Microcellular Foaming of Low-Density Polyethylene Using Nano-CaCO3 as a Nucleating Agent

In this study, microcellular foaming of low-density polyethylene (LDPE) using nano-calcium carbonate (nano-CaCO3) were carried out. Nanocomposite samples were prepared in different content in range of 0.5-7 phr nano-CaCO3 using a twin screw extruder. X-ray diffraction and scanning electron microscopy (SEM) were used to characterize of LDPE/nano-CaCO3 nanocomposites. The foaming was carried out by a batch process in compression molding with azodicarbonamide (ADCA) as a chemical blowing agent. The cell structure of the foams was examined with SEM, density and gel content of different samples were measured to compare difference between nanocomposite microcellular foam and microcellular foam without nanomaterials. The results showed that the samples containing 5 phr nano-CaCO3 showed microcellular foam with the lowest mean cell diameter 27 mu m and largest cell density 8 x 10(8) cells/cm(3) in compared other samples. POLYM. COMPOS., 32:1718-1725, 2011. (C) 2011 Society of Plastics Engineers