Bacterial Cellulose-Poly(Ionic Liquid)s Composites with Tunable Structure and Enhanced Mechanics for Dye Adsorption

Herein, bacterial cellulose-poly(ionic liquid)s composite membranes (BC-PILMs) with tunable structures and improved mechanical properties were developed for dye adsorption via in situ thiol–ene click polymerization within a reactive ionic liquid microemulsion. The unique combination of bacterial cellulose and ionic liquids enables dual cross-linking through covalent bonds and hydrogen bonding, while the microemulsion droplets direct the formation of a porous architecture. By varying the contents of key compents, the internal morphology, mechanical performance, hydrophilicity, and swelling behavior of BC-PILMs were finely regulated. A suite of characterization techniques, including SEM, FTIR, XPS, MIP, AFM, TGA, and DSC, was used to probe the materials’ structural and physicochemical properties. The optimized BC-PILMs combine ultrahigh elongation (≈300%) and tensile strength (≈1 MPa) with enhanced hydrophilicity and water retention (>60% at 105 °C), exhibit exceptional adsorption capacity (up to 1268 mg/g) toward the model dye, Disperse Red, and display unique solvent-responsive behavior. Kinetic and adsorption isotherm models were employed to analyze the adsorption behavior, and a possible adsorption mechanism was further elucidated. This work provides a versatile strategy for designing multifunctional membranes and opens avenues for their application in environmental remediation and intelligent separation technologies.