Han-Xiong Huang, Hong-Fei Xu, and Jian-Kang Wang. Center of Polymer Processing Equipment and Intellectualization, College of Industrial Equipment and Control Engineering, South China University of Technology, Guangzhou, China
The supercritical carbon dioxide foaming behaviors of polypropylene/polystyrene (PP/PS) blends and their nanocomposites with 3 wt% nanoclay using a pressure vessel were investigated. The cell size increased and the cell density decreased with the increase of PS content. Dispersed PS phase with more uniform distribution was favorable to produce much more uniform cellular structure. The addition of a small amount of nanoclay, which acts as a nucleation agent, reduced the cell size and increased the cell density of PP/PS blends further. Microcellular foams with mean cell diameters of 0.80-7.13 µm and cell densities of 2.50x109-3.96x1011 cells/cm3 were produced from blends and their nanocomposites.