| 摘要 |
PURPOSE:To prepare a urethane resin compsn. which gives a cured molding with a high softening point and a superior heat and moist heat resistance, and suitable for producing a belt, by compounding a specific urethane prepolymer and a specific curing agent mixture. CONSTITUTION:A urethane prepolymer obtd. by reacting trans-cyclohexane-1,4- diisocyanate with a polytetramethylene ether glycol with an average MW of 1000-2000 in a molar ratio of NCO to OH of 1.8-2.2, is compound with a curing agent mixture comprising diethyltoluenediamine (A) and 3,3'-dichloro-4,4'- diaminodiphenylmethane (B) in an equivalent ratio of A to B of (1:8)-(1:2) to give a urethane resin compsn. The resulting compsn. gives a cured molding with a softening point of 250 deg.C or higher and a superior heat and moist heat resistance, and is suitable to produce a belt used under a high load at a high temp. |
