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Journal of Coatings Technology

, Volume 75, Issue 941, pp 37–50 | Cite as

Relating laboratory and outdoor exposure of coatings: IV. Mode and mechanism for hydrolytic degradation of acrylic-melamine coatings exposed to water vapor in the absence of UV light

  • Tinh Nguyen
  • Jon Martin
  • Eric Byrd
Article

Abstract

Acrylic-melamine coatings are known to be susceptible to hydrolysis when exposed to water or humid environments. The mode and specific pathways for hydrolytic degradation of acrylic-melamine coatings exposed to water vapor in the absence of ultraviolet light are presented. Samples of a partially methylated melamine-acrylic coating applied to CaF2 substrates were subjected to five different relative humidity levels ranging from approximately 0 to 90% at 50°C. Coating degradation was measured with transmission Fourier transform infrared spectroscopy (FTIR) and tapping mode atomic force microscopy (AFM). In humid environments, partially methylated melamine-acrylic coatings undergo hydrolysis readily, causing considerable material loss and formation of mainly primary amines and carboxylic acids. The rate of hydrolysis increases with increasing RH. Hydrolytic degradation of acrylic-melamine coatings is an inhomogeneous process in which pits form, deepen, and enlarge with exposure. Such localized degradation mode suggests that hydrolysis of this material is an autocatalytic progression where acidic degradation products formed in the pits catalyze and accelerate the hydrolysis reactions.

Keywords

Atomic Force Microscopy Image Melamine Primary Amine Hydrolytic Degradation Outdoor Exposure 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. (1).
    Schmitz, P.J., Holubka, J.W., and Xu, L., “Acid Etch of Automotive Clearcoats II. Comparison of Degradation Chemistry in Laboratory and Field Testing,”Journal of Coatings Technology,72, No. 902, 53 (2000).CrossRefGoogle Scholar
  2. (2).
    Holubka, J.W., Schmitz, P.J., and Xu, L.-F., “Mechanism for Environmental Etch of Acrylic Melamine-Based Automotive Clearcoats: Identification of Degradation Products,”Journal of Coatings Technology,72, No. 904, 39 (2000).Google Scholar
  3. (3).
    Schulz, U., Trubiroha, P., Schernau, U., and Baumgart, H.,Prog. Org. Coat., 40, 151 (2000).CrossRefGoogle Scholar
  4. (4).
    Rogers, W.R., Garner, D.P., and Cheever, G.D., “Study of the Attack of Acidic Solutions on Melamine-Acrylic Basecoat/Clearcoat Paint Systems,”Journal of Coatings Technology,70, No 877, 83 (1998).CrossRefGoogle Scholar
  5. (5).
    Wernstäh, K.L.,Polym. Deg. Stab., 54, 57 (1996).CrossRefGoogle Scholar
  6. (6).
    English, A.D. and Spinelli, J.J., “Degradation Chemistry of Primary Crosslinks in High Solids Enamel Finishes: Solar Assisted Hydrolysis,”Journal of Coatings Technology,56, No. 711, 43 (1984).Google Scholar
  7. (7).
    Bauer, D.R. and Briggs, L.M., inCharacterization of Highly Crosslinked Polymers, Labana, S.S. and Dickie, R.A. (Eds.),ACS Symposium Series 243, American Chemical Society, Washington, D.C., p. 271, 1983.CrossRefGoogle Scholar
  8. (8).
    Bauer, D. and Mielewski, D.F.,Polym. Deg. Stab., 40, 349 (1993).CrossRefGoogle Scholar
  9. (9).
    Gerlock, J.L., Van Oene, H., and Bauer, D.,Euro. Polym. J., 19, 11 (1983).CrossRefGoogle Scholar
  10. (10).
    Gerlock, J.L., Dean, M.J., Korniski, T.J., and Bauer, D.R.,Ind. Eng. Chem. Prod. Res. Dev., 25, 449 (1986).CrossRefGoogle Scholar
  11. (11).
    Nguyen, T., Martin, J., Byrd, E., and Embree, N., “Relating Laboratory and Outdoor Exposure of Coatings: II. Effects of Relative Humidity on Photodegradation and the Apparent Quantum Yield of Acrylic-Melamine Coatings,”Journal of Coatings Technology,74, No. 932, 65 (2002).CrossRefGoogle Scholar
  12. (12).
    Nguyen, T., Martin, J.W., Byrd, E., and Embree, N.,Polym. Deg. Stab., 77, 1 (2002).CrossRefGoogle Scholar
  13. (13).
    Bauer, D.R.,J. Appl. Polym. Sci., 27, 3651 (1982).CrossRefGoogle Scholar
  14. (14).
    Berge, A., Gudmunsen, S., and Ulgelstad, J.,Eur. Polym. J., 5, 171 (1969).CrossRefGoogle Scholar
  15. (15).
    Berge, A., Kvaeven, and Ugelstad, J.,Eur. Polym. J., 6, 981 (1970).CrossRefGoogle Scholar
  16. (16).
    Rancourt, J.D.,Optical Thin Films, User’s Handbook, McGraw-Hill, New York, Chap. 6, p. 183, 1987.Google Scholar
  17. (17).
    Martin, J.W., Nguyen, T., Byrd, E., Embree, N., and Dickens, B.,Polym. Deg. Stab., 75, 193 (2002).CrossRefGoogle Scholar
  18. (18).
    Magonov, S.N. and Heaton, M.G.,Am. Laboratory, 30, May (1998).Google Scholar
  19. (19).
    VanLandingham, M., Nguyen, T., Byrd, E., and Martin, J.W., “On the Use of the Atomic Force Microscopy to Monitor Physical Degradation of Polymeric Coating Surfaces,”Journal of Coatings Technology,73, No. 923, 43 (2001).CrossRefGoogle Scholar
  20. (20).
    Weast, R. (Ed.),Handbook of Chemistry and Physics, CRC Press, 53rd ed., p. D 148, 1972.Google Scholar
  21. (21).
    Adamson, A.W.,Physical Chemistry of Surfaces, 2nd ed., Interscience, New York, pp. 584–589, 1967.Google Scholar
  22. (22).
    Barrie, J.A. and Machin, D.,Trans Faraday Soc., 67, 244 (1971).CrossRefGoogle Scholar
  23. (23).
    Toprak, C., Agar, J.N., and Falk, M.,J. Chem. Soc. Faraday, 75, 803 (1979).CrossRefGoogle Scholar
  24. (24).
    Barrie, J.A., inDiffusion in Polymers, Crank, J. and Park, G.S. (Eds.), Academic Press, New York, pp. 259–308, 1968.Google Scholar
  25. (25).
    VanLandingham, M.R., Eduljee, R.F., and Gillespie, J.W., Jr.,J. Appl. Polym. Sci., 71, 669 (1999).Google Scholar
  26. (26).
    Magonov, S.N., Elings, V.B., and Papkov, V.S.,Polymer, 38, 297 (1997).CrossRefGoogle Scholar
  27. (27).
    Sauer, B.B., McLean, R.S., and Thomas, R.R.,Langmuir, 14, 3045 (1998).CrossRefGoogle Scholar
  28. (28).
    Giraud, M., Nguyen, T., Gu, X., and VanLandingham, M.,Proc. Adhesion Society Meeting, Emerson, J.A. (Ed.), p. 260, 2001.Google Scholar
  29. (29).
    Gu, X., Raghavan, D., Nguyen, T., and VanLandingham, M.,Polym. Deg. Stab., 74, 139 (2001).CrossRefGoogle Scholar
  30. (30).
    Nguyen, T., Gu., X., VanLandingham, M., Giraud, M., Dutruc-Rosset, R., Ryntz, R., and Nguyen, D.,Proc. Adhesion Society Meeting, Emerson, J.A. (Ed.), p. 68, 2001.Google Scholar
  31. (31).
    Hearn, M.J., Ratner, B.D., and Briggs, D.,Macromolecules, 21, 2950 (1988).CrossRefADSGoogle Scholar
  32. (32).
    Yoon, S.C., Ratner, B.D., Iván, B., and Kennedy, J.P.,Macromolecules, 27, 1548 (1994).CrossRefADSGoogle Scholar
  33. (33).
    Shakesheff, K.M., Evora, C., Soriano, I., and Langer, R.,J. Colloid Interface Sci., 185, 538 (1996).CrossRefGoogle Scholar
  34. (34).
    Chen, X., McGurk, S.L., Davies, M.C., Roberts, C.J., Shakesheff, K.M., Tendler, S.J.B., and Williams, P.M.,Macromolecules, 31, 2278 (1998).CrossRefADSGoogle Scholar
  35. (35).
    Pienka, Z., Oike, H., and Tezuka, Y.,Langmuir, 15, 3197 (1999).CrossRefGoogle Scholar
  36. (36).
    Gu, X., Nguyen, T., Sung, L., and Jean, J.,Proc. of the Federation of Societies for Coatings Technology Annual Meeting Program, New Orleans, LA, November, 2002.Google Scholar
  37. (37).
    Chang, T.T.,Prog. Org. Coat., 29, 45 (1996).CrossRefGoogle Scholar
  38. (38).
    Blank, W.J. and Hensley, W.L., “Use of Amino Crosslinking Agents in Water-Based Coatings,”Journal of Paint Technology,46, No. 593, 56 (1974).Google Scholar
  39. (39).
    Bauer, D. and Dickie, R.,J. Appl. Polym. Sci., 18, 2014 (1980).Google Scholar
  40. (40).
    Larkin, P.J., Makowski, M.P., Colthup, N.B., and Flood, L.A.,Vibrational Spectros., 17, 53 (1998).CrossRefGoogle Scholar
  41. (41).
    Colthup, N.B., Daly, L.H., and Wiberley, S.E.,Introduction to Infrared and Raman Spectroscopy, 3rd ed., Academic Press, New York, p. 439, 1990.Google Scholar
  42. (42).
    Leadley, S.R., Shakesheff, K.M., et al.,Biomaterials, 19, 1353 (1998).PubMedCrossRefGoogle Scholar
  43. (43).
    Gopferich, A. and Langer, R.,J. Polym. Sci., Part A. Polym. Chem., 31, 245 (1993).CrossRefGoogle Scholar
  44. (44).
    Nguyen, T., Hubbard, J.B., and Pommersheim, J.M., “Unified Model for the Degradation of Organic Coatings on Steel in a Neutral Electrolyte,”Journal of Coatings Technology,68, No. 855, 45 (1996).Google Scholar
  45. (45).
    Karyakina, M.I. and Kuzmak, A.E.,Prog. Org. Coat., 18, 325 (1990).CrossRefGoogle Scholar
  46. (46).
    Bascom, W.D.,J. Adhesion, 2, 168 (1970).CrossRefGoogle Scholar
  47. (47).
    Cuthrell, R.E.,J. Appl. Polym. Sci., 12, 1263 (1968).CrossRefGoogle Scholar
  48. (48).
    Erath, E.H. and Robinson, M.,Proc. Am. Chem. Soc. Meeting, Organic Coatings and Plastics Division, 23, 395 (1963).Google Scholar
  49. (49).
    Racich, J.L. and Koutsky, J.E., inChemistry and Properties of Crosslinked Polymers, Labana, S.S. (Ed.), Academic Press, p. 303, 1977.Google Scholar
  50. (50).
    Kontou, E., Spathis, G., and Theocaris, P.S.,J. Polymer Sci., Polym. Chem., 23, 1493 (1985).CrossRefGoogle Scholar
  51. (51).
    Gu, X., Nguyen, T., VanLandingham, M., and Raghavan, D.,Proc. Adhesion Society Meeting, Orlando, pp. 537–539, February 2002.Google Scholar
  52. (52).
    Fischer, M. and Tran, C.D.,Anal. Chem., 71, 953 (1999).PubMedCrossRefGoogle Scholar
  53. (53).
    Mayne, J.E.O. and Scantlebury, J.D.,Br. Polymer, 2, 240 (1970).CrossRefGoogle Scholar
  54. (54).
    Mayne, J.E.O. and Mills, D.J.,J. Oil & Colour Chemists’ Assoc., 58, 155 (1975).Google Scholar
  55. (55).
    Mills, D.J. and Mayne, J.E.O., inCorrosion Control by Organic Coatings, H. Leiheiser, Jr. (Ed.), National Association of Corrosion Engineers, Houston, TX, p. 12; and references therein, 1981.Google Scholar
  56. (56).
    Fernandez-Prini, R. and Corti, H., “Epoxy Coal Tar Films: Membrane Properties and Film Deterioration,”Journal of Coatings Technology,49, No. 632, 62 (1977).Google Scholar
  57. (57).
    Corti, H., Fernandez, P.R., and Gomez, D.,Prog. Org. Coat., 10, 5 (1982).CrossRefGoogle Scholar
  58. (58).
    Wu, C.L., Zhou, X.J., and Tan, Y.J.,Prog. Org. Coat., 25, 379 (1995).CrossRefGoogle Scholar
  59. (59).
    Walker, P.,Official Digest,37, No. 491, 1561 (1965).Google Scholar
  60. (60).
    Raghavan, D., Gu, X., Van Landingham, M., and Nguyen, T.,J. Polym. Sci., Polymer Physics, 39, 1460 (2001).CrossRefGoogle Scholar
  61. (61).
    Richard, J. Mignaud, C., and Wong, K.,Polym. Inter., 30, 431 (1993).CrossRefGoogle Scholar
  62. (62).
    Tesuka, Y., Nobe, S., and Shiomi, T.,Macromolecules, 28, 8251 (1995).CrossRefADSGoogle Scholar
  63. (63).
    Nguyen, T.H., Himmelstein, K.J., and Higuchi, T.,J. Controlled Rel. 4, 9 (1986).CrossRefGoogle Scholar
  64. (64).
    Streitwieser, D. Jr. and Heatcock, C.H.,Introduction to Organic Chemistry, 2nd ed., Macmillan Publishing, New York, p. 399, 1981.Google Scholar
  65. (65).
    Ibid, p. 367.Google Scholar

Copyright information

© Springer Science+Business Media 2003

Authors and Affiliations

  • Tinh Nguyen
    • 1
  • Jon Martin
    • 1
  • Eric Byrd
    • 1
  1. 1.National Institute of Standards and TechnologyUSA

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