Alumina-based aerogel supported transition metal catalyst useful as a Ziegler-Natta olefin polymerization catalyst and process for preparing same

Claim 1

A process for the polymerization and copolymerization of alpha-olefins which comprises contacting an alpha-olefin at a temperature and at a pressure sufficient to initiate the polymerization and copolymerization with a catalytic amount of (a) a di(C 1 -C 18 alkyl) chloroaluminum compound or a tri(C 1 -C 18 alkyl) aluminum compound; and (b) a catalyst produced by the reaction of a transition metal compound formed from members selected from the group consisting of titanium, vanadium, hafnium, and zirconium and from members selected from the group consisting of chlorides, oxychlorides, alkoxychlorides and oxyalkoxychlorides with a heat-activated alumina based aerogel having a morphology by transmission electron microscopy comprising thin film-like structures and having a bulk density less than about 0.10 g/cm 3 , a BET surface area greater than about 300 m 2 /g and a pore volume greater than about 3 cm 3 /g and obtained by heating an alumina-based aerogel having a carbon content at a temperature of at least about 400° C., in the presence of oxygen, for a time sufficient to produce said heat activated alumina-based aerogel substantially free of carbon; said alumina-based aerogel being prepared by venting a C 1 -C 5 alcohol or mixture of same, under supercritical conditions, from a mixture comprising a hydrolyzable aluminum compound, water, and a C 1 -C 5 alcohol.