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Cellulose is a fascinating biopolymer and sustainable raw material. Cellulose particles with at least one dimension in the nanoscale are referred to as nanocellulose. Kenaf fiber is a natural fiber used in this study because it has high mechanical properties and strong interface adhesion with polymers so it provides superior properties to other natural fibers. Polyurethane (PU) foam is widely used as a core layer in sandwich composite construction to produce a lightweight material. This study presents a synthesis of cellulose nano-fibrils (CNF) extracted from East Java, Indonesia based kenaf fibers, an analysis of the effect of adding CNF as a filler and a reinforcement in PU foam composites, and a formulation of PU-CNF foam composite that provided the best mechanical properties as strong and lightweight materials in structural applications. The CNF extraction from kenaf fiber started by fiber pre-treatment including alkalization and bleaching, then mechanical treatment with an Ultra Fine Grinder to produce CNF suspension. The weight variations of CNF in PU foam were 0, 3, 5, 7, and 10 wt%. PU-CNF composite fabrication using the in-situ polymerization method. CNF characterization included TEM, XRD, and FT-IR. TEM results on CNF show that the CNF diameter is in the range of 40-70 nm. The functional group from the FT-IR results showed that the pre-treatment process on kenaf fiber was successful in reducing the lignin and hemicellulose content. XRD results showed that the CNF crystallinity was 75.22%. The PU-CNF foam composite characterization included a compressive test, 3-point bending test, and SEM. The PU foam composite with 3 wt% CNF reinforcement is the best composite which has the optimum value from the results of the compression test and the 3-point bending test. The compressive strength value increased by 20.01%, from 236.997 kPa to 284.434 kPa, the compressive modulus value increased by 29.21% from 5.67 MPa to 7.32 MPa, and the 3-point bending strength value increased 28.29% from 572.24 to 734.15 kPa. All the results expected to support that CNF was a potential reinforcement material with a high surface area for a wide variety of applications.

The use of liquid-solid type phase change material (PCM) is increasing due to the importance of having a good storage for latent heat, which can be attributed to its wide range of application, such as electronics, buildings, textiles, and the automotive sector. This study employed an experimental procedure through in situ mechanical mixing of paraffin-based PCM and 4Wt% Titanium dioxide (TiO2) rutile to form nanocomposite PCM with high-speed agitation (900 rpm at 90°C for 60 minutes) and mixed with Sodium Dodecyl Sulphate (SDS) as the dispersant. It was conducted by applying premixing of polar solution (distilled H20 + 4Wt% SDS dispersant) to the aforementioned non-polar paraffin-based solution (paraffin wax + 4Wt% TiO2) in a 1:4 ratio, then cooled naturally. The Fourier Transient Infrared (FTIR) spectrum and the X-Ray Diffraction (XRD) pattern indicated a characteristic typical of composite systems, in which. there is no new material system composed. The typical wavenumbers of composite PW+TiO2 (2918 cm-1, 2851cm-1, 1471 cm-1, 720cm-1 and 469 cm-1) were also seen in the FTIR, while high intensity peaks 2θ = 21.4°, 23.8 and low intensity peaks 27.4°, 36.074°, XRD patterns could be tied to monoclinic paraffin crystal with the typical plane diffractions of (110) and (200) and TiO2. The thermal properties of the composite were measured using Differential Scanning Calorimetry. The findings showed that the paraffin based PCM comprised a higher thermal storage capacity of 144.3 J/g compared to its common 104.5 J/g typology. Scanning Electron Microscope observation showed a better dispersion of TiO2 clusters (smooth, spherical, and spreading). The results ultimately showed that optimizing the agitation speed at the prompt temperature contributes to the increase of the crystallite size and the capacity to isolate the temperature of nanoparticles, which may elicit a growing interest for more practical applications of the nanocomposites PCM.

Previous studies on the physical properties of each Polyethylene (PE) or Ethylene Vinyl Acetate (EVA) foam have been widely reported. The current challenge is how to understand the combination of PE and EVA foam in order to obtain appropriate properties in various applications. Therefore, an experimental breakthrough in order to understand the physical mechanism on the PE:EVA mixed foam in order to maintain many appropriate properties due to their applications was studied. The physical properties of a combination of PE and EVA foam with Azodicarbonamide (ADC) as blowing agent and the addition of Zinc Oxide (ZnO) as accelerated agent in foaming process have been investigated in this study. The foams were prepared via two steps. Firstly, the various content of PE and EVA resins with combination of various content of ZnO and the addition of ADC, stearic acids and antioxidants were mixed by a single screw extrusion as the results of pellets. Furthermore, this intermediate product was pressed by compression moulding at the temperature of 175 °C and pressure of 30 bar for 5 minutes, then the pressure was released for the foaming process. The effect of the addition of ZnO were observed on the density and the mechanical properties of the foams. The density decreased with increasing of ZnO content up to 4 per hundred resin (phr) on the foam with PE content maximum of 20 phr. Interestingly the density of the foam increased with the addition of 6 phr of ZnO. Due to the increasing number of ZnO, we found the formation of foams completely. We observed the approval of the hardness, tensile and compression properties of each formulation, respectively. Furthermore, the morphology observation of the foams was conducted by scanning electron microscopy (SEM) to measure the size and homogeneous of the cells. We observed large size of cells at low density of foams, meanwhile uniform of cell was obtained at the high density of foams. Finally, the Fourier transform infrared (FTIR) spectroscopy confirmed that in general the intensity of the absorption peak at around 2216 cm-1 - 2223 cm-1 of each formulation decreased with the addition of ZnO up to 4 phr of ZnO and increased again at 6 phr of ZnO.

Objective:Osteoporosis could affect anyone, both men and women and young and old. This study aimed to analyse the morphology of ovariectomy (OVX) to the proximal cortical epiphysis bone using scanning electron microscope (SEM) and transmission electron microscope (TEM) on ovariectomised rat models.Materials and Methods:The analysed bones were the cortical femur bones taken from ovariectomised female Rattus norvegicus. Characterisation was performed from the third week of OVX and continued at the fifth, seventh and ninth weeks. The analysis was focused on two levels of structure, including the microstructure level with a magnification of 100 μm, which was obtained from SEM images to analyse the shape and intensity of the bone cavity, and the nanostructure level with a magnification of 50 nm, which was obtained from TEM images to analyse the bone apatite crystals.Results:At the microstructure level, the cavity that appeared in 9-week-old ovariectomised rats was found to increase by 68.9% compared to that of the control group (non-OVX). In addition, at the nanostructure level, the plate, tablet and overlapping apatite crystals were present in both the non-OVX and OVX rats. However, a tendency of the tablet size of apatite crystals to decline was observed in the ovariectomised rats group.Conclusion:White female Rattus norvegicus showed osteoporosis conditions based on the morphology and percentage of cavities at 9 weeks of OVX. In addition, OVX lowered the size of apatite crystals.

Natural fibers contained in bamboo are beneficial to renewable, biodegradable, abundant availability, and cheap which could be a potential substitute of synthetic materials. Tensile strength of this material is important requirements in various structural application. In this research, fiber fabrication process optimization of three types of local bamboo namely Gombong (Gigantochloapseudoarundinacea), HaurHejo (Bambusatuldoides), and Tali (Gigantochloa apus) was investigated. These fibers were processed by creating a variety of the NaOH concentrations of 4 % and 6 %, immersion times of 1, 2, and 3 hours, and immersion temperatures of 25 °C and 60 °C. The process parameters and its level variations of bamboo fiber fabrication were optimized using Taguchi method. Then the contribution of each process parameter was observed using the analysis of variance (ANOVA). From Taguchi method, the optimal parameter for highest tensile strength was obtained from Tali bamboo, indicated by 4 % NaOH, 2 hours immersion time, and 60 °C immersion temperature. Meanwhile, the ANOVA revealed that the contributions for each parameter are 70 % for bamboo type, 7 % for NaOH concentration, 4 % for immersion time, and 17 % for immersion temperature with error contribution of 2 %. By using these data, it could be concluded that bamboo type selection is a critical parameter to obtain bamboo with high tensile strength. While NaOH concentration, immersion time, and immersion temperature are not critical parameters which gave flexibility in the selection process. FTIR analysis was carried in order to observe chemical bonding in bamboos. The results of FTIR on the bamboo fibers were indicated Tali bamboo has larger lignin levels decreasing than HaurHejo and Gombong, this indicates in higher tensile strength for Tali bamboo fiber.

Bamboo fiber is a natural fiber that is easily degraded by microbes and potentially becomes an alternative fiber in the future due to its availability, which is abundantly cheap, and grows throughout the year and also isn’t affected by the season. The application of bamboo fiber is a solution for environmental issues and a business prospect of synthetic fibers that are expected to decrease in line with petroleum. This study presents result of the studies of various types of bamboo, fiber extraction process both mechanically and chemically, composite fabrication based on various matrices, characterization carried out to reveal performance related to the requirements of various applications, weaknesses and improvements. Based on the result of this study, the researchers obtain information related to development and research status of bamboo fiber along with the application and weakness, as well as opportunity to make some improvements.

BACKGROUND New therapeutic options are often explored in in vivo studies using animals like rats. Since rats are small, it is difficult to examine them in a computed tomography (CT) scan. This study aimed to introduce a multi-hole spherical model CT scan method as a new, fast, economical, and reliable method to characterize large quantities of rat bones at once in estimating the timing of osteoporosis in ovariectomized white rats. METHODS 50 female white rats (12 weeks old) were treated as the control group, and 40 rats of the same age were ovariectomized to establish the osteoporosis model. Sham rats were sacrificed at 13, 15, 17, 19, and 21 weeks old, while the ovariectomized rats were sacrificed at 15, 17, 19, and 21 weeks old. Afterward, tibia bones were removed, placed in the multi-hole spherical model, and characterized using a CT scan. Their characteristics were compared using a scanning electron microscope (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). RESULTS The Hounsfield unit scores resulted from the multi-hole spherical model CT scan method of tibia bones of rats were consistent with the percentage of the osteocyte cavities, canalicular diameters, and crystal size. The multi-hole spherical model CT scan method could produce 50 times more data than the SEM, TEM, or XRD. CONCLUSIONS Multi-hole spherical model CT scan was considered good and reliable in assessing bone quality parameters in rat samples simultaneously.

Bamboo particles as reinforcement in composite materials are prospective to be applied to particleboard products in the industry. This study aimed to synthesize bamboo particle reinforced polymer composites as a substitute for particleboard products, which still use wood as a raw material. The parameters of the composite synthesis process were varied with powder sizes of 50, 100, and 250 mesh, each mesh with volume fractions of 10, 20, and 30%, matrix types of polyester and polypropylene, Tali Bamboo, and Haur Hejo Bamboo as reinforcements. Characterization included tensile strength, flexural strength, and morphology. Particleboard products were tested based on JIS A 5908-2003, including density testing, moisture content, thickness expansion after immersion in water, flexural strength in dry and wet conditions, bending Young’s modulus, and wood screw holding power. The results showed that the maximum flexural and tensile strength values of 91.03 MPa and 30.85 MPa, respectively, were found in polymer composites reinforced with Tali bamboo with the particle size of 250 mesh and volume fraction 30%. Particleboard made of polypropylene and polyester reinforced Tali Bamboo with a particle size of 250 mesh and a volume fraction of 30% composites meets the JIS A 5908-2003 standard.

Lack of calcium and phosphorus minerals in bones can cause decreased bone density, bone becomes brittle and at risk of osteoporosis. The purpose of this study was to analyze changes in mineral levels and functional groups in tibia osteoporosis because of ovariectomy and were treated with a nano-calcium phosphate diet. In this research, dietary formulations containing nano-calcium phosphate made. Diets given to animal models of osteoporosis rats caused by ovariectomy with the aim to balance the mineral content in the rats tibia. Dietary formulations were made of 3 types based on their calcium content, namely the first diet (D1), the second diet (D2) and the third diet (D3) each having a total calcium content of 1.0x, 1.5x and 2.0x normal body needs. Characterization and analysis of mineral content in the tibia bone using Atomic Absorption Spectroscopy (AAS) and Ultraviolet-Visible (UV−vis), while the characterization and analysis of functional groups with Fourier Transform Infrared Spectroscopy (FTIR). Based on the data obtained, ovariectomy rats showed signs of osteoporosis with decreased levels of calcium in the tibia and a decrease in phosphate ion function groups at 9 weeks since ovariectomy. The results of dietary treatment showed that postovariectomy osteoporosis rats fed a diet with a total calcium content of 1.5x normal body needs (D2) and gave more effective and efficient results compared to diets containing 1.0x (D1) and 2.0x (D3) total calcium normal body needs.

Indonesia has many natural resources, one of which is montmorillonite which very potential to be used as a catalyst in the process converting ethanol to biofuel for an alternative fuel. Montmorillonite has unique properties, because the structure can expand and contract. Research to find alternative energy was needed to replace the limited amount of fossil energy. Chromium metal can be used as catalyst by using montmorillonite as buffer catalyst material. The purpose of this research is to make Cr/montmorillonite catalyst, which was used in the process of converting ethanol to biofuel. Cr/montmorillonite catalyst has synthesised by pillarization method, because it is simple and feasible. The conversion process was carried out by using a fixed bed reactor, peristaltic pump for flow the ethanol with flow rate 1 ml/min, and 1.5g Cr/montmorillonite pellets. The Cr/montmorillonite result was increased the basal spacing in the interlayer montmorillonite amount 150%. TGA shows the results water molecules and hydroxyl compounds decomposition process of Cr/montmorillonite in temperature 631°C. The results of the BET analysis show the specific surface area increased from 30.35 m2/g to 146 m2/g. XRF analysis shows the element content in montmorillonite, that was indicated addition of Cr metals in montmorillonite. FTIR measurements shows that the functional groups in bentonite typical peaks are Mg-OH, Si-O-Si bonds. SEM shows changes in the surface morphology particle in montmorillonite, that is for Cr particles in the form of flake. The GC-MS analysis results show the conversion of ethanol to biofuel or gasoline or biofuel.Â

Bentonite is a natural material that can used as a buffer catalysts and easy to modified. Tin and Chromium metals can used as catalyst material. Tin and Chromium metals supported into bentonite was successfully prepared by pillarization method, and was calling Bi-Oxides pillared clays. It has used to catalyst for ethanol to gasoline conversion. Basal spacing for bentonite and Sn-Cr/bentonite were 12,83Ǻ and 25,67Ǻ respectively. Specific surface area and pore volume of Sn-Cr/bentonite was investigated and appeared be bigger than bentonite. The results confirmed by BET analysis that were 30,35 m2/g become 168,86 m2/g and pore volume from 0,0065cm3/g become 0,03 cm3/g. The thermal stability was determined by Thermogravimetry Analysis from temperature 0ºC until 1000ºC and the functional group changes detected by Fourier Transform Infra Red. XRF and EDX detected the Sn-Cr metals in the bentonite. The results of the liquid catalyst test analyzed by GC-MS and showed the contents consisted of benzene, toluene, octane, and naphthalene, that were similar with commercial gasoline. So, the Sn and Cr were using as metal pillars for bentonite interlayer and successfully used this Bi-oxides pillared clays for ethanol to gasoline conversion. Keywords— Bi-Oxides, Pillared clays, Sn-Cr/Bentonite, Ethanol to Gasoline.

Natural fibers made into cellulose have attracted interest in the research and development of composite materials in recent years. One of them is Kenaf fiber from Sumberejo, East Java. The Kenaf fiber nanocellulose reinforced polyurethane (NC-PU) composites were prepared via in-situ polymerization. The purpose of this research is to analyze the thermal properties and morphology of PU and NC-PU composites. Then, TGA (thermogravimetric analysis), DTG (differential thermogravimetric analysis), DSC (differential scanning analysis) and SEM (scanning electron microscope) are applied to characterize PU and NC-PU composites. The addition of nanocellulose up to 7 wt.% in polyurethane was found to decrease the melting temperature of NC-PU composites and decrease the rate of decomposition. The lowest decomposition rate is attributed to the composite material of 10 wt.% NC-PU, which has a decomposition rate of 1.7 %/min, and the highest residual decomposition rate of 67 %. The addition of nanocellulose to PU also decreases the average pore size of NC-PU composites

Bentonite is material from soil and has unique properties. Because of these properties, bentonite has been exploited widely for different utilization. Bentonite has a simple structure that collapses at elevated temperatures. Then, it was required to prepare zirconia to be pillared with high surface area and particular active site. Ultrasonic treatment was an alternative technology for preparation of zirconia pillared bentonite. Modified of structure and surface active site with variable condition ultrasonic on power output (30%, 50%, 70%) with 20 kHz and 20 minutes preparation of zirconia pillared bentonite were studied using by X-Ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), chemisorption and Nitrogen gas sorption technique. The results were confirmed that the presence of polycation zirconium under ultrasonic indicated an increase in the basal spacing from 14.93 Å to 19.42 Å and 10 times increase of specific surface area from 25.150 m2/g to 265.076 m2/g. It was confirmed that ultrasonic treatment with three type variations caused significant change in the structure of bentonite and obtained the highest increase in surface area. Activity of catalytic provided an effective and efficient conversion on the esterification reaction. Finally, it was found that the higher power output ultrasonic treatment at 70% of power output resulted in partial damage of the pillar bentonite.

Pineapple leaf fiber (PALF) is one of natural fibres that has high cellulose content. However, pineapple plants must be replaced with new plants once it is harvested, leaving the leaves as waste. In this research, the isolation and characterization of Subang based PALF were conducted. Chemical pre-treatments including alkaline treatment with Sodium Hydroxide and bleaching to remove nanocellulosic constituents such as lignin and hemicellulose were conducted. This process was followed by mechanical treatment using ultrafine grinder to produce cellulose nanofiber (CNF). Transmission Electron Microscopy (TEM) images showed that the CNF had 45-75 nm in diameters. The percentage crystallinity was determined by X-ray diffraction (XRD). The crystallinity values of raw PALF, treated PALF, and CNF were 74.97%, 76,29%, and 69.52% respectively. Fourier Transform Infrared (FTIR) spectroscopy analysis was carried out to investigate the chemical structure changes after both chemical and mechanical treatments. The presence of a peak that related to cellulose confirmed that the process was well conducted. These results indicated that PALF waste could become added value to agricultural waste and expected to become reinforcement agent in nanocomposite for structural application since PALF had low aspect ratio and had high percentage crystallinity values.

Bamboo fibers have been used for reinforcements in structural composites because of their environmental friendly properties. The purpose of this study was to investigate the characteristics of three types of bamboo, namely Tali bamboo, Gombong bamboo and Haur Hejo bamboo to meet the requirements for a reinforcement in structural composites. The three types of bamboo fibers were alkaline treated by varying the concentrations of NaOH (4% and 6%), and immersion times (1, 2, and 3 hours). The alkaline pre-treatment was conducted at the temperature of 120°C and the pressure of 0.5 MPa using a steam explosion method. The treated bamboo fibers were characterized by FTIR and measured their tensile strengths. The tensile test results showed that the tensile strengths of Tali, Gombong, and Haur Hejo bamboss were 710 MPa, 418 MPa, and 457 MPa respectively. Whereas, the FTIR analysis indicated that there was still a peak of lignin with small intensity marked by aromatic C = C (alkyne) at the wavelength of 1500-2600 cm−1 for all types of bamboo. There was also a peak of cellulose with an increase in the intensity marked by the aromatic group C = H (alkene) at the wavelength of 1900-2400.

Currently, the development of plastics that can be easily decomposed is attracting attention, especially for the conversion of polymer-based materials such as modified polyvinyl alcohol (PVA) into composites. Bio-nanocomposites were prepared using the solvent casting method of PVA and organoclay as the matrix and nanofiller, respectively. In this study, the characteristics and mechanical properties of the PVA/hexadecyltrimethylammonium bromide (C16)-intercalated organoclay nanocomposite were examined. This study was carried out in two stages, i.e., the interactions between organoclay and C16 and the synthesis and characterization of the PVA/organoclay-CI6 nanocomposites. Intercalation was verified from the shift of the X-ray Diffraction (XRD) peak from 2θ = 6° to 4.9° of bentonite and organoclay, with a shift in the basal spacing from 15.1 to 19.7 Å. The highest tensile strength of 58.02 MPa was observed for pristine PVA, and the lowest tensile strength of 41.33 MPa was observed for the PVA/organoclay–7% C16 nanocomposite. The highest water vapor transmission rate of 0.35 g/m2/h was observed for the PVA/organoclay–7% Cl6 nanocomposite, and the lowest value of 0.62 g/m2/h was observed for pure PVA. PVA/organoclay–3% C16 exhibited the optimum, as well as the least, decomposition properties, and PVA exhibited natural decomposition.

The development of natural fiber reinforced composite research has shown significant results. Pineapple leaf fiber reinforced composites for non-structural application provide added value for Subang pineapple leaf fiber (PALF) waste. This study aimed to observe flexural strength, water absorption and desorption of composites which referred to the Indonesian National Standard (SNI) for composite board. Alkali treatment on Subang PALF was performed to improve the interface bonding between PALF with polypropylene (PP), in which the PALF was soaked in 5% NaOH solution for 24 hours. Treated PALF and PP sheets were fabricated using compression molding (hot press) technique with the variation of fiber fraction to polypropylene were 20 wt%, 30 wt% and 40 wt%. Flexural property, desorption and absorption water tests were conducted on PP and PP/PALF composites, and Optical Microscope (OM) observation was performed on the surfaces after the flexural test was conducted. The highest flexural strength and flexural modulus were (4.89 ± 0.37) MPa and (1.13 ± 0.43) Mpa respectively, these values shown an increased respectively by 153,37% compared to the pure PP. Then the desorption and the absorption water tests-were (1.08 ± 0,12) % and (8,83 ± 3,35) % respectively. The morphology of flexural tested composites indicated that matrix failure; and it showed that there was a strong interface bonding between the fiber and matrix.

This work is aimed to clarify the effect of formation voltage on the pore size of porous anodic aluminum oxide (PAAO) layer formed on commercially pure aluminum. The PAAO layers were obtained by anodization process in 0.3 M sulfuric acid solution at constant voltages of 10, 15, 20, and 25 V at 10°C. The structure and morphology of PAAO layers were characterized by using FE-SEM. The pore diameters which were estimated by using ImageJ software were 19.61 + 15.35 nm, 20.03 +13.59 nm, 20.31 + 12.36 nm, 25.06 +12.10 nm, and the wall thicknesses were 33 nm, 49.99 nm, 74.97 nm, 83.33 nm for the PAAO formed at 10, 15, 20 and 25 V, respectively. The structure of the porous oxide layer became more uniform and organized, and the diameter of the pores increased linearly with applied voltage. High anodization voltage is known to cause Joule heating because of the fast movement of electrons and ions. It is believed that the Joule heat was transferred to the bulk electrolyte which results in larger pore diameter and interpore distance. The optimum condition to obtain high order PAAO is at 25 V.

Kenaf fiber can be used as an alternative to synthetic fiber reinforcement in composites. This research was conducted in order to determine the flexural and diffusion properties of the composite by varying the fiber fractions. Before being used as a reinforcement, kenaf fiber was firstly treated with alkali treatment in NaOH solution for 24 hours. Polypropylene and kenaf fibers were fabricated with a hot press machine. The fiber fractions were 30 wt%, 40 wt%, 50 wt%, and pure polypropylene samples were also fabricated as a comparison. The highest flexural strength, the minimum water absorption and water content were found in the polypropylene/30 wt% kenaf fibre composites with the value of (4.77 ± 0.799) MPa, (3.61 ± 0.823)% and (0.192 ± 0.154)% respectively.

The use of natural fibers to substitute synthetic fibers on composites has been an interest to be developed. Kenaf is a plant that abundant in Indonesia because it‘s adaptive and its fiber has good strength. The purpose of this study was to determine the value of impact resistance, flammability, and hardness of polypropylene / unidirectional Sumberejo kenaf fiber composite boards in accordance with Standar Nasional Indonesia (SNI). Composites were fabricated by the variation of fiber, which were 30 wt%, 40 wt%, and 50 wt%. Pure polypropylene samples were also fabricated for comparison. The fabrication used a compression molding method. The best results were obtained from polypropylene / 50 wt% kenaf fiber composites with impact energy, flammability, and hardness values were (47.54 + 10.7) J / cm2, (7.1±5.1) mm / minute, and (66 + 0.8) HD respectively. Optical microscope observation on the impacted surface was a destruction of the matrix-fiber bonding and fiber breakage, in which showed the energy of impact was absorbed by kenaf fiber. The observation on the burned surface was burnt kenaf fibers and rest of PP that bonding with kenaf fiber, this indicated the kenaf fiber acted as an oxygen barrier.

Calcium phosphate can exist as several phases including hydroxyapatite (HA) and β-tricalcium phosphate (βTCP). Both HA and βTCP are chemically similar to calcified tissue, resulting in high incompatibility. In this study, we investigated the effects of heat treatment temperature (800 °C and 900 °C) and atmosphere (ambient air and argon) on the morphology, crystalline structure, and functional groups of calcium phosphate powder. Calcium phosphate without heat treatment was evaluated for comparison. The powders were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, and transmission electron microscopy. Under both atmospheric conditions, the effect of heat treatment at 800 °C led to the formation of both HA and βTCP, which was caused by the reduction of CO/- bond in calcium phosphate. In contrast, the heat treatment of calcium phosphate at 900 °C generated C−H and C=O groups, resulting in βTCP alone.

Several studies exhibit that high calcium intake prevents osteoporosis-related bone loss. In this study, the dietary effects of nano-tricalcium phosphate (n-CaP) and hydrolyzed collagen (HC) against bone loss at the peak of the bone growth stage are examined, and the main objectives are to prevent osteoporosis and to induce bone formation. The Sprague Dawley mice (Rattus norvegicus) is observed to be calcium deficient (the average calcium content of serum is ≤ 8%). The mice were randomized into four groups (P1: normal purified diet, P2: HC purified diet, P3: n-CaP purified diet, and P4: n-CaP and HC purified diet). After four weeks, all the groups were euthanized, and their bone formation was analyzed. UV-Vis analysis revealed that the calcium content values were 8.20 (P1), 8.92 (P2), 9.2 (P3), and 10.35 (P4) mg/dL, respectively. The corresponding values obtained by the atomic absorption spectrophotometric analysis are 72.29 (P1), 74.25 (P2), 74.80 (P3), and 76.04 (P4) w/w% respectively. To assess the spinal calcification, the infrared spectra were recorded. The splitting factors were 2.5 (P1), 2.6 (P2), 2.5 (P3), and 2.6 (P4), indicating better absorption of n-CaP for P4. Hence, n-CaP and HC-purified diets are suitable to ensure bone growth.

The study aimed to describe the alkaline treatment advantage to remove ash component from natural rice straws. Most of the ash component in the rice straw is silica. High ash content is particularly harmful to cutting tools and to chemical to recovery systems in the pulp paper industry. In this study, the silica content has been removed simply through by immersion process in the 5% sodium hydroxide solution to obtain de-silicated rice straw. The study revealed the effectiveness of this alkaline process and the compatibility in commercial practice. The rice straw pulping is considered competitively to complement the global demand of raw material in paper production. Therefore, the treated rice straw plays an important role in providing raw material in the form of wood and rice straw blend feedstock for pulp and paper industry.

Plastics as packaging materials and coatings undergo increasing demands globally each year. This pose a serious problem to the environment due to its difficulty to degrade. One solution to addressing the problem of plastic wastes is the use of bioplastics. According to the European Organization Bioplastic, one of the biodegradable plastics is derivative of cellulose. To improve mechanical properties of bioplastic, biocomposites are made with the addition of certain additives and fillers. The aim of this study is to investigate the effect of butyl benzyl phthalate plasticizer (BBP) and ZnO nanoparticles addition on mechanical properties of cellulose acetate butyrate (CAB) / organoclay biocomposite. ZnO nanoparticles synthesized from commercial ZnO precursor by using sol-gel size reduction method. ZnO was dissolved in a solution of citric acid in the ratio 1:1 to 1:5 to form zinc citrate. Zinc citrate then decomposed by calcination at temperature of 600oC. ZnO nanoparticles with an average size of 44.4 nm is obtained at a ratio of 1: 2. The addition of ZnO nanoparticles and BBP plasticizer was varied to determine the effect on the mechanical properties of biocomposite. The addition of 10 – 15 %wt ZnO nanoparticles and 30 – 40 %wt BBP plasticizer was studied to determine the effect on the tensile strength, elongation, and modulus elasticity of the biocomposites. Biocomposite films were made by using solution casting method with acetone as solvent. The addition of plasticizer BBP and ZnO nanoparticles by 30% and 10% made biocomposite has a tensile strength of 2.223 MPa.Plastics as packaging materials and coatings undergo increasing demands globally each year. This pose a serious problem to the environment due to its difficulty to degrade. One solution to addressing the problem of plastic wastes is the use of bioplastics. According to the European Organization Bioplastic, one of the biodegradable plastics is derivative of cellulose. To improve mechanical properties of bioplastic, biocomposites are made with the addition of certain additives and fillers. The aim of this study is to investigate the effect of butyl benzyl phthalate plasticizer (BBP) and ZnO nanoparticles addition on mechanical properties of cellulose acetate butyrate (CAB) / organoclay biocomposite. ZnO nanoparticles synthesized from commercial ZnO precursor by using sol-gel size reduction method. ZnO was dissolved in a solution of citric acid in the ratio 1:1 to 1:5 to form zinc citrate. Zinc citrate then decomposed by calcination at temperature of 600oC. ZnO nanoparticles with an average size of 44.4 nm i...

Clay minerals have received considerable attention in the last years because of their environmental compatibility, low cost, high selectivity, and operational simplicity. Although clays are very useful for many application in the field of catalysis, they have main disadvantage: their lack of pore volume and spesific surface area. Porosity and stability of these materials are improved by pillaring the clay layers with SnCl4, which leads to materials known as pillared clays (PILC). This research aims were to characterize the Bentonite and Sn-Bentonite as catalysts for cracking and oligomerization. The Sn-Bentonite was prepared by pillarization method with a variation in metal ratio of 5 mmol dan 10 mmol.gr−1 of bentonit. The catalyst characterized by X-ray Diffraction, X-ray Fluorescence, Fourier Transform Infra Red, Brunauer Emmett Teller, Thermogravimetric Analysis. The results showed that the Sn-Bentonite catalyst had large basal spacing and good porous structure, and the specific surface areas increased. XRF detected the Sn in the Bentonite and TGA results showed the ability Sn-Bentonite in receiving heat. FTIR test showed two type of acidity, broansted and lewis acid. The characterized results indicated that Sn-Bentonite with metal ratio 5 mmol.gr−1 better than Sn-Bentonite with metal ratio 10 mmol.gr−1, in which there was a significant increase the basal spacings, specific surface area, and pore volume. The TGA results for Sn-Bentonite appeared to be more thermally stable than Bentonite.

In this research, we studied how the nano Ca3(PO4)2 uptake in bone mineral influenced Rattus norvegicus (Sprague Dawley) calcium deficiency status. Association of Official Analytical standard method was used for proximate analysis, meanwhile calcium and magnesium compositions were determined by atomic absorption spectrophotometry. In addition to that, ultraviolet spectrophotometry and fourier transform infrared were used to determine the content of phosphorus and infrared spectrum of transmittance, respectively. The results showed that administration of nano-sized Ca3(PO4)2 purified diet gives a higher uptake than the regular-size, suggesting that the application of nano Ca3(PO4)2 to rats suspected in a bone mass peak age with calcium deficiency may potentially prevent the occurrence of osteoporosis.

Organo layered silicates (OLS) were successfully synthesized from Tapanuli clay through an intercalated ultrasonic method using hexadecyltrimethylamonium bromide ( HDTMABr ) as a cation exchange agent. Tapanuli clay–epoxy nanocomposites were also successfully synthesized with an in-situ polymerization. X-Ray Diffraction and Transmission Electron Microscope (TEM) results demonstrated a pattern of clay morphology typically found in nanocomposite systems. Although the nanocomposites' diffractogram showed an exfoliation structure, the TEM findings confirmed that the OLS d -spacing is between 2.58 nm (the minimum value) up to 14.74 nm (the maximum value); which indicates the nanocomposites posses a mixed structure between intercalated and exfoliated structures. It was found that the presence of 1wt% Tapanuli organo clay in the epoxy systems provides higher stiffness and higher Heat Deflection Temperature by 30 % and 7 % respectively.

Incorporating multi wall carbon nanotube (MWCNT) into the polymer can improve the electrical properties of the nanocomposites. The effects of MWCNT on the electrical and rheological properties of polypropylene/MWCNT (PP/MWCNT) nanocomposites are investigated. The nanocomposites were prepared using melt mixing technique at chamber temperature of 180°C and rotor rotation of 100 rpm for 10 minutes. Addition of MWCNT increases the electrical surface conductivity up to 10 −7 S. The electrical percolation threshold of the nanocomposites is found to occur at 1.3 wt% MWCNT content. Viscosity of the nanocomposites increased with the addition of MWCNT. The rheological percolation threshold of the PP/MWCNT is found occur at 1.4 wt% MWCNT content. Well dispersion is observed by mean Scanning Electron Microscope (SEM) analysis.

Heterogeneous catalysts hold various advantages, namely, easy to separate from their products, reusable and regarded as environmental friendly materials. The synthesis of immobilized Ni monometallic, Co monometallic and Ni-Co bimetallic by Tapanuli clay were carried out using intercalation method. Firstly, the synthesis of Na-Bentonite was conducted to provide sufficient area to immobilize bimetal in the clay interlayer. Secondly, Ni, Co and Ni-Co were immobilized in the Tapanuli clay interlayer. Several techniques, such as X-Ray Diffraction, Fourier Transform Infra Red and Energy Dispersive X-Ray Analysis were applied to characterize and compare the properties of the synthesized materials. The results showed that the insertion of Ni, Co and Ni-Co in the clay interlayer occurred through a cation exchange reaction. The Energy Dispersive X-Ray analysis for Ni-Co bimetallic showed that the immobilized Ni and Co in the clay is in the ratio of 1:1. Catalytic test with Gas Chromatography showed that Ni-Co bimetallic generates a higher yield percentage compared to Ni and Co monometallic.

This work investigates the fatigue behaviour and the mechanism of fatigue failure of an epoxy resin with a dispersion of modified layered silicates in the polymer matrix. The fatigue properties are very important for structural application of nanocomposite materials. Clay-epoxy nanocomposites were successfully synthesized with a commercially available 1-Methylimidazole curing agent. The XRD and TEM findings demonstrated a pattern of clay morphology typically found in nanocomposite systems. The fatigue performance and fatigue failure mechanism of the clay-epoxy materials were studied under repetitive bending loads. The results showed that the fatigue life of filled epoxy improved significantly at strain amplitudes below a threshold value. The E-SEM observations of the epoxy and the clay-epoxy fracture surfaces showed different patterns. In conclusion, the addition of silicate strongly determines the fracture mechanism and enhances the fatigue performance.

This paper presents an investigation of the possibility of improving the fatigue properties of an epoxy resin through dispersion of modified layered silicates within the polymer matrix. Montmorillonite-epoxy nancocomposites were successfully synthesized with a commercially available 1-Methylimidazole curing agent. The morphology of these materials was investigated by XRD and TEM. The findings demonstrated a pattern of clay morphology typically found in nanocomposite systems. Four point loading measurements showed an increase in modulus for 2.5 wt% and 10 wt% clay contents when compared to the unfilled epoxy, whereas the moduli showed a decrease for 5 wt% and 7.5 wt% clay contents. This behavior is typical for most particulate-filled systems. Fracture surfaces were examined using an E-SEM. The failure mechanism of the nanocomposites varied from that of the unfilled epoxy. Below a critical strain amplitude, the fatigue life of the filled epoxy improved significantly compared to that of the unfilled epoxy. In conclusions, the addition of silicates changes the fatigue failure mechanism and improves significantly the fatigue life.

Mechanical Enhanced Oil Recovery (EOR) through chemical injection is using an anionic surfactant to improve the recovery of oil residues, particularly in a reservoir area that has certain characteristics. This case led the authors to conduct research on the synthesis of an anionic surfactant based on oleic acid and polyethylene glycol 400 that could be applied as a chemical injection. In this work, we investigate the sulfonation of Polyethylene glycol oleate (PDO) in a sulfuric acid agent. PDO in this experiment was derived from Indonesian palm oil. Variation of mole reactant and reaction time have been studied. The surfactant has been characterized by measuring the interfacial tension, acid value, ester value, saponification value, iodine value, Fourier Transform Infrared (FTIR), and particle size analyzer. There is a new peak at 1170-1178 cm-1 indicating that S=O bond has formed. PDO sulfonate exhibits good surface activity due to interfacial tension of 0,003 mN/m. Thus, polyethylene glycol oleate sulfonate was successfully synthesized and it could be useful as a novel an anionic surfactant.

Composite solid propellants experience aging process during storage, and their properties will alter. The stabilizer added was used to reduce the effects of aging. This research studied the influence of the stabilizer on changes of the composite solid propellant thermal decomposition due to the onset of aging during the 40 days of storage at a temperature of 333 K. AO 2246 as a stabilizer added by as much as 0 to 1% by weight of propellant binders. The testing method used is heating the samples at various heating rate using DSC. And the Ozawa method was used to determine the values of the activation energy and frequency factor on the Arrhenius parameters. The optimal composition of stabilizer was 0.5 wt% for those on the value of activation energy and frequency factors for unaged and aged propellants were nearly the same i.e. 196 kJ/mol and 1.22 x1012 min-1.

The use of synthetic fibers as reinforcement in composites has disadvantage which are unsustainable and an adverse impact on the environment. An alternative reinforcement for composites is natural fiber. Polypropylene and Sumberejo kenaf fibers were used respectively as the matrix and reinforcement. The aim of this research was to obtain the optimum tensile properties and deflection temperature with the variation of kenaf fiber fractions. Polypropylene/kenaf fiber composites were fabricated by hot press method. The kenaf fiber was soaked in NaOH solution before being used as the reinforcement and polypropylene was extruded before being used as the matrix. The weight fractions were varied to produce composites and pristine polypropylene samples were also prepared for comparison. The optimum tensile strength, modulus and deflection temperature were found in the composites with the 40 wt% kenaf fiber fraction with an increase up to 80% and 170% compared to the pristine polypropylene with the values of (60.3 ± 4,3) MPa and (159.1 ± 1,8) °C respectively. The Scanning Electron Microscope observation results in the fracture surface of the composites with the 40 wt% fiber fraction showed a relatively good bonding interface between fibers and the matrix and the failure modes were fiber breakage and matrix failures.

The development of eco-friendly composites has been increasing in the past four decades because the requirement of eco-friendly materials has been increasing. Indonesia has a lot of natural fiber resources and, pineapple leaf fiber is one of those fibers. This study aimed to determine the influence of weight fraction of pineapple leaf fibers, that were grown at Subang, to the tensile properties and the deflection temperature of polypropylene/Subang pineapple leaf fiber composites. Pineapple leaf fibers were pretreated by alkalization, while polypropylene pellets, as the matrix, were extruded into sheets. Hot press method was used to fabricate the composites. The results of the tensile test and Heat Deflection Temperature (HDT) test showed that the composites that contained of 30 wt.% pineapple leaf fiber was the best composite. The values of tensile strength, modulus of elasticity and deflection temperature were (64.04 ± 3.91) MPa; (3.98 ± 0.55) GPa and (156.05 ± 1.77) °C respectively, in which increased 187.36%, 198.60%, 264.72% respectively from the pristine polypropylene. The results of the observation on the fracture surfaces showed that the failure modes were fiber breakage and matrix failure.

Jute is one of eco-friendly natural fiber with relatively low cost and high volume production. This study aimed to determine the effect of weight fractions of jute fiber as a reinforcement in polypropylene (PP) to obtain an optimum properties of PP/jute fiber composites. Jute fiber was pre-treated through alkalization. The PP was initially produced by extrusion process, followed by fabricated the composites by compiling the PP matrix and jute fibers into lamina using a hot-press method. The results of tensile test and heat deflection temperature test showed that the addition of 40wt% jute fiber to the PP increased the tensile strength about 19.7 % up to (38.2±4.9)MPa, the Young modulus about 79.8 % up to (3.20±0.26)GPa, and the heat deflection temperature about 143% up to (143.3±1.14)°C compared to pristine PP. Based on Scanning Electron Microscopy observation on the fracture surfaces, it was shown that the mode of failure on the composites failure surfaces was "fiber pull-out", which due to the poor interface bond between the fiber and the matrix.