Flame-retardant rubber material for cable sealing element and preparation method of flame-retardant rubber material

Abstract

The invention relates to the technical field of cable fitting preparation, in particular to a flame-retardant rubber material for a cable sealing element and a preparation method of the flame-retardant rubber material, and the flame-retardant rubber material comprises the following components in parts by weight: 85-100 parts of hydrogenated nitrile rubber, 3-5 parts of a vulcanizing agent, 2-3 parts of a vulcanizing aid, 6-8 parts of a stabilizer, 15-25 parts of a toughening agent, 6-8 parts of modified glass fiber and 20-25 parts of a flame retardant. According to the flame-retardant rubber material prepared by the technical scheme, the waterproof and oil-proof performance is enhanced, meanwhile, the excellent flame-retardant characteristic is endowed, the defect of a traditional cable sealing element material in the flame-retardant performance aspect is overcome, and the requirement of modern electrical equipment for a high-safety sealing material is met.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cable accessory preparation, in particular to a flame-retardant rubber material for cable sealing and a preparation method thereof. BACKGROUND

[0002] As a key component in electrical equipment, cable sealing is mainly used to prevent moisture, gas and other harmful substances from entering the inside of the cable, ensuring the safe and reliable operation of the cable system. With the rapid development of modern power, communication and automation technology, the performance requirements of cable sealing are becoming higher and higher, not only need to have excellent sealing performance, mechanical strength and environmental resistance, but also need to have flame retardant, high temperature resistance, anti-aging and other special functions in special application occasions. Rubber material becomes the main material for preparing cable sealing due to its good elasticity, sealing performance and processing performance, but traditional rubber material often can not meet multiple harsh use requirements at the same time, especially in the aspect of flame retardant performance.

[0003] The existing patent CN201910478480.5 provides a flame-retardant explosion-proof rubber material for cable sealing, which includes the following raw materials in a certain weight ratio: including a three-layer structure, from inside to outside, a support rubber layer, an explosion-proof rubber layer, and a flame-retardant rubber layer; using nitrile rubber, chlorobutyl rubber, cis-butadiene rubber, isoprene rubber, and ethylene-propylene-diene rubber as the main rubber material, the cable sealing not only has high air tightness, wear resistance, aging resistance, oil resistance, corrosion resistance and other characteristics, but also has good flame retardance, high elasticity, effective explosion-proof performance, wide temperature range, simple preparation method and low price. However, this technical solution still has certain technical defects: first, the three-layer structure may have interlayer peeling or delamination phenomenon during long-term use, which reduces the waterproof and oil-proof performance, and further affects the overall performance and service life of the sealing; second, the use of multiple different types of rubber can combine the advantages of various rubbers, but also brings problems such as compatibility control difficulty, complex vulcanization matching, and narrow processing process window; in addition, the flame retardant efficiency of the traditional flame retardant system is relatively low, and a high addition amount is needed to achieve the ideal flame retardant effect, which often affects the mechanical properties and processing properties of the rubber material, and it is difficult to achieve the best balance between flame retardant performance and other performances. SUMMARY

[0004] Therefore, the present application provides a flame-retardant rubber material for cable sealing and a preparation method thereof, to solve the problem that the existing flame-retardant rubber material cannot simultaneously consider flame retardant performance and sealing performance.

[0005] The technical scheme of the present application is implemented as follows: the present application provides a flame-retardant rubber material for cable sealing, which comprises the following components in parts by weight: 85-100 parts of hydrogenated nitrile rubber, 3-5 parts of vulcanizing agent, 2-3 parts of vulcanizing aid, 6-8 parts of stabilizer, 15-25 parts of toughening agent, 6-8 parts of modified glass fiber and 20-25 parts of flame retardant.

[0006] In the present application, the hydrogenated nitrile rubber serves as the main material, which has excellent oil resistance, heat resistance and oxidation resistance, providing good basic performance for the sealing; the vulcanizing agent is used in combination with the vulcanizing aid to form a stable three-dimensional crosslinking network structure, ensuring that the material has a suitable vulcanization degree and excellent elastic recovery performance; the addition of the stabilizer effectively prevents the rubber from thermal aging during use, significantly improving the service life of the material; the introduction of the toughening agent improves the toughness and impact resistance of the material, avoiding brittle fracture under mechanical stress; the modified glass fiber forms a firm chemical bond with the rubber matrix, providing excellent reinforcing effect, the pyridine groups on the surface significantly improve the ultraviolet aging resistance, and the fluorine groups form a chemical protective film, comprehensively improving the environmental tolerance; the flame retardant adopts a phosphorus-nitrogen synergistic system, which builds a composite flame-retardant system combining physical barrier and chemical flame retardation by modifying mica powder, achieving efficient and low-addition flame retardation, and synergistically enhancing the modified glass fiber to further improve the overall flame retardation performance. Through the synergistic effect of the above components, the flame-retardant rubber material prepared by the present application not only has the basic properties such as sealing, elasticity and environmental resistance required by traditional cable sealing, but also achieves a major breakthrough in flame-retardant safety, which can meet the long-term stable use requirements of cable sealing in various complex environments under the premise of ensuring safety.

[0007] On the basis of the above technical scheme, preferably, the preparation method of the modified glass fiber comprises: A1, the glass fiber is pretreated and dispersed in an ethanol aqueous solution, an amino silane coupling agent is added, the temperature is raised to 70-80℃, and the reaction is carried out for 12-14h to obtain amino glass fiber; A2, the amino glass fiber is dispersed in a solvent, 5-mercapto-2-pyridine carboxylic acid and dicyclohexyl carbodiimide are added, and the reaction is carried out at 25-40℃ for 12-24h to obtain mercapto glass fiber; A3, the mercapto glass fiber is dispersed in a solvent, 1,1,1-trifluoro-2-trifluoromethyl-4-pentene-2-ol and 2,2-dimethoxy-2-phenyl phenylacetophenone are added, and the reaction is carried out under ultraviolet light at 20-25℃ for 1-2h to obtain modified glass fiber.

[0008] In the present application, in step A1, the amino group is introduced on the surface of the fiber, which provides an active site for the subsequent reaction. At the same time, the modification of the amino silane coupling agent can improve the interfacial compatibility between the inorganic fiber and the organic rubber matrix, effectively reducing the interfacial defects and stress concentration phenomenon. In step A2, the thiol and pyridine groups are introduced on the surface of the fiber through the amidation reaction. The π-π conjugated system of the pyridine group can effectively absorb ultraviolet light and convert harmful ultraviolet energy into heat energy through intramolecular energy transfer, giving the fiber excellent ultraviolet aging resistance. In addition, the weak alkaline property of the pyridine group can also neutralize the acidic substances produced during the aging process of the rubber, further delaying the aging process of the material. In step A3, the fluorine-containing alcohol group is covalently grafted to the surface of the fiber through the thiol-ene reaction, forming a dense "chemical protective film" on the surface of the fiber. This protective film not only prevents the penetration of water molecules and oil molecules, but also effectively prevents the invasion of oxidizing gases such as oxygen and ozone, thereby improving the service performance of the composite material in harsh environments. At the same time, the excellent thermal stability of the fluorine-containing molecule further improves the heat resistance of the modified fiber, forming a synergistic effect with the rubber matrix.

[0009] On the basis of the above technical scheme, preferably, in step A1, the mass ratio of glass fiber to amino silane coupling agent is 1:0.02-0.05, and the amino silane coupling agent is one or more of γ-aminopropyl triethoxysilane and γ-aminopropyl trimethoxysilane.

[0010] On the basis of the above technical scheme, preferably, in step A2, the mass ratio of aminated glass fiber, 5-mercapto-2-pyridine carboxylic acid and dicyclohexyl carbodiimide is 10: (1.5-2.5): (2.0-3.0) On the basis of the above technical scheme, preferably, in step A3, the mass ratio of mercapto glass fiber, 1,1,1-trifluoro-2-trifluoromethyl-4-pentene-2-ol and 2,2-dimethoxy-2-phenyl phenylacetophenone is 10: (2.0-3.0): (0.1-0.2).

[0011] On the basis of the above technical scheme, preferably, the preparation method of the flame retardant comprises: B1, mixing vinyl phosphonic acid, vinyl silane coupling agent and 4-vinyl pyridine in toluene, under nitrogen protection, heating to 60-70℃, adding azobis isobutyronitrile, and keeping warm for 6-8h to obtain a modifier; B2, dispersing mica powder in anhydrous ethanol, adding the modifier, heating to 80-90℃, and keeping warm for 4-6h to obtain modified mica powder.

[0012] In the application, in step B1, the multifunctional copolymer modifier containing phosphorus, silicon and nitrogen is formed by a free radical polymerization reaction, the introduction of vinyl phosphonic acid provides the phosphorus flame retardant function for the modifier, can release phosphonic acid groups in the combustion process, and form a dense carbon layer on the material surface to effectively isolate oxygen and heat transfer; the participation of vinyl silane coupling agent not only provides silane coupling function, but also can form chemical bonding with the rubber matrix to enhance the interfacial bonding force; the copolymerization of 4-vinyl pyridine introduces nitrogen-containing groups to form phosphorus-nitrogen synergistic flame retardant effect with the phosphorus flame retardant, significantly improve the flame retardant efficiency, and the presence of pyridine ring can also form pi-pi interaction with the pyridine groups in the modified glass fiber to enhance the synergistic effect between components. In step B2, the modification agent is firmly loaded on the surface of the mica powder by dehydration condensation reaction, so that the surface of the mica powder has multiple functions such as phosphorus flame retardant, nitrogen flame retardant and silane coupling, which not only significantly improves the flame retardant efficiency, but also improves the compatibility of the filler and the rubber matrix; in addition, the lamellar structure of the mica powder can form a physical barrier layer in the combustion process, and cooperates with the surface chemical flame retardant groups to construct a composite flame retardant system combining physical barrier and chemical flame retardant, and realizes high-efficiency and low-addition flame retardant effect.

[0013] On the basis of the above technical scheme, preferably, in step B1, the mass ratio of vinyl phosphonic acid, vinyl silane coupling agent, 4-vinyl pyridine and azobisisobutyronitrile is 9-11:7-9:5-7:0.1-0.3; the vinyl silane coupling agent is 3-mercaptopropyl trimethoxysilane or 3-mercaptopropyl triethoxysilane.

[0014] On the basis of the above technical scheme, preferably, in step B2, the mass ratio of mica powder and modification agent is 100:10-14.

[0015] On the basis of the above technical scheme, preferably, the toughening agent is epoxy soybean oil, dioctyl phthalate or dioctyl adipate; the vulcanizing agent is one or more of di-tert-butyl peroxide, dicumyl peroxide or 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, the vulcanizing aid is zinc oxide; and the stabilizer is magnesium oxide or magnesium hydroxide.

[0016] The application also provides a preparation method of the flame-retardant rubber material for cable seals. The hydrogenated nitrile rubber and the stabilizer are added to a banbury mixer for plasticizing, and plasticized for 5-10 min at 60-80 DEG C; the temperature is raised to 90-110 DEG C, the stabilizer, the vulcanizing aid, the toughening agent, the modified glass fiber and the flame retardant are added, and mixed for 10-15 min to ensure that the inorganic fillers and the aids are fully and uniformly dispersed in the rubber matrix, then the vulcanizing agent is added, and dynamically vulcanized for 10-20 min to obtain the composite material.

[0017] The flame-retardant rubber material for cable seal and the preparation method thereof have the following beneficial effects relative to the prior art: (1) The flame-retardant rubber material is prepared by using hydrogenated nitrile rubber as a main material, cooperating with a vulcanizing agent, a vulcanizing aid, a stabilizer, a toughening agent, modified glass fiber and a flame retardant, through the synergistic effect of the components, the flame-retardant rubber material significantly improves the flame-retardant safety performance on the basis of maintaining good sealing performance, elasticity and environmental resistance. The excellent oil resistance and heat resistance of the hydrogenated nitrile rubber provide stable basic performance for the material, the vulcanization system ensures the appropriate crosslinking density and elastic recovery capacity, the addition of the stabilizer and the toughening agent further improves the service life and mechanical properties of the material, and the introduction of the modified glass fiber and the flame retardant enhances the waterproof and oil-proof performance of the material while imparting excellent flame-retardant properties, solving the deficiency of traditional cable seal materials in flame-retardant performance and meeting the demand of modern electrical equipment for high-safety sealing materials.

[0018] (2) The modified glass fiber significantly improves the interfacial bonding performance of the glass fiber and the rubber matrix, and also improves the waterproof, oil-proof and anti-aging performance of the flame-retardant rubber. The modification of the amino silane coupling agent reduces the polarity of the fiber surface and improves the compatibility with the organic matrix; the pyridine groups introduced on the fiber surface through the amidation reaction have excellent ultraviolet light absorption capacity, which can effectively prevent the degradation of the rubber matrix caused by ultraviolet radiation, and significantly improve the ultraviolet aging resistance of the material; the grafting of the fluorine-containing groups on the fiber surface forms a dense chemical protective layer, effectively preventing the penetration of water, oil and oxidizing gas, and comprehensively improving the service stability of the composite material in harsh environments while maintaining good processing performance.

[0019] (3) The flame retardant of the present application adopts a phosphorus-nitrogen synergistic flame-retardant mechanism, combines the modified mica powder with the multifunctional flame-retardant groups loaded on the surface, and constructs a composite flame-retardant system combining physical barrier and chemical flame retardation. The vinyl phosphonic acid in the modifier forms a dense carbon layer during combustion, effectively insulating oxygen and heat transfer; the nitrogen-containing groups provided by 4-vinyl pyridine form a synergistic effect with phosphorus-based flame retardants, significantly improving the flame-retardant efficiency; the presence of vinyl silane coupling agent enhances the interfacial bonding force between the flame retardant and the rubber matrix, avoiding the phase separation phenomenon in the traditional flame retardant adding process. The flame-retardant system can achieve excellent flame-retardant effect at a lower addition amount, effectively solving the problem of mechanical property decline caused by high addition amount of traditional flame retardants, and achieving a good balance between flame-retardant performance and other properties. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the scope of protection of the present application.

[0021] In the present application, the glass fiber is purchased from Taian Songze Composite Material Co., Ltd., with a diameter of 13 μm and a length of 6 mm; the mica powder is purchased from Shijiazhuang Fenghua Mining Products Co., Ltd., with a particle size of 100 mesh.

[0022] Example 1 The present embodiment provides a flame-retardant rubber material for cable seal, which comprises the following components in parts by weight: 93 parts of hydrogenated nitrile rubber, 4 parts of dicumyl peroxide, 2.5 parts of zinc oxide, 7 parts of magnesium oxide, 20 parts of epoxy soybean oil, 7 parts of modified glass fiber and 23 parts of flame retardant; The preparation method is as follows: hydrogenated nitrile rubber and stabilizer are added to a banbury mixer for plasticizing, and plasticizing is carried out at 70℃ for 8 min; the temperature is raised to 100℃, stabilizer, vulcanizing aid, toughening agent, modified glass fiber and flame retardant are added, and mixing is carried out for 13 min to ensure that the inorganic fillers and aids are fully and uniformly dispersed in the rubber matrix, then vulcanizing agent is added, and dynamic vulcanization is carried out for 15 min to obtain the composite material.

[0023] The preparation method of the modified glass fiber comprises: A1, the glass fiber is treated with 5% NaOH solution at 70℃ for 2h, washed to neutral, then treated with 5% dilute hydrochloric acid at room temperature for 30 min, washed and dried to obtain pretreated glass fiber; 100g of the pretreated glass fiber is dispersed in 1000ml of ethanol aqueous solution (the volume ratio of ethanol to water is 4:1), ultrasonic dispersion is carried out, 3.5g of γ-aminopropyl triethoxysilane is added, the temperature is raised to 75℃, and reaction is carried out for 13h; after the reaction is completed, suction filtration is carried out, and washing and drying are carried out to obtain aminated glass fiber; A2, 100g of the aminated glass fiber is dispersed in 1000ml of ethanol, ultrasonic dispersion is carried out, 20g of 5-mercapto-2-pyridine carboxylic acid and 25g of dicyclohexyl carbodiimide are sequentially added, reaction is carried out at 30℃ for 18h under nitrogen protection, after the reaction is completed, suction filtration is carried out, and washing and drying are carried out to obtain mercapto-modified glass fiber; A3. Disperse 100g of mercapto-modified glass fiber in 1000ml of dimethylformamide and sonicate. Add 25g of 1,1,1-trifluoro-2-trifluoromethyl-4-penten-2-ol and 1.5g of 2,2-dimethoxy-2-phenylacetophenone. Irradiate with a 365nm ultraviolet lamp under nitrogen protection and react at 25℃ for 1.5h. After the reaction is completed, filter, wash and dry to obtain modified glass fiber.

[0024] Methods for preparing flame retardants include: B1. Mix 100g vinylphosphonic acid, 80g vinyltrimethoxysilane and 60g 4-vinylpyridine in 1000ml toluene, sonicate for 10min, heat to 65℃ under nitrogen protection, add 2g azobisisobutyronitrile, keep the reaction at this temperature for 7h, and remove the solvent by vacuum distillation after the reaction is complete to obtain the modifier. B2. Disperse 100g of mica powder in 1000ml of anhydrous ethanol, add 12g of modifier, heat to 85℃, keep the temperature for 5h, filter after the reaction, wash and dry to obtain modified mica powder.

[0025] Example 2 This embodiment provides a flame-retardant rubber material for cable seals, comprising the following components by weight: 85 parts hydrogenated nitrile rubber, 3 parts dicumyl peroxide, 2 parts zinc oxide, 6 parts magnesium oxide, 15 parts dioctyl phthalate, 6 parts modified glass fiber, and 20 parts flame retardant. The preparation method is as follows: hydrogenated nitrile rubber and stabilizer are added to a mixer for plasticizing and mixing at 60°C for 10 minutes; the temperature is raised to 90°C, and stabilizer, vulcanizing agent, toughening agent, modified glass fiber and flame retardant are added and mixed for 15 minutes to ensure that inorganic fillers and additives are fully and uniformly dispersed in the rubber matrix. Then, vulcanizing agent is added and dynamic vulcanization is carried out for 20 minutes to obtain the composite material.

[0026] The preparation methods for modified glass fibers include: A1. Glass fibers were treated with 5% NaOH solution at 70℃ for 2 hours, washed to neutral, and then treated with 5% dilute hydrochloric acid at room temperature for 30 minutes. After washing and drying, pretreated glass fibers were obtained. 100g of pretreated glass fibers were dispersed in 1000ml of ethanol aqueous solution (ethanol to water volume ratio of 4:1), ultrasonically dispersed, and 2g of γ-aminopropyltriethoxysilane was added. The temperature was raised to 70℃ and the reaction was carried out for 14 hours. After the reaction was completed, the mixture was filtered, washed, and dried to obtain aminated glass fibers. A2, 100 g of amino glass fiber is dispersed in 1000 ml of ethanol, ultrasonic dispersion, 15 g of 5-mercapto-2-pyridine carboxylic acid and 20 g of dicyclohexyl carbodiimide are added in turn, under nitrogen protection, 25℃ for 24h, after the reaction is completed, suction filtration, washing, drying, to get mercapto glass fiber; A3, 100 g of mercapto glass fiber is dispersed in 1000 ml of dimethylformamide, ultrasonic dispersion, 20 g of 1,1,1-trifluoro-2-trifluoromethyl-4-pentene-2-ol and 1 g of 2,2-dimethoxy-2-phenyl phenylacetone are added, and it is irradiated with a 365 nm ultraviolet lamp under nitrogen protection, and the reaction is carried out at 20℃ for 2h, after the reaction is completed, suction filtration, washing, drying, to get modified glass fiber.

[0027] The preparation method of the flame retardant comprises: B1, 90 g of vinyl phosphonic acid, 70 g of vinyl trimethoxysilane and 50 g of 4-vinyl pyridine are mixed in 1000 ml of toluene, ultrasonic dispersion for 10 min, nitrogen protection, heating to 60℃, adding 1 g of azobisisobutyronitrile, keeping the reaction for 8h, after the reaction is completed, the solvent is removed by distillation under reduced pressure, to get the modifier; B2, 100 g of mica powder is dispersed in 1000 ml of anhydrous ethanol, 10 g of the modifier is added, heated to 80℃, and kept for 6h, after the reaction is completed, suction filtration, washing, drying, to get modified mica powder.

[0028] Example 3 The embodiment provides a flame-retardant rubber material for cable seal, which comprises the following components in parts by weight: 100 parts of hydrogenated nitrile rubber, 5 parts of dicumyl peroxide, 3 parts of zinc oxide, 8 parts of magnesium hydroxide, 25 parts of epoxy soybean oil, 8 parts of modified glass fiber and 25 parts of flame retardant; The preparation method is as follows: the hydrogenated nitrile rubber and the stabilizer are added to a banbury mixer for plasticizing, and the plasticizing is carried out at 80℃ for 5 min; the temperature is raised to 110℃, the stabilizer, the vulcanizing aid, the toughening agent, the modified glass fiber and the flame retardant are added, and the mixing is carried out for 10 min, so that the inorganic filler and the aid are fully and uniformly dispersed in the rubber matrix, then the vulcanizing agent is added, and the dynamic vulcanization is carried out for 10 min, to obtain the composite material.

[0029] The preparation method of the modified glass fiber comprises: A1, the glass fiber is treated with 5% NaOH solution at 70°C for 2h, washed to neutral, then treated with 5% dilute hydrochloric acid at room temperature for 30min, washed and dried to obtain pretreated glass fiber; 100g of the pretreated glass fiber is dispersed in 1000ml of ethanol aqueous solution (volume ratio of ethanol to water is 4:1), ultrasonic dispersion is performed, 5g of γ-aminopropyl triethoxysilane is added, the temperature is raised to 80°C, and reaction is performed for 12h; after the reaction is completed, suction filtration is performed, and washing and drying are performed to obtain aminated glass fiber; A2, 100g of the aminated glass fiber is dispersed in 1000ml of ethanol, ultrasonic dispersion is performed, 25g of 5-mercapto-2-pyridine carboxylic acid and 30g of dicyclohexyl carbodiimide are sequentially added, reaction is performed at 40°C for 12h under nitrogen protection, after the reaction is completed, suction filtration is performed, and washing and drying are performed to obtain mercapto glass fiber; A3, 100g of the mercapto glass fiber is dispersed in 1000ml of dimethylformamide, ultrasonic dispersion is performed, 30g of 1,1,1-trifluoro-2-trifluoromethyl-4-pentene-2-ol and 2g of 2,2-dimethoxy-2-phenyl phenylacetophenone are added, and irradiation is performed with a 365nm ultraviolet lamp under nitrogen protection, reaction is performed at 30°C for 1h, after the reaction is completed, suction filtration is performed, and washing and drying are performed to obtain modified glass fiber.

[0030] The preparation method of the flame retardant includes: B1, 110g of vinyl phosphonic acid, 90g of vinyl trimethoxysilane and 70g of 4-vinyl pyridine are mixed in 1000ml of toluene, ultrasonic dispersion is performed for 10min, 3g of azobisisobutyronitrile is added under nitrogen protection, the temperature is raised to 70°C, and reaction is performed for 6h, after the reaction is completed, the solvent is removed by distillation under reduced pressure to obtain a modifier; B2, 100g of mica powder is dispersed in 1000ml of anhydrous ethanol, 14g of the modifier is added, the temperature is raised to 90°C, and reaction is performed for 4h, after the reaction is completed, suction filtration is performed, and washing and drying are performed to obtain modified mica powder.

[0031] Comparative Example 1 This comparative example provides a flame-retardant rubber material for cable seal, which includes the following components in parts by weight: 93 parts of hydrogenated nitrile rubber, 4 parts of dicumyl peroxide, 2.5 parts of zinc oxide, 7 parts of magnesium oxide, 20 parts of epoxy soybean oil, 7 parts of modified glass fiber and 23 parts of flame retardant, the preparation method is the same as that of Example 1, and the difference lies in that the modified glass fiber is not grafted with 1,1,1-trifluoro-2-trifluoromethyl-4-pentene-2-ol, and the specific process is as follows: The preparation method of the modified glass fiber includes: A1, the glass fiber is treated with 5% NaOH solution at 70°C for 2h, washed to neutral, then treated with 5% dilute hydrochloric acid at room temperature for 30min, washed and dried to obtain pretreated glass fiber; 100g of the pretreated glass fiber is dispersed in 1000ml of ethanol aqueous solution (the volume ratio of ethanol to water is 4:1), ultrasonic dispersion is performed, 3.5g of γ-aminopropyl triethoxysilane is added, the temperature is raised to 75°C, and reaction is performed for 13h; after the reaction is completed, suction filtration is performed, and washing and drying are performed to obtain aminated glass fiber; A2, 100g of the aminated glass fiber is dispersed in 1000ml of ethanol, ultrasonic dispersion is performed, 20g of 5-mercapto-2-pyridine carboxylic acid and 25g of dicyclohexyl carbodiimide are sequentially added, reaction is performed at 30°C for 18h under nitrogen protection, after the reaction is completed, suction filtration is performed, and washing and drying are performed to obtain modified glass fiber.

[0032] Comparative Example 2 This comparative example provides a flame-retardant rubber material for a cable seal, which comprises the following components in parts by weight: hydrogenated nitrile rubber 93 parts, dicumyl peroxide 4 parts, zinc oxide 2.5 parts, magnesium oxide 7 parts, epoxy soybean oil 20 parts, modified glass fiber 7 parts, and flame retardant 23 parts, the preparation method is the same as that of Example 1, and the difference lies in that the modified glass fiber is not grafted with 5-mercapto-2-pyridine carboxylic acid, and the specific process is as follows: The preparation method of the modified glass fiber comprises: A1, the glass fiber is treated with 5% NaOH solution at 70°C for 2h, washed to neutral, then treated with 5% dilute hydrochloric acid at room temperature for 30min, washed and dried to obtain pretreated glass fiber; 100g of the pretreated glass fiber is dispersed in 1000ml of ethanol aqueous solution (the volume ratio of ethanol to water is 4:1), ultrasonic dispersion is performed, 3.5g of γ-aminopropyl triethoxysilane is added, the temperature is raised to 75°C, and reaction is performed for 13h; after the reaction is completed, suction filtration is performed, and washing and drying are performed to obtain aminated glass fiber; A2, 100g of the aminated glass fiber is dispersed in 1000ml of ethanol, ultrasonic dispersion is performed, 20g of 5-mercapto-2-pyridine carboxylic acid and 25g of dicyclohexyl carbodiimide are sequentially added, reaction is performed at 30°C for 18h under nitrogen protection, after the reaction is completed, suction filtration is performed, and washing and drying are performed to obtain modified glass fiber.

[0033] Comparative Example 3 This comparative example provides a flame-retardant rubber material for a cable seal, which comprises the following components in parts by weight: hydrogenated nitrile rubber 93 parts, dicumyl peroxide 4 parts, zinc oxide 2.5 parts, magnesium oxide 7 parts, epoxy soybean oil 20 parts, modified glass fiber 7 parts, and flame retardant 23 parts, the preparation method is the same as that of Example 1, and the difference lies in that: The preparation method of the modified glass fiber comprises: The glass fiber is treated with 5% NaOH solution at 70°C for 2h, washed to neutral, then treated with 5% dilute hydrochloric acid at room temperature for 30min, washed and dried to obtain the pretreated glass fiber; 100g of the pretreated glass fiber is dispersed in 500ml of anhydrous ethanol, ultrasonically dispersed for 30min, then 20g of 5-mercapto-2-pyridine carboxylic acid and 25g of 1,1,1-trifluoro-2-trifluoromethyl-4-pentene-2-ol are added, and mechanical stirring is performed at room temperature for 6h. After the reaction is completed, filtration, washing and drying are performed to obtain the modified glass fiber.

[0034] Comparative Example 4 This comparative example provides a flame-retardant rubber material for a cable seal, which comprises the following components by weight fraction: hydrogenated nitrile rubber 93 parts, dicumyl peroxide 4 parts, zinc oxide 2.5 parts, magnesium oxide 7 parts, epoxy soybean oil 20 parts, modified glass fiber 7 parts and flame retardant 23 parts, the preparation method is the same as that of Example 1, and the difference lies in that: The preparation method of the flame retardant comprises: B1, 100g of vinyl phosphonic acid, 80g of vinyl trimethoxysilane and 60g of 4-vinylpyridine are mixed in 1000ml of toluene, ultrasonically dispersed for 10min, mixed for 7h, and the solvent is removed by vacuum distillation to obtain a modifier; B2, 100g of mica powder is dispersed in 1000ml of anhydrous ethanol, 12g of the modifier is added, heated to 85°C, and reacted for 5h. After the reaction is completed, filtration, washing and drying are performed to obtain modified mica powder.

[0035] Comparative Example 5 This comparative example provides a flame-retardant rubber material for a cable seal, which comprises the following components by weight fraction: hydrogenated nitrile rubber 93 parts, dicumyl peroxide 4 parts, zinc oxide 2.5 parts, magnesium oxide 7 parts, epoxy soybean oil 20 parts, modified glass fiber 7 parts and flame retardant 23 parts, the preparation method is the same as that of Example 1, and the difference lies in that: The preparation method of the flame retardant comprises: B1, 100g of vinyl phosphonic acid, 80g of vinyl trimethoxysilane and 60g of 4-vinylpyridine are mixed in 1000ml of toluene, ultrasonically dispersed for 10min, mixed for 7h, and the solvent is removed by vacuum distillation to obtain a modifier; B2, 100g of mica powder is dispersed in 1000ml of anhydrous ethanol, 12g of the modifier is added, heated to 85°C, and reacted for 5h. After the reaction is completed, filtration, washing and drying are performed to obtain modified mica powder.

[0036] Performance detection The composite materials prepared from the examples and comparative examples are subjected to performance detection, and the detection indexes include tensile strength, water resistance, oil resistance, heat aging resistance, ultraviolet aging resistance and flame retardance. The tensile strength and water resistance of the composite materials are detected according to the national standard GB / T2951-2008, the water resistance is detected by placing the composite materials in water at 100℃ for 164h, and the change rate of the tensile strength is used as the characterization; the oil resistance and heat aging resistance of the composite materials are detected according to the national standard GB / T2941-2006, the oil resistance is detected by placing the composite materials in rubber test oil at 150℃ for 72h, and the change rate of the tensile strength is used as the characterization; the heat aging resistance is detected by placing the composite materials at 170℃ for 72h, and the change rate of the tensile strength is used as the characterization. The ultraviolet aging resistance is detected by placing the composite materials under a 35W ultraviolet lamp for 72h, and the change rate of the tensile strength is used as the characterization; the flame retardance is detected according to the standard GB / T 32129-2015. The detection results are shown in Table 1.

[0037] Table 1 As shown in Table 1, the flame-retardant rubber material prepared by the technical scheme of the present application has good water resistance, oil resistance and aging resistance, and also has excellent flame retardance.

[0038] The above description is only the preferred embodiments of the present application, and is not used to limit the present application, any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A flame retardant rubber material for cable seals, characterized by: By weight parts, including the following components: hydrogenated nitrile rubber 85-100 parts, vulcanizing agent 3-5 parts, vulcanizing aid 2-3 parts, stabilizer 6-8 parts, toughening agent 15-25 parts, modified glass fiber 6-8 parts and flame retardant 20-25 parts.

2. A fire-retardant rubber material for cable seals as claimed in claim 1, characterised in that: The preparation method of the modified glass fiber comprises: A1, the glass fiber is pretreated and dispersed in an ethanol aqueous solution, an amino silane coupling agent is added, the temperature is raised to 70-80 DEG C, and the reaction is carried out for 12-14 h to obtain amino glass fiber; A2, the amino glass fiber is dispersed in a solvent, 5-mercapto-2-pyridine carboxylic acid and dicyclohexyl carbodiimide are added, and the reaction is carried out at 25-40 DEG C for 12-24 h to obtain mercapto glass fiber; A3, the mercapto glass fiber is dispersed in a solvent, 1,1,1-trifluoro-2-trifluoromethyl-4-pentene-2-ol and 2,2-dimethoxy-2-phenyl phenylacetone are added, and the reaction is carried out under ultraviolet lamp at 20-25 DEG C for 1-2 h to obtain modified glass fiber.

3. A fire-retardant rubber material for cable seals as claimed in claim 2, characterised in that: In step A1, the mass ratio of the glass fiber and the amino silane coupling agent is 1:0.02-0.05, and the amino silane coupling agent is one or more of gamma-aminopropyl triethoxysilane and gamma-aminopropyl trimethoxysilane.

4. A fire-retardant rubber material for cable seals as claimed in claim 2, characterised in that: In step A2, the mass ratio of the amino glass fiber, 5-mercapto-2-pyridine carboxylic acid and dicyclohexyl carbodiimide is 10:(1.5-2.5):(2.0-3.0).

5. A fire-retardant rubber material for cable seals as defined in claim 2, characterized in that: In step A3, the mass ratio of the mercapto glass fiber, 1,1,1-trifluoro-2-trifluoromethyl-4-pentene-2-ol and 2,2-dimethoxy-2-phenyl phenylacetone is 10:(2.0-3.0):(0.1-0.2).

6. A fire-retardant rubber material for cable seals as defined in claim 1, characterized in that: The preparation method of the flame retardant comprises: B1, vinyl phosphonic acid, vinyl silane coupling agent and 4-vinyl pyridine are mixed in toluene, azobisisobutyronitrile is added under nitrogen protection, the temperature is raised to 60-70 DEG C, and the reaction is carried out for 6-8 h to obtain a modifier; B2, mica powder is dispersed in anhydrous ethanol, the modifier is added, the temperature is raised to 80-90 DEG C, and the reaction is carried out for 4-6 h to obtain modified mica powder.

7. A fire-retardant rubber material for cable seals as claimed in claim 6, characterised in that: In step B1, the mass ratio of the vinyl phosphonic acid, the vinyl silane coupling agent, the 4-vinyl pyridine and the azobisisobutyronitrile is 9-11:7-9:5-7:0.1-0.3; and the vinyl silane coupling agent is vinyl trimethoxysilane or vinyl triethoxysilane.

8. A fire-retardant rubber material for cable seals as claimed in claim 6, characterised in that: In step B2, the mass ratio of the mica powder and the modifier is 100:10-14.

9. A fire-retardant rubber material for cable seals as defined in claim 1, characterized in that: The toughening agent is epoxy soybean oil, dioctyl phthalate or dioctyl adipate; the vulcanizing agent is one or more of di-t-butyl peroxide, dicumyl peroxide or 2,5-dimethyl-2,5-di(t-butyl peroxide) hexane, the vulcanizing aid is zinc oxide; and the stabilizer is magnesium oxide or magnesium hydroxide.

10. A process for the preparation of a flame retardant rubber material for cable seals according to any one of claims 1 to 9, characterized in that: The preparation method of the flame-retardant rubber material comprises the following steps: Hydrogenated butyl rubber and stabilizer are added into the internal mixer for plasticizing, and are mixed for 5-10 minutes at 60-80 ℃; the temperature is raised to 90-110 ℃, stabilizer, vulcanization accelerator, toughener, modified glass fiber and flame retardant are added, and are mixed for 10-15 minutes to ensure that the inorganic fillers and additives are fully and uniformly dispersed in the rubber matrix, then vulcanizing agent is added, and dynamic vulcanization is carried out for 10-20 minutes to obtain the composite material.

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