Investigation into the wet processing and surface analysis of Lyocell type fibres

• Main Author: Rosunee, Satyadev
• Published: University of Manchester 2002
• Subjects: 677
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.602950

The wet fibrillation behaviour of Tencel yams was investigated using a wet yam-onyam abrasion system. The effect of crosslinking using reactive dyes or colourless reagents was to improve the wet fibrillation performance by improving fibrillar cohesion. The effect of a range of typical wet treatments were evaluated and found to decrease the beneficial cross linking mechanism. Increasing the temperature of the testing bath increased the polymer flexibility giving rise to a decrease in wet abrasion. Nevertheless the wet abrasion of crosslinked derivatives was still better than that of the original Tencel. The role of swelling and dehydratingldeswelling agents on Tencel yams was examined and found to have significant effects. The wet abrasion system was combined with the surface analytical technique X-Ray Photoelectron Spectroscopy (XPS) to probe the nature of Tencel surface modifications and their possible effects on colour care and wet abrasion performance. Using elemental indicators such as N(ls) and S(2p) photoelectron peaks the presence of dyes and cationic fixing agents was demonstrated at the fibre surface. It was also demonstrated that the durability of a direct dye to washing was significantly improved by Matexil FC-ER. The nature of the 'cationic' Matexil FC-ER was characterised and the substantivity of the charged and uncharged components determined. Differences in the effect of cationic fixing agents on the wet abrasion of Tencel was established. The effect of perborate and non-perborate based detergent formulations on reactive and sulphur dyed Tencel was evaluated and differences in oxidative behaviour demonstrated. In particular, the increased oxidation of disulphide bonds in the sulphur dye was evident with perborate-based treatments. The role of specific surface (plasma treatments) and bulk modifications on the wet abrasion performance of Tencel were examined although few beneficial effects demonstrated.