초록 |
Aerogel have attracted a lot of attention due to their unique and excellent properties such as lightness, low thermal conductivity, and low dielectric constant. Since the silica aerogels are typically brittle, and increasing attention is being paid to polymer aerogels to achieve better mechanical performance and expand the applicability. PI aerogel is generally prepared by supercritical drying method. In this presentation, we provide a new approach to control the porosity and pore structure of PI aerogels by adjusting solvent properties during the solvent exchange process. After applying a conventional vacuum drying, PI aerogels with controlled porosity in a various range (50 ~ 85%) were produced. Based on our approach, it was possible to fabricate PI aerogels with various dielectric constants between 1.2 and 2.5, while exhibiting high dielectric strength greater than 10kV/mm. Furthermore, PI aerogels were also produced in the form of films with various thickness. |