Document Type : Wood Modification and Wood Preservation

Authors

1 MSc Graduated in Wood Preservation and Modification, Gorgan University of Agricultural Sciences and Natural Resources. Gorgan, Iran

2 Assistant Prof., Department of Wood Engineering and Technology, Gorgan University of Agricultural Sciences and Natural Resources. Gorgan, Iran

3 Prof & Associate Prof, Department of Wood Engineering and Technology, Gorgan University of Agricultural Sciences and Natural Resources. Gorgan, Iran

4 Associate Prof, Department of Wood Engineering and Technology, Gorgan University of Agricultural Sciences and Natural Resources. Gorgan, Iran

Abstract

Background and Objectives: Wood, as an organic material, is susceptible to deterioration by destructive factors such as fungi and insects. One approach to protect against these factors is the treatment of wood with preservatives. The use of waterborne preservatives is common due to the numerous advantages. However, when preservative-treated wood is exposed to outdoor environments, it becomes susceptible to weathering and leaching. The use of coatings can be an effective method in this regard. This research investigates the effectiveness of two transparent coatings, acrylic and alkyd, in enhancing the weathering resistance of wood specimens treated with waterborne preservatives. .
Methodology: defect-free poplar wood specimens with dimensions of 12×10×2 cm3 (L, T, R) were prepared and then they were treated with preservatives ACC, CCB, and ACQ-C using the full-cell/pressure impregnation method. Subsequently, acrylic and alkyd transparent coatings were applied to the surface of the specimens. After applying the coatings, the specimens were exposed to natural weathering for one year.
Results: The results indicated that the type of coating significantly influenced the color and adhesion resistance of specimens. Furthermore, the research findings demonstrated that all specimens experienced color changes and a decrease in coating adhesion resistance due to weathering. Among the coatings, the intensity of color changes and deterioration in specimens with acrylic coatings was higher compared to those with alkyd coatings.
Conclusion: In general, it can be concluded that alkyd coatings exhibited better preservative performance against weathering for preservative-treated wood.
Background and Objectives: Wood, as an organic material, is susceptible to deterioration by destructive factors such as fungi and insects. One approach to protect against these factors is the treatment of wood with preservatives. The use of waterborne preservatives is common due to the numerous advantages. However, when preservative-treated wood is exposed to outdoor environments, it becomes susceptible to weathering and leaching. The use of coatings can be an effective method in this regard. This research investigates the effectiveness of two transparent coatings, acrylic and alkyd, in enhancing the weathering resistance of wood specimens treated with waterborne preservatives. .
Methodology: defect-free poplar wood specimens with dimensions of 12×10×2 cm3 (L, T, R) were prepared and then they were treated with preservatives ACC, CCB, and ACQ-C using the full-cell/pressure impregnation method. Subsequently, acrylic and alkyd transparent coatings were applied to the surface of the specimens. After applying the coatings, the specimens were exposed to natural weathering for one year. .
Results: The results indicated that the type of coating significantly influenced the color and adhesion resistance of specimens. Furthermore, the research findings demonstrated that all specimens experienced color changes and a decrease in coating adhesion resistance due to weathering. Among the coatings, the intensity of color changes and deterioration in specimens with acrylic coatings was higher compared to those with alkyd coatings.
Conclusion: In general, it can be concluded that alkyd coatings exhibited better preservative performance against weathering for preservative-treated wood. .

Conclusion: In general, it can be concluded that alkyd coatings exhibited better preservative performance against weathering for preservative-treated wood. .

Keywords

Main Subjects

-Akbarnezhad, M., Rasouli, D., Yousefi, H. and Mashkour, M., 2020. Weath Ering Performance of Beech Wood Coated with Acrylic Paint Containing UV Stabilizers of Dihydroxy Benzophenone and Nano Zinc Oxide. Drvna industrija, 71(4): 403-409.
-Allen, N., Regan, C., McIntyre, R., Johnson, B. and Dunk, W., 1997. The photooxidation and stabilisation of water-borne acrylic emulsions. Progress in Organic Coatings, 32(1-4): 9-16.
-Asadian, M., Rafighi, A. and Khazaian, A., 2021. Study on physical properties and weathering resistance of wood modified by formaldehyde-based resins containing nano zinc oxide. Iranian journal of Wood and Paper industries, 11(4): 599-610.
-ASTM, A., 2010. D4541-09e1, standard test method for pull-off strength of coatings using portable adhesion testers. Adhesives, American Society for Testing and Materials.
-ASTM, H., D2244–Standard Test Method for Calculation of Color Differences from Instrumentally Measured Color Coordinates. Aluminum Sun Shade, 10(70): 13-13.
-Bulian, F., Collavini, F. and Matellon, A., 2017. Investigating the effects of weathering on wood coatings. FME Transactions, 45(3): 405-411.
-Chang, S.T. and Chou, P.L., 2000. Photodiscoloration inhibition of wood coated with UV-curable acrylic clear coatings and its elucidation. Polymer Degradation and Stability, 69(3): 355-360.
-Dawson, B.S., Singh, A.P., Kroese, H.W., Schwitzer, M. A., Gallagher, S., Riddiough, S.J. and Wu, S., 2008. Enhancing exterior performance of clear coatings through photostabilization of wood. Part 2: coating and weathering performance. Journal of Coatings Technology and Research, 5(2): 207.
-Guo, A., Cooper, P.A. and Ung, T., 2005. Fixation and leaching characteristics of acid copper chromate (ACC) compared to other chromium-based wood preservatives. Forest products journal, 55(7/8): 72.
-Humar, M., Pavlič, M., Žlindra, D., Tomažič, M. and Petrič, M., 2011. Performance of waterborne acrylic surface coatings on wood impregnated with Cu-ethanolamine preservatives. Bulletin of Materials Science, 34: 113-119.
-Karbalaei, H., Tarmian, A., Rasouli, D. and Pourmahdian, S., 2022. Effects of UV-curing epoxy acrylate and urethane acrylate coatings incorporated with ZnO nanoparticles on weathering resistance of thermally modified timber. Wood Material Science & Engineering, 17(6): 868-877.
-Nejad, M. and Cooper, P., 2011. Exterior wood coatings. Part-1: Performance of semitransparent stains on preservative-treated wood. Journal of Coatings Technology and Research, 8: 449-458.
-Perrin, F.-X., Merlatti, C., Aragon, E. and Margaillan, A., 2009. Degradation study of polymer coating: improvement in coating weatherability testing and coating failure prediction. Progress in Organic Coatings, 64(4): 466-473.
-Perrin, F.X., Irigoyen, M., Aragon, E. and Vernet, J.,2000. Artificial aging of acrylurethane and alkyd
paints: a micro-ATR spectroscopic study. Polymer degradation and stability, 70(3): 469-475.
-Pintus, V., Wei, S. and Schreiner, M., 2016. Accelerated UV ageing studies of acrylic, alkyd, and polyvinyl acetate paints: Influence of inorganic pigments. Microchemical Journal, 124: 949-961.
-Zhang, J., Kamdem, D. P. and Temiz, A., 2009. Weathering of copper–amine treated wood. Applied Surface Science, 256(3): 842-846.