Method of stabilizing polyoxymethylene copolymer
    4.
    发明授权
    Method of stabilizing polyoxymethylene copolymer 失效
    稳定聚甲醛共聚物的方法

    公开(公告)号:US4814424A

    公开(公告)日:1989-03-21

    申请号:US120314

    申请日:1987-11-13

    CPC分类号: C08G2/36

    摘要: An improved method of stabilizing a polyoxymethylene copolymer, which comprises(1) heat-melting a crude copolymer of trioxane and a cyclic ether and/or a cyclic acetal to form a first stabilized copolymer having a decomposition ratio (D.sub.220.sup.60), determined when it is heated at 220.degree. C. for 60 minutes in vacuum, of up to 2% by weight, and then(2) bringing the first stabilized copolymer into contact with steam containing 0.01 to 5% by weight of a basic compound at a temperature of at least 100.degree. C. but not exceeding the melting point of the copolymer to form a second stabilized copolymer.

    摘要翻译: 一种稳定聚甲醛共聚物的改进方法,其包括(1)将三恶烷和环醚和/或环缩醛的粗共聚物加热熔融以形成具有分解比(D22060)的第一稳定共聚物,当其为 在220℃下真空加热60分钟,最多达2重量%,然后(2)使第一稳定的共聚物与含有0.01至5重量%碱性化合物的蒸汽在温度为 至少100℃,但不超过共聚物的熔点以形成第二稳定的共聚物。