Your search resulted in 198 documents. Displaying 25 entries per page.
Effects of new fixative additives on leachability of boron wood preservatives
2009 - IRG/WP 09-30507
Borates are well known with their protective capacity against both fungi and insects with low mammalian toxicity and environmental acceptable. However, boron itself does not ensure the appropriate protection for wood in the exterior applications because of their easily depletion from the treated wood under wet conditions. In this study, the potential use of monoglyceride and polyvinyl alcohol prod...
A Mohareb, J Henry, E Wozniak, P Gérardin
Protection mechanisms of modified wood against decay by white and brown rot fungi
2010 - IRG/WP 10-10713
The resistance of beech and pine wood blocks treated with 1,3-dimethylol-4,5-dihydroxyethylene urea (DMDHEU) against T. versicolor and C. puteana increased with increasing WPG. Full protection (mass loss below 3%) was reached at WPGs of approximately 15% (beech) and 10% (pine). Metabolic activity of the fungi in the wood blocks was assessed as heat or energy production determined by isothermal mic...
C Mai, P Verma, Yanjun Xie, J Dyckmans, H Militz
Fungal Attack on Lignin and Cellulose: Elucidation of Brown- and White-Rot Mechanisms Comparing Biomimetic and In-Vivo Degradation Patterns
2010 - IRG/WP 10-10714
This paper examines research and hypotheses that have been developed over several years on wood degradation mechanisms. This information is combined with new data and analyses to explain why wood decay patterns caused by brown-rot fungi and specific types of white-rot fungi are different. New data, including work with both biomimetic studies on low molecular weight compounds, degradative enzymes, ...
V Arantes, B Goodell, A M F Milagres, Yuhui Qian, T Filley, J Jellison, S Kelley
Determination of a fixation time of wood preservatives: A discussion paper
2010 - IRG/WP 10-20436
The intention of that paper is to initiate a discussion on the basis of a French method in combination with a German approach regarding the need of a method for the determination of a fixation time and especially to obtain input as well as ideas concerning a possible test design. Since no harmonised European approach exists up to now concerning the determination of a fixation time, CEN TC 38 (2009...
E Raphalen, E Melcher
Effects of polyvinyl alcohol on leachability and efficacy of boron wood preservatives against fungal decay and termites attack
2010 - IRG/WP 10-30526
In this study, the use of polyvinyl alcohol (PVA) as boron fixative agent was investigated. Two levels of PVA (2.5 and 4%) were evaluated with disodium octaborate tetrahydrate (DOT) at three concentrations (1, 2 and 4% boric acid equivalent (BAE) using a double vacuum impregnation processes on Scots pine sapwood specimens. Leaching was performed according to a laboratory leaching procedure. Boron ...
A Mohareb, M F Thévenon, E Wozniak, P Gérardin
Laboratory evaluation of borate amine: Copper derivatives in wood for fungal decay
2010 - IRG/WP 10-30543
The aims of this study were to evaluate borate: amine: copper derivatives in wood for fungal decay protection as well as the permanence of copper and boron in wood. Wood treated with each of four derivatives of borate:amine:copper prevented fungal decay. Disodium tetraborate ecahydrate (Borax):amine:copper derivatives with retentions of 0.61 to 0.63% after water leaching prevented decay by Gloeo...
G Chen
Chapter 13 - Slow fixation of CCA-treated bamboo
2007 - IRG/WP 07-10635-13
Chromated copper arsenate (CCA) leachability tests on full-cell
pressure impregnated (with 2-3% CCA solution) and slow dried (six
months air-drying under cover) bamboo block of three major
bamboo species of Bangladesh revealed initial insignificant leaching
of CCA within first week and no leaching in next week. Use of low
concentration of CCA, release of particle form of CCA due to
exposure ...
A K Lahiry
Chapter 14 - Accelerated fixation of CCA-treated bamboo
2007 - IRG/WP 07-10635-14
Chromated copper arsenate type C (CCA-C) fixation study on
impregnated (with adequate w/v 6% CCA solution) then boiled,
oven-dried, normal, air-dried and steamed bamboo slices of airdried
borakbamboo (Bambusa balcooa Roxb.) of Bangladesh,
revealed almost complete fixation in steamed (accelerated fixation)
and air-dried (3 weeks, slow fixation) bamboo slices compared to
moderate to low fixati...
A K Lahiry
Fixed Borates Anyone?
2011 - IRG/WP 11-30563
The quest for a borate based preservative system that resists leaching or is “fixed” has long been a research goal. Boron fixation has been attempted with numerous strategies but there have been problems associated with past methods. This paper discusses new fixation systems based on bio-materials and presents up to five year outdoor exposure testing on full-size decks. Generally, the new f...
C R McIntyre, M A Lake
Tannin resin-boron associations: Leaching and biological resistance
2012 - IRG/WP 12-30587
The easy leaching of boron in wood preservation formulations has allowed to use this fungicide only for short term applications. The recently discovered adduct with flavonoids allows boron to resist longer periods of time within wood and consequently extend its life. Two different leaching treatments were compared and the fungal and termite decay was examined. The biological tests have shown extre...
G Tondi, S Wieland, N Lemenager, A Petutschnigg, A Pizzi, M-F Thevenon
A survey of factors affecting decay resistance of wood modified with acetic anhydride
2012 - IRG/WP 12-40594
From the range of information published, acetylation appears well suited to provide adequate protection against biological attack for materials derived from typically non-durable wood species. Acetylated wood is now commercially available both in Europe and in the USA. But still there are a lot of unanswered questions related to fungal decay mechanisms in acetylated wood. The paper summarize exist...
G Alfredsen, P O Flæte, H Militz
Fixation and leaching characteristics of Malaysian tropical hardwoods treated with CCA-C
2012 - IRG/WP 12-50289
The fixation and leaching characteristics of 8 Malaysian tropical hardwood (MTH) species treated with chromated copper arsenate (CCA-C) wood preservative were examined. The species evaluated were Acacia (Acacia mangium), Bintangor (Calophyllum sp.), Geronggang (Cratoxylon arborescens), Medang (Litsea sp.), Meranti rambai daun (Shorea acuminata), Putat (Planchonia sp.), Ramin (Gonystylus sp.) and S...
S Salim, S Shahomlail, Z Ashaari, Yong-Seok Choi, Gyu-Hyeok Kim
Preliminary testing of spiroborate esters as wood preservatives
2013 - IRG/WP 13-30614
Fungicide and insecticide properties of boric acid are known since 30’s of the last century, but high solubility and leachability of inorganic borates limit their use for only applications not directly exposed to liquid water. A number of attempts were made to fixate borate salts into the wood structure but this research topic is still up to date and undiscovered. Water insoluble organoboron est...
D Panov, N Terziev
The Chelator Mediated Fenton System in the Brown Rot Fungi: Details of the Mechanism, and Reasons Why it has Been Ineffective as a Biomimetic Treatment in some Biomass Applications – a Review
2014 - IRG/WP 14-10828
The chelator-mediated Fenton (CMF) reaction requires the action of two types of chelating compounds. The first chelator, oxalate, solubilizes and then sequesters iron, and the second chelator reduces iron. Iron reduction must be controlled near the fungal hyphae to prevent damaging Fenton chemistry from occurring in that location. Similarly, iron reduction must be promoted within the wood/plant ce...
B S Goodell, M Nakamura, J Jellison
Chemistry of copper preservative treated wood
2014 - IRG/WP 14-30651
The reaction chemistry of micronized copper wood preservatives is fundamentally different from any previous inorganic preservative system. In order to study the chemistry, analytical procedures had to be developed which allowed the determination of the total copper as well as the copper which reacted with the wood forming copper-wood complexes. With the success of this approach it also became poss...
Wei Xue, P Kennepohl, J N R Ruddick
State of Nanocopper Fixation by Steam-Densification
2016 - IRG/WP 16-40723
This study was aimed to investigate the effect of steam treatment before densification on leachability and dimensional stability of nanocopper impregnated poplar (Popolus alba). Wood samples were impregnated with nanocopper suspension (200 and 400 ppm) for 20 minutes under 4 bar pressure. Steaming process was done before densification at 150°C for 2 hour. Radial densification (33%) was done conse...
G Rassam, A Talaei, A Ahmadi
Enhancing Our Understanding of Brown Rot Mechanisms through Catalytic Pretreatment and Cellulase Cocktail
2018 - IRG/WP 18-10909
A catalytic mechanism, described as the “chelator-mediated Fenton” (CMF) mechanism, is proposed to mimic the non-enzymatic action of brown rot fungi. A CMF treatment was used together with an enzymatic cocktail to study how wood was deconstructed and solubilized. This was done in-part to determine if the treatment mimicked the action of brown rot fungi, but also to explore improved treatment p...
S Tabor, L Orjuela, D Contreras, G Alfredsen, J Jellison, S Renneckar, B Goodell
Development of a new method for wood hydrophobizing and fixation of copper compounds by chemical hardening of vegetable based modified oils
2016 - IRG/WP 16-40754
Wood products with ground and direct water contact, but without sufficient biological durability, have to be protected against biological degradation by fungi and other microorganisms. Due to European legislation (Biocidal Products Regulation 528/2012), the selection of possible chemical agents, which are still allowed to be used, is diminishing rapidly. The use of previously widely applied, very ...
C Swaboda, M Fischer, K Jacobs
Non-stochiometric oxidation and ROS generation promoted by guaiacol lignin structures and lignocelluose surfaces may be a component of brown rot fungal degradation mechanisms
2019 - IRG/WP 19-10937
Model guaiacol compounds representing lignin monomers, as well as DHP-lignin and wood flour of controlled particle size were used to assess iron reduction at the pH of the natural wood cell wall. All compounds functioned as electron donors for ferric iron, with the lignin monomers demonstrating capacity for non-stochiometric reduction of iron with multiple moles of ferric ion reduced per mole of l...
Y Tamarua, M Yoshidaa, L D Eltisb, B Goodell
Using X-ray scattering to elucidate the mechanisms behind the moisture and fungal decay resistance of epoxybutene modified wood
2019 - IRG/WP 19-40854
Chemical modification of the hydroxyl groups of wood can improve the properties of wood by providing moisture and biological resistance, as well as dimensional stability. Southern pine solid wood was chemically modified to various weight percentage gains (WPG) with epoxybutene (EpB, 8%-38% WPG). After modification, specimens were extracted with a toluene: ethanol (2:1) solution for 2 hours or wate...
R E Ibach, N Plaza
Geopolymer as a fixation method for tannin-based wood preservatives
2023 - IRG/WP 23-30774
This study aims to test if a second step impregnation with a geopolymer solution can fix Colatan GT10, a commercial extract rich in tannins, to wood, reducing their leaching and improving their performance as wood preservatives. Scots pine sapwood specimens of 40×10×5 mm3 were impregnated with Colatan GT10 tannin mix, geopolymer, and as combined treatment Colatan GT10 with subsequent geopolymer ...
Y M López-Gómez, A Barbero-López, A Haapala
How the biochemical activities of polyphenols may be effective for the protection of wood deterioration by termites?
2023 - IRG/WP 23-30789
In spite of the remarkable mechanical characteristics of wood for building construction and furniture industry, this material is prone to biodeterioration by xylophagous organisms. This compromises its durability and performances during storage and services, and results in considerable economical losses estimated by the billions. Protection against fungi, termites and other wood biodegrading organ...
J-P Joseleau, D Messaoudi, K Ruel
Leaching and chemical redistribution of CCA components in refractory heartwood of E. nitens
2024 - IRG/WP 24-41011
Chromated Copper Arsenate (CCA) is a wood preservative widely used to protect against fungal and insect attack. The fixation mechanism of CCA involves complex chemical reactions, including the reduction of chromium (VI) to chromium (III) and the formation of insoluble complexes. Despite fixation efforts, a portion of CCA components tends to leach from treated wood, influenced by factors like wood ...
J R Vargas, L Yermán, K C Wood, T Singh