界面缩聚法制备间苯二甲酰双酚酸酯聚芳酯

以四丁基氯化铵为相转移催化剂,双酚酸甲酯或双酚酸乙酯与间苯二甲酰氯界面缩聚,合成得到了侧链含酯基的聚芳酯.在吡啶、三乙胺、碳酸氢钠、氢氧化钠中选择合适的催化剂,既可以发生聚合反应又不会使双酚酸酯的酯基发生水解.聚合反应在7种溶剂中进行,通过探讨聚合反应机理以解释溶剂对聚合反应产率以及聚合物特性黏数的影响.以二氯甲烷为溶剂,在优化的聚合条件下较高产率地得到了高特性黏数的聚合物.DSC及TGA分析表明,间苯二甲酰双酚酸酯类聚芳酯具有比间苯二甲酰双酚酸好的热稳定性,热分解温度可从200℃提高到300℃.

SYNTHESIS OF AROMATIC POLYESTERS FROM ESTERS OF DIPHENOLIC ACID AND ISOPHTHALOYL CHLORIDE BY INTERFACIAL POLYCONDENSATION

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.