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Ultra-lightweight foam-core fibreboard with 19 mm thickness was produced with a novel one-step process using resinated wood fibres for the faces and expandable polystyrene (EPS) as core layer material. The aim of the current study was to investigate the panel properties produced with different EPS bead diameter (0.5, 1.5, and 2.5 mm) and surface layer thickness (1, 2, 3, 4, and 5 mm). The EPS bead diameter showed a significant effect on the properties of foam-core fibreboard. The most uniform foam with the smallest cell size and highest cell density was observed in panels with smaller EPS beads, which also resulted in a remarkable increase in bending strength and edge screw withdrawal resistance (SWR) of the foam-core panels. Increasing the surface layer thickness from 1 to 5 mm significantly raised the foam-core panels’ density from 220 to 460 kg/m3, respectively. The higher the panel density, the higher the bending properties and the face SWR. The physical properties (thickness swelling and water absorption) of foam-core panels were negatively influenced by thickening of the surface layers. In general, foam-core fibreboards made with smaller EPS beads (0.5 mm) and 3 mm surface layers (density of 340 kg/m3) showed excellent potential for furniture manufacturing due to their acceptable properties according to EN622-5/P1 while still having nearly 55% lower density compared to conventional fibreboard density (750 kg/m3).

This study was aimed to evaluate the position of lightweight panels and their application in furniture production in Iran by investigating consumers’ behavior and preferences. Here, consumers’ preferences toward effective criteria to choose furniture made of wood-based panels (WBPs) were evaluated on the basis of analytical network process method. Furthermore, respondents were asked about their attitudes and preferences regarding lightweight furniture. The results revealed that the main sub-criteria for buying furniture were product quality, design, price, environmentally-friendly, and guarantee features. Furthermore, the technological feature was the most important criterion affecting consumers buying decisions more than the visual/appearance and economical features of the furniture. Consumers believed that conventional WBPs were heavy for some applications in the furniture. Respondents emphasized that they would buy lightweight furniture, even with a bit more price (5–9%) in comparison to conventional furniture (furniture made of WBPs) if there would be a product guarantee, more varieties of the products available in the market, and environmentally-friendly certification. In general, the consumers showed a willingness to buy furniture made by panels with mid-range density (480 kg/m3 density), but they should have to be sure of the panels’ quality and the furniture made thereof before buying this product.

Lightweight panels, as an eco-friendly element for furniture manufacturing, offer several potential market and production opportunities for many secondary woodworking companies. In this study, the perceptions of Iranian furniture manufacturers were evaluated by means of ANP-based multi-type questionnaires, regarding the conditions and requisite features of lightweight panels in furniture manufacturing. The ANP results revealed that product design, quality and price were effective sub-criteria for furniture manufacturers. The most important attributes for choosing panels during the manufacturing process were: lack of panel warping, product abundance in the market, and withdrawal resistance of connectors. Manufacturers indicated that they were aware of the advantages lightweight panels would bring them, but they were still in need of further persuasion concerning the quality and workability of lightweight panels. Combining lightweight and conventional panels for furniture manufacturing could lead to an increased interest in assuring furniture quality. In addition, further development of lightweight panels is necessary to increase the variation in the market.

The hybridisation of wood-based panels has gained interest in recent years. Lightweight hybrid panels consisting of wood fibres as faces and a mixture of wood particles with expandable polystyrene ...

Chitosan was used as environmentally friendly and bio-based scavenger for reducing the formaldehyde emission from medium density fiberboard. Using of chitosan powder showed better capacity of formaldehyde adsorption rather than the chitosan solution. Liquid 13C-NMR showed that the free formaldehyde in urea formaldehyde adhesive having chitosan powder was drastically reduced. Additionally, the observed peak at 155 ppm showed that that the chitosan powder was copolymerized with urea formaldehyde adhesive. Increasing the amount of chitosan powder was significantly reduced the emitted formaldehyde. It was shown that the formaldehyde adsorption of chitosan was strongly influenced by the pH value of adhesive composition. The pH value and the adhesive gel time tended to increase with addition of chitosan powder, due to the proton affinity of chitosan. The mechanical and physical properties of panels did not significantly change when the chitosan content as scavenger was raised up to 3%, while a formaldeh...

Low density hybrid panels (16 mm thickness) were produced using wood fiber as face layers and a mixture of coarse wood particles and expandable polystyrene (EPS) as core layer. The EPS was foamed (in-situ foaming) in the core layer during the pressing stage. The effects of granules diameter (0.4, 0.8, 1.15, 1.5, and 2.2 mm) and granules content (5, 10, and 15%) on the physical and mechanical properties were evaluated. The results showed that both variables had significantly influenced the panels’ properties. Mechanical properties mostly depended on the level of mechanical inter-locking of EPS with wood particles, while the physical properties were mostly influenced by the EPS distribution. Stronger mechanical inter-locking of EPS with wood particles was achieved by both larger diameter and higher amount of EPS granules (2.2 mm and 15%). A better EPS distribution between the wood particles was observed with the smaller EPS granules and higher amount of EPS (0.4 mm and 15%).

A simulated one-step process has been developed for the production of foam core particleboards using rigid polyurethane as the core layer. The results showed that the different techniques used for surface layer separation (unresinated particles and sprayed water) and foam injections (open system and closed system) had no influences on panels’ characteristics. Mechanical properties (e.g., bending strength and internal bond strength) were mostly influenced by the surface layer thickness, while the water absorption and edge screw withdrawal were influenced by the foam cell structure. The use of sprayed water for surface layer separation doubled the formaldehyde emission (FE) of the panels. The addition of urea (based on 10% of the dry resin) to the sprayed water had a positive effect of reducing the final FE. Furthermore, increasing the surface layer thickness had a positive, linear relationship with FE.

Transforming waste or recycled materials into value-added products is of high priority today. Wood plastic composites (WPCs) show high potential for the use of recycled materials in making durable composites. The applicability of WPC panels produced from recycled materials (ultralight foam core particleboards) for exterior building application was tested using wood-destroying basidiomycetes. The results showed that the panels were fully resistant against Coniophora puteana (Cp) and Gloeophyllum trabeum (Gt), but not very resistant against Pleurotus ostreatus (Po). The decay susceptibility index of Po-exposed specimens showed that the polystyrene-bonded (PS) samples were more resistant than solid beech wood samples that were used as references, followed by melamine-urea formaldehyde-bonded samples. A comparison with the reference samples also showed that the panel density had a significant influence on the panel’s resistance against basidiomycetes. The higher the panel density, the more resistance will be achieved in the panel.

Geopolymer binders are an emerging class of mineral polymer that can be manufactured from natural raw materials and industrial byproducts containing high amounts of silica (Si) and alumina (Al) in mineral compositions. Various ratios of materials used for manufacturing geopolymer binder have been tested to evaluate the bonding performance of geopolymers with wood by means of tests performed on an automated bonding evaluation system (ABES). Tests with a binder based on sodium silicate water glass (Na 50T) are partly promising, which resulted only 10% lower shear strength than that based on urea formaldehyde. The binder characteristics were significantly influenced by changing the ratio of SiO2:M2O (M=Na or K) and the ratio solid content to chemical base in the water glass. Expectedly, increasing press temperatures and pressing times showed a positive correlation with the curing performance of geopolymer binder. It was also demonstrated that the binder properties can be changed in wide ranges to obtain binders which fulfill the minimum requirements set by industrial users.

Geopolymers show good potential to be used as free formaldehyde-based binder to produce wood-based panels. Hence, the objective of this research was to investigate the geopolymer composition as binder on the physical and mechanical properties of multi-layered plywood. The geopolymer binder was prepared based on kaolin and metakaolin as the major aluminosilicate powder that were substituted with different contents of silica fume. The results showed that the substitution of aluminosilicate with silica fume (up to 20% based on weight) in the geopolymer mixture modified the chemistry of the geopolymerisation, and hence, improved the amorphous structures of the geopolymer binder. In summary, the substitution of aluminosilicate with silica fume (up to 20% based on weight) in the geopolymer mixture improved the geopolymer binder cohesion, reduced the binder viscosity, reduced the binder curing time, increased the binder penetration into the superficial wood cells, increased the binder shear strength, increased the bending strength of plywood, and accordingly, reduced the plywood stiffness. Notably, none of the plywood samples did delaminate even after 672 h water immersion, implying that the geopolymer binder-based products have a better stability in water compared to some organic binders (e.g., adhesives based on tannin, soya and starch), which suffer from hydrolysis after immersion in water. All in all, the geopolymer binder based on metakaolin showed promising potential to be used as formaldehyde-free binder to produce plywood.

One-step manufacturing process (in-situ foaming) provide great potential for the production of foam core panels. Polyurethane (PU) foam showed good applicability for use for in-situ foaming. Here, the effect of ingredient ratios of rigid PU foam on foam performance and panel properties is investigated. It was observed that the isocyanate (ISO) content and polyols (PO) type and content significantly change the foam and panel properties. Foam cell density, as the most important factor influencing the foam characteristics, was higher in foams with higher ISO and polyether content. Bending strength, internal bond and screw withdrawal resistance of the foam core panels were significantly enhanced when the ISO and polyether content was increased in the foam formulation. Varying the ISO content had no influence on panel properties with higher content of polyester (60%) in the PO blend. Varying the foam ingredient ratios did not change the thickness swelling, while the water absorption was dependent on the foam components ratios. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44722.