NanoLiBRe · Functionalizing Tailored Nano Lignin for Recyclable Bio-based Resins

An increasing number of countries are promoting the development of bio-based materials as a sustainable strategy to mitigate climate change and reduce dependence on fossil resources. Simultaneously, concerns about health risks and formaldehyde emissions from conventional wood resins have intensified efforts to develop bio-based adhesives as safer, sustainable, and recyclable alternatives. This project aims to advance kraft lignin through innovative modification strategies to produce novel, functionalized nano-lignin adhesives with recyclability and biodegradability. The approach involves lignin fractionation using green methods to reduce structural heterogeneity, followed by size reduction to the nanoscale to enhance lignin homogeneity. To improve lignin nano particles (LNPs) preparation yield and stability, a novel bio-based capping agent will be applied to prevent undesired LNPs re-condensation, following reversible bonding chemistry principles. Purified LNPs will undergo self- and bio-based crosslinking, oxidative modification, and amino acid functionalization to establish covalent bonds within the LNPs structure. The project will pioneer the use of bio-capping agent for LNPs preparation and their functionalization by amino acids, as fully bio-derived crosslinkers, to create high-performance, biodegradable thermosetting adhesives capable of replacing formaldehyde-based resins in wood composites. Additionally, it will systematically investigate the influence of lignin’s molecular heterogeneity, size distribution, bio-capping agent efficiency, oxidative modification, and bio-crosslinking efficiency on the final adhesive performance. Adhesion performance will be evaluated using renewable materials such as wood veneers in the fabrication of bio-based composite. Ultimately, this project will introduce new methods enabling the practical use of green, fully bio-derived adhesives in bio-composite production providing a viable alternative to conventional synthetic resins.