Preparation and Characterization of Polyaniline / Montmorillonite Composite by Situ Emulsion Polymerization

Polyaniline(PANI)/montmorillonite(MMT)composites were prepared by situ emulsion polymerization of aniline at 0 °C in the presence of MMT in aqueous solution with ammonium persulfate (APS) and dodecylbenzene sulfonic acid (DBSA) as oxidant and surfactant (acid dopant), respectively. Infrared spectra revealed the shift of N-B-N stretching vibration band, suggesting the presence of interfacial interactions between PANI chains and clay layers. X-ray diffraction showed an increase in the interlayer spacing from 1.26 nm for MMT to 1.468nm for PANI/MMT10%, signifying PANI was intercalated into the MMT galleries and the expansion is in agreement with the intercalation of single chains with extended chain conformation. Thermal gravimetric analysis suggested that the introduction of MMT clay resulted in improvement of thermal stability of the composites. It was found that when the MMT content reached a certain limit (30%), the PANI/MMT showed higher conductivity than pristine PANI .