Performance of Sprayed PVDF-Al2O3 Composite Coating for Industrial and Civil Applications

Because of their great water repellency, Superhydrophobic coatings have a major impact on a variety of industrial applications. The current study’s key originality is the development of low-cost, stable, superhydrophobic, and corrosion-resistant composite coatings. In the present work, polyvinylidene fluoride (PVDF)/Al2O3 composite coatings were produced using the spray technique to investigate the wettability and corrosion behavior of the coated materials for industrial and civil applications. PVDF was mixed with various concentrations of Al2O3 nanoparticles, and the mixture was sprayed onto steel, aluminum, and glass substrates. The wettability and morphology of the coated surfaces were investigated using the sessile droplet method and scanning electron microscopy, respectively. The corrosion resistance of bare substrates was compared to that of those coated with PVDF alone and those coated with PVDF/Al2O3 nanoparticles using Tafel polarization techniques. The force of adhesion between the coat and the substrates was measured in pounds per square inch. A nanoindentation test was also used to measure the hardness of the coating layer. The PVDF/Al2O3 coated steel showed a significantly higher water contact angle and lower contact angle hysteresis, reaching 157 ± 2° and 7 ± 1°, respectively, compared to the coated aluminum and glass substrates. Corrosion test results showed that the superhydrophobic PVDF/Al2O3 coatings had a much higher corrosion protection efficiency for steel and aluminum than that of the PVDF ones. The PVDF/Al2O3 coated substrates showed moderate but still acceptable adhesion between the coating layer and the substrates. Moreover, the PVDF/Al2O3 coatings had much better mechanical properties than the PVDF only coatings. Such type of coating could be a promising candidate for possible industrial and civil applications.

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Microstructure Study and Morphology of Ni / Nano Al2O3 Composite Coating Synthesied by Electroless Plating

Diyala Journal of Engineering Sciences ◽

10.24237/djes.2021.14301 ◽

2021 ◽

Vol 14 (3) ◽

pp. 1-7

Author(s):

Hala M. Kadhim

Keyword(s):

Composite Coating ◽

Phase Structure ◽

Composite Coatings ◽

Chemical Properties ◽

Diffraction Method ◽

Nanocomposite Coating ◽

Process Conditions ◽

Al2o3 Nanoparticles ◽

X Ray Diffraction ◽

Al2o3 Composite

The electroless deposition method was used to prepare Ni-based nanocomposite coatings, this approach represents an alternate way of having coatings on the different substrates. Most of the previous literatures on this subject and work deals with a study the effect of the process conditions and, Bath composition on the microstructure at the macroscale of Ni-Al2O3 composite coatings. Though, effect on the step structure of the composition of the bath and microstructure are little, the present work aims to study the effect of hard ceramic Al2O3 nanoparticles at different concentrations (0.0, 0.5, 1.0, 2, 4) g/L, on the phase structure, microstructure and morphology of Al2O3 nanocomposite coating, in order to enhance the mechanical, plysical and chemical properties of nanocomposite coating. In this paper, An X-Ray diffraction method, spectroscopy (EDS), energy dispersive, and scanning electron microscope (SEM) were studied in the phase structure, chemical composition and morphological nanocomposition coatings. In the present paper, is evident from EDS study that the composite coating consists of Ni and nanoparticles of Al2O3. The micrograph study of the EDS showed that A flat and smooth surface is present in the deposited nanocomposite coating. Uniform distribution of nanoparticles of alumina within Ni-Matrix. And the XRD study showed the crystalline structure of the Ni- Al2O3 nanocomposite coating.

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Oscillating Magnetic Drop: How to Grade Water-Repellent Surfaces

Coatings ◽

10.3390/coatings9040270 ◽

2019 ◽

Vol 9 (4) ◽

pp. 270 ◽

Cited By ~ 1

Author(s):

Angelica Goncalves Dos Santos ◽

Francisco Javier Montes-Ruiz Cabello ◽

Fernando Vereda ◽

Miguel A. Cabrerizo-Vilchez ◽

Miguel A. Rodriguez-Valverde

Keyword(s):

Contact Angle ◽

Ad Hoc ◽

Contact Angle Hysteresis ◽

Aqueous Suspension ◽

High Mobility ◽

Surface Friction ◽

Water Repellent ◽

Glass Substrates ◽

Drop Adhesion ◽

Solid Liquid

Evaluation of superhydrophobic (SH) surfaces based on contact angle measurements is challenging due to the high mobility of drops and the resolution limits of optical goniometry. For this reason, some alternatives to drop-shape methods have been proposed such as the damped-oscillatory motion of ferrofluid sessile drops produced by an external magnetic field. This approach provides information on surface friction (lateral/shear adhesion) from the kinetic energy dissipation of the drop. In this work, we used this method to compare the low adhesion of four commercial SH coatings (Neverwet, WX2100, Ultraever dry, Hydrobead) formed on glass substrates. As ferrofluid, we used a maghemite aqueous suspension (2% v/v) synthesized ad hoc. The rolling magnetic drop is used as a probe to explore shear solid–liquid adhesion. Additionally, drop energy dissipates due to velocity-dependent viscous stresses developed close to the solid–liquid interface. By fitting the damped harmonic oscillations, we estimated the decay time on each coating. The SH coatings were statistically different by using the mean damping time. The differences found between SH coatings could be ascribed to surface–drop adhesion (contact angle hysteresis and apparent contact area). By using this methodology, we were able to grade meaningfully the liquid-repelling properties of superhydrophobic surfaces.

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A Stable Anti-Fouling Coating on PVDF Membrane Constructed of Polyphenol Tannic Acid, Polyethyleneimine and Metal Ion

Polymers ◽

10.3390/polym11121975 ◽

2019 ◽

Vol 11 (12) ◽

pp. 1975 ◽

Cited By ~ 3

Author(s):

Lili Wu ◽

Qiuhu Lin ◽

Cong Liu ◽

Wanyu Chen

Keyword(s):

Contact Angle ◽

Metal Ions ◽

Tannic Acid ◽

Metal Ion ◽

Polyvinylidene Fluoride ◽

Coating Layer ◽

Retention Rate ◽

Pure Water ◽

Composite Membranes ◽

Modified Membrane

A hydrophilic and anti-fouling coating layer was constructed on a polyvinylidene fluoride (PVDF) microfiltration membrane by a novel surface modification method. The pristine membrane was firstly coated by (3-chloropropyl) trimethoxysilane/polyethyleneimine and tannic acid. Then, the metal ion was induced on the coating layer to coordinate with tannic acid and polyethyleneimine, forming a more stable and hydrophilic coating on the surface. The membrane’s surface morphology and chemical element analysis showed that the Tannic acid/ polyethyleneimine (TA/PEI) coating layer was denser and had more stability after the addition of metal ions, and this may be due to the coordination bond formed between the TA/PEI coating and metal ions. The results of the water contact angle and pure water flux measurements showed that the hydrophilicity and wettability of the modified membranes were improved obviously after introducing the metal ion layers. The anti-fouling performance and stability of the modified membrane were also characterized by the underwater oil contact angle (OCA), the separation efficiency, and the contact angle variation value for before and after the rinsing experiment. The modified membrane showed obvious stability and antifouling. Moreover, the retention rate of some composite membranes could reach 99.6%.

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