The growing demand toward miniaturization and power device packaging required new die‐attach materials with high thermal conductivity (TC). Multitudinous attention is being paid to enhance the TC of thermally conductive polymer composites as it is easy to fabricate and environmentally friendly and has low‐cost processability. However, after years of extensive research, it can be concluded that reinforcing different morphologies of fillers (types, sizes, and shapes) into polymer composite creates interfacial thermal resistance (ITR) that greatly constrains the TC value. Thus, this article presents an exhaustive review in minimizing the ITR effect by optimizing the types, sizes, and shapes of the fillers used. This literature also seeks to review the use of different morphologies of fillers in single and hybrid polymer composites. It was found that hybridizing two different fillers shows remarkable TC enhancement due to its synergistic effect and formation of three‐dimensional network/conduction path. The size and shape of fillers used play a vital role in improving the TC of the polymer composite compared with the type of filler used due to more contact area created, which significantly reduces the ITR. The results presented here may facilitate improvement in the development of future work for new die attach of the thermally conductive polymer composite.

SUMMARY Acetic, propionic, butyric, isovaleric, n‐valeric, isocaproie, and n‐caproic acids were identified in hickory sawdust smoke by gas chromatography, and the relative amounts of each were determined. Formic acid could not be identified, because the flame ionization detector was not sensitive to this acid. A total of eight columns were evaluated, and three of these which gave best separation were used for identification by retention times as well as infrared spectrophotometry.

This paper presents an investigation of research objectives on the effect of tilt angle on microstructure and mechanical properties of dissimilar aluminum alloy sheets between AA5083 and AA6061, 5mm plates by using Friction Stir Welding (FSW) process in butt joint. The base materials of AA5083 and AA6061 were located on the retreating side (RS) and advancing side (AS), respectively. The welding process and the welding parameters such as tool pin profile, tool rotation speed, welding speed and tilt angle influenced the mechanical properties of the Friction Stir Welding joints significantly. For this experiment, the Friction Stir Welding materials joined under five different tilt angles (from 0oto 4o) with 86mm/min of welding speed and 910 rpm of tool rotation speed which were set similarly. Microscopic examination on the weld samples showed significant variation in the microstructure especially in the region of heat-affected zone (HAZ), weld nugget or dynamically recrystallized zone (DXZ) and in the base metal.

Stretchable conductive ink (SCI) had been extensively studied for fabricating stretchable electronic devices. In this study, silver conductive ink and thermoplastic polyurethane (TPU) were used as substrate. The ink was printed on the substrate using screen printing with different shaped patterns varied by the widths of 1 mm, 2 mm and 3 mm: (a) straight, (b) zigzag , (c) square and (d) sinusoidal. The measurement of resistance was performed using four-point measurement during unloaded and loaded conditions of the shape pattern. This study revealed that width had influenced the resistivity in all shape patterns, where the narrow the width, the higher the resistance is. Comparative studies of electromechanical analysis of the shaped patterns had showed that a 3 mm width of zigzag pattern had a better electromechanical performance by having stretchability to maximum of 7.78%. Straight and square shape patterns, however, exhibited the poor tolerate deformation as both failed to conduct electricity upon straining at the minimum elongation of 1.11%.

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Banana peel wastes of Musa Aluminata balbisiana (MBS) which known as a waste, and often ignored was collected and subjected to approximate composition study. The study revealed that the peel contained 78.58% of moisture content and 0.57% of volatile content. Oil extraction of MBS was performed using soxhlet method was yielded a pale brownish oil at room temperature with extraction recovery of 62.42%. The oil was exhibited a density, specific gravity, refractive index and viscosity of 08502 kg/m3, 0.8536 kg/m3, 1.47 and 3.29 cSt respectively. Physiochemical analysis shows that, the oil contained 2.64 of free fatty acids (FFAs), 0.77 g I2/100 g of oil Iodine values (IV), 7.46 mgKOH/g of saponification value (SV), 0.52 mgKOH/g of total acid number (TAN). Fatty acids analysis showed that, the oil composed of 46% of saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) and 4% of polyunsaturated fatty acids (PUFAs). The fatty acids analysis exhibit a desirable properties to further developed as a lubricants or as a lubricant additives due to ability to provides surface protective film in tribological behavioral due to the higher percentages of SFAs.

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