Untreated and treated with alkali (NaOH), acrylic acid (AA), diammonium phosphate (DAP), and maleic anhydride (MA) of coconut filter (CF) fibers were characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), and single fiber test. The composites were fabricated from CF and film resins (Polylactic-acid (PLA) and Polypropylene (PP)) using a hot press machine. Generally, our results indicated that chemical treatments improved the mechanical properties of CF fiber composites, except for the DAP-treated fiber/PP composite. The AA treatment of fiber produced the best adhesion at the fiber-matrix interface. Consequently, the tensile and flexural strengths of AA-treated fiber-reinforced polymer were the highest. CF fiber-reinforced PLA composites had better mechanical properties than CF fiber-reinforced PP composites. Our results show that CF fiber is feasible as a reinforcement for polymer composites.

Abstract. In present study, the effect of irradiation along with applied load and three periods on the ultraviolet (UV) aging of the polycarbonate polymer was investigated by observing the changes in the mechanical properties. Dog bone specimens of polycarbonate were subjected to different test conditions namely in the amount of applied load and the variation in exposure time to the UV lamp. The results showed that, with a constant applied load of 1kN, increase in the exposure time in UV radiation caused the mechanical properties to relatively increase at first and decrease gradually afterwards. However, for constant exposure time, the tensile strength showed much decrease with increase in applied load. For the test conducted at higher applied load of 3kN, the mechanical properties of material relatively improves in a drastic manner for the higher exposure time. It was inferred that the increase in applied load has a crucial role in the UV aging of polycarbonate for the given exposure time. Moreover, the morphology of the fracture area under different test conditions was observed by Scanning Electron Microscope (SEM).