Thermal and viscoelastic properties of a bilayer woven kenaf fabric/oil palm EFB mat epoxy hybrid composites

Natural fiber composites represent a class of materials and products that can enhance sustainability in the field of composite science. This paper aimed to assess and characterize natural fiber hybrid composites of woven kenaf and oil palm EFB-reinforced epoxy resin in terms of thermal and viscoelastic properties, which were prepared by using the hand lay-up method. Five sample designs include single composites of woven kenaf (K) and oil palm EFB, as well as hybrid composites with ratios of 30EFB:70K, 50EFB:50K, and 70EFB:30K. By using a dynamic mechanical analyzer (DMA) and a thermogravimetric analyzer (TGA), dynamic three-point bending characteristics were examined in aspects of the viscoelastic properties; the storage (E′) and loss modulus (E″), damping factor (Tan δ), derivative thermogravimetric (DTG) and thermal stability, respectively. The result found that the hybridization of woven kenaf/oil palm EFB enhanced the thermal stability and dynamic properties of the hybrid composites. In terms of dynamic mechanical analysis, hybrid composite 50EFB50K showed better properties compared to others. In addition, the hybrid composite of 70EFB30K has demonstrated significantly better thermal stability, char residue, and decomposition temperature, indicating relatively stronger heat stability. It can be concluded that hybrid composites 50EFB50K have a brighter prospect to be used in both structural and non-structural applications requiring rigidity, and thermal stability since it has better overall properties compared to other hybrid composites.