Comparison of Some Physical and Mechanical Properties of Waterborne Acrylic Coating Systems Containing Commercial UV Absorbers and Tree Bark Extracts
Öz
Aim of study: The aim of this study was to compare solid content, dry film thickness, and adhesion strength of different tree bark extract based and a commercial UV absorber.
Materials and methods: Waterborne acrylic-based coating systems containing 5 different tree bark extracts (maritime pine, Calabrian pine, black pine, alder, fir) and a commercial UV absorber (Tinuvin 400 DW) were applied to 2 different wood species; Scots pine (Pinus sylvestris L.) and beech (Fagus orientalis L.). The dry-film thicknesses of the coatings were measured with light microscopy. The adhesion strength of the coatings was determined to investigate the bonding ability of the coatings with wood surfaces. The solid contents of the coatings were also determined.
Main results: Permeability is an important parameter for dry-film thickness and adhesion strength. Wood species also influenced the dry-film thickness as well as adhesion strength. The dry-film thicknesses of the coatings containing bark extracts were higher than those with commercial UV absorbers. Similarly, the solid content of the coating containing maritime pine bark extract was found to be the highest.
Highlights: The dry-film thickness and adhesion strength of waterborne acrylic coatings on wood substrate seem to be affected by addition of tree bark extracts.
Anahtar Kelimeler
Acrylic Coating,Adhesion Strength,Dry Film Thickness,Tree Bark Extract,Pull-Off Test
Kaynakça
- ASTM, D. (2002). 4541, Standard Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers. Annual Book of ASTM Standards, 1-13.
- Bardage, S.L. & Bjurman, J. (1998). Adhesion of waterborne paints to wood. Journal of Coatings Technology, 70(78), 39-47.
- Bulian, F. & Graystone, J.A. (2009). Wood coatings: Theory and Practice. Oxford: Elsevier.
- Decker, C., Masson, F. & Schwalm, R. (2004). Weathering Resistance of Water-Based UV-Cured Polyurethane-Acrylate Coatings. Polymer Degradation and Stability, 83, 309-320.
- EN ISO 2808 (2007) Paints and varnishes—determination of film thickness.
- Evans, P.D.&Chowdhury M.J. (2010). Photostabilization of wood with higher molecular weight UV absorbers. In 41st Annual Meeting Of The International Research Group On Wood Protection, Biarritz, France.
- Feist W.C. & Hon D.N.-S. (1984). In: Rowell R. M., Ed. “The Chemistry of solid wood”, Chapter 11: Chemistry of weathering and protection. advances in chemistry series 207, Washington, Dc: American Chemical- Society.
- Feist, W.C. (1990). Weathering performance of painting wood pretreated with water-repellent preservatives. Forest Products Journal, 40(7/8), 21-26.
- Gindl M., Reiterer A., Sinn G. & Stanzl-Tschegg S.E. (2004). Effects of surface ageing on wettability, surface chemistry, and adhesion of wood, Holz als Roh- und Werkstoff, 62 (4), 273-280.
- Grüll, G., Tscherne, F., Spitaler, I. & Forsthuber, B. (2014). Comparison of wood coating durability in natural weathering and artificial weathering using fluorescent UV-lamps and water. European Journal of Wood and Wood Products, 72(3), 367-376.