Eco-friendly and durable PCPS nanoparticles for the effective separation of oil-water emulsions

Oil pollution is one of the main environmental problems that is attracting increasing attention from people. In this study, a new composite, namely a PNIPAm-Clay-γPGA-SiO₂ (PCPS) nanomaterial, was prepared through chemical modification. The material exhibited excellent separation efficiencies for both oil-in-water (O/W) and water-in-oil (W/O) emulsions. The maximum separation efficiency of the W/O emulsion reached 98.70%, while that of the O/W emulsion was 99.23%, and the average separation fluxes were 107.44 L m^-2 h^-1 and 1529.34 L m^-2 h^-1, respectively. The superhydrophobicity of the PCPS nanoparticles could be maintained under strong acid/alkali conditions for over 30 days. The high separation efficiency could be maintained even after 7 cycles, indicating the long-term availability of the material. Furthermore, the PCPS nanoparticles showed excellent biocompatibility due to the presence of γ-polyglutamic acid (γPGA) and poly(N-isopropylacrylamide) (PNIPAm). The properties of strong acid/alkali and thermal stabilities, recyclability, and biocompatibility gave the material great potential for applications.