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The rapid progress in electronic applications for movable devices requires the conductive matrix to be not only flexible but also stretchable. A simple microstrip patch antenna was fabricated based on silver ink polysiloxane composite with a stretchable polysiloxane substrate at a resonance frequency of 2.50 GHz. It is designed at a postpercolation threshold of 35, 45, and 60 vol % conductive filler loading so as to allow a consistent conductivity at an ample range of cyclic stretching. With the presence of coupling agent and additives, the patch antenna displayed an extremely good adhesion between the ink and the substrate, which prevents any local rupture during stretching. Variable range hopping model verified that conductivity occurs through hopping and tunneling mechanisms, giving transient optimum conductivity in the range of 10–70 S/cm at 10–20% strain amplitude range. The fabricated prototype of microstrip patch antenna displayed a decreasing resonant frequency with strain. Of note, the radiation loss S11and the bandwidth values are proportionally related to the conductivities during stretching. These results verified the proposed mechanisms of construction and destruction of conductivity occurring during the percolation threshold process. The fabricated antenna proved the feasibility for use as a stretchable device at an ultrahigh-frequency band.

Greywater is a wastewater originating from shower, bathtub, bathroom sink, kitchen sink and laundry. Despite the fact of wastewater in Malaysia may also include a complex mixture of organic matter, suspended solids, bacteria and common household chemicals, when used wisely and in a manner that is protective to public health and the environment, it can helps preserve limited water supply. This study aims the efficiency of adsorption of organic pollutants in greywater by using natural fibers such as Kenaf dust and Chitosan powder to treat the colour of water and the cause of odours from the greywater. The objective of this research is to identify the characteristics of greywater according to standard effluent discharge, as well as to characterize the physical properties of Kenaf (Hibiscus Cannabinus L.) and to determine the percent removal parameters of greywater by using Kenaf dust and Chitosan powder as organic removal. Raw greywater samples were taken at main drain Kompleks Parit Raja. The results for raw greywater samples obtained such as COD (253 mg/l), TSS (1800 mg/l), pH (5.89) and turbidity (47.5 NTU) were compared to Effluent Standard Discharge (EQA 1974). The COD removal efficiencies by using kenaf dust and chitosan powder amounted to 51% and 50 %, also TSS removal 89% and 100%. The pH and turbidity amounted to 6.76 and 7.04, 46 NTU and 4.46 NTU respectively. The overall removal of organic pollutants increased with different mass of adsorbents, then the optimum adsorbents were selected 30%, 40% and 50% to form as beads.

A relatively new way to improve processibility thermoplastics is via the use of crosslinkable monomers which can act as reactive plasticizers and reduce the viscosity in the early stage of processing. The monomers can polymerize and phase separate during final stage of processing thus recovering the original thermoplastics properties. In this work, the applicability of epoxy as reactive plasticizer for polyetherimide (PEI) was investigated. The properties of PEI/epoxy blends without and with curative were studied in order to determine the effect of the monomer on the processibility of the PEI and the thermo-mechanical properties of cured blends. Differential Scanning Calorimetry on blends without curative indicated single glass transition temperature (Tg) at high PEI content suggesting miscibility of the system and plasticization of PEI in the presence of epoxy while cured blends indicated two Tg due to phase separation. Scanning electron microscopy of the cured blends indicated two phase morphology with PEI dispersed particles size increased in continuous epoxy matrix with increasing PEI (up to 30wt% PEI). In blends with 40wt% PEI and more, phase inverted morphology was observed where increasing PEI content caused reduction of epoxy particle size in continuous PEI matrix.

Recently, many researchers focus on the nanoscale fillers to enhance electrical properties of composite due to the uniqueness of material. In this study, polyimide/barium titanate (BaTiO3) nanofibers films were prepared by incorporating electrospun BaTiO3 nanofibers with polyimide derived from 2,2-Bis [4-(4-aminophenoxy) phenyl] propane (BAPP) and 3,3',4,4'-Biphenyl tetracarboxylic dianhydride (BPDA). The obtained nanofibers were modified with (3-Glycidyloxypropyl) trimethoxysilane as coupling agent before integrating into the polyimide matrix. Microstructure and dielectric properties of BaTiO3 nanocomposites were investigated. The results showed BaTiO3 nanofibers were successfully produced at nanoscale regime and well dispersed in the hybrid film after modification and ultrasonication method. Dielectric constant of the nanofibers films were improved and increased with increasing of BaTiO3 nanofibers concentration while dielectric loss remains relative low.

Nowadays, flexible electronic is an important technology to produce flexible electronic devices due to it offers the attractive features such as possibility of product types and designs, with reducing size and weight, and low cost. Poly (3,4-ethelenedioxythiophene):poly (stylenesulfonate) (PEDOT:PSS) is a conductive polymer which possess high conductivity, high electrochemical, and low redox potential. PEDOT:PSS and PEDOT:PSS/Graphene (GP)/Dimethyl sulfoxide (DMSO) conductive ink ware deposited on Polyethylene terephthalate (PET) flexible substrate using desktop inkjet printer. Conductivity and thickness of conductive pattern at 1, 3, 5, 10, 20 layers were investigated in this study. It is observed that sheet resistivity of the conductive pattern is influenced by number of printed layers. Addition of GP at 20 layers of PEDOT:PSS/GP/DMSO conductive pattern exhibits the lowest sheet resistivity at 44 ohm/󠇯󠇯sq compared to PEDOT:PSS conductive pattern of 1.81×104 ohm/󠇯󠇯sq.

The loadings effect of carbon black and silanized-silica filled 75/25 phr/phr of natural rubber/recycled chloroprene rubber (NR/rCR) blends were compared with the unfilled NR/rCR blends. Different filler loading between in the range of 10- 40 phr was used. The rubber blends were prepared by using a laboratory two-roll mill and rheometric characteristics were studied using the Monsanto moving die rheometer (MDR 2000) at 150 °C. The addition of CB and silanized-silica showed different trend in scorch and cure time but showed similar trend in torques. The incorporation of both fillers caused higher tensile strength than that unfilled rubber blends. By comparison, the silanized-silica filled NR/rCR blends showed higher tensile strength than CB filled NR/rCR blends. Morphological characterization as observed from SEM justified these results.

Coagulation and flocculation are essential processes in a number of diverse disciplines, including biochemistry, cheese manufacturing, rubber manufacturing, and in water and waste water treatment. Coagulation-flocculation is effective for removing high concentration organic pollutants and heavy metals in water and wastewater. However, limited information exists on the efficiency of this coagulation-flocculation process for biodiesel wastewater treatment. The biodiesel wastewater is basic (alkaline), with a high content of oil and grease, and a low content of nitrogen and phosphorus. As such, biological treatment of the biodiesel wastewater is expected to be very difficult. For this reason supportive physic-chemical methods are often used. Although one of the most frequently employed method is coagulation. Therefore, this study was conducted to investigate the efficiency of coagulation and flocculation processes for removing suspended solid (SS), color, COD and oil and grease from biodiesel wastewater. Aluminum sulfate, polyaluminum chloride, ferric chloride and ferric sulfate as a coagulant in biodiesel wastewater treatment were studied using a standard jar test apparatus. The result shows that, at the optimum dose of PAC (300mg/L), the percentage removal of SS, color, COD and oil and grease respectively 97%, 95%, 75% and 97% compared to only 92%, 92%, 53% and 99% at the optimal dose alum (500mg/L), 95%, 93%, 63% and 97% at the optimum dose of ferric chloride (350mg/L) and 88%, 88%, 54% and 94% at the optimum dose of ferric sulfate (450mg/L). The effect of coagulant dosages on suspended solid (SS), color, COD and oil and grease removal showed similar trend and PAC was found to be superior was observed at reasonable lower amount of coagulant i.e. 300mg/L. The results showed that coagulation-flocculation is effective as a pre-treatment for treating biodiesel wastewater.

The fabrication of porous poly (ethylene glycol) (PEG)-based hydrogel scaffolds via epoxy-amine crosslinked polymerization was conducted in this research works. PEG was chosen as the main component of the hydrogel scaffolds due to their unique characteristic including high hydrophilicity, biocompatibility and low toxicity properties. The effects of different solvents ((water, dimethylsulfoxide (DMSO), triethylene glycol dimethyl ether (TGDME), etc) toward physical and mechanical properties of fabricated PEG-based hydrogel scaffolds were investigated to identify the suitable solvent for fabrication of porous hydrogel scaffolds. From the results obtained, DMSO was selected as the solvent because the produced hydrogels scaffolds possessed the optimum physical properties as compared to other solvents. In tissue engineering field, porosity of scaffolds play key role for cell attachment, grow and proliferation consequently help in regeneration of new tissues. Therefore, in this study the macroporous hydrogel scaffolds were produced via introduction of fused salt templates in the range sizes of 100–300 μm (small) and 300–600 μm (large) in the fabrication process. Improved interconnectivity of pores was achieved and pores sizes obtained were according to the size of salt particles utilized in the template. Modification of the scaffolds pore morphology resulted in a reduction in the mechanical properties as we expected.

Epoxidised silsesquioxane (EPSQ) polymer was prepared by hydrosilylation process involving epoxy-disiloxane (EDS) and vinyl silsesquioxane (VSQ). They were characterised and analysed using Fourier Transformed Infrared (FTIR) and H-and Si-Nuclear Magnetic Resonance (NMR) spectroscopy. Pattern development was successfully performed affording well defined features of micron scale using suitable solvent developer. It was demonstrated that the feature definition was highly dependent on time of solvent dissolution and stirring rate. Optimization of several parameters such as resist thickness, pre-bake and post-bake time, ultra-violet (UV) intensity and exposure time are still required for the improved performance photo-resist material. However the results proved that the EPS can be potentially used as photoresist in photolithography application.

We has synthesized hyperbranched polyamides (HPI) series containing s-triazine rings derived from melamine in the main chain, according to A3 + B2 approach which involving the emulsion polymerization reactions of melamine in hydrochloric acid and stepwise thermal imidization. The effect of curing temperature on the degree of imidization (DI) films of Melamine-BPADA (4,4'-(4,4'-Isopropylidenediphenoxy) bis (phthalic anhydride) has been examined by using the techniques of FTIR (Fourier transform infrared) and SEM-EDX (Scanning Electron Microscope-Electron Diffaction X-Ray). The DI varied significantly with annealing temperature before the films were fully cured. The Melamine-BPADA film was nearly fully cured when annealed at 180 °C, while the same was revealed for SEM-EDX. The morphology of the Melamine-BPADA film did not vary with annealing at temperatures and the FTIR experiment fairly match those from the SEM-EDX.

A series of high refractive index of α,ω-vinyl silyl terminated polydimethylsiloxane-co-polydiphenylsiloxane was synthesized by the equilibration ring opening – anionic polymerization of cyclic organo-siloxane oligomers in the present of 1,3-divinyltetramethyldisiloxane as terminating agent. Structural modifications were characterized by use of FTIR, H-NMR, and solution viscosity. UV-visible spectroscopy was analyzed which reveal a good transmittance in the region 400 – 750 nm radiation for all polysiloxanes.The presence of diphenylsiloxane unit results in a linear increase of the refractive index of the resin. These features favor good application as encapsulant for high brightness LED (HBLED) packaging.

A series of carbazole substituted poly(dimethylsiloxane) (PDMS) was synthesized by hydrosilylation reaction of 9-vinyl carbazole into PDMS structure. It was then crosslinked with vinyl trimethoxysilane by condensation reaction. The fabricated product increased in refractive index with increasing carbazole content. The higher carbazole content also produced high thermal stability with an increase in Tg and degradation temperature. This behaviour owe much to the carbazole moiety as well as the formation of crosslink network These features contribute to potential use as electronic devices encapsulants and coatings.

Poly (vinyl alcohol) (PVAL) was a common stabilizing agent used in formulate polymeric drug encapsulated micro-/nanoparticles. In preparing poly (lactic acid) (PLA) micro-/nanoparticles by emulsion and solvent evaporation (ESE) technique, the particle size and distribution have shown dependent on PVAL concentration. The focused of this project was to investigate the PVAL function in relation to significant changes in particle size. These studies were relatively important, as it was the basic studies of material usage in ESE fabricating process. The function of PVAL as, either surfactant that able to reduce interfacial tension or stabilizer to provide steric stability was further investigated by measuring the interfacial tension (IFT) of two liquids and zeta potential of the particles. As PVAL concentration increased, the reduction of IFT was only pronounced at the early stage of PVAL incorporation from 16.02 m N/m (absence of PVAL) to 2.0 m N/m (presence of 1 % PVAL), while zeta potential of particles was gradually decreased from-25 mV to-10.2 mV. As conclusion, the presence of PVAL could reduce the interfacial tension. However, to further stabilize the particle (e.g. reduce size and narrow size distribution) in the fabrication process, the steric stabilization provided by PVAL give more significant advantages.

In this work, a type of hydrogel from waste linear low density polyethylene (LLDPE), acrylic acid (AA), and starch was prepared using N, N-methylenebisacrylamide (MBA) as the crosslinker, and benzoyl peroxide as the initiator. The hydrogel was characterized by Fourier transform infrared spectroscope (FTIR), scanning electron micrograph (SEM), and X-ray diffraction (XRD). The results confirmed the incorporation of acrylic acid and starch in the LLDPE chain. SEM results show that the prepared hydrogel has a porous structure. Product showed maximum water absorbency of 180 g/g in distilled water.

Surface hydrophobicity of poly (lactic acid) have raise the concerns of surface incompatibility of PLA to function as biomaterial. Thus, various approaches have been made to improve the surface hydrophilicity of PLA. In the present paper, PLA materials were surface modified by alkaline hydrolysis. The indication of the reduction in water contact angle value, from 65 ̊ to 50 ̊ and 15 ̊, in 0.01M and 1M alkaline concentration respectively, proven surface hydrophilicity of PLA film was improved. Further alkaline treatment after 24 hours shows not significant reduction in contact angle. Whereas, the erosion of film surfaces treated under 1M alkaline solution have been observed under polarized optical microscopy. Intrinsic viscosity measurement was also conducted to monitor the surface treatment process. As a whole, surface treatment was successful and sufficient when no further decreased in contact angle value, thus prevent extensive surface erosion.

Huge amount of waste electrical and electronic equipments (WEEE) or electronic waste (E-waste) has been produced every year in the world. It consists of valuable and hazardous metals that can be reused or extracted to minimize the environmental impact. This study is focusing on the investigation of recycling potential of e-waste through manual dismantling process and leaching test. The leaching test was conducted by changing the initial pH with constant stirring speed, constant water-sample ratio and in open air. The morphological structures of the solid samples were observed by SEM and the liquid residue was analyzed by Atomic Absorption Spectroscopy (AAS). It was found that total time required to dismantle all parts in the waste motor is about 10 minutes and the part that required longest dismantling time was armature windings. The metal elements that were observed are Fe, Mg, Pb and Cr. It was found that the pH of the solution increased with the increasing leaching time. The dissolution of Fe and Pb was high in the early stage of leaching but gradually decreased afterward. The dissolution for Mg and Cr was low throughout the leaching process. It was revealed that the metal elements in e-waste can be dissolved using this method and further investigation to increase the dissolution rate is required to ensure that the method proposed is applicable in industry. However, dissolved concentration of Pb must be controlled to ensure that it follows the permissible amount set under environmental standard.

Conventional methods to obtain foot anthropometry for custom made sports shoes using anthropometer, callipers and measuring tapes are inaccurate due to the complex anatomy and curvature of the instep, foot arc and related joints. They lead to poor repeatability and large variances, particularly when measurements are taken of different people. Measurements from 3D model have been claimed as a perfect tool to obtain anthropometric data. However a commercial 3D foot scanner to create a 3D foot model can be very costly. In this paper we propose a low cost 3D foot scanner system by integrating available image capture technology such as the Kinect®, appropriate 3D scanning software and a foot scanner rig. An experiment was conducted to compare the anthropometry data taken using conventional method and from the 3D model. The differences recorded for all regions were found to be less than 5%, suggesting that the 3D model produced by this method is accurate. The use of 3D scanner has also decreased the measurement duration, thus increasing the repeatability whilst decreasing human errors that normally occur during the measurement process.

A series of carbazole substituted poly (dimethylsiloxane) (PDMS) was synthesized by hydrosilylation reaction of 9-vinyl carbazole into PDMS structure. It was then cross-linked with vinyl trimethoxysilane by condensation reaction. The fabricated product display increasing in refractive index with increasing carbazole content. The higher carbazole content also produce high thermal stability which is suitable for electronic device encapsulation applications. The modification also increase Tg of the polymers displayed by differential scanning calorimetry analysis. This behavior owe much to the carbazole moeity when it was successfully incorporated into PDMS chain.

This work reports a simple chemical reduction route for the preparation of uniformed Ag nanoparticles whereby a fine control over the sizes of the Ag nanoparticles was studied by varying the concentrations of the reducing agents used. In characterization, UV-Vis spectroscopy showed the changes in optical properties of the Ag nanoparticles with regards to their sizes, where as the XRD patterns of the synthesized Ag nanoparticles confirmed the distinct peaks approximately at 2θ = 38.1°, 44.3°, 64.4°, 77.4°, and 81.5 representing Bragg’s reflections from (111), (200), (220), (311), and (222) planes of the face centred cubic lattice phase. This route of synthesis is feasible to produce Ag nanoparticles with diameters in the range of 30-45 nm.

Synthesis of porous silica via styrene natural rubber sacrificial template is investigated. This research is divided into three steps which are synthesis of Styrene Natural Rubber (SNR), SNR/silica film formation and formation of porous silica. The synthesis of SNR is obtained via emulsion polymerization which involves styrene as monomer and Deproteinized Natural Rubber (DPNR) latex as based materials. SNR is used as sacrificial template to produce porous silica. The amount of silica loading and mixing method were varied during formation of SNR/silica film. Calcination is use to completely remove styrene and latex, leaving behind a new material with porous structure. It was found that the increasing of silica loading will enhanced the porosity of the structure and the best mixing method can be obtained using shaker instead of mechanical stirrer and magnetic stirrer. The porous structure can be observed via Scanning Electron Microscopy (SEM).

Crystal structure of an aromatic polysulfones containing biphenylene units was elucidated using diffraction simulation technique extracted from X-ray data and interfaced with computational modeling. The chain conformations and configurations were derived from a synthesized oligomer and several analogous structure of past studies. It was found that the polymer adopt an orthorhombic Cmcm with the adjacent aromatic rings attached to the sulfone linkage orthogonal to each other whilst the biphenylene unit are coplanar. The chain conformation and crystal systems are consistent with the analogous polymer containing wholly uniphenylene unit.

In this research, natural rubber (NR) with halloysite nanotubes(HNTs)/carbon black (CB) hybrid filler at various filler loading was investigated where the total filler loading used in each compound were 40 phr. The curing characteristics, fatigue life and morphological properties of HNTs/CB/NR nanocomposites were studied. Laboratory two-roll mill was used for mixing process. The results revealed that vulcanizates containing more HNTs in hybrid filler exhibit longer scorch time (ts2) and cure time (t90) for curing characteristics and higher in fatigue life compared to vulcanizates with 40 phr of CB. The images from scanning electron microscope (SEM) confirmed that replacement of carbon black with halloysite nanotubes improved the fatigue life by showing more tearing surface on vulcanizates.

A cross-sectional study was conducted to identify the factors related to smoking habits of adolescents among secondary school boys in Kelantan state, Malaysia. A total of 451 upper secondary male students from day, boarding and vocational schools were investigated using a structured questionnaire. Cluster sampling was applied to achieve the required sample size. The significant findings included: 1) the highest prevalence of smoking was found among schoolboys from the vocational school; 2) mean duration of smoking was 2.5 years; 3) there were significant associations between smoking status and parents' smoking history, academic performance, perception of the health hazards of smoking, and type of school attended. Peer influence was the major reason students gave for taking up the habit. Religion was most often indicated by non-smokers as their reason for not smoking. Approximately 3/5 of the smokers had considered quitting and 45% of them had tried at least once to stop smoking. Mass media was indicated as the best information source for the students to acquire knowledge about negative aspects of the smoking habit. The authors believe an epidemic of tobacco use is imminent if drastic action is not taken, and recommend that anti-smoking campaigns with an emphasis on the religious aspect should start as early as in primary school. Intervention programs to encourage behavior modification of adolescents are also recommended.

Pleomorphic adenoma involving the soft palate is uncommon. Patients with this condition can present with a mass in the oral cavity, dysphagia, and difficulty breathing. Resection of the soft palate may have a functionally detrimental effect on these patients, resulting in rhinolalia and nasal regurgitation. A patient in whom reconstruction of the soft palate defect using a uvulopalatal flap provided a simple and effective method of myomucosal tissue replacement is presented. There were no postoperative flap-related complications, rhinolalia, or regurgitation.

Presents information on Jerudong anticline which provides an outcrop example of multiple phases of diapir growth and interaction with country rock. Geological map of the Jalan Jerudong area; Structural evolution of the Jerudong fault zone; Implications for hydrocarbon geology.

A series of hydrosilyl-terminated polydimethyl-siloxane (HTP) of different molecular weight was cross-linked with 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetra siloxane (D4V) to afford a three dimension cross-link network. They were systematically synthesised through acid-catalyzed ring opening polymerization of octamethyl-cyclotetrasiloxane (D4) followed by hydrosilylation reaction using Platinum complex catalyst. Chemical structure of HTP was characterized using FTIR and H-NMR. Mechanical properties were established using Shore A hardness which were closely related to the cross-link density.