Solvent-Free, UV-Curable Cellulosic Adhesives Engineered via a Supramolecular Eutectic Platform for Robust Adhesion.

Abstract

Cellulose-based adhesives offer sustainable alternatives to petroleum-derived products but face bottlenecks regarding organic solvent reliance, slow curing efficiency, and moisture sensitivity. Here, a solvent-free, UV-curable cellulosic adhesive (UCA) is developed via a supramolecular-covalent hybrid strategy. Utilizing a cellulose acetate butyrate/thymol eutectic platform, multi-component functionalization with silane, photoactive acrylic moieties, and fluorinated monomer yields a transparent, photocurable prepolymer. The cured UCA exhibits a lap-shear strength of 6.73 MPa on PMMA, high optical transparency, and broad temperature tolerance. Synergistic surface hydrophobicity, interfacial coupling, and dense photocrosslinking impart strong water resistance, retaining 5.86 MPa shear strength after 3-day water immersion and 5.12 MPa after 1 h in 100°C boiling water. The adhesive also withstands strong acids, bases, and organic solvents. This work provides a practical route for engineering high-performance bio-based adhesives.