Bp Chemicals Limited

Edward Quentin Clutton

Philip Stephen Hope

Stephen Roy Partington

John Norman Reid Samson

Polyethylenes are prepared having a density in the range 900-980 kg/m and a weight average molecular weight &gE;375,000 characterized by a fracture toughness at &minus;40&deg; C. >20 kJ/m and a dynamic viscosity of <3000 Pa.s at 100 rad/sec. The polymers also having a die swell of 10-80% and show a desirable combination of physical and processing properties. The polymers are prepared by the use of catalysts comprising a metallocene component and a Ziegler component.

Polymer compositions

A polyethylene having the following properties: an annealed density D/weight average molecular weight M relationship defined by the equation D>1104.5M , and a Charpy Impact I/High Load Melt Index H relationship defined by the equation I>35.OH . Also, a polyethylene film having the following properties: a density of at least 957 kg/m ; a Dart Impact of at least 130 g; and a polydispersity of less than 12. Both may be made using a tridentate nitrogen-containing transition metal polymerization catalyst.

Growing community of inventors

Edinburgh, United Kingdom

Edward Quentin Clutton