Polydopamine modified basalt fiber reinforced MC nylon composite material and preparation method thereof

Abstract

The invention discloses a polydopamine modified basalt fiber reinforced MC nylon composite material and a preparation method thereof, and belongs to the field of nylon composite materials. The polydopamine modified basalt fiber reinforced MC nylon composite material comprises a polydopamine modified basalt fiber and an MC nylon matrix. The preparation method comprises the following steps: desizing basalt fibers, modifying the basalt fibers in manners of polydopamine coating and the like, and then carrying out in-situ polymerization on caprolactam monomers on the modified basalt fibers to prepare the polydopamine modified basalt fiber / MC nylon composite material. A modifier of the basalt fiber comprises polydopamine synthesized by a dopamine hydrochloride-Tris solution. The basalt fiber / nylon composite material with excellent mechanical strength is prepared by modifying the surface of the basalt fiber aiming at the characteristic of weak affinity of the existing basalt fiber and nylon material, and has the advantages of environmental friendliness and excellent mechanical property.

Description

Technical Field

[0001] The present invention belongs to the field of nylon composites, and particularly relates to a polydopamine-modified basalt fiber reinforced MC nylon composite material and a preparation method thereof. Background Art

[0002] Compared with thermosetting composites, thermoplastic composites have the advantages of convenient processing, high toughness, less harmful chemical components, degradability, and being conducive to recycling. In the general environment of severe plastic pollution since the 20th century, it conforms to the concept of green environmental protection in contemporary society. Basalt fiber has a higher elongation rate than carbon fiber and its cost is more than 50% lower. Compared with glass fiber, it has higher modulus, heat resistance, alkali resistance, non-toxicity, and green environmental protection. Compared with organic fiber, it has high strength, high elongation rate, high temperature resistance, corrosion resistance, lower cost, and green environmental protection. The combination of basalt fiber and thermoplastic resin has good practicability on the basis of green environmental protection and has a broad development prospect.

[0003] Due to the high melt viscosity of thermoplastic resins, the impregnation of fibers is poor, and usually high temperature and high pressure conditions are required to achieve, which greatly limits the development and application of carbon fiber reinforced thermoplastic resin composites. Caprolactam has a low melt viscosity, rapid anionic polymerization, and no by-products are generated during the polymerization process. By using in-situ polymerization of caprolactam, the problems of high viscosity of nylon 6 in the molten state and difficult impregnation of fibers can be effectively avoided. However, the surface of basalt fiber is inert, and the interfacial interaction force between it and MC nylon is weak, resulting in the performance of basalt fiber / MC nylon composites not meeting the expectations, and the surface of basalt fiber needs to be modified. Summary of the Invention

[0004] The purpose of the present application is to provide a polydopamine-modified basalt fiber reinforced MC nylon composite material and a preparation method thereof to solve the problem of poor affinity between basalt fiber and MC nylon matrix. In the present invention, after the basalt fiber is desized, the surface of the desized basalt fiber is modified to form a polydopamine coating on the surface of the basalt fiber, and then it is added to the production process of MC nylon to prepare a polydopamine-modified basalt fiber reinforced MC nylon composite material. After the polydopamine coating is added to the surface of the basalt fiber, the affinity between the basalt fiber and the MC nylon matrix and the surface roughness of the fiber can be improved, thereby improving the mechanical properties of the composite material.

[0005] To achieve the above purpose, the preparation scheme adopted by the present invention is as follows:

[0006] A polydopamine-modified basalt fiber reinforced MC nylon composite material, the composite material comprises the following components:

[0007] 15 - 30 parts by mass of modified basalt fiber;

[0008] 70 - 85 parts by mass of MC nylon matrix;

[0009] Among them, the modified basalt fiber includes desized basalt fiber and a modifier, and the weight ratio of the desized basalt fiber to the modifier is 100:1 - 5; the modifier includes but is not limited to at least one of polydopamine, KH550, KH560, and PEG.

[0010] Preferably, the viscosity-average molecular weight of the MC nylon matrix is 45,000 - 75,000, and the monomer conversion rate is 95 - 99%.

[0011] Preferably, the catalysts used for preparing the MC nylon matrix include but are not limited to sodium caprolactamate, NaH, or NaOH, and the cocatalysts include but are not limited to TDI or MDI.

[0012] Preferably, when preparing the MC nylon matrix, the catalyst dosage is 0.1 - 0.3 wt%, and the cocatalyst dosage is 0.5 wt% - 0.7 wt%.

[0013] Preferably, the polymerization temperature of the MC nylon matrix is 150 - 190 °C, and the polymerization time is 45 - 120 min.

[0014] Preferably, the modified basalt fiber is modified desized basalt fiber; and the content of the surface modifier of the basalt fiber is 1 - 5 wt%, and the modifier is polydopamine.

[0015] Preferably, the desizing methods of the desized basalt fiber include thermal desizing and acetone desizing. The thermal desizing conditions are 300 - 450 °C and 0.5 - 4 h, and the acetone desizing conditions are reflux at 70 - 90 °C for 1 - 12 h.

[0016] Preferably, the modified basalt fiber is prepared according to the following method:

[0017] (1) Subject the basalt fiber to thermal desizing or acetone desizing, wash it with deionized water, and then dry it;

[0018] (2) Put the desized basalt fiber obtained in step (1) into a hydrochloric acid dopamine - Tris solution and stir;

[0019] (3) Dry the modified basalt fiber obtained in step (2) to obtain the modified basalt fiber.

[0020] Preferably, in step (2), the stirring time is 12 - 48 h, the concentration of hydrochloric acid dopamine is 1 - 5 g / L, and the Tris concentration is 0.008 - 0.012 mol / L.

[0021] The preparation method of the polydopamine-modified basalt fiber reinforced MC nylon composite material described in any one of the above, comprises the following steps:

[0022] S1 Desizing of basalt fiber;

[0023] S2 Preparation of modified basalt fiber;

[0024] S3 Preparation of polydopamine-modified basalt fiber reinforced MC nylon composite material;

[0025] S4 Post-treatment.

[0026] Specifically,

[0027] (1) Desize the basalt fiber, then add dopamine hydrochloride for modification to obtain modified basalt fiber;

[0028] (2) Preheat the mold to the polymerization temperature of 150 - 190 °C, and add the obtained modified basalt fiber;

[0029] (3) Heat the caprolactam monomer to 140 - 155 °C, control the vacuum degree at 0.09 - 0.10 MPa using a vacuum pump, and pump for 15 - 30 min;

[0030] (4) Add a catalyst with a dosage of 0.1 - 0.3 wt% to the caprolactam obtained in step (3), and again control the vacuum degree at 0.09 - 0.10 MPa using a vacuum pump, and pump for 15 - 30 min;

[0031] (5) Add a co-catalyst with a dosage of 0.5 - 0.7 wt% to the caprolactam obtained in step (4), stir evenly and then pour it into the mold containing the modified basalt fiber; the dosage of the modified basalt fiber is 15 - 30 wt%;

[0032] (6) After polymerization for 45 - 120 min, cool, and perform post-treatment in a water bath or oil bath at 70 - 90 °C for 1 - 5 h.

[0033] Compared with the prior art, the present invention has the following advantages and technical effects:

[0034] (1) The present invention uses modifiers such as polydopamine to modify the surface of the desized basalt fiber, effectively improving the affinity between the basalt fiber and the MC nylon matrix and the surface roughness of the fiber, and making an environmentally friendly and excellent mechanical property fiber-reinforced thermoplastic composite material.

[0035] (2) For the polydopamine-modified basalt fiber-reinforced MC nylon composite material of the present invention, the interfacial shear strength (IFSS) between the modified basalt fiber and the MC nylon matrix is increased by 50-120% compared with the unmodified fiber, the tensile strength is increased by 20-50%, and the flexural strength is increased by 10-40%. Description of the Drawings

[0036] Figure 1 IFSS diagrams of polydopamine-modified basalt fiber-MC nylon in Comparative Example 1 and Examples 1-4.

[0037] Figure 2 Tensile strength diagrams of polydopamine-modified basalt fiber-reinforced MC nylon composite materials in Comparative Example 1 and Examples 1-4.

[0038] Figure 3 Flexural strength diagrams of polydopamine-modified basalt fiber-reinforced MC nylon composite materials in Comparative Example 1 and Examples 1-4.

[0039] Figure 4 Scanning electron microscope diagrams of basalt fibers pulled out from the cross-section of the composite fiber in Comparative Example 1 and Examples 1-4. Detailed Embodiments

[0040] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0041] Example 1

[0042] A preparation method of a polydopamine-modified basalt fiber-reinforced MC nylon composite material in this example includes the following steps:

[0043] S1. Put the basalt fiber into a Soxhlet extractor, add an appropriate amount of acetone for desizing treatment, heat to 85°C to reflux the acetone for 12 h. After the reflux ends, wash the desized basalt fiber in deionized water several times, and put it into a blast drying oven at 80°C for drying for 4 h.

[0044] S2. Put 100 g of the desized basalt fiber into 1 L of deionized water, add dopamine hydrochloride at a concentration of 1 g / L, add Tris buffer at a concentration of 0.01 mol / L (1.21 g / L), and control the environmental pH value to be about 8.5. Turn on the stirring device and stir at 25°C for 24 h to obtain the modified basalt fiber.

[0045] S3. Place the modified basalt fiber in a mold and preheat the mold to 180 °C. Put the caprolactam monomer into a vacuum device, heat it up to 150 °C to melt the caprolactam. Turn on the vacuum pump and the stirring device to keep the reaction device at a vacuum degree of 0.1 MPa. The vacuum pump runs for 20 min until no more bubbles emerge from the caprolactam melt, then extract the water molecules in the caprolactam melt and stop the operation of the vacuum pump. Cool the caprolactam melt to 110 °C, add 0.2 wt% catalyst NaOH, and heat it up to 150 °C. Turn on the vacuum pump and the stirring device to keep the reaction device at a vacuum degree of 0.1 MPa. The vacuum pump runs for 20 min until no more bubbles emerge from the caprolactam melt, then extract the water molecules generated in the reaction in the caprolactam melt and stop the operation of the vacuum pump. Add 0.6 wt% co-catalyst TDI, stir for 1 min, and then pour the melt into a mold containing modified basalt fiber (20 wt%) for casting. The melt reacts in the mold for 60 min and is cooled slowly.

[0046] S4. Place the composite material after polymerization in a water bath, heat it up to 80 °C, and heat for 2 h. Then dry the composite material at 60 °C for 12 h in an environment with a vacuum degree of 0.1 MPa to obtain the polydopamine-modified basalt fiber reinforced MC nylon composite material.

[0047] Example 2

[0048] A preparation method of a polydopamine-modified basalt fiber reinforced MC nylon composite material in this example includes the following steps

[0049] S1. Place the basalt fiber in a Soxhlet extractor, add an appropriate amount of acetone for desizing treatment, heat it up to 85 °C to reflux the acetone for 12 h. After the reflux ends, wash the desized basalt fiber in deionized water several times, and dry it in a forced-air oven at 80 °C for 4 h.

[0050] S2. Place 100 g of the desized basalt fiber in 1 L of deionized water, add dopamine hydrochloride at a concentration of 2 g / L, add Tris buffer at a concentration of 0.01 mol / L (1.21 g / L), and control the environmental pH value to be about 8.5. Turn on the stirring device and stir at 25 °C for 24 h to obtain the modified basalt fiber.

[0051] S3. Place the modified basalt fibers into a mold and preheat the mold to 180 °C. Put the caprolactam monomer into a vacuum device, heat it up to 150 °C to melt the caprolactam. Turn on the vacuum pump and the stirring device to keep the reaction device at a vacuum degree of 0.1 MPa. Run the vacuum pump for 20 min until no more bubbles emerge from the caprolactam melt, then extract the water molecules in the caprolactam melt and stop the operation of the vacuum pump. Cool the caprolactam melt to 110 °C, add 0.2 wt% catalyst NaOH, and heat it up to 150 °C. Turn on the vacuum pump and the stirring device to keep the reaction device at a vacuum degree of 0.1 MPa. Run the vacuum pump for 20 min until no more bubbles emerge from the caprolactam melt, then extract the water molecules generated during the reaction in the caprolactam melt and stop the operation of the vacuum pump. Add 0.6 wt% co-catalyst TDI, stir for 1 min, and then pour the melt into the mold containing the modified basalt fibers (20 wt%) for casting. Let the melt react in the mold for 60 min and cool down slowly.

[0052] S4. Place the composite material after polymerization into a water bath, heat it up to 80 °C, and heat for 2 h. Then dry the composite material in an environment with a vacuum degree of 0.1 MPa at 60 °C for 12 h to obtain the polydopamine-modified basalt fiber-reinforced MC nylon composite material.

[0053] Example 3

[0054] A preparation method of a polydopamine-modified basalt fiber-reinforced MC nylon composite material in this example includes the following steps

[0055] S1. Place the basalt fibers into a Soxhlet extractor, add an appropriate amount of acetone for desizing treatment, heat it up to 85 °C to reflux the acetone for 12 h. After the reflux ends, wash the desized basalt fibers in deionized water several times, and dry them in a forced-air oven at 80 °C for 4 h.

[0056] S2. Place 100 g of the desized basalt fibers into 1 L of deionized water, add dopamine hydrochloride at a concentration of 3 g / L, add Tris buffer at a concentration of 0.01 mol / L (1.21 g / L), and control the environmental pH value to be about 8.5. Turn on the stirring device and stir at 25 °C for 24 h to obtain the modified basalt fibers.

[0057] S3. Place the modified basalt fibers in a mold and preheat the mold to 180 °C. Put the caprolactam monomer into a vacuum device, heat it up to 150 °C to melt the caprolactam. Turn on the vacuum pump and the stirring device to keep the reaction device at a vacuum of 0.1 MPa. The vacuum pump runs for 20 min until no more bubbles emerge from the caprolactam melt, then extract the water molecules in the caprolactam melt and stop the operation of the vacuum pump. Cool the caprolactam melt to 110 °C, add 0.2 wt% catalyst NaOH, and heat it up to 150 °C. Turn on the vacuum pump and the stirring device to keep the reaction device at a vacuum of 0.1 MPa. The vacuum pump runs for 20 min until no more bubbles emerge from the caprolactam melt, then extract the water molecules generated during the reaction in the caprolactam melt and stop the operation of the vacuum pump. Add 0.6 wt% co-catalyst TDI, stir for 1 min, and then pour the melt into the mold containing modified basalt fibers (20 wt%) for casting. The melt reacts in the mold for 60 min and is cooled slowly.

[0058] S4. Place the polymerized composite material in a water bath, heat it up to 80 °C, and heat for 2 h. Then dry the composite material at 60 °C for 12 h under a vacuum of 0.1 MPa to obtain the polydopamine-modified basalt fiber reinforced MC nylon composite material.

[0059] Example 4

[0060] A preparation method of a polydopamine-modified basalt fiber reinforced MC nylon composite material in this example includes the following steps

[0061] S1. Place the basalt fibers in a Soxhlet extractor, add an appropriate amount of acetone for desizing treatment, heat to 85 °C to reflux the acetone for 12 h. After the reflux ends, wash the desized basalt fibers in deionized water several times, and dry them in a forced-air oven at 80 °C for 4 h.

[0062] S2. Put 100 g of desized basalt fibers into 1 L of deionized water, add dopamine hydrochloride at a concentration of 4 g / L, add Tris buffer at a concentration of 0.01 mol / L (1.21 g / L), and control the environmental pH value to be about 8.5. Turn on the stirring device and stir at 25 °C for 24 h to obtain modified basalt fibers.

[0063] S3. Place the modified basalt fiber into a mold and preheat the mold to 180°C. Put the caprolactam monomer into a vacuum device, heat it up to 150°C to melt the caprolactam. Turn on the vacuum pump and the stirring device to keep the reaction device at a vacuum degree of 0.1 MPa. Run the vacuum pump for 20 min until no more bubbles emerge from the caprolactam melt, then extract the water molecules in the caprolactam melt and stop the operation of the vacuum pump. Cool the caprolactam melt to 110°C, add 0.2 wt% of the catalyst NaOH, and heat it up to 150°C. Turn on the vacuum pump and the stirring device to keep the reaction device at a vacuum degree of 0.1 MPa. Run the vacuum pump for 20 min until no more bubbles emerge from the caprolactam melt, then extract the water molecules generated during the reaction in the caprolactam melt and stop the operation of the vacuum pump. Add 0.6 wt% of the co-catalyst TDI, stir for 1 min, and then pour the melt into the mold containing the modified basalt fiber (20 wt%) for casting. Let the melt react in the mold for 60 min and cool down slowly.

[0064] S4. Place the composite material after polymerization into a water bath, heat it up to 80°C, and heat for 2 h. Then dry the composite material at 60°C for 12 h under a vacuum degree of 0.1 MPa to obtain the polydopamine-modified basalt fiber reinforced MC nylon composite material.

[0065] Comparative Example 1

[0066] The preparation method of a polydopamine-modified basalt fiber reinforced MC nylon composite material in this example includes the following steps

[0067] S1. Place the basalt fiber into a Soxhlet extractor, add an appropriate amount of acetone for desizing treatment, heat it up to 85°C to reflux the acetone for 12 h. After the reflux ends, wash the desized basalt fiber with deionized water several times, and then dry it in a forced-air oven at 80°C for 4 h.

[0068] S2. This step does not modify the desized basalt fiber.

[0069] S3. Place the basalt fiber into a mold and preheat the mold to 180 °C. Put the caprolactam monomer into a vacuum device, heat it up to 150 °C to melt the caprolactam. Turn on the vacuum pump and the stirring device to keep the reaction device at a vacuum degree of 0.1 MPa. The vacuum pump runs for 20 min until no more bubbles emerge from the caprolactam melt, then extract the water molecules in the caprolactam melt and stop the operation of the vacuum pump. Cool the caprolactam melt to 110 °C, add 0.2 wt% of the catalyst NaOH, and heat it up to 150 °C. Turn on the vacuum pump and the stirring device to keep the reaction device at a vacuum degree of 0.1 MPa. The vacuum pump runs for 20 min until no more bubbles emerge from the caprolactam melt, then extract the water molecules generated during the reaction in the caprolactam melt and stop the operation of the vacuum pump. Add 0.6 wt% of the co-catalyst TDI, stir for 1 min, and then pour the melt into a mold containing basalt fiber (20 wt%) for casting. The melt reacts in the mold for 60 min and is cooled slowly.

[0070] S4. Place the composite material after polymerization into a water bath, heat it up to 80 °C, and heat for 2 h. Then dry the composite material at 60 °C for 12 h under a vacuum degree of 0.1 MPa to obtain the polydopamine-modified basalt fiber reinforced MC nylon composite material.

[0071] Performance test:

[0072] Take the modified basalt fibers in Examples 1 to 4 and Comparative Example 1 to conduct the interfacial shear strength (IFSS) test between the modified fiber and the MC nylon matrix. The results are as Figure 1 shown.

[0073] Take the polydopamine-modified basalt fiber reinforced MC nylon composite materials in Examples 1 to 4 and Comparative Example 1 to conduct the tensile strength test. The specimen standard refers to "Test Method for Tensile Properties of Fiber Reinforced Plastics" (GB / T 1447 - 2005). The results are as Figure 2 shown.

[0074] Take the polydopamine-modified basalt fiber reinforced MC nylon composite materials in Examples 1 to 4 and Comparative Example 1 to conduct the flexural strength test. The specimen standard refers to "Test Method for Flexural Properties of Fiber Reinforced Plastics" (GB / T 1449 - 2005). The results are as Figure 3 shown.

[0075] Take the polydopamine-modified basalt fiber reinforced MC nylon composite materials in Examples 1 to 4 and Comparative Example 1, and observe the fibers at the failure cross-section by scanning electron microscopy. The results are as Figure 4 shown.

[0076] As Figure 2 and Figure 3As shown, in Comparative Example 1, polydopamine modification was not carried out, and the tensile strength and flexural strength of the basalt fiber / MC nylon composite prepared in Comparative Example 1 were the lowest. In the order of Example 1, Example 2, Example 3, and Example 4, as the dopamine concentration increased and the content of the polydopamine coating increased, the tensile strength and flexural strength of the basalt fiber / MC nylon composite gradually increased. The tensile strength increased by 19 - 47%, and the flexural strength increased by 16 - 33%. This indicates that in the preparation method of the embodiments of the present application, through the modification of the polydopamine coating, the mechanical properties of the basalt fiber / MC nylon were effectively improved. As Figure 1 and Figure 4 shown, in Comparative Example 1, polydopamine modification was not carried out, and the IFSS of the basalt fiber and MC nylon prepared in Comparative Example 1 was the lowest, and the least amount of nylon matrix was carried out by the pulled-out fiber at the failure interface. In the order of Example 1, Example 2, Example 3, and Example 4, as the dopamine concentration increased, the IFSS of the modified basalt fiber and MC nylon gradually increased, and it could be increased by 40 - 127%. It is proved that in the basalt fiber / MC nylon composite, the addition of the polydopamine coating effectively improves the interfacial properties and mechanical properties of the basalt fiber / MC nylon composite.

[0077] The above embodiments only represent several implementation manners of the present application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the patent scope of the present application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several deformations and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A polydopamine-modified basalt fiber-reinforced MC nylon composite material, characterized in that, The composite material comprises the following components: 15 - 30 parts by mass of modified basalt fiber; 70 - 85 parts by mass of MC nylon matrix; Wherein, the modified basalt fiber comprises desized basalt fiber and a modifier, and the weight ratio of the desized basalt fiber to the modifier is 100:1 - 5; the modifier comprises at least one of polydopamine, KH550, KH560, and PEG.

2. The polydopamine-modified basalt fiber-reinforced MC nylon composite material according to claim 1, wherein, The viscosity-average molecular weight of the MC nylon matrix is 45000 - 75000, and the monomer conversion rate is 95 - 99%.

3. The polydopamine-modified basalt fiber reinforced MC nylon composite material according to claim 1, wherein, The catalyst used for preparing the MC nylon matrix is sodium caprolactamate, NaH or NaOH, and the co-catalyst is TDI or MDI.

4. The polydopamine-modified basalt fiber reinforced MC nylon composite material according to claim 1, characterized in that, When preparing the MC nylon matrix, the catalyst dosage is 0.1 - 0.3 wt%, and the co-catalyst dosage is 0.5 wt% - 0.7 wt%.

5. The polydopamine-modified basalt fiber-reinforced MC nylon composite material according to claim 1, characterized in that The polymerization temperature of the MC nylon matrix is 150 - 190 °C, and the polymerization time is 45 - 120 min.

6. The polydopamine-modified basalt fiber reinforced MC nylon composite material according to claim 1, wherein, The modified basalt fiber is modified desized basalt fiber; and the content of the surface modifier of the basalt fiber is 1 - 5 wt%, and the modifier is polydopamine.

7. The polydopamine-modified basalt fiber reinforced MC nylon composite material according to claim 6, wherein, The desizing methods of the desized basalt fiber include heat desizing and acetone desizing. The heat desizing conditions are 300 - 450 °C and 0.5 - 4 h, and the acetone desizing conditions are refluxing at 70 - 90 °C for 1 - 12 h.

8. The polydopamine-modified basalt fiber reinforced MC nylon composite material according to claim 1, characterized in that, The modified basalt fiber is prepared according to the following method: (1) Desize the basalt fiber by heat desizing or acetone desizing, wash it with deionized water and then dry it; (2) Put the desized basalt fiber obtained in step (1) into a hydrochloric acid dopamine-Tris solution and stir; (3) Dry the modified basalt fiber obtained in step (2) to obtain the modified basalt fiber.

9. The polydopamine-modified basalt fiber reinforced MC nylon composite material according to claim 8, characterized in that, In step (2), the stirring time is 12 - 48 h, the concentration of hydrochloric acid dopamine is 1 - 5 g / L, and the Tris concentration is 0.008 - 0.012 mol / L.

10. A method for preparing the polydopamine-modified basalt fiber reinforced MC nylon composite material according to any one of claims 1-9, characterized in that, It includes the following steps: (1) Desize the basalt fiber, and then add hydrochloric acid dopamine for modification to obtain the modified basalt fiber; (2) Preheat the mold to the polymerization temperature of 150 - 190 °C, and add the obtained modified basalt fiber; (3) Heat the caprolactam monomer to 140 - 155 °C, control the vacuum degree at 0.09 - 0.10 MPa with a vacuum pump, and the vacuum pump pumps for 15 - 30 min; (4) Add a catalyst with a dosage of 0.1 - 0.3 wt% to the caprolactam obtained in step (3), and again control the vacuum degree at 0.09 - 0.10 MPa with a vacuum pump, and the vacuum pump pumps for 15 - 30 min; (5) Add a co-catalyst with a dosage of 0.5 - 0.7 wt% to the caprolactam obtained in step (4), stir evenly and then pour it into the mold containing the modified basalt fiber; the dosage of the modified basalt fiber is 15 - 30 wt%; (6) After polymerizing for 45 - 120 min, cool it, and perform post-treatment in a water bath or oil bath at 70 - 90 °C for 1 - 5 h.

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