A brief review of the conducted research by the authors of this report on the development of arylalicyclic copolyimides based on alicyclic dianhydride, aromatic dianhydrides of benzophenone- and diphenyloxidetetracarboxylic acids with 4,4'-diaminodiphenyl oxide at various ratios of alicyclic and aromatic dianhydrides, as well as various compositions based on these copolymers with low- or other high-molecular compounds that enhance the characteristics of the polymer matrix. Composite films were formed from solutions of the obtained polymer mixtures, and their properties were studied. It was noted that at optimal ratio of components, the films have improved thermal and strength properties, etc., exceeding the analogous properties of the initial arylalicyclic copolymer, while the elasticity has acceptable values for such material. The best characteristics had the composite films formed from a ternary composition of copolyimide-polyethylene glycol-alkylated montmorillonite. Metal-containing composite films, along with higher thermal stability compared to unmodified copolyimide, were resistant to aggressive reagents, lower values of specific volume and surface resistance, higher viscosity values, and different colors depending on the nature of the salt. By introducing a silicon-containing compound into the copolyimide solution, the new polymer systems have been obtained, and the porous films could be formed.