A liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite material and its preparation method

Abstract

The present invention relates to the technical field of toughening epoxy resins. In order to solve the problems of poor toughness and aging resistance of epoxy resins after curing in the prior art, a liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite material is disclosed, which comprises the following components by weight: 60 - 100 parts of epoxy resin, 10 - 25 parts of curing agent, 0.25 - 1 part of catalyst, 20 - 40 parts of liquid rubber, 20 - 50 parts of modified silicon carbide, 0.2 - 1 part of antioxidant, and 0.2 - 1 part of ultraviolet absorber. The modified liquid rubber and silicon carbide form a spatially uniform and rigid-flexible dispersed structure in the epoxy resin, and have excellent interfacial bonding force. The present invention can effectively improve the wear resistance, mechanical properties and aging resistance of the epoxy resin after curing.

Description

Technical Field

[0001] The present invention relates to the technical field of toughening epoxy resins, and particularly relates to a liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite material and a preparation method thereof. Background Art

[0002] Epoxy resin is one of the most widely used resin systems, and has the advantages of flexible processing, good dimensional stability after curing, high mechanical strength, excellent electrical insulation and heat resistance. In recent years, it has been widely used in the fields of aerospace, ships, buildings, power equipment, sports equipment, etc. In the field of power equipment, epoxy resin can be used as the material for suspension fittings. The suspension fittings are mounted on the line. Under the action of strong winds outdoors, the power fittings will shake and rub against the line, resulting in wear of the power fittings and premature failure. Therefore, there are high requirements for the wear resistance of epoxy resin. At the same time, epoxy resin has problems such as brittleness, low toughness, and easy fatigue aging. Therefore, developing a technology to improve the wear resistance, toughness and aging resistance of cured epoxy resin has important application value.

[0003] For example, the "Epoxy Resin Toughening Modifier for Composites and Epoxy Resin Toughening Modification Method" disclosed in the Chinese patent literature, with the publication number of CN108864658A, the epoxy resin toughening modifier for composites of the present invention is composed of 75% by mass of bisphenol A epoxy resin and 25% by mass of nano core-shell rubber. This method has a certain toughening effect, but it cannot improve the heat aging resistance and friction resistance of epoxy resin materials. Summary of the Invention

[0004] In order to overcome the problems of poor wear resistance, toughness and aging resistance of cured epoxy resin in the prior art, the present invention provides a liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite material. The epoxy resin composite material has good wear resistance and mechanical properties after curing, and has excellent high temperature aging resistance. The present invention also provides a preparation method of a liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite material.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite material, comprising the following weight components: 60-100 parts of epoxy resin, 10-25 parts of curing agent, 0.25-1 part of catalyst, 20-40 parts of liquid rubber, 20-50 parts of modified silicon carbide, 0.2-1 part of antioxidant, and 0.2-1 part of ultraviolet absorber.

[0007] The present invention uses liquid rubber and modified silicon carbide to synergistically enhance the toughness of cured epoxy resin. Silicon carbide can improve the mechanical properties and aging resistance of epoxy resin, reduce the growth of silver streaks, thereby enhancing the toughness of epoxy resin. Silicon carbide can also improve the wear resistance of epoxy resin, enabling it to reduce frictional wear when used to replace electrical hardware and extend its service life. Liquid rubber can improve the toughness of epoxy resin, and its synergistic effect with modified silicon carbide can effectively enhance its toughness while maintaining a relatively high mechanical strength of the epoxy resin curing system.

[0008] Preferably, the preparation steps of the modified silicon carbide include:

[0009] 1) Soak silicon carbide with a particle size of 20 - 500 nm in a mixed solution of concentrated sulfuric acid and hydrogen peroxide for 40 - 120 min, take it out and wash it;

[0010] 2) Heat the washed silicon carbide and tung oil anhydride to 60 - 80 °C and react for 6 - 12 h to obtain modified silicon carbide.

[0011] Tung oil anhydride is grafted onto the surface of silicon carbide through the surface hydroxyl groups of silicon carbide, improving the compatibility between silicon carbide, epoxy resin and liquid rubber. At the same time, it can also form a cross-linked network with liquid rubber, thereby forming a well-dispersed inorganic-organic interface in epoxy resin. Tung oil anhydride also has a certain ability to cure epoxy resin, which can reduce the amount of curing agent used.

[0012] Preferably, in step 2), the mass ratio of silicon carbide to tung oil anhydride is (60 - 80):(20 - 50).

[0013] Preferably, in step 1), the volume ratio of concentrated sulfuric acid to hydrogen peroxide in the mixed solution of concentrated sulfuric acid and hydrogen peroxide is 1:(1 - 5).

[0014] Preferably, the liquid rubber is selected from one or a combination of bifunctional epoxidized polybutadiene rubber, epoxidized nitrile rubber, and epoxidized styrene-butadiene rubber, and its bifunctional groups are one of terminal aldehyde group, terminal hydroxyl group, terminal carboxyl group, terminal oxime group, and terminal primary amine group.

[0015] The epoxidized liquid rubber contains side epoxy groups. Through co-curing, flexible chains are introduced into the epoxy resin to form a special structure of cross-linking between hard and soft chains, increasing the cross-linking density and simultaneously enhancing the toughness of the cured epoxy resin. And it has a relatively high hydroxyl content, which can improve the dispersion effect of liquid rubber in epoxy resin and reduce agglomeration.

[0016] Preferably, the epoxy resin is selected from one of E-51 epoxy resin, E-44 epoxy resin, and hydrogenated epoxy resin.

[0017] Preferably, the curing agent is selected from one or two of modified amine curing agents, low molecular weight polyamide curing agents, imidazole curing agents, phenolic amine curing agents, and anhydride curing agents; the catalyst is selected from one of anhydride catalyst BDMA and aliphatic amine DMP-30.

[0018] Preferably, the antioxidant is selected from one or several combinations of pentaerythritol tetrakis [β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 2,6-di-tert-butyl-p-cresol, octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl) benzene, 2,2'-methylenebis(4-ethyl-6-tert-butylphenol).

[0019] Preferably, the ultraviolet light absorber is selected from one or several combinations of 2-hydroxy-4-n-octyloxybenzophenone, 2-(2'-hydroxy-5'-methylphenyl) benzotriazole, phenyl salicylate, 2,4-dihydroxybenzophenone, 2-(2'-hydroxy-3',5'-di-tert-phenyl)-5-chlorobenzotriazole, and resorcinol monobenzoate.

[0020] A preparation method of a liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite material includes the following steps:

[0021] (1) Mix epoxy resin, liquid rubber, and catalyst, and heat to 90-100°C and stir and react for 2-3 h to obtain a modified epoxy prepolymer;

[0022] (2) Cool the modified epoxy prepolymer to 30-40°C, add a curing agent, modified silicon carbide, antioxidant, and ultraviolet light absorber, and stir evenly to obtain a rubber compound;

[0023] (3) Vacuum degas the rubber compound for 15-20 min, and then pour it into a mold for curing. The curing process is to heat to 75-80°C and keep warm for 2-2.5 h, and then heat to 110-120°C and keep warm for 5-6 h.

[0024] Therefore, the present invention has the following beneficial effects: (1) The modified liquid rubber and silicon carbide form a spatially uniform and rigid-flexible dispersed structure in the epoxy resin, and have excellent interfacial bonding strength; (2) It can effectively improve the wear resistance, mechanical properties, and aging resistance of the cured epoxy resin. Specific Embodiments

[0025] The following further describes the present invention in combination with specific implementation methods.

[0026] Example 1

[0027] A liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite material is prepared by the following steps:

[0028] (1) Silicon carbide with a particle size of 50 nm is immersed in a mixed solution of concentrated sulfuric acid and hydrogen peroxide for 40 min, taken out and washed. 30 g of silicon carbide and 22 g of tung oil anhydride are added to 300 mL of DMF and heated to 80 °C for reaction for 12 h to obtain modified silicon carbide, where the volume ratio of concentrated sulfuric acid to hydrogen peroxide in the mixed solution of concentrated sulfuric acid and hydrogen peroxide is 1:3;

[0029] (2) Weigh 100 g of E-51 epoxy resin in a three-necked flask, add 20 g of bis-hydroxylated epoxidized polybutadiene rubber and 0.35 g of N,N-dimethylbenzylamine catalyst (anhydride catalyst BDMA), stir evenly, heat up to 100 °C, stir at a speed of 4000 r / min for 2 h, and stop the reaction to obtain the modified epoxy resin for use;

[0030] (3) When the above-mentioned modified epoxy prepolymer is cooled to 40 °C, add 25 g of epoxy resin 593 curing agent, 0.5 g of antioxidant 1010, 30 g of modified silicon carbide and 0.5 g of ultraviolet absorber, stir evenly to obtain the rubber compound;

[0031] (4) Vacuum degas the rubber compound for 15 min, then pour it into a standard mold, heat it to 80 °C and keep it warm for 2 h, and then heat it to 120 °C and keep it warm for 5 h to complete curing.

[0032] Example 2

[0033] A liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite material is prepared by the following steps:

[0034] (1) Silicon carbide with a particle size of 50 nm is immersed in a mixed solution of concentrated sulfuric acid and hydrogen peroxide for 40 min, taken out and washed. 30 g of silicon carbide and 22 g of tung oil anhydride are added to 300 mL of DMF and heated to 80 °C for reaction for 12 h to obtain modified silicon carbide, where the volume ratio of concentrated sulfuric acid to hydrogen peroxide in the mixed solution of concentrated sulfuric acid and hydrogen peroxide is 1:3;

[0035] (2) Weigh 100 g of E-51 epoxy resin in a three-necked flask, add 40 g of bis-hydroxylated epoxidized polybutadiene rubber and 0.35 g of N,N-dimethylbenzylamine catalyst, stir evenly, heat up to 100 °C, stir at a speed of 4000 r / min for 2 h, and stop the reaction to obtain the modified epoxy resin for use;

[0036] (3) When the above-mentioned modified epoxy prepolymer is cooled to 40 °C, add 25 g of epoxy resin 593 curing agent, 0.5 g of antioxidant 1010, 20 g of modified silicon carbide and 0.5 g of ultraviolet absorber, stir evenly to obtain the rubber compound;

[0037] (4) Degas the rubber compound under vacuum for 15 min, then pour it into a standard mold, heat it to 80 °C and keep it warm for 2 h, and then heat it to 120 °C and keep it warm for 5 h to complete curing.

[0038] Example 3

[0039] A liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite material is prepared by the following steps:

[0040] (1) Soak silicon carbide with a particle size of 50 nm in a mixed solution of concentrated sulfuric acid and hydrogen peroxide for 40 min, take it out and wash it. Add 30 g of silicon carbide and 22 g of tung oil anhydride to 300 mL of DMF and heat it to 60 °C and react for 12 h to obtain modified silicon carbide, where the volume ratio of concentrated sulfuric acid to hydrogen peroxide in the mixed solution of concentrated sulfuric acid and hydrogen peroxide is 1:3;

[0041] (2) Weigh 100 g of E-51 epoxy resin in a three-necked flask, add 40 g of bis(aldehyde group) epoxidized polybutadiene rubber and 0.35 g of aliphatic amine DMP-30, stir evenly, raise the temperature to 100 °C, stir at a speed of 4000 r / min for 2 h, and stop the reaction to prepare the modified epoxy resin for use;

[0042] (3) When the above-mentioned modified epoxy prepolymer is cooled to 40 °C, add 25 g of epoxy resin 593 curing agent, 0.5 g of antioxidant 1010, 20 g of modified silicon carbide and 0.5 g of ultraviolet absorber, and stir evenly to obtain the rubber compound;

[0043] (4) Degas the rubber compound under vacuum for 15 min, then pour it into a standard mold, heat it to 80 °C and keep it warm for 2 h, and then heat it to 120 °C and keep it warm for 5 h to complete curing.

[0044] Example 4

[0045] A liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite material is prepared by the following steps:

[0046] (1) Soak silicon carbide with a particle size of 200 nm in a mixed solution of concentrated sulfuric acid and hydrogen peroxide for 40 min, take it out and wash it. Add 30 g of silicon carbide and 15 g of tung oil anhydride to 300 mL of DMF and heat it to 80 °C and react for 12 h to obtain modified silicon carbide, where the volume ratio of concentrated sulfuric acid to hydrogen peroxide in the mixed solution of concentrated sulfuric acid and hydrogen peroxide is 1:3;

[0047] (2) Weigh 100 g of E-51 epoxy resin in a three-necked flask, add 20 g of epoxidized nitrile rubber and 0.35 g of N,N-dimethylbenzylamine catalyst, stir evenly, heat up to 100 °C, stir at a speed of 4000 r / min for 2 h, stop the reaction, and prepare the modified epoxy resin for use;

[0048] (3) When the above-mentioned modified epoxy prepolymer is cooled to 40 °C, add 25 g of epoxy resin 593 curing agent, 0.5 g of antioxidant 1010, 30 g of modified silicon carbide and 0.5 g of ultraviolet absorber, stir evenly to obtain the rubber compound;

[0049] (4) Degas the rubber compound under vacuum for 15 min, then pour it into a standard mold, heat it to 80 °C and keep it warm for 2 h, then heat it to 120 °C and keep it warm for 5 h to complete curing.

[0050] Comparative Example 1

[0051] An epoxy resin material is prepared by the following steps:

[0052] (1) Weigh 150 g of E-51 epoxy resin in a three-necked flask, add 0.35 g of N,N-dimethylbenzylamine catalyst, stir evenly, heat up to 100 °C, stir at a speed of 4000 r / min for 2 h, stop the reaction, and prepare the modified epoxy resin for use;

[0053] (2) When the above-mentioned modified epoxy prepolymer is cooled to 40 °C, add 25 g of epoxy resin 593 curing agent, 0.5 g of antioxidant 1010 and 0.5 g of ultraviolet absorber, stir evenly to obtain the rubber compound;

[0054] (3) Degas the rubber compound under vacuum for 15 min, then pour it into a standard mold, heat it to 80 °C and keep it warm for 2 h, then heat it to 120 °C and keep it warm for 5 h to complete curing.

[0055] Comparative Example 2

[0056] A liquid rubber toughened epoxy resin composite material is prepared by the following steps:

[0057] (1) Weigh 100 g of E-51 epoxy resin in a three-necked flask, add 50 g of bis-hydroxylated epoxidized polybutadiene rubber and 0.35 g of N,N-dimethylbenzylamine catalyst, stir evenly, heat up to 100 °C, stir at a speed of 4000 r / min for 2 h, stop the reaction, and prepare the modified epoxy resin for use;

[0058] (2) When the above-mentioned modified epoxy prepolymer is cooled to 40 °C, add 25 g of epoxy resin 593 curing agent, 0.5 g of antioxidant 1010 and 0.5 g of ultraviolet absorber, stir evenly to obtain the rubber compound;

[0059] (3) Degas the rubber compound under vacuum for 15 min, then pour it into a standard mold, heat it to 80 °C and keep it warm for 2 h, then heat it to 120 °C and keep it warm for 5 h to complete curing.

[0060] Comparative Example 3 A modified silicon carbide toughened epoxy resin composite material is prepared by the following steps:

[0061] (1) Immerse silicon carbide with a particle size of 50 nm in a mixed solution of concentrated sulfuric acid and hydrogen peroxide for 40 min, take it out and wash it. Add 30 g of silicon carbide and 22 g of tung oil anhydride to 300 mL of DMF, heat it to 80 °C and react for 12 h to obtain modified silicon carbide, where the volume ratio of concentrated sulfuric acid to hydrogen peroxide in the mixed solution of concentrated sulfuric acid and hydrogen peroxide is 1:3;

[0062] (2) Weigh 100 g of E-51 epoxy resin in a three-necked flask, add 0.35 g of N,N-dimethylbenzylamine catalyst, stir evenly, raise the temperature to 100 °C, stir at a speed of 4000 r / min for 2 h, and stop the reaction to obtain modified epoxy resin for use;

[0063] (3) When the above-mentioned modified epoxy prepolymer is cooled to 40 °C, add 25 g of epoxy resin 593 curing agent, 0.5 g of antioxidant 1010, 50 g of modified silicon carbide and 0.5 g of ultraviolet absorber, and stir evenly to obtain a rubber compound;

[0064] (4) Degas the rubber compound under vacuum for 15 min, then pour it into a standard mold, heat it to 80 °C and keep it warm for 2 h, then heat it to 120 °C and keep it warm for 5 h to complete curing.

[0065] Comparative Example 4

[0066] A liquid rubber and silicon carbide synergistically toughened epoxy resin composite material is prepared by the following steps:

[0067] (1) Weigh 100 g of E-51 epoxy resin in a three-necked flask, add 20 g of bis-hydroxylated epoxidized polybutadiene rubber and 0.35 g of N,N-dimethylbenzylamine catalyst, stir evenly, raise the temperature to 100 °C, stir at a speed of 4000 r / min for 2 h, and stop the reaction to obtain modified epoxy resin for use;

[0068] (2) When the above-mentioned modified epoxy prepolymer is cooled to 40 °C, add 25 g of epoxy resin 593 curing agent, 0.5 g of antioxidant 1010, 30 g of silicon carbide with a particle size of 50 nm and 0.5 g of ultraviolet absorber, and stir evenly to obtain a rubber compound;

[0069] (3) Degas the rubber compound under vacuum for 15 min, then pour it into a standard mold, heat it to 80 °C and keep it warm for 2 h, then heat it to 120 °C and keep it warm for 5 h to complete curing.

[0070] The materials obtained from the above examples and comparative examples were subjected to the following performance tests:

[0071] (1) Abrasion resistance test

[0072] Referring to GB / T 9867-2008, the samples prepared in the examples and comparative examples were tested, with at least 3 parallel samples set, and the average value was recorded;

[0073] (2) Mechanical property test

[0074] Referring to GB / T 2567-2008, the samples prepared in the examples and comparative examples were tested at room temperature, with at least 3 parallel samples set, and the average value was recorded;

[0075] (3) High-temperature aging

[0076] The samples prepared in the examples and comparative examples were dried at 70 °C for 3 h, weighed, then placed in 250 °C for 720 h for high-temperature aging test, and finally weighed after drying at 70 °C for 3 h. At least 3 parallel samples were set, and the mass change rate was calculated and the average value was recorded;

[0077] (4) Electrical property test

[0078] The volume and surface resistivity were tested referring to GB / T 1692-2008;

[0079] The results are shown in the following table.

[0080]

[0081]

[0082] As can be seen from the above table, the abrasion resistance, tensile strength, flexural strength, impact strength and high-temperature aging indexes of Examples 1-4 are better than those of Comparative Example 1, which indicates that the present invention significantly improves the abrasion resistance, toughness and high-temperature aging resistance of the cured epoxy resin.

[0083] The toughness and high-temperature aging resistance of Example 1 are better than those of Comparative Example 2 and Comparative Example 3, which indicates that the liquid rubber and the modified silicon carbide have a synergistic effect, and its toughening effect is better than that of using liquid rubber or modified silicon carbide alone. Among them, the abrasion resistance of Comparative Example 3 is better than that of Comparative Example 2 but weaker than that of Example 1, which indicates that silicon carbide can improve the wear resistance of epoxy resin, and the cross-linked network formed by liquid rubber and silicon carbide can further improve the abrasion resistance of epoxy resin.

[0084] In Comparative Example 4, unmodified silicon carbide was used, and its compatibility with epoxy resin and liquid rubber is much lower than that of modified silicon carbide. Therefore, the toughening effect is weaker than that of Example 1, and at the same time, the wear resistance decreases.

Claims

1. A preparation method of a liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite material, characterized in that, It includes the following steps: (1) By weight, 60 - 100 parts of epoxy resin, 20 - 40 parts of liquid rubber, and 0.25 - 1 part of catalyst are mixed, and the temperature is raised to 90 - 100 °C and stirred for reaction for 2 - 3 h to obtain a modified epoxy prepolymer; the liquid rubber is selected from one or a combination of bis - terminated functionalized epoxidized polybutadiene rubber, epoxidized nitrile rubber, and epoxidized styrene - butadiene rubber, and its bis - terminal functional groups are one of terminal aldehyde group, terminal hydroxyl group, terminal carboxyl group, terminal oxime group, and terminal primary amine group; (2) The modified epoxy prepolymer is cooled to 30 - 40 °C, 10 - 25 parts of curing agent, 20 - 50 parts of modified silicon carbide, 0.2 - 1 part of antioxidant, and 0.2 - 1 part of ultraviolet absorber are added, and stirred evenly to obtain a rubber compound; (3) The rubber compound is vacuum - degassed for 15 - 20 min, and then poured into a mold for curing. The curing process is to heat to 75 - 80 °C and keep warm for 2 - 2.5 h, and then heat to 110 - 120 °C and keep warm for 5 - 6 h; The preparation steps of the modified silicon carbide include: 1) Silicon carbide with a particle size of 20 - 500 nm is immersed in a mixed solution of concentrated sulfuric acid and hydrogen peroxide for 40 - 120 min, taken out and washed; 2) The washed silicon carbide and tung oil anhydride are heated to 60 - 80 °C and reacted for 6 - 12 h to obtain modified silicon carbide.

2. The preparation method of a liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite according to claim 1, characterized in that, In step 2), the mass ratio of silicon carbide to tung oil anhydride is (60 - 80):(20 - 50).

3. The preparation method of a liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite material according to claim 1 or 2, characterized in that, In step 1), the volume ratio of concentrated sulfuric acid to hydrogen peroxide in the mixed solution of concentrated sulfuric acid and hydrogen peroxide is 1:(1 - 5).

4. The preparation method of a liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite according to claim 1, characterized in that, The liquid rubber is selected from one of bis - terminal hydroxylated epoxidized polybutadiene rubber, bis - terminal aldehyde - functionalized epoxidized polybutadiene rubber, and epoxidized nitrile rubber.

5. The preparation method of a liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite according to claim 1 or 4, characterized in that, The epoxy resin is selected from one of E - 51 epoxy resin, E - 44 epoxy resin, and hydrogenated epoxy resin.

6. The preparation method of a liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite according to claim 1, characterized in that, The curing agent is selected from one or two of modified amine curing agent, low - molecular - weight polyamide curing agent, imidazole - type curing agent, phenolic amine curing agent, and acid anhydride - type curing agent; the catalyst is selected from one of acid anhydride catalyst BDMA and aliphatic amine DMP - 30.

7. The preparation method of a liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite according to claim 1, characterized in that The antioxidant is selected from one or a combination of pentaerythritol tetra[β - (3,5 - di - tert - butyl - 4 - hydroxyphenyl)propionate], 2,6 - di - tert - butyl - p - cresol, octadecyl β(3,5 - di - tert - butyl - 4 - hydroxyphenyl)propionate, 1,1,3 - tris(2 - methyl - 4 - hydroxy - 5 - tert - butylphenyl)butane, 1,3,5 - trimethyl - 2,4,6 - tris(3,5 - di - tert - butyl - 4 - hydroxybenzyl)benzene, and 2,2'- methylene - bis(4 - ethyl - 6 - tert - butylphenol).

8. The preparation method of a liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite according to claim 1, characterized in that, The ultraviolet absorber is selected from one or a combination of 2 - hydroxy - 4 - n - octyloxybenzophenone, 2 - (2ˊ - hydroxy - 5ˊ - methylphenyl)benzotriazole, phenyl salicylate, 2,4 - dihydroxybenzophenone, 2 - (2’ - hydroxy - 3’,5’ - di - tert - phenyl) - 5 - chlorobenzotriazole, and resorcinol monobenzoate.

9. A liquid rubber and modified silicon carbide synergistically toughened epoxy resin composite material, characterized in that, It is prepared by using the preparation method according to any one of claims 1 - 8.

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