| 摘要 |
1,084,336. Stabilizing polyurethanes with disulphides. DUNLOP RUBBER CO. Ltd. June 10, 1964 [July 2, 1963], No. 26121/63. Addition to 976,901. Heading C3R. A polyurethane contains, as an antioxidant, a xanthogen disulphide compound of formula ROCS-SS-SCOR 1 where R and R 1 each represent an alkyl group, an alicyclic group, an aralkyl or aryl group. The antioxidant may be present in amount 0À01- 5% and may be e.g. dimethyl, diisopropyl, diisobutyl or diamyl xanthogen disulphide and may be added at any stage during the preparation of the polyurethane. The polyurethane may be obtained by reacting a polyol, e.g. polyether, with a polyisocyanate or polyisothiocyanate. In the example, hexamethylene diisocyanate was added in two stages to polytetramethylene ether glycol followed by trimethylolpropane, dibutyltin dilaurate and diisopropyl xanthogen disulphide. |
