| 摘要 |
PURPOSE:To obtain the title copolymer with both high rigidity and impact strength and good influidity by stepwise copolymerization between propylene and ethylene using a catalyst comprising an organoaluminum compound and a reaction product from a Mg compound, Ti compound, Si compound and Al compound. CONSTITUTION:Using a catalyst made up of (A) a contact product from (1) a contact product from a polysilicon compound of formula I (R<1> is hydrocarbon) and magnesium dihalide, titanium tetralkoxide and/or polymer therefrom, (2) a silicon compound of formula II (R<2> is branched chain hydrocarbon; R<3> and R<4> are each hydrocarbon; 1<=n<=3), (3) a second silicon compound of formula III (R<5> is H or hydrocarbon; X is halogen; 0<=a<=4) and (4) an organoaluminum compound and (B) an organoaluminum compound, propylene or propylene/ ethylene mixture is polymerized in the absence of solvent, and the propylene/ ethylene mixture is further polymerized, thus obtaining the objective copolymer with the polymerization ratio (weight ratio) propylene/ethylene of (70:30)-(30:70) containing 20-70wt.% of a rubbery copolymer (20 deg.C xylene solubles). |
