Synthesis and characterization of self-crosslinking polyurethanes and their waterborne dispersions

Novel ionic waterborne polyurethane dispersions with functionality were synthesized using the acetone process as coatings for wool textile surfaces. Silane functional groups were utilized to improve the adhesion between polyurethane coating and the wool surface to increase the wrinkle recovery of wool fabrics by taking advantage of the excellent recovery of polyurethanes. The effect of the degree of chain extension, ionic content, silane content on the properties of polyurethane dispersions and their films was investigated using characterization methods including particle size analysis, viscosity, tensile tests and recovery tests. In addition, highly branched, functional polyurethane dispersions were synthesized by combining the A2+B3 polymerization with the acetone process. A polyester polyol was used as the A2 monomer and HDI based triisocyanate was used as the B3 monomer. The effect of the A:B ratio and chain terminator structure was examined. Polyurethane films obtained from highly branched waterborne dispersions by two-component or self-crosslinking chemistry were characterized by mechanical and thermal characterization methods