The fractal structures in highly sulfonated polyaniline

Using transmission electron microscope (TEM), the fractal structures have been found both in the colloid aggregates and in the colloidal particles of highly sulfonated polyaniline. In the present paper, the concept and mathematics model of fractal have been introduced into conjugated polymer. The colloid aggregates appear as an open dendriform structure with fractal dimension 1.43 and its growing process can be simulated by the Diffusion Limited Cluster Aggregate (DLCA) model. The simulated pattern by computer and the theoretic fractal dimension are consistent with the experimental results. Since the colloidal particle is generated in the evenness field formed by the dispersion media, the screening effect has been weakened and the colloidal particle is a spherical structure with fractal dimension 1.86, which is denser than colloid aggregates. The Random Rain (RR) model can be applied here and the simulation pattern and fractal dimension are coincident with the experiment results. So the system can be accounted as multi-fractals structure.