The focus of this research is to synthesis different nanocomposites by in situ chemical polymerization. The nanocomposites were prepared by intercalating monomers such as aniline, iodoaniline or combination of aniline and 2-iodoaniline into modified montmorillonite clay. The syntheses were carried out using ammonium persulfate as oxidant with different molar ratios of oxidant to monomer. The resulting nanocomposites were investigated and confirmed by X-ray fluorescence spectroscopy, XRD, UV-visible, FTIR spectroscopy, cyclic voltammetry and transmission electron microscopy techniques. XRD patterns show that, the intensity of diffraction peaks for polymers/(M-Na) composites are lower than that for (M-Cu). This is attributed to the interaction of montmorillonite with polyaniline (PANI), polyiodoaniline (PIANI) and poly (ANI- co-2-IANI) molecular chains. The FTIR and UV-vis spectroscopic results also confirmed the presence of iodine in the nanocomposite. When looking at the yield of the process, highest yield is obtained for the poly (ANI- co-IANI) (80:20 molar ratio) and the lowest yield is for PANI/M-Na composite.