Amongst polyphenols, tannins belong to the most effective chemical protection systems against biological attack on trees. Tannins are water-soluble and are thus leached out easily when used for wood protection. In situ polymerized tannin-hexamine wood preservatives have better leaching resistance (LR), but they do not resist weathering. In this study, tannin copolymer formulations were prepared with hexamine, formaldehyde, furfural, glyoxal, furfuryl alcohol and maleic anhydride, impregnated in wood, and cured at higher temperatures. The wood samples treated with these formulations were tested for their anti-swelling efficiency (ASE), leaching behavior, mechanical properties, and their resistance against fire, weathering and biological attack. Several tannin-treated specimens showed improved hardness and enhanced leaching and fire resistance. Some formulations also responded well to artificial weathering cycles, but natural weathering cycles deteriorated their performance. Samples treated with maleic anhydride showed improved leachability and high biological resistances, even without the addition of inorganic biocides. These organic and bio-friendly products can be considered as promising alternatives to heavy metal-based wood preservatives.
Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: The study was financed for one part by the European Union with the ERA-Net Wood Wisdom program and namely to the project “BIOCOPOL – Enhancing wood durability and physical properties through innovative bio-based sustainable treatments”.
Employment or leadership: None declared.
Honorarium: None declared.
Arbenz, A., Avérous, L. (2015) Chemical modification of tannins to elaborate aromatic biobased macromolecular architectures. Green Chem. 17:2626–2646. Search in Google Scholar
Ballerini, A., Despres, A., Pizzi, A. (2005) Non-toxic, zero emission tannin-glyoxal adhesives for wood panels. Holz Roh. Werkst. 63:477–478. Search in Google Scholar
Cogulet, A., Blanchet, P., Landry, V. (2016) Wood degradation under UV irradiation: a lignin characterization. J. Photochem. Photobiol. 158:184–191. Search in Google Scholar
DIN 52185 (1976) Testing of wood; compression test parallel to grain. Search in Google Scholar
EN 84 (1997) Wood Preservatives – Accelerated Ageing of Treated Wood Prior to Biological Testing – Leaching Procedure. Search in Google Scholar
EN 113 (1996) Wood Preservatives – Test Method for Determining the Protective Effectiveness against Wood Destroying Basidiomycetes – Determination of the Toxic Values. Search in Google Scholar
EN 350 (2016) Durability of Wood and Wood-based Products – Testing and Classification of the Durability to Biological Agents of Wood and Wood-based Materials. Search in Google Scholar
EN 927-6 (2006) Paints and Varnishes – Coating Materials and Coating Systems for Exterior Wood – Part 6: Exposure of Wood Coatings to Artificial Weathering using Fluorescent UV Lamps and Water. Search in Google Scholar
EN 1534 (2000) Wood Flooring – Determination of Resistance to Indentation – Test Method. Search in Google Scholar
Faix, O., Németh, K. (1988) Monitoring of wood photodegradation by DRIFT-spectroscopy (Short Note). Holz Roh-Werkst. 46:112. Search in Google Scholar
Hagerman, A.E., Riedl, K.M., Jones, G.A., Sovik, K.N., Ritchard, N.T., Hartzfeld, P.W., Riechel, T.L. (1998) High molecular weight plant polyphenolics (tannins) as biological antioxidants. J. Agr. Food Chem. 46:1887–1892. Search in Google Scholar
Hawthorne, D.G., Solomon, D.H. (1976) Kinetic and thermodynamic factors in polymer chemistry. J. Polym. Sci. 55:211–217. Search in Google Scholar
Hill, C.A. Wood Modification: Chemical, Thermal and other Processes (Vol. 5). John Wiley and Sons, Hoboken, NJ, USA, 2007. Search in Google Scholar
Kain, G., Güttler, V., Barbu, M.C., Petutschnigg, A., Richter, K., Tondi, G. (2014) Density related properties of bark insulation boards bonded with tannin hexamine resin. Eur. J. Wood Wood Prod. 72:417–424. Search in Google Scholar
Kirker, G.T., Blodgett, A.B., Arango, R.A., Lebow, P.K., Clausen, C.A. (2013) The role of extractives in naturally durable wood species. Int. Biodeter. Biodegr. 82:53–58. Search in Google Scholar
Kryn, J.N. (1954) Information leaflet foreign woods-Quebracho. U.S. Forest product Lab. Rep. 1969:1–10. Search in Google Scholar
Laks, P.E., McKaig, P.A., Hemingway, R.W. (1988) Flavonoid biocides: wood preservatives based on condensed tannins. Holzforschung 42:299–306. Search in Google Scholar
Lotz, W.R., Hollaway, D.F. (1988) Weatherproofing Decay Resistance, Tannin Impregnation. US Patent 4,732,817. Search in Google Scholar
Missio, A.L., Tischer, B., dos Santos, P.S., Codevilla, C., de Menezes, C.R., Barin, J.S., Haselein, C.R., Labidi, J., Gatto, D.A., Petutschnigg, A., Tondi, G. (2017) Analytical characterization of purified mimosa (Acacia mearnsii) industrial tannin extract: single and sequential fractionation. Sep. Purif. Technol. 186:218–225. Search in Google Scholar
Németh, K., Faix, O. (1991) Application of the spectrometric properties of lignin for tracing photodegradation of wood. In: Proceedings of the “1st European Workshop on Lignocellulosics and Pulp (EWLP ’90)”, Utilization and Analysis of Lignins, September 18–20, 1990, Hamburg-Bergedorf. Mitteilungen der BFH, Nr. 168, Buchhandlung Max Wiedebusch, Dammtorstr. 20, Hamburg 36, FRG. pp. 348–357. Search in Google Scholar
Pizzi, A. Advanced Wood Adhesives Technology. CRC Press, Dekker, New York, 1994. Search in Google Scholar
Pizzi, A. (2008) Tannins: Major Sources, Properties and Applications. Monomers, Polymers and Composites from Renewable Resources, pp. 179–199. Elsevier, New York. ISBN: 978-0-08-045316–3. Search in Google Scholar
Pizzi, A., Scharfetter, H.O. (1978) The chemistry and development of tannin-based adhesives for exterior plywood. J. Appl. Polym. Sci. 22:1745–1761. Search in Google Scholar
Reyer, A., Tondi, G., Berger, R.J.F., Petutschnigg, A., Musso, M. (2016) Raman spectroscopic investigation of tannin-furanic rigid foams. Vibr Spectrosc. 84:58–66. Search in Google Scholar
Scalbert, A. (1992) Tannins in woods and their contribution to microbial decay prevention. In: Plant Polyphenols. Springer, US. pp. 935–952. Search in Google Scholar
Scalbert, A., Cahill, D., Dirol, D., Navarrete, M.A., De Troya, M.T., Van Leemput, M. (1998) A tannin/copper preservation treatment for wood. Holzforschung 52:33–138. Search in Google Scholar
Schwanninger, M., Rodrigues, J.C., Pereira, H., Hinterstoisser, B. (2004) Effects of short-time vibratory ball milling on the shape of FT-IR spectra of wood and cellulose. Vibr. Spectrosc. 36:23–40. Search in Google Scholar
Sen, S., Tascioglu, C., Tırak, K. (2009) Fixation, leachability, and decay resistance of wood treated with some commercial extracts and wood preservative salts. Int. Biodeter. Biodegr. 63:135–141. Search in Google Scholar
Tascioglu, C., Yalcin, M., de Troya, T., Sivrikaya, H. (2012) Termiticidal properties of some wood and bark extracts used as wood preservatives. Bioresources 7:2960–2969. Search in Google Scholar
Tascioglu, C., Yalcin, M., Sen, S., Akcay, C. (2013) Antifungal properties of some plant extracts used as wood preservatives. Int. Biodeter. Biodegr. 85:23–28. Search in Google Scholar
Taylor, A.M., Gartner, B.L., Morrell, J.J. (2002) Heartwood formation and natural durability-a review. Wood Fiber Sci. 34:587–611. Search in Google Scholar
Thevenon, M.F., Tondi, G., Pizzi, A. (2009) High performance tannin resin-boron wood preservatives for outdoor end-uses. Eur. J. Wood Wood Prod. 67:89–93. Search in Google Scholar
Tondi, G. (2017) Tannin-based copolymer resins: synthesis and characterization by solid state 13C NMR and FT-IR spectroscopy. Polymers 9:23. Search in Google Scholar
Tondi, G., Petutschnigg, A. (2015) Middle infrared (ATR FT-MIR) characterization of industrial tannin extracts. Ind. Crops Prod. 65:22–428. Search in Google Scholar
Tondi, G., Wieland, S., Lemenager, N., Petutschnigg, A., Pizzi, A., Thevenon, M.F. (2012a) Efficacy of tannin in fixing boron in wood. BioResources. 7:1238–1252. Search in Google Scholar
Tondi, G., Palanti, S., Wieland, S., Thevenon, M.F., Petutschnigg, A., Schnabel, T. (2012b) Durability of tannin-boron-treated timber. Bioresources 7:5138–5151. Search in Google Scholar
Tondi, G., Wieland, S., Wimmer, T., Thevenon, M.F., Pizzi, A., Petutschnigg, A. (2012c) Tannin-boron preservatives for wood buildings: mechanical and fire properties. Eur. J Wood Wood Prod. 70:689–696. Search in Google Scholar
Tondi, G., Schnabel, T., Wieland, S., Petutschnigg, A. (2013a) Surface properties of tannin treated wood during natural and artificial weathering. Int. Wood Prod. J. 4:150–157. Search in Google Scholar
Tondi, G., Thevenon, M.F., Pizzi, A., Mies, B., Standfest, G., Petutschnigg, A., Wieland, S. (2013b) Impregnation of Scots pine and beech with tannin solutions: effect of viscosity and wood anatomy in wood infiltration. Wood Sci. Techn. 47:615–626. Search in Google Scholar
Tondi, G., Haurie, L., Wieland, S., Petutschnigg, A., Lacasta, A., Monton, J. (2014) Comparison of disodium octaborate tetrahydrate (DOT) and tannin-boron based formulations as fire retardant for wood structures. Fire Mat. 38:381–390. Search in Google Scholar
Tondi, G., Hu, J., Rizzo, F., Buh, J., Medved, S., Petutschnigg, A., Thevenon, M.F. (2017) Tannin-caprolactam and tannin-PEG formulations as outdoor wood preservatives: weathering properties. Ann. For. Sci. 74:19. Search in Google Scholar
Yamaguchi, H., Okuda, K.I. (1998) Chemically modified tannin and tannin-copper complexes as wood preservatives. Holzforschung 52:596–602. Search in Google Scholar
The online version of this article offers supplementary material (https://doi.org/10.1515/hf-2018-0130).
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