US Patent 7342068 Aqueous polyurethane dispersion and method for making and using same

Aqueous polyurethane dispersions comprising polyurethane polymer and methods for making and using same are disclosed herein. In one aspect of the present invention, aqueous polyurethane dispersions, comprising a polyurethane polymer having a weight average molecular weight ranging from 20,000 to 80,000, are prepared by controlling the weight average molecular weight of the polymer by reacting the isocyanate terminated prepolymer with at least one chain terminating agent; and/or maintaining a N/COOH molar ratio of amine in the neutralizing agent to acid functional group in the isocyanate reactive compound to from about 0.5:1 to about 1:1.