POLYMERS FROM 2,5-DIFLUOROTEREPHTHALIC ACID .1. POLYESTERS

A new synthetic route to 2,5-difluoroterephthalic acid (DFTA) was devi sed and from this several new series of polymers were prepared by poly condensation. This inaugural paper will cover polyesters while subsequ ent papers will report on keto polyethers, polyamides and other backbo nes derived from DFTA. DFTA was synthesized from 2,5-difluorotoluene, which was acylated and subsequently converted to the diacid by a sever al step oxidation process. Various polyesters were prepared by reactin g it with numerous bisphenols and diols by solution condensation to gi ve a series of difluoroterephthalate polyesters with viscosities rangi ng from 0.16 to 0.61 dl/g. Thermogravimetric analyses showed that the polyesters had thermal stabilities up to 480 degrees C in nitrogen; me lting temperatures ranged from 127 to 318 degrees C.