Mechanical Properties of the Coir Fiber-reinforced Polypropylene Composites: Effect of the Incorporation of Jute Fiber

Coir yarn-reinforced polypropylene (PP)-based unidirectional composites were prepared by compression molding. Coir yarn content in the composite was optimized and 20% yarn content showed higher mechanical properties. Jute yarns (20%-100%) were incorporated into the coir-based composites. It was found that 20% coir and 80% jute-reinforced PP matrix composites performed the best results. All the materials (coir, jute, and PP) were irradiated with gamma radiation from 400 to 1000 krad. PP-based composites (20% coir and 80% jute) showed the highest mechanical properties at 600 krad of total gamma dose. Starch (2-10% in aqueous solution) was used as stiffening agent for the yarns and it was found better unidirectional position of the yarns inside composite over the untreated composite. It was reported that composites prepared with 5% starch treated yarns (coir and jute) for 5 min soaking time demonstrated the best results. Scanning electron microscopy, thermal degradation, water uptake, and electrical properties were also studied.