| 摘要 |
1306696 Elastomeric polyurethanes SCHMITT & ZIEGLER 3 June 1970 [3 June 1969] 26784/70 Heading C3R Elastomeric polyurethanes are prepared by reacting in a one-shot process, in the presence of a cross-linking catalyst, a polyol obeying the rule <SP>M</SP>/ n-1 # 2000 wherein M is the molecular weight of the polyol and n is the number of hydroxyl groups in the polyol, with a monomeric polyisocyanate, at least one of the polyol and polyisocyanate being tri- or higher functional, a filler in amount of more than 60% by weight of elastomer and filler also being incorporated in the reaction mixture. The polyol is preferably a polyether triol having a molecular weight of at least 4000. The polyisocyanate may be diphenylmethane-4,4<SP>1</SP>-diisocyanate or diphenyl-4,4<SP>1</SP>-diisocyanate. Suitable fillers are barium sulphate, quartz powder, glass powder, asbestos, soot or a pigment. The catalyst may be diethyl tin dilaurate. The filled elastomers may be used in the manufacture of sealing rings and discs, seatings, beddings, paddings for preventing sliding of carpets, bumper and shock absorber elements and electrical insulation. |
