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.