FIRE RESISTANCE MEASUREMENT OF OIL PALM EMPTY FRUIT BUNCH-PLASTIC COMPOSITES BY COMBUSTIBILITY TEST

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 %)

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

<Original>Lignin-carbohydrate Complexes from Albizia falcata (L.) Back.

この論文は国立情報学研究所の学術雑誌公開支援事業により電子化されました。Lignin-carbohydrate complexes (LCCs) have been extracted from tropical hard wood of Albizia fakata (L.) Back, by a modified Bjorkman method. After extraction of milled wood lignin (MWL) from the hard wood, LCCs were isolated by successive extraction of the residual wood meal with water (LCC-WE) and 4% NaOH (LCC-AE). NMR and methylation analysis of the LCCs indicated that carbohydrate moiety of LCC-AE was composed of 4-O-methyl-glucuronoxylan while polyose component of LCC-WE consisted of glucomannan and xylan. Analysis of neutral fraction from LCC-WE revealed that this LCC contained β-1,4-linked xylan chain bearing no glucuronic acid residue. In addition, it has been clarified by DDQ-oxidation that the glucuronoxylan was directly bound to the lignin through C-2 and C-3 positions of xylose unit by ether linkage

<Note>Isolation of Syringaresinol from Paraserianthes falcataria (L.) Nielsen

この論文は国立情報学研究所の学術雑誌公開支援事業により電子化されました。A survey of lignans in Paraserianthes falcataria (=Albizia falcatarid) which is one of the most important fast growing trees in tropical Asia was carried out, and syringaresinol was isolated from the methanol extracts of heartwood

<Original>Characterization of Steam-Exploded Wood II : Chemical Changes of Wood Components by Steam Explosion

この論文は国立情報学研究所の学術雑誌公開支援事業により電子化されました。Chemical changes of main components in wood (cellulose, hemicellulose and lignin) by steam-explosion process have been elucidated by ^1H- and ^C-NMR, Gas chromatography, GPC and thermal softening property. By steam-explosion hemicelluloses were rapidly hydrolyzed to lower molecular weight products. Almost all hemicelluloses (27.9%) in Shirakanba wood were hydrolyzed to oligosaccharides to be extracted with water by only one min. steaming at 20 kg/cm^2, and 53.7% of hemicelluloses were converted to monosaccharides by 8 min. steaming at 28 kg/cm^2. Monosaccharides obtained by 2 min. steaming at 28 kg/cm^2 of Shirakanba wood were composed of 61.1% of xylose and only 4.9% of glucose, and the yields were in accord with original composition of hardwood hemicelluloses. Cellulose in non-crystalline area was partially hydrolyzed, and micelle length was decreased to about 2000 Å by 8 min. steaming at 28 kg/cm^2. However, cellulose was not hydrolyzed to glucose, and non-crystalline cellulose would be annealed and transformed to crystalline celluslose. Thus the crystallinity and micelle width of cellulose were increased by steam explosion treatment. However, when reaction time was increased, the yields of furfural and 5-hydroxymethylfurfural derived from polysaccharides were increased. Lignin was degraded slower than hemicelluloses. The yield of lignin was 29.2% in maximum by 8 min. steaming at 28 kg/cm^2, and the molecular weight of lignins obtained were decreased to Mw=2100 and 1100 by 2 min. and 16 min. steaming, respectively. A degradation mechanism of lignin by steam explosion was presumed to be homolytic cleavage of aryl ether linkage

Characterization of Cuticle Layer of Ilex latifolia

Cuticular membranes were isolated from the upper and lower surfaces of Ilex latifolia leaves and their morphological, chemical compositional and mechanical properties were characterized.  The upper cuticular membrane contained 18.6% wax, 53.5% cutin and 17.5% cutan with low contaminating carbohydrates (10.4%), while the lower cuticular membrane had the values of 17.9%, 49.2%, 15.8% and 17.1%.  Both membranes were rich in aliphatic CH2 groups, and the main monomer of the cutin in the upper cuticular membrane was 9(10),18-dihydroxyhexadecanoic acid while 9,10,18-trihydroxyoctadecanoic acid in the lower membrane. Mechanical analyses indicate clear orientation differences in breaking stress and strain between the two membranes with higher breaking stress in the upper cuticular membrane and in the longitudinal direction parallel to the midvein. Additive such as a cellulosic hydrogel from Salvia viridis to make a composite influenced the mechnical properties of the cuticular membranes. Mechanical properties of the isolated cuticular membranes may be more influenced by their morphological properties than chemical compositions; thick and smooth structure of the upper cuticular membrane, while wrinkled and scattered stoma-rich structure of the lower cuticular membrane

Chemical Compositions of Hydrocolloids Produced from Nutlets of Salvias

Hydrocolloids of three species of Salvias (S. miltiorrhiza, S. sclarea and S. viridis) was analyzed their chemical compositions after isolation of hydrocolloids from seed coats. Isolation was conducted after expanding out completely in water.  Hydrocolloids produced from S. miltiorrhiza, S. sclarea and S. viridis have cellulose contents about 18.6%, 25.3% and 35.4% and hemicelluloses contents about 80%, 73.4% and 62%, respectively. Native hydrocolloids produced from S. sclarea and S. viridis were rich in glucose about 48.6% and 55.4%, respectively, while the other one, S. miltiorrhiza, was rich in xylose, about 85.1%. Distribution of these polysaccharides in S. miltiorrhiza, S. sclarea and S. viridis were 86.5%, 71.0% and 63.2% (acidic polysaccharides) and 13.8%, 29.0% and 36.5% (neutral polysaccharide), respectively. Acidic polysaccharides of hydrocolloids produced from three species of Salvias contain high amount of xylose (88.8 ~ 91.9%). Neutral sugar compositions in neutral polysaccharides of hydrocolloids produced from three species of Salvias, however, were rich in glucose (25.7 ~ 37.5%) and galactose (31.3 ~ 60.4%), the ratio being changed depending on species. Acidic sugar in the acidic polysaccharides from three Salvia spp. was identified as glucuronic acid by High Performance Anion Exchange Chromatography (HPAEC). Glucuronic acid contents in the acidic fractions of S. miltiorrhiza, S. sclarea, S. viridis were estimated about 25%, 22% and 27%, respectively. These results elucidate that hydrocolloids have amorphous structure containing branch glucuronic acid in acidic polysaccharides structure. The present of glucuronic acid is predicted attach to xylan

Physical and mechanical properties of wood flour- recycle polypropylene composites under various wood flour sizes and modifier contents

The objective 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 sizes and various maleic anhydride (MAH) modifier contents. The WF – RPP composites composed of 50% WF from Eucalyptus deglupta Blume species, 50% RPP, various sizes of WF (60~80; 80~100; and < 120 mesh), various contents 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. WF size and modifier content greatly affected the physical and mechanical properties of resulted composites. 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

Precise Structure of Acidic Polysaccharide Present in Salvia Hydrogels

Precise structures of acidic ß-(1,4)-xylan in the hydrogels from three species of Salvia (S. miltiorrhiza (SM), S. sclarea (SS) and S. viridis (SV)) were characterized. SS and SV contained two different acidic residues (4-O-methylglucuronic acid (MeGlcA) and glucuronic acid (GlcA)) substituted at O-2 of ß-(1,4)-linked xylopyranose residues, whereas MeGlcA is absent in SM. Molar ratios of xylose to uronic acid are 2.0 : 1.0 (SM), 1.7 : 1.0 (SS), 1.4 : 1.0 (SV). Distribution of acidic residues in the ß-(1,4)-xylan chains was analyzed by Matrix-Assisted Laser Desorption/Ionization (MALDI)/Time of Flight (TOF) mass spectroscopy after reduction and partial hydrolysis. The results showed that many series of ions appeared as sodium adducts [M+Na]+, indicating that uronic acid residues are randomly and mixed distributed in xylo-oligosaccharide chains in the SS and SV xylans. All species showed presence of oligosaccharides in ranges of m/z 833.3~2561.2 (SM), 657.2~1655.5 (SS) and 731.2~1421.5 (SV). Acidic residues in SS and SV are distributed in shorter xylo-oligosaccharides than those in SM, although complicated substituted profiles with MeGlcA and GlcA were similarly detected in SS and SV. Presence of long free xylan chains in the SM oligosaccharides supported lower number of substituent in its xylan backbone