PROCESS FOR PREPARING ANTIFRICTION POLYIMIDE MATERIAL Russian patent published in 1997 - IPC

FIELD: manufacture of friction units operating under rigid conditions at temperatures higher than 300 C and at loads greater than 20 Mpa under dry friction conditions. SUBSTANCE: binder is prepared by mixing active nitrogen containing compound, excess diphenylsulfone-3,3,4,4- tetracarboxylic acid dianhydride or 3,3,4,4- tetracarboxylic acid benzophenone or 3,3,4,4- tetracarboxylic acid diphenyloxide, 4,4- diaminodiphenylmethane or 4,4-diaminodiphenyloxide and aminobenzoic acid in low-boiling aliphatic alcohols or in water or in admixture of alcohol with water (the alcohol content is at least 15% by volume of solvent). The filler is mixture of filler and modifying additive (which includes of metal oxides selected from the group consisting of Y₂O₃, Al₂O₃, TiO₂, TiO, CoO, CdO, CeO, Cr₂O₃, MgO is amount of 1-3% by weight of composition. Prior to being mixed with filler, the binder is first dried at 100-120 C for 1 hour and heated at 180-200 C for 1 hour, and molding composition is pressed at 380-390 C. EFFECT: improved properties of the antifriction material.