Poly(propylene)/PET/Undecyl Ammonium Montmorillonite Nanocomposites. Synthesis and Characterization

A natural bentonite rich in calcium montmorillonite (CaMMT) was initially purified and ion‐exchanged to obtain sodium montmorillonite (NaMMT). Both clays were organophillised by cationic exchange reaction with undecyl‐ammonium chloride, and characterized. Isotactic poly(propylene) (PP) was melt‐compounded with both the unmodified and the organophilic montmorillonites. The hybrids produced have been characterized structurally, thermally and mechanically. Maleic anhydride‐grafted PP (MAH‐g‐PP) was used as compatibilizer in some of the formulations. Homologous series of hybrids were also synthesized employing blends of PP/PET and compared with those of the pure PP to investigate possible beneficial effects due to the presence of small amounts of PET on the microstructure and properties of this kind of materials. The analysis of the results indicates some extension of both macromolecules intercalation and clay particles exfoliation in the hybrids prepared with the organophilic montmorillonite. The hybrids prepared with compatibilized PET/PP blends were found to have a better nanostructure.