An innovative method for the chemical modification of Carpinus betulus wood: a methodology and approach study

AbstractThe objective of this research was to evaluate the influence of acetyl and methyl bonds on the physical, mechanical, photochemical and biological resistance properties of hornbeam wood.Carpinus betulus(hornbeam) wood is considered to be a less valuable species due to poor durability. In order to improve its properties, a novel and simple method was applied to modify wood samples. Hence, wood samples were modified by either acetylation or methylation at four treatment levels. Reactions between hornbeam wood and the formalin and acetic acid treatment system were successful as exemplified by increased mass [weight percent gain (WPG)], slightly better compression strength and considerably improved impact bending strength. Furthermore, the biological decay resistance of the treated wood samples increased for all of the treatments.

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Protection mechanisms of DMDHEU treated wood against white and brown rot fungi

Holzforschung ◽

10.1515/hf.2009.051 ◽

2009 ◽

Vol 63 (3) ◽

Cited By ~ 30

Author(s):

Pradeep Verma ◽

Ulrich Junga ◽

Holger Militz ◽

Carsten Mai

Keyword(s):

Cell Wall ◽

Treated Wood ◽

Weight Percent Gain ◽

Brown Rot ◽

Weight Percent ◽

Decay Resistance ◽

Brown Rot Fungi ◽

Protection Mechanisms ◽

Mesh Bags ◽

Fine Wood

AbstractThe resistance of beech and pine wood blocks treated with 1,3-dimethylol-4,5-dihydroxyethylene urea (DMDHEU) againstTrametes versicolorandConiophora puteanaincreased with increasing weight percent gain (WPG) of DMDHEU. Full protection [mass loss (ML) below 3%] was reached at WPGs of approximately 15% (beech) and 10% (pine). Untreated and DMDHEU treated blocks were infiltrated with nutrients and thiamine prior to fungal incubation and it was observed whether the destruction or removal of nutrients and vitamins during the modification process has an influence on the ML caused by the fungi. This study revealed that no considerable differences were found. Then, the cell wall integrity was partly destroyed by milling and the decay of the fine wood powder filled into steel mesh bags was compared to that of wood mini-blocks. The purpose of this study was to examine whether the effects of surface area, cell wall bulking, and reduction in micro-void diameters play a role in decay resistance. The ML caused by the fungi, however, also decreased with increasing WPG and showed comparable patterns similar to the case of mini-blocks. ML of powder bearing the highest WPG appeared to be caused by losses in DMDHEU during fungal incubation. For brown rotted wood, the infrared absorption ratios at 1030 cm-1and 1505 cm-1revealed decreasing decay of polysaccharides with increasing WPG of treated wood.

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Effect of short-chain silicones bearing different functional groups on the resistance of pine (Pinus sylvestris L.) and beech (Fagus sylvatica L.) against decay fungi

Holzforschung ◽

10.1515/hf-2012-0065 ◽

2013 ◽

Vol 67 (4) ◽

pp. 447-454 ◽

Cited By ~ 7

Author(s):

Malte Pries ◽

Roland Wagner ◽

Karl-Heinz Kaesler ◽

Holger Militz ◽

Carsten Mai

Keyword(s):

Mass Loss ◽

Functional Groups ◽

Beech Wood ◽

Treated Wood ◽

Weight Percent Gain ◽

Weight Percent ◽

Fungal Resistance ◽

Short Chain ◽

Cross Sectional ◽

Decay Fungi

Abstract Blocks of pine sapwood and beech wood were treated with water-based emulsions containing short-chain silicones with different α-ω-bonded functional groups, such as diamino, carboxyl and carbonyl, betain, and epoxy groups. The weight percent gain upon treatment of the pine wood specimens was relatively high (10%–20%), but their cross-sectional bulking was low (1%–2.5%). Thus, the anti-shrink efficiency (ASE) due to the treatment was also low. The first water-submersion tests revealed some hydrophobation of the treated wood. A second submersion test, however, revealed successful hydrophobation only for betain-functionalised material. The carboxylated silicone even increased the speed of water uptake as compared to the controls. The samples treated with silicones bearing epoxy, diamino, and carboxy functionalities showed a distinct reduction in mass loss compared to the control samples after 16 weeks of incubation with the fungi Coniophora puteana and Trametes versicolor according to EN 113 and CEN/TS 15083-1, whereas the betain-functionalised silicone did not enhance fungal resistance. All silicones tested lowered the mass loss in a soft rot test according to ENv 807. The mode of action of the silicones is discussed.

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Influence of Copper and Biopolymer/Saqez Resin on the Properties of Poplar Wood

Forests ◽

10.3390/f11060667 ◽

2020 ◽

Vol 11 (6) ◽

pp. 667 ◽

Cited By ~ 1

Author(s):

Huijun Dong ◽

Mohsen Bahmani ◽

Sohrab Rahimi ◽

Miha Humar

Keyword(s):

Physical Properties ◽

Trametes Versicolor ◽

Weight Percent Gain ◽

Weight Percent ◽

Decay Resistance ◽

White Rot ◽

White Rot Fungus ◽

Poplar Wood ◽

Wood Protection ◽

Increasing Trend

There is an increasing trend in the use of environmentally-friendly materials in wood protection. This includes the use of less toxic active ingredients, as well as better fixation. This study investigates the formulation based on the combination of copper and Saqez resin on the physical and biological resistance properties of poplar wood. Samples were treated by either copper-ethanolamine (Cu/MEA) and/or Saqez resin at various treatment levels. A vacuum pressure procedure was applied. The retention, weight percent gain, water absorption, volumetric swelling, and decay resistance of the samples were then determined. The highest retention and weight percent gain were obtained in the samples treated with the combination of copper-based system and Saqez resin. Additionally, the combination of the copper and Saqez improved the physical properties and decay-resistance against white-rot fungus Trametes versicolor.

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Beech wood treated with polyglycerol succinate: a new effective method for its protection and stabilization

Holzforschung ◽

10.1515/hf-2019-0060 ◽

2020 ◽

Vol 74 (4) ◽

pp. 351-361 ◽

Cited By ~ 4

Author(s):

Clément L’Hostis ◽

Emmanuel Fredon ◽

Marie-France Thévenon ◽

Francisco-José Santiago-Medina ◽

Philippe Gérardin

Keyword(s):

Beech Wood ◽

Treated Wood ◽

Weight Percent ◽

Decay Resistance ◽

Curing Temperature ◽

Ionization Time ◽

Chemical Structures ◽

Treatment Conditions ◽

Middle Infrared

AbstractThis paper deals with an original and non-biocidal chemical treatment consisting of a vacuum/pressure impregnation step of beech wood with a water-borne mixture made from heat-activated condensation of succinic anhydride (SA) and glycerol (G). Chemical structures of adducts were established using matrix-assisted laser desorption ionization time-of-flight mass spectroscopy (MALDI-TOF) investigations. Beech wood was impregnated and cured in order to induce in situ polymerization of glycerol/succinic adducts (GSA) in the cell walls, leading to the formation of polyglycerol succinate (PGS) polyester. Various treatment conditions were investigated depending on the duration (6–72 h) and curing temperature (103–160°C). Weight percent gains (WPGs) ranging between 40 and 60% were obtained. Attenuated total reflectance-middle infrared spectroscopy (ATR-MIR) and carbon-13 nuclear magnetic resonance (13C-NMR) spectroscopy confirmed polyester formation. A curing temperature of 160°C was found to be the best condition to totally avoid polymer leaching, and brought the anti-swelling efficiency (ASE) up to 64%. Decay resistance of PGS-treated wood against Trametes versicolor and Coniophora puteana was also strongly temperature and time dependent: performances fit with the EN113 standard requirements if a curing temperature of 160°C was applied.

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Evaluation of water related properties of birch wood products modified with different molecular weight phenol-formaldehyde oligomers

Holzforschung ◽

10.1515/hf-2020-0235 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Juris Grinins ◽

Vladimirs Biziks ◽

Janis Rizikovs ◽

Ilze Irbe ◽

Holger Militz

Keyword(s):

Molecular Weight ◽

Dimensional Stability ◽

Phenol Formaldehyde ◽

Treated Wood ◽

Weight Percent Gain ◽

Weight Percent ◽

Solid Wood ◽

Wood Products ◽

Birch Wood ◽

Molecular Weights

Abstract This study investigated the effect of phenol-formaldehyde (PF) resin treatment on the dimensional stability of birch solid wood and plywood. Therefore, three different low molecular weight PF resins with average molecular weights (M w ) of 292, 528, and 884 g/mol were synthesized and used for silver birch (Betula pendula) solid wood (20 × 20 × 20 mm3) and veneer (100 × 100 × 1.4 and 300 × 300 × 1.4 mm3) impregnation to produce plywood. The weight percent gain (WPG) and bulking after curing of resin treated wood specimens were determined. The leaching was performed to evaluate the PF resin fixation stability. All tested resins at all concentrations were similarly fixed in wood blocks after the leaching (1.5–2.0% WPG loss). The dimensional stability of birch wood after treatment with all tested PF resins was significantly improved. The anti-swelling efficiency (ASE) of birch wood blocks treated with PF resins after seven water soaking-drying cycles was in the range of 39–53%, 46–65% and 49–65% using 10, 15 and 20% solution concentrations, respectively. Whereas, the ASE of plywood obtained from veneers treated with 10% of PF solution was improved by 6–20%. The equilibrium moisture content (EMC) and volumetric swelling (VS) of PF treated plywood at 98% of relative humidity (RH) decreased significantly. All PF resin treated plywood surfaces were more hydrophobic compared to untreated plywood.

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Influence of Copper and Biopolymer/Saqez Resin on the Properties of Poplar Wood

10.20944/preprints202005.0131.v1 ◽

2020 ◽

Author(s):

Huijun Dong ◽

Mohsen Bahmani ◽

Sohrab Rahimi ◽

Miha Humar

Keyword(s):

Physical Properties ◽

Trametes Versicolor ◽

Weight Percent Gain ◽

Weight Percent ◽

Decay Resistance ◽

White Rot ◽

White Rot Fungus ◽

Poplar Wood ◽

Wood Protection ◽

Protection Technology

There is an increasing interest in applying environmentally-friendly materials in wood protection technology. This include the use of less toxic active ingredients, as well as better fixation. This study investigates the formulation based on the combination of copper and Saqez resin on the physical and biological resistance properties of poplar wood. Samples were treated by either copper-ethanolamine (Cu/MEA) and/or Saqez resin at various treatment levels. A vacuum pressure procedure was applied. The retention, weight percent gain, water absorption, volumetric swelling, and decay resistance of the samples were then determined. The highest retention and weight percent gain were obtained at the samples treated with the combination of copper-based system and Saqez resin. Additionally, the combination of the copper and Saqez improved the physical properties and decay-resistance against white-rot fungus Trametes versicolor.

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Physical, mechanical, and decay resistance properties of heat-treated wood by Besson® process of three European hardwood species

BASE - Numéro 3 ◽

10.25518/1780-4507.19050 ◽

2021 ◽

pp. 129-139

Author(s):

Maxime Ninane ◽

Caroline Pollet ◽

Jacques Hébert ◽

Benoit Jourez

Keyword(s):

Heat Treatment ◽

Axial Compression ◽

Modulus Of Elasticity ◽

Treated Wood ◽

Decay Resistance ◽

Strength Increase ◽

Promising Alternative ◽

Hardwood Species ◽

Heat Treated ◽

Impact Bending

Description of the subject. In Europe, the heat treatment of native wood species is gradually becoming an industrial reality. It provides a promising alternative to both the use of naturally durable, essentially tropical woods and the use of chemical preservative treatments based on biocides. Objectives. The aim of this study is to quantify the effect of heat treatment on the physico-mechanical and decay resistance properties of three native hardwood species (oak, ash, beech + steamed beech). Method. The wood was heat-treated in accordance with the Besson® process. The standard physical and mechanical tests including hardness, modulus of elasticity in static bending, static bending, axial compression, splitting and impact bending strengths, have been performed on 15 treated and 15 control associated samples for each species. The standard durability test on fungi exposed 60 treated and 60 control samples to each fungus. Results. The results show a decrease in the equilibrium moisture content and an increase in dimensional stability of heat-treated wood for the three species studied. The modulus of elasticity, hardness and axial compression strength increase slightly after the heat treatment, while static and impact bending strength and splitting strength may considerably decrease. The fungal durability of oak heartwood and ash increased until class 1, beech and steamed beech until class 3. Conclusions. The global approach of this study allows a complete and precise characterization of the technological properties of three native hardwood species after heat treatment. New uses of these native species can thus be explored.

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Water Related Properties of Birch Wood Modified with Phenol-Formaldehyde (PF) Resins

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.800.246 ◽

2019 ◽

Vol 800 ◽

pp. 246-250

Author(s):

Juris Grinins ◽

Vladimirs Biziks ◽

Ilze Irbe ◽

Janis Rizhikovs

Keyword(s):

Phenol Formaldehyde ◽

Treated Wood ◽

Weight Percent Gain ◽

Weight Percent ◽

Solid Wood ◽

Specimen Size ◽

Fixation Stability ◽

Resin Loading ◽

The Impact ◽

Leaching Procedure

In this study, Silver birch (Betula pendula) wood veneers and solid wood blocks were treated with commercial phenol-formaldehyde (PF) resin water solutions. Birch veneers and solid wood blocks of different size were impregnated with PF resin solutions in water with concentrations of 10, 20 and 30 wt%. The weight percent gain (WPG) and bulking after drying and curing of resin treated wood specimens were determined to evaluate the impact of specimen sizes and density. The leaching procedure according to EN 84 was performed to evaluate the PF resin fixation stability. The anti-swelling efficiency (ASE) of untreated and treated specimens during seven soaking-drying cycles was examined. Higher WPG values were obtained for specimens with lower density, but no correlation was found between the specimen size and WPG. The WPG of veneers and solid wood was 8.7 - 17.7% and 8.5 - 24.4%, respectively. The ASE of wood blocks treated with PF resins after the 1st cycle was in the range of 37 - 51% depending on the resin loading in the wood. However, the ASE values decreased after every next soaking-drying cycle, reaching 33 - 48% after the 7th cycle. After leaching, the WPG of specimens decreased by 2.3 - 3.0%.

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Furfural-based resin for modifying birch wood properties

BioResources ◽

10.15376/biores.16.4.7139-7160 ◽

2021 ◽

Vol 16 (4) ◽

pp. 7139-7160

Author(s):

Marzieh Sharifat ◽

Davood Efhamisisi ◽

Marie-France Thevenon ◽

Asghar Tarmian ◽

Mehdi Jonoobi

Keyword(s):

Treated Wood ◽

Weight Percent Gain ◽

Wood Properties ◽

Weight Percent ◽

Modulus Of Rupture ◽

Accelerated Weathering ◽

Treatment Technology ◽

Loaded Resin ◽

Resin Curing ◽

The Impact

Furfural (F) cannot be easily polymerized like furfuryl alcohol, but it is an aldehyde that can react with urea (U) to make a polymeric network. The possibility of preparing F/U polymer along with an acidic catalyzer (maleic anhydride; M) was evaluated as a means to improve some selected properties of birch (Betula pendula) wood. The F+U/M resin was introduced into the wood with a double treatment technology. The first step involved dilution of F in water and methanol, and the second step was immersion in a U/M aqueous solution. The color of treated wood was darkened after resin curing from brown to a spectrum of black depending on the amount of loaded resin. The 60 to 80% of materials were converted to a non-leachable polymer based on the different formulations. The water absorption and volumetric swelling of the treated samples decreased with an increase in weight percent gain (WPG). The analysis of mechanical strength showed that treatment with F + U/M reduced to some extent the hardness and the impact bending of wood, while modulus of rupture, modulus of elasticity, and compression parallel to the grain with WPG were increased. The exposure of the samples to the accelerated weathering showed noticeable changes in color and roughness.

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The Analysis of Dimensional Changes Due to Chemical Treatments and Water Soaking for Hinoki (Chamaecyparis obtusa) Wood

Holzforschung ◽

10.1515/hf.2002.016 ◽

2002 ◽

Vol 56 (1) ◽

pp. 98-102 ◽

Cited By ~ 27

Author(s):

Kosuke Ohmae ◽

Kazuya Minato ◽

Misato Norimoto

Keyword(s):

Phenol Formaldehyde ◽

Treated Wood ◽

Untreated Wood ◽

Weight Percent Gain ◽

Weight Percent ◽

Chamaecyparis Obtusa ◽

Phenol Formaldehyde Resin ◽

Formaldehyde Resin ◽

Dimensional Changes ◽

Cell Lumen

Summary To clarify tangential and radial dimensional changes in hinoki (Chamaecyparis obtusa) wood by ten kinds of treatments and successive water soaking, a vector expression on the tangential-radial coordinates was proposed and a new measure (ASE′) to evaluate the dimensional stability of wood was defined. The ASE′ is expressed by 100(1 − Vs′ /Vu ) where Vu is the volumetric swelling coefficient of untreated wood and Vs′ is that of treated wood calculated on the basis of its oven-dried volume before treatment. The results from formaldehyde treated, heat treated and steam treated wood showed large positive ASE′ values and the ratio of radial swelling to tangential swelling (swelling anisotropy) of these treated woods decreased with increasing weight percent gain or weight loss. The results from acetylated wood, wood impregnated with polyethylene glycol and wood treated with a low molecular weight phenol-formaldehyde resin showed either small positive or negative ASE′ values, and those of wood treated with propylene oxide showed large negative values. The swelling anisotropy of treated woods accompanied by cell wall bulking was larger than that of untreated wood. The swelling anisotropy decreased when the cell lumen was filled with a hydrophobic resin (WPC-MMA), and increased when the cell lumen was filled with a hydrophilic resin (WPC-HEMA).

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