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39. Heterocyclic polyesters

Author

Korshak, V. V., Vinogradova, S. V., Pankratov, V. A., Pavlova, S. A., and Timofeeva, G. I.

Abstract

1.The strength indices of films of fractions of polyarylates based on isophthalic acid and bis (4-hydroxyphenyl)methane and 9,9-bis(4-hydroxyphenyl)fluorene, produced by various methods, decrease with increasing temperature.2.With increasing molecular weight, the breaking strength and relative elongation at breaking of polyarylate films increase, while the modulus of elasticity decreases only up to a definite value of the molecular weight.3.Films of polyarylates, produced by polycondensation in a high-boiling solvent, possess better mechanical indices than films of polymers synthesized by interfacial polycondensation.4.The influence of the nature of substituents at the central carbon atom of the initial bis-phenols upon the mechanical properties of polyarylates was considered.

Published
1967
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40. Heterochain polyesters

Author

Korshak, V. V., Vinogradova, S. V., Pankratov, V. A., and Baskakov, A. N.

Abstract

Summary 1.Homogeneous and mixed polyarylates were synthesized from 4,4'-benzylidenediphenol, 4,4-(diphenylmethylene) diphenol, hydroquinone, dian, and terephthaloyl and isophthaloyl chlorides.2.The question of the effect of the structures and compositions of the starting substances of the properties of the polyarylates was discussed.3.Mixed polyarylates based on 4,4'-benzylidenediphenol and 4,4'-(diphenylmethylene)diphenol are distinguished by good solubility in many available organic solvents.4.The presence in polyarylates of bulky phenyl side groups in the 4,4'-benzylidenediphenol and 4,4'-(diphenylmethylene) diphenol residues considerably lowers the degree of crystallinity of the polymers.

Published
1964
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44. NEW SYNTHESES OF POLYBENZIMIDAZOLES

Author

FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OHIO, Korshak,V. V., Vinogradova,S. V., Pankratov,V. A., FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OHIO, Korshak,V. V., Vinogradova,S. V., and Pankratov,V. A.

Abstract

Polybenzimidazoles were synthesized from adipamide dihydrochloride, diethyl diiminoadipate dihydrochloride and 3,3' -diaminiobenzidine, and also from adiponitrile and 3,3' -diaminobenzidine tetrahydrochloride both in melt and in N-methylphrolidinone solution. The melting temperatures and the solubilities of poly prepared by these methods approached those of polybenzimidazoles of a similar structure prepared from diphenyl adipate and 3,3' -diamino-benzidine. The polymers are light-brown powders soluble in sulfuric and formic acids, dimethylformamide, dimethylsulfoxide, dimethylacetamide, and other solvents. The reduced viscosity of 0.5 percent solution of the polymers in formic acid at 25 degrees C was 0.5 dl/g. The structure of the polymer was confirmed by IR-spectroscopy and elemental analysis. (Author), Edited trans. of Vysokomolekulyarnye Soedineniya. Seriya B (USSR) v10 n7 p481-482 1968, by L. Thompson.

Published
1969

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