Optimization on Tensile Properties of Kenaf/Multi-walled CNT Hybrid Composites with Box-Behnken Design

Hybrid composites have recently become attractive to scholars due to their significant potential to overcome the drawbacks of monofiber composites. However, the simultaneous effects of independent parameters on the properties of these hybrid composites are still not clear as the previous studies have mostly focused on varying one parameter only. Therefore, a response surface methodology (RSM) is introduced. Accordingly, the present study attempts the modeling and optimization of four independent parameters on the kenaf / multi-walled carbon nanotubes (MWCNTs) hybrid composites by using three-level Box-Behnken RSM. The four parameters: kenaf fiber loading, NaOH concentration, MWCNTs loading and sonication time have been selected based on the past literature and their simultaneous effects on the tensile properties are studied. It was found that the optimized 10.029wt% of kenaf fiber loading, 4.057% NaOH concentration, 0.965wt% of MWCNTs loading and 2.970 h of sonication time predicted an optimum tensile strength and tensile modulus of 123.580 MPa and 16.084GPa respectively. Moreover, the validation through experiment of the predicted optimum results has been concluded and reveals that the results were reliable after considering the relatively low error levels. Besides, the response also displayed that the kenaf fiber loading had the highest degree of impact on the tensile properties compared to the other three parameters.