| 摘要 |
The present invention relates to a polyolefin composition with increased resistance to degradation caused by ClO 2 -containing water and to an article made of such a polyolefin composition. The polyolefin composition comprises a polyolefin base resin (A), at least one antioxidant (B) having an initial oxygen induction time (OIT 190°C ) of more than 35 min., determined according to the OIT 190°C test described herein and having a slope of the curve, when OIT 190°C , in minutes, is recorded as a function of exposure time, in minutes, in a chlorine dioxide degradation test as described herein, of at least -0.07, and c) at least one antioxidant (C) having an initial oxygen induction time (OIT 190°C ) of not more than 35 min., determined according to the OIT 190°C test described herein and having a slope of the curve, when OIT 190°C , in minutes, is recorded as a function of exposure time, in minutes, in a chlorine dioxide degradation test as described herein, of less than -0.07, wherein said polyolefin composition shows a resistance against water containing 10 ppm chlorine dioxide at 70 °C and a pH of 6.8 ± 0.1 of at least 450 min., expressed as the time to reach 50% of the initial oxygen induction time at 210 °C (OIT (210°C),50% ) , determined according to the chlorine dioxide degradation test as described herein. The present invention further relates to the use of the polyolefin composition for the production of an article, e.g. a pipe, a fitting or a storage container and to the use of the polyolefin composition for increasing the resistance of an article against degradation caused by contact with ClO 2 -containing water. |
