Copper Stearate Research Articles

Facile spraying prepared superhydrophobic coating with self-cleaning, corrosion resistance, and increased buoyancy

The excellent mechanical properties and low-cost characteristics of carbon steel make it widely used in various facilities and equipment, but it is prone to corrosion, leading to performance degradation. Inspired by the superhydrophobic phenomenon in nature, in this paper, we used synthesized copper stearate (CuSA2) and polydimethylsiloxane (PDMS) with low surface energy properties to prepare superhydrophobic CuSA2/PDMS coatings on Q235 carbon steel substrates via a facile spray-coating method. The prepared superhydrophobic coating confirms micro-nano multi-level structures and low surface energy properties through wettability tests, surface morphology, and elemental analysis. Additionally, electrochemical impedance spectroscopy (EIS) results showed that the low-frequency modulus and charge transfer resistance of the coated substrate increased by three orders of magnitude compared to the bare Q235 carbon steel. The corrosion inhibition efficiency of the fabricated coating was 99.91 %, demonstrating significantly enhanced corrosion protection capabilities. Furthermore, due to the unique interface non-wetting and liquid-repellent properties of the surface, the coating also exhibited excellent self-cleaning and buoyancy-increasing characteristics, expanding the application areas of such materials significantly.

Tailoring the catalytic microenvironment of CuO with hydrophobic CuSA2 for selective CO2 electroreduction to C2+ products

Advancing the Faraday efficiency (FE) and current density of Cu catalyzed electrochemical CO2 reduction (ECR) reaction to produce C2+ products is important for its practical applications. Constructing a hydrophobic interface to regulate the local reaction environment is an effective method to improve the selectivity of C2+ products, but it is limited by the low reaction current density. In this work, we fabricated a novel hydrophobic and ECR active copper stearate (CuSA2) decorated CuO nanoparticle catalyst (CuO/CuSA2) for ECR reaction toward C2+ products. As a result, the CuO/CuSA2 catalyst achieved an FE of 61.33 % and a partial current density of 429.33 mA cm−2 for C2+ products. The CuSA2 and CuO nanoparticle cooperate very well for the formation of C2+ products. The in-situ attenuated total reflectance surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) and electrochemical adsorption experiment indicated that the hydrophobic CuSA2 regulated the local ECR reaction environment. The local ∗CO2.- and *CO adsorption were strengthened by hydrophobic CuSA2 modification while the H2O adsorption was inhibited. CuO nanoparticle promotes *CO coupling reaction and enhances C2 intermediates (*OCCOH and *OC2H5) adsorption. Hydrophobic CuSA2 and CuO nanoparticle synergistically promote the generation of C2+ products. This work provides new insights into the design of hydrophobic CO2 reduction electrocatalysts for the preparation of C2+ products.

Improving the in-situ upgrading of extra heavy oil using metal-based oil-soluble catalysts through oxidation process for enhanced oil recovery

The demand for fuel from unconventional sources is increasing all over the world, however, there are still special and strict regulations regarding the methods of enhanced oil recovery as well as the content of the oil produced, including the amount of sulfur. In-situ combustion (ISC) is an attractive thermal method to enhance oil recovery and in-situ upgrading process. In this work, copper (II) oleate and copper (II) stearate were used for the oxidation of extra heavy oil with high sulfur content in the ISC process using a self-designed porous medium thermo-effect cell (PMTEC) and visual combustion tube. Using PMTEC the catalytic performances of the synthesized oil-soluble copper (II) oleate and copper (II) stearate and kinetic parameters such as activation energy using Ozawa-Flynn-Wall method were studied. The X-ray diffraction (XRD) and high-resolution field emission scanning electron microscopy were used to examine the characteristics of in-situ synthesized CuO nanoparticles during oxidation. As shown, the presence of oil-soluble copper (II) stearate and copper (II) oleate reduced oil viscosity from 9964 to 8000 and 6090 mPa˙s, respectively. Following ISC process in porous media in the presence of copper (II) oleate, the high sulfur extra heavy oil upgraded, and its sulfur content decreased from 10.33 to 6.79%. Additionally, SARA analysis revealed that asphaltene and resin content decreased in the presence of oil-soluble catalysts. During the oxidation reaction, homogeneous catalyst decomposed into nanoparticles, and heterogeneous catalyst is distributed uniformly in porous media and played an active role in the catalytic process. It should be noticed that, these kind of oil-soluble catalysts can be novel and highly potential candidates for initiation and oxidation of extra heavy oil in order to decrease the viscosity, enhanced oil recovery and production of the upgraded oil.Graphical abstract

Study of the Structure and Properties of Steel G13 with Modifying and Organic Additives

The purpose of the study – is to determine the effect of modifying and organic additives on the structure and properties of G13 powder steel.Methods. The study of the microstructure and mechanical properties of G13 sludge with modifying and organic additives was carried out. As modifying additives were used: nano-aluminum oxide powder and nano-zirconium oxide powder. The following organic additives were used: ethylene-bis-stearomide, nickel stearate, copper stearate, manganese stearate, iron stearate. The microstructure was studied using an S-3400N electron microscope. Hardness was determined by the depth of the indentation by the Rockwell method. A hardened steel ball with a diameter of 1.56 mm was taken as an indenter. Bending tests were carried out on an MFL HUS-2010z electro-hydraulic tensile testing machine in automatic mode using an IBM PX personal computer.Results. When studying the microstructure of steel G13, it was found that the most fine-grained austenite structure is observed in steel with the following composition of the initial charge: Fe + 14.5% FeMn + 1.2% C + ZrO2 (nano). A uniform structure of austenite with small rounded pores is observed in steel G13, which has the following compositions of the initial charge: Fe + 13% FeMn + 1.3% C + 1% St.Cu; Fe + 14.5%FeMn + 1.2%C + 0.5% St.Mn (warm mix). The study of mechanical characteristics has shown that the best combination of hardness after sintering and bending strength is possessed by workpieces made from a powder mixture of composition Fe + 14.5% FeMn + 1.2% C + 0.5% St. Ni.Conclusion. The most positive effect on the structure of G13 powder steel was exerted by the modifying additive of nano-zirconium oxide powder, as well as organic additives of copper stearate and manganese stearate. The best combination of mechanical characteristics (hardness and bending strength) is exhibited by billets into which an organic additive of nickel stearate was introduced.

The construction of composite hydrogel evaporator with interfacial heating performance and its application in water treatment

To meet the needs of sewage cleaning and clean drinking water, a multifunctional photothermal device is designed in this paper, which mainly includes the non-infiltrating layer of copper stearate, bismuth tungstate and copper oxide composite hydrogel. By improving the synthesis process, sheet-like copper stearate and flower-like bismuth tungstate were prepared, realizing the load of canvas, felt and fabric, with the contact angles reaching 158º, 162º and 161º, respectively. The nonwetting layer has the performance of not only selective oil removal, but also mechanical stability. Through traditional non-infiltrating materials, dyes cannot be degraded, while with the introduction of bismuth tungstate, superhydrophobic materials are given photodegradation properties, thus solving the recovery problem of powder photocatalysts. The photodegradation stability was demonstrated via multiple photodegradation processes by calculating the reaction kinetic coefficient, with a degradation efficiency of greater than 90%. The position of valence (1.9 eV) and conduction (-0.735 eV) band of bismuth tungstate was calculated based on Mott-Schottky curve, DRS and VB-XPS. With the construction of copper oxide composite hydrogel, the mechanical stability was improved and an efficiency of 1.76 kg•m−2•h−1 was obtained. The composite hydrogel device can also be used to treat the aqueous solutions containing metal ions and dyes, which operates stably in aqueous solutions containing 3.5% NaCl without salt crystallization, thus proving the application value of the photothermal device.

Characterization and Superhydrophobic Anticorrosive Coating of AA-7475/ZrO2/Polymer Nanocomposites

An AA-7475 is coated with superhydrophobic (SH) polymer nanocomposites (PNCs), emphasizing the coating’s manufacturing, characterization, and anticorrosive qualities. Coating AA-7475 alloy with polyvinyl chloride (PVC), copper stearate (CS), and zirconium oxide (ZrO2) nanoparticles produces the desired superhydrophobic. Using an X-ray diffractometer, field-emission scanning electron microscopy, Fourier-transform infrared spectrometer, ZrO2 nanoparticles, CS, and PVC PNCs are analyzed structurally and molecularly. The atomic force microscope picture was analyzed to determine how the surface roughness affected the SH behavior reached by changing the weight percentage of ZrO2 nanoparticles from 0.6 to 3.0 wt%. PNC-5 with 3.0 wt% ZrO2 nanoparticles is used as resistance to corrosion coating for AA-7475 due to its water contact angle of 154°. In a 3.5% NaCl solution, uncoated and PNC-5-coated AA-7475 are examined using potentiodynamic polarization and electrochemical spectroscopy. PNC-5 coating reduces AA-7475 corrosion rate from 23.75 to 0.2253 mpy. In this study, we use polarization resistance, corrosion resistance efficiency, double layer capacitance, corrosion current density, and charge transfer resistance to demonstrate that the SH surface air trapping phenomena are responsible for effective corrosion resistance.

Bio-inspired hydrophobic copper stearate coating to reduce the moisture absorption of fine-grained ammonium perchlorate and improve safety and thermal decomposition performance

Inspired by the superhydrophobic phenomenon in nature, multifunctional fine-grained ammonium perchlorate (F-AP)@copper stearate (CS) core-shell structure composite particles were designed by the in-situ liquid deposition method. Scanning electron microscopy (SEM) characterization proved that raw AP was refined, and a series of in-depth characterizations proved that the core-shell structure of F-AP@CS was prepared. Due to the core-shell F-AP@CS bionic hydrophobic structure and low surface energy, when the CS content is 5%, the moisture absorption rate was reduced from 0.54% to 0.03% within 72 h, and the water contact angle was increased to 126.6°. At room temperature, the safety performance of F-AP is effectively improved because of the barrier effect and melting heat absorption of the CS shell, the impact sensitivity (H50) of F-AP@CS (wt = 5%) was increased from 27.2 cm to 54.2 cm, and the friction sensitivity was reduced from 96% to 0%. As the temperature rises, CS will decompose into CuO with extremely high catalytic activity at 267 °C, the high temperature decomposition peak of F-AP@CS (wt = 5%) was advanced from 423.3 °C to about 305.9 °C, and speculate the mechanism of CS catalyzing the decomposition of AP.

Исследование влияния органических и модифицирующих добавок на технологические свойства порошковой стали Г13

The paper considers the influence of various modifying and organic additives on the technological properties of G13 powder steel, with different mixing options. Technological properties such as fluidity, bulk density and compactibility were investigated. It has been established that the compaction of the G13 powder mixture with copper stearate and nickel stearate is the most successful. Of the considered carbon-containing components, the best compaction occurs with the introduction of pencil graphite. The best technological properties in terms of fluidity and bulk density were obtained with a powder mixture of composition Fe + 14 % FeMn + 1.1 % C + 0.2 % WC (nano). The introduction of organic additives worsens the fluidity of the mixture, but increases their density.

Constructing Superhydrophobic Surface on Copper Substrate with Dealloying-Forming and Solution-Immersion Method.

In this study, a superhydrophobic surface was constructed on a copper substrate through dealloying-forming and solution-immersion methods. The dealloying process for nanostructures on a copper surface involved the electrodeposition of zinc atoms, and the thermal alloying and chemical dealloying of zinc atoms. Then, a dealloyed copper surface was subsequently modified with low-surface-energy copper stearate to produce a superhydrophobic surface. Scanning electron microscopy, X-ray diffractometry, and Fourier transform infrared spectrometry were employed to characterize the morphological features and composition components of the surface in the fabrication process. The static contact angles of the copper surfaces were compared and evaluated based on various fabrication parameters, including electric current density, corrosive solution concentration, and nanostructures. The results indicated that a leaf-like copper stearate could be constructed through immersing a dealloyed copper plate into a 0.005 mol/L ethanol solution of stearic acid for 5 min. Nanostructures provided more attachment areas on the copper surface to facilitate the formation of copper stearate. The resulting as-prepared surface presented excellent superhydrophobic properties with a contact angle of over 156.5°, and showed the potential properties of non-sticking, self-cleaning, anti-corrosion, and stability. This study provides an efficient approach to fabricate superhydrophobic surfaces for engineering copper metals.

Catalytic combustion of heavy crude oil by oil-dispersed copper-based catalysts: Effect of different organic ligands

Oil-dispersed copper stearate has been reported to be a promising catalyst for improving in-situ oil combustion due to its good dispersibility in crude oils and the high catalytic activity of copper. This work focuses on investigating the influence of different organic ligands (stearate, oleate and decanoate) on the catalytic activity of copper-based organic salts as catalysts using porous medium thermo-effect cell (PMTEC). The kinetics of oil oxidation processes in the absence and presence of catalysts were estimated using isoconversional methods. All copper-based organic salts exhibited some catalytic activities in oil oxidation reactions, which is reflected in shifting oil oxidation process to lower temperatures and decreasing apparent activation energy. Nevertheless, the organic ligands have a significant impact on the catalytic performance of copper-based organic salts. Copper stearate and copper decanoate displayed a much higher catalytic activity than copper oleate. Copper decanoate with a shorter organic chain showed the lowest activation energy during all oxidation processes. In addition, stearic, oleic and decanoic acids were also added to oil for oxidation experiments to understand if the organic ligands themselves contribute to the promotion of oxidation reactions or not. It turned out that pure organic acids showed small effects on oil oxidation behavior in terms of temperature increase, which proves that the high catalytic activity arises from these copper-based organic salts, rather than the organic acids themselves.

Combination of Universal Chemical Deposition and Unique Liquid Etching for the Design of Superhydrophobic Aramid Paper with Bioinspired Multiscale Hierarchical Dendritic Structure.

It is urgent and significant for the further development of superhydrophobic materials to exploit a facile, low-cost, scalable, and eco-friendly method for the manufacture of superhydrophobic materials with self-cleaning, antifouling, directional transportation, and other characteristics. Herein, an outstanding superhydrophobic material composed of a flexible microconvex aramid paper substrate, micron-scale cone-shaped copper, micro-nanoscale dendritic copper oxide, and hydrophobic copper stearate film has been successfully constructed through delicate architectural design and a convenient preparation approach. Based on the microstructure evolution and composition analysis results, it is revealed that the cone-shaped copper was etched into a dendritic copper oxide structure step by step from the top to bottom and from the outside to inside in an alkaline liquid environment. Moreover, by virtue of the compositional features and structural characteristics, the constructed superhydrophobic material showcased a high contact angle (CA), low sliding angle (SA), high porosity, low surface free energy, and adhesion work. Meanwhile, the dendritic microstructure analysis, the calculation of solid-liquid interfacial tension, and the force analysis of water droplets jointly revealed the mechanism of the bounce and merged bounce of water droplets. Finally, this superhydrophobic material has the functions of self-cleaning, antifouling, and directional transportation, especially by controlling the deformation of the material to realize the transportation of water droplets in a specified direction.

Effect of copper stearate as catalysts on the performance of in-situ combustion process for heavy oil recovery and upgrading

Using copper stearate as catalysts, catalytic in-situ combustion (ISC) of heavy oil was studied by porous medium thermo-effect cell (PMTEC) and combustion tube experiments. Significant acceleration of combustion was observed in porous media in PMTEC when copper stearate was added. Copper stearate promoted fuel deposition and its combustion and made them occur easier in low temperature, thus shifting both low-temperature oxidation (LTO) and high-temperature oxidation (HTO) into lower temperatures, and even totally merge HTO into LTO in some conditions. We found that the promotion on fuel deposition by catalysts might be related to the change of H/C ratio in fuel. The improvement in the performance of ISC by copper stearate in combustion tube experiments mainly manifests in lower ignition temperature, lower H/C ratio, increased air/fuel ratio, higher oil recovery, and higher level of in-situ oil upgrading, which makes copper stearate a good candidate for catalyzing ISC in field application. • Copper stearate as catalyst improves performance of ISC process of heavy oil. • It shifts LTO and HTO into lower temperatures, and even merges HTO and LTO together. • It promotes fuel formation and combustion by changing H/C ratio. • It reduces ignition temperature and H/C ratio, and increases oil recovery. • In-situ upgrading of oil occurs in ISC and copper stearate improves it.

Chemical Inferences Drawn From Volcanic Pumice

The idea to conduct this study suggested itself amid attempts to respond to a question concerning the Kula Geopark. The question was whether the samples taken from the site could be used to teach Physical Chemistry and Nanoscience in laboratory. With this end in view, firstly the pumice samples were characterized by X-ray Fluorescence Spectroscopy, Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy analyses. Next, after observing superhydrophilic nature of the pumice with porous structure containing various metal oxides, the samples were coated with copper stearate dispersion using a spraying method. And then the wettability properties and contact angles of the copper stearate-treated samples were determined. Given the structure of the pumice samples and other findings, it was discussed which models would apply to the wettability of these samples

Mechanistic and kinetic insight into catalytic oxidation process of heavy oil in in-situ combustion process using copper (Ⅱ) stearate as oil soluble catalyst

In this study, copper (Ⅱ) stearate was proposed as oil-soluble catalysts for catalyzing heavy oil oxidation in in-situ combustion (ISC) process to improve the efficiency of ISC for heavy oil recovery. Its catalytic mechanism and kinetics were deeply investigated by joint use of TG-FTIR, autoclave experiments, FESEM-EDX, and XPS, etc., together with isoconversional kinetic methods. We find that the addition of copper (Ⅱ) stearate initiated both efficient homogenous and heterogenous catalytic oxidation/combustion process of heavy oil. In low-temperature range, copper (Ⅱ) stearate (before its full decomposition) played a homogenous catalytic role in low temperature oxidation (LTO), and in high-temperature range, in-situ formed CuO nanoparticles (after the full decomposition of copper (Ⅱ) stearate) played a heterogenous catalytic role in the formation and combustion process of fuel (coke-like residues) in fuel deposition (FD) and high temperature oxidation (HTO) stages. Specifically, the addition of copper (Ⅱ) stearate significantly reduced the values of Eα of all reaction stages (LTO, FD, and HTO), especially at the later stage of LTO, FD and the beginning of HTO (the maximum values of Eα were decreased from about 500–600 KJ/mol to 300–400 KJ/mol), decreased the energy required to overcome reaction barriers, and improved the formation rate and quality of coke-like residues, which thus promotes the formation of coke-like residues and their combustion a more continuous process. Such a superior catalytic effect makes copper (Ⅱ) stearate have a great potential in improving efficiency of ISC process for heavy oil recovery.

A sky-blue superhydrophobic coating and applications

Efforts made to efficiently fabricate traditional superhydrophobic coating have always faced limitations such as high cost, recontamination, and sophistication. An artificial superhydrophobic copper stearate (CS) polydimethylsiloxane (PDMS) coating was fabricated to achieve the transition of a water-adhesion surface to a water-repellent surface. This coating formed superhydrophobic surfaces in different types of substrates through dipping, spraying, and brushing, and demonstrated excellent water repellency, low contact angle hysteresis, and weak adhesive forces after exposure to tape-peeling cycles (VHB, 3 M), abrasion cycles, acid/alkali solutions, corrosive solutions, freezing water, and boiling water. Additionally, experiments were conducted on potential applications of the superhydrophobic coating in oil/water separation, self-cleaning, and anti-corrosion.

In situ synthesis of copper stearate/ammonium perchlorate shell–core composite for self-catalytic thermal decomposition

In this study, copper stearate (CS) was investigated as a potential catalyst for the thermal decomposition of ammonium perchlorate (AP). Copper stearate/ammonium perchlorate (CS/AP) shell–core composite was prepared by in situ synthesis and characterized to sample by SEM and EDS, it shows that CS is evenly dispersed on the surface of AP and forms a shell–core structure. Through using DSC and analyzing the thermal decomposition performance of CS/AP composite,the results show that the thermal decomposition temperature of AP decreased with the increase of catalyst content,when catalyst content is 4%, the thermal decomposition temperature of AP goes down 78.4 °C, and its catalytic effect is best. CS/AP shell–core composite provides a fresh idea for the thermal decomposition of AP.

The effect of modified Cu(II) kaolinite on interactions with rubberizing components

The interactions of modified Cu(II) kaolinite with rubberizing components, such as stearic acid (SA), zinc oxide (ZnO), sulphur (S) and benzothiazole (Btz) after heating to 150 °C cure temperature were investigated. More over the given prepared modified kaolinite was used for investigation of its effect in model rubber composites. Commercially calcined kaolinite (Kaol) was chemically treated using 0.5 M copper acetate solution in presence of NaOH solution. The modified resulting sample was designated as KCu sample. Different techniques such as Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction patterns analysis (XRD), thermogravimetry/differential thermal analysis (TG/DTA) and scanning electron microscopy (SEM) were used to characterize kaolinite and KCu samples. The different techniques (mainly FTIR an XRD) demonstrated that the copper acetate treatment of kaolinite resulted in formation of monohydrate copper hydroxy acetate complex, which influenced the clay surface. XRD pattern and FTIR spectrum of the modified KCu proved that copper acetate treatment did not affect the clay structure significantly. High-temperature X-ray diffraction patterns analysis (HTXRD) was also used for investigate the interactions of modified KCu with rubberizing components. Heating process of KCu and SA without or with ZnO caused the formation of copper stearate and zinc stearate respectively and it let to the occurrence of the stretching vibrations of the carboxyl group (νCOO−). K-Cu2(OH)3Ac·H2O complex on the clay surface influenced the mutual interaction with benzothiazole and it can be seen in IR spectra involving stretching vibrations (νCH) of aromatic ring and the stretching vibrations of functional groups ν(N=CS) and ν(C=N). Finally, for the supplementation of the results, the model rubber composites, filled with kaolinite and KCu and ranged 5, 10 and 20 phr, were prepared. The effect of modified kaolinite on the curing characteristics (minimum torque – ML, maximum torque – MH, optimal vulcanization time – t90, coefficient of vulcanization rate – Rv) and mechanical properties (tensile strength at break – TSb, elongation at break – Eb and hardness) in sulphur-cured natural rubber (NR) composites was investigated. A low viscosity of the NR compounds was achieved throughout the kaolinite and KCu fillers used. The cure time increased by KCu dosing in amount of 10 and 20 phr. The decrease of the maximum torque (MH) value indicates a lower stiffness as well as the viscosity of the mixture at the end of vulcanization. However, the mechanical properties of the vulcanizates with KCu showed significant improvement of TSb and Eb, compared with standard and mixtures with non-modified kaolinite. The modified Cu(II) form of kaolinite had positive effect on the properties of rubber compounds in amount of 5 and 10 phr.

Low-temperature combustion behavior of crude oils in porous media under air flow condition for in-situ combustion (ISC) process

A porous medium thermo-effect cell (PMTEC) was developed to fast characterize the combustion of crude oils in porous media in air flow for air injection enhanced oil recovery (EOR) process. We described how PMTEC works and employed it to investigate the combustion behavior of seven crude oils including two light oils, two medium oils, two heavy oils, and one extra heavy oil. The results showed that, except the two light oils, the others exhibited a strong low-temperature combustion (LTC) phenomenon at about 270–280 °C with a high temperature increase to approximately 700 °C and the release of CO2 and CO gaseous products. This LTC behavior was compared with the widely documented oxidation behavior in air injection process including low-temperature oxidation (LTO) and high-temperature oxidation (HTO) characterized by high-pressure differential scanning calorimetry (HP-DSC). It turned out that the LTC occurred in PMTEC was different from the LTO or HTO observed from HP-DSC experiments. In addition, this LTC can propagate in porous media with air flow, which was detected by a newly developed optical fibre technology instead of traditional thermal couples. Furthermore, the effect of copper stearate, iron stearate, nickel stearate, and cobalt stearate as oil-soluble catalysts on the LTC was investigated. Copper stearate showed the best catalytic effect. It significantly shifted onset and peak temperatures into lower temperature from 278 and 287 °C to 227 and 237 °C, respectively, exhibiting a great potential in catalyzing crude oils combustion in ISC process. The catalytic effect of these four catalysts is in turn: copper > iron > cobalt > nickel.

ZnO nanoparticles impregnated polymer composite as superhydrophobic anti-corrosive coating for Aluminium-6061 alloy

This work emphasizes the preparation, characterization and anti-corrosive behavior of super-hydrophobic (SH) polymer nanocomposite (PNC) coating developed on Al-6061 alloy. The SH nature is achieved on Al-6061 alloy by coating a mixture containing polyvinyl chloride (PVC), copper stearate (CS) and ZnO nanoparticles (Nps). The structural and molecular characterizations of ZnO Nps, CS, PVC, and PNCs are performed employing XRD, FESEM, FTIR, etc. The influence of average roughness of the surface towards the SH behavior achieved by varying the wt% of ZnO Nps from 0.5 wt% to 2.5 wt% has been assessed from the AFM images. The water contact angle of PNC incorporated with 2.5 wt% of ZnO Nps (PNC-5) exhibits 154° which is used as corrosion resistant coating for Al-6061. Potentiodynamic polarization and electrochemical impedance spectroscopic analysis are performed for bare and PNC-5 coated Al-6061 in 3.5 % NaCl as the electrolyte. The corrosion rate of Al-6061 is decreased from 23.75 mpy to 0.2253 mpy while coating PNC-5. Important parameters such as corrosion protection efficiency, corrosion current density, polarization resistance, charge transfer resistance, double layer capacitance, etc. are evaluated and found that the air trapping phenomenon of SH surface is responsible for the effective corrosion resistance behavior.

Study of hydrophobic modification of copper-coated mica and its spectrum, molecular structure and properties

This research deals with creating a hydrophobic surface by preparing a rough surface. To create a rough surface, that is to have low surface energy and properly constructed surface morphology. In order to find an environmentally friendly and simple method, we have explored two different techniques to achieve hydrophobic modification. So, the pretreated surface of copper-coated mica was respectively soaked with stearic acid and palmitic acid to obtain hydrophobicity. The results showed that the copper stearate (Cu[CH3(CH2)16COO]2 or Cu[CH3(CH2)14COO]2) or copper palmitate was successfully fabricated on the copper-coated mica. The contact angle and the angle of repose of the copper-coated mica before and after hydrophobic treatment were measured. The results showed that the contact angle of hydrophobic by stearic acid was 125.1°±0.2°, the angle of repose was 29°; the contact angle of hydrophobic by palmitic acid was 125.7°±0.1°, and the angle of repose was 37°. It can be considered that after the hydrophobic treatment of stearic acid and palmitic acid, the dispersibility and hydrophobicity of the copper-coated mica have been improved. The infrared extinction coefficient measured by the method of KBr tablet, and the hydrophobization with palmitic acid is greater than 0.23 m2/g, and the hydrophobization with stearic acid is greater than 0.12 m2/g.