摘要:

AbstractA series of polyguanidines was prepared by the polyaddition reaction of biscarbodiimides with diamines. The polyaddition reaction was carried out in solution. The polymers thus obtained had intrinsic viscosities up to 0.84 and molecular weights up to 15000. The structure of the polymers was identified by comparison of their infrared spectra with those of model compounds, elementary analysis, and a study of the reaction conditions. Thermogravimetric study indicated that the polyguanidines decomposed over 170°C under nitrogen. The polyguanidines were highly resistant to hydrolytic degradation by strong acid or alkali. The polyguanidines had basic groups and formed stable hydrochloric salts when they were treated with hydrochloric acid

ISSN:0449-296X    

DOI:10.1002/pol.1969.150070301

出版商:John Wiley&Sons, Inc.    

年代:1969

数据来源: WILEY

摘要:

AbstractPolyisobutylene was decomposed at 325, 345, and 365°C under vacuum, and the volatile products were trapped by using liquid nitrogen. The products, C1–C24hydrocarbons, were analyzed by gas chromatography. The formation of the main products is discussed on the basis of a free‐radical mechanism. Intramolecular radical transfer can account for the production of most fragments including dimers, trimers, tetramers, and so on, of isobuty

ISSN:0449-296X    

DOI:10.1002/pol.1969.150070302

出版商:John Wiley&Sons, Inc.    

年代:1969

数据来源: WILEY

摘要:

AbstractSmoluchowski's theory has been modified and the improved theory was applied to diffusion‐controlled polymerization. This application proved that the rate‐controlling process is not transrational diffusion but the segmental diffusion. The segmental diffusion‐controlled rate constant was derived by the collision theory. This rate constant explains the experimental fact that the diffusion‐controlled rate constant of bimolecular termination in radical polymerization of alkyl methacrylate is inversely proportional to solution viscosity and independent of the molecular weight of the polymeric free

ISSN:0449-296X    

DOI:10.1002/pol.1969.150070303

出版商:John Wiley&Sons, Inc.    

年代:1969

数据来源: WILEY

摘要:

AbstractPolyhydrouracils and polyiminoimidazolidinones were prepared by ring formation along the chain of appropriately substituted polyureas. Cyclization of 2‐carbomethoxy‐ethyl‐substituted polyureas in a polyphosphoric acid medium gave the polyhydrouracils. The polyurea precursors were prepared fromN,N′‐bis(2‐carbomethoxyethyl)‐1,6‐hexanediamine andN,N′‐di(2‐carbomethoxyethyl)‐1,4‐cyclohexanebis(methylamine) with methylenebis(4‐phenyl isocyanate), 2,4‐toluene diisocyanate, and 3,3′‐dimethoxy‐4,4′‐biphenylene diisocyanate. These polyureas were soluble inm‐cresol, dimethylformamide, and chloroform, had inherent viscosities of up to 0.8, and could be cast into tough films. The polyhydrouracils had similar physical properties and could also be cast into films. The polyhydrouracils melted at temperatures 100–150°C higher than their polyurea precursors. Polyiminoimidazolidinones were prepared by cyclization of α‐cyanoalkyl‐substituted polyureas in the presence ofn‐butylamine. The intermediate polyureas, which were not isolated, were prepared from methylenebis(4‐phenyl isocyanate) withN,N′‐bis(1‐cyanocyclohexyl)‐1,6‐hexanediamine,N,N′‐bis(1‐cyanocyclohexyl)‐m‐xylylenediamine andN,N′‐bis(1‐cyanocyclopentyl)‐1,6‐hexanediamine. The polyiminoimidazolidinones were soluble inm‐cresol, dimethylformamide, and chloroform and had low inherent viscosities of 0.14–0.28. Thermogravimetric analyses showed that the polyhydrouracils underwent rapid decomposition at 400°C, whereas an analogous unsubstituted polyurea decomposed at 300°C. On the other hand, the polyi

ISSN:0449-296X    

DOI:10.1002/pol.1969.150070304

出版商:John Wiley&Sons, Inc.    

年代:1969

数据来源: WILEY

摘要:

AbstractPolymerization of 2‐methyl‐1‐vinylimidazole (MVI) and 2‐ethyl‐1‐vinylimidazole (EVI) was found to be markedly photosensitized in the presence of oxidizing metal salts such as UO2(NO3)2, Ce(NH4)2(NO3)6, Hg(CH3COO)2, AgNO3; non‐oxidizing metal salts such as ZnIIdid not act as photosensitizers. The interaction of monomer with a metal salt is discussed on the basis of infrared and electronic spectroscopy. This photopolymerization is very specific with respect to the kind of monomer. The polymerization of noncomplexing monomer (styrene) is not photosensitized by these metal salts. Consequently, photosensitized electron transfer between monomer and metal salt via complex formation is considered to be the most probable initiation mechanism. Cupric acetate and sodium chlorolaurate, which have been reported as efficient initiators for the polymerization of vinylpyridine andN‐vinylcarbazole, respectively, act as linear terminators of growing radicals. The radical polymerizability of the zinc complex of MVI was studied by means of copolymerization with styrene. The reduction of the reactivity of MVI on complexing was explained by correlating with the spectroscopic observations. Because the polymerization system is heterogeneous, a detailed discussion w

ISSN:0449-296X    

DOI:10.1002/pol.1969.150070305

出版商:John Wiley&Sons, Inc.    

年代:1969

数据来源: WILEY

摘要:

AbstractA new class of coordination polymers, polybis(phosphinato)fluoroalanes, [Al(F) (OPRR′O)2n], where R,R′ are alkyl, phenyl, or benzyl, was prepared and studied. The properties of these polymers are influenced by the phosphinate (R) substituents; polymers havingn‐alkyl groups with more than five carbons are flexible and exhibit unusual hydrolytic stability. A polymer was obtained with a degree of polymerization of 104 by incorporating a 2:1 ratio of benzyl(n‐heptyl) and di‐n‐octyl phosphinate groups. The properties of the flexible materials are consistent with linear rather than highly crosslinked or network systems. Feasible structures are proposed for t

ISSN:0449-296X    

DOI:10.1002/pol.1969.150070306

出版商:John Wiley&Sons, Inc.    

年代:1969

数据来源: WILEY

摘要:

AbstractThe radical polymerizability of vinylpyridines in the presence of cobaltous chloride was studied in DMF solution, and the results were correlated with the spectroscopic data obtained for methanol solution. In general, the behavior of vinylpyridine complexed with cobaltous chloride is qualitatively the same as that of zinc complexes reported previously. The rates of polymerization were enhanced by the addition of cobaltous chloride when 4‐vinylpyridine(4‐VP) or 2‐methyl‐5‐vinylpyridine(MVP) was the monomer, whereas the polymerization of 2‐vinylpyridine(2‐VP) was retarded by cobaltous chloride. The monomer reactivity of all the vinylpyridines was also enhanced by complex formation as studied by copolymerization with styrene. The enhancement of reactivity of 4‐VP complexed with cobaltous chloride is somewhat smaller than that of the correspondi

ISSN:0449-296X    

DOI:10.1002/pol.1969.150070307

出版商:John Wiley&Sons, Inc.    

年代:1969

数据来源: WILEY

摘要:

AbstractN‐(Hydroxyalkyl) β‐alanine ester which was obtained from amino alcohol and acrylate yielded polyamide at room temperature in the presence of a basic catalyst. Alkali and alkali earth metal alkoxides had a strong catalytic effect on the room‐temperature polycondensation ofN‐(hydroxyethyl)‐β‐alanine esters. The catalytic activity of metal alkoxides decreased in the order: Li>Na>K>Cs and Ca>Zn>Mg. Aluminum and titanium alkoxide had a weak catalytic effect, while boron (III), tin (IV), antimony (V), and tellurium (VI) alkoxides did not show any catalytic activity for the polycondensation. It was also found that solvent had an effect on the course of the polycondensation ofN‐(hydroxyethyl)‐β‐alanine esters, and the highest molecular weight polymer was formed only in methanol solution. The solid‐phase polycondensation of the low molecular weight prepolymer resulted in a high molecular weight polymer with an inherent viscosity of 1.0 in the presence of a catalytic amount of phosphoric acid. The polymer obtained is hydrophilic and its moisture absorption is more than

ISSN:0449-296X    

DOI:10.1002/pol.1969.150070308

出版商:John Wiley&Sons, Inc.    

年代:1969

数据来源: WILEY

摘要:

AbstractSaturated and unsaturated aliphatic polyurethane were obtained from three different routes. In route 1, 1,4‐dichloro‐2‐butene, sodium cyanate, and methanol were reacted to give dimethyl 2‐butene‐1,4‐dicarbamate. This is hydrogenated easily to give dimethyl butane‐1,4‐dicarbamate. Ester exchange reaction of this compound with glycol gave saturated aliphatic polyurethane. In another procedure, route 2, 1,4‐dichloro‐2‐butene, sodium cyanate and excess glycol were reacted to give bis(ω‐hydroxyalkyl)‐2‐butene‐1,4‐dicarbamate. This was hydrogenated to give bis(ω‐hydroxyalkyl)‐butane‐1,4‐dicarbamate. A glycol elimination reaction gave poly(polymethylene tetramethyl‐enedicarbamate). By route 3, 1,4‐dichloro‐2‐butene, sodium cyanate, and glycol were reacted to give poly(polymethylene 2‐butene‐1,4

ISSN:0449-296X    

DOI:10.1002/pol.1969.150070309

出版商:John Wiley&Sons, Inc.    

年代:1969

数据来源: WILEY

摘要:

AbstractThe rate of bulk polymerization of styrene initiated by silver salt–organic halide systems was measured at 0°C. Neither of the catalyst components initiated the polymerization when used alone, while combined catalysts containing both components initiated the polymerization in the case that the components reacted with each other with precipitation of silver halide. The rate in the early stage of the polymerization increased with an increase in reaction time. Plots of yield against the second power of time gave a linear relation in the early stage of the polymerization. The slope of the line was taken as a measure of catalytic activity. The catalytic activity was markedly influenced by the kinds of the components. The activities of silver perchlorate–organic halide systems increased in the following order of halides: chloride

ISSN:0449-296X    

DOI:10.1002/pol.1969.150070310

出版商:John Wiley&Sons, Inc.    

年代:1969

数据来源: WILEY