Flame-retardant SMC (Sheet Molding Compound) composite material capable of being rapidly formed and preparation method

Abstract

The invention discloses a flame-retardant SMC composite material capable of being rapidly formed, the flame-retardant SMC composite material comprises, by weight, 30-50 parts of chopped fibers and 50-70 parts of a resin matrix, and the resin matrix comprises, by weight, 65-80 parts of liquid epoxy resin, 5-15 parts of a diluent, 5-15 parts of a curing agent, 0.5-3 parts of an internal release agent, 6-15 parts of a thickener, 0.3-1 part of a wetting agent and 2-5 parts of a flame-retardant curing agent. 5-30 parts of a flame retardant (powder) and 5-15 parts of a smoke suppressant (powder); the chopped fibers comprise carbon fibers, glass fibers, aramid fibers and the like. The flame retardant property of the SMC composite material can reach V-0 level, and the apparent property and physical property of subsequent parts are excellent.

Description

Technical Field

[0001] The present invention relates to the field of SMC materials, and particularly relates to a flame-retardant SMC that can be rapidly formed with low powder content and a preparation method thereof. Background Art

[0002] SMC (Sheet molding compound) refers to sheet molding compound, which is mainly a type of sheet molding compound made by impregnating chopped fibers with resin paste and is an intermediate material for composite materials. This material is convenient to use and is cured at high temperature through forming processes such as compression molding process and autoclave process. As the application fields of SMC become more and more extensive, more requirements are put forward for the functions of SMC, such as flame retardancy. At present, there are a large amount of resins in SMC itself, and most of the resins are flammable. Therefore, it is difficult for conventional SMC materials to meet the flame retardant requirements. Currently, to improve the flame retardant performance of SMC, usually a large amount of non-reactive powder flame retardant is added to the resin, but the increase in powder will reduce the wetting effect of the resin on the fibers, and there will be more apparent defects and material mechanical property defects after the SMC material is formed into a product. There is also the use of liquid flame retardants in the resin to reduce the powder addition, but the use of conventional liquid flame retardants will prolong the resin curing time, extend the material forming cycle, increase the processing cost, and there is a risk of precipitation of the flame retardant after curing, polluting the environment. Summary of the Invention

[0003] In view of this, the present invention provides a flame-retardant SMC composite material that can be rapidly formed and a preparation method thereof to solve the defects that existing flame-retardant SMC or powder affects the material performance or the forming time is long.

[0004] In the first aspect, a flame-retardant SMC composite material that can be rapidly formed is provided. By weight, it includes: 30 - 50 parts of chopped fibers and 50 - 70 parts of resin matrix.

[0005] The resin matrix, by weight, includes: 65 - 80 parts of liquid epoxy resin, 5 - 15 parts of diluent, 5 - 15 parts of curing agent, 0.5 - 3 parts of internal mold release agent, 6 - 15 parts of thickening agent, 0.3 - 1 part of wetting agent, 2 - 5 parts of flame-retardant curing agent, 5 - 30 parts (powder) of flame retardant, and 5 - 15 parts (powder) of smoke suppressant.

[0006] The chopped fibers include carbon fiber, glass fiber, aramid fiber, etc.

[0007] The preparation method of the flame-retardant curing agent, by weight of raw materials, includes: Step 1: Add 100 parts of 9,10-dihydro-9-oxa-10-phosphaphenanthrene to 500 parts of absolute ethanol, heat to 50 - 60 °C, and stir to dissolve to obtain a 9,10-dihydro-9-oxa-10-phosphaphenanthrene solution; Step 2: Add 120 parts of hydrogen peroxide to the 9,10-dihydro-9-oxa-10-phosphaphenanthrene solution obtained in Step 1, heat up to 70 - 80 °C, react for 5 hours, evaporate ethanol, and filter to obtain a white powder; Step 3: Rinse the white powder obtained in Step 3 with acetone, dry it after rinsing to obtain DOPA; Step 4: Mix DOPA, 1-propylimidazole, phosphorous acid, and absolute ethanol in a weight ratio of 5:10:2:60, heat up to 60 - 70 °C, stir and react for 1 - 2 hours, evaporate ethanol to obtain a flame retardant curing agent.

[0008] The flame retardant should include one or more of aluminum diethylphosphinate, ammonium polyphosphate, piperazine pyrophosphate, and melamine cyanurate.

[0009] The smoke suppressant should include one or more of zinc borate, zinc stannate, and ammonium octamolybdate.

[0010] The epoxy resin should include one or more of liquid bisphenol A epoxy resin, liquid bisphenol F epoxy resin, liquid multi-functional epoxy resin, and liquid phenolic epoxy resin.

[0011] The diluent should include one or more of 1,4-cyclohexanedimethanol diglycidyl ether and resorcinol diglycidyl ether.

[0012] The curing agent should include one or more of dicyandiamide fine powder, bis(4-aminophenyl)sulfone, and 4,4'-diaminodiphenylmethane.

[0013] The internal mold release agent should include one or more of ACMOSAL 82 - 869, BYK-P 9080, and BYK-P 9912.

[0014] The thickening agent should include one or more of 1,3-cyclohexanediamine, 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane, and isophorone diamine.

[0015] The wetting agent should include one or more of BYK-9076, BYK-W 9010, and UNIQSPERSE P-193.

[0016] In a second aspect, the present invention also provides a preparation method of a flame retardant SMC composite material capable of rapid prototyping, including the steps: S1. Weighing: Weigh 65 - 80 parts of liquid epoxy resin, 5 - 15 parts of diluent, 5 - 15 parts of curing agent, 0.5 - 3 parts of internal mold release agent, 10 - 15 parts of thickening agent, 0.3 - 1 part of wetting agent, 2 - 5 parts of flame retardant curing agent, 5 - 30 parts of flame retardant, and 5 - 15 parts of smoke suppressant according to the resin matrix raw material ratio.

[0017] S2. Disperse liquid epoxy resin, flame retardant, and smoke suppressant using a high-speed disperser until there is no agglomeration; S3. Add a flame retardant curing agent to the mixture obtained in S2 and mix thoroughly until evenly distributed; S4. Add a diluent, internal mold release agent, and wetting agent to the mixture obtained in S3 and mix thoroughly until evenly distributed; S5. Add a curing agent to the mixture obtained in S4 and disperse until there is no agglomeration; S6. Add a thickening agent to the mixture obtained in S5 and mix evenly to obtain a resin matrix; S7. Coat the resin matrix on a carrier film, compound it with chopped fibers to form a sheet, and after thickening, an SMC composite material can be obtained.

[0018] In this solution, a flame retardant curing agent is used, thereby reducing the addition amount of conventional flame retardant powder, solving the problem of excessive powder and the risk of agglomeration and precipitation in the prior art. At the same time, the fiber wettability is improved, and subsequent product defects are reduced. Due to the use of a flame retardant curing agent, its reaction temperature is relatively low, which easily causes premature curing of the resin and produces flocculent precipitation. Therefore, in this solution, by adjusting the addition sequence of raw materials, the resin, flame retardant, and smoke suppressant are first mixed. The flame retardant and smoke suppressant have a certain inhibitory effect on the curing of the resin, solving the problem of flocculent precipitation caused by premature curing of the resin during the preparation of the resin mixture.

[0019] The beneficial effects of the present invention are at least as follows: (1) In the present invention, on the premise of meeting the flame retardant performance requirements, the amount of powder flame retardant used to enhance the flame retardant performance is reduced, avoiding the risk of powder agglomeration and precipitation. The flame retardant curing agent molecules can be incorporated into the cross-linked network of the resin, enhancing the flame retardant performance of the material without the risk of precipitation; (2) At the same time, the low-powder resin mixture infiltrates the fibers more fully, reducing the probability of defects in subsequent SMC products; (3) After using the flame retardant curing agent, it will not extend the resin curing time, so it will not extend the material molding cycle. Specific embodiments

[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention. Example 1

[0021] A flame-retardant SMC composite material capable of rapid prototyping, calculated by weight parts of raw materials, comprising 30-50 parts of chopped fibers and 50-70 parts of resin matrix; The resin matrix, calculated by weight parts of raw materials, includes: 40 parts of liquid bisphenol A epoxy resin; 20 parts of liquid phenolic epoxy resin; 13 parts of liquid multi-functional epoxy resin; 7 parts of 1,4-cyclohexanedimethanol diglycidyl ether; 7 parts of dicyandiamide fine powder, 2 parts of ACMOSAL 82-869, 0.5 part of BYK-W 9010, 3 parts of flame-retardant curing agent, 10 parts of zinc borate, 20 parts of aluminum diethylphosphinate, 11 parts of isophorone diamine.

[0022] Under this embodiment, the preparation method of the flame-retardant SMC composite material capable of rapid prototyping includes the steps: S1. Raw material weighing: Weigh 40 parts of liquid bisphenol A epoxy resin, 20 parts of liquid phenolic epoxy resin, 13 parts of liquid multi-functional epoxy resin, 7 parts of 1,4-cyclohexanedimethanol diglycidyl ether, 7 parts of dicyandiamide fine powder, 2 parts of ACMOSAL 82-869, 0.5 part of BYK-W 9010, 3 parts of flame-retardant curing agent, 10 parts of zinc borate, 20 parts of aluminum diethylphosphinate, 11 parts of isophorone diamine according to the weight ratio of raw materials; S2. Disperse the liquid bisphenol A epoxy resin, liquid phenolic epoxy resin, liquid multi-functional epoxy resin, aluminum diethylphosphinate and zinc borate with a high-speed disperser until there is no agglomeration; S3. Add the flame-retardant curing agent to the mixture obtained in S2 and mix well; S4. Add 1,4-cyclohexanedimethanol diglycidyl ether, ACMOSAL 82-869 and BYK-W 9010 to the mixture obtained in S3 and mix well; S5. Add the dicyandiamide fine powder to the mixture obtained in S4 and disperse it with a high-speed disperser until there is no agglomeration; S6. Add isophorone diamine to the mixture obtained in S5 and mix evenly to obtain the resin matrix; S7. Coat the resin matrix on the carrier film, compound it with the chopped fibers to make a sheet, and obtain the SMC composite material after thickening. Example 2

[0023] A flame-retardant SMC composite material capable of rapid prototyping, calculated by weight parts of raw materials, comprising 30-50 parts of chopped fibers and 50-70 parts of resin matrix; The resin matrix, by weight parts of raw materials, comprises: 35 parts of liquid bisphenol F epoxy resin, 13 parts of resorcinol diglycidyl ether, 30 parts of liquid phenolic epoxy resin, 10 parts of liquid multi-functional epoxy resin, 7 parts of dicyandiamide fine powder, 3 parts of BYK-P 9912, 0.6 parts of BYK-W 9010, 5 parts of flame retardant curing agent, 8 parts of ammonium octamolybdate, 18 parts of ammonium polyphosphate, 5 parts of melamine cyanurate, and 10 parts of 1,3-cyclohexanedimethanamine; Under this embodiment, a preparation method of a flame retardant SMC composite material capable of rapid prototyping comprises the steps of: S1. Weighing: Weigh 35 parts of liquid bisphenol F epoxy resin, 30 parts of liquid phenolic epoxy resin, 10 parts of liquid multi-functional epoxy resin, 13 parts of resorcinol diglycidyl ether, 7 parts of dicyandiamide fine powder, 3 parts of BYK-P 9912, 0.6 parts of BYK-W 9010, 5 parts of flame retardant curing agent, 8 parts of ammonium octamolybdate, 18 parts of ammonium polyphosphate, 5 parts of melamine cyanurate, and 10 parts of 1,3-cyclohexanedimethanamine according to the raw material ratio of the resin matrix; S2. Using a high-speed disperser to disperse 35 parts of liquid bisphenol F epoxy resin, 30 parts of liquid phenolic epoxy resin, 10 parts of liquid multi-functional epoxy resin, 18 parts of ammonium polyphosphate, 5 parts of melamine cyanurate, and 8 parts of ammonium octamolybdate until there is no agglomeration; S3. Adding the flame retardant curing agent to the mixture obtained in S2 and mixing thoroughly; S4. Adding resorcinol diglycidyl ether, BYK-P 9912, and BYK-W 9010 to the mixture obtained in S3 and mixing thoroughly; S5. Adding dicyandiamide fine powder to the mixture obtained in S4 and mixing and dispersing until there is no agglomeration; S6. Adding 1,3-cyclohexanedimethanamine to the mixture obtained in S5, mixing evenly to obtain the resin matrix; S7. Coating the resin matrix on a carrier film, compounding with chopped fibers to make a sheet, and thickening to obtain the SMC composite material. Example 3

[0024] A flame retardant SMC composite material capable of rapid prototyping, by weight parts of raw materials, comprises 30 - 50 parts of chopped fibers and 50 - 70 parts of resin matrix; The resin matrix, by weight parts of raw materials, comprises: 40 parts of liquid bisphenol A epoxy resin, 10 parts of 1,4-cyclohexanedimethanol diglycidyl ether, 30 parts of liquid phenolic epoxy resin, 7 parts of liquid multi-functional epoxy resin, 7 parts of bis(4-aminophenyl)sulfone, 2 parts of ACMOSAL 82-869, 0.6 parts of UNIQSPERSE P-193, 3 parts of flame retardant curing agent, 10 parts of ammonium octamolybdate, 15 parts of aluminum diethylphosphinate, 5 parts of melamine cyanurate, and 10 parts of isophorone diamine; Under this embodiment, a preparation method of a flame-retardant SMC composite material that can be rapidly prototyped includes the steps: S1. Weighing: Weigh 40 parts of liquid bisphenol A epoxy resin, 30 parts of liquid phenolic epoxy resin, 7 parts of liquid multi-functional epoxy resin, 10 parts of 1,4-cyclohexanedimethanol diglycidyl ether, 7 parts of bis(4-aminophenyl)sulfone, 2 parts of ACMOSAL 82-869, 0.6 part of UNIQSPERSE P-193, 3 parts of flame-retardant curing agent, 10 parts of ammonium octamolybdate, 15 parts of aluminum diethyl phosphinate, 5 parts of melamine cyanurate, and 10 parts of isophorone diamine according to the resin matrix raw material ratio; S2. Disperse the liquid bisphenol A epoxy resin, liquid phenolic epoxy resin, liquid multi-functional epoxy resin, aluminum diethyl phosphinate, melamine cyanurate, and ammonium octamolybdate using a high-speed disperser until there is no agglomeration; S3. Add the flame-retardant curing agent to the mixture obtained in S2 and mix well; S4. Add 1,4-cyclohexanedimethanol diglycidyl ether, ACMOSAL 82-869, and UNIQSPERSE P-193 to the mixture obtained in S3 and mix well; S5. Add bis(4-aminophenyl)sulfone to the mixture obtained in S4 and disperse until there is no agglomeration; S6. Add the thickening agent isophorone diamine to the mixture obtained in S5 and mix evenly to obtain the resin matrix; S7. Coat the resin matrix on a carrier film, compound it with chopped fibers to make a sheet, and after thickening, the SMC composite material can be obtained.

[0025] Comparative Example 1 The main difference between this comparative example and Example 1 is that there is no flame-retardant curing agent. In order to achieve flame-retardant performance, the amount of powder flame retardant is increased. And in order to prevent the viscosity increase caused by adding the flame retardant powder, the addition amount of the diluent is also increased.

[0026] An SMC composite material, by weight of raw materials, (30 - 50) parts of chopped fibers and (50 - 70) parts of resin matrix; The resin matrix, by weight of raw materials, includes: 40 parts of liquid bisphenol A epoxy resin, 20 parts of liquid phenolic epoxy resin, 13 parts of liquid multi-functional epoxy resin, 10 parts of resorcinol diglycidyl ether, 8 parts of dicyandiamide fine powder, 2 parts of ACMOSAL 82-869, 0.5 part of BYK-W 9010, 10 parts of zinc borate, 20 parts of aluminum diethyl phosphinate, 5 parts of melamine cyanurate, and 10 parts of isophorone diamine. Prepare the weighed raw materials according to the SMC material preparation (without flame-retardant curing agent) and the forming method to make a part.

[0027] The preparation method of the SMC composite material in this comparative example comprises: S1. Weighing: According to the ratio of the resin matrix raw materials, weigh 40 parts of liquid bisphenol A epoxy resin, 20 parts of liquid phenolic epoxy resin, 13 parts of liquid multifunctional epoxy resin, 10 parts of 1,4-cyclohexanedimethanol diglycidyl ether, 7 parts of dicyandiamide fine powder, 2 parts of ACMOSAL 82-869, 0.5 parts of BYK-W 9010, 10 parts of zinc borate, 20 parts of diethyl aluminum hypophosphite, 10 parts of melamine cyanurate, and 10 parts of isophorone diamine. S2. Fully mix liquid bisphenol A epoxy resin, liquid novolac epoxy resin, liquid multifunctional epoxy resin, 1,4-cyclohexanedimethanol diglycidyl ether, ACMOSAL 82-869, and BYK-W 9010 in a disperser.

[0028] S3. Add smoke suppressant zinc borate, flame retardant diethyl aluminum hypophosphite, melamine cyanurate, and curing agent dicyandiamide fine powder to the mixture obtained in S2, and disperse in a disperser until there is no agglomeration.

[0029] S4. Add isophorone diamine as a thickener to the mixture obtained in S3, and mix well to obtain a resin matrix.

[0030] S5. The resin matrix is ​​coated on a carrier film, and is compounded with short-cut fibers to form a sheet, and after thickening, an SMC composite material can be obtained.

[0031] Comparative Example 2 The difference between this comparative example and Example 2 is that: there is no flame retardant curing agent, and the flame retardant is used to replace the flame retardant curing agent. The amount of curing agent dicyandiamide fine powder is increased to replace the flame retardant curing agent to cure the resin.

[0032] An SMC composite material, comprising 30-50 parts of chopped fibers and 50-70 parts of a resin matrix, based on the weight of the raw materials; The resin matrix includes, by weight of raw materials, 35 parts of liquid bisphenol F epoxy resin, 12 parts of resorcinol diglycidyl ether, 30 parts of liquid novolac epoxy resin, 10 parts of liquid multifunctional epoxy resin, 9 parts of dicyandiamide fine powder, 3 parts of BYK-P9912, 0.6 parts of BYK-W 9010, 12 parts of ammonium octamolybdate, 15 parts of diethyl aluminum hypophosphite, 10 parts of ammonium polyphosphate, and 9 parts of 1,3-cyclohexanedimethylamine. The weighed raw materials are prepared according to the SMC material preparation (without flame retardant curing agent) and molding method to prepare a part.

[0033] The preparation method of the SMC composite material comprises: S1. Weighing: According to the resin matrix raw material ratio, weigh 35 parts of liquid bisphenol A epoxy resin, 30 parts of liquid novolac epoxy resin, 13 parts of liquid multifunctional epoxy resin, 12 parts of resorcinol diglycidyl ether, 9 parts of dicyandiamide fine powder, 3 parts of BYK-P9912, 0.6 parts of BYK-W 9010, 8 parts of ammonium octamolybdate, 15 parts of diethyl aluminum hypophosphite, 13 parts of ammonium polyphosphate, and 9 parts of 1,3-cyclohexanedimethylamine. S2. Fully mix liquid bisphenol A epoxy resin, liquid novolac epoxy resin, liquid multifunctional epoxy resin, resorcinol diglycidyl ether, BYK-P 9912 and BYK-W 9010 in a disperser.

[0034] S3. Add smoke suppressant zinc borate ammonium octamolybdate, flame retardant diethyl aluminum hypophosphite, ammonium polyphosphate, and curing agent dicyandiamide fine powder to the mixture obtained in S2, and disperse in a disperser until there is no agglomeration.

[0035] S4. Add thickener 1,3-cyclohexanedimethylamine to the mixture obtained in S3, and mix well to obtain a resin matrix.

[0036] S5. The resin matrix is ​​coated on a carrier film, and is compounded with short-cut fibers to form a sheet, and after thickening, an SMC composite material can be obtained.

[0037] Comparative Example 3 The difference between this comparative example and Example 3 is that there is no flame retardant curing agent, and the flame retardant is used to replace the flame retardant curing agent to achieve the same flame retardant effect. In order to help the resin mix with the flame retardant and the smoke suppressant, the amount of the wetting agent is increased.

[0038] An SMC composite material, comprising 30-50 parts of chopped fibers and 50-70 parts of a resin matrix, based on the weight of the raw materials; The resin matrix comprises, by weight of raw materials, 40 parts of liquid bisphenol A epoxy resin, 7 parts of 1,4-cyclohexanedimethanol diglycidyl ether, 30 parts of liquid phenolic epoxy resin, 7 parts of liquid multifunctional epoxy resin, 7 parts of bis(4-aminophenyl)sulfone, 2 parts of ACMOSAL 82-869, 1 part of UNIQSPERSE P-193, 10 parts of ammonium octamolybdate, 25 parts of diethylaluminum hypophosphite, 10 parts of melamine cyanurate, and 10 parts of isophorone diamine.

[0039] The preparation method of the SMC composite material comprises: S1. Weighing: Weigh 40 parts of liquid bisphenol A epoxy resin, 30 parts of liquid phenolic epoxy resin, 7 parts of liquid multi-functional epoxy resin, 10 parts of 1,4-cyclohexanedimethanol diglycidyl ether, 7 parts of bis(4-aminophenyl)sulfone, 2 parts of ACMOSAL 82-869, 1 part of UNIQSPERSE P-193, 10 parts of ammonium octamolybdate, 25 parts of aluminum diethylphosphinate, 10 parts of melamine cyanurate, and 10 parts of isophorone diamine according to the resin matrix raw material ratio. S2. Mix the liquid bisphenol A epoxy resin, liquid phenolic epoxy resin, liquid multi-functional epoxy resin, 1,4-cyclohexanedimethanol diglycidyl ether, ACMOSAL 82-869, and UNIQSPERSE P-193 thoroughly in a disperser.

[0040] S3. Add the smoke suppressant zinc borate octamolybdate, the flame retardant aluminum diethylphosphinate, melamine cyanurate, and the curing agent bis(4-aminophenyl)sulfone to the mixture obtained in S2, and disperse in a disperser until there is no agglomeration.

[0041] S4. Add the thickener isophorone diamine to the mixture obtained in S3, and mix evenly to obtain the resin matrix.

[0042] S5. Coat the resin matrix on a carrier film, and compound it with chopped fibers to make a sheet. After thickening, the SMC composite material can be obtained.

[0043] In this application, the viscosities and gel times of the resin matrices of Examples 1-3 and Comparative Examples 1-3 were tested (the gel time test execution standard: GB / T16995-1997), and the test results are shown in Table 1. Table 1. Test results of the viscosity and gel time of the resin mixture Project Example 1 Example 2 Example 3 Comparative Example Comparative Example 2 Comparative Example 3 Viscosity (@25°C) / mPa·s 1936 2103 2368 2861 3419 3762 Gel Time (@150°C) / s 112 131 128 167 163 169 As can be seen from Table 1: Since a powder flame retardant was used in the comparative example, the viscosity of the resin matrix increased, and this property would affect the wettability of the resin to the fibers, resulting in defects such as dry yarn in subsequent products; in addition, the gel time of the resin matrix in the examples was shorter, which was beneficial to shortening the molding cycle of subsequent parts.

[0044] In addition, the SMC composite materials of Examples 1-3 and Comparative Examples 1-3 were molded by compression molding. The appearance of the parts obtained in the examples was better than that of the comparative examples; in addition, the flame retardant properties and mechanical properties of the parts were tested, and the results are shown in detail in Table 2 and Table 3. Table 2. Test results of the flame retardant performance grade of the parts Project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 UL 94 V-0 V-0 V-0 V-1 V-1 V-1 Table 3. Test results of the mechanical properties of the parts Project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Tensile Strength / MPa 174 169 170 156 161 154 As can be seen from Table 2, Examples 1-3 can all reach the V-0 rating, and the overall flame retardant effect is better; as can be seen from Table 3, the tensile strength of the examples is superior to that of the comparative examples.

Claims

1. A flame-retardant SMC composite material capable of rapid prototyping, comprising, by weight, 30-50 parts of chopped fibers and 50-70 parts of a resin matrix, characterized in that: The resin matrix comprises, by weight of raw materials, 65-80 parts of liquid epoxy resin, 5-15 parts of diluent, 5-15 parts of curing agent, 0.5-3 parts of internal release agent, 6-15 parts of thickener, 0.3-1 parts of wetting agent, 2-5 parts of flame retardant curing agent, 5-30 parts of flame retardant (powder), and 5-15 parts of smoke suppressant (powder); the chopped fibers include carbon fiber, glass fiber, aramid fiber, etc.

2. The flame-retardant SMC composite material capable of rapid prototyping according to claim 1, characterized in that: The preparation method of the flame retardant curing agent comprises: Step 1: adding 100 parts of 9,10-dihydro-9-oxa-10-phosphaphenanthrene to 500 parts of anhydrous ethanol based on the weight of the raw materials, heating to 50-60° C., stirring and dissolving to obtain a 9,10-dihydro-9-oxa-10-phosphaphenanthrene solution; Step 2: Add 120 parts of hydrogen peroxide to the 9,10-dihydro-9-oxa-10-phosphaphenanthrene solution obtained in step 1, heat to 70-80° C., react for 5 hours, evaporate ethanol, and filter to obtain a white powder; Step 3, washing the white powder obtained in step 3 with acetone, and drying after washing to obtain DOPA; Step 4: Mix DOPA, 1-propylimidazole, phosphorous acid and anhydrous ethanol in a weight ratio of 5:10:2:60, heat to 60-70° C., stir and react for 1-2 hours, evaporate the ethanol to obtain a flame retardant curing agent.

3. The flame-retardant SMC composite material capable of rapid prototyping according to claim 1, characterized in that: The flame retardant should include one or more of diethyl aluminum hypophosphite, ammonium polyphosphate, piperazine pyrophosphate, and melamine cyanurate.

4. The flame-retardant SMC composite material capable of rapid prototyping according to claim 1, characterized in that: The smoke suppressant should include one or more of zinc borate, zinc stannate, and ammonium octamolybdate.

5. The flame-retardant SMC composite material capable of rapid prototyping according to claim 1, characterized in that: The epoxy resin may include one or more of liquid bisphenol A epoxy resin, liquid bisphenol F epoxy resin, liquid multifunctional epoxy resin, and liquid novolac epoxy resin.

6. The flame-retardant SMC composite material capable of rapid prototyping according to claim 1, characterized in that: The diluent should include one or more of 1,4-cyclohexanedimethanol diglycidyl ether and resorcinol diglycidyl ether.

7. The flame-retardant SMC composite material capable of rapid prototyping according to claim 1, characterized in that: The curing agent should include one or more of dicyandiamide fine powder, bis(4-aminophenyl)sulfone, and 4,4'-diaminodiphenylmethane.

8. The flame-retardant SMC composite material capable of rapid prototyping according to claim 1, characterized in that: The internal mold release agent may include one or more of ACMOSAL 82-869, BYK-P 9080, and BYK-P 9912.

9. The flame-retardant SMC composite material capable of rapid prototyping according to claim 1, characterized in that: The thickener may include one or more of 1,3-cyclohexanedimethylamine, 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane, and isophoronediamine; the wetting agent may include one or more of BYK-9076, BYK-W 9010, and UNIQSPERSE P-193.

10. A method for preparing a flame-retardant SMC composite material capable of rapid prototyping, based on the SMC composite material according to any one of claims 1 to 9, characterized in that: Includes steps: S1. Weighing: According to the ratio of the resin matrix raw materials, weigh 65-80 parts of liquid epoxy resin, 5-15 parts of diluent, 5-15 parts of curing agent, 0.5-3 parts of internal release agent, 10-15 parts of thickener, 0.3-1 parts of wetting agent, 2-5 parts of flame retardant curing agent, 5-30 parts of flame retardant, and 5-15 parts of smoke suppressant; S2. Dispersing the liquid epoxy resin, flame retardant and smoke suppressant to a non-agglomerated state using a high-speed disperser; S3, adding a flame retardant curing agent to the mixture obtained in S2, and mixing thoroughly; S4, adding a diluent, an internal release agent, and a wetting agent to the mixture obtained in S3, and mixing them thoroughly; S5, adding a curing agent to the mixture obtained in S4, mixing and dispersing until there is no agglomeration; S6, adding a thickener to the mixture obtained in S5, and mixing evenly to obtain a resin matrix; S7. The resin matrix is ​​coated on a carrier film, and is compounded with short-cut fibers to form a sheet, and after thickening, an SMC composite material can be obtained.