Bio-based coating resins derived from cardanol using carbocationic polymerization and their evaluation as one-component alkyd-type coatings

A novel biobased monomer, cardanol ethyl vinyl ether (CEVE) and its autooxidatively curable linear homopolymer and copolymers were synthesized using carbocationic polymerization. Cardanol, a component of cashew nut-shell liquid has a unique phenolic structure with an unsaturated fatty chain. The polymers were cured oxidatively at both ambient and elevated temperatures (120 and 150 °C) resulting in crosslinked networks with better physical and thermomechanical properties than two commercial reference alkyds. Variations in the glass transition temperature (T g ) (5.6 to 26 °C), crosslink density (3.92 to 16.6 mol/cm 3 ), tensile properties (12.2 to 26.6 MPa), and hardness (15 to 40 Sec.) were achieved by changing the copolymer composition from poly(CEVE) to poly(CEVE- co -CHVE)-50/50. These results clearly show the potential of these cardanol-based polymers for use as surface coatings. The synthesis of monomer and linear polymers based on cardanol derivable from cashew nut shell liquid, and study of their autoxidatively-cured networks are presented. • Novel vinyl ether monomer was synthesized from biobased phenol cardanol. • Cardanol-based polymers were produced via carbocationic polymerization. • Cardanol-based polymers can undergo autoxidation through alkyl chain unsaturation. • Coatings cured via autoxidation show properties better than those from alkyd resins.