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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.

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.

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

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.

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.

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...

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.

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.

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.

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.

Comparative Studies on Mechanical Properties of As-received and Recycled Polypropylenes Characteristic of Pure and Recycled Polypropylene. In this study, the mechanical properties and the fracture areas of as-received, recycled, and commercial recycled Polypropylenes (PPs) used for cloth hanger materials were compared. Differential Scanning Calorimetry (DSC) test results showed that recycling process did not cause a significant change to the material’s melting point, which stayed in a range of 160-163 o C. Meanwhile, Fourier Transform Infrared (FTIR) test results showed that the commercial recycled PPs contained of polyethylene (PE), which was not found in the asreceived and recycled PPs. Tensile and hardness tests demonstrated that there were no significant differences between the as-received and recycled PPs. In contrast, tensile test results of the commercial recycled PPs showed that the tensile strength, Young modulus and strain-at-break were lower than those of the as-received PPs by 22.1%, 8.1% and 65.7% respectively. The hardness test results of the commercial recycled PPs showed that the recycling process had a little effect on the material’s hardness. These facts were supported by Scanning Electron Microscope (SEM) observation on the surface that the contour of the commercial recycled PPs was relatively flatter and had smaller grain size than those of the as-received PPs. This indicated that the commercial recycled PPs were more brittle compared to the recycled PPs. To conclude, the recycled PPs have similar properties to the as-received PPs so that recycled PPs are suitable to be applied as cloth hanger application.

Clay-epoxy nanocomposites were synthesized from DGEBA resin and montmorillonite clay with an in-situ polymerization. One type of untreated clay and two types of organo clay were used to produce the nanocompsoites. The aims of this study were to examine the nanocomposite structure using different tools and to compare the results between the unmodified clay and modified clays as nanofillers. Although diffractogram in reflection mode did not show any apparent peak of both types of materials, the transmitted XRD (X-Ray Difraction) graphs, DSC (Differential Scanning Calorimeter) analysis and TEM (Transmission Electron Microscope) images revealed that the modified clay-epoxy and unmodified clay-epoxy provides different results. Interestingly, the micrographs showed that some of the modified clay layers possessed non-exfoliated layers in the modified clay-epoxy nanocomposites. Clay aggregates and a hackle pattern were found from E-SEM images for both types of nanocomposite materials. It is shown that different tools should be used to determine the nanocomposite structure.

Linear low density polyethylene‐Tapanuli organoclay‐pineapple fiber composites were succesfully synthesized by a melt intercalation method. The clay was modified as an organoclay by a cation exchange reaction using hexadecyl trimethyl ammonium bromide (HDTMABr) surfactant. The X‐ray diffraction results of the organoclay exhibited a higher basal spacing of 1.87 nm compared to the unmodified clay of 1.46 nm. The composite tensile strength was enhanced up to 46.4% with the 1 wt% organoclay addition. Both tensile and flexural moduli increased up to 150.6% and 43% with the 3 wt% organoclay addition to the composites. However, the flexural strength of the composites was not improved with the organoclay addition. The addition of organoclay has also decreased the heat deflection temperature of the composites.