In this work, a novelty solid propellant based on Isophorone Diisocyanate (IPDI) with Hydroxyl Terminated Natural Rubber (HTNR) binder network was successfully developed. The preparation of Liquid Natural Rubber (LNR) by chemical degradation Deprotenized Natural Rubber (DPNR) using cobaltous was carried out. From the FTIR spectroscopy, a broad hydroxyl group peak at 3444cm-1 was obtained from HTNR. Rubber network depict a strong carbonyl group C=O at 1714cm-1 and amine group N-H at 3433cm-1. NMR analysis also proves that there was hydroxyl group presence in the sample where broad peak at range 1-3 ppm and 3.5 ppm peak for -HOCH2CH2CH2-. Four different mol ratio of HTNR with IPDI was carried out to find the best formulation with good properties as propellant. Flory-Rehner equation depict that only slightly increasing occur with higher IPDI mol ratio but mixing with Ammonium Perchlorate (AP) and Aluminium Powder (AL) significantly improve the crosslink density. Melting point for HTNR is near to room temperature and it increase abruptly after crosslink with IPDI up to range of 148-150 °C. For all formulation, cross section morphology showed occurrence of porosity and brittle type of failure however HTNR has good contact with AL and AP. 2 : 1 molar ratio depict the best burning rate but the combustion characteristic shows less energy and spark compared to HTPB binder.
Xylitol-based polyesters such as poly(xylitol sebacate) PXS are said to be the potential new materials for tissue engineering due to their adjustable mechanical and degradation properties. However, the result indicates that the elastomers are very soft and have a low elongation at break. Therefore, to increase the mechanical strength and minimize the rate of degradation, glutamic acid was added as the third monomer into the PXS. Novel Poly (xylitol Sebacate Glutamate) (PXSG) was successfully synthesized through melt polycondensation without using any harsh solvents and catalysts. The mixture was synthesized at 120°C for about 8 hours. Post polymerization process was carried out in the oven at 100 °C for three days to develop the crosslink network formation. Several testing and characterization were conducted to evaluate the effect of glutamic acid concentration in the polymer. From the result, FTIR spectroscopy confirmed the ester bond formation, tensile strength and Young's modulus increased significantly while the percent of elongation at break and degradation rate decreased as the glutamic acid ratio increased.
Abstract. The development of polyurethane with hydroxyl access in a molecule leads to a new alternative of low toxicity green product. Palm oil is one of the major commodities in Malaysia. The potential of palm oil to be used as coatings raw material such as alkyd is limited due to low unsaturated side on fatty acid chains. To overcome this limitation, palm oil was modified through transesterification process to produce polyol. Acrylated isocyanate (urethane oligomer) was then grafted onto polyol to produce polyurethane with vinylic ends. The polyurethane was formulated with different cross-linkers (reactive diluents) and cured under UV radiation. The effect of three different diluents; monoacrylate, diacrylate and triacrylate on the properties of cured polymer were studied in this research. Fourier Transform Infrared (FTIR), Hydroxyl Value Titration, Gel Content, and Volatile Organic Compound (VOC) were used for characterization. Physical testing performed were Pencil Hardness and Pull-Off Adhesion test. Novel palm oil-based polyurethane coatings have been found to have good properties with mono acrylate functionality.
The epoxy primer coatings with various size of treated glass fiber was successfully developed using hand brushing technique on carbon steel plate. The glass fibers used were treated with silane coupling agent, 3-aminopropyl triethoxysilane. The Fourier Transform-Infared Spectroscopy (FTIR) affirmed the presence of silanol group at 1221.12cm-1 .Hence, the primer coating was prepared with three different sizes of treated glass fiber (45, 150, and 250 μm) and the corrosive properties has been studied. The corrosion rate was determined using Tafel plot and the immersion test was done in 3.5% NaCl and sea water for 9 days. Formulation of epoxy resin-GF-45μm displayed the optimum size to reduce the corrosion rate of epoxy primer coatings at 8.3713 mm/year and polarization resistance was the highest at 107.48Ω which indicates that epoxy coating have higher resistance towards corrosion, coating adherence and there was formation of more protective film on steel.Whilst immersion in 3.5% NaCl solution and sea water followed the same trend with 45 μm exhibited the less corrosive behavior for 9 days exposure. When the solution penetrated into the coating, the ultra-short glass fibers prevent the water from permeating and prolong the water diffusion path. Thus, it provided good anti-corrosive properties for formulation 2 at 45μm GF. In conclusion, the size of GF plays an important role in determining the corrosive behavior of epoxy primer coatings. The optimum size of GF at 45 μm proved to diminish the corrosiveness of carbon steel plate.
Mineral carbonation is a process where carbon dioxide (CO2) is converted into solid carbonates. The product of mineral carbonation is obtained when CO2 is being contacted with alkaline earth metals, such as calcium and magnesium. In this research, the team focusing on producing precipitated calcium carbonate (PCC), as a solution to manage CO2 release which comes from high CO2 content natural gas field production. To make this process economically feasible, the team has researched obtaining valuable PCC quality which is marketable in various industries. The quality mainly measured in terms of particle size, where the particle size will determine the application of the PCC. This study investigates the effect of feed solution retention in reactor towards PCC particle size, using continuous mineral carbonation system. In this system, Milk of Lime, which is Calcium Hydroxide (Ca(OH)2) solution used as feed. To produce this solution, 7 g/L Calcium Oxide (CaO) is suspended in deionized water and stirred. This solution is injected in the range of 0.8 L/min to 1.2 L/min into pressurized CO2 in the range of 10 bar to 80 bar. The retention time is varied by using mechanically modified reactor inlet cap, where the feed inlet time is delayed by elongation of feed injector inside the reactor by 15 cm (NEWCAP). Particle size of the product was analyzed by using Malvern Mastersizer 3000. Experimental data show that by shortening the feed solution retention time inside the reactor, will produce smaller particle size. Using the unmodified reactor inlet, the obtained product particle size ranging (D50) from 15 micron to 25 micron. On the other hand, using NEWCAP reactor inlet the obtained particle size ranging (D50) from 8 micron to 20 micron.
Gamification learning is proven to be an educational approach to nurture student’s interest to learn by using the game invented and designed with their special elements in learning environments. This project applies a systematic design approach using inventive principles to develop mathematics learning tools for primary school students. A product that gives real experiential learning to the students with versatile and innovative values developed using inventive principles, ensuring that kids have the experience of learning by doing, this product helps to develop new skills, new attitudes and new ways of thinking. Four different inventive principles which are self-service, feedback, color change and dynamization are used to produce the final product which is simpler, faster and cheaper. Since there is a significant growth of the economic world, the revolutionary is sure to occur. The scenario indicates that the possibility of ineffective teaching method and tradi-tional method of teaching are no longer suitable for this generation of kids. It attracts kids to learn mathematics using gamification as a plat-form. The project uses a color sensor that replaces the numbers. The color sensor then sends the information to the microcontroller. The final working prototypes named MEGO acronym for Mathematics Education Go.
Precipitated calcium carbonate (PCC) is synthetic calcium carbonate that has high purity of more than 98 wt% of CaCO3 content. Owing to its unique characteristic whereby its shape and size can be controlled to tailor to various applications, PCC has seen great demands in many industries such as paper, paint, plastic, food, ceramics, cosmetics, pharmaceutical, and many others. PCC can be synthesized via various methods and the most often used method in industry is via carbonation process. This process has caught interest of the oil and gas industry for utilizing existing carbon dioxide waste from plant processes. Precipitation of PCC is carried out using hydrated lime under various conditions at different gas purity (1 mol% CH4 + 99 mol% CO2 , 40 mol% CH4 + 60 mol% CO2 ), different gas flowrate, and different stirring rate. All experiments are carried out using 1 litre of ionic solution at ambient conditions. All samples are characterized using Field Emission Scanning Electron Microscopy (FESEM), Particle Size Distribution, X-Ray Diffraction (XRD), and X-Ray Fluorescence (XRF). FESEM analysis shows different surface morphology for different methane content with calcite formation. The particle size for all PCC produced at different parameters are comparable at the range 5-9 microns depending on the mixing rate used whereas XRF results indicate very high purity of CaCO3 of more than 99 wt%.
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