Binders Based on Mixtures of Epoxy Polymers and Thermoelastoplasts. Part 3. Adhesive Properties of Epoxy Polymers Modified with Polybutadieneterephtalate–Polytetramethyleneoxide Block Copolymers

Abstract: The effect of thermoelastoplasts, which are block copolymers based on polybutylene terephthalate and polytetramethylene oxide with different ratios of rigid and elastic blocks, on the adhesive properties of epoxy polymers has been studied. It has been established that the dependences of the adhesive strength in shear and peel-off on the amount of introduced block copolymer are of an extreme nature and the positions of the maxima and their intensity depend on the ratio of the rigid and elastic blocks in the thermoelastoplast. It is shown that the effect of increasing the adhesive strength is more pronounced at elevated test temperatures. It has been established that modification with thermoelastoplast makes it possible to increase the deformability and work of destruction of epoxy composites in a wide temperature range from 150 to 423 K. A comparative study of the modifying effect of thermoelastoplasts, oligosulfone, and oligobutadiene rubber with terminal carboxyl groups on the adhesion and deformation-strength properties of epoxy composites has been carried out.