Development of Cellulose‐Based Hydrogels With a New Epoxide‐Based Crosslinker: From Facile Room‐Temperature Synthesis to Detailed Characterization

Abstract

Cellulose is an abundant raw material for the synthesis of natural hydrogels, which can react with epoxide‐based crosslinking agents to form three‐dimensional structures. This study focuses on the synthesis of hydrogels from microcrystalline cellulose (MCC) using a novel crosslinker, neopentyl glycol diglycidyl ether (NGDE), with a facile procedure. Using tetrabutylphosphonium hydroxide (TBPH) 50 wt. % as a solvent, the cellulose was rapidly dissolved at room temperature, and the gelation reaction proceeded easily without requiring additional catalysts. Fourier transform infrared and nuclear magnetic resonance spectroscopy in liquid and solid states confirmed the formation of a crosslinked network between MCC and NGDE. Characterization by scanning electron microscopy, thermogravimetric analysis, UV–Vis transmittance, and compressive stress measurements showed variations in the morphology, thermal properties, transparency, and mechanical stability of the hydrogels depending on the amounts of cellulose and crosslinker. Regarding the swelling characteristics, the hydrogel containing 5 wt. % MCC with an NGDE‐to‐anhydroglucose unit molar ratio of 1:1 (C5N1) exhibited the highest swelling capacity, with a water content of 91.43% ± 0.04% and a swelling degree of 288.52% ± 1.95%. Overall, the study demonstrates that NGDE is a potential crosslinking agent, allowing for the modification of the structure and properties of cellulose‐based hydrogels toward greater safety and sustainability.