Search Results (117)

Flame-retardant coatings and films are widely used to delay flame spread on interior finishing and wood-based materials; however, their fire effluent toxicity has not been sufficiently characterized, and direct comparisons between these product types remain scarce. This study evaluated three commercial flame-retardant coatings and three flame-retardant films using the KS F 2271 gas toxicity test, NES 713 toxicity index test, and Py-GC/MS and HS-GC/MS analyses. Representative coating and film products were also applied to medium-density fiberboard (MDF) to assess average incapacitation time, total smoke release (TSR), and total heat release (THR). All tested specimens, including the 1 coat/layer, increased-loading, and MDF-applied conditions, satisfied the Korean gas toxicity criterion of 9 min. However, increased loading affected the two product groups differently; the intumescent coating showed a marked reduction in average incapacitation time, whereas the films remained relatively stable. The coatings produced higher toxicity indices and more diverse detected gases and pyrolysis products than the films. In MDF-based specimens, flame-retardant treatment increased average incapacitation time and reduced TSR and THR. These findings show that fire effluent toxicity differs between coatings and films and should be considered together with flame-retardant performance. Full article

The valorization of post-consumer waste materials is an important strategy for reducing environmental impact and supporting circular material use. In this study, lightweight sandwich composites were developed using recycled paper and cardboard as core materials, producing sustainable panels for thermal and acoustic insulation. Core panels were manufactured from 100% paper, 100% cardboard, and a 50–50% paper–cardboard mixture. Environmentally friendly foaming agents were added to increase porosity and reduce density. The cores were subsequently combined with 3 mm medium-density fiberboard (MDF), 1 mm oak veneer, and date palm midrib fibers to provide different surface characteristics. The resulting sandwich composites were evaluated through standardized measurements of thermal conductivity and sound absorption coefficients. Microstructural characteristics were investigated using stereomicroscopy and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM–EDX). The results indicate that both the core composition and the type of face layer influence their performance. Whilst composites with cardboard-rich cores had higher porosity and better thermal insulation, introducing perforations and increasing the panel thickness improved sound absorption. The findings demonstrate that recycled paper and cardboard can be effectively used as sustainable raw materials to produce lightweight sandwich composites, tested at material scale, for non-structural interior insulation/acoustic panels. Full article

The sound reduction index R is commonly determined using standardized laboratory procedures developed primarily for full-size building elements. However, in many research and development applications, including technical enclosures, lightweight panels, modular components, and new acoustic materials, only reduced-size specimens are available. In such cases, the influence of specimen dimensions and test-opening geometry on the measured sound insulation is not yet fully understood. This study investigates the effect of specimen size and geometry on the measured sound reduction index using a dedicated small-scale coupled reverberation room stand. Measurements were performed for five materials with different mechanical and structural properties: steel, polymethyl methacrylate (PMMA), medium-density fiberboard (MDF), gypsum board, and Sylomer. Six test openings were analyzed, including three square openings, one quasi-square opening, and two rectangular openings. The results show that specimen dimensions can significantly affect the measured values of R, especially in the low-frequency range, where modal behavior, boundary conditions, and the relationship between specimen dimensions and acoustic wavelength are important. The influence of specimen size was material-dependent and was more pronounced for stiff plate-like materials than for the highly compliant Sylomer specimen. Comparisons between square and rectangular openings with similar surface areas suggest that, within the investigated range of materials, specimen geometries, and measurement conditions, specimen surface area had a greater influence on R than specimen shape, although geometry can still contribute to the measured differences. The repeatability analysis confirmed that the measurement stand is sensitive to differences related to material type, specimen dimensions, and installation conditions. The proposed methodology may be particularly useful for comparative studies of novel acoustic materials and prototype building elements when only reduced-size specimens are available during the early stages of material development. The results support the use of small coupled reverberation rooms for comparative testing and preliminary material screening, while also showing that reduced-size sound insulation measurements require careful interpretation and cannot be treated as direct substitutes for full-scale standardized tests. Full article

The increasing demand for sustainable and lightweight furniture systems has driven interest in additively manufactured polymer components as alternatives to conventional metal hardware. However, their performance at the functional assembly level under standardized loading conditions remains insufficiently explored. This study evaluates the feasibility of replacing metal drawer slides with fused deposition modeling (FDM)-based polymer alternatives fabricated from polylactic acid (PLA) and polyethylene terephthalate glycol (PETG). Unlike previous studies focused on material-level characterization, this work investigates fully functional drawer slide assemblies integrated into medium-density fiberboard (MDF) systems, enabling component-level assessment under realistic conditions. Specimens were designed in SolidWorks and fabricated under controlled printing parameters. Commercial metal slides were used as benchmarks. Mechanical performance was tested according to BS EN standards, and deformation was measured at multiple points. Statistical analysis included ANOVA, Tukey HSD, and t-tests at a 95% confidence level. Results showed significant differences among materials (p < 0.05). Metal slides exhibited the highest stiffness and minimal deformation. PLA showed stable performance with minor surface degradation, while PETG demonstrated lower dimensional stability and premature failure due to higher compliance. Overall, PLA-based FDM components offer a cost-effective alternative for non-heavy-duty applications, whereas PETG requires further optimization. The study bridges additive manufacturing and real-world furniture component performance under standardized testing. Full article

Powder coatings applied to medium-density fiberboard (MDF) substrates have attracted increasing attention due to their low volatile organic compound (VOC) emissions and high material utilization efficiency. The review synthesizes the interdisciplinary literature from coating engineering, CMF design, and furniture design. However, existing studies often focus on individual coating properties and lack a systematic framework integrating color, material, and finish (CMF). Therefore, this review examines the design and application of MDF powder coatings from a CMF perspective, focusing on the relationships between coating engineering parameters and user-oriented perceptual requirements. Within this framework, color performance is associated with pigment dispersion and particle size distribution; the material dimension is governed by low-temperature curing kinetics and substrate properties, and the finish dimension is shaped by surface texturing and functional additives. The review also discusses current limitations, including the trade-off between low-temperature curing reactivity and storage stability, the influence of nano-additives on surface quality, and the recyclability challenges of powder-coated MDF. Future research should focus on industrial scalability, lifecycle sustainability, and long-term durability of MDF powder coating systems. This review provides a CMF-oriented framework for linking user experience requirements with coating engineering strategies, which is of great importance for the development of customized home furnishing. Full article

This bibliometric study examined 179 Scopus-indexed publications on the physical and mechanical properties of medium-density fiberboard (MDF) published between 2016 and 2025. BiblioMagika^® was used for performance analysis, and Biblioshiny was used for keyword co-occurrence, thematic mapping, and thematic evolution. The papers identified as the cohort for analysis had received 2830 citations in total, with an average of 15.81 citations per paper, and an average h-index of 30. The European Journal of Wood and Wood Products and BioResources were the most productive sources. Three distinct categories were identified through keyword mapping among the studies reviewed: (1) advanced composites and reinforcement, (2) adhesive and emission-related studies, and (3) circular-material strategies. Thematic evolution showed a trend away from traditional resin-performance topics toward broader sustainability-related themes, particularly bio-based adhesives and recycling-related topics. Overall, this review provides a quantitative overview of publication patterns, influential sources, and thematic development in MDF research. It also provides direction for future MDF research, focusing on durability, large-scale feasibility, life-cycle assessments, and practical implementation. Full article

The global shift toward sustainable industrial processes has increased the demand for advanced materials capable of performing under harsh conditions, with high-temperature polymer nanocomposites emerging as a key development area. This study investigates the fabrication of sustainable polysulfone (PSU)/medium-density fiberboard (MDF) nanocomposites through phase inversion, using PSU—a matrix known for its high glass transition temperature—as the base. Membranes were created by adding MDF residue at 1, 3, 5, 7, and 10 phr (parts per hundred resin). Characterization included analyzing polymer solution viscosity, ATR-FTIR, contact angle, SEM, porosity, equilibrium water content, average pore radius, tensile testing, and permeation performance. Incorporating MDF residue increased solution viscosity and affected porosity and the structure of the top layer. Mechanical testing showed MDF acted as a functional additive, improving the elastic modulus and tensile strength, and supporting overall structural stability under hydraulic stress. The membranes exhibited competitive water flux and maintained high selectivity (80–92% rejection; over 95% turbidity removal) at 1.0 and 2.0 bar. The 3 and 5 phr levels optimized performance, demonstrating that repurposing industrial waste within high-performance matrices is a practical approach for producing durable materials that meet the needs of energy systems and complex industrial separation processes. Full article

Ultra-low-formaldehyde medium-density fiberboard (MDF) is commonly produced using low-molar-ratio urea-formaldehyde (UF) resins; however, the reduced formaldehyde-to-urea ratio also lowers resin reactivity and can complicate curing. The aim of this research work was to investigate and evaluate the performance of ammonium bisulfite and urea–metabisulfite as formaldehyde scavengers for a low-molar-ratio UF resin (F/U = 1.06) at 1, 3, and 5 wt% (based on dry UF resin solids) used for MDF panel manufacturing. The modified adhesive systems were first screened by simultaneous thermal analysis in air to determine changes in the curing profile, and laboratory panels were then produced and evaluated for formaldehyde content by the perforator method (EN ISO 12460-5:2015) and for the main physical and mechanical properties. Ammonium bisulfite shifted the main curing peak to higher temperatures, indicating stronger retardation of the principal polycondensation stage, whereas urea–metabisulfite generated a broader, multi-peak curing profile. Despite these differences, both additives reduced the perforator values substantially. The control MDF already met the E0 level (3.84 mg/100 g oven-dry board), while 3 wt% ammonium bisulfite and 5 wt% urea–metabisulfite reached the super E0 levels (<1.5 mg/100 g; 1.36 and 1.26 mg/100 g, respectively). To note, scavenger addition up to 5 wt% (based on dry UF resin solids) did not significantly affect density, water absorption/thickness swelling, or bending and internal bond properties. The results demonstrate that sulfite-based scavengers can be incorporated into low-molar-ratio UF adhesives to obtain ultra-low-formaldehyde MDF while maintaining the main panel properties. Full article

Conventional life cycle assessment (LCA) of wood products often lacks a dynamic representation of biogenic carbon flows, leading to an oversimplified account of their climate impact. This study introduces a novel methodological framework by integrating a four-stage carbon storage cycle (carbon sequestration, first carbon emission, extension of carbon storage, and second carbon emission) with the ISO 14067:2018 standard for product carbon footprinting. We developed a transparent calculation model to partition CO₂ emissions across production, transportation, and disposal stages using a representative medium-density fiberboard (MDF) production case in China for empirical validation. The results reveal a total emission of 32.8135 kg CO₂/m², with a striking 59% originating from the disposal and recycling stage, overshadowing production (39%) and transportation (2%). This finding underscores the critical, yet often neglected, role of end-of-life management in the carbon footprint of manufactured wood panels. The study provides a replicable template for dynamic carbon accounting of wood products. Full article

The aim of this study was to determine the effects of hygiene (H) and nano-color pigment (NCP) modifications on hardness, glossiness, and adhesion strength of some surface coating materials produced specifically for use in wooden toys. For this purpose, H- and NCP-modified polyurethane (PU) and waterborne (WBV) varnishes were applied to specimens prepared from Oriental beech (Fagus orientalis L.) and Oriental plane (Platanus orientalis L.) woods; Oriental beech, birch (Betula pendula), and poplar (Populus deltoides) plywood; and medium-density fiberboard (MDF). Then, hardness, glossiness, and adhesion values were determined. Results indicated that the highest values were obtained for hardness in PU and PU*NCP applied to MDF; for glossiness in WBV*H applied to birch plywood and MDF; and for adhesion strength in WBV and PU*H applied to beech. H and NCP modifications have significant effects on hardness, glossiness, and adhesion strength. As a result, it was determined that hardness and glossiness increased with H modification and decreased with NCP, especially glossiness. Furthermore, it was determined that H and NCP decreased the adhesion strength. Future studies comparing natural antibacterial effects of different wood species with various coating types will contribute to the development of products that are safe for children and sustainable. Full article

The recovery of timber residues from abandoned underground coal mines presents a unique opportunity to expand the raw material base for wood-based composites, aligning with the principles of cascade utilization. Large amounts of structural wood, embedded for decades under anaerobic and humid mining conditions, remain remarkably well-preserved and can be valorized as a secondary feedstock. The aim of this work was to investigate and evaluate the feasibility of incorporating recovered mining timber into the production of medium-density fiberboards (MDFs). Six types of laboratory panels were produced, containing different ratios of recovered and virgin pine fibers (0–100%), bonded with melamine–urea–formaldehyde resin and hot-pressed at 180 °C. Comprehensive testing of physical and mechanical properties demonstrated that panels with up to 40% recovered fibers fully complied with European standards for general-purpose boards, while up to 60% substitution was acceptable with respect to internal bond strength. At higher substitution levels, however, dimensional stability and strength were significantly reduced. These findings highlight the potential of mine timber recovery as a viable raw material pathway for MDF manufacturing, extending the service life of wood resources and reducing pressure on primary forests. The study emphasizes the role of recovered biomass in advancing circular bioeconomy objectives and resource efficiency in the wood-based panel sector. Full article

This study presents a comparative analysis of a “design” speaker cabinet shape and a conventional block enclosure, both having identical internal volumes. Both enclosures were built from birch wood, and for comparison, block-shaped baffles were also made from medium-density fiberboard (MDF). While the designer’s new shape was handcrafted using a lathe, a cube baffle was made using a CNC machine. The block-shaped sound box was made as a representative of the classic shape that occurs most often in the world of music. For this reason, it is offered as an ideal reference sample of the enclosure for comparison with the new design proposal, which was produced based on the shape predispositions and the interest of potential customers. The loudspeaker systems were then subjected to anechoic chamber testing using the exponential sine sweep (ESS) technique to assess and compare their resonance characteristics. The box-shaped enclosure showed a smoother course of the frequency response, but the differences are not significant. A potential improvement in acoustic performance was offered by an acoustic dampening material that was incorporated into each enclosure, and the measurement was repeated. The drop shape from solid birch benefits most from filling, with an 8 dB reduction in low-end boom and 2 dB smoothing, resulting in more controlled bass. The cuboid of solid birch is quite stable even without filling, but filling still improves deep bass by ~3 dB and smooths mid-bass by ~2 dB. For comparison, the cuboid made of MDF shows the largest improvement with filling, with a 10 dB reduction in sub-bass peaks and 4 dB smoothing in dips. With the acoustic filling, the frequency curves are even more smoothed, and it can be said that the damping material can eliminate some of the imperfections of the enclosures. Full article

Coffee processing generates large volumes of spent coffee grounds (SCGs), which contain 30–40% hemicellulose, 8.6–13.3% cellulose, and 25–33% lignin, making them a promising lignin-rich filler for biocomposites. Conventional wood composites rely on urea-formaldehyde (UF), melamine–urea–formaldehyde (MUF), and phenol–formaldehyde resins (PF), which dominate 95% of the market. Although formaldehyde emissions from these resins can be mitigated through strict hygiene standards and technological measures, concerns remain due to their classification as category 1B carcinogens under EU regulations. In this study, fiber-based biocomposites were fabricated from thermomechanical wood fibers, SCGs, and ammonium lignosulfonate (ALS). SCGs and ALS were mixed in a 1:1 ratio and incorporated at 40–75% of the oven-dry fiber mass. Hot pressing was performed at 150 °C under 1.1–1.8 MPa to produce panels with a nominal density of 750 kg m⁻³, and we subsequently tested them for their physical properties (density, water absorption (WA), and thickness swelling (TS)), mechanical properties (modulus of elasticity (MOE), modulus of rupture (MOR), and internal bond (IB) strength), and thermal behavior and biodegradation performance. A binder content of 50% yielded MOE ≈ 2707 N mm⁻² and MOR ≈ 22.6 N mm⁻², comparable to UF-bonded medium-density fiberboards (MDFs) for dry-use applications. Higher binder contents resulted in reduced strength and increased WA values. Thermogravimetric analysis (TGA/DTG) revealed an inorganic residue of 2.9–8.5% and slower burning compared to the UF-bonded panels. These results demonstrate that SCGs and ALS can be co-utilized as a renewable, formaldehyde-free adhesive system for manufacturing wood fiber composites, achieving adequate performance for value-added practical applications while advancing sustainable material development. Full article

The aim of this study is to determine the hydrothermal recycling of medium-density fiberboard (MDF) wastes using zinc chloride (ZnCl₂) as an acidic catalyst to obtain reinforcing fibers for epoxy-based composites. For this purpose, during the hydrothermal recycling process (110 °C, 0.4 bar), zinc chloride solutions with different concentrations (0% to 30%) were applied at different time intervals (20 to 60 min). The recycled fibers were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope-energy dispersive spectrometry (SEM-EDS), carbon (C) (%), hydrogen (H) (%), and nitrogen (N) (%) contents, and fiber classification. The fibers were added as a filler (1% w/w) to epoxy composites. The compression strength and of the epoxy composites as assessed and differential scanning calorimetry (DSC) characterization was performed. According to the results, nitrogen content decreased with increasing ZnCl₂ concentration. Furthermore, the fine fibers ratios increased with increasing treatment time. The results suggest that recycled fibers can be used as a filler in epoxy composites; however, a long treatment time adversely affects the compression strength of epoxy composites. Full article

In this study, we investigate a novel post-processing approach combining heat annealing and powder coating to enhance both the mechanical performance and surface finish of polylactic acid (PLA) 3D-printed components. Previous work demonstrated that annealing PLA at temperatures between 100 and 120 °C significantly improves its mechanical properties. Building on this, we explore the effects of applying medium-density fiberboard (MDF) powder coating, which cures at a similar temperature range, to simultaneously improve the material’s surface aesthetics. Test specimens were printed with identical parameters and subjected to heat treatment at 120 °C for varying durations (0 to 15 min, in one-minute intervals). Additional observations included dimensional stability and surface uniformity. The results indicate a clear correlation between post-processing time and improvements in both strength and surface appearance, with optimal outcomes observed between 5 and 8 min of curing. This combined post-processing method provides a cost-effective and accessible way to enhance part performance and aesthetics, thereby expanding the applications of PLA-based additive manufacturing, particularly in functional and design-focused use cases. Full article