Your search resulted in 3057 documents. Displaying 25 entries per page.
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
Decay resistance variability of European wood species thermally modified by industrial process
2017 - IRG/WP 17-40807
Thermal modification is now considered as a new ecofriendly industrial wood modification process improving mainly the material decay resistance and its dimensional stability. Most industrial thermal treatment processes use convection heat transfer which induces sometimes heterogeneous treatment temperature propagation within the oven and lead to the heterogeneity in treatment efficiency. Thus, it ...
K Candelier, L Pignolet, S Lotte, A Guyot, E Cuny, B Bousseau, M-F Thévenon
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
Aesthetic changes of coated thermally modified wood after artificial weathering
2017 - IRG/WP 17-40819
The thermal modification process affects the chemical configuration of the wood matrix improving some physical properties and durability. In addition, the distinctive dark tones of thermally modified timber increase the economic value of several light-coloured species. However, heat-treatment alters the substrates and it could influence in the application of coating products, necessaries to mainta...
R Herrera, J Sandak, E Robles, J Labidi
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
Resistance of modified wood to termite attack assessed in laboratory and field testing: A review of internal research
2018 - IRG/WP 18-40824
Within the past decades, new wood modification technologies have been investigated in order to improve certain wood characteristics and enable the use of timber products for outdoor applications. Some of these non-biocidal technologies have been developed and commercialized recently. Thus, various material properties were studied intensively and shown to be improved. To a great extent, previous re...
L Emmerich, P Gascón-Garrido, H Militz
Hydroxyl accessibility - A brief review of deuterium exchange studies on modified wood
2019 - IRG/WP 19-20656
Wood modification imparts dimensional stability and decay resistance. The mechanism(s) by which this occurs are thought to be related to the bulking of the wood cell wall and subsequent moisture exclusion. Hence, quantification of accessible hydroxyl (OH) groups is of great interest when evaluating and increasing the understanding of the performance of modified wood. The aim of this study was to b...
G Beck, C Hill, G Alfredsen
Durability classification of preservative treated and modified wood
2019 - IRG/WP 19-20659
EN 350 (2016) allows formally to determine durability classes (DC) for wood products and wood-based materials, which was previously only possible for untreated wood in the form of natural durability. In a first study, the University of Goettingen carried out the durability classification of chemically modified (modified with 1,3-dimethylol-4,5-dihydroxyethyleneurea, DMDHEU) and preservative-treate...
S Bollmus, L Bachle, C Brischke, H Militz
Performance of modified wood in service - multi-sensor data fusion and its multi-way analysis
2019 - IRG/WP 19-20660
Recent developments in the field of electronic sensors and analytics provide new opportunity for accurate characterization of materials often based on portable and non-destructive methods. By using several complementary techniques, the material description is precise and complete. The data provided by multiple equipment, however, are often not directly comparable due to different resolution, sensi...
A Sandak, J Sandak, M Cocchi
Using X-ray scattering to elucidate the mechanisms behind the moisture and fungal decay resistance of epoxybutene modified wood
2019 - IRG/WP 19-40854
Chemical modification of the hydroxyl groups of wood can improve the properties of wood by providing moisture and biological resistance, as well as dimensional stability. Southern pine solid wood was chemically modified to various weight percentage gains (WPG) with epoxybutene (EpB, 8%-38% WPG). After modification, specimens were extracted with a toluene: ethanol (2:1) solution for 2 hours or wate...
R E Ibach, N Plaza
Dimensional stability and decay resistance of montmorillonite- furfuryl alcohol modified wood
2019 - IRG/WP 19-40856
Poplar (Populus cathayana) wood was impregnated successively by organo-montmorillonite (OMMT; in concentration of 2%) and furfuryl alcohol (FA, in concentrations of 15%, 30% and 50%) in a two-step method to prepare OMMT-FA modified wood. The modified wood samples were characterized using X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). Moreover, wood physical and a...
L Zhang, J Cao
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
The anti-weathering mechanism of extractives in thermally modified Scots pine
2019 - IRG/WP 19-40880
Results from the electron spin-resonance spectroscopy (ESR) analysis indicated that thermally modification of wood can inhibit the generation of phenoxyl radicals during UV irradiation and consequently lead to the increase of the color stability of wood. In order to clarify the evolution and role of extractives in thermally modified wood during the process of weathering, the compositions of aceton...
H Shen, J Cao
Studying amount, location and state of water in modified wood at moisture levels relevant for fungal degradation
2020 - IRG/WP 20-40889
Water is an essential parameter for fungal degradation of wood, but degradation primarily occurs at high moisture levels at water potential in the range of -4 to -0.1 MPa, which corresponds to 97-99.9% relative humidity. At these moisture levels, water is present in the wood structure both in and outside of cell walls. The majority of previous studies on the interaction between wood and water for ...
M Fredriksson, E Engelund Thybring, Ramunas Digaitis
Elucidation of reactive sites of wood modified with acetic anhydride: Insights from density functional theory calculations
2020 - IRG/WP 20-40892
Density functional theory (DFT) was employed to investigate the interaction of cellulose and lignin with acetic anhydride for explaining the wood modification process. Atoms in molecules (AIM) and reduced density gradient (RDG) along with non-covalent interaction (NCI) plots were used to analyse the intermolecular bonding characteristics. Cellulose was modelled with a cellobiose unit (dimer of glu...
V Ponnuchamy, A Sandak, J Sandak, R Herrera Diaz
Development of procedures for sampling, testing, and classification to determine the biological durability of wood and wood products
2020 - IRG/WP 20-20676
This paper informs about a research project, which deals with several shortcomings and a lack of clarity within EN 350:2016. The project started in January 2020, will run for 3 years, and is operated by the Institute of Wood Technology Dresden (IHD) and the University of Goettingen (UGOE).
Determination and classification of durability of wood and wood products against wood-destroying organisms ...
W Scheiding, K Jacobs, S Bollmus, C Brischke
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
Performance of resin-treated solid wood and laminated veneer lumber (LVL) under marine conditions
2021 - IRG/WP 21-10973
Wood is a traditional building material in the marine environment, where it is exposed to extremely harsh conditions. Most of the indigenous softwood and hardwood species in Europe are not durable against attack by marine organisms. Recently, wood modification has been considered as an alternative to protect non-durable wood species under use class (UC) 5 (EN 335, 2013) conditions. The present stu...
L Emmerich, C Brischke, S Bicke, H Militz
Experience Experience from over 20 years of field trials of resin treated wood – Marine borer resistance of MMF and DMDHEU modified wood
2021 - IRG/WP 21-10976
In 1999 a field test of Scots pine treated with MMF (Methylated Melamine Formaldehyde) resin and acetylated Scots pine post treated with MMF resin was started. Six years later a commissioned full NWPC test for BASF of Belmadur® (DMDHEU resin treated wood) was started at the same site.
The testing, according to European Standard EN 275, was done in a bay by Kristineberg Marine Research Station o...
M Westin, P Larsson Brelid, A O Rapp, J Habicht
Influence of weathering on surface roughness of thermally modified wood
2021 - IRG/WP 21-40915
Thermally modified wood is exposed to weathering similarly as other wood-based building materials. It has been reported that if thermally modified wood is exposed to weathering, its moisture performance might decrease fairly fast. The aim of this study was to determine whether this phenomenon is associated with crack formations or roughness. Norway spruce, thermally modified spruce, wax-treated th...
E Kerzic, B Lesar, M Humar
Service trial of different materials exposed in jetties at Öresund. Progress report No. 5
2022 - IRG/WP 22-30764
This report contains results of the fifth inspection on the performance of different decking materials – preservative-treated wood, modified wood, natural durable wood, re-cycled plastics and wood-plastic composites (WPCs) - available on the market and exposed since 2013 (some since 2014 and 2016) by the City of Malmö in two jetties near the Øresund Bridge, south of central Malmö in Sweden. T...
J Jermer
Durability against fungal decay of sorbitol and citric acid (SorCA) modified wood
2022 - IRG/WP 22-40928
Most European-grown wood species are susceptible to biological degradation, specifically, they suffer from a poor resistance against wood-destroying fungi. Therefore, prior to outdoor exposure, wood has to be treated either by applying a protective coating on its surface or by full-volume impregnation with antifungal chemicals. However, due to environmental and health concerns, the most frequently...
K Kurkowiak, L Emmerich, H Militz
Optimized composition of alkyd emulsion with nanoparticles of iron oxide for enhancing protection of thermally modified wood
2022 - IRG/WP 22-40940
Thermal treatment is acknowledged as an environmentally friendly method to improve durability of wood and some of its properties, such as biological resistance, dimensional stability, reduced hygroscopy. Despite these improvements, when used outdoors, also thermally treated wood is subjected to the action of environmental factors, like solar radiation, moisture, precipitations, temperature, etc., ...
E Sansonetti, D Cīrule, I Andersone, B Andersons, E Kuka
The Resistance of Some Commercially Thermally Modified American Hardwoods to Termites and Fungi
2022 - IRG/WP 22-40944
Thermally Modified Wood (TMW) is now being produced in the United States but there are few data on the durability of these materials. In this study, commercially-produced thermally modified yellow poplar (Liriodendron tulipifera), red maple (Acer rubrum), and white ash (Fraxinus americana) were evaluated for fungal and termite resistance. The resistance of the three TMW species against Gloeophyllu...
B Cortes, B Bond, A Taylor, J Lloyd