Polycarbonate/Montmorillonite Nanocomposites Prepared by Microwave‐Aided Solid State Polymerization

Abstract

AbstractSummary: Polycarbonate/montmorillonite (MMT) nanocomposites were prepared by microwave solid‐state polymerization. The MMTs were modified with alkyl ammonium salt. Pre‐intercalated polycarbonate nanocomposite was prepared using two conventional methods; a melt process and a solution process. Melt processing was accomplished in a Haake internal mixer for 30 mins at 180 °C. Solution processing was accomplished in a homogenizer using chloroform. The wide‐angle X‐ray diffraction (WAXD) peak indicating the gallery size of MMTs was shifted to lower levels after the pre‐intercalation process. Subsequently, microwave solid‐state polymerization converted the pre‐intercalated nanocomposite into the exfoliated nanocomposite. WAXD revealed that exfoliation and/or further intercalated structures were obtained when comparing the results from the microwave solid‐state polymerization with results from conventional solid‐state polymerization using oil heating. This means that microwave solid‐state polymerization is more effective than conventional solid‐state polymerization using oil heating. It was shown that conventional melt and solution processing of MMT and polycarbonate prepolymer yielded intercalated nanocomposites with interlayer spacing of 2.5 and 2.7 nm respectively. Microwave solid‐state polymerized nanocomposite showed the exfoliated and/or intercalated structure, whereas conventional solid‐state polymerization using oil heating only increased the gallery size of MMT. The thermal decomposition behavior and morphologies were investigated by thermogravimetric analysis (TGA) and transmission electron microscopy (TEM).Schematic diagram of microwave solid‐state polymerization.magnified imageSchematic diagram of microwave solid‐state polymerization.