Statistical Analysis in Homopolymeric Surfaces

Abstract

Surface topology investigation of luminescent polymeric films is a promising research area due to the interest in their technological application, mainly to large-area electroluminescent displays (Holzera et al., 1999). Surface topology of organic flexible materials is generally controlled by a chemical and physical process, the polymer coatings are generally heterogeneous, and the most significant changes occur in the nanometer scale (Gobato et al., 2002). The Atomic Force Microscopy (AFM) technique, in special, has made significant experimental contributions to three-dimensional imaging with high-resolution in a subnanometer scale, without specific sample preparation (Bar et al., 1998; Binnig et al., 1986; Gua et al., 2001). In soft biological or polymeric materials, the permanent contact of the tip produces irreversible deformation, modifying the surface topology (Magonov & Whangbo, 1996; Weisenhorn et al., 1992). To minimize these deformations, the AFM tapping mode was introduced as a non-destructive technique (Marti et al., 1999). In general, AFM systems include commercial software to control the probe and capture process, and analyze surface images such as height or phase. The subjective analysis of AFM images that sometimes depends on the high quality of the experimental data is commonly found in the literature. For example, quantitative analysis, uniformity, fractality, interface, nanostructure, composition, and others cannot be accomplished. The difficulty in performing the quantitative characterization of the surface increases during homopolymer films surfaces investigations, due to macro-molecule interpenetration, thus forming a very complex system (Marletta et al., 2010).