Process for producing propylene block copolymer
AssigneeSumitomo Chemical Company, Limited
InventorYasuki Fujiwara
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Abstract
A production process of a propylene block copolymer, comprising the steps of (I) contacting a solid catalyst component containing titanium atoms, magnesium atoms and halogen atoms with an organoaluminum compound and an external electron donor represented by the defined formula, thereby forming a polymerization catalyst, (II) polymerizing propylene in the presence of the polymerization catalyst, thereby forming a polymer component (1) having an intrinsic viscosity, [η]1, and (III) copolymerizing propylene with an olefin other than propylene in the presence of the polymer component (1), thereby forming a polymer component (2) having an intrinsic viscosity, [η]2, which is three times or more [η]1.
Claims6
A process for producing a propylene block copolymer, comprising the steps of:
- (I) contacting a solid catalyst component containing titanium atoms, magnesium atoms and halogen atoms with an organoaluminum compound and an external electron donor represented by following formula (i), thereby forming a polymerization catalyst;
- (II) homopolymerizing propylene or copolymerizing propylene with an olefin other than propylene in the presence of the polymerization catalyst, thereby forming a polymer component (1) containing 90% by weight or more of propylene units, and having an intrinsic viscosity, [η]1, of 1.0 dl/g or less, the total of polymer component (1) being 100% by weight;
- and
- (III) copolymerizing propylene with an olefin other than propylene in the presence of polymer component (1), thereby forming a polymer component (2) containing 10 to 90% by weight of propylene units, and having an intrinsic viscosity, [η]2, of 1 to 10 dl/g, which is three times or more the total of polymer component (2) being 100% by weight,
- R1Si(OC2H5)3 (i)
- wherein R1 is a hydrocarbyl group having 3 to 20 carbon atoms, whose carbon atom linked directly to the silicon atom is a secondary carbon atom.
Dependencies are inferred from the claim text.