Effect of Stirring on Hydrophobicity of PVDF/CNT Nanocomposite Coatings

Multi-walled carbon nanotubes (MWCNTs)-Polyvinylidene fluoride (PVDF) superhydrophobic coatings were prepared by a facile phase separation and spray coating method. The effect of phase separation and stirring on wettability has been studied. A transformation of hydrophobic to super-hydrophobic state is achieved with increasing CNT content. In the absence of CNTs, the neat PVDF coatings exhibited water contact angle (WCA) of 105o. A gradual increase in WCA is observed with increasing addition of CNTs, and reaches to super-hydrophobic state (WCA > 150o) for CNT content of 33%. FTIR studies revealed a stronger interaction between PVDF and CNT with increasing stirring time. FESEM images and EDAX data show uniform morphology and higher fluorine content, respectively for samples stirred for longer time when compared to shorter stirring time, and the results are discussed in detail.

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Stable and Durable Conductive Superhydrophobic Coatings Prepared by Double-Layer Spray Coating Method

Nanomaterials ◽

10.3390/nano11061506 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1506

Author(s):

Xiang Liu ◽

Kai Chen ◽

Dekun Zhang ◽

Zhiguang Guo

Keyword(s):

Composite Coating ◽

Double Layer ◽

Low Cost ◽

Spray Coating ◽

Sliding Angle ◽

Water Contact ◽

Superhydrophobic Coatings ◽

Coating Method ◽

Specialty Fields ◽

Application Fields

Herein, a low cost, durable, and stable conductive superhydrophobic composite coating (CSC coating) was fabricated on a Q345 steel surface by simple double-layer spray coating. The water contact angle (WCA) of the CSC coating was 160° and the sliding angle (SA) was 3°. In addition to its excellent conductivity (3.10 × 103 Ω), the fabricated composite coating had good durability and wear resistance. After 10 sand-washing cycles, the CSC coating surface still exhibited stable superhydrophobicity (149° WCA, 9.5° SA). At 200 g pressure, the surface of the optimized CSC coating still maintained fine superhydrophobicity (150° WCA, 9.2° SA) and conductivity (1.86 × 104 Ω) after 10 abrasion cycles. In addition, it also exhibited fine adhesion (0.307 MPa) between the composite coating and the substrate. This functional superhydrophobic surface can be applied in specialty fields with harsh conditions such as coal mining and petrochemical activities. This new coating may also expand the application fields of superhydrophobic surfaces and have broad practical application prospects.

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Modification of the Surface Morphology and Properties of Graphene Oxide and Multi-Walled Carbon Nanotube-Based Polyvinylidene Fluoride Membranes According to Changes in Non-Solvent Temperature

Nanomaterials ◽

10.3390/nano11092269 ◽

2021 ◽

Vol 11 (9) ◽

pp. 2269

Author(s):

Jungryeong Chae ◽

Taeuk Lim ◽

Hao Cheng ◽

Wonsuk Jung

Keyword(s):

Graphene Oxide ◽

Functional Groups ◽

Polyvinylidene Fluoride ◽

Water Flux ◽

Bath Temperature ◽

Coagulation Bath ◽

Water Contact ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes ◽

Pure Pvdf

The effect of changes in non-solvent coagulation bath temperature on surface properties such as morphology and hydrophilicity were investigated in multi-walled carbon nanotubes (MWCNTs) and graphene oxide (GO)-based polyvinylidene fluoride (PVDF) membranes. The properties of pores (size, shape, and number) as well as membrane hydrophilicity were investigated using field emission scanning electron microscopy, Raman spectroscopy, optical microscopy, water contact angle, and water flux. Results showed that the pore size increased with an increase in coagulation temperature. The hydrophilic functional groups of the added carbon materials increased the solvent and non-solvent diffusion rate, which significantly increased the number of pores by 700% as compared to pure PVDF. Additionally, these functional groups changed the hydrophobic properties of pure PVDF into hydrophilic properties.

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A simple fabrication of superhydrophobic PVDF/SiO2 coatings and their anti-icing properties

Journal of Materials Research ◽

10.1557/s43578-020-00034-z ◽

2021 ◽

Author(s):

Xinyu Tan ◽

Zhengtao Huang ◽

Lihua Jiang ◽

Ting Xiao ◽

Yunkuan Wang ◽

...

Keyword(s):

Polyvinylidene Fluoride ◽

Low Cost ◽

Dip Coating ◽

Large Temperature ◽

Sliding Angle ◽

Water Contact ◽

Superhydrophobic Coatings ◽

Coating Method ◽

Large Water ◽

Dip Coating Method

AbstractSuperhydrophobic coatings have been regarded as potential promising solutions to many problems, e.g., ice accumulation in the winter seasons. To be practically useful and economically attractive, it is necessary to fabricate such coatings using facile methods, i.e., with minimal steps and low cost. In this work, a polyvinylidene fluoride (PVDF)/SiO2 coating is successfully prepared with a simple dip coating method. It shows impressive superhydrophobic properties with a large water contact angle (WCA) of 159° and a small sliding angle (SA) of less than 3°. Meanwhile, its superhydrophobic properties are robust in a large temperature range of – 30 to 350 °C and in various environments. Moreover, it shows remarkable anti-icing properties by delaying the freezing time (4 times) and reducing (40%) the adhesion of the ice on the substrate. Therefore, this work has displayed a promising approach for fabricating superhydrophobic coatings towards anti-icing applications.

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Nanostructured Materials for the Development of Superhydrophobic Coatings

10.5772/intechopen.96320 ◽

2021 ◽

Author(s):

Jeyasubramanian Kadarkaraithangam ◽

Thangaiyanadar Suyambulingam Gokul Raja ◽

Silambuselvan Parani Bramma Nayagi ◽

Karthikeyan Krishnamoorthy

Keyword(s):

Spray Coating ◽

Underwater Robotics ◽

The Novel ◽

Zno Nanostructures ◽

Water Contact ◽

Superhydrophobic Coatings ◽

Coating Method ◽

Biomedical Coatings ◽

Self Cleaning ◽

Novel Applications

This chapter describes the results of developing superhydrophobic coatings using porous ZnO nanostructures impregnated metal stearates and their applications. The porous ZnO nanostructures with a surface area of 9.7 m2/g and pores in the range from 200 to 400 nm have been prepared via precipitation cum calcination route. The superhydrophobic coatings comprising ZnO/metal stearate film have been deposited using a spray coating method. The developed superhydrophobic films possess a water contact angle of 161° that can be explained using the Cassie-Baxter model. The prepared films exhibited excellent floating properties and high load-bearing characteristics over a prolonged time. Additionally, the self-cleaning properties of the developed superhydrophobic films towards dust removal and self-cleaning urinary coatings are also demonstrated. This chapter collectively presented the novel applications of superhydrophobic coating in the development of biomedical coatings and applications in water surveillance and underwater robotics.

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High Transmittance Superhydrophobic Coatings with Durable Self-Cleaning Properties

Coatings ◽

10.3390/coatings11050493 ◽

2021 ◽

Vol 11 (5) ◽

pp. 493

Author(s):

Michele Ferrari ◽

Paolo Piccardo ◽

Justine Vernet ◽

Francesca Cirisano

Keyword(s):

Power Plants ◽

Spray Coating ◽

Dust Particles ◽

Water Contact ◽

Superhydrophobic Coatings ◽

Spray Method ◽

Coating Method ◽

Solar Power Plants ◽

Self Cleaning ◽

The Impact

One of the most important factors determining a significant reduction in optical devices’ efficiency is the accumulation of soiling substances such as dust, which, especially in solar power plants, implies higher costs and materials ageing. The use of superhydrophobic (SH) coatings, water contact angle (CA) greater than 150°, represents a suitable solution to improve the self-cleaning action while at the same time providing high transmittance for energy conversion. A mixed organic–inorganic SH coating with surface roughness below 100 nm was prepared by an easily scalable spray method and employed, allowing us to modulate the covered area and transparency. The coating has been also investigated while simulating pollution agents like acid rain, harsh environments, and the impact of continuous water droplets and dust particles with different physicochemical properties. The spray coating method allows us to obtain a modulated SH and self-cleaning surface showing CA > 170°, high transmittance in UV-Vis range and the ability to completely restore its initial properties in terms of wettability and transmittance after durability and soiling tests.

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Pharmaceuticals removal by immobilized laccase on polyvinylidene fluoride nanocomposite with multi-walled carbon nanotubes

Chemosphere ◽

10.1016/j.chemosphere.2020.128043 ◽

2021 ◽

Vol 263 ◽

pp. 128043 ◽

Cited By ~ 1

Author(s):

Mahsa Masjoudi ◽

Mitra Golgoli ◽

Zahra Ghobadi Nejad ◽

Sadegh Sadeghzadeh ◽

Seyed Mehdi Borghei

Keyword(s):

Carbon Nanotubes ◽

Polyvinylidene Fluoride ◽

Immobilized Laccase ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

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Effect of TiO2 Powder on the Surface Morphology of Micro/Nanoporous Structured Hydrophobic Fluoropolymer Based Composite Material

Journal of Polymers ◽

10.1155/2013/615045 ◽

2013 ◽

Vol 2013 ◽

pp. 1-4 ◽

Cited By ~ 8

Author(s):

Bichitra Nanda Sahoo ◽

Balasubramanian Kandasubramanian ◽

Amrutha Thomas

Keyword(s):

Phase Separation ◽

Surface Morphology ◽

Polymer Composite ◽

Polyvinylidene Fluoride ◽

Industrial Applications ◽

Nanoporous Structure ◽

Hydrophobic Surfaces ◽

Water Contact ◽

Maximum Water ◽

The Impact

The present work reports a simple and effective way to produce hydrophobic foams with polyvinylidene fluoride (PVDF) and TiO2 by using a phase separation technique. This method involved the phase separation during the deposition of PVDF from its DMF solution with nonsolvent water in the presence of TiO2. The surface morphology of hydrophobic surfaces was characterized by Field Emission Scanning Electron Microscope (FESEM). The maximum water contact angle of 129° was observed. The results confirm that the surface texture of polymer composite exhibits mixture of microporous and nanoporous structure. The impact of TiO2 on the wettability property of polymer composite has been studied. The proposed methodology might find applications in the preparation of hydrophobic surfaces for industrial applications.

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Development of a Stable TiO2Nanocomposite Self-Cleaning Coating for Outdoor Applications

Advances in Materials Science and Engineering ◽

10.1155/2016/7958152 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 5

Author(s):

F. Madidi ◽

G. Momen ◽

M. Farzaneh

Keyword(s):

Mechanical Stability ◽

Low Cost ◽

Spray Coating ◽

Dielectric Behavior ◽

Superhydrophobic Coatings ◽

Angle Measurements ◽

Coating Method ◽

Specific Frequency ◽

Self Cleaning ◽

The Stability

A convenient and low-cost approach for the elaboration of a stable superhydrophobic coating is reported, involving the use of TiO2nanoparticles via the spray coating method. This method can be used for preparing self-cleaning superhydrophobic coatings on large areas for different kinds of substrates. The synergistic effect of the micro/nanobinary scale roughness was produced by a multilayer RTV SR/TiO2composite. The influence of the nanofiller concentration in a specific frequency range (40 Hz to 2 MHz) on the dielectric behavior was analyzed as well. It was found that the real relative permittivity (εr′) increases as the nanofiller concentration increases. Superhydrophobic behavior is analyzed by contact angle measurements, scanning electron microscopy (SEM), and profilometer. The stability of the developed coating also has been evaluated in terms of immersion in various aqueous solutions, heating, adhesion, and exposure to UV irradiation, and the results showed good stability against these factors. The coating retained its superhydrophobicity after several days of immersion in solutions of different pH levels (2, 4, 6, and 12) and different conductivities. In addition, they also exhibited exceptional stability against UV radiation and heating, as well as good mechanical stability.

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