Effects of Fiber Size and Fiber Content on Mechanical and Physical Properties of Mengkuang Reinforced Thermoplastic Natural Rubber Composites

Abstract

Thermoplastic mengkuang composites are an alternative material to solve environmental pollution issues associated with synthetic polymers. Mengkuang, or Pandanus atrocarpus, raw fiber was cut, dried, ground, and sieved to the required size. The fiber was filled into the matrix of natural rubber (NR) and high-density polyethylene (HDPE) by melt blending via internal mixer. The blend of HDPE/NR at 60/40 ratio with fiber sizes of 125 µm, 250 µm, and 500 µm were prepared at fiber contents of 10%, 20%, and 30%. The effects of fiber size and fiber content on the thermoplastic composite were investigated using tensile test, impact test, water absorption, and field emission scanning electron microscopy (FESEM). The maximum tensile strength and tensile modulus were obtained at 20% fiber content of 250 µm fiber size. Impact strength gradually decreased with the increased percentage of fiber content at fiber size, 125 µm and 250 µm. The highest tensile strain at break and lowest water absorption was observed at 10% fiber content for all sizes being studied. The effects of fiber size on water absorption, and percentage of fiber content on impact strength and tensile strain at break were statistically significant (p < 0.05).