# US 10,501,579 B2 · Poly(amic acid) synthesis and conversion to high molecular weight polyimide

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,501,579 B2
- Document ID: US10501579B2
- Status: Granted
- Kind: B2
- Application number: 15/551,644
- Filed: 2016-02-18
- Published: 2018-01-25
- Granted: 2019-12-10
- Earliest claimed: 2015-02-20
- Assignees: Sabic Global Technologies B.V.
- Applicants: SABIC Global Technologies B.V.
- Inventors: Viswanathan Kalyanaraman
- Web page: https://patentgrep.com/patent/US10501579B2

## CPC

- C08G 73/1032: {characterised by the solvent(s) used}
- C08G 73/1017: {in the form of (mono)amine}
- C09D 179/08: Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
- C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D)

## Abstract

A process is disclosed for synthesis of a poly(amic acid), including reacting a dianhydride and a diamine in the presence of a tertiary amine, tertiary ammonium salt, tertiary ammonium hydroxide, secondary amine, secondary ammonium salt, secondary ammonium hydroxide, quaternary ammonium salt, quaternary ammonium hydroxide, ammonium hydroxide, or a combination comprising at least one of the foregoing, in water, at a temperature of 60 C to 180 C, or 60 C to 100 C, or 100 C to 180 C, under an inert atmosphere, with agitation, to produce an aqueous poly(amic acid).

## Claims

### Claim 1

A process for synthesis of a poly(amic acid), the process comprising:
reacting a dianhydride and a diamine in the presence of a higher monoamine comprising tertiary amine, tertiary ammonium salt, tertiary ammonium hydroxide, secondary amine, secondary ammonium salt, secondary ammonium hydroxide, quaternary ammonium salt, quaternary ammonium hydroxide, ammonium hydroxide, or a combination comprising at least one of the foregoing, in a reaction medium comprising at least 95 volume percent water, at a temperature of 80° C. to 180° C., under an inert atmosphere, with agitation, to produce an aqueous poly(amic acid).

### Claim 2 (depends on 1)

The process of claim 1,
wherein the dianhydride is bisphenol A dianhydride, pyromellitic dianhydride, 3,3′,4,4′-biphenyl dianhydride, 3,3′,4,4′-benzophenone dianhydride, 3,3′,4,4′-oxydiphthalic dianhydride, 1,4-bis(3,4 dicarboxyl phenoxy)benzene dianhydride, 1,3-bis(2,3-dicarboxyphenoxy)benzene dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, or a combination comprising at least one of the foregoing.

### Claim 3 (depends on 1)

The process of claim 1, wherein the diamine is meta-phenylene diamine, para-phenylene diamine, 4,4′-diaminodiphenylene ether, oxydianiline, 4,4′-diamino-3,3′-dimethyl diphenyl methane, 1,4- bis(4-aminophenoxy) benzene, 2,2′-bis(4-(4-amino phenoxy)phenyl)propane, 3,3′-diaminodiphenylene sulphone, 4,4′-diaminodiphenylene sulphone, 3,4′-diaminodiphenylene sulphone, or a combination comprising at least one of the foregoing.

### Claim 4 (depends on 1)

The process of claim 1,
wherein the higher monoamine is triethylamine, triethanolamine, tributylamine, dimethyldodecylamine, ammonium hydroxide, triallylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, dibutylamine, dimethylethanolamine, or a combination comprising at least one of the foregoing amines.

### Claim 5 (depends on 1)

The process of claim 1,
wherein the higher monoamine content is greater than 0.3215 mole equivalent per mole equivalent of dianhydride.

### Claim 6 (depends on 1)

The process of claim 1,
wherein an end-capping agent is present during the reacting.

### Claim 7 (depends on 1)

The process of claim 1, wherein the reacting is at a pressure of 0 to 685 kPa.

### Claim 8 (depends on 1)

The process of claim 1, wherein the reacting is in the absence of a halogenated solvent, a solvent having a boiling point greater than 105° C., or both.

### Claim 9 (depends on 1)

The process of claim 1, comprising combining the dianhydride, the water, and the higher monoamine; and then adding the diamine.

### Claim 10 (depends on 1)

The process of claim 1, comprising combining the diamine, the water composition and the higher monoamine; and then adding the dianhydride.

### Claim 11 (depends on 1)

The process of claim 1, comprising combining the higher monoamine with the water; and then adding the dianhydride, or the diamine, or both.

### Claim 12 (depends on 1)

The process of claim 1, wherein the aqueous poly(amic acid) is a homogenous solution.

### Claim 13 (depends on 1)

The process of claim 1, further comprising neutralizing the aqueous poly(amic acid) to precipitate the poly(amic acid).

### Claim 14 (depends on 1)

The process of claim 1, further comprising spray drying the aqueous poly(amic acid) to isolate a poly(amic acid) powder.

### Claim 15 (depends on 1)

A process for producing a polyimide, comprising cyclizing the poly(amic acid) formed by the method of claim 1.

### Claim 16 (depends on 15)

The process of claim 15, wherein the polyimide has at least one of a weight average molecular weight of greater than 10,000 Daltons, a polydispersity index of less than 3.0, or a residual amine content less than 10 ppm.

### Claim 17 (depends on 1)

A process for producing a polyimide coating, comprising
contacting a substrate with the poly(amic acid) aqueous solution of formed by the method of claim 1; and
cyclizing the poly(amic acid) to form the polyimide coating.

### Claim 18 (depends on 17)

The process of claim 17, wherein the substrate is a fiber.