阅读说明：本技术 一种石墨双极板水场粘接用粘合剂及其制备方法 (Adhesive for adhering graphite bipolar plates in water field and preparation method thereof ) 是由 刘振 刘常福 韩冰峰 邢丹敏 李光伟 彭斌 刘超 徐家慧 于 2021-03-30 设计创作，主要内容包括：本发明提供一种石墨双极板水场粘接用粘合剂及其制备方法,所述粘合剂由下列物质按以下质量份数组成：环氧树脂10-15份,改性增韧性树脂30-35份,稀释剂8-12份,偶联剂0.6-0.9份,固化剂4-5份以及促进剂1份。本发明的技术方案解决了现有石墨双极板水腔粘接胶固化收缩会造成双极板翘曲变形的问题。(The invention provides an adhesive for adhering a graphite bipolar plate in a water field and a preparation method thereof, wherein the adhesive is prepared from the following substances in parts by mass: 10-15 parts of epoxy resin, 30-35 parts of modified toughening resin, 8-12 parts of diluent, 0.6-0.9 part of coupling agent, 4-5 parts of curing agent and 1 part of accelerator. The technical scheme of the invention solves the problem that the bipolar plate is warped and deformed due to the curing and shrinkage of the water cavity adhesive of the conventional graphite bipolar plate.)

1. The adhesive for adhering the graphite bipolar plate in the water field is characterized by comprising the following components in parts by mass: 10-15 parts of epoxy resin, 30-35 parts of modified toughening resin, 8-12 parts of diluent, 0.6-0.9 part of coupling agent, 4-5 parts of curing agent and 1 part of accelerator.

2. The adhesive for the water field bonding of the graphite bipolar plate according to claim 1, wherein the epoxy resin is a liquid epoxy resin comprising at least one of bisphenol a type epoxy resin and bisphenol F epoxy resin.

3. The adhesive for the water field bonding of the graphite bipolar plate as claimed in claim 1, wherein the modified toughening resin is at least one of a polycaprolactone-modified epoxy resin, a dimer acid-modified epoxy resin and a polyurethane-modified epoxy resin.

4. The adhesive for water field bonding of a graphite bipolar plate according to claim 1, wherein the diluent is at least one of carbon dodecyl glycidyl ether, benzyl glycidyl ester, dimer acid diglycidyl ester, and 1, 6-hexanediol diglycidyl ether.

5. The binder for the water field adhesion of a graphite bipolar plate as claimed in claim 1, wherein the coupling agent is at least one of 3- (2, 3-glycidoxy) propyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, and N-dodecyltrimethoxysilane.

6. The adhesive for the water field adhesion of the graphite bipolar plate as claimed in claim 1, wherein the curing agent is an imidazole curing agent or an amine curing agent.

7. The adhesive for the water field adhesion of the graphite bipolar plate as claimed in claim 1, wherein the accelerator is an imidazole accelerator or an amine accelerator.

8. The preparation method of the adhesive for the water field bonding of the graphite bipolar plate as claimed in claims 1 to 7, is characterized by comprising the following steps: and (2) uniformly mixing the mixture of the epoxy resin, the modified toughening resin, the diluent and the coupling agent by using a vacuum mixer at room temperature, adding the curing agent and the accelerator after uniform mixing, uniformly stirring in vacuum again to obtain the adhesive, and storing at-15 ℃.

Technical Field

The invention relates to the technical field of hydrogen fuel cell design, in particular to an adhesive for graphite bipolar plate water field adhesion and a preparation method thereof.

Background

The hydrogen fuel cell has excellent environmental friendliness and high working efficiency, and is one of ideal energy supply forms for reducing environmental pollution and replacing fossil fuels for human beings in the future. As an important component of a hydrogen fuel cell, a graphite bipolar plate needs to have good electrical conductivity, thermal conductivity, low gas permeability, high mechanical strength, flatness and other properties, and simultaneously, the graphite bipolar plate can meet the requirements of high-efficiency and mass production. With the increase of the power of the single stack of the hydrogen fuel cell, the volume ratio power is improved, and higher requirements are provided for the area and the thinning processing of the graphite bipolar plate. In the process of forming the complete bipolar plate by bonding the graphite unipolar plate water cavity, the problems of warping, deformation and the like of the bipolar plate are caused by the local stress concentration phenomenon generated by the curing and shrinkage of the bonding glue, the product qualification rate of the bipolar plate is directly reduced, the assembly of a fuel cell is influenced, and potential safety hazards are generated.

Disclosure of Invention

According to the technical problem that the bipolar plate warpage deformation is caused by curing shrinkage of the existing graphite bipolar plate water cavity adhesive, the adhesive for bonding the hydrogen fuel cell graphite bipolar plate and the preparation method thereof are provided, wherein the adhesive has strong bonding property, high toughness, good adhesive force and easy and rapid curing.

The technical means adopted by the invention are as follows:

the adhesive for the water field bonding of the graphite bipolar plate comprises the following components in parts by mass: 10-15 parts of epoxy resin, 30-35 parts of modified toughening resin, 8-12 parts of diluent, 0.6-0.9 part of coupling agent, 4-5 parts of curing agent and 1 part of accelerator.

Further, the epoxy resin is a liquid epoxy resin, and comprises at least one of bisphenol A epoxy resin and bisphenol F epoxy resin.

Further, the modified toughening resin is at least one of polycaprolactone-modified epoxy resin, dimer acid-modified epoxy resin and polyurethane-modified epoxy resin.

Further, the diluent is at least one of carbon dodecyl glycidyl ether, benzyl glycidyl ester, dimer acid diglycidyl ester and 1, 6-hexanediol diglycidyl ether.

Further, the coupling agent is at least one of 3- (2, 3-epoxypropoxy) propyl trimethoxy silane, 3-glycidoxypropyl triethoxy silane and N-dodecyl trimethoxy silane.

Further, the curing agent is an imidazole curing agent or an amine curing agent.

Further, the accelerator is an imidazole accelerator or an amine accelerator.

The invention also provides a preparation method of the adhesive for adhering the graphite bipolar plate in the water field, which comprises the following steps: and (2) uniformly mixing the mixture of the epoxy resin, the modified toughening resin, the diluent and the coupling agent by using a vacuum mixer at room temperature, adding the latent curing agent and the accelerator after uniform mixing, uniformly stirring in vacuum again to obtain the adhesive, and storing at-15 ℃.

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

according to the adhesive for adhering the graphite bipolar plate in the water field and the preparation method thereof, the temperature required by curing of the adhesive is low, the speed is high, the adhesive can be cured within 10 minutes at 100 ℃ and within 6 minutes at 120 ℃, and the production efficiency is improved; the adhesive has good flexibility and low shrinkage rate in the curing process, and the volume shrinkage rate of the cured product is less than or equal to 0.5 percent; the viscosity of the adhesive is 38000-52000mPa & s, and no solvent is volatilized in the curing process; meanwhile, the preparation method of the adhesive is simple and easy to implement, and is easy for automatic dispensing construction operation.

Based on the reasons, the invention can be widely popularized in the field of fuel cell bipolar plate bonding.

Detailed Description

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

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. Any specific values in all examples shown and discussed herein are to be construed as exemplary only and not as limiting. Thus, other examples of the exemplary embodiments may have different values.

In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc., are merely for convenience in describing the present invention and for simplicity in description, and in the case of not being stated to the contrary, these orientation words do not indicate and imply that the device or element being referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore, should not be taken as limiting the scope of the present invention: the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the device. For example, if a device is turned over, devices described as "above" or "above" other devices or configurations would then be oriented "below" or "beneath" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and the terms have no special meanings unless otherwise stated, and therefore, the scope of the present invention should not be construed as being limited.

The invention provides an adhesive for adhering a graphite bipolar plate in a water field, which comprises the following components in parts by mass: 10-15 parts of epoxy resin, 30-35 parts of modified toughening resin, 8-12 parts of diluent, 0.6-0.9 part of coupling agent, 4-5 parts of curing agent and 1 part of accelerator.

Further, the epoxy resin is a liquid epoxy resin, and comprises at least one of bisphenol A epoxy resin and bisphenol F epoxy resin.

Further, the modified toughening resin is at least one of polycaprolactone-modified epoxy resin, dimer acid-modified epoxy resin and polyurethane-modified epoxy resin.

Further, the diluent is at least one of carbon dodecyl glycidyl ether, benzyl glycidyl ester, dimer acid diglycidyl ester and 1, 6-hexanediol diglycidyl ether.

Further, the coupling agent is at least one of 3- (2, 3-epoxypropoxy) propyl trimethoxy silane, 3-glycidoxypropyl triethoxy silane and N-dodecyl trimethoxy silane.

Further, the curing agent is an imidazole curing agent or an amine curing agent.

Further, the accelerator is an imidazole accelerator or an amine accelerator.

The invention also provides a preparation method of the adhesive for adhering the graphite bipolar plate in the water field, which comprises the following steps: and (2) uniformly mixing the mixture of the epoxy resin, the modified toughening resin, the diluent and the coupling agent by using a vacuum mixer at room temperature, adding the latent curing agent and the accelerator after uniform mixing, uniformly stirring in vacuum again to obtain the adhesive, and storing at-15 ℃.

Example 1

The adhesive of the embodiment comprises the following substances in parts by mass: 15 parts of epoxy resin, 30 parts of modified toughening resin, 8 parts of diluent, 0.6 part of coupling agent, 4 parts of curing agent and 1 part of accelerator.

Further, in this embodiment, the epoxy resin is a bisphenol a type epoxy resin.

Further, in this embodiment, the modified toughening resin is a mixture of polycaprolactone-modified epoxy resin and dimer acid-modified epoxy resin, and the ratio of the polycaprolactone-modified epoxy resin to the dimer acid-modified epoxy resin is 6: 1.

Further, in this embodiment, the diluent is a mixture of carbon dodecyl glycidyl ether and dimer acid diglycidyl ester, and the ratio of the carbon dodecyl glycidyl ether to the dimer acid diglycidyl ester is 3: 1.

Further, in this embodiment, the coupling agent is 3- (2, 3-glycidoxy) propyltrimethoxysilane.

In this embodiment, the curing agent is an imidazole curing agent.

Further, in this embodiment, the accelerator is an imidazole accelerator.

The preparation method of the adhesive for the water field bonding of the graphite bipolar plate comprises the following steps:

(1) accurately weighing the epoxy resin, the modified toughening resin, the diluent and the coupling agent according to the formula amount at room temperature (25 ℃), adding into a vacuum stirrer, and physically mixing for 30min at the stirring speed of 1000 revolutions per minute;

(2) adding the curing agent and the accelerator in the formula amount into a stirrer, physically mixing for 45min at the stirring speed of 500 revolutions per minute, standing for defoaming to obtain the adhesive for adhering the graphite bipolar plate in the water field, and storing at-15 ℃ in a refrigerator.

Example 2

The adhesive of the embodiment comprises the following substances in parts by mass: 10 parts of epoxy resin, 32 parts of modified toughening resin, 12 parts of diluent, 0.9 part of coupling agent, 5 parts of curing agent and 1 part of accelerator.

Further, in this embodiment, the epoxy resin is bisphenol a epoxy resin and bisphenol F epoxy resin, and the ratio of the two is 3: 2.

Further, in this embodiment, the modified toughening resin is a mixture of dimer acid-modified epoxy resin and polyurethane-modified epoxy resin, and the ratio of the dimer acid-modified epoxy resin to the polyurethane-modified epoxy resin is 3: 2.

Further, in this example, the diluent is benzyl glycidyl ester and 1, 6-hexanediol diglycidyl ether at a ratio of 4: 3.

Further, in this embodiment, the coupling agent is a mixture of 3-glycidoxypropyltriethoxysilane and N-dodecyltrimethoxysilane at a ratio of 2: 1.

In this embodiment, the curing agent is an imidazole curing agent.

Further, in this embodiment, the accelerator is an imidazole accelerator.

The preparation method of the adhesive for the water field bonding of the graphite bipolar plate comprises the following steps:

(1) accurately weighing the epoxy resin, the modified toughening resin, the diluent and the coupling agent according to the formula amount at room temperature (25 ℃), adding into a vacuum stirrer, and physically mixing for 30min at the stirring speed of 1000 revolutions per minute;

(2) adding the curing agent and the accelerator in the formula amount into a stirrer, physically mixing for 45min at the stirring speed of 500 revolutions per minute, standing for defoaming to obtain the adhesive for adhering the graphite bipolar plate in the water field, and storing at-15 ℃ in a refrigerator.

Example 3

The adhesive of the embodiment comprises the following substances in parts by mass: 12 parts of epoxy resin, 35 parts of modified toughening resin, 10 parts of diluent, 0.8 part of coupling agent, 5 parts of curing agent and 1 part of accelerator.

Further, in this embodiment, the epoxy resin is bisphenol a epoxy resin and bisphenol F epoxy resin, and the ratio of the two is 1: 2.

Further, in this embodiment, the modified toughening resin is a mixture of polycaprolactone-modified epoxy resin and polyurethane-modified epoxy resin, and the ratio of the two is 2: 3.

Further, in this embodiment, the diluent is carbon dodecyl glycidyl ether and 1, 6-hexanediol diglycidyl ether at a ratio of 1:1

Further, in this embodiment, the coupling agent is 3-glycidoxypropyltriethoxysilane.

In this embodiment, the curing agent is an imidazole curing agent.

Further, in this embodiment, the accelerator is an imidazole accelerator.

The preparation method comprises the following steps:

(1) accurately weighing the epoxy resin, the modified toughening resin, the diluent and the coupling agent according to the formula amount at room temperature (25 ℃), adding into a vacuum stirrer, and physically mixing for 30min at the stirring speed of 1000 revolutions per minute;

(2) adding the curing agent and the accelerator in the formula amount into a stirrer, physically mixing for 45min at the stirring speed of 500 revolutions per minute, standing for defoaming to obtain the adhesive for adhering the graphite bipolar plate in the water field, and storing at-15 ℃ in a refrigerator.

Physical property phenotype and performance tests were performed on the adhesives prepared in examples 1 to 3, respectively, and the test results are summarized in table 1:

table 1 examples 1-3 sample test results

As can be seen from the test results in table 1, the adhesive of example 3 has the best performance and is referred to as the best formulation embodiment of the present invention.

The adhesive provided by the invention has the advantages of good flexibility, high bonding strength, no volatilization of volatile solvents and low volume shrinkage rate, and can meet the bonding construction requirements of the graphite bipolar plate of the hydrogen fuel cell.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.