Your search resulted in 179 documents. Displaying 25 entries per page.
Photo-discoloration and Degradation of Wood and its Stabilisation by Modification with Benzoyl Chloride
2004 - IRG/WP 04-40274
Photo degradation of Pinus roxburghii (chir pine) and Hevea brasiliensis (rubber wood) was studied under artificial accelerated weathering conditions in a Xenon test chamber. The irradiated samples were analyzed for color changes and chemical changes. Analysis of colour changes in wood surfaces by UV-Vis. irradiation was carried out using a colour measuring (CIELAB) system and chemical changes ...
K K Pandey
Effect of vegetable compost on leaching of CCA components from treated wood - An Update
1995 - IRG/WP 95-50048
In an earlier study, the effect of compost on CCA-C leaching was compared with leaching losses under different exposure conditions. Small treated cubes (25 mm³) were destructively sampled over a 12 month period and the residual CCA determined for exposure to compost in a compost bin, exposed to natural rain and buried in soil. This study provides a comparison after 3 years of samples exposed to c...
P A Cooper, Y T Ung
Xenon simulation of natural weathering of external joinery preserving - Finishing systems
1992 - IRG/WP 92-2412
Semitransparent wood stains ('lazures') for external joinery have developed by means of product combination towards complete wood finishing systems that are easy to applicate, have a good weathering resistance and low maintenance cost. The search for enhanced formulations and the possibilities to standardize these products or treatment systems are always facing long periods of we...
J Van Acker, M Stevens, M Nys
Resolution from IRG Working Group II Sub-group 4 'Stain in timber in service'
1984 - IRG/WP 2230
Sub-group 4 of IRG Working Group II has completed a series of studies of artificial weathering as an alternative to natural weathering in relation to testing the efficacy of chemicals in preventing blue stain in service. The Sub-group reports that within the limits of the equipments studied and described in its report Document No: IRG/WP/2215 the extent of blue stain varied little as a direct cons...
D J Dickinson
Appearance of PEC-treated poles in service
1985 - IRG/WP 3323
Poles treated with conventional high temperature creosote (HTC) are banned for use in Australia by the major union handling them. Pigment emulsified creosote (PEC) is an acceptable alternative because it provides much dryer and cleaner commodities than does HTC. More than 5000 poles have so far been treated with PEC and many are being installed into service. The brown pigmented PEC 30 B has given ...
H Greaves, C-W Chin, K J McCarthy, J B Watkins
Natural weathering of wood in a sunny climate effects on surface chemistry and paint adhesion
1997 - IRG/WP 97-20109
Radiata pine veneers and blocks were exposed to natural weathering under Australian summer conditions over a period of 30 days. Infrared spectroscopy revealed that there was perceptible surface delignification after 4 hours exposure, substantial surface delignification after 3 days exposure and almost complete surface delignification after 6 days. Viscometry determinations on holocellulose samples...
P D Evans, P D Thay, K J Schmalzl
Improving the weather resistance of glue-laminated jarrah and karri
1994 - IRG/WP 94-40017
Surface modification and dimensional stabilisation significantly increased the dry and wet shear strength of karri and jarrah lap-shear specimens (laminates) bonded with resorcinol formaldehyde. The combination of surface modification (sanding/sodium hydroxide treatment), and furfurylation produced the highest dry and wet shear strengths. Acetylated laminates had the lowest dry bond strength, but ...
J Balfas, P D Evans
Laboratory tests on light organic solvent preservatives for use in Australia. - Part 6: Soft rot resistance of three fully formulated preservatives on different timber substrates
2000 - IRG/WP 00-30245
The above-ground soft rot resistance of substrates treated with three fully formulated light organic solvent preservatives (Cuprivac Green WR, Impresol WR 205 and Vacsol) was studied using a modified vermiculite burial method. The substrates were sapwood of Pinus elliottii and P. radiata and heartwood of Eucalyptus regnans, Pseudotsuga menziesii, Shorea sp. (a lower and a higher density source) an...
G C Johnson, M A Tighe, J D Thornton
Natural exposure weathering tests: Their role in the assessment of wood preservative efficacy
1993 - IRG/WP 93-20006
Previous work has demonstrated the potential and usefulness of natural ageing procedures in e evaluation of wood preservative efficacy. This results from the combination of physico-chemical influences and microbiological interactions with both substrate and wood preservative. In this paper, results are presented for a range of biocide types. Discussions are centred on the value of natural exposure...
G R Williams, J Brown
Durability of Wood Plastic Composites Relative to Natural Weathering and Preservative Treatment With Zinc Borate
2005 - IRG/WP 05-40316
Wood-Plastic Composites (WPCs) used for decking have experienced dramatic increases in North America, averaging 25% growth per annum since 1998. A key factor contributing to this growth has been the successfully communicated message that they are "virtually maintenance free". The common perception being that the wood fiber is completely encapsulated by the thermoplastic resin, minimizing the pot...
M E Mankowski, F M Ascherl, M J Manning
Correlation between changes in colour and chemical composition during photo-degradation of wood surfaces
2005 - IRG/WP 05-40301
Changes in colour of wood (yellowing) during photo degradation or weathering reflect chemical changes in wood. Therefore, the relationship between changes in chemical composition and CIELAB colour parameters is very important to characterize photodegradation of lignocellulosic surfaces. In this study, the changes in chemical composition and yellowing due to photo-degradation was studied by expos...
K K Pandey
Properties of hot oil treated wood and the possible chemical reactions between wood and soybean oil during heat treatment
2005 - IRG/WP 05-40304
Thermal treatment with hot oil as the heating media based on the original idea from oil-heat treatment in Germany was investigated. The treatment was mainly carried out at 200ºC and 220ºC for 2 hours and 4 hours, and the wood species were mainly spruce and fir. This paper focuses on the difference between soybean oil and palm oil and the possible chemical reactions between wood and soybean oil. ...
Jieying Wang, P A Cooper
Effect of angle of exposure on degradation of radiata pine during weathering trials
1988 - IRG/WP 2301
The importance of angle of exposure on the degree of weathering of materials has not been adequately resolved. In conventional tests, specimens are exposed at an angle of 45° facing the equator, but more recently experiments on polymeric materials have suggested that an angle of 0° may be preferable since this angle maximises levels of received ultra-violet radiation. In this paper the degradati...
P D Evans
The influence of copper (II) chemicals on the weathering of treated wood. Part 1: ACQ treatment of wood on its weathering
1994 - IRG/WP 94-30040
Wood weathering can be accelerated by alkylammonium compound (AAC) treatment, and slowed by ammoniacal copper quat (ACQ) treatment. This study aims at investigating the influence of ACQ treatment of wood, especially the present of copper (II), on its weathering. ACQ, CCA and DDAC treated microtomed sections of southern yellow pine earlywood were prepared and naturally weathered for five periods, t...
Ruiying Liu, J N R Ruddick, L Jin
Laboratory tests on artificial weathering of Quercus rubra crossties
1986 - IRG/WP 2252
Clear red oak (Quercus rubra) blocks were used to evaluate various types of accelerated aging tests including boil, steaming, and cyclic weathering. It was found that the repeated vacuum and pressure treatment of wood in water, steaming, oven-dry, and freezing appeared to be most effective in reducing the MOE in compression and hardness modules of wood specimens. Red oak crossties which were press...
P Chow, A J Reinschmidt, E J Barenberg, S L Lewis
Fixation of copper-chrome-arsenic treated timber: A comparison of leaching methodologies
1996 - IRG/WP 96-50075
Five packs of kiln dried radiata pine heartwood were treated with copper-chrome-arsenic preservative treated, utilising a modified Bethell treatment schedule. Two methods of determining the level of preservative fixation were compared. These included the diphenylcarbazide method and simulated rainfall testing. The fixation levels were generally higher for tests involving simulated rain leaching. F...
S Walley, P R S Cobham, P Vinden
Resistance of painted wood to mould fungi. Part 3. The effect of weathering, wood substrate and fungicides on mould growth
1998 - IRG/WP 98-10284
The effect of 6 month outdoor weathering on the resistance of acrylate paint systems on different types of pine and spruce sapwood to mould fungi was studied. Dipping into the preservative prior to painting, a primer with and without a fungicide (propiconazole + IPBC 0.50 + 0.2%) and a topcoat with and without a fungicide (propiconazole + IPBC 0.25 + 0.12%) were combinations of the treatments stud...
H Viitanen, P Ahola
Some Experiences with Stake Tests at BAM Test Fields and in the BAM Fungus Cellar
Part 2: Comparison of Static and Dynamic Moduli of Elasticity (MOE)
2005 - IRG/WP 05-20320
In routine in-ground stake tests of wood preservatives at the BAM test field Horstwalde and in the BAM fungus cellar periodical determinations of both static moduli of elasticity (MOE) on the basis of bending tests and dynamic MOE on the basis of the vibration method were performed as a possible method for the assessment of fungal attack. As expected from other publications, the absolute values of...
M Grinda, S Göller
Laboratory and field evaluations of a novel formulation, BAM as an anti-sapstain agent
1991 - IRG/WP 3639
A novel anti-sapstain formulation, BAM, consisting of 2-(thiocyanomethylthio) benzothiazole (TCMTB) and methylene bis thiocyanate (MBT) was evaluated for ist anti-sapstain performance in the laboratory and in the field as well. BAM proved effective in controlling the growth of molds and a sapstaining fungus in the standardized Japan Wood Preserving Association (JWPA) tests. All the test fungi coul...
Y Nomura
A technique for the rapid assessment of wood surface degradation during weathering
1987 - IRG/WP 2281
Radiate pine (Pinus radiata D. Don) sapwood samples taken from four trees were converted into thin strips 100 x 10 x 0.085 (85 µm) mm³, (longitudinal x radial x tangential) in size and exposed in preweighed hatches to the weather inclined at 45° facing equatorially for 10, 20, 40, 60, 80 and 100 days. Significant (P < 0.001) weight losses occurred with time over the exposure period. Differen...
P D Evans, D Abbott, S Thein
Characterization of checks and cracks on the surface of weathered wood
2000 - IRG/WP 00-40153
The surface roughness of unweathered and untreated pine; unweathered copper chromium arsenate type C (CCA) - treated pine; weathered CCA-treated pine; and weathered CCA-plus-water-repellent (WR) - treated pine was evaluated by a stylus tracing method. Surface roughness parameters Ra, Rz, Rmax, Rk, Rpk, and Rvk were measured. Ra, Rpk, and Rvk were the most appropriate parameters for describing modi...
D P Kamdem, Jun Zhang
Durability of exterior natural wood finishes in Brazil
1985 - IRG/WP 3343
Wood finishes systems were evaluated in natural weathering conditions during 5 (five) years, over "Parana-pine" (Araucaria angustifolia). Test samples results show that: - Semitransparent wood preservative stains, based on polimerized linseed oil, provided very good protection to the wood, compared with the one based on alkyd varnish; - Solid color wood preservative stains provided good durability...
D R Macedo
Disodium octaborate tetrahydrate, alone and in conjunction with a selected isolate of Trichoderma viride, reduces decay of fresh felled pine independent of the effect of weathering
1994 - IRG/WP 94-10054
Unpeeled billets of Corsican pine were treated with the following: 5% aqueous disodium octaborate tetrahydrate (DOT) solution; 5% DOT solution with an isolate of Trichoderma viride with a low susceptibility to borate; the Trichoderma viride isolate alone. Half of the billets in each treatment group were also placed in large-diameter plastic pipes to protect the billets from the weather. All three ...
M W Schoeman, D J Dickinson, J F Webber
Rapid loss of lignin at wood surfaces during natural weathering
1992 - IRG/WP 92-2390
Thin veneers of radiata pine (Pinus radiata D. Don) were exposed to natural weathering over a period of 30 days. Incident UV radiation was monitored at the test site. FTIR internal reflectance spectroscopy was used to study the chemical changes taking place at the veneer surface during weathering. Spectra obtained show that after only 3 days exposure there was substantial delignification at veneer...
P D Evans, K J Schmalzl, A J Michell
Permanence of permethrin and bifenthrin in framing timbers subjected to hazard class 3 exposure
2005 - IRG/WP 05-30383
End-sealed Pinus radiata specimens measuring 235 x 90 x 35 mm were treated using a modified Lowry schedule with permethrin or bifenthrin in white spirit to Hazard Class 2 (H2) retentions. After conditioning, the specimens were exposed at 45o on north facing racks near Melbourne (Australia). Samples of the specimens were taken before installation, and after three and six months exposure. Analyses o...
A C Hunt, D G Humphrey, R Wearne, L J Cookson