Articles

Found 18 Documents
Search

BENDING STRENGTH OF LIGNOCELLULOSIC MATERIALS IN SOFTENING CONDITION Dwianto, Wahyu; Damayanti, Ratih; Darmawan, Teguh; Sejati, Prabu Satria; Akbar, Fazhar; Adi, Danang Sudarwoko; Bahanawan, Adik; Amin, Yusup; Triwibowo, Dimas
Indonesian Journal of Forestry Research Vol 7, No 1 (2020): Indonesian Journal of Forestry Research
Publisher : Secretariat of Forestry Research and Development Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20886/ijfr.2020.7.1.59-70

Abstract

This research aimed to understand the softening behaviour and viscoelastic property of wood, rattan, and bamboo as lignocellulosic materials. Nine years-old fast growing teak wood [Tectona grandis L.f.], rattan [Calamus sp.], and 3 years-old andong bamboo [Gigantochloa pseudoarundinaceae (Steud.) Widjaja] were used for the experiments. The samples were taken from the bottom, middle and upper parts for wood and rattan, and that for bamboo were cut from the 1st to 20th internodes. Static bending tests were carried out in fresh (green) as control samples, air-dried, and softened by microwave heating (MW) for 1 min to determine modulus of rupture (MOR) and modulus of elasticity (MOE). The results showed that the MOR and MOE values of wood, rattan, and bamboo increased from fresh to air-dried condition, and decreased by MW. When compared at the same density, drastic increase was observed for the normalized MOR value in air-dried of rattan, i.e. 2.5 fold. However, the decreasing of all the normalized MOR values were almost the same, i.e. 0.5 fold when they were softened by MW. Remarkably increase was also appeared for the normalized MOE value in air-dried of rattan, i.e. 3.0 fold and decreased to almost zero by MW. These results indicated that rattan was more easily bent, followed by bamboo and then wood. Hydrothermal properties of chemical components significantly affected the changes of strength (MOR) and elastic properties (MOE). However, the differences in bending strength of wood, rattan, and bamboo were more likely due to differences in their anatomical structures.
FIRE RESISTANCE MEASUREMENT OF OIL PALM EMPTY FRUIT BUNCH-PLASTIC COMPOSITES BY COMBUSTIBILITY TEST Dwianto, Wahyu; Karina, Myrtha
Jurnal Sains Materi Indonesia Vol 9, No 2: FEBRUARI 2008
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (122.165 KB) | DOI: 10.17146/jsmi.2008.9.2.4749

Abstract

FIRE RESISTANCE MEASUREMENT OF OIL PALM EMPTY FRUIT BUNCH-PLASTIC COMPOSITES BY COMBUSTIBILITY TEST. This paper reports combustibility test of Oil Palm empty fruit bunch (EFB)-plastic composites to determine their fire resistance. Specimens were of several composite types with dimension of 40 x 40 x 50 mm3. Combustibility test was done according to JIS A 1321-1975 by using small scale cylindrical furnace. Initial temperature of furnace was set at 750 ºC ± 1 ºC. Based on JISA1321-1975, all the composites tested were classified into combustible materials due to their temperature gradient higher than 50 ºC. The lowest temperature gradient was attained at 75 ºC for PE-EFB/GF/GF short fibers composite. However, the result showed that the temperature gradient of PE-EFB/GF/GF short fibers composite was lower compared to some solid woods and commercial wood-based panels. Weight loss has a strong relationships with density of the composites, shown by polynomial equation y = -181.82 x2 + 452.36 x - 205.5, R2 = 0.9156. The density of composites which formed EFB layers tended to decrease, conscequently increased their weight loss. Concerning the both factors, PE-EFB/GF/GF short fibers composite was recommended as the best fire resistance among the tested composites due to its lowest temperature gradient (75 ºC) and relatively lower weight loss (64.17 %).
CENTRAL KALIMANTAN’S FAST GROWING SPECIES: SUITABILITY FOR PULP AND PAPER Adi, Danang Sudarwoko; Wahyuni, Ika; Risanto, Lucky; Rulliaty, Sri; Hermiati, Euis; Dwianto, Wahyu; Watanabe, Takashi
Indonesian Journal of Forestry Research Vol 2, No 1 (2015): Indonesian Journal of Forestry Research
Publisher : Secretariat of Forestry Research and Development Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (624.734 KB) | DOI: 10.20886/ijfr.2015.2.1.%p

Abstract

Fast growing wood species could be promising to fulfill the gap between wood demand and supply. Due to their low quality, the utilization of fast growing wood species has been limited to pulp and paper. Our previous study on the fiber characteristic and density of the 30 unutilized fast growing wood species from PT Sari Bumi Kusuma, Central Kalimantan, showed that there were five species which could be promising as pulp and paper material. These wood species have fiber lengths of more than 2200 µm. This research was conducted to get information another property of the five woods to more discover their potential utilization, especially for pulp and paper material. The wood species investigated were Endospermum diadenum, Dillenia sp., Adinandra dumosa, Adinandra sp., and Nauclea junghuhnii. The results showed that these five species have a long of fiber length, which are classified in Class I, low to medium density, fiber derived value which the total score felt in the class I. The chemical compositions showed that extractive, holocelullose, α-cellulose, and lignin contents were 1.74-4.12%, 62.73-73.83%, 37.24-46.97%, 29.68-38.92%, respectively. Based on fiber characteristic, density, and chemical properties, these five species could be used as an alternative raw material for pulp and paper industries. 
CENTRAL KALIMANTAN’S FAST GROWING SPECIES: SUITABILITY FOR PULP AND PAPER Adi, Danang Sudarwoko; Wahyuni, Ika; Risanto, Lucky; Rulliaty, Sri; Hermiati, Euis; Dwianto, Wahyu; Watanabe, Takashi
Indonesian Journal of Forestry Research Vol 2, No 1 (2015): Indonesian Journal of Forestry Research
Publisher : Secretariat of Forestry Research and Development Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (624.734 KB) | DOI: 10.20886/ijfr.2015.2.1.21-29

Abstract

Recent studies of  fast growing species grown in PT. Sari Bumi Kusuma, Central Kalimantan, show that based on their fiber dimensions there are five species, namely Endospermum diadenum, Dillenia spp., Adinandra dumosa, Adiandra sp., and Nauclea junghuhnii with good potential for pulp and paper production.  The fiber length of  those five wood species are was more than 2,200 µm on average. This paper studies the physical properties, fiber dimensions and their chemical contents to predict the paper and pulp quality. The result shows that all of  the species were classified in the medium to high density category. All species were classified into the first class quality for pulp and paper. Based on chemical contents, Dillenia sp. is the most suitable species due to its high value of  holocellulose and a-cellulose, low lignin content, and its fiber length is about 3,119 µm on average. A. dumosa also has good opportunities because it had the longest  fiber lengths (3,137 µm on average) and high value of  holocellulose, even though it has the highest lignin content. While Nuclea junghuhnii is  less suitable due to low values of  holocellulose and a-cellulose.
EXPLORATION OF POTENTIAL TREE SPECIES IN SUMBA ISLAND Lestari, Eka; Amin, Yusup; Pramasari, Dwi Ajias; Dwianto, Wahyu
Teknologi Indonesia Vol 41, No 1 (2018)
Publisher : LIPI Press

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (16.054 KB) | DOI: 10.14203/jti.v41i1.446

Abstract

ABSTRACTSumba Island is a part of Wallace region which located in between Asia and Australia continents. Therefore it has a lot of endemic flora and fauna species. Laiwangi Wanggameti National Park (LWNP) is one of area in Sumba Islands which represented of this condition. The aim of this study is to determine the potential of tree species in Sumba Island based on strength class and commercial class. The wood samples were taken from 9 plots by wood increment borer at 1.3 meters height (breast height). The physical properties (specific gravity) were measured to determine the wood strength classes. The results found 35 species of potential tree species which can be classified into strength class II (13 species), III (19 species), IV (2 species), and V (1 species). Based on commercial classes, 63% of the tree species were classified into lesser known timbers. Furthermore, we think the potential tree from LWNP can be used for research purpose in forestry, especially in domestication study. Keywords: wood strength class, commercial class, bor riap, Laiwangi Wanggameti National Park, domestication ABSTRAKPulau Sumba merupakan bagian dari kawasan Wallacea yang berada di antara Benua Asia dan Australia. Oleh karena itu, pulau ini memiliki banyak flora dan fauna endemik. Taman Nasional Laiwangi Wanggameti (TNLW) adalah suatu wilayah di Pulau Sumba yang merepresentasikan kondisi secara umum di kawasan tersebut. Tujuan dari penelitian ini adalah untuk menentukan jenis kayu potensial di Pulau Sumba berdasarkan kelas kuat dan kelas komersial. Sampel kayu diambil dari 9 plot dengan menggunakan bor riap pada ketinggian 1,3 meter (setinggi dada). Sifat fisik (berat jenis) diukur untuk menentukan kelas kuat kayu. Hasil menunjukkan bahwa ditemukan 35 jenis kayu yang potensial yang dapat diklasifikasikan ke dalam kelas kuat II (13 jenis), III (19 jenis), IV (2 jenis), dan V (1 jenis). Berdasarkan kelas komersial, 63% jenis kayu yang didapatkan merupakan jenis kayu yang kurang dikenal. Oleh karena itu, jenis-jenis kayu yang potensial dari TNLW ini dapat digunakan untuk kepentingan penelitian di bidang kehutanan, lebih khususnya pada penelitian tentang proses domestikasi jenis-jenis tersebut. Kata Kunci: kelas kuat kayu, kelas komersial, increment borer, Taman Nasional Laiwangi Wanggameti, domestikasi
Sifat Ketahanan Api Lima Jenis Kayu dengan Pelapisan Carbon Phenolic Spheres (CPS) yang Diuji dengan Cone Calorimeter Fire Resistance Properties of Five Wood Species Laminated with Carbon Phenolic Spheres (CPS) Tested by Cone Calorimeter Subyakto, Subyakto; Dwianto, Wahyu
Jurnal Ilmu dan Teknologi Kayu Tropis Vol 2, No 1 (2004): Jurnal Ilmu dan Teknologi Kayu Tropis
Publisher : Jurnal Ilmu dan Teknologi Kayu Tropis

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (206.978 KB)

Abstract

In all aspects of wood utilization their fire resistance properties are very important; therefore efforts to enhance those properties are needed. In the previous study, graphite phenolic spheres (GPS) laminated on woods and plywood enhanced their fire properties. Carbon phenolic spheres (CPS) is a new material made from a mixture of wood char and phenolic resin, this material is cheaper than GPS. In the present experiment, CPS sheet was laminated on five wood species and their fire resistance properties were evaluated using cone calorimeter. The five wood species are randu (Bombax ceiba L.), angsana (Pterocarpus indicus Jacq.), mindi (Melia azedarach L.), puspa (Schima wallichii DC Korth), and mahoni (Swietenia mahagony L. Jacq). The specimen was 100 mm x 100 mm with thickness of 30 mm tested with cone calorimeter in accordance with ISO 5660 standard. Using cone calorimeter a homogenous heat was exposed to the surface of wood specimen, and ignited with igniter. About 1 mm thick of CPS sheet was laminated on the wood surface (100 mm x 100 mm). Specimen was tested at horizontal position and at heat flux of 40 kW/m2. On the unexposed wood surface, thermocouple was attached to measure increases of temperature. Results showed that five species of wood laminated with CPS have higher fire properties compared with control wood, however compared with woods laminated with GPS those results were lower. 
Pengaruh Dimensi dan Pre-kompresi Kayu terhadap Sifat Penyerapan Air Dimensions and Pre-Compression Wood Influences on Water Absorption Suryanegara, Lisman; Dwianto, Wahyu
Jurnal Ilmu dan Teknologi Kayu Tropis Vol 2, No 2 (2004): Jurnal Ilmu dan Teknologi Kayu Tropis
Publisher : Jurnal Ilmu dan Teknologi Kayu Tropis

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (149.546 KB)

Abstract

This research attempted to understand the effect of dimension and pre-compression on water absorption behavior of wood. Wood samples were water immersed at room temperature and 60°C for 48 hours in certain periods. Retention, weight gain and recovery level were observed.The results showed that water absorption mostly depended on radial and tangential area for un-compressed wood. For pre-compressed wood, the different of water immersion temperature caused recovery level differences. The retention of pre-compressed wood samples which 60°C water immersion for 48 hours were higher than that of un-compressed wood samples
Karakteristik LVL Lengkung dengan Proses Kempa Dingin Characteristic of LVL Bent by Cold Press Process Darmawan, Teguh; Dwianto, Wahyu; Amin, Yusup; Prasetyo, Kurnia Wiji; Subiyanto, Bambang
Jurnal Ilmu dan Teknologi Kayu Tropis Vol 7, No 2 (2009): Jurnal Ilmu dan Teknologi Kayu Tropis
Publisher : Jurnal Ilmu dan Teknologi Kayu Tropis

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (334.548 KB)

Abstract

Bending LVL (Laminated Veneer Lumber) is a more effisien method to manufacture bent wood components compare to other methods in raw materials point of view. The Bending LVL was made from Sengon veneers by cold press process with variation of Water Based Polymer-Isocyanate adhesive of 250, 280, 310 g/m2 and bend radius of 200,300, 400 mm. The results showed that the physical properties of Bending LVL made by using Water Based Polymer-Isocyanate adhesive and cold press process was fit with JAS 1639/1986 standard. The optimum adhesive concentration and bend radius was 250 g/m2 and 20 cm, respectively
Fiber and Chemical Characteristics of Branchwoods of Three Meranti Species Adi, Danang S; Risanto, Lucky; Wahyuni, Ika; Kusumah, Sukma S; Dwianto, Wahyu; Hayashi, Taka
Jurnal Ilmu dan Teknologi Kayu Tropis Vol 9, No 2 (2011): Jurnal Ilmu dan Teknologi Kayu Tropis
Publisher : Jurnal Ilmu dan Teknologi Kayu Tropis

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (325.964 KB)

Abstract

The fiber and chemical characteristics of branchwoods of three meranti species namely meranti sangkan, meranti bakau, and meranti bunga kulit hitam from Bukit Batu Peat Swamp Forest, Riau were observed. The aim of this research was to discover the potential utilization of these three meranti species based on their characteristic. The result showed that holocellulose contents of meranti sangkan, meranti bakau, and meranti bunga kulit hitam were 72.97%, 75.28%, and 69.88%, whereas the α-cellulose contents were 43.55%, 51.14%, and 43.25%, respectively. meranti sangkan had the highest lignin content (35.99%) followed by meranti bakau (34.21%) and meranti bunga kulit hitam (32.18%). meranti Bunga kulit Hitam had the highest extractive content (2.24%) followed by meranti sangkan (1.66%) and meranti bakau (1.08). Furthermore, the fiber length of meranti bunga kulit hitam, meranti sangkan, and meranti and meranti Hitam were 1475.45 μm, 1475.45 μm, 1442.62 μm, and 1205.23 μm, respectively. The values of fiber derivative of the three meranti species were slightly differ from class I, except for felting power that was classified in class III. The result also showed that the branchwoods of the three meranti species are suitable for pulp and paper raw material.Key words: fiber and chemical properties, meranti bakau, meranti sangkan, meranti bunga kulit hitam, peat swamp forest
The Effect of Steaming and Heat-Compression on the Properties of Jabon Wood for Furniture Materials Basri, Efrida; Abdurachman, Abdurachman; Dwianto, Wahyu
Jurnal Ilmu dan Teknologi Kayu Tropis Vol 12, No 2 (2014): Jurnal Ilmu dan Teknologi Kayu Tropis
Publisher : Jurnal Ilmu dan Teknologi Kayu Tropis

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (294.772 KB)

Abstract

The inferior properties of juvenile jabon wood (Anthocephalus cadamba Miq.) limit its utility. Densification through heat-compression presently conducted is possibly useful to improve its properties. Preceding heat-compression, jabon wood samples were either steamed or non-steamed. Heat-compression temperatures were varied at 170 C, 180 C and 190 C. Compression was carried out until 20% reduction in wood thickness. Physical and mechanical properties and machining properties of the compressed wood samples were determined in accordance with standard procedures of ASTM D143-94 and ASTM D1666-64, respectively. In the present works, both of the ASTM standard referred were slightly modified. X-ray diffractometer (XRD) was used to determine crystallinity degree of wood. The result showed that either steamed or not, densification was successfully increased the properties of juvenile jabon wood and satisfied the requirement of wood for furniture raw materials.Keywords: furniture, heat pressure, steaming, wood properties, young age-jabon