One of the main concerns of wood industry is the supply of wooden raw material. So it is important to consider the issues that address part of the existing concerns in different ways, such as reducing wood consumption in the production of wooden products. Application of lightweight composite products using polystyrene is considered as a solution to reduce the consumption of raw materials. Important properties considered for these types of products include their behaviors against electricity and acoustic properties. This study aims to evaluate the dielectric and acoustic behaviors of the composite studied herein.
In order to construct test samples, the most optimum treatment was selected from the treatments based on mechanical strength and physical properties to examine the electrical behavior and acoustic properties. To prepare lightweight test samples polystyrene, control samples were made at a densities of 0.7 g/cm3 (C1) and 0.5 g/cm3 (C2). The first density of control sample was chosen to compare the test specimen with a standard composite, and the second density of control sample was selected to compare the test sample with a composite product of similar density without polystyrene granules.
The results of electrical resistance test showed no significant differences between the lightweight test sample and C2 with a density of 0.5 g/cm3 due to their density equivalence. Also, electrical resistance was not significantly different between specimens with a density of 0.5 g/cm3 and heavier specimens with a density of 0.7 g/cm3. The results indicated that the specific gravity of the samples indirectly affected the electric resistance of the samples. At a certain density, the addition of polystyrene granules resulted in improved electrical resistance and acoustic properties of the samples.
The results of the tests showed that decreasing density of the samples resulted in increased electrical resistance and improved sound absorption of the samples. The presence of polystyrene granules in test samples, in addition to acting as a strong insulator, has an effect on the behavior of the samples possibly leading to an increase in their electrical resistance. Polystyrene granules have directly affected the acoustic properties of the samples. The results showed that lightweight boards using granular polystyrene can be used effectively in cases where there is a need for increased electrical resistance and improved sound insulation property, taking into account the allowable mechanical load tolerance by the boards.