Flexible composite aerogel and process for producing same

Patent metadata

Field	Value
Publication number	US-10294165-B2
Application number	US-201415118380-A
Country	US
Kind code	B2
Filing date	Feb 12, 2014
Priority date	Feb 12, 2014
Publication date	May 21, 2019
Grant date	May 21, 2019

Abstract

The present invention relates to a flexible composite organic aerogel ( 1 ) comprising:
a textile reinforcement ( 5 ), an organic aerogel ( 3 ) placed within said textile reinforcement ( 3 ),

said organic aerogel ( 3 ) being based on a resin resulting at least in part from polyhydroxybenzene(s) R and formaldehyde(s) F,

said organic aerogel ( 3 ) being a polymeric organic gel comprising at least one water-soluble cationic polyelectrolyte,

or said organic aerogel ( 3 ) being a pyrolysate of said gel in the form of a porous carbon monolith comprising the product of the pyrolysis of said at least one water-soluble cationic polyelectrolyte P,

said organic aerogel ( 3 ) exhibiting a specific thermal conductivity of between 10 and 40 mW·m −1 ·K −1 at atmospheric pressure.

First claim

The invention claimed is:

1. A flexible composite organic aerogel, comprising:
a textile reinforcement; and
an organic aerogel placed within the textile reinforcement,
wherein:
the organic aerogel is based on a resin resulting at least in part from at least one polyhydroxybenzene R and at least one formaldehyde F; and
the organic aerogel is:
(i) a polymeric organic gel comprising at least one water-soluble cationic polyelectrolyte P, or
(ii) the organic aerogel is a pyrolysate of the polymeric organic gel in the form of a porous carbon monolith comprising a product of pyrolysis of the at least one water-soluble cationic polyelectrolyte P,

wherein the at least one water-soluble cationic polyelectrolyte P is an organic polymer selected from the group consisting of a quaternary ammonium salt, a poly(vinylpyridinium chloride), a polyethyleneimine, a polyvinylpyridine, a poly(allylamine hydrochloride), a poly(trimethylammonioethyl methacrylate chloride), a poly(acrylamide-co-dimethylammonium chloride) and mixtures thereof; and
the organic aerogel exhibits a specific thermal conductivity of between 10 and 40 mW·m −1 ·K −1 at atmospheric pressure,
wherein the flexible composite organic aerogel comprises a product of a polymerization reaction in an aqueous solvent W of the at least one polyhydroxybenzene R and the at least one formaldehyde F, in the presence of the at least one water-soluble cationic polyelectrolyte P dissolved in the aqueous solvent W and in the presence of a catalyst,
wherein the product of the polymerization reaction comprises the at least one water-soluble cationic polyelectrolyte P in a ratio by weight according to P/(R+F) of 2% to 10%, with respect to the at least one polyhydroxybenzene R and the at least one formaldehyde F, and
wherein the organic aerogel has a density of between 0.01 and 0.4 g/cm 3 .

2. The flexible composite organic aerogel of claim 1 , wherein the at least one water-soluble cationic polyelectrolyte P is a salt comprising units resulting from a quaternary ammonium of a poly(diallyldimethylammonium halide).

3. The flexible composite organic aerogel of claim 1 , wherein the product of the polymerization reaction comprises 0.2% to 2% mass fraction of the at least one water-soluble cationic polyelectrolyte P.

4. The flexible composite organic aerogel of claim 1 , wherein the product of the polymerization reaction comprises the at least one water-soluble cationic polyelectrolyte P in a ratio by weight according to P/(R+F+W) ratio by weight of 0.3% to 2%, with respect to the polyhydroxybenzene R, the at least one formaldehyde R and the aqueous solvent W %.

5. The flexible composite organic aerogel of claim 1 , wherein the organic aerogel further exhibits at least one of the following properties:
a specific surface of between 400 m 2 /g and 1200 m 2 /g;
a pore volume of between 0.1 cm 3 /g and 3 cm 3 /g;
a mean pore diameter of between 3 nm and 30 nm.

6. The flexible composite organic aerogel of claim 1 , wherein, when the organic aerogel is the polymeric organic gel comprising the at least one water-soluble cationic polyelectrolyte P, the textile reinforcement is produced with organic fibers having a moisture uptake content of greater than or equal to 5% and having a chemical affinity for the said organic aerogel.

7. The flexible composite organic aerogel of claim 6 , wherein the organic fibers or filaments of the textile reinforcement are selected from the group consisting of
a meta-aramid fiber,
an oxidized polyacrylonitrile fiber,
a polyamide-imide fiber,
a phenolic fiber,
a polybenzimidazole fiber, and
a polysulfonamide fiber.

8. The flexible composite organic aerogel of claim 6 , wherein the textile reinforcement is a nonwoven textile.

9. The flexible composite organic aerogel of claim 6 , wherein the textile reinforcement is a woven textile.

10. The flexible composite organic aerogel of claim 6 , wherein the textile reinforcement is a textile in three dimensions.

11. The flexible composite organic aerogel of claim 1 , wherein, when the organic aerogel is a pyrolysate in the form of a porous carbon monolith comprising the product of the pyrolysis of the at least one water-soluble cationic polyelectrolyte P, the textile reinforcement is produced with inorganic fibers which are resistant to the pyrolysis temperature.

12. The flexible composite organic aerogel of claim 11 , wherein the inorganic fibers or filaments of the textile reinforcement are selected from the group consisting of
a glass fiber,
a basalt fiber,
a ceramic fiber,
a silica fiber, and
a silicon carbide fiber.

13. A process for manufacturing the flexible composite organic aerogel of claim 1 , the process comprising:
a) polymerizing at least one polyhydroxybenzene R and at least one formaldehyde F in an aqueous solvent W, in the presence of at least one cationic polyelectrolyte P dissolved in the aqueous solvent W and in the presence of a catalyst, said polymerizing occurring within the textile reinforcement, to obtain a solution;
b) gelling the solution within the textile reinforcement in order to obtain a gel; and
c) drying of the textile reinforcement impregnated with the gel obtained in b) to obtain a dried gel,
wherein the at least one water-soluble cationic polyelectrolyte P is an organic polymer selected from the group consisting of a quaternary ammonium salt, a poly(vinylpyridinium chloride), a polyethyleneimine, a polyvinylpyridine, a poly(allylamine hydrochloride), a poly(trimethylammonioethyl methacrylate chloride), a poly(acrylamide-co-dimethylammonium chloride) and mixtures thereof,
wherein the at least one water-soluble cationic polyelectrolyte P is used
according to a P/(R+F) ratio by weight, with respect to the polyhydroxybenzene R and formaldehyde F, of between 2% and 10%.

14. The manufacturing process of claim 13 , further comprising pyrolyzing the dried gel, in order to obtain a porous carbon.

15. The manufacturing process of claim 13 , wherein:
the polymerizing a) occurs at ambient temperature, by

dissolving the at least one polyhydroxylbenzene R and the at least one water-soluble cationic polyelectrolyte P in the aqueous solvent W, and then adding, to the solution, the at least one formaldehyde F and an acidic or basic catalyst, before pouring the solution over the textile reinforcement; and
the gelling b) occurs by curing impregnated textile reinforcement in an oven.

16. The manufacturing process of claim 13 , wherein the drying c) occurs by drying with air in order to obtain a polymeric organic gel further exhibiting at least one of the following conditions:
a specific surface of between 400 m 2 /g and 1200 m 2 /g;
a pore volume of between 0.1 cm 3 /g and 3 cm 3 /g;
a mean pore diameter of between 3 nm and 30 nm.

Assignees

• Hutchinson

Inventors

• Swoboda Benjamin
• Huillet Cedric
• Sonntag Philippe
• Van Eibergen Arthur

Classifications

• C04B38/0032 Primary

  one of the precursor materials being a monolithic element having approximately the same dimensions as the final article, e.g. a paper sheet which after carbonisation will react with silicon to form a porous silicon carbide porous body · CPC title

• C04B35/806

  Chemistry & Metallurgy · mapped topic

• C01B32/00

  Carbon; Compounds thereof (C01B21/00, C01B23/00 take precedence; percarbonates C01B15/10; carbon black C09C1/48) · CPC title

• C04B2111/00612

  as one or more layers of a layered structure · CPC title

• C04B2111/28

  Fire resistance, i.e. materials resistant to accidental fires or high temperatures · CPC title