Patent ID: 9051404
Filing Date: 2015-06-09
Classification: C08F,C08L,C09J

Abstract:
1. A process for preparing a multi-component copolymer comprising a semi-crystalline component having a crystallinity of 20% or more, and an amorphous component having a crystallinity of 5% or less, wherein the copolymer comprises at least 80 wt % of units derived from propylene and from 1 wt % to 20 wt % of at least one comonomer selected from a group consisting of hexene-1 and octene-1, the process comprising: (a) polymerizing propylene and one or more of the comonomers in a first reaction zone in the presence of a first catalyst system capable of producing the semi-crystalline component having a crystallinity of 20% or more; and (b) contacting the semi-crystalline component of step (a) with additional propylene in a second reaction zone separate from the first reaction zone and in the presence of the first catalyst system and a second catalyst system to produce said copolymer, the second catalyst system capable of producing the amorphous component having a crystallinity of 5% or less; wherein the first catalyst system comprises di(p-triethylsilylphenyl)methylene(cyclopentadienyl)(3,8-di-t-butylfluorenyl)MR, where M is zirconium or hafnium and R is Cl or CH wherein the copolymer has a viscosity at 190° C. of 530 to 1500 mPa sec, a heat of fusion between 20 and 50 J/g, a branching index of 0.764 to 0.95 as measured at z-average molecular weight, an elongation of 400 to 1434.5%, and a toughness of 7 to 53 megajoule/m wherein the weight averaged molecular weight of the semi-crystalline component is from 5,000 to 100,000; wherein the semi-crystalline component is incorporated into the amorphous component so as to form a branched cross-product with both amorphous and semi-crystalline characteristics; and wherein the weight ratio of the semi-crystalline component to the amorphous component is from 90:10 to 30:70.