Organic silicon master batch applied to special cable and preparation method of organic silicon master batch

Abstract

The invention relates to the technical field of silicone rubber materials, in particular to an organic silicon master batch applied to a special cable and a preparation method of the organic silicon master batch. The organic silicon master batch applied to the special cable is prepared from methyl vinyl silicone rubber, fumed silica, modified tungsten boride, hydroxyl silicone oil and a vulcanizing agent, and the modified tungsten boride is prepared through a three-step process: firstly, performing alkenylation treatment on tungsten boride, and then forming a core-shell structure through aniline polymerization; and finally, carrying out ion exchange modification by using sodium p-vinylbenzene sulfonate. The organic silicon master batch applied to the special cable has high mechanical strength and excellent radiation resistance, and is particularly suitable for manufacturing the special cable in extreme environments such as a nuclear power station and the like.

Description

Technical Field

[0001] This invention relates to the field of silicone rubber materials technology, and in particular to an organosilicon masterbatch for use in special cables and its preparation method. Background Technology

[0002] Nuclear power, as a highly efficient and environmentally friendly new energy source, has become one of my country's major strategies for adjusting its energy structure in recent years. With the continuous increase in nuclear power plant construction projects, public concern about nuclear power safety is also growing. Radiation accelerates the aging of materials used in nuclear power plants, reduces the normal service life of nuclear power facilities and equipment, and poses safety hazards. Traditional ethylene propylene rubber cable materials will experience a series of problems under such conditions, including insulation carbonization, filler decomposition due to radiation, and seal failure.

[0003] Patent document CN117700891A discloses a radiation-resistant and tensile-resistant cable. Its protective sheath is made of EPDM rubber, chlorinated polyethylene, carbon black, silica, additives, antioxidants, paraffin wax, zinc oxide, crosslinking sensitizer, and sulfur. The resulting cable has stable and efficient radiation resistance, aging resistance, abrasion resistance, tensile and tear resistance, and a certain degree of flame retardancy. However, the poor compatibility between excessive conventional inorganic fillers and the organosilicon matrix, and the physical blending easily leads to phase separation, resulting in weak interfacial bonding. Under dynamic bending or thermal cycling conditions, microcracks are easily generated at the filler-matrix interface, becoming the starting point for electrical breakdown and mechanical failure. Moreover, the cable is in a high-pressure, high-radiation environment in nuclear power plants for a long time, which affects the service life of the cable. Summary of the Invention

[0004] In view of this, the purpose of this invention is to provide an organosilicon masterbatch for use in special cables and its preparation method, so as to provide an organosilicon masterbatch for special cables that has both high mechanical strength and excellent radiation resistance.

[0005] To achieve the above objectives, the present invention provides an organosilicon masterbatch for use in special cables, which is prepared from the following raw materials in parts by weight: 100-110 parts methyl vinyl silicone rubber, 10-12 parts reinforcing filler, 25-30 parts modified tungsten boride, 8-10 parts hydroxyl silicone oil, and 2-3 parts vulcanizing agent.

[0006] The preparation steps of the modified tungsten boride are as follows:

[0007] S1: Take tungsten boride powder and vinyltrimethoxysilane, place them in a mixed solution of anhydrous ethanol and deionized water, and carry out a hydrolysis-condensation reaction to obtain alkenylated tungsten boride.

[0008] S2: Disperse alkenyl boron tungsten in hydrochloric acid solution, add sodium dodecylbenzene sulfonate, stir evenly, then add aniline and potassium persulfate solution dropwise, and polymerize at 65-75℃. After the reaction is completed, centrifuge, filter, purify, and dry to obtain tungsten boron with a core-shell structure.

[0009] S3: Tungsten boride with a core-shell structure is immersed in a sodium p-vinylbenzenesulfonate solution and subjected to ion exchange at 60-65℃. The resulting product is centrifuged, filtered, purified, and dried to obtain modified tungsten boride.

[0010] Preferably, the methyl vinyl silicone rubber has an average molecular weight of 600,000-700,000 and a vinyl molar content of 0.15%-0.3%.

[0011] Preferably, the reinforcing filler is fumed silica with a specific surface area of ​​190-210 m². 2 / g, with an average particle size of 10-40nm.

[0012] Preferably, the viscosity of the hydroxyl silicone oil is 30-35 mm. 2 / s (25℃), hydroxyl content is 8%-10%.

[0013] Preferably, the vulcanizing agent is 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane.

[0014] Preferably, the ratio of tungsten boride powder, vinyltrimethoxysilane, anhydrous ethanol and deionized water in step S1 is 40-50g:12-15mL:450-475mL:25-50mL.

[0015] Preferably, the tungsten boride powder in step S1 has a size of 1-3 μm and a purity of ≥99%.

[0016] Preferably, the hydrolysis-condensation reaction in step S1 is carried out under a nitrogen atmosphere at a reaction temperature of 50-60°C.

[0017] Preferably, the ratio of the amount of alkenyl boron tungsten, hydrochloric acid solution, sodium dodecylbenzenesulfonate, aniline, and potassium persulfate solution used in step S2 is 40-50g:450-500mL:0.4-0.5g:16-20mL:1.6-2mL.

[0018] Preferably, the pH of the hydrochloric acid solution in step S2 is 1.0.

[0019] Preferably, the dropping rate of both aniline and potassium persulfate solution in step S2 is 2 mL / min.

[0020] Preferably, the concentration of the potassium persulfate solution in step S2 is 0.1 mol / L.

[0021] Preferably, the purification in step S2 involves washing three times each with deionized water, acetone, and tetrahydrofuran.

[0022] Preferably, the ratio of the core-shell structured tungsten boride to sodium p-vinylbenzenesulfonate solution in step S3 is 40-50g:200-300mL.

[0023] Preferably, the concentration of the sodium p-vinylbenzenesulfonate solution in step S3 is 0.2 mol / L.

[0024] Furthermore, the present invention also provides a method for preparing organosilicon masterbatch for use in special cables, the specific steps of which are as follows:

[0025] Methyl vinyl silicone rubber is added to a mixing mill and preheated to 83-87℃. After the rubber softens, the rotor is turned on. Then, fumed silica and modified tungsten boride are added to the mixing mill and mixed at 93-97℃ for 30-60 minutes. Then, the temperature is raised to 108-112℃, hydroxyl silicone oil and 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane are added. After premixing at 150℃, the mixture is transferred to a co-rotating twin-screw extruder and melt-extruded at 200-210℃. After water cooling, the silicone masterbatch for use in special cables is obtained.

[0026] The beneficial effects of this invention are:

[0027] This invention constructs an organosilicon masterbatch system with a multi-level interface structure through a three-step modification process (alkenylation-polyaniline coating-sulfonic acid group modification). First, sodium p-vinylbenzenesulfonate is used to achieve a "one-molecule dual-function" design. The vinyl group participates in the vulcanization crosslinking network, and the sulfonic acid group forms a dynamic bond, upgrading the filler-matrix interface bonding energy from physical adsorption to chemical bonding. At the same time, its phenyl group can improve the material's aging resistance and radiation resistance. Second, the coating structure constructed by aniline on the surface of tungsten boride has a unique conjugated structure that can effectively disperse mechanical stress. This polar group forms dynamic crosslinking points with the silicone rubber molecular chain, enhancing the interfacial bonding strength. The π-π conjugation effect disperses stress and dissipates radiation energy, providing a solution for special cables used in extreme environments such as nuclear power plants that combines high mechanical strength and excellent radiation resistance. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0029] The sources or properties of the raw materials used in the embodiments and comparative examples of this invention are as follows:

[0030] Methyl vinyl silicone rubber: average molecular weight 600,000-700,000, vinyl molar content 0.15%-0.3%; Fumed silica: specific surface area 190-210 m² / g. 2 / g, with an average particle size of 10-40nm; Hydroxy silicone oil: viscosity 30-35mm 2 / s (25℃), hydroxyl content is 8%-10%; tungsten boride powder: 1-3um, purity ≥99%, purchased from Zhongke Jinyan, model DK-WB-500.

[0031] Example 1: An organosilicon masterbatch for use in special cables, the specific preparation steps are as follows:

[0032] (1) Under a nitrogen atmosphere, 40g of tungsten boride powder, 12mL of vinyltrimethoxysilane, 450mL of anhydrous ethanol and 50mL of deionized water were added to the reaction vessel and reacted at 50℃ for 3h. After the reaction was completed, the mixture was centrifuged, washed and dried under vacuum to obtain alkenylated tungsten boride.

[0033] (2) 40g of alkenyl boron tungsten was dispersed in 450mL of hydrochloric acid solution with pH 1.0, and 0.4g of sodium dodecylbenzenesulfonate was added. After stirring and dispersing evenly, 16mL of aniline and 1.6mL of potassium persulfate solution (0.1mol / L) were added dropwise to the reaction system (dropping rate 2mL / min). The polymerization was carried out at 65℃ for 7h. After the reaction was completed, the mixture was centrifuged and filtered. It was washed three times each with deionized water, acetone and tetrahydrofuran, and dried to obtain tungsten boron with a core-shell structure.

[0034] (3) Immerse 40g of tungsten boride with a core-shell structure in 200mL of 0.2mol / L sodium p-vinylbenzenesulfonate solution and keep it at 60℃ for 2h. Centrifuge, filter and dry the product to obtain modified tungsten boride.

[0035] (4) 100g of methyl vinyl silicone rubber was put into a mixer and heated to 83°C for 15 minutes. After the rubber softened, the rotor was turned on (55 rpm). Then, 10g of fumed silica and 25g of modified tungsten boride were added to the mixer at a feeding rate of 3.5g / min. The mixture was mixed at 93°C for 30 minutes. Then, the temperature was raised to 108°C, and 8g of hydroxyl silicone oil and 2g of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane were added. After premixing at 150°C, the mixture was transferred to a co-rotating twin-screw extruder and melt-extruded at 200°C. After water cooling, the silicone masterbatch for use in special cables was obtained.

[0036] Example 2: An organosilicon masterbatch for use in special cables, the specific preparation steps are as follows:

[0037] (1) Under a nitrogen atmosphere, 45g of tungsten boride powder, 13.5mL of vinyltrimethoxysilane, 475mL of anhydrous ethanol and 25mL of deionized water were added to the reaction vessel and reacted at 55℃ for 4h. After the reaction was completed, the mixture was centrifuged, washed and dried under vacuum to obtain alkenylated tungsten boride.

[0038] (2) 45g of alkenyl boron tungsten was dispersed in 480mL of hydrochloric acid solution with pH 1.0, and 0.45g of sodium dodecylbenzenesulfonate was added. After stirring and dispersing evenly, 18mL of aniline and 1.8mL of potassium persulfate solution (0.1mol / L) were added dropwise to the reaction system (dropping rate 2mL / min). Polymerization was carried out at 70℃ for 8h. After the reaction was completed, the mixture was centrifuged and filtered, and washed three times each with deionized water, acetone and tetrahydrofuran. After drying, tungsten boron with a core-shell structure was obtained.

[0039] (3) Immerse 45g of tungsten boride with a core-shell structure in 250mL of 0.2mol / L sodium p-vinylbenzenesulfonate solution and keep it at 63℃ for 3h. Centrifuge, filter and dry the product to obtain modified tungsten boride.

[0040] (4) 105g of methyl vinyl silicone rubber was put into a mixer and preheated to 85°C for 20 minutes. After the rubber softened, the rotor was turned on (60 rpm). Then, 11g of fumed silica and 28g of modified tungsten boride were added to the mixer at a feeding rate of 4g / min. The mixture was mixed at 95°C for 50 minutes. Then, the temperature was raised to 110°C, and 9g of hydroxyl silicone oil and 2.5g of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane were added. After premixing at 150°C, the mixture was transferred to a co-rotating twin-screw extruder and melt-extruded at 210°C. The mixture was then water-cooled to obtain the silicone masterbatch for use in special cables.

[0041] Example 3: An organosilicon masterbatch for use in special cables, the specific preparation steps are as follows:

[0042] (1) Under a nitrogen atmosphere, 50g of tungsten boride powder, 15mL of vinyltrimethoxysilane, 475mL of anhydrous ethanol and 25mL of deionized water were added to the reaction vessel and reacted at 60℃ for 4h. After the reaction was completed, the mixture was centrifuged, washed and dried under vacuum to obtain alkenylated tungsten boride.

[0043] (2) Disperse 50g of alkenyl boron tungsten in 500mL of hydrochloric acid solution with pH 1.0, add 0.5g of sodium dodecylbenzenesulfonate, stir and disperse evenly, then add 20mL of aniline and 2mL of potassium persulfate solution (0.1mol / L) dropwise (dropping rate 2mL / min) to the reaction system, polymerize at 75℃ for 9h, centrifuge and filter after the reaction is completed, wash with deionized water, acetone and tetrahydrofuran three times each, dry to obtain tungsten boron with core-shell structure;

[0044] (3) Immerse 50g of tungsten boride with a core-shell structure in 300mL of 0.2mol / L sodium p-vinylbenzenesulfonate solution and keep it at 65℃ for 3h. Centrifuge, filter and dry the product to obtain modified tungsten boride.

[0045] (4) 110g of methyl vinyl silicone rubber was put into a mixer and heated to 87°C for 30 minutes. After the rubber softened, the rotor was turned on (65 rpm). Then, 12g of fumed silica and 30g of modified tungsten boride were added to the mixer at a feeding rate of 4.5g / min. The mixture was mixed at 97°C for 60 minutes. Then, the temperature was raised to 112°C, and 10g of hydroxyl silicone oil and 3g of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane were added. After premixing at 150°C, the mixture was transferred to a co-rotating twin-screw extruder and melt-extruded at 220°C. After water cooling, the silicone masterbatch for use in special cables was obtained.

[0046] Comparative Example 1: The difference from Example 2 is that tungsten boride is directly added to the rubber. The specific steps are as follows:

[0047] (1) 105g of methyl vinyl silicone rubber was put into a mixer and preheated to 85°C for 20min. After the rubber softened, the rotor was turned on (60rpm). Then, 11g of fumed silica and 28g of tungsten boride were added to the mixer at a feeding rate of 4g / min. The mixture was mixed at 95°C for 50min. Then, the temperature was raised to 110°C, and 9g of hydroxyl silicone oil and 2.5g of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane were added. After premixing at 150°C, the mixture was transferred to a co-rotating twin-screw extruder and melt-extruded at 210°C. The mixture was then water-cooled to obtain silicone masterbatch for use in special cables.

[0048] Comparative Example 2: The difference from Example 2 is that only tungsten boride is modified with an alkenylation method. The specific steps are as follows:

[0049] (1) Under a nitrogen atmosphere, 45g of tungsten boride powder, 13.5mL of vinyltrimethoxysilane, 475mL of anhydrous ethanol and 25mL of deionized water were added to the reaction vessel and reacted at 55℃ for 4h. After the reaction was completed, the mixture was centrifuged, washed and dried under vacuum to obtain alkenylated tungsten boride.

[0050] (2) 105g of methyl vinyl silicone rubber was put into a mixer and preheated to 85°C for 20 minutes. After the rubber softened, the rotor was turned on (60 rpm). Then, 11g of fumed silica and 28g of alkenyl boron tungsten were added to the mixer at a feeding rate of 4g / min. The mixture was mixed at 95°C for 50 minutes. Then, the temperature was raised to 110°C, and 9g of hydroxyl silicone oil and 2.5g of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane were added. After premixing at 150°C, the mixture was transferred to a co-rotating twin-screw extruder and melt-extruded at 210°C. The mixture was then water-cooled to obtain silicone masterbatch for use in special cables.

[0051] Comparative Example 3: The difference from Example 2 is that ion exchange is not performed. The specific steps are as follows:

[0052] (1) Under a nitrogen atmosphere, 45g of tungsten boride powder, 13.5mL of vinyltrimethoxysilane, 475mL of anhydrous ethanol and 25mL of deionized water were added to the reaction vessel and reacted at 55℃ for 4h. After the reaction was completed, the mixture was centrifuged, washed and dried under vacuum to obtain alkenylated tungsten boride.

[0053] (2) 45g of alkenyl boron tungsten was dispersed in 480mL of hydrochloric acid solution with pH 1.0, and 0.45g of sodium dodecylbenzenesulfonate was added. After stirring and dispersing evenly, 18mL of aniline and 1.8mL of potassium persulfate solution (0.1mol / L) were added dropwise to the reaction system (dropping rate 2mL / min). Polymerization was carried out at 70℃ for 8h. After the reaction was completed, the mixture was centrifuged and filtered, and washed three times each with deionized water, acetone and tetrahydrofuran. After drying, tungsten boron with a core-shell structure was obtained.

[0054] (3) 105g of methyl vinyl silicone rubber was put into a mixer and heated to 85°C for 20 minutes. After the rubber softened, the rotor was turned on (60 rpm). Then, 11g of fumed silica and 28g of tungsten boride with a core-shell structure were fed into the mixer at a feeding rate of 4g / min. The mixture was mixed at 95°C for 50 minutes. Then, the temperature was raised to 110°C, and 9g of hydroxyl silicone oil and 2.5g of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane were added. After premixing at 150°C, the mixture was transferred to a co-rotating twin-screw extruder and melt-extruded at 210°C. After water cooling, the silicone masterbatch for use in special cables was obtained.

[0055] (4) The mixture is transferred to a co-rotating twin-screw extruder, melt-extruded, and water-cooled to obtain an organosilicon masterbatch for use in special cables. The twin-screw extruder has a screw speed of 180 rpm, a die head temperature of 155°C, a zone 1 temperature of 120°C, a zone 2 temperature of 135°C, a zone 3 temperature of 145°C, and a zone 4 temperature of 140°C.

[0056] Comparative Example 4: The difference from Example 2 is that the sodium p-vinylbenzenesulfonate solution was replaced with a sodium benzenesulfonate solution;

[0057] (1) Under a nitrogen atmosphere, 45g of tungsten boride powder, 13.5mL of vinyltrimethoxysilane, 475mL of anhydrous ethanol and 25mL of deionized water were added to the reaction vessel and reacted at 55℃ for 4h. After the reaction was completed, the mixture was centrifuged, washed and dried under vacuum to obtain alkenylated tungsten boride.

[0058] (2) 45g of alkenyl boron tungsten was dispersed in 480mL of hydrochloric acid solution with pH 1.0, and 0.45g of sodium dodecylbenzenesulfonate was added. After stirring and dispersing evenly, 18mL of aniline and 1.8mL of potassium persulfate solution (0.1mol / L) were added dropwise to the reaction system (dropping rate 2mL / min). Polymerization was carried out at 70℃ for 8h. After the reaction was completed, the mixture was centrifuged and filtered, and washed three times each with deionized water, acetone and tetrahydrofuran. After drying, tungsten boron with a core-shell structure was obtained.

[0059] (3) Immerse 45g of tungsten boride with a core-shell structure in 250mL of 0.2mol / L sodium benzenesulfonate solution and keep it at 63℃ for 3h. Centrifuge, filter and dry the product to obtain modified tungsten boride.

[0060] (4) 105g of methyl vinyl silicone rubber was put into a mixer and preheated to 85°C for 20 minutes. After the rubber softened, the rotor was turned on (60 rpm). Then, 11g of fumed silica and 28g of modified tungsten boride were added to the mixer at a feeding rate of 4g / min. The mixture was mixed at 95°C for 50 minutes. Then, the temperature was raised to 110°C, and 9g of hydroxyl silicone oil and 2.5g of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane were added. After premixing at 150°C, the mixture was transferred to a co-rotating twin-screw extruder and melt-extruded at 210°C. The mixture was then water-cooled to obtain the silicone masterbatch for use in special cables.

[0061] Performance testing

[0062] Hardness: Tested using a Shore hardness tester;

[0063] Tensile strength: Tested according to GB / T 528-2009, tensile rate 500 mm / min;

[0064] Radiation resistance performance: The tensile strength of the test samples after being irradiated with 60Co-γ rays (cumulative radiation measurement of 250kGy, dose rate should not be greater than 10kGy / h) was determined according to IEC60811-4-2-2004.

[0065] Thermal aging performance: The experiment was conducted according to GB / T 3512-2014. The sample was treated in a 200℃ hot air aging chamber for 168h. After cooling to room temperature, the change rate of tensile strength was tested. The test results are shown in Table 1.

[0066] Table 1 Performance Test Results

[0067]

[0068] Data Analysis: As can be seen from the data of Examples 1-3 in Table 1, the organosilicon masterbatch prepared by this invention exhibits excellent comprehensive performance. Through a three-step modification process of tungsten boride surface alkenylation grafting, polyaniline coating, and sulfonic acid group modification, a multi-level interfacial interaction network is constructed between the filler and the silicone rubber matrix. The polyaniline shell disperses mechanical stress through the π-π conjugation effect, and its benzene ring structure can effectively capture free radicals generated by radiation. This is the key to maintaining high tensile strength and excellent radiation retention rate. At the same time, the introduction of sodium vinylbenzenesulfonate not only enhances the interfacial bonding force between the filler and the matrix through ionic bonds, but its sulfonic acid groups can also form a hydrogen bond network with the polar groups in the silicone rubber, significantly improving thermal stability. Furthermore, its alkenyl groups enable the modified tungsten boride to participate in subsequent vulcanization crosslinking.

[0069] Comparative analysis of the data from Example 2 and Comparative Examples 3 and 4 in Table 1 shows that the present invention, through the process of ion-exchange modification of sodium vinylbenzenesulfonate, significantly improves the performance of the organosilicon masterbatch. Firstly, the vinyl groups in the sodium vinylbenzenesulfonate molecule can covalently crosslink with the vinyl groups in methyl vinyl silicone rubber, forming a tighter filler-matrix interface bond during subsequent vulcanization. Secondly, the sulfonic acid groups form stable chemical bonds with the surface of tungsten boride. This bonding enhances the interfacial bonding strength between the filler and the matrix, and the synergistic effect of the benzene ring structure and sulfonic acid groups may enhance the thermal stability of the material through intermolecular forces. Particularly noteworthy is that, compared to ordinary sodium benzenesulfonate and samples without ion exchange, the bifunctional nature of sodium vinylbenzenesulfonate allows it to participate in the crosslinking network through vinyl groups and improve interfacial compatibility through sulfonic acid groups. This dual-action mechanism provides a reliable guarantee for the long-term stable operation of special cable materials under high voltage and radiation environments.

[0070] The performance data comparison analysis of Example 2 and Comparative Examples 1 and 2 in Table 1 shows that the present invention, through a multi-step modification process combining polyaniline coating with sodium vinylbenzenesulfonate modification, significantly improves the overall performance of the organosilicon masterbatch. Firstly, the polyaniline shell forms a coating on the tungsten boride surface, and its unique conjugated structure effectively disperses mechanical stress and dissipates radiation energy through electron delocalization. Secondly, the modification of sodium vinylbenzenesulfonate introduces sulfonic acid groups onto the filler surface. These polar groups form dynamic crosslinking points with the silicone rubber molecular chains, enhancing the interfacial bonding strength. Furthermore, the synergistic effect of the benzene ring structure of polyaniline and the sulfonic acid groups may construct a more stable filler-matrix interface structure through π-π stacking and hydrogen bonding interactions. Particularly noteworthy is that, compared to samples that only undergo alkenylation modification and those that directly add tungsten boride, this core-shell structure design significantly improves the dispersibility of the filler in the matrix, avoiding the agglomeration phenomenon that easily occurs in uncoated fillers, while effectively inhibiting molecular chain degradation during radiation and thermal aging.

[0071] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention is limited to these examples; within the framework of the invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in detail for the sake of brevity.

Claims

1. A silicone masterbatch for use in special cables, characterized in that, It is prepared from the following raw materials in parts by weight: 100-110 parts methyl vinyl silicone rubber, 10-12 parts reinforcing filler, 25-30 parts modified tungsten boride, 8-10 parts hydroxyl silicone oil, and 2-3 parts vulcanizing agent; The preparation steps of the modified tungsten boride are as follows: S1: Take tungsten boride powder and vinyltrimethoxysilane, place them in a mixed solution of anhydrous ethanol and deionized water, and carry out a hydrolysis-condensation reaction to obtain alkenylated tungsten boride. S2: Disperse alkenyl boron tungsten in hydrochloric acid solution, add sodium dodecylbenzene sulfonate, stir evenly, then add aniline and potassium persulfate solution dropwise, and polymerize at 65-75℃. After the reaction is completed, centrifuge, filter, purify, and dry to obtain tungsten boron with a core-shell structure. S3: Tungsten boride with a core-shell structure is immersed in a sodium p-vinylbenzenesulfonate solution and subjected to ion exchange at 60-65℃. The resulting product is centrifuged, filtered, purified, and dried to obtain modified tungsten boride.

2. The organosilicon masterbatch for use in special cables according to claim 1, characterized in that, The ratio of tungsten boride powder, vinyltrimethoxysilane, anhydrous ethanol and deionized water in step S1 is 40-50g:12-15mL:450-475mL:25-50mL.

3. The organosilicon masterbatch for use in special cables according to claim 1, characterized in that, In step S2, the ratio of alkenyl boron tungsten, hydrochloric acid solution, sodium dodecylbenzenesulfonate, aniline, and potassium persulfate solution is 40-50g:450-500mL:0.4-0.5g:16-20mL:1.6-2mL.

4. The organosilicon masterbatch for use in special cables according to claim 1, characterized in that, The tungsten boride powder mentioned in step S1 has a size of 1-3 μm and a purity of ≥99%.

5. The organosilicon masterbatch for use in special cables according to claim 1, characterized in that, In step S3, the ratio of tungsten boride with a core-shell structure to sodium p-vinylbenzenesulfonate solution is 40-50g: 200-300mL.

6. The organosilicon masterbatch for use in special cables according to claim 1, characterized in that, The methyl vinyl silicone rubber has an average molecular weight of 600,000-700,000 and a vinyl molar content of 0.15%-0.3%.

7. The organosilicon masterbatch for use in special cables according to claim 1, characterized in that, The reinforcing filler is fumed silica produced by fumed silica production, with a specific surface area of ​​190-210 m². 2 / g, with an average particle size of 10-40nm.

8. The organosilicon masterbatch for use in special cables according to claim 1, characterized in that, The viscosity of the hydroxyl silicone oil is 30-35 mm. 2 / s, with a hydroxyl content of 8%-10%.

9. The organosilicon masterbatch for use in special cables according to claim 1, characterized in that, The vulcanizing agent is 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane.

10. A method for preparing an organosilicon masterbatch for use in special cables according to claims 1-9, characterized in that, The specific steps are as follows: Methyl vinyl silicone rubber is fed into a mixing mill and preheated. After the rubber softens, the rotor is turned on. Then, fumed silica and modified tungsten boride are fed into the mixing mill and mixed at 93-97°C. The temperature is then raised to 108-112°C, and hydroxyl silicone oil and 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane are added. After premixing at 150°C, the mixture is transferred to a co-rotating twin-screw extruder and melt-extruded at 200-210°C. After water cooling, the silicone masterbatch for use in special cables is obtained.

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