A novel multi-functional bio-based reactive diluent derived from cardanol for high bio-content UV-curable coatings application

•A novel multi-functional bio-based reactive diluent was prepared from cardanol.•Low viscosity and high reactive UV-curable reactive diluent was synthesized.•The composite UV-cured films had high bio-content and low volume shrinkage.•The bio-based diluent showed great potential to replace the traditional diluents.