Utilization of catecholic functionality in natural safrole and eugenol to synthesize mussel-inspired polymers

Advancements and Perspectives toward Lignin Valorization via O-Demethylation

Lignin represents the largest aromatic carbon resource in plants, holding significant promise as a renewable feedstock for bioaromatics and other cyclic hydrocarbons in the context of the circular bioeconomy. However, the methoxy groups of aryl methyl ethers, abundantly found in technical lignins and lignin-derived chemicals, limit their pertinent chemical reactivity and broader applicability. Unlocking the phenolic hydroxyl functionality through O-demethylation (ODM) has emerged as a valuable approach to mitigate this need and enables further applications. In this review, we provide a comprehensive summary of the progress in the valorization of technical lignin and lignin-derived chemicals via ODM, both catalytic and non-catalytic reactions. Furthermore, a detailed analysis of the properties and potential applications of the O-demethylated products is presented, accompanied by a systematic overview of available ODM reactions. This review primarily focuses on enhancing the phenolic hydroxyl content in lignin-derived species through ODM, showcasing its potential in the catalytic funneling of lignin and value-added applications. A comprehensive synopsis and future outlook are included in the concluding section of this review.

Preparation mechanism and performance evaluation of deep eutectic solvent-lignin/ZnO composites by one-pot

Lignin, as the aromatic polymer in the world, has attracted more attention because of rich functional groups. In this study, lignin/ZnO composites was prepared by a simple one-pot method rely on urea and ZnCl₂-deep eutectic solvent (U/ZnCl₂-DES) as solvent and raw material. Through molecular dynamics simulation, the interaction mechanism between lignin functional groups and DES was clarified, and it was blended with waterborne polyurethane (WPU) to form a film, while the feasibility of its application in ultraviolet shielding was evaluated. The results showed that lignin /ZnO composites with excellent ultraviolet shielding properties were successfully prepared. Compared with lignosulfonate (SL), enzymatic hydrolysis lignin (EHL) was easier to combine with ZnO, which was benefit to prepare lignin/ZnO composites. When the addition of EHL/ZnO-N_12.5 complex was 1.5 %, the WPU film prepared has good mechanical properties (elongation at break was 25.53 %, tensile strength was 1422 kPa), good light transmission and ultraviolet shielding.

Eugenol, a Promising Building Block for Biobased Polymers with Cutting-Edge Properties

Biobased materials, derived from biomass building blocks, are essential in the pursuit of sustainable materials. Eugenol, a natural phenol obtained from clove oil, but also from lignin depolymerization, possesses a chemical structure that allows its easy modification to obtain a broad and versatile platform of biobased monomers. In this Perspective, an overview of the variety of reactions that have been executed on the allylic double bond, phenol hydroxyl group, aromatic ring, and methoxy group is given, focusing our attention on those to obtain monomers suitable for different polymerization reactions. Furthermore, possible applications and perspectives on the eugenol-derived materials are provided.