| 摘要 |
PURPOSE:To improve curability and mold releasability, by using a specified polyol in producing the titled elastomer by reaction injection molding of a polyisocyanate and a high-MW polyol containing a chain extender. CONSTITUTION:Use is made of a high-MW polyol wherein at least 80wt% (preferably, about 100wt%) is composed of a mixture of about 95pts.wt. or below polyoxyalkylene diol (average MW, per functional group, of 1,000-2,500, the oxyethylene group content <=about 25wt%, and the content of oxyethylene groups on the terminals of oxyethylene chains >=5wt%) and about 5pts.wt. or above high-functionality polyoxyethylene polyol having an average functionality >=about 4 (average MW, per functional group, of 1,000-3,000 and the content of oxyethylene groups on the terminals of oxyethylene chains >=5wt%).
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