Abstract
Isotactic polypropylene (iPP) and iron oxide (Fe~3~O~4~) nanocomposites were mixed by masterbatch blending technique in a single screw extruder machine. The concentrations of Fe~3~O~4~ in the iPP/Fe~3~O~4~ nanocomposites were 0.5, 1, 2, and 5% by weight. The influence of Fe~3~O~4~ nanoparticles on the effectiveness of nucleation, morphology, mode of crystallization, and crystallinity of iPP were studied by differential scanning calorimetry (DSC) and polarized light microscopy (PLM). The introduction of Fe~3~O~4~ nanoparticles in the iPP matrix inhibited the formation of Ξ² crystals, and caused a shift in the melting point to higher values. The magnitude of the shift was up to 20β21Β°C which indicates that using the masterbatch technique leads to an enhancement of the dispersion process of the Fe~3~O~4~ nanoparticle and the formation of less agglomerates in the iPP/Fe~3~O~4~ nanocomposites. The percentage crystallinity, X~c~, increased at the low cooling rates of 1 and 2Β°C/min. At higher cooling rates of 5, 10, and 20Β°C/min, the masterbatch technique produced nanocomposites of X~c~ with nonuniform trends. The overall crystallization rate enhancement for the iPP/Fe~3~O~4~ nanocomposites is attributed to the presence of Fe~3~O~4~ nanoparticles as a nucleating agent which have no significant effect on the growth rate of iPP crystals. Β© 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010