Synthesis of polyarylate by one-pot reaction using reactive distillation condensation polymerization starting from terephthalic/isophthalic acids, bisphenol A, and acetic anhydride mixture systems

We invented a new and effective process for the preparation of polyarylate using reactive distillation condensation polymerization. The concept of the reactive condensation polymerization came from the application of reactive distillation, which is usually used for the synthesis of eater compounds o f low molecular weight, to the condensation polymerization. Applying this n ew method to the one-pot reaction for the synthesis of polyarylate starting from terephthalic/isophthalic acids, bisphenol A, and acetic anhydride in the presence of a high boiling solvent such as biphenyl/diphenyl ether, we developed a simple process for manufacturing polyarylate. This one-pot reac tion for the synthesis of polyarylate consists of 4 unit processes that inc lude acetylation of bisphenol A with acetic anhydride, condensation polymer ization of bisphenol A diacetate with terephthalic/isophthalic acids by rem oving acetic acid in the presence of biphenyl/diphenyl ether, further conde nsation polymerization of the prepolymer by removal of acetic acid with bip henyl/diphenyl ether vapor, while feeding the biphenyl/diphenyl ether mixed solvent, and finally, evaporation of the biphenyl/diphenyl. ether from the molten polyarylate using a self-cleaning type twin screw extruder. The pol yarylate obtained from this one-pot synthesis showed goad mechanical proper ties which are comparable to those of the commercially available polyarylat e.