A silicone rubber cable material and its preparation method and application

Abstract

The present invention provides a silicone rubber cable material and a preparation method and application thereof. The raw materials for preparing the silicone rubber cable material include methyl vinyl silicone rubber, vinyl silicone oil, basalt fiber, white carbon black, a flame retardant and an additive. The basalt fiber is a basalt fiber modified by a silane coupling agent and montmorillonite. The silicone rubber cable material has the characteristics of good flexibility, high tensile strength and high tear strength.

Description

Technical Field

[0001] The invention belongs to the technical field of cable materials, and in particular relates to a silicone rubber cable material and a preparation method and application thereof. Background Art

[0002] Compared with traditional fuel vehicles, electric vehicles have added many high-voltage accessories, such as power batteries, high-voltage distribution boxes, drive motors, motor controllers, etc. This also puts forward new requirements for automotive cables. Cables are often arranged in the front cabin engine and chassis area, with the characteristics of high temperature, many bends, large wire diameter, and high heat generation. In addition, the road conditions are complex, and the cables need to have good wear resistance and mechanical strength. Therefore, the cable material needs to have good flexibility, flame retardancy, thermal conductivity, thermal stability, high and low temperature resistance, excellent bending resistance and high tear strength. At present, automotive power cable insulation materials include cross-linked polyolefins, thermoplastic elastomers and silicone rubber.

[0003] CN114763424A discloses a cross-linked polyolefin rubber and a preparation method, and an automotive cable using the same. The cross-linked polyolefin rubber, in parts by weight, comprises the following raw material components: 5-20 parts of nitrile rubber, 10-25 parts of ethylene-acrylate copolymer, 5-20 parts of polyethylene, 2-15 parts of polyolefin block copolymer, 2-15 parts of EPDM rubber, 3-5 parts of co-crosslinking agent, 2-10 parts of compatibilizer, 0.5-4 parts of composite antioxidant, and 0.5-2 parts of dispersant. The automotive cable made of the cross-linked polyolefin rubber provided by the technical solution can ensure good processing performance and elasticity, and also significantly improve the flexibility, precipitation resistance and anti-aging performance of the cable. After aging for 168 hours at 180°C, the mechanical property retention rate is good.

[0004] CN109825075A discloses a halogen-free flame-retardant thermoplastic elastomer cable material for new energy vehicles, which includes the following raw materials in parts by weight: 25-45 parts of thermoplastic elastomer, 10-40 parts of polyolefin, 5-25 parts of polyphenylene ether, 0.1-5 parts of halogen-free flame retardant, 1-5 parts of compatibilizer, 0.1-5 parts of antioxidant, and 5-10 parts of filler oil. The cable material provided by this technical solution has the properties of environmental protection and safety, flame retardancy, low smoke, and aging resistance.

[0005] CN109423052A discloses a silane cross-linked elastomeric cable material for high-voltage lines of new energy vehicles and a preparation method thereof. The silane cross-linked elastomeric cable material is composed of the following components in parts by weight: 15-35 parts of silicone rubber, 10-35 parts of ethylene-methyl acrylate, 10-25 parts of polyphosphazene, 10-30 parts of catalyst masterbatch, 10-20 parts of polyolefin, 2-10 parts of polyetheretherketone, 10-40 parts of phosphorus nitrogen flame retardant, 2-10 parts of silicon-based flame retardant synergist, 0.1-1 parts of vinyltrimethoxysilane, 1-10 parts of diisopropylbenzene peroxide, and 0.1-2 parts of antioxidant; wherein the catalyst masterbatch is composed of the following components in parts by weight: linear low-density polyethylene, di-n-butyltin dilaurate, triethylamine, siloxane, silicon dioxide, and antioxidant. The silane cross-linked elastomer cable material provided by this technical solution reaches a temperature resistance level of 150°C, and the mechanical property retention rate is above 80% after aging at 180°C × 7 days.

[0006] At present, cross-linked polyolefin materials in cable insulation materials are hard, inconvenient to install in the narrow space of the vehicle body, and the process is complicated, which is not suitable for cables with large wire diameters. Thermoplastic elastomer materials have low temperature resistance. Silicone rubber materials have good flexibility, good high and low temperature resistance, and strong voltage resistance, which are very suitable for the requirements of power vehicle cables, but the tensile strength, tear strength and flame retardant properties are low.

[0007] Therefore, it is necessary to develop a cable material with good flexibility, good temperature resistance, good flame retardancy, high tensile strength and high tear strength. Summary of the invention

[0008] In view of the shortcomings of the prior art, the present invention aims to provide a silicone rubber cable material and a preparation method and application thereof. The silicone rubber cable material is compounded with methyl vinyl silicone rubber, vinyl silicone oil, basalt fiber, white carbon black, flame retardant and additives, so that the obtained silicone rubber cable material has the characteristics of good flexibility, high tensile strength and high tear strength.

[0009] To achieve this object, the present invention adopts the following technical solutions:

[0010] In a first aspect, the present invention provides a silicone rubber cable material, wherein raw materials for preparing the silicone rubber cable material include methyl vinyl silicone rubber, vinyl silicone oil, basalt fiber, white carbon black, a flame retardant and an additive.

[0011] The present invention adopts methyl vinyl silicone rubber with good flexibility and high and low temperature resistance as a substrate, and prepares a cross-linked network structure by irradiating methyl vinyl silicone rubber and vinyl silicone oil. Basalt fiber and white carbon black are used as reinforcing agents. The prepared silicone rubber cable material has good flexibility, tensile strength and tear resistance.

[0012] Preferably, the raw materials for preparing the silicone rubber cable material include the following components in parts by weight:

[0013]

[0014] The mass fraction of the methyl vinyl silicone rubber can be 50 parts, 52 parts, 54 parts, 56 parts, 58 parts, 60 parts, 63 parts, 65 parts, 68 parts or 70 parts, etc.

[0015] The mass fraction of the vinyl silicone oil can be 1 part, 1.2 parts, 1.4 parts, 1.6 parts, 1.8 parts, 2 parts, 2.2 parts, 2.5 parts, 2.7 parts or 3 parts, etc.

[0016] The mass fraction of the basalt fiber can be 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts or 8 parts, etc.

[0017] The mass fraction of the white carbon black can be 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts or 19 parts, etc.

[0018] The mass fraction of the flame retardant can be 5 parts, 5.5 parts, 6 parts, 7 parts, 7.5 parts, 8 parts, 9 parts or 10 parts, etc.

[0019] The mass fraction of the auxiliary agent can be 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts or 5 parts, etc.

[0020] Preferably, the methyl vinyl silicone rubber includes methyl vinyl silicone rubber having a vinyl mole fraction of 0.35%-1% (for example, 0.35%, 0.38%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9% or 1%, etc.) and methyl vinyl silicone rubber having a vinyl mole fraction of 0.13%-0.2% (for example, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19% or 0.2%, etc.).

[0021] In the present invention, the side chain of the methyl vinyl silicone rubber has a vinyl group, and the methyl vinyl silicone rubber with a vinyl mole fraction of 0.13%-0.2% has good heat aging resistance and high temperature compression deformation resistance, and the methyl vinyl silicone rubber with a vinyl mole fraction of 0.35%-1% has high tear strength. The methyl vinyl silicone rubber with a vinyl mole fraction of 0.35%-1% and the methyl vinyl silicone rubber with a vinyl mole fraction of 0.13%-0.2% are matched to obtain a silicone rubber cable material with improved tear resistance while maintaining good heat aging resistance and high temperature compression deformation resistance.

[0022] Preferably, the mass ratio of the methyl vinyl silicone rubber with a vinyl mole fraction of 0.35%-1% and the methyl vinyl silicone rubber with a vinyl mole fraction of 0.13%-0.2% is 1-3:10, for example, 1:10, 1.2:10, 1.5:10, 1.7:10, 2:10, 2.2:10, 2.5:10, 2.7:10 or 3:10, etc.

[0023] Preferably, the basalt fibers are chopped fibers with a length of 1-3 mm, such as 1 mm, 1.2 mm, 1.5 mm, 1.7 mm, 2 mm, 2.3 mm, 2.5 mm, 2.7 mm, 2.8 mm or 3 mm.

[0024] In the present invention, the basalt fiber is a short-cut fiber with a length of 1-3 mm. If the length of the basalt fiber is too long, the flexibility of the silicone rubber cable material will decrease.

[0025] Preferably, the particle size of the montmorillonite is 10-50 nm, for example, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm or 50 nm.

[0026] Preferably, the preparation method of the silane coupling agent and montmorillonite modified basalt fiber comprises the following steps: mixing basalt fiber, montmorillonite and an aqueous solution of a silane coupling agent, reacting at 30-60°C (e.g., 30°C, 35°C, 38°C, 40°C, 45°C, 50°C, 55°C or 60°C, etc.) for 2-6h (e.g., 2h, 2.2h, 2.5h, 3h, 3.5h, 4h, 4.5h, 5h, 5.5h or 6h, etc.) to obtain a basalt fiber modified with a silane coupling agent and montmorillonite.

[0027] In the present invention, the basalt fiber has excellent mechanical properties, and can be compounded with silicone rubber to improve the mechanical properties, but the basalt fiber has a smooth surface and few chemically active sites, resulting in poor compatibility and interface bonding with silicone rubber, and poor effect on mechanical property enhancement. By modifying the basalt fiber with a silane coupling agent and montmorillonite, the surface structure of the basalt fiber is improved, the surface roughness is increased, and the mechanical properties are further improved.

[0028] Preferably, the silane coupling agent includes any one of 3-glycidyloxypropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-[3-(trimethoxysilyl)propyl]ethylenediamine, methacryloxytrimethoxysilane, and n-dodecyltrimethoxysilane, or a combination of at least two thereof.

[0029] Preferably, the mass ratio of the basalt fiber to montmorillonite is 10-20:1, for example, 10:1, 12:1, 13:1, 14:1, 15:1, 16:1, 17:1, 18:1, 19:1 or 20:1.

[0030] Preferably, the mass percentage concentration of the silane coupling agent aqueous solution is 0.5-2%, for example, 0.5%, 0.7%, 0.9%, 1.0%, 1.2%, 1.5%, 1.7%, 1.9% or 2%.

[0031] Preferably, the particle size of the white carbon black is 20-50 nm, for example, 20 nm, 25 nm, 28 nm, 30 nm, 32 nm, 35 nm, 38 nm, 40 nm, 45 nm or 50 nm.

[0032] The invention improves the tensile strength and tearing strength of the silicone rubber cable material through the synergistic effect of white carbon black and basalt fiber.

[0033] Preferably, the flame retardant comprises aluminum hydroxide and / or magnesium hydroxide.

[0034] Preferably, the auxiliary agent includes any one of an antioxidant, a heat stabilizer or a lubricant, or a combination of at least two of them.

[0035] Preferably, the auxiliary agent includes the following components in parts by weight: 0.5-2 parts of antioxidant (for example, 0.5 parts, 0.7 parts, 0.8 parts, 1 parts, 1.2 parts, 1.5 parts, 1.8 parts or 2 parts, etc.), 0.5-2 parts of heat stabilizer (for example, 0.5 parts, 0.7 parts, 0.8 parts, 1 parts, 1.2 parts, 1.5 parts, 1.8 parts or 2 parts, etc.) and 1-4 parts of lubricant (for example, 1 parts, 1.2 parts, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts or 4 parts, etc.).

[0036] Preferably, the antioxidant includes any one of 2,6-di-tert-butyl-4-methylphenol, bis(3,5-di-tert-butyl-4-hydroxyphenyl)sulfide or pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, or a combination of at least two thereof.

[0037] Preferably, the heat stabilizer is any one of calcium stearate, barium stearate or zinc stearate, or a combination of at least two of them.

[0038] Preferably, the lubricant comprises silicone masterbatch.

[0039] In a second aspect, the present invention provides a method for preparing the silicone rubber cable material as described in the first aspect, characterized in that the preparation method comprises the following steps:

[0040] (1) Methyl vinyl silicone rubber, vinyl silicone oil, basalt fiber, white carbon black, flame retardant and additives are mixed and extruded to obtain blended particles.

[0041] (2) The blended particles obtained in step (1) are made into wires, and the wires are then irradiated and cross-linked to obtain the silicone rubber cable material.

[0042] Preferably, the mixing method in step (1) is internal mixing.

[0043] Preferably, the kneading temperature is 110-140°C, such as 110°C, 115°C, 120°C, 125°C, 130°C, 135°C or 140°C.

[0044] Preferably, the mixing time in step (1) is 15-25 min, for example, 15 min, 16 min, 17 min, 18 min, 19 min, 20 min, 21 min, 22 min, 24 min or 25 min.

[0045] Preferably, the extrusion method in step (1) is single-screw extruder extrusion.

[0046] Preferably, the temperature of the feeding zone of the single screw extruder in step (1) is 100-110°C (e.g., 100°C, 101°C, 102°C, 103°C, 105°C, 106°C, 107°C, 109°C or 110°C), and the temperature of the conveying zone is 120-130°C (e.g., 120°C, 121°C, 122°C, 123°C, 125°C, 126°C, 127°C, 128°C, 129°C, 130°C, 131°C, 132°C, 133°C, 134°C, 135°C, 136°C, 137°C, 138°C, 139°C, 140°C, 141°C, 142°C, 143°C, 144°C, 145°C, 146°C, 147°C, 148°C, 149°C, 150°C, 9°C or 130°C, etc.), the temperature of the heating zone is 130-140°C (for example, 130°C, 131°C, 132°C, 133°C, 135°C, 136°C, 137°C, 139°C or 140°C, etc.), and the head temperature is 135-145°C (for example, 135°C, 136°C, 137°C, 138°C, 140°C, 142°C, 143°C, 144°C or 145°C, etc.).

[0047] Preferably, the making of the wire in step (2) is carried out by a wire extruder.

[0048] Preferably, the temperature of the feeding zone of the wire extruder is 110-130°C (e.g., 110°C, 112°C, 113°C, 115°C, 118°C, 120°C, 124°C, 126°C or 130°C, etc.), and the temperature of the conveying zone is 155-170°C (e.g., 155°C, 158°C, 160°C, 162°C, 165°C, 167°C, 168°C, 169°C or 170℃, etc.), the temperature of the heating zone is 160-175℃ (for example, 160℃, 162℃, 165℃, 168℃, 169℃, 170℃, 172℃, 174℃ or 175℃, etc.), and the head temperature is 170-180℃ (for example, 170℃, 172℃, 174℃, 175℃, 176℃, 177℃, 178℃, 179℃ or 180℃, etc.).

[0049] Preferably, the irradiation in step (2) is performed by an electron accelerator, and the irradiation dose is 5-15 Mrad, for example, 5 Mrad, 6 Mrad, 7 Mrad, 8 Mrad, 9 Mrad, 10 Mrad, 12 Mrad, 14 Mrad or 15 Mrad, etc.

[0050] In a third aspect, the present invention provides a use of the silicone rubber cable material as described in the first aspect as an insulating material for a cable line.

[0051] Compared with the prior art, the present invention has the following beneficial effects:

[0052] The silicone rubber cable material prepared by compounding methyl vinyl silicone rubber, vinyl silicone oil, basalt fiber, white carbon black, flame retardant and additives has the characteristics of good flexibility, good temperature resistance, good flame retardancy, high tensile strength and tear strength, with the tensile strength being ≥11.7MPa and the tear strength being ≥21KN / m. DETAILED DESCRIPTION

[0053] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0054] The raw material models and manufacturers of the following examples and comparative examples are as follows:

[0055] Methyl vinyl silicone rubber with a vinyl molar fraction of 0.5%-0.79%, 110-5S, purchased from Dongjue Silicone Group Co., Ltd.

[0056] Methyl vinyl silicone rubber with a vinyl molar fraction of 0.13%-0.2%, 110-2, purchased from Dongjue Silicone Group Co., Ltd.

[0057] Vinyl silicone oil, MY1203V, purchased from Anhui Mingyi Silicon Industry Co., Ltd.

[0058] Silicone masterbatch, GT500, purchased from Zhejiang Jiahua Co., Ltd.

[0059] Example 1

[0060] The present embodiment provides a silicone rubber cable material and a preparation method thereof. The raw materials for preparing the silicone rubber cable material include the following components in parts by weight: 60 parts of methyl vinyl silicone rubber (methyl vinyl silicone rubber is 110-5S and 110-2 with a mass ratio of 2:10), 2 parts of vinyl silicone oil (MY1203V), 5 parts of silane coupling agent and montmorillonite-modified basalt fiber (length 2 mm), 15 parts of white carbon black (particle size 25 nm), 8 parts of flame retardant (aluminum hydroxide) and 3 parts of additives.

[0061] The auxiliary agent is 0.5 parts of antioxidant (2,6-di-tert-butyl-4-methylphenol), 1 part of heat stabilizer (calcium stearate) and 1.5 parts of lubricant (silicone masterbatch, GT500).

[0062] The preparation method of the silane coupling agent and montmorillonite modified basalt fiber is as follows:

[0063] Basalt fiber and montmorillonite in a mass ratio of 15:1 were added to a silane coupling agent (3-glycidyloxypropyltrimethoxysilane) aqueous solution with a mass percentage concentration of 1%, mixed, reacted at 50°C for 4 hours, filtered, and dried at 120°C for 1 hour to obtain basalt fiber modified with silane coupling agent and montmorillonite.

[0064] The preparation method comprises the following steps:

[0065] (1) Methyl vinyl silicone rubber, vinyl silicone oil, silane coupling agent, montmorillonite-modified basalt fiber, white carbon black, flame retardant and additives were mixed at 130° C. for 20 min, and then extruded through a single screw extruder. The temperature of the feeding zone of the single screw extruder was 105° C., the temperature of the conveying zone was 125° C., the temperature of the heating zone was 135° C., and the temperature of the die head was 140° C. to obtain blended particles.

[0066] (2) adding the blended particles obtained in step (1) to a wire extruder, wherein the temperature of the feeding zone of the wire extruder is 120° C., the temperature of the conveying zone is 160° C., the temperature of the heating zone is 170° C., and the temperature of the die head is 175° C. After obtaining the wire, an electron accelerator is used to perform irradiation cross-linking, and the irradiation dose is 10 Mrad to obtain the silicone rubber cable material.

[0067] Example 2

[0068] This embodiment provides a silicone rubber cable material and a preparation method thereof. The raw materials for preparing the silicone rubber cable material include the following components in parts by weight:

[0069] 50 parts of methyl vinyl silicone rubber (methyl vinyl silicone rubber is 110-5S and 110-2 with a mass ratio of 1:10), 1 part of vinyl silicone oil (MY1203V), 1 part of silane coupling agent and montmorillonite-modified basalt fiber (length 1mm), 10 parts of white carbon black (particle size 20nm), 5 parts of flame retardant (magnesium hydroxide), and 1 part of additive (silicone masterbatch, GT500).

[0070] The preparation method of the silane coupling agent and montmorillonite modified basalt fiber is as follows:

[0071] Basalt fiber and montmorillonite in a mass ratio of 10:1 were added to a silane coupling agent (3-aminopropyltriethoxysilane) aqueous solution with a mass percentage concentration of 0.5%, mixed, reacted at 30°C for 6 hours, filtered, and dried at 120°C for 1 hour to obtain basalt fiber modified with silane coupling agent and montmorillonite.

[0072] The preparation method comprises the following steps:

[0073] (1) Methyl vinyl silicone rubber, vinyl silicone oil, silane coupling agent, montmorillonite-modified basalt fiber, white carbon black, flame retardant and additives were mixed at 110° C. for 25 min, and then extruded through a single screw extruder. The temperature of the feeding zone of the single screw extruder was 110° C., the temperature of the conveying zone was 120° C., the temperature of the heating zone was 130° C., and the temperature of the die head was 135° C. to obtain blended particles.

[0074] (2) adding the blended particles obtained in step (1) to a wire extruder, wherein the temperature of the feeding zone of the wire extruder is 130° C., the temperature of the conveying zone is 155° C., the temperature of the heating zone is 160° C., and the temperature of the die head is 170° C. After obtaining the wire, an electron accelerator is used to perform irradiation cross-linking, and the irradiation dose is 15 Mrad to obtain the silicone rubber cable material.

[0075] Example 3

[0076] This embodiment provides a silicone rubber cable material and a preparation method thereof. The raw materials for preparing the silicone rubber cable material include the following components in parts by weight:

[0077] 70 parts of methyl vinyl silicone rubber (methyl vinyl silicone rubber is 110-5S and 110-2 with a mass ratio of 3:10), 3 parts of vinyl silicone oil (MY1203V), 8 parts of silane coupling agent and montmorillonite-modified basalt fiber (length 3mm), 20 parts of white carbon black (particle size 50nm), 10 parts of flame retardant (aluminum hydroxide) and 5 parts of additives.

[0078] The auxiliary agent is 2 parts of a heat stabilizer (zinc stearate) and 3 parts of a lubricant (silicone masterbatch, GT500).

[0079] The preparation method of the silane coupling agent and montmorillonite modified basalt fiber is as follows:

[0080] Basalt fiber and montmorillonite in a mass ratio of 20:1 were added to a silane coupling agent (methacryloxytrimethoxysilane) aqueous solution with a mass percentage concentration of 2%, mixed, reacted at 60°C for 2h, filtered, and dried at 120°C for 1h to obtain basalt fiber modified with silane coupling agent and montmorillonite.

[0081] The preparation method comprises the following steps:

[0082] (1) Methyl vinyl silicone rubber, vinyl silicone oil, basalt fiber, white carbon black, flame retardant and additives were mixed at 140° C. for 15 min, and then extruded through a single screw extruder. The temperature of the feeding zone of the single screw extruder was 110° C., the temperature of the conveying zone was 130° C., the temperature of the heating zone was 140° C., and the temperature of the die was 145° C. to obtain blended particles.

[0083] (2) adding the blended particles obtained in step (1) to a wire extruder, wherein the temperature of the feeding zone of the wire extruder is 130° C., the temperature of the conveying zone is 170° C., the temperature of the heating zone is 175° C., and the temperature of the die head is 180° C. After obtaining the wire, an electron accelerator is used to perform irradiation cross-linking, and the irradiation dose is 5 Mrad to obtain the silicone rubber cable material.

[0084] Example 4

[0085] This embodiment provides a silicone rubber cable material and a preparation method thereof. The difference between this embodiment and embodiment 1 is that the methyl vinyl silicone rubber is 110-2, and other raw materials, amounts and preparation methods are the same as those in embodiment 1.

[0086] Example 5

[0087] This embodiment provides a silicone rubber cable material and a preparation method thereof. The difference between this embodiment and embodiment 1 is that the mass of white carbon black is 5 parts, and other raw materials, dosages and preparation methods are the same as those in embodiment 1.

[0088] Example 6

[0089] This embodiment provides a silicone rubber cable material and a preparation method thereof. The difference between this embodiment and embodiment 1 is that white carbon black (particle size is 25 nm) is replaced by white carbon black (particle size is 200 nm) of the same mass, and other raw materials, amounts and preparation methods are the same as those in embodiment 1.

[0090] Comparative Example 1

[0091] This embodiment provides a silicone rubber cable material and a preparation method thereof. The difference between this embodiment and Example 1 is that the basalt fiber (length 2 mm) modified with a silane coupling agent and montmorillonite is replaced with a basalt fiber (length 2 mm) of the same mass that is not modified with a silane coupling agent and montmorillonite, and the other raw materials, amounts and preparation methods are the same as those in Example 1.

[0092] Comparative Example 2

[0093] This comparative example provides a silicone rubber cable material and a preparation method thereof, which differs from Example 1 in that no silane coupling agent and montmorillonite-modified basalt fiber are added, 20 parts by mass of white carbon black are added, and other raw materials, amounts and preparation methods are the same as those in Example 1.

[0094] Comparative Example 3

[0095] This comparative example provides a silicone rubber cable material and a preparation method thereof. The difference between it and Example 1 is that no white carbon black is added, and the mass fraction of silane coupling agent and montmorillonite-modified basalt fiber (length 2 mm) added is 20 parts, and other raw materials, amounts and preparation methods are the same as those in Example 1.

[0096] Comparative Example 4

[0097] This comparative example provides a silicone rubber cable material and a preparation method thereof, which differs from Example 1 in that white carbon black and basalt fiber are not added, and other raw materials, amounts and preparation methods are the same as those in Example 1.

[0098] Comparative Example 5

[0099] This comparative example provides a silicone rubber cable material and a preparation method thereof. The difference between the comparative example and Example 1 is that the silane coupling agent and the montmorillonite-modified basalt fiber are replaced with the same mass of silane coupling agent-modified basalt fiber and silane coupling agent-modified montmorillonite. The preparation method of the silane coupling agent-modified basalt fiber is as follows:

[0100] 15 parts of basalt fiber were added to a 1% by mass concentration of a silane coupling agent (3-glycidyloxypropyltrimethoxysilane) aqueous solution, mixed, reacted at 50° C. for 4 hours, filtered, and dried at 120° C. for 1 hour to obtain basalt fiber modified with a silane coupling agent.

[0101] One portion of montmorillonite was added to a 1% by mass concentration of a silane coupling agent (3-glycidyloxypropyltrimethoxysilane) aqueous solution, mixed, reacted at 50° C. for 4 hours, filtered, and dried at 120° C. for 1 hour to obtain montmorillonite-modified basalt fiber.

[0102] Other raw materials, dosage and preparation method are the same as those in Example 1.

[0103] Performance Testing

[0104] The following performance tests were performed on the silicone rubber cable materials provided in the embodiments and comparative examples.

[0105] (1) Tensile strength and elongation at break: The test shall be conducted in accordance with the test methods for tensile strength and elongation at break in GB / T2951 General test methods for insulation and sheath materials of electric and optical cables.

[0106] (2) Tear strength: Tested according to the test method of GB / T529 “Determination of tear strength of vulcanized rubber or thermoplastic rubber”.

[0107] The test results are shown in Table 1.

[0108] Table 1

[0109]

[0110] According to the test results in Table 1, the tensile strength of the silicone rubber cable material provided in Examples 1 to 6 is 11.7-14.7 MPa, and the tear strength is 21-35 KN / m.

[0111] Compared with Example 1, if the basalt fiber (length of 2 mm) modified with silane coupling agent and montmorillonite is replaced with basalt fiber (length of 2 mm) of the same mass (Comparative Example 1), both the tensile strength and the tear strength decrease.

[0112] Compared with Example 1, if basalt fiber is not added (Comparative Example 2), the tensile strength is greatly reduced and the tear strength is reduced.

[0113] Compared with Example 1, if white carbon black is not added (Comparative Example 3), both the tensile strength and the tear strength decrease.

[0114] Compared with Example 1, without white carbon black and basalt fiber (Comparative Example 4), both tensile strength and tear strength decrease.

[0115] Compared with Example 1, if the basalt fiber modified with silane coupling agent and montmorillonite is replaced with basalt fiber modified with silane coupling agent and montmorillonite modified with silane coupling agent of the same mass (Comparative Example 5), the tensile strength and tear strength are both reduced. The reason is that, for the basalt fiber modified with silane coupling agent and montmorillonite, montmorillonite is distributed on the surface of the basalt fiber, and the bonding effect is good, so that the surface of the basalt fiber has both the modification effect of the silane coupling agent and the roughness increased by the distribution of montmorillonite, and the bonding effect with the polymer matrix is ​​better, and the crack propagation inhibition effect is better during the stretching and tearing process.

[0116] The applicant declares that the present invention uses the above-mentioned embodiments to illustrate a silicone rubber cable material and its preparation method and application, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A silicone rubber cable material, characterized in that: The raw materials for preparing the silicone rubber cable material include methyl vinyl silicone rubber, vinyl silicone oil, basalt fiber, white carbon black, flame retardant and additives; The basalt fiber is a basalt fiber modified by a silane coupling agent and montmorillonite; The basalt fiber is a chopped fiber with a length of 1-3 mm; The preparation method of the silane coupling agent and montmorillonite modified basalt fiber comprises the following steps: mixing basalt fiber, montmorillonite and a silane coupling agent aqueous solution, reacting at 30-60° C. for 2-6 hours, to obtain the silane coupling agent and montmorillonite modified basalt fiber; The raw materials for preparing the silicone rubber cable material include the following components by weight: Methyl vinyl silicone rubber 50-70 parts 1-3 parts of vinyl silicone oil Basalt fiber 1-8 parts 10-20 parts of white carbon black Flame retardant 5-10 parts 1-5 parts of additives; The particle size of the white carbon black is 20-50nm; The preparation method of the silicone rubber cable material comprises the following steps: (1) mixing and extruding methyl vinyl silicone rubber, vinyl silicone oil, basalt fiber, white carbon black, flame retardant and additives to obtain blended particles; (2) The blended particles obtained in step (1) are made into wires, and the wires are then irradiated and cross-linked to obtain the silicone rubber cable material.

2. The silicone rubber cable material according to claim 1, characterized in that: The methyl vinyl silicone rubber includes methyl vinyl silicone rubber with a vinyl mole fraction of 0.35%-1% and methyl vinyl silicone rubber with a vinyl mole fraction of 0.13%-0.2%.

3. The silicone rubber cable material according to claim 2, characterized in that: The mass ratio of the methyl vinyl silicone rubber with a vinyl mole fraction of 0.35%-1% to the methyl vinyl silicone rubber with a vinyl mole fraction of 0.13%-0.2% is 1-3:

10.

4. The silicone rubber cable material according to claim 1, characterized in that: The particle size of the montmorillonite is 10-50 nm.

5. The silicone rubber cable material according to claim 1, characterized in that: The silane coupling agent includes any one of 3-glycidyloxypropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-[3-(trimethoxysilyl)propyl]ethylenediamine, methacryloxytrimethoxysilane, and n-dodecyltrimethoxysilane, or a combination of at least two thereof.

6. The silicone rubber cable material according to claim 1, characterized in that: The mass ratio of the basalt fiber to montmorillonite is 10-20:

1.

7. The silicone rubber cable material according to claim 1, characterized in that: The mass percentage concentration of the silane coupling agent aqueous solution is 0.5-2%.

8. The silicone rubber cable material according to claim 1, characterized in that: The flame retardant includes aluminum hydroxide and / or magnesium hydroxide.

9. The silicone rubber cable material according to claim 1, characterized in that: The auxiliary agent includes any one of an antioxidant, a heat stabilizer or a lubricant, or a combination of at least two of them.

10. The silicone rubber cable material according to claim 1, characterized in that: The auxiliary agent comprises the following components in parts by weight: 0.5-2 parts of antioxidant, 0.5-2 parts of heat stabilizer and 1-4 parts of lubricant.

11. The silicone rubber cable material according to claim 10, characterized in that: The antioxidant includes any one of 2,6-di-tert-butyl-4-methylphenol, bis(3,5-di-tert-butyl-4-hydroxyphenyl) sulfide or pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate or a combination of at least two thereof.

12. The silicone rubber cable material according to claim 10, characterized in that: The heat stabilizer is any one of calcium stearate, barium stearate or zinc stearate, or a combination of at least two of them.

13. The silicone rubber cable material according to claim 10, characterized in that: The lubricant includes silicone masterbatch.

14. The method for preparing a silicone rubber cable material according to any one of claims 1 to 13, characterized in that: The preparation method comprises the following steps: (1) mixing and extruding methyl vinyl silicone rubber, vinyl silicone oil, basalt fiber, white carbon black, flame retardant and additives to obtain blended particles; (2) The blended particles obtained in step (1) are made into wires, and the wires are then irradiated and cross-linked to obtain the silicone rubber cable material.

15. The method for preparing a silicone rubber cable material according to claim 14, characterized in that: The mixing method in step (1) is internal mixing.

16. The method for preparing a silicone rubber cable material according to claim 14, characterized in that: The mixing temperature is 110-140°C.

17. The method for preparing a silicone rubber cable material according to claim 14, characterized in that: The mixing time in step (1) is 15-25 minutes.

18. The method for preparing a silicone rubber cable material according to claim 14, characterized in that: The extrusion method in step (1) is single screw extruder extrusion.

19. The method for preparing a silicone rubber cable material according to claim 18, characterized in that: The temperature of the feeding zone of the single screw extruder in step (1) is 100-110°C, the temperature of the conveying zone is 120-130°C, the temperature of the heating zone is 130-140°C, and the temperature of the die head is 135-145°C.

20. The method for preparing a silicone rubber cable material according to claim 14, characterized in that: The wire making in step (2) is carried out by a wire extruder.

21. The method for preparing a silicone rubber cable material according to claim 20, characterized in that: The temperature of the feeding zone of the wire extruder is 110-130°C, the temperature of the conveying zone is 155-170°C, the temperature of the heating zone is 160-175°C, and the temperature of the die head is 170-180°C.

22. The method for preparing a silicone rubber cable material according to claim 14, characterized in that: The irradiation in step (2) is carried out by an electron accelerator, and the irradiation dose is 5-15 Mrad.

23. Use of the silicone rubber cable material according to any one of claims 1 to 13 as a cable insulation material.

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