Effect of swelling agent on the physical properties of PET–clay nanocomposite materials prepared from melt intercalation approach

Abstract

A series of poly(ethylene terephathalate) (PET)/organo-modified clay nanocomposites were successfully prepared by melt intercalation through the twin-roller mixer. Two kinds of swelling agents are used as organo-modifiers of the pristine clay. Wide-angle X-ray diffraction (WAXRD) and transmission electron microscopy (TEM) were employed to study the morphology of the PET–clay nanocomposites. The quaternary alkylphosphonium salt (4-carboxybutyl) triphenylphosphonium bromide ( Φ 3P +-C 4)-modified clay was found to show better dispersion capability than that of quaternary alkylammonium salt hexadecyltrimethyl ammonium bromide (Me 3N +-C 16)-modified clay that existed in the polymer matrix. The thermo-mechanical properties were characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and dynamic mechanical analyzer (DMA). The optical clarity was examined by UV–visible transmission spectra. The better dispersion of ( Φ 3P +-C 4)-modified clay in PET leads to excellent improvement of physical properties such as optical clarity, thermal stability and mechanical strength of the PET–polymers than that of using (Me 3N +-C 16)-modified clay.