| 摘要 |
The present invention relates to an olefin polymerization process, wherein propylene and a C4 to C10 α-olefm monomer, preferably 1-butene- and optionally ethylene are reacted in the presence of a Ziegler-Natta catalyst so as to obtain a polypropylene, wherein the polypropylene comprises C4 to C10 α-olefm, prefrablyl-butene-derived comonomer units in an amount of from 0,5 to 15 wt% and ethylene-derived comonomer units in an amount of 0 to 3 wt%, and wherein the Ziegler-Natta catalyst comprises i) an external donor of the formula (I): (R3)z(R2O)ySi(R1)x and ii) a solid catalyst component being free of external carrier material. |
