Research on Synthesis Technology of Polyester Diol Using Vacuum Melting Method

Abstract

Using adipic acid, ethylene glycol and diethylene glycol as the main raw material, the polyester diol was prepared by vacuum melting method. The effects of the dosage of catalyst, the stuff molar ratio of diol and diacid, reaction temperature of the esterification reaction and other factors on the synthesis process of polyester diol were investigated. The optimal conditions of the polyester diol synthesis by vacuum melting method were determined as follows: the stuff molar ratio of diol and diacid 1.10:1, the dosage of catalyst 0.20‰ (the mass fraction of total amount of dicarboxylic acid and diols), the esterification reaction temperature 230 oC. Under such conditions, the esterification reaction time is 5.5 h to get qualified polyester polyol. Additionally, the structure characteristics of polyester glycol were studied by infrared spectrometer (FTIR) and thermogravimetric analyzer (TGA).