Abstract: The invention disclosed herein includes a process for producing highly amorphous polypropylene and a highly amorphous polypropylene produced by this process comprising contacting propylene with (1) a catalyst comprising a titanium compound supported on a rare earth halide and (2) a metal alkyl cocatalyst wherein the metal is selected from the group consisting of groups II and III of the Periodic Table under conditions for producing a highly stereo- and regio-irregular amorphous propylene polymer.

Abstract: The invention relates to a process for the controlled polymerization of alpha-olefins selected from the group consisting of propylene and butylene in order to form a polymer containing by weight about 10% to 30% isotactic polyolefin, 25% to 70% atactic polyolefin and 0% to 65% by weight of an amorphous ethylene/olefin copolymer which process comprises combinations of the steps of:(a) homopolymerizing the alpha-olefin at a temperature of from about 0.degree. C. to about 90.degree. C. (preferably from about 20.degree. C. to about 60.degree. C.) in the presence of a high yield catalyst comprising a titanium compound supported on activated MgCl.sub.