Process for the preparation of carbonic acid esters of polyester-polyols
    31.
    发明授权
    Process for the preparation of carbonic acid esters of polyester-polyols 失效
    聚酯多元醇碳酸酯的制备方法

    公开(公告)号:US4191705A

    公开(公告)日:1980-03-04

    申请号:US845174

    申请日:1977-10-25

    CPC分类号: C08G63/64 C08G63/916

    摘要: The present invention relates to a process for the preparation of carbonic acid esters of polyester-polyols by transesterifying the polyols with carbonic acid aryl esters at elevated temperatures under vacuum in the presence of a catalyst. The reaction conditions are controlled to avoid the formation of by-products and the chain extension of the polyester-polyols. The present invention is also concerned with the polyester carbonic acid esters so formed, their use in producing polycarbonate block copolymers and the copolymers so produced. The copolymers may be produced by transesterifying the polyester carbonic acid esters with bisphenols and subjecting the bis-hydroxyaryl carbonates so formed to normal polycarbonate synthesis such as interfacial or melt polycondensation.

    摘要翻译: 本发明涉及一种通过在催化剂存在下在真空下在升高的温度下将多元醇与碳酸芳酯酯交换而制备聚酯多元醇的碳酸酯的方法。 控制反应条件以避免副产物的形成和聚酯多元醇的链延长。 本发明还涉及如此形成的聚酯碳酸酯,它们在生产聚碳酸酯嵌段共聚物中的用途以及如此制备的共聚物。 共聚物可以通过将聚酯碳酸酯与双酚酯交换并使如此形成的双羟基芳基碳酸酯进行正常的聚碳酸酯合成如界面或熔融缩聚来制备。

    (Meth)-acrylic acid esters
    36.
    发明授权
    (Meth)-acrylic acid esters 失效
    (甲基) - 丙烯酸酯

    公开(公告)号:US4752338A

    公开(公告)日:1988-06-21

    申请号:US858402

    申请日:1986-05-01

    CPC分类号: A61K6/083 C08F20/36

    摘要: (Meth)-acrylic acid esters of the formula ##STR1## in which R.sup.1 and R.sup.2 are each independently hydrogen, chlorine, fluorine or a C.sub.1 - to C.sub.4 -alkyl radical andR.sup.3 and R.sup.4 are identical or different and represent the group ##STR2## wherein Y is a divalent bridge member from the group ##STR3## and Z is a straight-chain or branched hydrocarbon chain which has 2 to 10 carbon atoms, can optionally contain oxygen bridges and is optionally substituted by 1 to 4 acrylate or methacrylate radicals,whereinR.sup.5 represents hydrogen or methyl andR.sup.6 represents hydrogen, C.sub.1 -C.sub.6 - alkyl or phenyl,which are useful as dental materials.

    摘要翻译: (甲基)丙烯酸酯,其中R 1和R 2各自独立地为氢,氯,氟或C 1〜C 4 - 烷基,R 3和R 4相同或不同,表示 其中Y是来自基团的二价桥连构件,Z是具有2至10个碳原子的直链或支链烃链,可以任选地含有氧桥,并且任选被1至4个丙烯酸酯或甲基丙烯酸酯基团取代, 其中R 5表示氢或甲基,R 6表示氢,可用作牙科材料的C 1 -C 6烷基或苯基。

    Process for the production of methyl methacrylate homo- or co-polymers
    40.
    发明授权
    Process for the production of methyl methacrylate homo- or co-polymers 失效
    制备甲基丙烯酸甲酯均聚物或共聚物的方法

    公开(公告)号:US4369296A

    公开(公告)日:1983-01-18

    申请号:US243877

    申请日:1981-03-16

    CPC分类号: C08F20/14

    摘要: A process for the polymerization of methyl methacrylate or mixtures thereof with up to 25%, by weight, based on total monomer, of vinyl monomers copolymerizable therewith, wherein polymerization is carried out in the presence of from 0.01 to 10%, by weight, based on total monomer, of one or more enol ethers derived from aliphatic or cycloaliphatic aldehydes or ketones.

    摘要翻译: 一种聚合甲基丙烯酸甲酯或其混合物的方法,其具有至多25重量%的基于总单体的可与其共聚的乙烯基单体,其中聚合在0.01至10重量%的基础上进行,基于 在一个或多个衍生自脂族或脂环族醛或酮的烯醇醚的总单体上。