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Effects of methoprene on Coptotermes formosanus (Isoptera: Rhinotermitidae)
1987 - IRG/WP 1322
Methoprene affected differentiation and survival of Coptotermes formosanus Shiraki in laboratory studies. At 5, 9, 13, and 17 weeks, superfluous intercastes and presoldiers were produced when termites were allowed to feed on concentrations of 1,000 and 2,000 ppm methoprene in wood blocks. Colony numbers were significantly reduced after 13 and 17 weeks of exposure to the insect growth regulator. Termites are significantly less of the treated blocks than of the controls and sometimes physically sealed off the treated blocks, which suggests that some concentrations of methoprene may have slight antifeedant properties. Colonies varied in their responses to this chemical.
S C Jones


Some tests on ES - AS 11, a novel anti-sapstain formulation, and its properties
1987 - IRG/WP 3399
The results of some tests with the formulation ES - AS 11 are given. The formulation is an attempt to improve the performance of an anti-sapstain chemical by: 1) increasing its penetrability 2) uniquely combining its active ingredients. Very short times of treatment (dipping not longer than 5 seconds), low concentrations of active ingredients, and lower toxicological and environmental risks may be a promising result.
U Straetmans


Effects of timber surface properties and dipping conditions on uptake of antisapstain actives from two aqueous suspensions, and ultimate effects on efficacy against mould and staining organisms
1995 - IRG/WP 95-30073
Green-off-saw rough sawn Pinus elliottii (slash pine) boards were dipped in aqueous suspensions of two antisapstain formulations, and the resultant surface retentions of active ingredients MTC (methylene bisthiocyanate), CTL (chlorothalonil) or TCMTB (2(thiocyanomethylthio)benzothiazole) were monitored by chemical analysis. Surface retentions increased with suspension concentration and surface roughness, and decreased with initial timber moisture content. Dipping time beyond 20 seconds, timber basic density and earlywood content had little effect. Relatively low surface retentions, produced by dipping smoother boards with higher initial moisture contents, provided lower protection against mould and stain during seasoning than higher retentions. Equations describing the effect of surface retention on efficacy were developed for both formulations, and retentions providing complete protection under the conditions of the test were determined.
M J Kennedy, T L Woods


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. Generally palm oil was slightly better than soybean oil in improving the moisture resistance properties of heat-treated wood. But soybean oil treated wood appeared to have better decay and mould resistance. The mass loss of wood treated in soybean oil at 220ºC for 4 hours was below 20 % after exposure to Gloeophyllum trabeum in a soil block test, so the treated wood can be classified as “Resistant” according to ASTM D 2017 standards. Natural weathering exposure also shows that soybean oil treated wood is more mould resistant than palm oil treated wood. In order to investigate the effects of absorbed oil on the properties of treated wood and the possible reactions between wood and oils, extraction of different vegetable oil treated wood with chloroform and other solvents was carried out. The results suggest that part of the soybean oil could undergo chemical reactions with wood that renders it of low extractability.
Jieying Wang, P A Cooper


Oxine copper (NYTEK® GD) for the control of mould and sapstain on lumber in North America
1989 - IRG/WP 3517
NYTEK® GD is a new, water-based, micro-dispersible formulation of oxine copper registered in the United States and Canada for control of mold and sapstain-causing fungi. NYTEK GD is noncorrosive and of low hazard to applicators and people handling treated lumber, when used according to the label. The product is an effective wood protectant applied as a dip or spray treatment at concentrations of 0.32-0.63% ai (by wt.) on major species of lumber including hem-fir and southern pine. The duration of activity is 4-6 months on artificially inoculated wood incubated in environments that encourage fungal development. Shorter duration control may be observed on Douglas fir. Efficacy is improved by a tank mixture with 2% borate. The unique combination of safety, noncorrosiveness, and efficacy make NYTEK GD a sound alternative to penta-and tetrachlorophenates for wood protection.
D F Myers, J M Fyler, C H Palmer, G D Rosebery


Anti-feedant activity of stilbenic components from bark of Picea glehnii against a subterranean termite, Reticulitermes speratus
2002 - IRG/WP 02-10447
Stilbenic components, one of polyphenolic groups, widely distributed in plant bodies have been known as anti-microbial agents, but not known whether to have anti-termite activities. A stilbene glucoside, isorhapontin, from the bark of Picea glehnii was examined on the anti-feedant activity against a subterranean Reticulitermes speratus. Isorhapontigenin, the aglycone of isorhapontin, induced from it by hydrolysis using ß-glucosidase was also tested for comparison. From the results of choice and no choice feeding tests using paper disks, anti-feedant activity was shown in both the compounds. Isorhapontigenin had a larger anti-feedant activity than isorhapontin.
S Shibutani, M Samejima, S Doi


Influences of the hydro-thermal treatment on physical properties of beech wood (Fagus orientalis)
2005 - IRG/WP 05-40303
Influences of the hydro-thermal treatment on physical properties of beech wood were studied. Wood specimens (2×2×2cm) were treated in two steps. At first step, samples were treated at 160,180 & 200ºC for 4, 5 & 6 hours. At second step, treated samples were cured based on their first step treatment temperatures (160,180 & 200ºC) for 16 hours. The treated samples were soaked in water and oven dried for 24 hours. The soaking-drying cycles were repeated for seven times. Oven dried density (initial and final), swelling (initial and final), water absorption (initial and final) and density loss were analyzed. Results revealed that swelling was decreased due to the hydro-thermal treatment; while the water absorption was increased in wood. And oven dried density was slightly lost due to the treatment. The density loss and increase of water absorption are related to initial pyrolysis of wood which consequences with increase of wood porosity due to the treatment.
B Mohebby, I Sanaei


Evaluation of the effectiveness of defence anti-stain in the control of sapstain in laboratory and field tests
1990 - IRG/WP 3593
The anti-sapstain product Defence Anti-stain (DAS) has been evaluated internationally in laboratory and field tests during the years 1988 and 1989. Results of tests carried out by institutes and by own companies in countries like Indonesia, Ivory Coast, Japan, Portugal, Belgium, The Netherlands and Spain will be presented. In the several tests Defence Anti-stain showed a high fungicidal activity to sapstain and mould fungi on wood. The product is a promising alternative to sodium pentachlorophenoxide from biological and other product characteristics point of view.
G Rustenburg, C J Klaver


Anti-fungal properties of pyrolytic oils derived from softwood bark
2000 - IRG/WP 00-30218
Thermal decomposition of balsam fir and white spruce mixed bark residues at 450°C and under vacuum (< 20 kPa abs.) results in high yields of pyroligneous liquors rich in phenolic content. This vacuum pyrolysis process has been scaled-up to a pyrolysis plant with a feed capacity of 3.5 t/h of softwood bark, which is the largest plant of this type in the world. The pyrolytic aqueous condensates have been tested for their anti-fungal properties. One of the major objectives of this study was to identify which groups of chemical compounds were the most active to inhibit the growth of wood decay fungi. The fractionation of the pyrolytic aqueous phase in four distinct parts was accomplished by a liquid-liquid extraction method. The four fractions were named F1 (ether extractibles), F2 (ethyl acetate extractibles), F3 (neutral compounds) and F4 (phenolic compounds). Petri tests were conducted using two brown rot fungi (P. placenta and G. trabeum) and two white rot fungi (I. lacteus and T. versicolor). The composition of these fractions was analysed by GC/MS. Fraction F1, with concentrations of organic acids, phenols and derivatives (3.0% by weight), benzenediols (3.9% by weight), and a variety of other products (quinones, furans, etc.), was the most promising to inhibit the growth of decay fungi, while fraction F3 showed no inhibitive effect in the Petri dish agar test. C. versicolor was most sensitive to these fractions, while I. lacteus was the least. The addition of CuSO4 to the water soluble organics improved their ability against decay.
D Mourant, Dian-Qing Yang, Xiao Lu, C Roy


Relationships between heat treatment intensity and some conferred properties of different European softwood and hardwood species
2012 - IRG/WP 12-40593
Effect of treatment intensity on conferred properties like elemental composition, durability, anti swelling efficiency (ASE) and equilibrium moisture content (EMC) of different European softwood and hardwood species subjected to mild pyrolysis at 230°C under nitrogen for different durations has been investigated. Independently of the wood species studied, elemental composition is strongly correlated with the mass losses due to thermal degradations which are directly connected to treatment intensity (duration). In all cases, an important increase of the carbon content associated with a decrease of the oxygen content was observed. Heat treated specimens were exposed to several brown rot fungi and the weight losses due to fungal degradation determined after 16 weeks, while effect of wood extractives before and after thermal treatment was investigated on mycelium growth. ASE and EMC were also evaluated. Results indicated important correlations between treatment intensity and all of the wood conferred properties like its elemental composition, durability, ASE or EMC. These results clearly indicated that chemical modifications of wood cell wall polymers are directly responsible for wood decay durability improvement, but also for its improved dimensional stability as well as its reduced capability for water adsorption. All these modifications of wood properties appeared simultaneously and progressively with the increase of treatment intensity depending from treatment duration. At the same time, effect of extractives generated during thermal treatment on Poria placenta growth indicated that these latter ones have no beneficial effect on wood durability.
M Chaouch, S Dumarçay, A Pétrissans, M Pétrissans, P Gérardin


Effects of nano-wollastonite impregnation on fire resistance and dimensional stability of Poplar wood
2012 - IRG/WP 12-40595
The fire-retardant properties of Nano-Wollastonite (NW) in poplar wood (Populus nigra) were determined in this study. Some physical properties such as water absorption, volumetric swelling and Anti-Swelling Efficiency (ASE) were also measured. Specimens were prepared according to the ISO 11925 standard for the fire-retarding properties, and ASTM D4446-2002 standard for the physical properties. Impregnation of wood specimens with nano-wollastonite was carried out using the Ruping Method (empty-cell process) with a concentration of 10%. Three fire-retarding properties were measured; weight loss, ignition point and fire endurance. The results showed that fire-retarding properties increased in the NW-treated specimens. In addition, the NW-impregnated specimens gained higher dimensional stability. However, the water absorption also increased.
A Karimi, A Haghighi Poshtir, H Reza Taghiyari, Y Hamzeh, A Akbar Enayati


A practical method to evaluate the dimensional stability of wood and wood products
1990 - IRG/WP 2342
This paper presents a new simple method to evaluate wood and wood products for their resistance to swelling and to assess wood preservatives for their ability to dimensionally stabilize treated wood exposed to water. Permeable wood of various dimensions and treated with different preserving chemicals have been measured for swelling in the radial and tangential direction during immersion in liquid water. The results indicate that a simple exponential function describing the dimension of the samples during immersion can be used to evaluate both the water-repellency and anti-swelling effectiveness of wood preserving chemicals. The results can be achieved in reasonable time, and the parameters of the function can be determined by a commercial desk-top computer program.
J P Hösli


Physical properties of ß-1,4-Xylanase produced by Postia (=Poria) placenta: Implications for the control of brown rot
1987 - IRG/WP 1318
The degradation of hemicelluloses is an early event in wood decay by brown-rot fungi. An understanding of the physical properties of hemicellulases may suggest target mechanisms for the development of new control agents. Endo-b-1,4-xylanase was partially purified by column chromatography from wood decayed by Postia (= Poria) placenta. The enzyme was extremely resistant to denaturing conditions; no loss of activity was detected after 2 h in 9 M urea or 6 M guanidine-HCl. Boiling the enzyme for 5 min in 2.5% SDS + 0.5% b-mercaptoethanol reduced its activity by 65%, as measured by the production of reducing sugars. The activity of a-D-galactosidase, another enzyme detected in large quantities in the decayed wood, was reduced by 98% under these conditions. Optimum pH and temperature ranges were pH 2-6 and 50-60°C, respectively. The enzyme appears to be a glycoprotein containing 50-60% carbohydrate (w/w); the carbohydrate moiety may protect the enzyme from adverse environmental conditions. The control of brown rot by in situ inactivation of xylanase may not be feasible because of the enzyme&apos;s extreme stability.
J A Micales, F Green III, C A Clausen, T L Highley


Effectiveness of "Gang-Nail" plates in preventing splitting of Eucalyptus poles and Brazilian hardwood sleepers
1984 - IRG/WP 3262
This paper presents the results of some tests carried out with an anti-splitting device, placed on the end surfaces of Eucalyptus spp utility poles and Brazilian hardwood sleepers at the beginning of an air-drying period. The type of device used, a "Gang-Nail" plate, reduces significantly the splits at the end-surface of poles, but reduces only a little the splits occurring in sleepers.
A M F Oliveira, J A C Sodré, O B Neto


Wood furfurylation process and properties of furfurylated wood
2004 - IRG/WP 04-40289
The first processes for “furfurylation” of wood (wood modification with furfuryl alcohol) were developed several decades ago. Furfuryl alcohol is a renewable chemical since it is derived from furfural, which is produced from hydrolysed biomass waste. Over the last decade modernised processes for furfurylation of wood have been developed. These new processes are based on new catalytic systems and process additives. Two main processes for production of furfurylated wood have been developed for WPT (Wood Polymer Technology ASA) by the authors – Kebony&#61652; 100 for high modification levels of hardwoods and VisorWood&#61652; for lower modification levels of pine. Commercial production according to the Kebony process has been running since August 2000, mainly for flooring. A small Kebony production plant is now in operation in Lithuania. A larger Kebony/VisorWood production plant started up in September 2003 in Porsgrunn, Norway. Several new plants operating according to the VisorWood process, each with an annual capacity of 10 000 m³ or more, are under construction. The properties of furfurylated wood depend on the retention of grafted/polymerised furfuryl alcohol (PFA) in the wood. At high modification levels (high retention of PFA) the enhancement of a wide variety of properties are achieved: an exceptional hardness increase, exceptional resistance to microbial decay and insect attack, high resistance to chemical degradation, increase in MOR & MOE, and high dimensional stability. At lower modification levels many property enhancements also occur, however to slightly lower extent. Notable are resistance to microbial decay and insect attack, increase in MOR & MOE, and relatively high dimensional stability.
M Westin, S Lande, M Schneider


Effect of medium-term degradation of beech wood by erosive (Phanerochaete chrysosporium) and lignin-selective (Ceriporiopsis subvermispora) strains of white rot fungi on its selected physical properties
2004 - IRG/WP 04-40292
At the Faculty of Wood Sciences and Technology a fungal delignification of normal and tension beech wood by erosive and lignin-selective strains white-rot fungi has been studied. The pre-treatment of both kind of wood samples was accompanied by partial delignification and apparent changes of their physical properties influencing the polar liquids penetration.
R Solár, S Kurjatko, M Mamonová, J Hudec


Di-sodium fluorophosphate, a new fluorine containing, water-borne wood preservative
1986 - IRG/WP 3373
The physical, chemical properties of Di-sodiumfluorophosphate (Na2PO3F) are compared with those of a trade-mark SF-salt. The opposition of biological activity and toxicological data showed that Di-sodiumfluorophosphate may be a suitable alternative to SF-salts ( based on MgSiF6).
D Seepe, W Metzner


Commercially available anti-sapstain chemicals in New Zealand - An update
1987 - IRG/WP 3416
Six anti-sapstain chemicals or mixtures (NaPCP plus borax, Haipen 5F, Mitrol PQ375, Busan 1009, Protek S, Pinefol 50W) are available as commercial treatments in New Zealand. A further two (Hylite 20F and Isothon-35) have shown potential in field and mill trials and will be available for use. A number of other formulations are under evaluation.
J A Drysdale


Cu, Cr and As distribution in soils adjacent to CCA treated utility poles in Eastern Black Sea Region of Turkey
2004 - IRG/WP 04-50214
In this study, the main objective was to asses the distribution of Cu, Cr, and As in soils adjacent to CCA treated utility poles in Eastern Blacksea Region of Turkey (Trabzon, Rize and Artvin ) and determine the influence of soil composition. Surface (0-5cm), subsurface soil samples (30-40cm) were collected near CCA-treated utility poles and control soil samples away from CCA-treated utility poles were also collected. Water holding capacity, pH, mechanical properties of soil samples were determined for both depth levels. Results showed that Cu, Cr and As concentration in soil samples taken from all three cities in 0-5cm depth was higher than soil samples taken from 30-40cm depth. Cu, Cr and As concentrations were much higher in soil samples taken from city of Rize.
E D Gezer, Ü C Yildiz, A Temiz, S Yildiz, E Dizman


Physical and biological properties of albizzia waferboards modified with cross-linking agents
1995 - IRG/WP 95-40043
Chemically-modified low-density waferboards with cross-linking agents were produced using a fast-growing species of hardwood albizzia (Paraserienthes falcata Becker) as a raw materials and isocyanate resin as a glue adhesive. For the chemical modification, the vapor-phase formalization of the boards and the pad-dry-cure treatment of wafers with cross-linking agents were employed. The vapor-phase formalization was conducted for 5, 10 and 24 hours using tetraoxane as a source of formaldehyde, and the pad-dry-cure treatments with glutaraldehyde and ethyleneurea compound (DMDHEU) were made after impregnation of their 5 and 10% aqueous solutions of each chemical. Sulfur dioxide was used as a catalyst in both treatments. About 70% of antiswelling efficiency (ASE) was gained in all treated boards irrespective of reaction time or solution concentration. All treated boards were very stable to water soaking even in the 2-hour boiling on thickness swelling as well as linear expansion. Laboratory tests with brown-rot and white-rot fungi revealed that decay was completely suppressed in formaldehyde-treated boards, and small losses in weight were counted in other treated boards. All treated boards were also effective in resisting to the attack by the destructive termite Coptotermes formosanus.
S Yusuf, Y Imamura, M Takahashi, K Minato


Effects of various preservative treatments on the mechanical and physical properties of plywood
1993 - IRG/WP 93-40007
The technical properties of plywood are related to both the intrinsic characteristics of its composing wood species and the quality and performance of the glue bond which acts as an interface between veneer sheets. Consequently mechanical and physical testing and glue bond strength analysis offer an appropriate means for studying the effect of preservative treatments on the overall quality of plywood. A range of boards was treated with waterborne and oilborne preservatives. Changes in modulus of elasticity, modulus of rupture and tensile strength were noted as well as variations in physical properties. Analysis of the glue bond strength was done by shear strength testing and determination of the amount of wood failure after different ageing procedures.
J Van Acker, M Stevens


In search of alternative antisapstain chemicals for use in Papua New Guinea
1988 - IRG/WP 3472
The paper presents results of antisapstain field trials from three locations in Papua New Guinea as part of the Research Centre&apos;s programme to find suitable antisapstains to replace the hazardous sodium pentachlorophenate. Effectiveness of seven tested chemicals varied between indigenous pines (Araucaria cunninghamii, Araucaria husteinii) and white coloured hardwoods (Alstonia scholaris, Pterocymbium beccarii) but not between sites. The indigenous pines required lower chemical concentration for same level and period of protection than white coloured hardwoods like amberoi and white cheesewood. Period of protection ranged from four weeks to a maximum of 16 weeks depending on chemical concentration and species of timber. Potential chemicals recommended for use as antisapstain include Celbrite T, Busan 1009, Penacide and Woodguard E.S. and Woodguard E.C.
A Oteng-Amoako


Discussion of diiodomethyl p-tolyl sulfone (Amical® 48) as a fungicide for wood preservatio
1987 - IRG/WP 3425
The effectiveness of diiodomethyl-p-tolyl sulfone (Amical® 48) as a fungicide for preservation of wood is supported by a discussion of results from the literature and current research programs.
J M Stamm, K J Littel, F M H Casati, M B Friedman


Nouvelles techniques de lutte anti-termites à faible impact environnemental
1995 - IRG/WP 95-50040-32
P Martinet


Mould resistance of lignocellulosic material treated with some protective chemicals
1984 - IRG/WP 3294
Effectiveness of preserving lignocellulosic material against moulding by treatement with water solutions of commercial wood preservatives and mixtures of various inorganic salts was investigated and compared with the effectivenes of sodium pentachlorophenoxide and boric acid.
K Lutomski


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