Mechanical and thermal properties of kenaf fiber mat reinforced unsaturated polyester composites with the presence of graphene as nano filler

Kenaf fiber mat (KFM) reinforced unsaturated polyester (UPE) composites have been prepared using hand lay-up and compression moulding technique. In order to improve the mechanical and thermal properties of fiber, the KFM was treated with two different chemical treatments such as alkali and silane treatments with 3 hours of soaking time. To enhance the performance of KFM-UPE composites, graphene was also added as nano filler. Fourier transform infrared red (FTIR) analysis was used to investigate the changes of fibers chemical constituents before and after treated with alkali and silane treatment. Mechanical (tensile, flexural) and thermogravimetry analysis (TGA) characterizations were carried out to study and compare that properties of untreated, alkaline and silane treated KFM-UPE composites. Overall, the used of alkalized KFM-UPE composites showed the best mechanical and thermal properties. Therefore, alkaline treated KFM was selected to be re-prepared with graphene as nano filler in UPE composites at 0.5, 1.0 and 1.5wt.% filler loading. TGA was also used to study the thermal behavior of alkaline treated KFM-UPE composites with the presence of graphene. The mechanical and thermal studies showed that, the most optimum performance of KFM-UPE composites were obtained at 1.0wt.% of graphene. The morphological analysis of rupture surface of samples has demonstrated the improvement in fiber/matrix adhesion after chemical treatment and addition of graphene, respectively.