This paper includes a series of experiments conducted in order to develop a laboratory method for producing 3,3', 4,4'-benzophenonetetracarboxylic dianhydride and selection of the optimum conditions, allowing to obtain the greatest yield. 3,3', 4,4'-benzophenonetetracarboxylic dianhydride is used for the preparation of polyimides with high thermal stability, chemical resistance as well as high strength and high Young's modulus. Benzophenonetetracarboxylic dianhydride was prepared by multistep route: Friedel-Crafts alkylation of o-xylene to obtain 3,3', 4,4'-tetramethyl benzophenone followed by liquid phase oxidation to benzophenonetetracarboxylic acid and dehydration.

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This article describes the study of producing composites based on polyimide matrices containing nanostructured boron carbide as reinforcement particles. To improve the adhesion between ceramic particles and matrix material the boron carbide was pre-modified. The composites were produced using high temperature in situ polymerization method, with aromatic tetracarboxylic dianhydrides and aromatic diamines used as monomers. In particular, 4,4'-isopropylidene diphthalic anhydride, 4,4'-(p-phenylenedioxi)bis[phthalic anhydride], 4,4'-oxydianiline, 4-[4-(4-aminophenoxy)phenoxy]aniline were used as monomers, while the filler content was 20 to 60 wt. %. Mechanical properties, imidization degree and thermal resistance of the composites produced were studied as well.

In this work, polymeric sorbents based on polyimides with crown ethers for extraction of metal ions from aqueous environment were determined and investigated. The sorbents were made using various monomers (aromatic acid dianhydrides) and crown ethers. Samples of polymeric sorbents showed high values of the extraction extent of metals ions such as cobalt and cesium, and also good temperature resistance.

A method of producing composite materials based on ultra high molecular weight polyethylene (UHMWPE) and metal oxides, such as rare-earth elements oxides (REE oxides), including gadolinium, dysprosium and tungsten oxides, was developed in this study. The surface of oxide fillers was modified using organosilicon coupling dressing agents in the acid catalysis environment. The modification allows to produce compositions containing significant amount of filler (over 30%). The effect of introduction of rare earth oxides into the matrix of ultrahigh molecular polymer up to 40% by weight on thermal and oxidative degradation was studied.