Your search resulted in 269 documents. Displaying 25 entries per page.
Biological degradation resistance of wood acetylated with thioacetic acid
1983 - IRG/WP 3223
Chemically, modification of wood is being considered as an alternative to conventional preservation by toxic chemicals. Acetylated wood has been reported to be quite resistant to most biodegrading organisms at weight percent gains (WPG) around 15-19. The conventional acetylation techniques with acethic anhyrdride result in generation of acetic acid. However, acetylation with thioacetic acid overco...
S Kumar, S C Agarwal
Three years of field tests with "Lignomer" stakes in ground contact
1981 - IRG/WP 3166
The "Lignomer" (Wood Polymer Composite) is a material obtained during the polymerisation of various monomers or its mixtures in wood. As laboratory tests have shown, this material is characterized by a high resistance against biological deteriorating agents. The laboratory investigations on the durability of various materials against biological deterioration are in many instances extended by field...
K Lutomski
A new preservative - A double-edged sword
1990 - IRG/WP 3573
Increasing environmental pressures on the use of pesticides throughout the world will impact more on the use of all wood preservatives. In particular the use of traditional wood preservatives and methods of application are under close scrutiny. The industry is responding to the challenge of developing alternative products and systems but faces great problems due to the excellent performance and sa...
M Connell, J A Cornfield, G R Williams
Pollution in wood preservation - Aspects and problems
1973 - IRG/WP 55
In the field of wood preservation too, pollution problems have to be considered. They originate with the wood preservatives used. The extent of pollution differs widely with the type of preservative and the treatment process used. Per unit of impregnated timber, pollution will be lower if treatment is performed in treating plants than in distributed places. It will be highest for the old type Bouc...
H Willeitner
Influence of the decay of spruce chips by the selected fungi on their chemical structure and the pulp properties
2004 - IRG/WP 04-10510
The paper focuses on changes in the weight and in the molecular structure of spruce chips submitted to long-term storing as well as to medium- and long-term model rotting degradation caused by some chosen fungi identified at storing processes on the pile. For the model decay of chips under laboratory conditions during 3 or 6 weeks the white-rot fungi: Phanerochaete chrysosporium, Heterobasidion an...
R Solár, L Reinprecht, A Geffert, F Kacík
Decomposition of biocides in aqueous media cases of MTC and TCMTB
1993 - IRG/WP 93-50001-26
Our laboratory is interested in the fate of modern biocide molecules in the environment. Here we present recent work which has been done on the fate of two compounds with fungicidal and bactericidal properties: methylenedithiocyanate (MTC: NCS - CH2 - SCN) and thiocyanomethylthiobenzothiazol (TCMTB). We have studied separately the influence of pH, temperature and ultraviolet irradiation in aqueous...
R Perraud, M Papazian
Chemical and biological investigations of double-vacuum treated windows after 7½ years in service
1985 - IRG/WP 3339
Earlier investigations of double-vacuum treated windows after five years in service have shown that tributyltin oxide (TBTO) degrades to di- and monobutyltin compounds and that the resistance of the wood against decay decreases. An investigation 2.5 years later of the same windows shows that the degradation of TBTO proceeds fast. After 7.5 years in service only 15-35% of the remaining organotin co...
M-L Edlund, J Jermer, B Henningsson, W Hintze
Multiple-Phase Pressure (MPP) Process: One-stage CCA treatment and accelerated fixation process. 4. MPP compared with other processes for achieving acceptable treatment of radiata pine heartwood
1998 - IRG/WP 98-40115
Although radiata pine sapwood is very amenable to preservative treatment, it is often difficult to achieve the required standard for heartwood treatment.
A preliminary investigation showed that to achieve the NZ Timber Preservation Council minimum penetration requirements for radiata pine heartwood using the Multiple-Phase Pressure (MPP) Process, a hydraulic pressure of at least 1250 kPa for 20 m...
K Nasheri, J A Drysdale, G Durbin, M E Hedley
Chemical analysis of wood waste - The problem of sampling
1999 - IRG/WP 99-20168
A quantitative analysis of the content of active substances in wood is often demanded in quality control after processing and for the proper waste management. As a measure for quality control, analysis has the advantage that the type of preservative is known and assumptions can be made about its distribution in the treated wood.W aste wood may have been treated by a wide range of organic and inorg...
A Peylo, R-D Peek
Screening of the technical performance and aquatic toxicity of N-methylolacrylamide treated wood
2000 - IRG/WP 00-40166
In the course of the last decades chemical modification of wood species, with a limited natural durability, has been subjected to intensive research. As a possible alternative and supplementary treatment of non-durable wood in a range of applications it remains one of the major topics in the wood preservation world. Different modification systems have been scaled-up and are now in an industrialisi...
V Rijckaert, S De Geyter, J Van Acker, M Stevens
Micromorphological and chemical changes of archaeological woods from wrecked ship's timbers
1987 - IRG/WP 4136
Micromorphological and chemical alterations of sea-waterlogged woods obtained from the ship-wrecked materials which had been submerged in Yellow Sea for over 700 years were investigated. The woods were deteriorated in varying degrees by marine organisms depending on species and parts of the woods. Under the light and scanning electron microscope the morphological characteristics of deteriorated wo...
Y S Kim
Wood protecting chemicals for the 21st century
1993 - IRG/WP 93-30018
After assessing the past research with protection chemicals, this paper proposes future avenues for research and development in wood protection. Three scenarios are put forward for consideration. First, more is not better and future systems will emphasize combination formulations which enhance properties while providing biological efficacy. Second, current systems, especially those based on copper...
H M Barnes
Effect of fungal degradation on the chemical composition of acetylated beech wood
2003 - IRG/WP 03-40267
This study investigated the impact of fungal attack on the chemical composition of acetylated wood. Beech wood acetylated to different degrees was exposed to decay by the white-rot fungus Trametes versicolor under solid-state fermentation conditions. Laboratory soil-bed assays were also conducted to study the degradation of acetylated wood by soft rot fungi and other soil-inhabiting microorganisms...
H Militz, Dong-won Son, L Gómez-Hernández, R Sierra-Alvarez
A 53-year old field trial to evaluate the performance of a range of chemical treatments on eucalypt poles
1989 - IRG/WP 3526
Hardwood pole stubs of Eucalyptus maculata, Eucalyptus pilularis, Eucalyptus saligna and Eucalyptus paniculata were examined for termite attack and fungal decay after 53 years in ground contact. The trial compared eight different chemical treatments with untreated pole stubs of the four species investigated. Untreated Eucalyptus paniculata, a Class I durability species, performed particularly well...
R S Johnstone, R A Eaton
Shorter-term biological control of wood decay in pre-seasoning pine roundwood as an alternative to chemical methods
1992 - IRG/WP 92-1555
Previous studies on the long-term control of decay in creosoted transmission poles, using Trichoderma and other antagonistic moulds, have met with limited success. However, it is possible biological control is more suited to control of decay on shorter time scales. An earlier study, focusing on pre-seasoning treatment of transmission poles showed that favourable porosity increases could be brought...
M W Schoeman, D J Dickinson
FAROX, a novel insect growth regulator for use against wood-boring insects
1995 - IRG/WP 95-30080
The active ingredient in FAROX - fenoxycarb - is a novel insect growth regulator for preventive use against wood-boring insects (Hylotrupes, Anobium and Lyctus). FAROX has the same biological effect as a natural insect growth factor produced by the insect itself. FAROX is tailor-made for insect control; it attacks at the points where the insect should normally be changing its form and blocks these...
A R Valcke
Development of a commercial-scale CCA chemical sludge recycling system
1993 - IRG/WP 93-50001-19
The occurrence of fixation reactions in Copper Chromium Arsenate (CCA) treatment solutions is increased where the treatment of unseasoned and partially seasoned timbers in hot climates occurs. The by-products of the fixation reactions are predominantly insoluble chromium arsenate compounds, commonly referred to as CCA sludge. Historically, this material has been disposed of into toxic waste landfi...
A J B Butler
CCA removal from treated wood by chemical, mechanical and microbial processing
1998 - IRG/WP 98-50101-26
Most preservative-treated wood produced and consumed in the U.S. is treated with toxic inorganic compounds containing copper, chromium, and arsenic. Because chromated copper arsenate (CCA) is fixed to the wood, treated wood has not been considered toxic or hazardous and is currently landfilled. Increasing public concern about environmental contamination from treated wood combined with increasing q...
C A Clausen, R L Smith
The chemical wood preservation in the former GDR - an overview
1995 - IRG/WP 95-50057
For the disposal of chemically treated wood waste and for the remedial treatment of contaminated soils in facility yards a profound knowledge is required concerning the kind of preservatives used and the degree of pollution. In order to record the production of wood preservatives and the location of impregnation plants in the former GDR, documents of the Office for Standardisation Measuring Affair...
E Melcher, R-D Peek
The potential of high pressure pulsation processes to treat white spruce lumber with water-borne preservatives
1988 - IRG/WP 3471
Laboratory work using end sealed 4x8x46 cm³ white spruce samples has been done to explore the suitability of three variants of a 2.1 MPa pulsation process for the impregnation of white spruce with CCA. The results showed that the process improved significantly the penetration of the preservatives and reduced significantly cell collapse, when compared with the results of treatment using a 2.1 MPa ...
J P Hösli, J N R Ruddick
Chromated copper arsenate preservative treatment of hardwoods. Part 1: CCA fixation performance of seven North american hardwoods
1997 - IRG/WP 97-30131
There has been an increased interest in utilisation of hardwoods from eastern North America for exterior applications which require protection with preservatives such as CCA. We have examined CCA fixation at two selected temperatures of seven common North American species: red maple (Acer rubrum L.,), white birch (Betula papyrifera ), yellow poplar (Liriodendron tulipifera L.), trembling aspen (Po...
T Stevanovic-Janezic, P A Cooper, Y T Ung
Resistance of pine and spruce heartwood against decay - The effect of wood chemical composition and coating with water-borne wood oil product
2006 - IRG/WP 06-10597
Natural durability of wood has been widely studied, but the combination of the natural durability and different treatments has not been the focus of many studies. The durability of wooden products is mainly based on the water permeability and the resistance against organisms. In this study, the water absorption and decay resistance of sapwood and heartwood of Scots pine and Norway spruce were exam...
H Viitanen, S Metsä-Kortelainen, T Laakso
Improvement of Grevillea robusta durability using heat treatment
2006 - IRG/WP 06-40333
Heat treatment of Grevillea robusta was carried-out under inert conditions to improve its durability. Resistance of heat treated samples was evaluated by malt agar block tests after three months of exposure to several wood rotting fungi. Results showed that the fungal durability was greatly improved after treatment. There was a good correlation between fungal resistance and mass loss which is a fa...
F Mburu, S Dumarçay, F Huber, M Petrissans, P Gérardin
Performance evaluation of Borax: Boric Acid treated Green bamboo through new VAC-FRI and conventional processes
2006 - IRG/WP 06-40327
Amongst giant arborescent grass bamboo is the only versatile member containing lignocellulosic materials like wood. Therefore it offers almost parallel uses where wood is traditionally an established material. The wood scarcity, environmental role of our natural forests, longer rotation cycle of plantation species, ban in felling, the ever growing utilization demands of wood to the tune of 3.2 mil...
S Tripathi, S N Nautiyal
Chemical reactions involved in furfurylation of solid wood - An investigation by ATR-IR spectroscopy
2006 - IRG/WP 06-40347
Wood modification with furfuryl alcohol (FA) has gained renewed interest during the last five to ten years because of advances in process technology and because of increased focus on the environmental hazards of traditional wood impregnation. The reaction mechanisms involved in the furfurylation process are not yet understood in detail. In the work presented here, the chemical reactions and their ...
T Mark Venås, L Garbrecht Thygesen, S Barsberg