Your search resulted in 3057 documents. Displaying 25 entries per page.
Preliminary investigation of biological resistance, water absorption and swelling of thermally compressed pine wood panels
2008 - IRG/WP 08-40396
Wood can be modified by compressive, thermal and chemical treatments. Compression of wood under thermal conditions is resulted in densification of wood. This study evaluated decay and termite resistance of thermally compressed pine wood panels at either 5 or 7 MPa and at either 120 or 150?C for one hour. The process caused increases in density and decreases in thickness of the panels; however, lab...
Ö Ünsal, S N Kartal, Z Candan, R Arango, C A Clausen, F Green III
Resistance against basidiomycetes of 1,3-dimethylol-4,5-dihydroxy ethylene urea (DMDHEU)-modified plywood of Pinus sylvestris
2008 - IRG/WP 08-40398
Plywood produced with rotary-cut veneers of Pinus sylvestris impregnated with a solution of 1.3 M 1.3-dimethylol-4.5-dihydroxyethyleneurea (DMDHEU) and glued with a phenolic resin (Prefere 4976 DYNEA) were inoculated with Coniophora puteana, Coriolus versicolor and Pleurotus ostreatus, following the European standard ENV 12038. The specimens were leached following European standard EN 84. The re...
A Dieste, A Pfeffer, S Bollmus, H Militz
Wood plastic composites from modified wood. Part 3. Durability of WPCs with bioderived matrix
2008 - IRG/WP 08-40423
The decay resistance of fully bio-derived wood plastic composites, WPCs, was tested in both laboratory and field tests. The laboratory tests were performed according to modified versions of AWPA E10 (soil-block test) and ENV 807 (tests in three un-sterile soils) and the field tests according to EN 252 (stakes in ground) and EN 275 (resistance to marine borers). The WPC materials for laboratory tes...
M Westin, P Larsson Brelid, B K Segerholm, M Van den Oever
Ecotoxicity of furfurylated wood – Effect of leachate on aquatic bacteria
2008 - IRG/WP 08-50250
Environmental concern regarding the use of toxic preservatives such as CCA (chromated copper arsenate) has been put forward. In the EU, USA and Japan, CCA is now phased out for residential use and for use in water contact. Several ecotoxicological studies of wood treated with conventional preservatives were carried out in the late 1990s. In these studies it was concluded that the main impact is to...
A Pilgård, M Westin
The resistance of thermo-oil modified wood against decay and mould fungi
2009 - IRG/WP 09-40448
Thermally modified wood in comparison to natural wood demonstrates some advantageous functional properties like decreased hygroscopicity, higher dimensional stability. It also has increased durability and improved resistance to fungal decay. However thermal modification of wood may lead to reduced strength properties what may limit the use of wood in mechanically beared constructions. The changes ...
A Fojutowski, A Kropacz, A Noskowiak
Termite resistance of some modified wood species
2009 - IRG/WP 09-40449
During the last few decades, researchers worldwide have investigated and developed new treatment techniques to improve intrinsic wood properties. Some of these techniques were introduced to the market recently and are gaining in importance.. Various wood properties of these new materials have been studied intensively. These include physical-mechanical properties (dimensional stability, moisture ...
H Militz, B C Peters, C J Fitzgerald
Wettability and bonding strength of wood thermally-treated with different combinations of soy oil and chemical additives
2009 - IRG/WP 09-40454
Thermal treatment is a method which has gained wider acceptability as an alternative to the chemical treatment in wood preservation. In order to maximize the benefits of this technique several options have been adopted including the use of soy oil in transferring the heat to the wood. Available information on thermal treatment in general and the oil method in particular show that there are still n...
L Awoyemi, P A Cooper, T Ung
Estimating the heat treatment intensity through various properties of thermally modified timber (TMT)
2009 - IRG/WP 09-40459
The suitability of different measures for prediction of the heat treatment intensity was investigated. Therefore, the resistance to impact milling (RIM), the lightness L*, the equilibrium moisture content (EMC), the anti swelling efficiency (ASE) and the total amount of soluble carbohydrates (TSC) of heat treated specimens were correlated with corresponding fungal resistance achieved by heat treat...
C R Welzbacher, C Brischke, A O Rapp
Weathering of Wood Modified with the N-Methylol Compound 1,3‑dimethylol-4,5-dihydroxyethyleneurea (DMDHEU)
2009 - IRG/WP 09-40467
Scots pine (Pinus sylvestris L.) sapwood boards were treated with a methylated 1,3‑dimethylol-4,5-dihydroxyethyleneurea (mDMDHEU) causing weight gains of approx. 25% and exposed to weathering for 18 months. Compared to untreated boards, treatment with mDMDHEU reduced surface discoloration mainly caused by staining fungi. Boards treated with mDMDHEU exhibited clearly lower moisture content th...
C Mai, Yanjun Xie, A Krause, K Urban, P D Evans, K Richter, H Militz
Physical and Mechanical Properties of Hydrothermally Modified Mulberry (Morus alba L.) Wood
2009 - IRG/WP 09-40481
This research was carried out to investigate influences of hydrothermal modification on physical and mechanical properties of mulberry wood that is used for musical instruments in Iran. Samples of mulberry wood were cut into size of 20x20x360 mm and placed in a water filled stainless steel cylinder and treated at temperatures of 100, 120 and 140ºC for 1 and 5 hours. Treated samples were subjected...
A Talaei, K Yaghoobi
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
Early detection of colonisation by blue stain and mould on modified wood using PCR technique
2010 - IRG/WP 10-10730
The aim of this research was the early detection of fungal attack on the surfaces of modified and unmodified wood after natural weathering. The investigation was carried out by molecular techniques and the development and establishment of genus/species specific PCR for important moulds and sapstain fungi was part of this work. After adaption of the method, a monitoring of the succession of Ascomyc...
A Steitz, B Schmöllerl, N Pfabigan, S Bollmus, G Grüll
Mould growth on wood-based materials – a comparative study
2010 - IRG/WP 10-20455
Ten different wood-based materials - preservative-treated wood, fire retardant-treated wood, modified wood, WPCs and untreated references of pine sapwood and spruce - were tested for mould growth according to SP method 2899 during 42 days at 90% RH and 22°C.
Even though the results must be interpreted carefully, they indicate significant differences in mould resistance between the materials tes...
P Johansson, J Jermer
Performance of selected types of coated and uncoated modified wood in artificial and natural weathering
2010 - IRG/WP 10-40510
The objective of the present work was to investigate the influence of commercial wood modification methods on weathering behaviour and coating performance. It was aimed to compare modification methods and to set up maps of weathering behaviour for these methods with and without a semi-transparent wood stain. Artificial and natural weathering trials were carried out with a selection of different ty...
G Grüll, L Podgorski, M Truskaller, I Spitaler, V Georges, S Bollmus, A Steitz
Study of Microscopy Properties of Modified Wood During Weathering Process
2010 - IRG/WP 10-40517
In this study spruce (Picea excelsa) and Beech (Fagus orientalis) wood acetylated and has been subjected of artificial weathering in difference times (0, 50,150&300 h), then wood surface analyzed using Scanning Electron Microscopy (SEM). The SEM results shown that the surface of wood exposed to weathering undergoes distinct physical changes and the surface degradation appears to be directly propor...
M Akhtari
Acquisition of sorption isotherms for modified woods by the use of dynamic vapour sorption instrumentation: Principles and Practice
2010 - IRG/WP 10-40518
The complex wood-water relationship has been the topic of numerous studies. Sorption isotherms – in particular – have been derived for hundreds of wood species, their sap- and heartwood sections as well as for decayed, engineered and modified wood materials. However, the traditional methods for obtaining sorption isotherms are very time consuming. With new dynamic vapour sorption (DVS) instrum...
E T Engelund, M Klamer, T Mark Venås
Wet and dry adhesion of coatings on modified and unmodified wood: comparison of the pull-off test and the cross-cut test
2010 - IRG/WP 10-40524
The objective of this paper is to study the influence of several types of modification (acetylation, furfurylation, thermal modification) on coatings adhesion and to compare two methods of assessing the adhesion: the cross-cut test and the pull-off test both tested in dry and wet conditions. The study also investigates the effect of other parameters of the wood substrates on adhesion like the ring...
L Podgorski, G Grüll, M Truskaller, J D Lanvin, V Georges, S Bollmus
Molecular investigation of Postia placenta growing in modified wood
2011 - IRG/WP 11-10756
Brown rot is the most common and destructive type of fungal decay for wood in service. These fungi depolymerize preferentially the structural carbohydrates, cellulose and hemicellulose in the cell wall leaving oxidized lignin behind. Modified wood can provide protection against a variety of wood deteriorating organisms, including decay fungi. However, there is still little known about the mode of ...
B Schmöllerl, G Alfredsen, C G Fossdal, M Westin, A Steitz
Aesthetic service life of coated and uncoated wooden cladding - influencing factors and modelling
2011 - IRG/WP 11-20470
Mould growth on exterior coated cladding façades is an undesirable element and will often shorten the aesthetical service life. Mould growth on painted surfaces is influenced by type and concentration of film fungicides, the paint formulation and the wood substrate itself, and wooden cladding may experience exponential fungal deterioration caused by variation in the climatic factors, often within...
L Ross Gobakken, O A Høibø
Slice - Cut and Analyze Laser Microdissection (LMD): A method to produce sample material from modified wood for chemical quality analysis
2011 - IRG/WP 11-20478
Wood modification with its various systems is an established way to enhance a wood products’ service life in outdoor applications. Per definition, selected material properties are enhanced by means of modification without producing toxic substances or residues during service life and combustion afterwards. The systems of impregnation modification include a physical and often chemical alteration ...
K Zimmer, E Larnøy, A Treu, M Fongen
Effect of P/F ratio, PF concentration and treating method on boron leaching from wood treated with PF modified boron compounds
2011 - IRG/WP 11-30559
In order to immobilize boron in wood, three kinds of resol-type phenol-formaldehyde (PF) resin with different P/F ratios were synthesized in laboratory and incorporated with three types of boron compounds to treat wood. The used boron compounds included boric acid (BA), borax (BX) and disodium octaborate tetrahydrate (DOT). The leaching test of boron from wood blocks was performed according to the...
Liping Yu, Jinzhen Cao
Acetylation Properties of Southern Pine and Radiata Pine
2011 - IRG/WP 11-40543
The chemical modification of wood via acetylation with acetic anhydride has been a well investigated technology and is of current commercial interest due to improved properties such as dimensional stability as well as resistance to termites and resistance to rot and decay fungi. Despite this, the acetylation of a board substrate requires further investigation in order to assess board properties a...
J Allen, T Guinn, J Dickerson
Thermally modified timber (TMT) for decking applications – determination of relevant surface properties
2011 - IRG/WP 11-40544
In recent years thermally modified timber (TMT) entered various market segments. It is used for facades, horticultural equipment, garden furniture, and also for kitchen and bathroom cabinets. However, flooring turned out to be the most important application for TMT, either as interior parquet or as exterior decking. Besides durability and dimensional stability, which had been the initial target pr...
L Meyer, C Brischke, C R Welzbacher
Physical properties of Pinus radiata veneers modified with hexamethoxymethyl melamine prepolymers
2011 - IRG/WP 11-40551
Prepolymers containing hexamethoxymethyl melamine and either sucrose (Suc-HMMM) or polyvinyl alcohol (PVA-HMMM) were prepared by acid catalysis under reaction conditions optimised with respect to stiffening effect when introduced into Pinus radiata veneers by vacuum impregnation and cured by hot pressing at 150C. Maximum increases in MOE were 20% for Suc-HMMM (50% WPG), 22% for PVA-HMMM (...
C Molloy, W Rae, S Connor, T Henderson, A Siraa
Biological properties of Pinus radiata veneers modified with hexamethoxymethyl melamine
2011 - IRG/WP 11-40552
An investigation of the effects on decay and termite resistance of a wood modification process involving prepolymers of hexamethoxymethyl melamine (HMMM) was conducted using LVL as a model engineered wood product. Dry Pinus radiata veneers were vacuum-impregnated with a wood modification formulation containing a mixture (P-H:S-H) of two separate prepolymerisation reactions containing polyvinyl al...
A Siraa, S Millward, C Molloy