Fabrication of robust superhydrophobic coatings using PTFE‐MWCNT nanocomposite: Supercritical fluid processing

Abstract

Fabrication of polymer‐carbon composite nanostructure with good dispersion of each other is critical for the desired application due to the nanostructure flaws, agglomeration, and poor absorption between the 2 materials. Fabrication of superhydrophobic surface coating composites of polytetrafluoroethylene (PTFE) with multiwalled carbon nanotubes (MWCNTs) through supercritical fluid processing was explored in this study. Homogeneity of the composite was characterized by X‐ray diffraction and Raman spectroscopy studies, which reveal that the PTFE and MWCNT are uniform in the composite. Microstructural surface evaluation of field‐emission scanning electron microscope and high‐resolution transmission electron microscope studies display that the coating composite possesses roughness structures and fibrillation of the superhydrophobic surface coating. Superhydrophobic character was evaluated on fiber‐reinforced plastic (FRP) sheets, which showed that the prepared coating composite surface showed self‐cleaning properties with a high water contact angle of 162.7°. The surface wettability was studied by increasing different temperatures (30°C to 300°C) in PTFE‐MWCNT composite, which reveals that the FRP sheets were thermally stable up to 200°C and afterward; they transformed from superhydrophobic to hydrophilic state at 250°C. The superhydrophobic surfaces are thermally stable in extreme environmental conditions, and this technique may be used and extendable for large‐scale applications.

Waterborne Superhydrophobic and Superoleophobic Coatings for the Protection of Marble and Sandstone

“…The dominant bands appearing at around 2900 cm −1 , which were assigned to the C–H modes of the methylene groups as well as the various C–O, C–H, Si–O, C–C, Si–C modes appearing in the low energy region (below 1500 cm −1 ), indicate that the Silres coating consists predominantly of an organo alkoxy silane [ 43 ]. Furthermore, the peak at 730 cm −1 may be attributed to symmetric stretching vibrations of C–F 2 scissoring and the band at ~1214 cm −1 is probably a result of asymmetric stretching vibrations of C–F 2 [ 44 ]. Consequently, the results of the FT-IR and Raman spectra in Figure 1 are in agreement with the product’s (Silres BS29A) description provided by the manufacturer (Wacker) and suggest that the Silres coating is a mixture of alkoxy silanes and fluoropolymer.…”

Constructing a superhydrophobic free-standing cathode for highly efficient H2O2production over a wide pH range

“…The peaks located at 295, 391, 599, 735, 1126, 1222, and 1300 cm −1 correspond to the characteristic peak of PTFE, which is in accordance with the standards of PTFE. [26][27][28][29] The peaks at 1340-1380 cm −1 are from distorted carbon (D), while the peaks at 1570-1580 cm −1 are the characteristic peaks of graphitic carbon (G). [30][31][32] The Raman results further demonstrate a thin coating of PTFE on Co-NC/CFP-PTFE.…”

Approaches for Evaluating and Engineering Resilient Superhydrophobic Materials

“…A commonly used physical strengthening additive are carbon nanotubes, as they have an intrinsically high structural integrity, and can also contribute additional roughness to the surface microstructure. The incorporation of carbon nanotubes has been shown to increase resilience to applied forces, while improving surface hydrophobicity [89,91].…”