Commercial epoxidized cardanol, from cashew nut shell liquid (CNSL), is a biobased epoxide reactant with interesting aromatic structure. Epoxidized cardanol was thoroughly analyzed using 1H and 13C NMR, size exclusion chromatography, and titration in order to determine the structure. This epoxidized cardanol was reacted with isophorone diamine and Jeffamine D400 diamine in order to synthesize epoxy networks. These epoxy networks, formulated in stoichiometry ratio, were characterized by differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical analysis analyses and were compared to bisphenol A diglycidyl ether (DGEBA) network. Cardanol-based epoxy materials exhibit interesting mechanical and thermal properties for coatings.
Practical application: The reactant described in this contribution, i.e. epoxidized cardanol from CNSL, provides biobased aromatic building blocks for further epoxy resin syntheses by reaction with amine hardeners. The obtained epoxy networks are partially biobased and may be applied as binders and coatings.