Dynamic Mechanical Analysis of Pineapple Leaf/Glass Hybrid Fiber Reinforced Polyester Composites

The dynamic mechanical properties of randomly oriented intimately mixed hybrid composites based on pineapple leaf fibers (PALF) and glass fibers (GF) in unsaturated polyester (PER) matrix were investigated. The PALFs have high-specific strength and improve the mechanical properties of the PER matrix. In this study, the volume ratio of the two fibers was varied by incorporating small amounts of CF such as PALF/GF, 90/10, 80/20, 70/30, and 50/50, keeping the total fiber loading constant at 40 wt%. The dynamic modulus of the composites was found to increase on CF addition. The intimately mixed (IM) hybrid composites with PALF/GF, 80/20 (0.2 V(f) GF) showed highest E' values and least damping. Interestingly, the impact strength of the composites was minimum at this volume ratio. The composites with 0.46 V(f) GF or PALF/GF (50/50) showed maximum damping behavior and highest impact strength. The results were compared with hybrid composites of different layering patterns such as GPG (GF skin and PALF core) and PGP (PALF skin and GF core). IM and GPO hybrid composites are found more effective than PGP. The activation energy values for the relaxation processes in different composites were calculated. The overall results showed that hybridization with CF enhanced the performance properties. POLYM. COMPOS., 31:956-965, 2010. (C) 2009 Society of Plastics Engineers