LAUSR

Abstract The influences of nanosized carbon black (CB) on the morphology of immiscible cocontinuous LLDPE/PS blends and their foaming behavior under the sc-CO2 batch foaming was studied. The morphologies and cellular structures of LLDPE/PS blends and LLDPE/PS/CB nanocomposites were characterized by scanning electron microscope (SEM). The results indicated that the introduction of CB nanoparticles could effectively improve foaming ability of LLDPE/PS=50/50 blends, when enough amount of CB nanofillers was added. This was ascribed to the morphology transformation from cocontinuous structure to sea-island structure due to the presence of CB nanofillers. Furthermore the critical amount of CB for dramatically improving the foaming capacity depended on the foaming temperature. In contrast, the addition of CB in the LLDPE/PS blends with spherical dispersed phase (such as 80/20 or 20/80, by weight) did not dramatically change the foaming behavior of the blends.