Suzi Salwah Jikan

Rheological Behaviour of Polypropylene Through Extrusion and Capillary Rheometry

For the past decade, polypropylene (PP) has become one of the most widely use polyolefin especially for intensive activities in research, product development and commercialization. The factor is strongly contributed by the high demands and usage predominantly in food packaging, automotive industries, fabrication of electric and electronic components and currently its utilization in building structural component for civil needs. Despite their variety in terms of its applications, PP has to be brought into melted stage first before it can be transformed into desired shapes. PP possesses relatively high melting point, low density, high tensile modulus and it is relatively low-priced compared to other thermoplastics. In addition, commercial PP consists of generally linear molecular structure thus it can provide low melt strength and exhibits no strain hardening behaviour in the melted stage. This suggests that PP is suitable for injection moulding, blow moulding and extrusion processing techniques (Rahima et al., 2011).

Melt Flow and Mechanical Properties of Polypropylene/Recycled Plaster of Paris

Polypropylene (PP) composites have better material properties such as good strength, better stiffness, improve of ductility; good stability and thermal expansion; and low cost of production. Nevertheless, these properties depend on the matrix phase, the phase dispersion of fillers and strengthening mechanism, shapes and arrangements of filler particles and the bonding interface between filler and matrix [1]. Plaster of paris (POP) has been chosen as filler in this composite system because it is used in many ceramic manufacturing and construction sectors which produce lots of POP wastes. It becomes one of the environmental issues due to the amount of used POP that has been disposed without recycling. Therefore, it is crucial to develop new composite material which consists of recycled POP as filler in order to assist the government in addressing the environmental issue.

Delamination of Kaolinite by Intercalation of Urea Using Milling

The effect of milling on structure of kaolinite-urea intercalates were studied. Untreated and treated kaolinite samples were examined by Field scanning electron microscopy (FESEM), X-ray powder diffraction (XRPD) and Fourier transform infrared (FT-IR) spectroscopy. The basal spacing of kaolinite measured by X-ray powder diffraction (XRPD) increased from 1.02 to 3.62 nm after intercalation by urea. Significantly, nature of intercalation was reached through formation of hydrogen bonds between urea and both Si-O and AlOH groups of the interlayer surface of kaolinite.

Physical Properties of Edible Films Based on Tapioca Starch as Affected by the Glycerol Concentration

The aim of this work is to study the influence of different proportions of glycerol on the properties of tapioca starch films. The films were characterized to determine crystallinity by using X-ray diffraction (XRD), thermal property by differential scanning calorimetry (DSC) and mechanical property by tensile test. The DSC thermograms show a decrease in the melting temperature (TPeak) with increase in the glycerol content. According to XRD diffractograms, pure starch exhibits crystallinity, but gelatinisation converts the starch film with 0 (w/w) % glycerol to amorphous, it gains back its crystallinity with the increase in the glycerol concentration. Mechanical properties were also influenced by variation of the percentage ratio of glycerol. The tensile strength was observed to decrease with increase in glycerol concentration whereas the elongation at break sharply increase with increase in glycerol concentration.

Production of Cu-Sn-Zn Ternary Alloy Coating via Electroplating

This research deals with the interest in production of Cu-Sn-Zn ternary alloy coating via electroplating on carbon substrate by using less hazardous electrolyte. A detailed study was made on the effect of different concentration of reducing and complexing agents. The surface morphology and phase structure of the deposited layers were examined by scanning electron microscope (SEM) equipped with energy dispersive x-ray spectroscopy (EDS), respectively. The results confirmed that the layers of Cu-Sn-Zn was obtained with this less hazardous electrolyte.

Effect of Glycerol on the Properties of Tapioca Starch Film

Biodegradable films from tapioca starch (TPS) were formed by tape casting. The impact of glycerol (0, 5, 10, 15 and 20%) on the mechanical properties was investigated. The increase in glycerol content reduces the tensile strength while increasing the elongation at break. The varying concentrations of glycerol led to changes in tapioca starch edible film properties, potentially affecting film performances. The merging and increase in the intensity of absorption between 3700-3300 cm-1 as a result of increase in glycerol proportion is due to possible interaction of the OH groups in TPS and glycerol thereby increasing intermolecular H-bond.

Synthesis of Polymethylvinylsiloxane from Several Silicon Compounds Followed by FTIR and NMR Techniques

Polymethylvinylsiloxane (PMVS) were prepared by pre-hydrolysis/condensation of several silicon compounds: methylvinydichlorosilane (MVDCS) and dimethyldichlorosilane (DMDCS) followed by catalysis equilibrium copolymerization by dibutyltin dilaurate (DBTDL). All manipulations in the experiments were performed under ambient condition. The PMVS were characterized by Fourier transform infrared spectroscopy (FTIR). This method has provided information about the structure of the polymer. The 13C NMR techniques give two sets of carbons at 1.77 ppm and 136.0 ppm consist of signals from carbons of both ligand groups, whereas 29Si NMR signals of the-22.49 ppm and-35.98 ppm region are due to silicon sites bearing the methyl and vinyl ligand groups; the 29Si signals of the - 109 ppm region are due to silicon sites without ligand groups attached.Keywords: Polymethylvinylsiloxane, copolymerization, NMR

Effects of Different Carbon Sources for High Level Lactic Acid Production by Lactobacillus casei

The fermentation process utilization to produce lactic acid has been studied from carbohydrate source and another source because of several significant reasons. Above all the production of biotechnology construction is found to be less costly compared to chemical synthesis. The production of biodegradable lactic polymer from lactic acid utilization of raw material can easily be obtained from industrial wastes such as pineapple waste. The process can positively affect the environment by reducing the environmental problems. The aim of this study is to estimate the effects of glucose concentration of pineapple wastewater as the carbon source on the volume of Lactobacillus casei (L. casei) subspecies in producing lactic acid. Five different glucose concentrations as carbon source are used for production of high lactic acid in the fermentation process using L. casei. L.casei could be ingesting the glucose presented within the levels tested and converts all into lactic acid. The result shows efficient yields of 0.09 g lactic acid/g glucose. The highest level of lactic acid is at 125.71 g/l and was obtained from 100 % pineapple waste medium. When the carbon source is at 4 g/l, the level of lactic acid is decreased to 84.22 g/l. The fermentation time increases with the increment of sugars. It is more than double if the medium is composed of 100 % of pineapple waste. Therefore pineapple waste is the best alternative as carbon source for bacteria growth because it is more cost effective.

Effect of Mica Content on the Physical, Mechanical and Morphological Properties of Alumina-Cullet-Mica Ceramic

This research is conducted in order to determine the best composition of alumina-cullet ceramic with the addition of mica powder. The alumina-cullet-mica composites (ACMCs) were produced by using powder compaction method. All raw materials used such as alumina, cullet and mica for fabricating the samples were first mixed, compacted and finally the samples have to undergo the sintering process. It is observed from the physical, mechanical and morphological analyses that the properties of ACMCs are highly dependable on the mica content.

Multilayer of Ni/Cu Coating Produced via Electroplating Process

Nickel (Ni)/ Copper (Cu) multilayer were deposited on Cu substrate by electroplating process using dual bath technique. Individual sample of multilayer with sublayer thicknesses of 1 μm, 5 μm, 10 μm and 50 μm have been produced. The structure of the multilayer was characterized by X-Ray Diffraction and Scanning Electron Microscopy whereas one of the mechanical properties of the samples was investigated by means of Vickers Hardness. The results showed that the surface hardness of the coated Cu substrate increases if compared to that of pure Cu substrate. Additionally, these values increased when sublayer thickness of samples were decreased.