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Recent global market disruptions, including the COVID-19 crisis, inflation, and oil crises, have highlighted the need for industries to reduce dependence on petrochemicals. However, the coating industry remains reliant on petrochemicals due to a lack of knowledge about local and sustainable alternatives. This study explored the potential of wood extractives as precursors for producing high-quality wood coatings. Terpenes were modified through acrylation, and bio-based latexes were synthesized from these modified terpenes. Analysis showed that all tested latexes had conversion levels above 88.5%. The bio-based films were characterized, and their transparency, measured by ultraviolet-visible spectroscopy, exceeded 80%. The good incorporation of bio-based monomers in the latex films was confirmed by thermogravimetric analysis and pyrolysis-gas chromatography-mass spectrometry. Comparative analysis between bio-based and conventional latexes showed equivalent results in particle size, molecular weight, glass transition temperature, and minimum film formation temperature. However, bio-based films exhibited lower hardness. The study suggests that using monomers derived from wood extractives offers a viable alternative to petrochemicals, utilizing abundant forest residues. This approach could address raw material shortages and help make the coatings industry more sustainable by reducing its reliance on petrochemicals.

Wooden structures are becoming increasingly popular in the construction world. However, these structures often rely on synthetic adhesives, raising concerns about the environmental risks associated with their chemical composition. In response to these concerns, this study aims to explore sustainable alternatives, particularly focusing on polyurethane adhesives that incorporate proteins from industrial byproducts. The investigation involved three protein sources: soybean meal, shrimp shells, and skim milk, modified under mild alkaline conditions to obtain protein concentrates. These concentrates were then incorporated into the adhesives at varying protein contents: 5%, 10%, and 15%. Additionally, two isocyanate systems were examined, one being petrochemical-based and the other a partially bio-based blend. Chemical, thermal, optical, and mechanical characterizations were conducted to evaluate the adhesive performance. This study demonstrates that the adhesives’ thermal properties remain unaffected by both the protein content and the isocyanate system. However, these factors influence the adhesive penetration into the wood substrate. Ultimately, the results suggest that higher protein content offers superior retention of mechanical strength in adhesives compared to the petrochemical reference when subjected to humid conditions. Overall, this research demonstrates the potential of proteins from industrial byproducts as sustainable adhesive allies, providing valuable insights into their interactions with different isocyanates.

Wooden structures are becoming increasingly popular in the construction world. However, these structures often rely on synthetic adhesives, raising concerns about the environmental risks associated with their chemical composition. In response to these concerns, this study aims to explore sustainable alternatives, particularly focusing on polyurethane adhesives that incorporate proteins from industrial byproducts. The investigation involved three protein sources: soybean meal, shrimp shells, and skim milk, modified under mild alkaline conditions to obtain protein concentrates. These concentrates were then incorporated into the adhesives at varying protein contents: 5%, 10%, and 15%. Additionally, two isocyanate systems were examined, one being petrochemical-based and the other a partially bio-based blend. Chemical, thermal, optical, and mechanical characterizations were conducted to evaluate the adhesive performance. This study demonstrates that the adhesives’ thermal properties remain unaffected by both the protein content and the isocyanate system. However, these factors influence the adhesive penetration into the wood substrate. Ultimately, the results suggest that higher protein content offers superior retention of mechanical strength in adhesives compared to the petrochemical reference when subjected to humid conditions. Overall, this research demonstrates the potential of proteins from industrial byproducts as sustainable adhesive allies, providing valuable insights into their interactions with different isocyanates.

Wood has a lower carbon footprint compared to many other materials used in construction. However, its hygroscopic nature poses significant challenges, including dimensional fluctuations in response to humidity shifts. Here we investigate a new treatment method mitigating swelling and shrinkage using dairy by-product named whey ultrafiltration permeate (mainly composed of lactose) and citric acid. Trembling aspen and black spruce samples were impregnated with ultrafiltration permeate and citric acid. Infrared and Raman spectroscopy were used to evaluate the esterification reaction and the location of the impregnates. We found increased ester bonds in the cell walls and the middle lamella (leaving the lumens empty), explaining the improved wood stability. Trembling aspen was more receptive to the treatment than black spruce, as shown by a higher weight gain (39 % vs. 13 %) and anti-swelling efficiency (54 % vs. 37 %). No leaching was observed during characterization of the treated wood. The modulus of elasticity and rupture, and the Brinell hardness were only slightly affected for both wood species. Upon combustion, esterified wood samples degraded at a lower temperature, but the stability of the residues was increased. This study highlights a promising use of ultrafiltration permeate in wood esterification.

Wood structures generally rely on synthetic adhesives for their strength and versatility. However, environmental concerns linked to the chemical composition of these adhesives have stimulated the search for more environmentally friendly adhesives. Researchers have explored replacing petroleum-based constituents with natural raw materials such as lignins, tannins, and proteins. Of these alternatives, proteins, being biological macromolecules, are recognized for their capacity to enhance adhesion to wood substrates. This study considered the development of protein-based adhesives derived from diverse sources, including soybean meal, microbrewery spent grains, shrimp shells, and skim milk powder. These raw materials were subjected to mild alkaline conditions to yield protein concentrates. The resulting adhesives were formulated at various protein content levels: 5%, 10%, 15%, and 20%. The study's findings showed that the incorporation of proteins into the polyurethane adhesive system not only can preserve but also augment adhesive performance. This enhancement encompasses deeper penetration into wood substrates and an overall improvement in mechanical strength. These results underscore the promise of proteins as a sustainable alternative to petroleum-based polyols in adhesive formulations.

Wood structures generally rely on synthetic adhesives for their strength and versatility. However, environmental concerns linked to the chemical composition of these adhesives have stimulated the search for more environmentally friendly adhesives. Researchers have explored replacing petroleum-based constituents with natural raw materials such as lignins, tannins, and proteins. Of these alternatives, proteins, being biological macromolecules, are recognized for their capacity to enhance adhesion to wood substrates. This study considered the development of protein-based adhesives derived from diverse sources, including soybean meal, microbrewery spent grains, shrimp shells, and skim milk powder. These raw materials were subjected to mild alkaline conditions to yield protein concentrates. The resulting adhesives were formulated at various protein content levels: 5%, 10%, 15%, and 20%. The study's findings showed that the incorporation of proteins into the polyurethane adhesive system not only can preserve but also augment adhesive performance. This enhancement encompasses deeper penetration into wood substrates and an overall improvement in mechanical strength. These results underscore the promise of proteins as a sustainable alternative to petroleum-based polyols in adhesive formulations.

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 at 5%), and differential vapor sorption (with a mass change of 2%wt at 0 parts per hundred of polyol versus 2.5%wt at 5% from 0% to 95% relative humidity). However, the required performances by the standards of polyurethane foam insulation material were always fulfilled regardless of the amount of cellulose filaments present.

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 at 5%), and differential vapor sorption (with a mass change of 2%wt at 0 parts per hundred of polyol versus 2.5%wt at 5% from 0% to 95% relative humidity). However, the required performances by the standards of polyurethane foam insulation material were always fulfilled regardless of the amount of cellulose filaments present.

Decorative wood panels containing pouches of bio-based phase changing materials (PCMs) were prepared. Three different PCM mixtures were used: a blend of capric and lauric acids as well as two commercial products, Puretemp®20 and Puretemp®23 (Puretemp). The panels consist of engraved Medium Density Fiberboard (MDF) filled with a plastic pouch filled with PCM. High density fiberboard (HDF) was used on top of the panels to enclose the PCM pouches. PCM mixtures were first tested by differential scanning calorimetry (DSC). Phase change temperature and total heat storage of the panels were measured for both fusion and solidification with a Dynamic Heat-Flow Meter Apparatus (DHFMA). DSC and DHFMA results were compared, allowing a better understanding of results gathered from these two techniques. DSC calibration has been revealed important when assessing PCMs. The panels present a phase change temperature and a latent heat storage suitable for buildings applications. The panel made with Puretemp®23 presented the highest energy, with 57.1 J g−1. Thermal cycling was conducted on the panels to investigate thermal reliability, which revealed small modifications of thermal properties for two products. For all cases, latent heat was found stable. Hygro-mechanical behavior of the panels was also evaluated as these where designed to be esthetic decorative panels. This study exposes the potential of a new type of wood-based panels loaded with PCM for thermal energy storage and brings overall knowledge about PCM products thermal characterization. Keywords: PCM, Wood, Biosourced, Fatty acids, DHFMA

Chemical impregnation of black spruce was conducted to enhance the wood embedment capacity. The formulation was made of 1,6 hexanediol diacrylate, trimethylpropane triacrylate, and a polyester acrylate oligomer. A second formulation, same as the first but with 1% wt of SiO2 nanoparticles, was selected to investigate the potential of nanoparticles and to improve the efficiency of the treatment. The wood embedment capacity was carried out by a dowel-bearing test, which was performed for the two treatments and for an untreated wood group. Both treatments showed an increase of strength of nearly 50% when compared to untreated samples. Micrograph views revealed that the impregnation solution penetrated into the wood only up to 100 μm. Hence, with low chemical consumption, the structural bearing capacity can be significantly increased.

Wood is a porous material that can be impregnated and have enhanced properties. Two species of hardwood, red oak (Quercus rubra L.) and sugar maple (Acer saccharum Marsh.), were impregnated in a reactor with a microencapsulated phase change material. The objective was to enhance the thermal mass of wood boards used as surface layers for engineered wood flooring manufacturing. Preliminary experiments were conducted on small samples in order to define suitable impregnation parameters, based on the Bethell cycle. Thin wood boards were impregnated with a microencapsulated phase change material dispersed into distilled water. Several cycles of pressure were applied. Heating storage of the impregnated wood boards was determined using a dynamic heat flow meter apparatus method. A latent heat storage of 7.6 J/g over 3 °C was measured for impregnated red oak samples. This corresponds to a heat storage enhancement of 77.0%. Sugar maple was found to be harder to impregnate and thus his thermal enhancement was lower. Impregnated samples were observed by reflective optical microscopy. Microcapsules were found mainly in the large vessels of red oak, forming aggregates. Pull-off tests were conducted on varnished samples to assess the influence of an impregnation on varnish adhesion and no significant influence was revealed. Engineered wood flooring manufactured with impregnated boards such as characterized in this study could store solar energy and thus improve buildings energy efficiency. Although wood is a material with a low-conductivity, the thermal exchange between the PCM and the building air could be good enough as the microcapsules are positioned in the surface layer. Furthermore, flooring is an area with frequent sunrays exposure. Such high thermal mass EWF could lead to energy savings and to an enhancement of occupant’s thermal comfort. This study aimed to characterize the potential of impregnation with MPCM of two wood species in order to make high thermal mass EWF.

The relatively low thermal mass of timber frame buildings is a limiting factor for their energy efficiency and for the thermal comfort. The aim of this study is to assess the performance of wood-based wallboards integrated with PCM (Phase Change Materials) in a cold climate (Québec, Canada), from the heating season to the summer. Two timber-frame test huts, of 2 × 2.5 × 3 m, were built following the National Building Code of Canada and placed in the LAVAL University Campus. The first hut was equipped with wood-based panels integrated with the commercial bio-based PCM Puretemp®23 with a 23 °C melting point. The second hut was equipped with standard interior wood panels. Large double glaze windows were installed facing south. Dry indoor air temperatures were recorded for both huts and for the heating season, heating consumptions were monitored. The behaviour of the two huts was compared and PCM panels efficiency was evaluated over several seasons. A reduction of heating consumption was observed for cold months. For the heating season, panels were found to be more efficient as the months were getting milder. By gathering solar energy during the day, they allowed to reduce the test-hut heating consumption, by a maximum of 41% in May. In summer, the PCM panels had a positive impact in order to reduce the hut overheating. However their efficiency was found limited by a poor ability of discharge during the night. The solidification of the PCM was often impossible to achieve due to unsuitable night conditions. The results presented in this study will improve the knowledge concerning wood/PCM composites performance and concerning PCMs issues in cold climates. This study exposes the potential of wood-based panels integrated with PCM to achieve winter energy savings and enhance the summer thermal comfort of a timber-frame building, for a cold Canadian climate.

Three hybrid systems were compared to a solvent-based low-VOC system. The goal of the project was to determine if the hybrid systems met the requirements of the kitchen cabinet and furniture industries. Adhesion of each system to the substrate was first evaluated, and significant differences were recorded. Subsequently, resistance to heat and moisture was evaluated using hot box and hot and cold check tests. These tests indicated that the experimental systems generally performed relatively well in terms of thermal resistance, but the appearance of those prepared from solvent-borne sealers and lacquers were less stable. The chemical resistance of these systems was also studied. The ability of the finish to withstand the effects of substances typically found in a kitchen was tested, as was their resistance to detergents and water. All the systems performed very well in vertical testing. Volatile organic compound emissions were finally measured after conditioning times of 3 and 21 days. These tests showed that the different systems behaved quite differently. The systems prepared with solvent-borne sealers and lacquers produced a high level of VOCs at the beginning of the test, with a rapid decrease thereafter, while the opposite was observed in systems based on water-borne sealers and lacquers.

Wood material is a good reservoir for biogenic carbon storage. The use of wood material for outdoor products such as siding in the building construction sector presents limits. These limits are bound to the nature of wood material (hygroscopic property and anatomical structure). They are responsible for the dimensional variation associated with moisture content variations. Fungal attacks and coating layers adhesion on wood surface, are other problems. This research investigated the feasibility of impregnation with environmentally friendly chemicals, i.e., a citric acid-glycerol mixture (CA-G). The anti-swelling efficiency (ASE), hardness, biodegradation, and coating adhesion tests were performed on softwood specimens. ASE results were up to 53%. The equilibrium moisture content of the treated specimens was less than half of the untreated ones. FTIR spectroscopy showed bands at 1720 to 1750 cm-1, indicating the presence of ester bonds, and scanning electron microscopy images confirmed the polymerization and condensation of treatment solution inside the wood structure. Hardness and decay resistance were increased; however, treatment reduces coating adhesion. In conclusion, CA-G represents a promising eco-responsible solution for improving the technical performance of outdoor wood products.

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.