	US 11,932,745 B2
	Water co-catalyst for polyimide processes
Redouane Begag, Hudson, MA (US); Roxana Trifu, Worcester, MA (US); Nicholas A. Zafiropoulos, Wayland, MA (US); Harris R. Miller, Sharon, MA (US); George L. Gould, Mendon, MA (US); and Nicholas Leventis, Worcester, MA (US)
Assigned to Aspen Aerogels, Inc., Northborough, MA (US)
Filed by Aspen Aerogels, Inc., Northborough, MA (US)
Filed on Dec. 9, 2021, as Appl. No. 17/546,529.
Claims priority of provisional application 63/124,454, filed on Dec. 11, 2020.
Prior Publication US 2022/0185985 A1, Jun. 16, 2022
Int. Cl. C01B 32/00 (2017.01); C04B 35/524 (2006.01); C04B 35/634 (2006.01); C04B 38/00 (2006.01); C08G 73/00 (2006.01); C08G 73/10 (2006.01); C08J 9/28 (2006.01); C08J 9/36 (2006.01); C08K 5/09 (2006.01); C08K 5/3432 (2006.01)

CPC C08J 9/286 (2013.01) [C08G 73/1007 (2013.01); C08G 73/1067 (2013.01); C08G 73/1085 (2013.01); C08J 9/36 (2013.01); C08K 5/09 (2013.01); C08K 5/3432 (2013.01); C08J 2201/0422 (2013.01); C08J 2201/0482 (2013.01); C08J 2205/026 (2013.01); C08J 2205/042 (2013.01); C08J 2205/044 (2013.01); C08J 2379/08 (2013.01)]

34 Claims

1. A method of forming a polyimide gel, the method comprising:

a) providing a tetracarboxylic acid dianhydride and a multifunctional amine;

b) adding the tetracarboxylic acid dianhydride and the multifunctional amine to an organic solvent to form a solution;

c) allowing the tetracarboxylic acid dianhydride and the multifunctional amine to react in solution, forming a solution of a polyamic acid sol;

d) adding a dehydrating agent, a monoamine, and water to the solution of the polyamic acid sol, forming a gelation mixture and allowing the gelation mixture to gel to form the polyimide gel, wherein the water is added at a molar ratio of water to the tetracarboxylic acid dianhydride from about 5 to about 500.