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Improving the accessibility of cellulose is essential for the production of derivative products. This can be achieved by modifying its physicochemical properties. This research aimed to investigate the properties of cellulose extracted from the torch ginger stem. The cellulose was pretreated with FeCl3 and then hydrolyzed using HCl vapor at a 37% concentration. Hydrolysis was conducted in a pressurized HCl vapor system at 27.60 kPa and 30 °C for 0–24 h. Similar treatment was conducted to cellulose without FeCl3 (unpretreated). The results show that FeCl3 pretreatment significantly decreased degree of polymerization (DP) from 0 to 24 h compared to unpretreated cellulose. The hydrolysis reaction occurred above the saturation point of HCl. When the cellulose was hydrolyzed with HCl vapor, cellulose morphology, thermal properties, and functional groups remained largely unchanged, respectively, as observed by FESEM, TGA, and FTIR methods. However, the X-ray diffractograms and FTIR spectra revealed that decrystallization of FeCl3 pretreated cellulose occurred after 10 h of hydrolysis. The 24 h hydrolysis yield for FeCl3 unpretreated and pretreated cellulose was 90.6% (DP of 118) and 86.8% (DP of 76), respectively. Therefore, this hydrolysis system can be considered an important pretreatment method for preparing cellulose derivatives. [ABSTRACT FROM AUTHOR]

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.

The anatomical characteristics in the culms of the four promising Indonesian bamboo species, including Dendrocalamus asper, Dendrocalamus giganteus, Bambusa vulgaris var. vulgaris, and Bambusa vulgaris var. striata, were investigated to produce an identification key and quality indices for further effective utilization. The crystalline properties of the bamboo culm were determined using X-ray diffraction analysis. Dendrocalamus asper and Bambusa vulgaris var. striata showed vascular bundle type IV, while Dendrocalamus giganteus and Bambusa vulgaris var. vulgaris displayed vascular bundle type III. The vascular bundle density in the bamboo culms increased from the bottom to the top part and was higher in the outer part than in the inner part. The fiber portion and length in the outer part were higher than those in the inner part, opposite of those in the parenchyma portion. Dendrocalamus giganteus had the largest vessel and parenchyma diameter, while Bambusa vulgaris var. vulgaris had the smallest. Bambusa vulgaris var. vulgaris had the longest parenchyma, while Bambusa vulgaris var. striata and Dendrocalamus giganteus had the shortest. The outer part of the four bamboo culms showed higher relative crystallinity than the inner part. All anatomical parameters, except for crystallite width, showed a variation in the radial direction of the four bamboo culms but did not show a consistent tendency vertically. This study revealed that the anatomical properties were different between bamboo species and could be used for species identification and quality evaluation indices of the culms. [ABSTRACT FROM AUTHOR]

This systematic literature review aims to study the thermal properties (TP) of poly(acrylic acid)-based hydrogels (PAA) by differential scanning calorimetry. The data sources were obtained from Google Scholar via Publish or Perish software from 2018 to 2020. The synthesis results show that most of the analysis of TP in PAA-based hydrogel consists of glass transition temperature ( T g ), melting temperature ( T m ), and enthalpy (Δ H m ). The subsequent thermal properties analysis is important for a new development and depth study in the future application. [ABSTRACT FROM AUTHOR]

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]

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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 fibers of oil palm empty fruit bunch (OPEFB) stalks were investigated to determine the changes in their basic properties after oven-heat treatment. The oven-heat treatment was conducted at 100℃ or 190℃ for 15 min. There were slightly noticeable morphological, chemical, and thermal alterations in oven-heat treated OPEFB stalk fibers for short duration. Scanning electron microscopy (SEM) revealed that the treated fibers had smooth surfaces and irregular heavy deposition of cementing agents. The highest cellulose content (41.68%) was present in OPEFB stalk fibers treated at 100℃ for 15 min, whereas the highest crystallinity index (48.74%) occurred in fibers treated at 190℃ for 15 min. The fibers comprised cellulose, lignin, and hemicellulose with a high percentage of C, O, K, and other elements. Based on differential scanning calorimetry (DSC) analysis, oven-heat treated and untreated OPEFB stalk fibers had similar thermal stability characteristics. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effect of ammonium persulfate's (APS) oxidation time on the characteristics of the cellulose nanocrystals (CNCs) of balsa and kapok fibers after delignification pretreatment with sodium chlorite/acetic acid. This two-step method is important for increasing the zeta potential value and achieving higher thermal stability. The fibers were partially delignified using acidified sodium chlorite for four cycles, followed by APS oxidation at 60 °C for 8, 12, and 16 h. The isolated CNCs with a rod-like structure showed an average diameter in the range of 5.5–12.6 nm and an aspect ratio of 14.7–28.2. Increasing the reaction time resulted in a gradual reduction in the CNC dimensions. The higher surface charge of the balsa and kapok CNCs was observed at a longer oxidation time. The CNCs prepared from kapok had the highest colloid stability after oxidation for 16 h (−62.27 mV). The CNCs with higher crystallinity had longer oxidation times. Thermogravimetric analysis revealed that the CNCs with a higher thermal stability had longer oxidation times. All of the parameters were influenced by the oxidation time. This study indicates that APS oxidation for 8–16 h can produce CNCs from delignified balsa and kapok with satisfactory zeta potential values and thermal stabilities. [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]

The creative fashion industry produces several textile products that play an important role in the national economy. In various countries, this industry has continued to grow along with the strong flow of information technology and e-commerce. The development of textile products for fashion is very dynamic and competitive. Competition is not only about price, but also the quality of organic/synthetic materials, the comfort provided, and designs that change every 4−6 months. Recently, creative fashion not only relies on natural and synthetic polymer-made fibers but also biomass-based waste materials. Therefore, this study aims to manufacture textile products from biomass-based waste materials that can be applied to the creative fashion industry. Two types of raw materials from oil palm empty fruit bunches (EFB), namely, whole-empty fruit bunches (WEFB) and stalk-empty fruit bunches (SEFB), are used as an excellent innovation of rayon viscose fiber (RVF), a noncotton organic yarn capable of providing a solution to the 99% import of global cotton needs. This is expected to increase competitiveness, as well as the added value of palm oil products and their derivatives. The process of manufacturing DP chemically includes prehydrolysis, cooking, bleaching to dissolve the lignin and noncellulosic materials as well as isolation to purify POEFB fiber. Furthermore, DP testing is carried out to determine product quality and compare it with the national product standards. The results show that the alpha-cellulose content reaches >94% with variations in the active alkali of 18%, 20% and 24%. This implies that the WEFB and SEFB are used to fulfill the first requirements of the national standard (SNI 938:2017). The WEFB with an active alkali variation of 24% meets the SNI standard for rayon pulp with a value of S10 = 3.07 and S18 = 7.14%, while all variations of SEFB show opposite results. The use of active alkali at 24% had a brighter color than between 18% and 20%. Additionally, the fiber density of WEFB appears to be higher than that of SEFB. These results correlate positively with DP prepared using 24% alkali as the optimum treatment for all products, as well as the morphological observations performed with scanning electron microscopy (SEM), which shows that WEFB fixated fiber had a larger diameter than SEFB.