DMPA), in the presence of 4,4′-di-(methylphenyl)iodonium hexafluorophosphate was studied in detail. Rate dependence of the polymerizing system on both DMPA and the iodonium salt was studied dilatometrically. Rate saturation for the iodonium salt was attributed to the formation of iodobenzene, which may react with propagating cations to form an iodonium salt. DMPA was shown to be an efficient transfer agent in the cationic polymerization of THF. A transfer constant for DMPA was estimated to be 2.8 and, whilst the precise details of the overall mechanism cannot be deduced from the present results, it may result in functionalized polytetrahydrofuran chains having photochemically active end groups.
    Additional Material: 3 Ill.
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    URL: http://dx.doi.org/10.1002/pola.1988.080260717
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    Characterization of polyethylene terephthalate by gel permeation chromatography (GPC) (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1919-1935 
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    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The use of the solvent mixture chloroform/hexafluoroisopropanol (98 : 2 vol %) in the GPC-analysis of polyethylene terephthalate (PET) is described. PET-samples of different molecular weight have been prepared and characterized by light scattering, viscometry, and improved techniques of osmometry and end group titration. These well characterized samples were used in calibrating the GPC. The calibration with polydisperse standards was found superior to the universal calibration procedure in the solvent system chosen.
    Additional Material: 9 Ill.
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    URL: http://dx.doi.org/10.1002/pola.1988.080260718
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  • 52
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    Emulsifier-free emulsion copolymerization of styrene and butyl acrylate. II. Kinetic studies in the presence of ionogenic comonomers (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1937-1959 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Batch emulsifier-free copolymerizations of styrene (S) and butyl acrylate (BuA) have been performed for a S/BuA weight ratio = 50/50 in the presence of two types of functional comonomers [methacrylic acid (MAA) at different pHs] or potassium sulfopropylmethacrylate (SPM) and two initiators [potassium persulfate or 4-4′azobiscyanopentanoic acid (AZO)]. The use of AZO/MAA system results in the formation of polymer particles with only surface carboxylic end groups. The particle size of the final latexes can be adjusted with the MAA concentration, provided the polymerization is carried out at pH 〉 6.5. However, the higher the MAA concentration, the sooner the polymerization levels off in conversion. With the K2S2O8/SPM system, particles bearing only sulfate and sulfonate groups are produced and the polymerization is complete. In that case, the particle size of the final latexes is smaller than with the previous system and 30% of the SPM is fixed on the particle surface, instead of 10% with MAA. Using SPM, a too high functional monomer concentration results in the latex destabilization caused by the formation of a large amount of polyelectrolytes. Kinetic studies indicate that most of the functional monomer is incorporated onto the particle surface during the last 30% conversion of the polymerization. A tentative explanation of such a behavior is discussed, based on the existence of two polymerization loci in the latex system.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260719
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    A new approach to high temperature photoresists based on styrylpyridinium units (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2517-2527 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Four linear polyesters containing styrylpyridinium units were prepared from 2,6-bis(p-hydroxystyryl)pyridine and terephthalic acid, isophthalic acid, adipic acid, and sebacic acid, respectively. The polyesters are thermally stable in the 365 to 450°C range. The decomposition temperature is higher for aromatic polyesters, lower for their aliphatic analogs. The polyesters are photoreactive and crosslink on irradiation with UV. The crosslinking mechanism is 2 + 2 cycloaddition. The polyesters form protonated complexes with CF3COOH which absorb at longer wavelengths and are also photoreactive. The quantum yield of the photoreaction and the relative photosensitivities of the polyesters and their complexes were determined.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260921
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  • 54
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    Reactive oligomers. V. Polymerization of ethylene glycol bis(isopropyl fumarate), ethylene glycol bis(n-butyl fumarate), and diethylene glycol bis(n-butyl fumarate) (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1975-1977 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260722
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    Syntheses and characterization of poly(benzimidazolyl) thiaxanthones (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1051-1061 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Novel polybenzimidazoles containing thiaxanthone heterocyclic units were synthesised from 2,7-thiaxanthonedicarboxylic acid-5,5′-dioxide and 2,8-thiaxanthonedicarboxylic acid-5,5′-dioxide and two aromatic tetramine hydrochlorides by PPA solution polycondensation in 60-70% yield. Two model compounds, 2,7-bis(2-benzimidazolyl)thiaxanthone-5,5′-dioxide and 2,8-bis(2-benzimidazolyl)thiaxanthone-5,5′-dioxide, were prepared and characterized by spectral methods. The polybenzimidazoles have inherent viscosities in the range 1.13-1.50 dL/g and decomposition temperatures of 495-560°C. The effect of thiaxanthone units on polymer properties are discussed.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260409
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  • 56
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    Synthesis and characterization of polyamides containing heterocyclic thiaxanthone units (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1063-1076 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Novel polyamides containing heterocyclic thiaxanthone units were prepared by condensing 2,7-dichloroformylthiaxanthone-5,5′-dioxide and 2,8-dichloroformylthiaxanthone-5,5′-dioxide with various aromatic diamines, under low temperature solution polymerization conditions in DMAc. The model diamide, 2,8-ditolylcarbamylthiaxanthone-5,5′-dioxide was synthesised and characterized by spectroscopic methods. The polyamides were prepared in 70-80% yield and had inherent viscosity in the 0.36-0.73 dL/g range. The poyamides have decomposition temperatures in the 425-510°C range in nitrogen. The effect of thiaxanthone rings on polymer backbone on solubility, crystallinity, and thermal stability is also discussed.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260410
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    Surface tension of a curing epoxy (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1985-1988 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260724
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    Synthesis, bulk characterization, and surface characterization of p-hydroxystyrene/styrene copolymers (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1991-2002 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Styrene/p-hydroxystyrene copolymers were prepared from copolymers of styrene and p-benzyloxystyrene by cleavage of the ether bond. Nuclear magnetic resonance spectroscopy was used to characterize the polymers before and after the ether cleavage reaction. Reactivity ratios were calculated by applying the method of least squares to data generated from the Fineman-Ross equation (r1 = 0.37, r2 = 0.28). The surface chemistry of centrifugally cast films of the homopolymers and the copolymers was studied by using electron spectroscopy for chemical analysis (ESCA). The Zisman contact angle method was used to determine the critical surface tension in air for each polymeric surface. Water contents of hydrated films were determined gravimetrically. The polar character of the surface was shown to increase to a small degree with an increase in the p-hydroxystyrene component. Polymers with high p-hydroxystyrene contents did not exhibit pronounced hydrogel character.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260801
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    Superactive and stereospecific catalysts. I. Structures and productivity (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2003-2018 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two series of catalysts were made, one from MgCl2-A solution containing MgCl2, EH (2-ethylhexanol), and EB (ethyl benzoate) dissolved in decane and another from MgCl2-B solution containing MgCl2, EH, and phthalic anhydride which reacted to form the corresponding phthalic ester. Reactions of these solutions with TiCl4 with or without another ester produced a family of eight catalysts. They form two groups, one having monoesters as modifiers, and the other containing diesters as modifiers. The surface area, pore volume, x-diffractions, polymerization activity, and catalytic stereospecificity of these catalysts have been compared. The diester catalysts differ from the monoester catalysts in every respect. By comparison the corresponding member of the diester catalysts have half as much Ti per Mg, more than 10 times the pore volume, more than a 100-fold the surface area, about 50% more productivity, and greatly increased steroespecificity.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260802
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  • 60
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    Graft copolymerization of cellulose initiated by ceric salts: Effect of reaction conditions on the consumption of ceric ion (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2019-2029 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A soluble monomer [methyl acrylate (MA)] and an insoluble monomer [butyl methacrylate (BMA)] were grafted onto cellulose by three types of ceric salts under both oxygen-free conditions and in the presence of oxygen. For comparison, Ce(IV) consumption during cellulose oxidation was also determined under similar reaction conditions. Slightly more Ce(IV) was consumed during cellulose oxidation in the presence of oxygen. During graft copolymerization of MA under oxygen-free conditions, the consumption of Ce(IV) was much lower than during cellulose oxidation regardless of the type of ceric salt employed. The opposite was observed in the presence of oxygen: much more Ce(IV) was consumed during grafting than during cellulose oxidation. The consumption of Ce(IV) in the graft copolymerization of BMA by ceric sulfate was nearly independent of reaction conditions and it was approximately the same as in cellulose oxidation. In the reaction initiated by ceric ammonium nitrate under oxygen-free conditions, less Ce(IV) was once again used up during grafting than during cellulose oxidation. However, the difference was much smaller than in the case of MA.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260803
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    Characterization of the functionalization reaction product of poly(styryl)lithium with ethylene oxide (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2031-2037 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The functionalization reaction of poly(styryl)lithiums (Mn = 1.3-9.9 × 103) with ethylene oxide in benzene proceeds quantitatively ( 〉 99%) to produce the corresponding hydroxyethylated polymer as determined by vapor phase osmometry, size exclusion chromatography, end-group titration, thin layer chromatography, and 1H- and 13C-NMR spectroscopy. 13C-NMR spectral analysis of the functionalized polystyrene with Mn = 1.3 × 103 was consistent with addition of only one ethylene oxide unit to poly(styryl)lithium, i.e., no evidence for ethylene oxide oligomerization was observed.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260804
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    Visible light induced polymerization of vinyl monomers sensitized by a thiopyrylium salt with a peroxyester (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1671-1675 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260617
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    High performance size exclusion chromatography of polyamic acidPortions of this article were presented at the November 1985 The Society of Plastic Engineers Second International Conference on Polyimides, Ellenville, NY. (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1649-1657 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Molecular weight studies of polyamic acids are complicated by polyelectrolyte effects. Although early work on the molecular weight determination of polyamic acids employed salts to suppress this polyelectrolyte effect, recent publications reveal that such salts can cause precipitation of polyamic acids from solution, however, a mobile phase consisting of 0.03M LiBr/0.03M H3PO4/1% vol THF in dimethyl formamide was reported to successfully suppress the noted polyelectrolyte effect without causing the precipitation of polyamic acid and give satisfactory size exclusion chromatograms using columns packed with “macro-porous” glasses. However, the development time was long (ca. 4 h) and considering the lability of the polyamic acids, the results must be viewed with skepticism. We find that use of a similar “mixed” mobile phase with Zorbax® PSM-Bimodal columns using size exclusion chromatography in the high performance mode (HPSEC) provides well resolved and reproducible chromatograms and molecular weight data with development times of 〈 15 min. Aside from the avoidance of long development times, which can lead to questionable results, this procedure permits the facile routine analysis of polyamic acid on a daily basis. The procedure has great utility as an analytical tool to support fundamental studies of polyamic acid chemistry and two examples of this application are given.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260615
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    Poly(Schiff base) polymers based on substituted biphenyl (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1677-1680 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260618
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    Nucleic acid base grafted imino polyurethane (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1659-1669 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Preparation of two model polymers of polynucleotides with linear polyurethane backbone and 2-(thymin-1-yl)propionyl or 2-(uracil-1-yl)propionyl group as grafted pendant are described. 2-(Thymin-1-yl)propionic acid (TPA) and 2-(uracil-1-yl)propionic acid (UPA) were grafted into partial imino functionalized polyurethane, poly[(β,β′-diethylene)amine methylene bis(4-phenylcarbamate)]-75 (PU-NH-75), at the secondary amino group through amide bonds with 1-hydroxybenzotriazole (HOBT) using the active ester technique. Two novel polymer models of polynucleotides, poly[(N-(2-(thymin-1-yl)propionyl)-β,β′-diethylene)amine methylene bis(4-phenylcarbamate)]-75 (PU-NT-75) and poly[(N-(2-(uracil-1-yl)propionyl)-β,β′-diethylene)amine methylene bis(4-phenylcarbamate)]-75 (PU-NU-75) were obtained. The imino polyurethane PU-NH-75 was produced from the partially deprotected N-Cbz imino polyurethane, poly[N-(benzyloxycarbonyl-β,β′-diethylene)amine methylene bis(4-phenylcarbamate)] (PU-NCbz) which was prepared by the polyaddition of 4,4′-diphenylmethane diisocyanate (MDI) with diol monomer N-benzyloxycarbonyl-β,β′-dihydroxyethylamine (CbzHEA). Selective N-protection of N-benzyloxycarbonyloxy-5-norbornene-2,3-bicarboximide (CbzONB) with β,β′-dihydroxyethylamine (HEA) gave the N-Cbz protected diol monomer HEA. The related monomer model compounds were also prepared by the same methods.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260616
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    Peroxide-catalyzed grafting of maleic anhydride onto molten polyethylene in the presence of polar organic compounds (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1189-1198 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The crosslinking of LDPE resulting from reaction with dicumyl peroxide at 180°C is increased in the presence of maleic anhydride (MAH). The presence of electron-donating nitrogen-containing compounds (amides, lactams, disubstituted aromatic amines, and amine oxides), phosphorous-containing compounds (phosphites, phosphates, phosphonates, phosphoramides, and phosphine oxides) and sulfur-containing compounds (sulfoxides, aryl disulfides, and thiazyl disulfides) which inhibit the homopolymerization of MAH but not that of methyl methacrylate, prevents crosslinking and yields soluble PE containing MAH units. Crosslinking, due to coupling of PE· macroradicals formed by hydrogen abstraction from PE by excited MAH, is prevented by electron donation from the additive to the MAH+ cation which is present in the MAH+-MAH excimer as well as in the excimer which is appended to the PE.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260419
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    Mass transfer of oxygen in poly(2-hydroxyethyl methacrylate) (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1179-1188 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The diffusion coefficient of oxygen in poly(2-hydroxyethyl methacrylate) has been explicitly measured using an optical technique based on fluorescence quenching. This measurement represents the first explicit determination of DO2 in PHEMA. A diffusion coefficient of oxygen in PHEMA of 1.36 × 10-7 cm2/s at 20°C was obtained from this measurement. This value is shown to agree well with permeability data for PHEMA, the free volume theory of diffusion, and with values of DO2 that have been explicitly measured in other methacrylate hydrogels.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260418
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    Surface modification of polymers. I. Vapour phase photografting with acrylic acid (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2099-2111 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Surfaces of low density polyethylene, high density polyethylene, and polystyrene have been modified by grafting with acrylic acid. Benzophenone and acrylic acid in the vapor phase were UV-irradiated in the presence of a polymer substrate. Grafting with acrylic acid took place in a thin layer on the surface, thus increasing the wettability of the polymer. After 5 min of irradiation, the contact angle against water had decreased to 20° for polystyrene and 50° for the polyethylene samples. ESCA measurements on samples irradiated for 5 min showed a 90% poly(acrylic acid) coverage of the surface for polystyrene, 63% for low density polyethylene, and 56% for high density polyethylene. Acetone or ethanol were used as carriers of monomer and initiator. Acetone was able to initiate grafting and was found to promote and direct grafting to the surface. The stability of the acrylic acid grafted surfaces was studied by contact angle measurements and ESCA. At room temperature, the grafted layer is confined to the surface, but when the material was heated in air the surface was reshaped into a hydrophobic one. The process was reversible. In aqueous surroundings at elevated temperatures the hydrophilic character of the surface was restored.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260809
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    Synthesis of polyamides based on 1,8-diamino-p-menthane (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2859-2862 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261023
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    The surface photopolymerization of perfluorobenzene and photocopolymerization of perfluorobenzene/benzene: A possible model for plasma polymerization (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2873-2880 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: ESCA has been used to characterize films deposited from perfluorobenzene and perfluorobenzene/benzene vapors during plasma polymerization and irradiation with vacuum ultraviolet light. The films deposited by both methods are shown to be essentially the same. This indicates that similar electronically excited states are involved in the formation of the precursors to deposition in both methods and that reaction mechanisms involving ions do not need to be considered for the plasma polymerization of the monomers investigated.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261101
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    Synthesis and characterization of phenyl-pendant aromatic polythiazoles from bis-α-bromophenylacetyl compounds and dithioamides (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2899-2905 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Novel phenyl-pendant aromatic polythiazoles having inherent viscosities of 0.3-1.3 dL/g were synthesized by the solution polycondensation of bis[4-(α-bromophenylacetyl)phenyl] ether with aromatic dithioamides or dithiooxamide in dimethylformamide at 60°C. The polythiazole having m-phenylene linkage was readily soluble in chloroform and m-cresol, and transparent flexible film could be cast from the chloroform solution. Glass transition temperatures of these polythiazoles were in the range of 210-250°C. They started to decompose at about 500°C in air with 10% weight loss being recorded at around 570°C.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261103
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    Preparation and properties of aromatic polyamides and copolyamides from phenylindanedicarboxylic acid and aromatic diamines (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2917-2922 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Aromatic polyamides (aramids) having inherent viscosities of 0.5-1.10 dL/g were prepared by the direct polycondensation of 1,1,3-trimethyl-3-(4-carboxyphenyl)indane-5-carboxylic acid with various aromatic diamines using triphenyl phosphite and pyridine as the condensing agents. Copolyamides were also prepared by a similar procedure from a mixture of the phenylindane diacid, terephthalic acid, and p-phenylenediamine. Almost all of the aramids were soluble in a variety of solvents such as N-methyl-2-pyrrolidone, pyridine, and m-cresol, and afforded transparent and tough films by the solution casting. These aramids and copolyamides had glass transition temperatures in the range of 290-355°C, and started to lose weight at 340°C in air.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/pola.1988.080261105
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    Polycondensation of bis(p-nitrophenyl) β-truxinate with diamine (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2941-2952 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Model reaction of bis(4-nitrophenyl) β-truxinate (BNPT) with aliphatic amines proceeded quantitatively at room temperature. Accordingly, polycondensation of BNPT with various diamines was carried out at room temperature or 80°C. During the polycondensation of BNPT with diamines, the precipitation of polymer or the observed gelation of polymerization solution occurred, which may limit the molecular weight of the polymer. On the other hand, the reaction of BNPT with 1,3-(4-piperidyl)propane (DPP) proceeded homogeneously to give the polymer with relatively high molecular weight, and the obtained polyamide (P-1e) showed excellent solubility in many solvents. The study of TG and DTA indicated that the obtained polymers were stable at lower temperature than around 270°C. The polymer prepared from the polycondensation of BNPT with hexamethylenediamine showed melting point and decomposition due to the imidation at 282°C. The photochemical reaction of these polymers was carried out in the film state. The irradiation of 254 nm light caused an absorption at 272 nm to appear and the molecular weight to decrease. This meant that the scission of cyclobutane ring in the main chain occurred to give cinnamamide structures. Also, the absorption at 272 nm decreased by the irradiation of 302.5 nm light. However, the UV spectrum of irradiated polymer did not agree with that of the original polymer. These results suggested that the dimerization of the resulting cinnamamide moieties occurred in the competition of their trans-cis-isomerization. On the other hand, the rate of scission of cyclobutane ring of P-1e was faster than that of the corresponding polyamide containing α-truxillamide structure.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261107
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    Synthesis of fluorine-containing graft copolyamides by using condensation-type macromonomers (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2991-2996 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Fluorine-containing graft copolyamides were prepared from condensation-type macromonomers. Dicarboxyl-terminated poly(perfluoroalkylethyl acrylate) was prepared by radical chain transfer polymerization and copolycondensed with diamines and dicarboxylic acids in the presence of triphenylphosphine and pyridine. Nylon-6 films containing various amounts of the resulting graft copolyamides were obtained by heat pressing. Only 5 wt % of graft copolymers were sufficient to make nylon-6 surfaces water repellent.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261110
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  • 75
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    Activation and racemization of trifluoroacetate esters in the cationic polymerization of styrenePresented in part at the American Chemical Society Meeting, New Orleans, LA, September 1987. (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 3031-3042 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1-Phenylethyl trifluoroacetate (1) does not react directly with styrene but it is readily incorporated into polymer chains in the presence of an excess of trifluoroacetic acid. The proportion of the nondeuterated 1-phenylethyl end groups in the polymerization of deuterated styrene coinitiated with the acid was much higher than the proportion of the end groups formed by direct incorporation of the acidic protons ([CH3—CHPh—CD2—CDPh— …] 〉 [HCD2—CDPh—CH2—CDPh— …]). The racemization of the optically active ester-(pseudo-first order rate constant at [HA]0 = 0.79 mol/L at 20°C equals kR = 1.7 × 10-4 S-1) is more rapid than the incorporation of the ester into polymer chains (kE = 1.5 × 10-4 mol-1 Ls-1, [M]0 〈 0.4 mol L-1, i.e., kR 〉 kE · [M]). These results and the complete loss of the optical activity in the final polymer indicate that the ester is activated by the acid but it is incorporated into polymer chain via ionic intermediates.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261113
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  • 76
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    Synthesis and characterization of a multiblock copolymer of poly(N-isovaleryl ethyleneimine) and poly(ethylene glycol) (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 3043-3069 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Block copolymers of poly(N-isovaleryl ethyleneimine) (PiVEI) and poly(ethylene glycol) (PEG) were synthesized by coupling previously prepared blocks of PEG ditosylate with the dianion of the dihydroxy PiVEI. On the average four blocks coupled together to form the final block polymer. The PiVEI blocks crystallized with the same melting points as in the homopolymer. This restricted the mobility of the PEG blocks and they did not crystallize unless cooled well below room temperature. The mechanical properties of cast films were quite good with a tensile strength of 77 kg/cm2 and an elongation of 120%. The swelling of unoriented and oriented films with water was studied. The unoriented polymer absorbed about its own volume of water, even though PEG comprised only 40% of the total polymer.
    Additional Material: 17 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261114
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  • 77
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    Metallocene-methylaluminoxane catalysts for olefin polymerization. I. Trimethylaluminum as coactivator (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 3089-3102 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ethylene was polymerized by Cp2ZrCl2-methylaluminoxane (MAO) catalysts where a portion of the MAO was replaced with trimethyl aluminum (TMA). At a total Al to Zr ratio of 1070, there is neither appreciable loss of productivity nor change in polymerization profile for TMA/MAO ≤ 10. The productivity is reduced only by two- to three-fold for TMA/MAO ≤ 100 accompanied by a 10 min induction period. Aging of this catalyst did not affect the induction period, but improves its productivity. The kinetic isotope effect for radiolabeling with tritiated methanol is 2.0. About 40% of the Zr is active for the catalyst with {99 [TMA] + 1[MAO]} to Zr ratio of 100. The rate constants for propagation and chain transfer were obtained. The mechanisms for the mixed TMA and MAO cocatalyst system are discussed. The results of this work have important practical significance. MAO is a hazardous material to synthesize and only in low yields. The replacement of 〉 90% of MAO with TMA represents a substantial saving since as much as 0.1M of the former is commonly used for a polymerization.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261117
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  • 78
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    Polystyrenes with p-oligo-siloxane, silane, germanosiloxane, germane, or stannane as p-substituents as materials for oxygen permeable membranes (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1307-1314 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The title polymers were synthesized and the oxygen permeation behavior through the polymer films were studied. The oligodimethylsilane-substituted polystyrenes showed a little low Po2 compared with the oligodimethylsiloxane-substituted polystyrenes. The important role of trimethylsiloxyl group in permeation was suggested.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260505
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  • 79
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    Mechanism of thermal degradation of poly(alkyl acrylate)s using pyrolysis gas chromatography mass spectrometry (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1315-1322 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The pyrolyses of homologous poly(alkyl acrylate)s is reported with identification of the major pyrolyses products. A mechanism involving random homolytic scission of the chain followed by a series of intermolecular and intramolecular transfer reactions has been proposed for poly(methyl acrylate) by Cameron and Kane and further developed by Haken, Ho, Houghton, and Gunawan. This mechanism is demonstrated to be generally applicable to the poly(n-alkyl acrylate)s. Reaction mechanisms are postulated for the various products produced and ion fragmentation mechanisms for the mass spectra produced are shown.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260506
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  • 80
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    Chemical release control: Schiff bases of vinylbenzaldehyde and functional amines (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1335-1341 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Schiff base (SB) monomers of vinylbenzaldehyde with functional amines were prepared. Copolymers of SB monomers with N-vinyl-2-pyrrolidone soluble in aqueous solutions were obtained in most cases. However, p-aminobenzenesulfonamide monomer resulted in gel formation. Thus, the reaction of vinylbenzaldehyde copolymer with the sulfonamide was used instead of the copolymerization. The hydrolytic behaviors of SB monomers and copolymers to liberate respective amines were structure dependent and, for most copolymers, the rates were lower than those of the corresponding monomers.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260508
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  • 81
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    Autoxidation kinetics of atactic polypropylene in bulk (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1323-1334 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the reaction between atactic polypropylene (APP) and oxygen in bulk at temperatures ranging from 170 to 210°C and oxygen partial pressures from 160 to 760 torr have been studied by thermal differential analysis. The reaction takes place in two successive steps, both giving hydroperoxide groups as product. Partial reaction orders with respect to APP and oxygen for the first step, which corresponds to the uncatalyzed attack of a C—H tertiary bond to give a hydroperoxide, are one and two, respectively. In the second step, interpreted as another attack on a tertiary C—H by oxygen, catalyzed by a neighboring hydroperoxide group, reaction orders are one and one-half for APP and oxygen, respectively. Activation parameters have been determined and a reaction sequence is proposed. Hydroperoxidated APP subsequently decomposes via a zero-order process giving methylketone groups as its main product. An interpretation of this process is also given.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260507
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  • 82
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    Synthesis and use of α-methoxyphenylmethylium hexachloroantimonate as a novel initiator for the polymerization of propylene oxide (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 3189-3198 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: α-Methoxyphenylmethylium hexachloroantimonate was prepared from α-methoxybenzyl chloride and antimony pentachloride at 0°C and isolated for the first time, and its visible and 1H-NMR spectra were measured. This salt was used as a novel initiator for the polymerization of propylene oxide (PO) in the temperature range -20 to 30°C with dichloromethane as solvent. PO polymerized spontaneously but a limit yield was observed. The microstructure of PO polymer is amorphous by 13C-NMR. The PO polymerization is thought to proceed in the conventional cationic mechanism on the basis of the polymerization behavior and the analyses of both the polymer structure and end groups attached to the PO polymer.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261206
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    The crosslinking of epoxy resins at interfaces. V. Amine-cured resins at carbon and graphite surfaces (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1377-1391 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The effects of carbon blacks, chopped carbon fibers, and crushed carbon fibers on the crosslinking chemistry of a diglycidyl epoxy resin/m-phenylenediamine system were examined by infrared (IR) spectroscopy and differential scanning calorimetry (DSC). The carbon and graphite surfaces were given oxidizing and reducing treatment to simulate the surface treatment of carbon fibers used in the manufacture of composites. The oxidized carbon surfaces initially accelerated epoxy-amine reactions but inhibited the later stages of the reaction such that the final extent of cure was reduced. The oxidized carbons also preferentially adsorbed the amine curing agent, resulting in a stoichiometric imbalance at the interface.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260511
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    Cure of epoxy resins with cyanoacetamides (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1361-1376 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Cyanoacetamides are a novel class of curing agents for epoxy resins. Since reaction products of epoxy compounds with cyanoacetamides have not yet been described, we investigated the reaction of phenyl-glycidylether (PGE) and N-isobutylcyanoacetamide (NICA) under the conditions of the epoxy cure (120-150°C). Twenty-two fractions of the reaction product have been separated by preparative TLC and characterized by FD and MS mass spectroscopy. The structures of 10 reaction product have been elucidated by MS, NMR, and IR techniques. They belong to the classes of cyclic urethanes, spiro-dilactones, cyclo-oxa-1-hepten-4-one-2, pyrimidones, aminocrotononitrile, and tertiary amine. This complex model reaction mixture does not enable us to propose a curing mechanism. However practical cure of Bisphenol A diglycidylether (BADGE) yields clear and tough solids with a glass transition temperature up to 200°C, good mechanical strength, and high adhesion to metal surface. Cyanoacetamides are latent hardeners requiring a curing initiator. Since N-4-chlorophenyl-N′-dimethylurea is a latent initiator, liquid, homogeneous, storage stable “one shot” systems can be formulated which harden quickly above 120°C. Heat aging properties of cured specimens are reported. A series of novel liquid, resinous, and crystalline cyanoacetamides and their potential as curing agent are described.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260510
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    Morphology of block copolyurethanes. III. Effect of polyether molecular weight on the mechanical properties of solvent cast films (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1393-1404 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A homologous series of copolyether-urethane-ureas were synthesized with polypropylene glycol segments having molecular weights of approximately 200, 400, 700, 1000, 2000, and 3000. These copolymers were characterized using tensile measurements and dynamic mechanical spectroscopy. The dynamic mechanical measurements at low frequencies (≤ 1 Hz) showed evidence of the existence of an α-relaxation process. This was attributed to constrained polyether segments located at the interfacial region between the hard urea segments and the soft polypropylene glycol segments.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260512
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  • 86
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    Bis- or tetra-maleimides of substituted s-triazines chain-extended by imide, amide, and urea groups for fire- and heat-resistant applications (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1405-1418 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Novel phosphorylated bismaleimides and nonphosphorylated tetramaleimides containing substituted s-triazine rings (chain-extended by imide, amide, or urea groups) were prepared and polymerized. These polymer precursors were prepared by reacting 2,4-bis(4-aminophenoxy)-6-diethoxyphosphinyl-s-triazine or 2,4,6-tris(4-aminophenoxy)-s-triazine with maleic anhydride in combination with a bridging agent such as pyromellitic or benzophenone tetracarboxylic dianhydride, terephthaloyl chloride, and tolylene diisocyanate. The structure of polymer precursors was confirmed by infrared (IR) and proton nuclear magnetic resonance (1H-NMR) spectroscopy and their curing behavior was investigated by differential thermal analysis (DTA). The phosphorylated bismaleimides were thermally polymerized at a lower temperature than did the corresponding nonphosphorylated tetramaleimides. Dynamic thermogravimetric analysis (TGA) showed that the nonphosphorylated and phosphorylated cured resins were stable up to 320-370 and 312-327°C, respectively, in nitrogen or air atmosphere. In addition, the latter afforded a relatively higher char yield. The relative thermal and thermooxidative stability of polymers with regard to the chemical structure of the bridging group was of the order imide 〉 amide 〉 urea. Upon isothermal aging the phosphorylated polymers exhibited a lower weight loss than did the corresponding nonphosphorylated polymers.
    Additional Material: 5 Ill.
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    URL: http://dx.doi.org/10.1002/pola.1988.080260513
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    Characterization of poly(carboxylic acid)/poly(ethylene oxide) blends formed through hydrogen bonding by spectroscopic and calorimetric analyses (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1419-1428 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The solid state of the complex between poly(acrylic acid) (PAA) and poly(ethylene oxide) (PEO), and that between poly(methacrylic acid) (PMAA) and PEO formed via hydrogen-bonding was studied by differential-scanning calorimetric (DSC) and by Fourier-transform infrared (FT-IR) spectroscopic measurements. Melting temperature Tm and the degree of the crystallinity Xc of PEO in the systems PAA (or PMAA)/PEO blends obtained from aqueous or dimethyl sulfoxide (DMSO) medium were measured in various unit mol % of PEO ([PEO]100/{[PAA(or PMAA)] + [PEO]}) where [ ] is the unit mole concentration. It was found that 50 unit mol % of PEO is a critical composition, which gives new evidence for the 1 : 1 complex formation between PAA (or PMAA) and PEO. From the FT-IR spectroscopic analysis in conjunction with DSC measurements we also found that the effects of solvent and of hydrophobic interaction (due to the α-methyl group of PMAA) are the important factors controlling the complexation in the solution and solid systems. These factors also affect the crystallization behavior and the microstructure of the PAA (or PMAA)/PEO blend in solid state.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260514
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    Investigation of the intramolecular structure of styrene-ethylmethacrylate copolymers by 1H- and 13C-NMR: Reassignment of 1H-NMR spectra (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1439-1456 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The compositions and sequence distributions of homogeneous styrene (S)-ethyl methacrylate (E) copolymers, obtained by low conversion solution polymerization have been studied by 1H- and 13C-NMR. A new set of peak triad assignments was proposed for the δ 2.1-4.2 ppm region in the 1H-NMR spectrum, whereby the reactivity ratios of rS = 0.59 and rE = 0.50 were used to establish this new assignment. The EEE and SSS blocks, present in these copolymers, have a high degree of syndiotacticity (σEE = 0.23, σSS = 0.39), whereas the ESE units are exhibiting a slight tendency toward isotacticity (σES = 0.66).
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260516
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    Reactivities of sulfur-centered radical toward polyisoprenes and polybutadienes studied by flash photolysis method (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1429-1438 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetic behavior of the thiyl radical in the solution containing polyisoprenes and polybutadienes has been studied by the flash photolysis method. For benzothiazole-2-thiyl radical, the addition rate constants toward these polymers and the model compounds of the polymers were evaluated. The relative reverse rate constants and equilibrium constants were also estimated. The addition rate constants decrease with an increase in the degree of polymerization; the ratio of the addition rate constant for polyisoprene (3.1 × 104 M-1 s-1 (in monomer unit); Mv = 674,000) to that for 2-methyl-2-butene (1.5 × 105 M-1 s-1) is about 1/5. This indicates that the polymer chain effect appears in the free-radical addition reaction. The relative reverse rate constants for the polymers are also smaller than those for 2-methyl-2-butene, suggesting a kind of polymer effects; i.e., it can be presumed that the bonded-thiyl radicals migrate very rapidly to the neighboring double bonds in the polymer. Significant differences in the rate parameters were observed between polyisoprene and polybutadiene, between cis- and trans-polyisoprenes, and between 1,4- and 1,2-polybutadienes.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260515
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  • 90
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    Processable, high temperature polymers from 1,4,5,8-tetrahydro-1,4;5,8-diepoxyanthracene and bis-dienes (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2907-2916 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1,4,5,8-tetrahydro-1,4;5,8-diepoxyanthracene reacts with various anthracene end-capped polyimide oligomers to form Diels-Alder cycloaddition copolymers. The polymers are soluble in common organic solvents, and have molecular weights of approximately 21000 to 32000. Interestingly, these resins exhibit lower weight loss in air than in nitrogen. This is suggested to be due to dehydration (loss of water ranges from 2 to 5%) at temperatures of 390 to 400°C to give thermooxidatively stable pentiptycene units along the polymer backbone. Because of their high softening points and good thermooxidative stability, the polymers have potential as processable, matrix resins for high temperature composite applications.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261104
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  • 91
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    Thermally reversible, covalently crosslinked polyphosphazenes (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2923-2939 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The concept of thermally reversible crosslinking was investigated by using poly[bis(trifluoroethoxy)phosphazenes] with different percentages of cyclopentadienylethoxy and dicyclopentadienyldiethoxy substituent groups. The resultant structures of these polymers are discussed and the phenomenon of reversible crosslinking is demonstrated by means of a DSC study and solubility behavior.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261106
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  • 92
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    Parylene C at subambient temperatures (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2953-2971 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Dependence of Parylene C deposition rate on dimer sublimation temperature, inert gas pressure, substrate temperature, and mass of dimer has been investigated. It was found that Parylene C deposition proceeds best at ambient temperature and produces film of optimum performance. Opacity in the film results from its rough morphology and not from the incorporation of the dimer in the film as is normally thought. This was evidenced from scanning electron microscopy and from an estimation of the volatile contents of the Parylene C films. Deposition of Parylene C at liquid nitrogen temperature proceeds via trapping of active monomer species followed by spontaneous polymerization. A quantitative study of the monomer to polymer transition by ESR spectroscopy is presented.
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261108
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  • 93
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    Electronic Resource
    Superactive and stereospecific catalysts. II. Kinetics of propylene polymerizations (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2973-2989 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of propylene polymerization by superactive CH-catalyst prepared from toluene solution of MgCl2 · EH/PA/TiCl4-TEA/PES was investigated. The results are compared with CW-catalyst prepared from crystalline MgCl2/EB/PC/TEA/TiCl4-TEA/MPT (abbreviations given in the text). The former is four times more active than the latter and produces more isotactic polypropylene. The CH-catalyst has 25% of the Ti as isospecific sites as compared to 6.7% for the CW-catalysts. These sites have the same rate constant of propagation so that the higher polymerization activity of the CH-catalyst is attributable simply to a greater number of active sites. Differences in the kinetics of deactivation and of chain transfer for the two catalysts are described.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261109
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  • 94
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    Electronic Resource
    Synthesis and characterization of urethane polymers containing 2,2′-biimidazole (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 3015-3029 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A heterocyclic nitrogen-containing system having substituent primary diol function, i.e., 1,1′-dihydroxethyl-2,2′-biimidazole (I), has been prepared and used to synthesize a series of new polyurethanes based on aromatic diisocyanates (TDI, MDI). Variation of solution polymerization parameters permitted the isolation and infrared, NMR, molecular weight, and thermal characterization of polymeric materials. Isolated polymers exhibit a linear structure and have Tg (150-170°C) and thermal stability (205-250°C for 20% weight loss) properties comparable to other typical urethane polymers. Zn2+ complexation was indicated by shifts in the imidazole ringmode infrared vibrational bands at 917 and 1133 cm-1 to higher frequencies.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261112
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  • 95
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    Electronic Resource
    Synthesis and characterization of monomers and polymers of acrylated phosphonate esters derived from glycerol, D-mannitol, D-sorbitol, pentaerythritol, and dipentaerythritol (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2997-3014 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Phosphonic acid ester derivatives of glycerol, D-mannitol, D-sorbitol, pentaerythritol, and dipentaerythritol have been synthesized by transacetalation reactions with diethyl 2,2-diethoxyethylphosphonate. These phosphonated derivatives of polyols and carbohydrates have been esterified to from the corresponding methacrylates. All these compounds have been characterized on the basis of their elemental analysis and spectroscopic (infrared including FT-IR, 1H-, 13C-, 31P-NMR, and mass) methods. Transacetalation reactions with dialkyl 2,2-dialkoxyethylphosphonate lead to the synthesis of 1,3-dioxane derivatives in the case of D-mannitol, pentaerythritol, and dipentaerythritol, whereas a mixture of both 1,3-dioxane and 1,3-dioxolane derivatives is obtained with D-sorbitol and glycerol. The methacrylates of phosphonylated polyol derivatives show the capacity to dissolve and interact with metal salts such as bismuth bromide and uranyl nitrate. Some of the polymers obtained from these monomers have been characterized on the basis of their spectral and thermal (differential scanning calorimetry) properties.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261111
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  • 96
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    Electronic Resource
    Thermotropic liquid crystallinity of copoly(ester-amides) prepared by the direct polycondensation with diphenyl chlorophosphate in pyridine (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 3071-3076 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Copolycondensation of isophthalic (IPA) and terephthalic (TPA) acids, methylhydroquinone (MeHQ), and aromatic diamines with diphenyl chlorophosphate (DPCP) in pyridine were investigated. The resulting copoly(ester-amides) showed optical anisotropy, which was discussed in terms of the ester and amide sequence lengths in the copolymers. The temperature above which the anisotropy was observed varied in the 225 to 300°C range by changing addition time of a mixture of MeHQ and diamines, initial reaction with MeHQ, and the further reaction with diamines.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261115
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    A novel reactive monomer: Preparation and radical polymerization of allenyl glycidyl ether (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 3119-3121 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261119
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  • 98
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    Electronic Resource
    Synthesis and liquid crystalline properties of thermotropic homo- and copolycarbonates (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 3077-3088 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Nondirect-type thermotropic homo- and copolycarbonates which have flexible spacers between mesogens and carbonate linkages (-mesogenic unit-flexible spacer-carbonate link-flexible spacer-) were derived from dihydroxyalkyleneoxy derivatives containing biphenyl, i.e., 4,4′-bis (ω-hydroxyalkyleneoxy)biphenyl (Ia and Ib), as mesogens and the structure-liquid crystallinity relationships were evaluated by thermal analysis and with polarizing microscope.Homopolycarbonates with high molecular weight were prepared from (Ia) and (Ib), and alkylene diphenyl dicarbonates (II) by melt polycondensation. The polymers form mesomorphic phases and exhibit linear decrease of phase-transition temperatures with increment of alkylene spacer lengths without displaying odd-even number fluctuations. They show lower phase-transition temperatures and narrower mesomorphic temperature ranges than analogous direct-type (-mesogenic unit-functional group-flexible spacer-) biphenyl-containing polycarbonates \documentclass{article}\pagestyle{empty}\begin{document}$ \rlap{--} ({\rm OMOC}({\rm O}){\rm O}({\rm CH}_2)_m {\rm OC}({\rm O})\rlap{--})_x $\end{document} and polyesters \documentclass{article}\pagestyle{empty}\begin{document}$ \rlap{--} ({\rm OMOC}({\rm O})({\rm CH}_2)_m {\rm C}({\rm O})\rlap{--})_x $\end{document}, but have wider temperature ranges than nondirect-type (-mesogenic unit-flexible spacer-functional group-flexible spacer-) biphenyl-containing polyesters \documentclass{article}\pagestyle{empty}\begin{document}$ \rlap{--} ({\rm O}({\rm CH}_2)_n {\rm OMO}({\rm CH}_2)_n {\rm OC}({\rm O})({\rm CH}_2)_m {\rm C}({\rm O})\rlap{--})_x $\end{document}. These results indicate that by the incorporation of alkylene segments between mesogens and carbonate linkages the polymers having reasonable phase-transition temperatures and wider mesophasic temperature ranges can be obtained. Copolycarbonates were prepared from mixtures of (Ib) and 1,4-bis(2-hydroxyethyleneoxy)benzene (IV), nonmesogenic moiety, taken in definite molar ratio in feed and (II) (m = 2 and 4). These copolymers except polymers having only nonmesogenic moiety show liquid crystalline mesophases and have wider phase-transition temperature ranges than the homopolymers. Maximum temperature ranges are observed in the copolymers of composition ratio of 1 : 1. Stable mesophases can be obtained over the entire range of compositions, even though the copolymers contain nonmesogenic units in the backbones.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261116
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  • 99
    Electronic Resource
    Electronic Resource
    Further study of the direct polycondensation with phenylphosphonic dichloride in pyridine (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 3123-3126 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261120
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  • 100
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    Electronic Resource
    Chemical modification of poly(substituted-acetylene). III. Synthesis and gas permeability of poly(1-phenyl-1-propyne)/poly(dimethylsiloxane) graft copolymer (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 3131-3137 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080261122
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