Mangium (Acacia mangium Willd.) is a fast-growing wood that is widely grown in Indonesia. The impregnation method is needed to improve the qualities of the wood. In this study, TiO₂ nanoparticle (79.17 nm) was produced using the hydrothermal method. The purpose of this study was to analyze the effect of TiO₂ nanoparticle impregnation on the density and dimensional stability of mangium and the effectiveness of the presence of TiO₂ nanoparticle in wood in degrading pollutants. The mangium samples (2 cm × 2 cm × 2 cm) were placed inside impregnation tube. The impregnation solutions included water (untreated), 1% TiO₂ nanoparticle, and 5% TiO₂ nanoparticles. The samples were analyzed for density, weight percent gain (WPG) dan bulking effect (BE). Samples were also analyzed by X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). TiO₂ nanoparticle resulted in an increase in density, WPG, and BE-treated mangium. Based on XRD and FTIR results, TiO₂ nanoparticle was successfully impregnated into mangium wood. Scanning electron microscopy–energy-dispersive X-ray spectroscopy analysis indicated that TiO₂ nanoparticle covered the surface of the wood cells. The TiO₂-impregnated mangium wood has a higher photocatalyst activity than untreated, indicating better protection from UV radiation and pollutants.

Jabon (Anthocephalus cadamba) is a fast-growing wood with low quality due to its low density and strength. The quality can be increased by modifying the wood through impregnation with various chemical compounds. In this study, jabon was impregnated with a solution of Fe and immersed in a strong base (NaOH) or a weak base (NH₄OH) to form magnetite (Fe₃O₄) in-situ. This study analysed the use of NaOH and NH₄OH in synthesising magnetic jabon wood and evaluated the wood’s characteristics. The impregnation process began with a vacuum of −0.5 bar for 0.5 h and then a pressure of 1 bar for 2 h. The samples subsequently underwent assessment of their dimensional stability, density, and characteristics. The results showed that impregnation with Fe solution followed by NaOH or NH₄OH significantly affected the density and dimensional stability of the wood. The polymer weight gain was higher with NaOH, while the anti-swelling efficiency was higher with NH₄OH. The density and bulking effect were increased, but the water uptake was decreased. Fourier transform infrared analysis showed the successful synthesis of magnetite. Scanning electron microscopy–energy-dispersive X-ray spectroscopy analysis revealed that magnetite covered the vessel fibre cell walls, and vibrating sample magnetometry analysis showed significant magnetic properties of the wood.

Sengon (Falcataria moluccana Miq.) is one of the fastest growing wood that is broadly planted in Indonesia. Sengon wood has inferior wood properties, such as a low density and dimensional stability. Therefore, sengon wood requires a method to improve its wood quality through wood modification. One type of wood modification is wood impregnation. On the other hand, Betung Bamboo leaves are considered as waste. Betung Bamboo leaves contain silica. Based on several researches, nano-SiO₂ could improve fast-growing wood qualities. According to its perfect solubility in water, monoethylene glycol (MEG) is used in the study. The objectives are to evaluate the impregnation treatment (MEG and nano-silica originated from betung bamboo leaves) in regard to the dimensional stability and density of 5-year-old sengon wood and to characterize the treated sengon wood. MEG, MNano-Silica 0.5%, MNano-Silica 0.75%, and MNano-Silica 1% were used as impregnation solutions. The impregnation method was started with 0.5 bar of vacuum for 60 min, followed by 2.5 bar of pressure for 120 min. The dimensional stability, density, and characterization of the samples were studied through the use of scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The results show that the treatment had a significant effect on the dimensional stability and density of sengon wood. Alterations in the morphology of treated sengon wood were observed through the full coverage of the pits on the vessel walls (SEM analysis results) and the detection of ethylene (FTIR analysis results) and silica (XRD and FTIR analysis results). Overall, the 0.75% MNano-Silica treatment was the most optimal treatment for increasing the dimensional stability and density of 5-year-old sengon wood.

Acacia mangium requires the addition of a finishing material to increase its resistance to weathering. Herein, the effectiveness of a nanocoating containing titanium dioxide nanoparticles (TiO₂-NPs) as a finishing material for mangium wood was investigated. The coating material formulations used were oil-based (V1) and water-based (V2) varnishes with TiO₂-NP concentrations of 1% (CT1), 5% (CT5), and 10% (CT10) (w/v). The uncoated and coated samples were subjected to weathering periods of 0, 2, and 4 months. The results showed that the addition of TiO₂ nanoparticles to the V1 and V2 varnishes resulted in more gradual colour changes after the weathering period. The surface of the mangium wood also became smoother after being coated. However, the surface roughness increased with the duration of the weathering period. The wettability (K-value) of the sample decreased after coating, indicating that the coated sample was more hydrophobic than the uncoated sample. The results of a photocatalyst test, which analysed the effectiveness of the coatings, showed that the best coating material formulas were V1-CT10 and V2-CT10, as they degraded 75.21% and 71.03% of methylene blue content, respectively. Fourier transform infrared analysis showed that mangium wood did not undergo rapid weathering after the nanocoating treatment, as indicated by an insignificant decrease in the peak absorption intensity of the main structural functional groups of wood.

Fast-growing wood is rarely used by the community because of its low quality. This study aimed to modify the sengon (Falcataria moluccana) and jabon (Anthocephalus cadamba) into magnetic wood so they have new functions. In this study, the modification process was performed by impregnating five-level concentrations of Fe₃O₄ nanoparticles dissolved in two different dispersants, namely water and a mixture of furfuryl alcohol and water. The impregnation process is initiated by a vacuum of -0.5 bar, followed by a pressure of 1 bar for 120 min. The addition of furfuryl alcohol to the impregnation solution significantly increased the physical properties of magnetic wood. The presence of Fe₃O₄ in wood is also proven by the Fe-O groups observed from the FTIR spectrum analysis. The magnetic field strength also increased as the concentration level of Fe₃O₄ increased. Based on the results of this research, the best treatment was obtained on magnetic wood of sengon and jabon with furfuryl alcohol and Fe₃O₄ nanoparticles concentration of 7.5%. Keywords: Fast-growing wood, impregnation, magnetic wood, nanoparticles, nano Fe3O4

The impregnation process is carried out to increase the resistance of wood from the attack of microorganisms such as fungi and termite attacks by placing the wood in a vacuum tube and then placing an impregnan solution into it. The limited ability of impregnation tubes is an obstacle in carrying out research and practicum activities, therefore there needs to be modifications to the impregnation tube so that the impregnation process can provide better results. Verification of the results of impregnation is done by calculating the value of weight percent gain (WPG) and relative standard deviation (%RSD) for the test of the level of appreciation. Based on the results of the experiment the highest %WPG value in the water impregnan solution was obtained from the parameter conditions of the type 3 press vacuum tool, which is with a time of 1 hour and a pressure of 5 bars and is worth (178.29±10.97). The highest %WPG value in boron solution of 5% is obtained from the condition of the type 6 press vacuum tool with a time of 3 hours and a pressure of 5 bars and is worth (5.16±0.45). The smallest %RSD value of water impregnan solution is achieved under the parameter conditions of type 4 tools at 3 hours and pressure 1 bar and is worth 3.99%. The smallest %RSD value of boron impregnan solution is 5% achieved under the parameter conditions of type 2 tools, namely within 1 hour and pressure of 3 bars and is worth 5.36%.