Thermally induced gel from cellulose/NaOH/PEG solution: preparation, characterization and mechanical properties

In this paper, we reported a thermally induced gel with strong mechanical properties prepared from cellulose/NaOH/PEG aqueous solution following the procedures of dissolution, heating and freeze-drying. The as-prepared gel showed undeveloped networks composed of cross-linked fiber aggregations tightly coated with plenty of NaOH·H2O and PEG-aggregated fine particles, which led to the significant enhancement of thermal stability and the disappearance of the original cellulose crystalline structures. Furthermore, the elastic modulus, yield stress and toughness of the mechanically strong gel were measured to be up to 3,210, 325 kPa and 389 kJ m−3, respectively, comparable to those of cross-linked polymer gel materials with strong mechanical strength such as the microfibrillated cellulose aerogels and the three-dimensional architectures of graphene hydrogels.