Control of bubble growth in Nanocellular Foams

In this study, we used nanosilica as a nucleating agent and tried to reduce cell size by loading more amount of the nanoparticles Polystyrene-Nanosilica Nanocomposites with 1, 2, 4, 6, 8 and 10 wt. % of nanoparticles were prepared using a solution mixing method. Then, the nanocomposites were foamed at the saturation pressure of 20Mpa and temperature of 70 °C in a high pressure autoclave. The average size of cells were measured from scanning electron microscopy pictures. The results showed that while nanoparticles amount increases from 1 to 10 wt. %, the cell average size of foamed nanocomposites decreases from 217 to 100 nm. The average size of cells for net polystyrene foams was 503 nanometer. Heterogeneous nucleation due to adding nanoparticles to system enhanced initial cell nucleation and increased number of cells at the final structure of foams

Keywords:

Cell Size , Growth , Nanosilica , Nanocellular Foams , Nanocomposite