Mechanical, Thermal, and Morphological Analysis of Himalayan Agave Fiber/GO Coated Fly Ash Hybrid Polypropylene Composites

Composites containing two different types of reinforcements offer a wide range of possibilities and synergistic properties. This study investigates the hybridization effect of chemically active fly ash (FA) (5 wt %) on the composites made from alkali (1 wt %) - APTES silane (2 wt %) treated Himalayan agave fibers (HAF) (25 wt %) and polypropylene (PP). Prior to FA activation, the planetary ball mill was used to suitably reduce the particle size of the FA with was confirmed by the dynamic light scattering approach. Secondary reinforcement FA was modified with APTES silane (1 wt %), followed by treatment with graphene oxide (GO) (0.5, 0.75, and 1 wt %). The highest tensile strength of 40.47 MPa and modulus of 1.49 GPa were observed for the hybrid composites fabricated from 0.75 and 1.0 wt % GO treated fly ash. Interestingly, this trend differed for flexural properties, and the highest flexural strength of 53.52 MPa was demonstrated by 0.5 wt % GO treated FA hybrid composite. Thermal characterization revealed that addition of fiber increased crystallinity but decreased thermal stability, whereas a good wettability of the fiber and FA in matrix was demonstrated through morphological characterization.