A process for making a curable resin composition comprising the steps of: (1) reacting a) an isocyanate; and b) a polyol mixture with a bimodal distribution of i) a first polyol mixture comprising polyols having an average equivalent weight of from 50 to 400; and ii) a second polyol mixture comprising polyols having an average equivalent weight of from 1000 to 5000 to form a urethane prepolymer; and (2) adding a capping agent to the urethane prepolymer to form the curable resin composition.