Direct polycondensation of aromatic dicarboxylic acids and bisphenols with tosyl chloride and <i>N</i>,<i>N</i>‐dimethylformamide in pyridine

Abstract

Abstract A Vilsmeier adduct derived from arylsulfonyl chlorides and DMF in pyridine was successfully used as a new condensating agent for the synthesis of aromatic polyesters by the direct polycondensation of aromatic dicarboxylic acids and bisphenols and also of hydroxybenzoic acids. Polymers of high molecular weights ( M̄ w = 78,000) with relatively narrow molecular weight distribution ( M̄ w / M̄ n ≈ 3.0) were prepared by reacting aromatic dicarboxylic acids with the adduct in pyridine, followed by addition of bisphenols. The polycondensation was significantly affected by the amount of DMF, the nature of the arylsulfonyl chlorides, the conditions of initial reaction of the acids with the adduct, and the rate of reaction with bisphenols. The process was adaptable to the direct polycondensation of hydroxybenzoic acids, affording polymers of high molecular weight (η inh = 1.73).