Preparation of poly(methyl methacrylate)/Na-MMT Nanocomposites viain-Situ polymerization with macroazoinitiator

Poly(methyl methacrylate)(PMMA)/sodium montmorillonite(Na-MMT) nanocomposites were prepared with a novel method utilizing a macroazoinitiator(MAI). To induce the intergallery polymerization of methyl methacrylate (MMA), the MAI containing a poly(ethylene glycol)(PEG) segment was intercalated between the lamellae of Na-MMT and swelled with water to enhance the diffusion of MMA into the gallery. The structure of the nanocomposite was examined using X-ray diffraction and transmission electron microscopy, and the thermal properties were examined using differential scanning calorimetry and thermogravimetry. The PMMA/Na-MMT nanocomposite prepared by intergallery polymerization showed a distinct enhancement of its thermal properties; an approximately 30 °C increase in its glass transition temperature and an 80∼100 °C increase in its thermal decomposition temperature for a 10% weight loss.