The present invention concerns a process for producing a propylene polymer nucleated with a polymeric nucleating agent containing vinyl compound units. The method comprises modifying a catalyst by polymerizing a vinyl compound in the presence of said catalyst in a medium, which does not essentially dissolve the polymerized vinyl compound, and by continuing the polymerization of the vinyl compound until the concentration of unreacted vinyl compounds is less than about 0.5 wt-%. The thus obtained modified catalyst composition is used for polymerizing propylene optionally together with comonomers to produce in the presence of said modified catalyst composition. Modification of the catalyst according to the present invention will reduce production costs and provide highly reliable catalyst activity.
申请公布号
DE69801236(T2)
申请公布日期
2002.05.16
申请号
DE1998601236T
申请日期
1998.11.09
申请人
BOREALIS TECHNOLOGY OY, PORVOO
发明人
KARBASI, AMIR;LESKINEN, PAULI;JAEAESKELAEINEN, PIRJO;MALM, BO;PITKAENEN, PAEIVI;HAERKOENEN, MIKA;HAUGEN, JOHN