Imparting the flame retardancy to the polymethylsilsesquioxane (PMSQ) aerogel monolith by introducing 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)-derivatives.

초록

Aerogel is a synthetic porous ultralight material derived from a gel, in which the liquid component for the gel has been replaced with a gas without significant collapse of the gel structure. The result is a solid with extremely low density and extremely low thermal condu ctivity. Aerogels are produced by extracting the liquid component of a gel through supercritical drying or freeze-drying. This allows the li quid to be slowly dried off without causing the solid matrix in the gel to collapse from capillary action, as would happen with convention al evaporation. Aerogel is a material that is 99.8% air. Aerogels hav e a porous solid network that contains air pockets, with the air pock ets taking up the majority of space within the material. The dearth o f solid material allows aerogel to be almost weightless. Aerogels ar e good thermal insulators through heat transfer, conduction, and co nvection. They are good conductive insulators because they are co mposed almost entirely of gases, which are very poor heat conduct ors. Silica aerogel is an especially good insulator because silica is also a poor conductor of heat; a metallic or carbon aerogel, on the other hand, would be less effective. They are good convective inhib itors because air cannot circulate through the lattice. Aerogels are poor radiative insulators because infrared radiation which transfers heat passes through them.