Process for the production of soluble high molecular weight
polyurethanes which are free from isocyanate groups
    4.
    发明授权
    Process for the production of soluble high molecular weight polyurethanes which are free from isocyanate groups 失效
    生产不含异氰酸酯基团的可溶性高分子量聚氨酯的方法

    公开(公告)号:US4039516A

    公开(公告)日:1977-08-02

    申请号:US674355

    申请日:1976-04-07

    IPC分类号: C08G18/00 C08G18/08

    CPC分类号: C08G18/0852

    摘要: This invention relates to an improved process for the production of high molecular weight polyurethanes which are free from isocyanate groups and are soluble in organic solvent in reduced reaction times. The reactants, polyol and isocyanate, for example, are mixed together with solvent and the temperature is permitted to rise under the effect of the heat of reaction. The reaction mixture is then cooled with solvent addition in such a way that the viscosity of the reaction mixture remains constant until the optimum temperature for the polyurethane formation reaction ("specific reaction temperature") is reached. The mixture is then gradually cooled until there is no residual isocyanate present and the polymer is recovered from the reaction mixture.

    摘要翻译: 本发明涉及一种制备高分子量聚氨酯的改进方法,它们在反应时间缩短的情况下不含异氰酸酯基并且可溶于有机溶剂。 将反应物,多元醇和异氰酸酯例如与溶剂混合在一起,允许温度在反应热的作用下升高。 然后将反应混合物用溶剂加入冷却,使得反应混合物的粘度保持恒定,直到达到聚氨酯形成反应的最佳温度(“特定反应温度”)。 然后将混合物逐渐冷却,直到不存在残留的异氰酸酯,并且从反应混合物中回收聚合物。