Epoxy resin composite material and application thereof

Abstract

The invention relates to an epoxy resin composite material and application thereof, and relates to the technical field of epoxy resin materials.The preparation method of the epoxy resin composite material comprises the following steps that epoxy resin, a curing agent and an accelerant are stirred and mixed, and a first mixture is obtained; stirring and mixing the first mixture and a composite reinforcing material to obtain a second mixture; and carrying out vacuum defoaming and curing on the second mixture to obtain the epoxy resin composite material, wherein the composite reinforcing material is obtained by treating sulfydryl modified fibers and imidazolium ionic liquid through a silane coupling agent. The composite reinforcing material obtained by treating the sulfydryl modified fiber and the imidazolium ionic liquid through the silane coupling agent is constructed and introduced into an epoxy resin matrix, so that the heat-conducting property and the mechanical property of the obtained epoxy resin composite material are remarkably improved, and the defects in the prior art are overcome.

Description

Technical Field

[0001] The present invention relates to the technical field of epoxy resin materials, and in particular to an epoxy resin composite material and application thereof. Background Art

[0002] In recent years, with the rapid development of new energy, smart grid and power electronics technology, power electronic equipment represented by solid-state transformers are increasingly used in renewable energy grids. These devices tend to be high-voltage, high-frequency, and high-power density, resulting in a sharp increase in heat generation per unit volume, which puts higher requirements on the performance of packaging insulation materials. Packaging insulation materials need to have not only good insulation properties, but also excellent thermal conductivity to ensure stable operation and long life of the equipment.

[0003] Epoxy resin has been widely used in packaging insulation materials for power electronic equipment due to its excellent insulation properties, good processing properties and relatively low cost. However, the thermal conductivity of traditional epoxy resin is low, which makes it difficult to meet the heat dissipation requirements of high-voltage and high-frequency equipment. In addition, the existing research on epoxy resin modification mainly focuses on using nanomaterials such as nano-silicon dioxide, nano-silicon carbide, nano-aluminum oxide, carbon nanotubes, etc. to improve the mechanical properties of epoxy resin composite materials such as toughness. However, nanomaterials are prone to agglomeration due to their large specific surface area and high surface energy, which affects the mechanical properties of epoxy resin. Summary of the invention

[0004] In order to solve the above problems, the present invention provides an epoxy resin composite material and application thereof.

[0005] In a first aspect, the present invention provides an epoxy resin composite material, wherein a method for preparing the epoxy resin composite material comprises the following steps:

[0006] Stirring and mixing the epoxy resin, the curing agent and the accelerator to obtain a first mixture;

[0007] Stirring and mixing the first mixed material and the composite reinforcement material to obtain a second mixed material;

[0008] vacuum degassing and curing the second mixed material to obtain the epoxy resin composite material;

[0009] The composite reinforcement material is obtained by treating mercapto-modified fibers and imidazole ionic liquid with a silane coupling agent.

[0010] Furthermore, the preparation method of the composite reinforced material comprises the following process:

[0011] Adding a silane coupling agent to an ethanol aqueous solution having a pH of 3.5 to 4.5 and stirring and mixing to obtain a silane coupling agent solution;

[0012] The mercapto-modified fiber and the imidazole ionic liquid are added into the silane coupling agent solution, heated and stirred, and then evaporated and dried to obtain the composite reinforcement material.

[0013] Furthermore, the weight ratio of the silane coupling agent, the ethanol aqueous solution, the mercapto-modified fiber and the imidazole ionic liquid is (2-5):(10-15):(0.5-1):(2-3).

[0014] Furthermore, the working condition parameters of the heating and stirring include: a temperature of 60 to 70° C. and a time of 1 to 2 hours.

[0015] Furthermore, the preparation of the ethanol aqueous solution includes the following process: adding anhydrous acetic acid to an ethanol aqueous solution with a volume fraction of 75 to 85%, adjusting the pH to 3.5 to 4.5, and obtaining the ethanol aqueous solution; the silane coupling agent includes silane coupling agent KH-570 and silane coupling agent KH-550; the thiol-modified fiber includes thiol-modified chopped glass fiber; the imidazole ionic liquid includes at least one of 1-octyl-3-methylimidazolium bromide and 1-decyl-3-methylimidazolium bromide.

[0016] Furthermore, the weight ratio of the epoxy resin, the curing agent, the accelerator and the composite reinforcement material is 100:(25-35):(1-5):(10-20).

[0017] Furthermore, the epoxy resin includes bisphenol A epoxy resin.

[0018] Furthermore, the curing agent includes at least one of 3,3'-diaminodiphenyl sulfone, 1,3-diaminobenzene and 1,4-diaminobenzene; and the accelerator includes 2-ethyl-4-methylimidazole.

[0019] Furthermore, the working condition parameters of the curing include: a curing temperature of 115 to 130° C. and a curing time of 4 to 7 hours.

[0020] In a second aspect, the present invention provides a use of the epoxy resin composite material described in any one of the first aspects in preparing a packaging insulating material.

[0021] The above technical solution provided by the embodiment of the present invention has at least the following advantages compared with the prior art:

[0022] An embodiment of the present invention provides an epoxy resin composite material. The present invention constructs a composite reinforcement material obtained by treating mercapto-modified fibers and imidazole ionic liquids with a silane coupling agent, and introduces the composite reinforcement material into an epoxy resin matrix, thereby significantly improving the thermal conductivity and mechanical properties of the obtained epoxy resin composite material, thereby making up for the shortcomings of the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0025] Figure 1 A schematic flow chart of a method for preparing an epoxy resin composite material provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0028] In a first aspect, the present invention provides an epoxy resin composite material, such as Figure 1 As shown, the preparation method of the epoxy resin composite material comprises the following steps:

[0029] Stirring and mixing the epoxy resin, the curing agent and the accelerator to obtain a first mixture;

[0030] Stirring and mixing the first mixed material and the composite reinforcement material to obtain a second mixed material;

[0031] vacuum degassing and curing the second mixed material to obtain the epoxy resin composite material;

[0032] The composite reinforcement material is obtained by treating mercapto-modified fibers and imidazole ionic liquid with a silane coupling agent.

[0033] An embodiment of the present invention provides an epoxy resin composite material. The present invention constructs a composite reinforcement material obtained by treating mercapto-modified fibers and imidazole ionic liquids with a silane coupling agent, and introduces the composite reinforcement material into an epoxy resin matrix, thereby significantly improving the thermal conductivity and mechanical properties of the obtained epoxy resin composite material, thereby making up for the shortcomings of the prior art.

[0034] In some specific embodiments, the bisphenol A epoxy resin can be directly purchased from the market or prepared by using existing bisphenol A epoxy resin preparation methods such as polycondensation of bisphenol A and epichlorohydrin under the action of an alkaline catalyst (usually NaOH).

[0035] In some specific embodiments, the mercapto-modified fiber can be modified according to the mercaptosilane sol-gel method to obtain modified mercapto groups on the fiber surface. This method is reported in the master's thesis "Mercapto Modification of Polyester Fiber and Polyamide Fiber Surface and Preparation of Chemical Silver-plated Fiber" published by Donghua University in 2012. Another treatment method is to first treat the fiber with alkali to obtain hydroxyl groups on the fiber surface, and then react with a mercaptosilane coupling agent. This method is reported in the paper "Research on Mercapto-Modified PET Fiber and Chemical Silver-plated Electromagnetic Shielding Cloth" published in the journal "Printing and Dyeing Auxiliary Agents" in March 2011.

[0036] In some specific embodiments, the method for preparing the composite reinforced material comprises the following process:

[0037] Adding a silane coupling agent to an ethanol aqueous solution having a pH of 3.5 to 4.5 and stirring and mixing to obtain a silane coupling agent solution;

[0038] The mercapto-modified fiber and the imidazole ionic liquid are added into the silane coupling agent solution, heated and stirred, and then evaporated and dried to obtain the composite reinforcement material.

[0039] In some specific embodiments, the weight ratio of the silane coupling agent, the ethanol aqueous solution, the mercapto-modified fiber and the imidazole ionic liquid is (2-5):(10-15):(0.5-1):(2-3), preferably 3:13:0.8:2.5.

[0040] In some specific embodiments, the working condition parameters of the heating and stirring include: a temperature of 60 to 70° C. and a time of 1 to 2 hours.

[0041] In some specific embodiments, the preparation of the ethanol aqueous solution includes the following process: adding anhydrous acetic acid to an ethanol aqueous solution with a volume fraction of 75 to 85%, adjusting the pH to 3.5 to 4.5, to obtain the ethanol aqueous solution; the silane coupling agent includes silane coupling agent KH-570 and silane coupling agent KH-550; the thiol-modified fiber includes thiol-modified chopped glass fiber; the imidazole ionic liquid includes at least one of 1-octyl-3-methylimidazolium bromide and 1-decyl-3-methylimidazolium bromide.

[0042] In some specific embodiments, the weight ratio of the epoxy resin, the curing agent, the accelerator and the composite reinforcement material is 100:(25-35):(1-5):(10-20), preferably 100:30:2:15.

[0043] In some specific embodiments, the epoxy resin includes bisphenol A epoxy resin.

[0044] In some specific embodiments, the curing agent includes at least one of 3,3'-diaminodiphenyl sulfone, 1,3-diaminobenzene and 1,4-diaminobenzene; and the accelerator includes 2-ethyl-4-methylimidazole.

[0045] In some specific embodiments, the working condition parameters of the curing include: a curing temperature of 115 to 130° C. and a curing time of 4 to 7 hours.

[0046] In a second aspect, based on a general inventive concept, the present invention provides a use of the epoxy resin composite material described in any one of the first aspects in preparing a packaging insulating material.

[0047] It should be noted that the raw material components involved in the epoxy resin composite materials and their applications provided by the embodiments of the present invention, unless otherwise specified or described, can be directly purchased from the market or can be prepared in-house according to existing preparation methods; at the same time, the operating steps involved in the preparation method, unless otherwise specified or described, can be carried out according to existing epoxy resin composite material preparation methods.

[0048] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are intended only to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods in the following examples that do not specify specific conditions are usually measured according to national standards. If there is no corresponding national standard, then the conditions recommended by the manufacturer are followed.

[0049] Example 1

[0050] This example provides an epoxy resin composite material, and the preparation method of the epoxy resin composite material comprises the following steps:

[0051] Step (1), preparing a composite reinforcement material: adding anhydrous acetic acid to an ethanol aqueous solution with a volume fraction of 80%, adjusting the pH to 4.0, and obtaining an ethanol aqueous solution; adding a silane coupling agent to the ethanol aqueous solution and stirring and mixing to obtain a silane coupling agent solution; adding a thiol-modified fiber and an imidazole ionic liquid to the silane coupling agent solution and heating and stirring, the heating and stirring temperature is 65° C., the heating and stirring time is 1.5 hours, and then evaporating and drying to obtain the composite reinforcement material; wherein the weight ratio of the silane coupling agent, the ethanol aqueous solution, the thiol-modified fiber and the imidazole ionic liquid is 3:13:0.8:2.5, the silane coupling agent is silane coupling agent KH-570, the thiol-modified fiber is thiol-modified chopped glass fiber, and the imidazole ionic liquid is 1-octyl-3-methylimidazolium bromide;

[0052] Step (2), preparing an epoxy resin composite material: stirring and mixing an epoxy resin, a curing agent and an accelerator, then adding a composite reinforcement material and continuing to stir and mix to obtain a mixture; vacuum degassing the mixture until there are no bubbles, then heating and curing to obtain the epoxy resin composite material; wherein the weight ratio of the epoxy resin, the curing agent, the accelerator and the composite reinforcement material is 100:30:2:15, the epoxy resin is a bisphenol A epoxy resin, the curing agent is 3,3'-diaminodiphenyl sulfone, the accelerator is 2-ethyl-4-methylimidazole, and the curing working condition parameters include: a curing temperature of 125°C and a curing time of 6 hours.

[0053] Example 2

[0054] This example provides an epoxy resin composite material, and the preparation method of the epoxy resin composite material comprises the following steps:

[0055] Step (1), preparing a composite reinforcement material: adding anhydrous acetic acid to an ethanol aqueous solution with a volume fraction of 75%, adjusting the pH to 4.5, and obtaining an ethanol aqueous solution; adding a silane coupling agent to the ethanol aqueous solution and stirring and mixing to obtain a silane coupling agent solution; adding a thiol-modified fiber and an imidazole ionic liquid to the silane coupling agent solution and heating and stirring, the heating and stirring temperature is 60° C., the heating and stirring time is 2 hours, and then evaporating and drying to obtain the composite reinforcement material; wherein the weight ratio of the silane coupling agent, the ethanol aqueous solution, the thiol-modified fiber and the imidazole ionic liquid is 2:10:0.5:3, the silane coupling agent is silane coupling agent KH-550, the thiol-modified fiber is thiol-modified chopped glass fiber, and the imidazole ionic liquid is 1-decyl-3-methylimidazolium bromide;

[0056] Step (2), preparing an epoxy resin composite material: stirring and mixing an epoxy resin, a curing agent and an accelerator, then adding a composite reinforcement material and continuing to stir and mix to obtain a mixture; vacuum degassing the mixture until there are no bubbles, then heating and curing to obtain the epoxy resin composite material; wherein the weight ratio of the epoxy resin, the curing agent, the accelerator and the composite reinforcement material is 100:25:1:10, the epoxy resin is bisphenol A epoxy resin, the curing agent is 1,3-diaminobenzene, the accelerator is 2-ethyl-4-methylimidazole, and the working condition parameters of the curing include: a curing temperature of 125°C and a curing time of 6 hours.

[0057] Example 3

[0058] This example provides an epoxy resin composite material, and the preparation method of the epoxy resin composite material comprises the following steps:

[0059] Step (1), preparing a composite reinforcement material: adding anhydrous acetic acid to an ethanol aqueous solution with a volume fraction of 85%, adjusting the pH to 3.5, and obtaining an ethanol aqueous solution; adding a silane coupling agent to the ethanol aqueous solution and stirring and mixing to obtain a silane coupling agent solution; adding a thiol-modified fiber and an imidazole ionic liquid to the silane coupling agent solution and heating and stirring, the heating and stirring temperature is 70° C., the heating and stirring time is 1 hour, and then evaporating and drying to obtain the composite reinforcement material; wherein the weight ratio of the silane coupling agent, the ethanol aqueous solution, the thiol-modified fiber and the imidazole ionic liquid is 5:15:1:2, the silane coupling agent is silane coupling agent KH-550, the thiol-modified fiber is thiol-modified chopped glass fiber, and the imidazole ionic liquid is 1-decyl-3-methylimidazolium bromide;

[0060] Step (2), preparing an epoxy resin composite material: stirring and mixing an epoxy resin, a curing agent and an accelerator, then adding a composite reinforcement material and continuing to stir and mix to obtain a mixture; vacuum degassing the mixture until there are no bubbles, then heating and curing to obtain the epoxy resin composite material; wherein the weight ratio of the epoxy resin, the curing agent, the accelerator and the composite reinforcement material is 100:35:5:20, the epoxy resin is bisphenol A epoxy resin, the curing agent is 1,3-diaminobenzene, the accelerator is 2-ethyl-4-methylimidazole, and the working condition parameters of the curing include: a curing temperature of 125°C and a curing time of 6 hours.

[0061] Comparative Example 1

[0062] This example provides an epoxy resin composite material, which is different from Example 1 only in that the mercapto-modified fiber is replaced by unmodified chopped glass fiber; the remaining steps and parameters are the same.

[0063] The preparation method of the epoxy resin composite material comprises the following steps:

[0064] Step (1), preparing a composite reinforcement material: adding anhydrous acetic acid to an ethanol aqueous solution with a volume fraction of 80%, adjusting the pH to 4.0, and obtaining an ethanol aqueous solution; adding a silane coupling agent to the ethanol aqueous solution and stirring and mixing to obtain a silane coupling agent solution; adding short glass fibers and an imidazole ionic liquid to the silane coupling agent solution and heating and stirring, the heating and stirring temperature is 65° C., the heating and stirring time is 1.5 hours, and then evaporating and drying to obtain the composite reinforcement material; wherein the weight ratio of the silane coupling agent, the ethanol aqueous solution, the short glass fibers and the imidazole ionic liquid is 3:13:0.8:2.5, the silane coupling agent is silane coupling agent KH-570, the thiol-modified fiber is thiol-modified short glass fiber, and the imidazole ionic liquid is 1-octyl-3-methylimidazolium bromide;

[0065] Step (2), preparing an epoxy resin composite material: stirring and mixing an epoxy resin, a curing agent and an accelerator, then adding a composite reinforcement material and continuing to stir and mix to obtain a mixture; vacuum degassing the mixture until there are no bubbles, then heating and curing to obtain the epoxy resin composite material; wherein the weight ratio of the epoxy resin, the curing agent, the accelerator and the composite reinforcement material is 100:30:2:15, the epoxy resin is a bisphenol A epoxy resin, the curing agent is 3,3'-diaminodiphenyl sulfone, the accelerator is 2-ethyl-4-methylimidazole, and the curing working condition parameters include: a curing temperature of 125°C and a curing time of 6 hours.

[0066] Comparative Example 2

[0067] This example provides an epoxy resin composite material, which is different from Example 1 only in that the weight ratio of the silane coupling agent, the ethanol aqueous solution, the thiol-modified fiber and the imidazole ionic liquid is adjusted to 3:13:2.5:0.8; the remaining steps and parameters are the same.

[0068] The preparation method of the epoxy resin composite material comprises the following steps:

[0069] Step (1), preparing a composite reinforcement material: adding anhydrous acetic acid to an ethanol aqueous solution with a volume fraction of 80%, adjusting the pH to 4.0, and obtaining an ethanol aqueous solution; adding a silane coupling agent to the ethanol aqueous solution and stirring and mixing to obtain a silane coupling agent solution; adding a thiol-modified fiber and an imidazole ionic liquid to the silane coupling agent solution and heating and stirring, the heating and stirring temperature is 65° C., the heating and stirring time is 1.5 hours, and then evaporating and drying to obtain the composite reinforcement material; wherein the weight ratio of the silane coupling agent, the ethanol aqueous solution, the thiol-modified fiber and the imidazole ionic liquid is 3:13:2.5:0.8, the silane coupling agent is silane coupling agent KH-570, the thiol-modified fiber is thiol-modified chopped glass fiber, and the imidazole ionic liquid is 1-octyl-3-methylimidazolium bromide;

[0070] Step (2), preparing an epoxy resin composite material: stirring and mixing an epoxy resin, a curing agent and an accelerator, then adding a composite reinforcement material and continuing to stir and mix to obtain a mixture; vacuum degassing the mixture until there are no bubbles, then heating and curing to obtain the epoxy resin composite material; wherein the weight ratio of the epoxy resin, the curing agent, the accelerator and the composite reinforcement material is 100:30:2:15, the epoxy resin is a bisphenol A epoxy resin, the curing agent is 3,3'-diaminodiphenyl sulfone, the accelerator is 2-ethyl-4-methylimidazole, and the curing working condition parameters include: a curing temperature of 125°C and a curing time of 6 hours.

[0071] Test Case

[0072] This example aims to compare and analyze the thermal conductivity and mechanical properties of the epoxy resin composite materials provided by Examples 1 to 3 and Comparative Examples 1 to 2. The thermal conductivity test was performed according to the ASTM D5470-2012 test standard, and the tensile strength test was performed according to the ASTM D638 test standard. The test results are shown in Table 1 below.

[0073] Table 1

[0074] serial number Thermal conductivity (W / (m·K)) Tensile strength(MPa) Example 1 2.19 141.8 Example 2 1.76 122.9 Example 3 1.87 127.5 Comparative Example 1 0.56 80.7 Comparative Example 2 0.85 101.2

[0075] Various embodiments of the present invention may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present invention; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0076] The foregoing is merely a specific embodiment of the present invention, which enables those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features claimed herein.

Claims

1. An epoxy resin composite material, characterized in that: The preparation method of the epoxy resin composite material comprises the following steps: Stirring and mixing the epoxy resin, the curing agent and the accelerator to obtain a first mixture; Stirring and mixing the first mixed material and the composite reinforcement material to obtain a second mixed material; vacuum degassing and curing the second mixed material to obtain the epoxy resin composite material; The composite reinforcement material is obtained by treating mercapto-modified fibers and imidazole ionic liquid with a silane coupling agent.

2. The epoxy resin composite material according to claim 1, characterized in that: The preparation method of the composite reinforced material comprises the following steps: Adding a silane coupling agent to an ethanol aqueous solution having a pH of 3.5 to 4.5 and stirring and mixing to obtain a silane coupling agent solution; The mercapto-modified fiber and the imidazole ionic liquid are added into the silane coupling agent solution, heated and stirred, and then evaporated and dried to obtain the composite reinforcement material.

3. The epoxy resin composite material according to claim 2, characterized in that: The weight ratio of the silane coupling agent, the ethanol aqueous solution, the mercapto-modified fiber and the imidazole ionic liquid is (2-5):(10-15):(0.5-1):(2-3).

4. The epoxy resin composite material according to claim 2, characterized in that: The working condition parameters of the heating and stirring include: temperature of 60-70° C. and time of 1-2 hours.

5. The epoxy resin composite material according to claim 2, characterized in that: The preparation of the ethanol aqueous solution comprises the following process: anhydrous acetic acid is added dropwise to an ethanol aqueous solution with a volume fraction of 75 to 85%, and the pH is adjusted to 3.5 to 4.5 to obtain the ethanol aqueous solution; the silane coupling agent comprises silane coupling agent KH-570 and silane coupling agent KH-550; the thiol-modified fiber comprises thiol-modified chopped glass fiber; and the imidazole ionic liquid comprises at least one of 1-octyl-3-methylimidazolium bromide and 1-decyl-3-methylimidazolium bromide.

6. The epoxy resin composite material according to claim 1, characterized in that: The weight ratio of the epoxy resin, the curing agent, the accelerator and the composite reinforcement material is 100:(25-35):(1-5):(10-20).

7. The epoxy resin composite material according to claim 1, characterized in that: The epoxy resin includes bisphenol A type epoxy resin.

8. The epoxy resin composite material according to claim 1, characterized in that: The curing agent includes at least one of 3,3'-diaminodiphenyl sulfone, 1,3-diaminobenzene and 1,4-diaminobenzene; and the accelerator includes 2-ethyl-4-methylimidazole.

9. The epoxy resin composite material according to claim 1, characterized in that: The working condition parameters of the curing include: a curing temperature of 115 to 130° C. and a curing time of 4 to 7 hours.

10. Use of the epoxy resin composite material according to any one of claims 1 to 9 in preparing packaging insulating materials.

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