Preparation of a polycation-intercalated layered manganese oxide nanocomposite by a delamination/reassembling process

A layered manganese oxide nanocomposite (PDDAMO) with poly(diallyldimethylammonium chloride), PDDA, incorporated between manganese oxide sheets, was synthesized by a delamination/reassembling process. The product was characterized by powder X-ray diffraction, elemental analysis, thermal analysis, FT-IR spectroscopy, and FE-SEM observation. XRD analysis showed that the expansion of the interlayer depended on the amount of PDDA intercalated; the largest expansion was 1.09 nm, corresponding to a bilayer of PDDA chains in the interlayer. Chemical analysis results showed that the PDDA intercalation progressed by an ion-exchange mechanism, and the PDDA polymer existed in a polycation form, not as a chloride salt. PDDAMO was comprised of platelike nanocomposite particles that were 1-5 mum in width. The thickness of each plate was 30 nm on average, which corresponds to the stacking of about 20 sheets of manganese oxide. The formation of the PDDAMO nanocomposite was hardly affected by the pH of the solution. PDDAMO had a high stability against extraction by acid treatment, probably due to the strong electrostatic attraction between manganese oxide sheets and PDDA chains.