Thermoplastic polyolefin based polymer - blend-layered double hydroxide nanocomposites

Layered double hydroxides (LDHs) are a new class of promising nanomaterials which improve the physicochemical properties of the polymer matrix. The present work deals with the preparation of nanocomposites of ethylene vinyl acetate (EVA-28)/low density polyethylene (LDPE) blend (1:1 by wt.) with varying amounts of organomodified layered double hydroxide (DS-LDH) by solution blending. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) have been used to find out the dispersion of Mg-Al nanolayers in EVA/LDPE blend. This confirms complete exfoliation of Mg-Al nanolayers in EVA-28/LDPE/DS-LDH nanocomposites. The measurements of mechanical properties of these nanocomposites show maximum tensile strength for 3 wt.% of DS-LDH content. However, elongation at break for the nanocomposites remains lower for entire filler loading with respect to neat EVA/LDPE blend. Thermogravimetric analysis shows successive improvement in the thermal stability behavior of the nanocomposites with increasing the concentration of DS-LDH. The limiting oxygen index values are also improved with increasing DS-LDH concentration. Swelling property measurement shows that solvent resistance properties of the nanocomposites are better at low filler loading. (c) 2008 Elsevier Ltd. All rights reserved.