The Effects of Organoclay on the Morphology and Balance Properties of an Immiscible Polypropylene/Natural Rubber Blend

The objective of this work is to study the effects of organoclay on the morphology and balance properties between strength and toughness of a blend based on polypropylene (PP) and natural rubber (NR). This nanocomposite blend (nanoblend) was prepared by melt extrusion technique. The results obtained show that at 3 wt % organoclay concentration there is a slight balance between strength and toughness of the blend. On the other hand, the results obtained by XRD analysis show that, at 3 wt % of organoclay loading, there is a shift towards low angles of the (001) plane diffraction peak. This shift means an intercalation of the macromolecular polypropylene/natural rubber blend chains between the clay platelets. The SEM study reveals that at 3 wt % organoclay concentration there is a uniform distribution of the elastomeric dispersed domains. TGA analysis revealed an improvement of the thermal stability of the composite containing 3 wt % organoclay. DSC study shows that at 3 wt % organoclay concentration, there is a decrease of the melting temperatures of the blend; this decrease can be explained by the intercalation of NR chains between organoclay platelets. This intercalation can hinder or disturb the physical transition of the intercalated PP chains. The simultaneous intercalation of PP and NR chains into organoclay galleries can be explained by the localization of the organoclay platelets at the interface between PP and NR domains as assessed by SEM examinations