| 摘要 |
<p>1302966 Polyurethanes DYNAMIT NOBEL AG 29 April 1970 [30 April 1969] 20713/70 Heading C3R Polyurethanes are prepared by reacting a polyisocyanate with a polyol in the presence of an organic vanadium compound as catalyst and in the absence of water, the organic vanadium compound being soluble in the reaction mixture and being (1) a compound of the general formula (Y) m V(YR) a-2m , wherein Y is an oxygen or sulphur atom; a is 4 or 5; m is 0 or 1 when a is 4 and m is 1 when a is 5; and each group R is the same or different and is a straight or branched chain alkyl group which may contain one oxygen or sulphur atom between two carbon atoms of the group, a cycloalkyl group, an aralkyl group, an alkaryl group or an aryl group, and/or (2) a complete or partial intermolecular condensation product obtainable by the intermolecular elimination of RYH, in which R and Y are defined above, from a compound having the above general formula in the presence of water; and/or (3) a complete or partial intermolecular condensation product obtainable by the intermolecular elimination of a compound having the general formula RYH, from such an intermolecular condensation product in the presence of water. The polyurethanes may be foamed by incorporation in the reaction mixture of halogenated alkanes or alkenes. Conventional polyisocyanates and polyols, particularly polyethers, are used. In specific examples, the vanadium catalysts used are vanadyl triisopropylate, vanadyl tri-n-butylate, vanadyl triisobutylate, vanadyl tri-tert. butylate, vanadyl tricyclohexandate, vanadyl trimethylglycolate and vanadyl triphenolate.</p> |
