# US 10,308,594 B2 · Curing agents and degradable polymers and composites based thereon

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

- Number: US 10,308,594 B2
- Document ID: US10308594B2
- Status: Granted
- Kind: B2
- Application number: 14/781,242
- Filed: 2014-04-18
- Published: 2016-02-25
- Granted: 2019-06-04
- Earliest claimed: 2013-04-18
- Assignees: Adesso Advanced Materials Wuhu Co., Ltd.
- Applicants: Adesso Advanced Materials Wuxi Co., Ltd.
- Inventors: Bing Qin; Xin Li; Bo Liang
- Web page: https://patentgrep.com/patent/US10308594B2

## CPC

- C07C 243/38: with acylating carboxyl groups bound to carbon atoms of six-membered aromatic rings
- C07C 201/12: by reactions not involving the formation of nitro groups
- C07C 213/02: by reactions involving the formation of amino groups from compounds containing hydroxy groups or etherified or esterified hydroxy groups
- C07C 217/84: the oxygen atom of at least one of the etherified hydroxy groups being further bound to an acyclic carbon atom
- C07C 241/02: Preparation of hydrazines
- C07C 243/28: to hydrogen atoms or to carbon atoms of a saturated carbon skeleton
- C08G 59/1477: {containing nitrogen}
- C08G 59/50: Amines
- C08J 5/243: {using carbon fibres}
- C08J 5/249: {characterised by the additives used in the prepolymer mixture}
- C08J 11/16: by treatment with inorganic material (C08J11/14 takes precedence)
- C08J 11/26: containing carboxylic acid groups, their anhydrides or esters
- C08K 7/06: Elements
- Y02W 30/62: Plastics recycling; Rubber recycling
- C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29)
- C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09)
- Y02W: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT

## Abstract

The present invention provides, among others, compounds of Formula (I) or a salt thereof, methods for making these compounds, degradable polymers and reinforced composites made therefrom, and methods for degrading and/or recycling the degradable polymers and reinforced composites.

## Claims

### Claim 1

A compound of Formula (I) or a salt thereof:
wherein:
each of R1 and R2, independently, is hydrogen, alkyl, cycloalkyl, heterocyclic, heterocycloalkyl, alkenyl, cycloalkenyl, aryl, heteroaryl, alkyl-hetero-alkyl, alkynyl, alkylene, alkylene-hetero-alkylene, alkenylene, alkylene-hetero-alkenylene, alkynylene, or alkylene-hetero-alkynylene; or, R1 and R2, together with the carbon atom to which they are attached, form a 3- to 7-membered saturated or unsaturated cyclic or heterocyclic ring containing 1 to 3 heteroatoms each independently being O, S, or NH;
each of A and B, independently, is alkylene, alkylene-hetero-alkylene, alkenylene, alkenylene-hetero-alkenylene, alkylene-hetero-alkenylene, alkynylene, cycloalkylene, alkylene-cycloalkylene, alkylene-cycloalkylene-alkylene, alkenylene-cycloalkylene, alkenylene cycloalkylene-alkenylene, alkylene-cycloalkylene-alkenylene, alkynylene-cycloalkylene, alkynylene-cycloalkylene-alkynylene, heterocycloalkylene, alkylene-heterocycloalkylene, alkylene-heterocycloalkylene-alkylene, alkenylene-heterocycloalkylene, alkenylene-heterocycloalkylene-alkenylene, alkylene-heterocycloalkylene-alkenylene, alkynylene-heterocycloalkylene, alkynylene-heterocycloalkylene-alkynylene, cycloalkenylene, alkylene-cycloalkenylene, alkylene-cycloalkenylene-alkylene, alkenylene-cycloalkenylene, alkenylene-cycloalkenylene-alkenylene, alkylene-cycloalkenylene-alkenylene, alkynylene-cycloalkenylene, alkynylene-cycloalkenylene-alkynylene, heterocycloalkenylene, alkylene-heterocycloalkenylene, alkylene-heterocycloalkenylene-alkylene, alkenylene-heterocycloalkenylene, alkenylene-heterocycloalkenylene-alkenylene, alkylene-heterocycloalkenylene-alkenylene, alkynylene-heterocycloalkenylene, alkynylene-heterocycloalkenylene-alkynylene, alkylene-arylene, alkylene-arylene-alkylene, alkenylene-arylene, alkenylene-arylene-alkenylene, alkylene-arylene-alkenylene, alkynylene-arylene, alkynylene-arylene-alkynylene, alkylene-hetero-arylene, alkylene-hetero-arylene-alkylene, alkenylene-hetero-arylene, alkenylene-hetero-arylene-alkenylene, alkylene-hetero-arylene-alkenylene, alkynylene-hetero-arylene, or alkynylene-hetero-arylene-alkynylene;
each of R3 and R4, independently, is hydrogen, alkyl, cycloalkyl, heterocyclic, heterocycloalkyl, alkenyl, cycloalkenyl, aryl, heteroaryl, alkoxyalkyl, or alkynyl; and
both m and n are 1.

### Claim 2 (depends on 1)

The compound of claim 1, wherein each of A and B, independently, is alkylene, alkenylene, alkylene-arylene, alkenylene-arylene, alkynylene-arylene, alkylene-hetero-arylene, alkenylene-hetero-arylene, or alkynylene-hetero-arylene.

### Claim 3 (depends on 1)

The compound of claim 1, wherein each of A and B, independently, is alkylene.

### Claim 4 (depends on 3)

The compound of claim 3, wherein both A and B are, at the same time, alkylene.

### Claim 5 (depends on 4)

The compound of claim 4, wherein both A and B are, at the same time, methylene or ethylene.

### Claim 6 (depends on 1)

The compound of claim 1, wherein each of R1 and R2, independently, is hydrogen, alkyl, cycloalkyl, heterocyclic, heterocycloalkyl, alkenyl, cycloalkenyl, aryl, heteroaryl, alkyl-hetero-alkyl, alkynyl, alkylene, alkylene-hetero-alkylene, alkenylene, alkylene-hetero-alkenylene, alkynylene, or alkylene-hetero-alkynylene; or R1 and R2, together with the carbon atom to which they are attached, form a 3- to 7-membered saturated or unsaturated ring.

### Claim 7 (depends on 6)

The compound of claim 6, wherein each of R1 and R2, independently, is hydrogen or alkyl, or R1 and R2, together with the carbon atom to which they are attached, form a 3- to 7-membered saturated ring.

### Claim 8 (depends on 7)

The compound of claim 7, wherein each of R1 and R2, independently, is hydrogen, methyl, or ethyl.

### Claim 9 (depends on 1)

The compound of claim 1, wherein each of R3 and R4, independently, is hydrogen or alkyl.

### Claim 10 (depends on 9)

The compound of claim 9, wherein each of R3 and R4, independently, is hydrogen, methyl, ethyl, propyl, or isopropyl.

### Claim 11 (depends on 1)

The compound of claim 1, wherein the compound is

### Claim 12 (depends on 1)

The compound of claim 1, wherein the compound is a salt formed with an organic acid or Lewis acid.

### Claim 13 (depends on 12)

The compound of claim 12, wherein organic acid is a C1-10 aliphatic, cycloaliphatic, aromatic, or heteroaromatic carboxylic acid.

### Claim 14 (depends on 12)

The compound of claim 12, wherein the compound is a salt of oxalic acid, citric acid, or zinc chloride.

### Claim 15 (depends on 1)

A degradable cross-linked polymer, wherein the polymer is synthesized by curing an epoxy resin with a compound of claim 1, the epoxy resin comprises a glycidyl ether epoxy resin, glycidyl ester epoxy resin, glycidyl amine epoxy resin, trifunctional epoxy resin, tetrafunctional epoxy resin, novolac epoxy resin, cresol-novolac epoxy resin, aliphatic epoxy resin, alicyclic epoxy resin, or nitrogen-containing epoxy resin.

### Claim 16 (depends on 15)

A method for degrading degradable cross-linked polymer of claim 15, comprising the steps of:
(1) under the condition of heating and stirring, the cross-linked polymer is immersed in a mixture comprising an acid and a solvent, the mixture is heated to a temperature in the range of 15-400° C., the heating time is 1-120 hours, and the mass concentration of acid in the solvent is 0.1-100%;
(2) using an alkaline solution of 0-200° C. to adjust the pH value of the mixture of acid and solvent to at least 6, the mass concentration of alkali solution is 0.1-100%.

### Claim 17 (depends on 16)

The method of claim 16, wherein the acid comprises hydrochloric acid, hydrobromic acid, hydrofluoric acid, acetic acid, trifluoroacetic acid, lactic acid, formic acid, propionic acid, citric acid, methanesulfonic acid, p-toluenesulfonic acid, nitric acid, sulfuric acid, sulfurous acid, phosphoric acid, perchloric acid, benzoic acid, salicylic acid, or phthalic acid; and the solvent comprises methanol, ethanol, ethylene glycol, propanol, isopropanol, butanol, isobutanol, t-butanol, pentanol, hexanol, heptanol, octanol, nonanol, benzyl alcohol, phenethyl alcohol, p-hydroxymethyl benzene, m-hydroxymethyl benzene, o-hydroxy benzene, p-hydroxyethyl benzene, m-hydroxyethyl benzene, o-hydroxyethyl benzene, water, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, tetrahydrofuran, methyl tetrahydrofuran, glycerol, or dioxane; the alkali comprises lithium hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, ammonia; the alkali solvent comprises methanol, ethanol, ethylene glycol, propanol, isopropanol, butanol, isobutanol, t-butanol, pentanol, hexanol, heptanol, octanol, nonanol, water, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, tetrahydrofuran, methyl tetrahydrofuran, glycerol, or dioxane.

### Claim 18 (depends on 17)

The method of claim 17, wherein in step (1), the heating temperature is 80-150° C., heating time is 4-8 hours, and the mass concentration of acid in the solvent is 0.5-20%; in step (2) the temperature is 5-50° C., the pH value is adjusted to the range of 6-12, the concentration of alkali solution is 5-30%.

### Claim 19 (depends on 1)

A prepreg material or a reinforced composite material, wherein the material is derived from a compound of claim 1, an epoxy resin, an optional auxiliary material, and a reinforcing material; the epoxy resin comprises a glycidyl ether epoxy resin, glycidyl ester epoxy resins, glycidyl amine epoxy resin, trifunctional epoxy resin, tetrafunctional epoxy resin, novolac epoxy resin, o-cresol novolac epoxy resin, aliphatic epoxy resin, alicyclic epoxy resin, or nitrogen-containing epoxy resin; the reinforcing material comprise carbon nanotubes, boron nitride nanotubes, carbon black, metal nano-particles, metal oxide nanoparticles, organic nanoparticles, iron oxide, glass fibers, carbon fibers, natural fibers, synthetic fibers, or a fabric made up by fiber material; and the optional auxiliary material comprise an accelerator, diluent, plasticizer, toughening agent, thickening agent, coupling agent, defoamer, flatting agent, ultraviolet absorber, antioxidant, brightener, fluorescent agent, pigment, or filler.

### Claim 20 (depends on 1)

A method for preparing a compound of Formula (I) of claim 1, wherein both R3 and R4 are hydrogen, comprising the following reaction scheme:
A, B, R1, and R2 are as defined in claim 1,
each X independently is a halogen atom, or both X groups together form ═O;
each of Raa and Rbb, independently, is alkyl, cycloalkyl, heterocycle, heterocycloalkyl, alkenyl, cycloalkenyl, aryl, heteroaryl, alkyl-hetero-alkyl, or alkynyl;
each of Ra and Rb, independently, is hydrogen, alkali metal, alkaline earth metal, or quaternary ammonium salt;
when each X independently is a halogen atom, intermediate compound 4′ reacts with hydrazine in a second organic solvent at a temperature in the range of 0-150° C. to produce compound 5′; and
when both X groups together form ═O, intermediate compound 4′ reacts with hydrazine in a second organic solvent at a temperature in the range of 0-150° C. to produce compound 5′.

### Claim 21 (depends on 20)

The method of claim 20, wherein the second organic solvent comprises methanol, ethanol, propanol, isopropanol, butanol, isobutanol, t-butanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol, dioxane, tetrahydrofuran, or ethylene glycol; and the hydrazine comprises anhydrous hydrazine or hydrazine hydrate.

### Claim 22 (depends on 20)

The method of claim 20, wherein each X independently is a halogen atom, compounds 1′, 2′, and 3′ react in a first organic solvent at a temperature in the range of 30-200° C. to produce intermediate 4′, the molar ratio of compounds 1′ and 2′ is not higher than 10:1, and the molar ratio of the compounds 1′ and 2′ versus compound 3′ is not higher than 100:1.

### Claim 23 (depends on 22)

The method of claim 22, wherein the first solvent comprises tetrahydrofuran or dioxane.

### Claim 24 (depends on 20)

The method of claim 20, wherein both X groups together form ═O, and both Ra and Rb are hydrogen.

### Claim 25 (depends on 24)

The method of claim 24, wherein compounds 1′, 2′, and 3′ react in a first organic solvent in the presence of a catalyst at a temperature in the range of 30-200° C. to produce intermediate 4′, the molar ratio of compounds 1′ and 2′ is not higher than 10:1, and the molar ratio of the compounds 1′ and 2′ versus compound 3′ is not higher than 100:1.

### Claim 26 (depends on 25)

The method of claim 25, wherein the catalyst comprises p-toluenesulfonic acid, pyridinium p-toluenesulfonic acid, sulfuric acid, phosphoric acid, nitric acid, hydrogen chloride, molecular sieves, sulfonic acid resin, or solid super acid.