Efficacy of Tannin in Fixing Boron in Wood: Fungal and Termite Resistance
نویسندگان
چکیده
The easy leaching of boron from wood preservation formulations has limited the use of this highly active fungicide. The recently discovered adduct with flavonoids allows boron to be retained for longer periods of time within wood and consequently to extend its life. Two different leaching treatments were compared, and the fungal and termite decay were examined. The biological tests showed extremely high resistance of the leached samples against both fungus (Coriolus Versicolor and Coniophora Puteana) and termites (Reticulitermes Santonensis). The retention of 2.5 kg/m3 was determined as the threshold of efficacy of boron in flavonoid-based wood preservative. Furthermore, solid state C-NMR analysis of the tannin resin indicated that boron can be covalently fixed to the tannin-hexamine network.
منابع مشابه
Environmentally Friendly Wood Preservative System Based on Polymerized Tannin Resin-boric Acid for Outdoor Applications♣
Boron compounds are used as wood preservatives as they are both fungicide and insecticide, relatively inexpensive and environmentally acceptable. Nevertheless, in the field of wood protection, borates are only used for indoor non-exposed applications or in association with other biocides, due to their main disadvantage of being readily leachable from treated wood. To overcome this problem, bori...
متن کاملImprovement of the Durability of Heat-treated Wood against Termites
Thermal modification is an attractive alternative to improve the decay durability and dimensional stability of wood. However, thermally modified wood is generally not resistant to termite attacks, limiting the field of application of such materials. One way to overcome this drawback is to combine thermal modification treatment with an additional treatment. One such treatment is the impregnation...
متن کاملContribution of Extractives to Fungal and Termite Resistance of Brazilian Wood Bagassa guianensis AUBL
The heartwood of Bagassa guianensis AUBL., which grows widely in South America, is empirically known to be durable against fungal and insects decay. In this study, we evaluated the fungal and termite resistance of B. guianensis wood, and conducted the separation of substances having the antifungal and antitermite properties. As the results, B. guianensis wood has excellent durability against bo...
متن کاملTermite Resistance of MDF Panels Treated with Various Boron Compounds
In this study, the effects of various boron compounds on the termite resistance of MDF panels were evaluated. Either borax (BX), boric acid (BA), zinc borate (ZB), or sodium perborate tetrahydrate (SPT) were added to urea-formaldehyde (UF) resin at target contents of 1%, 1.5%, 2% and 2.5% based on dry fiber weight. The panels were then manufactured using 12% urea-formaldehyde resin and 1% NH(4)...
متن کاملEffects of Rosin Sizing Agent on the Fixation of Boron in Styrax
The aim of this study was to evaluate the effect of rosin upon fixing boron in Styrax tonkinensis (Piere) wood treated with mixtures of 3% boric acid and 1% rosin sizing agent. After treatment, wood samples were also analyzed by scanning electron microscope observation and energy-dispersive X-ray spectroscopy (SEM-EDX). The results showed that all boron-rosin formulations impregnated Styrax ton...
متن کامل