Isophthalic Acid → Bisphenol A

Participants

Reaction Conditions

Reaction Steps

An equimolar mixture of 2,2-bis(4-acetoxyphenyl)propane (Bisphenol A diacetate) and isophthalic acid is heated gradualy to 290° C. in a stirred vessel under gradually increasing vacuum to remove the acetic acid which is liberated. When the melt viscosity of the condensate reaches a level such that stirring becomes difficult the melt is drained from the reaction vessel and crystallized. The crystallized polymer is subjected to solid state polymerization under vacuum at 280° C. until the inherent viscosity reaches 0.65 dl/g (in 40/60 by weight tetrachloroethane/phenol solution at 25° C.). The polymer is then extruded at 350° C. and pelletized. The polymer has an inherent viscosity of 0.62 and a carboxylic acid content of 40 microequivalents per gram (μeq./g), determined by potentiometric titration of a solution of the polymer in a 2,6-dimethylphenol/chloroform/ethanol mixture with an ethanolic solution of potassium hydroxide.

Provenance & Evidence