A semi-rigid polyurethane foam and a silsesquioxane aerogel composite for commercial thermal insulator

초록

Unique properties such as extraordinary low thermal conductivity, enormous specific surface area, or extremely low density of an aerogel are resulted from network structure of the aerogel. We surmise that one of parameters affecting the network structure of the aerogel is solvent (especially, the ratio of carbon to hydroxy group). To prove this presumption, solvents having various ratios carbon to hydroxyl group were used in synthesizing polymethylsilsesquioxane (PMSQ) aerogel derived from methyltrimethoxysilane precursor. Methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, benzyl alcohol, and 1-decanol of which ratios of carbon to hydroxy group were 1:1, 2:1, 3:1, 7:1 were used as same volume. The more carbon ratio increased, the more transmittance of PMSQ aerogel increased. Moreover, network structure of PMSQ aerogel had clear tendency by carbon ratio of solvents. This work will give inspiration in sol-gel synthesis