Research Articles

Lignin-based adhesives are promising eco-friendly alternatives to petroleum-derived resins, but they face challenges in bonding strength and water resistance. This study presents a dual chemical modification strategy—phenolation and hydroxymethylation—to enhance the reactivity and polarity of industrial lignin. The modified lignin was blended with polyvinyl alcohol (PVOH) and epoxy resin to formulate adhesives suitable for engineered wood applications. Among the tested formulations, the PVOH-lignin adhesive reached a tensile shear strength of 7.8 MPa with 85% strength retention after water immersion, while the epoxy-lignin adhesive achieved 9.5 MPa with enhanced thermal resistance. Structural characterization using FTIR and 1H-NMR confirmed the successful introduction of functional groups. To reduce energy consumption, a low-temperature and low-pressure curing process based on microwave-assisted heating and mechanical stirring was implemented, reducing energy use by 40% compared to conventional heating methods. Life cycle assessment (LCA) results indicated a 40% lower carbon footprint and 50% reduction in volatile organic compound (VOC) emissions relative to petroleum-based adhesives. These results demonstrate the feasibility of using chemically modified lignin in high-performance adhesive systems for engineered wood while improving environmental sustainability.

The inlaying of molten metal into artificial or natural wood cracks represents an innovative combination of metal and wood. After cooling and solidifying, a unique texture is formed, offering a rich aesthetic experience rooted in its intricate decorative texture. This study systematically summarizes the process steps of molten metal inlaid in wood, including material selection, pretreatment, casting, cooling, and sanding. It elaborates on the aesthetic characteristics and decorative potential of this novel material through three aspects, including visual expression, tactile difference, and cultural value. Selected design cases of molten metal inlaid in wood for home furnishings are analyzed to assess the product design feasibility through the lens of craft aesthetics. The research further provides a guiding direction for its design application in household products.

The aim of this study was to investigate the effects of different doses and application methods of Trinexapac-ethyl (TE) and Paclobutrazol (PAC) on the growth, development, and flowering characteristics of safflower (Carthamus tinctorius L.) plants. This study will contribute to revealing and expanding the potential of this species, which is known to have high drought, cold, and salinity tolerance, in the ornamental plants sector. In the experiment, two safflower cultivars (Olas and Dinçer), two different plant growth inhibitors (TE and PAC), two different application methods (foliar and soil), and different doses (TE: foliar- 0, 4, 6, 8, and 12 ppm; PAC: soil- 0, 25, and 50 mg/pot, foliar- 0, 50, 100, and 500 ppm) were studied. Based on the results obtained, the use of TE and PAC, which are plant growth inhibitors, is seen as a suitable alternative to use ‘Olas’ and ‘Dinçer’ cultivars of safflower plant as ornamental plants in landscape designs and to expand their use for this purpose. It was determined that PAC application at a dose of 500 ppm in the form of foliar spray was an appropriate application especially in terms of suppressing height growth, and the plants treated with TE had a wider plant width compared to those treated with PAC.

Softness is a critical yet subjective characteristic of hygiene paper products such as facial tissues. In this study, softness values were obtained from the authors’ previous research using the Interval Scale Value (ISV) method, involving panelists’ round-robin pairwise comparisons. A machine-learning approach was developed to predict softness from one-dimensional power spectral density (1D-PSD) spectra of surface roughness profiles. Using seven commercial samples and an optimized multilayer perceptron model, a achieved high predictive performance (R² = 0.860) was achieved without additional measurements such as tensile modulus or surface friction. This work highlights the potential of combining spectral analysis and machine learning for objective softness evaluation.

Corn husk, a significant by-product of the corn deep-processing industry, is currently utilized as coarse feed, yielding very low economic benefits while consuming high amounts of energy and water. This study focused on the high-value utilization of corn husk resources. A two-step enzymatic hydrolysis and combined microbial fermentation was adopted to produce corn husk microbial protein feed. The true protein content was increased by 103% through yeast proliferation. To explore the key driving factors affecting yeast proliferation, a quantitative polymerase chain reaction (qPCR) was adopted to analyze the succession of yeast communities during the fermentation of corn husks. Redundancy analysis (RDA) and variance inflation factor (VIF) were applied to examine the relationship between physicochemical factors and yeast microbial community. The results revealed that, in terms of fermentation time, the uppermost driving factors influencing yeast abundance is moisture content; in terms of contribution, both cellulose content and moisture content serve as the most significant driving factors for yeast proliferation. This research revealed that microbial-enzyme synergy can significantly increase the true protein content of feed, and the key driving factors identified further provide theoretical references for the controllable yeast fermentation.

As people pay more attention to environmental issues, incorporating leather elements in solid wood furniture has become a new trend. This change reflects consumers’ concern for sustainable materials and their quest for personalized home design. Due to the similarity between styling of leather custom closets in the market, its surface texture and color are the key factors influencing consumers’ purchasing decisions. This study explored the visual-tactile perception of different leather materials by Chinese leather custom furniture consumers and establish an evaluation model. Based on Kansei engineering and market trend research, 12 representative leather samples and 7 perceptual phrases were selected through expert evaluation and KJ methods. Questionnaires were used to collect consumers’ visual-tactile perception evaluations of leather samples. Analysis using SPSS software showed that surface roughness, softness, and comfort of the material were the key factors affecting the tactile perception, while the visual perception was closely related to the color characteristics and aesthetic of the material. Cluster analysis categorized these materials as suitable for 4 different styles of home environments. This paper provides a theoretical basis for selecting materials for leather customized furniture and guides future design.

Hornbeam (Carpinus betulus L.) wood often has a spiral grain character, which contributes to shape instability in the resulting products. Spiral grain refers to the deviation of wood fibers from the longitudinal axis. This study identified and quantified specific shape changes caused by spiral grain in hornbeam samples. Differences between samples were analyzed with varying degrees of spiral grain and their impact on the shape stability of hornbeam lumber. Changes in the warp cup and the warp twist were monitored during three months of an air-drying process. Moisture loss was found to have a significant influence on the increase in the observed types of warps. An average rise in warp cup from 0 mm to 0.61 mm was recorded in specimens lacking spiral grain, whereas in specimens exhibiting spiral grain, it was raised from 0 mm to 0.92 mm over the same period. Warp twist was increased from a mean value of 7.2 mm in non-spiral-grain specimens to 19.6 mm in spiral-grain specimens. Moreover, the original position of the lumber pieces within the logs whether adjacent to the pith or the bark was determined to be a significant factor in the final type and size of the warp (curvature). This study highlights the critical role of spiral grain and log positioning in shaping the dimensional stability of hornbeam lumber during drying.

Pyramid-type and lattice-type sandwich structure plate members were designed and fabricated using oriented strand board as the panel and larch finger-joined lumber as the core material, while glass fiber was used as the panel reinforcing material. The mechanical properties of the four types of sandwich structure plate members were tested by four-point bending test. The test results showed that the damage forms of the plate members were mainly the debonding between the core and the panel and the bending failure of the core. It can be concluded from the mechanical properties of plate members with sandwich structure that the transfer path and efficiency between the panel and the core layer of a sandwich structure plate members have a decisive influence on the flexural performance of the specimen. The core configuration determines the relative stiffness ratio between the panel and the core. This study was able to provide reliable experimental data and theoretical support for the application of wood-based sandwich structure plate members in prefabricated temporary buildings, landscape timber structures, and other fields, in order to promote their optimized design and wide application.

Dehydrogenation polymer (DHP) was synthesized by free radical coupling dehydrogenation polymerization of the lignin precursor coniferin under the catalysis of various enzymes. DHP has a highly similar connection structure to natural lignin (such as β-O-4, β-β, β-5, etc.), so it shows the potential as a new zero formaldehyde release adhesive. In plants, a very stable lignin-carbohydrate complex (LCC) is formed between lignin and cellulose and hemicellulose, which makes plants have excellent mechanical strength. In this paper, the thermal condensation reaction between DHP and D-glucose-¹³C₆ was simulated by hot pressing of wood-based panels, and the DHP-D-glucose-¹³C₆ complex was prepared. The condensation was analyzed by Fourier Transform Infrared (FTIR) and nuclear magnetic response (NMR) characterization. The signals of C₁ and C₆ of glucose in the complex could be clearly observed in the FTIR and NMR spectra, which showed that DHP and D-glucose-¹³C₆ can undergo thermal condensation reaction in the simulated hot-pressing environment. The C₁ on the glucose unit may form a C-C bond with the C₆ on the aromatic ring in DHP. It was found that DHP can function as a formaldehyde-free wood-based panel adhesive, thereby providing new evidence about the mechanism of adhesion within plant fibers.

The study of surface properties—particularly wettability—and how these vary from pith to bark in relation to changes in surface roughness, chemical composition and crystallinity is of importance to improve the use of wood that comes from thinning of a hardwood plantation. In this study, water wettability was assessed by measuring the contact angle using a drop shape analyzer, while surface roughness was evaluated with a confocal microscope. The chemical composition and crystallinity of the surface were analyzed using Fourier Transform Infrared Spectroscopy (FT-IR). To minimize the influence of machining variables on surface properties, a consistent surface quality before and after thermal modification was ensured using computer-controlled cutting. The results revealed that, prior to thermal modification, the contact angle varied significantly from pith to bark. After modification, the contact angle increased, but the differences were no longer statistically significant, due to the homogenization of the chemical-structural characteristics caused by the thermal modification. Relative crystallinity and surface roughness tended to increase towards the bark, with the contact angle tending to decrease, before and after modification.