PROCESS FOR PRODUCING POLYPROPYLENE HAVING IMPROVED STRETCHABILITY

摘要

SO-1-24080C/80 A process for producing polypropylene having improved stretchability by polymerizing propylene in the presence of a catalyst system composed of (A) titanium trichloride obtained by reducing titanium tetrachloride with an organoaluminum compound and reacting the reduced solid with a complexing agent and a halogen compound simultaneously or successively and (B) an organoaluminum compound is disclosed. In the process, ethylene is supplied to the polymerization system together with propylene so that the ethylene content in the resulting polymer is in the range of from 0.1 to 1.0 wt%.