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European Journal of Wood and Wood Products
Journal Prestige (SJR): 0.624  Citation Impact (citeScore): 1 Number of Followers: 3  Hybrid journal (It can contain Open Access articles)ISSN (Print) 0018-3768 - ISSN (Online) 1436-736X Published by Springer-Verlag  [2468 journals]
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- Investigations for increasing the 3D-forming potential of high-density
fiberboards-
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Abstract: Abstract The trend in modern interior design leans towards curved and shaped surfaces. This cannot be achieved with flat materials without additional effort. Materials from renewable resources, such as wood-based materials, are material- and energy-intensively processed to enable larger deformations. Therefore, this study deals with methods to increase the deformation potential of adhesive-free, high-density fiberboards. One method is plasticizing in a saturated steam atmosphere, which is well known from the bending of solid wood. The second is the application of a special kerf pattern that geometrically increases the deformability. The combination of both methods was also investigated. Uniaxial tensile tests were performed to evaluate the deformation potential of the methods used. The strain along and transverse to the tensile direction, as well as the modulus of elasticity and Poisson’s ratio, were determined as results. All the methods investigated lead to an increase in the maximum strain along the tensile load: steaming by a factor of 2, kerf patterning by a factor of 4, and the combination by a factor of 10 as compared to solid fiberboard. The application of the kerf pattern causes an auxetic material behavior with a negative Poisson’s ratio. The combination of both methods reduces the modulus of elasticity by a factor of more than 100. Overall, the investigated methods are suitable for increasing the deformation potential of fiberboards with regard to the forming of 3D-shaped surfaces.
PubDate: 2024-08-09
DOI: 10.1007/s00107-024-02115-w
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- Impact of coppice and high stem management on Eucalyptus wood quality
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Abstract: Abstract Coppicing, a well-studied forestry management system, offers significant productivity and economic benefits to plantations. This study aimed to assess the growth and wood quality differences in ten Eucalyptus genotypes, for example, E. grandis x E. urophylla (G3, G4, G5, G6, G8, G10, and G13), E. urophylla (G12), E. saligna (G14), and E. grandis x E. camaldulensis (G16) at three years old under high stem and coppice regimes, considering stem quantity variations. Six trees per clone were sampled in both regimes, with coppice trees having either one or two stems. Various wood and bark properties, including basic density, biomass estimation, pith eccentricity, and heartwood percentage were evaluated. Clone G12 showed the highest increment average volume among the treatments, while clones G14 and G16 had the lowest performances across all management regimes. Under high stem and coppice management, the clones show basic wood density ranging from 485 to 393 kg m-3 and 482 to 405 kg m-3, respectively. Generally, trees grown under the coppice regime produced more heartwood. Under the two-stem coppice regime, 90% of the clones showed greater pith eccentricity in their basal discs. Pith eccentricity varied significantly among clones, with coppice (especially with two stems) showing greater eccentricity compared to high stem management. Overall, wood properties did not significantly differ between high stem and coppice management for the evaluated Eucalyptus clones at three years old, except for pith eccentricity, which favored coppice with two stems. This study highlights the potential benefits of coppicing for specific wood quality traits in Eucalyptus plantations.
PubDate: 2024-08-08
DOI: 10.1007/s00107-024-02125-8
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- Evaluation of wood chips terminal velocity and some morphological
properties in a wind tunnel experiment-
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Abstract: Abstract The removal of wood dust and chips from the work area is also important for occupational health safety regulation and to avoid the risk of fire and dust explosion. Knowledge of the terminal velocity is an important condition for the effective and economical operation of commonly used wood dust-chip extraction systems. While the largest particles are important from the point of view of the operation of the extraction system, knowledge of the terminal velocity of small particles (under 1 mm) is desirable from the point of view of separation and occupational health safety. New measuring and calculation method is developed in order to determine the terminal velocity of wood particles. We built an experimental device to measure the terminal velocity of wood dust-chip particles, and using the experimental results, we modified the calculated terminal velocity based on the modified equivalent particle density (100–130 kg/m3) in the 1–150 μm size range. The terminal velocity of wood particles under 150 μm more and more deviates from the theoretical values. As a result of mechanical processing, the resulting wood particles’ shape is in most cases flat. The average thickness of the wood particles is mainly determined by the sawing parameters. The flat shape of particles increases the specific surface area in a certain extent depending on the distribution parameters.
PubDate: 2024-08-05
DOI: 10.1007/s00107-024-02123-w
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- Experimental investigations on the behaviour of structural-sized wood-CFRP
composite beams in local fire-
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Abstract: Abstract The study involved combustion of 24 structural-sized beams under three-point bending subjected to substantial loading prior to ignition, reaching 90% of characteristic load-carrying capacity. A localised fire exposure zone was established proximal to the region experiencing the highest bending moment. The specimens were categorised into two groups: the first consisted of tituted by glued-laminated timber (B), and the second comprised wood-CFRP (carbon fibre reinforced polymer) composite (BW). Initial measurements encompassed pre-ignition static deflection and load. Subsequently, the specimens underwent controlled combustion, during which parameters including burning duration and deflection up to failure, were documented. Following cooling with sand, two cross-sectional slices were extracted from each fractured beam, enabling to find vector-based contours of the remaining cross-section. The charring rate and the approximate heat flux density for each test were determined, enabling a direct comparison of the results. A statistically significant number of specimens was examined, facilitating a comparative analysis between reinforced and unreinforced beams concerning failure time and form. Incorporating CFRP tapes among wooden constituents was found to increase the fire resistance of the structure, however, the thickness of the wooden material enveloping the CFRP composite emerges as a pivotal determinant. This issue needs thorough testing under standard fire in the future. Nevertheless, the fact is that adding CFRP tapes engenders a distinct form of beam collapse, transitioning from instantaneous cracking in B-beams to ductile failure in BW-beams.
PubDate: 2024-08-05
DOI: 10.1007/s00107-024-02130-x
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- Novel thermally regenerated flexible cellulose-based films
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Abstract: Abstract In this work, cellulose powder obtained by acid hydrolysis of industrial Eucalyptus kraft pulp was dissolved in NaOH/Urea/H2O system (7/12/81 wt%) in a concentration of 6% (w/v). Cellulose films were prepared by spreading the dissolved cellulose over glass plates, followed by thermal regeneration – a novel approach reported here for the first time. To obtain final flexible films, plasticization was carried out by immersion in aqueous glycerol solutions of various concentrations (10 to 70 wt%) and hot-pressing (at 0.1 MPa and 105 ºC) was used to dry and compress the cellulose films. The resulting films were characterized by Attenuated Total Reflectance Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, X-ray diffraction, contact angle measurements, transparency analysis, and gas permeabilities (oxygen and water vapor). Highly flexible films containing up to 50 wt% of glycerol were successfully obtained, exhibiting no glycerol release upon manual handling. Overall, the produced films demonstrated dense and compact structure, good transparency, flexibility and malleability, and very low oxygen permeability.
PubDate: 2024-08-05
DOI: 10.1007/s00107-024-02126-7
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- Mechanical and thermal analysis of basalt grid reinforced particleboards
containing flame retardants-
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Abstract: Abstract Flame retardants and other additives can reduce the performance of adhesives used to produce wood-based panels such as particleboards (PB). Basalt reinforcement was evaluated to compensate for the loss of bending strength to allow the panels to be used in the construction sector. A basalt grid with a grammage of 200 g m−2 was used to reinforce PB containing 15 m% nitrogen-phosphate based flame retardant. The modulus of rupture (MOR) and modulus of elasticity (MOE) of the reinforced panels were higher (69% and 24%, respectively) than those of corresponding reference panels. The thermal analysis revealed that the addition of the flame retardant could result in the PB being upgraded to Euroclass B with a reduced crack formation, as identified via 3D-microscopy. Consequently, the use of basalt grid as a reinforcement material could be a way to reinforce panels that contain strength-reducing additives.
PubDate: 2024-08-02
DOI: 10.1007/s00107-024-02127-6
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- Study on surface creation and wettability of bamboo through abrasive belt
sanding-
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Abstract: Abstract In manufacturing bamboo products, sanding is an important method to make surface modification. In this study, mechanical sanding experiments were carried out to investigate the resultant surface creation and wettability. Electrostatic sand-planting abrasive belts with meshes of P60, P80, P120 were selected as abrasive tools. Dimensional bamboo strips were used to prepare workpieces with wax layer and pith film completely removed. Here, we carefully considered structural characteristics of bamboo, including internode and node areas at bamboo skin (BS) and pith ring (BP) sides. Dynamic contact angles were measured to evaluate surface wettability. In contrast with the unsanded surfaces, contact angles of sanded bamboo surfaces significantly declined at the end moment of 12s. Interestingly, node areas at BS and BP sides basically exhibited lower contact angles after sanding than internode areas. Surface morphology is a key component of surface creation, the impact of which on the wettability was studied. Specifically, mechanical sanding caused noticeable plowed ridges and much micro-fibrillation, leaving anatomical cavities like fractured vessels and pits exposed. Surface roughness was measured by a non-contact 3D profilometer with parameters of Sa, Ssk, Sku, Str, Sdr, Spc. The quantitative analysis presented that the Sa and Sdr values of sanded surfaces can be sorted as P60 > P80 > P120. Importantly, the results indicate that a rougher bamboo surface with greater Sa does not definitely result in better wettability. Detailed information on surface creation should be taken into account.
PubDate: 2024-08-02
DOI: 10.1007/s00107-024-02128-5
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- Lipophilic and polar extracts in the cork-rich bark of the Miombo species
Parinari curatellifolia-
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Abstract: Abstract The Miombo species Parinari curatellifolia has a bark with a cork-rich rhytidome that was studied here for the first time regarding extract yields and composition, using the complete rhytidome and also the separated cork fraction. The objective was to analyse their potential as sources of extracts with antioxidant activities aiming at increasing the species’ valorization and our knowledge on cork-rich barks.The content in total extractives was 6.1% and 8.4% in rhytidome and cork, respectively, with the lipophilic extracts soluble in dichloromethane corresponding to 23% and 38% of the total extracts, respectively. In cork, triterpenes and sterols were the main families of lipophilic components (58.9% and 20.8% of all compounds, respectively) while the rhytidome lipophilic extracts had a much higher content of long-chain lipids, including alkanoic acids and ɑ,ω-diacids (28.8% and 7.0%, respectively), with terpenes representing 27.7% and sterols 8.4% of all compounds. Aromatics were also present in significant amounts of 12.1%. Triterpenes included compounds known for various therapeutic properties, e.g. betulinic acid, corosolic acid, maslinic acid and ursolic acid, thereby explaining the use of P. curatellifolia in traditional medicine. Ethanol-water extracts contained phenolics, flavonoids, and tannins, and showed low (cork) or good (rhytidome) antioxidant properties. The outerbark of P. curatellifolia is therefore a potential source of bioactive compounds.
PubDate: 2024-08-02
DOI: 10.1007/s00107-024-02119-6
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- The effect of wood particles polyesterification with sorbitol and citric
acid on the properties of particleboard produced with the use of PF/pMDI
adhesive-
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Abstract: Abstract This study investigated the effect of pine particle polyesterification with the mixture of sorbitol and citric acid (SCA) on the properties of particleboard bonded with the PF/pMDI hybrid resin. The use of SCA with a concentration of 35% contributed to improvement in the internal bond of the particleboards, their water resistance and dimensional stability. However, lowering the concentration to 25% resulted in a deterioration of the properties of produced materials. The effect of different loadings of pMDI in the PF/pMDI resin (0%, 5%, 15%, 25%) was also investigated and the outcomes showed a positive effect of the share of 15% and 25%. Furthermore, boards made of treated particles were characterized by slightly better flammable properties (lower mass loss, flashing point temperature and delayed ignition), and the visibility of the effect increased with the increase in the concentration of the impregnate. The results also indicate that the introduction of pMDI may also influence the ignition of the board.
PubDate: 2024-08-01
DOI: 10.1007/s00107-024-02124-9
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- Correction: Study on vibration performance and comfort of glulam beam and
deck floor-
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PubDate: 2024-08-01
DOI: 10.1007/s00107-024-02084-0
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- Potential applications for eco-friendly wood preservative of the extracts
of thermally degraded cobs and stalks of corn-
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Abstract: Abstract While traditional wood preservatives may impede wood decay, their potential harm to both human health and the environment has led to limitations in their usage. This has spurred recent research to focus on seeking wood preservatives derived from plants, owing to their inherently eco-friendly attributes. Agricultural waste such as corn stover fractions, are not only abundant but also frequently underutilized, making them promising candidates for such endeavors. This study delves into the antifungal properties of extracts derived from thermally degraded corn stalk and corn cob. The selection of optimal raw materials and the identification of the most effective thermal degradation process were determined based on their inhibitory activity against Gloeophyllum trabeum (Pers.: Fr.) Murr. and Trametes versicolor (L. ex Fr.) Quél. Gas chromatography-mass spectrometry (GC-MS) was employed to analyze the composition of corn cob extracts resulting from various thermal degradation processes. The evaluation of decay resistance involved wood decay resistance tests and electron microscope observations. Results indicated that ethanol extracts from corn cobs heat-treated at 220 °C exhibited the strongest antifungal activity, accompanied by the highest extract yield. Additionally, the corn cob extracts also demonstrated inhibitory effects on the growth of Aspergillus niger, Escherichia coli, and Staphylococcus aureus. Chemical analysis revealed significant quantities of vanillin, squalene, and other compounds known for their antifungal or antibacterial activity in the corn cob extracts. Furthermore, wood treated with these extracts exhibited improved decay resistance, surpassing that against G. trabeum compared to T. versicolor. These findings suggest that thermally degraded corn cob extracts can be utilized as environmentally friendly wood preservative.
PubDate: 2024-08-01
DOI: 10.1007/s00107-024-02072-4
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- Manufacturing bamboo spur gears and assessing dynamic performance
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Abstract: Abstract This paper details the manufacturing and dynamic performance evaluation of bamboo spur gears utilizing bamboo powder. The research involved a comparison between the accuracy and dynamic performance of a bamboo gear and a POM gear. Initially, a disk-shaped preformed bamboo product was created and transformed into a gear using a gear hobbing machine. Subsequently, the gear's accuracy was assessed, and the dynamic gear testing machine was employed to measure gear temperature, generation noise, and wear volume. The bamboo gear produced in this study exhibited accuracy nearly equivalent to that of the injection-molded POM gear. The wear volume of the bamboo gear was reduced by elevating the molding temperature. Furthermore, the bamboo gear fabricated at 200 °C, under torque conditions of 0.5 Nm and 1.0 Nm, with a range of revolutions from 500 to 1500 rpm, demonstrated comparable performance in terms of temperature, noise, and wear to that of a POM gear. However, gears comprised entirely of bamboo powder proved incapable of withstanding a load torque of 1.5 Nm. This limitation stemmed from the fact that the flexural strength of POM was 90 MPa, whereas that of the bamboo powder molding product was 60 MPa. Therefore, when fabricating a bamboo gear using bamboo powder reinforced with bamboo fiber bundles, it withstood up to 107 rotations even under a load torque of 1.5 Nm.
PubDate: 2024-08-01
DOI: 10.1007/s00107-024-02060-8
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- Use of carbonated cellulose micro/nanofibrils in the coating of sack kraft
paper-
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Abstract: Abstract Coating paper with cellulose micro/nanofibrils (CMF/CNF) can improve the performance of paper packaging. However, the cost of the process is high due to the significant energy consumption during the CMF/CNF production process, which can be reduced through pre-treatment of cellulosic fibers. The objective of this work was, therefore, to evaluate the performance of CMF/CNF subjected to accelerated carbonation with different concentrations of calcium hydroxide (5% and 10% m/m) as a paper coating for packaging production in terms of spreading properties of adhesives, air permeability, and water absorption. The CMF/CNF coating was able to fill pores contained in the papers, with the treatment with 10% carbonation (CMF/CNF 10%) being the one that adhered best to the surface. There was a reduction in surface roughness from 1.35 ± 0.53 μm (uncoated paper) to 0.72 ± 0.21 μm (CMF/CNF 10%). Similarly, air permeability in the coated treatments was decreased, indicating good barrier properties and possible CO2 absorption activity in the carbonated samples. Coated papers showed greater spreading of water, PVA, and PVOH. On the other hand, the Cobb value dropped from 41.55 ± 3.83 g m2 (uncoated paper) to 26.26 ± 2.36 g m2 (CMF/CNF 10%). CMF/CNF subjected to pre-treatment with accelerated carbonation have the potential for use as a coating material, being recommended for applications in food packaging and those that will be subjected to gluing/coating processes with other materials.
PubDate: 2024-08-01
DOI: 10.1007/s00107-024-02068-0
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- Experimental study of hybrid pine-birch glued-laminated timber beams
assisted by digital image correlation technique-
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Abstract: Abstract This paper presents an experimental study on the flexural behavior of hybrid Pine-Birch Glued-Laminated Timber (GLT) beams. The study focuses on the performance of GLT beams with different lengths (2.1 and 2.8 m) and different compositions of birch (30 and 50%) and pine lamellas. The experiments were conducted using a four-point bending test and data were analyzed using Linear Voltage Displacement Transducers and Digital Image Correlation techniques. The results highlight that pure pine GLT beams exhibited brittle failure, while pure birch beams displayed a more ductile behavior. The hybrid GLT beams demonstrated a transitional behavior between the two. The presence of birch lamellas in the hybrid beams highlights the potential of these beams in structural applications, and significantly improves the global bending modulus of elasticity, bending strength, and flexural ductility compared to pure pine beams.
PubDate: 2024-08-01
DOI: 10.1007/s00107-024-02063-5
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- Application of the TOPSIS decision-making method for selecting a
manufacturing technique for children’s furniture elements with
therapeutic functions-
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Abstract: Abstract Making furniture or furniture elements that account for the needs of children at various stages of development or with psychomotor dysfunctions is very difficult. From the point of view of exploitation and production technology, it is difficult to select a specific material and manufacturing technique. In this article, the results of using the APEKS method, which is a type of Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method, are presented to select the best solution for the production of children’s furniture elements with surface structures similar to those of natural materials. Wood bark was selected as a material that, due to the sensory tactile sensations of dysfunctional children, could contribute to therapy and education. Comparative analysis was performed on the basis of the subtractive and additive methods used for manufacturing furniture products. Precise multiaxis milling of ash wood and 3D printing with fused filament fabrication technology using wood PLA filaments were carried out. The method used to select the best option considered quantitative and qualitative criteria in the assessment. Various parameters characterizing the surfaces were analyzed, such as geometric dimensions, hill heights, valley depths, and 3D surface parameters. The quality and surface roughness (Sa, Sz, Ssk, Sku, Sp, and Sv) parameters obtained based on 3D microscope measurements were determined. A scale of 1 to 10 was used to assess qualitative factors (i.e., usability and aesthetics). Based on the critical values obtained from the coefficient Kcri = 79.36, it was assumed that multiaxis wood milling was the best method for producing furniture elements with the required surface characteristics for use as therapeutic and educational tools for children with dysfunctions. The applied method allowed an effective evaluation of the compared variants of the production of furniture elements for customized applications.
PubDate: 2024-08-01
DOI: 10.1007/s00107-024-02082-2
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- Using machine learning as an adaptive controller framework for optimizing
properties of particleboard-
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Abstract: Abstract Fine adjustment of manufacturing parameters as a function of the experience of the technical manpower plays a vital role in any production line. The objective of this study was to propose an adaptive controller framework to improve the overall accuracy of the parameters regulating particleboard manufacturing. This framework has four main steps: (1) In the data gathering process, the production parameters and the sample test results were collected from the randomly picked and tested specimens in each round, (2) Relevance analysis was used to select high-power relevant variables influencing the overall quality of the final product. Those relevant variables will be inputs to construct the classification model, (3) A decision tree was employed to construct the classification model and reveal split points of the process parameters to determine the distinction between passed and failed panels, and (4) The production parameters in the next round will be adjusted according to the defined split points so the quality of the particleboard can be enhanced. Continuous improvement of the production parameters, within the perspective of the proposed framework, enables us to go back to step (1) again as desired, especially in the long production run. Based on the findings of this work, the experimental results revealed that the model could classify the failed particleboard with a specific rate of 92.50%. The model also demonstrated that resin characteristics, namely pH value and viscosity, impacted the overall performance of the particleboard.
PubDate: 2024-08-01
DOI: 10.1007/s00107-024-02059-1
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- Trichoderma atrobrunneum associated with yellow stain defect of cork
planks and critical values of TCA for wine cork stoppers industry-
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Abstract: Abstract Cork planks with Yellow Stain (YS) defect are rejected from cork-stopper factory industries resulting in large economical losses. This defect has been related to 2,4,6—trichloroanisole (TCA), a chemical compound responsible for an off-flavor aroma in wine known as cork taint. The relation between YS and TCA was confirmed by the analyzes carried out in this work. Considering that fungi have the capacity to convert trichlorophenol into TCA, raw cork planks were collected in a factory and the mycobiota was searched using morphological and molecular methods. Eight genera and order of fungi were obtained and statistical analysis revealed that the Trichoderma genus is significantly related to TCA levels critical for industry, in particular the species Trichoderma atrobrunneum, a fungus belonging to Trichoderma harzianum complex. To our knowledge, this is the first report associating T. atrobrunneum to high TCA levels and YS defect of cork.
PubDate: 2024-08-01
DOI: 10.1007/s00107-024-02070-6
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- Local stability of glued laminated bamboo columns with box sections under
axial compression-
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Abstract: Abstract Laminated bamboo columns with box sections are favored by designers because they overcome the disadvantage of small elastic modulus, but local buckling behavior caused by an excessive width-to-thickness ratio will lead to a non-uniform distribution of stress. The discontinuous cracks at the glued joints and waveform deformation indicate that the local buckling has a significant effect on the bearing capacity of columns with box sections. However, few studies have been reported on the evaluation of bearing capacity considering local stability due to non-uniformity and discontinuity. The experiments on 5 glued laminated bamboo columns with box sections (GLBCs) with different length-to-width ratios under axial compression were carried out. The test results showed that the waveform bulging failure occurred on the surface of GLBCs before the overall buckling, and an obvious debonding failure occurred between the bamboo plates. These failures aggravated the local buckling failure. As the length-to-width ratio increased, the number of waveforms buckling increased, the lower the bearing capacity. To evaluate the local stability of GLBCs accurately, a new anisotropic plate model considering the width correction coefficient and material anisotropy for the critical buckling load of GLBC was proposed. Furthermore, it can be found that an appropriate width-to-thickness ratio can effectively avoid local buckling failure. A formula for the critical width-to-thickness ratio of GLBCs under different slenderness ratios was proposed. In this paper, the anisotropic plate model proposed can accurately evaluate the bearing capacity considering the local stability of GLBCs under axial compression.
PubDate: 2024-08-01
DOI: 10.1007/s00107-024-02066-2
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- A Fully Coupled Numerical Model for Unbonded Post-tensioned Timber
Structures-
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Abstract: Abstract The paper presents a fully Lagrangian mesh-free solver to simulate the dynamic behavior of post-tensioned timber structures. Weakly Compressible Smoothed Particle Hydrodynamics (SPH) is employed to model both the timber and the tendon. An efficient and simple coupling method between the timber and the tendon is proposed by considering the numerical stability. Besides, the same coupling algorithm is used to model the interaction between column and beam elements. Although the column is treated as rigid in the simulations, the coupling algorithm accounts for the initial compression of the column resulting from post-tensioning. For the verification of the code for solids and material nonlinearity of timber, benchmark problems available in the literature are used. Finally, the solver's capability is demonstrated through dynamic analysis of post-tensioned timber structures. The solutions obtained for all the cases are in good agreement with the experimental and theoretical data, which indicates the applicability and accuracy of the solver.
PubDate: 2024-08-01
DOI: 10.1007/s00107-024-02073-3
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- Development of bentonite-based organo-geopolymer hybrid wood binder
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Abstract: Abstract The study addresses concerns associated with formaldehyde-based adhesives in wood panel board production by proposing geopolymer-based wood binders as promising, formaldehyde-free alternatives. Using bentonite, the research delves into the development and performance properties of this geopolymer wood binder. The BET method was employed for the surface characterization of precursor raw materials for binder preparation. Si and Al elements identified through XRF analysis were correlated with characteristic bands in the FTIR spectrum. Alkaline activation solutions, employing sodium silicate and sodium hydroxide with a molar ratio range of 0.5 to 2.5 (SiO2:Na2O), revealed that binders with a molar ratio of 2.5 exhibited lower pH and higher adhesion strength. Different geopolymer formulations at solution to powder ratios (s/p) of 1.33, 3, and 3.5 determined s/p 3.5 as optimal for bentonite-based organo-geopolymer binders. Viscosity, gel time, pH, and solids content were examined, showing the effectiveness of substituting 10% silica fume to enhance the geopolymerization process and improve adhesion. Modifications using citric acid, sucrose, paraffin, pMDI, triacetin, and resorcinol demonstrated wet bonding strength comparable to urea formaldehyde adhesive. Analytical techniques, including FTIR spectroscopy, XRD analysis, and SEM EDX analysis, provided insights into functional groups, crystallographic properties, and microstructural characteristics. The concentration of Si and Al compounds on the bonding line, coupled with Na element diffusion, was observed through these analyses. Light microscopy of lap shear samples revealed a thinner bonding line, affirming effective binder penetration into wood cell lumens in bentonite-based organo-geopolymer binder formulations.
PubDate: 2024-08-01
DOI: 10.1007/s00107-024-02078-y
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