Scientific Engineering of Anti-Corrosion Coating Systems based on Organic Metals (Polyaniline)

Dr. Bernhard Wessling
Ormecon Chemie GmbH & Co. KG, Ammersbek
(a subsidiary of Zipperling Kessler & Co.)

Footnotes

  1. B. Wessling, German Patent P 37 29 566.7, Zipperling Kessler & Co. (1987).

  2. D. W. DeBerry, J. Electrochem. Soc. 132, 1022 (1985).

  3. G. Mengoli, M. Munari, P. Bianco, M. Musiani, J. Appl. Polym. Sci. 26, 4247-4257, (1981).

  4. Joint Patent Application with Allied Signal, (Morristown/USA), PCT/US 93/00543

  5. a) B. Wessling, DE 43 34 628 A1, Zipperling Kessler & Co. (1993).
    b) B. Wessling, Adv. Mater. 6, No 3, 226 (1994).
    c) B. Wessling, PCT WO 95/00678, Zipperling Kessler & Co. (1993).

  6. Wei-Kang Lu, R. L. Elsenbaumer, B. Wessling, Syth. Met. 71, 2163-2166 (1995).

  7. B. Wessling, Synth. Met. 85, 1313-1318 (1997).

  8. Wei-Kang Lu, S. Basak, R.L. Elsenbaumer, "Corrosion Inhibition of Metals by Conductive Polymers", in: Handbook of Conducting polymers, T.A. Skotheim, R. Elsenbaumer, J.R. Reynolds (eds), 881-920 (M. Dekker 1998).

  9. T. Schauer, A. Joos, L. Dulog, C.D. Eisenbach, "Protection of iron with polyaniline primers against corrosion", to be published in Progress in Organic Coatings (in print).

  10. A.-M. Hugot-Le Goff, C. Palotta, J. Electrochem. Soc. 132 (11), 2805-2806 (1985); N. Boucherit, P. Delichere, S. Joiret, A.-M. Hugot-Le Goff, Mat. Sci. Forum 44&45, 51-62 (1989).

  11. in case of copper, the oxide is Cu2O (B. Wessling, J. Posdorfer, W. Strunskus, to be published)

  12. a) G. Nimtz, A. Enders, P. Marquardt, R. Pelster, B. Wessling, Synth. Met. 45, 197-201 (1991)
    b) G.Nimtz, R. Pelster, B. Wessling, Physical Review B, 49 (18), 12718-12723 (1994).

  13. a) C.K. Subramaniam, A.B. Kaiser, P.W. Gilberd, B. Wessling, Journal of Polym. Sci. Part B: Polym. Phys. 31, 1425-1430, (1993)
    b) C.K. Subramaniam, A.B. Kaiser, P.W. Gilberd, B. Wessling, Synth. Met. 69, 197-200 (1995)
    c) C.K. Subramaniam, A.B. Kaiser, P.W. Gilberd, C.-J. Liu, B. Wessling, Solid State Commun. 97 (3), 235-238 (1996).

  14. our own unpublished measurements

  15. Ormecon Chemie, Ammersbek (Germany) technical information (previously published by Zipperling Kessler & Co., Ormecon’s holding)

  16. Test Report of DECHEMA (D-Frankfurt), Title: Tests on "passivated" steel specimens; Scope of order: Corrosion test programme for crevice and pitting corrosion and galvanic corrosion of various pre-treated steel specimens (6/1994).

  17. B. Wessling, together with S. Schröder, S. Gleeson, H. Merkle and F. Baron, Materials and Corrosion 47, 439 (1996).

  18. note: our Organic Metal is the first metal which can be reduced (2 e- and 2 H+ per dimer)

  19. the structures are comparable to those described in:

    B. Wessling, Polym Eng. & Sci., 31 (16), 1200-1206 (1991).

    The thermodynamic reasons for the structure formation are explained by non-equilibrium thermodynamics, cf.:

    a) B. Wessling, Synth. Met. 45, 119-149 (1991).
    b) B. Wessling, Zeitschrift f. Physikalische Chemie 191, 119-135 (1995).

    For more recent overviews about flocculation in dispersions, their thermodynamical basis and relationship with properties see:

    a) B. Wessling in: Handbook of Conducting Polymers, Skotheim, Elsenbaumer, Reynolds (eds), 467-530 (M. Dekker 1998).
    b) B. Wessling in: Handbook of Organic Conductive Molecules and Polymers, Hari Singh Nalwa (ed.), vol. 3, 497-632, (Wiley 1997).

  20. "PANDA", a product developed by Monsanto, cf. P. Kinlen, D. Silverman, C. Jeffreys, Synth. Met. 85, 1327-1332 (1997).

  21. in fact, CORRPASSIVTM generally outperforms zinc-rich epoxies, and this even at significantly lower coating thickness (20 µm vs. 60-80 µm).

  22. we have also tested PANDA in direct comparison with CORRPASSIV and standard corrosion prevention coatings and found no anti-corrosion effect at all, a fact which was later confirmed by other independent studies, too.

  23. cf B. Wessling: "Conductive Polymer / Solvent Systems: Solutions or Dispersions?"

    a) Proceedings of SEAM (Search for Electroactive Materials), workshop at Brooklyn Polytechnic Institute, N.Y., Dec. 1996,
    b)Proceedings of 3rd BPS (Bayreuth Polymer & Materials Research Symposion), Bayreuth (Germany) April 1997,
    manuscript to be downloaded from internet: http://www.ormecon.de/Research/soludisp.
    See especially ch. 2.5 and 3 and Fig. 13.

  24. D.A. Wroblewski, B.C. Bencewicz, K.G. Thompson, C.J. Bryan, Polym. Prepr. 35 (1), 265 (1994).

  25. a) R. Racicot, T. Brown, S.C. Yang, Synth. Met. 85, 1263 (1997).
    b) M. Fahlmann, S. Jasty, A. Epstein, Synth. Met. 85, 1323-1326 (1997).

  26. such products are commercially available under CORRPASSIV tradename (Ormecon Chemie); more developmental products are available under certain agreements, as well as predispersions suitable for primer formulation work; the whole technology is protected by international patents (mainly as cited in [1] and [5a and c], additional necessary technological aspects being protected in other patents; full patent list available from author

  27. there are several incompatibility phenomena which may occur: (a) insufficient wetting or interlayer adhesion (b) insufficient curing of the top coat due to the chemical properties of the primer, as the primer contains an acid salt and provides an acid environment, which cannot be tolerated by all top coat systems

  28. later developments might be offered as single coat systems, comprising all 3 necessary effects (ennobling, passivation, sealing) together

  29. internal test requirements: (1) potential shift comparable as described in [5b] (2) similar or better corrosion performance - in blistering, corrosion in scratch, underfilm corrosion and its progression - compared with a zinc-rich epoxy primer + epoxy top coat (as used in [11])

  30. T. Schauer, A. Joos and E. Praschak, in Investigation of the compatibility of selected top coats with primer 900226/32, test report on behalf of Zipperling Kessler & Co. (Ormecon Chemie), Forschungsinstitut für Pigmente und Lacke e.V., Stuttgart, (1996).

  31. Test performed by Research Institute for Pigments and Paints, Stuttgart (Germany), Title: Filiform corrosion on aluminum: Polyaniline primer offers superior protection.

  32. Cf. [9], S.1 and Fig. 5.

  33. B. Wessling, J. Posdorfer, "Corrosion prevention with an Organic Metal (Polyaniline): surface ennobling, passivation, corrosion test results", Procedings Electrochem. Soc. (Dourdan), Sept. 1997

  34. technical information "CORRPASSIVTM Primers" Ormecon Chemie

  35. unpublished results

  36. cf. "Industrial reference objects" / Reports Ormecon Chemie, here: "Skippers CORRPASSIV" and "Protection of cattle barn steel plates"

  37. M. Stratmann, H. Streckel and R. Feser, Corros. Sci. 32, 467 (1991).

  38. M. Stratmann, R. Feser and A. Leng, farbe und lacke 100, 2, 93 (1994).

  39. Technical Information UBM

  40. we prefer to measure the corrosion potential and its shift during ennobling with the open circuit potential technique as described in 4.1, which is more realistic in relation to the corrosion process

  41. G. S. Popkirov, R.N. Schindler, Electrochim. Acta 39, 2025 (1994); we are now using a principally comparable, but more modern and commercially useful apparatus

  42. U. Rammelt and G. Reinhard, farbe und lacke 98, 4, 261 (1992).

  43. CORRPASSIVTM 4900, 4901, 4902, 4903, 4904, 4905, 4906, 4003, Skipper’s CORRPASSIVTM, cf. Technical Information Ormecon Chemie, printed versions or Internet http://www.ormecon.de/Products

  44. Ormecon Chemie, Industrial Reference object reports; printed information or Internet http://www.ormecon.de/corrprax

  45. cf. Internal test report "CORRPASSIVTM compared with high-grade standard systems".



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