Abstract: This invention relates to novel polyurethane prepolymers which consist essentially of the reaction product of a polyoxyalkylene polyol having a critical oxyethylene content and an isocyanate constituent, the reaction product having a defined level of free NCO. Particularly useful prepolymers are produced using a tolylene diisocyanate residue. The prepolymers provided have outstanding utility for rebonding polyurethane foams for applications such as, for example, carpet underlays and allow significant reductions in the adhesive level used in forming such rebonded foams and in the demolding cure times in comparison with presently used prepolymer adhesives. The prepolymers are also useful for applications in which polyurethane prepolymers are used presently such as, for example, in hydrophilic foams.