Oxymethylene polymer molding compositions provide articles which exhibit enhanced impact strength properties, especially at low temperatures such as -20°F(-29°C), when such compositions include an elastomeric polyurethane, which is the reaction product of certain proportions of:
(i) 4,4'-methylenebis (phenyl isocyanate),
(ii) polyoxytetramethylene glycol having a molecular weight of 1500 to 3000, and
(iii) at least one diol extender selected from aliphatic straight chain diols having 2 to 6 carbon atoms, bis (2-hydroxy-ethyl) ether of hydroquinone, and bis (2-hydroxy-ethyl) ether of resorcinol.
氧亚甲基聚合物模塑组合物提供了具有增强冲击强度特性的物品,尤其是在低温条件下,如-20°F(-29°C),当这种组合物包括弹性聚
氨酯时,弹性聚
氨酯是一定比例的下列物质的反应产物:..:
(i) 4,4'-亚甲基双(苯基
异氰酸酯)、
(ii) 分子量为 1500 至 3000 的聚氧化四亚乙基二醇,和
(iii) 至少一种二元醇扩展剂,选自具有 2 至 6 个碳原子的脂肪族直链二元醇、
对苯二酚的 双(2-羟基-乙基)醚和
间苯二酚的双(2-羟基-乙基)醚。