Your search resulted in 187 documents. Displaying 25 entries per page.
Lignin blocking effects on weathering process of wood plastic composites
2010 - IRG/WP 10-40529
The weathering of wood–plastic composites (WPC) causes discoloration which affects their aesthetic aspects. It has been proved that these discolorations are due to lignin degradation. Effects of blocking the susceptible structure of lignin assessed by chemical treatment such as acetylation and methylation are reported in this study. Surface chemical change of wood plastic composite (WPC) formula...
P Darabi, A Naghi karimi, S Ahmade Mirshokraie, M-F Thévenon
Effects of global climate change on mould growth - Interactions of concern
2010 - IRG/WP 10-50270
An evident change in climate the last decades has been recorded, and combined effects of increased CO2, elevated temperature and altered precipitation regimes have been observed to represent a change to the fundamental drivers within ecosystems. Growth of moulds, both in nature and on man-made constructions and objects, will most likely increase due to changes in the climate. The survival, the rep...
L Ross Gobakken
Chapter 7 - Treatment processes of bamboo
2010 - IRG/WP 07-10635-07
For adequate penetration and retention of preservatives in woody
bamboos at green, dry, solid and sliced conditions different possible
and applied treatment processes have been described along with
their classifications. The treated bamboo can be used as building
materials; the sufficient treatability ensures its long-term best
utilization at ground contact and indoor. All the processes descr...
A K Lahiry
Ambient-temperature borate dip-diffusion treatment of green railroad crossties
2011 - IRG/WP 11-40556
In the USA, borates are increasingly being applied prior to air seasoning and creosote treatment of railroad ties (railway sleepers). Borates are typically applied to green ties by vacuum pressure application at 1 to 10% disodium octaborate tetrahydrate (DOT) concentration or by traditional dip-diffusion treatments at elevated temperatures. Higher temperatures are used to maintain the 30 to 50% so...
Jae-Woo Kim, A M Taylor, C Köse
Effects of microclimate, wood temperature and surface colour on fungal disfigurement on wooden claddings
2012 - IRG/WP 12-20490
Wooden claddings are common in façades in Norway, and Norway spruce (Picea abies) is the most frequently used species. The cladding is a major part of the facade, and it has visual requirements that may define the aesthetic service life. The visual changes that occur during weathering can be colour changes, abrasion or wear, blistering, flaking, and even cracks in the wood or coating, but more of...
L Ross Gobakken, G I Vestøl
Accessibility of Wood Cell Walls to Well-defined Platinum Nanoparticles
2012 - IRG/WP 12-20494
Copper nanoparticles are found in the walls of parenchyma cells in southern pine sapwood treated with a micronised wood preservative, but they are absent from tracheid walls. Hence, we hypothesized that small nanoparticles can penetrate the walls of unlignified parenchyma cells, but are excluded from lignified tracheid walls. This paper tests this hypothesis by treating pine sapwood with an aqueou...
H Matsunaga, Y Kataoka, M Kiguchi, P D Evans
Effects of oil types and treatment temperature on the properties of wood subjected to thermal modification in oil medium
2012 - IRG/WP 12-40574
The effect of the use of oil as a medium of heat transfer during thermal modification of different species of wood has been widely investigated with different results accruing with regards to the various end-use properties of the materials. However very little have been done on the effect of oil types as well as its interaction with treatment temperature on the resultant properties of the material...
L Awoyemi, M M Apetogbor, A A Oteng-Amoako
Influence of heat treatment intensity on the structural integrity of 14 timber species
2012 - IRG/WP 12-40586
Thermally modified timber (TMT) is characterized by improved durability and dimensionally stability, but strength properties, especially the dynamic ones, are compromised at the same time. Because dynamic standard tests require high efforts and time, the high-energy multiple impact (HEMI) –test was developed for the fast and reliable characterisation of the structural integrity of TMT, showing a...
C R Welzbacher, C Brischke, G Maier
Field-testing of Norway Spruce Claddings with Monitoring of Moisture Content, Material Temperature and Microclimate
2012 - IRG/WP 12-20502
The physical function of a cladding is to protect the interior construction. Under normal circumstances the performance requirements can be met for a very long time, meaning that the technical service life of a wooden cladding can be very long. Since the cladding is a major part of the facade, it also has visual requirements that may define the aesthetic service life, and often it is much shorter ...
G I Vestøl, L Ross Gobakken
High-throughput sequencing highlighted contrasted pioneer fungal communities associated to coniferous and deciduous wood preservation assays
2013 - IRG/WP 13-10800
Studying the fungal communities in the wood, in particular during the first events of the colonization, and the factors that underlie the dynamics of fungal species assemblages remain a challenge in ecology, because of the absence of fructification during the pioneer steps of wood degradation. The use of Next-generation DNA sequencing methods, which produce massive volumes of data, provided new pe...
Y Mathieu, A Dassé, I Le Bayon, M Kutnik, L Harvengt, E Gelhaye, M Buée
Use of Acoustic Emission (AE) to detect activity of common European dry-woodboring insects: some practical considerations
2013 - IRG/WP 13-10803
Old house borer (Hylotrupes bajulus), Furniture beetle (Anobium punctatum), and Deathwatch beetle (Xestobium rufovillosum) are common dry-woodboring insects occurring throughout Europe. With the aim to prevent unnecessary use of biocidal products, to protect valuable wooden elements and objects from unwanted influences, and to have a more objective method, SHR has started to study the use of acous...
J G M Creemers
The resistance of high performance acetylated wood to attack by wood-destroying fungi and termites
2013 - IRG/WP 13-40621
The resistance of high acetyl solid timber (Accoya) and medium density fibreboard (Tricoya) to attack by wood-destroying fungi and termites was investigated under both laboratory and field conditions. Laboratory studies were conducted in Japan, New Zealand and USA. Field studies were conducted in Australia, Japan, New Zealand, Thailand and UK. The results of the laboratory and field studies agains...
J Alexander, J Hague, M Roberts, Y Imamura, F Bongers, E Suttie
Changes in mechanical and chemical properties of wood exposed outdoors
2014 - IRG/WP 14-20550
The aim of this study was to investigate differences in certain mechanical and chemical properties of three different wood species (common beach (Fagus sylvatica), Norway spruce (Picea abies), and copper-ethanolamine (CuE) impregnated Norway spruce (Picea abies)) that were exposed in use class 3 (CEN, 2006) for periods between 4 and 30 months. The results show, that changes in the investigated me...
N Thaler, C Brischke, D Žlindra, V Vek, M Humar
The effect of preservative treatment on mechanical strength and structural integrity of wood
2015 - IRG/WP 15-30667
The use of wood for demanding construction applications is increasing in Europe. Wooden constructions are frequently designed of susceptible conifer wood, which is endangered by wood decay fungi in wet applications. Therefore in many cases treating wood with preservatives is unavoidable to ensure the desired service life. However, chemical treatment of wood can result in changes of its mechanical ...
M Humar, D Kržišnik, C Brischke
Mould growth on spruce claddings and the effect of selected influencing factors after 4 years of outdoor testing
2015 - IRG/WP 15-30671
Norway spruce (Picea abies) is the most frequently chosen wood species as claddings in façades in Norway, and is used both coated and uncoated. The visual changes that occur during weathering can be colour changes, abrasion or wear, blistering, flaking, and even cracks in the wood or coating, but more often growth of mould and blue stain fungi is the main challenge. A field test with synchronous monitoring of relative humidity, air temperature, material temperature and wood moisture content in Norway spruce claddings has been performed in southern Norway as part of the ClimateLife project. Visual evaluation of blue stain and mould growth according to EN 927-3 was performed, and evaluation data after 46 months exposure is presented. The objectives were to study the effect of 1) environment, 2) cardinal direction and 3) colour of the coated surface on growth of blue stain and mould fungi and to study the variation in relative humidity, air temperature, wood moisture content and material temperature. After 46 months exposure, the red coating system had generally the lowest mould ratings and the uncoated claddings had the highest. Of the white coloured claddings the ones facing south had lower mould ratings than those facing north, but the opposite were found for red coloured claddings. The relative humidity was higher in front of claddings exposed northwards and in a shaded environment compared to an open environment against south. In an open environment red coloured claddings had the lowest wood moisture content and highest material temperature, and red coloured claddings against south had the highest maximum material temperature.
L Ross Gobakken, G I Vestøl
High-frequency monitoring of mass loss due to brown rot degradation of modified wood
2016 - IRG/WP 16-10862
Fungi growing in liquid culture undergoes three separate phases in which they i) adapt to the new environment, ii) grow unrestrictedly and exponentially, and iii) are inhibited to increase in number/mass due to lack of nutrients etc. Filamentous fungi have been shown to exhibit similar growth phases in a solid food substrate and have been modelled to grow in this way also in solid wood. In modifie...
R Ringman, A Pilgård, K Richter
Susceptibility of wood substrates to Aurebasidium pullulans at different temperatures
2016 - IRG/WP 16-10863
There is an increasing awareness of how the aesthetical performance of wood exposed outdoors changes over time and especially in the first few years after installation. Mould and blue stain fungi are biological agents that contribute to the weather grey colour on a wooden façade, and the blue stain fungi Aureobasidium pullulans is commonly identified as colonizer on coated and uncoated wood expos...
L Ross Gobakken, G Alfredsen
Durability of a willow/plastic composite mat
2016 - IRG/WP 16-20592
Developing uses for wood wastes could enhance utilization of low value renewable materials while creating opportunities for rural development. Small diameter willow stems have little use in China, but they could be combined with high density polyethylene to create wood plastic composite mats for decorative applications. These mats could be used in exterior, above ground exposures, but would still ...
Li Yan, Haiyan Duan, Beizhan Quan, J Cappellazzi, J J Morrell
Distribution and penetration of the tung oil in wood studied by high-resolution magnetic resonance imaging
2016 - IRG/WP 16-20593
Water repellents as environment-friendly treatments are gaining their popularity as non-biocidal solutions for wood protection. One of the most important water repellents for wood besides waxes and organosilicon compounds are drying oils. Tung oil is one of the best performing oil. However, tung oil, similarly as other oils, does not penetrate deeply into wood, due to its high viscosity. In order...
M Žlahtič, U Mikac, I Serša, M Merela, M Humar
Fabrication and characterization of MicroPCMs filled wood-plastic composites: Effects of polyethylene glycol on melamine–formaldehyde shell material
2016 - IRG/WP 16-40728
Microencapsulated phase change materials (MicroPCMs) containing dodecanol were fabricated using melamine-formaldehyde (MF) or polyethylene glycol 200 modified melamine-formaldehyde (PMF) resin as the shell materials by in situ polymerization. Wood flour/high-density polyethylene (WF/HDPE) composites with MF shell MicroPCMs (MF-MicroPCMs) or PMF shell MicroPCMs (PMF-MicroPCMs) were prepared, respec...
Xi Guo, Jinzhen Cao
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
Development of Wood Modification – High melting point wax and hot oil treatments
2016 - IRG/WP 16-40768
This study covers an introduction to the projects where new facilities were created for developing wood modification. In this new research environment it is possible to treat wood with versatile equipment. First modifications with this equipment are going to be done in high temperature and pressure using high melting point waxes and hot oils.
Earlier studies, tests and commercial products show...
H Turunen, L Linkosalmi, J Peura, O Paajanen
Effects of climatic factors and material properties on mould growth on untreated wooden claddings
2017 - IRG/WP 17-10884
Mould growth is an important contributor to colour change of untreated wood exposed outdoors. Predicting the development of mould growth is therefore important to ensure successful use of untreated wood as a façade material. More knowledge about the factors affecting mould growth on outdoor exposed wood is required to give better predictions. In this study, climatic factors and material propertie...
S Karlsen Lie, G I Vestøl, O Høibø, L Ross Gobakken
Moisture behaviour and biological durability of high performance flax fibre reinforced composites
2017 - IRG/WP 17-40803
For natural fibre composites in structural and load bearing applications long reinforcing fibres are required. Therefore, much research is performed on flax fibre reinforced composites to optimize them for high performance use. In most cases such research focuses on the mechanical properties, yet the assessment of moisture behaviour, dimensional stability and biological durability is an important ...
N Defoirdt, J Van den Bulcke, F Bensadoun, J Ivens, I Verpoest, J Van Acker
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