A PROCESS FOR THE PREPARATION OF HIGH PERFORMANCE POLYPROPYLENE

摘要

A process for the preparation of high performance polypropylene is provided, in which the propylene polymer with broad molecular weight distribution is prepared in two or more stages with different H2 level in various stages in the presence of the catalysts with high activity and high stereospecificity. The stereospecificity of the catalytic active centres is regulated or controlled in order to improve the heterogeneity of molecular chain stereo-regularity,that is, in order to make the lower molecular weight portion of the polymer have higher stereo-regularity and make the higher molecular weight portion of the polymer have lower stereo-regularity. ® KIPO & WIPO 2009