Properties of block copolymers of poly(butylene terephthalate) and polyoxytetramethylene glycol

Synthesis of polyester thermoelastoplasts, block copolymers of polyoxytetramethylene glycol and poly(butylene terephthalate) of the polyblock type, was developed and implemented in pilot industrial conditions. POTM blocks act as flexible molecular decouplings that give the copolymer elasticity, while PBT blocks form physical linkages and are responsible for the mechanical strength and hardness of the material. The composition of the reaction systems, process stage sequence, and synthesis parameters are optimized for block copolymers with a concentration of the flexible POTM block of 65-10 wt.% and a molecular weight of 1000. The structure is investigated, and the physicochemical and mechanical properties of the material obtained are determined. It was found that the concentration of flexible blocks has a determining effect on the physicochemical structure and properties of the block copolymers. For a similar to40% concentration of the flexible block, the character of the concentration curves of the physicomechanical indexes changes significantly due to phase-structural transformations in the block copolymers.