Harnessing Tannic Acid as a Cross‐linker in Betel Nut Fiber Reinforced Modified Epoxidized Soybean Oil Based Composites

ABSTRACT

Agro‐wastes generated during betel nut harvesting can be efficiently valorized as reinforcing materials in the development of natural fiber‐reinforced polymer composites, in accordance with waste‐to‐wealth concept. In this study, biocomposites were fabricated using waste betel nut husk fiber (BNF) as the reinforcing material, maleinated acrylated epoxidized soybean oil (MAESO resin) as the matrix, itaconic acid—glycidyl methacrylate adduct as the reactive diluent and tannic acid (TA) as cross‐linking agent. BNF was subjected to alkali treatment before using it as a reinforcement. The composites were prepared through compression molding method by keeping the resin‐to‐filler ratio as 70:30 and varying the concentration of cross‐linker (3, 5, and 7 wt %). The prepared resin and diluent were characterized using Fourier transform infrared spectroscopy (FTIR). A comparative study of prepared composites with varying cross‐linker percentage was conducted to evaluate their overall properties. Density functional theory (DFT) calculations were carried out for the reactants and the probable cross‐linking reaction and the findings were confirmed using FTIR spectroscopy. Mechanical properties, thermal stability, morphology, and wettability of the composites were examined. Among all the samples, the composite with 5 wt % TA exhibited the highest improvement in properties.