| 摘要 |
The present invention is concerned with a polyethylene composition comprising a base resin having a density of more than 952.0 kg/m 3 and equal to or less than 957.0 kg/m 3 , wherein the composition has a melt flow rate MFR 5 of 0.12 to 0.21 g/10min and the polyethylene composition has a polydispersity index PI within the range of higher than 4.9 Pa -1 and equal to or less than 9.0 Pa -1 . Furthermore, the present invention concerns a polyethylene composition obtainable by a multistage process, the multistage process comprising polymerizing ethylene in the presence of a silica supported Ziegler Natta catalyst in a reactor cascade comprising a first loop reactor, a second loop reactor and a gas phase reactor for obtaining the base resin and then extruding the base resin together with stabilizers and carbon black into the polyethylene composition. Furthermore, the present invention relates to an article, such as a pipe, made from the polyethylene composition and the use of the polyethylene composition for the production of such an article. |
