Accession Number:

AD0420049

Title:

BIREFRINGENCE OF POLYOLEFINS,

Descriptive Note:

Corporate Author:

MASSACHUSETTS UNIV AMHERST POLYMER RESEARCH INST

Personal Author(s):

Report Date:

1962-12-31

Pagination or Media Count:

21.0

Abstract:

Recently Tsvetkov3 has published birefringence curves for polypropylene fractions of differing tacticity and has shown that the more tactic samples exhibit negative birefringence but that atactic samples exhibit positive strain-birefringence both at very small strains less than 1. He proposes that the difference in sign of the photo-elastic contributions of the amorphous and crystalline fractions permit their separation. Measurements in this laboratory confirm Tsvetkovs experimental results. Additional measurements of the time dependence of these effects and of x-ray diffraction support a different interpretation in which the crystalline regions may contribute either positively or negatively to the birefringence. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE