Synthesis of conducting polyaniline‐montmorillonite nanocomposites via inverse emulsion polymerization in supercritical carbon dioxide

Abstract

AbstractA new inverse emulsion polymerization and intercalation procedure in supercritical carbon dioxide (SCCO2) was initially employed to synthesize polyaniline‐montmorillonite (PANI‐MMT) nanocomposites. The effect of chemical groups in MMT galleries on intercalation in SCCO2 was investigated. The MMTs modified by different organic cationic surfactants were incorporated into the composite particles, and in unintercalated, partially delaminated or fully exfoliated state. The aminated MMT or fluorinated MMT were utilized to prepare conducting PANI‐MMT nanocomposites with highly concentrated (12–25 wt% loading to monomer), fully exfoliated MMT platelets in SCCO2. The structure and morphology of PANI‐MMT nanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), X‐ray powder diffraction pattern (XRD), and transmission electron microscope (TEM). Thermogravimetry analysis (TGA) was performed to demonstrate the enhancement of thermal stability of the composites. SCCO2 was shown to be more effective for impregnation, disaggregation and exfoliation of MMTs than isooctane, which indicates that SCCO2 is an alternative solvent for synthesis of some intercalated composite materials, not only based on the environmental friendly characteristic of SCCO2, but also owing to that SCCO2 can play an important role in intercalative polymerization. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers