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Studies on advantageous of natural fillers incorporated into polymer composites on thermo-physical and mechanical properties are still intensively investigated. Several evidences suggest that the natural fillers with small contents combined with polymer increase their composite properties. We thus investigate thermo-physical properties of kenaf-filled acrylonitrile butadiene styrene (ABS) composites. ABS with 5% kenaf microparticle size (ABS/K5), ABS with 5% kenaf short fiber (ABS/KSF5), and recycled ABS with 5% kenaf microparticle size (RABS/K5) were manufactured. Granular composites were manufactured by the twin screw extruder. Composite properties in terms of X-ray diffractions, surface morphologies, and thermal behaviors were investigated. The present work found that ABS/KSF5 has the highest degree of crystallinity compared to others. No significant difference was found in terms of thermal properties of the composites.

In this study, the effect of different extraction solvents on the isolation and properties of cellulosic nanofibers (CNFs) were investigated. The unextracted and different solvent-extracted CNFs formed horn-like features and irregularly aggregated nanofibers after oven drying. Scanning electron microscopy at 10000× magnification revealed the smooth external surfaces of all extracted CNFs; this finding is attributed to the limited deposition of amorphous lignocellulosic components on the fibers. All resultant CNF solutions revealed aggregation, with a particle size distribution and zeta average of 21.39-513.00 nm and 162.26-342.13 nm, respectively. Extraction with different solvents and chemical treatment yielded CNF solutions with good transparency. Increases in crystallinity indices were generated by extractive removal and enhanced the delignification and bleaching processes. The atomic crystal size of untreated and different solvent-treated CNFs varied with the type of native cellulose. A dramatic decrease in organic (i.e., C, N, and O) and inorganic (i.e., Na, K, and Si) elements was observed following extractive removal and cellulose purification. [ABSTRACT FROM AUTHOR]

Effects of alkali washing were determined after steam treatment of Betung bamboo strands relative to the properties of the bamboo oriented strand boards (BOSBs). The strands were subjected to steam treatment at 126 °C for 1 h under 0.14 MPa of pressure, followed by washing with sodium hydroxide solution at concentrations ranging from 1% to 5% for 30 s. Three-layer BOSBs were manufactured with a target density of approximately 0.7 g/cm³ using 8% phenol formaldehyde resin with the addition of 1% wax. The shelling ratio of the BOSBs was set to be 1:1:1. The physical and mechanical properties increased significantly with the alkali washing treatment at concentrations from 1% to 3%, and the greatest properties were obtained by washing at 3% alkali concentration. However, the washing treatment at concentrations of 4% and 5% reduced the physical and mechanical properties of the BOSBs. [ABSTRACT FROM AUTHOR]

A novel isolation of oil palm empty fruit bunch lignocellulose nanofibers (LCNFs) was successfully applied using multimechanical stages assisted with different vibration milling times. Morphology, physical, chemical, and thermal properties of LCNFs were studied. All LCNF samples were agglomerated due to hornification process during the drying of its suspension. The external surface of the nanofibers was irregular, uneven, folding, and unsmooth with approximate nanofibers diameter of above 100 nm. The optimal size of oil palm empty bunch LCNFs was in the range of 53.72-446.80 nm. Bio-oil was suspended in all LCNF samples after analysis with GC-MS in which the most dominant extractives were aromatic and oxygenated compounds. The increase in milling time could lead to the decrease in silica and oxygen elemental compositions. IR analysis revealed that there were no pronounced changes of transmittance peaks during vibration milling processes. The increase in milling time induced the decrease in atomic crystal size of LCNFs but the increase in crystallinity index from 7 to 17 milling times. A pretreatment of 7 vibration milling times to LCNFs brought about the lowest thermal stability. [ABSTRACT FROM AUTHOR]

Exploration of natural resources as composite fillers is still under intensive investigation. Previous works mention that nano-size natural fillers provide an alternative solution to improve certain composite properties compared with macro- and micro-size nanofibers. This work prepared biocomposites formulated from recycled acrylonitrile butadiene styrene (ABS) reinforced by nano powders or long fibers of oil palm empty fruit bunch (OPEFB). Composite properties in terms of density, Fourier transform infrared spectroscopy, surface morphology, melt flow rate, tensile strength, impact strength, and hardness were studied. The density of all composites generally increased with increasing filler loading. Composites with nano powder fillers had lesser voids than those composites with the long fiber. Melt flow rate of all composites fluctuated with filler loadings. Increasing filler loadings for composites with long fiber increased brittleness. By contrast, composites with nano powder fillers were more elastic at the higher filler loading. It was confirmed that impact and hardness properties of the composites with nano powder fillers increased with increasing filler loading. Moreover, composites with long fiber fillers decreased their impact and hardness properties with filler loadings increase. [ABSTRACT FROM AUTHOR]

The performance of helmet prototypes fabricated from acrylonitrile butadiene styrene composites filled with oil palm empty fruit bunch fibers was evaluated. The fibers were produced using a milling procedure, while the composites were fabricated using a single-screw extrusion. The physical characteristics of the produced fibers, which are water content, size, and density, were investigated. In addition, the mechanical properties of the produced helmets, including shock absorption, yield stress, frequency, and head injury criterion (HIC), were examined. The impact strength of the produced helmets increases with the rise of filler content. In addition, the helmets were also able to withstand a considerable pressure such that the transmitted pressure was far under the maximum value acceptable by the human skull. The present work also found that HICs exhibited by the investigated helmet prototypes fulfill all the practical guidelines as permitted by the Indonesian government. In terms of novelty, such innovation can be considered the first invention in Indonesia since the endorsement of the use of motorcycle helmets. [ABSTRACT FROM AUTHOR]

It is well-recognized that the sulfur to accelerator (S/A) ratio greatly influences the nature of rubber vulcanizates. Viscoelasticity, vibration damping, and thermal stability are important properties of rubber vulcanizates used in vibration isolators. This study aimed to assess the effects of sulfur to 2-2'-dithiobenzothiazole (MBTS) accelerator ratio on viscoelastic, vibration damping, and thermal stability of gum natural rubber (NR) vulcanizates. The viscoelastic and vibration damping properties were determined by using a rubber process analyzer (RPA), while the thermal stability was investigated by thermogravimetric analysis (TGA). The results showed that the gum NR vulcanizates prepared with a sulphur to MBTS accelerator ratio at 1.11 had the best viscoelastic and vibration damping properties for use as a rubber isolator. However, regarding thermal stability, the gum NR vulcanizates prepared with sulfur to MBTS accelerator ratio at 2.15 were superior to the others. [ABSTRACT FROM AUTHOR]