The Crystallinity Behavior of Polyethylene/Clay Nanocomposites Under the Influence of Water-Assisted Melt Blending

High-density polyethylene (HDPE)/clay nanocomposites were prepared via water-assisted and conventional melt blending. The influence of exfoliated/intercalated domains on crystallinity of nanocomposites was then investigated. X-ray diffraction and electron microscopy evidenced for enhanced intercalation and partial exfoliation of clay platelets pursuing rheological measurements. The methane permeability of water-injected nanocomposites was lower compared to melt-blended specimens implying the influence of intercalated domains. A theoretical/experimental analysis was performed to roughly determine the lamellar thickness distribution of the crystalline regions. Contribution of clay platelets to crystallization mechanisms was indicative of clay impact as heterogeneous nucleating agent, whereas mechanical properties were dependent on interface situation.