SUPERHYDROPHOBIC AND SUPERLIPOPHILIC POLYPROPYLENE/β-NUCLEATING AGENT/EPDM TERPOLYMER THERMOPLASTIC VULCANIZATE FILMS USED FOR SELF-CLEANING AND GREEN OIL–WATER SEPARATION

ABSTRACT Superhydrophobic materials have significant industrial application value in self-cleaning and oil–water separation. Thus, a β-nucleating agent–modified polypropylene (PP)/EPDM terpolymer thermoplastic vulcanizate (TPV) was fabricated, and a rough surface texture was constructed using metallographic sandpaper as a template. The resulting material exhibited superhydrophobicity, self-cleaning capability, and pressure-responsive oil–water separation performance. The results show that after hot-pressing PP/EPDM TPVs with W10 metallographic sandpaper, the surface contact angle of the TPVs increased to 154.3°, the sliding angle decreased to 3.1°, and the surface energy decreased to 12.2 mN·m −1 , indicating a remarkable improvement in superhydrophobic performance. Furthermore, with the incorporation of a β-nucleating agent into the PP phase of PP/EPDM TPVs, the loose stacking of β-crystal molecular chains facilitated plastic deformation, leading to a further enhancement of surface roughness after sandpaper templating. Consequently, the surface contact angle increased to 157.8°, the sliding angle decreased to 2.8°, and the surface energy was reduced to 11.3 mN·m −1 . Under both sliding and rolling self-cleaning test modes, the TPVs with β-nucleating agent exhibited excellent self-cleaning behavior. In oil–water separation experiments, the β-nucleating agent–modified superhydrophobic TPV films demonstrated rapid separation, high selectivity, and pressure-responsive characteristics across various oil–water mixtures. The critical pressure difference between oil and water phases reached as high as 4.10 kPa, and the separation efficiency remained >95.0%, even under strong suction forces. New insights are presented on the development of efficient and sustainable materials for oil–water separation and self-cleaning applications.