Comparative analysis of the mechanical and thermal properties of polyester and epoxy natural fibre-reinforced hybrid composites

In this work, a comparative analysis of the mechanical and thermal properties of polyester and epoxy single and hybrid natural fibre-reinforced composites was performed. Pure jute, jute + curaua and jute + sisal composites with two distinct thermoset polymer resins (an epoxy and a polyester) were produced. Tensile, flexural and impact tests were carried out, in accordance to ASTM standards, to investigate and compare the mechanical properties of the composites as a function of matrix and hybridization. In addition, a thermogravimetric analysis (TGA) was used to complete the comparative analysis of the thermal properties. Finally, a scanning electron microscopy (SEM) was used to examine the fracture surface of the tested specimens. It was found that the hybridization process improved the mechanical properties of the non-hybrid jute fibre based composites for both matrices used. The resin used as matrix plays an important role on the mechanical properties of the composites. The epoxy matrix based composites presented higher tensile strength, while the polyester based composites presented higher tensile and flexural stiffness as well as higher impact energy, when compared to the epoxy-based composite. TGA analysis showed that the thermal stability of epoxy-based composites was higher compared to the polyester-based composites.