| 摘要 |
A polymer blend comprises (1) a polyurethane rubber and (2) a graft polymer of one or more conjugated diolefines, a vinyl aromatic hydrocarbon or alkyl derivative thereof and vinyl cyanide or an alkyl derivative thereof. The polyurethane rubbers used are obtained by reacting a polyisocyanate with an organic polyhydroxy compound of moderately high molecular weight, the following preparations being exemplified: (2) an ethylene glycol-monoethanolamine-adipic acid polyesteramide is reacted with 1,6-diisocyanato-hexane and then cold-cured with diisocyanato diphenylmethane, (3)a hydroxyl terminated polyethylene adipate is reacted with 1,5-diisocyanato naphthalene to yield a product which is cross-linkable with water, (4) hydroxyl terminated polyethylene adipate is reacted with 1,4-diisocyanato benzene and the resulting polymer cured by heating with 1,5-diisocyanato naphthalene, and (5) polytetramethylene ether glycol is reacted with 2,4-tolylene diisocyanate to yield a product which is first chain-extended by the addition of water and then cured by heating with a further quantity of the diisocyanate. The graft polymer used is preferably one prepared by polymerizing a mixture of acrylonitrile and styrene in a latex of polybutadiene. Other diene polymers specified are those derived from isoprene, dimethylbutadiene, pentadiene1,3 and methyl derivatives thereof and hexadienes, either alone or in admixture with each other or with butadiene. Alkyl styrenes specified are alpha-methyl styrene, vinyl toluenes and alpha-methyl toluenes. Alkyl vinyl cyanides specified are methacrylonitrile and ethacrylonitrile. The blends may be made by milling the polymeric components together with, if desired, the addition of a siliceous filler. |
