Advanced Materials Research Vol. 795

Abstract: In this study, copper-tungsten carbide composite was produced by mechanical alloying and powder metallurgy. The compaction pressures were varied from 100 to 600 MPa for observation on microstructure and properties of the composite. The result showed the microstructure was densified with the increased of compaction pressure. Within compaction pressure no fracturing was occurred. Increasing compaction pressure increased the density, hardness and electrical conductivity of the composite which related to the reduced of porosity area.

Abstract: This research is carried out to investigate the performance of concrete containing Polyethylene Terephthalate (PET) bottle waste as fiber. PET bottle waste was chosen because it is being thrown after single use and cause environmental problem. One way to recycle wasted PET bottles is grinded into irregular fiber. Then, it was incorporate with the concrete and test the performance of the concrete. The study was conducted using cylindrical mold of concrete to investigate the performance of the concrete in term of mechanical properties. A total of four batches of concrete were produced namely, normal concrete and concrete containing PET fiber of 0.5%, 1.0% and 1.5% fraction volume. In this research, the mechanical properties that were measured are compressive strength, splitting tensile strength and modulus of elasticity (MOE) following British Standard method. The results revealed that the presence of PET fiber in concrete will increase the concrete performance. Nevertheless, the content of PET fiber was specified in a specific limit to avoid effect of concrete strength.

Abstract: The volume of polymeric wastes like polyethylene terephthalate bottles (PET) is increasing at a fast rate. PET bottles annual consumption represents more than 300,000 million units. The majority of the PET waste is sent to landfill. Since PET waste is not biodegradable, it can remain in nature for hundreds of years. Previous investigations already confirmed the potential of PET waste in replacing aggregates in concrete and represents better option than send it to landfill. This paper reviews researches published on the performance of concrete containing PET wastes. In this researches PET waste will be incorporated with an established binder namely fly Ash. The increase of workability is caused by the small spherical shapes of the fly ash that reduces the friction between cement and aggregates. Then it will results in an increase in the workability and flow of fresh concrete. Overall, the decision of using recycled waste plastic as fiber in structure for the design of structures provides enough benefits that will make it worthwhile to be considered as an economical attractive option. Once the use of performance concrete using light fibre becomes more popular and the importance of research contribution in providing technical knowledge on this new material becomes apparent. Furthermore this paper will bring new name for the new combination waste material is called Performance of Waste Light PET Fibre Concrete (WLPFC).

Abstract: This paper describes the experimental investigation of relationship between splitting tensile strength and flexural strength with the compressive strength of concrete containing waste PET as fine aggregates replacement. Waste PET was reprocesses and used as the artificial fine aggregate at the replacement volume of 25%, 50% and 75%, Cylindrical and prism specimens were tested to obtain the compressive, splitting tensile and flexural strength at the age of 28 days. Based on the investigation, a relationship for the prediction of splitting tensile and flexural strength was derived from the compressive strength of concrete containing waste PET as fine agglegate replacement.

Abstract: The use of natural fibers at high percentages of loading in thermoplastic composites for the production of sustainable and green materials in consumer goods, furniture, automotive industry and construction industry is emerging. Several studies have been conducted by many researchers to improve the mechanical properties of the fibers and the fiber-matrix interface for better bonding and load transfer especially when high fiber loading is used. The natural fiber hydrophilic properties make the poor interface and poor resistance to moisture absorption when used to reinforce hydrophobic matrices. Therefore, this study investigates the effects of different surface treatment namely magnesium chloride (MgCl₂) and sodium hydroxide (NaOH) on the properties of kenaf fiber for different molarities. Morphology using scanning electron microscopy (SEM) and fourier transform infrared (FTIR) spectroscopy and tensile properties of kenaf fibers after different surface treatment are evaluated. Results showed that the treatment on kenaf fibers has removed the hydroxyl group in cellulose and increase the surface roughness which resulted in the improvement of the tensile properties of kenaf fibers as compared to untreated kenaf fibers.

Abstract: The effects of dynamic vulcanization on the thermal properties and swelling behaviour of vPE/rPE/EPDM blends were studied. The discarded polyethylene used in the study was obtained from local wire insulation industry. The thermal properties and swelling behaviour of the blends were analyzed. Results show that increasing of sulfur loading had improved the thermal stability of the blends. The swelling percentage and swelling index of vPE/rPE/EPDM blends also decreased, inversely proportional to the increasing of sulfur loading. Thus, the increased incorporation of sulfur loading had improved the chemical and oil resistance of the blends.

Abstract: The effects of carbon black (CB), silica and calcium carbonate (CaCO₃) in virgin polyethylene (vPE)/recycle polyethylene (rPE)/ethylene propylene diene terpolymer (EPDM) blends were investigated. rPE was melt blended with EPDM in different ratio by using a Haake Rheomix. The characterization such as swelling analysis and thermal properties were examined. Results indicated that, vPE/rPE/EPDM blend with CB show best oil (ASTM IRM 903) and toluene resistant and also thermal properties compared with silica and CaCO₃.

Abstract: The effects of SBR/NBRr blends on thermal properties of such thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) were carried out. Results showed that by incorporating the smallest size NBRr provided more surface area to interact with SBR polymers thus increased the level of crosslink. TG thermograms shown by incorporating the smallest size NBRr in all ratios exhibit better thermal stability compared to large size NBRr. Due to many crosslinks formed with the incorporation of S1, hence at the end stage of degradation there were more cyclic and aromatic carbon formed during the rearrangement of the existing char. SBR/NBRr R05 with small particle sizes S3 and S2 showed similar crystallization temperature (T_c) at 37.1 °C. However by using S1, there was a conversion of T_c to heat capacity transition from high to low energy level at temperature 37.3 °C. Smaller size of NBRr showed better dispersion with SBR matrix hence the chances of crosslink form between SBR and NBRr is higher compared to using large size of NBRr.

Abstract: The effects of different sizes of Batu Reput (Dolomite) filler which are smaller size (<63μm) and bigger size (75-150μm) on tensile and morphological properties of Batu Reput (Dolomite) filled SMR L and epoxidized natural rubber (ENR-50) blends were investigated. Results indicated that, the tensile properties, such as tensile strength (TS), elongation at break (E_b) and stress at 100% elongation (M100) of Batu Reput (Dolomite) filled SMR L higher than Batu Reput (Dolomite) filled ENR-50 blends, particularly, at 15 phr of smaller size of Batu Reput (Dolomite). The scanning electron microscopy studies proved, Batu Reput (Dolomite) filled SMR L illustrated a higher Batu Reput (Dolomite) - SMR L matrix interaction compared with Batu Reput (Dolomite) filled ENR-50.

Abstract: Photomasks are used as stencil to print images on semiconductor material. This study represents design and specifications of photomask for microfluidic fabrication. For a precise pattern transfer, the photomask should meet with certain considerations such as critical dimension uniformity, resolution and alignment. This paper explains the design of microfluidics with three channels using AutoCAD software for lab-on-chip application. Total surface area of the device is 242.52mm² in which the width and length is 12.00mm and 20.21mm respectively. The device was designed in particular size to meet its behavior as a disposable chip and increases the economic value when it is fabricated.