Abstract
Thermosetting and photosetting acrylate polymers have been tested for their resistance to accelerated weathering. The chemical changes occurring both upon curing and upon photoaging have been followed by infrared spectroscopy. In the photodegraded polymers some functional groups are lost (ether, amide, CH groups) and oxidation products are formed (carbonyl and hydroxyl groups). The UV-cured polyurethane-acrylate coatings were found to be more resistant to accelerated weathering than the melamine/acrylate thermosets currently used as automotive finishes. The light stability of both thermoset and photoset acrylate clearcoats was substantially increased by the addition of a hydroxy-phenyltriazine UV-absorber and a HALS radical scavenger. The weathering resistance of painted metallic panels has been markedly enhanced by means of properly stabilized UV-cured acrylic coatings.
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References
Schmid, E.V.,Exterior Durability of Organic Coatings, FMJ Intern. Publ. Lin. Redhill, Surrey, 1988.
Valet, A.,Light Stabilizers for Paints, Vincentz Verlag, Hannover, 1997.
Bauer, D.R., Gerlock, J.L., Mielewski, D.F., Papute Peck, M.C., and Carter, R.O., III “Photodegradation and Photostabilization of Urethane Crosslinked Coatings,”Ind. Eng. Chem. Res., 30, 2482 (1991).
Bauer, D.R., Mielewski, D.F., and Gerlock, J.L., “Photooxidation Kinetics in Crosslinked Polymer Coatings,”Polym. Degr. Stab., 38, 57 (1992).
Dupuie, J.L., Weber, W.H., Scholl, D.J., and Gerlock, J.L., “Clearcoat Analysis in Isolated and Multi-Layer Paint Systems by Confocal Raman Microscopy,”Polym. Degr. Stab., 57, 229 (1997).
Decker, C., Moussa, K., and Bendaikha, T., “Photodegradation of UV-Cured Coatings II.- Polyurethane-Acrylate Networks,”J. Polym. Sci., A: Polym. Chem., 29, 739–747 (1991).
Valet, A., “Light Stabilization of Radiation Cured Coatings,”Polym. Paint Col. J, 182, 406 (1992) and 185, 31 (1995).
Decker, C. and Biry, S., “Light Stabilization of Polymers by Radiation-Cured Acrylic Coatings,”Prog. Org. Coat., 29, 81 (1996).
Decker, C. and Zahouily, K., “Light-Stabilization of Polymeric Materials by Grafted UV-Cured Coatings,”J. Polym. Sci., Polym. Chem. Ed., 36, 2571 (1998).
Valet, A., “Outdoor Applications of UV-Curable Clearcoats. A Real Alternative to Thermally Cured Clearcoats,”Prog. Org. Coat., 35, 223 (1999).
Fischer, W. and Meier-Westhues, U., “New Alternatives for UV-Curing Clearcoats Based on Urethane Acrylate Chemistry,”Proc. RadTech Conf., p. 179, Berlin, 1999.
Nichols, M., Gerlock, J.L., and Smith, C.A., “Rates of Photooxidation Induced Crosslinking and Chain Scission in Thermoset Polymer Coatings,”Polym. Degr. Stab., 56, 81 (1997).
Decker, C. and Zahouily, K., “Photodegradation and Photooxidation of Thermoset and UV-Cured Acrylate Polymers,”Polym. Degr. Stab., 64, 293 (1999).
Decker, C., Biry, S., and Zahouily, K., “Photostabilisation of Organic Coatings,”Polym. Degr. Stab., 49, 11 (1995).
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Département de Photochimie Générade (UMR-CNRS No. 7525), 3, rue Werner - 68200 Mulhouse (France).
Additives Division, BU Imaging and Coating Additives, CH-4002 Basle, Switzerland.
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Decker, C., Zahouily, K. & Valet, A. Weathering performance of thermoset and photoset acrylate coatings. Journal of Coatings Technology 74, 87–92 (2002). https://doi.org/10.1007/BF02720154
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DOI: https://doi.org/10.1007/BF02720154