申请人:Dow Corning Corporation
公开号:US05473041A1
公开(公告)日:1995-12-05
There is disclosed an organopolysiloxane having bifunctional biphenyl groups of the formula I ##STR1## wherein Q is selected from the group consisting of a nitro group, a substituted amino group and an unsubstituted amino group, Z is an organopolysiloxane group represented by the formula II ##STR2## in which R.sup.1 is a divalent organic group having at least 2 carbon atoms, R.sup.2 through R.sup.6 are the same or different monovalent organic groups, n is an integer having a value of at least 1 and m is 0 or 1. The above organopolysiloxane may be reacted with an aromatic tetracarboxylic acid dianhydride and, optionally, with an aromatic diamine to obtain a polyamide acid, which may then be subjected to a thermal imidization step to provide a polyimide having repeating units shown by the formulas VI and VII ##STR3## wherein A.sup.1 is a tetravalent aromatic group, A.sup.3 is a divalent aromatic group and A.sup.2 is a divalent organic group which contains a siloxane residue and wherein the molar ratio of repeating unit VI to repeating unit VII in the range 100:0 to 1:99.
本发明公开了一种具有式I的双功能联苯基的有机聚硅氧烷:##STR1## 其中Q选自一硝基团、一个取代氨基团和一个未取代氨基团的群,Z是由式II表示的有机聚硅氧烷基团:##STR2## 其中R.sup.1是至少具有2个碳原子的二价有机基团,R.sup.2至R.sup.6是相同或不同的一价有机基团,n是至少为1的整数,m为0或1。上述有机聚硅氧烷可以与芳香族四羧酸二酐反应,并且可以选择性地与芳香族二胺反应,以获得聚酰胺酸。然后可以对聚酰胺酸进行热咪唑化步骤,以提供具有重复单元VI和VII的聚酰亚胺:##STR3## 其中A.sup.1是四价芳香族基,A.sup.3是二价芳香族基,A.sup.2是含有硅氧烷残基的二价有机基团,其中重复单元VI与重复单元VII的摩尔比在100:0至1:99的范围内。