κ‐Carrageenan/poly(sodium styrenesulfonate‐co‐acrylic acid) macroporous anionic monoliths: Dye adsorption and oil–water separation properties

Abstract κ‐Carrageenan (κC) is a widely used food hydrogel, but its use as an environmental adsorption separation material still needs to be further developed. Herein, a novel macroporous anionic monolith was synthesized by the oil‐in‐water high internal phase emulsion template method. The monolith was obtained by the continuous phase polymerization of sodium styrenesulfonate (NaSS) and acrylic acid (AA), in which κC was introduced to form a semi‐interpenetrating network structure to improve its overall performance. The results showed that the mechanical strength of the monolith increased with κC content. Because of the use of two strong hydrophilic monomers, NaSS and AA, the porous monolith proved to be superoleophobic underwater. In addition, the porous materials had a strong cationic dye adsorption capacity (2455 mg/g for malachite green, 1180 mg/g for methylene blue) and a fast removal rate, good reusability, and oil–water separation. This work highlights their potential application value in the purification of complex water environments.