Corrosion-resistant silicone rubber composition and preparation method thereof

Abstract

The invention discloses a corrosion-resistant silicone rubber composition and a preparation method thereof.The silicone rubber is prepared from, by weight, 80-100 parts of polysiloxane, 5-10 parts of a modified additive and 0.03-0.05 part of a Karst catalyst, when the raw materials are injected into a mold to be subjected to high-temperature reaction, Si-H bonds on a polysiloxane molecular chain are grafted with double bonds on the modified additive, and when the raw materials are injected into the mold to be subjected to high-temperature reaction, the Si-H bonds on the modified additive are grafted with the double bonds on the modified additive; the cross-linked network can reduce molecular chain segment movement, reduce diffusion paths of corrosive media and effectively prevent permeation of corrosion factors such as moisture, oxygen and ions, methyl, phenyl and fluoroalkyl of side chains further shield a main chain through a hydrophobic effect, permeation and attack of chemical media are reduced, and the corrosion resistance is improved. The inorganic filler part can form a physical barrier in the material, so that the corrosion resistance effect of the prepared silicone rubber composition is further improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of silicone rubber preparation, and particularly relates to a corrosion-resistant silicone rubber composition and a preparation method thereof. BACKGROUND

[0002] As an important polymer material, the main chain of silicone rubber is composed of silicon atoms and oxygen atoms arranged alternately (-Si-O-Si-), and the side groups are usually organic groups such as methyl, vinyl and phenyl. The unique semi-inorganic and semi-organic structure endows silicone rubber with many excellent properties, such as excellent high and low temperature resistance (-60 DEG C to 250 DEG C), good weather resistance and electrical insulation, and inherent physiological inertia. Although the Si-O bond in the molecular chain of ordinary silicone rubber is stable, it can be easily broken under acidic or alkaline conditions. In particular, under high temperature environment, acid and alkali can catalyze the hydrolysis of the silicon-oxygen main chain, resulting in degradation of the polymer. For example, in a high-temperature acidic environment, the molecular chain of silicone rubber can be degraded in a buckle manner, resulting in a sharp decrease in the mechanical properties of the material. In addition, the active groups such as residual hydroxyl groups in the silicone rubber can also accelerate the degradation reaction of the main chain at high temperature, significantly affecting the service life of the material, and affecting the use of the silicone rubber. SUMMARY

[0003] The present application relates to the technical field of silicone rubber preparation, and particularly relates to a corrosion-resistant silicone rubber composition and a preparation method thereof.

[0004] The object of the present application can be achieved by the following technical solutions.

[0005] A preparation method of a corrosion-resistant silicone rubber composition, specifically comprising the following steps:

[0006] Step A1: mixing dimethyl vinylsilanol lithium and tetrahydrofuran, and protecting by introducing nitrogen, stirring under the condition of a rotation speed of 200-300 r / min and a temperature of 0 DEG C, adding trifluoropropylmethylcyclotrisiloxane, heating to 25-30 DEG C, and reacting for 8-10 h, then adding a modified filler and continuing to react for 3-5 h to obtain a modified additive;

[0007] Step A2: mixing diphenyldimethoxysilane, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, hexamethyldisiloxane, tetramethylammonium hydroxide and deionized water, protecting by introducing nitrogen, reacting under the condition of a rotation speed of 200-300 r / min and a temperature of 90-95 DEG C for 10-15 h, heating to 105-110 DEG C, and reacting for 2-3 h, heating to 150-160 DEG C, and keeping for 30-40 min to obtain polysiloxane;

[0008] Step A3: take the following weight parts of raw materials: polysiloxane 80-100 parts, modified additive 5-10 parts and Kastle catalyst 0.03-0.05 parts, mix the raw materials uniformly and inject into the mold, under the condition of temperature 30-40℃, react for 20-30min, then heat to 160-170℃, continue to react for 40-50min, to obtain the corrosion-resistant silicone rubber composition.

[0009] Further, the molar ratio of dimethyl vinyl silanol lithium, trifluoropropyl methyl cyclotrisiloxane and Si-Cl bond on the modified filler in step A1 is 1:4:1.

[0010] Further, the use amount ratio of diphenyl dimethoxysilane, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, hexamethyldisiloxane, tetramethylammonium hydroxide and deionized water in step A2 is 0.2mol:2mol:0.2mol:1mol:2mol:40mL.

[0011] Further, the modified filler is prepared by the following steps:

[0012] Step B1: mix carbon nanotubes, concentrated sulfuric acid and concentrated nitric acid, under the condition of rotation speed 300-500r / min and temperature 100-110℃, react for 3-5h, filter to remove the filtrate and dry to obtain carboxylated carbon nanotubes, mix sulfurous chloride and N,N-dimethylformamide uniformly, under the condition of rotation speed 200-300r / min and temperature 90-95℃, stir and add carboxylated carbon nanotubes, react for 4-6h to obtain functionalized carbon nanotubes;

[0013] Step B2: mix boron nitride and urea and add to a ball mill, under the condition of rotation speed 500r / min and nitrogen atmosphere, ball mill for 20-24h, mix with deionized water, filter to remove the filtrate and dry to obtain aminated boron nitride, mix functionalized carbon nanotubes, aminated boron nitride, triethylamine and N,N-dimethylformamide, under the condition of rotation speed 600-800r / min and temperature 20-25℃, react for 6-8h to obtain a composite filler;

[0014] Step B3: mix the composite filler, acrylic acid, dicyclohexyl carbodiimide and N,N-dimethylformamide, under the condition of rotation speed 150-200r / min and temperature 40-50℃, react for 4-6h to obtain a pretreated filler, mix the pretreated filler, methyl dichlorosilane, Kastle catalyst and N,N-dimethylformamide, protect with nitrogen, under the condition of rotation speed 120-150r / min and temperature 80-85℃, react for 6-8h to obtain a modified filler.

[0015] Further, the use amount ratio of the carbon nanotube, concentrated sulfuric acid and concentrated nitric acid in step B1 is 50 mg:3 mL:1 mL, the mass fraction of the concentrated sulfuric acid is 98%, the mass fraction of the concentrated nitric acid is 68%, and the use amount ratio of the thionyl chloride, N,N-dimethylformamide and carboxylated carbon nanotube is 75 mL:1 mL:500 mg.

[0016] Further, the mass ratio of the boron nitride and urea in step B2 is 1:30, and the use amount ratio of the functionalized carbon nanotube, aminated boron nitride, triethylamine and N,N-dimethylformamide is 100 mg:500 mg:0.3 mL:40 mL.

[0017] Further, the molar ratio of the amino group, acrylic acid and dicyclohexyl carbodiimide on the composite filler in step B3 is 1:1:1, the molar ratio of the double bond on the pretreated filler and methyldichlorosilane is 1:1, and the use amount of the Karstedt catalyst is 0.01% of the mass of the methyldichlorosilane.

[0018] The present application has the following beneficial effects: The corrosion-resistant silicone rubber composition disclosed in the present application comprises the following raw materials: polysiloxane, modified additive and Karstedt catalyst, the polysiloxane is prepared by hydrolysis of diphenyldimethoxysilane as a raw material, ring-opening condensation of octamethylcyclotetrasiloxane and tetramethylcyclotetrasiloxane, and end-capping with hexamethyldisiloxane.

[0019] The modified additive is prepared by using dimethylvinylsilanol lithium as an initiator, trifluoropropylmethyltrisiloxane as a polymerization monomer to form polysiloxane with one end of a vinyl group and the other end of a silanol lithium, and then adding a modified filler to make the Si-Cl on the surface react with the silanol lithium. The modified filler is prepared by using carbon nanotubes as a raw material, treating with concentrated sulfuric acid and concentrated nitric acid to obtain carboxylated carbon nanotubes, treating the carboxylated carbon nanotubes with thionyl chloride to convert the carboxyl groups into acyl chloride to obtain functionalized carbon nanotubes, reacting the functionalized carbon nanotubes with aminated boron nitride to make the acyl chloride on the functionalized carbon nanotubes react with part of the amino groups on the aminated boron nitride to obtain a composite filler, reacting the composite filler with acrylic acid to make the remaining amino groups on the composite filler dehydrate with the acrylic acid to obtain a pretreated filler, and reacting the pretreated filler with methyldichlorosilane to make the double bond on the pretreated filler react with the Si-H bond on the methyldichlorosilane to obtain a modified filler.

[0020] In the high-temperature reaction of the raw material injected into the mold, the Si-H bond on the polysiloxane molecular chain will graft with the double bond on the modified additive, and then a crosslinked network is formed. The crosslinked network can reduce the movement of the molecular chain segment, reduce the diffusion path of the corrosion medium, effectively prevent the penetration of moisture, oxygen, ions and other corrosion factors, and the methyl, phenyl and fluoroalkyl groups in the side chain further shield the main chain through hydrophobic interaction to reduce the penetration and attack of chemical media. The inorganic filler can form a physical barrier inside the material, so that the corrosion resistance of the prepared silicone rubber composition is further improved. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be described below. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0022] Embodiment 1, a preparation method of a corrosion-resistant silicone rubber composition, specifically comprising the following steps:

[0023] Step A1: mix dimethyl vinyl silanol lithium and tetrahydrofuran, protect with nitrogen, stir at a rotation speed of 200 r / min and a temperature of 0℃, add trifluoropropylmethylcyclotrisiloxane, heat to 25℃, react for 8h, then add modified filler, continue to react for 3h, to obtain modified additive;

[0024] Step A2: mix diphenyldimethoxysilane, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, hexamethyldisiloxane, tetramethylammonium hydroxide and deionized water, protect with nitrogen, react at a rotation speed of 200 r / min and a temperature of 90℃ for 10h, then heat to 105℃, react for 2h, heat to 150℃, and keep for 30min, to obtain polysiloxane;

[0025] Step A3: weigh the following raw materials: polysiloxane 80 parts, modified additive 5 parts and kast catalyst 0.03 parts, mix the raw materials uniformly and inject into a mold, react at a temperature of 30-40℃ for 20min, then heat to 160℃, continue to react for 40min, to obtain a corrosion-resistant silicone rubber composition.

[0026] The molar ratio of dimethyl vinyl silanol lithium, trifluoropropylmethylcyclotrisiloxane and Si-Cl bond on the modified filler in step A1 is 1:4:1.

[0027] The amount ratio of diphenyldimethoxysilane, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, hexamethyldisiloxane, tetramethylammonium hydroxide and deionized water in step A2 is 0.2 mol:2 mol:0.2 mol:1 mol:2 mol:40 mL.

[0028] The modified filler is prepared by the following steps:

[0029] Step B1: carbon nanotubes, concentrated sulfuric acid and concentrated nitric acid are mixed, and under the conditions of a rotation speed of 300 r / min and a temperature of 100 ℃, the mixture is reacted for 3 h, the filtrate is removed by filtration and dried to obtain carboxylated carbon nanotubes; thionyl chloride and N,N-dimethylformamide are uniformly mixed, and under the conditions of a rotation speed of 200 r / min and a temperature of 90 ℃, the mixture is stirred and the carboxylated carbon nanotubes are added, and the mixture is reacted for 4 h to obtain functionalized carbon nanotubes;

[0030] Step B2: boron nitride and urea are mixed and added to a ball mill, and under the conditions of a rotation speed of 500 r / min and a nitrogen atmosphere, the mixture is ball milled for 20 h, and then deionized water is added to uniformly mix the mixture, and the filtrate is removed by filtration and dried to obtain aminated boron nitride; the functionalized carbon nanotubes, the aminated boron nitride, triethylamine and N,N-dimethylformamide are mixed, and under the conditions of a rotation speed of 600 r / min and a temperature of 20 ℃, the mixture is reacted for 6 h to obtain a composite filler;

[0031] Step B3: the composite filler, acrylic acid, dicyclohexyl carbodiimide and N,N-dimethylformamide are mixed, and under the conditions of a rotation speed of 150 r / min and a temperature of 40 ℃, the mixture is reacted for 4 h to obtain a pretreated filler; the pretreated filler, methyldichlorosilane, Karstedt catalyst and N,N-dimethylformamide are mixed, and under the conditions of a rotation speed of 120 r / min and a temperature of 80 ℃, the mixture is reacted for 6 h under nitrogen protection to obtain a modified filler.

[0032] The amount ratio of carbon nanotubes, concentrated sulfuric acid and concentrated nitric acid in step B1 is 50 mg:3 mL:1 mL, the mass fraction of the concentrated sulfuric acid is 98%, the mass fraction of the concentrated nitric acid is 68%, and the amount ratio of thionyl chloride, N,N-dimethylformamide and carboxylated carbon nanotubes is 75 mL:1 mL:500 mg.

[0033] The mass ratio of boron nitride and urea in step B2 is 1:30, and the amount ratio of the functionalized carbon nanotubes, the aminated boron nitride, triethylamine and N,N-dimethylformamide is 100 mg:500 mg:0.3 mL:40 mL.

[0034] The molar ratio of the amino group, the acrylic acid and the dicyclohexyl carbodiimide on the composite filler in step B3 is 1:1:1, the molar ratio of the double bond on the pretreated filler and the methyldichlorosilane is 1:1, and the amount of the Karstedt catalyst is 0.01% of the mass of the methyldichlorosilane.

[0035] Embodiment 2, a preparation method of the corrosion-resistant silicone rubber composition, specifically comprising the following steps:

[0036] Step A1: mixing the lithium dimethylvinylsilanolate and the tetrahydrofuran, protecting by nitrogen, stirring at a rotation speed of 200 r / min and a temperature of 0℃, adding the trifluoropropylmethylcyclotrisiloxane, heating to 28℃, and reacting for 9 h, then adding the modified filler and continuing to react for 4 h to obtain the modified additive;

[0037] Step A2: mixing the diphenyldimethoxysilane, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, hexamethyldisiloxane, tetramethylammonium hydroxide and deionized water, protecting by nitrogen, stirring at a rotation speed of 200 r / min and a temperature of 95℃, reacting for 10 h, then heating to 110℃, reacting for 2 h, heating to 155℃, and keeping for 35 min to obtain the polysiloxane;

[0038] Step A3: weighing the following raw materials: 90 parts of the polysiloxane, 8 parts of the modified additive and 0.04 parts of the Karstedt catalyst, mixing the raw materials uniformly and injecting into a mold, reacting for 25 min at a temperature of 35℃, then heating to 165℃ and continuing to react for 45 min to obtain the corrosion-resistant silicone rubber composition.

[0039] The molar ratio of the lithium dimethylvinylsilanolate, the trifluoropropylmethylcyclotrisiloxane and the Si-Cl bond on the modified filler in step A1 is 1:4:1.

[0040] The amount ratio of the diphenyldimethoxysilane, the octamethylcyclotetrasiloxane, the tetramethylcyclotetrasiloxane, the hexamethyldisiloxane, the tetramethylammonium hydroxide and the deionized water in step A2 is 0.2 mol:2 mol:0.2 mol:1 mol:2 mol:40 mL.

[0041] The modified filler is prepared by the following steps:

[0042] Step B1: mixing the carbon nanotube, concentrated sulfuric acid and concentrated nitric acid, reacting for 4 h at a rotation speed of 300 r / min and a temperature of 105℃, removing the filtrate by filtration and drying to obtain the carboxylated carbon nanotube, mixing the sulfurous chloride and N,N-dimethylformamide uniformly, stirring at a rotation speed of 200 r / min and a temperature of 95℃, adding the carboxylated carbon nanotube, and reacting for 5 h to obtain the functionalized carbon nanotube.

[0043] Step B2: Boron nitride and urea were mixed and added to a ball mill, under the condition of 500 r / min rotation speed and nitrogen atmosphere, ball milling for 20 h, after adding deionized water and mixing uniformly, the filtrate was removed by filtration and dried to obtain aminated boron nitride, the functionalized carbon nanotubes, aminated boron nitride, triethylamine and N,N-dimethylformamide were mixed, under the condition of 800 r / min rotation speed and 20℃, the reaction was carried out for 7 h to obtain a composite filler;

[0044] Step B3: The composite filler, acrylic acid, dicyclohexyl carbodiimide and N,N-dimethylformamide were mixed, under the condition of 150 r / min rotation speed and 45℃, the reaction was carried out for 5 h to obtain a pretreated filler, the pretreated filler, methyldichlorosilane, Karstedt catalyst and N,N-dimethylformamide were mixed, and nitrogen was introduced for protection, under the condition of 120 r / min rotation speed and 85℃, the reaction was carried out for 7 h to obtain a modified filler.

[0045] The amount ratio of carbon nanotubes, concentrated sulfuric acid and concentrated nitric acid in step B1 was 50 mg:3 mL:1 mL, the mass fraction of concentrated sulfuric acid was 98%, the mass fraction of concentrated nitric acid was 68%, and the amount ratio of thionyl chloride, N,N-dimethylformamide and carboxylated carbon nanotubes was 75 mL:1 mL:500 mg.

[0046] The mass ratio of boron nitride and urea in step B2 was 1:30, and the amount ratio of functionalized carbon nanotubes, aminated boron nitride, triethylamine and N,N-dimethylformamide was 100 mg:500 mg:0.3 mL:40 mL.

[0047] The molar ratio of amino groups on the composite filler, acrylic acid and dicyclohexyl carbodiimide in step B3 was 1:1:1, the molar ratio of double bonds on the pretreated filler and methyldichlorosilane was 1:1, and the amount of Karstedt catalyst was 0.01% of the mass of methyldichlorosilane.

[0048] Example 3, a preparation method of a corrosion-resistant silicone rubber composition, specifically comprising the following steps:

[0049] Step A1: Dimethylvinylsilanol lithium and tetrahydrofuran were mixed, and nitrogen was introduced for protection, under the condition of 300 r / min rotation speed and 0℃, stirring and adding trifluoropropylmethylcyclotrisiloxane, and then the temperature was raised to 30℃, the reaction was carried out for 10 h, and then the modified filler was added and the reaction was continued for 5 h to obtain a modified additive;

[0050] Step A2: mixing diphenyl dimethoxysilane, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, hexamethyldisiloxane, tetramethylammonium hydroxide and deionized water, under the protection of nitrogen, under the condition of 300r / min of rotation speed and 95℃ of temperature, reacting for 15h, then under the condition of 110℃ of temperature, reacting for 3h, then under the condition of 160℃ of temperature, keeping for 40min, to obtain polysiloxane;

[0051] Step A3: weighing the raw materials as follows: 100 parts of polysiloxane, 10 parts of modified additive and 0.05 parts of Kist catalyst, mixing the raw materials uniformly and injecting into a mold, under the condition of 40℃ of temperature, reacting for 30min, then under the condition of 170℃ of temperature, continuing to react for 50min, to obtain the corrosion-resistant silicone rubber composition.

[0052] The molar ratio of dimethylvinylsilanol lithium, trifluoropropylmethylcyclotrisiloxane and Si-Cl bond on the modified filler in step A1 is 1:4:1.

[0053] The amount ratio of diphenyl dimethoxysilane, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, hexamethyldisiloxane, tetramethylammonium hydroxide and deionized water in step A2 is 0.2mol:2mol:0.2mol:1mol:2mol:40mL.

[0054] The modified filler is prepared by the following steps:

[0055] Step B1: mixing carbon nanotubes, concentrated sulfuric acid and concentrated nitric acid, under the condition of 500r / min of rotation speed and 110℃ of temperature, reacting for 5h, removing the filtrate by filtration and drying to obtain carboxylated carbon nanotubes, mixing sulfurous chloride and N,N-dimethylformamide uniformly, under the condition of 300r / min of rotation speed and 95℃ of temperature, stirring and adding carboxylated carbon nanotubes, reacting for 6h to obtain functionalized carbon nanotubes;

[0056] Step B2: mixing boron nitride and urea and adding into a ball mill, under the condition of 500r / min of rotation speed and nitrogen atmosphere, ball milling for 24h, adding deionized water and mixing uniformly, then removing the filtrate by filtration and drying to obtain aminated boron nitride, mixing functionalized carbon nanotubes, aminated boron nitride, triethylamine and N,N-dimethylformamide, under the condition of 800r / min of rotation speed and 25℃ of temperature, reacting for 8h to obtain the composite filler;

[0057] Step B3: the composite filler, acrylic acid, dicyclohexyl carbodiimide and N,N- dimethylformamide were mixed, and the pretreated filler was prepared by reacting at a rotation speed of 200 r / min and a temperature of 50℃ for 6h. The pretreated filler, methyldichlorosilane, Karstedt catalyst and N,N-dimethylformamide were mixed, and the modified filler was prepared by reacting at a rotation speed of 150 r / min and a temperature of 85℃ for 8h under nitrogen protection.

[0058] The carbon nanotubes, concentrated sulfuric acid and concentrated nitric acid in step B1 were used in a ratio of 50mg:3mL:1mL, the mass fraction of the concentrated sulfuric acid was 98%, the mass fraction of the concentrated nitric acid was 68%, and the amount of the thionyl chloride, N,N-dimethylformamide and carboxylated carbon nanotubes was in a ratio of 75mL:1mL:500mg.

[0059] The boron nitride and urea in step B2 were in a mass ratio of 1:30, and the amount of the functionalized carbon nanotubes, aminated boron nitride, triethylamine and N,N- dimethylformamide was in a ratio of 100mg:500mg:0.3mL:40mL.

[0060] The molar ratio of the amino group on the composite filler, the acrylic acid and the dicyclohexyl carbodiimide in step B3 was 1:1:1, the molar ratio of the double bond on the pretreated filler and the methyldichlorosilane was 1:1, and the amount of the Karstedt catalyst was 0.01% of the mass of the methyldichlorosilane.

[0061] Comparative Example 1: the same as Example 1 except that no diphenyldimethoxysilane was added.

[0062] Comparative Example 2: the same as Example 1 except that the aminated boron nitride was used instead of the composite filler.

[0063] Comparative Example 3: the same as Example 1 except that the hexamethylcyclotrisiloxane was used instead of the trifluoropropylmethylcyclotrisiloxane.

[0064] The silicone rubber compositions prepared in Examples 1-3 and Comparative Examples 1-3 were made into cubes with a size of 50mm×50mm×2mm, and were immersed in a 40% nitric acid solution and a 40% sodium hydroxide solution respectively at a temperature of 55℃ for 1 week according to the standard of GB / T11547-2008, and the test results are shown in Table 1.

[0065] Table 1

[0066]

[0067] As shown in Table 1, the application has good corrosion resistance.

[0068] The above merely illustrates and describes the concept of the present application, and those skilled in the art can make various modifications or supplements to the described specific embodiments or adopt similar ways to replace, as long as the modifications or supplements do not deviate from the concept of the present application or exceed the scope defined by the present claims, and the modifications or supplements shall fall within the protection scope of the present application.

Claims

1. A method for preparing a corrosion-resistant silicone rubber composition, characterized in that: Specifically, the steps include the following: Step A1: Mix lithium dimethylvinylsilane and tetrahydrofuran, purge with nitrogen, stir and add trifluoropropylmethylcyclotrisiloxane, heat and react, add modified filler and continue the reaction to obtain modified additive. Step A2: Mix diphenyldimethoxysilane, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, hexamethyldisiloxane, tetramethylammonium hydroxide and deionized water, purge with nitrogen gas, and react to obtain polysiloxane. Step A3: Weigh the following raw materials in parts by weight: 80-100 parts of polysiloxane, 5-10 parts of modified additives and 0.03-0.05 parts of caster catalyst. Mix the raw materials evenly and inject them into the mold. Heat the mixture to react and obtain a corrosion-resistant silicone rubber composition.

2. The method for preparing the corrosion-resistant silicone rubber composition according to claim 1, characterized in that: The molar ratio of lithium dimethylvinylsilane, trifluoropropylmethylcyclotrisiloxane, and the Si-Cl bond on the modified filler in step A1 is 1:4:

1.

3. The method for preparing the corrosion-resistant silicone rubber composition according to claim 1, characterized in that: The ratio of diphenyldimethoxysilane, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, hexamethyldisiloxane, tetramethylammonium hydroxide, and deionized water used in step A2 is 0.2 mol: 2 mol: 0.2 mol: 1 mol: 2 mol: 40 mL.

4. The method for preparing the corrosion-resistant silicone rubber composition according to claim 1, characterized in that: The modified filler is prepared by the following steps: Step B1: Carbon nanotubes, concentrated sulfuric acid and concentrated nitric acid are mixed and reacted, the filtrate is filtered to remove the filtrate and dried to obtain carboxylated carbon nanotubes. Thionyl chloride and N,N-dimethylformamide are mixed and stirred and then the carboxylated carbon nanotubes are added to react to obtain functionalized carbon nanotubes. Step B2: Mix boron nitride and urea and add them to a ball mill. Under a nitrogen atmosphere, ball mill the mixture. Add deionized water and mix evenly. Filter to remove the filtrate and dry to obtain aminated boron nitride. Mix and react functionalized carbon nanotubes, aminated boron nitride, triethylamine and N,N-dimethylformamide to obtain a composite filler. Step B3: The composite filler, acrylic acid, dicyclohexylcarbodiimide and N,N-dimethylformamide are mixed and reacted to obtain the pretreated filler. The pretreated filler, methyldichlorosilane, caster catalyst and N,N-dimethylformamide are mixed and reacted under nitrogen protection to obtain the modified filler.

5. The method for preparing the corrosion-resistant silicone rubber composition according to claim 4, characterized in that: In step B1, the ratio of carbon nanotubes, concentrated sulfuric acid, and concentrated nitric acid is 50 mg: 3 mL: 1 mL, and the ratio of thionyl chloride, N,N-dimethylformamide, and carboxylated carbon nanotubes is 75 mL: 1 mL: 500 mg.

6. The method for preparing the corrosion-resistant silicone rubber composition according to claim 4, characterized in that: In step B2, the mass ratio of boron nitride to urea is 1:30, and the ratio of functionalized carbon nanotubes, amino boron nitride, triethylamine, and N,N-dimethylformamide is 100mg:500mg:0.3mL:40mL.

7. The method for preparing the corrosion-resistant silicone rubber composition according to claim 4, characterized in that: The molar ratio of amino groups, acrylic acid, and dicyclohexylcarbodiimide on the composite filler described in step B3 is 1:1:1, and the molar ratio of double bonds and methyldichlorosilane on the pretreated filler is 1:

1.

8. A corrosion-resistant silicone rubber composition, characterized in that: Prepared according to any one of the preparation methods described in claims 1-7.

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