International Wood Products Journal

Members of the genus Albizia are used as shade trees in tea plantations as they exhibit various beneficial roles like adding nitrogen to the soil, moisture conservation, supplementing organic matter, besides providing shade. The bark of Albizia is considered waste resources as they do not have any known economic value. So, this experiment was carried out as an initiative to explore the possibility of valorisation of bark metabolites. Gas chromatography-mass spectrometry (GC-MS) was employed for detecting the bark metabolites. A total of 66 compounds including latex, alkaloids, resin, wax, terpenoids, etc. were detected, out of which 18 were from Albizia chinensis, 22 from Albizia lebbeck, and 26 from Albizia odoratissima. GC-MS also detected the presence of diacetone alcohol, a major compound that has commercial application in paint coatings, preparation of cleaning solvents, inks, pharmaceutical preparations, sealants, primers, and pesticides, preparation of artificial silk, leather, antifungals, etc. Thus, Albizia bark derived waste resources can be useful for industrial purposes if they can be cost-effectively isolated on a large scale.

This study investigated the effects of teak wood sawdust and polycarbonate (PC) additions on the mechanical properties, including tensile strength, elongation at break, flexural strength, and impact resistance of wood–plastic composites based on high-density polyethylene (HDPE) and compatibilised with 4 wt. % PE-grafted-maleic anhydride. The composites were fabricated via injection moulding, and an experimental design was conducted using the Taguchi L9 orthogonal array method. Three factors were studied: PC content (0, 7.5 and 15 wt. %), teak wood content (20, 30 and 40 wt. %), and sawdust particle size (1.5–1, 1–0.85 and 0.85–0.6 mm). Multi-criteria decision-making (MCDM) analysis was employed to identify the optimal composite. The results indicated that the incorporation of teak wood significantly improved the flexural strength, with an increase of up to 94.6% compared to pure HDPE composites. However, the addition of polycarbonate generally had an adverse or negligible effect on tensile strength, elongation at break and impact resistance. Among the nine samples, Sample 1-containing 0 wt. % PC, 20 wt. % teak wood and 1.5–1 mm particle size-achieved the best overall mechanical performance, with a tensile strength of 31.83 MPa, a flexural strength of 45 MPa, an elongation at break of 18.3% and an impact resistance of 26.88 kJ/m². Overall, it was concluded that while teak wood is an effective reinforcement to enhance the flexural behaviour of HDPE-based WPCs, the addition of PC does not provide sufficient benefits and is economically unjustifiable under the studied conditions.

This study investigates the physical–mechanical behaviour of three tropical wood species Monopetalanthus heitzii (Andoung), Dacryodes buettneri (Ozigo), and Pterocarpus soyauxii (Padouk) commonly used for constructing footbridges, houses and exposed to weather conditions. The principal aim is to optimise their durability in structures by controlling, for example, their dimensional stability during changes in humidity. To rich this goal, species were prepared and analysed along with their transversal and longitudinal directions. Scanning electron microscopy revealed the internal cell arrangement of each species based on radial–tangential (R, T) and tangential–longitudinal (T, L) axis planes. Differential scanning calorimetry tests were conducted to assess thermal stability and degradation. Physical tests, focussing on swelling–shrinkage, were performed in a controlled chamber with constant temperature (T) and pressure (P). Parameters analysed included dimensions of the transversal plane (R, T) × (b, h) and the weight of each specimen. Additionally, compressive static tests were conducted to evaluate the mechanical behaviour of the specimens. The results indicate a correlation between intrinsic microscopic structures and macroscopic physico-mechanical behaviour. Furthermore, variations in water content were found to significantly impact the geometrical parameters of the specimens, particularly notable effects of drying and moistening on dimensional variations before the fibre saturation point (FSP).

This study focuses on the analysis of the price development of sawlogs of grade III quality A/B in the Czech Republic for the period 2005–2024 and on the prediction of their future development using the ARIMA model (1,1,1). The analysis of the historical data showed considerable price volatility, with the minimum value recorded in the third quarter of 2020 (CZK 1303/m³) and the maximum value in the third quarter of 2022 (CZK 3084/m³). The average price was CZK 1982/m³ with a standard deviation of CZK 1384.66/m³. The forecast shows a slight increase in prices until 2027, with projected values ranging between CZK 2377/ m³ and CZK 2457/m³. The weak negative correlation between price and quantity harvested indicates the influence of other factors such as global demand, seasonality and market regulation. The study provides evidence for strategic planning in the forestry and wood processing sector.

To implement the development concept of “lucid waters and lush mountains are invaluable assets”, China began to implement a ban on commercial logging of natural forests in 2015. The implementation of the ban has affected the structural adjustment of China's forestry industry. Based on the analysis of the internal relationship between the logging ban policy and industrial structure adjustment, this study uses the grey relational analysis method to explore the dynamic changes in China's forestry industry structure before and after the implementation of the natural forest logging ban policy and predict the development of China's forestry industry in the next 12 years through the GM (1, 1) model. Research shows that the implementation of the ban policy has the greatest impact on the development of the tertiary industry. The planting and collection of economic forest products have become an important industry in the primary industry, and enterprises are gradually shifting their focus to non-wood forests. Forest tourism and leisure services have become green and key industries with great growth potential in the forestry tertiary industry. In the future, China will maintain the industrial pattern of “two, one and three,” and the industrial structure will continue to be optimized.

This work investigates the feasibility to produce a new dry-process fibreboard (medium-density fiberboard, MDF) with pastel colours to be used in construction, furniture, interior claddings, interior design, shopfitting or artistic carpentry. The production of MDF coloured in the bulk with pastel colours is difficult due to the inherent brown colour of wood fibres. So, one of the key points of this study is to increase the fibre brightness using an innovative opacifying filler based on multi-hollow polyester particles as substitute of the common titanium dioxide (TiO₂). Fibreboards were produced with TiO₂ and multi-hollow particles (MHP) separately and combined with each other. The colour of panels was evaluated. Relevant properties of the produced boards were evaluated according to European Standards including density, internal bond, modulus of elasticity and bending strength. Boards produced with 10% of TiO₂ and with 5% and 7.5% of MHP incorporated satisfy the objectives in terms of colour and mechanical properties.

This study explores the viscoelastic behaviour of six tropical hardwood species from the Congo Basin: Azobé, Okan, Padouk, Sapelli, Fraké and Ayous, through dynamic mechanical analysis. These woods, commonly used in structural, furniture and outdoor applications, are subjected to thermal and mechanical stresses that significantly influence their long-term performance. Tests were carried out under controlled temperature and frequency conditions to evaluate the evolution of three key parameters: storage modulus (E′), loss modulus (E″) and loss factor (tan δ). Results reveal that the mechanical response of these materials is strongly dependent on temperature, frequency and wood density. Dense species such as Azobé and Okan exhibit higher stiffness and thermal stability, while lighter species like Fraké and Ayous show greater sensitivity to thermal softening and energy dissipation. The microstructural differences between species, such as cell wall thickness and porosity, are found to directly influence their viscoelastic properties. These findings highlight the need to consider both anatomical structure and operating conditions when selecting wood for applications exposed to varying thermal environments.