Low temperature oxygen plasma assisted surface modification of raw silk fibre and their characterizations

Abstract

Raw silk fibre was treated with low temperature oxygen plasma with an aim to improve its dyeability. The XRD study reveals that a fraction of the macromolecules on the surface and in the inner part of silk fibres are oxidized during plasma treatment. The overall crystallinity of the fibre surface is reduced and the short range order is increased. Plasma treated fibre showed gradual increase of peak intensity in the Raman spectrum, and the peak shifts to lower wave numbers. Change in the micro-structural properties was observed in the scanning electron microscope images but the mechanical property of silk fibre was found to be insignificant. Smooth and homogeneous coating of a natural dye extracted from the Indian mulberry (Morinda citrifolia) was observed in the case of plasma-etched silk fibre.