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Fabrication of Acoustic Panel from Composites of Coconut Husk Waste Powder and Styrofoam Resin and its Sound Absorption Performance

In this study we have fabricated acoustic panel made from composites of coconut husk waste powder and styrofoam resin. The objectives of this study were to prepare the acoustic panel and to study the effect of amount of styrofoam resin and thickness of the panel on the sound absorption performance of the composites sample. The acoustic panel was prepared by varying the amount of styrofoam resin (i.e. 250 g and 300 g) mixed with 150 g of coconut hust waste powder and the thickness of the panel (i.e. 1 cm and 1.5 cm). The total of four samples were characterized for their sound absorption coefficient. The samples were tested at Physics Laboratory, Faculty of Mathematics and Natural Sciences, Sebelas Maret University, Solo. The sample testing results showed that the amount of styrofoam resin used in the making of the composites panel and the thickness of the panel have played important role in improving the sound absorption coefficient of the composites panel. Based on the sample testing results, among all the four acoustic panel samples, the sample with the best preformance in the noise absorption properties was the Sample B-2 with sound or noise absorption coefficient of 0.77698. Additionally, the sample with the lowest noice reflection coefficient value was the sample with styrofoam resin of 250 g and thickness of 1.5 cm (i.e. Sample A-2), which was about 0.39401 at frequency test of 1600 H.