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  • 1985-1989  (480)
  • 1970-1974  (2,547)
  • Physics  (3,027)
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    The visual computer 2 (1986), S. 159-163 
    ISSN: 1432-2315
    Keywords: Education ; Animation ; Computer graphics ; Physics ; Solar system
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Notes: Abstract Within the Jet Propulsion Laboratory in Pasadena, California, state of the art computer graphics animation is done in the Computer Graphics Laboratory. The topics of the animations cover many scientific disciplines. Specific features of the system developed there, both hardware and software, are discussed. The prime mover of the effort is Dr. James F. Blinn of Pasadena; his role and experiences are elaborated. Their current largest project is The Mechanical Universe; the system is used for its production.
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  • 2
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 159-168 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Oligomers of 4-vinylpyridine were prepared by reaction in vacuo of 4-vinylpyridine with lithio-4-ethylpyridine at -78°C, followed by reaction with CH3I(13CH3I) or CH3OH. The stereochemistry was studied by NMR and GC. Methylation and the addition of 4-vinylpyridine occurred in a stereochemically nonselective manner. The data also indicated that in contrast to the oligomerization of 2-vinylpyridine the stereoisomeric meso and racemic 4-pyridyl carbanions propagated with equal reaction rates. The stereochemistry was readily explained by an absence of coordination of the Li ion by the nitrogen of the penultimate pyridine ring observed in the corresponding oligomerization of 2-vinylpyridine.
    Additional Material: 5 Ill.
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  • 3
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 635-648 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A comparative ESR study of low-temperature photolysis at 77 and 4.2 K of isotactic polypropylene, preoxidized under controlled conditions, and of 2.6.8 trimethylnonane-4-one as a model compound of the inchain PP ketones —CH2COCH2— is presented. The results show conclusively that the ESR spectra of low-temperature PP photolysis reported in the literature arise from the decomposition of tertiary hydroperoxides, whereas the contribution by the Norrish I photolytic cleavage of ketones is of minor importance; the relative efficiency of radical production at 77 K (λ ≥ 300 nm) by both types of photoactive compound has been measured by ESR and found to be about 15 times greater for the hydroperoxides. The mechanism of solid-state photolysis of PP hydroperoxides is dominated by the nearly complete decay of excited alkoxyls during the photolytic events that yield the chain end radicals —CH(CH3)CH2· by β scission (87.8%) and the inchain radicals —CH2C(CH3)CH2— by hydrogen abstraction (10.4%). The low yield of methyl radicals detected (1.8%) and their delayed appearance strongly suggest that these species are of secondary origin and that the decomposition of alkoxyls via C—CH3 scission is of negligible importance. From the ESR anisotropy of the deliberately prepared peroxyradicals —CH(CH3)CH2O2· and —CH2C(CH3)(O2)CH2— evidence of the misalignment of terminal chain segments following scission of alkoxyls at 77 K was obtained. An unexpected result of the measurements at 4.2 K is represented by the identification of a clear signal by H atoms: the H atoms apparently are not trapped in perprotiated matrices, even at 4.2 K, because of their unusually high reactivity toward the hydrogen abstraction assisted by tunneling effects.
    Additional Material: 6 Ill.
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  • 4
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 787-793 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly[S-(2-9′-acridinylethyl)-L-cysteine] (5) was synthesized by the N-carboxy anhydride procedure. It was converted to the trifluoroacetic acid salt (6), which was treated with LiTCNQ in methanol to give the TCNQ anion radical salt (7). 7 showed electrical conductivity of 10-8 S/cm at 295 K.
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  • 5
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 761-786 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: More than a hundred propylene polymerizations were carried out with the CW catalyst (our particular MgCl2/ethylbenzoate/p-cresol/AlEt3/TiCl4 supported high mileage catalyst). Highest I.I. index (% yield of boiling heptane insoluble product) of 96.2 ± 0.9 was obtained at [Ti] = 2.4 × 10-4 M, A/T (amount of AlEt3 with 0.33 equivalent of methyl-p-toluate to amount of Ti in the catalyst) = 167 at 50°C. The I.I. values became lower when any one of these variables was changed. The I.I. values did not change with time of polymerization, indicating that both stereospecific and nonstereospecific sites were produced at the same time and polymerized monomers during the course of a polymerization. Estimates of maximum active site concentrations, [Ti*]0,Because of the complexity of the catalyst system, the active sites are designated as follows: [Ti*], active sites of all kinds at a given time; [Ti*]0 active sites of all kinds at time zero; [Ti1*], active sites of the first kind formed initially upon activation; [Ti2], active sites of the second kind, which were transformed from the former, and are responsible for olefin polymerization after the initial phase of rapid decay of activity; [Ti*]i, stereospecific active sites; [Ti*]a, nonstereospecific active sites, and [Ti*]t = [Ti*]i + [Ti*]a Similarly, the subscripts 1 and 2 for the various rate constants refer to active sites Ti1* and Ti2*, respectively. Finally [Ti] is the concentration of total titanium in the amount of catalyst used. [Ti-P] is the titanium polymer bond concentration as determined by 14CO tagging; [Ti-P] (1 h) and [Ti-P] (48 h) are the values obtained with indicated time of contact of 14CO with the polymerization mixture in the obsence of monomer. were obtained from a variation of vn-1 versus t-1. The values of [Ti*]0.i and [Ti*]0,a for the stereospecific and nonstereospecific sites, respectively, are in excellent agreement with those values of [MPB]0 (metal polymer bond concentrations at t = 0) determined earlier by radiotagging with tritiated methanol. The rate of formation of [Ti*]1 (the initial active site) is first order with respect to [Ti] and [A] with an activation energy of 12 kcal mol-1 where [A] is the AlEt3 concentration. The rate constants of propagation at 50°C are kp,i ∼ 160M-1s-1 and kp,a ∼ 11M-1s-1. The activation energy for the stereospecific propagation is about 4.1 kcal mol-1. At 50°C the rate of polymerization decreases according to second order kinetics suggesting bimolecular processes which transform one-half to one-fourth of the Ti1* site to Ti2* types depending upon experimental conditions, while the remainder decay to inactive species. The values of kt1 lie between 19 and 61M-1s-1. These processes are more complicated at 70°C involving two consecutive reactions; at low [A], the data fits better with first order decay kinetics. Comparison of the [Ti2*] values and the values of [Ti-P] obtained by 14CO tagging suggests that CO reacts primarily with the Ti2* sites and very little with the initially formed Ti1* sites. The Ti2* sites are slightly less active than the Ti1* sites having kp2,i ∼ 86M-1s-1 and kp2,a ∼ 7M-1s-1 at 50°C.
    Additional Material: 20 Ill.
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  • 6
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 813-828 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of methyl methacrylate within solid matrices of stereoregular poly(methyl methacrylate) has been studied by proton NMR and wide angle X-ray diffraction. The semi-crystalline isotactic (i-) PMMA matrix was synthesized in the laboratory by anionic polymerization initiated by phenylmagnesium bromide, and the syndiotactic (s-) PMMA matrix was synthesized through a Ziegler-Natta reaction. Matrix polymerization of the monomer was initiated through the redox activation of benzoyl peroxide with N,N-dimethyl-p-toluidine. NMR measurements of triad distributions in matrix-polymerized chains suggest that the well-known stereospecific replica polymerization in PMMA (syndiotactic sequences promote isotactic sequences and vice versa) plays only a limited role in the systems studied. Experimental results indicate that chains grown within the i-PMMA or s-PMMA solid matrices have greater degrees of configurational disorder. The greater concentration of atactic triads in these chains could be the result of limited free volume or steric effects during polymerization in a highly condensed environment. X-ray diffraction studies of solution cast blends of isotactic PMMA and PMMA with conventional tacticity reveal some crystallinity with a structure characteristic of the stereocomplex formed by isotactic and syndiotactic PMMA from suitable solvents. Evidence was obtained for the presence of this complex in solidified mixtures of the i-PMMA solid matrix and liquid monomer. This observation is an example of special intermolecular structures that can form under conditions of in situ growth of chains within a pre-polymerized matrix.
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  • 7
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 829-841 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Metal powders were incorporated into various elastomers and the mixtures were subjected to intense shearing in air or a nitrogen atmosphere. The molecular weight after shearing was still relatively high, however; greater than 100 kg/mol. The elastomer was then dissolved and centrifuged to remove the metal particles and the solution was analyzed for reaction products. A strongly ultraviolet (UV)-absorbing species was formed by shearing a styrene-butadiene copolymer (SBR) with iron powder. The concentration increased with the concentration of iron powder in the mixture and the extent of shearing, and it was greater after shearing in a nitrogen atmosphere. These results are attributed to the direct reaction of macromolecular radicals, formed by shearing, with iron powder to yield an iron-polymer compound. Natural rubber (cis-polyisoprene), which absorbed 100-200 μg of iron per gram of polymer, was about as reactive as SBR. Polybutadiene was less reactive, and an ethylene-propylene copolymer did not react with or solubilize a significant amount of iron. Zinc was, in general, solubilized to a somewhat lesser degree than iron, whereas aluminum powder appeared to undergo virtually no reaction with sheared elastomers. The maximum extent of reaction (solubilization) was of the order of one metal atom per final polymer molecule, which was consistent with the proposed mechanism. Moreover, an analogous reaction took place between simple organic radicals and iron particles in suspension.
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  • 8
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 843-849 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1,4-Oxathian-2-one (1a) was prepared in high yield by oligomerization of methyl(2-hydroxyethyl)mercaptoacetate (3) followed by catalytic depolymerization in vacuo. A similar sequence starting with methyl(2-hydroxyethyl)sulfonylacetate (5) afforded the corresponding sulfone, 1,4-oxathian-2-one-4,4-dioxide (1c), however, 1,4-oxathian-2-one-4-oxide (1b) could not be obtained by this procedure. Ring opening melt polymerization of 1a and 1c afforded low molecular weight crystalline polyesters 2a and 2c. Oxidation of 2a with m-chloroperoxybenzoic acid produced the corresponding polyester 2b containing sulfoxide groups. Thermogravimetric analyses and visual observations indicated 2b to be thermally unstable relative to 2a and 2c.
    Additional Material: 1 Tab.
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  • 9
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 851-857 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Dissolving pulp and its partially xanthated derivative were grafted with styrene, using either the Fe2+-K2S2O8 redox system of potassium persulfate alone as initiators. The conversion of styrene to both copolymer and homopolymer was found to be influenced by agitator speed. The effect of stirring was much more pronounced with the xanthated substrate in that a welldefined conversion maximum was observed at the same agitation speed for both total polymer and copolymer. Grafting onto dissolving pulp with the redox initiator also showed a maximum, but a maximum total polymer and maximum copolymer were located at different agitator speeds. Grafting of styrene onto dissolving pulp initiated by potassium persulfate was almost independent of stirring in the 0-910 rpm range.
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  • 10
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 879-893 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Vinylsulfonylethyl (VSE) derivatives of the nucleic acid bases adenine, thymine, cytosine, and the nucleosides inosine and uridine have been prepared via a simple Michael reaction with divinyl sulfone. The VSE derivatives were grafted on a polyethyleneimine (PEI) backbone. PEI of different molecular weights (1400, 1800 and 50,000-100,000) were used and also two different molar ratios (1:1 and 1:2) of monomer to PEI were employed. From the 1H-NMR and elemental analysis, it appeared that in almost all instances the grafting was quantitative. In one case, both 1-VSE-thymine and 9-VSE-adenine were grafted on the same PEI backbone. Interactions between some of these polymers were investigated by UV spectroscopy. The expected complementary base pairing was observed only in DMSO-ethylene glycol solvent system but not in DMSO. The adenine polymer showed a one-to-one interaction with the thymine polymer.
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  • 11
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 901-904 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
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  • 12
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 193-214 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of acrylamide in inverse microemulsions stabilized by Aerosol OT emulsifier and initiated with azobisisobutyronitrile (AIBN) or potassium persulfate (K2S2O8) has been investigated. The inverse polyacrylamide latexes formed are clear and highly stable. A dilatometric technique was used to follow the conversion of monomer at T = 45°C. The rate of polymerization is first order with respect to initial monomer concentration in the presence of AIBN, and is 1.5 order with K2S2O8. An inverse relationship between molecular weight and emulsifier concentration is found which suggests participation of the emulsifier in the initiation reaction. This is confirmed by the independence of the molecular weight of polyacrylamide on the concentration of the initiators. High values of the rate of polymerization are obtained combined with high molecular weights (up to 107). An important and novel feature of this microemulsion process is that each final latex particle consists of one single molecule of polyacrylamide in a collapsed state. This suggests kinetics which do not follow the Smith and Ewart theory but are characterized by continuous particle nucleation.
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  • 13
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 255-259 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 6 Ill.
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  • 14
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 231-253 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The alkylation of catechol with (chloromethyl)styrene-divinylbenzene copolymer 1 produces the polymer-bound catechol 2, which upon reaction with a series of polyglycol dihalides affords macrocyclic polymeric benzo crown ethers 3, in fair yields. The alkylation of polybenzylamine 4 with polyglycol dihalides leads to diazapolymeric pseudocrown ethers 5. The degree of conversion of the catechol groups into macrocyclic ether groups and the residual concentration of diol groups were estimated from elemental analysis, weight-gain data, and the analysis of bis-2,4-dinitrophenyl derivatives of the residual diol groups. The ion-coordination patterns for the polymeric crowns were determined using distribution and column techniques. Equilibrium distribution values in methanol in the temperature range 20-60°C, for the perchlorate, thiocyanate, or bromide salts, have led to the following conclusions: (1) The spheric recognition patterns, typical of crown ethers in solution, are fully reproduced in the polymeric analogs. (2) The order of binding constants is K 〉 Cs 〉 Na 〉 Li for polymeric benzocrown-6 (3Hc) and benzocrown-8 (3Hd) and K 〉 Cs ≅ Na 〉 Li for polymeric benzocrown-4 (3Ha) and benzocrown-5 (3Hb). (3) The polymers bind alkali metal cations by two mechanisms: the residual diol groups by ion exchange mechanism, and the crown groups by a salt-coordination mechanism; the second mechanism is temperature-dependent. Consequently, a thermal increase of 40°C causes a spontaneous elution, by “thermal shock,” and a three-fold increase in the eluent of the original ion concentration. (4) Quantitative release of all the bound salt is observed.
    Additional Material: 8 Ill.
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  • 15
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 303-306 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Copolymerization of styrene and β-bromostyrene, by constant potential electrolysis, in 1,2-dichloroethane was achieved at various applied potentials. Effect of polymerization potential on the copolymer composition and the reactivity ratios was studied. Monomer reactivity ratios were determined by integrated Lewis-Mayo equation.
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  • 16
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 337-342 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(butadiene-b-styrene) copolymers containing a pure, 1,4-PB block have been synthesized by a “living” coordination process. The complete hydrogenation of the PB chain leads accordingly to a high-density polyethylene (HDPE) block. The emulsifying efficiency of such a copolymer (H-7) in HDPE/PS blends is compared with that of a previously reported poly(ethylene-butene-b-styrene) copolymer (SE-7) obtained by the PB hydrogenation of an anionically prepared PB-b-PS. Microscopy examinations demonstrate unambiguously the interfacial activity of both copolymers in HDPE/PS blends. The tensile mechanical properties of the blends are significantly but also differently modified by the two emulsifiers. The copolymer H-7 gives rise to the highest strengths, but, contrary to the copolymer SE-7, provides a poor ductility to the blends. This different behavior is assumed to result in part from the different characteristics of the hydrogenated PB blocks. The elastomeric HPB chain of SE-7 should form at the interface a more or less extended soft zone whereas a rigid interface would result from the cocrystallization of the HPB chain of H-7 with the HDPE homopolymer.
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  • 17
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 399-410 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(ethylene oxide/isoprene/styrene/isoprene/ethylene oxide) block copolymers were synthesized using potassium-napthalene catalyst in tetrahydrofuran. The dynamic and thermal properties and water absorption of these tri-block copolymers were determined and related to their bulk morphology.
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  • 18
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 411-427 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Laser-initiated polymerization of cyclohexene oxide in the presence of maleic anhydride was investigated. The influences of solvents laser irradiation time and the monomer feed ratio on the polymer yield and composition were evaluated. The rate of polymerization increased with an increase in the molar concentration of maleic anhydride in the monomer feed. Short irradiation times of 1-3 min duration gave very high yield of epoxy polymer (〉80% conversion). Infrared spectral studies of the polymer product indicated the formation of polyether linkage at lower levels of conversion and an adduct of polyether and maleic anhydride at higher polymer conversions. The quantitative chemical analyses results also showed similar results. The results indicated that the polymerization was initiated by the excited charge transfer complex between the electron donor, cyclohexane oxide, and the electron acceptor-maleic anhydride. In the initial stages of polymerization, cyclohexene oxide undergoes a cationic polymerization in the presence of the radical anion of maleic anhydride. Laser-initiated polymerization of cyclohexene oxide/maleic anhydride is several hundred times more efficient than UV-initiated polymerization, as measured by the energy absorbed by the polymer system.
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  • 19
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 479-488 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The influence of power and substrate temperature on the chemical composition of inductively coupled RF plasma-polymerized films of acrylonitrile was monitored by ESCA. At a substrate temperature of 20°C a minimum in nitrogen content as a function of power was observed for films deposited in the coil region. A maximum was observed for a substrate temperature of 150°C. When power was increased from 1 to ∼50 W a linear increase in nitrogen content was observed in the tail region at both substrate temperatures. A step function observed in the C1s and N1s core-level spectra is discussed in terms of extensive unsaturation being present in the films.
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  • 20
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1259-1265 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(2,5-dimethoxy-1,4-phenylene) was prepared by oxidative polymerization of p-dimethoxybenzene with aluminum chloride and copper(II) chloride in nitrobenzene under reduced pressure. The polymers obtained were soluble in sulfuric acid and fusible at 320°C. The intrinsic viscosity of the polymer was ca. 0.07 in sulfuric acid. Demethylation of methoxy groups did not occur during the polymerization.
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  • 21
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1283-1292 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Pullulan-g-poly(p-acetoxystyrene) (I) was prepared using ammonium persulfate (APS) as an initiator in dimethylsulfoxide (DMSO) solution. I was deacetylated by hydrazine hydrate to yield pullulan-g-poly(p-hydroxystyrene) (II). The degree of polymerization of the grafted poly(p-hydroxystyrene) chain (III) was 15-20. Despite the effective grafting (%), this method caused the degradation of pullulan. The number of branch polymer chains per pullulan molecule were evaluated to be 0.9 to 2.5 from number average molecular weights of the permethylated II and III. The glass transition temperature of II was higher than that of III, indicating that the polar hydroxyl groups of pullulan in the graft polymer caused an increase in the rigidity of the grafted polymer chains. Pullulan-g-poly(o-hydroxystyrene) and pullulan-g-poly(MMA) were also readily prepared by this method.
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  • 22
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1321-1332 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The preparations of new model polymers of polynucleotides with linear poly(vinyl alcohol) (PVA) backbones and an optically active nucleic acid base derivative as a pending side chain are described. (±)-, (+)-, and (-)-2-(thymin-1-yl)propionic acid were grafted onto PVA through ester bonds by direct coupling with dicyclohexylcarbodiimide (DCC) in the presence of highly active catalyst 4-pyrrolidinopyridine (PPY) to give optically active graft polymers. The corresponding monomer and dimer models have been prepared.
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  • 23
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1343-1360 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A microstructure analysis of polychloroprenes by 1H and 13C NMR produced slightly different results which, however, are in good agreement. The main uncertainty concerned the assignment of the 1,4-cis and trans head-to-head and tail-to-tail additions. In the (+ 12, +70°C) region of polymerization temperatures the principal addition mode was 1,4. An increase in the polymerization temperature to 70°C increased the abnormal head-to-head, tail-to-tail additions, and 1,4-cis additions (6-7%), and all vinyl structures that were not higher than 2-3% were equally distributed between 1,2 and 3,4. Under the experimental conditions used in this study no isomerized vinyl structures were found. As in all radical polymerizations the influence of temperature on the propagation mechanisms, namely, the addition modes, was relatively weak, but because of the great number of possible addition modes in microstructure - physicomechanical relationships variations in the microstructure must be taken into account. Only 1H and 13C NMR are capable of determining these variations quantitatively.
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  • 24
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1361-1367 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A sulfonium salt derived from tosyl chloride and N-methylimidazole was successfully used as an effective condensing agent for the preparation of high-molecular-weight aromatic polyesters by the direct polycondensation of aromatic dicarboxylic acids and bisphenols. Conditions for the formation of the sulfonium salt and of the reaction of the salt with dicarboxylic acids favorable for the polycondensation were examined. Thermal property of a polymer was investigated in terms of random sequences of monomer in the polymer backbone. Preparation of a polyamide and a polyesteramide was attempted with limited success.
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  • 25
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1407-1419 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Benzophenone (BP)-sensitized photopolymerization of methyl methacrylate (MMA) in near UV/visible light was studied at 40°C using dimethylaniline maleic acid (DMA - MA) combination as the photoinitiator. An instantaneous 1:1 complexation between DMA and MA takes place when they are mixed together in acetonitrile. Also, instantaneous complex formation occurs between DMA and MMA and between MA and MMA when they are dissolved in MMA in low concentrations, separately. Interestingly, when equimolar proportions of DMA and MA are mixed together in MMA, there is indication for further instantaneous complexation between (DMA - MMA) complex and (MA - MMA) complex forming the actual initiating species in the photopolymerization system. Initiator exponent was 0.28 and monomer exponent varied between 0.0 to 1.8 depending on the nature of the solvent and range of dilution used. Analysis of kinetic data indicates a free radical mechanism for the polymerization with initiator-dependent termination. Chain termination via degradative initiator transfer is quite significant; but the degradative effect becomes much less prominent in the higher range of initiator concentration indicating that the reinitiation reaction following the initiator transfer process assumes more proportionate significance as the initiator concentration is increased, probably as a result of higher reinitiation efficiency. Polymers obtained gave evidence for the incorporation of aromatic (amine) end groups in them.
    Additional Material: 10 Ill.
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  • 26
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of fluorene with various chloromethylating reagents (methylene chloride, methoxyacetyl chloride, and chloromethyl methyl ether) in the presence of aluminum chloride was studied. The products that were obtained were insoluble, infusible, colored powders which contain a low concentration of aromatic radicals. Each of the polymers is composed predominantly of fluorene nuclei bridged at the 2 and 7 positions by methylene groups. In addition, the materials possess varying amounts of crosslinked and ring-fused moieties. Based on physical and spectral properties and reaction stoichiometry, the fluorene/methylene chloride polymer is the most highly crosslinked of the three. The fluorene/methoxyacetyl chloride and fluorene/chloromethyl methyl ether polymers are similar to each other in most respects.
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  • 27
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1455-1467 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A study has been made of a catalyst system comprising the heptane-soluble magnesium and titanium compounds in combination with an organoaluminum compound for ethylene polymerization at a high temperature. The productivity for ethylene polymerization of the catalyst system, n-butylethyl magnesium (BEM)-2-ethyl hexanol (C8H17OH)-tetra-n-butoxytitanium[Ti(OBu)4]/diethyl aluminum chloride (DEAC) is higher than for MgCl2-Cl2-C8H17 OHTi(OBu)4/DEAC and much higher than MgCl2-Ti(OBu)4/DEAC. The nature of the three different catalyst systems have been discussed in comparison with experimental data on polymerization behavior and the data of the elemental and x-ray diffraction analysis of the solid products obtained from the reactions between the catalyst components.
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  • 28
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1477-1491 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The influence of the N-alkyl group of tertiary hindered amines on the photostabilization of polymers was studied. The photostabilizing effects of the tertiary amine derivatives of 4-benzoyloxy-2,2,6,6-tetramethylpiperidine (1a) in polypropylene were compared. All tertiary amine derivatives having α-H to hindered N showed higher effectiveness than 1a. Model liquid phase photoxidations were carried out by irradiating (UV-lamp) the solutions of tertiary hindered amines containing tert-butyl hydroperoxide as a photoinitiator. The tertiary hindered amines were oxidized more easily than corresponding parent hindered amine and converted to the parent amine, which was identified as its salt, resulting from the carboxylic acid produced from the N-alkyl group by oxidation. The thermal reaction of the tertiary hindered amines with tert-butyl hydroperoxide was also studied in the liquid phase. The tertiary hindered amines decomposed tert-butyl hydroperoxide more rapidly than the parent secondary hindered amine, and generated the parent amine. It was also found that the photostabilizing effects of tertiary hindered amines for polyolefins were higher than that of the parent secondary hindered amine.
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  • 29
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1517-1526 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: p-Styrenesulfonate esters of primary and secondary perfume alcohols and phenols, including citronellol, 1-menthol, borneol, β-phenethyl alcohol, eugenol, p-anisyl alcohol, cinnamyl alcohol, and geraniol, and herbicide alcohols such as 2,4-dichloro- and 2,4,5-trichlorophenoxy-ethanols were synthesized using p-styrenesulfonyl chloride in the presence of bases such as pyridine, triethylamine, sodium hydrogen carbonate, and sodium hydride. The hydrolytic behavior of sulfonate ester monomers and their copolymers with N-vinyl-2-pyrrolidone to liberate perfume and herbicide alcohols was structure-dependent, thereby affording chemical release control.
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  • 30
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1527-1535 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Some hindered amine polymers containing 2,2,6,6-tetramethylpiperidine structure were synthesized. A new monomer, 4-O-vinylbenzyl-2,2,6,6-tetramethylpiperidine, was homopolymerized and copolymerized with some vinyl monomers in the presence of AIBN as an initiator. The obtained amine polymers were oxidized with hydrogen peroxide to obtain the polymers having nitroxyl radical moiety.
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  • 31
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1551-1568 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new method of block polymer preparation using combined anionic and free radical polymerization was investigated. In the method the first monomer was polymerized anionically. The resulting polymeric anions were then reacted with an episulfide to form a polymer with mercaptan end-groups. This mercapto - polymer was mixed with a second monomer(s) in an inert solvent for the free radical polymerization. Conventional free radical initiation methods were used to initiate the polymerization of the second monomer but because of the high chain transfer constant of the mercaptan groups, a large number of the free radical chains would grow from the first polymer to form a block polymer. Block polymers difficult or impossible to make by direct anionic polymerization can thus be prepared. Several block polymers, including the new thermoplastic elastomers, poly[(styrene-co-acrylonitrile)-b-butadiene-b-(styrene-co-acrylonitrile)] and poly(bromostyrene-b-butadiene-b-bromostyrene) were prepared by this method.
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  • 32
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1671-1675 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymeric azides reacted with triphenylphosphine to give the corresponding phosphine imines, which reacted with bases, aldehydes, and isocyanates to give amines, imines, and carbodiimides, respectively.
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  • 33
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1661-1670 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A heat-resistant polybismaleimide was obtained by the thermal polymerization of bis(maleimidophenoxy)- tetrakis(phenoxy)cyclotriphosphazene. The thermal stabilities of the polybismaleimide were evaluated in nitrogen and in air by thermogravimetric analysis. The polybismaleimide was stable to 340°C and has char yield of 70% at 800°C in nitrogen and of 60% at 700°C in air. The monomer bismaleimide was obtained by the reaction of bis(4-aminophenoxy)tetrakis(phenoxy)cyclotriphosphazene with maleic anhydride. The diamine was synthesized by a stepwise reaction of hexachlorocyclotriphosphazene with phenol and 4-nitrophenol to give bis(4-nitrophenoxy)tetrakis(phenoxy)cyclotriphosphazene and reducing the nitro groups. The structure of the cyclotriphosphazenes were characterized using Fourier transform infrared (IR), proton nuclear magnetic resonance (1H-NMR) spectroscopy, and elemental analysis.
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  • 34
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1009-1016 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Some two-, three- and four-component phenolic copolymers have been characterized, and mixed in definite stoichiometric proportions. The total amount of acidic and basic functional groups in a given weight of the copolymer mixture have been calculated from the characteristic parameters of the polymer components. Analysis of these copolymer mixtures by electrometric titration techniques revealed an excellent correlation between the calculated and observed values of functional groups.
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  • 35
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1707-1722 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Three types of isopropenylmetallocene monomers were synthesized and subjected to polymerization and copolymerization by cationic initiators; (1) isopropenylferrocene (IF); (2) (η5-isopropenylcyclopentadienyl)dicarbonylnitrosylmolybdenum (IDM); and (3) 1,1′-diisopropenylcyclopentadienylstannocene (DIS), and related derivatives of each. IF was synthesized by a three-step procedure involving the acetylation of ferrocene, conversion of the latter to 2-ferrocenyl-2-propanol, and dehydration of the carbinol. IF was homopolymerized under various cationic initiation conditions, but only low molecular weight homopolymers were obtained. Copolymerization of IF with styrene and with p-methoxy-α-methylstyrene also gave only low molecular weight products. The formation of only low molecular weight polymers in all polymerization reactions is believed to result from the effect of the unusually high stability of ferrocenyl carbenium ions on its propagation reaction. The observed polymerization behavior of α-trifluoromethylvinylferrocene is in accord with this conclusion. IDM and DIS did not form polymeric products under cationic conditions, although copolymers could be obtained for each of these monomers and styrene with a free radical polymerization initiator (AIBN).
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  • 36
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1749-1757 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Graft copolymerization of acrylonitrile (AN) onto isotactic polypropylene (PP) fiber has been studied by using gamma rays from a 2100 Ci 60Co source as initiator by preirradiation technique. The preirradiated PP was treated with AN and the mixture was graft copolymerized by heating to 100°C for different time periods. The percentage of grafting is determined as a function of total dose, reaction time, and monomer concentration. The effect of different solvents such as H2O, CH3OH, and dioxane upon percentage of grafting has been studied. The maximum effect was observed in water and the minimum in CH3OH. PP - g - PAN was characterized by IR spectroscopic and thermogravimetric methods. A plausible mechanism of gamma radiation induced grafting of AN onto PP in the absence and in the presence of solvents has been proposed. An attempt has been made to compare the relative abilities of different solvents to influence grafting.
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  • 37
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1759-1769 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A general synthetic method and characterization of bis(ether anhydride)s, the ether containing aromatic dianhydrides of the following structure, are presented. The method involves aromatic nitro-displacement of N-substituted 3- or 4-nitrophthalimide with bisphenoxides to form N-substituted arylene-bis(phthalimido)ethers or bis(ether imide)s. Sixteen structurally different bis(ether imide)s have been prepared and subsequently converted to the corresponding bis(ether anhydride)s. Bis(ether anhydride)s are stable crystalline compounds of a moderate reactivity. Unlike highly reactive dianydrides such as pyromellitic and benzophenonetetracarboxylic dianhydrides bis(ether anhydride)s are semipermanently stable against hydrolysis in the presence of atmospheric moisture.
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  • 38
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1797-1803 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New soluble aromatic polyamides with inherent viscosities of 1.0-1.7 dL/g were prepared by the low temperature solution polycondensation of 2,5-bis(4-aminophenyl) - 3,4-diphenylthiophene, bis(4-aminophenyl) ether, and aromatic diacid chlorides in N,N-dimethylacetamide. The polyamides and copolyamides are generally soluble in amide-type solvents. They have glass transition temperatures in the range of 280-325°C and showed no weight loss below 390°C on thermogravimetry curves in both air and nitrogen atmospheres.
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  • 39
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1267-1281 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The macromolecular chain conformational state during the amination of chloromethylated polystyrene (CMPS) with two aliphatic amines, namely methyl(2-hydroxyethyl)amine (MHEA) and N,N-dimethyl(2-hydroxypropyl)amine (DM2HPA), has been studied. Viscosimetric and light scattering measurements were performed during reactions in binary solvent mixtures. The observed kinetic deviations have been related with the conformational transformations of the macromolecular chain.
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  • 40
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2165-2175 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Dihydronicotinamide, anchored to a macroreticular polystyrene resin, reduces pyridine-2-carbaldehyde (PCA) in the presence of Mg2+ ions in acetonitrile. The reactions are clean at room temperature, the high rate precluding complications arising from slow side reactions. The influence of Mg2+ concentration on the rate of reduction of PCA by polymer-bound reagent and BNAH (1-benzyl-1,4-dihydronicotinamide; low-molar-mass analog) has been studied. Analysis of the kinetic data showed that of the processes contributing to the overall reduction, the reaction between the reductant and the complexed substrate proceeded at the highest rate. In the polymer-bound reagent, “site isolation” on the rigid matrix was observed to prevent bimolecular disproportionation of the neighboring dihydronicotinamides. Regeneration of the polymeric reagent was achieved with an efficiency of 98% per cycle.
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  • 41
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2177-2195 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyamides were synthesized at -60°, -40°, -20°, and 0°C from sebacyl bisketene and 1,6-hexamethylenediamine in either acetone or methylene chloride. At the lower reaction temperatures oligomers predominated in solution but at 0°C the product was crosslinked. The polyamides were subjected to m-cresol extraction at elevated temperatures for up to 14 days. The m-cresol soluble and insoluble fractions were characterized by weight, infrared spectroscopy, dilute solution viscosity, and gel permeation chromatography. Infrared analysis of the soluble and insoluble portions showed the degree of branching of the polyamide, identified the branching point at the secondary amide proton position, and gave an indication of the degree of branching required before insoluble products resulted. Dilute solution viscosity and gel permeation chromatography were used to demonstrate the existence of low molecular weight (Mw) oligomer species in the soluble portion. Differential scanning calorimetry experiments revealed that polyamides synthesized below their glass transition temperature would not crystallize which resulted in abnormal thermal characteristics. Annealing at elevated temperatures allowed crystallization to occur and the expected thermal character to develop.
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  • 42
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2247-2254 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The terpolymerization composition equation has been modified to eliminate the consideration of interactions between monomers 2 and 3 when they are present in low concentration in the feed mixture relative to monomer 1. Terpolymers with a wide variety of comonomers and compositions have been synthesized and used to demonstrate that a simplified terpolymerization equation accurately predicts terpolymer composition.
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  • 43
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2341-2359 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Esters of cyanoacetic acid are a novel class of epoxy curing agents. The model reaction between ethyl cyanoacetate (ECA) and phenyl glycidylether (PGE) yielded a cyano-spiro-dilactone under conditions similar to the resin cure. The structure of the spiro compound resulting from 2 ECA and 2 PGE was elucidated by MS, IR, 1H-, and 13C-NMR techniques. Ammonia is split off from 1 ECA and acts in statu nascendi as a satellite hardener. An overall model reaction equation for the cyanoacetyl cure is proposed. The cure of bisphenol A-diglycidylether (BADGE) with ECA and with neopentylglycol-biscyanoacetate (NPGCA) is described over a wide range of the molar ratio. Clear and tough solids are obtained with a glass transition temperature up to 130°C. Cyanoacetates are latent hardeners requiring a curing initiator. Since N-4-chlorophenyl N′-dimethylurea is a latent initiator, liquid “one-shot” systems can be formulated that are stable at room temperature and harden quickly above 120°C. Heat aging properties of cured specimens are reported. A series of novel liquid, resinous, and crystalline cyanoacetates and their potential as curing agents are described.
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  • 44
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2413-2423 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Copolymers of vinyl viologens such as N-vinylbenzyl-N′-yalkyl and N-(γ-methyacryloyloxy)propyl-N′-propyl-4,4′-bipyridinium dihalides and polar aprotic comonomers such as N-vinyl-2-pyrrolidone (VP) and N,N-dimethylacrylamide (DMA) were prepared by the copolymerizations of vinyl viologens with DMA and the chemical modifications of VP copolymers containing reactive halogens. Copolymers containing various viologen anions such as Br-, BF-4, SO42-, and I- were also prepared by the anion exchange of copolymers containing Cl-. The photocolor developments of these aprotic copolymers in the film state were completely reversible and faster than for the corresponding copolymers with protic comonomers such as acrylamide and 2-hydroxyethyl acrylate, all with characteristic absorption spectra attributable to single radical cations.
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  • 45
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2405-2411 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal polymerization of methyl methacrylate [MMA] was carried out using ylide (4-picolinium 4-chloro phenacyl methylide) as an initiator. The rate of polymerization (Rp) increases with increasing monomer and initiator concentrations; The exponent value has been computed to be 1 ± 0.02 and 0.5, respectively. The reaction was carried out at four different temperatures and the overall activation energy has been computed to be 16.01 kcal/mol. The polymerization was inhibited in the presence of hydroquinone as a radical scavanger. Kinetic studies indicates that the overall polymerization takes place by a radical mechanism.
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  • 46
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2481-2485 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Biacetyl is solvated by methanol or water giving an α-substituted alkanone. Irradiation of the solvated species at 300 nm in the presence of vinyl acetate or vinyl pyrrolidone, produces a significant amount of polymer. The photoprocesses leading to active free radicals are considered to be a type I photocleavage of the α-substituted alkanone.
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  • 47
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2487-2494 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Some polymers containing the nitroxyl radical structure were prepared and applied to the electron transfer agents from Fe(III) to benzyl alcohol. Benzyl alcohol was also oxidized by Fe(III) in two-phase or tri-phase systems using hydrophobic or hydrophilic polymers, which contain 2,2,6,6-tetramethylpiperidine-1-oxyl moiety, as an electron transfer catalyst. Especially, the hydrophilic polymers accelerated the oxidation of benzyl alcohol.
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  • 48
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2507-2526 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Representative polyethyleneimine-based polymers have been studied by 13C- and 15N-nuclear magnetic resonance spectroscopy and an extensive set of chemical shift assignments has been proposed for the complex spectra obtained. The samples in question represent a complex mixture of both protonated and nonprotonated primary, secondary, and tertiary as well as quaternary monomeric units.
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  • 49
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2495-2505 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In the photocrosslinking of poly(2,3-epithiopropyl methacrylate) (PETMA) films the effect of the pendant episulfide group's oxidation on the crosslinking of PETMA was investigated. Thermal crosslinking of PETMA is promoted by peroxides such as benzoyl peroxide and hydrogen peroxide. IR spectrum of the crosslinked PETMA showed that the reaction proceeded through the oxidation of episulfide groups by the peroxides. The anthracene (An) sensitized photocrosslinking of PETMA films also proceeded via the oxidation of episulfide groups by singlet oxygen. It was found that residual tetrahydrofuran (THF) in the films remarkably increased the rate of the photocrosslinking and/or reduced the induction period. From the further investigation concerning casting solvents it was found that residual CS2, CCl4, and CHCl3 in films increased the rate of the photocrosslinking and/or reduced the induction period of the photocrosslinking. The disappearance rate of An in the films was also increased by the presence of residual CS2, CCl4, and CHCl3, differring from the result of THF. These results were explained by a difference in lifetime of singlet oxygen in the films. From the results were explained by a difference in lifetime of singlet oxygen in the films. From the results concerning the effects of hydroperoxides such as THF hydroperoxide and t-butyl hydroperoxide on the photocrosslinking of PETMA films the acceleration effect of the residual THF was deduced to be due to the promotion of singlet oxygen-oxidation of sulfide groups by protic compounds such as THF hydroperoxide and H2O in the THF.
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  • 50
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2561-2565 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 51
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2589-2599 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of branched-chain methylsiloxane polymers built up of four-membered siloxane cycles and linear segments of zero to four siloxy units, and another series consisting only of siloxane cycles of five to eight members were investigated. The samples were pyrolyzed at temperatures increased stepwise from 300 to 800°C. The pyrolysate was analyzed online by gas chromatography and mass spectrometry. In the pyrolysates, series of cyclic, bicyclic, and polycyclic methylsiloxane compounds were found. Quantitative analysis of the pyrolysates shows that their composition reflects the composition and structure of the pyrolyzed polymethylsiloxane. The amount of the cyclic dimethylsiloxanes is related to the length of the linear siloxane segments between the branching points. The amount of bicyclic and polycyclic dimethylsiloxane oligomers in the pyrolysates is related to the average frequency and vicinity of the branching points.
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  • 52
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2601-2613 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyacetylene films have been rendered hydrophilic by treatment with aqueous KMnO4. The treated films were characterized by contact angle measurement, infrared spectroscopy, and x-ray photoelectron spectroscopy. We found that it is possible to lower the contact angle of H2O on polyacetylene from 72° to ca. 10° without significantly affecting the electrical conductivity afforded after I2 doping compared with similar doping of untreated films. The treated, hydrophilic films were found to be more permeable to aqueous ionic solutions than pristine polyacetylene.
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  • 53
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2659-2668 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(bismethylene hydroquinone) (PBHQ) has been synthesized. Fourier transform infrared, 13C solid-state CP/MAS NMR and elemental analysis provide strong evidence of two methylene bridges per hydroquinone molecule. The polymer was (1) air oxidized using ammonia and (2) chemically oxidized using bromine/KOH. The initial structure and oxidation process was studied by comparison of the unoxidized and oxidized polymers using Fourier transform infrared, elemental analysis, and 13C solid-state CP/MAS NMR.
    Additional Material: 6 Ill.
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  • 54
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2647-2657 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Kinetics of polymerization of acrylamide initiated by Thallium(III) perchlorate was investigated in aqueous perchloric acid medium in the temperature range of 55-70°C. The rates of polymerization were measured varying the concentration of the monomer, initiator, and perchloric acid. The rate of polymerization was found to increase with increase of temperature, monomer concentration, initiator concentration, and perchloric acid concentration. The effect of additives like different solvents, surfactants, and retarders on the rate of polymerization was studied. Molecular weights of the polymer were determined by viscometry. The chain transfer constants for the monomer (CM) and that for the solvent dioxan (Cs) were calculated to be 7.33 × 10-3 and 6.66 × 10-3, respectively. From the Arrhenius plot, the overall activation energy (Ea) was calculated to be 10.68 kcal/mol. The energy of initiation was calculated to be 12.36 kcal/mol. Depending on the results obtained, a suitable reaction mechanism has been suggested and a rate equation has been derived.
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  • 55
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2669-2678 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of para-linked phenylene, bis(trifluoromethyl)biphenylene and stilbene copolyamides was synthesized in order to examine the effect of comonomer ratio on absorption spectra, solubility and birefringence. The data clearly showed that decreasing the stilbene content significantly lowered the birefringence and hypsochromically shifted the absorption band. A decrease in the biphenylene content broadened and bathochromically shifted the absorption band and lowered the birefringence and the solubility.
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  • 56
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2683-2707 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The complex degradation behavior of a poly(vinyl chloride) (PVC) cable jacketing material in combined radiation/temperature/air aging environments is experimentally separated into two dominant radiation dose-rate effect mechanisms. The first, operative at high dose rates, involves diffusion-limited oxidation, which leads to heterogeneously oxidized samples. The second, important at low dose rates, involves thermally-induced breakdown of intermediate peroxides. In the homogeneous degradation regime, a theoretical kinetic model is derived which, based on experimental evidence, assumes unimolecular termination kinetics and rate-determining, hydroperoxide-mediated branching reactions. Dependent upon the ratio of particular rate constants, the model predicts that dose-rate effects will either continue to increase or eventually disappear as the dose rate is lowered. Theoretical analysis of sequential (radiation followed by temperature exposures) aging experiments allows a time-temperature-dose rate shifting procedure to be developed. Using this procedure, higher temperature combined environment results can be shifted to a lower reference temperature, thereby extending the lower temperature results to lower (and experimentally inaccessible) dose rates. By applying this procedure to experimental PVC data, evidence in support of the theoretical model is obtained. In addition, model predictions are shown to agree with 12-year real-time aging results.
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  • 57
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2739-2746 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The gamma-ray induced solid-state polymerization of binary mixtures consisting of a maleimide derivative as the first component and acenaphthylene or trans-stilbene as the second component was investigated regarding the occurrence of copolymerization. The binary solid mixture of these compounds exhibited a phase-equilibrium diagram including a simple eutectic mixture, and the irradiation caused the formation of a random copolymer together with that of homopolymers of component comonomers. The reaction rates and the composition of products suggested that the mobility of monomer molecules in the crystals affected the solid-state polymerization significantly. The solid-state copolymerization was supposed to take place by the diffusion of comonomer molecules via a vapor phase to the nuclei where the copolymerization proceeded.
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  • 58
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2727-2738 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: As model compounds for determining the potential adaptability of novel leaving group to polyamide synthesis, 2-aryl-5-benzoylthio-1,3,4-oxadiazoles having various electron accepting and donating groups in the oxadiazole unit were successfully prepared from the benzoylation of the corresponding 2-aryl-1,3,4-oxadiazoline-5-thiones under kinetically controlled conditions ( 〈 -50°C). The aminolyses of all the benzoyl thioesters by aniline afforded quantitative yields of benzanilide at room temperature in a short reaction time. Polycondensations of new active dithioesters, 5,5′-isophthaloyldithiobis-2-aryl-1,3,4-oxadiazoles, with both aliphatic and aromatic diamines occured quite rapidly even at room temperature to form polyamides with reduced viscosities up to 0.41 dL/g. The reactivities of the dithioesters having electron accepting groups such as p-chloro and p-nitro groups, particularly p-nitro groups, toward diamines were much higher than that of the dithioester having no such groups, but the introduction of electron donating p-methyl group had an adverse effect. The effects of reaction conditions such as solvent, temperature, and monomer concentration on the reduced viscosity of polyamides were also investigated. It was found that monomer concentration had a remarkable influence on the molecular weight of the resulting polyamides.
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  • 59
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2767-2778 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of a polymerizable methacrylate bearing the dibenzo-18-crown-6 moiety (5) was effected in three steps by condensation of 3,4-dihydroxybenzaldehyde with 1,2-bis[2′-(2″-chloroethoxy)ethoxy]benzene (2), reduction of the resulting 4-formyldibenzo-18-crown-6 (3) to 4 and subsequent reaction of 4 with methacryloyl chloride. The methacrylate (5) was polymerized in solution using 2,2′-azobis(isobutyronitrile) (AIBN) as the initiator and gave a solid polymer (6) having a midrange Tg of 67°C. The polymethacrylate bearing pendant crown-ether structure (6) was found to effectively complex potassium ions and was clearly more effective in its complexing ability than dibenzo-18-crown-6 (7) or a polyurethane bearing the dibenzo-18-crown-6 moiety (8) in the polymer backbone. The subject polymer (6) was also found to complex and consequently solubilize several metal 7,7,8,8-tetracyanoquinodimethane (TCNQ) salts to give semiconducting compositions. Evidence is given that in the presence of the neutral acceptor molecule, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), the polymethacrylate (6) acting as a donor, gives rise to a charge-transfer (C/T) complex.
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  • 60
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2819-2832 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The stability against electrolytes for all-sulfate, all-carboxyl, and all-hydroxyl, polystyrene model latexes followed the order, sulfate 〉 carboxyl 〉 hydroxyl when determined from an IR light scattering technique. Two types of hydroxyl endgroups were identified by 13C-NMR (chemical shift correlations, and model compound comparisons), for the polystyrene model latexes. One type was due to termination of growing chain with an oligomer with a single monomer unit, and the other due to termination of growing chains. The surface hydroxyl groups of an all-hydroxyl latex were derivatized with hexafluoroacetone, and quantified using 19F-NMR techniques. Good agreement with the indirect conductometric titration values were obtained.
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  • 61
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2841-2850 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: To develop a polymer membrane whose permeability of water-soluble compounds could be controlled in response to a pH change of the medium, a polyelectrolyte membrane containing an aromatic carboxyl group, i.e., 4-carboxyacrylanilide (CAAn)-methyl methacrylate(MMA) copolymer membrane, was prepared. The water content of the CAAn-MMA copolymer membrane increased with increasing pH owing to ionization change in the CAAn moiety. This increase was particularly remarkable in the pH range from 5 to 7. The change in water content was reversible and could be controlled by the CAAn composition in the copolymer. Permeation of 1,4-bis(2-hydroxyethoxy)benzene(DHEB) through the CAAn-MMA copolymer membrane was investigated in solutions of various pH. Change in the permeability of DHEB in function of the pH was similar to the change in membrane water content. This was explained by an increase in the permeation pathway of DHEB in the membrane, in proportion to that in the water content. Moreover, when a pH-sensitive membrane was placed in a solution in which an enzymatic reaction occurred, substrate-induced permeation control of DHEB through the CAAn-MMA copolymer membrane was possible.
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  • 62
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2857-2863 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Carbon 1s (C1s) core-level positions have been calculated for two model compounds which are similar in structure to the PMDA part of the PMDA-ODA monomer of polyimide. It is found that either one or two N-phenyl imide groups fused to a benzene ring will lower the C1s energy levels of the benzene ring. The difference in previous interpretation of the origin of the C1s (ESCA) spectra between the two model compounds examined is shown to be consistent with the difference in calculated magnitude of this shift between the two compounds.
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  • 63
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1847-1849 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Tab.
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  • 64
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1853-1859 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Perfluoro-2-alkynenitriles can be polymerized into soluble polymers at low temperatures by π-bis(benzene)chromium(O) in benzene/pyridine (10:1) solution. The degree of polymerization is 7.4 for perfluoro-2-butynenitrile, 6.5 for perfluoro-2-pentynenitrile, and 11 for perfluoro-2-hexynenitrile. These polymers were examined by UV and IR spectra. Their thermal stability and the electrical conductivity of nondoped polymers were also studied. The conductivities of polyperfluoro-2-butynenitrile(PPFBN) and polyperfluoro-2-pentynenitrile are found to be 4.8 × 10-8 and 6.6 × 10-8Ω-1 cm-1, respectively.
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  • 65
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1885-1891 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 5 Ill.
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  • 66
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1893-1906 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reactions of poly(epichlorohydrin) (PECH) and poly(2-chloroethyl vinyl ether) (PCEVE) with various reagents were investigated using phase transfer catalyst (PTC) such as tetra-n-butylammonium bromide (TBAB), 18-crown-6 (CR6), and dicyclohexyl-18-crown-6 (DCHC) is a solid - liquid two-phase system. Although the reactions of these polymers hardly occurred without PTC in nonpolar solvents such as toluene and diglyme under mild conditions, the addition of PTC caused the reactions to proceed smoothly under the same conditions. In addition, the reactions of PECH and PCEVE with a strong base such as potassium hydroxide proceeded selectively through β-elimination reaction to produce the polymers with pendant vinyl groups. These results suggested this method is useful for the syntheses of functional polymers. On the other hand, it turned out that quaternary ammonium salts such as TBAB have higher catalytic activity than crown ethers such as CRG and DCHE in these reactions. Furthermore, the catalytic activity of quaternary ammonium salts was strongly influenced by their chain length and the structure of the polymers.
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  • 67
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 1907-1916 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: We report a study of the conditions of the phosphorylation reaction for the preparation of aromatic polyamides using the Higashi reaction medium. For poly(p-phenylene terephthalamide) (PPD-T), the optimum conditions are: reaction temperature, 115°C; monomer concentration, C = 0.083 mol/L; and ratio of triphenyl phosphite (TPP) to monomer, 2.0. These optimum conditions produce PPD-T having ηinh = 6.2 dL/g. At temperatures of 120°C and above PPD-T precipitates from the reaction mixture, leading to lower molecular weights. At lower temperatures the reaction mixture gels, and the gel time decreases with increasing reaction temperature. However, polycondensation continues in the gel state. Monomer concentrations C = 0.10 mol/L and above produce precipitation and yield polyamides of lower molecular weight. For the preparation of poly(p-benzamide) (PBA), the optimum ratio of TPP to monomer is 0.6 for either p- aminobenzoic acid or N-4-(4′-aminobenzamido)benzoic acid. In the former case the inherent viscosity of polymer prepared at 115°C showed little dependence upon the concentration of the monomer. The highest value, ηinh = 1.8 dL/g, was obtained with C = 0.40 mol/L and a TPP/monomer ratio of 0.6. However, for the same TPP/monomer ratio, the monomer containing a preformed amide linkage, N-4-(4′-aminobenzamido)benzoic acid, gave PBA with ηinh = 4.6 dL/g when the monomer concentration is 0.33 mol/L. This is the highest value reported for PBA using the phosphorylation reaction. In A-A + B-B polycondensation, examples in which one of the monomers contained one or two preformed amide linkages produced polyamides having ηinh = 7.8 and 8.9 dL/g, respectively.
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  • 68
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The preparation and radical-initiated polymerization of a carbazole-substituted N-acylated dehydroalanine, namely, 2-(9-carbazolyl)acetylaminopropenoic acid (7) and its methyl ester (6) is reported. The monomers 6 and 7 were prepared by dehydrochlorination of N-acylated β-chloroalanine derivatives. The monomer model compounds for the two polymers, namely, 2-(9-carbazolyl)acetylamino-2-methylpropanoic acid (11) and its methyl ester (10), were also prepared. The polymers and their monomer model compounds were characterized by elemental analysis, IR and 1H-NMR spectra. The polymers 12 and 13 of different molecular weights could be obtained by changing the monomer-to-initiator ratios used in polymerization experiments.
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  • 69
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2089-2098 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal and radical-induced polymerizations of 9-anthrylmethyl acrylate (I), 9-anthrylmethyl methacrylate (II), 1′-(9-anthryl)ethyl acrylate (III), and 1′-(9-anthryl)ethyl methacrylate (IV) have been studied. It was found that the radical-induced polymerization takes place for the methacrylates only, while thermal polymerization leads to polymers for both types of monomers and takes place by Diels-Alder cycloaddition in the case of acrylates, and by both normal enchainment and Diels-Alder cycloaddition in the case of methacrylates.
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  • 70
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2099-2107 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The first high molecular weight soluble, formable organogermane homopolymer (n-Bu2Ge)n was synthesized by the sodium coupling of n-Bu2GeCl2 in toluene. Soluble organogermane/organosilane copolymers [(X2Ge)x(YZSi)y]n were prepared by sodium coupling of X2GeCl2 and YZSiCl2 in different molar ratios (X = n-bu, Ph; Y = n-hexyl, cyclohexyl; Z = Me). Germanium-containing polymers and copolymers with organosilanes are highly absorbing between 300-360 nm, with the absorption maxima dependent on the nature of the substituent and the ratio of X2Ge:YZSi in the polymer. These polymers are photoactive and display bleaching behavior with photoscission.
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  • 71
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2255-2277 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermal effects accompanying vacuum deposition of poly(chloro-para-xylylene) in the temperature range between -196 and 0°C have been studied using two separate methods. One is based on the recording of the rate of evaporation of liquid nitrogen and it is used for the deposition at -196°C, and the second involves the recording of changes in the substrate temperature and is used for the deposition in the range of -162 to 0°C. These methods enable us to observe two distinct effects: fast (discrete), resulting in the appearance of sharp, exothermic spikes; and slow (continuous), resulting in the shift of the baseline. The shift of the baseline exhibits a well-defined maximum at about -65°C and this temperature is attributed to the melting point of the monomer. The fast process always occurs below this temperature and is explained as a solid state, chain addition polymerization. The quantification of the heat effect at -196°C strongly suggests that the quinonoid form of the monomer participates in the propagation step of this chain reaction. The fast (solid state) and the continuous modes of polymerization may occur simultaneously in the range of about -140 and -65°C. The frequency of the initiation which is the formation of dimer radical seems to control the occurrence of these two modes of polymerization.
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  • 72
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2283-2289 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The microstructure of tetrahydrofuran (A)-3,3 dimethyloxetane (B) copolymers was studied by 13C-{1H}-NMR spectroscopy. Only the methyl carbons corresponding to the 3,3 dimethyloxetane unit appear as a singlet, whereas the other carbons present a more complicated spectral pattern than it would be expected if ∊ effects were negligible. The assignment of the resonance signals allowed the determination of the values of the probabilities of the different triads, which were in good agreement with those obtained from the reactivity ratios.
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  • 73
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2319-2326 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 4 Ill.
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  • 74
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2333-2340 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Pure isotactic and enriched syndiotactic poly(tributyltin methacrylate) were synthesized by the reaction of the respective poly(methacrylic acid) with tributyltin oxide. The heterotactic polymer was prepared in a similar manner and from free radical initiated (AIBN or BPO) polymerization of tributyltin methacrylate. In each case, polymer configuration was confirmed by 1H-NMR of the hydrolyzed/esterfied product. The relatively large 119Sn-NMR linewidth of the isotactic tributyltin containing polymer suggests an intra-molecular exchange of the pendant tin groups. Tg, Td, and Mv data are also reported. Poly(tributyltinmethacrylate-co-styrene) was prepared by free radical polymerization and reactivity ratios [r(styrene) = 0.51, r(TBTM) = 0.49] and Q-e values for TBTM (0.78, 0.38) were determined.
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  • 75
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2361-2376 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Photocrosslinkable polyesters of m- and p-phenylenebis(α-cyanoacrylic acids) (I-a and I-b), m- and p-phenylenebis(α-cyanobutadiene carboxylic acids) (I-d and I-e), p-phenylenebis(acrylic acid) (I-c), and p-phenylenebis(butadiene carboxylic acid) (I-f) were prepared, and their photosensitivities were investigated. The spectral sensitivities of I-a, I-c, I-d, and I-e ranged up to 365, 385, 510, and 560 nm, respectively. This order corresponds to that of λmax due to the π-π* transition in their absorption spectra. I-e was sensitive to the visible part of argon ion laser even in the absence of photosensitizer. The highest sensitivity observed with I-e was estimated to be 1.5 mJ/cm2. In contrast, the sensitivity of I-c was low (〉 105 mJ/cm2) and that of I′-d, a modified I-d, was 1300 mJ/cm2, respectively. Addition of 2,6-di(4′-methoxyphenyl)-4-(4′-n-amyloxyphenyl)thiapyrylium perchlorate to them extended their sensitivity range, improving their sensitivity values to 35 and 110 mJ/cm2, respectively.
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  • 76
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2385-2404 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In a previous paper, potassium 2-(cytos-1-yl)propanoate was grafted onto polyethylenimine of various molecular weights. These water-soluble polynucleotide analogs exhibited remarkable properties in their solution ultraviolet spectra. High hypochromicity values of 50% and 54% have been observed in alkaline aqueous solution and 50% trifluoroethanol solution, respectively. Percent hypochromicity value was observed to be directly proportional to percent graft. Red shift and hyperchromicity as a function of pH were observed for both the monomer model and the graft polymers. Light-scattering experiments on nucleic acid base grafted hydrophilic polymer backbones were carried out. Radius of gyration and second virial coefficient values indicated stiff macromolecules, rodlike in nature. Therapeutic potential of cytosyl grafted polyethylenimine was suggested by the results from continuous mixing experiments with polyinosinic acid and polyguanylic acid. Job plots showed enhanced hypochromicity, whose magnitude was dependent upon the polynucleotide and the base-base distance.
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  • 77
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2425-2439 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Glow-discharge plasma polymerization of hexamethylcyclotrisiloxane was carried out on the cellulose acetate substrate in the presence of iodine crystal and the effect of I2 doping on liquid permeability such as water, cyclohexane, alcohol homologues, and a water-alcohol mixture was investigated. It was found that I2-doped poly(siloxane) (PHMS-I2) membrane exhibited larger water permeability than nondoped (PHMS) membrane with anomalous pressure dependence (fourth power with pressure gradient). The permeability of alcohol homologues of PHMS membrane increased with increasing the molecular size and the hydrophobicity, whereas that of PHMS-I2 membrane decreased significantly. The presence of a small amount of hemoglobin also increased the water permeability of both membranes. From the results of flow tests of various kinds of fluid it was assumed that these membranes permeate the liquid predominantly by solution-diffusion mechanism.
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  • 78
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2441-2446 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyacetylene (PA) deposited on a platinum surface is synthesized by electrochemical polymerization of acetylene in a cell with platinum strip as cathode, nickel strip as anode, and nickel bromide in acetonitrile as electrolyte. The electrolytic solution is presaturated with acetylene. The PA so produced has a granular morphology and high surface area (79 m2/g), and is insoluble. Polymerization at lower temperature gives higher content in cis units. It has the same chemical structure as that produced using the Shirakawa method as examined by elemental analysis, infrared spectroscopy, x-ray diffraction, and differential scanning calorimetry.
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  • 79
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2447-2459 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Procedures for the synthesis of polyacetylene ([CH]x) with Mn (number average molecular weight) from 400 to about 106 have been developed. This probably represents the largest range of molecular weight (MW) obtainable for a given monomer by a single initiator system. The catalyst residue level in [CH]x can be significantly reduced by acidic-methanol purification. The very low MW polymer L-[CH]x (polyacetylenes with Mn 400-500), has the same cis crystal structure as the higher MW polymers but is less ordered along the c-axis. It is isomerized to the trans material with apparently a more compact unit cell than high MW polymers. There is annealing of crystallite which increases the longitudinal order during thermal isomerization. This process occurs more readily and with lower activation energy in L-[CH]x than for polymers with higher MW. Isomerization of high MW polymers tends to trap cis units which can result in degradation as evidenced by the formation of sp3 carbon vibrations in IR spectra. This is true even for L-[CH]x after prolonged heating. The results render credence to the proposal based on anamalous resonance Raman scattering profile that there can be very short trans segments in thermally isomerized trans-[CH]x.
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  • 80
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2461-2479 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This paper further investigates imide formation in amidation reactions involving Bischloride A2 and suitably selected mono- and difunctional analogues on the one hand, and primary aromatic mono- and diamines on the other. It also investigates the reaction of these acid chlorides with secondary mono- and diamines. If, say, N,N′ dimethyl p-phenylene diamine and hydroquinone dioxyacetyl chloride or bischloride A2 were to react quantitatively, then a linear unbranched polyamide would be expected to be the result which, in the absence of any hydrogen remaining at the amide link, would no longer present a site for further electrophilic attack on the part of the exceptionally reactive aroxyacetyl chloride. There also arises the possibility that a monoamine such as aniline could conceivably act as a difunctional reagent in the presence of aroxyacetyl chlorides. In the event of this reaction proceeding quantitatively one would expect to obtain a linear polyimide in which each imide-nitrogen atom carries a phenyl group. In carrying out the experimental preparative work which is required to elucidate these points we used both monofunctional reactants as model compounds and difunctional reactants in order to assess the polymeric resultants. The products were characterized by means of 1H-NMR, 13C-NMR, IR spectroscopy, TLC, and Tg determinations. The conclusions drawn on the basis of the experimental work provided a satisfactory interpretation of the complex reactions which occur during the polyamidation of bischloride A2. They also point to interesting possibilities for the use of difunctional aroxyacetyl chlorides as modifying comonomers in minor amounts in the preparation of copolyaramides with reduced crystallinity. Such copolyaramides would be expected to have better solubility in common solvents and to be more easily processable than the rather specialized and extremely high-melting polyaramides currently commercially available and could therefore extend the range of useful applications for this class of polymers.The experimental section is preceded by an introduction which briefly reviews the “state of the art,” especially as far as bischloride A2-based polyamidation reactions are concerned. It is followed by a discussion of the results, by the conclusions, and a brief summary.
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  • 81
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2527-2537 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymerization of three tert-alkylacetylenes (3,3-dimethyl-1-pentyne, 3,3-dimethyl-1-nonyne, 1-adamantylacetylene) by Mo- and W-based catalysts provided new polymers in virtually quantitative yields. In contrast, Ziegler catalysts did not polymerize these monomers. Every polymer had a form of white solid, and had alternating double bonds along the main chain. Though some of poly(3,3-dimethyl-1-pentyne)s contained a toluene-insoluble fraction, the polymer was totally soluble when proper polymerization conditions were chosen. The molecular weights of soluble fractions were as high as 3 × 105. Poly(3,3-dimethyl-1-nonyne) was also partly insoluble in toluene, and the quantity of soluble fraction was less than that of poly(3,3-dimethyl-1-pentyne). The geometric structure of these two polymers could be controlled by the choice of suitable polymerization conditions. Poly(1-adamantylacetylene) was insoluble in any organic solvents. Copolymerization of 1-adamantylacetylene with suitable comonomers afforded soluble copolymers.
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  • 82
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2557-2559 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 83
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2539-2555 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The pyrolysis of polymethyl acrylate is reported with identification of the major pyrolysis products. The mechanism involving random homolytic scission of the chain followed by a series of intermolecular and intramolecular transfer reactions as proposed by Cameron and Kane and extended by Haken, Ho, and Houghton is further developed. Reaction mechanisms are postulated for all of the products produced and ion fragmentation mechanisms for the various spectra produced are shown. The paper also forms the basis for a study of the homologous alkyl polyacrylates, both straight and branched chain esters being considered these having not been previously extensively studied.
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  • 84
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2579-2587 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: By coupling the evolved gas detection method with various analysis methods, the thermal decomposition products of the statistical vinyl alcohol/vinyl acetate copolymers were analysed.The data are presented comparatively with those obtained for the corresponding block copolymers of the same composition.The differences in the nature and amounts of the reaction products are explained by the structural characteristics of the copolymers.
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  • 85
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2567-2578 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of N-vinylcarbazole has been carried out at 60°C under nitrogen with different grades of carbon black, N220, N110, N330, and N660 as heterogeneous catalysts. The order of efficiency of the catalysts in regard to the polymerization is: N220 〉 N110 〉 N660 〉 N330. Effect of solvent polarity on the polymerization has been studied with acetonitrile, 1,2-dichloroethane, and toluene-nitrobenzene mixtures. Nitrobenzene, with highest polarity, affords the highest rate, which decreases with decreasing nitrobenzene percentage in the solvent mixture. These features suggest the polymerization to be cationic in nature. The relative viscosities of the polymers are low, but tend to increase only slightly with increasing nitrobenzene content. The rate of polymerization can be expressed by the relation \documentclass{article}\pagestyle{empty}\begin{document}$$ - \frac{{{\rm d}\left[ {\rm M} \right]}}{{{\rm dt}}} = k_1 [{\rm M}]{\rm [Carbon Black]} $$\end{document} A suitable kinetic model has been presented in conformity with the experimental findings.
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  • 86
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2631-2646 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Kinetics of polymerization of N-vinylcarbazole over Co(II)-13X molecular sieves in toluene have been studied. The rate of polymerization (Rp) has been found to be second order with respect to percent exchange level of Co(II) and also to the NVC concentration at all the reaction temperatures of 40, 50 and 60°C. The rate increases with decreasing pH of the original exchanging salt solution up to a pH of about 3.5, beyond which it falls. The overall activation energy of polymerization has been found to decrease with increase in monomer concentration, exchange level of Co(II), and the hydrogen ion concentration of the original exchange solution. Average degree of polymerization also follows a similar trend. A mechanism of polymerization involving simultaneous propagation on both metal ion Co(II) and proton on a zeolite surface has been suggested. The two propagation routes are characterized by an average activation energy of 10.36 kcal/mol and 5.40 kcal/mol on the metal ion and proton centers, respectively.
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  • 87
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2615-2630 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The emulsifier-free emulsion polymerizations of styrene in the presence of the surface active comonomer, undecylenic isethionate sodium salt (at concentration below its critical micelle concentration), and of the initiator, potassium persulfate, indicate that the number of polymer particles and the rate of polymerization at steady state is dependent on 1-power of the comonomer concentration and 1/2-power of the initiator concentration. This result suggests a homogeneous nucleation mechanism by which particles are formed from coiled-up oligomeric radical chains originally dissolved in the aqueous phase. Size distribution of the particles is rather narrow and has a uniformity very close to one (ca. 1.02) after 30% conversion. Addition of salt such as sodium sulfate to increase the ionic strength in the aqueous phase results in a formation of micelles (which can grow to become polymer particles) in addition to the formation of polymer particles through the homogeneous nucleation mechanism. Variation of the ionic strength leads to a variation in the number of polymer particles due to a competition between these two nucleation mechanisms and gives a minimum of the number of polymer particles and a maximum of the average particle diameter.
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  • 88
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2757-2765 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyamides were synthesized from 2,5-dimethoxyterephthaloyl dichloride and diamines. Also, polyimines and polyaldoles were prepared from 2,5-dimethoxy-terephthaldehyde with diamines and ketones. The polymers were characterized by elemental analysis and infrared and NMR spectroscopy. Their intrinsic viscosity, glass transition temperature, and thermaldecomposition temperatures were determined.
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  • 89
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2747-2756 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The influence of the acyl groups of N-acylated hindered amine on the photostabilization of polymers was discussed. The effects of the N-acyl derivatives of 4-benzoyloxy-2,2,6,6-tetramethylpiperidine (6) in the photostabilization of polypropylene were compared. Although the stabilizing effects of all the N-acyl derivatives were lower than that of the N-oxyl derivative (7), N-acryloyl (4) and N-benzoyl (5) derivatives showed higher effects than that of parent N—H 6. To discuss the stabilizing mechanism of N-acylated hindered amine, the reaction of N-acylated hindered amine with model hydroperoxide (tert-butyl hydroperoxide) was carried out at an elevated temperature (132°C). N-Acylated hindered amine decomposed tert-butyl hydroperoxide more rapidly than corresponding secondary hindered amine, and changed into the parent secondary amine.
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  • 90
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2779-2790 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: High-molecular-weight, film-forming, amorphous polyamides have been prepared from 2,6(7)-diamino-9,10-dihydro-9,10-ethanoantracene with adipic, sebacic, dodecanoic, isophthalic, 4,4′-oxybibenzoic, 2,6-naphthoic, 4,4′-bibenzoic, and terephthalic acid. Thermal elimination of ethylene from these polymers has yielded the corresponding polyamides from 2,6(7)-diaminoanthracene which were of high molecular weight, film forming, and crystalline.
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  • 91
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2791-2802 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: High molecular weight, film-forming, amorphous polyesters have been prepared from 2,6-dilydroxy-9,10-dihydro-9,10-ethanoanthracene with adipic, sebacic, dodecanoic, isophthalic, 4,4′-oxybibenzoic, 2,6-naphthoic, 4,4′-bibenzoic, and terephthalic acid. Thermal elimination of ethylene from these polymers has yielded the corresponding polyesters from 2,6-dihydroxyanthracene which were of high molecular weight, film forming, and crystalline.
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  • 92
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2803-2818 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(amino-p-benzoquinone)amides were indirectly prepared by low-temperature polycondensation of 2,3,5,6-tetraamino-p-hydroquinone, with terephthaloyl, isophthaloyl, or phthaloyl dichloride and subsequent oxidation of the obtained poly(amino-p-hydroquinone)amides. Then the poly(amino-p-benzoquinone)amides were converted by cyclodehydration with heating to the corresponding poly(p-benzoquinono)diimidazoles. The prepared redox thermally stable polymers were characterized by elemental analysis, UV, and IR spectral study, inherent viscosity solubility, and thermal analysis (DSC, TGA). The synthesis and properties of the corresponding model compounds are also reported.
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  • 93
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2833-2839 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A number of simple natural rubber (NR) and polybutadiene (BR) formulations were vulcanized in a differential scanning calorimeter. From the shapes of the exothermal cure curves the interaction of curatives can be examined. It is suggested that polysulphidic-accelerator-terminated pendent groups could either crosslink, or be chelated with zinc ions. The latter reaction allows interaction with accelerator molecules to reform the unchelated pendent group, and a zinc accelerator complex, that, in turn, can react with sulphur and rubber molecules to give pendent groups. Differences in the behavior of NR and BR are attributed to the relative rates of these two reactions in the elastomers. Bis(2-benzothiazolyl) disulphide does not react with zinc, and it is suggested that it coordinates with the zinc dithiolate accelerator complex, increasing its activity.
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  • 94
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction promoted by Vilsmeier adduct derived from tosyl chloride (TsCl) with N,N-dimethylformamide (DMF) was successfully applied to the preparation of copolyesteramides of high molecular weights directly from aromatic dicarboxylic acids, diamines, and bisphenols. The polycondensation was significantly affected by the reaction of activated dicarboxylic acids with bisphenols and diamines. Addition of a mixture of bisphenols and diamines likely caused gelation of the reaction mixtures, resulting in insoluble polymers, especially with high mol % diamines. Stepweise addition of them, however, gave the homogeneous reaction mixtures and copolymers of better solubility. These phenomena were studied in terms of sequence length distribution of polyester units, which was estimated by thermal analyses of the random copolymers prepared under various conditions for the initial reaction with bisphenols.
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  • 95
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2865-2874 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Gelatin a derived protein from collagen can be modified at 60°C by allowing it to react with ethyl acrylate by use of a novel initiator technique. The polymeric ethyl acrylate side chain is chemically bonded to gelatin. The effects of synthetic variable in the graft copolymerization reactions have been discussed in the light of percent grafting, grafting efficiency, and the rate of polymerization.
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  • 96
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2875-2878 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
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  • 97
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2897-2911 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The complex resins derived from furfuryl-alcohol polymerization are a result of at least four competing reactions. By converting the alcohol to its acetate ester, however, three of these reactions can be eliminated. The simpler polymer derived from furfuryl acetate has been characterized spectroscopically, and an interesting chromophoric side reaction of the polymerization has been identified. The remarkable ability of the polymer to crosslink at room temperature upon precipitation from solution is also of interest.
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  • 98
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2931-2945 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thin films of cured MY720/DDS epoxy resins were treated with blocking reagents for hydroxyl, amine, and epoxide functional groups. Infrared spectroscopy (IR) and differential scanning calorimetry (DSC) were used to monitor the progress of the reaction. Treated films were soaked in distilled water at 30°C for 720 h, and the corresponding moisture absorption determined gravimetrically. Samples treated with N-methyl-N-t-butyldimethylsilyl trifluroacetamide (MTBSTFA) containing 1% t-butyldimethylchlorosilane (TBDMCS) in dimethylsulfoxide (DMSO) at 30°C showed a maximum reduction in the IR peak at 3400 cm-1 (OH and NH) of 39% and a 100% reduction in the epoxide peak at 904 cm, -1. The moisture absorption was 1.9%, a reduction of 58% compared to the untreated films (ca. 4.5%). The reactions show dependencies on time and temperature and are diffusion controlled. Samples treated with trimethylsilyl isocyanate (TMSI) in DMSO a 70°C showed 72% reduction in the 3400 cm-1 IR peak; DSC thermograms do not show an exothermic energy, suggesting that all epoxide groups reacted. These reactions are primarily dependent on time and temperature. The moisture absorption of TMSI treated samples was 1.0% (75% reduction). Samples were also treated with m-trifluoromethyl phenyliscyanate (MTFPI). The reduction in the IR peak at 3400 cm-1 was 9%, but the moisture absorption was 2.4% - a reduction of 47%.
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  • 99
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 2973-2987 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymerization of styrene miniemulsions, prepared using a mixed emulsifier system comprising sodium lauryl sulfate and cetyl alcohol, was carried out using both water-soluble (potassium persulfate) and oil-soluble [2,2′-azobis-(2-methyl butyronitrile)] initiators. The effects of variation of initiator concentration, polymerization temperature, and added inhibitor on the kinetics and particle-size distributions were investigated to obtain more quantitative evidence concerning the locus of polymerization in miniemulsion systems. Experimental results for the kinetics and particle-size distributions clearly showed that monomer droplets became the main source of polymer particle formation. This was attributed to the fact that stable emulsions with droplet diameters in the range of 0.05 to 0.15 μm were produced using this mixed-emulsifier system. In this size range, droplet initiation could effectively compete with other mechanisms due to their large surface area. Their size was indeed similar to the corresponding latex particle size obtained after polymerization.
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  • 100
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    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 265-277 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Some ω-(1-imidazolyl) and ω-[4(5)-imidazolyl]alkanoic acids were synthesized and grafted onto poly(vinylamine) with an amide bond. These water-soluble grafts were used to study the kinetics of the esterolysis of activated phenyl esters. The 1-substituted imidazoles were prepared by the reaction of the sodium salt of imidazole with the ethyl ω-bromoalkanoates. The 4(5)-substituted imidazoles were prepared from urocanic acid or 4(5)-hydroxymethylimidazole. The ω-(1-imidazolyl)alkanoic acids were grafted onto poly(vinylamine) via their acyl-guanidine derivatives; the 3-[4(5)-imidazolyl]propanoic acid was grafted with a water-soluble carbodiimide.
    Type of Medium: Electronic Resource
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