Patent ID: 8304361

Claim:
A supported phosphinimine catalyst having a productivity in a gas phase polymerization greater than 2500 g of polymer per gram of supported catalyst per hour normalized to 1379 kPag (200 psig) of ethylene partial pressure and a temperature of 90° C. as measured in a 2 liter reactor over a period of time from 0 to 60 minutes comprising: i) a calcined porous particulate inorganic oxide support having an average particle size from 30 to 80 microns, a surface area greater than 250 m 2 /g, and a pore volume greater than 0.3 ml/g; and ii) from 0.1 to 30 weight % based on the weight of said calcined support of an aluminum compound of the formula R 12 2 AlO(R 12 AlO) q AlR 12 2 wherein each R 12 is independently selected from the group consisting of C 1-20 hydrocarbyl radicals and q is from 3 to 50; and iii) a phoshpinimine catalyst of the formula: wherein M is selected from the group consisting of Ti, Zr and Hf; PI is a phosphinimine ligand of the formula: wherein each R 21 is independently selected from the group consisting of a C 1-10 hydrocarbyl radicals; L is a monoanionic ligand selected from the group consisting of a cyclopentadienyl ligand which is substituted at the 1 position by a C 1-6 straight chained alkyl radical and at the 2 position by a C 6 F 5 radical; Y is independently selected from the group consisting of activatable ligands; m is 1 or 2; n is 0 or 1; p is an integer and the sum of m+n+p equals the valence state of M; to provide from 0.020 to 0.031 mmol of M per g of catalyst and the weight ratio of aluminum from the aluminum compound to M from the phosphinimine catalyst from 50:1 to 150:1.