Preparation of polysiloxane block polymers and their use as foam
inhibitors
    2.
    发明授权
    Preparation of polysiloxane block polymers and their use as foam inhibitors 失效
    聚硅氧烷嵌段聚合物的制备及其作为泡沫抑制剂的用途

    公开(公告)号:US4396524A

    公开(公告)日:1983-08-02

    申请号:US218575

    申请日:1980-12-22

    摘要: This invention is directed to a method of preparing block copolymers useful as foam inhibitors, which method comprises the steps of:(1) mixing (a) from 100 parts by weight of a polydimethylsiloxane that is liquid at 20.degree. C., and (b) from about 2 to 20 parts by weight of a spatially cross-linked polysiloxane resin with a molecular weight of from about 1000 to 10,000;(2) heating said mixture in the presence of a catalyst until the viscosity is at least 200 mPa.s, as measured at 20.degree. C., to form a block polymer;(3) mixing said block polymer with (c) from about 0.5 to 15 parts by weight of a silicon dioxide aerogel; and(4) heating the mixture from step (3).

    摘要翻译: 本发明涉及一种制备用作泡沫抑制剂的嵌段共聚物的方法,该方法包括以下步骤:(1)将(a)100重量份在20℃下为液体的聚二甲基硅氧烷和(b )约2至20重量份的分子量为约1000至10,000的空间交联聚硅氧烷树脂; (2)在催化剂存在下加热所述混合物,直到在20℃下测得的粘度至少为200mPa.s以形成嵌段聚合物; (3)将所述嵌段聚合物与(c)约0.5-15重量份的二氧化硅气凝胶混合; 和(4)加热来自步骤(3)的混合物。