As difunctional compounds containing an ionic bond in the molecule, divalent metal salts (I) of mono(hydroxyethyl) phthalate were prepared in high purity and high yield. Mg and Ca were selected as divalent metal. Metal-containing polyurethanes containing ionic links in the main chain were synthesized by the polyaddition reaction of I or, I–glycols with diisocyanates. The polyurethane obtained were glassy materials or white powders, depending on the species of diisocyanates and glycols. Close agreement between observed and calculated values of metal content of the polyurethanes were obtained. The viscosities (in dimethyl-formamide) of the polyurethanes decreased markedly with increasing of metal content. Moreover, the decomposition temperatures were lowered by introduction of metals into the polyurethanes. However, the decomposition rates of metal-containing polyurethanes were lower than those of polyurethanes not containing metal.
