Your search resulted in 27 documents. Displaying 25 entries per page.
Wood preservation by a mixed anhydride treatment: Using simple models of polymeric wood compounds
2008 - IRG/WP 08-30457
Treatment of wood by a mixed aceto/oleic (or other fatty acid residue) anhydride promoted as a safe and environment friendly wood preservation system has been examined quantitatively by liquid phase 13C NMR and solid phase MAS-DEC (proton decoupling) 13C NMR through all its different stages to determine which reactions occur with simple model compounds of the polymeric constituents of wood. The p...
F Lyon, M-F Thevenon, A Pizzi, G Tondi, A Despres, J Gril, S Rigolet
The decay resistance of chemically modified aspen composites to the white rot fungus Coriolus versicolor (L.) Quelet
1998 - IRG/WP 98-40122
Chemical modification of Aspen wood (Populus tremula L.) in the form of solid wood, veneers and sawdust was undertaken by a two step procedure consisting of esterification with maleic anhydride (MA) and subsequent oligoesterification with MA and glycidyl methacrylate (GMA) or allyl glycidyl ether (AGE). Modified wood was thermoplastic and was thermally formed by hot-pressing to produce veneer or s...
M C Timar, A J Pitman, M D Mihai
Durability of pine modified by 9 different methods
2004 - IRG/WP 04-40288
The decay resistance was studied for pine modified by nine methods of wood modification: 1) Acetylation, 2) Treatment with methylated melamine resin (MMF), 3) Acetylation followed by post-treatment with MMF-resin, 4) Thermal modification, 5) Furfurylation, 6) Maleoylation (using water solution of MG or ethanol solution of maleic anhydride), 7) Succinylation, 8) NMA-modification and 9) modification...
M Westin, A O Rapp, T Nilsson
Efficacy of anhydrides as wood protection chemicals - II. Performance against soft rot fungi
1998 - IRG/WP 98-30174
Pine sapwood modified with various anhydrides and with butyl isocyanate was tested for its resistance to soft rot decay. Small stakes were exposed for 20 months in unsterile soil in a fungal cellar test.
Wood modified with butyl isocyanate performed better than any of the anhydrides tested, with a threshold level of protection (less than 3% weight loss) at 12% weight percent gain (WPG). Stakes ac...
S C Forster, M D C Hale, G R Williams
Methods of treatment of wood preservatives. The selection of appropriate preservation process with particular reference to mixed tropical forest resources. A key address
1982 - IRG/WP 3177
All wood is biodegradable. Many timber species have, however, sufficient natural durability to permit their use, particularly in protected situations, without any special precautions. Many others, of course, are readily attacked by insects and where there is sufficient moisture and air, by wood-decaying fungi. It is these timber species which benefit most from treatment with wood preservatives. Ev...
C R Levy
Results from soft rot tests in vermiculite jars
1976 - IRG/WP 272
T Vihavainen
The distribution of introduced acetyl groups and a linseed oil model substance in wood examined by microautoradiography and ESEM
2000 - IRG/WP 00-40169
Microautoradiography, a photographic method that shows the localization of substances labelled with radioactive isotope, and Environmental Scanning Electron Microscopy (ESEM) were combined to enhance sensitivity, resolution and reliability for examination of the distribution of introduced substances in wood. The preparation of microautoradiographs is less complicated when investigated with ESEM an...
M Rosenqvist
Variation in infection rates of blue-stain, mould and white rot tropical fungi on mixed light Malaysian woods
2000 - IRG/WP 00-10334
The modified 3-week FRIM laboratory method for screening of anti-sapstain formulations against three representative tropical fungi causing blue-stain (Botryodiplodia theobromae), mould (Paecilomyces variotii) and white rot (Schizophyllum commune) infection of sapwood species was used to examine the relative resistance of the sapwood of eight mixed light Malaysian woods, Scots pine (Pinus sylvestri...
A H H Wong, S Ahmad
Improvements of stability and durability of beechwood (Fagus sylvatica) by means of treatment with acetic anhydride
1991 - IRG/WP 3645
In the present investigations, beechwood (Fagus sylvatica) was treated with non-catalysed acetic anhydrid at 120°C and some physical- and biological parameters of the treated wood were compared with those of non-treated wood. The radial and tangential shrinkage and swelling, respectively, and the absorption capacity of the acetylated wood against moisture is considerably lower. The durability aga...
H Militz
Laboratory evaluation of termite resistance of five lesser-known Malaysian hardwoods used for roof and ceiling construction
2001 - IRG/WP 01-10398
The general laboratory procedure of AWPA E1-97 was used to evaluate the termite resistance of 5 lesser- known species (LKT) of Malaysian hardwoods: Kekatong (Cynometra sp.), Kelat (Eugenia spp.), Mempening (Lithocarpus spp.), Perah (Elateriospermum tapos) and Pauh Kijang (Irvingia malayana) against the subterranean termite Coptotermes curvignathus over 28 days. Kempas (Koompassia malaccensis) and ...
A A H Wong, Kee Suan Cheok, J K Grace
The biological effectiveness of wood modified with heptadecenylsuccinic anhydride against two brown rot fungi: Coniophora puteana and Gloeophyllum trabeum
1992 - IRG/WP 92-3705
A modified soil block test was carried out using wood samples reacted with heptadecenylsuccinic anhydride (ASA). This modification gave good resistance to decay brought about by the brown rot fungi Coniophora puteana and Gloeophyllum trabeum during the twelve week exposure period. Results indicated that there was a good correlation between increased loading of modifying reagent and an increase in ...
C Codd, W B Banks, J A Cornfield, G R Williams
Use of mixed populations of microflora to control sapstain on radiata pine
2002 - IRG/WP 02-10427
Most methods of biological control in the wood products field have focused on the use of single species of fungi or bacteria to control sapstain or decay. The approach taken in this study involved applying soil microorganisms, in combination with nutrients and various adjuvants that collectively form the biological control system.
Radiata pine branch discs, autoclaved or fresh, were dipped in ...
C Chittenden, R Wakeling, B Kreber
Dimensional stability and decay resistance of wood upon modification with some new type chemical reactants
1994 - IRG/WP 94-40028
Solid wood of home grown species can be upgraded by chemical modification with environmentally acceptable chemicals. The best kwown example of modification reaction is acetylation with acetic anhydride. A continued search for reactive chemicals other than acetic anhydride is ongoing, aiming at the improvement of technical properties of wood. This contribution deals with the results of a screening ...
P Goethals, M Stevens
The kinetics of anhydride modification reactions of wood. Experimental results and theoretical modelling
1998 - IRG/WP 98-40125
Although the chemical modification of wood remains a fertile area for research, there has been little work performed on the kinetics of the modification process. The reaction kinetics of a series of linear chain and cyclic anhydrides has been studied and activation energies of the reaction determined. The reaction kinetic profiles are determined by the relative rates of reaction of the reagent wit...
C A S Hill, J G Hillier
Protection of a low-density mangrove timber species gewa (Excoecaria agallocha) through preparation of particleboard – An Assessment
2006 - IRG/WP 06-40348
It is now well established that the conversion of low-density and low-cost timbers into laminated, composite and densified form is an alternative of wood protection by means of wood preservatives. Once only the timber species gewa (Excoecaria agallocha) was used for manufacturing newsprint paper in Bangladesh, which is not continued today. The feasibility of commercial production of particleboard ...
A A Mahfuz, M O Hannan, M A Islam, M N Islam , M M Islam, A K Lahiry
Evaluation of natural durability of solid wood and mixed heartwood-sapwood Cypress (Cupressus sempervirens L.) plywood against Basidiomycete fungi
2008 - IRG/WP 08-10645
The aim of this research was to study the response of mixed plywoods composed of durable heartwood and non-durable sapwood to fungal attack. For this purpose, the species of Cupressus sempervirens (cypress) was chosen for its well-known durable heartwood. The evaluation of durability of plywood panels against fungi was done according to ENV 12038 and the fungi used were Coriolus versicolor (CV) an...
F Faraji, M F Thévenon, N Lemenager, B Thibaut
Decay resistance of propionylated Iranian beech against the white rot fungus Tramets versicolor
2008 - IRG/WP 08-30449
In this study, the decay resistance of propionylated beech was investigated against the white rot fungus Trametes versicolor. Iranian beech (Fagus orientalis) was modified with propionic anhydride at different temperatures, concentrations and times without using any catalyst. Different weight percentage gains (WPGs) were obtained under different conditions. The decay resistance of the esterifed wo...
M R M Farahani, S M Hosseini
Chemical modification of Scots Pine Sawdust by mixed anhydrides
2008 - IRG/WP 08-40439
By making react mixtures containing acetic-fatty anhydrides on Scots pine sawdust (SPS) without any solvent or catalyst; we synthesized mixed acetic-fatty esters of SPS. Such mixtures were synthesized by reaction between a carboxylic acid and acetic anhydride. These mixtures were obtained after reaction of acetic anhydride and a fatty acid that yields at equilibrium a mixture of five compounds: ac...
J Peydecastaing, E Borredon, S El Kasmi
Termite resistance of pure and mixed heartwood-sapwood Cypress (Cupressus sempervirens L.) plywoods
2009 - IRG/WP 09-10693
The main objective of this research was to evaluate the ability of different plywoods made of durable heartwood and/or non-durable sapwood to resist termite damage. The well-known durable cypress (Cupressus sempervirens) was chosen for this study. The natural durability of cypress solid wood, divided into sapwood and heartwood, as well as the durability of 17 different laboratory manufactured plyw...
F Faraji, M-F Thévenon, B Thibaut
A survey of factors affecting decay resistance of wood modified with acetic anhydride
2012 - IRG/WP 12-40594
From the range of information published, acetylation appears well suited to provide adequate protection against biological attack for materials derived from typically non-durable wood species. Acetylated wood is now commercially available both in Europe and in the USA. But still there are a lot of unanswered questions related to fungal decay mechanisms in acetylated wood. The paper summarize exist...
G Alfredsen, P O Flæte, H Militz
Copolymers of tannin extracts as wood protection agents
2017 - IRG/WP 17-30709
Wouldn´t be a dream to preserve wood with the substances which the nature already synthesizes for protecting itself? The idea we would like to pursue is simple: Increase the concentration of these substances, the tannins, trying to fix them properly in wood. It appears easy but it is not. Sensibility against leaching, fungal decay and weathering were observed. In this paper new flavonoid co-polym...
G Tondi, L Sommerauer, A Oberle, A Petutschnigg, M-F Thevenon
Accessibility of hydroxyl groups in anhydride modified wood as measured by deuterium exchange
2017 - IRG/WP 17-40784
Acetylated wood shows improved properties largely due to the reduced amount of water in the acetylated cell wall. However, the exact mechanism by which water is excluded in acetylated wood remains unclear. Acetylation reduces hydroxyl content by substitution of hydroxyl groups in wood polymers but may also hinder access to unmodified hydroxyls by physical bulking. This work assesses hydroxyl acces...
G Beck, S Strohbusch, E Larnøy, H Militz, C Hill
Wood Hydrophobic Modification by Mixed Wax Emulsions
2018 - IRG/WP 18-40839
An environmental-friendly, economical and facile method to construct hydrophobic system for improving wood repellency was applied in this study. Using paraffin wax and carnauba mixed wax O/W emulsions can simultaneously fabricate continuous wax films and rough structures in wood internal and external surface under appropriate heat treatment. In the study, single and mixed wax emulsions of 4% solid...
C Chen, W Wang
Development of beech wood thermo-chemical modification treatments based on different vinylic derivatives of glycerol and polyglycerol
2019 - IRG/WP 19-40855
In this study, a combination between chemical and thermal wood modification has been investigated. Seven types of a low concentration of 10% aqueous additive solution of vinylicglycerol [glycerol-maleic anhydride (Gly-MA), glycidyl methacrylate (GM), and Glycerol methacrylate-maleic anhydride (GM/MA(2eq))], vinylicpolyglycerol [polyglycerol-maleic anhydride (PG-MA), polyglycerol methacrylate (PGM...
M Mubarok, S Dumarcay, H Militz, K Candelier, M-F Thevenon, P Gerardin
Investigations into the use of Maleic Anhydride/Sodium Hypophosphite as a Wood Modification Process
2020 - IRG/WP 20-40891
The formation of crosslinked bonds between wood constituents is believed to be an effective way to stabilize wood against wet conditions. The possibility to use maleic anhydride (MA) combined with sodium hypophosphite (SHP) as crosslinking agents was studied, using Scots pine sapwood and a model compound. The modified wood showed weight gain and bulking effect after treatment and subsequent Soxhle...
I Kim, D Jones, O Karlsson, D Sandberg, O N Antzutkin, F Ullah Shah