Dispersion and improvement of organoclays in nanocomposites based on poly(propylene oxide)
This work is mainly concentrated on the preparation and characterization of poly(propylene oxide) (PPO)/organic clay nanocomposites. The effects of the nature of organoclays and the method of preparation have been elucidated to evaluate their morphological, structural and thermal properties. These nanocomposites were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, thermal analysis (differential scanning calorimetry) and thermogravimetric analysis (TGA). This study involved the use of an Algerian clay called ‘maghnite’ which was modified by an incorporation method using different concentrations of the surfactant cetyltrimethylammonium bromide (CTAB). Propylene oxide (PO) was polymerized in the presence of ethylene glycol and various proportions of organic clay ranging from 1%, 5% and 10% by weight. The structural study by XRD showed, at different loading rates of maghnite and PO in the preparation of PPO/maghnite nanocomposites, different morphologies: intercalated/exfoliated blend and intercalated/agglomerated. TGA showed that the intercalation of PPO at the montmorillonite (MMT)-CTA interface would be more advantageous since the required amount of 5% organic clay (by weight) ensures high thermal stability of the nanocomposites, and the glass transition temperature ( T g) of PPO/MMT nanocomposites is higher than that of PPO since this increase is due to the introduction of clay into the matrix which makes the nanocomposite more rigid.