In‐situ synthesis of poly(ethylene terephthalate)/clay nanocomposites using TiO2/SiO2 sol‐intercalated montmorillonite as polycondensation catalyst

A novel organic montmorillonite, which could act as both polycondensation catalyst of poly(ethylene terephthalate) (PET) and filler of PET/clay nanocomposites, was prepared. Original montmorillonite was first treated with different amounts of poly(vinylpyrrolidone) (PVP), and then intercalated by TiO2/SiO2 sol to gain polycondensation catalytic activity. The acquired clay possessed excellent thermal stability and would not degrade during the polycondensation step. PET/clay nanocomposites were prepared via in‐situ polymerization using the organo‐clay as polycondensation catalysts. The morphologies of the nanocomposites were characterized by X‐ray diffraction and transmission electron microscope. The results indicated that the amount of PVP and TiO2/SiO2 sol strongly affected the dispersion state of the clay, and finally, partially exfoliated PET/clay nanocomposites were obtained. The nanocomposites had better properties than pure PET due to the incorporation of the delaminated clay layers. POLYM. ENG. SCI., 2009.