阅读说明：本技术 一种基于氨基酸型固化剂的单组分环氧树脂 (Single-component epoxy resin based on amino acid type curing agent ) 是由 马松琪 于震 汤兆宾 刘艳林 朱锦 于 2021-07-19 设计创作，主要内容包括：本发明公开了一种基于氨基酸型固化剂的单组分环氧树脂,包括下述质量份数的组分：缩水甘油酯型环氧树脂100份、氨基酸型固化剂10～140份。本发明还公开了上述单组分环氧树脂的制备方法。氨基酸酸型固化剂来源广泛,氨基酸在分子结构中同时存在氨基和羧基,使其中氨基的活性大大降低,与环氧树脂混合后组成的单组分环氧树脂储存期、适用期大大增长。温度升高后,固化剂中的氨基和羧基均会和环氧基团迅速反应形成三维交联网络结构。由于其潜伏特性,氨基酸与环氧树脂配合后组成的单组分环氧树脂可应用于单组分胶黏剂、涂料、密封剂和树脂基纤维复合材料中预浸料的制备等方面。(The invention discloses a single-component epoxy resin based on an amino acid type curing agent, which comprises the following components in parts by mass: 100 parts of glycidyl ester type epoxy resin and 10-140 parts of amino acid type curing agent. The invention also discloses a preparation method of the single-component epoxy resin. The amino acid type curing agent has wide sources, and amino groups and carboxyl groups exist in the molecular structure of amino acid, so that the activity of the amino groups is greatly reduced, and the storage life and the pot life of the single-component epoxy resin formed by mixing the amino acid type curing agent with the epoxy resin are greatly prolonged. After the temperature is raised, both amino and carboxyl in the curing agent can rapidly react with epoxy groups to form a three-dimensional cross-linked network structure. Due to the latent characteristic, the monocomponent epoxy resin formed by matching amino acid and epoxy resin can be applied to the preparation of a monocomponent adhesive, a coating, a sealant, a prepreg in a resin-based fiber composite material and the like.)

1. The single-component epoxy resin based on the amino acid type curing agent is characterized by comprising the following components in parts by mass:

2. the one-component epoxy resin based on an amino acid type curing agent according to claim 1, characterized by comprising the following components in parts by mass:

3. the one-component epoxy resin based on an amino acid type curing agent according to claim 1 or 2, wherein the amino acid type curing agent has a structure as shown in (I):

H₂N-R-COOH (I)

wherein R is: -CH₂-*、-(CH₂)₁₀-*、-(CH₂)₁₁-*、

Any one or more of the structural formulas;

in the structural formula of R, the x represents a chemical bond connected with COOH.

4. The one-component epoxy resin based on an amino acid type curing agent according to claim 1 or 2, wherein the epoxy resin is any one or a combination of bisphenol a type epoxy resin, bisphenol F type epoxy resin, novolac type epoxy resin, and glycidyl ester type epoxy resin.

5. The one-component epoxy resin based on an amino acid type curing agent according to claim 1 or 2, wherein the accelerator is one or a combination of several of tertiary amine and its salt, acetylacetone metal salt, adduct of aryl isocyanate, triphenylphosphine and its phosphonium salt, peroxide, lewis acid, organic carboxylate and its complex, quaternary ammonium salt and DBU organic salt.

6. The one-pack epoxy resin based on an amino acid type curing agent according to claim 5, wherein the accelerator is 2,4, 6-tris (dimethylaminomethyl) phenol, tris (2-ethylhexanoate) salt of 2,4, 6-tris (dimethylaminomethyl) phenol, trioleate of 2,4, 6-tris (dimethylaminomethyl) phenol, triethylamine, o-hydroxybenzyldimethylamine, N- (2-hydroxyphenyl) -N ', N' -dimethylurea, N- (2-hydroxy-4-nitrophenyl) -N ', N' -dimethylurea, benzoyl peroxide, chromium naphthenate-diethylenetriamine, chromium naphthenate-N-methylethanolamine, manganese octanoate-diethylenetriamine, manganese octanoate-N-methylethanolamine, manganese octanoate-diethylenetriamine, Any one or a combination of more of 2-phenylimidazoline, N-diglycidyl aniline and 2-methylimidazole.

7. The one-component epoxy resin based on amino acid type curing agent according to claim 1 or 2, wherein the epoxy reactive diluent is any one or a combination of 1, 2-epoxybutane, N-glycidyl diethylamine, butyl glycidyl ether, glycidyl acrylate, glycidyl oleate, and glycidyl benzoate.

8. The process for the preparation of one-component epoxy resins based on amino acid type curing agents according to any of claims 1 to 7, characterized in that the following components are added in parts by mass:

and adding 0-500 parts of solvent, heating, stirring and mixing, and vacuumizing to evaporate the solvent to obtain the single-component epoxy resin.

9. The method for preparing one-component epoxy resin based on amino acid type curing agent according to claim 8, wherein the solvent is one or more of water, alcohols, ethers and ketones.

10. The preparation method of the amino acid type curing agent-based single-component epoxy resin according to claim 8, wherein the temperature is raised to 50-100 ℃, and the mixture is stirred for 1-12 hours; the temperature for vacuum-pumping and evaporating the solvent is 50-100 ℃.

Technical Field

The invention belongs to the field of polymers, and particularly relates to an amino acid type latent epoxy resin curing agent and a single-component epoxy resin.

Background

The epoxy resin prepolymer is of a linear structure, and needs to be subjected to curing reaction with a curing agent to form a three-dimensional cross-linked network structure, so that the epoxy resin with excellent thermal/mechanical properties and solvent resistance can be obtained. When the epoxy resin is used in a large composite material system, the resin needs to have certain fluidity before curing, even the curing reaction does not occur at medium and low temperature, and when the temperature is increased, the curing reaction occurs between the curing agent and the epoxy resin.

Most of the current latent epoxy resin curing agents come from fossil resources, and mainly comprise dicyandiamide, ketimine, organic acid anhydride, organic hydrazide and the like.

CN110128376A discloses a latent epoxy hardener, which is obtained by reacting sulfinyl acetic acid, aromatic secondary amine and diepoxide, has a long pot life when being matched with epoxy resin, and the sulfinyl in the epoxy hardener can generate a Pummerer rearrangement reaction when the temperature is raised to form mercaptan which can be rapidly crosslinked with the epoxy resin under the catalysis of tertiary amine groups; the latent epoxy curing agent is complicated to prepare and difficult to refine.

CN101885832A discloses a preparation method of a novel latent nonionic self-emulsifying epoxy curing agent, which utilizes long alkyl chain fatty amine to react with diglycidyl ether to prepare an addition product with a long hydrophobic side chain connected in the middle and epoxy groups at two ends; then polyamine and carbonyl compound are reacted to prepare imine compound containing secondary amine in the middle for blocking, thus preparing the latent nonionic self-emulsifying epoxy curing agent; the preparation process is long and the reaction control difficulty is high.

Amino acid is a small molecule which forms protein in nature, has wide source and is easy to obtain; the formation of the inner salt makes it often poorly compatible with most organic solvents, which also means that it has the potential to be used as a latent epoxy resin curing agent.

Disclosure of Invention

The invention aims to provide the single-component epoxy resin based on the amino acid type curing agent, the source of the amino acid type curing agent is wide, and the single-component epoxy resin based on the amino acid type curing agent has a long storage life.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

the single-component epoxy resin based on the amino acid type curing agent comprises the following components in parts by mass:

preferably, the one-component epoxy resin based on the amino acid type curing agent comprises the following components in parts by mass:

under the preferable scheme, the dilution effect and the curing acceleration effect are good.

Preferably, the amino acid type curing agent has a structure shown in (I):

H₂N-R-COOH (I)

wherein R may be: -CH₂-*、-(CH₂)₁₀-*、-(CH₂)₁₁-*、

Any one or more of the structural formulas;

in the structural formula of R, the x represents a chemical bond connected with COOH.

Amino acid has both amino and carboxyl in the molecular structure, so that the activity of the amino group is greatly reduced, the amino acid has an intramolecular salt structure, so that the amino acid is often poor in compatibility with most organic solvents, and the single-component epoxy resin prepared by blending the amino acid with the epoxy resin at room temperature has good storage stability; when the temperature is increased, both the amino group and the carboxyl group in the amino acid and the epoxy group in the epoxy resin can be subjected to curing reaction to form a three-dimensional cross-linked network structure, which means that the amino acid has the potential of serving as a latent epoxy resin curing agent.

Preferably, the epoxy resin is any one or combination of bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenolic aldehyde type epoxy resin and glycidyl ester type epoxy resin, and the epoxy resins are commercially commonly used epoxy resins and are easily obtained.

Preferably, the accelerator may be tertiary amine and its salt, acetylacetone metal salt, adduct of aryl isocyanate, triphenylphosphine and its phosphonium salt, peroxide, lewis acid, organic carboxylate and its complex, quaternary ammonium salt and DBU organic salt, and the like. Since the curing reaction activity of the amino acid and the epoxy resin is low, an accelerator may be added to promote the reaction.

More preferably, the accelerator may be 2,4, 6-tris (dimethylaminomethyl) phenol, tris (2-ethylhexanoate) salt of 2,4, 6-tris (dimethylaminomethyl) phenol, trioleate salt of 2,4, 6-tris (dimethylaminomethyl) phenol, triethylamine, o-hydroxybenzyldimethylamine, N- (2-hydroxyphenyl) -N ', N ' -dimethylurea, N- (2-hydroxy-4-nitrophenyl) -N ', N ' -dimethylurea, benzoyl peroxide, chromium naphthenate-diethylenetriamine, chromium naphthenate-N-methylethanolamine, manganese octanoate-diethylenetriamine, manganese octanoate-N-methylethanolamine, 2-phenylimidazoline, N-diglycidylaniline, N-di (dimethylaminomethyl) aniline, tri (2-ethyl hexanoate) salt of 2,4, 6-tris (dimethylaminomethyl) phenol, tri (ethyl-methyl-amine, o-hydroxybenzyldimethylamine, N- (2-hydroxyphenyl) -N ', N ' -dimethylurea, N- (2-hydroxy-4-nitrobenzene-N ' -dimethylurea, benzoyl peroxide, chromium naphthenate-diethylenetriamine, chromium naphthenate-N-methylethanolamine, manganese naphthenate-N-methylethanolamine, 2-phenylimidazoline, N-diglycidylaniline, N-methylethanolamine, N-dimethylolaniline, N-methylethanolamine, p-methylethanolamine, N-methylethanolamine, p-N-methylethanolamine, p-N-methylethanolamine, p-N-methylethanolamine, p-N-methylethanolamine, p-methyl, Any one or combination of several of 2-methylimidazole. These accelerators can play a role in accelerating the curing reaction with high efficiency.

Preferably, the epoxy reactive diluent is any one or a combination of more of 1, 2-epoxybutane, N-glycidyl diethylamine, butyl glycidyl ether, glycidyl acrylate, glycidyl oleate and glycidyl benzoate.

The epoxy reactive diluent is adopted, so that the viscosity of the system of the composition is reduced in the forming process, and the composition has better wetting power and penetrability.

The epoxy resin has excellent comprehensive performance, and particularly has wide application as a resin-based composite material in daily life and aerospace industry. The amino acid type latent epoxy resin curing agent has good storage stability after being mixed with epoxy resin, so the mixture can be used as a single-component adhesive, a coating, a sealant and a prepreg in a resin-based fiber composite material, is widely applied to the fields of buildings, machinery, electronics, electricity, aerospace and the like, and has the advantages of simplifying the production process, preventing environmental pollution, improving the product quality, adapting to modern large-scale industrial production and the like.

The invention also provides a preparation method of the single-component epoxy resin based on the amino acid type curing agent, which has the advantages of simple preparation process, easy operation, little pollution and stable quality.

A preparation method of single-component epoxy resin based on amino acid type curing agent comprises the following components in parts by mass:

and adding 0-500 parts of solvent, heating, stirring and mixing, and vacuumizing to evaporate the solvent to obtain the single-component epoxy resin.

Preferably, the solvent is one or a combination of water, alcohols, ethers and ketones. Preferably one or more of water, C1-C8 monohydric alcohol, tetrahydrofuran and acetone. Such solvents may increase the solubility of the amino acid in the epoxy resin.

Heating to 50-100 ℃, and stirring for 1-12 h; the temperature for vacuum-pumping and evaporating the solvent is 50-100 ℃.

The preparation method can synthesize different amino acids through structural design, so that the thermodynamic property of the finally obtained epoxy resin can be adjusted, the tensile strength can be increased from 30MPa to 120MPa, and the glass transition temperature can be increased from 40 ℃ to 90 ℃.

Compared with the prior art, the invention has the following advantages:

1) the raw materials adopt amino acid type curing agents, have wide sources, can be directly obtained from the nature, and can also be synthesized by a chemical method.

2) The single-component epoxy resin system is prepared by utilizing the characteristic of low reaction activity of amino acid and the epoxy resin system, and has longer storage period; the single-component epoxy resin can be applied to single-component adhesives, coatings, sealants and the like.

3) The single-component epoxy resin system has good fluidity at the molding temperature, facilitates the resin to soak the fiber, and meets the requirements of the preparation and molding process of the prepreg in the resin-based fiber composite material.

4) The single-component epoxy resin provided by the invention has the advantages of simple preparation process, easiness in operation, small pollution and stable quality, and is suitable for a modern industrial large-scale production mode.

Drawings

FIG. 1 is a nuclear magnetic hydrogen spectrum of PDA-MAH prepared in preparation example 1.

FIG. 2 is a digital photograph of the one-component epoxy resin of example 1 from day 1 to day 22, taken on a regular basis after the vials were placed horizontally 180 ℃ for 5 seconds.

Detailed Description

The invention is further illustrated by the following examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

Preparation example 1 preparation of amino acid type curing agent I-1

Dissolving 1g of pentamethylene diamine and 1g of maleic anhydride by using 10mL of dichloromethane, reacting at 30 ℃ for 2 hours, pouring out the dichloromethane, adding 10mL of absolute ethyl alcohol, continuing to react at 30 ℃ for 2 hours, recrystallizing at 0 ℃ for 2 hours, cold suction filtering, repeating recrystallization and cold suction filtering for 2-3 times to obtain the PDA-MAH amino acid type curing agent I-1, wherein the structural formula is as follows:

the PDA-MAH nuclear magnetic hydrogen spectrum is shown in figure 1.

Example 1

Mixing 2g of glycidyl methylenesuccinate and 1g of amino acid type curing agent I-1, adding 2g of ethanol and 2g of water, adding 0.05g of 2,4, 6-tris (dimethylaminomethyl) phenol, heating to 80 ℃, stirring for 2h, and removing the solvent in the system for 1h by using a vacuum oven at 80 ℃ to obtain the single-component epoxy resin.

Photographs of the state of the system from day 1 to day 22 of the one-component epoxy resin were recorded, and the storage life of the one-component epoxy resin was 22 days as shown in fig. 2.

Heating to 100 ℃ for curing reaction, and then post-curing in a vacuum oven at 180 ℃ to obtain the cured epoxy resin. The cured epoxy resin has tensile strength of 120MPa, tensile modulus of 2000MPa, elongation at break of 8% and glass transition temperature of 94 ℃.

Example 2

2g of American Dow bisphenol F type liquid epoxy resin DER354, 2.8g of 11-aminoundecanoic acid and 0.6g of butyl glycidyl ether are mixed, 8g of acetone is added, the temperature is raised to 60 ℃, the mixture is stirred for 12 hours, a vacuum oven is used for removing the solvent in the system for 0.5 hour at 70 ℃, and the single-component epoxy resin is obtained, wherein the storage period is 20 days.

Heating to 120 ℃ for curing reaction, and then performing post curing in a vacuum oven at 180 ℃ to obtain the cured epoxy resin. The tensile strength of the cured epoxy resin is 40MPa, the tensile modulus is 120MPa, the elongation at break is 30 percent, and the glass transition temperature is 45 ℃.

Example 3

Mixing 2g of epoxy resin CYDPN-048 of the company Batin petrochemical industry, 0.5g of serine and 0.1g of glycidyl oleate, adding 1g of diethyl ether, heating to 50 ℃, stirring for 8 hours, and removing the solvent in the system for 0.5 hour at 60 ℃ by using a vacuum oven to obtain the single-component epoxy resin.

Heating to 140 ℃ for curing reaction, and then performing post curing in a vacuum oven at 180 ℃ to obtain the cured epoxy resin.

Example 4

2g of Dow DER331, 0.2g of glycine, 0.1g of 2-methylimidazole and 0.1g of manganese octoate-N-methylethanolamine are mixed, 2g of water is added, the temperature is raised to 100 ℃, the mixture is stirred for 1 hour, and the solvent in the system is pumped out for 2 hours at 100 ℃ by using a vacuum oven to obtain the single-component epoxy resin.

Heating to 160 ℃ for curing reaction, and then performing post curing in a vacuum oven at 180 ℃ to obtain the cured epoxy resin.

Example 5

2g of phenolic epoxy resin CYDPN-048, 1.5g of 10-aminodecanoic acid and 0.01g of N- (2-hydroxyphenyl) -N ', N' -dimethylurea, which are produced by the company of Baling petrochemical company Limited, are mixed, heated to 90 ℃, and stirred for 4 hours to obtain the single-component epoxy resin.

Heating to 140 ℃ for curing reaction, and then performing post curing in a vacuum oven at 180 ℃ to obtain the cured epoxy resin.

Example 6

2g of Dow DER332, 1g of aspartic acid, 0.02g of chromium naphthenate-diethylenetriamine and 0.4g of glycidyl benzoate are mixed, 5g of tetrahydrofuran and 5g of water are added, the temperature is raised to 100 ℃, stirring is carried out for 8 hours, and the solvent in the system is pumped out for 2 hours at 100 ℃ by a vacuum oven to obtain the single-component epoxy resin.

Heating to 150 ℃ for curing reaction, and then performing post curing in a vacuum oven at 180 ℃ to obtain the cured epoxy resin.

Example 7

Mixing 2g of epoxy resin E-44 of the company of Baling petrochemical industry, 1g of cysteine, 1g of glycine, 0.08g of boron trifluoride, 0.2g of glycidyl benzoate and 0.2g of glycidyl acrylate, adding 5g of n-octanol, heating to 100 ℃, stirring for 8 hours, and removing the solvent in the system for 2 hours by using a vacuum oven at 100 ℃ to obtain the single-component epoxy resin.

Heating to 150 ℃ for curing reaction, and then performing post curing in a vacuum oven at 180 ℃ to obtain the cured epoxy resin.