Accession Number : AD0694297

Title :   DETECTION OF MICROSTRUCTURE VARIATIONS IN POLY Alpha-METHYL STYRENE BY DENSITY GRADIENT ULTRACENTRIFUGATION,

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 : 09 OCT 1968

Pagination or Media Count : 7

Abstract : It has been demonstrated that the various tactic forms of poly alpha-methyl styrene can be distinguished by measurement of polymer density or partial specific volume. Density gradient ultracentrifugation has been shown to be a useful and sensitive technique for detecting such differences, but the results emphasize the necessity to use the method for comparative rather than absolute determination of the apparent specific volume. Differences in the apparent specific volume between atactic and highly syndiotactic poly alpha-methyl styrene were observed in a benzene-bromoform gradient, but the use of a methyl cyclohexane-1-iodo-octane gradient was marred by excessive preferential adsorption. (Author)

Descriptors :   (*STYRENES, MOLECULAR STRUCTURE), MICROSTRUCTURE, DENSITY, ORGANIC SOLVENTS, BENZENE, CYCLOHEXANES, POLYMERS, ULTRACENTRIFUGES

Subject Categories : Plastics
      Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE