Vol 1, No 2 (2008)

Jurnal Ilmu Teknologi Hasil Hutan

Table of Contents

Articles

The research was conducted on four wood species with small of diameter, originated from Sukabumi, i.e. huru gading (Litsea odorifera Val.), sampora (Colona javanica Burr.), kisampang (Evodia aromatica BL.) and nyatuh (Pouteria duclitan Bachni). The resistance properties of those four wood species after being metal-screwed against seven wood-destroying fungi were evaluated using modified DIN 52176 standard (Martawijaya, 1975). Results showed that decaying rates (weight losses) of the screwed wood were generaly greater than those of control (unscrewed wood). The highest weight loss was encountered on unscrewed kisampang wood exposed to Pycnoporus sanguineus HHB-324 (49.33%), while the lowest loss was found on unscrewed huru gading wood exposed to Dacryopinax spathularia (0.69%). Three of four wood species tested (i.e. sampora, kisampang and nyatuh) both being screwed and unscrewed were categorized as not resistant (class IV), whereas screwed huru gading wood was moderately resistant (class III) and the unscrewed one was resistant (class II). Based on corrosion, the highest weight loss of screw was obtained on kisampang wood tested by C. globosum (11.33%). However, the lowest screw weight loss was on huru gading tested by Polyporus sp. (1.95%). Among the fungi, the most severe attacks on wood was performed by P. sanguineus HHB-324. Based on ability to corrode wood-associated screw, there were no significant different among five of the seven fungi, whereas Polyporus sp. and  P. sanguineus HHB-324 were performed lower ability.

 

Keywords:  Resistance properties, wood destroying fungi, metal screw, weight loss

DJARWANTO ., Sihati SUPRAPTI
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The objectives of this research were to determine and to compare the physical and mechanical properties of OSB made of strands from three small diameter fast growing species, namely  Akasia (Acacia mangium Willd.), Ekaliptus (Eucalyptus sp.), and Gmelina (Gmelina arborea Roxb.). There were 3 models of OSB produced which bonded by 2 types of adhesive, namely Phenol Formaldehyda (PF) powder type, isocyanate (IC), and the face and back layers bonded by powder PF and the core layer bonded by IC. OSB was made of  three plies, with 9 mm target thickness and ratio of strands weight in face : core : back was 1:1:1. Mat forming methods in face was lengthwise and  the core was widthwise. Level of adhesive 7% based on oven dry strands weight, pressed at 25 kg/cm2 for 15 minutes at 160 °C. Japanese Industrial Standard (JIS) A 5908-2003 for particle board 24-10 type was used as standard. Results of this research showed generally physical properties consist of density, moisture content, and thickness swelling fulfilled JIS A 5908-2003 standard. Unfortunatelly, the dimensional stability should be improved, the range 24 hours water absorption was about 22.35–44.63%. For mechanical properties, which consist of internal bonding, modulus of rupture (MOR) and modulus of elasticity (MOE) which be evaluated in dry condition both lengthwise and widthwise generally fulfilled JIS A 5908-2003 standard. However, there were values of  MOR and MOE which be evaluated in wet condition both of lengthwise and widthwise did not fulfill JIS A 5908-2003 standard. The best performance of OSB was which bonded by IC for all the wood species. Using PF powder at the

face and back layers and IC in the core layer of OSB generally increased their physical properties (dimensional stability) but decreased their mechanical properties.

 

Keywords  : Physical and  mechanical properties, OSB, small diameter fast growing species, adhesive

Arif NURYAWAN, Muh. Yusram MASSIJAYA, Yusuf Sudo HADI
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Widya FATRIASARI, Euis HERMIATI
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Mohammad WIJAYA, Erliza NOOR, Tun Tedja IRAWADI, Gustan PARI
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Elyazar MANUHUWA
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The research objectives are to evaluate physical and mechanical properties of OSB based on strand orientations made from akasia wood (Acacia mangium Wild) and afrika wood (Maesopsis eminii Engl). Akasia and afrika wood are used for OSB strand material with phenol formaldehyde (PF) as adhesives and addition of paraffin. OSB made in this research consists of three plies whereas are differed into eight strand orientations.  Hot press was carried out at 160ºC and pressure 25 kg/cm² for 15 minutes. Determination of OSB physical and mechanical properties referred to JIS A 5908-2003. Result showed that strand orientations have not affected to OSB physical properties except for linear swelling 24 h, but it significantly influences all mechanical properties of OSB. Wood species has an effect on mechanical properties of OSB in the dry test, wet MOE lengthwise test and OSB physical properties, particularly to OSB density and water absorbing capability at 2 h and 24 h.  All of OSB physical properties are meet JIS A 5908-2003 standard, but not all of the mechanical properties such as dry MOE lengthwise, dry MOE and MOR widthwise. The best physical and mechanical properties is presented by OSB made from akasia wood in strand orientation F (core layer is orientated and surface layers are in random, R°/0°/R°), G (core layer is orientated 45° and surface layers are in random, R°/45°/R°), B (surface strand direction is upright to core strand direction, 0°/90º/0°), and C (core layer is in random, surface layers are orientated, 0°/R/0°) whereas all parameters meet JIS A 5908-2003 standard. In comparation with strand orientation B that is frequent used in industry, strand orientation F and G are proficient to raise the modulus elasticity value (MOE) and strength (MOR) as much as 167.8-231.7% and 89.7-109.9%, respectively; especially in widthwise board application. Furthermore, strand orientation F and G are more flexible as structural components.

Keywords:   Oriented strand board, strand orientation, phenol formaldehyde

NURHAIDA ., Naresworo NUGROHO, Dede HERMAWAN
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Botanical Garden including information on their physical  and   mechanical  properties,   natural  durability,   distribution,

prospect and other supporting data; (2) to analyze the lesser-known wood species that could be used for  construction materials and then recommend them to be developed through Industrials Plantation Forest. The steps of the study were first collection of data on timber species from herbarium catalogue; second collection of data on the properties of wood from various sources; third, observation of stem morphology in the field. The result of the catalogue study showed that there were 291 timber tree species grown in Cibodas Botanical Garden which were comprised of 14 major commercial timbers, 74 minor commercial timbers, and 142 lesser known timbers. These timber species were also distributed in other parts of Indonesia. Observation in the field then generated 49 lesser-known wood species that could be used for construction materials based on their stem form and branch height. From the reference and catalogue study, it was found that there were 14 wood species belongs to strength class I to III with natural durability ranges from very durable to moderate. These woods were then evaluated based on their morphological features and prospects. Finally, it was found that only ten wood species that were suitable to be used for construction materials, i.e. Acmena acuminatissima (Blume.) Merr. & Perry (Kelat); Adenanthera microsperma Teijsm. & Binn. (Saga); Baccaurea parviflora (Muell. Arg.) (Setambun); Casuarina junghuhniana Miq. (Cemara Gunung); Garcinia parvifolia and G. beccari (Manggis Hutan); Gymnostoma sumatranum (Joogb. ex de Vriese) L.A.S. Johnson (Cemara Sumatra); Mimusops elengi L. (Tanjung); Neonauclea lanceolata and N. obtusa (Ki Anggrit). However, the result of this study needs to be supported by further study on their wood properties since the present data were mostly qualitatives. Further research concerning their silviculture, growth rate, and susceptibility to the diseases were also needed to be done.

 

Keywords : Lesser-known timbers, Cibodas Botanical Garden.

Ika WAHYUNI, Wahyu DWIANTO, Yusup AMIN, Teguh DARMAWAN
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