Fabrication of Hierarchically Porous Monoliths Based on Adamantane-Modified Cellulose via Thermally Induced Phase Separation

The development of porous functional materials derived from polysaccharides contributes to sustainable materials design. Thermally induced phase separation (TIPS) enables the formation of cocontinuous monoliths with tunable pore architectures. However, solvent selection tailored to specific polymer species remains a critical bottleneck, necessitating polymer-specific fabrication conditions. In this study, adamantane-modified cellulose (AdC) monoliths were fabricated using a dimethyl sulfoxide (DMSO)/H2O-based TIPS system. The introduction of bulky, hydrophobic adamantane groups onto the cellulose backbone improved solubility and processability, thereby enabling monolith formation. A fabrication window was established by systematically varying polymer concentration, solvent–nonsolvent composition, and cooling temperature. The resulting AdC monoliths exhibited interconnected macroporous frameworks with accompanying mesoscale structural features, forming a hierarchical pore architecture. Permeability measurements demonstrated efficient fluid transport through the monolithic structure. Furthermore, adsorption experiments confirmed that the hydrophobic modification imparted the ability to capture organic molecules under aqueous flow conditions. These findings broaden the design scope of cellulose-based monoliths and provide insight into the applicability of DMSO/H2O solvent systems for the TIPS-based fabrication of polysaccharide monoliths with controllable pore structures.