Partly cured polyimide prepolymer - by heating aromatic polycarboxylic acid and aromatic amino cpd in dipolar aprotic solvent

摘要

Partly cured polyimide prepolymer is prepd. by heating either (a) a mixt. of an aromatic acid monomer and an aromatic amino cpd., or (b) an aromatic aminocarboxyl cpd. at a temp. of =200 degrees C in the presence of a dipolar aprotic solvent with a b.p. of =200 degrees C and a m.p. of =0 degree C until the weight loss of the pdt. is 2 - 15%. The aromatic acid monomer consists of (1) an aromatic tetracarboxylic acid, or its dianhydride or di- or tetraesters, in which the carboxyl gps. are grouped in pairs, and each pair of carboxylic acids is bonded to adjacent C atoms or situated in the peri position relative to each other, or (2) an aromatic tricarboxylic acid, or its anhydirde, or mono-, di- or triesters, in which 2 of the carboxyl gps. are in ortho or peri relation.