Preparation of UV curable waterborne polyurethane and its application in coatings

摘要

Waterborne UV curable polyurethane emulision contAlNing C=C bond was prepared with selfemulsification. 3% water soluble photoinitiator was added to the polyurethane emulision, and polyurethane films was prepared by ultraviolet irradiation. The structure of the polyurethane emulision and films were confirmed by means of Fourier transform infrared spectroscopy(FTIR), transmission electron microscopy(TEM) and thermogravimetric analysis. FTIR test result shows that cross linking and solidification reaction of C=C double bond happened after UV irradiation. When C=C content increases, the particle size of polyurethane emulision increases, crosslinking degree of films increases, water resistance and heat resistance have both been improved. When C=C content is 8.51%, gel content is more than 90% and the lowest water absorption can be 12.5%.