Aerogel composite
The present disclosure relates to an aerogel composite and an insulation member including the same, wherein the aerogel composite may maintain insulation constant without significant degradation even when exposed to a pressurization environment. The aerogel composite includes a substrate including a plurality of discrete fibers and voids between the fibers; and silica aerogel including a plurality of aerogel particles positioned on the fiber and in the voids between the fibers, and having a network structure including one or more pores, wherein when a pressure of 150 N/cm 2 is applied in a thickness direction with respect to the aerogel composite, a volume ratio of aerogel including pores and voids between discrete fibers per unit volume of the aerogel composite is 0.85 times to 1 time compared to before the pressure was applied.
1 . An aerogel composite comprising:
a substrate including a plurality of discrete fibers and voids between the fibers; and
silica aerogel including a plurality of aerogel particles positioned on the fiber and in the voids between the fibers, and having a network structure including one or more pores,
wherein the volume ratio of the aerogel including pores and the voids per unit volume of the aerogel composite is 88% to 98%,
wherein a total volume ratio of the fibers per unit volume of the aerogel composite is from 2% to 12%,
wherein when a pressure of 150 N/cm 2 is applied in a thickness direction with respect to the aerogel composite, a volume ratio of aerogel including pores and voids between discrete fibers per unit volume of the aerogel composite is 0.85 times to 1 time compared to before the pressure was applied,
wherein when a pressure of 300 N/cm 2 is applied in a thickness direction with respect to the aerogel composite, the volume ratio of the aerogel including pores and the voids per unit volume of the aerogel composite is 0.80 times to 1 time compared to before the pressure was applied,
wherein when a pressure of 150 N/cm 2 is applied to a cross-section of the aerogel composite, the heat transmission coefficient after the compression is greater than 1 time and less than or equal to 1.5 times the heat transmission coefficient before the compression,
wherein when a pressure of 300 N/cm 2 is applied to a cross-section of the aerogel composite, the heat transmission coefficient after the compression is greater than 1 time and less than or equal to 1.8 times the heat transmission coefficient before the compression.
2 . The aerogel composite of claim 1 , wherein when a pressure of 300 N/cm 2 is applied in the thickness direction with respect to the aerogel composite, the volume ratio of the aerogel including pores and the voids per unit volume of the aerogel composite is 0.89 times to 1 time the volume ratio thereof when a pressure of 150 N/cm 2 is applied.
3 . The aerogel composite of claim 1 , wherein when each of a pressure of 150 N/cm 2 and a pressure of 300 N/cm 2 are applied to the aerogel composite to compress the aerogel composite, the heat transmission coefficient before and after the compression satisfy Equation 2 below:
{
(
Heat
transmission
coefficient
(
a
)
before
and
after
compression
-
Average
value
(
b
)
of
heat
transmission
coefficients
before
and
after
compression
)
}
=
(
Average
value
(
b
)
of
heat
transmission
coefficients
before
and
after
compression
)
×
A
[
Equation
2
]
wherein in Equation 2, the heat transmission coefficient (a) before and after compression refers to a heat transmission coefficient obtained after compression with an intensity of 0 N/cm 2 , 150 N/cm 2 , or 300 N/cm 2 in the thickness direction of the aerogel composite; the average value (b) of heat transmission coefficients before and after compression refers to an average value of the heat transmission coefficient of an unpressurized aerogel composite and heat transmission coefficients obtained after compressing the aerogel composite with an intensity of each of 150 N/cm 2 and 300 N/cm 2 ; and the A is a real number of −0.30 to +0.30.
4 . The aerogel composite of claim 3 , wherein the A is a real number of −0.25 to +0.25.
5 . The aerogel composite of claim 1 , wherein when each of a pressure of 150 N/cm 2 or 300 N/cm 2 is applied to the aerogel composite, a rate of change (B) in heat transmission coefficient after compression per unit applied pressure obtained after the compression satisfies Equation 3 below:
B
=
❘
"\[LeftBracketingBar]"
(
heat
transmission
coefficient
after
compression
with
a
pressure
of
x
-
heat
transmission
coefficient
after
compression
with
a
pressure
of
y
)
/
(
x
-
y
)
❘
"\[RightBracketingBar]"
[
Equation
3
]
wherein in Equation 3 above, x is a pressure intensity of 150 N/cm 2 or 300 N/cm 2 , y is 0, and the B is a real number of 0 to 2.0×10 −2 .
6 . The aerogel composite of claim 5 , wherein the x is 150 N/cm 2 , y is 0, and the B is a real number of 0 to 1.5×10 −2 .
7 . The aerogel composite of claim 5 , wherein the x is 300 N/cm 2 , y is 0, and the B is a real number of 0 to 1.0×10 −2 .
8 . The aerogel composite of claim 1 , wherein the fiber substrate and the aerogel in the aerogel composite are included at a weight ratio of 1:0.4 to 2.
9 . The aerogel composite of claim 1 , wherein a density of the aerogel composite is 0.15 g/cm 3 to 0.35 g/cm 3 .
10 . A heat insulation member comprising the aerogel composite of claim 1 .
11 . The aerogel composite of claim 10 , wherein the heat insulation member further comprises a support member positioned on at least one surface of an upper surface of the aerogel composite and a lower surface thereof.