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S D Sathishkumar,
- Assistant Professor, Department of Mechanical Engineering, Sri Chandrasekharendra Saraswathi Viswa Maha Vidyalaya Deemed to be University, Enathur, Kanchipuram-631561, Tamil Nadu, India
Abstract
Natural fiber-reinforced polymer composites are increasingly investigated as lower-impact alternatives to conventional synthetic fiber systems. This work fabricated and mechanically characterized a sisal-coconut coir fiber-reinforced epoxy hybrid composite and compared its performance with a glass fiber-reinforced polymer (GFRP) epoxy composite under the reported laboratory conditions. The hybrid reinforcement contained 75% sisal fiber and 25% coconut coir fiber and was incorporated into an epoxy LY556/HY951 matrix by the hand lay-up technique. The laminate was cured at room temperature for approximately 24 h, cut to standard specimen dimensions, and tested in tension, flexure, and impact according to ASTM D3039, ASTM D790, and ASTM D6110, respectively. The sisal-coir hybrid composite exhibited an ultimate tensile strength of 186 MPa and a flexural strength of 313.78 MPa, compared with 94 MPa and 132.10 MPa, respectively, for the GFRP epoxy specimen. The average impact energy of the hybrid composite was 9.33 J, whereas the GFRP specimen absorbed 8.00 J. Under the specific fabrication and testing conditions reported, the hybrid composite therefore showed higher measured tensile, flexural, and impact performance than the GFRP comparator. The combined contribution of sisal to load bearing and coir to energy absorption provides a practical basis for further evaluation of this material in low- to medium-load-bearing applications. Additional replicate testing, statistical analysis, and durability characterization are required before broader structural substitution is established.
Keywords: Sisal fiber, coconut coir fiber, hybrid composite, epoxy resin, tensile strength
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Journal of Polymer & Composites
| Volume | 14 | |
| 05 | ||
| Received | 29/08/2026 | |
| Accepted | 15/09/2026 | |
| Published | 21/09/2026 | |
| Publication Time | 23 Days |