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Using the immersion phase inversion process, polysulfone (PSF), grapheme oxide (GO) and modified carbon nanotubes (MCNTs) were dissolved in 1-methyl-2-pyrrolidone (NMP) to prepare nanocomposite membranes. The GO-MCNTs blended PSF membranes were characterized by several analytical methods, such as morphology analysis, group characteristic peak test, hydrophilic measurement and permeation tests, and the synergistic effect of GO and MCNTs on the membrane performance was investigated. Microscope images depict two-layer structure of the composite membrane, in which, the lower layer is finger like porous layer, and the upper layer is a thinner separation layer. M-CNTs have great influence on formation of the upper separation layer, while the hydrophilic nature of GO results in the formation of the lower supporting layer, which changes from finger shaped hole to honeycomb pore. The change of membrane structure not only improves the surface hydrophilicity, but also promotes the membrane performance. In particular, the composite membrane (mGO:MCNTs = 2:1) exhibits a much smaller contact angle (48.01°), a high permeation flux (33.25 L/m2·h) and superior rejection rate (95.2%). Furthermore, the fine compaction performance of composite membrane also provides great potential application prospects in water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tough short-fluorinated nanocoatings were fabricated by solvent-free iCVD. • Isocyanate chemistry induced self-crosslinking and fixated surface fluorinated chains. • Self-crosslinking enabled excellent dynamic water repellency and mechanical strength. • Conformal nanocoating imparted fabrics ultradurable superhydrophobicity. As long-perfluorinated side chain polymers are phasing out due to healthy and environmental concerns, short-fluorinated polymers are garnering increasing attention as a substitute for superhydrophobic coatings. Challenges, however, are to be addressed due to the poor dynamic water repellency and unsatisfactory durability of short-fluorinated polymer coatings. This work reports the fabrication of self-crosslinkable poly(perfluorohexylethyl acrylate- co -isocyanato ethyl methacrylate) nanocoating with good dynamic water repellency and high mechanical strength using a solvent-free initiated chemical vapor deposition (iCVD) method. The employment of highly reactive isocyanate groups in the coating not only facilitated covalent binding with functional groups on the substrate surface, but also enabled self-crosslinking reactions in the presence of water vapor. Crosslinking immobilized the fluorinated chains on the surface, thus alleviating the contact angle hysteresis. The crosslinked network also significantly improved the mechanical strength of the coating. Without affecting fabric morphology, the coating enabled superhydrophobicity of different fabrics with water sliding angle as low as 3˚. Such superhydrophobicity was well maintained after various harsh durability tests, including sandpaper abrasion for up to 20,000 cm, ultrasonication and boiling for more than 12 h, etc. The achieved durability was attributed to the enhanced adhesion strength and excellent mechanical property of the coating. This work thus paves a novel way towards eco-friendly fabrication of durable superhydrophobic fabrics. [ABSTRACT FROM AUTHOR]