Preparation and characterization of polystyrene/montmorillonite nanocomposite by melt intercalative compounding

Polymer composites based on modified montmorillonite (OMMT) and polystyrene (PS) were prepared with different compositions by melt processing. The pristine montmorillonite (MMT) was obtained from Algerian plant with a cation exchange capacity (CEC) of 119 meq/100g. The modification of MMT was carried out by treating with octadecylammonium cation. The polymer composites were characterized using different techniques such as X-ray diffraction (XRD), infrared spectrophotometery (IR), differential scanning calorimetery (DSC), thermal gravimetric analysis (TGA), and rheology and tensile measurements. The results were showed that, the basal space of the silicate layer increased, as determined by XRD, from 12.6 to 32.3 A. The microstructure was detected by X-ray patterns and transmission electronic microscopy (TEM) at 2 wt% OMMT, however, higher than 2 wt% OMMT reveals partial intercalation structure. The composite with 5 wt% was indicated the greatest improvement in thermal stability. The rheological properties of the PS/OMMT composites were investigated using ARES-rheometer operated in the dynamic mode with a parallel plate geometry. The storage and loss moduli were increased with increasing the clay content. The stress-at-break is also improved relatively compared to the virgin polystyrene in our experimental conditions.