Nano-Scale Surface Embrittlement of Textile Fibers

Kevlar fibers through the microscopeThe research is focused on detailed characterization of oxidation layer of both treated and untreated textile fibers (polypropylene, Nylon and Kevlar) during autoxidation and exposed environmental conditions. Currently there exist no studies available in the literature to understand the features such as actual thickness of the oxidation layer, its mechanical properties (from the surface to the center of the fiber), surface morphology, susceptibility to surface cracks and finally effect of these surface cracks on overall performance of proposed fibers. The textile fibers undergo wear in addition to fatigue loading conditions during their service. Surface embrittlement due to oxidation can generate surface cracks and promotes wear as well as pre-mature failure in course of fatigue service loads. Hence it is essential to understand above issues in order to reduce surface cracks and subsequent wear of textile fibers and to improve their performance. The outcomes of the funded project are the following: (a) detailed understanding of extent of autoxidation of commercial fibers (as received) by nano-characterization and surface morphological studies (b) Influence of autoxidation on further ultraviolet (UV) and thermal degradation conditions, and (c) recommendation of surface coatings or treatments to counteract the further degradation mechanisms under UV and thermal degradation conditions. The above nano-characterization studies will be conducted using atomic force microscopy (AFM) by carefully designing specimen preparations. The knowledge base resulting from this study will improve durability of textile fibers and eventually enhance competitiveness of the U. S. Textile Industry.