Polyaniline fractals - a computer modelling

Computer simulations have been applied to study the fractal growth of polyaniline (PANI) microrods during the electrochemical polymerization. Formation of PANI microrods and their fractal structure can be explained as a kinetic effect well described within a modified diffusion-limited aggregation (DLA) model presented in this work. Microrods, if branched, form the angles of 60 degrees or 120 degrees and their fractal dimension d(f) is about 1.7, as predicted with DLA model based on a random motion of aggregating molecules. PANI nano-structure is also fractal in nature. The fractal dimension d(f) (about 1.9) and the form of fractals observed are comparable to those generated by a computer within our modified DLA model with a probability of aggregation dependent on the electrical conductivity and the structure of a macromolecule (aggregate) formed. (C) 2000 Elsevier Science S.A. All rights reserved.