High-hardness high-wear-resistance epoxy resin composite material and preparation method thereof

Abstract

The invention discloses a high-hardness and high-wear-resistance epoxy resin composite material and a preparation method thereof, and relates to the technical field of polymer composites.The preparation method is characterized by comprising the steps that S1, wear-resistant filler is dispersed in an epoxy resin curing agent in proportion, and a modified epoxy curing agent is obtained through vacuum stirring and mixing; s2, mixing an epoxy diluent, a defoaming agent and an epoxy resin monomer, and performing vacuum stirring and mixing to obtain a modified epoxy main agent; s3, uniformly stirring and mixing the modified epoxy main agent and the modified curing agent in proportion at low temperature in vacuum, putting the mixture into a low-temperature drying box to primarily cure the system, and then curing at high temperature to obtain the wear-resistant and heat-resistant epoxy resin composite material. The epoxy resin and the curing agent adopted in the invention have higher functionality and higher benzene ring content, the adopted filler has higher wear resistance, and a more optimized curing process is used, so that the hardness and wear resistance of the composite resin are greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of polymer composite materials, and more specifically, to a high-hardness and high-wear-resistant epoxy resin composite material and a preparation method thereof. Background Art

[0002] High-hardness and high-wear-resistant epoxy resin is a special polymer material with ultra-high hardness and ultra-high wear resistance. The hardness and wear resistance of the resin are effectively improved through formula improvement, the use of high-hardness and high-wear-resistant fillers and special preparation processes. In the field of engineering technology, there are a series of problems such as material wear, energy loss and product failure caused by long-term friction. Therefore, the development of high-hardness and high-wear-resistant composite materials has always been an urgent need in the fields of materials science and engineering technology. With the growing demand for lightweight and high-performance components in the field of engineering technology, polymer composite materials have been widely used in many engineering application fields, especially in the field of wear-resistant materials, due to their unique properties.

[0003] Epoxy resin is an important thermosetting resin with good physical and mechanical properties, chemical resistance, and electrical insulation properties. Therefore, it is widely used in coatings, adhesives, fiberglass, laminates, electronic casting, potting, encapsulation and other fields. However, due to the high friction coefficient (0.4-0.6) and specific wear rate of epoxy resin itself, its application in the field of wear reduction and wear resistance is limited. With the development of science and technology, the engineering application field has put forward higher requirements on the wear resistance and hardness of epoxy resin composite materials. However, most of the modified epoxy resin composite materials currently cannot achieve excellent wear resistance and high hardness at the same time.

[0004] The patent with publication number CN115850911A discloses a high-hardness and corrosion-resistant epoxy resin, which uses modified silicon dioxide and titanium dioxide to enhance the wear resistance of the epoxy resin, but does not significantly improve the hardness of the resin. The patent with publication number CN116496606A discloses a method for preparing a highly wear-resistant epoxy resin-silicon carbide composite material, which uses silicon carbide to improve the wear resistance, high temperature resistance and impact resistance of bisphenol A epoxy resin, but the wear resistance improvement effect is unstable and the mechanical properties are not ideal. Therefore, the development of a polymer-based composite material with both high hardness and high wear resistance has important scientific value and application prospects. Summary of the invention

[0005] The purpose of the present invention is to provide a high-hardness and high-wear-resistant epoxy resin composite material and a preparation method thereof to solve the above problems.

[0006] The above technical objectives of the present invention are achieved through the following technical solutions:

[0007] The first aspect of the present invention provides a method for preparing a high-hardness and high-wear-resistant epoxy resin composite material, which is characterized by comprising the following steps:

[0008] S1. The wear-resistant filler is dispersed in the epoxy resin curing agent in proportion, and the modified epoxy curing agent is obtained by vacuum stirring and mixing, wherein the mass ratio of the wear-resistant filler to the epoxy resin curing agent is 0.17:1 to 0.5:1;

[0009] S2. The epoxy diluent, the defoamer and the epoxy resin monomer are mixed, and the modified epoxy main agent is obtained by mixing by vacuum stirring, the mass ratio of the epoxy diluent to the epoxy main agent is 1:9, and the content of the defoamer in the modified epoxy main agent is 0.1%;

[0010] S3. After the modified epoxy main agent and the modified curing agent are mixed uniformly in proportion by vacuum low-temperature stirring, the system is placed in a low-temperature drying oven for initial curing, and then cured at high temperature to obtain a wear-resistant and heat-resistant epoxy resin composite material; the mass ratio of the modified epoxy main agent to the modified curing agent is 0.8:1.

[0011] In combination with the first aspect, the present invention is further configured as follows: in step S1, the mesh size of the wear-resistant filler is 80 to 3000 meshes.

[0012] In combination with the first aspect, the present invention is further configured as follows: in step S1, the wear-resistant filler is a mixture of one or more of flake graphite, ultra-high molecular weight polyethylene, talcum powder, silicon carbide, corundum powder, zirconium oxide, boron nitride, molybdenum disulfide, and diamond, and the molecular weight of the ultra-high molecular weight polyethylene is 1 million to 10 million.

[0013] In combination with the first aspect, the present invention is further configured as follows: in step S1, the epoxy resin curing agent is one of dipentaerythritol hexa(3-mercaptopropionate) ester and meta-xylylenediamine, or a mixture of the two.

[0014] In combination with the first aspect, the present invention is further configured as follows: in step S2, the defoaming agent is a silicone defoaming agent.

[0015] In combination with the first aspect, the present invention is further configured as follows: in step S2, the epoxy resin monomer is 4,4'-methylbis(N,N-diglycidylaniline).

[0016] In combination with the first aspect, the present invention is further configured as follows: in step S2, the epoxy resin diluent is a mixture of one or more of monoepoxy acryl glycidyl ether, phenyl glycidyl ether, and diepoxy ethylene glycol bisglycidyl ether.

[0017] In combination with the first aspect, the present invention is further configured as follows: in steps S1 and S2, the vacuum degree of the vacuum stirring is -0.1 MPa to -0.09 MPa.

[0018] In combination with the first aspect, the present invention is further configured as follows: in step S3, the vacuum low-temperature stirring temperature is -20 to 0°C, and the stirring time is 0.5h; the initial solidification temperature is -20 to 0°C, and the initial solidification time is 12h; the high-temperature solidification temperature is 30 to 60°C, and the solidification time is 12h.

[0019] The second aspect of the present invention also provides a high-hardness and high-wear-resistant epoxy resin composite material, which is prepared by any of the above methods.

[0020] In summary, the present invention has the following beneficial effects: the epoxy resin and curing agent used in the present invention have higher functionality, higher benzene ring content, higher wear resistance of the filler used, and a more optimized curing process is used, which greatly improves the hardness and wear resistance of the composite resin. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a flow chart of the preparation method of the high-hardness and high-wear-resistant epoxy resin composite material of the present invention;

[0022] Figure 2 The molecular structure formula of dipentaerythritol hexa(3-mercaptopropionic acid) ester of the present invention is:

[0023] Figure 3 It is the molecular structure of m-phenylenediamine;

[0024] Figure 4 It is the molecular structure formula of 4,4'-methylbis(N,N-diglycidylaniline);

[0025] Figure 5 is the hardness test of Example 1 of the present invention;

[0026] Figure 6 is the hardness test of the wear resistance test of Examples 1-3 of the present invention;

[0027] Figure 7 The present invention is a diamond wire saw suitable for the wear resistance test. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0029] This embodiment provides a method for preparing a high-hardness and high-wear-resistant epoxy resin composite material. Figure 1 As shown, the preparation method is as follows:

[0030] In order to improve the problems of low hardness and poor wear resistance of existing epoxy resin composite materials, in the first aspect, the present invention provides a method for preparing a high-hardness and high-wear-resistant epoxy resin composite material, firstly providing an epoxy resin modified curing agent, dispersing the wear-resistant filler in the epoxy resin curing agent in proportion, and obtaining the modified epoxy curing agent by vacuum stirring and dispersion.

[0031] The epoxy curing agent is one of dipentaerythritol hexa(3-mercaptopropionic acid) ester (DHM for short) and meta-xylylenediamine (MXDA for short) or a mixture of the two in any ratio, preferably a mixed curing agent of the two. The structures of DHM and MXDA can be referred to in the attached Figure 2 and Figure 3 . It should be noted that DHM is a hexafunctional curing agent and MXDA is a tetrafunctional curing agent. DHM is a thiol curing agent and MXDA is an amine curing agent. DHM has a higher viscosity than MXDA, and has a higher curing reaction activity with epoxy and a more intense reaction. Depending on the specific conditions, XMDA can be used as a viscosity regulator for DHM and a accelerator for the reaction between DHM and epoxy resin. MXDA is a multifunctional epoxy curing agent containing a benzene ring, which can effectively improve the hardness of epoxy resin composite materials.

[0032] In some specific embodiments, the wear-resistant filler is one or more of flake graphite, ultra-high molecular weight polyethylene, talcum powder, silicon carbide, corundum powder, zirconium oxide, boron nitride, molybdenum disulfide, and diamond mixed in any proportion. The mesh size of the wear-resistant filler is 80 to 3000 meshes.

[0033] In some specific embodiments, the weight average molecular weight of the ultra-high molecular weight polyethylene is 1 million to 10 million. The larger the molecular weight of the ultra-high molecular weight, the stronger the wear resistance, and the better the wear resistance of the composite material.

[0034] In some specific embodiments, the wear-resistant filler and the epoxy resin curing agent are mixed by vacuum stirring, and the vacuum degree is -0.1MPa to -0.09MPa. The vacuum stirring operation can reduce the bubble content in the curing agent, and at the same time avoid the MXDA from being in contact with the air for a long time during the stirring process, absorbing carbon dioxide and water in the air and reacting chemically, causing the MXDA to deteriorate.

[0035] In some specific implementations, the ratio of the wear-resistant filler to the epoxy resin curing agent is 0.1:1 to 0.4:1.

[0036] The invention also provides a modified epoxy resin main agent, which is obtained by mixing an epoxy diluent, a defoamer and the epoxy resin and uniformly mixing them.

[0037] The epoxy resin monomer is 4,4'-methylbis(N,N-diglycidylaniline) (AG80 for short). Compared with traditional epoxy resins such as bisphenol A and bisphenol F, AG80 epoxy resin has a higher functionality of 3.5 to 4. AG resin can greatly improve the hardness, heat resistance, chemical corrosion resistance and other properties of resin composite materials.

[0038] In some specific embodiments, the epoxy resin diluent is one or more of monoepoxy-containing acryl glycidyl ether, phenyl glycidyl ether, and diepoxy-containing ethylene glycol bisglycidyl ether, mixed in any ratio.

[0039] In some specific embodiments, the defoaming agent is a silicone defoaming agent.

[0040] In some specific embodiments, the ratio of the epoxy diluent to the epoxy monomer is 0.05:1 to 0.5:1, and the content of the defoaming agent in the modified epoxy main agent is 0.05% to 1%.

[0041] In some specific embodiments, the epoxy diluent, defoamer and epoxy resin monomer are mixed by vacuum stirring, and the vacuum degree is -0.1 MPa to -0.09 MPa. The vacuum stirring operation can reduce the bubble content in the epoxy main agent.

[0042] The present invention provides an epoxy resin curing method. A modified epoxy main agent and a modified curing agent are mixed in proportion under vacuum and low temperature stirring, and then placed in a low temperature drying oven for initial curing of the system, and then cured at high temperature to obtain a wear-resistant and heat-resistant epoxy resin composite material.

[0043] In some specific embodiments, the vacuum low-temperature stirring temperature is -20 to 0°C, and the stirring time is 0.1 to 0.5 hours. The vacuum environment can reduce the bubbles formed during the mixing and stirring of the curing agent and the main agent, and the low-temperature environment can delay the curing reaction during the stirring and mixing process, so that the curing agent and the main agent are fully mixed and uniform.

[0044] In some specific embodiments, the initial curing temperature is -20 to 0°C, and the initial curing time is 12 hours. Low temperature initial curing can make the DHM component in the curing agent react slowly with the epoxy main agent first, avoiding violent exothermic reaction, ablation, smoking, bubbling and other phenomena.

[0045] In some specific embodiments, the high temperature curing temperature is 30-60° C., and the curing time is 12 hours. High temperature curing can make the XMDA component in the curing agent fully react with the main agent to obtain the target product.

[0046] In some specific implementations, the ratio of the modified epoxy main agent to the modified curing agent is 0.5:1 to 1:1.

[0047] Experimental Materials:

[0048] DHM (purity: ≥93.0%) was purchased from Guangdong Wengjiang Chemical Reagent Co., Ltd.; MXDA (purity: 99.9%) was purchased from Xuzhou Yihuiyang New Materials Co., Ltd.; AG80 (industrial grade) was purchased from Guangzhou Yihuisheng Chemical Co., Ltd.

[0049] Example 1

[0050] Provide epoxy resin modified curing agent. The curing agent uses DHM and MXDA, and the ratio of the two is 1:1. The wear-resistant filler uses ultra-high molecular weight polyethylene with a molecular weight of 5 million. The mass ratio of the wear-resistant filler to the curing agent is 1:6. The modified epoxy curing agent is obtained by vacuum stirring and mixing, the vacuum degree is -0.1Mpa, and the stirring time is 0.5h. Stir and mix at room temperature. The modified epoxy curing agent is obtained.

[0051] Provide epoxy resin modified main agent. AG80 is used as epoxy resin monomer. Polyethylene glycol diglycidyl ether (epoxy diluent 205, content 99%) produced by Xuzhou Yihuiyang New Materials Co., Ltd. is used as epoxy diluent. BYK019 defoamer is used as defoamer. The mass ratio of epoxy diluent to AG80 is 1:9, and the content of defoamer is 0.1%. The epoxy diluent, defoamer and AG80 are mixed, and a modified epoxy main agent is obtained by mixing by vacuum stirring. The vacuum degree is -0.1Mpa, and the stirring time is 1h. Mix by stirring at room temperature. A modified epoxy main agent is obtained.

[0052] Provide epoxy resin composite materials. The modified epoxy main agent and the modified curing agent are mixed in a ratio of 4:5, and after being stirred and mixed evenly under vacuum and low temperature, the system is placed in a low-temperature drying oven for initial solidification, and then high-temperature solidification is performed to obtain a wear-resistant and heat-resistant epoxy resin composite material. The vacuum degree is -0.1Mpa, the stirring time is 0.5h, the stirring temperature is -10℃; the initial solidification temperature, the time is 12h; the high-temperature curing temperature is 60℃, and the curing time is 12h.

[0053] Example 2

[0054] The difference between this embodiment and embodiment 1 is that the ratio of the wear-resistant filler to the curing agent in the curing agent is 2:6.

[0055] Example 3

[0056] The difference between this embodiment and embodiment 1 is that the ratio of the wear-resistant filler to the curing agent in the curing agent is 3:6.

[0057] Comparative Example 1

[0058] The difference between this embodiment and embodiment 1 is that the curing agent is tetra-functional pentaerythritol tetrakis(3-mercaptopropionic acid) ester without benzene ring.

[0059] Comparative Example 2

[0060] The difference between this embodiment and embodiment 1 is that the epoxy monomer adopts a conventional difunctional bisphenol A type epoxy resin monomer.

[0061] Comparative Example 3

[0062] The difference between this embodiment and embodiment 1 is that the wear-resistant filler in the curing agent adopts conventional polyethylene with a molecular weight of 500,000.

[0063] The hardness of the examples and comparative examples was tested by using a Weiden Pointer Shore Hardness Tester (LX-D) to test the hardness of the samples (see Appendix Figure 5 The wear resistance of the samples was tested using a diamond wire saw with a wire diameter of 38 μm, with single crystal silicon as a reference (see Appendix Figure 6 , Attachment Figure 7 The test method is: use a diamond wire saw to cut samples and standard samples of the same size, and use the ratio of the sample cutting depth to the standard silicon cutting depth as the wear resistance evaluation index. The lower the index, the better the wear resistance. The results are shown in Table 1.

[0064] By comparing Example 1 with Comparative Example 1, it can be seen that the use of a high-functionality, high-benzene-ring-content curing agent can improve the hardness of the epoxy resin composite material; by comparing Example 1 with Comparative Example 2, it can be seen that the use of a high-functionality, high-benzene-ring-content epoxy resin monomer can also improve the hardness of the epoxy resin composite material; by comparing Example 1 with Comparative Example 1, it can be seen that a high-functionality, high-benzene-ring-content curing agent can improve the hardness of the epoxy resin composite material; by comparing Example 1 with Comparative Example 3, it can be seen that the use of ultra-high molecular weight polyethylene can increase the wear resistance of the epoxy resin composite material. By comparing Examples 1, 2, and 3, it can be seen that the wear resistance of the epoxy resin composite material increases with the increase in the amount of ultra-high molecular weight added.

[0065] Table 1. Hardness and wear resistance of Examples 1-3 and Comparative Examples 1-3

[0066] Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 <![CDATA[Hardness 1 > 87.5 88 87 75 70 85 <![CDATA[Wear resistance 2 > 1.77 1.31 1.25 1.85 1.95 1.92

[0067] Note: 1 Shao D; 2 The lower the value, the better the wear resistance.

[0068] Example 4

[0069] This embodiment provides a method for preparing a high-hardness and high-wear-resistant epoxy resin composite material, and the preparation method is as follows:

[0070] Provide epoxy resin modified curing agent. The curing agent uses DHM and MXDA, and the ratio of the two is 1:1. The wear-resistant filler uses 1000 mesh flake graphite. The ratio of the wear-resistant filler to the curing agent is 1:6. The modified epoxy curing agent is obtained by vacuum stirring and mixing, the vacuum degree is -0.1Mpa, and the stirring time is 0.5h. Stir and mix at room temperature. The modified epoxy curing agent is obtained.

[0071] Provide epoxy resin modified main agent. AG80 is used as epoxy resin monomer. Polyethylene glycol diglycidyl ether (epoxy diluent 205, content 99%) produced by Xuzhou Yihuiyang New Materials Co., Ltd. is used as epoxy diluent. BYK019 defoamer is used as defoamer. The ratio of epoxy diluent to AG80 is 1:9, and the content of defoamer is 0.1%. Mix the epoxy diluent, defoamer and AG80, and obtain a modified epoxy main agent by vacuum stirring. The vacuum degree is -0.1Mpa, and the stirring time is 1h. Stir and mix at room temperature. Obtain a modified epoxy main agent.

[0072] Provide epoxy resin composite materials. The modified epoxy main agent and the modified curing agent are mixed in a ratio of 4:5, and after being stirred and mixed evenly under vacuum and low temperature, the system is placed in a low-temperature drying oven for initial solidification, and then high-temperature solidification is performed to obtain a wear-resistant and heat-resistant epoxy resin composite material. The vacuum degree is -0.1Mpa, the stirring time is 0.5h, the stirring temperature is -10℃; the initial solidification temperature, the time is 12h; the high-temperature curing temperature is 60℃, and the curing time is 12h.

[0073] Example 5

[0074] This embodiment is basically the same as Embodiment 4, except that the ratio of the wear-resistant filler to the curing agent in the curing agent is 2:6.

[0075] Example 6

[0076] This embodiment is basically the same as Embodiment 4, except that the ratio of the wear-resistant filler to the curing agent in the curing agent is 3:6.

[0077] The hardness and wear resistance test results are shown in Table 2.

[0078] By comparing Example 4 with Example 1, it can be seen that the use of flake graphite can increase the wear resistance of the epoxy resin composite material. By comparing Examples 4, 5, and 6, it can be seen that the wear resistance of the epoxy resin composite material increases with the increase in the amount of flake graphite added.

[0079] Table 2. Hardness and wear resistance of Examples 4-6

[0080] Example 4 Example 5 Example 6 hardness 85 87 89 Wear resistance 1.09 0.93 0.74

[0081] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a high-hardness and high-wear-resistant epoxy resin composite material, characterized in that: The steps include: S1. The wear-resistant filler is dispersed in the epoxy resin curing agent in proportion, and the modified epoxy curing agent is obtained by vacuum stirring and mixing, wherein the mass ratio of the wear-resistant filler to the epoxy resin curing agent is 0.17:1 to 0.5:1; S2. The epoxy diluent, the defoamer and the epoxy resin monomer are mixed, and the modified epoxy main agent is obtained by mixing by vacuum stirring, the mass ratio of the epoxy diluent to the epoxy main agent is 1:9, and the content of the defoamer in the modified epoxy main agent is 0.1%; S3. After the modified epoxy main agent and the modified curing agent are mixed evenly in proportion by vacuum low-temperature stirring, the system is placed in a low-temperature drying oven for initial curing, and then cured at high temperature to obtain a wear-resistant and heat-resistant epoxy resin composite material; the mass ratio of the modified epoxy main agent to the modified curing agent is 0.8:

1.

2. The method for preparing a high-hardness and high-wear-resistant epoxy resin composite material according to claim 1, characterized in that: In step S1, the mesh size of the wear-resistant filler is 80 to 3000 meshes.

3. The method for preparing a high-hardness and high-wear-resistant epoxy resin composite material according to claim 1, characterized in that: In step S1, the wear-resistant filler is a mixture of one or more of flake graphite, ultra-high molecular weight polyethylene, talcum powder, silicon carbide, corundum powder, zirconium oxide, boron nitride, molybdenum disulfide, and diamond, and the molecular weight of the ultra-high molecular weight polyethylene is 1 million to 10 million.

4. The method for preparing a high-hardness and high-wear-resistant epoxy resin composite material according to claim 1, characterized in that: In step S1, the epoxy resin curing agent is one of dipentaerythritol hexa(3-mercaptopropionate) ester and meta-xylylenediamine or a mixture of the two.

5. The method for preparing a high-hardness and high-wear-resistant epoxy resin composite material according to claim 1, characterized in that: In step S2, the defoaming agent is a silicone defoaming agent.

6. The method for preparing a high-hardness and high-wear-resistant epoxy resin composite material according to claim 1, characterized in that: In step S2, the epoxy resin monomer is 4,4'-methylbis(N,N-diglycidylaniline).

7. The method for preparing a high-hardness and high-wear-resistant epoxy resin composite material according to claim 1, characterized in that: In step S2, the epoxy resin diluent is a mixture of one or more of monoepoxy-containing acryl glycidyl ether, phenyl glycidyl ether, and diepoxy-containing ethylene glycol bisglycidyl ether.

8. The method for preparing a high-hardness and high-wear-resistant epoxy resin composite material according to claim 1, characterized in that: In steps S1 and S2, the vacuum degree of the vacuum stirring is -0.1 MPa to -0.09 MPa.

9. The method for preparing a high-hardness and high-wear-resistant epoxy resin composite material according to claim 1, characterized in that: In step S3, the vacuum low-temperature stirring temperature is -20 to 0°C, and the stirring time is 0.5h; the initial solidification temperature is -20 to 0°C, and the initial solidification time is 12h; the high-temperature solidification temperature is 30 to 60°C, and the solidification time is 12h.

10. A high-hardness and high-wear-resistant epoxy resin composite material, characterized by: The invention is manufactured by the method described in any one of claims 1 to 9.

Images