Accession Number : AD0283457

Title :   STUDY OF THE MOLECULAR STRESS RESPONSE OF SOLID POLYMERS BY PHOTOELASTIC METHODS

Descriptive Note : Quarterly progress rept. no. 1, 30 Jun-30 Sep 60,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE

Personal Author(s) : Andrews,R. D. , Jr

Report Date : 23 APR 1962

Pagination or Media Count : 6

Abstract : The effect of stereospeci ic structure on photoelastic behavior of solid polymers was studied. Stress-optical coefficients of several polymers were measured at several temperatures. Isotactic, syndiotactic, and stereo-block polymethyl methacrylates were compared a d showed small, but definite differences. Isotactic and atactic polystyrene also showed a small but definite difference in stress-optical coefficient. T e sign of the stress-optical coefficient for polymethylACRYLATE AN POLYMETHYL METHACRYLATE IN THE GLASSY STATE IS OPPOSITE, +7 and -4 Brewsters, respectively. The stress-optical coefficient of polymethyl methacrylate becomes more negative with decreasing molecular weight.

Descriptors :   *PHOTOELASTICITY, *POLYMERS, ACRYLIC RESINS, BUTYL RADICALS, METHYL RADICALS, MOLECULAR WEIGHT, STRESSES, STYRENES

Distribution Statement : APPROVED FOR PUBLIC RELEASE