Synthesis of aromatic polyesters derived from bisphenol‐A and bis(hydroxyphenyl)butane with diacyl chloride monomers

Abstract A series of aromatic polyesters were prepared by the reaction of bisphenol‐A and bis(hydroxyphenyl)butane with diacyl chloride monomers by phase transfer interfacial polycondensation in order to improve the processability of the bisphenol A‐based polyarylate. The microstructure, molecular weight, crystallinity, solubility, thermal properties, mechanical properties, and optical properties of the prepared copolyesters were investigated. Inherent viscosities of the copolyesters are in the range of 0.14–0.53 dl g −1 , and their average molecular weights are 7362–44,413 g mol −1 , respectively. The feed compositions and copolymer compositions were nearly identical. The results show that with the increase in the content of side ethyl units, the copolyester gradually transforms into an amorphous structure, which is also verified by the improvement in dissolution properties. When the copolyester backbone was introduced into the side ethyl units, the thermal decomposition temperature was less affected and varied in the range of about 10°C, while the value of glass transition temperature reduced from 196.5°C to 165.1°C. The mechanical properties of the polymers are similar to those of the industrial commodity U‐100. In addition, the copolyester films have good optical properties, and the transmittance reached the maximum value of 98.41% when the content of bis(hydroxyphenyl)‐butane was 10%.