Concepedia

Abstract

Isotactic poly(propylene)s with 60–80% vinyl chain-end selectivity were synthesized with metallocene catalysts. Some of these vinyl-terminated poly(propylene)s are highly stereoregular (mmmm pentads up to 95%) and have high crystalline melting points in the range of 140–150°C. Chain-end analysis using 13C NMR indicates the vinyl chain-ends in the polymer are most likely formed through β-methyl elimination in the chain termination step.