Fractal growth patterns of polyaniline were developed during electropolymerization of aniline using the surfactants sodium dodecyl sulphate (NaDS) and NaDS containing cetyl trimethyl ammonium bromide (CTAB). Growth kinetics was studied and electric potential oscillations were monitored as a function of time. On addition of CTAB polymer growth was inhibited due to coordination of CTAB with the growing polyaniline chain. The average particle size of the polymer aggregate obtained from aniline- NaDS-H2O system was ~150 nm as evident by Transmission Electron Microscopy (TEM) results. Polymer aggregates were characterized by electrical conductivity measurements, X-ray diffraction (XRD) and Thermogravimetric (TG) studies. An interaction between NaDS and aniline was observed in the absence of electric field as evident by (i) electrical conductivity of aqueous solution of NaDS in the absence and presence of aniline, and (ii) their crystallization patterns on microslides. A mechanism for the development of fractal patterns and electrical potential oscillations is proposed on the basis of diffusion limited aggregation process.
Conformal dynamics of fractal growth patterns without randomness
