Process Parameter Interaction Study for Epoxy/Kenaf Composites Preparation via Two-Level Full Factorial Approach

Abstract

2020 This study was conducted to understand the interaction involved between the process parameters of the solution mixing for the preparation of epoxy/kenaf composites via two-level full factorial approach. There are three (3) independent variables which are the kenaf fibre loadings (-5.00 wt.%; +35.00 wt.%), stirring period (-10.00 mins; +50.00 mins) and the stirring speed (-100 rpm ; +700 rpm ), involved in this work. A set of 2 3 full factorial design with three replications at a center point and no block was applied to yield a total of 11 set of experiments. The DesignExpert 6.0.8 statistical software has optimized the resulted tensile strength (TS) response as dependent variable of prepared epoxy/kenaf composites. It was found that the optimum processing parameter are at 100 rpm of stirring speed, 10 mins of the stirring period and about 5.00 wt.% of the kenaf fiber loading, with the highest coeficient of determination R 2 value of 99.9%. Fracture surface morphological observation via SEM has been performed to correlate further the interaction between the processing variables toward an optimum resulted TS response. In overall, this study has significance to facilitate manual processing of natural fiber based epoxy composite started at the early integration between the kenaf fiber as reinforcement phase and epoxy as the matrix phase, using a high speed mechanical stirrer Observation of Epoxy/Kenaf Composites For tensile fractured surface morphological observation, the scanning electron microscope (SEM), model Zeiss Evo50 was utilized. The observation using SEM was performed at 5.00 kV of an accelerating voltage. The fractured surface of selected epoxy/kenaf composite was cut and mounted on an aluminium stub with carbon tape prior of palladium-gold coating to eliminate the electrostatic charging effects. From the SEM observation, the fracture surfaces morphological feature of fibre-matrix interface and fracture mode were evaluated further.