SURFACE STRUCTURING OF SYNTHETIC-FIBERS BY UV LASER IRRADIATION - PART III - SURFACE FUNCTIONALITY CHANGES RESULTING FROM EXCIMER-LASER IRRADIATION

The chemical surface composition accompanying UV-laser induced surface structuring of fibrous materials such as poly(ethylene terephthalate) (PETP) is discussed. Only a few real chemical changes have been inves tigated up to now (formation of carboxylic groups on PETP, formation o f C=O bonds on polypropylene). Much more data exist on the formation o f yellow layers on the laser-treated samples, consisting of debris der ived from the ablation process. Analysis by laser desorption mass spec troscopy (LD-MS) and XPS confirm the composition of those layers as hi ghly carbonaceous. Methods for using LD-MS for fibre identification an d methods for avoiding debris-layer formation are described together w ith some surface grafting experiments. In some cases excimer irradiati on may be used to remove fabrication agents from polymer surfaces. (C) 1998 SCI.