Improved cardanol derived epoxy coatings

Abstract

Commercial epoxidized cardanol, from cashew nutshell liquid (CNSL), is a biobased reactant with interesting aromatic structure. Cured with two different diamines, isophorone diamine and Jeffamine T403, the synthesized materials exhibit good properties but they do not meet properties of bisphenol A diglycidyl ether (BADGE) epoxy resins. Therefore epoxidized cardanol cannot replace directly BADGE for the synthesis of epoxy resins. Three epoxy reactants, resorcinol, hBADGE and TMP, were used as reactive additives to enhance the properties of the cardanol derived materials. These epoxy networks with different ratios were characterized by thermogravimetric analysis, differential scanning calorimetry. Their hardness and gloss were measured as well as their resistance to chemical solvents.