The aromatic polyesters poly(MDP-IPC)/poly(EDP-IPC) from isophthaloyl chloride (IPC) and methyl/ethyl esters of diphenolic acid (MDP/EDP)

which were made from reactions of diphenolic acid (DPA) and methanol/ethanol

were synthesized by interfacial polycondensation with tetrabutylammonium chloride (TBAC) as phase transfer catalyst.The reaction in various solvent/water systems was investigated.It was found that a large mass of capsules were formed at the beginning of the reaction for all solvents examined

and the reaction results depended on the solvents.It is believed that the capsule shells make up of the reaction zone

and a mechanism of the interfacial polycondensation is proposed accordingly.The effect of solvents on the reaction was interpreted based on the interaction between the polymer and the solvent according to the mechanism.The aromatic polyesters with higher yield (77%) and higher intrinsic viscosity (0.66 dL/g) were obtained when dichloromethane was used as solvent.The effect of reaction conditions on the yield and intrinsic viscosity was investigated.It was found that the maximum intrinsic viscosity was reached when the molar radio of MDP to IPC was 1.1

and it was prone to gain polyesters with higher intrinsic viscosity and higher yield at higher concentration of monomers and higher reaction temperature.The thermal performance of the aromatic polyesters was studied by means of DSC and TGA.The glass transition temperature of poly(MDP-IPC) and poly(EDP-IPC) was 149.4℃ and 140.5℃

respectively.The polyesters started to decompose at 300℃ in thermal gravimetric analysis.The results showed that the two polyesters were more heat-resistant and thermostable than the diphenolic acid aromatic polyesters.