abstract |
Novel thermoplastic polyester polyurethanes are disclosed which are obtained by reacting a polyester diol, a difunctional extender, a methylenebis(phenyl isocyanate), and from about 0.0025 mole to about 0.03 mole per equivalent of isocyanate of a monocarbodiimide product derived from a methylenebis(phenyl isocyanate) or the corresponding uretidinedioneimine adduct thereof with said latter methylenebis(phenyl isocyanate). The polyester polyurethanes are characterized by a combination of thermoplasticity, extremely good hydrolytic stability which cannot be diminished by solvent action, good physical properties, particularly tensile strength and elongation, and enhanced clarity of molded articles. |