BASIC PROPERTIES OF SENTANG WOOD (Melia excelsa Jack) AND ITS SUITABILITY AS ORIENTED STRAND BOARD MATERIALS

Tujuan penelitian ini adalah untuk melihat kesesuaian kayu sentang sebagai bahan baku berdasarkan tinjauan sifat dasarnya dalam hal ini anatomi, fisis, dan kimia. Metode yang digunakan dalam penentuan struktur kayu yaitu teknik maserasi dan mikrotom, sifat fisik berdasarkan standar BS-373 (1957), dan sifat kimia menggunakan standar TAPPI. Hasil penelitian menunjukkan bahwa (1) struktur kayu: kayu sentang cocok dipergunakan sebagai bahan baku OSB karena memiliki dinding sel tipis sampai sedang, pori relatif banyak. Ini merupakan dua faktor yang berperan penting dalam hal perekatan dan proses pengempaan; (2) sifat fisik: kayu sentang memiliki BJ sedang, nilai T/R untuk kering udara dan oven masing-masing 1,25 and 1,17; serta (3) sifat kimia: kayu sentang memiliki kandungan ekstraktif sedang, kandungan selulosa tinggi dan lignin dan kadar abu sedang. Kata kunci: kayu sentang, struktur kayu, fisis, kimi

Polygon sawing : an optimum sawing pattern for oil palm stems.

The shortage in wood supply makes the effort to find alternative for wood material become more and more important. It was reported that the outer parts of oil palm stems could be used as solid wood after being properly treated. Being a monocotyledon, oil palm stems have a contradictory characteristic to the conventional hardwoods and softwoods and thus the sawing patterns suitable for hardwoods and softwoods should not be suitable for the oil palm stems. Two modified sawing patterns (polygon sawing and cobweb sawing) plus one ordinary sawing pattern (life sawing) were compared in the sawing of oil palm stems. The purpose of this study was to find the most suitable sawing pattern for oil palm stems. The cobweb sawing provided the highest outer lumber recovery (35%) followed by polygon sawing (27%) and life sawing (23%). The polygon sawing provided the highest occurrence of wide lumbers, followed by the cobweb sawing and life sawing. The cobweb sawing need more than twice effective sawing time (15.4 min) than the life sawing and polygon sawing. In overall, the polygon sawing was the most suitable pattern for the sawing of oil palm stem

Effects on Morphology and Chemical Properties of Indonesian Bamboos by Carbonization

A simple carbonization technique was applied to utilize Indonesian bamboo resources. Several bamboo species as betung (Dendrocalamus asper), andong (Gigantochloa pseudoarundinacea (Steudel) Widjaja), hitam (G. atroviolacea), tali (G. apus), kuning (Bambusa vulgaris var. striata), and ampel bamboo (B. Vulgaris Scharad) were selected for carbonization. Carbonization was conducted using a laboratory electrical furnace at 200, 400, 600, 800, and 1,000 1,000°C. The morphological and chemical properties of bamboos before and after carbonization were then analyzed. Betung, hitam, tali, kuning, and ampel bamboos had type IVstructure which was the most common bamboo structure, while andong bambo had type III structure. Cracks in the fiber bundle were observed and became more visible with the increase of carbonization temperature.The pH showed a similar trend in all species.As a result of the electric conductivity test, carbonized andong and kuning bamboo showed higher value due to rich inorganic content.Kuning bamboo has a high value of potassium and silica content, which are suitable for use as fertilizer.The chemical structure transition of bamboo during the carbonization process was analyzed by FTIR spectroscopy, and significant changes were observed between 400 and 600°C. These results could be useful fundamental data for promoting high value-added bamboo utilization and improving research in Indonesian bamboo.Keywords: bamboo charcoal, carbonization, Indonesian bamboo, inorganic content, FTI

Influence of wood flour and modifier contents on the physical and mechanical properties of wood flour-recycle polypropylene composites

The objectives of this research was to evaluate the physical and mechanical properties of composites of Wood Flour (WF) and Recycle Polypropylene (RPP) prepared under various WF contents, WF sizes and modifier contents. WF from mixed-soft wood species and Eucalyptus deglupta Blume species were used as filler. The composites composed of 0-70% WF, 0-70% Polypropylene (PP) or RPP, various sizes of WF (60-80; 80-100 and < 120 mesh), various contents of MAH modifier (0, 1, 2.5, 5, 7.5 and 10%) and 15% Dicumyl Peroxide (DCP) initiator (based on MAH weight). Kneading conditions were set at 170 °C, 10-50 rpm for 15 min. The physical and mechanical properties of composites were greatly affected by WF content, WF size and modifier content. The greater the WF loading resulted in the greater was the reduction of tensile strength and breaking elongation values and at the same time the greater was the increasing of Young`s modulus value. The smaller the WF size resulted in the greater the tensile strength of composites. Addition of MAH modifier improved the physical and mechanical properties of composites. WF-RPP composites with 120 mesh WF size and 2.5% MA modifier had tensile strength, breaking elongation and Young`s modulus about 2.15, 2.27 and 1.18 times, respectively higher compared with composites free-MAH modifier and absorbed considerably less water. Scanning Electron Microscope (SEM) indicated that addition of MAH improved the adhesion between WF and RPP

Binderless MDF from Hydroxymethylated Kenaf Pulp

Modified lignin with improved reactivity can be a potential alternative for synthetic phenol formaldehyde resin for the adhesive of wood composite. Direct hydroxymethylation of kenaf in the present experiments was intended to increase lignin reactivity, and therefore was expected to result in satisfying properties of binderless MDF. The stem of kenaf was refined in a disk refiner and the refined fibers were hydroxymethylated in various levels of alkalinity. The concentration of NaOH during hydroxymethylation was of 3%, 6% and 12%. Wet process was applied to produce MDF (30 cm x 30 cm x 1 cm) with target density of 0.65 g/cm³. Physical and mechanical properties of MDF were measured in accordance with the standard procedure of JIS A 5905: 2003. Chemical changes in the surface of pulp and the change of board crystallinity were evaluated by FTIR-KBr method and X-Ray Diffractometry (XRD), respectively. Density, moisture content, and screw withdrawal of the board increased with increasing of NaOH concentration. Thickness swelling, water absorption, MOE and MOR increased up to 3% concentration of NaOH. The IB and heat conductivity of MDF were not influenced by NaOH concentration. Increasing OH groups due to hydroxymethylation was thought to be the origin of high water absorption and thickness swelling of the resulting boards. Higher alkalinity during hydroxymethylation stage was likely increasing cellulose crystallinity that brought about increasing board density. However, chemical modification of the fiber was thought to be more influential to the bending strength and stiffness of the resulting fiberboard. Hydroxymethylation of kenaf pulp was successfully improved board properties. Except for the moisture content, thickness swelling and internal bonding (at 0% and 3% NaOH concentration), all properties of the MDF satisfied the requirement of JIS A 5905: 2003 (type 5) standard

The Quality Of Composite Board Made Of Waste Oil Palm Stem (Elaeis Guineensis Jacq) And Recycle Polyethylene (Pe)

The main objective of this research was to find out the substitution of solid wood and it may solve environmental problem. These researches concerned on using waste of oil palm stem particle form and recycle plastic polyetyhlene (PE) as raw materials for composite board. In this research, 5% Maleic Anhydride (MAH) was added to increase compatibility and 0.75% Dicumyl Peroxide (DCP) was added to initiate the reaction of maleolation. The methods of this research followed JIS A 5908 (2003) with ratio of plastic to particle were 50:50, 60:40 and 70:30, respectively, pressed at 30 kgf/cm2 in 165°C for 15 minutes. Evaluation on physical and mechanical properties based on JIS A 5908 (2003), and the result of physical properties as follow : 1) Density met the standard at 0.77 - 0.99 g/cm, 2) The value of moisture content were below on target and the standard because of the hidrofobicity of PE, the range were 0.79 - 3.06%, 3) Thickness swelling of the board for 24 hours fulfill the standard the value were 0.44 - 2.77%. Unfortunatelly the water absorption were 2.82 - 16.19%. Mechanical properties consist of modulus elasticity (MOE), modulus rupture (MOR) and screw holding strength didn’t meet the criteria of JIS A 5908 (2003), except MOR with plastic: particle 60:40 with particle made of inner stem. Keywords: Composite board, oil palm stem, polyethylene (PE

The Quality Of Composite Board Made Of Waste Oil Palm Stem (Elaeis Guineensis Jacq) And Recycle Polyethylene (Pe)

The main objective of this research was to find out the substitution of solid wood and it may solve environmental problem. These researches concerned on using waste of oil palm stem particle form and recycle plastic polyetyhlene (PE) as raw materials for composite board. In this research, 5% Maleic Anhydride (MAH) was added to increase compatibility and 0.75% Dicumyl Peroxide (DCP) was added to initiate the reaction of maleolation. The methods of this research followed JIS A 5908 (2003) with ratio of plastic to particle were 50:50, 60:40 and 70:30, respectively, pressed at 30 kgf/cm2 in 165°C for 15 minutes. Evaluation on physical and mechanical properties based on JIS A 5908 (2003), and the result of physical properties as follow : 1) Density met the standard at 0.77 - 0.99 g/cm, 2) The value of moisture content were below on target and the standard because of the hidrofobicity of PE, the range were 0.79 - 3.06%, 3) Thickness swelling of the board for 24 hours fulfill the standard the value were 0.44 - 2.77%. Unfortunatelly the water absorption were 2.82 - 16.19%. Mechanical properties consist of modulus elasticity (MOE), modulus rupture (MOR) and screw holding strength didn’t meet the criteria of JIS A 5908 (2003), except MOR with plastic: particle 60:40 with particle made of inner stem. Keywords: Composite board, oil palm stem, polyethylene (PE

Development of oriented strand board from acacia wood (Acacia mangium willd): effect of pretreatment of strand and adhesive content on the physical and mechanical properties of OSB.

Acacia wood (Acacia mangium Willd.) is the most popular fast growing tree species planted in timber estate in Indonesia and is considered to be very valuable raw materials for structural composite products. The objective of the research was to evaluate the propet1ies of OSB prepared from A. Mangium wood with or without immersing the strands to hot water at 80°C for 2 hours. MDI adhesive was used in 3 levels i.e., 3%, 5%, and 7%. The moisture content of strand was 7%. The results indicated that immersing strands in hot water for 2 hours at 80°C prior to manufacture OSB improved significantly the mechanical properties (i.e., MOR and MOE) of OSB. The higher the adhesive content resulted in the better the dimensional stabilisation (i.e., water absorption and thickness swelling) and the mechanical properties (i.e., MOR, MOE and IB) of OSB. OSB prepared from hot-water immersed strands with 5% adhesive content has met all parameters requirement on the JIS A 5908 (2003) standard