A novel heat-curable liquid polymer composition comprises a modified urethane oligomer containing terminal ethylenic unsaturation and a free radical catalyst. It is prepared by heating a mixture of the oligomer and the catalyst. In a preferred embodiment, the polymer composition further includes a reinforcing agent and/or a filler; the cured composition demonstrates enhanced impact properties and is particularly useful in automotive body constructions.
The urethane oligomer has an equivalent ratio of NCO to OH from 0.5:1 to 2:1 and has been prepared by reacting
(a) an isocyanate-terminated prepolymer having a final free NCO content ranging from 0.5% to 30% and that is the product of reacting an organic polyisocyanate with an isocyanate-reactive-group-containing unsaturated acrylate and/or unsaturated amide monomer, with
(b) a polyol having an average equivalent weight in the range 75 to 500 and an average functionality of at least about 3.
一种新型热固化液态聚合物组合物由一种含有末端
乙烯不饱和的改性聚
氨酯低聚物和一种自由基催化剂组成。其制备方法是加热低聚物和催化剂的混合物。在一个优选的实施方案中,聚合物组合物还包括增强剂和/或填料;固化后的组合物具有更强的抗冲击性能,尤其适用于汽车车身结构。
聚
氨酯低聚物的 NCO 与 OH 的当量比为 0.5:1 至 2:1,通过以下反应制备而成
(a)
异氰酸酯封端预聚物,其最终游离 NCO 含量为 0.5%至 30%,该预聚物是有机多
异氰酸酯与含
异氰酸酯反应基团的不饱和
丙烯酸酯和/或不饱和酰胺单体反应的产物。
(b) 多元醇,其平均当量重量在 75 至 500 之间,平均官能度至少约为 3。