Isotope Effect on the Isothermal Crystallization Behavior of Isotactic Polypropylene Blends between the Deuterated and Hydrogenated Species

Abstract

The effect of isotope on the isothermal crystallization behavior has been investigated for a series of isotactic polypropylene blend samples between the hydrogenated and deuterated species by using the thermal analysis technique. The analysis based on the Avrami equation revealed the crystallization rate constant k and Avrami exponent n, which were found to change systematically with the D/H content at the same degree of supercooling, reflecting the cocrystallization phenomenon of these two species. The k value was appreciably higher for the D species than for the H species. Correspondingly, the spherulite size, observed by polarized optical microscope and small-angle light scattering, was found to be larger for the blend with higher H content.