| 초록 |
Aerogels are light materials with highly porosity, large specific surface area and low thermal conductivity. Organic aerogels such as polyurethane (PU) aerogels, which have low thermal conductivity and excellent mechanical and chemical resistance, are attracting attention as alternatives to inorganic aerogels. In this study, PU aerogel was prepared by mixing diol and hexamethylene diisocyanate trimmer in solvent mixture of CH3CN and acetone, and thereafter by gelation and freeze-drying/ambient pressure-drying. Freeze-drying was applied by solvent exchange using tert-butanol while ambient pressure-drying was applied through pentane solvent exchange. Both methods work cost-effectively. Dioles with different chain lengths such as EG (ethylene glycol), Tri-EG, and Tetra-EG were used in our work to achieve better aerogel properties. The skeletal structure and mechanical and chemical properties of PU aerogels were analyzed according to the preparation conditions using SEM, UTM, and FT-IR. |
