Study on the synthesis of crosslinking waterborne polyurethane-acrylic composite emulsion and the film properties

A novel emulsion of crosslinked waterborne polyurethane-acrylic copolymers (PUA) was successfully synthesized by in-situ emulsion copolymerization method in this paper, using IPDI, PCDL-1000, BDO, DMPA, GMA as the main raw material. The effects of the content of crosslinking agent on the properties of composite emulsion and its films was studied systematically. FT-IR, TGA, XRD, SEM were employed to investigate the structures and properties of the composite latex and their polymers. The results showed that moderate crosslinking could contribute to improving the water resistance and mechanical properties of materials. When n(GMA)/n(DMPA)=0.1-0.2, the WPUA latex has a stable performance as well as an excellent thermal stability and water resistance of the polymer, the bibulous rate of the crosslinked films was low to 5.4%. The tensile strength of the crosslinked WPUA films achieved 28.9 MPa, increased by 173% of the uncrosslinked one.