Your search resulted in 75 documents. Displaying 25 entries per page.
Effects of a formaldehyde and sulphur dioxide treatment on decay and mechanical properties of aspen waferboard
1983 - IRG/WP 3242
Aspen wafers were sequentially treated under vacuum with formaldehyde and sulfur dioxide gas and pressed into waferboard bonded with powdered phenol formaldehyde resin. Decay resistance and strength properties were determined before and after simulated weathering. The water resistance of the phenol bonding system was lost in board made from the gas-treated wafers. This white rot fungus Coriolus ve...
E L Schmidt
The first two years of an area wide management program for the Formosan subterranean termite in the French Quarter, New Orleans, Louisiana
2000 - IRG/WP 00-10357
The Formosan subterranean termite, Coptotermes formosanus, is a serious pest in several parts of the world and is the most destructive insect in Louisiana. The density of the Formosan subterranean termite in the French Quarter, New Orleans, Louisiana, USA is very high. A large area pilot test for area wide management of this insect was begun in 1998 in the French Quarter to reduce densities of ter...
D R Ring, A L Morgan, W D Woodson, A R Lax, X P Hu, E D Freytag, L Mao
Bending creep test of plywoods under long term exposure to fungal attack
1981 - IRG/WP 2163
Bending creep test and decay test were coupled in order to evaluate the durability of structural plywoods and preservative efficacy. Experimental blocks, 5.0 x 1.2 cm² section x 35.0 cm length, were impregnated with distilled water and inoculated with mycelial fragments of test fungus. Polyethylene bags stretched with metal frame were used as decay chambers. The chambers containing inoculated blo...
M Takahashi
Durability of surface preserved wood particle boards submitted to atmospherical influence
1995 - IRG/WP 95-40039
The worldwide problem of the continuously growing deficit of high quality natural wood material has caused the attempts of many research workers to find effective composites such as wood particle boards (WPBs) for replacing the massive wood for constructive purposes, depending on where the boards are exploited - in the open or under a shed, they are submitted to various climatic factors such as he...
L Valcheva
Treatment of wood with formaldehyde. Acid catalysis of the reaction between formaldehyde and wood
1980 - IRG/WP 3146
Formaldehyde reacts with the free OH-groups in wood forming cross-linking bonds. The reaction can be brought about without any catalyst but in that case the activation energy is very high and high temperatures and long reaction times are needed. Normally, the reaction is catalysed by different acids. Acid catalysts, however, tend to degrade the cellulose and the wood matrix causing reduction in th...
T Vihavainen, K Piispanen, P Mansikkamäki
Microscopical analysis of formaldehyde-acid modified wood
1981 - IRG/WP 3182
Cross-linking of wood with gaseous formaldehyde improves its hygroscopic and dimensional behaviour, and its resistance against micro-organisms. However, formaldehyde cross-linking reactions take place only in the presence of an acid catalyst, which results in losses in mechanical By optimization of a formaldehyde-sulfur dioxide vapour phase process the reaction conditions were established to limit...
M Stevens, N Parameswaran
Remedial treatments of glulam = diffusion of active ingredients through glue lines from solid wood diffusable preservatives
1996 - IRG/WP 96-30117
Diffusable preservatives are very suitable for use in remedial treatments of laminated beams in which too high moisture content involves the development of wood destroying fungi. The diffusion of active ingredients (boric acid, disodium octoborate, bifluoride) is well observed in solid wood but in a composite wood, the glue lines may appear not only as a barrier for the diffusion but also, may be ...
D Dirol, S Mouras
Effect of alkaline phenolic resin adhesive on the stability of preservatives incorporated into the glue-line of plywood
1991 - IRG/WP 3650
Stability of preservatives was determined by gaschromatographic analysis when they were applied to glue-line treatment of plywoods. Among organophosphorous insecticides, emulsified forms of chlorpyrifos, dichlofention and diazinon were more stable than others. Fenitrothion, pyridafenthion and phoxim were not practically acceptable as emulsifieable forms due to the relatively low recovery rates aft...
S Fushiki, Y Katuzawa
Studies on the resistance of DMDHEU treated wood against white-rot and brown-rot fungi
2005 - IRG/WP 05-10566
Beech wood (Fagus sylvatica) modified with the textile finishing agent 1,3 dimethylol-4,5-dihydroxyethylen urea (DMDHEU) has shown to improve durability against the white-rot fungus Trametes versicolor. In a mini-block test, the weight loss over eight weeks of incubation decreased with increasing weight percent gain (WPG) of DMDHEU. At 25% WPG, no significant weight loss was observed, while untrea...
P Verma, C Mai, A Krause, H Militz
Biological resistance of wood treated with waterbased resins and drying oils in a mini-block test
1998 - IRG/WP 98-40107
In recent years it was found that the resistance of wood against fungal degradation could be increased by impregnation with an etherificated melamine formaldehyde resin. Using this resin as a reference, a waterbased fatty acid modificated alkyd-resin and two drying-oils were assessed for their biological performance in a mini-block laboratory test. Although drying-oils, like linseed-oil, are often...
M Sailer, A O Rapp, R-D Peek
Test methods for wood preservatives against Lyctus: (1) Testing of treated veneer. (2) Testing of glue-line treated plywood. (Laboratory methods)
1977 - IRG/WP 293
Powder-post beetles destroy large quantities of veneer and plywood. Two test procedures are described which can be used to support application-oriented research into veneer and plywood preservatives. These procedures simulate practical conditions on a laboratory scale. Their characteristic feature is that wood species of special susceptibility are used for the tests; the susceptibility of the spec...
S Cymorek
A study of poplar LVL durability improvement:
1999 - IRG/WP 99-40148
The aim of this study was to optimise the durability of LVL panels by adding boron during the gluing process. Poplar veneers (2,6 mm thickness ) were selected by ISORY a French company . Two types of glue were tested : Phenol resorcine and Melamine Urea Formaldehyde. Each of them was mixed with various concentrations of borax (for the first one) and Boric acid(for the second one). Mechanical prope...
B Charrier, V Bridaux, N Fauroux, F Charrier
Properties-enhanced albizzia particleboards by incorporating fungicide and insecticide in the glue
1994 - IRG/WP 94-30060
Preservative-treated particleboards were prepared by using tropical fast-growing albizzia and adding fungicides and insecticides to the adhesive-glue. the physical and biological properties of these boards were evaluated. No significant reduction in bending or internal-bond strength due to incorporation of the chemicals was detected. Treated particleboards effectively resisted attack by Coptoterme...
B Subiyanto, S Yusuf, Y Imamura, S Fushiki, T Saito, T Katuzawa
Preservation of wood-based panels against fungi and insects and and testing its efficiency
1976 - IRG/WP 270
Wood-based panel products which are made of susceptible wood species may be destroyed by fungi under wet conditions and by termites. The glues do not provide sufficient protection unless very high concentrations are applied. Particle boards and fibre boards are not susceptible to beetle infestation, although some species may attack plywood. Various types of preservatives provide sufficient protect...
G Becker, M Gersonde
The efficacy of preservatives into the glue-line of plywood
1993 - IRG/WP 93-30002
This research is anti-termite/decay preservatives mixed with resin to produce the plywood. Thereafter, anti-decay/termite plywood were produced by the ordinary methods. To produce suitable plywood in the utilization and certified performance, the preservatives should be 0.3 to 0.4 kg/m³ of Chlorpyrifos; 0.88 and 1.10 kg/m³ of mix preservatives of Chlorpyrifos + IF-1000. Laboratories decay test (...
S Fushiki, T Saito, Y Katuzawa, Y Imamura, S Yusuf, B Subiyanto
Glue laminated poles - Progress report after 12 years' testing
1992 - IRG/WP 92-3685
In 1979 a number of glued laminated poles treated with CCA and creosote were placed in a greenhouse at Uppsala, at the Simlångsdalen test field in southern Sweden and under a power line just south of the Arctic circle in order to study their resistance against biological degradation. The tests have shown that the comparatively best performance will be obtained if each laminate is first treated wi...
J Jermer, Ö Bergman
In situ testing the influence of melamine resins on the enzymatic activity of basidiomycetes
1999 - IRG/WP 99-30194
Waterbased methanol etherificated melamine formaldehyde resins have the potential to increase the resistance of impregnated wood against wood destroying fungi. The mechanism of the increased wood durability is not clear yet. In the present paper the possible interference of melamine resins with wood degrading enzymes of Coniophora puteana and Trametes versicolor was investigated as a possible cont...
D Lukowsky, F Büschelberger, O Schmidt
Dimensational stabilisation of wood
1981 - IRG/WP 3171
A review is given of the studies on the dimensional stabilisation of wood which have been carried out in the laboratory 5.14 "Wood Technology" since 1967. All stabilisation methods known have first been compiled from the available literature. Practical studies were then started. Wood was treated with monomers (styrene, methyl metacrylate, isocyanate), formaldehyde, tannin and sugar. Despite a sati...
A Burmester
Future insecticidal treatments for wood products
1980 - IRG/WP 3140
Protective measures involving chemical treatment of wood use only a narrow range of toxic materials which are divisible into two groups, (i) those that are water-soluble, (ii) those that are soluble only in organic solvents. It is generally true to say that, as far as protection against insects is concerned, the former are stomach poisons while the latter are largely (though not exclusively) conta...
D J Cross
Feeding stimulants to enhance bait acceptance by Formosan termites
1994 - IRG/WP 94-10055
Four nitrogenous compounds were found to increase feeding by Coptotermes formosanus Shiraki in the laboratory. Cardboard disks dipped in urea solutions were consumed significantly more than untreated cardboard disks. Cardboard dipped in 8% urea showed a significant change in weight due to termite feeding over other urea treated cardboards. Examination of 15 amino acids in no choice feeding tests i...
G Henderson, M Kirby, J Chen
Effect of aqueous polymer treatments on wood properties. Part 1: Treatability and dimensional stability
1990 - IRG/WP 3610
Partially air-dried sapwood of sweetgum (Liquidambar styraciflua) and southern pine (Pinus spp.) was treated with either aqueous polyacrylate or aqueous dimethyloldihydroxyethyleneurea (DMDHEU) solutions. Tests for dimensional stability were conducted on matched treated and untreated pieces. Measurement of the antishrink efficiency indicated that DMDHEU was a better stabilizer than the polyacrylat...
Z Ashaari, H M Barnes, R C Vasishth, D D Nicholas, D E Lyon
Glue-line additives for protecting plywood. A review
1978 - IRG/WP 2102
The conclusions of this review are: 1) Insecticidal glue-line additives can be used satisfactorily to protect plywood against insect attack. 2) It is uncertain, in spite of some claims, wether fungicidal glue-line additives can be similarly used to protect plywood against fungi under damp conditiones. There is a need for further work to validate the mycological tests that may be used to investigat...
R Cockcroft
Selecting fumigants for treatment of internal decay in wood
1986 - IRG/WP 3370
A number of potential fumigants were screened with respect to their toxicity to decay fungi, (Poria carbonica, and Lentinus lepideus) and their sorption characteristics on Douglas Fir (Pseudotsuga menziesii Mirb. Franco) wood. Wafers of infected wood were exposed to different fumigant concentrations for various times then cultured to determine viability. The lethal concentration X time (ct) factor...
P A Cooper
Soft rot - Soil burial - Tests. Influence of the addition of nitrogen compounds to the soil on wood decay by soft rot
1972 - IRG/WP 213
The decay of wood specimens buried in soil is influenced by various factors. Decisive are the water content, the content of organic substances, the pH-value, the content of mineral nutritive salts, nitrogen content, etc. of the soil. These tests were carried out in order to investigate if the decay of wood in the soil will be influenced by additions of various nitrogen-compounds in different conce...
O Wälchli
Bifenthrin recovery from glue-line-treated plywood
2007 - IRG/WP 07-20355
Plywood and laminated veneer lumber (LVL) can be protected from termite damage by addition of bifenthrin to the adhesive used in product manufacture. However, conditions associated with this manufacturing process may lead to deterioration or immobilisation of the active ingredient. In order to determine compliance with treatment specifications, it is important that the concentration of a preservat...
J Norton, L Stephens