The preparation of hydrogel-like polyurethane using the graft polymerization of N,N-dimethylaminoethyl methacrylate and acrylic acid

The surface of polyurethane (PU) was modified by the graft polymerization of N,N-dimethylaminoethyl methacrylate (DAMA) and acrylic acid (AA) to enhance its water compatibility. Portions of poly(DAMA) and poly(AA) could be ionized by mutual acid–base neutralization and could notably improve the surface hydrophilicity of PU. The water contact angle, water absorption, and water vapor permeation test results jointly demonstrate the increase in water compatibility resulting from the inclusion of poly(DAMA) and poly(AA) in PU. The melting and glass transition temperatures of PU were not significantly influenced by the grafting of poly(DAMA) and poly(AA) onto PU. Small portions of the grafted poly(DAMA) and poly(AA) were involved in the cross-linking of PU, which sharply increased the shape recovery and the breaking tensile stress while maintaining high shape retention and breaking tensile strain.