Abstract: Amine-terminated polyetherurethane-urea polymers in a solvent, as for instance, isopropanol, toluene, and mixtures thereof, are chain-extended with as little as about 0.1 and up to 9 percent, by weight, based on the amine terminated polyetherurethane-urea, of a polyepoxide, such as a polyepoxide of p,p'-isopropylidenediphenol, of a phenolformaldehyde resin, epoxidized soybean oil, diglycidyl phthalate, and the like, to produce films, coatings, adhesives, and caulking having improved hydrolytic stability, and other improved physical properties.