A basalt fiber reinforced epoxy resin composite material and electronic equipment housing

Abstract

The present invention proposes a basalt fiber reinforced epoxy resin composite material and an electronic device housing, wherein the composite material is made of basalt fiber cloth and epoxy resin glue; wherein the weight proportion of the basalt fiber cloth is 45-75wt%, and the weight proportion of the epoxy resin glue is 25-55wt%; the basalt fiber cloth is epoxy-modified basalt fiber cloth, and the epoxy resin glue is graphene-modified epoxy resin glue. The present invention proposes a basalt fiber reinforced epoxy resin composite material and an electronic device housing, wherein the composite material has both high mechanical strength and high interface toughness, and can be widely used in electronic device housings.

Description

Technical Field

[0001] The invention relates to the technical field of composite materials, and in particular to a basalt fiber reinforced epoxy resin composite material and an electronic equipment housing. Background Art

[0002] Usually, the shell of consumer electronic products such as mobile phones and tablets is a plastic or metal structure, and the overall mass of the shell is heavy. In order to balance the deficiencies in quality and strength, some products will combine metal and plastic materials, use metal in some supporting structural parts, and use plastic in areas with lower force requirements, but these improvements cannot maximize the mechanical properties required by product design. For this reason, people have turned their attention to fiber composite reinforced materials with better structural strength and lighter weight, among which carbon fiber composite reinforced materials have become a hot topic of concern. Carbon fiber materials show high strength along the fiber axis, and the specific gravity of carbon fiber is small, with high specific strength. The specific gravity of carbon fiber is less than 1 / 4 of that of steel, and the tensile strength is generally above 3500MPa, which is 7-9 times that of steel. The tensile elastic modulus is also higher than that of steel, which is 23000-43000MPa. Its material strength-to-density ratio can reach 2000MPa (g / cm 3 ), while the specific strength of A3 steel is only 59MPa / (g / cm 3 )about.

[0003] The existing preparation process of carbon fiber electronic product shells mainly includes: using 3k carbon fiber to weave fiber cloth, then impregnating or coating it with resin, hot pressing the fiber cloth impregnated or coated with resin, shearing the molded product, and then using injection molding to form functional components, thereby obtaining a shell with application functions, but the disadvantage of carbon fiber is its high cost.

[0004] Basalt fiber (BF) is made of natural volcanic rock as raw material. It is crushed and added to the melting furnace. After melting at 1450-1500℃, it is drawn through a platinum-rhodium alloy plate. The main components are SiO2, Fe2O3 and Al2O3. The tensile strength of basalt fiber is higher than that of E-glass fiber and slightly lower than that of S-glass fiber. It is similar to the performance of ordinary carbon fiber. Due to its wide source, the production cost is much lower than that of carbon fiber. At the same time, compared with the disadvantage of other high-performance fibers releasing toxic substances, corrosive substances and pollutants during the production process, no pollutants are produced during the production process of basalt fiber, and it is considered to be a green and pollution-free high-performance fiber. In addition, basalt fiber also has many advantages such as good corrosion resistance, excellent high temperature resistance, chemical stability, electrical insulation, etc. It is an inorganic fiber with excellent comprehensive performance and extremely high cost performance. It is widely used to reinforce epoxy resin-based composite materials.

[0005] In view of the above characteristics, basalt fiber has great application potential in the structural, construction, thermal insulation, automotive and other industries, and is also an excellent fiber reinforcement phase choice for reinforced composite materials. However, its smooth surface morphology and chemical inertness make it difficult to bond with the polymer matrix, limiting its use as a reinforcing material. Summary of the invention

[0006] Based on the technical problems existing in the background technology, the present invention proposes a basalt fiber reinforced epoxy resin composite material and an electronic equipment housing. The composite material has both high mechanical strength and high interface toughness and can be widely used in electronic equipment housings.

[0007] The present invention provides a basalt fiber reinforced epoxy resin composite material, wherein the composite material is made of basalt fiber cloth and epoxy resin adhesive; wherein the weight proportion of the basalt fiber cloth is 45-75wt%, and the weight proportion of the epoxy resin adhesive is 25-55wt%;

[0008] The basalt fiber cloth is epoxy-modified basalt fiber cloth, and the epoxy resin glue is graphene-modified epoxy resin glue.

[0009] Preferably, the epoxy-modified basalt fiber cloth is prepared by immersing the basalt fiber cloth in a solution containing an isocyanate silane coupling agent, heating the solution for reaction, and then reacting the solution with glycidol to obtain the epoxy-modified basalt fiber cloth.

[0010] Preferably, the isocyanate-containing silane coupling agent is at least one of isocyanate propyl trimethoxy silane, isocyanate propyl triethoxy silane, isocyanate methyl trimethoxy silane or isocyanate methyl triethoxy silane.

[0011] Preferably, the surface density of the basalt fiber cloth is 100-500g / m 2 .

[0012] Preferably, the graphene-modified epoxy resin adhesive is obtained by mixing amination graphene with epoxy resin and curing agent.

[0013] Preferably, the epoxy resin is at least one of bisphenol A epoxy resin, bisphenol F epoxy resin or phenolic epoxy resin, and the curing agent is at least one of amine curing agent or acid anhydride curing agent.

[0014] Preferably, the weight ratio of the amino graphene, epoxy resin and curing agent is 1-5:100:5-25.

[0015] The present invention also provides a method for preparing the above basalt fiber reinforced epoxy resin composite material, comprising the following steps:

[0016] S1, coating the surface of epoxy-modified basalt fiber cloth with graphene-modified epoxy resin glue to obtain pre-impregnated basalt fiber cloth;

[0017] S2, stacking the pre-impregnated basalt fiber cloth, and heating and molding it to obtain the basalt fiber reinforced epoxy resin composite material.

[0018] Preferably, the heating molding is performed at a temperature of 120-150° C., a time of 2-5 h, and a pressure of 1-5 MPa.

[0019] The present invention also provides an electronic equipment housing, which is composed of the above-mentioned basalt fiber reinforced epoxy resin composite material.

[0020] In the present invention, in order to improve the adhesion between the basalt fiber cloth and the epoxy resin glue, the basalt fiber cloth is first impregnated with an isocyanate silane coupling agent solution before being coated with the epoxy resin glue, so that the isocyanate group is grafted on the surface of the basalt fiber cloth, and then reacted with glycidol to graft the epoxy group on the surface of the basalt fiber cloth, and then coated with a resin glue containing epoxy resin, amino graphene and a curing agent. Since there is good compatibility between the epoxy resin and the epoxy group, the epoxy resin can be effectively attached to the surface of the basalt fiber cloth. In this way, when the epoxy resin is subsequently cured, the epoxy group introduced on the basalt fiber cloth can enhance its binding ability with the epoxy resin and the effect of chain entanglement, further improve the interface performance, and make the formed cured resin glue layer firmly attached to the surface of the basalt fiber cloth, so that the mechanical intercalation between the basalt fiber fabric and the epoxy resin is enhanced, and the interface strength of the basalt fiber plant is further enhanced without affecting the fiber strength performance, which is helpful for use in electronic equipment housings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the structure of the epoxy-modified basalt fiber cloth according to an embodiment of the present invention. DETAILED DESCRIPTION

[0022] The technical solutions of the present invention are described in detail below through specific embodiments. However, it should be clearly stated that these embodiments are for illustration only and are not to be construed as limiting the scope of the present invention.

[0023] Example 1

[0024] A basalt fiber reinforced epoxy resin composite material, the preparation method of which comprises the following steps:

[0025] (1) Basalt fiber cloth (surface density 225g / m 2) is added to acetone and soaked for 12 hours, taken out and dried, then added to an ethanol-water (volume ratio of 1:1) solution of 3-isocyanate propyl triethoxysilane with a concentration of 5wt% and immersed for 2 hours, taken out, and heated at 110°C for 2 hours to obtain an isocyanate-modified basalt fiber cloth; the isocyanate-modified basalt fiber cloth is then added to an acetone solution of 3wt% glycidol, heated to 60°C and soaked for 12 hours, taken out and dried to obtain an epoxy-modified basalt fiber cloth;

[0026] (2) natural graphite powder (particle size of 300 mesh) was prepared by the classic Hunmers method to obtain graphene oxide, and then the graphene oxide was added to nitrogen methyl pyrrolidone for ultrasonic dispersion for 2 hours, and then 10 wt% of ethylenediamine by weight of graphene oxide was added, and the mixture was stirred at 80° C. for 4 hours, filtered, and dried to obtain amino graphene;

[0027] (3) Stirring the bisphenol A epoxy resin (E-51) at 60° C. for 0.5 h, adding 3 wt % of the amino graphene by weight of the bisphenol A epoxy resin (E-51) and 16 wt % of the methyltetrahydrophthalic anhydride by weight of the bisphenol A epoxy resin (E-51), stirring and mixing, and obtaining a graphene-modified epoxy resin glue;

[0028] (4) coating the graphene-modified epoxy resin adhesive on a polyester release film, laying the epoxy-modified basalt fiber cloth on top, placing another layer of polyester release film on top, and entering a laminating machine for multiple rolling to obtain a pre-impregnated basalt fiber cloth, wherein the weight proportion of the graphene-modified epoxy resin adhesive is 37wt%;

[0029] (5) Ten layers of the above-mentioned pre-impregnated basalt fiber cloth are stacked and laid, placed in a hot press for hot pressing, pre-cured for 0.5 h, the pressure is increased to 1 MPa, the temperature is increased to 120°C, cured for 1 h, then the pressure is increased to 3 MPa, the temperature is increased to 150°C, cured for 1 h, the pressure is increased to 5 MPa, cured for 1 h, taken out and cooled to room temperature, to obtain the basalt fiber reinforced epoxy resin composite material.

[0030] Example 2

[0031] A basalt fiber reinforced epoxy resin composite material, the preparation method of which comprises the following steps:

[0032] (1) Prepare epoxy-modified basalt fiber cloth according to the method described in Example 1;

[0033] (2) preparing amino graphene according to the method described in Example 1;

[0034] (3) Stirring the bisphenol A epoxy resin (E-51) at 60° C. for 0.5 h, adding 1 wt % of amino graphene based on the mass of the bisphenol A epoxy resin (E-51) and 10 wt % of methyltetrahydrophthalic anhydride based on the mass of the bisphenol A epoxy resin (E-51), stirring and mixing, and obtaining a graphene-modified epoxy resin glue;

[0035] (4) coating the graphene-modified epoxy resin adhesive on a polyester release film, laying the epoxy-modified basalt fiber cloth on top, placing another layer of polyester release film on top, and entering a laminating machine for multiple rolling to obtain a pre-impregnated basalt fiber cloth, wherein the weight proportion of the graphene-modified epoxy resin adhesive is 25wt%;

[0036] (5) Ten layers of the above-mentioned pre-impregnated basalt fiber cloth are stacked and laid, placed in a hot press for hot pressing, pre-cured for 0.5 h, the pressure is increased to 1 MPa, the temperature is increased to 120°C, cured for 1 h, then the pressure is increased to 3 MPa, the temperature is increased to 150°C, cured for 1 h, the pressure is increased to 5 MPa, cured for 1 h, taken out and cooled to room temperature, to obtain the basalt fiber reinforced epoxy resin composite material.

[0037] Example 3

[0038] A basalt fiber reinforced epoxy resin composite material, the preparation method of which comprises the following steps:

[0039] (1) Prepare epoxy-modified basalt fiber cloth according to the method described in Example 1;

[0040] (2) preparing amino graphene according to the method described in Example 1;

[0041] (3) Stirring the bisphenol A epoxy resin (E-51) at 60° C. for 0.5 h, adding 5 wt% of the amino graphene by weight of the bisphenol A epoxy resin (E-51) and 20 wt% of the methyltetrahydrophthalic anhydride by weight of the bisphenol A epoxy resin (E-51), stirring and mixing, and obtaining a graphene-modified epoxy resin glue;

[0042] (4) coating the graphene-modified epoxy resin adhesive on a polyester release film, laying the epoxy-modified basalt fiber cloth on top, placing another layer of polyester release film on top, and entering a laminating machine for multiple rolling to obtain a pre-impregnated basalt fiber cloth, wherein the weight proportion of the graphene-modified epoxy resin adhesive is 55wt%;

[0043] (5) Ten layers of the above-mentioned pre-impregnated basalt fiber cloth are stacked and laid, placed in a hot press for hot pressing, pre-cured for 0.5 h, the pressure is increased to 1 MPa, the temperature is increased to 120°C, cured for 1 h, then the pressure is increased to 3 MPa, the temperature is increased to 150°C, cured for 1 h, the pressure is increased to 5 MPa, cured for 1 h, taken out and cooled to room temperature, to obtain the basalt fiber reinforced epoxy resin composite material.

[0044] Comparative Example 1

[0045] A basalt fiber reinforced epoxy resin composite material, the preparation method of which comprises the following steps:

[0046] (1) natural graphite powder (particle size of 300 mesh) was prepared by the classic Hunmers method to obtain graphene oxide, and then the graphene oxide was added to nitrogen methyl pyrrolidone for ultrasonic dispersion for 2 hours, and then 10 wt% of ethylenediamine by weight of the graphene oxide was added, and the mixture was stirred at 80° C. for 4 hours, filtered, and dried to obtain amino graphene;

[0047] (2) stirring the bisphenol A epoxy resin (E-51) at 60° C. for 0.5 h, adding 3 wt % of the amino graphene by weight of the bisphenol A epoxy resin (E-51) and 16 wt % of the methyltetrahydrophthalic anhydride by weight of the bisphenol A epoxy resin (E-51), stirring and mixing, and obtaining a graphene-modified epoxy resin glue;

[0048] (3) The graphene-modified epoxy resin adhesive was coated on a polyester release film, and a basalt fiber cloth (surface density of 225 g / m 2 ), a layer of polyester release film is placed on top, and the pre-impregnated basalt fiber cloth is obtained by multiple rolling in a laminating machine, wherein the weight proportion of the graphene-modified epoxy resin adhesive is 37wt%;

[0049] (4) Ten layers of the above-mentioned pre-impregnated basalt fiber cloth are stacked and laid, placed in a hot press for hot pressing, pre-cured for 0.5 h, the pressure is increased to 1 MPa, the temperature is increased to 120°C, cured for 1 h, then the pressure is increased to 3 MPa, the temperature is increased to 150°C, cured for 1 h, the pressure is increased to 5 MPa, cured for 1 h, taken out and cooled to room temperature, to obtain the basalt fiber reinforced epoxy resin composite material.

[0050] Comparative Example 2

[0051] A basalt fiber reinforced epoxy resin composite material, the preparation method of which comprises the following steps:

[0052] (1) Basalt fiber cloth (surface density 225g / m 2) was added to acetone and soaked for 12 hours, taken out and dried, and then added to an ethanol-water (volume ratio of 1:1) solution of 3-isocyanatepropyltriethoxysilane with a concentration of 5wt% and immersed for 2 hours, and then taken out and heated at 110°C for 2 hours to obtain an isocyanate-modified basalt fiber cloth;

[0053] (2) natural graphite powder (particle size of 300 mesh) was prepared by the classic Hunmers method to obtain graphene oxide, and then the graphene oxide was added to nitrogen methyl pyrrolidone for ultrasonic dispersion for 2 hours, and then 10 wt% of ethylenediamine by weight of the graphene oxide was added, and the mixture was stirred at 80° C. for 4 hours, filtered, and dried to obtain amino graphene;

[0054] (3) Stirring the bisphenol A epoxy resin (E-51) at 60° C. for 0.5 h, adding 3 wt % of the amino graphene by weight of the bisphenol A epoxy resin (E-51) and 16 wt % of the methyltetrahydrophthalic anhydride by weight of the bisphenol A epoxy resin (E-51), stirring and mixing, and obtaining a graphene-modified epoxy resin glue;

[0055] (4) coating the graphene-modified epoxy resin adhesive on a polyester release film, laying the isocyanate-modified basalt fiber cloth on top, placing another layer of polyester release film on top, and entering a laminating machine for multiple rolling to obtain a pre-impregnated basalt fiber cloth, wherein the weight proportion of the graphene-modified epoxy resin adhesive is 37wt%;

[0056] (5) Ten layers of the above-mentioned pre-impregnated basalt fiber cloth are stacked and laid, placed in a hot press for hot pressing, pre-cured for 0.5 h, the pressure is increased to 1 MPa, the temperature is increased to 120°C, cured for 1 h, then the pressure is increased to 3 MPa, the temperature is increased to 150°C, cured for 1 h, the pressure is increased to 5 MPa, cured for 1 h, taken out and cooled to room temperature, to obtain the basalt fiber reinforced epoxy resin composite material.

[0057] Comparative Example 3

[0058] A basalt fiber reinforced epoxy resin composite material, the preparation method of which comprises the following steps:

[0059] (1) Basalt fiber cloth (surface density 225g / m 2 ) is added to acetone and soaked for 12 hours, taken out and dried, then added to an ethanol-water (volume ratio of 1:1) solution of 3-isocyanate propyl triethoxysilane with a concentration of 5wt% and immersed for 2 hours, taken out, and heated at 110°C for 2 hours to obtain an isocyanate-modified basalt fiber cloth; the isocyanate-modified basalt fiber cloth is then added to an acetone solution of 3wt% glycidol, heated to 60°C and soaked for 12 hours, taken out and dried to obtain an epoxy-modified basalt fiber cloth;

[0060] (2) Stirring the bisphenol A epoxy resin (E-51) at 60° C. for 0.5 h, adding 16 wt % of methyltetrahydrophthalic anhydride based on the mass of the bisphenol A epoxy resin (E-51), stirring and mixing, and obtaining epoxy resin glue;

[0061] (4) coating the epoxy resin glue on a polyester release film, laying the epoxy-modified basalt fiber cloth on top, placing another layer of polyester release film on top, and entering a laminating machine for multiple rolling to obtain a pre-impregnated basalt fiber cloth, wherein the weight of the epoxy resin glue accounts for 37wt%;

[0062] (5) Ten layers of the above-mentioned pre-impregnated basalt fiber cloth are stacked and laid, placed in a hot press for hot pressing, pre-cured for 0.5 h, the pressure is increased to 1 MPa, the temperature is increased to 120°C, cured for 1 h, then the pressure is increased to 3 MPa, the temperature is increased to 150°C, cured for 1 h, the pressure is increased to 5 MPa, cured for 1 h, taken out and cooled to room temperature, to obtain the basalt fiber reinforced epoxy resin composite material.

[0063] The tensile strength, flexural strength and interlaminar shear strength of the basalt fiber reinforced epoxy resin composite materials described in the examples and comparative examples were tested according to GB / T1447, GB / T1449 and JC / T773 standards. The results are shown in Table 1 below.

[0064] Table 1 Performance test results of the epoxy resin composite materials described in Examples and Comparative Examples

[0065]

[0066] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A basalt fiber reinforced epoxy resin composite material, characterized in that: The composite material is made of basalt fiber cloth and epoxy resin glue; wherein the weight of the basalt fiber cloth accounts for 45-75wt%, and the weight of the epoxy resin glue accounts for 25-55wt%; The basalt fiber cloth is epoxy-modified basalt fiber cloth, and the epoxy resin glue is graphene-modified epoxy resin glue.

2. The basalt fiber reinforced epoxy resin composite material according to claim 1, characterized in that: The epoxy-modified basalt fiber cloth is prepared by immersing the basalt fiber cloth in a solution containing an isocyanate silane coupling agent, heating the solution for reaction, and then reacting the solution with glycidol to obtain the epoxy-modified basalt fiber cloth.

3. The basalt fiber reinforced epoxy resin composite material according to claim 2, characterized in that: The isocyanate-containing silane coupling agent is at least one of isocyanate propyl trimethoxy silane, isocyanate propyl triethoxy silane, isocyanate methyl trimethoxy silane or isocyanate methyl triethoxy silane.

4. The basalt fiber reinforced epoxy resin composite material according to claim 2 or 3, characterized in that: The surface density of the basalt fiber cloth is 100-500g / m 2 .

5. The basalt fiber reinforced epoxy resin composite material according to any one of claims 1 to 4, characterized in that: The graphene-modified epoxy resin adhesive is obtained by uniformly mixing amination graphene, epoxy resin and curing agent.

6. The basalt fiber reinforced epoxy resin composite material according to claim 5, characterized in that: The epoxy resin is at least one of bisphenol A epoxy resin, bisphenol F epoxy resin or phenolic epoxy resin, and the curing agent is at least one of amine curing agent or acid anhydride curing agent.

7. The basalt fiber reinforced epoxy resin composite material according to claim 5 or 6, characterized in that: The weight ratio of the amino graphene, epoxy resin and curing agent is 1-5:100:5-25.

8. A method for preparing the basalt fiber reinforced epoxy resin composite material according to any one of claims 1 to 7, characterized in that: The steps include: S1, coating the surface of epoxy-modified basalt fiber cloth with graphene-modified epoxy resin glue to obtain pre-impregnated basalt fiber cloth; S2, stacking the pre-impregnated basalt fiber cloth, and heating and molding it to obtain the basalt fiber reinforced epoxy resin composite material.

9. The method for preparing the basalt fiber reinforced epoxy resin composite material according to claim 8, characterized in that: The heating molding is performed at a temperature of 120-150° C., a time of 2-5 hours, and a pressure of 1-5 MPa.

10. An electronic device housing, characterized in that: The invention is composed of the basalt fiber reinforced epoxy resin composite material as described in any one of claims 1 to 7.

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