Hydrophobic silica wet gel and aerogel

Patent metadata

Field	Value
Publication number	US-2024351891-A1
Application number	US-202418636681-A
Country	US
Kind code	A1
Filing date	Apr 16, 2024
Priority date	Apr 20, 2023
Publication date	Oct 24, 2024
Grant date	—

Abstract

The invention provides hydrophobic silica wet gel, hydrophobic silica aerogel, and methods that can be used to form an enhanced hydrophobic silica aerogel sheet having an advantageous combination of properties. Some embodiments of the invention provide a hydrophobic silica aerogel having advantageous properties, such as desirable performance on visible transmission, haze, or both.

First claim

What is claimed is:

1 . A method of making a hydrophobic silica aerogel, comprising the steps of:
preparing a first solution by mixing tetramethyl orthosilicate and methanol; preparing a second solution by mixing methanol, ammonium hydroxide and water; mixing the first solution and the second solution together to form a mixed solution; allowing components in the mixed solution to react to form silica wet gel; preparing a third solution by mixing methyltrimethoxysilane and methanol; adding the third solution to the silica wet gel; allowing the third solution to react with the silica wet gel to form hydrophobic silica wet gel; and drying the hydrophobic silica wet gel to form hydrophobic silica aerogel; wherein the tetramethyl orthosilicate has a total weight percent of greater than or equal to 13.8% and less than or equal to 31% and the methyltrimethoxysilane has a total weight percent of greater than or equal to 3.2% and less than or equal to 4.6%, wherein total weight percent represents a total weight percent of a component in the first, second and third solutions.

2 . The method of claim 1 wherein:
the total weight percent of the tetramethyl orthosilicate is greater than or equal to 13.8% and less than or equal to 31%;
the total weight percent of the methyltrimethoxysilane is greater than or equal to 3.2% and less than or equal to 4.6%;
the methanol has a total weight percent of greater than or equal to 53.4% and less than or equal to 71.3%;
the water has a total weight percent of greater than or equal to 10.6% and less than or equal to 13.7%; and
the ammonium hydroxide has a total weight percent of greater than or equal to 0.034% and less than or equal to 0.126%.

3 . The method of claim 1 wherein:
the total weight percent of the tetramethyl orthosilicate is greater than or equal to 13.8% and less than or equal to 31%;
the total weight percent of the methyltrimethoxysilane is greater than or equal to 3.2% and less than or equal to 4.6%;
the methanol has a total weight percent of greater than or equal to 53.4% and less than or equal to 71.3%;
the water has a total weight percent of greater than or equal to 11% and less than or equal to 11.8%; and
the ammonium hydroxide has a total weight percent of greater than or equal to 0.034% and less than or equal to 0.038%.

4 . The method of claim 1 wherein the first solution comprises tetramethyl orthosilicate at a weight percent of greater than or equal to 38.1% and less than or equal to 68.4% and methanol at a weight percent of greater than or equal to 31.6% and less than or equal to 61.9%, the second solution comprises methanol at a weight percent of greater than or equal to 54.9% and less than or equal to 65.7%, water at a weight percent of greater than or equal to 33.9% and less than or equal to 44.7%, and ammonium hydroxide at a weight percent of greater than or equal to 0.10% and less than or equal to 0.42%, and the third solution comprises methanol at a weight percent of greater than or equal to 84.5% and less than or equal to 89.2% and methyltrimethoxysilane at a weight percent of greater than or equal to 10.8% and less than or equal to 15.5%.

5 . The method of claim 1 wherein the first solution comprises tetramethyl orthosilicate at a weight percent of greater than or equal to 38.1% and less than or equal to 68.4% and methanol at a weight percent of greater than or equal to 31.6% and less than or equal to 61.9%, the second solution comprises methanol at a weight percent of greater than or equal to 56.3% and less than or equal to 65.7%, water at a weight percent of greater than or equal to 34.2% and less than or equal to 43.5%, and ammonium hydroxide at a weight percent of greater than or equal to 0.10% and less than or equal to 0.15%, and the third solution comprises methanol at a weight percent of greater than or equal to 84.5% and less than or equal to 89.2% and methyltrimethoxysilane at a weight percent of greater than or equal to 10.8% and less than or equal to 15.5%.

6 . The method of claim 1 wherein the density of the hydrophobic silica aerogel is between 120 mg/cc and 200 mg/cc and the total weight percent of the tetramethyl orthosilicate is greater than or equal to 16.9% and less than or equal to 31%, and the total weight percent of the methyltrimethoxysilane is greater than or equal to 2.6% and less than or equal to 4.6%.

7 . The method of claim 6 wherein:
the total weight percent of the tetramethyl orthosilicate is greater than or equal to 16.9% and less than or equal to 31%;
the total weight percent of the methyltrimethoxysilane is greater than or equal to 2.6% and less than or equal to 4.6%;
the methanol has a total weight percent of greater than or equal to 53.4% and less than or equal to 68.5%;
the water has a total weight percent of greater than or equal to 10.6% and less than or equal to 13.7%; and
the ammonium hydroxide has a total weight percent of greater than or equal to 0.034% and less than or equal to 0.126%.

8 . The method of claim 6 wherein:
the total weight percent of the tetramethyl orthosilicate is greater than or equal to 16.9% and less than or equal to 31%;
the total weight percent of the methyltrimethoxysilane is greater than or equal to 3.1% and less than or equal to 4.6%;
the methanol has a total weight percent of greater than or equal to 53.4% and less than or equal to 68.5%;
the water has a total weight percent of greater than or equal to 11% and less than or equal to 11.5%; and
the ammonium hydroxide has a total weight percent of greater than or equal to 0.034% and less than or equal to 0.037%.

9 . The method of claim 6 wherein the first solution comprises tetramethyl orthosilicate at a weight percent of greater than or equal to 44.2% and less than or equal to 68.4% and methanol at a weight percent of greater than or equal to 31.6% and less than or equal to 55.8%, the second solution comprises methanol at a weight percent of greater than or equal to 54.9% and less than or equal 65%, water at a weight percent of greater than or equal to 34.6% and less than or equal to 44.7%, and ammonium hydroxide at a weight percent of greater than or equal to 0.10% and less than or equal to 0.42%, and the third solution comprises methanol at a weight percent of greater than or equal to 84.5% and less than or equal to 89.2% and methyltrimethoxysilane at a weight percent of greater than or equal to 10.8% and less than or equal to 15.5%.

10 . The method of claim 6 wherein the first solution comprises tetramethyl orthosilicate at a weight percent of greater than or equal to 44.2% and less than or equal to 68.4% and methanol at a weight percent of greater than or equal to 31.6% and less than or equal to 55.8%, the second solution comprises methanol at a weight percent of greater than or equal to 56.3% and less than or equal 65%, water at a weight percent of greater than or equal to 34.9% and less than or equal to 43.5%, and ammonium hydroxide at a weight percent of greater than or equal to 0.10% and less than or equal to 0.15%, and the third solution comprises methanol at a weight percent of greater than or equal to 84.5% and less than or equal to 89.2% and methyltrimethoxysilane at a weight percent of greater than or equal to 10.8% and less than or equal to 15.5%.

11 . The method of claim 1 wherein the density of the hydrophobic silica aerogel is between 120 mg/cc and 150 mg/cc and the total weight percent of the tetramethyl orthosilicate is greater than or equal to 16.9% and less than or equal to 24.7% and the total weight percent of the methyltrimethoxysilane is greater than or equal to 2.9% and less than or equal to 3.9%.

12 . The method of cla

Assignees

• Cardinal Cg Co

Inventors

• Chowdhury Reaz Ahmed
• Myli Kari B

Classifications

• B32B5/18

  characterised by features of a layer {of} foamed material · CPC title

• E06B3/66328

  of rubber, plastics or similar materials (E06B3/66314, E06B3/66323 and E06B3/66342 take precedence; transparent materials E06B3/66333) · CPC title

• E06B3/66319

  of rubber, plastics or similar materials · CPC title

• E06B3/66314

  of tubular shape (E06B3/66323 and E06B3/66333 take precedence) · CPC title

• E06B3/6715

  specially adapted for increased thermal insulation or for controlled passage of light (E06B3/66323 takes precedence; coating of glass pains C03C17/00; devices or arrangements for controlling the intensity, colour, phase, polarisation or direction of light G02F1/00) · CPC title