Aerogel
The present invention pertains to an aerogel having a thermal conductivity of 0.03 W/m·K or less and a compressive elasticity modulus of 2 MPa or less at 25° C. under atmospheric pressure.
1. An aerogel having a thermal conductivity of 0.03 W/m·K or less and a compressive elasticity modulus of 2 MPa or less at 25° C. under atmospheric pressure, wherein a ratio Q+T:D of a signal area derived from Q and T to a signal area derived from D is from 1:0.01 to 1:05 when in a solid 29 Si-NMR spectrum as measured by using DD/MAS method, silicon-containing bonding units of Q, T, and D are defined below:
Q: a silicon-containing bonding unit comprising four oxygen atoms that are bonded to one silicon atom;
T: a silicon-containing bonding unit comprising three oxygen atoms and one hydrogen atom or one mono-valent organic group that are bonded to one silicon atom; and
D: a silicon-containing bonding unit comprising two oxygen atoms and two hydrogen atoms or two mono-valent organic groups that are bonded to one silicon atom,
providing that the organic group is a mono-valent organic group where an atom bonded to a silicon atom is a carbon atom.
2. The aerogel according to claim 1 , having a recovery rate from deformation of 90% or more.
3. The aerogel according to claim 1 having a maximum compressive deformation rate of 80% or more.
4. The aerogel according to claim 1 , from drying a wet gel, the wet gel being formed from a sol comprising at least one member selected from the group consisting of a polysiloxane compound having a reactive group within a molecule thereof and a hydrolyzed product of said polysiloxane compound.
5. The aerogel according to claim 1 , having a recovery rate from deformation of 90% or more, calculated from the following:
Recovery rate from deformation=( d 3 −d 2)/( d 1 −d 2)×100
wherein d1 is a thickness of a sample of the aerogel before application of a load, d2 is a thickness of the sample at a maximum applied load of 500 N or when the sample is destroyed, and d3 is a thickness of the sample after removal of the load.
6. The aerogel according to claim 1 , wherein the aerogel comprises no mono-valent organic group including an amino group, and a carbon atom bonded to a silicon atom.