Synthesis of waterborne polyurethane for flexible packaging printing

The waterborne polyurethane with good adhesion to flexible packaging plastic films was synthesized using—NCO—terminated polyurethane prepolymer as a chain extender and its mechanical properties were studied. The results showed that the waterborne polyurethane with good adhesion and T-peel strength could be obtained as the molar ratio of —NCO to —OH 1. 225∶ 1 and neutralizing simultaneously with emulsifying.