Journal of Coatings Technology

, Volume 71, Issue 894, pp 49–60 | Cite as

Cure of secondary carbamate groups by melamine-formaldehyde resins

  • H. P. Higginbottom
  • G. R. Bowers
  • P. E. Ferrell
  • L. W. Hill
Technical Articles

Abstract

Melamine-formaldehyde (MF) resins have been used as crosslinkers for hydroxyl-functional coreactants in thermoset coatings for about 60 years. Crosslink densities of films prepared from oligomeric urethane polyols suggested that the methoxymethyl groups of MF resins could react with urethane groups (i.e., secondary carbamate groups) as well as reacting with hydroxyl groups. Co-reactants that contain secondary carbamate groups and no hydroxyl groups have been prepared with several types of backbone structures. Cure of such co-reactants by MF resins has been studied using a gradient oven with determination of impact resistance, solvent resistance, and hardness. Several formulations from these cure profile sets have been selected for crosslink density determinations by dynamic mechanical analysis (DMA). Crosslink densities of cured films are consistent with complete conversion of secondary carbamate groups at temperatures only slightly higher than those used for cure of hydroxyl groups. The -OH groups on certain acrylic polyols were converted to secondary carbamate groups. The original acrylic and the converted acrylic were both cured with MF resins. Acid resistance was much better for films prepared from the acrylic that contained secondary carbamate groups.

Keywords

Polyol Carbamate Melamine Dynamic Mechanical Analysis Methyl Ethyl Ketone 
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.
This is a preview of subscription content, log in to check access.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. (1).
    Wicks, Z.W., Jr., Jones, F.N., and Pappas, S.P.,Organic Coatings Science and Technology, Vol. 1, Wiley-Interscience, New York, p. 83, 1992.Google Scholar
  2. (2).
    Santer, J.O., “Etherified Amino Resins: Synthesis and Reactions in Surface Coatings Applications,”Prog. Org. Coat., 12, 309 (1984).CrossRefGoogle Scholar
  3. (3).
    Blank, W.J., “Melamine Formaldehyde Networks with Improved Chemical Resistance,”Proc. ACS PMSE, 77, 391 (1997).Google Scholar
  4. (4).
    Gregorovich, B.V. and Hazan, I., “Environmental Etch Performance, and Scratch and Mar of Automotive Clearcoats,”Prog. Org. Coat., 24, 131 (1994).CrossRefGoogle Scholar
  5. (5).
    Gardon, J.L., “Polyurethane Polyols: Ester-bond Free Resins for High Solids Coatings,”Journal of Coatings Technology,65, No. 819, 25 (1993).Google Scholar
  6. (6).
    Walker, F.H. and Gardon, J.L. (to Akzo Nobel Coatings, Inc.), U.S. Patent 5,130,405 (July 14, 1992).Google Scholar
  7. (7).
    Yahkind, A.L., Wagstaff, I., and Walker, F.H., “Polyurethane Polyols and Coatings Thereof Having Reduced Viscosity,” Patent Application by Akzo Nobel N.V., WO 96/40813 (1996).Google Scholar
  8. (8).
    Rehfuss, J.W. and St. Aubin, D.L. (to BASF Corp.), U.S. Patent 5,356,669 (October 18, 1994).Google Scholar
  9. (9).
    Swarup, S., McCollum, G.J., Singer, D.L., Olson, K.G., Stefko, S.T., and Mayo, M.A., Internat. Appl. No. PCT/US93/10172 (WO 94/10211) (PPG Industries,) (Oct. 25, 1993).Google Scholar
  10. (10).
    Ojunga-Andrew, M., Higginbottom, H.P. and Hill, L.W., “High Solids Coatings Based on a Novel Triisocyanate,”Proc. 22nd Waterborne, High-Solids, & Powder Coatings Symp., New Orleans, LA, 200, 1995.Google Scholar
  11. (11).
    Higginbottom, H.P., Bowers, R. G., Hill, L.W., and Courtier, J.F., “Coating Systems Based on Tricarbamate Crosslinkers Derived from Triaminononane,”Proc. 23rd Internat. Conf. on Organic Coat. Sci. and Technol., Athens, Greece, July 7–11, 1997.Google Scholar
  12. (12).
    Hill, L.W., “Dynamic Mechanical and Tensile Properties,” inPaint and Coatings Testing Manual, Ch. 46, pp. 534–546, Koleske, J.V., (Ed.), Fourteenth Edition of Gardner-Sward Handbook, ASTM, Philadelphia, PA, 1995.Google Scholar
  13. (13).
    Personal communication, Solutia Inc.; Wilson, R.C., Krejsa, M.R., Higginbottom, H.P., and Hill, L.W.Google Scholar
  14. (14).
    Chu, G. and Jones, F.N., “Low-Temperature Curing Higher-Solids Polyester Coatings with Melamine-Formaldehyde Resin Crosslinkers,”Journal of Coatings Technology,65, No. 819, 43 (1993).Google Scholar
  15. (15).
    Wicks, Z.W., Jr., Jones, F.N., and Pappas, S.P.,op. Cit.,, p. 89. 1992Google Scholar
  16. (16).
    Haseebuddin, S., Raju, K.V.S.N., and Yaseen, M., “Crosslink Density and Cure Window of Oligourethane Diol/Melamine High-Solids Coatings,”Journal of Coatings Technology,70, No. 879, 35 (1998).CrossRefGoogle Scholar
  17. (17).
    Satguru, R., McMahon, J., Padget, J.C., and Coogan, R.G., “Aqueous Polyurethanes—Polymer Colloids with Unusual Colloidal, Morphological, and Application Characteristics,”Journal of Coatings Technology,66, No. 830, 47 (1994).Google Scholar
  18. (18).
    Rynders, R.M., Hegedus, C.R. and Gilicinski, A.G., “Characterization of Particle Coalescence in Waterborne Coatings Using Atomic Force Microscopy,”Journal of Coatings Technology,67, No. 845, 59 (1995).Google Scholar
  19. (19).
    Hegedus, C.R. and Kloiber, K.A., “Acrylic-Polyurethane Dispersions: Structure and Properties in Industrial Coatings,”Proc. 21st Waterborne, Higher Solids, & Powder Coating Symp., New Orleans, LA, 144, February 9–11, 1994.Google Scholar
  20. (20).
    Blank, W.J. and Tramontano, V.J., “Properties of Crosslinked Polyurethane Dispersions,”Prog. Org. Coat., 27, 1 (1996).CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media 1999

Authors and Affiliations

  • H. P. Higginbottom
    • 1
  • G. R. Bowers
    • 1
  • P. E. Ferrell
    • 1
  • L. W. Hill
    • 1
  1. 1.Solutia Inc.USA

Personalised recommendations