Patent ID: 9650458
Date: 2017-05-16
CPC Classifications: C08F

Claim:
1. A propylene terpolymer comprising comonomer units derived from ethylene and 2.5-15% by weight 1-butene, obtained by a process comprising the step of copolymerizing propylene and ethylene in the presence of a catalyst system comprising the product obtained by contacting the following components: (a) a solid catalyst component comprising a magnesium halide, a titanium compound having at least a Ti-halogen bond and at least two electron donor compounds, one of which being present in an amount from 40-90% by mol with respect to the total amount of donors, wherein the first electron donor is selected from succinates and the second electron donor is selected from 1,3-diethers, (b) an aluminum hydrocarbyl compound, and (c) optionally an external electron donor compound; wherein the terpolymer has the following features: