Thiol-ene UV-curable coatings using vegetable oil macromonomers

Allyl, acrylate, and vinyl ether derivatives of castor oil were synthesized and blended with multifunctional thiols for evaluation as thiol-ene ultraviolet (UV) curable systems. The UV cured films were characterized and evaluated via ASTM tests, gel content, and dynamic mechanical analysis (DMA) as a function of time. Fourier transform infrared spectroscopy and DMA studies established that property advancement resulted from auto-oxidation, continued thiol-ene polymerization, or a combination of both mechanisms.