Synthesis of cardanol-based photo-active SET-LRP initiator and its application to preparation of UV-cured resin

A benzophenone-containing SET-LRP initiator based on renewable and abundant cardanol was synthesised in 71 % yield using the selective etherification reaction. Next, methyl methacrylate (MMA) as a monomer was polymerised under SET-LRP conditions using the newly prepared initiator to prepare cardanol-end poly(methyl methacrylate) (PMMA). The kinetic results of the polymerisation indicated that the reaction was controllable when the monomer conversion was lower than approximately 50 %, and the molecular masses of PMMA measured by GPC were higher than the theoretical values while the monomer conversion was more than 50 %. In addition, most of the carbon-carbon double bonds of the side hydrocarbon chain of the end-cardanol group in the PMMA were kept intact from ¹H NMR spectrum characterisation. Accordingly, when the cardanol-end PMMA together with a tertiary amine-containing cardanol derivative was irradiated by UV light, the corresponding UV-cured resin was obtained. The chemical resistance and hardness of the UV-cured film were enhanced with the increasing irradiation time.