Accession Number : AD0690742

Title :   THE EFFECT OF MICROTACTICITY ON THE GLASS TEMPERATURE OF POLY (ALPHA-METHYL STYRENE),

Corporate Author : NATIONAL RESEARCH COUNCIL OF CANADA OTTAWA (ONTARIO) DIV OF APPLIED CHEMISTRY

Personal Author(s) : Cowie,J. M. G. ; Toporowski,P. M.

Report Date : 22 NOV 1968

Pagination or Media Count : 9

Abstract : The effect of microstructure on the glass temperature T(g) of poly(alpha-methyl styrene) has been investigated. It has been observed that T(g) increases as the syndiotacticity of the molecule increases-thus T(g) = 446K for polymer with 67% syndiotactic placements, while a value of T(g) = 453K is found for a sample with 95% syndiotactic placements. Coefficients of expansion for the liquid and glassy states have been calculated and from these a chain stiffness parameter has been estimated using the Gibbs-DiMarzio theory. The result indicates that the flex energy of the alpha-methyl styrene chain is about 20% larger than for the polystyrene chain. (Author)

Descriptors :   (*STYRENE PLASTICS, *TRANSITION TEMPERATURE), MICROSTRUCTURE, HYDRODYNAMICS, STEREOCHEMISTRY, DIFFERENTIAL THERMAL ANALYSIS, ACRYLIC RESINS, CANADA

Subject Categories : Plastics

Distribution Statement : APPROVED FOR PUBLIC RELEASE