Your search resulted in 457 documents. Displaying 25 entries per page.
The durability of natural and thermomodified black poplar wood and Scots pine sapwood after two years of external exposition
2016 - IRG/WP 16-40730
Natural biological durability of many European wood species is considered to be relatively small, particularly in a ground contact conditions. This is due to the exposure of the wood to the range of biological and atmospheric destructive factors. This may to limit the scope of application of the wood of these species, particularly in construction. The biocides are often used for wood protection in...
A Fojutowski, A Kropacz, A Noskowiak
Formation of hydrophobic wood surface by means of thermal treatment and surface modification with alkyl ketene dimer (AKD)
2016 - IRG/WP 16-40738
One of the major shortcomings of wood-based materials compared to technical materials is attributed to their poor dimensional stability in changing climates and in contact with liquid water. Heat treatment induces chemical change with a consequent decreasing of reactivity of the material showing unwanted surface inactivation. Alkyl ketene dimer (AKD) is a widely used sizing agent in papermaking, w...
T Lovaglio, T Meints, L Todaro, W Gindl-Altmutter
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
Durability of Thermally Modified Engineered Wood Products
2016 - IRG/WP 16-40745
In this study, rated plywood, oriented strand board (OSB), laminated strand lumber (LSL), and laminated veneer lumber (LVL) were thermally modified as a post-treatment at 140 °C, 150 °C, 160 °C, 170 °C, and 180 °C using a closed, pressurized treatment method. Eastern larch OSB manufactured from heartwood and sapwood was also thermally modified as a post-treatment at 160 °C and 180°C. All ...
H M Barnes, M D Aro, A Rowlen
The influence of log soaking temperature and thermal modification on the properties of birch veneers
2016 - IRG/WP 16-40749
In veneer manufacture the logs are routinely soaked in heated water baths in order to soften the wood prior to peeling. The temperature of the water may vary greatly between batches; however, the influence of log soaking temperature on veneer properties has had little research attention. Uncontrolled moisture is known to cause problems in wood-based materials, while thermal modification offers a m...
S Källbom, K Laine, M S Moghaddam, A Rohumaa, K Segerholm, M Wålinder
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
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
Weathering protection of European hardwoods through double modification
2017 - IRG/WP 17-30715
Beech and poplar were thermally modified, treated with melamine resin and both treatments were combined. The weathering performance (cracks and general appearance) of modified beech and poplar was assessed in natural weathering and correlated to material properties such as work in bending (WB) and Brinell hardness. In addition, the equilibrium moisture content after exposure of 12 months and subse...
G Behr, A Gellerich, S Bollmus, H Militz
Effects of heat treatment on sound absorption coefficients in nanosilver-impregnated and normal solid woods
2017 - IRG/WP 17-40770
Effects of impregnation with silver nano-suspension as well as heat-treatment on sound absorption coefficients (AC) were studied in tangential direction of five different solid woods based on their importance. AC was measured at two frequencies of 250 and 500 Hz. A 400 ppm nanosuspension was used for the impregnation; silver nanoparticles had a size range of 30-80 nm. Based on the obtained results...
A Esmailpour, J Norton, H R Taghiyari, H Zolfaghari, S Asadi
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
Studying Weathering Performance of Coatings on Thermally Modified Wood
2017 - IRG/WP 17-40805
Thermal modification and degree of improved properties depends on wood species and treatment parameters. Southern pine and spruce are the two common wood species for decking, fences and siding in North America. This study was the first to evaluate coating performance when applied on oil-heat-treated southern pine and spruce wood samples. Water uptake, colour and gloss changes of samples were analy...
M Nejad, M Dadbin, P Cooper
Impact of heat treatment on physico-mechanical properties of torrefied Antholceistha djalonensis wood
2017 - IRG/WP 17-40811
Thermal modification at relatively high temperatures is an effective method to improve the dimensional stability and mechanical properties of wood. This study was carried out to investigate the impact of heat treatment on the physic-mechanical properties of torrefied Anthocleistha djalonensis wood. Thirty nine defect-free specimens of dimensions 20 mm × 20 mm × 60 were prepared for the determina...
E A Iyiola, B Olufemi, J A Fuwape, J M Owoyemi
Understanding of the effect of ancestral and natural saltwater treatment on durability, fibers densification and chemical modification of palm wood
2018 - IRG/WP 18-10921
The palm-tree sector plays a very important role on both the socioeconomic and ecological levels, in Tunisia. There are three million trees in Tunisian palm plantations, ensuring a potential significant wood production, mainly in the craft and furniture industries.
In the past, Date Palm wood (Phoenix dactylifera L.,) was also used as structural material. Its low natural durability and its low m...
M T Elaieb, A Namsi, M Tella, M-F Thévenon, K Chandelier
FTIR-ATR monitoring of chemical changes of thermo-chemically modified beech wood degraded by brown-rot fungus
2018 - IRG/WP 18-40823
Wood chemical modification with lactic acid oligomers (OLA) has been reported to confer promising properties for wood outdoors applications. To better understand the lactic acid interaction with wood, chemical changes following biological degradation have been characterized with a battery of tests. Fourier transform infrared (FTIR) spectroscopy has been proved to be a valuable tool for studying fu...
C Grosse, M Noël, M-F Thevenon, P Gérardin
Long-term performance of DMDHEU-treated wood exposed in ground, above ground and in the marine environment
2018 - IRG/WP 18-40825
Chemical wood modification with N-methylol compounds such as 1.3-dimethylol-4.5-dihydroxyethyleneurea (DMDHEU) has been studied intensively since the 1990s. Research of the past years focused on treatment of Scots pine (Pinus sylvestris L.) and European beech wood (Fagus sylvatica L.) and was shown to be applicable to improve specific material properties. A high resistance against wood-destroying ...
L Emmerich, H Militz, C Brischke
An examination of the potential for the use of the Maillard reaction to modify wood
2018 - IRG/WP 18-40829
Finding efficient ways to decrease wood decay caused by fungi and increasing its dimensional stability is an important issue in the timber construction. A possible way to avoid wood decay by fungi is by reducing the water content of wood, since water is a primary condition for fungal growth. Bulking of the wood cell wall by chemical reagents occupies the space where water normally occurs. At the s...
K Peeters, E Larnøy, A Kutnar, Č Tavzes, C A S Hill
Improvement of short rotation teak wood properties through thermal modification
2018 - IRG/WP 18-40842
Teak (Tectona grandis L.f) is one of the most popular tropical timber species. Nowadays, the source of long rotation teak is limited in the availability. Many wood processing industries use short rotation teak, which has lower quality especially in durability and dimensional stability. Heat treatment is an eco-friendly method improving dimensional stability and durability of wood. The objectives o...
L A Pratiwi, I W Darmawan, B George, A Merlin, C Gérardin, S Dumarçay, T Priadi, P Gérardin
Developments within COST Action FP1303 related to the modification of wood
2018 - IRG/WP 18-40847
COST Action FP 1303 (Performance of bio-based building materials) was established in 2013 with the main aim to improve the knowledge on the performance of bio-based materials used as building products and the assessment of factors influencing these, with the aim of increasing their service life. This Action has helped in understanding the interlinked relationships between durability, product aesth...
D Jones
Study on the ability of wood-destroying fungi to grow through chemically modified wood
2019 - IRG/WP 19-40858
Over the last decades, chemical wood modification technologies were developed to increase the resistance against attack by wood-destroying organisms without using biocides. Most of those technologies are based on an impregnation step initially. In most treated wood products, mainly by using solid wood in thicker dimensions as in posts, poles, sleepers, deckings etc. it is known that wood impregnat...
L Emmerich, S Strohbusch, C Brischke, S Bollmus, H Militz
An overview of recent studies involving the thermal modification of hardwood species
2019 - IRG/WP 19-40869
This paper outlines recent activities related to the thermal modification of hardwood species, and particularly to tropical hardwood species. Timber demand is ever increasing, but this is being limited by the necessity to protect virgin forest stands. As such, the majority of supply of popular species is being met from juvenile short rotation stands. The limited age from these stands often plays a...
D Jones, M Gaff, F Kacik
Charring of Norway spruce wood surface – an alternative surface modification technique?
2019 - IRG/WP 19-40870
Charring is an old wood surface treatment technique, mainly performed on wooden façade elements with the aesthetical aims, but also with the purpose of protection. This flame treatment method can be grouped into heat treatment processes. Below the top charred layer of damaged wood there is a layer which is during flame treatment exposed to high temperatures in anoxic or semi-anoxic conditions. Th...
M Petric, M Pavlic, J Zigon
Improvement of wood decay and termite durability resulting from combined treatments based on borax/phenol-formaldehyde impregnation followed by thermal modification
2019 - IRG/WP 19-40871
This study determined the factors influencing the boron content after leaching of pine blocks impregnated with aqueous solution of phenol-formaldehyde (PF) resin with or without borax and subjected to heat treatment by response surface methodology. An experimental design permits to analyze the effects of heat treatment temperature (150, 185 and 220°C), curing time (5, 12, 5 and 20 hours), resin c...
S Salman, M-F Thevenon, A Petrissans, S Dumarcay, P Gerardin
Water interactions in wood polyesterified with sorbitol and citric acid
2020 - IRG/WP 20-40888
Polyesterifcation of wood with sorbitol and citric acid seems to be a promising chemical wood modification technique that is both low-cost and produced from bio-based chemicals. An interesting aspect of the modification is the interaction of water with the polyesterified wood since the relationship with moisture appears to be unique compared to other wood modification systems. This communication p...
G Beck, A Treu, E Larnøy
NewSiest-Enhancement of UV stability of thermally modified wood through envelope impregnation with nanobased stabilisers
2020 - IRG/WP 20-40909
Thermal modification is a process which improves the properties of wood, resulting in a material that can be disposed at the end of the product life cycle without presenting an environmental hazard. Thermally modified wood retains as a natural product and the grain, original colour variances and characteristics of wood are still present. However, exposure to daylight causes brightening or greying ...
K Srinivasa, M Petrič