Surface and Interface Analysis of Fibers Sputtered with Titanium Dioxide

Abstract

Nanoscale titanium dioxide (TiO2) films were deposited on the surface of polyester (PET), polypropylene (PP), and viscose fibers by using direct current (DC) reactive magnetron sputtering. The effect of different fibers on the surface structure and morphology of TiO2 thin films was investigated by atomic force microscopy (AFM). The cohesion and adhesion of the brittle titanium dioxide coating on the soft manmade fiber substrates was analyzed by scanning electron microscopy (SEM). The SEM images of coating interfaces were captured after TiO2 coated fibers were cut in a self-made simple apparatus. For comparison, the SEM images of the coating interfaces were captured after the coated fibers were broken in a single fiber strength tester. The results indicate that the characteristics of TiO2 deposited films were related to the structure and the morphology of the thin films which were determined by surface energy and roughness of different manmade fibers. Relatively smooth and high energy surface ultimately yielded uniformly deposited film and better adsorption to TiO2 clusters. The mechanical strength of the deposited film and the cohesion to the fiber substrate may be reduced for high surface roughness, because of the build-up of more micron cracks in the sputtering process.