| abstract |
A process for producing a propylene copolymer comprises copolymerizing propylene, a C4-C18 alpha -olefin and optionally ethylene in the presence of a catalyst system comprising (i) titanium trichloride obtained by a method comprising reducing titanium tetrachloride with an organoaluminum compound and reacting the reduced solid with a complexing agent and a halogen compound, and (ii) an organoaluminum compound. A multilayer polypropylene film comprises a crystalline polypropylene film layer, and a propylene copolymer film layer, said propylene copolymer being a propylene copolymer containing about 10 to 30% by weight of C4-C18 alpha -olefin and about 0 to 5% by weight of ethylene and having a cold xylene-soluble polymer content of 15% by weight or less. |