Your search resulted in 91 documents. Displaying 25 entries per page.
The susceptibility to sludging of sulfate and oxide CCA
1990 - IRG/WP 3599
Radiata pine sapwood was treated separately with a sulphate CCA-C and an oxide CCA in a pilot scale pressure plant using a full cell process. CCA solutions were recovered from the final vacuum phase, placed in plastic tubes, and their susceptibility to sludging determined by examining changes in solution pH, time required for sludge to form and weight and chemical composition of sludge formed. Sul...
B T Mutandadzi, P D Evans
Testing durability of treated wood according to EN 252. Interpretation of data from Nordic test fields
2006 - IRG/WP 06-20341
To evaluate the effectiveness of new wood preservatives intended for treated wood in ground use there is a European standard, EN 252. The test shall run for five years before any formal interpretation of the results can be made.
Due to environmental concerns, the use of wood preservatives based on copper, chromium and arsenic (CCA) has been restricted in recent years. As a consequence of restrict...
M L Edlund, F G Evans, K Henriksen, T Nilsson
Surface and system treatments of wood for outdoor use
2006 - IRG/WP 06-30412
The project “Surface and system treatment of wood for outdoor use” was initiated the summer 2001. The project evaluates environmentally friendly preservatives and water borne coating systems, to find the best protection for timber indented for outdoor use. The wood species selected as test material were pine and spruce. The different treatments were exposed in several outdoor accelerated tests...
B Jacobsen, F G Evans
Preliminary Observations of the Effect of Kerfing on the Surface Checking and Warping of Flat Sawn Southern Pine Decking
2007 - IRG/WP 07-20360
Checking and warping of decking timber are serious defects and methods of reducing their severity are required to ensure that wooden decking can compete with alternative decking materials. Kerfing is effective at reducing the checking and distortion of square cross-section lumber, and the checking of roundwood. In the past it has also been applied to preservative treated decking boards, however, t...
R Ratu, J Weizenegger, P Evans
The Effect of Solar Radiation on the Surface Checking of Wood
2007 - IRG/WP 07-40356
The aim of this research was to investigate whether exposure to solar radiation increases the checking of wood exposed to the weather, and examine the causes and spectral dependency of such an effect. Lodgepole pine samples were exposed outdoors under filters which transmitted selected regions of the solar spectrum while allowing other weathering factors to act on samples. Surface checking in samp...
P Evans, K Urban
Micro-Distribution of Metals in Wood Treated with a Nano-Copper Wood Preservative
2007 - IRG/WP 07-40360
The microdistribution of copper in southern pine treated with a newly-developed nano-copper wood preservative was examined to determine if it differed from that reported for wood treated with conventional copper-based wood preservatives. Field Emission Scanning Electron Microscopy (FE-SEM) in combination with x-ray microanalysis (EDX) revealed the presence of nano-sized copper and iron particles i...
H Matsunaga, M Kiguchi, P Evans
The influence of different creosote process parameters on penetration, retention and bleeding on glulam
2007 - IRG/WP 07-40368
Different process parameters were used to treat Scots Pine glulam beams with creosote. Parameters like pre-heating, pre-pressure time, pressure and pressure time were changed. Most treatments gave a full or almost full penetration of creosote into the sapwood, but the uptake of creosote in the sapwood varies.
All samples, except the one with poor penetration, showed heavily bleeding of creosote ...
F G Evans
Natural durability of different wood species in above ground applications - Weight and MOE loss
2008 - IRG/WP 08-10667
In Norway, exterior wood structures have traditionally, nearly exclusively been made of untreated Norway spruce (Picea abies (L.) Karst) and pressure treated Scots pine (Pinus sylvestris L.). In recent years there has been a tendency that other wood species, like various Norwegian hardwoods or imported species, have been used in exterior above ground applications, often not surface treated. For se...
F G Evans, P-O Flæte, G Alfredsen
Development of a Weatherometer to Accelerate the Surface Checking of Wood
2008 - IRG/WP 08-20388
There is significant interest in developing preservatives that are better at preventing wood from checking. Currently, however, there is no accepted test methodology for accelerating the development of checks in wood samples so information on the effectiveness of treatments at restricting checking can be obtained more quickly. This paper describes the development of a new type of weatherometer (Ac...
R Ratu, P D Evans
Formation and Structure of Metal Azole Complexes
2008 - IRG/WP 08-30469
Divalent copper and zinc complexes with metal:azole ratio 1:2 were readily formed at room temperature with the fungicides tebuconazole and propiconazole. The structure of copper and zinc tebuconazole acetate and zinc cis-propiconazole chloride were examined by X-ray crystallography. In copper tebuconazole acetate, the copper atom lies on a crystallographic inversion centre and is coordinated to tw...
P D Evans, K J Schmalzl, C M Forsyth, G D Fallon, S Schmid, B Bendixen, S Heimdal
The Effects of Solar Radiation on the Fungal Colonization and Color of Weathered Wood
2008 - IRG/WP 08-10676
Solar radiation rapidly depolymerizes lignin at wood surfaces exposed outdoors producing a suite of low molecular weight aromatic compounds within weathered wood. Fungi colonizing weathered wood are able to metabolize these aromatic compounds, and many of them also contain high levels of melanin to protect themselves from the harmful effects of UV radiation. Both of these adaptations suggest that ...
V Hernandez, C Breuil, P D Evans
Improving the Dimensional Stability and Fire Resistance of OSB by Roller-Coating Panels with UV-Curable Finishes
2008 - IRG/WP 08-40434
Oriented strandboard was sanded and roller-coated with UV-cured finishes. The effects of these treatments on the surface roughness, dimensional stability and fire resistance of OSB were assessed. Sanding reduced the average roughness of OSB, but it had a smaller effect on maximum roughness because sanded boards still contained surface voids between some strands. Sanded boards absorbed less than ha...
P D Evans, I Cullis
Wart Morphology can Distinguish White Cypress Pine from the Less Durable Species, Black Cypress Pine
2009 - IRG/WP 09-20406
White cypress pine (Callitris glaucophylla) wood is durable enough to be used outdoors, but occasionally there are reports of its premature failure in ground contact, which may be due to its substitution by the less durable species, black cypress pine (C. endlicheri). It has been difficult to prove this, however, because the woods of both species are very similar in structure and cannot be separat...
R Heady, R Cunningham, P Evans
Use of Confocal Profilometry to Quantify the Weathering of Wood
2009 - IRG/WP 09-20421
The methods that have been used to screen chemicals for their ability to prevent the weathering of wood involve assessing the loss in weight and tensile strength of treated wood veneers or measuring the rate of erosion of exposed and unexposed (masked) wood subjected to weathering. The erosion of wood during natural weathering occurs slowly and long exposure times are required to produce differenc...
Chunling Liu, P Evans
Leaching of the copper component from full scale decking boards during one summer season
2009 - IRG/WP 09-50260
The leaching of copper has been tested in laboratory and in outside exposure for freshly treated pine sapwood samples with three different copper preservatives, Cu HDO, copper quat and copper triazoles. We found in the laboratory leaching test that a fixation with warming to 60 °C (140 °F) for 48 hours without drying and then drying in the laboratory in room temperature gave the lowest leaching of copper. We also found that surface treatments with wood oils reduced the leaching, and that washing of the surface before testing had no effect.
Full scale decking board samples (0.25 m2) were then exposed outdoors for rain. The rain water was collected and analysed for copper. After one summer season (about 600 mm rain) we found that the leaching differ for the three preservatives. All samples with a water borne surface treatment had the lowest leaching, about half the amount of untreated.
F G Evans
Vinyl Benzoate Photostabilizes Wood Whereas Vinyl Cinnamate and Vinyl 4-T-butylbenzoate are Less Effective
2009 - IRG/WP 09-40452
Thin wood veneers were esterified to different weight gains with three different aromatic vinyl esters, vinyl benzoate, vinyl cinnamate and vinyl 4-T-butylbenzoate and the photostability of the modified wood was examined. There was a linear relationship between the level of esterification of wood with vinyl benzoate and the photostability of the modified veneers exposed to natural weathering. Viny...
M Jebrane, G Sèbe, I Cullis P Evans
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
The Use of Micro-Tensile Testing to Assess Weathering Decay and Oxidative Degradation of Wooden Items
2010 - IRG/WP 10-20433
This paper presents a method to study the weathering performance of wooden items and to assess the oxidative degradation of wood via the Fenton reaction. Weathering resistance and photo-stability of wood was tested using pine wood (Pinus sylvestris) veneer strips measuring approximately 60 µm in thickness. The veneer strips were treated using a reactive chemical to impart surface protection. The ...
C Mai, Yanjun Xie, Zefang Xiao, P D Evans, H Militz
Finite Element Modelling of the Checking of Wood Exposed to Accelerated Weathering
2010 - IRG/WP 10-20459
The surface checking that develops when wood is exposed to the weather reduces the visual appeal of treated wood products and can reduce the effectiveness of preservative treatments. There is strong interest in developing solutions to this problem and also a growing realization that such solutions may evolve from a deeper understanding of the mechanisms responsible for surface checking. In this pa...
S G Ribarits, P D Evans
Photostabilization of Wood with Higher Molecular Weight UV Absorbers
2010 - IRG/WP 10-30524
Higher molecular weight UV absorbers were created by reacting the epoxy-functionalized UV absorber 2-hydroxy-4(2,3-epoxypropoxy)-benzophenone (HEPBP) with maleic, phthalic or succinic anhydride. The ability of the UV absorbers to photostabilize wood was then examined. FTIR-spectroscopy confirmed that HEPBP reacted with phthalic anhydride to create a polyester that preserved the UV-absorbing benzop...
P D Evans, M J Chowdhury
Copper nanoparticles in southern pine wood treated with a micronised preservative: Can nanoparticles penetrate the cell walls of tracheids and ray parenchyma?
2010 - IRG/WP 10-30547
This study tests the hypothesis that copper nanoparticles can penetrate the cell walls of southern pine wood treated with a micronised preservative. We examined the nanodistribution of particles in tracheid and ray parenchyma cell walls using state-of-the-art HR (High Resolution)-TEM and HR-STEM (Scanning Transmission Electron Microscope)-EDX. These devices are capable of atomic-scale resolution. ...
H Matsunaga, Y Kataoka, M Kiguchi, P Evans
Preliminary Observations of the Photostabilization of Wood Surfaces with Cerium Oxide Nanoparticles
2010 - IRG/WP 10-40504
Reactive transition metal compounds, wood modification and grafting of UV absorbers have all been used to photostabilize wood. Some of these approaches are promising, but the toxicity of certain reactive transition metal compounds and the cost of wood modification and grafting have restricted their commercial applications. Hence, more cost-effective and environmentally friendly methods of protecti...
Chunling Liu, A Ahniyaz, P Evans
Copper distribution in soil leached from full scale decking boards during one year
2010 - IRG/WP 10-50265
The distribution of copper in the soil under exposed decking boards after one year has been analysed. The decking boards were impregnated with copper HDO, copper quat and copper triazoles. The decking boards were pine sapwood and pressure treated in a full cell process, fixed by heating and then dried. The samples were not surface treated. Each decking sample of five boards (0.25 m2) was placed on...
F G Evans
Natural durability of wood tested in different environments in Northern Europe
2011 - IRG/WP 11-10747
Moisture is often recognised as a key factor regarding the long time performance of wooden products, and one of the main challenges for timber products is to predict accurate service life in use class 3 (not covered above ground) and use class 4 (in soil or fresh water contact). A range of durability classification studies have been performed both in field and laboratory. But for several wood spec...
P O Flæte, G Alfredsen, F G Evans
Copper Nanoparticles in Southern Pine Wood Treated with a Micronised Preservative: Nanodistribution of Copper in the Pit Membrane and Border of an Earlywood Bordered Pit
2011 - IRG/WP 11-30566
Copper nanoparticles can penetrate the cell walls of unlignified parenchyma cells in southern pine wood treated with a micronised wood preservative, but they are excluded from lignified tracheid walls. This paper extends these observations to include the cell wall layers of the bordered pit. Focused ion beam and ion milling were used to make an ultra-thin section of the cell wall layers of an earl...
H Matsunaga, Y Kataoka, M Kiguchi, P Evans