Your search resulted in 336 documents. Displaying 25 entries per page.
Development of a quality control assessment method to predict properties of heat treated wood
2012 - IRG/WP 12-40611
Heat treatment has been used to improve properties of non durable European species. Chemical modification of some of the wood components provides improved dimensional stability and biological performance against decay fungi while mechanical properties such as modulus of rupture are reduced. Quality control of commercially made thermally treated wood is one of the major challenges to allow its indu...
M Chaouch, K Candelier, S Dumarcay, A Pétrissans, M Pétrissans, P Gérardin
Differences between heat treated Pinus pinaster heartwood and sapwood
2012 - IRG/WP 12-40617
Heat treatment is a well known process to improve the durability and dimensional stability of less noble woods. The treatment can be applied for heartwood unlike the traditional treatments based on impregnation due to the difficulty of impregnating heartwood.
Pure sapwood and pure heartwood samples were treated in an oven at 190ºC and 200ºC for 2h, 4h and 6h. Dimensional stability, measured a...
B Esteves, L Nunes, I Domingos, H Pereira
The activity of a wood-decaying fungus during drying and rewetting cycles measured by isothermal calorimetry
2013 - IRG/WP 13-20526
Wood decaying fungi are an essential part of any ecosystems as they are the main decomposers of cellulose and lignin-containing materials. But as wood is a common building material the risk for decay fungi growth and subsequent degradation of our construction material is a concern. There are important physiological aspects of the growth and activity of decay fungi that are unknown today, and witho...
S Johansson, L Wadsö, A Pilgård, G Alfredsen
Performance testing of DMDHEU-modified wood in Australia
2013 - IRG/WP 13-30613
Chemical wood modification with dimethyloldihydroxy-ethyleneurea (DMDHEU) or its derivatives has been researched for many years and shown to be applicable to improve certain wood properties to both solid lumber and wood-based composites. Earlier research proved a high biological resistance of DMDHEU-modified wood against biological degradation in laboratory and field tests in Europe. Due to the ve...
H Militz, J Norton
Hygroscopicity of wood after polyethylene glycol (PEG) impregnation and/or heat treatment
2013 - IRG/WP 13-40623
The hygroscopicity of wood after polyethylene glycol (PEG) impregnation and/or heat treatment was investigated by testing the water uptake, equilibrium moisture content (EMC) at various relative humidity levels, and contact angle of the poplar wood surface. The results showed that: (1) At the first moment, the heat treatment at temperatures lower than 160 ℃ did not reduce the water uptake be...
Weiyue Xu Yuan Zhu, Jinzhen Cao
Decay resistance of thermally modified Scots pine after 6 years’ exposure above ground
2013 - IRG/WP 13-40624
In the present study the performance of boards treated by ThermoWood process were studied above ground and the results given are based on a “modified” horizontal double- layer test. The base layer of boards was in direct contact with ground and the conditions were much harder than in the standard method. After six years’ exposure clear differences were found between untreated Scots pine and ...
H Viitanen, S Metsä-Kortelainen, A Nurmi, S Jämsä
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
Combined effects of thermal modification and ACQ-D impregnation on properties of southern yellow pine wood
2013 - IRG/WP 13-40637
In this study, samples of southern yellow pine sapwood were first thermally modified and then treated by the alkaline copper quat-type D (ACQ-D) wood preservative. Two heating temperature (180℃ and 220℃) and two concentrations of ACQ-D solution (0.9% and 1.35%) were used in the experiments. The combined effects of thermal modification and ACQ-D on leaching performance, mechanical prope...
Wang Wang, Yuan Zhu, Jinzhen Cao
Influence of Heat Treatment Medium on Fungal Resistance of Beech Wood
2013 - IRG/WP 13-40643
Hydrothermal treatment of beech wood (Fagus orientalis) performed in acidic, neutral and alkaline buffered mediums in 160 and 180°C. White rot fungi (Coriolus versicolor) and brown rot fungi (Coniophora puteana) were used to determine the influence of heat treatment mediums on the behaviour of fungal resistance. White rot of wood digest lignin rather than cellulose; while brown rot digests the ce...
A Talaei, A Karimi, M-F Thévenon
Effect of bio-resin from cashew nut shell liquid (CNSL) on decay resistance properties of wood
2013 - IRG/WP 13-40649
This study assesses the decay resistance properties of bio-resin modified wood against decay fungi of the Basidiomycota according to the EN 113 protocol. A bio-resin system was developed by ozonolysis process from cashew nut shell liquid (CNSL), a naturally occurring mixture of phenolics. Small wood blocks from sapwood of Scots pine (Pinus sylvestris), Obeche (Triplochiton scleroxylon) and Gmelina...
M Ashaduzzaman, M D Hale, V Tverezovskiy, G A Ormondroyd
Protein extraction from wood decay fungus Postia placenta
2014 - IRG/WP 14-10827
Wood decay fungi (often distinguished as white rot and brown rot) belonging to the basidiomycetes, are common inhabitants of forest litter, where they play an important role in carbon cycling. Brown rot fungi are perhaps the most important organism involved in the degradation of wood products, and of considerable economic importance. Brown rotted wood loses strength very early because of the rapid...
A Pilgård, P Arnold, K Richter
Effect of silver nanoparticles on the rate of heat transfer to the core of the medium-density fiberboard mat
2014 - IRG/WP 14-40653
Effect of silver nanoparticles on the rate of heat transferred to the core section of medium-density fiberboard (MDF) mat was studied here. A 400 ppm aqueous nanosilver suspension was used at three consumption levels of 100, 150, and 200 mL/kg based on the weight of dry wood fibers; the results were then compared with the control MDF panels. The size range of silver nanoparticles was 30-80 nm. Res...
H Reza Taghiyari, O Schmidt, E Bari, P M Tahir, A Karimi, P Nouri, A Jahangiri
Termite resistance of wood modified with short- and long-chain siloxanes
2014 - IRG/WP 14-40660
Scots pine (Pinus sylvestris L.) sapwood specimens modified with short- and long-chain amino-functional siloxane emulsions were exposed to subterranean termites (Reticulitermes flavipes Kollar). Laboratory choice and no-choice tests following the standard EN 117 (2013) were conducted for 8 weeks in order to evaluate the influence of these silicon-based compounds on the termite resistance of treate...
P Gascón-Garrido, M-F Thévenon, H Militz, C Mai
Effects of thermal modification on properties of Douglas-fir heartwood
2014 - IRG/WP 14-40663
The flexural properties and mass losses of thermal modified Douglas-fir pretreated with boron or glycerol were examined. Pretreatments were associated with slight, but not significant, reductions in modulus of rupture (MOR) and modulus of elasticity （MOE）of Douglas-fir at different thermal treatment levels. Boron pretreatment had the greatest effect on MOR. MOR of non-pretreated and ...
Li Yan, J J Morrell
Improving dimensional stability of thermally treated wood by secondary modification – potential and limitations
2014 - IRG/WP 14-40664
The potential of treating thermally modified wood with melamine resin to improve the dimensional stabilization is tested in this research. Two different boards of poplar (Populus ssp.) were cut into two halves. One half of each board was thermally modified (T1 and T2) in a commercial process, the other half was used as untreated reference material. The material was thermally modified using the vac...
G Behr, K-C Mahnert, S Bollmus, H Militz
Development of new wood treatments combining boron impregnation and thermo modification - Effect on decay and termites durability
2014 - IRG/WP 14-40666
Environmental pressures appeared in most European countries during the last decade has lead to the development of more environmentally acceptable preservation methods. In this context, wood heat treatment has been one of the most investigated alternative methods during the last years. Treated at temperatures ranging between 180 and 220°C, wood components undergo more or less important chemical mo...
S Salman, A Pétrissans, M-F Thévenon, S Dumarçay, B Pollier, P Gérardin
Performance of some wood modification treatments against marine borers
2014 - IRG/WP 14-40668
Since some years, new treatment technology to protect wood against wood destroying fungi is introduced. Limited knowledge on their resistance to water organisms is available. Therefore, the resistance of chemically modified wood was assessed in a field test according to the European Standard EN 275 over a period of 3 resp. 5 years at sites in the North Sea and the Baltic Sea. Scots pine (Pinus syl...
A Klüppel, C Mai, H Militz, S Cragg
Possible targets of wood modification in brown rot degradation
2014 - IRG/WP 14-40676
Wood modification protects wood from fungal degradation in a non-toxic manner. However, the mechanisms behind the decay resistance in modified wood are currently unknown. The aim of this study was to discuss the i) colonisation, ii) nutrient recognition, iii) transcription, iv) depolymerisation and v) hydrolysis steps in the brown rot degradation progress and explore whether they are inhibited by ...
R Ringman, A Pilgård, G Alfredsen, B Goodell, K Richter
The Physical Properties of Heat Treated Fir Wood and Outdoor Durability
2014 - IRG/WP 14-40677
Wood might be easily susceptible to degrade by biotic and abiotic factors. Therefore, wood should be protected from fungi, insects and other degradation factors by applying treatment methods. Especially, for the wood have used in the external environment. Chemical treatment methods have some disadvantages such as use of toxic chemicals (Arsenic and chromium) and treatability of refractory wood spe...
O E Özkan, H Vurdu, A Temiz, G Köse
Lignin Modification to Produce Sustainable Polyurethane Resin for Wood Coatings
2014 - IRG/WP 14-40682
The use of lignin as the most abundant aromatic natural polymer has been evaluated for use in the production of lignin-based polyurethane resin for coating applications. Coatings are made of resins (ca. 50%), which today are mainly derived from petroleum-based polymers. This study is focused on the development of an environmentally friendly method of modifying lignin to be used as source of natura...
M Nejad, M Arefmanesh, S Chandra, J Mostaghimi, E Master
A review of the analytical methods used in determining the decay resistance of heat treated wood
2015 - IRG/WP 15-40690
Heat treatment as a wood process is increasingly used because of its non-biocide behaviour and its low environmental impact. This sort of treatment is based on biopolymer chemical degradation by heat transfer. This process improves mainly the dimensional stability and the decay resistance of wood.
Wood becomes darker after this type of treatment and thus gives it an aesthetic appearance. These i...
K Candelier, M-F Thévenon, A Pétrissans, S Dumarçay, P Gérardin, M Pétrissans
Effect of natural variability of European Oak wood on heat treatment process and potential implication on wood durability
2015 - IRG/WP 15-40693
Environmental pressures appeared in France and in most European countries during the last decade has led to the development of more environmentally acceptable preservation methods. In this context, wood heat treatment has been one of the most investigated alternative method during the last years. Treated at temperatures ranging between 180 and 220°C, wood components undergo more or less important...
J Hamada, A Pétrissans, F Mothe, M Pétrissans, P Gérardin
A novel enzymatic treatment as a new approach for wood protection
2015 - IRG/WP 15-40701
Wood durability is a worldwide concern and most treatments tend to fail with regard to their efficacy along the time. Weather conditions lead to a loss of the treatment substances into the surrounding environment and, in consequence, generate also a public health concern.
Recently, the employment of oxidative enzymes, such as laccases, has been proposed as a tool for lignocellulosics modificatio...
C Fernández-Costas, S Palanti, M Ángeles Sanromán, D Moldes