Sustainable Replacement of Phenol for Synthesis of Phenol-Free Phenolic Resin from Sugar Waste

Phenolic resins are extensively utilized in various industries, but their production using non-renewable and petroleum-based phenol and formaldehyde raise concerns over cost and adverse effects on human health and the environment. Hence, the development of alternative phenol sources is imperative to achieve sustainable production and promote environmental sustainability in the field of polymer chemistry. This study aims to investigate the feasibility of synthesizing lignin-based phenolic resin, using fractionated acetone-treated lignin extracted from sugar waste, as a substitute for toxic and non-renewable phenols. Specifically, the acetone treatment is used for fractionating lignin to select the optimal components for phenolic resin synthesis. Experimental results indicate that the lignin exhibits improved solubility in a 60% acetone solution, leading to a simplified configuration and enhanced bonding mode. The resulting phenolic resin synthesized using lignin as a phenol source demonstrates superior bonding strength (1.57 MPa) compared to industrial phenolic resins (1.14 MPa). Furthermore, the resin exhibits a negligible amount of released free phenols (0.05%), which significantly mitigates environmental concerns. To conclude, this study presents a novel approach to develop a lignin-based phenolic resin using sugar byproduct as a feasible substitute for phenols, addressing the limitations associated with their production. These findings offer promising prospects for sustainable production practices in polymer chemistry.