The invention is a two part composition comprising: A. an isocyanate functional group containing component comprising one or more polyisocyanates and one or more isocyanate functional group containing prepolymers having in its backbone the residue of one or more chains derived from polypropylene oxide, copolymers of ethylene oxide and propylene oxide or mixtures thereof wherein equivalent weight of the chains are predominantly about 780 or greater; B. an isocyanate reactive component comprising one or more polypropylene oxide, copolymers of ethylene oxide and propylene oxide or mixtures thereof having equivalent weights predominantly about 960 or greater and terminal groups which are reactive with isocyanate groups; C. one or more low molecular weight compounds having two or more isocyanate reactive groups and a molecular weight of 120 or less wherein the low molecular weight compounds are present as a residue in the isocyanate functional group containing prepolymer, as a component of the isocyanate reactive component or both; D. one or more catalysts for the reaction of isocyanate functional groups with isocyanate reactive groups wherein the catalyst may be located in the isocyanate functional group containing component or the isocyanate reactive component.