Fecha de publicación: 13/01/2025 Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE ABSTRACT
Epoxy resins is widely applied in various industrial production. Lignin exhibits enormous potential as an alternate for health-risk compound, bisphenol A, in the preparation of epoxy resin adhesives. However, the complicated structures and low reactivity limit the further utilization of lignin. In this study, a green deep eutectic solvent (DES) was utilized to enhance the phenolic hydroxyl content of hard wood organic lignin, from 3.63 to 5.63 mmol/g, to promote the reactivity of lignin during the preparation process of epoxy resin adhesives. Enabling by the DES induced lignin activation, the prepared lignin-based epoxy resin exhibited excellent epoxy-value (0.41 mol/100 g) and the as-prepared adhesives possessed remarkable mechanical properties (tensile stress up to 50.86 MPa). Even after exposure to extreme conditions (freezing or soaking for 48 h), the adhesives maintained over 70% mechanical strength. This work contributes to the broader effort towards sustainable lignin-based adhesives in industrial applications.