Syndiotactic crystalline copolymers of propylene.

摘要

Essentially syndiotactic crystalline copolymers of propylene with minor proportions of 1-butene, endowed with good mechanical properties, lowered melting point and limited solubility in xylene at 25 DEG C and the process for their preparation by polymerizing mixtures of propylene with 1-butene, by using catalysts obtained from stereorigid and chiral zirconium and hafnium compounds and from polymethylalumoxane compounds.