Materials Science Forum Vol. 1007

Abstract: Socks fabrics seem a minor clothing in apparel categories but are indispensable item for daily activities for users. The function of socks is either for heat insulation of body temperature in cold weather or heat releasing to keep thermal neutral for foot in hot weather. Socks with good quality are conducive to prevent foot disease or smelly odor from foot. The wearing comfort of socks can be affected by the fabric properties of thermal transfer. The present study aims to investigate the relationship between the fabric parameters and thermal conductivity property of knitted socks fabric. The physical test on commercial socks fabric was carried out in standard condition atmosphere. It was found that the thermal conductivity of fabric was positively proportional to yarn count and thickness.

Abstract: Air permeability is one of the thermal comfort properties of clothing and fabrics. This study evaluated the air permeability properties of summer cooling towels of different brands available in the market, “Perfect Fitness”, “N-rit” and “Cooldyxm” and an anonymous ice towel. The air permeability function of the cooling towels was evaluated instrumentally. Other than the air permeability property, other fabric specification such as fiber composition, fabric type, fabric weight, fabric thickness, yarn linearity and fabric density were measured. Some specifications were found to have good statistical correlation with the air permeability. Based on the experimental results and statistical analysis, the sample of Perfect Fitness was found to have the poorest cooling effect, whereas N-rit, Cooldyxm and Ice Towel samples had comparable air permeability properties. The best performance of air permeability was seen in N-rit sample. The underlying reason could be ascribed to the fabric structure and thickness. This study can provide some information for choosing cooling towel for practical use.

Abstract: In this research, the nanostructured alginate (AL) membranes were prepared with natural bioactive compound, Cat's claw (Uncaria tomentosa) extract (UT). UT is broadly used as an anti-inflammatory agent and the effect on the treatment of Rheumatism was proved by many scientists. For this reason, we added this bioactive compound in the process of AL membrane formulation to improve the biological activities. 2-dimentional (2-D) and 3-dimentional (3-D) AL membranes were prepared with and without addition of UT extracts. 3-D AL membranes were prepared using ultrasound with high intensity. The wettability of AL membranes depending on the concentration of AL was studied by measuring contact angle and surface energy. Stabilization agent, poloxamer 407, was used to improve the stability of AL nanoemulsion. The effects of UT in 3-D AL membranes were studied by measuring swelling behavior and contact angle. The surface morphology was measured with scanning electron microscopy (SEM). Comparing to 2-D AL membranes, 3-D AL membranes presented rougher surface due to AL nanoparticles presence. When UT was incorporated in AL membranes, strong antioxidant activity and higher contact angle and swelling ratio were observed than non-UT incorporated AL membranes.

Abstract: This paper aims to research the high-temperature oxidation behavior of TiC/Mo composite. Adding 5 wt.% TiC, Mo-based composite was prepared by Spark Plasma Sintering. The composite was oxidized at different temperatures (400°C, 600°C, 800°C, 1000°C and 1200°C) and times (5 min, 10 min, 20 min, 30 min and 60 min). When oxidation was at 400-1000°C for 20 minutes, the degree of oxidation intensifies with the increase of temperature, and TiO2 was observed at 1000°C. While the temperature was 1200°C, the oxidation rate gradually decreased with the increase of time. The result shows that the formation of TiO2 can inhibit the oxidation process.

Abstract: Undoped ZnO and Ag-doped ZnO were prepared to use as near-infrared (NIR) shielding by simple precipitation method with zinc acetate and zinc nitrate as Zn precursor and silver nitrate as Ag precursor. The Ag-doped ZnO and undoped ZnO were characterized by XRD, SEM, and UV-vis-NIR spectrophotometer. The NIR reflectance performance reveals that Ag-doping improves the NIR shielding and optical property of pure ZnO. The 10 mol% Ag loading shows the lowest reflection in the visible region of about 15% and the highest reflection in the NIR region of about 50%. It not only shows the best NIR reflection but also exhibits the best thermal insulation. It reduces the inner temperature of the in-lab setup to mimic a house by 7.5°C when compared to the uncoated glass window. It is concluded that 10 mol% Ag-doped ZnO nanoparticles can result in UV-NIR shielding coatings.

Abstract: In this work, aluminum-doped ZnO (AZO) is synthesized for heat-shielding applications. A family of ethanolamine (EA: monoethanolamine (MEA), diethanolamine (DEA), and triethanolamine TEA)) is used to control the morphology of aluminum-doped ZnO (AZO) synthesized via a simple solvothermal method at the temperature of 120°C for 6 h. The samples were characterized by field-emission scanning electron microscopy (FE-SEM). The formation of primary ZnO nanoparticles (NPs) showed that TEA yielded highly packed-spherical aggregates not found when DEA and MEA were used. X-ray diffraction (XRD) found that all AZO samples have peaks of the ZnO hexagonal wurtzite structure. XRD patterns of aluminum were found for >10 mol%. UV-Vis-NIR spectrophotometer was used to study the optical property and heat-shielding of the near-infrared region (NIR, the wavelength from 700 - 2500 nm). All AZO NPs of 0, 2, 4, and 10 mol% exhibited strong NIR shielding ability up to 80% insulation. From these results, the AZO NPs have potential use as NIR shielding materials of low-cost and simple processes to be coated on an energy-efficient window as smart window coating in buildings and automotive thus reducing energy consumption, especially in air conditioning usage.

Abstract: This work focuses on the development of biodegradable active films packaging using natural compounds by reducing the plastic waste to environment but also as a potential substitute of synthetic preservative in food. Active film packaging was formulated using semi-refined carrageenan (SRC) biopolymer plasticized with glycerol (G), reinforced with different concentrations cellulose nanofiber (CNF) at 0 to 13% w/w incorporated 0.4% w/w α-tocopherol as natural antioxidants. Physical and mechanical properties of the film samples were analyzed. Active films reinforced CNF enhanced overall the tensile strength and the value of elongation at break significantly (p<0.05). Film samples reinforced with 10% w/w CNF improved the value of opacity, thickness, films solubility (%) and moisture content (%) with (5.60±0.14, 0.139 ±0.02, 27.89±2.41 and 18.88±1.06) respectively. In summary, an active film with 10% w/w CNF showed highest improvement on the mechanical and physical properties due to the uniform dispersion between CNF-SRC matrix interactions. Hence, the new formulation of active packaging film with showed competitive properties that could be an alternative solution for biodegradable films with function of food protection against oxidative degeneration.

Abstract: According to the observation of a metallurgical microscope, surface morphology of 2219 aluminium alloy under several corrosion circumstances, such as corrosion pits and grain boundary corrosion, is directly perceived. Furthermore, with a laser range finder, corrosion depth data can be measured, and by using some methods of data processing, the affection for this material of certain solution components and immersion time is studied quantitatively. This binary study mean not only provides both graphical and statistical analysis, but also gives the relationship between them, which makes the result more reliable.

Abstract: Building integrated photovoltaic (BIPV) is defined as the integration of photovoltaic (PV) modules into the building envelope (in this case the rooftile) to generate clean and environmental-friendly electricity from the sun radiation. The architectural integration of PV collector modules in new construction makes possible to create glazed surfaces which, besides being an aesthetical and functional innovation, generate electricity, that is allowing the realization of solar control and electric range with consequent energy savings. However, up until now, there have been limited studies that analysed BIPV from its materials point of views. This paper aims to expose rooftop BIPV materials that further might be used to replace conventional rooftiles such as terracotta or slate, concrete, plastic, and clay tiles. The flat rooftiles of monocrystalline-, polycrystalline-, and a-silicone based BIPV cells are being considered in this paper. Their benefits and drawbacks are also put into account. The parameters that were compared are materials, their physical layouts, and the transparency and output power.