Novel polyacrylonitrile/Na-MMT/silica nanocomposite: Co-incorporation of two different form nano materials into polymer matrix

Polyacrylonitrile (PAN)/Na-montmorillonite (Na-MMT)/SiO2 nanocomposites were synthesized via in-situ emulsion polymerization. The X-ray diffraction (XRD) measurements and transmission electron microscopy (TEM) observations show that the Na-MMT layers were exfoliated in polymerization and the nano materials are well dispersed in the polymer matrix. The thermogravimetric analysis (TGA) suggests that co-incorporating Na-MMT and SiO2 into the polymer matrix significantly enhances the thermal stability of the polymer. At same nano material loading, the PAN/Na-MMT/SiO2 nanocomposites show superior thermal stability with respect to the PAN/Na-MMT and PAN/SiO2 nanocomposites. The mechanical properties of the nanocomposites were also examined. It was found that the PAN/Na-MMT/SiO2 nanocomposites exhibit considerably enhanced moduli compared with the PAN/Na-MMT and PAN/SiO2 nanocomposites due to the synergistic reinforcing effect.