FIELD: organic chemistry, chemical technology. SUBSTANCE: invention relates to a method of synthesis of polytetramethylene ester diesters which are used for formation of segmented copolymers with polyfunctional urethanes and complex polyesters. Indicated esters are synthesized by polymerization of tetrahydrofuran with a single of more comonomers of substituted tetrahydrofuran or alkylene oxide in polymerization reactor in the presence of solid acidic catalyst and carboxylic acid with carboxylic acid anhydride as an agent regulating molecular mass value. In the process of synthesis the decreased pressure value in reactor is adjusted in order due to evaporation and/or condensation of tetrahydrofuran to control effectively the reaction temperature value from 20 to 65 C and removing tetrahydrofuran vapors from reactor under decreased pressure that results to removal of reaction heat associated with the polymerization reaction. Invention ensures to solve the problem of removal of reaction high heat when process is converted on the commercial level. EFFECT: improved method of synthesis. 7 cl, 1 tbl
