Interpenetrated hybrid thiol-ene/epoxy UV-cured network with enhanced impact resistance

•Epoxy toughening.•Thiol-ene photopolymerization.•hybrid epoxy/thiol-ene.•Impact Resistance behaviour. Interpenetrated hybrid thiol-ene/epoxy network were obtained via UV-induced polymerization. By combining the network structure derived from epoxy curing with that of thiol-ene system we could expect an important toughening effect due to the presence of the polysulfide moieties. It is proposed the use of a penta-allylic triamine curing agent which can react with multifunctional thiols to produce polysulfides in situ, and at the same time has the ability to initiate the anionic polymerization of an epoxy resin. The higher the concentration of polysulfides in the resultant polymer, the better the toughness achieved.