SULFUR-CURED POLYURETHANES BASED ON A POLYESTER PREPARED FROM AZELAIC ACID, DIMER ACID AND LOWER ALKANE GLYCOLS

摘要

Sulfur-curable polyester urethane crude rubbers having improved hydrolysis resistance and excellent properties when exposed to low temperatures over a long period of time are prepared by the reaction of an organic diisocyanate with a polyester prepared from an acid mixture having 90/10 to 97/3 preferably 94/6 mole ratio of azelaic acid to a long chain dibasic acid and a polyol mixture having a 65/35 to 75/25 preferably 70/30 mole ratio of 1, 4-butanediol to propylene glycol followed by chain extension with a polyol having pendant aliphatic unsaturation.