European Journal of Wood and Wood Products, Jan 4, 2022
Wood products that are used in indoor environments can be exposed during their use to UV–vis ligh... more Wood products that are used in indoor environments can be exposed during their use to UV–vis light through window glass. Exposure of wood products to UV–vis light can cause discoloration due to changes in structures of wood components such as extractives and lignin. In this study, the color stability during artificial aging of white oak wood stained with iron (III) and nickel (II) salts with and without a standard UV-curable finishing system was evaluated for indoor applications. To do so, color measurements were performed at different stages of the aging process. Fourier transform mid and near infrared and X-ray photoelectron spectroscopies were used to compare the rate of degradation of wood and to analyze the metals on wood’s surface. The results of this study showed that the addition of metal ions to wood had a photoprotective effect on lignin’s degradation during the first stages of artificial aging. Higher protection of lignin was shown for nickel (II) acetate-stained wood at 4% w/v. During the first 24 h, Δa* and Δb* increased for all uncoated samples, which indicates that the color of wood surface was modified to redder and yellower hues. For wood stained with iron (III) sulfate, the color of wood samples shifted from blue to dark brown. The addition of a standard UV-curable finishing system decreased the color changes for all samples. For nickel-stained wood, color changes were not perceptible after the first 24 h of aging with a UV-curable finishing system in contrary to iron-stained wood.
Wood used outdoor is subjected to different sources of degradation and should be protected proper... more Wood used outdoor is subjected to different sources of degradation and should be protected properly. In this study, acrylic resins were added to a wood impregnation system using amine oxides and propiconazole, an organic fungicide, to create a two-part wood protection preservation treatment. Since amine oxides can diffuse readily into wood, this treatment protected both the surface and inner structure of the treated wood following a simple dipping. Many aspects of the treatment were studied: the adhesion of the acrylic coatings, their permeability to water, and the impregnation depth of the propiconazole. In each case, a particular attention was accorded to the interactions between the resins and the impregnation system. Adhesion and permeability tests were coupled with an artificial aging process simulating severely wet conditions. Amine oxides reduced the adhesion of the coatings but did not impair their aging properties. Because of their hydrophilic nature, they also increased the permeability to liquid water, although they did not affect the air moisture permeability. The penetration of the propiconazole, estimated with a dye, decreased with the resin. Overall, the two parts of the treatment lightly impaired each other, but the practical aspect of this treatment may overcome these disadvantages.
Wood is a renewable material widely used in many applications due to its unique properties and di... more Wood is a renewable material widely used in many applications due to its unique properties and distinctive look. However, as wood is organically constituted, it is slowly destroyed by the long-term impact of oxygen, UV radiations, water, and biological attacks (Mahltig et al., 2008). Therefore, protective treatments are necessary to improve the mechanical, thermal, and chemical properties of wood. In order to improve the mechanical properties of sugar maple (Acer saccharum Marsh.), as this species is widely used in the wood products industry, samples of sugar maple were impregnated with sols of metal oxides (AlO(OH), SiO 2 , and ZrO 2). The weight gain and two different techniques of microscopy were used to evaluate the efficiency of the impregnation in the wood samples. The mechanical properties were evaluated using hardness test, scratch test, and impact test. It was shown that the maple samples impregnated with ZrO 2 led to the greatest improvement of the mechanical properties.
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
One of the major issues in the wood industry is the durability of clear coatings. The addition of... more One of the major issues in the wood industry is the durability of clear coatings. The addition of organic ultraviolet absorbers (UVAs) improves coating resistance by the absorption and conversion of UV radiation into harmless heat. Organic UVAs are, however, easily degraded by free radicals produced by photodegradation inside the polymer matrix and are prone to migration in the coating. In this study, commercial UVAs and hindered amine light stabilizers (HALS) entrapped into poly(methyl methacrylate) (PMMA) microspheres and CaCO 3 templates coated with UV-responsive polymers were added into clear acrylic water-based coating formulation. Artificial accelerated weathering experiments were performed on each formulation. Raman spectroscopy mapping was performed to visualize the concentration and distribution of UVAs and HALS. This study also presents a comparison of the mechanical properties of coatings obtained by dynamic mechanical analysis. Results showed that coating mechanical properties were improved when using encapsulated UVAs and HALS inside PMMA microspheres. The color change of the wood and coating system was minimized and the production of photo-oxidation compounds in the binder was also limited.
UV-curable coatings possess numerous advantages, including high production rate, low environmenta... more UV-curable coatings possess numerous advantages, including high production rate, low environmental impact, and customizability, making them highly appealing for a wide range of applications. However, one of the greatest challenges in UV-curable coating is achieving an optimal low-gloss surface by adding matting agents to the coating formulation. Therefore, it is essential to find a suitable matting agent type and an efficient roughness creation method to tailor the surface gloss and generate a controlled low-gloss surface. In this study, modified magnetic particles were added to the coating formulation as matting agents, and the UV curing process was conducted under a magnetic field of 10 to 100 mT. The combined effect of adding magnetic particles and magnetic field during UV curing on the coatings’ surface gloss was investigated. The impact of modification, dispersion, and concentration of magnetic particles and the effect of magnetic field force on the final surface gloss and roug...
Cellulose is a biopolymer that has broad potential applications including in building insulation,... more Cellulose is a biopolymer that has broad potential applications including in building insulation, and it was studied for its potential as a filler material. A closed-cell polyurethane foam insulation formulation was developed, and cellulose filaments (CFs) were introduced at varying percentages. The viscosity and morphology of the formulations were studied, as were different foam properties, such as water vapor permeability, reaction kinetics, density, porosity, thermal conductivity, and compressive strength foams as a function of cellulose filaments content. A commercial foam was also tested as a reference. The cellulose filaments impacted the formulations’ viscosity, and all the properties of the resulting insulating material. For example, samples containing 5% of cellulose filaments were found to perform differently than samples containing 0%, 1% and 2.5% mainly due to agglomerate formation, which impacted cell size (about 0.1 mm2 at 0%, 1% and 2.5% versus a mean of over 0.4 mm2 ...
Translucent coatings applied to wood that is used for exterior applications often fail because of... more Translucent coatings applied to wood that is used for exterior applications often fail because of photodegradation and colonisation by black-stain fungi. This paper reports the effect of silver nanoparticles on the black-stain resistance of acrylic latex coatings. Acrylic latexes that contained various concentrations of silver nanoparticles were mixed with a commercial acrylic resin. The formulations were then applied to red pine (Pinus resinosa) sapwood, which was later evaluated for fungal resistance to Aureobasidium pullulans, Sclerophoma pityophila, and Eppicoccum nigrum. Latexes with silver nanoparticle concentrations as low as 0.03% (total coating formulation weight) were able to limit S. pityophila and E. nigrum growth, while higher concentrations were needed to limit the growth of A. pullulans. The influences of silver nanoparticles on the optical properties of the coating (i.e., colour, opacity, and gloss) were evaluated. It was demonstrated that the addition of silver nano...
The application of a flame retardant coating is an effective solution to enhance the fire retarda... more The application of a flame retardant coating is an effective solution to enhance the fire retardancy of wood flooring. However, finding the right balance between reducing the flame propagation and good overall coating properties while conserving wood appearance is complex. In order to answer this complex problem, transparent ultraviolet (UV)-curable flame retardant wood coatings were prepared from an acrylate oligomer, an acrylate monomer, and the addition of the tri(acryloyloxyethyl) phosphate (TAEP), a phosphorus-based monomer, at different concentrations in the formulation. The coatings’ photopolymerisation, optical transparency, hardness, water sorption and thermal stability were assessed. The fire behaviour and the adhesion of the coatings applied on the yellow birch panels were evaluated, respectively, using the cone calorimeter and pull-off tests. Scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) analyses were performed on the collected burnt residue...
Wood is a biosourced material with unique aesthetic features due to its anatomy and chemical comp... more Wood is a biosourced material with unique aesthetic features due to its anatomy and chemical composition. White oak wood surface color can be modified with the use of iron salts, which react with wood phenolic extractives, present as free molecules in wood porous structure. The impact of modifying wood surface color with iron salts on the final appearance of wood, including its color, grain contrast and surface roughness, was evaluated in this study. Results showed that following the application of iron (III) sulphate aqueous solutions on white oak wood surface, its roughness increased, which is due to grain raising after wetting of wood surface. The color modification of wood surface with iron (III) sulphate aqueous solutions was compared with a non-reactive water based blue stain. The contrast associated to wood grain that was expressed by the standard deviation of luminance values in wood images, also increased after application of the iron (III) sulphate aqueous solution on whit...
Wood is an environmentally friendly material for the construction of buildings, and it possesses ... more Wood is an environmentally friendly material for the construction of buildings, and it possesses great physical and mechanical properties. However, under certain circumstances, it needs to be protected from degradation. This can be achieved either by proper design or treatment. In this study, eastern white pine (Pinus strobus L.) and white spruce (Picea glauca (Moench) Voss) were impregnated with propiconazole and 3-iodo-2-propynyl butylcarbamate, which are two organic fungicides. Unlike most impregnation techniques, no pressure treatment was needed. Instead, an aqueous buffered amine oxide system was used to allow the fungicides to diffuse rapidly into the wood. Many combinations of fungicides and amine oxides, as well as different diffusion times were tested to study the effect of the treatment on the dimensional stability and resistance to decay fungi. It was found that only the amine oxide affected the dimensional stability of the treated wood, with anti-swelling and anti-shrink...
Wood products that are used in indoor environments can be exposed during their use to UV–vis ligh... more Wood products that are used in indoor environments can be exposed during their use to UV–vis light through window glass. Exposure of wood products to UV–vis light can cause discoloration due to changes in structures of wood components such as extractives and lignin. In this study, the color stability during artificial aging of white oak wood stained with iron (III) and nickel (II) salts with and without a standard UV-curable finishing system was evaluated for indoor applications. To do so, color measurements were performed at different stages of the aging process. Fourier transform mid and near infrared and X-ray photoelectron spectroscopies were used to compare the rate of degradation of wood and to analyze the metals on wood’s surface. The results of this study showed that the addition of metal ions to wood had a photoprotective effect on lignin’s degradation during the first stages of artificial aging. Higher protection of lignin was shown for nickel (II) acetate-stained wood at 4% w/v. During the first 24 h, Δa* and Δb* increased for all uncoated samples, which indicates that the color of wood surface was modified to redder and yellower hues. For wood stained with iron (III) sulfate, the color of wood samples shifted from blue to dark brown. The addition of a standard UV-curable finishing system decreased the color changes for all samples. For nickel-stained wood, color changes were not perceptible after the first 24 h of aging with a UV-curable finishing system in contrary to iron-stained wood.
In a high‐rise building, due to the risk of flame spread and strict regulations associated, wood ... more In a high‐rise building, due to the risk of flame spread and strict regulations associated, wood use is limited for interior finishes. This study aimed to evaluate the effect of a thin organosilicon layer (∼500 nm) prepared by atmospheric pressure plasma on the fire behavior of a wood substrate. The coating was deposited from hexamethyldisiloxane in argon on both untreated wood and wood with a preparatory coating of primer. The primer reduces the presence of cracks in the plasma layer and ensures more homogenous coverage of the substrates. Finally, the flame retardancy analysis highlights an improvement in fire behavior only when the primer is used. Our study suggests that plasma thin deposition has a synergic effect with primer to fireproof wood.
the polymer and wood macromolecules were observed by scanning electron microscopy and interpreted... more the polymer and wood macromolecules were observed by scanning electron microscopy and interpreted as evidence of chemical bonds at the wood cells. When prepared using a catalyst, the polymer was intimately incorporated into wood structure significantly improving the substrate dimensional stability. Enhanced stability makes this approach of particular interest for exterior wood products especially as a green renewable option for the wood industry.
To improve technical performance of wood siding, treatment with maleic anhydride was applied. The... more To improve technical performance of wood siding, treatment with maleic anhydride was applied. The effects on technical performance of drying time and esterification temperature parameters were analyzed. Wood samples of lodgepole pine and white pine were treated and tested. Results indicated that treatment improves technical performance of wood (dimensional stability, fungal degradation resistance, and accelerated aging). FTIR spectroscopy analysis showed spectra with peaks at 1750 to 1730 cm-1. These correspond to ester bonds formed between wood hydroxyl groups and MA carboxylic acid groups. SEM images indicate that the MA quantity in wood cavities was increased with decreasing esterification temperature. Weight percent gain (WPG) increased with decreasing time and temperature of esterification. Artificial aging and fungal degradation performances were monitored using FTIR analysis. Esterification temperature had no important effect on fungal degradation. Weight loss after fungal exposure of treated samples was not only due to fungal action but also due to evaporation of MA during the drying step. Regarding artificial aging, degradation of wood components and ester bonds were less for samples esterified at 180 °C than those esterified at 160 °C or 140 °C.
European Journal of Wood and Wood Products, Jan 4, 2022
Wood products that are used in indoor environments can be exposed during their use to UV–vis ligh... more Wood products that are used in indoor environments can be exposed during their use to UV–vis light through window glass. Exposure of wood products to UV–vis light can cause discoloration due to changes in structures of wood components such as extractives and lignin. In this study, the color stability during artificial aging of white oak wood stained with iron (III) and nickel (II) salts with and without a standard UV-curable finishing system was evaluated for indoor applications. To do so, color measurements were performed at different stages of the aging process. Fourier transform mid and near infrared and X-ray photoelectron spectroscopies were used to compare the rate of degradation of wood and to analyze the metals on wood’s surface. The results of this study showed that the addition of metal ions to wood had a photoprotective effect on lignin’s degradation during the first stages of artificial aging. Higher protection of lignin was shown for nickel (II) acetate-stained wood at 4% w/v. During the first 24 h, Δa* and Δb* increased for all uncoated samples, which indicates that the color of wood surface was modified to redder and yellower hues. For wood stained with iron (III) sulfate, the color of wood samples shifted from blue to dark brown. The addition of a standard UV-curable finishing system decreased the color changes for all samples. For nickel-stained wood, color changes were not perceptible after the first 24 h of aging with a UV-curable finishing system in contrary to iron-stained wood.
Wood used outdoor is subjected to different sources of degradation and should be protected proper... more Wood used outdoor is subjected to different sources of degradation and should be protected properly. In this study, acrylic resins were added to a wood impregnation system using amine oxides and propiconazole, an organic fungicide, to create a two-part wood protection preservation treatment. Since amine oxides can diffuse readily into wood, this treatment protected both the surface and inner structure of the treated wood following a simple dipping. Many aspects of the treatment were studied: the adhesion of the acrylic coatings, their permeability to water, and the impregnation depth of the propiconazole. In each case, a particular attention was accorded to the interactions between the resins and the impregnation system. Adhesion and permeability tests were coupled with an artificial aging process simulating severely wet conditions. Amine oxides reduced the adhesion of the coatings but did not impair their aging properties. Because of their hydrophilic nature, they also increased the permeability to liquid water, although they did not affect the air moisture permeability. The penetration of the propiconazole, estimated with a dye, decreased with the resin. Overall, the two parts of the treatment lightly impaired each other, but the practical aspect of this treatment may overcome these disadvantages.
Wood is a renewable material widely used in many applications due to its unique properties and di... more Wood is a renewable material widely used in many applications due to its unique properties and distinctive look. However, as wood is organically constituted, it is slowly destroyed by the long-term impact of oxygen, UV radiations, water, and biological attacks (Mahltig et al., 2008). Therefore, protective treatments are necessary to improve the mechanical, thermal, and chemical properties of wood. In order to improve the mechanical properties of sugar maple (Acer saccharum Marsh.), as this species is widely used in the wood products industry, samples of sugar maple were impregnated with sols of metal oxides (AlO(OH), SiO 2 , and ZrO 2). The weight gain and two different techniques of microscopy were used to evaluate the efficiency of the impregnation in the wood samples. The mechanical properties were evaluated using hardness test, scratch test, and impact test. It was shown that the maple samples impregnated with ZrO 2 led to the greatest improvement of the mechanical properties.
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
One of the major issues in the wood industry is the durability of clear coatings. The addition of... more One of the major issues in the wood industry is the durability of clear coatings. The addition of organic ultraviolet absorbers (UVAs) improves coating resistance by the absorption and conversion of UV radiation into harmless heat. Organic UVAs are, however, easily degraded by free radicals produced by photodegradation inside the polymer matrix and are prone to migration in the coating. In this study, commercial UVAs and hindered amine light stabilizers (HALS) entrapped into poly(methyl methacrylate) (PMMA) microspheres and CaCO 3 templates coated with UV-responsive polymers were added into clear acrylic water-based coating formulation. Artificial accelerated weathering experiments were performed on each formulation. Raman spectroscopy mapping was performed to visualize the concentration and distribution of UVAs and HALS. This study also presents a comparison of the mechanical properties of coatings obtained by dynamic mechanical analysis. Results showed that coating mechanical properties were improved when using encapsulated UVAs and HALS inside PMMA microspheres. The color change of the wood and coating system was minimized and the production of photo-oxidation compounds in the binder was also limited.
UV-curable coatings possess numerous advantages, including high production rate, low environmenta... more UV-curable coatings possess numerous advantages, including high production rate, low environmental impact, and customizability, making them highly appealing for a wide range of applications. However, one of the greatest challenges in UV-curable coating is achieving an optimal low-gloss surface by adding matting agents to the coating formulation. Therefore, it is essential to find a suitable matting agent type and an efficient roughness creation method to tailor the surface gloss and generate a controlled low-gloss surface. In this study, modified magnetic particles were added to the coating formulation as matting agents, and the UV curing process was conducted under a magnetic field of 10 to 100 mT. The combined effect of adding magnetic particles and magnetic field during UV curing on the coatings’ surface gloss was investigated. The impact of modification, dispersion, and concentration of magnetic particles and the effect of magnetic field force on the final surface gloss and roug...
Cellulose is a biopolymer that has broad potential applications including in building insulation,... more Cellulose is a biopolymer that has broad potential applications including in building insulation, and it was studied for its potential as a filler material. A closed-cell polyurethane foam insulation formulation was developed, and cellulose filaments (CFs) were introduced at varying percentages. The viscosity and morphology of the formulations were studied, as were different foam properties, such as water vapor permeability, reaction kinetics, density, porosity, thermal conductivity, and compressive strength foams as a function of cellulose filaments content. A commercial foam was also tested as a reference. The cellulose filaments impacted the formulations’ viscosity, and all the properties of the resulting insulating material. For example, samples containing 5% of cellulose filaments were found to perform differently than samples containing 0%, 1% and 2.5% mainly due to agglomerate formation, which impacted cell size (about 0.1 mm2 at 0%, 1% and 2.5% versus a mean of over 0.4 mm2 ...
Translucent coatings applied to wood that is used for exterior applications often fail because of... more Translucent coatings applied to wood that is used for exterior applications often fail because of photodegradation and colonisation by black-stain fungi. This paper reports the effect of silver nanoparticles on the black-stain resistance of acrylic latex coatings. Acrylic latexes that contained various concentrations of silver nanoparticles were mixed with a commercial acrylic resin. The formulations were then applied to red pine (Pinus resinosa) sapwood, which was later evaluated for fungal resistance to Aureobasidium pullulans, Sclerophoma pityophila, and Eppicoccum nigrum. Latexes with silver nanoparticle concentrations as low as 0.03% (total coating formulation weight) were able to limit S. pityophila and E. nigrum growth, while higher concentrations were needed to limit the growth of A. pullulans. The influences of silver nanoparticles on the optical properties of the coating (i.e., colour, opacity, and gloss) were evaluated. It was demonstrated that the addition of silver nano...
The application of a flame retardant coating is an effective solution to enhance the fire retarda... more The application of a flame retardant coating is an effective solution to enhance the fire retardancy of wood flooring. However, finding the right balance between reducing the flame propagation and good overall coating properties while conserving wood appearance is complex. In order to answer this complex problem, transparent ultraviolet (UV)-curable flame retardant wood coatings were prepared from an acrylate oligomer, an acrylate monomer, and the addition of the tri(acryloyloxyethyl) phosphate (TAEP), a phosphorus-based monomer, at different concentrations in the formulation. The coatings’ photopolymerisation, optical transparency, hardness, water sorption and thermal stability were assessed. The fire behaviour and the adhesion of the coatings applied on the yellow birch panels were evaluated, respectively, using the cone calorimeter and pull-off tests. Scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) analyses were performed on the collected burnt residue...
Wood is a biosourced material with unique aesthetic features due to its anatomy and chemical comp... more Wood is a biosourced material with unique aesthetic features due to its anatomy and chemical composition. White oak wood surface color can be modified with the use of iron salts, which react with wood phenolic extractives, present as free molecules in wood porous structure. The impact of modifying wood surface color with iron salts on the final appearance of wood, including its color, grain contrast and surface roughness, was evaluated in this study. Results showed that following the application of iron (III) sulphate aqueous solutions on white oak wood surface, its roughness increased, which is due to grain raising after wetting of wood surface. The color modification of wood surface with iron (III) sulphate aqueous solutions was compared with a non-reactive water based blue stain. The contrast associated to wood grain that was expressed by the standard deviation of luminance values in wood images, also increased after application of the iron (III) sulphate aqueous solution on whit...
Wood is an environmentally friendly material for the construction of buildings, and it possesses ... more Wood is an environmentally friendly material for the construction of buildings, and it possesses great physical and mechanical properties. However, under certain circumstances, it needs to be protected from degradation. This can be achieved either by proper design or treatment. In this study, eastern white pine (Pinus strobus L.) and white spruce (Picea glauca (Moench) Voss) were impregnated with propiconazole and 3-iodo-2-propynyl butylcarbamate, which are two organic fungicides. Unlike most impregnation techniques, no pressure treatment was needed. Instead, an aqueous buffered amine oxide system was used to allow the fungicides to diffuse rapidly into the wood. Many combinations of fungicides and amine oxides, as well as different diffusion times were tested to study the effect of the treatment on the dimensional stability and resistance to decay fungi. It was found that only the amine oxide affected the dimensional stability of the treated wood, with anti-swelling and anti-shrink...
Wood products that are used in indoor environments can be exposed during their use to UV–vis ligh... more Wood products that are used in indoor environments can be exposed during their use to UV–vis light through window glass. Exposure of wood products to UV–vis light can cause discoloration due to changes in structures of wood components such as extractives and lignin. In this study, the color stability during artificial aging of white oak wood stained with iron (III) and nickel (II) salts with and without a standard UV-curable finishing system was evaluated for indoor applications. To do so, color measurements were performed at different stages of the aging process. Fourier transform mid and near infrared and X-ray photoelectron spectroscopies were used to compare the rate of degradation of wood and to analyze the metals on wood’s surface. The results of this study showed that the addition of metal ions to wood had a photoprotective effect on lignin’s degradation during the first stages of artificial aging. Higher protection of lignin was shown for nickel (II) acetate-stained wood at 4% w/v. During the first 24 h, Δa* and Δb* increased for all uncoated samples, which indicates that the color of wood surface was modified to redder and yellower hues. For wood stained with iron (III) sulfate, the color of wood samples shifted from blue to dark brown. The addition of a standard UV-curable finishing system decreased the color changes for all samples. For nickel-stained wood, color changes were not perceptible after the first 24 h of aging with a UV-curable finishing system in contrary to iron-stained wood.
In a high‐rise building, due to the risk of flame spread and strict regulations associated, wood ... more In a high‐rise building, due to the risk of flame spread and strict regulations associated, wood use is limited for interior finishes. This study aimed to evaluate the effect of a thin organosilicon layer (∼500 nm) prepared by atmospheric pressure plasma on the fire behavior of a wood substrate. The coating was deposited from hexamethyldisiloxane in argon on both untreated wood and wood with a preparatory coating of primer. The primer reduces the presence of cracks in the plasma layer and ensures more homogenous coverage of the substrates. Finally, the flame retardancy analysis highlights an improvement in fire behavior only when the primer is used. Our study suggests that plasma thin deposition has a synergic effect with primer to fireproof wood.
the polymer and wood macromolecules were observed by scanning electron microscopy and interpreted... more the polymer and wood macromolecules were observed by scanning electron microscopy and interpreted as evidence of chemical bonds at the wood cells. When prepared using a catalyst, the polymer was intimately incorporated into wood structure significantly improving the substrate dimensional stability. Enhanced stability makes this approach of particular interest for exterior wood products especially as a green renewable option for the wood industry.
To improve technical performance of wood siding, treatment with maleic anhydride was applied. The... more To improve technical performance of wood siding, treatment with maleic anhydride was applied. The effects on technical performance of drying time and esterification temperature parameters were analyzed. Wood samples of lodgepole pine and white pine were treated and tested. Results indicated that treatment improves technical performance of wood (dimensional stability, fungal degradation resistance, and accelerated aging). FTIR spectroscopy analysis showed spectra with peaks at 1750 to 1730 cm-1. These correspond to ester bonds formed between wood hydroxyl groups and MA carboxylic acid groups. SEM images indicate that the MA quantity in wood cavities was increased with decreasing esterification temperature. Weight percent gain (WPG) increased with decreasing time and temperature of esterification. Artificial aging and fungal degradation performances were monitored using FTIR analysis. Esterification temperature had no important effect on fungal degradation. Weight loss after fungal exposure of treated samples was not only due to fungal action but also due to evaporation of MA during the drying step. Regarding artificial aging, degradation of wood components and ester bonds were less for samples esterified at 180 °C than those esterified at 160 °C or 140 °C.
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