Search

Superhydrophobic materials possess prospective applications of oily wastewater treatment due to their high efficiency and easy operation. Nevertheless, most superhydrophobic materials are difficult to separate oil-water emulsion, especially for highly viscous water-in-crude oil emulsion. Herein, a superhydrophobic wood with excellent Joule heat and demulsification was proposed by chemically treating the natural wood and subsequent coating of the carboxyl-modified carbon nanotubes (cCNTs) for providing conductive pathways, polyethylenimide (PEI) for supporting demulsification and polydimethylsiloxane (PDMS) for hydrophobic modification. The fabricated superhydrophobic PDMS@PEI-cCNTs wood displayed a water contact angle of 155o and great compression property with a nearly undamaged structure at a strain of 40 % after 50 compression tests, which could separate and recover oil from the oil-water mixture via absorption-extrusion process. Besides, due to the filtration and electrostatic interaction of the PDMS@PEI-cCNTs wood, the water-in-oil emulsion was demulsified quickly with a separation efficiency greater than 99.7 %. Meanwhile, the PDMS@PEI-cCNTs wood showed a good Joule heat capability, and the surface temperature reached 160 °C at 35 V of voltage within 120 s, which largely reduced the viscosity of water-in-crude oil emulsion. Thus, the PDMS@PEI-cCNTs wood was successful in separating the water-in-crude oil emulsion via Joule heat capability with a separation rate of 4.33 × 104 kg·m−3·h−1 and a separation efficiency of 93.4 %. The material developed in this study has wide range of applications in treating the stable crude oil-water emulsion with high viscosity. [Display omitted] • A new strategy for fabricating superhydrophobic wood for various oil-water emulsions separation is proposed. • The wood presents stable superhydrophobicity and good electrical conductivity. • The wood shows excellent demulsification capability via charge action, absorption and gathering. • The wood exhibits great Joule heat to promote separating viscous water-in-crude oil emulsion. [ABSTRACT FROM AUTHOR]

We report a facile approach to designing the robust organic-inorganic hybrid superhydrophilic coating films under UV radiation. It is based on the utilization of ene-terminated hydrophilic oligomer (ETHO) and hierarchically mesoporous silica nanoparticles (HMSNs). ETHO was firstly synthesized with dl -dithiothreitol and excess of poly(ethylene glycol) dimethacrylate at room temperature via thiol-ene reaction, and then by spraying the methanol solution containing ETHO, HMSNs, trimethylolpropane triacrylate as crosslinking agent, and Darocur 1173 as photoinitiator on substrate, the thiol-ene/HMSNs hybrid superhydrophilic coating films were fabricated under the exposure of UV light. The structure of ETHO was confirmed by FT-IR, 1 H NMR and 13 C NMR, its molecular weight was 7600 measured by GPC. The wetting behavior of the coating films was found to be largely determined by the mass ratio of HMSNs to ETHO. With the mass ratio at 0.75, the hybrid coating films could achieve superhydrophilic state within 0.24 s, and SEM revealed the existence of double micro-nano structure on the surface, which was significant for the improvement of superhydrophilicity. Importantly, the superhydrophilicity of the coating film could be steadily maintained under the conditions of acid solution, boiling water and abrasion. Additionally, the coating films also exhibited excellent adhesion, flexibility and impact strength. [ABSTRACT FROM AUTHOR]

With the environment pollution deteriorating by industrial waste water and oil leak, superhydrophobic materials for oil/water separation have attracted more attentions and become a worldwide research hotspot. Herein, we propose a facile dipping-UV curing approach to fabricating superhydrophobic hybrid coating on polyester fabric for oil/water separation by utilizing (3-mercaptopropyl) trimethoxysilane modified graphene oxide (mGO) and vinyl-terminated polydimethylsiloxane (V-PDMS). With mass ratio of mGO to V-PDMS increasing, the roughness of the fabricated mGO/PDMS hybrid coating on polyester fabric correspondingly increased and the water contact angle (WCA) reached up to 157°, demonstrating excellent water repellency. Importantly, due to the formation of crosslinked PDMS network with mGO as crosslinking points, the fabric exhibited good thermal stability and chemical resistance. Furthermore, the superhydrophobic fabric also possessed high oil/water separation efficiency at 99.8%, and still kept at 98.4% even after 15 separation cycles. Our findings stand out as a new tool to fabricate superhydrophobic materials and coatings with graphene and its derivatives for oil/water separation, showing great potential in practical applications such as oil spill accidents and industrial sewage emissions. [ABSTRACT FROM AUTHOR]

Superhydrophobic material has great potential applications in the field of anti-icing due to its special wettability. However, the poor wear resistance of the material has restricted its practical applications. Based on this, a simple two-step spray method was used to prepare a self-healing and robust superhydrophobic coating with excellent photothermal/electrothermal effect for anti-icing using epoxy modified ethylene octene copolymer (POEG) resin as the substrate layer and the fluorinated carbon black as the top coating. Results showed that the obtained composite coating showed multi-level rough structure and possessed excellent superhydrophobicity toward water droplets with different pH. Meanwhile, the composite coating could resist abrasion and kept superhydropbobicity even 250 cycles abrasion test with a water contact angle higher than 150o. When the surface was subjected to the intense abrasion, the rough structure and the superhydrophobic property of the surface were destroyed. However, it could be restored by the abrasion of the rougher surface. In addition, the scratches on the surface could be completely repaired by the heat treatment, indicating the good self-healing performance of the composite coating. Due to the existence of the carbon black particles, the superhydrophobic coating had good photothermal/electrothermal effects, which endowed the surface with excellent anti-icing performance of removing the icing under the conditions of electrothermal and light. This paper provides a simple and convenient way to prepare functional self-healing superhydrophobic coating, and a new idea for the preparation of anti-icing coating. [Display omitted] • The stable superhydrophobic coating showed excellent abrasion resistance performance. • The damaged composite coating could be easily repaired by heating self-healing. • The superhydrophobic coating possessed excellent electrothermal/photothermal effects. • The superhydrophobic coating showed excellent anti-icing performance. [ABSTRACT FROM AUTHOR]