Tough benzoxazine resin laminated board and preparation method thereof

Abstract

The invention relates to a tough benzoxazine resin laminated board and a preparation method thereof, and belongs to the field of laminated boards. The tough benzoxazine resin composition is used as a matrix, a reinforcing material is used as a base material, prepreg sheets are prepared by impregnating the reinforcing material with the tough benzoxazine resin composition, the obtained prepreg sheets are stacked according to a designed matching mode, and the tough benzoxazine resin laminated board is obtained through hot press molding. According to the tough benzoxazine resin composition synthesized by the invention, the toughness is greatly improved on the basis of retaining excellent heat resistance and mechanical properties of benzoxazine resin. According to the tough benzoxazine resin laminated board disclosed by the invention, the impact strength and the return force can be improved by 20% or more through the verification of impact strength verification and return force test; the composite material also has the characteristics of high strength, high temperature resistance, high toughness and the like, can be processed into various plate-shaped springs according to requirements, and is suitable for application scenes of non-metal composite materials with high elasticity and high toughness requirements.

Description

Technical Field

[0001] The invention relates to the technical field of thermosetting resins and composite materials thereof, in particular to a tough benzoxazine resin laminate and a preparation method thereof. Background Art

[0002] Electromagnetic vibration equipment is widely used in mining, coal, metallurgy, electricity, chemical industry, machinery, food and other industries. Most of these equipment use fiber-reinforced resin-based composite materials as leaf springs. Compared with traditional metal materials, composite materials have significant advantages such as long fatigue life, high specific strength and specific modulus, higher energy storage capacity and certain damping, good vibration reduction performance, corrosion resistance, easy processing, and strong designability.

[0003] Benzoxazine is a class of nitrogen-containing heterocyclic compounds synthesized from amines, phenols and aldehyde compounds. Due to the large number of aromatic ring structures in benzoxazine resin, although the cured product has good heat resistance, it is brittle and has poor impact resistance, which is not conducive to the widespread application and promotion of benzoxazine resin fiber composite materials in non-metallic structural parts, especially in electromagnetic vibration equipment, because the heat generated during long-term operation can easily lead to a decrease in amplitude, and the lack of toughness can lead to a small feeding amplitude, which can easily cause defects such as low accuracy.

[0004] Based on this, the present invention is proposed. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a tough benzoxazine resin laminate and a preparation method thereof, and the technical scheme thereof is as follows:

[0006] A tough benzoxazine resin laminated board is provided, which takes a tough benzoxazine resin composition as a matrix and a reinforcing material as a base material. A prepreg is prepared by impregnating the reinforcing material with the tough benzoxazine resin composition, and the obtained prepreg is stacked and laid according to a designed matching method, and the tough benzoxazine resin laminated board is obtained by hot pressing.

[0007] The tough benzoxazine resin composition contains a tough benzoxazine resin, and the structural formula of the tough benzoxazine resin is as shown in Formula I.

[0008]

[0009] Among them, R, R 1 , R 2 , R 3 All are alkyl.

[0010] Preferably, the weight ratio of the reinforcing material to the tough benzoxazine resin laminate is 30% to 60%.

[0011] Preferably, the tough benzoxazine resin composition comprises the following raw materials in parts by weight:

[0012]

[0013] Preferably, the phenolic compound is one or more of phenol, bisphenol A, o-cresol, hydroquinone, resorcinol and the like.

[0014] Preferably, the solvent A is one or more of toluene, xylene, butanone, formamide, dimethylformamide, dimethylacetamide, etc.

[0015] Preferably, the modified amine compound is one or more of 1,2-ethylenediamine, 1,4-butanediamine, 1,6-hexanediamine, 1,8-octanediamine, 1,12-diaminododecane, urea (urea), organic urea (UR300, UR500), polyetheramine (polyetheramine 230, polyetheramine 400, polyetheramine 2000), etc.

[0016] Preferably, the solvent B is one or more of toluene, xylene, formamide, dimethylformamide, dimethylacetamide, butanone, acetone and the like.

[0017] Preferably, the accelerator is one or more of dimethylimidazole, diethyltetramethylimidazole, DMP-30, triethylamine, boron trifluoride monoethylamine and the like.

[0018] Preferably, the reinforcing material is one or more of glass fiber, polyester fiber, carbon fiber, aramid fiber, high silica glass fiber, quartz fiber, basalt fiber, glass fiber cloth (including but not limited to 7628 / 7629 electronic grade glass fiber cloth, EW-100 / EW-140 / EW-180 alkali-free glass fiber cloth, 300g / 400g / 600g untwisted roving woven cloth), polyester fiber cloth, carbon fiber cloth, aramid fiber cloth, high silica glass fiber cloth, quartz fiber cloth, basalt fiber cloth and other fibers or fabrics.

[0019] As a further improvement, the method for preparing the tough benzoxazine resin laminate comprises the following steps:

[0020] Step 1, putting melted phenol into a reactor, adding solvent A and mixing;

[0021] Step 2, adding diaminodiphenylmethane and modified amine compounds, mixing and stirring until the reactants are completely dissolved;

[0022] Step 3, after adding paraformaldehyde, heating up and keeping the temperature at 40-120° C. for 1-12 hours;

[0023] Step 4: After the heat preservation reaction is completed, vacuum distillation is performed, solvent B is added and stirred until the reactants are completely dissolved, the temperature is lowered to room temperature, and an accelerator is added to obtain the tough benzoxazine resin composition;

[0024] Step 5, immersing the reinforcing material into a glue tank containing a tough benzoxazine resin composition, and sending the reinforcing material into an oven after immersion, and obtaining a prepreg after drying; wherein the glue content of the prepreg is controlled to be 30-70wt%;

[0025] Step 6, stacking and laying the prepreg sheets according to the designed matching method, and then transferring the stacked semi-cured prepreg sheets to the hydraulic press mold for hot pressing. The hot pressing process is as follows: the mold is heated to 120-125°C, pressurized to 4.5-5MPa, and kept warm for 25-30min; then heated to 145-150°C, pressurized to 9.5-10MPa, and kept warm for 10-15min; heated to 160-165°C, pressurized to 14.5-15MPa, and kept warm for 10-15min; then heated to 180-210°C, maintained at temperature and pressure for 2-6 hours, and then cooled to below 60°C for demolding to obtain the tough benzoxazine resin laminate.

[0026] Preferably, the prepreg sheets are arranged as follows:

[0027] When the reinforcing fiber is glass fiber or glass fiber cloth, the corresponding prepreg is marked as prepreg A;

[0028] When the reinforcing fiber is polyester fiber, carbon fiber, aramid fiber, high silica glass fiber, quartz fiber, basalt fiber, polyester fiber cloth, carbon fiber cloth, aramid fiber cloth, high silica glass fiber cloth, quartz fiber cloth or basalt fiber cloth, the corresponding prepreg is marked as prepreg B, and the reinforcing fiber used in prepreg B is one or more;

[0029] Method 1: Prepreg sheet A is stacked in the middle, and prepreg sheet B is evenly divided into two parts and placed on both sides of prepreg sheet A respectively;

[0030] Method 2: Prepreg sheet B is stacked in the middle, and prepreg sheet A is evenly divided into two parts and placed on both sides of prepreg sheet B respectively;

[0031] Method 3: Prepreg sheets A are first stacked, and prepreg sheets B are evenly inserted into the stack of prepreg sheets A in an intercalation manner.

[0032] Preferably, the prepreg is prepared in one of the following ways: way 1, way 2, way 3, way 4 or way 5;

[0033] Method 1:

[0034] When the reinforcing fiber is glass fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet C;

[0035] When the reinforcing fiber is aramid fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet D;

[0036] The prepreg sheet D is stacked in the middle, and the prepreg sheet C is evenly divided into two parts and placed on both sides of the prepreg sheet D respectively;

[0037] Method 2:

[0038] When the reinforcing fiber is glass fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet C;

[0039] When the reinforcing fiber is aramid fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet D;

[0040] First, the prepreg sheets C are stacked, and the prepreg sheets D are inserted into the stack of prepreg sheets C in an intercalation manner;

[0041] Method 3:

[0042] When the reinforcing fiber is glass fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet C;

[0043] When the reinforcing fiber is aramid fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet D;

[0044] The prepreg sheet C is stacked in the middle, and the prepreg sheet D is evenly divided into two parts and placed on both sides of the prepreg sheet C respectively;

[0045] Method 4:

[0046] When the reinforcing fiber is glass fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet C;

[0047] When the reinforcing fiber is basalt fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet E;

[0048] The prepreg sheet C is stacked in the middle, and the prepreg sheet E is evenly divided into two parts and placed on both sides of the prepreg sheet C respectively;

[0049] Method 5:

[0050] When the reinforcing fiber is glass fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet C;

[0051] When the reinforcing fiber is aramid fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet D;

[0052] When the reinforcing fiber is basalt fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet E;

[0053] Prepreg C is stacked in the middle, prepreg E is evenly divided into two parts and placed on both sides of prepreg C to obtain an intermediate layer, and finally prepreg D is evenly divided into two parts and placed on both sides of the intermediate layer.

[0054] Beneficial effects of the present invention:

[0055] 1. The tough benzoxazine resin composition synthesized in the present invention greatly improves toughness while retaining the excellent heat resistance and mechanical properties of the benzoxazine resin.

[0056] 2. The tough benzoxazine resin laminate of the present invention can improve the impact strength and return force by 20% or more through impact strength verification and return force test.

[0057] 3. The tough benzoxazine resin laminate of the present invention has the characteristics of high strength, high temperature resistance, high toughness, etc., and can be processed into various types of leaf springs as required, and is suitable for application scenarios of non-metallic composite materials with high elasticity and high toughness requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 The prepreg intercalation stacking method in Example 5;

[0059] Figure 2 The prepreg interlayer stacking method in Example 6;

[0060] Figure 3 The prepreg intercalation stacking method in Example 7;

[0061] Figure 4 The prepreg intercalation stacking method in Example 8;

[0062] Figure 5 The prepreg intercalation stacking method in Example 9;

[0063] Figure 6 This is a schematic diagram of the return force sample;

[0064] Figure 7 Schematic diagram of the return force sample assembled on the test fixture. DETAILED DESCRIPTION

[0065] The present invention is described in detail below in conjunction with specific embodiments. The embodiments described below are only 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 skilled in the art without creative work are within the scope of protection of the present invention.

[0066] Embodiment 1:

[0067] Prepare a three-necked flask, weigh 400g of molten phenol, add 400g of toluene, stir and mix evenly, add 380g of diaminodiphenylmethane, stir until completely dissolved and mixed evenly;

[0068] Add 50g of polyetheramine D230, mix well, add 260g of paraformaldehyde, heat to 90℃ and keep warm for 240min;

[0069] The vacuum distillation was carried out, and the vacuum was released after completion. The temperature was lowered and dimethylformamide was added to adjust the solid content to 61% to obtain a resin liquid. 0.6 g of dimethylimidazole was weighed, dissolved, and added to the resin liquid for mixing, and the gel time was adjusted to 200 to 260 s. A modified benzoxazine resin composition was obtained.

[0070] The modified benzoxazine resin composition was used to impregnate 7628 electronic grade glass cloth to obtain a prepreg with a glue content of 38%. The prepregs were stacked and placed in a mold and hot-pressed at 180°C and 15MPa for 5 hours. The mold was cooled to below 60°C and demolded to obtain a 5mm thick blank. The obtained sample was marked as 1#. Test strips were cut and a 100mm*200mm test plate was cut for return force test. The performance test results are shown in Table 1.

[0071] Embodiment 2:

[0072] Prepare a three-necked flask, weigh 400g of molten phenol, add 400g of toluene, stir and mix evenly, add 336g of diaminodiphenylmethane, stir until completely dissolved and mixed evenly;

[0073] Add 96g of polyetheramine D230, mix well, add 260g of paraformaldehyde, heat to 90℃ and keep warm for 240min;

[0074] The vacuum distillation was carried out, and the vacuum was released after completion. The temperature was lowered and dimethylformamide was added to adjust the solid content to 60.2% to obtain a resin liquid. 0.8 g of dimethylimidazole was weighed, dissolved, and added to the resin liquid for mixing, and the gel time was adjusted to 200-260 s. A modified benzoxazine resin composition was obtained.

[0075] The modified benzoxazine resin composition was used to impregnate 7628 electronic grade glass cloth to obtain a prepreg with a glue content of 38%. The prepregs were stacked and placed in a mold and hot-pressed at 180°C and 15MPa for 5 hours. The mold was cooled to below 60°C and demolded to obtain a 5mm thick blank. The obtained sample was marked as 2#. Test strips were cut and a 100mm*200mm test plate was cut for return force test. The performance test results are shown in Table 1.

[0076] Embodiment 3:

[0077] Prepare a three-necked flask, weigh 400g of molten phenol, add 400g of toluene, stir and mix evenly, add 295g of diaminodiphenylmethane, stir until completely dissolved and mixed evenly;

[0078] Add 147g of polyetheramine D230, mix well, add 260g of paraformaldehyde, heat to 90℃ and keep warm for 240min;

[0079] The vacuum distillation was carried out, and the vacuum was released after completion. The temperature was lowered and dimethylformamide was added to adjust the solid content to 60.2% to obtain a resin liquid. 0.8 g of dimethylimidazole was weighed, dissolved, and added to the resin liquid for mixing, and the gel time was adjusted to 200-260 s. A modified benzoxazine resin composition was obtained.

[0080] The modified benzoxazine resin composition was used to impregnate 7628 electronic grade glass cloth to obtain a prepreg with a glue content of 38%. The prepregs were stacked and placed in a mold and hot-pressed at 180°C and 15MPa for 5 hours. The mold was cooled to below 60°C and demolded to obtain a 5mm thick blank. The obtained sample was marked as 3#. Test strips were cut and a 100mm*200mm test plate was cut for return force test. The performance test results are shown in Table 1.

[0081] Embodiment 4:

[0082] Prepare a three-necked flask, weigh 400g of molten phenol, add 400g of toluene, stir and mix evenly, add 253g of diaminodiphenylmethane, stir until completely dissolved and mixed evenly;

[0083] Add 196g of polyetheramine D230, mix well, add 260g of paraformaldehyde, heat to 90℃ and keep warm for 240min;

[0084] The vacuum distillation was carried out, and the vacuum was released after completion. The temperature was lowered and dimethylformamide was added to adjust the solid content to 60.2% to obtain a resin liquid. 0.8 g of dimethylimidazole was weighed, dissolved, and added to the resin liquid for mixing, and the gel time was adjusted to 200-260 s. A modified benzoxazine resin composition was obtained.

[0085] The modified benzoxazine resin composition was used to impregnate 7628 electronic grade glass cloth to obtain a prepreg with a glue content of 38%. The prepregs were stacked and placed in a mold and hot-pressed at 180°C and 15MPa for 5 hours. The mold was cooled to below 60°C and demolded to obtain a 5mm thick blank. The obtained sample was marked as 4#. Test strips were cut and a 100mm*200mm test board was cut for return force test. The performance test results are shown in Table 1.

[0086] Embodiment 5:

[0087] The modified benzoxazine resin composition described in Example 2 was used to impregnate 7628 electronic grade glass cloth to obtain a prepreg having a glue content of 38%, which was marked as 5-1.

[0088] The modified benzoxazine resin composition described in Example 2 was used to impregnate the aramid fiber cloth to obtain a prepreg sheet having a glue content of 36%, which was marked as 5-2.

[0089] Press the above 5-1 prepreg and 5-2 prepreg into Figure 1 The layers were stacked and placed in a mold and hot-pressed at 180°C and 15MPa for 5 hours, then cooled to below 60°C and demolded to obtain a 5mm thick blank. The obtained sample was marked as 5#. Test strips were cut and a 100mm*200mm test plate was cut for return force test. The performance test results are shown in Table 1.

[0090] Embodiment 6:

[0091] The 5-1 prepreg and the 5-2 prepreg in Example 5 were pressed Figure 2 The layers were stacked and placed in a mold and hot-pressed at 180°C and 15MPa for 5 hours, then cooled to below 60°C and demolded to obtain a 5mm thick blank. The obtained sample was marked as 6#. Test strips were cut and a 100mm*200mm test plate was cut for return force test. The performance test results are shown in Table 2.

[0092] Embodiment 7:

[0093] The 5-1 prepreg and the 5-2 prepreg in Example 5 were pressed Figure 3 The layers were stacked and placed in a mold and hot-pressed at 180°C and 15MPa for 5 hours, then cooled to below 60°C and demolded to obtain a 5mm thick blank. The obtained sample was marked as 7#. Test strips were cut and a 100mm*200mm test plate was cut for return force test. The performance test results are shown in Table 2.

[0094] Embodiment 8:

[0095] The modified benzoxazine resin composition described in Example 2 was used to impregnate basalt fiber cloth to obtain a prepreg sheet with a glue content of 36%, which was marked as 8-2.

[0096] The 5-1 prepreg in Example 5 and the 8-2 prepreg in Example 8 were mixed in a Figure 4 The layers were stacked and placed in a mold and hot-pressed at 180°C and 15MPa for 5 hours, then cooled to below 60°C and demolded to obtain a 5mm thick blank. The obtained sample was marked as 8#. Test strips were cut and a 100mm*200mm test plate was cut for return force test. The performance test results are shown in Table 2.

[0097] Embodiment 9:

[0098] The 5-1 prepreg and the 5-2 prepreg in Example 5 and the 8-2 prepreg in Example 8 were mixed in a Figure 5The layers were stacked and placed in a mold and hot-pressed at 180°C and 15 MPa for 5 hours, then cooled to below 60°C and demolded to obtain a 5 mm thick blank. The obtained sample was marked as 9#, and test strips were cut and a 100 mm*200 mm test plate was cut for return force test.

[0099] Comparative Example 1:

[0100] Commercially available benzoxazine resin is dissolved in dimethylformamide to form a resin solution with a solid content of 58-62%.

[0101] The above resin solution was used to impregnate 7628 electronic grade glass cloth to obtain a prepreg with a glue content of 38%. After the above prepregs were stacked, they were placed in a mold and hot-pressed at 180°C and 15MPa for 7 hours, then cooled to below 60°C for demolding to obtain a 5mm thick blank. The obtained sample was marked as D1#. Test strips were cut and a 100mm*200mm test plate was cut for return force test. The performance test results are shown in Table 2.

[0102] Return force test:

[0103] The test plates prepared in Examples 1 to 9 and Comparative Example 1 were processed into Figure 6 As shown in the return force sample, the return force sample (i.e., spring leaf) is assembled on the test fixture, as shown in the Figure 7 As shown, the spring sheet is vertically fixed on the fixing clamp with bolts, and a hammer is fixed on the upper part. The hammer is aligned with the center of the slider, and after the slider contacts the surface of the hammer, the spring sheet is pulled backward, deviated from the original position by a certain amplitude (such as 3cm) and then locked; during the test, the lock is released, the spring sheet is released, the spring sheet rebounds, and the slider is hit by the hammer. The slider is subjected to force and then slides out on the slide with a scale and stops. The sliding distance is recorded as F, which is recorded as the return force.

[0104] Table 1: Comparison of toughening effects of different solutions

[0105]

[0106]

[0107] Table 2: Comparison of toughening effects of different solutions

[0108]

[0109] As can be seen from Tables 1 and 2, Example 9 has the best comprehensive performance, and has excellent impact strength, heat resistance and impact return force performance. After the tough benzoxazine resin laminate is used as a leaf spring, the rebound effect of the equipment is improved.

[0110] The tough benzoxazine resin laminate of the present invention is prepared by compounding a variety of fiber prepregs according to a designed stacking process. The preparation method is simple, the performance is excellent, and the designability is high. The laminate can be used as a plate spring component for electromagnetic vibration equipment used in mining, coal, metallurgy, electric power, chemical industry, machinery, food and other industries.

[0111] In addition, it should be understood that those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A tough benzoxazine resin laminate, characterized in that: The tough benzoxazine resin composition is used as a matrix and a reinforcing material is used as a base material. A prepreg is prepared by impregnating the reinforcing material with the tough benzoxazine resin composition. The obtained prepreg is stacked and laid according to a designed matching method, and the tough benzoxazine resin laminate is obtained by hot pressing.

2. A tough benzoxazine resin laminate according to claim 1, characterized in that: The tough benzoxazine resin composition comprises the following raw materials in parts by weight:

3. A tough benzoxazine resin laminate according to claim 1, characterized in that: The mass ratio of the reinforcing material to the tough benzoxazine resin laminate is 30% to 60%.

4. A tough benzoxazine resin laminate according to claim 2, characterized in that: The phenolic compound is one or more of phenol, bisphenol A, o-cresol, hydroquinone, and resorcinol; and / or, The solvent A is one or more of toluene, xylene, butanone, formamide, dimethylformamide, and dimethylacetamide; and / or, The modified amine compound is one or more of 1,2-ethylenediamine, 1,4-butylenediamine, 1,6-hexanediamine, 1,8-octanediamine, 1,12-diaminododecane, urea, organic urea, and polyetheramine; and / or, The solvent B is one or more of toluene, xylene, formamide, dimethylformamide, dimethylacetamide, butanone, and acetone; and / or, The accelerator is one or more of dimethylimidazole, diethyltetramethylimidazole, 2,4,6-tris(dimethylaminomethyl)phenol, triethylamine, and boron trifluoride monoethylamine.

5. A tough benzoxazine resin laminate according to claim 2, characterized in that: The reinforcing material is one or more of glass fiber, polyester fiber, carbon fiber, aramid fiber, high silica glass fiber, quartz fiber, basalt fiber, glass fiber cloth, polyester fiber cloth, carbon fiber cloth, aramid fiber cloth, high silica glass fiber cloth, quartz fiber cloth, and basalt fiber cloth.

6. A method for preparing a tough benzoxazine resin laminate according to any one of claims 1 to 5, characterized in that: The following steps are involved: As a further improvement, the method for preparing the tough benzoxazine resin laminate comprises the following steps: Step 1, putting melted phenol into a reactor, adding solvent A and mixing; Step 2, adding diaminodiphenylmethane and modified amine compounds, mixing and stirring until the reactants are completely dissolved; Step 3, after adding paraformaldehyde, heating up and keeping the temperature at 40-120° C. for 1-12 hours; Step 4: After the heat preservation reaction is completed, vacuum distillation is performed, solvent B is added and stirred until the reactants are completely dissolved, the temperature is lowered to room temperature, and an accelerator is added to obtain a tough benzoxazine resin composition; Step 5, immersing the reinforcing material into a glue tank containing a tough benzoxazine resin composition, and sending the reinforcing material into an oven after impregnation, and obtaining a prepreg after drying; Step 6: stack and lay the prepreg sheets according to the designed matching method, and then transfer the stacked semi-cured prepreg sheets to a hydraulic press mold for hot pressing to obtain the tough benzoxazine resin laminate.

7. The method for preparing a tough benzoxazine resin laminate according to claim 6, characterized in that: In step 6, the prepreg sheets are assembled as follows: When the reinforcing fiber is glass fiber or glass fiber cloth, the corresponding prepreg is marked as prepreg A; When the reinforcing fiber is polyester fiber, carbon fiber, aramid fiber, high silica glass fiber, quartz fiber, basalt fiber, polyester fiber cloth, carbon fiber cloth, aramid fiber cloth, high silica glass fiber cloth, quartz fiber cloth or basalt fiber cloth, the corresponding prepreg is marked as prepreg B, and the reinforcing fiber used in prepreg B is one or more; Method 1: Prepreg sheet A is stacked in the middle, and prepreg sheet B is evenly divided into two parts and placed on both sides of prepreg sheet A respectively; Method 2: Prepreg sheet B is stacked in the middle, and prepreg sheet A is evenly divided into two parts and placed on both sides of prepreg sheet B respectively; Method 3: Prepreg sheets A are first stacked, and prepreg sheets B are evenly inserted into the stack of prepreg sheets A in an intercalation manner.

8. The method for preparing a tough benzoxazine resin laminate according to claim 6, characterized in that: In step 6, the prepreg is prepared in one of the following ways: way 1, way 2, way 3, way 4 or way 5; Method 1: When the reinforcing fiber is glass fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet C; When the reinforcing fiber is aramid fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet D; The prepreg sheet D is stacked in the middle, and the prepreg sheet C is evenly divided into two parts and placed on both sides of the prepreg sheet D respectively; Method 2: When the reinforcing fiber is glass fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet C; When the reinforcing fiber is aramid fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet D; First, the prepreg sheets C are stacked, and the prepreg sheets D are inserted into the stack of prepreg sheets C in an intercalation manner; Method 3: When the reinforcing fiber is glass fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet C; When the reinforcing fiber is aramid fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet D; The prepreg sheet C is stacked in the middle, and the prepreg sheet D is evenly divided into two parts and placed on both sides of the prepreg sheet C respectively; Method 4: When the reinforcing fiber is glass fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet C; When the reinforcing fiber is basalt fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet E; The prepreg sheet C is stacked in the middle, and the prepreg sheet E is evenly divided into two parts and placed on both sides of the prepreg sheet C respectively; Method 5: When the reinforcing fiber is glass fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet C; When the reinforcing fiber is aramid fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet D; When the reinforcing fiber is basalt fiber cloth, the corresponding prepreg sheet is marked as prepreg sheet E; Prepreg C is stacked in the middle, prepreg E is evenly divided into two parts and placed on both sides of prepreg C to obtain an intermediate layer, and finally prepreg D is evenly divided into two parts and placed on both sides of the intermediate layer.

9. The method for preparing a tough benzoxazine resin laminate according to claim 6, characterized in that: In step 6, the hot pressing process is as follows: the mold is heated to 120-125°C, pressurized to 4.5-5MPa, and kept warm for 25-30 minutes; then heated to 145-150°C, pressurized to 9.5-10MPa, and kept warm for 10-15 minutes; heated to 160-165°C, pressurized to 14.5-15MPa, and kept warm for 10-15 minutes; then heated to 180-210°C, maintained at temperature and pressure for 2-6 hours, and then cooled to below 60°C for demolding.

10. The method for preparing a tough benzoxazine resin laminate according to claim 6, characterized in that: In step 5, the glue content of the prepreg is controlled to be 30-70 wt %.

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