This study aimed to assess the effectiveness of large-scale heat treatment on Moso bamboo (Phyllostachys pubescens) grown in South Korea. The process involved multiple stages, including pretreatment, boiling, steaming, heating, and cooling. Heat treatment successfully reduced the water content to below 3% and increased the specific gravity from 0.62 to 1.12, thereby enhancing dimensional stability and strength. Following an ultraviolet-accelerated weathering test, the heated Moso bamboo exhibited improved color stability (ΔE 5.84) compared to untreated bamboo (ΔE 9.92). Furthermore, the heat-treated bamboo demonstrated high resistance against wood-rot fungi (weight loss < 10%) and termites (weight loss approximately 2%). In contrast to small lab-scale drying processes, this study employed a pilot-scale kiln for mass production, resulting in large-sized Moso bamboo with enhanced properties. This study revealed that distinct results, including extractives and lignin-degraded compounds, persisted in heated Moso bamboo cells after the heat treatment. The overall improvement in deterioration resistance, achieved through heat treatment, significantly contributes to the durability and longevity of bamboo materials in outdoor settings, such as landscape facilities.

Paulownia tomentosa, a tree species that allows for efficient production of translucent wood, was selected as an experimental wood species in this study, and a two-step process of delignification and polymer impregnation was performed. For delignification, 2–4 mm thick specimens were immersed in peracetic acid for 8 h. The delignified-wood specimens were impregnated using epoxy, a commercial transparent polymer. To identify the characteristics of the resulting translucent wood, the transmittance and haze of each type of wood section (cross- and tangential) were measured, while bending strength was measured using a universal testing machine. The translucent wood varied in properties according to the wood section, and the total transmittance and haze were 88.0% and 78.5% for the tangential section and 91.3% and 96.2% for the cross-section, respectively. For the bending strength, untreated wood showed values of approximately 4613.5 MPa modulus of elasticity (MOE), while the epoxy impregnation to improve the strength of the wood had increased the MOE up to approximately 6089.9 MPa, respectively. A comparative analysis was performed in this study with respect to the substitution of balsa, which is used widely in the production of translucent wood. The results are anticipated to serve as baseline data for the functionalization of translucent wood.

Paulownia tomentosa is a representative deciduous tree in South Korea. After 10 years of growth, its wood can be used to make various products through chemical modifications, such as impregnation with a polymer, substitution with chemicals, and physical compression. However, research on the biological resistance of the sapwood and heartwood parts of P. tomentosa xylem is lacking. To ensure the complete utilisation of Paulownia wood, this study aimed to collect baseline data on the necessity of xylem extraction before chemical modification to enhance wood porosity. First, we assessed the decay and termite resistance of sapwood and heartwood blocks. Furthermore, we evaluated the anti-microbial effect of sapwood and heartwood extracts after solvent fractionation. Quantitative and qualitative analyses of the active substances of the fractions with anti-microbial activity were also conducted. The hexane and chloroform solvent fractions of sapwood and heartwood extracts showed fungal resistance against Trametes versicolor and Fomiptosis palustis. Paulownin and sesamin were the main compounds showing anti-microbial activity, and their content in the extracts varied, depending on the wood part. These results provide valuable data for advancing research on porous wood materials and the utilisation of xylem-derived active compounds from Paulownia wood.