| abstract |
PURPOSE: To obtain the title copolymer with excellent solubility in an org. solvent, heat resistance, adhesive characteristics, strengths, etc., by reacting a specified diaminosiloxane successively with a tetracarboxylic acid dianhydride and a specified diamine component in two reaction stages. n CONSTITUTION: A siloxane-contg. polycarboxylic acid component is formed by reacting a diaminosiloxane of formula I (wherein R4 is a divalent org. group R5 is a 1-6C hydrocarbon group; m is 5-50) (e.g., formula II) with 2 molar equivalents or more of a tetracarboxylic acid dianhydride (e.g., 3,3',4,4'-biphenyl- tetracarboxylic dianhydride). Then, a polyimide copolymer suitable for an adhesive, etc., is obtd. by reacting this polycarboxylic acid component and the remaining tetracarboxylic acid dianhydride with a diamine component wherein a diamino compd. of formula III (wherein X and Y are each -O- or -C(CH 3 ) 2 -; R1-R3 are each a 1-6C hydrocarbon group; n is 0-4) [e.g., 1,4-bis(4-aminophenoxy) benzene] is a main component. n COPYRIGHT: (C)1990,JPO&Japio |