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The superhydrophobic surfaces with three kinds of nanopillars on polypropylene (PP) substrates are fabricated by a plasma nanotexturing technique comprising oxygen‐plasma treatment (OPT) followed by fluorocarbon polymer deposition (FPD). The diameters of nanopillars and spacing distances between nanopillars are tuned under the different OPT and FPD duration times. The wettability and contact electrification on the surfaces are analyzed under the water droplet impact by changing the impacting droplet number, Weber number, and salt concentration. The dense or wide nanopillars favor high contact charge on the surfaces with nanopillars, arousing the damage of the superhydrophobicity with low adhesion. The low contact charge impacting the droplets with high salt concentration has a weakened effect on the superhydrophobicity of the surfaces with nanopillars. [ABSTRACT FROM AUTHOR]

The carbon fiber‐reinforced polyetheretherketone (CF/PEEK) composite coatings with two types of short CFs, that is, 300‐ and 600‐mesh, each in the contents of 10 and 30 wt% are deposited in comparison with the pure PEEK coatings by using a flame spraying method, respectively. The 300‐mesh CFs with intact morphology and the 600‐mesh CFs preserving fractured shape and higher graphitization degree are selected as the reinforced fillers in the CF/PEEK composite coatings. The flame‐sprayed CF/PEEK composite coatings show the increased porosity with the higher CF contents. The adding of CFs in the flame‐sprayed CF/PEEK composite coatings limits the thermal degradation of PEEK and restrains the PEEK crystallization showing low crystallinity degree and small crystallite size. The composite coatings in 10 wt% CF content exhibit the optimized nanoindentation behavior and tribological property. The 300‐mesh CFs with large length and intact morphology in flame‐sprayed CF/PEEK composite coatings lead to the increased surface hardness by 1.31 times over that of the pure PEEK coatings. The 600‐mesh CFs with higher graphitization degree contribute to better tribological property of flame‐sprayed CF/PEEK composite coatings with an order of magnitude lower specific wear rate. [ABSTRACT FROM AUTHOR]

Inspired by the antireflection and antiwetting functionalities of dragonfly wings decorated with random nanopillars and a wax layer, a facile technique to endow the same functionalities has been devised. In this two‐step plasma nanotexturing technique, first oxygen plasma treatment is implemented to grow the random nanopillars on the polymethyl methacrylate (PMMA) surfaces, and then C4F8 plasma polymer deposition is carried out so that the thin fluorocarbon film with a low surface free energy and refraction index covers the random nanopillars. The biomimetic PMMA surfaces exhibit excellent broadband and omnidirectional antireflection properties and robust antiwetting properties under the water droplet impact. The superhydrophobicity at the slippery Cassie state was maintained under the natural oscillation of residual droplets. [ABSTRACT FROM AUTHOR]

Novel and intelligent plasma copolymers based on hydrophilic/hydrophobic monomers with tunable wettability and pH-responsiveness are demonstrated. A series of plasma copolymer coatings with various carboxylic acid and fluorocarbon group ratio are prepared on the low-density polyethylene (LDPE) surfaces via capacitively coupled radio frequency plasma (CCP). The static water contact angles (SWCA) of C4F8-co-AA plasma polymer coatings on nanotextured LDPE surfaces tuned from 163 to 4°. These C4F8-co-AA plasma polymer coatings showed different pH-responsiveness by the combined effect of the carboxylic acid to fluorocarbon group ratios and surface nanotexture. The increase of carboxylic acid groups of C4F8-co-AA plasma polymers shifted the reversibly switchable wettability of pH-responsiveness towards low SWCA range. The magnifying effect of surface nanotexture on pH-responsiveness was also observed. [ABSTRACT FROM AUTHOR]

Front Cover: Monomer feed rate regulates the chemical structure of smart plasma copolymer coating and its surface wettability in various pH environment. The combined effect of surface chemical compositions and surface roughness causes tunable wettability from superhydrophobicity to superhydrophilicity of smart plasma copolymer coatings. Further on, the presence of the carboxylic acid functional group in plasma copolymer coatings made this surface wettability switchable for different pH environment. Further details can be found in the article by I. Muzammil et al. on 1700053. [ABSTRACT FROM AUTHOR]