Thermomechanical Analysis and Structure of Sugar Palm Fiber-Reinforced and Woven Carbon Fiber-Reinforced Hybrid Epoxy Composites

The pursuit of sustainable yet high-performance materials has driven significant interest in hybrid composites combining natural and synthetic reinforcements. In this study, hybrid and non-hybrid epoxy composites of sugar palm fiber (SPF) and woven carbon fiber (WCF) were prepared with different layer configurations (D1–D9). The SPF fibers were subjected to an alkaline surface treatment to enhance adhesion to the polymer matrix. Thermomechanical analysis (TMA) demonstrated that the layer configuration critically affects the thermal expansion and dimensional stability of the composites. The most favorable TMA properties were obtained for the D1 configuration (SPF core and WCF outer layers), as evidenced by a low coefficient of thermal expansion (26 µm/m °C at 200 °C). FESEM analysis demonstrated improved interfacial adhesion and reduced void formation for the modified SPF. A balance between tensile strength, stiffness, and ductility was achieved for the hybrid laminates (D1 and D4), emphasizing the importance of interface engineering in improving damage resistance. SPF/WCF reinforced epoxy hybrid composites are promising materials for structural applications in the aerospace, automotive and construction industries where both thermal stability and environmental considerations are crucial.