Jurnal Sains Materi Indonesia

Front Matter (Editorial Team, Preface and Table of Contents)

2023-11-02T09:48:35+07:00

Synthesis and Characterization of LaF3:Ce Scintillator Material

2023-03-29T10:46:35+07:00

Synthesis and Characterization of LaF3:Ce Scintillator Material.Synthesis and characterization of the LaF₃:Ce scintillator have been carried out. Synthesis was carried out using the co-precipitation method. In this study, the raw materials used were NaF, LaCl₃•7H₂O, and Ce(NO₃)₃•6H₂O with ethanol and distilled water as a solvent; while surfactants were used oleic acid. In this study, the compound LaF₃:0.2Ce was synthesized. The sample was characterized by using an X-Ray Diffractometer (XRD), a Scanning Electron Microscope (SEM), and a Spectrofluorometer. The analyzed data showed that the 82.6 weight fraction of LaF₃:0.2Ce phase has precipitated accompanied by the formation of NaCl and C₂Ce phases of 5.1 and 12.3 weight fraction, respectively. The NaCl phase is a by-product of the chemical reaction: xLaCl₃•7H₂O + zCeCl₃•7H₂O + 3NaF → La_xCe_zF₃ + 3NaCl + 7H₂O which could be removed from the precipitate solution by an appropriate separation method, while the C₂Ce one appeared as a result of heating the sample at 400ºC. The LaF₃:Ce scintillator sample shows the phenomenon of a bluish glow with a lifetime, t = 6 × 10^-10 seconds even in the presence of a foreign phase. The existence of NaCl and C₂Ce as a local environment still makes LaF₃:0.2Ce has normal lifetime characteristics.

Effect of 2-Methylimidazole Composition as Low-Temperature Application in Phenol-Formaldehyde, Glycidyl Ether Epoxy Coating

2023-03-26T22:08:54+07:00

The addition of materials to pile pipe at low temperatures is very challenging. Thereby, an optimum operating level is needed to produce a quality coating. Furthermore, 2-methylimidazole (2MI) was added into a phenol-formaldehyde, glycidyl ether polymer fusion bonded epoxy (FBE) coating at different concentrations of 1, 2, and 3 %wt. Thermal analysis was then carried out using differential scanning calorimetry (DSC), where the addition of 2MI decreased the curing temperature to 134.76°C due to the reduced activation energy. Potentiodynamic polarization showed the best corrosion rate of 0.00991 mm/year with a current density of 0.847μA/cm2 after adding 1 %wt 2MI. Electrochemical impedance spectroscopy (EIS) was carried out to determine the charge transfer resistance and maximum coating capacitor capacitance after adding 1 %wt 2MI, namely 9.9 kΩ and 8.45×10-5 F, respectively. The cathodic disbondment test (CD-Test) showed that the disbondment radius of the coating under the influence of the cathodic protection current was 4.32mm. Mechanical analysis by pull-off adhesion test showed a value of 7.28 MPa after the addition of 2MI 2 %wt but decreased to 6.63 MPa at 3 %wt. Therefore, the optimum addition is 1 %wt 2MI for low-temperature applications of 170 –175°C in piles with high coating performance and compliance with predetermined standards.

Preparation of Polyurethane-Modified Epoxy Coating Materials Based on Vegetable Oil Derivated Ester

2023-03-30T11:55:54+07:00

This study utilize vegetable oil derivatives as a polyol in polyurethane. A modification of epoxy using polyurethane was done using ester derivative of vegetable oils as polyols, which was polyethylene glycol monooleate (PEGMO). The PEGMO was synthesized via an esterification reaction. The synthesis of polyurethane-modified epoxy using polyethylene glycol monooleate ester (PME-PEGMO) was conducted by reacting epoxy, tolonate and PEGMO. Analysis results of FTIR and H-NMR showed a new absorption peak derived from the urethane bond. The mechanical and thermal properties were characterized by a universal testing machine (UTM) and thermogravimetry analysis (TGA), respectively. According to the analysis results, it is shown that the addition of polyethylene glycol monooleate ester-based polyurethane on epoxy improved the mechanical properties of the epoxy, from 69.61 kgf/cm2 to139.80 kgf/cm2. However, it decreased the thermal stability of the epoxy. At 500°C, the mass of epoxy was remaining 28%, while the PME-PEGMO was only 13%.

Characterization of Glass Fiber / Epoxy with Various Silicone Resin Addition Composite’s Compressive and Flexural Strength

2023-08-10T22:16:26+07:00

Glass fiber/epoxy composite was developed and used widely in many
applications. Development on fiber and matrix of composite material was done to improve its
properties. Improvement of the composite’s matrix can be done/by adding a modifier. Silicone resin
is one kind of modifier that can be added to epoxy to improve its properties. Silicone resin will
improve the thermal stability of epoxy, but the effect on mechanical properties, especially when
combined with glass fiber, has not been done. In this study, a composite of glass fiber/epoxy with 0,
10, 20, and 30 weight-% silicone resin addition was tested by compressive and flexural loading
methods. Compressive strength and maximum strain tend to decrease with the increase of silicone
resin added. The highest compressive strength and strain were reached by a glass fiber and epoxy
composite without any modification at the value 240.63 MPa and 0.5%. Flexural strength will
decrease, but maximum strain will increase when more silicone resin is added to the matrix on the
flexural test. The biggest flexural strength at 293.73 MPa was possessed by the composite without
further modification, and a maximum strain of 5% was owned by the composite with 20% and 30%
silicone resin addition.

Porous Carbon Black Microsphere from Palm Oil Black Liquor

2023-05-23T16:47:28+07:00

The aim of this research is to synthesize porous carbon black microspheres from palm oil black liquor through an in-house spray pyrolysis system. The in-house spray pyrolysis (SP) system was developed using a horizontal furnace. To test the developed SP equipment, the temperature profiles within the developed spray pyrolysis chamber were examined at 3 different setting temperatures (800, 900, and 1000 °C). These temperatures were also applied for synthesizing the carbon black microspheres, with and without nitrogen as carrier gas. The morphology of carbon black produced by using SP equipment was tested by a 3D Optical Microscope and FE-SEM. The optimum temperature obtained in this study is 1000 ºC according to the characterization of carbon black microspheres produced. The FE-SEM analysis indicated the presence of spherical carbon having microstructures. This indicates that the in-house spray pyrolysis machine has been successfully developed for synthesizing carbon black microspheres.

Synthesis and Characterization of a Polystyrene-based Scintillator for Gamma Detection

2023-04-12T12:24:42+07:00

This study aimed to create and examine plastic scintillators made from a polystyrene matrix, which are widely used in radiation detection due to their favorable properties such as rapid decay time, low cost, resistance to moisture, and ease of fabrication. The scintillators were doped with p-terphenyl (PTP) and 1,4-bis[2-(phenyloxazolyl)]-benzene (POPOP) using an injection method with an extruder machine. The materials were then characterized using various techniques. Fourier Transform Infrared Spectroscopy (FTIR) revealed the presence of aromatic chains which are essential for the scintillation process. Differential Scanning Calorimetry (DSC) analysis showed stable thermal properties with a glass transition temperature of approximately 100ºC. Scanning Electron Microscopy (SEM) showed that the surface of the polymer is amorphous with small bumps and protrusions likely caused by the PTP and POPOP dopants. The optical evaluation indicated that the sample could absorb UV photons up to 340 nm and emit photons in the wavelength range of 400-500 nm with a peak at 421 nm. Gamma spectra analysis indicated that the plastic scintillators performed well in gamma detection and could be used in a Radiation Portal Monitor (RPM).

Post-Consumer Recycling of Polymers for Sustainable 3D Printing Filament Material

2023-05-12T13:23:08+07:00

3D printing technology is rapidly developing in the manufacturing industry in producing complex and easily adjustable three-dimensional objects using the help of controls from computers. Behind its advantages, the 3D printing process requires filaments from virgin polymers which generally have a high price and adversely affect the environment. Post-consumer polymer recycling is a substitute material solution from virgin polymers and is environmentally friendly so as to support the realization of a circular economy. Studies on 3D printing filaments from post-consumer polymers have been discussed in this article, especially for filaments derived from acrylonitrile butadiene styrene (ABS), polylactic acid (PLA), and polyethylene terephthalate (PET). In addition, this article also reviews the sources of recycled raw materials, difficulties during the process, mechanical properties, thermal properties and efforts to improve the quality of 3D printing products. The results show that recycling post-consumer polymers for 3D printing filament applications is a promising approach to reducing the environmental impact of 3D printing while still retaining the mechanical properties and printability of filaments. This article provides insight into several studies that address the development of 3D printing using post-consumer polymer materials.