Abstract
Abstract Composites based on copolyimides derived from alicyclic and aromatic anhydrides (ratio 90 : 10 and 85 : 15 mol %, respectively) and diaminodiphenyl ether, on the one hand, and polyacrylamide, on the other hand, were prepared. The IR spectra of the composites demonstrate formation of hydrogen bonds involving functional groups of the polymers, favoring compatibility of components in the blend. Optimum conditions for preparing composite films based on them with enhanced thermal and mechanical properties were found. The polyacrylamide constituent in the course of heat treatment of the films undergoes partial cross-linking with residual amido acid groups of the copolyimide, which enhances the heat resistance and strength of the composite films as a whole. Films with the tensile strength of 136–178 MPa and elongation of 23–17% were obtained. The composites surpass in the heat resistance the initial unmodified (co)polyimides: the alicyclic polyimide by 13–46°C and the 90: 10 and 85 : 15 copolyimides by 11 and 8°С, respectively.