Influence of chemical modification of kenaf fiber on xGNP-PP nano-biocomposites

Abstract

Very recently emerging trends in polymer nanotechnology has revealed tremendous upsurge in application of graphene and derivatives in development of multifunctional nanocomposites. In present work, recycled polypropylene filled with increasing concentration of kenaf flour modified with sodium hydroxide/cetyl-trimethylammonium bromide (C-TAB) and filled with 3-phr graphene nanoplatelets (xGNP) hybrid nanocomposites were compatibilized using maleic anhydride grafted polypropylene and prepared via melt-intercalation using co-rotating twin-screw extruder subsequented by injection molding. The mechanical and morphological properties of NaOH-C-TAB modified materials (T-KRPPG) were studied and compared with untreated (U-KRPPG) samples. Transmission electron microscopy, field emission scanning electron microscope, Fourier transform infra-red spectroscopy (FTIR) and X-ray diffraction (XRD) analysis were applied in characterizing the microstructure and morphology of the materials. Mechanical tests revealed that tensile strength of T-KRPPG nanocomposites were superior in comparison with untreated (U-KRPPG) samples. In addition, the flexural strength, flexural modulus, and Young’s modulus of C-TAB treated kenaf xGNP (T-KRPPG) nanocomposites were superior in comparison with the untreated (U-KRPPG) samples. The morphological images of the tensile fractured surface of modified T-KRPPG nanocomposites revealed reduction of microholes and fibres aggregation signifying enhanced xGNP-fiber-matrix inter-facial adhesion due to kenaf flour modification with NaOH/C-TAB. XRD analysis revealed exfoliation and homogeneous separation of xGNP in matrix. FTIR analysis revealed no variations in peak positions of xGNP to suggest any significant chemical interactions between xGNP and other componenets.