| 摘要 |
A process for the preparation of oxidised polyethylenes by oxidising finely divided low density polyethylene at elevated temperatures by means of an oxidation gas comprising air and/or oxygen, in which from 0.015 to 0.5% by weight of a free radical-forming organic compound has been admixed with the polyethylene and an oxidation gas containing from 30 to 600 mg, in particular from 80 to 300 mg, of ozone per kg of polyethylene is introduced per hour, and in which completion of the oxidation at elevated temperature is followed, if desired, by vacuum treatment. The oxidised polyethylenes are used as lubricants in the extrusion of polyvinyl chloride. |
