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Current conventional cool boxes which use expanded polystyrene (EPS) as its insulating material cannot seem to maintain storage at low temperature for long periods. This study aims to determine the effect for different types of insulating materials which can be used in cool boxes to improve its thermal insulation. Using theoretical and simulation approach, three out of six potential insulating materials were chosen in terms of their heat transfer rate, and temperature at the outer wall. The three best insulating materials, polyurethane (PU), expanded polystyrene (EPS) and poly-glass fibre (PGF) were then tested at three different room temperatures experimentally using the thermal insulation test to determine the best insulating material for a cool box. Tensile and density were also conducted to identify the mechanical behaviour and properties of these insulating materials. From the results obtained from the experiment, polyurethane (PU) recorded the longest time taken for ice to change into water at the three different temperatures when compared to other insulating materials. The results showed that when thermal conductivity is low, the heat transferred through the walls of the cool box was also low thus resulting in better thermal insulation of the cool box. This study gives a better understanding in term of thermal insulation and the results obtained from this study can help with the production of better cool boxes with improved thermal insulation.

Copper is well known as a valuable material, particularly for electrical industries due to its excellent properties. Besides, the price for copper scrap is also higher in comparison with other metal scrap materials found in many electrical appliances such as computer equipment, electric motor, transformer, and other components. This paper describes the potential of recycled copper wire shaped into a form suitable for heat sink application. The samples of wire mesh for this research were fabricated by compacting copper wire with different weight. Compaction was done to form a cylindrical shape with a diameter and height of approximately 25 mm and 30 mm, respectively. These samples were evaluated for porosity, thermal conductivity, and permeability. The experimental results showed that the sample with the lowest porosity exhibited great promising conductivity. In addition, lowering the amount of copper wire in compaction resulted in low density, thus improved its lightweight properties. The greater amount of porosity resulted in greater permeability. The optimum properties with a combination of the excellent thermal conductivity and permeability are necessary for heat sink application to ensure that the parts work effectively.