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peter spellane

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peter spellane

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    6. The corrosion of metals Metals are unstable in oxygen; all metals form oxide. The kinetics of metal oxidation is often determined by the adhesion and integrity of the metal oxide skin that can form on metals. Steel, aluminum, titanium, and copper are examples of such active-passive metals. A metal-oxide enhancer coating is a smart coating.

    7. Automotive (steel)

    8. Infrastructure detecting metal corrosion in embedded or inaccessible structures

    9. Current practice in metal protection Barrier coatings, stable polymer coatings that prevent oxidants from from contacting metal Cathodic coatings, rich primer paints that comprise sacrificial zinc or aluminum in electrical contact with substrate metal Inhibitive coatings, primer paints that typically comprise SrCrO4 that forms an adherent, passivating metal oxide Metal pretreatments, phosphates, chromates, oxides, prolong the life of barrier coatings through better adhesion

    14. B. Wessling, Advanced Materials 1994 6, 226 and W-K Lu, R. Elsenbaumer, and B. Wessling, Synthetic Metals 1995 71, 2163 Passivation of metals by coating with polyaniline, corrosion potential shift and morphological changes Polyaniline, applied as a dispersion or in lacquers, was coated on iron, stainless steel, and copper metals. Metals coated with polyaniline dispersions showed enhanced passivity: more positive open circuit potentials and lower current densities at anodic bias. Potentiodynamic polarization provide evidence of enhanced passivity.

    15. Protonic “doping” of polyaniline: the 2-step formation of a bipolaron

    19. Aluminum deposited on poly(3-octylthiophene) W. R. Salanek, Rep. Prog. Phys. 1991, 54, 1215 Aluminum metal near the metal-polymer interface is electron deficient.

    20. XPS data indicating charge transfer between polyaniline and steel M. Fahlman, X. Crispin, J. A. O. Smallfield, R. Lazzaroni, J. L. Bredas, S. Li., Y. Wei, and A. J. Epstein, in Electroactive polymers for corrosion control, 2003, American Chemical Society, P. Zarras, J. Stenger-Smith, Y. Wei, eds. Iron vapor deposited on PANI-EB shows higher energy Fe(2p) photoelectrons; changes in N(1s) photoelectron line shapes. B. Beard and P. Spellane, Chem. Mater. 1997, 9, 1949: PANI-EB coated on CRS substrate: changes in N(1s) photoelectron spectra consistent with reduction of PANI-EB to PANI-LEB

    27. Polyaniline (LEB) and poly(2,6-dimethylphenylene ether)

    31. ASTM B-117 data for PPE-coated aluminum alloy

    44. Stop here

    46. US markets for coatings that protect metals From costofcorrosion.com September 2004, citing US Dept of Commerce Bureau of Census  Protective Coatings Sold in the United States in 1997   Organic coating material sold 1.47 billion gallons $16.56 billion (5.56 billion liters)   architectural coatings product OEM coatings special purpose coatings miscellaneous paint products   Material for “corrosion coatings” 0.56 billion gallons $6.7 billion (2.12 billion liters) (Anti-corrosion materials costs are from 4 to 20% of the total cost of application.) 

    47. Molecular structures of ICPs

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