| 摘要 |
Improved polyurethane compositions of matter are prepared by reacting a prepolymer and a polyol in the presence of suitable catalysts to produce materials which cure rapidly and through chemical bonding, are adapted to provide covering protection for surfaces made of various substances and prevent electrolysis of conductive substances. The steps in the preparation of these improved polyurethane compositions generally provide for the reaction of higher molecular weight diols with isocyanates at an elevated temperature to insure completion of reaction and then reducing the temperature to inhibit premature formation of cross linkages in the preparation of prepolymers. The polyols used in the reaction with such prepolymers are novel in that such polyols contain chain extenders, polyfunctional polyalkylene polyols, tertiary alkanolamines, and relatively high molecular weight polyalkylene ethers.
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