SYNTHESIS AND CHARACTERIZATION OF POLYPROPYLENE-SILICA, ALUMINA AND TITANIA NANOPARTICLES, PREPARED BY MELTING

ABSTRACT Polypropylene composites with 5 to 10% of SiO 2 , Al 2 O 3 y TiO 2 nanoparticles were synthesized. The oxides were obtained using the sol-gel technique and were added to the molten polypropylene. The morphology of nanoparticles was observed by scanning electron microscopy and showed that the incorporation of TiO 2 and SiO 2 gels produces high dispersion of the filler, while the use of Al 2 O 3 results in aggregates of these nanoparticles in the polymer matrix. The X-ray diffractogram of the composites revealed a displacement of characteristics lines of polypropylene and an increment of the interplanar spaces, indicating some interaction between the components and the predominance intercalation of oxides. Through FT-IR it was noticed the presence of functional groups attributable to the filler nanoparticles.The crystallization, the fusion behaviour and the thermal stability of the composites was studied using differential scanning calorimetry and thermogravimetric analysis it was found a reduction in the crystallization temperature and increment in the thermal stability of the polypropylene matrix due to the action of the silica, alumina an titania nanoparticles.