< 구두-E-06 > Performance of LVL samama (Anthocephalus macrophyllus) based on thickness, juvenile proportion and veneer lay-up

( Tekat Dwi Cahyono ),( Wayan Darmawan ),( Eka Novriyanti ) 한국목재공학회 2018 한국목재공학회 학술발표논문집 Vol.2018 No.1

A study to determine the quality of laminated veneer lumber (LVL) from samama wood (Anthocephalus macrophyllus) was carried out. Samama is a fast growing endemic wood in the eastern Indonesia. Factorial of 3 factors in RAL design was used to investigate the influence of veneer thickness, juvenile proportion and veneer lay-up to the quality of the resulted LVL samama. The veneer thicknesses were 1.5 mm and 3.0 mm. Juvenile proportions were arranged in 5 levels which were 100% of juvenile veneer, 100% of mature veneer, and combination of both juvenile and mature with juvenile proportion of 14%, 43% and 71%. Two veneer lay-up used in this study were loose side met loose side and tight side met loose side. The result of the study showed the vary density of LVL by the different proportion of juvenile and veneer thickness. This factor also affected the other physical traits. Shear strength of the LVL was equal with the wood, yet MOE and MOR were affected by juvenile proportion and veneer lay-up. LVL developed from 100% of mature veneer gave the best mark of MOE and MOR, although there was no significant difference in quality with the other tested juvenile proportions.

Linear Expansion and Durability of a Composite Boards (MDF Laminated Using Three Selected Wood Veneers) against Drywood Termites

( Tekat Dwi Cahyono ),( Hikma Yanti ),( Laela Nur Anisah ),( Muh Yusram Massijaya ),( Apri Heri Iswanto ) 한국목재공학회 2020 목재공학 Vol.48 No.6

This research was conducted to investigate the linear expansion and resistance properties of a composite board (com-ply). This board was made of medium-density fiberboard (MDF) laminated using avocado (Persea americana), mahogany (Swietenia mahogani), and pine (Pinus merkusii) veneers. These three types of veneers were laminated on both surfaces of the MDF using adhesives, namely, epoxy and isocyanate. Glue (250 g・m^-2) was spread on the surface, followed by cold press for 3 h with an applied pressure of 15 kg・cm^-2. The research result revealed that com-ply exhibited an increased dimensional stability compared with MDF, indicated by reduction in water absorption, thickness swelling, and linear expansion. The com-ply made of the pine veneer and isocyanate adhesive exhibited high density, water absorption, thickness swelling, and screw withdrawal load. The com-ply that exhibited the strongest resistance to drywood termite attacks was the one made of the mahogany veneer and isocyanate adhesive. Moreover, the com-ply that exhibited the biggest weight loss (3.6 %) was made of the pine veneer and epoxy adhesive. The results of this research may facilitate in manufacturing com-ply using the selected veneer and adhesive without the application of hot press.

Flexural Properties of Heat-Treatment Samama (Anthocephalus macrophyllus) Wood Impregnated by Boron and Methyl Metacrylate

( Tekat Dwi Cahyono ),( Wayan Darmawan ),( Trisna Priadi ),( Apri Heri Iswanto ) 한국목재공학회 2020 목재공학 Vol.48 No.1

This study was conducted to analyze the application of boron compounds, methyl methacrylate (MMA), and heat treatment (HT) on changes in the density, moisture content, and flexural properties of samama (Anthocephalus macrophyllus) wood. Samama wood was impregnated with borax (BX) and boric acid (BA) using a pressure method at 5 atm for 4 h. Afterwards, the wood was impregnated with MMA at the same pressure and duration. Finally, the samama wood was given HT at 90 ºC and 180 ºC. The results indicate that there was a weight gain of 93.4% in the wood impregnated using BA and MMA monomer and HT at 90 °C. Consequently, the wood’s density increased by 82.3%. Increased MOE and MOR percentages of 32.2% and 29.4%, respectively, were also found. HT at 180 °C degraded the wood components and MMA, and consequently, the density, MOE, and MOR also decreased. The wood impregnated by BX, BA, and MMA, and subjected to HT also had decreased moisture content (MC). This research recommends that the application of boron (BX, BA) should be combined with an MMA monomer and HT at 90 °C as an alternative method to improve samama wood quality. If darker color is preferable, HT should be conducted at 180 °C.

Dimensional Stability, Color Change, and Durability of Boron-MMA Treated Red Jabon (Antochephalus macrophyllus) Wood

( Trisna Priadi ),( Gema Orfian ),( Tekat Dwi Cahyono ),( Apri Heri Iswanto ) 한국목재공학회 2020 목재공학 Vol.48 No.3

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 (ΔE*) 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.

Posttreatment Effects of Castor Bean Oil and Heating in Treated Jabon Wood on Boron Leaching, Dimensional Stability, and Decay Fungi Inhibition

( Trisna Priadi ),( Marini Dwi Lestari ),( Tekat Dwi Cahyono ) 한국목재공학회 2021 목재공학 Vol.49 No.6

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.

Fundamental Properties of Composite Board Made with Oriented Strand Board and Three Different Species of Veneer

( Hikma Yanti ),( Muh Yusram Massijaya ),( Tekat Dwi Cahyono ),( Eka Novriyanti ),( Apri Heri Iswanto ) 한국목재공학회 2019 목재공학 Vol.47 No.2

This research presents an improvement of the physical and mechanical properties of composite board (com-ply) made of Oriented Strand Board (OSB) coated with wood veneer of Pine (Pinus merkusii), Avocado (Persea Americana) and Mahogany (Swietenia mahogany). 1.5 mm thick veneers of those three wood types were adhered to the surface of OSB using two adhesive types: epoxy and isocyanate. The adhesive with the glue spread of 250 g m^-2 applied using single glue line was spread and then cold pressed with the pressure of 15 kg cm^-2 for 3 hours. The research result showed an improving dimension stability of com-ply, but not found on all parameters of physical property test. The moisture content seemed to be influenced by the com-ply type, yet not related to its thickness swelling, water absorption and linear expansion. The exception took place in the parallel linear expansion when immersed for 2 hours. The highest to the lowest increases of MOE and MOR were consecutively found on OSB coated with wood veneer of Pine, Mahogany and Avocado. However, the increases were statistically insignificant. The highest increasing screw hold power was found at the com-ply type AE (avocado veneer and epoxy adhesive) that was by 28%.

Reliability of the Impregnated Boron Compounds, Citric Acid- and Heat-Treated Samama (Anthocephalus macrophyllus) Wood against the Fungal and Termite Attacks

Trisna PRIADI,Guruh Sukarno PUTRA,Tekat Dwi Cahyono 한국목재공학회 2023 목재공학 Vol.51 No.1

This research aimed to evaluate the durability of Samama (Anthocephalus macrophyllus) wood treated with boron preservatives, citric acid (CA), and heating against termites. Wood samples were impregnated firstly with 5% boron solutions, such as boric acid, borax and boric acid + borax combination at 1:1 (w/w). The second impregnation used 5% CA. The impregnations were conducted in a pressure tank at 7 kg/cm2 for 4 hours. After impregnation, the samples were heat treated at 80℃ or 160℃. All the treated and control samples were exposed to decay fungi, drywood termites and subterranean termites based on SNI 7207:2014 standard. The results showed that boron preservatives reduced fungal attacks on Samama wood. The combination treatment of boric acid, CA and heat treatment at 160℃ was also effective to increase the resistance of Samama wood against white- and brown rot fungi, and drywood termites. Heat treatment consistently improved the resistance of Samama wood from decay fungi.