XPS studies of chemically modified banana fibers

Banana fibers obtained from the sheath of the banana plant (Musa Sapientum) whose major constituent is cellulose were modified using various chemical agents in order to improve their compatibility with the polymer matrix. The change in the surface composition of the raw and chemically modified fiber was investigated using various techniques such as solvatochromism, electrokinetic measurements, and XPS. Surface characterization by XPS showed the presence of numerous elements on the surface of the fiber. Investigation of the surface after alkali treatment on the other hand showed the removal of most of the elements. Silane treatment was found to introduce a considerable amount of silicon on the surface of the fiber. The [O]/[C] ratio was found to decrease in all cases except for the fluorinated and vinyl silane treated fibers. Detailed investigation of the deconvoluted C 1s spectra revealed the change in the percentage atomic concentration of the various elements on the fiber surface. The dissolution of the various surface components by alkali treatment, which was earlier revealed by SEM, was further confirmed by XPS. The XPS results were found to perfectly agree with the solvatochromic and electrokinetic measurements.