Acrylate-Based Hybrid Sol-Gel Coating for Corrosion Protection of AA7075-T6 in Aircraft Applications: The Effect of Copolymerization Time

Pre-hydrolysed/condensed tetraethyl orthosilicate (TEOS) was added to a solution of methyl methacrylate (MMA) and 3-methacryloxypropyltrimethoxysilane (MAPTMS), and then copolymerised for various times to study the influence of the latter on the structure of hybrid sol-gel coatings as corrosion protection of aluminium alloy 7075-T6. The reactions taking place during preparation were characterised using real-time Fourier transform infrared spectroscopy, dynamic light scattering and gel permeation chromatography. The solution characteristics were evaluated, using viscosimetry, followed by measurements of thermal stability determined by thermogravimetric analysis. The optimal temperature for the condensation reaction was determined with the help of high-pressure differential scanning calorimetry. Once deposited on 7075-T6 substrates, the coatings were evaluated using a field emission scanning electron microscope coupled to an energy dispersive spectrometer to determine surface morphology, topography, composition and coating thickness. Corrosion properties were tested in dilute Harrison’s solution (3.5 g/L (NH4)2SO4 and 0.5 g/L NaCl) using electrochemical impedance spectroscopy. The copolymerization of MMA and MAPTMS over 4 h was optimal for obtaining 1.4 µm thick coating with superior barrier protection against corrosion attack (|Z10 mHz| ~ 1 GΩ cm2) during three months of exposure to the corrosive medium.

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Synthesis, characterization and corrosion protection properties of polyN-(p-bromophenyl)-2-methacrylamide-co-glycidyl methacrylate on low nickel stainless steel

Journal of Polymer Engineering ◽

10.1515/polyeng.2011.042 ◽

2011 ◽

Vol 31 (2-3) ◽

Cited By ~ 2

Author(s):

Sakvai Mohammed Safiullah ◽

Deivasigamani Thirumoolan ◽

Kottur Anver Basha ◽

K. Mani Govindaraju ◽

Dhanraj Gopi ◽

...

Keyword(s):

Stainless Steel ◽

Corrosion Protection ◽

Glycidyl Methacrylate ◽

Electrochemical Impedance ◽

Thermo Gravimetric Analysis ◽

Gel Permeation Chromatography ◽

Gravimetric Analysis ◽

Scanning Calorimetry ◽

Protection Efficiency ◽

Ft Ir

Abstract The synthesis of copolymers from different feed ratios of N-(p-bromophenyl)-2- methacrylamide (PBPMA) and glycidyl methacrylate (GMA) was achieved by using free radical solution polymerization technique and characterized using FT-IR, 1H and 13C NMR spectroscopy. The thermal stability of the synthesized copolymers was studied using thermo-gravimetric analysis (TGA) and differential scanning calorimetry (DSC). The molecular weight of the copolymer is determined by gel permeation chromatography (GPC). The corrosion performances of low nickel stainless steel specimens dip coated with different composition of copolymers were investigated in 0.5 M H2SO4 using potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) techniques. The polarization and impedance measurements showed different corrosion protection efficiency with change in composition of the copolymers. It was found that the corrosion protection properties are owing to the barrier effect of the polymer layer covered on the low nickel stainless steel surfaces. However, it is observed that the mole ratio of PBPMA and GMA plays a major role in the protective nature of the copolymer.

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Corrosion Resistance of AA2024-T3 Coated with Graphene/Sol-Gel Films

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.227.115 ◽

2015 ◽

Vol 227 ◽

pp. 115-118 ◽

Cited By ~ 2

Author(s):

Miguel Hernandez ◽

Juan Genesca ◽

Claudia Ramos ◽

Emilio Bucio ◽

José Guadalupe Bañuelos ◽

...

Keyword(s):

Electrochemical Impedance ◽

Sol Gel ◽

Sulfate Solution ◽

Lauryl Sulfate ◽

Scanning Calorimetry ◽

Corrosion Properties ◽

Dimensional Network ◽

Organic Precursors ◽

Aluminum Plates ◽

Sol Gel Films

Graphene is a two-dimensional network of carbon atoms with optimal thermal, electronic and chemical stability properties that promise different and versatile applications in various fields including the protection of metals from corrosion phenomena. For this reason in this paper graphene was employed and studied as an agent dopand incorporated into hybrid sol-gel coatings to enhance their resistance in saline media and to improve the durability of these films. Graphene was obtained by using an electrochemical method involving oxidation and reduction reactions in a sodium lauryl sulfate solution. On the other hand, the hybrid sol-gel was synthesized from the combination of inorganic and organic precursors, zirconium (IV) n-propoxide (TPOZ) and 3-glycidoxipropiltrimetoxysilane (GLYMO) respectively. In order to obtain the coating system (graphene/sol-gel) two different procedures were applied onto clean aluminum plates: a) the electrodeposition of graphene and b) the graphene-doped sol-gel coating. Differential scanning calorimetry, scanning electron microscopy and electrochemical impedance spectroscopy were used to characterize the results, which demonstrate an improvement of the corrosion properties of the films with the incorporation of graphene compounds.

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Enhancing the Corrosion Protection of AA2024-T3 Alloy by Surface Treatments Based on Piperazine-Modified Hybrid Sol–Gel Films

Metals ◽

10.3390/met10040539 ◽

2020 ◽

Vol 10 (4) ◽

pp. 539

Author(s):

Diógenes J. Carbonell ◽

Rodrigo Montoya ◽

Victoria J. Gelling ◽

Juan Carlos Galván ◽

Antonia Jiménez-Morales

Keyword(s):

Corrosion Inhibitor ◽

Corrosion Protection ◽

Electrochemical Impedance ◽

Condensation Reaction ◽

Sol Gel ◽

Resonance Spectroscopy ◽

29Si Nmr ◽

Crosslinking Degree ◽

Molar Ratios ◽

Sol Gel Films

The aim of this study was to develop new chrome-free surface pretreatments for AA2024-T3 aluminum alloy. These pretreatments were based on hybrid organic–inorganic sol–gel thin films prepared from mixtures of γ-methacryloxypropyltrimethoxysilane (MAPTMS) and tetramethylorthosilicate (TMOS). Different MAPTMS/TMOS molar ratios were used for optimizing the physical–chemical characteristics of the sol–gel films. The formulation of a set of these sols was modified by incorporating piperazine (1,4-diazacyclohexane) as a corrosion inhibitor. The resulting sol–gel films were characterized by using Fourier transform infrared spectroscopy (FTIR), liquid-state 29Si nuclear magnetic resonance spectroscopy (29Si-NMR) and viscosity measurements. The corrosion performance of the sol–gel films was analyzed by using electrochemical impedance spectroscopy (EIS) and local electrochemical impedance mapping (LEIM). The characterization techniques indicated that piperazine behaved as a catalyst for the condensation reaction during the formation of the MAPTMS/TMOS organopolysiloxane network and produces an increase of the crosslinking degree of the sol–gel films. EIS and LEIM results showed that piperazine is an effective corrosion inhibitor, which can be used to enhance the active corrosion protection performance of sol–gel films.

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Degradation of Sol-Gel Acrylic Coatings Based on Si and Zr Investigated Using Electrochemical Impedance, Infrared and X-Ray Photoelectron Spectroscopies

Frontiers in Materials ◽

10.3389/fmats.2021.756447 ◽

2021 ◽

Vol 8 ◽

Author(s):

Peter Rodič ◽

Sandrine Zanna ◽

Ingrid Milošev ◽

Philippe Marcus

Keyword(s):

Corrosion Protection ◽

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Ion Beam ◽

Salt Spray ◽

Sol Gel ◽

Synthesis Process ◽

Corrosion Properties ◽

X Ray ◽

Acrylic Coatings

This study aimed to synthesise and characterise two types of sol-gel acrylic coatings: one based on Si and the other based on Si and Zr. These coatings, which served as a barrier for corrosion protection of aluminium, were synthesised by sol-gel methodology using silicon precursors tetraethyl orthosilicate and organically modified silicon precursor 3-methacryloxypropyltrimethoxysilane, without and with the addition of zirconium(IV) n-propoxide chelated with methacrylic acid. The synthesis process was followed using real-time Fourier transform infrared spectroscopy, which confirmed the condensation reactions of Si–O–Si and Si–O–Zr networks, depending on the sol type. This was reflected in the composition of the coating as well, as shown by X-ray photoelectron spectroscopy. The coating topography, thickness and morphology were analysed using focused ion beam scanning electron microscopy. X-ray photoelectron spectroscopy was employed to follow the degradation of acrylic coatings upon immersion in sodium chloride solution. Corrosion properties, evaluated using electrochemical impedance spectroscopy in 0.1 M NaCl, confirmed high barrier protection of coated aluminium with acrylic coatings based on Si and even better for coating based on Si with Zr. The more durable corrosion protection of the latter was also confirmed by salt spray testing.

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Corrosion Protection of A36 Steel with SnO2 Nanoparticles Integrated into SiO2 Coatings

Coatings ◽

10.3390/coatings10040385 ◽

2020 ◽

Vol 10 (4) ◽

pp. 385 ◽

Cited By ~ 1

Author(s):

Ana Karen Acero-Gutiérrez ◽

Ana Lilia Pérez-Flores ◽

Jesús Gilberto Godínez-Salcedo ◽

Joel Moreno-Palmerin ◽

Ángel de Jesús Morales-Ramírez

Keyword(s):

Corrosion Protection ◽

Corrosion Inhibition ◽

Silicon Oxide ◽

Electrochemical Impedance ◽

Sno2 Nanoparticles ◽

Sol Gel ◽

Barrier Properties ◽

Dip Coating ◽

Uncoated Sample ◽

A36 Steel

Tin oxide (SnO2) nanoparticles were successfully added to silicon oxide (SiO2) coatings deposited on A36 steel by the sol-gel and dip-coating methods. These coatings were developed to improve the performance of corrosion protection of steel in a 3 wt % NaCl solution. The effects of modifying the SnO2 particle concentration from 0–7.5 vol % were investigated by polarization resistance, Tafel linear polarization, and electrochemical impedance spectroscopy (EIS). The formation of protective barriers and their corrosion inhibition abilities were demonstrated. It was found by electrochemical studies that all of the coated samples presented higher corrosion resistances compared with an uncoated sample, indicating a generally beneficial effect from the incorporation of the nanoparticles. Furthermore, it was established that the relationship between the SnO2 content and the corrosion inhibition had parabolic behaviour, with an optimum SnO2 concentration of 2.5 vol %. EIS showed that the modified coatings improved barrier properties. The resistance for all of the samples was increased compared with the bare steel. The corrosion rate measurements highlighted the corrosion inhibition effect of SnO2 nanoparticles, and the Tafel polarization curves demonstrated a decrease in system dissolution reactions at the optimal nanoparticle concentration.

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Corrosion protective properties of coatings doped with inhibitors

Anti-Corrosion Methods and Materials ◽

10.1108/acmm-07-2013-1281 ◽

2014 ◽

Vol 61 (6) ◽

pp. 416-422 ◽

Cited By ~ 6

Author(s):

Mansoureh Parsa ◽

Seyed Mohammad Ali Hosseini ◽

Zahra Hassani ◽

Effat Jamalizadeh

Keyword(s):

Corrosion Resistance ◽

Corrosion Protection ◽

Electrochemical Impedance ◽

Sol Gel ◽

Titania Nanoparticles ◽

Self Healing ◽

Properties Of Coatings ◽

Ethylene Imine ◽

Protective Properties ◽

Content Type

Purpose – The purpose of this paper was to study the corrosion resistance of water-based sol-gel coatings containing titania nanoparticles doped with organic inhibitors for corrosion protection of AA2024 alloy. Design/methodology/approach – The coatings were obtained using tetraethylorthosilicate, 3-glycidoxypropyltrimethoxysilane, titanium (IV) tetrapropoxide and poly(ethylene imine) polymer as cross-linking agents. As corrosions inhibitors, 2-mercaptobenzoxazole and salicylaldoxime were incorporated into the sol-gel for the improvement of the corrosion resistance. The corrosion protection performance of coatings was studied using the potentiodynamic scan and the electrochemical impedance spectroscopy (EIS) methods. Atomic force microscopy was used to investigate surface morphology of the coatings. Findings – The results indicated that doping the sol-gel coatings with inhibitors leads to improvement of the corrosion protection. The comparison of doped coatings confirmed that corrosion protection performance of the sol-gel coatings doped with 2-mercaptobenzoxazole was better than for the sol-gel coatings doped with salicylaldoxime. Also the EIS results verified self-healing effects for the sol-gel coatings doped with 2-mercaptobenzoxazole. Originality/value – This paper indicates 2-mercaptobenzoxazole and salicylaldoxime can be added as corrosion inhibitors to sol-gel coatings to improve their corrosion protective properties for AA2024 alloy.

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Impedance Behavior of the Composite Coatings Prepared on Magnesium Alloy AZ91 in Simulated Seawater Solution

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.900.526 ◽

2014 ◽

Vol 900 ◽

pp. 526-530

Author(s):

Wei Shang ◽

Zhou Lan Yin ◽

Yu Qing Wen ◽

Xu Feng Wang

Keyword(s):

Magnesium Alloy ◽

Corrosion Protection ◽

Corrosion Behavior ◽

Electrochemical Impedance ◽

Composite Coatings ◽

Sol Gel ◽

Soaking Time ◽

Magnesium Alloy Az91 ◽

Micro Arc Oxidation ◽

Simulated Seawater

The composite coatings were obtained on a magnesium alloy by micro-arc oxidation and sol-gel technique. Electrochemical impedance spectroscopy (EIS) was used to evaluate the corrosion behavior of MAO coating and composite coatings in a simulated seawater solution. The results show that corrosion behavior of the MAO coating and composite coatings are different at different immersion times. Corrosion protection of the MAO coating gradually weaken with the extension of soaking time, but corrosion protection of the composite coatings become stronger first and then weaken.

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Corrosion Behavior of Amorphous Sol–Gel TiO2–ZrO2 Nano Thickness Film on Stainless Steel

Coatings ◽

10.3390/coatings11080988 ◽

2021 ◽

Vol 11 (8) ◽

pp. 988

Author(s):

Lidija Ćurković ◽

Helena Otmačić Ćurković ◽

Irena Žmak ◽

Mihone Kerolli Mustafa ◽

Ivana Gabelica

Keyword(s):

Stainless Steel ◽

Corrosion Behavior ◽

Electrochemical Impedance ◽

Sol Gel ◽

Chelating Agent ◽

Dip Coating ◽

Emission Spectrometry ◽

Aisi 316L ◽

Corrosion Properties ◽

Sol Gel Process

In this work, a single-layer TiO2–ZrO2 thin film is deposited on the AISI 316L austenitic stainless steel by the sol–gel process and the dip coating method to improve its corrosion resistance properties. For the sol preparation, titanium isopropoxide and zirconium butoxide are used as the precursors, yttrium acetate hydrate is used for the ZrO2 stabilization, i-propanol as the solvent, nitric acid as the catalyst, acetylacetone as the chelating agent, and the distilled water for the hydrolysis. The deposited films are annealed at 400 °C or 600 °C. Morphology and phase composition of the sol–gel TiO2–ZrO2 films and powders are analyzed by scanning electron microscopy (SEM) equipped with EDX detector and X-ray diffraction (XRD), respectively. The thickness of the sol–gel TiO2–ZrO2 films deposited on the stainless steel is determined by glow discharge optical emission spectrometry (GD-OES). The corrosion behavior of the stainless steel, coated by amorphous films, is evaluated in 3 wt% NaCl and 0.5 mol dm−3 HCl by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. It is found that the sol–gel TiO2–ZrO2 films with the amorphous structure, deposited by the sol–gel process, and calcined at 400 °C significantly enhance the corrosion properties of AISI 316L in both chloride media.

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On the structure alteration of crosslinkable gelatin coupled with methacrylic acid and its hydrogel

e-Polymers ◽

10.1515/epoly.2012.12.1.151 ◽

2012 ◽

Vol 12 (1) ◽

Author(s):

Xiaohong Hu ◽

Dan Li ◽

Feng Zhou ◽

Changyou Gao

Keyword(s):

Molecular Weight ◽

Triple Helix ◽

Sol Gel ◽

Average Molecular Weight ◽

Gel Permeation Chromatography ◽

Apparent Molecular Weight ◽

Small Range ◽

Scanning Calorimetry ◽

Physical Chemical ◽

Substitution Degree

AbstractPhysical structures of a crosslinkable gelatin derivative (GM) were studied in terms of alteration of apparent molecular weight, triple helix content and mechanical strength. The GM with a substitution degree (DS) of 49% and 79% was prepared by grafting mechacrylic acid (MA), which was able to form injectable hydrogel by photoinitiating polymerization. The zeta potential was increased along the increase of DS. After modification, the apparent number-average molecular weight (Mn) detected by gel permeation chromatography was decreased to about 2/3 of gelatin, while the apparent weight-average molecular weight (Mw) was changed within a small range. Differential scanning calorimetry and circular dichroism (CD) revealed that ability of triple-helix formation of GM was decreased along with the increase of DS and decrease of GM concentration. After photocrosslinking, the sol-gel transition of GM49 physical-chemical hydrogel still existed, but completely disappeared for its chemical hydrogel. The physical-chemical hydrogel showed a larger storage modulus at 20°C than at 37°C as a result of additional physical crosslinking.

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Enhanced Corrosion Protection of Epoxy/ZnO-NiO Nanocomposite Coatings on Steel

Coatings ◽

10.3390/coatings10080783 ◽

2020 ◽

Vol 10 (8) ◽

pp. 783 ◽

Cited By ~ 1

Author(s):

Muna Ibrahim ◽

Karthik Kannan ◽

Hemalatha Parangusan ◽

Shady Eldeib ◽

Omar Shehata ◽

...

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Corrosion Protection ◽

Electrochemical Impedance ◽

Sol Gel ◽

Morphological Characterization ◽

Coated Steel ◽

X Ray ◽

Edax Analysis

ZnO-NiO nanocomposite with epoxy coating on mild steel has been fabricated by the sol–gel assisted method. The synthesized sample was used to study corrosion protection. The analysis was performed by electrochemical impedance spectroscopy in 3.5% NaCl solution. The structural and morphological characterization of the metal oxide nanocomposite was carried out using XRD and SEM with Energy Dispersive Absorption X-ray (EDAX) analysis. XRD reveals the ZnO-NiO (hexagonal and cubic) structure with an average ZnO-NiO crystallite size of 26 nm. SEM/EDAX analysis of the ZnO-NiO nanocomposite confirms that the chemical composition of the samples consists of: Zn (8.96 ± 0.11 wt.%), Ni (10.53 ± 0.19 wt.%) and O (80.51 ± 3.12 wt.%). Electrochemical Impedance Spectroscopy (EIS) authenticated that the corrosion resistance has improved for the nanocomposites of ZnO-NiO coated along with epoxy on steel in comparison to that of the pure epoxy-coated steel.

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