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• 1980-1984  (2,658)
• Physics  (2,657)
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• 1
Electronic Resource
New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2287-2291
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
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• 2
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2265-2273
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: By interfacial polycondensation of 4,4′-dimercaptobenzophenone with oxalyl, succinyl, adipolyl, suberoyl, and sebacoyl chlorides new polythioesters were obtained. To determine the optimal conditions of interfacial polycondensation the influence of the following factors on yield and value of reduced viscosity was studied: type of organic phase, the quantitative ratio of aqueous to organic phase, concentration of hydrogen chloride acceptor, molar ratio of reagents, temperature of reaction, rate of acid chloride addition, and contribution of catalyst. A thorough examination of the polycondensation of dithiol with adipolyl and sebacoyl chlorides was carried out. The structure of all polythioesters obtained under model conditions was determined by elemental analysis and infrared spectra. Initial decomposition and intensive decomposition temperature were defined by the curves of thermogravimetric analysis. Mechanical and electrical properties of the polythioesters obtained from 4,4′-dimercaptobenzophenone and adipoyl and sebacoyl chlorides were determined. The molecular weight was not measured because of the low solubility of the polythioesters.
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• 3
Electronic Resource
New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3407-3415
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The small-angle X-ray scattering method was applied to evaluate macromolecular parameters of Agave fibers (Agave sisalana, A. cantala, A. hybrid, A. elongata, and A. ameniensis). The macromolecular parameters such as specific inner surface, percentage of void, length of coherence, range of inhomogeneity, and transversal lengths were evaluated. The correlation of macromolecular parameters with the average breaking strength of Agave fibers did not lead to a linear relation, however, the specific macromolecular organization in A. sisalana manifested higher breaking strength.
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• 4
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3439-3446
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Three new thermally stable polypyromellitimide films were made by the thermal cyclodehydration of the corresponding polyamic acids obtained by the polymerization of pyromellitic dianhydride with 4,4′-bis{N2-[4-(4-aminobenzyl)phenyl]aspartimido} diphenylmethane, 4,4′-bis{N2-[4-(4-aminophenoxy)phenyl]aspartimido} diphenylether, and bis(4-aminophenoxy)tetrakis (4-phthalamic acid phenoxy)cyclotriphosphazene. The bis(4-aminophenoxy)tetrakis (4-phthalamic acid phenoxy)cyclotriphosphazene was obtained from hexakis(4-aminophenoxy)cyclotriphosphazene involving its reaction with phthalic anhydride. The structure of these materials and precursors were characterized by using Fourier-transform-infrared (FT-IR) and proton nuclear magnetic resonance spectroscopy. The thermal stabilities of the films were evaluated by the thermogravimetric analysis, showing char yields at 800°C ranging from 68% to 58% in a nitrogen atmosphere and 24% in air atmosphere.
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• 5
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3499-3519
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: A kinetic model has been developed and successfully applied to describe the reaction profiles of the seeded emulsion polymerization of styrene. The model incorporated a mechanism for the capture of aqueous-phase oligomeric free radicals by latex particles. Both the collision and diffusion mechanism were considered. The experimental data agreed well with the collision mechanism. The rate of the free radical capture by latex particles is proportional to latex particle surface area (D2p), and also is a strong function of the rate of free radical generation per latex particle. The model predicts that the rate of polymerization is dependent on the latex particle diameter to the 2.5 power in the gel region. This was demonstrated experimentally by J. W. Vanderhoff et al. (J. Polym. Sci., 20, 225 (1956)). Propagation and termination rate constants for styrene in the 70-90°C temperature range were also determined.
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• 6
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2523-2531
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Polyelectrolyte submicron microcapsules were prepared by interfacial crosslinking of an aqueous salt solution of poly(ethyleneimine) and a toluene solution of brominated poly-(2,6-dimethylphenylene oxide). The two solutions were brought together and mixed by sonication. As a result, a stable emulsion was obtained, which was subsequently cast into a membrane in which the microcapsules were embedded. The salt solution contained in the microcapsules could be released under controlled conditions. The rates of release were measured. They could be controlled by applying osmotic pressures, by additional quaternization of the membrane, or by modification of the structure of the capsule wall by introduction of a surfactant.
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• 7
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2501-2521
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: ω-Alkenoic acids, either commercially available or synthesized, were esterified to their corresponding methyl esters. They were characterized by their infrared, 1H-, and 13C-NMR spectra. The ω-alkenoates prepared were: propenoate (acrylic acid), butenoate, pentenoate, hexenoate, heptenoate, octenoate, nonenoate, and decenoate. These compounds were epoxidized with m-chloroperoxybenzoic acid to the corresponding methyl ω-epoxyalkanoates. The rate of epoxidation of the double bond is found to increase as the double bond is separated from the carbomethoxy group by increasing numbers of methylene groups. When at least three methylene groups are inserted, the rate of epoxidation becomes constant and is similar to the epoxidation of ω-olefins. The methyl ω-epoxyalkanoates were characterized by their infrared, 1H-, and 13C-NMR spectra. Methyl ω-alkenoates and methyl ω-epoxyalkanoates were prepared and characterized, and their purification was studied in preparation for their investigation as monomers for olefin or epoxide polymerization using corrdination initiators.
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• 8
Electronic Resource
New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2601-2609
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Data on the ablative photodecomposition of three condensation polymers [polyimide, poly(ethylene terephthalate), and polycarbonate] and one addition polymer (polymethyl methacrylate) by laser pulses at 193 nm are presented. The etch depth/pulse is a linear function of the number of pulses at constant laser fluence. It varies with the logarithm of the fluence in a linear manner at different fluences. The etch depth is independent of the atmosphere above the film, whether it is air at 1 atm, or a vacuum. The etching of PMMA at fluences 〉 100 mJ/cm2 is believed to follow a mechanism different from the process at lower fluences. Etching of polyimide and polyethylene terephthalate at 248 and 308 nm is also reported. The mechanism of etching by laser radiation may receive greater contribution from a thermal process with increasing wavelength. This is manifested in the etch depth versus log fluence plot by sharp changes in slope.
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• 9
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2611-2624
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: In this article we describe a study of the reaction between triethylaluminium (TEA) and ethylbenzoate (BE) in a heptane solution by Fourier transform, infrared (IR), and ultraviolet (UV) spectroscopy. These compounds were chosen as a model of the cocatalytic solution used with a Ziegler-Natta catalyst supported on MgCl2 for the stereospecific polymerization of propene. In the polymerization concentration range a 2 TEA:1 BE yellow complex was added to the solution and no free BE could be detected at a AI/BE molar ratio above 2: the solution contained only free and complexed TEA. The complex decomposed spontaneously to a colorless aluminium alcoholate. The rate of decomposition remained slow at room temperature and the reaction was enhanced by heating or by a high AI/BE ratio or high AI concentration. The decomposition was inhibited in the presence of an olefin.
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• 10
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2945-2952
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Influences of microenvironment of various polyelectrolytes, i.e., ionene polymers and polyamine sulfones, on the photo- and/or thermal isomerization between the trans and cis forms of sodium m-(4-ethoxyphenylazo)benzene sulfonate (SEPS) were studied. 6,6-Ionene demonstrated larger enhancing effect on the cis-trans thermal isomerization than 3,3-ionene, which indicated that the micropolarity or the pH around the polymer is important. In the Arrhenius plots for both photo- and thermal isomerizations, deviations from the linearity were observed. In the former case, a sharp bend and the negative apparent activation energy were obtained at the high temperature. Furthermore, they were sensitively affected by the polyelectrolytes.
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• 11
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2973-2981
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Photocrosslinking of poly(methyl methacrylate) (PMMA) was studied in the solid state in the presence of various quinones. For the study of photocrosslinking mechanism, a PMMA film containing p-benzoquinone (Q) was irradiated with UV light (λ 〉 370nm) and then purified by reprecipitation. It was found that the reprecipitated polymer has quinone-type moieties, besides the hydroquinone-type moieties, chemically bound to the polymer chain. The reprecipitated polymer film also crosslinking efficiency was higher than that of PMMA film containing Q. It was concluded that the formation of quinone-type structure during irradiation played an important role in the photocrossing of PMMA containing Q.
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• 12
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2993-3000
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The oxidation of poly(styryl)lithium with molecular oxygen was investigated in the solid state (with and without N,N,N′, N′-tetramethylethylenediamine) in benzene (with and without N,N,N′, N′-tetramethylethylenediamine) and in benzene/tetrahydrofuran (THF) solutions. The oxidation products included the corresponding polystyrene dimer [(PS)2], the dimeric poly(styrene) peroxide (PSO2PS), poly(styrene) hydroperoxide (PSO2H), and the hydroxyl-terminated polymer (PSOH). The hithertofore unreported macroperoxide (PSO2PS) accounts for approximately 50% of the dimeric product obtained from poly(styryl)lithium oxidations in the presence of Lewis bases. The total amount of peroxide products was determined by iodometric titration in the presence of a phase-transfer catalyst, dicyclohexyl-18-crown-6. On the basis of the effect of polar additives on the amount of dimeric products, it is concluded that dimer formation in the air termination of polymeric organolithium compounds results from oxidation and not carbonation reactions.
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• 13
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3001-3010
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The binding of 41-(1-pyrenyl)butyltrimethylammonium bromide (PN+) to the neutral poly-soap-type polymers poly(vinylbenzo-18-crown-6) (P18C6) and poly(vinylbenzoglyme) (PVBG) was studied by optical spectroscopy and fluorescence in the presence and absence of salts. Measurements of the respective binding constants were based on distinct differences in the optical absorption spectra of free and polymer-bound PN+. When crown ether-compelxable cations (e.g., K+) were added the adsorption of PN+ to P18C6 decreased as the neutral polymer was converted to a polycation. No decrease was found with PVBG because alkali ions do not complex significantly to this polymer in water. PN+ adsorption to both polymers rose rapidly, however, as the salt concentration increased. This effect was strongly anion-dependent and increased in the order of Cl- 〈 Br- 〈 I- 〈 CNS- 〈 BPh4-. The increased binding was reflected in a higher binding constant and also in a larger number of bound PN+ molecules per polymer chain under saturation conditions. It is argued that the formation of ion pairs or larger ion clusters in the aqueous phase when anions are added forces more PN+ molecules to adsorb on the surface of the polymer coil to which they are bound as ion pairs or higher aggregates. Under saturation conditions enough PN+ molecules are bound to convert the pyrene monomer fluorescence spectrum into that of the excimer. These results are compared with data obtained for the anionic solute 4-(1-pyrenyl)butanoate in the presence of salts.
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• 14
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3877-3884
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Polymerization of ethylene was initiated with soluble polystyrene100-butadiene3-Li/TiCI4 complexes in toluene leading to block copolymers. The activity of the system was measured at a constant ratio r = [Li]/[Ti] and for different concentrations in active centers and in monomer. Measurement of the amount of the block copolymers formed led to the direct determination of the efficiency of the catalytic system. This efficiency is defined with respect to the number of potentially active centers and is close to 90%. From both measured values of activity of the catalytic system and of its efficiency, the rate constants of propagation were deduced. The kinetic behavior of the system is fully consistent with that of a living system. The rate is first order towards both ethylene and active centers concentrations. So, the rate constant of propagation is an absolute rate constant, measuring the intrinsic reactivity of active sites. Determination of the absolute rate constant at different temperatures, led to thermodynamic parameters of the propagation reaction. The chemical composition of the complex and the absence of polymeric aggregation, leads to propose a structure of the active species: a bioctahedral binuclear structure is consistent with kinetic, thermodynamic results, and structural determinations.
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• 15
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 121-128
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: To control the swelling of polymer membrane by photoirradiation amphiphilic azoaromatic polymer membranes were prepared and a photoinduced change in the swelling degree of water was investigated. The azobenzene moiety in the side chain of the polymer was isomerized from trans form to cis form by ultraviolet (UV) irradiation and reverse isomerization was found by visible light irradiation. The swelling degree of the polymer membrane for water in the dark was decreased by UV radiation, and when visible light irradiation was carried out in the polymer membrane the degree of swelling recovered to the original level. The swelling degree decreased with an increase in the mole fraction of the azobenzene moiety in the dark and under UV irradiation. The deswelling degree of the polymer membrane by UV irradiation also decreased with an increase in the mole fraction of the azobenzene moiety. This reversible change in the swelling degree was considered to be caused by the photoisomerization of the azobenzene moiety in the polymer membrane.
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• 16
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 129-134
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Several N-substituted chloromaleimides were prepared by dehydrating the corresponding chloromaleamic acids. Treatment of chloromaleimides with allylamine or cyclopropylamine produced N-aryl-2-(allylamino)maleimides and N-aryl-2-(cyclopropylamino)maleimides, respectively. Neither the N-substituted chloromaleimides nor the N-aryl-2-(allylamino) or N-aryl-2-(cyclopropylamino)maleimides polymerized free radically or anionically. The difficulty of achieving good pi-pi overlap and stiric effects at the propagation step prevented the cyclopolymerization of the prepared 1,5-dienes.
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• 17
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 287-293
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: To devise an improved gel permeation chromatography system for the analysis of macromolecules, with a strongly alkaline solution as eluent, three Fractogel TSK gels were investigated. Because primary standards are usually unavailable, calibration was achieved by using Benoit's universal procedure and polystyrene sulfonates, polyethylene glycols, and dextrans as secondary calibrants. Continuous monitoring of intrinsic viscosity resulted from coupling a viscodetector with a classical differential refractometer. It was found that column efficiency and fractionation range could be extended well beyond those of previously studied systems on a reasonably short period of analysis.
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• 18
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 597-604
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: A kinetic study has been made on the preirradiation grafting of acrylic acid (AAc) onto poly(tetrafluoroethylene-perfluorovinyl ether) (PFA) film. The effect of grafting conditions was investigated. The dependences of the grafting rate on preirradiation dose and monomer concentration was found to be of the order of 0.5 and 1.3, respectively. The final degree of grafting was found to increase with dose and monomer concentration. However, it decreases as the grafting temperature increase. The overall activation energy for the graft polymerization was calculated from Arrhenius plots to be 5.6 kcal/mol. The activation energy for this grafting system was found to be independent of preirradiation dose used in the range from 10 to 100 kGy. The relationship between the grafting rate and film thickness gave a negative first-order dependence. The results suggest that the grafting proceeds by radical mechanism with bimolecular termination of growing chain radicals. It was reasonable concluded that this grafting proceeds from the surface to the center of film with progressive monomer diffusion through the grafted layer which swells in the monomer solution.
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• 19
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 609-621
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The kinetics of the formation of polyacrolein microspheres by ionizing radiation (polymer I) were investigated. Their structure and reactivity were compared with polyacrolein microspheres prepared by base catalysis (polymer II). The study of Fourier infrared (IR) spectra of polymers I and II showed structural differences. The reaction of polyacrolein spheres with m-aminophenol indicated the presence of conjugated groups. The reaction of antibodies with polyacrolein spheres was investigated as a function of pH and the number of reactive aldehyde groups was determined by nitrogen analysis of polyacrolein-hydroxylamine adducts. Intensely fluorescent polyacrolein microspheres obtained by Co-γ-irradiation in sizes of 100 Å-4 μm have already found applications as immunoreagents for cell labeling and separation.
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• 20
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 673-677
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: β-Pinene was polymerized with cationic initiators in reactions that were carried out to study the solvent, temperature, initiator, and monomer-to-solvent ratio. Polymers obtained under different conditions were characterized by intrinsic viscosity, softening point, and gel permeation chromatography.
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• 21
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 669-672
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The microstructure of polybutadiene produced by anionic initiation in diethyl ether and tetrahydrofuran with counterions Li+, Na+ and K+ was determined by 1H- and 13C-NMR. Ionization suppressing salts were added in tetrahydrofuran to ensure that only the ion-pair reaction was studied. Results are compared with older published data. In general, the 1,4 content of the polymer increases with increasing counterion size but varies somewhat with solvent with a given counterion. The cis component of the 1,4 structures changes with temperature and counterion. It is suggested that this change reflects the proportion of cis and trans centers that carry the reaction.
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• 22
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 657-667
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Bis-(2,4-dinitrophenyl)glycols are stable in the presence of triethylamine but undergo ethanolysis in the presence of hydroxide ions. The quantitative removal of the DNP blocking group allows an integrated scheme to pure glycols from commercially available polyethylene glycol mixturesMixtures of ethylene glycol oligomers are obtained by anionic polymerization of ethylene oxide. See, for example, G. O. Curme and F. Johnston, Glycols, Reinhold, New York, 1953. They are commercially available (as PEG-200, PEG-400, etc., to indicate the average molecular weight of the major components). by bis-dinitrophenylation, chromatographic separation, and end-group removal, using high performance liquid chromatography (HPLC) of the bis-(2,4-dinitrophenyl)glycols for purity monitoring. A facile synthetic method for the production of penta-to dodecaglycols in a mixed, aqueous, dioxane solvent system, with fair yields, is also described. The bis-(2,4-dintrophenyl) protection of glycols is a reversible reaction that can be used as (1) a preparative method for pure glycols from readily available commercial polyethylene glycol mixtures; (2) a highly sensitive and accurate analytical methodA. Warshawsky, A. Tishbee, and N. Shoef, J. Liq. Chromatogr., submitted for publication. coupled with HPLC.
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• 23
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 721-737
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Ionic groups incorporated into a polymer have a decided effect on its physical properties. A number of ionomers and polyelectrolytes have been widely applied. In particular, sulfonated bisphenol-A polysulfone (SPSF) has been used as a composite or single-component membrane for the desalination of water. In this article, the synthesis and physical characteristics of sulfonated polysulfone are addressed. A detailed synthesis route is provided and methods that yield determinable levels of sulfonation are described. These ion-containing polymers retain an excessive amount of residual salts, which, of course, are impurities to the system. Therefore, before any analyses were made the polymers were subjected to a thorough soxhlet extraction process with boiling water, which appeared to be quite effective. The degree of sulfonation was assessed by several methods such as 1H NMR and FT-IR. A new 1H NMR method was derived because the method cited in the literature proved to be too inconsistent for our work. The new 1H NMR method used a quaternary ammonium counterion [N(CH3)4]. These methyl protons are easily measured and may be ratioed against the isopropylidene protons in the polymer backbone that act as an internal standard. Characterization of the physical properties of SPSF consisted of water uptake, differential scanning calorimetry (DSC), thermomechanical analysis (TMA), and solubility studies. Its physical appearance and mechanical behavior were improved by the solution procedure. Also addressed were the effects of different counterions (Na+ & Mg++) with SPSFs of low levels of sulfonation. The variation in physical properties between the divalent and monovalent counterions is dramatic, especially when observed by TMA in the rubber plateau above the apparent glass temperature.
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• 24
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 769-779
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The radiation graft polymerization of styrene to polyethylene was studied under diffusion-controlled conditions of radiation intensity I, monomer concentration M1, and polymer sample thickness L. The results of the present study together with previous work under diffusion-free conditions verify our theoretical model for the diffusion-controlled reaction. The grafting rate is inverse first order in L for diffusion-controlled reaction and independent of L for diffusion-free reaction. The order of dependence of grafting rate on radiation intensity for diffusion-controlled reaction is one-half that for diffusion-free reaction. Diffusion control leads to a decrease in the order of dependence of grafting rate on monomer concentration. The decrease is greater than theoretically predicted; possible reasons for this effect are described.
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• 25
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 863-864
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
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• 26
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 985-994
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
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• 27
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1035-1042
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Interpenetrating polymer networks (IPNs) with opposite charge groups (tertiary amine and carboxyl groups) made from polyurethanes and methacrylate polymers have been synthesized and their properties and morphology, studied. With increasing carboxyl group concentration the mechanical properties and compatibility between the component networks were significantly improved, possibly because of the negative (or zero) free energy produced by the interaction contribution between the tertiary amine groups in the polyurethanes and the carboxyl groups in the methacrylate polymers determined by differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The improved molecular mixing in these IPNs was thought to be due to the influence of the opposite charge groups in these systems.
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• 28
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1009-1015
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The scandium naphthenate/trialkylaluminum system was investigated as a catalyst in the polymerization of substituted alkynes. Phenylacetylene was converted to a moderately crystalline, high cis polymer. The alkyl-substituted acetylenes produced rubbery or solid materials of relatively high molecular weight. Infrared (IR), ultraviolet (UV), 1H-NMR, and 13C-NMR studies of the polyalkylacetylenes revealed high cis conformation, but apparently twisted from planarity to decrease molecular orbital overlap in the polyconjugated chain.
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• 29
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1043-1053
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 reaction medium on the polycondensation of the tetranitriles of tetracarboxylic acids and diamines has been investigated. The reaction in phenol and cresols yields polymers with macroheterocycles in the chain - polyhexasocyclanes. If phenols with electron-accepting substituents are used as reaction medium, nonmacrocyclic polymers with side aroxyl groups in the chain, polyisoindoxazenes - are formed. The properties of these polymers were studied. Macroheterocyclic compounds formed by condensation of phthalodinitrile with diamines can be used as one of the initial substances in polyhexasocyclane synthesis. Polyamidohexasocyclanes were prepared by polycondensation of macroheterocycles with dicarboxylic acid dichlorides. Some regularities of their formation and their properties were investigated.
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• 30
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1055-1064
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Phosphorus-containing polyamides and polyesters, which had tricyclic fused rings (phenothia-phosphine rings) in the main chain, were prepared and the properties of the resulting polymers were examined. These polymers were obtained at highly reduced viscosities in satisfactory yields by the polycondensation of 2,8-dichloroformyl-10-phenylphenothiaphosphine 5,5,10-trioxide with aromatic diamines or bisphenols. The polyamides and polyesters were soluble in polar aprotic solvents such as dimethylacetamide and N-methyl-2-pyrrolidone; the polyesters were also soluble in chloroform. The polymers exhibited good heat resistance. The phenothiaphosphine-containing polyamides and polyesters self-extinguished immediately when flame was removed and were highly flame-resistant. The polyester obtained from bisphenol A showed a limiting oxygen index value of 43.5.
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• 31
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1077-1084
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Homopolymers of vinylruthenocene and its copolymers with methyl acrylate, styrene, and n-vinylpyrrolidinone have been prepared by free-radical polymerization. No evidence for the electron transfer termination mechanism postulated for polymerization of vinylferrocene was observed. Yields of soluble polymers were 40-90% with Mw (4-25) × 103 and Mw/Mn = 3.0-13.2. TGA analysis showed little weight loss up to 300°C but rapid decomposition above 300°C. Polyvinylruthenocene is a highly brittle material with Tg above 250°C. Torsional braid analysis of the copolymer samples showed Tg in the range 90-130°C which in some samples increased upon cooling and reheating. Several samples showed weak thermal transitions occurring prior to or following Tg. The rise in Tg upon cooling and reheating is indicative of possible decomposition, crosslinking, or realignment of the polymer chains.
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• 32
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1179-1186
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: 2-Vinyl-4,4-disubstituted azlactones were shown to be effective comonomers in free radical addition polymerizations for purposes of subsequently preparing radiation-sensitive materials by attaching an unsaturated nucleophile. The azlactone-functional copolymers could be reacted with amine-, thiol-, and hydroxy-functional nucleophiles over the course of a few hours in solution at room temperature to effect covalent attachment of the nucleophile. The electron beam- and UV-sensitive materials were shown to be useful as photoresist and embossable video disk recording media.
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• 33
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1153-1177
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Asymmetric polyamides from the reaction of either optically active trans-1,2-cyclopropanedicarboxylic acid (C3) or trans-1,2-cyclohexanedicarboxylic acid (C6) with 2,7-diazaspiro[4,4]nonane(DSN) were synthesized. The possible conformations of these polymers and their model compounds in 2,2,2-trifluoroethanol (TFE), water, methanesulfonic acid (MSA), and sulfuric acid were examined by circular dichroism (CD), NMR, viscosity, and dipole moment measurements. The racemic polyamides (±)C3·(±)DSN and (±)C6·(±)DSN exist in extended forms. No intrinsic viscosity changes were observed for these two polymers in TFE and MSA. Certain viscosity and spectral changes have been observed for the optically active polyamides, although no specific ordered conformations can be assigned. The optically active diacid units incorporated into the polymer give a conformation unique from the totally extended chain. CD studies seem to evidence some conformational differences among the polyamide derived from (+)C6 diacid and the optically active DSN. By changing the solvent from TFE to MSA a blue shift of the trough was observed for (+)C6·(±)DSN, a red shift for (+)C6·(-)DSN, and an inversion of the CD spectrum for (+)C6·(+)DSN polyamides. The results of the work with (+)C6·(-)DSN in dilute acid solution suggest that the rotation around the C-N bond is a relatively low-energy process. The spectral and intrinsic viscosity data are consistent with this suggestion. No drastic spectral changes have been observed for the C3·DSN polyamides by changing the solvent from TFE to MSA. The amide group in the C3·DSN polyamide and the corresponding model compound prefer a similar conformation with the carbonyl group bisecting the cyclopropane ring. The C3·DSN polyamide seems to exist in an extended form.
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• 34
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1243-1250
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The rate of reaction of alkyl halides with aqueous sodium acetate or cyanide catalyzed by phosphonium salts supported on insoluble polystyrene resins, and rates of ion-exchange of the chloride ion in the catalysts against the acetate ion, were studied as a function of catalyst particle size, the percentage of ring substitution, the morphology of polymer support, and distance between active site and polymer backbone. Rates of 1-bromooctane or benzyl chloride with macroporous, 7-25% ring-substituted catalysts increased with increasing ring substitution. Rates with macroporous catalysts increased as a heptamethylene spacer was introduced between the active site and the polymer backbone. Rates of ion-exchange with macroporous catalysts were facilitated with increasing ring substitution or by the introduction of the spacer chain. A relation between the catalytic activity of macroporous or microporous catalysts and ion-exchange rates under triphase conditions was discussed.
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• 35
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1251-1258
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Polymerization of the cyclic amide of PIII is described for the first time. The N,N-diethylamine-1,3,2-dioxaphosphorinan was shown to give living reversible polymerization with anionic initiators. Lithium and sodium derivatives were found to be inactive. 1H-, 13C-, and 31P-NMR indicated that the polymer strictly reflects the monomer structure and is formed without any isomerization, the polymer chain being $\rlap{--} ({\rm OP}\left( {{\rm NR}_{\rm 2} } \right){\rm O(CH}_{\rm 2} \rlap{--} )_3 )_n$. Initiation involves attack of the anion on the P atom. From the dependence of the equilibrium monomer concentration on temeprature ΔH1s = 1.5 ± 0.2 kcal·mol-1 and ΔS1s = 4.6 ± 0.6 cal·mol-1·°K-1.
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• 36
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1267-1280
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Copolymers of trans-4-acryloxyazobenzene (AAB) with (-)-menthyl acrylate (MtA) have been prepared by free radical initiation; comonomer reactivity ratios have been found to be rAAB = 0.89 and rMtA = 0.53. Dependence of chiroptical properties on copolymer composition has been investigated and contribution to circular dichroism by azobenzene chromophores of isolated and sequence AAB units, as well as the influence of the trans to cis photoisomerization, have been determined. Kinetics of photoinduced trans → cis and thermally induced cis → trans isomerization of azobenzene side chains have also been examined and the kinetic parameters evaluated with relation to copolymer structure. The results have been discussed in terms of light-induced secondary structure reversible modifications.
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• 37
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New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1259-1265
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Aromatic polyphosphonates of high molecular weights were prepared from phenylphosphonic dichloride and bisphenols having rigid ring structures by the two-phase polycondensation in organic solvent-aqueous alkaline solution system with phase-transfer catalyst at 0°C or below. The effects of reaction solvent and catalyst on the inherent viscosities of the polymers formed are studied. The glass transition temperatures of the polyphosphonates with biphenyl, phenylindane, and diphenylfluorene units are 120, 124, and 188°C, respectively. These polymers are self-extinguishing and are readily soluble in solvents such as N,N-dimethylacetamide, pyridine, tetrahydrofuran, and chloroform. They began to lose weight above 300°C in air. Copolyphosphonates from combinations of bisphenols and phenylphosphonic dichloride are also prepared and characterized.
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• 38
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1299-1307
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Novel polyamides that contain tetrathiafulvalene (TTF) moieties were synthesized by direct polycondensation of Δ2,2′ -bi-1,3-dithiole-4,4′(5′)-dicarboxylic acid with aromatic diamines in the presence of triphenylphosphine, hexachloroethane, and pyridine. Complexes of these polyamides with bromine were TTF cation radical () salts which resulted from the charge transfer of TTF moieties to bromine. The electrical conductivity of undoped polyamides increased with a decrease in diamine length. By doping the bromine the conductivity of the polyamides was enhanced by 3-5 orders of magnitude and reached 10-5-;10-9S cm-1. Maximum conductivity was observed at the doping ratio of [Br]/[repeat unit] 〈 1. The electrical conduction in the bromine complexes may be attributed to the hopping of odd electrons of between TTF moieties.
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• 39
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1309-1318
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The decomposition reaction of hydrogen peroxide by Fe(III)- and Co(III)-2,9,16,23-tetracarboxyphthalocyanine supported on poly(2-vinylpyridine-CO-styrene) and the quaternized one, was studied at pH 7.0 in aqueous media. The kinetics of this reaction was also investigated at pH 7.0 by measuring the initial velocity V0 of the increasing concentration of O2 with a Warburg respirometer. The reaction proceeded according to the catalaselike mechanism. Fe(III)-2,9,16,23-tetracarboxyphthalocyanine supported on poly(2-vinylpyridine-CO-styrene) was a remarkably effective catalyst for a H2O2 decomposition reaction. The coordination sphere around the Fe(III)-phthalocyanine ring was characterized by electronic and ESR spectroscopy. Fe(III)-phthalocyanine supported on the copolymer dispersed in water was the five-coordinated, high-spin type. A typical competitive inhibition in respect of H2O2 by CN- was observed. ESR spectrum of this system showed the low spin iron(III) in the octahedral ligand field. The polymer coils hindered undesirable dimerization of metal-phthalocyanine molecules by the shielding effect.
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• 40
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1319-1325
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Aromatic polysters and copolyesters of high molecular weights with phenylindane units were prepared from combinations of 3-(4-hydroxyphenyl)-1,1,3-trimethyl-5-indanol and bisphenol A with isophthaloyl and terephthaloyl chloride by two-phase polycondensation in a nitrobenzene-water system with various phase-transfer catalysts. The phenylindane-containing polyesters and copolyesters were amorphous and readily soluble in a wide range of solvents that included chloroform, m-cresol, tetrahydrofuran, and dimethylformamide. The glass transition temperatures of the phenylindane-derived polyisophthalate and polyterephthalate were 235 and 253°C, respectively, which were higher than those of the corresponding bisphenol A analogs by some 50°C. These polymers began to lose weight around 400°C in air and nitrogen atmospheres.
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• 41
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1327-1333
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Grafted PMMA was isolated by the acid hydrolysis method. Weight-average and number-average molecular weights were determined by gel permeation chromatography. The number-average molecular weight of the grafted chains was about 475,000 for amylopectin and 403,000 for amylose. The number of grafted chains (mmol) ranged from 2.4 × 10-3 to 4.6 × 10-3 for amylopectin graft copolymers and from 2.9 × 10-3 to 6.8 × 10-3 for those of amylose. These results were related to others obtained from ceric ion consumption studies. The values suggest that amylopectin, because of its complex structure, favors a higher consumption of ceric ion in homopolymerization reactions and inhibits the initiation reactions of the copolymerization.
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• 42
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1335-1347
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Functionalization of an amorphous ethylene-propylene copolymer, EPM, has been performed by means of homogeneous grafting reactions of unsaturated molecules such as dibutylmaleate, diethylfumarate, itaconic anhydride, and maleic anhydride, initiated by free radicals. Dicumylperoxide and dibenzoylperoxide have been used as a free radical source and their efficiency has been compared. A different reactivity of the unsaturated molecules has been evidenced. The influence of the nature of the solvent on the functionalization degree has been investigated, revealing a noticeable effect of the solvent either on the amounts of grafted molecules or on the secondary reactions which lead to partial degradation of the functionalized EPM chains.
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• 43
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1373-1382
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: An attempt was made to produce a new short-chain alphatic polyamide nylon-4,2. This polyoxamide can be prepared by polycondensation of tetramethylene diamine and diethyl oxalate. A high molecular weight polymer (ηinh = 1.9 from 0.5% solutions in 96% sulphuric acid) has been obtained by employing a two-step polycondensation method; the precondensation was carried out in solution at low temperatures (20-140°C) and the postcondensation in the solid state at high temperatures (250-300°C). The effect of solvent composition and reaction temperature on the prepolymerization and the effect of reaction time and temperature on the postcondensation was studied. We also investigated the influence of moisture during washing, storing, and the solid-state reaction on the polymerizability by the postcondensation. Nylon-4,2 is soluble only in highly polar solvents such as trifluoroacetic acid (TFA), dichloroacetic acid, and 96% sulphuric acid. Films were cast from TFA. With these films we studied the IR spectrum, WAXS pattern, water absorption, and melting behavior. Nylon-4,2 was found to melt at 388-392°C, has a crystallinity of 70%, and a low water absorption (3.1% at 50% RH). The glass transition temperature of the dry sample was found to be at ∼120°C and for the wet sample at -15°C.
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• 44
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1383-1392
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Homogeneous copolymers of ethylene and 1-alkenes have been prepared using an ethyl aluminum sesquichloride-vanadium oxychloride catalyst system. Branches were varied from CH3 to C16H33 by appropriate choice of 1-alkene. Size exclusion studies of copolymers of ethylene-d4 and 1-alkenes show that the comonomer content of a given sample is essentially constant over the whole molecular weight range. A random distribution of branches is inferred from the simplicity of the 13C-NMR spectra and from the melting behaviour of the copolymers. Comonomer contents varying from 1 mol% to 15 mol% were readily determined by 13C-NMR spectroscopy. The copolymers can be used to study the separate effects of branch length, branch frequency, and molecular weight on physical properties including melting point and crystallinity.
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• 45
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1419-1433
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: This article describes the synthesis of N,N′-bis(3,3′-maleimidophenyl) sulfone (S) and its Michael addition products with (4,4′-diaminodiphenyl) methane (S-M), 4,4′-diaminodiphenyl ether (S-E), (3,3′-diaminodiphenyl) sulfone (S-DDSm), (4,4′-diaminodiphenyl) sulfone (S-DDSp), (3,3′,3″-tris aminophenyl) phosphine oxide (S-TAP), and 9,9-bis(p-aminophenyl) fluorene (S-B). Curing behavior of these bisimides was investigated by differential scanning calorimetry. Activation energy of curing reaction was determined by using isothermal and multiple heating rate method. Thermal stability of bisimides was evaluated by thermogravimetric analysis. Better char yields were obtained in S-TAP resins.
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• 46
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1461-1470
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: A Comparison between two different feedstocks in the homogeneous polymerization of butadiene has been conducted. The conversion and molecular weight trends were essentially the same for both feedstock systems. Changes in polydispersity at high conversions could not be explained by a living polymerization mechanism. A reaction scheme involving reuse of active cobalt centres combined with termination has been proposed.
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• 47
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1611-1621
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Polyamides 6.10 and 6.6 (PA* 6.10 and 6.6) containing small amounts of —N=N— units in the main chains were prepared by interfacial polycondensation between hexamethylenediamine and sebacoyl chloride or adipoyl chloride with addition of azobiscyanopentanoyl chloride. Polyamide-polystyrene block copolymers (PA-b-PSt) were then prepared by decomposition of the —N=N— units of PA*, initiating radical polymerization of styrene in m-cresol. The average PA block length of PA-b-PSt thus formed was longer than that expected from the initially present PA segments between the —N=N— units. This is probably due to recombination of PA radicals whose initiation efficiency is as low as 15%. The PSt blocks also had higher molecular weight (7000-79,000) in comparison with homopolystyrene produced from monomeric azobiscyanopentanoic acid used as an initiator due to higher viscosity of polymerization system. Variation of intrinsic viscosity and turbidimetric titration behavior along with the change in composition were also discussed.
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• 48
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1699-1705
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The reason for the lower water solubility in W/O microemulsions of the styrene dimer, trans, trans-1,4-diphenyl-1,3-butadiene, in comparison with the monomer was investigated by determining the phase equilibria in the microemulsion system with pentanol as the cosurfactant and sodium dodecyl sulfate as the surfactant. The main factor for the low tolerance for water in the system was the incompatibility of the dimer with the cosurfactant and surfactant.
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• 49
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1865-1873
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The laser-initiated polymerization of a thiol-ene photopolymerizable system was studied. The laser was operated in single- and multiple-pulse modes to generate exotherms, which were measured in a modified differential scanning calorimeter. Arrhenius plots of the polymerization, obtained by measuring polymerization exotherms at various temperatures, showed positive and negative portions. Pseudoactivation energies for the thiol-ene polymerization increased rapidly at low conversions (〈50%) of the thiol and ene chromophores. The results were comparable to those obtained from photopolymerization of multifunctional acrylate monomers.
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• 50
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2005-2016
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: In this article are described the solution properties of ampholytic ionomers obtained by the radical copolymerization of styrene with the ion-pair comonomer 3-methacrylamidopropyltrimethylammonium, 2-acrylamido-2-methylpropanesulfonate. The solution properties were studied in mixed solvents, with a good solvent for the polystyrene backbone and another for the ionic moieties, and in the individual good solvent of benzyl alcohol. The data obtained strongly support extensive intermolecular ionic interactions in solution.
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• 51
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2033-2045
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The effect of absorbed doses of ionizing radiation up to 2MGy in the presence of air on the melting behavior of high- and low-density polyethylene was analyzed from data obtained by differential scanning calorimetry. Thermal measurements were made during the first melting after irradiation. The first melting temperature of polyethylene irradiated in air decreased with increasing absorbed dose. Above approximately 0.6 MGy bimodal endotherms were observed for high-density polyethylene. The heat of fusion remained unchanged after irradiation in air for absorbed doses of less than 2 MGy. Bimodal endotherms were not obtained for low density polyethylene samples irradiated in air. The changes in melting temperature and the appearance of bimodal endotherms are related to the radiation chemistry of polyethylene in the presence of oxygen.
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• 52
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2047-2059
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The β-forming characteristics of poly(S-(2-N-carbazolylethyl)-L-cysteine), (CELC)n, were examined by infrared (IR) spectroscopy. The film of (CELC)39 cast from tetrahydrofuran (THF) showed the typical spectrum of the antiparallel β-form with the amide I band at 1630 cm-1, whereas that of (CELC)200 from dimethylformamide (DMF) or pyridine exhibited the amide I band at 1640 cm-1 which shifted to 1630 cm-1 on heating at 100°C for 5 min. As a result of the examination of the spectral variation due to the degree of polymerization, casting solvents, casting temperatures, and heat treatment, together with the evaluation of interaction constants for intermolecular hydrogen bonds, the band at 1640 cm-1 was attributed to the antiparallel-chain pleated sheet (designated as β′-form) with weaker hydrogen bond strength than that of the usual antiparallel β-form. The β′-β-transformation is discussed in terms of the rigidity of the side-chain region.
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• 53
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2017-2032
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The effect of ionizing radiation on the melting behavior of high-density and low-density polyethylene was examined with data obtained by differential scanning calorimetry. Melting temperatures and fusion endotherms were obtained after absorbed doses of gamma radiation up to 3 MGy. The changes in melting temperatures and heat of fusion for the first and second meltings are related to the radiation chemistry of polyethylene. The changes in the first melting temperature are caused by radiation-induced links that decrease the melt entropy and increase the flod surface free-energy-per-unit area of chain-folded polyethylene crystals. These effects are dependent on the lamellar thickness distribution and on the types of links formed (intramolecular or intermolecular). The changes in melting temperature and heat of fusion obtained in the second melting are related to the inhibition of crystallization caused by the presence of radiation-induced links.
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• 54
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2061-2082
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: A series of polyethyleneimine derivatives and their oligomer models with pendant thymine or adenine bases separated by β-alanyl groups as spacers were prepared by an activated ester method. To elucidate the nature of intramolecular interaction of thymine and adenine bases ultraviolet (UV) spectrophotometric studies were undertaken for the series of compounds and the results were compared with those obtained for the corresponding oligomers without spacers. In the thymine derivatives, the nature of the intramolecular interaction resembled that of the corresponding compounds without β-alanyl units, although larger hypochromicities were found in the series with β-alanyl units. In the adenine derivatives, contrary to the corresponding thymine systems, UV hypochromicities of the compounds decreased by incorporation of the spacer group into side chains. It became evident that the intramolecular interaction of adenine bases was due to stacking neutral species, hydrogen bonding, and residual hypochromicity for the protonated species.
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• 55
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Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2105-2121
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Aromatic bispropenyl ethers are a new class of highly reactive thermosetting monomers that have been prepared and characterized. Two synthetic routes to their preparation have been developed. The first of these involves the base-catalyzed isomerization of bisallyl ether precursors that gives predominantly the Z bispropenyl ether isomers. The second method employs tris(triphenylphosphine)ruthenium(II) dichloride as an isomerization catalyst and produces predominantly the E isomers. Using these methods, a number of bispropenyl ether monomers containing different aromatic groups have been synthesized. The cationic polymerization of these novel monomers to give crosslinked network polymers using diaryliodonium salts as photo and thermal initiators has been studied.
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• 56
Electronic Resource
New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2255-2263
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The effects of hydrogen on both degree and rate of polymerization have been determined for continuous, gas phase polymerization of propylene at industrial reactor conditions. The effects of molecular weight using three modifications of TiCl3-DEAC catalyst are correlated by Natta's equation, using number average molecular weights determined from polymer melt flow rate. The coefficients of Natta's equation, when correlated against temperature in Arhenius plots, imply that the most active catalyst is diffusion controlled because the activation energy is abnormally low. Hydrogen increases overall polymerization rate. Rate is correlated by modification to Natta's equation that accounts for hypothesized increase in active sites on catalyst surface due to adsorbed molecular hydrogen.
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• 57
Electronic Resource
New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2243-2253
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The kinetic model given by Marten and Hamielec that describes the bulk polymerization of methyl methacrylate (MMA) and accounts for diffusion-controlled termination and propagation was modified to include termination by combination and reaction diffusion and was then tested using isothermal conversion/time and molecular weight data obtained dilatometrically at various temperatures and with three different initiators. For each series of measurements two adjustable parameters were fitted to the conversion/time data. Excellent fits were obtained and the adjustable parameters were found to be the same for all concentration levels of the three initiators and to vary in a simple manner with temperature. The predicted molecular weight averages and molecular weight distributions were in satisfactory agreement with those found experimentally considering the difficulty of measuring high molecular weight PMMA by GPC. This model thus satisfies the specifications for a polymer reactor model that can be used to optimize commercial production systems.
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• 58
Electronic Resource
New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2275-2279
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Type of Medium: Electronic Resource
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• 59
Electronic Resource
New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2661-2666
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: ESCA has been used to investigate the composition and structural features of plasma-polymerized 2,4,6-trifluoro-1,3,5-triazine. Polymer formation was studied as a function of power and post-polymerisation treatment. All the polymer films revealed an intense peak at a binding energy of ∼290.2 eV probably arising from groups. A high sensitivity towards hydrolysis was observed resulting in substantial loss of fluorine and increase in oxygen content of the plasma polymers.
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• 60
Electronic Resource
New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2685-2697
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The kinetics of chain transfer to the bifunctional initiating and transfer agents (binifers) 1,4-di(2-chloro-2-propyl)benzene (p-DCC), 1,3-di(2-chloro-2-propyl)-5-tert-butylbenzene (m-tBuDCC), and 1,3-di(2-chloro-2-propyl)-4,6-dimethylbenzene (m-DMeDCC) in the polymerization of isobutylene has been investigated. Chain transfer to monomer was shown to be absent up to -20°C in CH3Cl/n-hexane and CH2Cl2/n-hexane mixtures using the m-tBuDCC/BCl3 binifer system. Chain transfer constants (Ci) to m-tBuDCC and kt/kp ratios determined in the range from -30°C to -80°C in CH3Cl/n-hexane mixtures and pure CH3Cl solvent are reported, and the activation energy differences Etr,l - Ep and Et - Ep were calculated. Chain transfer constants to p-DCC and m-DMeDCC were determined by the use of pure CH3Cl diluent at -50°C. The chain transfer reactivity of five different inifers is discussed and compared based on CI values obtained under identical conditions, with special regard to the new, sterically hindered binifer m-DMeDCC of extraordinary reactivity.
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• 61
Electronic Resource
New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2817-2828
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: A method to immobilize enzymes photochemically with use of photocrosslinkable poly(vinylalcohol) bearing stilbazolium groups is described. Irradiation of a film of the photosensitive polymer containing enzyme gave water-insoluble, cellophane-like transparent film demonstrating high enzyme activity. The dissolution of enzymes from the film was dependent upon the molecular weight of the proteins and the content of the photocrosslinking unit. It was found that various enzymes are sufficiently entrapped in the photocrosslinked polymer matrix when the content of the photosensitive group is more than about 1.0 mol%.
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• 62
Electronic Resource
New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2841-2858
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: To provide suitable monomers for a study designed to synthesize copolymers containing alternating sequences of nucleic acid base pairs, the following electron-donor monomers were synthesized: 9-(2-vinyloxyethyl)adenine, 1-(2-vinyloxyethyl)thymine, and 1-(2-vinyloxyethyl)-cytosine. The following electron-acceptor monomers were also synthesized: 9-(2-maleimidoethyl)adenine, 1-(2-maleimidoethyl)thymine, and 1-(2-maleimidoethyl)cytosine. The methods of synthesis are described along with their characterization by the usual methods, and their physical properties are reported. A variety of novel compounds were required as intermediates in the above identified syntheses. This paper also includes characterization of these compounds and a report of their physical properties.
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• 63
Electronic Resource
New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2871-2886
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Reactions of PVC with three representative stabilizers Bu2SnY2 (Y = OCOC11H23, SCH2COOCH2CH(Et)CH2CH2CH2CH3, OCOCH=CHCOOMe) in solution and under nitrogen were studied by two principal methods. First, using stabilizers with radioactive labels in the Y groups, the uptake of these groups by virgin and degraded polymer was measured. The UV-visible absorption spectra of the stabilized polymers are discussed. Second, the effect of these three stabilizers on the rate of elimination of hydrogen chloride from heated PVC was studied. It is shown that the effects of HCI-scavenging and of exchange reactions in suppressing the evolution of HCI can be separately evaluated. The thermal decomposition of dibutyltin bis(methyl maleate) to give maleic anhydride is reported. Interpretation of the observations is made in terms of assessing the relative importance of the various polymer-stabilizer reactions in promoting stabilization.
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• 64
Electronic Resource
New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2923-2930
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: A soap/alcohol miniemulsion in combination with an homogenized mixture of monomer and initiator is utilized to generate PVC plastisol. Droplet distributions generated consist of two distinct types. Judicious control of soap-to-alcohol ratio allows control of the number and size of the smaller droplet family; homogenization and initiator water solubility affect the other. Final latex particle distribution may be unimodal or bimodal depending upon manipulation of these factors.
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• 65
Electronic Resource
New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3149-3160
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: The ring-opening, nucleophilic addition of amine-terminated oligomers to alkenyl azlactones was exploited to prepare reactive, that is, in free radical polymerizations, oligomers that could be used in 100% solids resin systems. Acrylamide-functional oligomers resulted from the reaction that used 2-vinyl-4,4-dimethylazlactone, whereas methacrylamide-functional oligomers were produced with 2-isopropenyl-4,4-dimethylazlactone. The overall reaction took place under mild conditions, for example, a few hours at room temperature, and was particularly free of side reactions. Examination of reaction rates with the two alkenyl azlactones revealed that the 2-vinyl derivative reacted ca. four times faster. The (meth)acrylamide-terminated resins were characterized by IR, NMR, and molecular weight analyses.
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• 66
Electronic Resource
New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3217-3224
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Evidence of the initiation process during uncatalyzed thermal polymerization of vinyl monomers is presented. DSC studies reveal a prominent endothermic effect just before the polymerization exotherm, which is substantiated by the identification of the free radicals produced in the initiation by a quick quenching technique and subsequent detection by ESR at low temperatures.
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• 67
Electronic Resource
New York : Wiley-Blackwell
Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3263-3288
ISSN: 0360-6376
Keywords: Physics ; Polymer and Materials Science
Source: Wiley InterScience Backfile Collection 1832-2000
Topics: Chemistry and Pharmacology
Notes: Cationic copolymerization of 1,3,5-trioxane with methyl 10,11-epoxyundecanoate or methyl 7,8-epoxyoctanoate and terpolymerization with 1,3-dioxolane was successfully carried out. Co-and terpolymerization of 1,3,5-trioxane with 4-(1-carbomethoxynonyl)-1,3-dioxolane was also achieved. Feed compositions of the functional comonomers were varied from 5 to 40 mol %; in all cases the isolated copolymers contained less than 5% of the functional mer units. The composition of the copolymers showed that the methyl ω-epoxyalkanoates were much less reactive than 1,3,5-trioxane. A similar trend was observed with the functional dioxolane monomer, although significantly shorter induction periods were observed in comparison with the epoxy/trioxane copolymerizations. The oxymethylene copolymers and terpolymers were characterized primarily by their infrared spectra; however, the thermal and base stabilities of selected copolymers were also determined.