Hydrogen bond reconstruction strategy for eutectic solvents that realizes room-temperature dissolution of cellulose

Abstract

Cellulose with numerous hydroxyl groups and electronegative atoms can form extensive hydrogen bonds, which are non-negligible obstacles to its dissolution and further utilization. Herein, an in-depth understanding of the interactions between solvent and cellulose, including binding energy, Gibbs free energy, and reaction rate constant, was pursued to screen for appropriate hydrogen bond donor–acceptor couples to form a new type of metal salt hydrate-based eutectic solvent that functions as molecular scissors to dissolve cellulose at room temperature. The optimal solvent exhibits a strong hydrogen bond accepting ability that is capable of breaking the strong hydrogen bonds within cellulose, and thus can spontaneously and efficiently dissolve various types of cellulose, with clear advantages of low cost, environmental friendliness, simple operation, energy efficiency, scalable productivity, and recyclability.