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Electrochemical Impedance Spectroscopy of Hybrid Epoxy Resin Emulsion Coatings  [PDF]
Rakesh N. Patil, Brihbihari V. Sharma, Prakash A. Mahanwar
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2012, DOI: 10.4236/jmmce.2012.1110104
Abstract: A hybrid epoxy resin one pack emulsion with acrylate was synthesized for application in the field of corrosion protec- tion. Electrochemical impedance tests were applied to steel specimens coated with hybrid epoxy and tested after im- mersion in 3.5% NaCl solution at room temperature. Results taken from Nyquist and Bode plots as were analyzed by means of software provided with the instrument. Specimens were examined under scanning electron microscope shows a clear rupture and degradation in hybrid epoxy coating after prolonged exposer to salt solution.
NANOMECHANICAL PROPERTIES AND POSSIBLE APPLICATIONS OF MECHANOACTIVATED ZNO COATINGS
R. Zabels, F. Muktepavela, M. Chubarov
Latvian Journal of Physics and Technical Sciences , 2009, DOI: 10.2478/v10047-009-0012-3
Abstract: A simple and cost-effective mechanoactivated oxidation method (MAOM) has been developed for producing ZnO coatings on glass. To achieve the transparency of initially opaque mechanoactivated ZnO coatings they were annealed at the temperatures modifying the surface morphology of nanostructured coatings. Investigation of nanomechanical properties has revealed that MAOM coatings in as-obtained state have higher hardness (up to 3 GPa) as compared with bulk metallic zinc (160 MPa). In the annealed state the coatings show stabily high adhesion with glass, with the ability to form a grained structure (hardness 8-10 GPa) or a whiskers nanostructure (hardness 18-20 GPa). The Young modulus of coatings ranged from 80 to 120 GPa. The nanomechanical and optical properties were compared with those of bulk ZnO single crystal and commercial ZnO films. The optical properties of ZnO films with a whiskers structure are typical of a transparent high-quality ZnO single crystal. The coatings obtained have high electrical resistance, which decreases in response to the UV exposure. The photocurrent increases by two orders of magnitude, which is easily detectable and makes it possible to use such coatings as UV emission detectors.
Epoxy coatings electrodeposited on aluminium and modified aluminium surfaces  [PDF]
Lazarevi? Zorica ?.,Mi?kovi?-Stankovi? Vesna B.,Ka?arevi?-Popovi? Zorica M.,Dra?i? Dragutin M.
Hemijska Industrija , 2002, DOI: 10.2298/hemind0211468l
Abstract: The corrosion behaviour and thermal stability of epoxy coatings electrodeposited on modified aluminum surfaces (anodized, phosphatized and chromatized-phosphatized aluminium) were monitored during exposure to 3% NaCl solution, using electrochemical impedance spectroscopy (EIS) and thermogravimetric analysis (TGA). Better protective properties of the epoxy coatings on anodized and chromatized-phosphatized aluminum with respect to the same epoxy coatings on aluminum and phosphatized aluminum were obtained: higher values of Rp and Rct and smaller values of Cc and Cd, from EIS, and a smaller amount of absorbed water inside the coating, from TGA. On the other hand, a somewhat lower thermal stability of these coatings was obtained (smaller values of the ipdt temperature). This behavior can be explained by the less porous structure of epoxy coatings on anodized and chromatized-phosphatized aluminum, caused by a lower rate of H2 evolution and better wet ability.
Adhesion of epoxy cataphoretic coatings on Zn alloys
JELENA B. BAJAT,VESNA B. MISKOVIC–STANKOVIC,DRAGUTIN M. DRAZIC
Journal of the Serbian Chemical Society , 2007,
Abstract: One of the most important factors in corrosion prevention by protective coatings is the loss of coating adhesion under environmental influence. In this work, the adhesion of epoxy cataphoretic coatings was examined on steel and steel modified by Zn–Fe and Zn–Co alloys. The dry and wet adhesions of epoxy primers were measured by the direct pull-off standardized procedure, as well as indirectly by the NMP test. The corrosion stability of the coated samples was investigated by electrochemical impedance spectroscopy. It was shown that under dry testing conditions all the samples exhibited very good adhesion. However, different trends of adhesion loss of different protective systems during exposure to a corrosive agent (3 % NaCl solution) were observed. The lowest adhesion values were obtained for epoxy coating on the steel substrate. The change in adhesion of the epoxy coating on steel modified by Zn–Co alloy during immersion in 3 % NaCl solution for 24 days was the smallest of all the investigated samples. Electrochemical impedance measurements in 3 % NaCl solution confirmed the good protective properties of this protective system, i.e., greater values of pore resistance were obtained.
Effect of nano Al pigment on the anti corrosive performance of waterborne epoxy coatings
Effect of Nano Al Pigment on the Anticorrosive Performance of Waterborne Epoxy Coatings

Lili XUE,Likun XU,Qingfen LI,
Lili
,XUE,Likun,XU,Qingfen,LI

材料科学技术学报 , 2007,
Abstract: This paper presents the results regarding the effect of nano aluminum powder pigment concentration on the protective properties of waterborne epoxy films in 3.5 wt pct NaCl solution. The anticorrosive performance of the coatings with 0.5, 1, and 3 wt pct pigments and none pigment were investigated using electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and Raman spectroscopy techniques.The results show that adding appropriate amount of nano-aluminium powder pigment can enhance the barrier properties of the epoxy coating, which is attributed to the surface effect of nanoparticles and the compatibility of the pigment with the waterborne epoxy coatings.
Characterization of Hybrid Epoxy Nanocomposites  [PDF]
Shelly Simcha,Ana Dotan,Samuel Kenig,Hanna Dodiuk
Nanomaterials , 2012, DOI: 10.3390/nano2040348
Abstract: This study focused on the effect of Multi Wall Carbon Nanotubes (MWCNT) content and its surface treatment on thermo-mechanical properties of epoxy nanocomposites. MWCNTs were surface treated and incorporated into two epoxy systems. MWCNT's surface treatments were based on: (a) Titania coating obtained by sol-gel process and (b) a nonionic surfactant. Thermo-mechanical properties improvement was obtained following incorporation of treated MWCNT. It was noticed that small amounts of titania coated MWCNT (0.05 wt %) led to an increase in the glass transition temperature and stiffness. The best performance was achieved adding 0.3 wt % titania coated MWCNT where an increase of 10 °C in the glass transition temperature and 30% in storage modulus were obtained.
Assessment of the Erosive Wear Kinetics of Epoxy Coatings Modified with Nanofillers  [PDF]
Danuta Kotnarowska, Micha? Przerwa
Journal of Surface Engineered Materials and Advanced Technology (JSEMAT) , 2013, DOI: 10.4236/jsemat.2013.31A013
Abstract:

The paper presents results of investigation on the erosive wear kinetics of epoxy coatings modified with alumina or silica nanoparticles. Natural weathering caused a decrease of their erosive wear resistance. After a 3-year natural weathering, highest erosive wear resistance showed the epoxy coating modified with alumina nanoparticles.

Electrochemical properties and thermal stability of epoxy coatings electrodeposited on aluminium and modified aluminium surfaces
VESNA B. MISKOVIC-STANKOVIC,ZORICA Z. LAZAREVIC,ZORICA M. KACAREVIC-POPOVIC
Journal of the Serbian Chemical Society , 2001,
Abstract: The corrosion behaviour of epoxy coatings electrodeposited on aluminium, as well as on electrochemically and chemically modified aluminium were investigated during exposure to 3 % NaCl. Electrochemical impedance spectroscopy (EIS) and thermogravimetric analysis (TGA) were used for the determination of the protective properties of epoxy coatings on aluminium, anodized aluminium, phosphatized and chromatized-phosphatized aluminium. The protective properties of epoxy coatings on anodized and chromatized-phosphatized aluminium are significantly improved with respect to the same epoxy coatings on aluminium and phosphatized aluminium: higher values of the pore resitance and charge-transfer resistance, lower values of the coating capacitance, double-layer capacitance and relative permittivity (from EIS) smaller amount of absorbed water inside the coating (From TGA). On the other hand, the lower values of the ipdt temperature indicate a lower thermal stability of the epoxy coatings on anodized and chromatized-phosphatized aluminium.
EVALUATION OF PROTECTING PROPERTIES OF EPOXY COATINGS ON NAVY STEEL BY ELECTROCHEMICAL IMPEDANCE ESPECTROSCOPY
Ramírez,D.; Vera,R.; Gómez,H.; Co?ajahua,C.;
Journal of the Chilean Chemical Society , 2005, DOI: 10.4067/S0717-97072005000200010
Abstract: electrochemical impedance spectroscopy (eis), open circuit potential (o.c.p.) measurements and saline fog chamber experiments were employed to study the protective action of four epoxy coatings on navy steel immersed in artificial seawater. from eis data such as pore resistance, coating capacitance, and the use of the proper electric equivalent circuits it was possible to obtain information regarding the corrosion behavior under each coating. results have been interpreted under the assumption that it is possible to predict the lifetime of conventional paintings as compared with chemically modified coatings. after 40 days of immersion, variable results between electrochemical experiments and saline fog chamber experiments were obtained
EVALUATION OF PROTECTING PROPERTIES OF EPOXY COATINGS ON NAVY STEEL BY ELECTROCHEMICAL IMPEDANCE ESPECTROSCOPY  [cached]
D. Ramírez,R. Vera,H. Gómez,C. Co?ajahua
Journal of the Chilean Chemical Society , 2005,
Abstract: Electrochemical Impedance Spectroscopy (EIS), open circuit potential (o.c.p.) measurements and saline fog chamber experiments were employed to study the protective action of four epoxy coatings on navy steel immersed in artificial seawater. From EIS data such as pore resistance, coating capacitance, and the use of the proper electric equivalent circuits it was possible to obtain information regarding the corrosion behavior under each coating. Results have been interpreted under the assumption that it is possible to predict the lifetime of conventional paintings as compared with chemically modified coatings. After 40 days of immersion, variable results between electrochemical experiments and saline fog chamber experiments were obtained
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