Your search resulted in 237 documents. Displaying 25 entries per page.
Effect of the nature of the inert atmosphere used during thermal treatment on chemical composition, decay durability and mechanical properties of wood
2013 - IRG/WP 13-40625
Wood heat treatment is an attractive alternative to improve decay resistance of low natural durability wood species. Nowadays, several types of thermal treatments of wood exist. These treatments differ mainly by the nature of the inert atmosphere used to avoid wood combustion which may correspond to: nitrogen, vacuum, steam or oil. Decay resistances as well as mechanical properties are strongly co...
K Candelier, S Dumarçay, A Pétrissans, M Pétrissans, P Gérardin
Study of UV resistance and natural weathering of coatings on chemically modified wood
2013 - IRG/WP 13-40629
In this study, UV resistance and weathering performance of rubberwood (Hevea brasiliensis) and radiata pine (Pinus radiata) modified with benzoyl chloride and acetic anhydride was studied. Performance of polyurethane based wood coatings on modified wood was also evaluated. Unmodified and chemically modified specimens were exposed to accelerated and natural weathering. Modified and unmodified woo...
K K Pandey, K Srinivas
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
Quantification of copper and chromium in field stakes after different exposure times: Remaining metal content and distribution
2013 - IRG/WP 13-50291
In order to determine the distribution of copper and chromium as well as their remaining concentration EN 252 specimens and thicker pine sapwood stakes (non standard format) were treated with a commercial CC salt in a vacuum pressure process. The stakes were installed in the test field of the Institute of Wood Research, Hamburg, in August 2010. In all cases three stakes were removed after 4, 8, 12...
T Liese, M Bahmani, E Melcher
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
Changes in mechanical and chemical properties of wood exposed outdoors
2014 - IRG/WP 14-20550
The aim of this study was to investigate differences in certain mechanical and chemical properties of three different wood species (common beach (Fagus sylvatica), Norway spruce (Picea abies), and copper-ethanolamine (CuE) impregnated Norway spruce (Picea abies)) that were exposed in use class 3 (CEN, 2006) for periods between 4 and 30 months. The results show, that changes in the investigated me...
N Thaler, C Brischke, D Žlindra, V Vek, M Humar
Scanning Transmission X-ray Microscopy as a tool for examining chemical changes in wood cell walls due to enzymatic activity
2014 - IRG/WP 14-20556
As development of techniques for examining enzymatic activity on solid, complex biological materials, is considered to be an important factor in further development of enzyme applications and for understanding the decay of plant materials, this study explores applicability of Scanning Transmission X-ray Microscope (STXM) for determining chemical changes in enzymatically treated samples at the cell...
D Jeremic, R Goacher, R Yan, C Karunakaran, E R Master
Resistance to Decay Fungi of Scots Pine Impregnated with Natural and Chemical Preservatives
2014 - IRG/WP 14-30650
In this study, heart-wood and sap-wood specimens of the Scots pine which is naturally grown in Turkey were treated with natural (valex) and some chemical preservatives such as CCA - C (Copper / Chrome / Arsenic), CBA - A (Copper / Boron / Azole). The wood protective efficacies of these preservatives were investigated by means of fungi decay test (EN 113).
As a result of the study it was found t...
S Yildiz, U B Şimşek
VOC-free remedial treatment agent on organic solvent basis with surface cleaning by photocatalysis using titanium dioxide
2014 - IRG/WP 14-40651
Due to the EU Regulations according to the harmonisation of the European market of biocidal products and the EU Regulations regarding emissions of volatile organic compounds in residential properties a new VOC free yet organic solvent based remedial treatment agent is introduced including a potential method to clean up the wooden surface of remaining biocides after a remedial treatment using photo...
H Ahl, J Fromm, P Jüngel, E Melcher, M Pallaske
Chemical composition of extractives of different wood compartments of Pinus merkusii and their potential implication in wood durability
2015 - IRG/WP 15-10841
Amounts and nature of extractives differ strongly according to the compartment of wood and to the nature of the wood species. Previous studies reported that knotwood of several European Pinus sp. contains extractives contents much higher than stemwood consisting mainly of lignans which may find valuable applications in cosmetic, nutraceutic or pharmaceutic sectors. Different explanations have been...
A Wijayanto, S Dumarçay, R Kartika Sari, W Syafii, P Gérardin, C Gérardin-Charbonnier
Durability of Fence Posts of Four Wood Species After 20 Years in Field Test
2015 - IRG/WP 15-30670
In the past years, wood consumption from native forests has drastically reduced the availability of wood. Fast-growing species such as Pinus and Eucalyptus suitably impregnated with chemicals may show a service life equal or higher than hardwood with high natural durability. The field tests have been an alternative widely used to evaluate the durability of wood and the efficiency of preservatives....
A Florian da Costa, A C Salgado de Freitas, E Meneses Oliveira
How intraspecific radial variability of the European Oak’s may influence mild pyrolysis process and durability of the material
2016 - IRG/WP 16-40725
Last decades wood is promoted as building material. Unprotected wood exposed to outdoor conditions undergoes a variety of degradation induced essentially by fungi attacks. Heat treatment of wood by mild pyrolysis (180°C T 240°C under inert atmosphere) is a preservation process with a weak environmental impact, and therefore, is viewed as an interesting alternative to the chemical impregnation me...
J Hamada, A Pétrissans, F Mothe, M Pétrissans, P Gérardin
Optimising wood chemical modification with lactic acid oligomers by screening of processing conditions and chemical additives
2016 - IRG/WP 16-40741
Oligomer systems based on lactic acid (OLA), were impregnated in wood and polymerised in-situ by heat treatment to improve the properties of the treated wood especially regarding anti-swelling efficiency (ASE), hygroscopicity, water leaching resistance and durability. This article relates the optimisation of the heat treatment conditions and the consideration of selected chemicals for improvement ...
C Grosse, M-F Thévenon, M Noël, P Gérardin
Exterior birch plywood: potentiality of the thermo-hydro treatment
2016 - IRG/WP 16-40743
It has been found in the present study that, in laboratory fungi tests after leaching with water (EN 84), exterior birch (Betula spp.) plywood, as birch solid wood, is subjected to degradation by rot fungi. This limits the use of such plywood outdoors or in building structures in high humidity conditions. The possibility to improve the birch plywood fungal resistance was investigated in two ways: ...
B Andersons, I Andersone, A Meija-Feldmane, I Irbe, A Janberga, J Grinins
Chemical, physical-mechanical characterization and durability of thermally modified beech and ash wood by thermo-vacuum process (Termovuoto)
2016 - IRG/WP 16-40758
The paper illustrates part of the results from the CIP Eco-innovation project “Thermo-vacuum: new process for new generation of thermally modified wood”. The project is part of the 7th Framework Programme for European Research and Technological Development, and thermo-vacuum modified wood is already on the European market. The project was selected by the European Commission, EASME Agency, as "...
M Jebrane, I Cuccui, O Allegretti, N Terziev
Accelerated weathering and fungal resistance of wood modified with isopropenyl acetate
2016 - IRG/WP 16-40764
Chemical modification of Rubberwood (Heveabrasiliensis Müll.Arg) with isopropenyl acetate (IPA) in presence of anhydrous aluminum chloride and iodine as catalysts was carried out. Modified wood surfaces were exposed to UV light source in an accelerated weathering tester to evaluate UV resistance. Anti-swelling efficiency (ASE) and fungal resistance of modified wood were also evaluated. Modified w...
G B Nagarajappa, K K Pandey
Chemical compositions and anti-termite activities of essential oils from Gabonese Canarium schweinfurthii Engl, Dacryodes buettneri Engl and Aucoumea klaineana Pierre wood resins.
2017 - IRG/WP 17-10895
Essential oil extract from resins of Canarium schweinfurthii, Dacryodes buettneri and Aucoumea klaineana woods from Cap Esterias and Oyem areas, Gabon, were prepared by Clevenger - steam distillation. The chemical compositions of these respective essential oils were analyzed by a Gas Chromatography coupled with Mass Spectrometry (GC-MS). Although monoterpenes were the main constituents of the thre...
Chemical compositions and anti-termite activities of essential oils from Gabonese Canarium schweinfurthii Engl, Dacryodes buettneri Engl and Aucoumea klaineana Pierre wood resins.
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
Three-Dimensional Digital Image Correlation of Strains in Profiled Wood Decking Exposed to Wetting & Drying
2017 - IRG/WP 17-20611
We use three dimensional digital image correlation to measure the strains that develop at the surface of profiled radiata pine (Pinus radiata D. Don) deck boards subjected to a wetting and drying cycle. We hypothesise that surface profiling will change the pattern of strain distribution at the surface of deck boards by concentrating stresses at the base of profile grooves. Five groups of three deck board samples were produced from five different pieces of machine stress-graded radiata pine wood. Two wavy profiles, ribble or ripple, were tested. Flat unprofiled boards acted a control. Each board was fixed to a rigid frame and subjected to a wetting and drying cycle. Full field surface strain data was collected using 3D digital image correlation. Strains varied across the surface of both flat and profiled boards. Profiling changed surface strain patterns; strain maxima and minima developed in the profile ridges and grooves during wetting, respectively, but this pattern of strains reversed during drying. Such a pronounced reversal of strains was not observed when flat boards were exposed to wetting and drying, although there was a shift towards negative strains when flat boards were dried. We conclude that profiling changes surface strain distribution in deck boards exposed to wetting and drying, and causes high strains to develop in the grooves of profiled boards. These findings help explain why checks in profiled deck boards are mainly confined to profile grooves where they are difficult to see, and the success of profiling at reducing the negative effects of checking on the appearance of wood decking.
J Mallet, S Kalyanasundaram, P D Evansa
Overview of the treated wood quality control program in the United States with the recent challenges and advances
2017 - IRG/WP 17-20616
In the past two decades, there have been significant and rapid changes in wood protection technologies for residential applications which have moved away from long established heavy duty metal oxide based products such as chromated copper arsenate (CCA). The successor generation of wood protection systems usually contain copper as the primary biocide, in combination with carbon-based co-biocides s...
L Jin
Dimensional Stability of Melamine Formaldehyde-Treated Southern Pine
2017 - IRG/WP 17-40774
The objective of this preliminary study was to evaluate the influence of different levels of melamine formaldehyde (MF) and curing cycle on the dimensional properties of southern pine. Thirty samples for each combination of treatment and curing regimen plus untreated controls and controls subjected to the same curing regimen were tested. Shrinkage/swelling coefficients showed that up to 60% ASE c...
H M Barnes, L S Sites, T S F A França, M G Sanders, F J N França
Accessibility of hydroxyl groups in anhydride modified wood as measured by deuterium exchange
2017 - IRG/WP 17-40784
Acetylated wood shows improved properties largely due to the reduced amount of water in the acetylated cell wall. However, the exact mechanism by which water is excluded in acetylated wood remains unclear. Acetylation reduces hydroxyl content by substitution of hydroxyl groups in wood polymers but may also hinder access to unmodified hydroxyls by physical bulking. This work assesses hydroxyl acces...
G Beck, S Strohbusch, E Larnøy, H Militz, C Hill
The use of new, aqueous chemical wood modifications to improve the durability of wood-plastic composites
2017 - IRG/WP 17-40787
The wood flour used in wood-plastic composites (WPCs) can biologically deteriorate and thus the overall mechanical performance of WPCs decrease when exposed to moisture and fungal decay. Protecting the wood flour by chemical modification can improve the durability of the wood in a nontoxic way so it is not harmful to the environment. WPCs were made with modified wood flour and then evaluated for m...
R E Ibach, C M Clemons, G C Chen
Influence of hygro-thermal treatment temperature and duration on dimensional stabilisation of wood modified with poly(butylene succinate)
2017 - IRG/WP 17-40813
To improve wood properties, especially dimensional stability, a treatment based on poly(butylene succinate) oligomers (OBS) was experimented. After impregnation in wood, a further hygro-thermal treatment (HTT) was carried out in a pressurized reactor at 100% relative humidity (RH) at differing temperatures for differing durations. The aim of HTT is to induce partial swelling of wood cell walls so ...
C Grosse, M Noël, L Rautkari, P Gérardin
A Green and Novel Technology for Recovering Copper and Wood from Treated Wood Waste – Part II: Optimization, copper metal recovery, and process design
2017 - IRG/WP 17-50326
The US consumes 70 million pounds of copper and produces 580 million cubic feet treated wood annually. The EPA disallows burning and reusing treated wood waste due to health/environmental concerns. Vast quantities of copper and wood are landfilled. Two safe and low cost extraction systems, citric acid and ammonium citrate, were identified in Part I of this study. In Part II of the study, effects o...
S Chen, R Patel