Synthesis and properties of quick-drying UV-curable hyperbranched waterborne polyurethane coating

Ultraviolet light (UV)-curable hyperbranched waterborne polyurethane (UVHWPU) resins were synthesized using polypropylene glycol (PPG)-1000, dimethylol propionic acid (DMPA), trimethylol propane (TMP), isophorone diisocyanate (IPDI) as core moiety, and 2-hydroxyethyl methacrylate (HEMA) as capping agent. The preparation methods of the UVHWPU resins were studied and an optimum recipe was given by selecting the proper dosage of DMPA, PPG-1000 and TMP. The structure of hyperbranched resins was characterized by C13-NMR spectra and Fourier transform infrared (FTIR) spectroscopy. The type and dosage of photoinitiator were determined, and the properties of UVHWPU coating with excellent performance were examined.