Nanostructured Composites Based on Polyethylene–Polyamide Blends. II. Probing the Orientation in Polyethylene–Polyamide Nanocomposites and Their Precursors

Abstract

The present article discloses the orientation in some microfibrillar‐reinforced materials (MFC), as well as in their precursors as revealed by small‐angle x‐ray scattering (SAXS) of synchrotron radiation. Compatibilized and noncompatibilized polymer blends based on high‐density polyethylene (PE) and polyamide 12 (PA12) or polyamides 6 (PA6) taken in various proportions were prepared by consecutive melt blending, extruding, and cold drawing. These blends were, afterward, subjected to compression molding to obtain the MFC in which an isotropic and relaxed PE matrix were reinforced by differently oriented PA fibrils. The orientation of the latter was studied by means of two‐dimensional SAXS in a synchrotron as a function of the blends' chemical compositions and compatibilizations. Based on the analysis of the SAXS patterns, a model was proposed, explaining the role of the PA type and polyethylene‐co‐maleic anhydride compatibilizer in the orientation of the PE–PA precursors and composites during the various stages of preparation.