| 초록 |
Low density, mechanically strong, highly porous polyurea aerogels were synthesized by solution polymerization of amine and isocyanate. The polyurea wet gels were obtained after the reaction, and underwent CO2 supercritical fluid drying to obtain lightweight and porous polyurea aerogels. The pore size, morphology, compressive strength and surface area of aerogels were characterized by SEM, UTM and BET measurements. Thermal conductivity of polyurea aerogels was measured via Heat Flow Meter. The polyurea aerogels have densities in the range of 0.17-0.3 g/cm3, low shrinkage(＜5%), little dustiness and BET surface area as high as 314.9 m2/g. The monolithic structure and little brittleness of the these materials were revealed by compression test. Thermal conductivity and TGA analysis also suggest that they have good thermal insulation and stability. Due to high surface area and porosity of polyurea aerogels, they are one of promising candidates for various thermal insulating applications. |
