Mechanical Properties of Bio-Composite Natural Rubber/High Density Polyethylene/Mengkuang Fiber (NRHDE/MK)

The use of mengkuang fiber (MK) as a filler in NR/HDPE/MK bio-composite was investigated. The suitability of MK as reinforcing filler was studied in terms of the mechanical properties and phase morphology formed. Melt-blending was performed using an internal mixer (Haake Rheomix 600). The processing parameters identified were 135 °C temperature, 45 rpm rotor speed and 12 min processing time. The optimum MK loading in 40/60 of NR/HDPE blend was obtained at 20 wt.% with the tensile strength, tensile modulus, and impact strength of 12.4 MPa, 377 MPa and 17.2 kJ/m², respectively. These results showed an enhancement in tensile strength of 10.7% compared to the unfilled NR/HDPE blend. The maximum impact strength obtained at 5% fiber loading was 23.5 kJ/m², which was 7.8% higher compared to unfilled NR/HDPE blend. The FESEM micrographs showed good adhesion between MK fiber and matrix. These mechanical properties enhancements proved the suitability of mengkuang fiber as potential reinforcing filler in NR/HDPE blend.