Energy efficient soundproofing window retrofits
Described herein are window retrofits including a monolithic silica aerogel slab having (i) an average haze value of <5% as calculated in accordance with ASTM standard D1003-13 and (ii) a U-factor of <0.5 BTU/sf/hr/° F., and a transparent polymer envelope sealed at an internal pressure of ≤1 atmosphere, wherein the monolithic silica aerogel slab is encapsulated in the transparent polymer envelope. The monolithic aerogel slab can have a transmittance >94% at 8 mm thickness. The window retrofit can be bonded to a glass sheet.
1. A window retrofit comprising:
a monolithic silica aerogel slab having (i) an average haze value of <5% as calculated in accordance with ASTM standard D1003-13 and (ii) a U-factor of <0.5 BTU/sf/hr/° F.; and
a transparent polymer envelope sealed at an internal pressure of ≤1 atmosphere, wherein the monolithic silica aerogel slab is encapsulated in the transparent polymer envelope.
2. The window retrofit of claim 1 , wherein the monolithic aerogel slab has a transmittance >94% at 8 mm thickness.
3. The window retrofit of claim 2 , wherein the monolithic aerogel slab has a transmittance >96% at 3 mm thickness.
4. The window retrofit of claim 1 , further comprising a low-emissivity coating disposed on a surface of the transparent polymer envelope.
5. The window retrofit of claim 1 , further comprising an anti-reflective coating disposed on a surface of the transparent polymer envelope.
6. The window retrofit of claim 1 , further comprising:
a glass sheet, the monolithic silica aerogel slab being bonded to the glass sheet,
wherein the transparent polymer envelope encapsulates the monolithic silica aerogel slab bonded to the glass sheet.
7. The window retrofit of claim 1 , wherein the slab has the U-factor of <0.5 BTU/sf/hr/° F. at an external temperature of −15° C. or greater.
8. The window retrofit of claim 1 , wherein the monolithic silica aerogel slab has a porosity of at least 90%.
9. The window retrofit of claim 1 , wherein the monolithic silica aerogel slab has a density selected from a range of 0.1 g/cm 3 to 0.2 g/cm 3 .
10. The window retrofit of claim 1 , wherein the monolithic silica aerogel slab has a pore volume selected from a range of 2000 cm 3 /g to 4000 cm 3 /g.
11. The window retrofit of claim 1 , wherein the monolithic silica aerogel slab has a specific surface area selected from a range of 500 m 2 /g to 1000 m 2 /g.
12. The window retrofit of claim 1 , wherein the monolithic silica aerogel slab has a thermal conductivity selected from a range of 0.005 W/m·K to 0.025 W/m·K.
13. The window retrofit of claim 1 , wherein the monolithic silica aerogel slab comprises cross-linked polymers.
14. The window retrofit of claim 1 , wherein the monolithic silica aerogel slab has an average sound transmission loss of 10 dB or greater at one or more frequencies selected from a range of 50 Hz to 1600 Hz.
15. The window retrofit of claim 1 , wherein the monolithic silica aerogel slab has a compressive strength of more than 2 MPa.
16. The window retrofit of claim 1 , wherein the monolithic silica aerogel slab has a bending strength of more than 1 MPa.
17. The window retrofit of claim 1 , wherein the monolithic silica aerogel slab has a Young's modulus of more than 5 MPa.
18. A method for producing a window retrofit, the method comprising:
forming a monolithic silica aerogel slab; and
encapsulating the monolithic silica aerogel slab in a polymer to define the window retrofit.
19. The method of claim 18 , wherein encapsulating the monolithic silica aerogel comprises:
laminating the monolithic silica aerogel slab with the polymer to define a polymer envelope.
20. The method of claim 18 , further comprising:
prior to the encapsulating step, bonding the monolithic silica aerogel slab to a glass sheet,
wherein, after encapsulation, the polymer encapsulates the monolithic silica aerogel slab and the glass sheet.