Synthesis and Modifying Effect of Oligoesters with Reactive Groups Based on Epoxy Aliphatic Resin and Oligoester Dicarboxylic Acids

The purpose of this research is to study the modifying effect of oligoesters with reactive groups based on epoxy aliphatic resin and oligoesters with dicarboxylic acids with different molecular weights (adipic, sebacic, and tetradecanedioic acids). Adducts of oligoesters with terminal epoxy groups and epoxy resin (ER) were prepared. The structures of the intermediates and modifiers were characterized by FTIR, 1H NMR, 13C NMR, TGA, DMA, and SEM. The single-phase structure of the modified polymers was confirmed using the DMA, TGA, and SEM methods. It was shown that for modified polymers, a pattern of plastic deformation is observed, in contrast to the brittle destruction of the initial polymer. It has been found that elongation at break, impact strength, work of fracture, and shear strength increase throughout the studied concentration range (at 50% modifier content, elongation at break and shear strength increase by ~450% and ~150%, respectively, compared with an unmodified polymer). The results obtained demonstrate that synthesized modifiers with reactive epoxy groups can contribute to the creation of new cold-cured epoxy materials with an improved complex of properties for various industries.