Biobased Epoxy Synthesized from a Vanillin Derivative and Its Reinforcement Using Lignin-Containing Cellulose Nanofibrils

A simple and rapid synthesis of biobased epoxy resin derived from vanillyl alcohol was performed, and its chemical structure was confirmed by FTIR and H-1 and C-13 NMR spectroscopies. Vanillin-based epoxy resin (VE) was further reinforced by lignin-containing cellulose nanofibrils (LCNFs) with different weight ratios. Characteristics of the resin and the nanocomposites, including the curing process, chemical structure, morphology, mechanical performance, thermo-mechanical properties, and thermal degradation behavior, were studied. A significant improvement in the mechanical performance of the nanocomposites was achieved with a low level of nanofibril addition. Tensile strength and toughness increased by 81% and 185%, respectively, when 1 wt % of LCNFs were used. The nanocomposite also showed an increase in thermo-mechanical properties as measured by dynamic mechanical analysis (DMA) and increased resistance to thermal degradation as shown by higher onset temperature and final char value in thermogravimetric analysis (TGA). This study showcased a promising approach to make environmentaly friendly sustainable biobased epoxy products with superior performance.