A comparative study of the microemulsion and interfacial polymerization for polyindole

Polyindole was successfully prepared by the microemulsion polymerization and interfacial polymerization using ammonium persulfate (NH4)2S2O8 as an oxidant. Cetyltrimethylammonium bromide (CTAB) was employed as a surfactant in the microemulsion system. Polyindole was characterized via Fourier-transform infrared spectra (FTIR) and UV–vis absorption spectra. The hollow microsphere morphologies of polyindole obtained by the microemulsion polymerization were confirmed by scanning electron microscopic (SEM) and transmission electron microscopic (TEM) images. The sizes of the hollow spheres were in the range of 1 μm to 3 μm. However, polyindole synthesized by the interfacial polymerization was composed of many nanoparticles. Furthermore, cyclic voltammetric (CV) study was done to investigate the electrochemical behaviors of polyindole.