CN110669463A

CN110669463A - Epoxy resin adhesive and application thereof

Info

Publication number: CN110669463A
Application number: CN201810718899.9A
Authority: CN
Inventors: 杜美娜
Original assignee: Beijing Tianshan New Material Technology Co Ltd
Current assignee: Beijing Tianshan New Material Technology Co Ltd
Priority date: 2018-07-03
Filing date: 2018-07-03
Publication date: 2020-01-10

Abstract

The invention provides an epoxy resin adhesive and application thereof. The adhesive comprises epoxy resin, a curing agent and an antiallergic agent, wherein the antiallergic agent has a structure shown in a formula I and/or a formula II. The anti-allergic agent can effectively capture small molecules. During the curing process, the curing agent micromolecules can be effectively captured, and the release is reduced, so that the possibility of allergy and smell of operators are reduced. Meanwhile, the anti-sensitivity agent has no adverse effect on the product performance of the epoxy resin adhesive, and the product is different from the traditional anti-sensitivity agent and odor masking agent, and cannot cause harm to human bodies.

Description

Epoxy resin adhesive and application thereof

Technical Field

The invention relates to the field of epoxy resin adhesives, in particular to an epoxy resin adhesive and application thereof.

Background

The epoxy resin adhesive has high bonding strength and excellent performance, is a very important adhesive, has various brands so far and is widely used in various industries. The epoxy resin adhesive product comprises a two-component epoxy resin adhesive product which is respectively packaged by a substrate and a curing agent and a one-component epoxy resin adhesive product which is packaged by a component after each component is prepared, and the latter is also called a one-component epoxy resin adhesive. The curing of the epoxy resin adhesive mainly depends on an epoxy curing agent, the types of common curing agents in the market at present are mainly amines, acid anhydrides and imidazoles, wherein the amine curing agents are various and have wider adaptability relative to other types and are the most common curing agents, but the amine curing agents contain a plurality of small molecular amine substances, so that the amine curing agents are easy to sensitize in the using process, even some substances can cause cancer, most amines have larger odor, people feel uncomfortable in the using process, the released small molecular substances can pollute the environment, and the use of the epoxy resin adhesive is limited to a certain extent.

Disclosure of Invention

The invention mainly aims to provide an epoxy resin adhesive, which solves the problems that in the using process of the adhesive, small molecular substances are released to cause allergy and odor of users.

In order to achieve the above object, according to one aspect of the present invention, there is provided an epoxy resin adhesive specifically comprising an epoxy resin and a curing agent, and further comprising a desensitizer having a structure represented by formula I and/or formula II:

wherein R is₁And R₂Each independently selected from alkyl, halogen, sulfonic acid, alicyclic group, phenyl, hydroxyl, alcyl, -R- (COO) -R, -R-COOH, R- (CO) -, R (COO) -or soy-based₃Selected from alkyl sulfate anions.

Further, the alkyl is a linear or branched alkyl of C1-C12, preferably methyl, ethyl or propyl; the alicyclic group is a substituted or unsubstituted alicyclic group of C3-C12, and is preferably cyclohexane or methylcyclohexane; the alcohol alkyl is C1-C12 straight chain or branched chain alcohol alkyl, preferably hydroxyethyl, hydroxypropyl or hydroxybutyl; r is independently selected from alkyl or alkylene groups of 1 to 12 carbons, preferably 2 to 4 carbons, which may be substituted or unsubstituted.

Further, the anti-allergic agent is 4-ethyl-4-soyabean ethyl sulfate morpholine.

Furthermore, the weight ratio of the epoxy resin, the curing agent and the anti-allergic agent is 20-115: 2-7: 0.1-2.

Furthermore, the epoxy resin adhesive also comprises a pre-gelling auxiliary agent, and preferably, the pre-gelling auxiliary agent is acrylic polymer particles and/or acrylic core-shell particles.

Further, the weight ratio of the pre-gelling auxiliary agent to the epoxy resin is 3-18: 20-115.

Further, the epoxy resin adhesive also comprises a toughening agent, wherein the toughening agent is preferably a core-shell rubber toughening agent and/or a CTBN toughening agent, and the weight ratio of the core-shell rubber toughening agent to the CTBN toughening agent is more preferably 3: 1-1: 5.

Further, the weight ratio of the toughening agent to the epoxy resin is 8-30: 20-115.

Further, the epoxy resin is one or more of liquid epoxy resin, solid epoxy resin and semi-solid epoxy resin, and the curing agent is an amine curing agent.

Further, the liquid epoxy resin comprises bisphenol A type liquid epoxy resin and/or bisphenol F type liquid epoxy resin, preferably, the epoxy resin comprises liquid epoxy resin and semi-solid epoxy resin, and the semi-solid epoxy resin accounts for 1-50% of the total weight of the epoxy resin.

According to another aspect of the invention, the application of the epoxy resin adhesive in the field of motor magnetic steel sheet adhesion is also provided.

The anti-sensitivity agent with the structure shown in the formula I and/or the formula II is added into the epoxy resin adhesive provided by the invention, and the anti-sensitivity agent can effectively capture small molecules. During the curing process, the curing agent micromolecules can be effectively captured, and the release is reduced, so that the possibility of allergy and smell of operators are reduced. Meanwhile, the anti-sensitivity agent has no adverse effect on the product performance of the epoxy resin adhesive, and the product is different from the traditional anti-sensitivity agent and odor masking agent, and cannot cause harm to human bodies.

C1-C12 mean that the carbon number is 1-12, and C3-C12 mean that the carbon number is 3-12.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 shows the temperature change curves of the viscosity of the epoxy resin adhesives provided in examples 9 and 14 of the present invention.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

The present application is described in further detail below with reference to specific examples, which should not be construed as limiting the scope of the invention as claimed.

As described in the background section, the epoxy adhesives of the prior art are prone to cause problems of allergy and odor to the user due to the release of small molecules during the use.

In order to solve the problem, the invention provides an epoxy resin adhesive, which specifically comprises an epoxy resin and a curing agent, and the epoxy resin adhesive also comprises a sensitivity inhibitor, wherein the sensitivity inhibitor has a structure shown in a formula I and/or a formula II:

The anti-allergic agent can effectively capture small molecules. During the curing process, the curing agent micromolecules can be effectively captured, and the release is reduced, so that the possibility of allergy and smell of operators are reduced. Meanwhile, the anti-sensitivity agent has no adverse effect on the product performance of the epoxy resin adhesive, and the product is different from the traditional anti-sensitivity agent and odor masking agent, and cannot cause harm to human bodies.

In a preferred embodiment, the alkyl is a linear or branched alkyl of C1 to C12, preferably methyl, ethyl or propyl; the alicyclic group is a substituted or unsubstituted alicyclic group of C3-C12, and is preferably cyclohexane or methylcyclohexane; the alcohol alkyl is C1-C12 straight chain or branched chain alcohol alkyl, preferably hydroxyethyl, hydroxypropyl or hydroxybutyl; r is independently selected from the group consisting of branched or straight chain alkyl or alkylene groups of 1 to 12 carbons, preferably 2 to 4 carbons, which may be substituted or unsubstituted. Besides the better ability of capturing small molecules, the anti-allergic agent has the advantages of relatively simple preparation process and relatively low cost.

In order to further improve the small molecule capture capacity of the anti-allergy agent, in a preferred embodiment, the anti-allergy agent is 4-ethyl-4-soyabean ethyl sulfate morpholine.

In order to further improve the performance of the epoxy resin adhesive in all aspects, in a preferred embodiment, the weight ratio of the epoxy resin, the curing agent and the anti-sensitivity agent is 20-115: 2-7: 0.1-2.

In addition to the above-mentioned problem of releasing allergy-inducing small molecules, most epoxy adhesives suffer from the following problems: because some epoxy resin adhesives need to be heated and cured in the using process, the viscosity of the glue is reduced along with the rise of the temperature in the heating process, so that the glue flows everywhere, the problems of collapse, flowing and the like occur, the environment and products are polluted, the products are poor, and the cleaning and reworking cost is increased. For example, in the production and manufacture of servo motors, an important link is the adhesion of magnetic steel sheets of the motors, and due to the high working temperature, single-component epoxy with high temperature resistance is usually selected for adhesion. In the bonding process, the viscosity of the glue is greatly reduced along with the increase of the heating temperature; the glue is then gradually cured as the heating temperature is increased further to the curing temperature. In the traditional single-component epoxy glue, in the process that the heating temperature is increased and the curing temperature is not reached, the phenomenon that glue water is empty due to the fact that the viscosity of the glue is sharply reduced can occur due to the sharp reduction of the viscosity of the glue, so that defects and defects in production and manufacturing are caused, and due to the existence of a heating link, the release of small molecular substances in the glue can be further accelerated, and the risk of sensitization and carcinogenesis is increased.

In order to further ameliorate the above problem, in a preferred embodiment, the epoxy adhesive further comprises a pre-gelling aid. The addition of the pre-gelling auxiliary agent can ensure that the viscosity of the glue does not sharply decrease but increases in the process that the glue does not reach the curing temperature with the increase of the heating temperature, and the original shape can be continuously maintained until the temperature reaches the curing temperature, and the glue is gradually cured. The pre-gelling performance can effectively avoid the defects of flowing and the like caused by that the glue can flow randomly along with the reduction of viscosity in the temperature rising process, and meanwhile, the pre-gelling performance is greatly helpful for improving the mechanical strength, the bonding strength and the like of the product. Preferably, the pre-gelling aid is acrylic polymer particles and/or acrylic core-shell particles.

In order to further improve the performance of the epoxy resin adhesive in all aspects, in a preferred embodiment, the weight ratio of the pre-gelling auxiliary agent to the epoxy resin is 3-18: 20-115. Under the action of the pre-gelling auxiliary agent, when the heating temperature of the epoxy resin adhesive is more than or equal to 70 ℃, the viscosity of the system is gradually increased until the epoxy resin adhesive is cured. More preferably, the pre-gelling aids include, but are not limited to, one or more of ZEFIAC F351, ZEFIAC F340M, ZEFIAC F325, ZEFIAC F320, ZEFIAC F301, ZEFIAC F303, STAPHYLOID AC-3355, and STAPHYLOID AC 4030.

In a preferred embodiment, the epoxy adhesive further comprises a toughening agent. The toughening agent is added, so that the toughness, the impact resistance, the thermal shock resistance and the tear resistance of the adhesive are improved. The toughening agent is preferably a core-shell rubber toughening agent and/or a CTBN toughening agent, and the weight ratio of the core-shell rubber toughening agent to the CTBN toughening agent is more preferably 3: 1-1: 5. The mixture of the two toughening agents and the core-shell rubber toughening agent are used, so that a system obtains a high-degree phase separation, a shell structure plays a role in protecting compatibility of a core and an epoxy matrix, the CTBN toughening agent can enable the system to generate a certain phase separation, the toughness, the impact resistance, the thermal shock property and the tear strength of epoxy are improved, the bonding performance of the adhesive can be improved, the mixture of the CTBN toughening agent and the epoxy matrix can enable the CTBN toughening agent and the CTBN toughening agent to generate a synergistic effect, and the comprehensive performance of the adhesive is further improved.

Preferably, the core shell rubber based toughener includes, but is not limited to, the MBS core shell rubbers of Kane Ace, such as B564, B561, B56, M511, M521, M701, M711, M732, M300, MX125, MX154, MX267, and the CTBN tougheners include, but are not limited to, Hypotm CTBN1300x 8F, Hypotm CTB 2000x162, Hypotm CTBN1300x31, Hypotm CTBN1300x 13F, Hypotm CTBNX1300x 9, Hypotm CTBNX1300x18, Dielda 86840, and 861340.

In order to further balance the comprehensive performance of the adhesive, in a preferred embodiment, the weight ratio of the toughening agent to the epoxy resin is 8-30: 20-115.

The epoxy resin in the above adhesive may be of a type commonly used in the art. In a preferred embodiment, the epoxy resin is one or more of liquid epoxy resin, solid epoxy resin and semi-solid epoxy resin, the liquid epoxy resin includes bisphenol a type liquid epoxy resin and/or bisphenol F type liquid epoxy resin, preferably, the epoxy resin includes liquid epoxy resin and semi-solid epoxy resin, and the semi-solid epoxy resin accounts for 1-50% of the total weight of the epoxy resin. The semi-solid epoxy resin is non-flowable epoxy resin with viscoelasticity at normal temperature, such as NPEL-134 and E-39D. The weight ratio of bisphenol A epoxy resin to bisphenol F epoxy resin to semi-solid epoxy resin is 20-65: 1-25, and the combination of the three resins can increase the bonding strength, control the crosslinking density, well control the viscosity of the system and optimize the comprehensive performance of the formula.

The curing agent is not particularly limited as long as it can cause a curing reaction with the epoxy resin, and is preferably an amine-based curing agent, including, but not limited to, ethylenediamine, diethylenediamine, diethylenetriamine, triethylenetetramine, propylenediamine, tetraethylenepentamine, hexaethyleneheptamine, hexamethylenediamine, 2-methyl-1, 5-pentylenediamine, aminoethylpiperazine, 4, 7, 10-trioxatridecane-1, 13-diamine (TTD), poly (alkyleneoxy) diamine (also referred to as polyetherdiamine), poly (ethyleneoxy) diamine, poly (propyleneoxy) diamine or a copolymer thereof, dicyandiamide and a derivative thereof, aminodihydrazide, adipic dihydrazide, isophthaloyl dihydrazide; guanidines, such as tetramethylguanidine. More preferably a dicyandiamide curing agent.

In order to promote the curing conditions and product performance of the epoxy product, in a preferred embodiment, the epoxy resin adhesive further comprises 1 to 3 parts by weight of a curing accelerator, such as N, N "- (methylenebis-4, 1-phenylene) bis (N ', N' -dimethylurea), N" - (4-methyl-1, 3-phenylene) bis (N ', N' -dimethylurea), 1-N substituted imidazole, 2-C substituted imidazole, and the like.

In order to further improve the product performance, the epoxy resin adhesive also comprises white carbon black, calcium carbonate, silica micropowder, carbon black, heat-conducting filler, titanium dioxide, flame-retardant filler, bentonite, talcum powder and other fillers.

According to another aspect of the invention, the application of the epoxy resin adhesive in the field of motor magnetic steel sheet bonding is provided.

The beneficial effects of the present invention are further illustrated by the following examples:

the following epoxy resin adhesives are prepared by mixing the components.

Example 1

The formulation of the epoxy adhesive in this example is as follows:

example 2

The formulation of the epoxy adhesive in this example is as follows:

example 3

The formulation of the epoxy adhesive in this example is as follows:

example 4

The formulation of the epoxy adhesive in this example is as follows:

example 5

The formulation of the epoxy adhesive in this example is as follows:

example 6

The formulation of the epoxy adhesive in this example is as follows:

example 7

The formulation of the epoxy adhesive in this example is as follows:

example 8

The formulation of the epoxy adhesive in this example is as follows:

example 9

The formulation of the epoxy adhesive in this example is as follows:

example 10

The formulation of the epoxy adhesive in this example is the same as that in example 9 except that: no core shell rubber toughening agent was added.

Example 11

The formulation of the epoxy adhesive in this example is the same as that in example 9 except that: replacing the anti-allergic agent 4-ethyl-4-soyabean ethyl sulfate morpholine with 4-ethyl-4-hydroxy ethyl sulfate morpholine.

Example 12

The formulation of the epoxy adhesive in this example is the same as that in example 9 except that: replacing the anti-allergic agent 4-ethyl-4-soyabean ethyl sulfate morpholine with 4-ethyl-4-ethyl sulfate morpholine.

Example 13

The formulation of the epoxy adhesive in this example is the same as that in example 9 except that: replacing the anti-allergic agent 4-ethyl-4-soyabean ethyl sulfate morpholine with 4-ethyl-4-ester ethyl sulfate morpholine.

Example 14

The formulation of the epoxy adhesive in this example was the same as in example 9, but no pregel adjuvant was added.

Example 15

The formulation in this example is the same as example 9 except that: the weight ratio of the core-shell rubber toughening agent to the CTBN toughening agent is 3:1, and the sum of the weight of the core-shell rubber toughening agent and the weight of the CTBN toughening agent is unchanged.

Example 16

The formulation in this example is the same as example 9 except that: the weight ratio of the core-shell rubber toughening agent to the CTBN toughening agent is 1:5, and the sum of the weight of the core-shell rubber toughening agent and the weight of the CTBN toughening agent is unchanged.

Example 17

The formulation in this example is the same as example 9 except that: the weight ratio of the core-shell rubber toughening agent to the CTBN toughening agent is 5:1, and the sum of the weight of the core-shell rubber toughening agent and the weight of the CTBN toughening agent is unchanged.

Example 18

The formulation in this example is the same as example 9 except that: the dosage of the curing agent is 21 parts, and the dosage of the antiallergic agent is 6 parts.

Example 19

The formulation in this example is the same as example 9 except that: the dosage of the curing agent is 1.04 parts, and the dosage of the antiallergic agent is 0.2 parts.

Example 20

The formulation in this example is the same as example 9 except that: the dosage of the curing agent is 24 parts, and the dosage of the antiallergic agent is 0.2 part.

Example 21

The formulation in this example is the same as example 9 except that: the amount of the pregel adjuvant is 1.5 parts.

Example 22

The formulation in this example is the same as example 9 except that: the amount of the pregel adjuvant is 9 parts.

Example 23

The formulation in this example is the same as example 9 except that: the amount of the pregel adjuvant is 0.5 part.

Example 24

The formulation in this example is the same as example 9 except that: the total amount of the toughening agent is 15 parts.

Example 25

The formulation in this example is the same as example 9 except that: the total amount of the flexibilizer is 4 parts

Example 25

The formulation in this example is the same as example 9 except that: the total amount of the flexibilizer is 1 part

Comparative example 1

The formulation of the epoxy adhesive in this comparative example was the same as example 9, except that 4-ethyl-4-soya-ethyl morpholine sulfate was not added.

And (3) performance characterization: the performance of the adhesive glue prepared in each embodiment and the comparative example is characterized, and the shear strength test method is according to GB/T7124; the glass transition temperature is carried out according to GB/T19466.2; and (3) odor test: allergy testing: sending the sample to a client workshop, and trying by a client worker and feeding back an experimental result; the test results are shown in tables 1 and 2:

TABLE 1

TABLE 2

The viscosity temperature profile of the epoxy adhesives of examples 9 and 14 were tested using a haake RS6000 rheometer and the results are shown in figure 1: note: a is example 9; b is example 14.

From the above description, it can be seen that the above-described embodiments of the present invention achieve the following technical effects:

1. preventing allergy, reducing odor, and reducing environmental pollution.

2. Preferably, the pre-gelling properties: in the process that the temperature is increased but the curing temperature is not reached, the colloid has good pre-gelling performance, can keep the original shape and cannot flow to cause the defects of gel shortage and the like.

3. The bonding strength is high: has good adhesive property to most base materials.

4. The toughness is good: the adhesive layer has good toughness, the peel strength can reach 5.12N/mm, and the failure mode is good.

5. The glass transition temperature of the cured colloid is 123.58 ℃, and the system has good toughness.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An epoxy resin adhesive comprises epoxy resin and a curing agent, and is characterized in that the epoxy resin adhesive also comprises an anti-sensitivity agent, and the anti-sensitivity agent has a structure shown in a formula I and/or a formula II:

wherein, R is₁And said R₂Each independently selected from alkyl, halogen, sulfonic acid, alicyclic group, phenyl, hydroxyl, alcyl, -R- (COO) -R, -R-COOH, R- (CO) -, R (COO) -or soy-based₃Selected from alkyl sulfate anions.

2. The epoxy adhesive according to claim 1, wherein the alkyl group is a linear or branched alkyl group of C1 to C12, preferably methyl, ethyl or propyl; the alicyclic group is a substituted or unsubstituted alicyclic group of C3-C12, preferably a cyclohexane group or a methylcyclohexane group; the alcohol alkyl is C1-C12 straight chain or branched chain alcohol alkyl, preferably hydroxyethyl, hydroxypropyl or hydroxybutyl; r is respectively and independently selected from alkyl or alkylene with 1-12 carbons, and the alkyl or alkylene is substituted or unsubstituted.

3. The epoxy adhesive of claim 1, wherein the anti-sensitivity agent is 4-ethyl-4-soyabean ethyl sulfate morpholine.

4. The epoxy resin adhesive according to any one of claims 1 to 3, wherein the weight ratio of the epoxy resin, the curing agent and the anti-sensitivity agent is 20-115: 2-7: 0.1-2.

5. The epoxy resin adhesive according to any one of claims 1 to 4, further comprising a pre-gelling aid, preferably the pre-gelling aid is acrylic polymer particles and/or acrylic core-shell particles, and the weight ratio of the pre-gelling aid to the epoxy resin is 3-18: 20-115.

6. The epoxy resin adhesive according to any one of claims 1 to 5, wherein the epoxy resin adhesive further comprises a toughening agent, preferably the toughening agent is a core-shell rubber toughening agent and/or a CTBN toughening agent, and more preferably the weight ratio of the core-shell rubber toughening agent to the CTBN toughening agent is 3: 1-1: 5.

7. The epoxy resin adhesive according to claim 6, wherein the weight ratio of the toughening agent to the epoxy resin is 8-30: 20-115.

8. The epoxy adhesive according to any one of claims 1 to 5, wherein the epoxy resin is one or more of a liquid epoxy resin, a solid epoxy resin and a semi-solid epoxy resin, and the curing agent is an amine curing agent.

9. The epoxy resin adhesive according to claim 8, wherein the liquid epoxy resin comprises bisphenol A type liquid epoxy resin and/or bisphenol F type liquid epoxy resin, preferably the epoxy resin comprises the liquid epoxy resin and the semi-solid epoxy resin, and the semi-solid epoxy resin accounts for 1-50% of the total weight of the epoxy resin.

10. Use of the epoxy resin adhesive according to any one of claims 1 to 9 in the field of bonding of magnetic steel sheets for electrical machines.