Jusami | Indonesian Journal of Materials Science
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SYNTHESIS AND CHARACTERIZATION OF LiFePO4/PPy/CLAY COMPOSITE AS CATHODE MATERIAL FOR Li-ION BATTERY
Get PDFSYNTHESIS AND CHARACTERIZATION OF LiFePO4/PPy/CLAY COMPOSITE AS CATHODE MATERIAL FOR Li-ION BATTERY. Conductor polymers have been used previously as a conducting agent or carbon source in various sol-gel and solid state methods to increase the conductivity of LiFePO4. The composite of LiFePO4/PPy/Clay were synthesized by mixing LiFePO4 and clay with a Ppy solution. The characterizations were done by using X-Ray Diffractometer (XRD), Scanning Electron Microscope (SEM) and LCR meter respectively. From XRD analysis it could be deduced that LiFePO4 has an ordered olivine structure with a Pnma space group. The SEM images provide clear evidence that small crystal particles of LiFePO4 either coat the surface of the clay particles or lie among them. These LiFePO4 particles have a small particle size (100–500 nm). With the increasing of LiFePO4 content, these small crystal particles at the surface or among the clay particles are increased. Increasing the PPy content to increase the conductivity of the material obtained. With the addition of clay from 5 to 10 wt. %, the DC conductivity of the blends is clearly observed to increase up to three orders of magnitude
PROPERTIES OF EDIBLE FILM FROM MODIFIED SAGO STARCH PRECIPITATED BY BUTANOL
Get PDFROPERTIES OF EDIBLE FILM FROM MODIFIED SAGO STARCH PRECIPITATED BY BUTANOL. The edible film is a thin layer that can be used as food packaging and safe for consumption. Starch is a material that can be used as an edible film because it is biodegradable, non-toxic, able to form a strong and transparent film. In this research, sago starch has been precipitated using butanol for 1, 2, 3, 4, and 5 hours. Precipitated sago is reacted with 3% glycerol and then formed into a film by printing it on a petri dish. Characterizations of edible films are FTIR, contact angle, water solubility, swelling power, WVTR, and mechanical properties (thickness, tensile strength, and elongation). Edible film (B2) has the best mechanical properties, that is high hydrophobicity (contact angle is 60,351 degree), tensile strength (6,8843 N/mm2), and elongation (49,5081 %), also low water solubility (0,3352 %), moisture content (18,6005 %), and WVTR (0,02986 g s-1 m-2)
Study of Microstructural and Corrosion Properties of Aluminium Alloy 7075 after Plasma Nitriding
Get PDFPlasma nitriding is a treatment process of metals by depositing nitrogen into metal that considered to be nitrided by mean of increasing the mechanical, physical, and chemical properties of the metal. This treatment will form a hard layer compund of Al-N on the surface of the sample. In this study, aluminium alloy 7075 was nitrided which the application of it to structural part of aircraft makes it vulnarable to not only corrosion and wear attack but also decreasing the hardness of the material. One method to overcome these issues is plasma nitriding. The purpose of of this research is to do the characterizations of plasma nitrided aluminium alloy 7075 regarding its microstructure, mechanical, and chemical properties. The characterizations that had been done were microhardness Vickers testing, SEM-EDX, and electrochemical corrosion testing Potensiostat. The hardness of the sample increased 55% from 75,88 VHN (raw material) to 117,68 VHN (at optimum parameter). The depth of the white layer of plasma nitriding is approximately 6 µm, while the EDX result reported carbon, oxygen, and nitrogen presence. Corrosion testing showed that the highest corrosion rate is on the raw material, 0,15393 mpy. While the optimum one is 0,07184 mpy
MICROWAVE-ASSISTED CENTRIFUGAL SPINNING OF GELATIN MICROFIBERS
Get PDFMICROWAVE-ASSISTED CENTRIFUGAL SPINNING OF GELATIN MICROFIBERS. Herein, we disclose a method for preparing polymeric microfibers. According to an embodiment of the method, gelatin fibers were prepared from 50% aqueous gelatin solution by centrifugal spinning. The produced material feels similar to wool to the touch. Average fiber diameter was determined to be 40 m. Thermal stability of the material is similar to that of gelatin fibers prepared by other techniques, e.g. electrospinning. Elastic modulus of the fibrous material was determined to be 230 MPa and its toughness was found to be 160 kJ/m3. The described method is one of the fastest low-cost lab-scale fiber production techniques available (as a practical example, the speed of fiber production was roughly 5 g/s) and could be used to prepare various polymeric fibers in an eco-friendly way for a wide range of applications, including textile industry, tissue engineering and drug delivery
THE UTILIZATION OF PET WASTE AS RAW MATERIAL FOR PRODUCING MONOFILAMENT YARN : THE EFFECT OF WINDING SPEED ON THE PHYSICAL AND MECHANICAL PROPERTIES OF THE YARN
Get PDFTHE UTILIZATION OF PET WASTE AS RAW MATERIAL FOR PRODUCING MONOFILAMENT YARN : THE EFFECT OF WINDING SPEED ON THE PHYSICAL AND MECHANICAL PROPERTIES OF THE YARN. Plastic waste production in Indonesia is quite high, reaching 15% to the total national waste production or 189-kilo tons/day with an average growth of 14.7% per year, the second biggest contributor after organic waste. This fact greatly affects human health and the environment since plastic is difficult to degrade, estimated to require 100 to 500 years for the plastic to decompose completely. Therefore, recycling becomes a popular solution to reduce waste or plastic waste by turning it into new products that have added value. Plastic materials, such as PET, have thermoplastic properties which become a special potential to use as recycled materials. The aim of this research was to study the ability of PET plastic waste as a raw material for making monofilament yarn by melt-spinning methods. PET plastic waste is melted at 250-260 °C, then is extruded using a prototype melt-spinning tool with a single spinneret hole which the diameter is 3 mm into a monofilament yarn using three variations of winding speed (a) 43.33 m/min, (b) 59.35 m/min and (c) 72.72 m/min The results showed that the yarn with the highest winding speed (variation C) produced yarn with the highest fineness, reaching (30.06± 4.82) denier, and the best tensile strength compared with the other, reaching (47.7±14,97) MPa with elongation of of (10± 9.65) %
PREPARATION OF ACYCLOVIR-ISONICOTINAMIDE COCRYSTAL BY SOLVENT EVAPORATION METHOD WITH METHANOL AND ISOPROPANOL
Get PDFPREPARATION OF ACYCLOVIR-ISONICOTINAMIDE COCRYSTAL BY SOLVENT EVAPORATION METHOD WITH METHANOL AND ISOPROPANOL. Acyclovir is a nucleoside synthetic analog antiviral group used in the treatment of Herpes simplex virus (HSV-1 & HSV-2) and Varicella zoster virus (VZV). Acyclovir has low water solubility, so it needs to be modified in the form of cocrystal with isonicotinamide. This study aims to obtain the physical characteristics produced by acyclovir-isonicotinamide cocrystal (1:1) made through the solvent evaporation method with methanol and isopropanol. The crystalline formed is characterized by DSC, PXRD, FT-IR and SEM. The characterization results showed the presence of new crystals that formed between acyclovir-isonicotinamide in methanol and isopropanol solvents. Thermograms showed sharp exothermic peaks at 183.31°C and 186.24°C. The diffractogram showed a new peak at 2θ = 5.19 and 5.82. The spectrum showed a shift in wavelength in the cocrystal formed. The cocrystal has a different morphology compared with parent drug and coformer on analysis using SEM. This research shows that acyclovir can form cocrystal with isonicotinamide by solvent evaporation method with methanol and isopropanol
THE EFFECT OF ADSORBENT TYPE AND RATIO ON REMOVAL AND ISOTHERM ADSORPTION OF METHYLENE BLUE
Get PDFTHE EFFECT OF ADSORBENT TYPE AND RATIO ON REMOVAL AND ISOTHERM ADSORPTION OF METHYLENE BLUE. Methylene Blue (MB) is one of the dye that are widely used in the textile industry. The wastewater from textile industry that contain MB can reduce the oxygen level in water bodies. This study aims to determine the efficiency of the adsorbent in MB removal and to analyze the isotherm adsorption. The variations conducted in this research was the type of adsorbent and its ratio. The activated carbon that used as adsorbent was fresh betel nut (Cyrtostachys lakka) activated carbon (A), regenerated betel nut activated carbon (B), and coconut shell activated carbon (Cocos nucifera) (C). The type of adsorbent was AB, AC, and BC with ratio of 1:1, 1:2, 1:3, 2:1, and 3:1. The MB concentration was analyzed by using UV-Vis spectrophotometer. Isotherm adsorption was calculated based on Freundlich and Langmuir. The best results showed that the combination of fresh and regenerated betel nuts (AB) with ratio of 3:1 can remove 97.77% of MB. The adsorption process of MB in aqueous solution followed the Langmuir model with regression over 0.99 and adsorption capacity in the range of 2.14 mg/g - 3.53 mg/g