Surface Characterization of Low Temperature Plasma-Induced Cashmere Fibre by Air Gas

Low temperature plasma (LTP) processing technology was successfully applied to modify cashmere fibres and three kinds of assemblies were formed, i.e., weak-treated, optimised -treated and severe-treated ones. Treatment parameters were optimised in terms of the tensile behaviour, friction effect, wettability and touch feeling of cashmere without major modification of the properties inside the fibre. Detailed characterisation was performed to investigate the surface morphologies and chemical compositions of plasma-induced fibres. SEM demonstrates different minor etching effects of the treated cashmere fibres. XPS results indicate a significant increase in surface concentrations of O and N, and an obvious decrease in C after different LTP treatments as a whole. The C-H/C-C non-polar bonds were reduced and C-O/C-N, C = O polar groups were remarkably increased on the cashmere surface after plasma modification. In addition, a carboxyl group (O-C = O) formed. It is found that oxygen-containing bonds, namely, C-O/C-N, C = O and O-C = O, are responsible for the hydrophilic properties of cashmere.