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In the near future, wood demand will be fulfilled by local fast growing woods from community forest. Among those, samama (Anthocephalus macrophyllus) is an endemic wood in Celebes and Moluccas. This species has been cultivated throughout Indonesia and usually harvested at age of less than 10 years. This research was conducted to examine the quality of samama wood at 8 and 10 years old. Each age group was represented by three healthy trees. Samples were made from 1 cm segmentation from pith to bark. Modified exponential curve was used to determine the transition of juvenile and mature wood in which maturity limit was achieved when growth parameter had reached the asymptote line. The quality parameters were specific gravity, moisture content, fiber length, fiber wall thickness and microfibril angle. The result showed that the first 6-8 segmentations from the pith were still juvenile, while the subsequent segments were mature wood. The 8 years old had 33.3-38.9 % of juvenile portion, while it was only 30.4-34.8 % in the 10 years old. This finding will be important in considering a proper technology for samama wood processing.

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Relatively little information is available regarding the correlation between wood and veneer quality, especially for Samama wood, an endemic wood species in eastern Indonesia. This study addresses the quality of 8 years old Samama wood and its effect on the veneer quality. Samama wood quality was determined by evaluating its specific gravity, moisture content, fiber dimensions, and microfibril angle from pith toward bark. Meanwhile, veneer quality was assessed by examining veneer thickness and lathe check characteristics. Geometry factor model was constructed to elaborate the quantities of lathe check from pith toward bark. Results show that fair variations of veneer thickness, ranging from 1.5 mm to 3.0 mm, could be obtained from Samama wood. The quantity, depth, and length of lathe check were noticeably decreasing toward bark. Further, in the same manufacturing process, geometry factor was determined as the dominant factor over other wood properties in affecting the frequency of lathe checks from pith towards bark. These facts should be put into consideration in producing veneer from Samama wood. Moreover, these results enlighten the potential of Samama wood as plywood and other excellent veneer-based products.

Boron compound had many advantages as wood preservative, but it was prone to leaching. Improving boron preservation was required to extend the service life of fast growing and low durability red jabon (Antochephalus macrophyllus) hardwood. This study aimed to evaluate the dimensional stability, color change and durability of modified red jabon wood by double impregnation with boron and methyl methacrylate (MMA) and heat treatment. Impregnation I used boric acid or borax, and impregnation II used MMA, while heat treatment used temperatures of 90 °C or 180 °C for 4 hours. The dimensional stability, leachability, water absorption, color change and decay resistance of modified red jabon wood were tested. The results showed that MMA impregnation increased the dimensional stability of red jabon wood, while the leaching and water absorption in the wood significantly reduced. Heating at 180 °C caused less water absorption and higher dimensional stability of the wood than that of heating at 90 °C. Impregnation with boric acid and MMA followed by heating at 90 °C resulted in the highest wood ASE, 89.9%. The color change (∆E * ) of wood increased significantly after MMA impregnation and heating at 180 °C. Boric acid impregnation caused more resistant wood than borax impregnation against decay fungi and termites. Impregnation with boric acid and MMA followed with heating at 180 °C increased significantly the wood resistance against decay fungi and termites.

Abstrak Sudut kontak dan keterbasahan dinamis penting diketahui untuk menganalisis keteguhan rekat. Penelitian ini bertujuan mengetahui sudut kontak dan keterbasahan dinamis kayu

Red jabon wood is a potential fast-growing species for veneer, furniture, and many other wood products, but its durability is very low. The purpose of this study was to investigate the effects of castor bean oil and heating on boron leaching, dimensional stability, and resistance to decay fungi in treated jabon wood. Red jabon wood was preserved with boron solutions containing 5% boron (boric acid, borax, or borax-boric acid). Following that, castor bean oil impregnation and heating were used as posttreatments. Furthermore, all the wood samples were tested in terms of leaching, dimensional stability, and resistance against Schizophyllum commune and Fomitopsis palustris fungi. This study discovered that boron compounds, castor bean oil, and heating treatments influenced the leaching, dimensional stability, and resistance of red jabon wood to decay fungi. The double impregnation of boric acid or borax and castor bean oil, followed by heating at 160℃, significantly reduced water absorption and leaching while increasing the dimensional stability and resistance of red jabon wood against the two tested decay fungi.

Citric acid’s potency to be adhesive is proven with an increasing quality of product bonding resulted from wood and other lignosellulosic materials. Wood waste, bagasse, sorghum and corn stalks, and bamboo are quality particleboard materials after addition of 20% citric acid. Moulding made of a mixture of tree bark and citric acid with the same concentration is also able to pass repeated boiling test without having any damage. Ester bond between wood’s hydroxyl group and citric acid’s hydroxyl group is formed at 180ºC and gets more optimal as the pressing temperature increases during production process. This results in an increase of board’s physical-mechanical properties pursuant to the standard. Some researches remain presenting non-standard test parameters and this is a challenge to be answered with further research. The density of Samama wood impregnated with 10% citric acid has its density increased between 17.11% and 20.13%. Samama wood does not experience a recovery of set after it has been pressed for 50 minutes at 180°C.