Plant oil-based epoxy resins from fatty diamines and epoxidized vegetable oil

Herein, the synthesis of vegetable oil-derived diamines by thiol-ene coupling (TEC) using cysteamine hydrochloride is reported. Despite the amine group in cysteamine that is unfavorable to TEC, fatty allylamide (FM-A) provides an aminated fatty amide (AFA). Due to other diamides, the influence of the fatty structure on the TEC reactivity was demonstrated. The structures were characterized using FFIR and H-1 NMR spectroscopies, and the crosslinking of epoxidized linseed oil (ELO) with AFA was investigated using differential scanning calorimetly (DSC) and dynamic rheometry. The thermomechanical behavior of the plant oil-based thermoset was also characterized and compared to a commercial diamine based on a fatty dimer structure and a branched polyamine prepared from grapeseed oil. Finally, the beneficial effect of oxidation of the epoxy resin on the thermomechanical properties is highlighted. (C) 2015 Elsevier Ltd. All rights reserved.