Production of arylene sulfide polymers

Abstract

A method by which arylene sulfide polymers are produced by admixing p-dihalobenzene, optionally together with a polyhalo aromatic compound having more than two halogen substituents per molecule, an alkali metal sulfide, an alkali metal carboxylate or a lithium halide, an alkali metal hydroxide, and N-methyl-2-pyrrolidone at polymerization conditions with the addition of carbon dioxide either during the polymerization or upon completion of the polymerization but prior to removal of N-methyl-2-pyrrolidone by distillation at elevated temperatures thereby producing a polymer, after washing, of lower melt flow than is obtained without the addition of carbon dioxide. In an embodiment of the invention the use of carbon dioxide makes unnecessary the use of vacuum distillation in recovering N-methyl-2-pyrrolidone from the reaction effluent and also makes possible improved recovery of N-methyl-2-pyrrolidone.

Dependencies are inferred from the claim text.