scholarly journals Furfural-based resin for modifying birch wood properties

BioResources ◽  
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.

Esterification of wood with citric acid: The catalytic effects of sodium hypophosphite (SHP)

Holzforschung ◽  
2014 ◽  
Vol 68 (4) ◽  
pp. 427-433 ◽  
Author(s):  
Xinhao Feng ◽  
Zefang Xiao ◽  
Shujuan Sui ◽  
Qingwen Wang ◽  
Yanjun Xie
Keyword(s):  
Citric Acid ◽  
Treated Wood ◽  
Wood Properties ◽  
Weight Percent ◽  
Point Of View ◽  
Modulus Of Rupture ◽  
Sodium Hypophosphite ◽  
Esterification Reaction ◽  
Water Leaching ◽  
Efficient Catalyst

Abstract Sodium hypophosphite (SHP) has been recognized as the most efficient catalyst in the esterification reaction of cellulosic fabrics with citric acid (CA), but both the high cost and the environmentally harmful property of SHP call for optimization of its application. In this study poplar wood (Populus adenopoda Maxim.) was treated with CA to various weight percent gains (WPGs) and the effect of SHP on the resulting properties of treated wood was investigated. Esterification with CA can occur also in the absence of SHP, as evidenced by the resistance to water leaching of CA. Wood treated with CA alone to 36% WPG exhibited 7% bulking, 50% anti-swelling efficiency, 30% reductions of the modulus of rupture, and 50% lower impact strength. Treatments with CA in the presence of SHP provided wood properties comparable to wood treated with CA alone. Thus the application of SHP can be questioned from the point of view of an economic production and environmental protection.

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

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%.

Radiata pine wood treatment with a dispersion of aqueous styrene/acrylic acid copolymer

Holzforschung ◽  
2018 ◽  
Vol 72 (5) ◽  
pp. 387-396 ◽  
Author(s):  
Wenbo Che ◽  
Zefang Xiao ◽  
Guanghui Han ◽  
Zhongguo Zheng ◽  
Yanjun Xie
Keyword(s):  
Acrylic Acid ◽  
Elevated Temperatures ◽  
Wood Quality ◽  
Surface Hardness ◽  
Treated Wood ◽  
Wood Properties ◽  
Weight Percent ◽  
Radiata Pine ◽  
Mechanical Reinforcement ◽  
The Impact

AbstractWood of radiata pine (Pinus radiataDon) was treated with an aqueous styrene/acrylic acid (St/AA) copolymer dispersion leading to weight percent gains (WPGs) of 10–42%. The reactivity of St/AA in wood and the modifying effects on wood properties were investigated. The St/AA precipitated in the cell lumens and condensed under catalysis at elevated temperatures was shown via scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. Treatment did not cause positive bulking efficiency and anti-swelling efficiency, because St/AA cannot diffuse into the cell walls due to its high molecular mass. The modulus of elasticity and rupture (MOE and MOR, respectively), and the surface hardness of the wood were improved by 24.4, 22.2, and 40.6%, respectively. Compression strength increased by 81.6 and 48.2% in radial and longitudinal directions, but the impact strength was hardly influenced by the treatment. In addition, the treated wood was slightly more hydrophobic than untreated controls as shown by reduced moisture content and water uptake. Accordingly, treatment with St/AA leads to mechanical reinforcement of wood and enhances its water resistance, and as a consequence, it has an application potential to improve the wood quality.

Effect of a Polymer Additive on Properties of Creosote-Treated Wood

2019 ◽  
Vol 69 (1) ◽  
pp. 96-100
Author(s):  
Daniel B. Trebelhorn ◽  
Byrne Miyamoto ◽  
Jeffrey J. Morrell ◽  
Jeffrey Ellis ◽  
Stacey McKinney
Keyword(s):  
Modulus Of Elasticity ◽  
Elasticity Modulus ◽  
Treated Wood ◽  
Water Repellency ◽  
Wood Properties ◽  
Modulus Of Rupture ◽  
Low Molecular Weight ◽  
Moisture Uptake ◽  
Polymer Additive ◽  
The Impact

Abstract The potential for using a low molecular weight polyethylene (PE) polymer to improve the properties of creosote-treated wood was evaluated on samples of six different wood species. Samples were impregnated with creosote alone or amended with the PE additive and then tested to failure in third-point loading to determine modulus of elasticity and modulus of rupture. Samples were then subjected to three soak–dry cycles to assess the impact of moisture uptake on fastener performance or water repellency. The presence of the PE was associated with lower preservative retentions, but had no significant effect on modulus of elasticity, modulus of rupture, water repellency, or fastener withdrawal resistance. The results suggest that the additive limited preservative uptake, but did not improve any of the wood properties evaluated.

scholarly journals Effect of Furfurylation on Hierarchical Porous Structure of Poplar Wood

Polymers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 32
Author(s):  
Xiaoshuang Shen ◽  
Pan Jiang ◽  
Dengkang Guo ◽  
Gaiyun Li ◽  
Fuxiang Chu ◽  
...  
Keyword(s):  
Porous Structure ◽  
Value Added ◽  
Untreated Wood ◽  
Weight Percent Gain ◽  
Wood Properties ◽  
Weight Percent ◽  
Acoustic Properties ◽  
Hierarchical Porous Structure ◽  
Wood Processing ◽  
Hierarchical Porous

Some wood properties (such as permeability and acoustic properties) are closely related to its hierarchical porous structure, which is responsible for its potential applications. In this study, the effect of wood impregnation with furfuryl alcohol on its hierarchical porous structure was investigated by microscopy, mercury intrusion porosimetry and nuclear magnetic resonance cryoporometry. Results indicated decreasing lumina diameters and increasing cell wall thickness of various cells after modification. These alterations became serious with enhancing weight percent gain (WPG). Some perforations and pits were also occluded. Compared with those of untreated wood, the porosity and pore volume of two furfurylated woods decreased at most of the pore diameters, which became more remarkable with raising WPG. The majority of pore sizes (diameters of 1000~100,000 nm and 10~80 nm) of macrospores and micro-mesopores of two furfurylated woods were the same as those of untreated wood. This work could offer thorough knowledge of the hierarchical porous structure of impregnatedly modified wood and pore-related properties, thereby providing guidance for subsequent wood processing and value-added applications.

Fabrication of highly stable and durable furfurylated wood materials. Part I: process optimization

Holzforschung ◽  
2020 ◽  
Vol 74 (12) ◽  
pp. 1135-1146
Author(s):  
Wanju Li ◽  
Minghui Liu ◽  
Hankun Wang ◽  
Yan Yu
Keyword(s):  
Orthogonal Experiment ◽  
Weight Percent Gain ◽  
Weight Percent ◽  
Chinese Fir ◽  
Curing Temperature ◽  
Modulus Of Rupture ◽  
Scale Production ◽  
Range Analysis ◽  
Decay Fungi ◽  
Mold Resistance

AbstractIn order to improve dimensional stability and durability of wood, furfurylation of poplar and Chinese fir wood using newly developed furfuryl alcohol (FA) formulation combined with a common vacuum and pressure impregnation process was studied. An orthogonal experiment was designed to optimize the furfurylation process for the two wood species. The weight percent gain (WPG), equilibrium moisture content (EMC), anti-swelling efficiency (ASE), modulus of rupture (MOR), modulus of elasticity (MOE), as well as resistance to mold, decay fungi, and termites were evaluated. The results showed that nearly all the properties of the furfurylated wood could be improved to various extents. The average ASE of the furfurylated Chinese fir and poplar could reach as high as 80, 71, 92% and 79, 90, 75% in tangential and radial directions, and by volume, respectively, higher than most previously reported wood modification processes. Furthermore, the modified wood had excellent biological durability, with nearly 100% mold resistance, strong decay and termite resistance. Finally, processing parameters with 50% FA, 105–115 °C curing temperature, and 5–8 h curing time were therefore recommended for pilot-scale production of furfurylated poplar and Chinese fir wood based on range analysis.

scholarly journals Characteristics of impregnated wood by nano silica from betung bamboo leaves

2021 ◽  
Vol 891 (1) ◽  
pp. 012019
Author(s):  
I Rahayu ◽  
A Pratama ◽  
W Darmawan ◽  
D Nandika ◽  
E Prihatini
Keyword(s):  
Mechanical Properties ◽  
Weight Percent Gain ◽  
Weight Percent ◽  
Modulus Of Rupture ◽  
Nano Silica ◽  
Bamboo Leaves ◽  
Silica Concentration ◽  
Average Size ◽  
Monoethylene Glycol ◽  
Colour Alteration

Abstract Abstract, Sengon (Falcataria moluccana Miq.) as a fast-growing wood species that has low quality. Therefore, wood modification is needed to improve its wood qualities. The objective of this study was to analyse the effect of monoethylene glycol (MEG) and nano silica of betung bamboo leaves impregnation treatment on physical, mechanical properties and durability of sengon wood. 5-years-old Sengon wood from community forest, MEG and nano silica (average size = 436.16 nm) from betung bamboo leaves were used. The impregnation solutions were consisted of water treated (untreated), MEG, MEGSilika 0.5% and MEGSilika 1%. Impregnation process with 0.5 bar (60 minutes) vacuum and 2.5 bar (120 minutes) pressure. Physical properties (density and colour alteration), mechanical properties (Modulus of Elasticity (MOE), Modulus of Rupture (MOR) and hardness) and durability against subterranean (Coptotermes curvignathus) attack. The results showed that the weight percent gain (WPG) and density of treated Sengon wood were increased as the nano silica concentration increased. While colour alteration (Δε) of treated samples were declining. Mechanical properties (MOE, MOR and hardness) were also improved. Durability based on laboratory tested against subterranean attack resulted that the percentage of termite mortality from the treated samples increased, while the percentage of weight loss decreased.

scholarly journals Effects of epyxilous fungus Laetiporus sulphureus (Bull. ex Fr.) murrill on the deccomposition of oak wood

2017 ◽  
pp. 21-30
Author(s):  
Miroslava Marković ◽  
Snežana Rajković ◽  
Mara Tabaković-Tošić ◽  
Marija Milosavljević
Keyword(s):  
Regression Line ◽  
Brown Rot ◽  
Wood Properties ◽  
Quercus Petraea ◽  
Modulus Of Rupture ◽  
Oak Wood ◽  
Brown Rot Fungi ◽  
Static Modulus ◽  
Laetiporus Sulphureus ◽  
The Impact

Testing samples were collected from the medulla of healthy oak trees in Eastern Serbia, from the association of Quercetum montanum. Over the periods of 2, 4 and 6 months the wood samples were exposed to influence of the mycelia of the fungus causing cubical brown rot on oak. Given that static modulus of rupture provides the quickest and clearest way to observe destruction caused by epixylous fungi, this paper researched the decrease in modulus of rupture of Sessile oak wood due to influence of causers of cubical brown rot. The samples have been exposed to the impact of the mycelia of the brown rot fungus on oak tree Laetiporus sulphureus (Bull. ex Fr.) Murrill (Sulphur Polypore). Effect of to the impact of the brown rot fungi was investigated, in decrease of static modulus of rupture Quercus petraea agg. The static modulus of rupture caused by L. sulphureus after 2, 4 and 6 months decreased in comparison with initial ones (100%) and reached 91.73, 75.17 and 63.25%. By using correlation analyses of Q. petraea agg. static modulus of rupture - ss (dependent variable) of fungi time influence (T-independent variable) strong correlation between variables was established, and regression equation is: ss= 151.514 ± 30,657 √ T The regression line obtained through data processing opened the possibility to prognosticate the changes of wood properties in certain time periods of the effect of the fungus under the unchanged external conditions, which is significant for practical purposes in terms of taking protective measures and wood usability.

scholarly journals 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 ◽  
2013 ◽  
Vol 67 (4) ◽  
pp. 447-454 ◽  
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.

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

Holzforschung ◽  
2009 ◽  
Vol 63 (3) ◽  
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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