Synthesis of eugenol-based multifunctional monomers via a thiol–ene reaction and preparation of UV curable resins together with soybean oil derivatives

Two kinds of UV-curable monomers (EM2G and EM3G) were synthesized from eugenol via a thiol–ene reaction. Their chemical structures were confirmed by FT-IR, 1H-NMR and 13C-NMR before they were employed to copolymerize with acrylated epoxidized soybean oil (AESO). Bio-based UV curable resins were prepared and their thermal and mechanical properties were investigated by tensile testing and dynamic mechanical analysis (DMA). Their coating properties on tinplate were also studied. The results showed that the tensile strength, tensile modulus and glass transition temperatures of the cured AESO were significantly improved after the introduction of eugenol-based monomers. In addition, the UV-cured resins could be well coated on the surface of tinplate and good coating properties, such as hardness, flexibility, adhesion, solvent resistance and water absorption were demonstrated.