Your search resulted in 198 documents. Displaying 25 entries per page.
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
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
Characterization of wood modification prepared by in situ polymerization with pre-polymer and the mechanism of modification
2013 - IRG/WP 13-40633
Chemical modification of wood is a potential way to obtain high quality wood. In this study, the fast-growing poplar was impregnated with modifier using a pulse-dipping machine by in situ polymerization. Fungal decay analysis, mechanical properties and dimension stability of the natural and modified woods were investigated. The wood samples were also characterized by X-ray diffraction (XRD) Therma...
Qian Lang, Zeng Bi, Junwen Pu
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
Modern Instrumental Methods to Investigate the Mechanism of Biological Decay in Wood Plastic Composites
2014 - IRG/WP 14-40674
Various instrumental techniques were used to study the fungal decay process in wood plastic composite (WPC) boards. Commercial boards exposed near Hilo, Hawaii (HI) for eight years in both sun and shadow locations were inspected and tested periodically. After eight years of exposure, both boards were evaluated using magnetic resonance imaging (MRI), while a selected area of the board exposed in sh...
G Sun, R Ibach, M Gnatowski, J Glaeser, M Leung, J Haight
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
Modifying wood with paraffin wax emulsion impregnation and thermal modification: hydrophobization effect and mechanism of the combined treatment
2016 - IRG/WP 16-40726
The aim of this study was to enhance the water repellency of wood by a combined treatment of paraffin wax emulsion (PWE) impregnation and thermal modification. Two different treating procedures were used to modify the southern pine (pinus spp.). One is first PWE impregnation and then thermal modification, another is first thermal modification and then PWE impregnation. The treated samples were imm...
Wang Wang, Jinzhen Cao, Cong Chen
Role of cell wall specific moisture content on the brown-rot fungal attack on wood
2016 - IRG/WP 16-40736
Wood is a hydroscopic resource because the cell wall polymers contain hydroxyl and other oxygen-containing groups that attract moisture through hydrogen bonding. Moisture content varies with changing moisture content in its environment. The moisture content in wood is responsible for many of the performance properties we observe. The strength properties of wood are dependent on the moisture con...
R M Rowell
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
Mechanism of nano metal fluorides against fungi
2018 - IRG/WP 18-30730
Metal fluoride nanoparticles are promising because of their low water solubility, which reduces the need for fixatives required in widely used active ingredient in wood preservatives such as copper and boron. Wood specimens treated with fluoride sols of MgF2 and CaF2 have been tested against brown-rot fungi (Coniophora puteana and Rhodonia placenta) in accordance with EN 113 and against termites (...
S M Usmani, K Klutzny, I Stephan, T Hübert, E Kemnitz
Recent findings clarifying the mechanism of brown-rot decay protection in acetylated wood
2018 - IRG/WP 18-40827
This paper summarizes the findings obtained during my PhD research over the past three years. The results provide insights which help to understand the enhanced brown-rot decay resistance of acetylated wood with particular emphasis on the role of water. The protection acetylation provides is derived from moisture exclusion within the acetylated cell wall, but the exact mechanism by which water is ...
G Beck
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
The anti-weathering mechanism of extractives in thermally modified Scots pine
2019 - IRG/WP 19-40880
Results from the electron spin-resonance spectroscopy (ESR) analysis indicated that thermally modification of wood can inhibit the generation of phenoxyl radicals during UV irradiation and consequently lead to the increase of the color stability of wood. In order to clarify the evolution and role of extractives in thermally modified wood during the process of weathering, the compositions of aceton...
H Shen, J Cao
The cellulose binding mechanism of a novel cellulose binding domain from the brown-rot fungus Gloeophyllum trabeum
2023 - IRG/WP 23-11021
In nature, wood decay is caused by various wood-rotting basidiomycetes. Wood-rotting basidiomycete are mainly divided into white-rot fungi and brown-rot fungi. Their main carbon source is cellulose of the wood cell wall during wood decay, and they produce a variety of enzymes to decompose cellulose. The cellulolytic enzymes often possess a cellulose binding domain (CBD) as an additional domain con...
M Aoki, Y Kojima, M Wada, M Yoshida
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
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