Your search resulted in 2994 documents. Displaying 25 entries per page.
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
Barefoot-heat-impact of oil-heat-treated wood: An important thermal property of decking boards
2009 - IRG/WP 09-40458
In this study the phenomenon of sensual heat impression was examined, when walking with bare feet on sun exposed wood based decking boards. A suitable method for measuring the heat flux from decking boards into an artificial foot was developed. The method and measuring device is described as well as results from measuring three different decking board materials: Oil-heat-treated spruce (OHT), untr...
A O Rapp, C R Welzbacher, C Brischke
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
Properties of thermally modified wood of Eucalyptus globulus from Spanish plantations
2009 - IRG/WP 09-40469
This article provides the results of a study about the properties of thermally modified wood of the Southern blue gum (Eucalyptus globulus L.) from Spanish plantations. Although this specie is mainly used for chipping to obtain boards and paper pulp, its high mechanical and strength properties provide great potential for structural use or different solid wood products. A comparison of the properti...
Ó González Prieto, M C Touza
The effect of chemical changes on the wood-moisture relationships in thermally-modified wood
2009 - IRG/WP 09-40473
Small specimens of three wood species were thermally modified following twenty schedules in the 190-245°C temperature range for treatment times between 0.3 and 16 h. Five wood-moisture relations were subsequently determined, namely: anti-swelling efficiency (ASE), movement, hygroscopicity (adsorption and desorption), transversal swelling (radial and tangential directions), and equilibrium moistur...
M M González-Peña, M D C Hale
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
Direct estimation of the durability of high-pressure steam modified wood by ESR-spectroscopy
2010 - IRG/WP 10-40508
Heat generated persistent free radicals have been detected by electron spin resonance measurement of thermally modified wood, prepared by high pressure superheated steam treatment. The specific density of these radicals have been correlated with the durability against basidiomycetes, as measured by the European standard EN113 test. In the lower range of specific radical densities, the found correl...
W Willems, A Tausch, H Militz
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
Testing of decay resistance of sapwood and heartwood of thermally modified Scots pine and Norway spruce
2010 - IRG/WP 10-40523
Thermal modification at elevated temperatures changes the chemical, biological and physical properties of wood. One of the main targets of thermal modification is to increase the biological durability and decay resistance of wood. Although the effects of thermal modification on wood have been widely studied, the significance of sapwood and heartwood on the resistance of thermally modified wood has...
H Viitanen, S Metsä-Kortelainen
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
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
Durability of modified wood in UC3 and UC4. Results from lab tests and 5 years testing in 3 fields
2011 - IRG/WP 11-40562
In 2005 an extensive test program including field tests was set up in order to obtain more data on the durability and long term performance of modified wood and semi-durable wood species. One of the main challenges for modified wood is to predict accurate service life time in UC3 (use class 3, above ground) and UC4 (use class 4, in soil or fresh water contact). So far, data from in-service condi...
M Westin, G Alfredsen
Wet and dry adhesion of coatings on modified and unmodified wood: influence of 18 months of natural weathering on the pull-off test and cross-cut test results
2011 - IRG/WP 11-40569
The objective of this paper is to study the influence of several types of modification (acetylation, furfurylation, heat treatment) on coatings adhesion after 18 months of natural weathering according to EN 927-3 in Vienna (Austria).
The paper compares two methods for assessing the adhesion: the cross-cut test (EN ISO 2409) which is the conventional method used and recommended in EN 927-3 and th...
L Podgorski, G Grüll, M Truskaller, J D Lanvin, S Bollmus
The resistance of thermo and thermo-oil modified black poplar wood (Populus nigra L.) to Basidiomycetes fungi
2012 - IRG/WP 12-40585
The share of area taken by poplar tree species in Poland account for 2.0% of the area of state forests, 4.8% of national parks and for 2.3% in the privately-owned forests. It is shown and expected an increase in the share of poplar stands connected with plantation of fast growing trees. The poplar wood is not resistant to Basidiomycetes fungi, easy attacked by insects and in consequence is regarde...
A Fojutowski, A Kropacz, A Noskowiak