POLYESTERS FROM HALOGENATED BISPHENOLS

Abstract

Polyesters were prepared from the interfacial polycondensation of the following bisphenols with diacid chloride of terephthalic acid or adipic acid; bisphenol-A, tetrachloro or tetrabromobisphenol-A, bisphenol-S, and tetrachloro or tetrabromo bisphenol-S. The effects of halogen substitution on the synthesis and some properties of these polyesters were investigated.Reduced specific viscosity of polyesters decreased by halogen substitution. Crystallinity and melting point of polyesters increased remarkably by halogen substitution except for poly (bisphenol-S terephthalate). The glass transition temperature of poly (bisphenol-A adipate) increased by halogen substitution. Polyesters from bisphenol-S showed thermal decomposition temperature lower and residue higher than those of polyesters from bisphenol-A. Weight loss at low temperature region and residue at high temperature region of polyesters increased by halogen substitution. Self-ignition temperature and flash point of polyesters also increased by halogen substitution. Polyesters from adipic acid were more thermally stable in air than in N2. Polyesters from bisphenol-S were more flame-retardant than those from bisphenol-A. Solubility generally decreased by halogen substitution. Young's modulus increased and the rate of hydrolysis noticeably decreased by halogen substitution for poly (bisphenol-A adipate). These results were discussed by comparing with the cases of the previously reported halogenated polyesters and polyether-esters.