Abstract: Polyphenylene sulfides are synthesized by refluxing a mixture of an aromatic sulfide and an aromatic dibromide such as m-benzenedithiol and m-dibromobenzene in a basic medium of potassium carbonate in dimethylformamide or dimethylacetamide. The products obtained are slightly off-white with relatively low melting ranges and have inherent viscosities in the 0.2 to 0.4 dl/g range in hexamethylphosphoric triamide. Similar polyphenylene sulfides containing pendant cyano groups along the polymer chains were obtained using 5 mole-% of either 2,4-dichlorobenzonitrile or 3,5-dichlorobenzonitrile as a reaction constituent. The products were similar to the pure polyphenylene sulfides except that they showed lower melting ranges and gave insoluble products when heated alone or in the presence of zinc chloride.