Amorphous Polyolefins: The Relations between Molecular Structure, Submolecular Motion and Mechanical Behavior.
Technical rept. Sep 69-Aug 71,
PRINCETON UNIV N J DEPT OF CHEMICAL ENGINEERING
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The thermomechanical spectra of two series of amorphous polyolefins represented by CH2m-CCH32n and CH2m-CCH3C2H5n where m 1, 2, and 3, are presented from -180C to a point above the glass transition temperature. The polymers were obtained by cationic polymerization of alpha-olefins. The mechanical spectra show a maximum in glass transition temperature and secondary transition temperature for the second member of each series. This maximum is interpreted in terms of a proposed intermolecular interlocking considered to be at a maximum for the second member of the series, and serving to restrict the submolecular motions associated with the transitions. The proposal is discussed in terms of its consequences upon free volume, density, cohesive energy density, and chain flexibility. Author