Carborane-containing tetraketodianhydrides, their dimers and polyimides on their base

The new dianhydride of 1,7-bis[4-[4[(3,4-dicarboxybenzoyl)phenoxy]benzoy] carborane fusible at 421-423 K and its nonfusible dimer have been synthesized. New nonfusible carborane-containing dimers of tetraketodianhydrides were obtained as a result of acylation of diphenyl and fluorine. Polymides soluble in amide solvents and concentrated sulfuric acid and resistant towards the thermooxidative degradation were synthesized by low-temperature (353 K) and high-temperature (453 K) polycondensation in one stage with the 80-90 % yield. Polymide moldings were prepared from blends of powders of tetraketodianhydrides dimers and diaminodiphenyl ester by reactive formation method