Polyolefin composition the maximum value of molecular weight is present in the composition portion with a maximum comonomer content

摘要

A polyolefin copolymer composition, which is produced with a catalyst having a metallocene complex in a single reactor by polymerisation of an ~a-olefin with one or more olefin comonomers, has long-chain branches along the polymer backbone and a molecular weight maximum that occurs in the 50 wt.% of the composition having the highest wt.% content of comonomer. Also claimed are: (1) an organometallic polymerisation catalyst suitable for the continuous gas-phase copolymerisation of 1-hexene and ethylene in a molar ratio of 0.02 or less at 70 deg C and an ethylene pressure of 8 bar to produce a composition of density 0.918 g/cm3 and having long-chain branches and/or a molecular weight maximum as above; (2) a film or other article made from a copolymer as above having a melt strength greater than 4 cN, or a seal strength greater than 1.9 kg, or a hot-tack greater than 0.23 kg, or a dart impact strength greater than 100g; and (3) a blend of 2 or more resins comprising (A) 1-99 wt.% of a copolymer made by the above process and (B) 99-1 wt.% of other resins.