Your search resulted in 35 documents. Displaying 25 entries per page.
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
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
Resistance against basidiomycetes of 1,3-dimethylol-4,5-dihydroxy ethylene urea (DMDHEU)-modified plywood of Pinus sylvestris
2008 - IRG/WP 08-40398
Plywood produced with rotary-cut veneers of Pinus sylvestris impregnated with a solution of 1.3 M 1.3-dimethylol-4.5-dihydroxyethyleneurea (DMDHEU) and glued with a phenolic resin (Prefere 4976 DYNEA) were inoculated with Coniophora puteana, Coriolus versicolor and Pleurotus ostreatus, following the European standard ENV 12038. The specimens were leached following European standard EN 84. The re...
A Dieste, A Pfeffer, S Bollmus, H Militz
Experience Experience from over 20 years of field trials of resin treated wood – Marine borer resistance of MMF and DMDHEU modified wood
2021 - IRG/WP 21-10976
In 1999 a field test of Scots pine treated with MMF (Methylated Melamine Formaldehyde) resin and acetylated Scots pine post treated with MMF resin was started. Six years later a commissioned full NWPC test for BASF of Belmadur® (DMDHEU resin treated wood) was started at the same site. The testing, according to European Standard EN 275, was done in a bay by Kristineberg Marine Research Station o...
M Westin, P Larsson Brelid, A O Rapp, J Habicht
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 f...
S Yusuf, Y Imamura, M Takahashi, K Minato
Dimensional stabilization of wood with dimethylol compounds
1987 - IRG/WP 3412
This study showed that a substantial degree of dimensional stability can be imparted to wood by crosslinking with low concentrations of dimethyloldihydroxyethyleneurea. It was demonstrated that by selecting the right catalyst system the cure temperature can be reduced to the point that strength loss of the treated wood is minimized....
D D Nicholas, A D Williams
Biological degradation resistance of pine wood treated with dimethylol compounds
1989 - IRG/WP 3528
The study reports the increase of dimensional stability and biological degradation resistance of pine wood (Pinus sylvestris L) after impregnation with dimethyloldibydroxyethyleneurea. Decay resistance was determined according to BS 838:961. Nearly complete protection against Coniophora puteana, (Schum.ex Fr. Karst) weight loss of 2-3% was shown when modification, expressed as weight gain, exceede...
C L Videlov
Novel wood modification processes for window and cladding products
2004 - IRG/WP 04-40285
Because of the low natural durability and low dimensional stability of European wood species, the usage of wood for window frames has decreased dramatically during the last decade. In a joint project of several German research institutes and the window industry, following wood modification systems were compared. heat treatment (3 different materials from 2 companies) acetylation (pine sapwood an...
A Krause, C Hof, H Militz
Evaluating the potential of modified wood for use in marine environments using a short-term laboratory bioassay
2004 - IRG/WP 04-10525
Chemically modified wood may be an alternative to preservative treated timber for marine structures. In this study a screening laboratory test using the wood-boring isopod crustacean Limnoria quadripunctata was used to assess the durability of chemically modified Pinus sylvestris, Pinus radiata and Picea sp. Most of the treatments used a combination of one of two of types of the resin dimethyloldi...
L M S Borges, S M Cragg, M van der Zee
Influence of concentration, catalyst, and temperature on dimensional stability of DMDHEU modified scots pine
1998 - IRG/WP 98-40119
Dimethyloldihydroxyethyleneurea (DMDHEU) is being used in textile industry to improve wrinkle recovery. Trials on solid wood have been performed to minimise swelling of the wood. This paper focuses on the effect of various types and concentrations of catalyst and reaction temperature on the dimensional stability of Scots pine. Three different catalysts, NKS (based on magnesium chloride), 3282 (bas...
M Van der Zee, E P J Beckers, H Militz
Curing conditions for a low formaldehyde etherificated melamine resin
1998 - IRG/WP 98-40108
Waterbased methanol etherificated melamine formaldehyde resins have the potential to increase the resistance of impregnated wood against wood destroying fungi. Previous studies indicated that the resin with the lowest formaldehyde content tested showed the best results regarding fungal resistance, dimensional stability and formaldehyde emissions after curing. In the present paper the influence of ...
D Lukowsky, R-D Peek, A O Rapp
Effect of aqueous polymer treatments on wood properties. Part 2: Mechanical properties
1990 - IRG/WP 3611
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 static bending, toughness, and hardness were conducted on matched treated and untreated pieces according to ASTM Standards. Properties of pine were not affected by treatment with the po...
Z Ashaari, H M Barnes, D E Lyon, R C Vasishth, D D Nicholas
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
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...
Blue Staining of Coated Modified and Unmodified Wood
2006 - IRG/WP 06-10589
We investigated resistance of unmodified, DMDHEU modified and oil heat treated uncoated and coated Scots pine wood against blue stain fungi. Both EN 152-1 and the reverse exposure tests showed excellent resistance of DMDHEU and especially of oil heat treated wood against blue staining. It is not needed to add any additional protective coating layers to prevent modified wood from staining. However,...
M Petric, M Pavlic, M Humar, M Tomažic
Resistance of DMDHEU-treated pine wood against termite and fungi attack in field testing according to EN 252. Results after 30 months
2006 - IRG/WP 06-40354
The aim of this study was to determine the effectiveness against decay and termite attack of pine sapwood treated with pure and modified DMDHEU in a field test according to European Standard EN 252. Some of the treatments tested were able to increase, within the period of the test reported (30 months), the resistance of the wood both to micro-organisms and termites. The curing process seems to be ...
S Schaffert, L Nunes, A Krause, H Militz
Termite resistance of DMDHEU-treated wood
2008 - IRG/WP 08-40401
Chemical wood modification with dimethyloldihydroxy-ethyleneurea (DMDHEU) or its derivatives are applicable to both solid lumber and wood-based composites. Advantages of DMDHEU-based modification are an increase of dimensional stability and high durability against white, brown and soft rot fungi. At higher chemical loadings, the hardness of the wood is considerably increased. Due to the durabil...
H Militz, S Schaffert, B C Peters, C J Fitzgerald
Termite resistance of some modified wood species
2009 - IRG/WP 09-40449
During the last few decades, researchers worldwide have investigated and developed new treatment techniques to improve intrinsic wood properties. Some of these techniques were introduced to the market recently and are gaining in importance.. Various wood properties of these new materials have been studied intensively. These include physical-mechanical properties (dimensional stability, moisture ...
H Militz, B C Peters, C J Fitzgerald
Weathering of Wood Modified with the N-Methylol Compound 1,3‑dimethylol-4,5-dihydroxyethyleneurea (DMDHEU)
2009 - IRG/WP 09-40467
Scots pine (Pinus sylvestris L.) sapwood boards were treated with a methylated 1,3‑dimethylol-4,5-dihydroxyethyleneurea (mDMDHEU) causing weight gains of approx. 25% and exposed to weathering for 18 months. Compared to untreated boards, treatment with mDMDHEU reduced surface discoloration mainly caused by staining fungi. Boards treated with mDMDHEU exhibited clearly lower moisture content th...
C Mai, Yanjun Xie, A Krause, K Urban, P D Evans, K Richter, H Militz
Protection mechanisms of modified wood against decay by white and brown rot fungi
2010 - IRG/WP 10-10713
The resistance of beech and pine wood blocks treated with 1,3-dimethylol-4,5-dihydroxyethylene urea (DMDHEU) against T. versicolor and C. puteana increased with increasing WPG. Full protection (mass loss below 3%) was reached at WPGs of approximately 15% (beech) and 10% (pine). Metabolic activity of the fungi in the wood blocks was assessed as heat or energy production determined by isothermal mic...
C Mai, P Verma, Yanjun Xie, J Dyckmans, H Militz
The Effects of Some Fire Retardant Chemicals on the Decay Resistance of Medium Density Fiberboard (MDF)
2010 - IRG/WP 10-30536
The objective of this study was to determine the decay resistance of Medium Density Fiberboard (MDF) treated with 5% and 10% concentration of various fire retardant (FR) chemicals. Experimental panels were produced using by melamine-urea-formaldehyde (MUF) resins having 10%, 15% and 20% of melamine content. MDF specimens were subjected to decay resistance test performed according to modified EN 11...
D Ustaömer, M Usta, Ü C Yildiz, S Yildiz, E D Tomak
Effect of 4 Preservatives on Physical, Mechanical and Mold-Resistant Properties of Bamboo Oriented Strand Boards
2010 - IRG/WP 10-40483
This study investigated the effects of 4 preservative systems on physical, mechanical and mold-resistant properties of bamboo oriented strand board (OSB) panels bonded with urea formaldehyde resin. Preservative A (Zinc Borate), B (IPBC), C (AAC+Borate) and D (carbendazim + prochloraz) were incorporated with strands during blending at three loading levels. The results showed that the mechanical and...
Juwan Jin, Daochun Qin, Wanshu Wei, Kuan Fan
Effect of borax-boric acid Treatment of simul (Bombax ceiba) Veneers on Glue-Bond Quality of Plywood
2010 - IRG/WP 10-40525
The glue-bond quality of plywood made of treated simul (Bombax ceiba) veneers was investigated. The veneers were treated with cold and hot water solution of borax-boric acid (BB) of different concentrations and treatment durations. The plywoods were made at three different pressures in hot press using urea formaldehyde glue. The glue-bond strength of untreated plywood in dry shear-test was found t...
K Akhter, Md Abul Hashem, S Akhter
Multilayer hot-press drying and chemical modifying of poplar wood with urea-formaldehyde prepolymer
2011 - IRG/WP 10-40539
The objective of this study was to determine the technology of chemical modifying and multilayer hot-press drying on poplar wood. The chemicals were impregnated into cell lumen space by pulse-dipping machine to improve the dimension stability and mechanical property of timber. The timbers were compressed and dried by the multilayer hot-press drying to increase the density of timber. Results indica...
Guofeng Wu, Yifei Jiang, Sheng Yao, Junwen
Biological and mechanical performances of particleboard panels made from maritime pine (Pinus pinaster) and glued with cornstarch-mimosa tannin-urea formaldehyde adhesive
2011 - IRG/WP 11-40542
The objective of this work was to demonstrate the utility of cornstarch-mimosa tannin-based resins designed for application as an adhesive in the particleboard production. Bond qualities of cornstarch-mimosa tannin- urea formaldehyde (UF) (10:4:86, weight ratios) resins and commercial UF resin were assessed by using an automatic bonding evaluation system, prior to production of particleboard panel...
A Moubarik, F Charrier, A Pizzi, A Allal, B Charrier