The Study of Thickness Ratio and Bamboo Fiber and Recycled-Polypropylene Core Layer on Acoustic and Mechanical Properties of Sandwich Composites

Abstract

The construction materials mostly focus on overall mechanical properties. One of pollutions often found is the noise pollution. For this reason, the sandwich structure is the source of solution for this kind of problem. This structure can add various insulation for different properties into the sandwich composites. This study focuses on the material of the core layer and the thickness ratio between the face sheet and the core layers of the sandwich structure. Therefore, the objective of this research is to study the behaviors of the core material and the thickness ratio between face sheet layer and core layer that influence both an acoustic and mechanical properties. The raw materials for the core layer include bamboo fiber and recycled polypropylene (rPP) with three different thickness ratios for the face sheet and the core layers namely 2-6-2, 3-4-3, and 4-2-4 mm. The results revealed that the sandwich structure, compared to the wood plastic composites (WPCs), had a significant influence on the increase of noise reduction coefficient and hardness values whereas the flexural strength and compressive strength decreased significantly. Additionally,  increasing thickness ratio from 4-2-4 to 2-6-2 mm had an influence on the increase of noise reduction coefficient and flexural and hardness values whereas the compressive value decreased significantly. Furthermore, the bamboo fiber as a core layer significantly provided higher noise reduction value than that of rPP. On the other hand, the rPP gave significantly higher overall mechanical properties than that of bamboo fibers as a core layer.