Control of pore size in ceramic foams: Influence of surfactant concentration

The role of sodium lauryl sulfate (SLS) on pore size of ceramic foams has been investigated using silica foams with 65–70% porosity prepared by a mechanical foaming and gelcasting method. Experiments were carried out to determine bubble size and stability of three-phase foams as well as the pore size of ceramic foams under a range of SLS concentration. Results suggested that pore size of ceramic foams is successfully controlled by changing the SLS concentration of three-phase foam slurries. The controllable range of pore size in this study was roughly 70–150 μm, which corresponded to the SLS concentration range between 7 × 10−3 and 7 × 10−2 M. Furthermore, it was found that the SLS concentration significantly influenced on the foam stability during post-foaming processes as well as the initial bubble size.