The Effects of Oxidative Modification on the Surface Properties, Thermal Degradation Behavior and StructuralCharacterization of Coir Fibers

In this study, the effect of sodium perborate tetra hydrate that is a new alternative modification agent for coir fibers was investigated on chemical, structural, thermal and morphological properties of the fibers. The coir fibers were modified at different concentrations of sodium perborate tetra hydrate aqueous solutions. The effects of the modifications on surface chemistry, functional groups, thermal degradation behavior, crystalline structure and surface properties were investigated by fourier transform infrared spectroscopy, thermogravimetric analyses, x-ray difraction and scanning electron microscopy, respectively. According to the results, the modification processes decreased fiber surface hydrophilicity by increasing carbon/oxygen ratio and also decreased the intensities of the absorption peaks indicating hemicellulose and lignin. Cleaner fiber surface was achieved after the modifications. However, crystalline structure of the fiber was not affected significantly. The maximum degradation temperatures decreased with changes in lignin content of the fibers. The char yield values of the fibers increased after the modification which can possibly indicate enhancement in flame retardancy