Nanostructure and micromechanical properties of reversibly crosslinked isotactic polypropylene/clay composites

Recent developments concerning the meth- odology used to prepare composites of iPP and nanoclays are reported. Conventional (reactive melt mixing) and in situ preparations were performed, and the structural prop- erties exhibited by the composites are discussed. Results suggest that the nanoclay could exhibit partial and, maybe, total exfoliation within the composites. Adhe- sion between the polymeric matrix and the nanoclay layers is similar to that obtained after grafting. The ex- perimental procedure used and the analysis performed by means of the wide-angle X-ray scattering and differ- ential scanning calorimetry techniques permit to describe, at nanoscale level, the contribution of the nanoclay to the polymer composite system. The micro- hardness values of the iPP-clay composites depend on the clay content and on the preparation method, and linearly correlate, according to the additivity law, with the degree of crystallinity. V C 2009 Wiley Periodicals, Inc. J Appl Polym Sci 115: 2654-2662, 2010