A heat-resistant, interference-resistant, and tensile-resistant control cable

Abstract

This invention relates to the field of cable technology and discloses a heat-resistant, interference-resistant, and tensile-resistant control cable. The heat-resistant, interference-resistant, and tensile-resistant control cable of this invention comprises a reinforced core, a conductor, an insulation layer, a shielding layer, a filler layer, and a rubber outer sheath. The rubber outer sheath comprises 60-90 parts by weight of EPDM rubber, 10-40 parts by weight of fluororubber, 15-30 parts by weight of reinforcing agent, 5-20 parts by weight of modified zinc oxide whiskers, 1.6-2.3 parts by weight of vulcanizing agent, and 1.8-2.6 parts by weight of crosslinking agent. The modified zinc oxide whiskers are uniformly dispersed in the EPDM rubber and fluororubber blend matrix, providing better reinforcement and significantly improving the tensile strength and tear strength of the rubber outer sheath. Furthermore, it has a high thermal decomposition temperature and good heat resistance.

Description

Technical Field

[0001] This invention relates to the field of cable technology, specifically to a heat-resistant, interference-resistant, and tensile-resistant control cable. Background Technology

[0002] Control cables are key transmission components in industrial automation systems, primarily used to transmit control signals, detection signals, and command information. They are widely used in industries such as metallurgy, chemical engineering, power generation, and mining. As industrial production moves towards higher temperatures, higher pressures, and stronger interference, existing control cables are increasingly revealing numerous shortcomings. Traditional control cables, with sheaths made of polyethylene or polyvinyl chloride, have poor heat resistance and high-temperature aging resistance, and limited mechanical strength. During cable laying, dragging, and equipment vibration, tensile forces often cause conductor breakage and shielding damage, shortening cable lifespan. Therefore, developing heat-resistant, high-mechanical-strength sheaths and corresponding control cables is of great significance.

[0003] Currently, the main materials for the sheathing of control cables are plastics and rubber. Among them, EPDM rubber has good resistance to high and low temperatures and corrosion, but its mechanical strength and flame retardancy are relatively poor. Fluororubber has strong flame retardancy and high resistance to heat, aging and weathering, but its mechanical properties are not good. Blends of EPDM rubber and fluororubber can combine the advantages of both and have wide practical applications in cable sheathing.

[0004] Zinc oxide whiskers possess advantages such as high strength, high modulus, high wear resistance, and high temperature resistance. When added to materials such as EPDM rubber and fluororubber, they can improve their mechanical strength, wear resistance, and heat resistance. Patent CN110922687B discloses a modified nano-zinc oxide / EPDM rubber-based cable accessory material and its preparation method. It utilizes ferric nitrate to modify nano-zinc oxide, which can improve the nonlinear coefficient and breakdown field strength of the EPDM rubber-based cable accessory material, thereby increasing the service life of the cable accessory material. However, this patent does not improve the compatibility between zinc oxide and EPDM rubber or fluororubber, which is not conducive to improving the mechanical strength and other properties of the rubber material. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a heat-resistant, interference-resistant, and tensile-resistant control cable with a rubber sheath layer, which solves the problems of low heat resistance and strength of the cable sheath layer.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a heat-resistant, interference-resistant, and tensile-resistant control cable, which is composed of a reinforced cable core, a conductor, an insulation layer, a shielding layer, a filling layer, and a rubber outer sheath.

[0007] The rubber outer sheath material includes 60-90 parts by weight of EPDM rubber, 10-40 parts by weight of fluororubber, 15-30 parts by weight of reinforcing agent, 5-20 parts by weight of modified zinc oxide whiskers, 3-4.2 parts by weight of lubricant, 1.6-2.3 parts by weight of vulcanizing agent, 1.8-2.6 parts by weight of crosslinking agent, and 1-3.5 parts by weight of acid absorber.

[0008] The preparation method of the rubber outer sheath material is as follows:

[0009] (1) Add 1,4-dioxane, epoxidized soybean oil, pentafluoropropionic acid and tetrabutylammonium bromide to a flask, react, dilute with water, extract with chloroform, separate, distill under reduced pressure and dry to obtain fluorinated soybean oil.

[0010] (2) Add 1,4-dioxane, fluorinated soybean oil, and 1,3-propanesulfonate lactone to a flask, add sodium hydroxide solution dropwise, and allow the reaction to proceed. After the reaction is complete, evaporate by rotary evaporation to precipitate the precipitate. Filter the precipitate, wash it with petroleum ether, and dry it to obtain the dispersant. The preparation reaction formula is:

[0011] .

[0012] (3) Add isopropanol, water, zinc oxide whiskers and dispersant to a high-speed mixer, disperse, filter, wash the solid with isopropanol and water to obtain modified zinc oxide whiskers.

[0013] (4) Add EPDM rubber and fluororubber to an open mill for plasticizing, then add reinforcing agent, modified zinc oxide whiskers, acid absorber and lubricant, mix, and finally add vulcanizing agent and crosslinking agent. After mixing, place the material in a flat vulcanizing machine for first-stage vulcanization, and then place it in a blower drying oven for second-stage vulcanization to obtain rubber outer sheath material.

[0014] Preferably, the reinforcing core is located at the exact center of the cable's cross-section, and the conductors are arranged in a ring-shaped twist around the reinforcing core.

[0015] Preferably, the reinforcing cable core is an aramid fiber bundle with a diameter of 1.2-2.0 mm.

[0016] Preferably, the conductor is made of 7-19 strands of tin-plated copper wire with a diameter of 0.15-0.3mm, and the stranding pitch is 10-15 times the outer diameter of the conductor.

[0017] Preferably, the insulation layer is made of polyvinyl chloride or polyetheretherketone material with a thickness of 0.8-1.5 mm.

[0018] Preferably, the shielding layer includes an inner braided shielding layer and an outer aluminum-plastic composite tape wrapping shielding layer. The inner braided shielding layer is woven with silver-plated copper wire with a braiding density of 90-92%, and the outer aluminum-plastic composite tape wrapping layer has an overlap rate of 25-28%.

[0019] Preferably, the filler layer is a ceramicized silicone rubber rope with a filler coefficient of 90-95%.

[0020] Preferably, the reinforcing agent is one or more of carbon black, silica, and calcium carbonate; the acid absorbent is one or more of calcium hydroxide and magnesium oxide.

[0021] Preferably, the lubricant is paraffin oil.

[0022] Preferably, the vulcanizing agent is dicumyl peroxide.

[0023] Preferably, the crosslinking agent is triallyl isocyanurate.

[0024] Preferably, in (1), the amount of epoxidized soybean oil is 100 parts by weight, pentafluoropropionic acid is 50-84 parts by weight, and tetrabutylammonium bromide is 0.7-1 parts by weight.

[0025] Preferably, the reaction in (1) is carried out at 95-110℃ for 10-16h.

[0026] Preferably, (2) the amount of fluorinated soybean oil is 100 parts by weight and the amount of 1,3-propanesulfonate lactone is 26-36 parts by weight.

[0027] Preferably, the reaction in (2) is carried out at 70-90℃ for 6-10h.

[0028] Preferably, in (3), the amount of zinc oxide whiskers is 100 parts by weight and the amount of dispersant is 1.5-4 parts by weight.

[0029] Preferably, (3) the temperature inside the medium-speed mixer is 75-90℃, the rotation speed is 800-1200rpm, and the dispersion time is 1-2h.

[0030] Preferably, in (4), the first stage of vulcanization is carried out at 165-175℃ for 10-15 min, and the second stage of vulcanization is carried out at 150-155℃ for 5-8 h.

[0031] The beneficial technical effects of this invention are as follows: The conductor is made of multiple strands of tin-plated copper wire, which ensures the conductor's conductivity, improves its flexibility and fatigue resistance, and the tin plating layer effectively prevents copper wire oxidation, extending the conductor's service life. The reinforcing core, located at the center of the cable, is made of aramid fiber bundles. Aramid fibers are characterized by ultra-high strength and lightweight, serving as a central tensile skeleton to withstand tensile forces during cable laying and use, preventing damage to the conductor and shielding layer due to stress, and thus improving the cable's tensile strength.

[0032] This invention uses materials such as polyetheretherketone (PEEK) and polyvinyl chloride (PVC) as the insulating layer, which is extruded onto the outside of the conductor. PEEK has a wide temperature range and high Shore hardness, and has excellent high temperature resistance, wear resistance and insulation properties, which can effectively prevent the insulation layer from aging and failing under high temperature environment.

[0033] This invention adopts a composite structure of "inner braided shielding + outer aluminum-plastic composite tape wrapping shielding". The inner braided shielding is made of silver-plated copper wire, which has excellent conductivity and shielding effect and can effectively block low-frequency electromagnetic interference. The outer aluminum-plastic composite tape wrapping shielding can enhance the shielding ability against high-frequency electromagnetic radiation. The dual shielding structure works together to ensure the stable transmission of control signals.

[0034] This invention uses ceramicized silicone rubber rope to fill the space between the insulating core and the shielding layer. The ceramicized silicone rubber rope has good elasticity and high temperature resistance. When exposed to fire, it can quickly form a dense ceramicized hard shell, which plays a role in fire prevention, smoke isolation and heat insulation. At the same time, the filling layer can make the cable structure more rounded and reduce mechanical damage during use.

[0035] This invention uses a blend of EPDM rubber and fluororubber as the outer rubber sheath material, and adds zinc oxide whiskers modified with a dispersant for reinforcement. The dispersant contains multiple sulfonate groups, which can adsorb onto the surface of the zinc oxide whiskers, modifying the surface and acting as a steric hindrance to reduce the aggregation of zinc oxide whiskers. At the same time, the dispersant contains long carbon chains, which can improve the compatibility between zinc oxide whiskers and EPDM rubber, and the dispersant contains multiple fluorine-containing groups, which can improve the compatibility between zinc oxide whiskers and fluororubber. This allows the zinc oxide whiskers to be uniformly dispersed in the blended rubber matrix, providing better reinforcement and significantly improving the tensile strength and tear strength of the rubber sheath material. It also has a high thermal decomposition temperature and good heat resistance. Detailed Implementation

[0036] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0037] The following are product specifications: EPDM 2032PM (EPR rubber), manufactured by Guangdong Boruida Polymer Technology; FKMJHF-246G (fluororubber), manufactured by Dongguan Caihua Plastics Technology; and SS-ZJ50 (zinc oxide whiskers), manufactured by Hangzhou Jikang New Materials.

[0038] Example 1: A heat-resistant, interference-resistant, and tensile-resistant control cable, comprising a reinforcing core, conductor, insulation layer, shielding layer, filler layer, and rubber outer sheath. The reinforcing core is located at the center of the cable's cross-section, and the conductor is arranged in a ring-like twisted configuration around the reinforcing core. The reinforcing core is an aramid fiber bundle with a diameter of 1.5 mm. The conductor is composed of 12 strands of tin-plated copper wire with a diameter of 0.2 mm, with a twist pitch 10 times the conductor's outer diameter. The insulation layer is made of polyvinyl chloride with a thickness of 0.8 mm. The shielding layer includes an inner braided shielding layer and an outer aluminum-plastic composite tape wrapped shielding layer. The inner braided shielding layer is braided with silver-plated copper wire at a braiding density of 90%, and the outer aluminum-plastic composite tape wrapping layer has an overlap rate of 25%. The filler layer is a ceramicized silicone rubber rope with a fill factor of 95%.

[0039] The preparation method of the rubber outer sheath material is as follows:

[0040] (1) Add 8 mL of 1,4-dioxane, 0.5 g of epoxidized soybean oil, 0.34 g (2.07 mmol) of pentafluoropropionic acid and 4.1 mg of tetrabutylammonium bromide to a flask equipped with a reflux condenser. Heat to 100 °C and stir for 12 h. Dilute with water, extract with chloroform, separate, and then distill under reduced pressure and dry to obtain fluorinated soybean oil.

[0041] (2) Add 10 mL of 1,4-dioxane, 0.6 g of fluorinated soybean oil and 0.19 g of 1,3-propanesulfonic acid lactone to a flask equipped with a reflux condenser, add 0.35 mL of sodium hydroxide solution with a mass fraction of 2 g / mL, heat to 80 °C, stir and react for 6 h. After the reaction is completed, evaporate by rotary evaporation to precipitate the precipitate. After filtration, wash the precipitate with petroleum ether and dry to obtain the dispersant.

[0042] (3) Add 10 mL isopropanol, 40 mL water, 50 g zinc oxide whiskers and 0.75 g dispersant to a high-speed mixer, stir and disperse at 75 °C for 1 h at a speed of 1200 rpm, filter, wash the solid with isopropanol and water to obtain modified zinc oxide whiskers.

[0043] (4) Add 750g of EPDM rubber and 250g of fluororubber to a two-roll mill for plasticizing. Then add 300g of carbon black, 50g of modified zinc oxide whiskers, 16g of calcium hydroxide, 8g of magnesium oxide and 42g of paraffin oil for mixing. Finally add 20g of dicumyl peroxide and 22g of triallyl isocyanurate. After mixing, place the material in a flat vulcanizing machine and vulcanize it at 170℃ for 10min. Then place it in a forced-air drying oven and vulcanize it at 150℃ for 8h to obtain the rubber outer sheath material.

[0044] Example 2: A heat-resistant, interference-resistant, and tensile-resistant control cable, comprising a reinforcing core, conductor, insulation layer, shielding layer, filler layer, and rubber outer sheath. The reinforcing core is located at the center of the cable's cross-section, and the conductor is arranged in a ring-like twisted configuration around the reinforcing core. The reinforcing core is an aramid fiber bundle with a diameter of 2.0 mm. The conductor is composed of seven strands of tin-plated copper wire with a diameter of 0.3 mm, with a twist pitch 10 times the conductor's outer diameter. The insulation layer is made of polyvinyl chloride with a thickness of 0.8 mm. The shielding layer includes an inner braided shielding layer and an outer aluminum-plastic composite tape wrapped shielding layer. The inner braided shielding layer is braided with silver-plated copper wire at a braiding density of 92%, and the outer aluminum-plastic composite tape wrapping layer has an overlap rate of 25%. The filler layer is a ceramicized silicone rubber rope with a fill factor of 90%.

[0045] The preparation method of the rubber outer sheath material is as follows:

[0046] (1) Add 25 mL of 1,4-dioxane, 1.5 g of epoxidized soybean oil, 1.26 g of pentafluoropropionic acid and 15 mg of tetrabutylammonium bromide to a flask equipped with a reflux condenser. Heat to 95 °C and stir for 16 h. Add water to dilute and extract with chloroform. After separation, distill the organic layer under reduced pressure and dry to obtain fluorinated soybean oil.

[0047] (2) Add 30 mL of 1,4-dioxane, 2 g of fluorinated soybean oil, and 0.72 g of 1,3-propanesulfonic acid lactone to a flask equipped with a reflux condenser. Add 1.3 mL of sodium hydroxide solution with a mass fraction of 2 g / mL. Heat to 90 °C and stir for 7 h. After the reaction is complete, evaporate by rotary evaporation to precipitate the precipitate. After filtration, wash the precipitate with petroleum ether and dry to obtain the dispersant.

[0048] (3) Add 30 mL isopropanol, 80 mL water, 100 g zinc oxide whiskers and 2.5 g dispersant to a high-speed mixer, stir and disperse at 90 °C for 1 h at a speed of 800 rpm, filter, wash the solid with isopropanol and water to obtain modified zinc oxide whiskers.

[0049] (4) Add 900g of EPDM rubber and 100g of fluororubber to a two-roll mill for plasticizing. Then add 250g of calcium carbonate, 100g of modified zinc oxide whiskers, 6.5g of calcium hydroxide, 3.5g of magnesium oxide and 38g of paraffin oil for mixing. Finally add 23g of dicumyl peroxide and 26g of triallyl isocyanurate. After mixing, place the material in a flat vulcanizing machine and vulcanize it at 175℃ for 10min. Then place it in a forced-air drying oven and vulcanize it at 150℃ for 8h to obtain the rubber outer sheath material.

[0050] Example 3: A heat-resistant, interference-resistant, and tensile-resistant control cable, comprising a reinforcing core, conductor, insulation layer, shielding layer, filler layer, and rubber outer sheath. The reinforcing core is located at the center of the cable's cross-section, and the conductor is arranged in a ring-like twisted configuration around the reinforcing core. The reinforcing core is an aramid fiber bundle with a diameter of 1.2 mm. The conductor is composed of 19 strands of tin-plated copper wire with a diameter of 0.15 mm, with a twist pitch 15 times the conductor's outer diameter. The insulation layer is made of polyetheretherketone (PEEK) material with a thickness of 1.5 mm. The shielding layer includes an inner braided shielding layer and an outer aluminum-plastic composite tape wrapping shielding layer. The inner braided shielding layer is braided with silver-plated copper wire at a braiding density of 90%, and the outer aluminum-plastic composite tape wrapping layer has an overlap rate of 28%. The filler layer is a ceramicized silicone rubber rope with a fill factor of 90%.

[0051] The preparation method of the rubber outer sheath material is as follows:

[0052] (1) Add 40 mL of 1,4-dioxane, 3 g of epoxidized soybean oil, 1.5 g of pentafluoropropionic acid and 21 mg of tetrabutylammonium bromide to a flask equipped with a reflux condenser. Heat to 110 °C and stir for 10 h. Add water to dilute and extract with chloroform. After separation, distill the organic layer under reduced pressure and dry to obtain fluorinated soybean oil.

[0053] (2) Add 50 mL of 1,4-dioxane, 4 g of fluorinated soybean oil, and 1.04 g of 1,3-propanesulfonic acid lactone to a flask equipped with a reflux condenser. Add 1.8 mL of sodium hydroxide solution with a mass fraction of 2 g / mL. Heat to 70 °C and stir for 10 h. After the reaction is complete, evaporate by rotary evaporation to precipitate the precipitate. After filtration, wash the precipitate with petroleum ether and dry to obtain the dispersant.

[0054] (3) Add 40 mL isopropanol, 80 mL water, 100 g zinc oxide whiskers and 4 g dispersant to a high-speed mixer, stir and disperse at 80 °C for 2 h at a speed of 1200 rpm, filter, wash the solid with isopropanol and water to obtain modified zinc oxide whiskers.

[0055] (4) Add 600g of EPDM rubber and 400g of fluororubber to a two-roll mill for plasticizing. Then add 150g of silica, 200g of modified zinc oxide whiskers, 23g of calcium hydroxide, 12g of magnesium oxide and 30g of paraffin oil for mixing. Finally add 16g of dicumyl peroxide and 18g of triallyl isocyanurate. After mixing, place the material in a flat vulcanizing machine and vulcanize it at 165℃ for 15min. Then place it in a forced-air drying oven and vulcanize it at 155℃ for 5h to obtain the rubber outer sheath material.

[0056] Comparative Example 1: A cable comprising a reinforcing core, a conductor, an insulation layer, a shielding layer, a filler layer, and a rubber outer sheath. The reinforcing core is located at the center of the cable's cross-section, and the conductor is arranged in a ring-like twisted configuration around the reinforcing core. The reinforcing core is an aramid fiber bundle with a diameter of 1.5 mm. The conductor is composed of 12 strands of tinned copper wire with a diameter of 0.2 mm, with a twist pitch 10 times the conductor's outer diameter. The insulation layer is made of polyvinyl chloride with a thickness of 0.8 mm. The shielding layer includes an inner braided shielding layer and an outer aluminum-plastic composite tape wrapped shielding layer. The inner braided shielding layer is braided with silver-plated copper wire at a braiding density of 90%, and the outer aluminum-plastic composite tape wrapping layer has an overlap rate of 25%. The filler layer is a ceramicized silicone rubber rope with a fill factor of 95%.

[0057] The preparation method of the rubber outer sheath material is as follows:

[0058] (1) Add 750g of EPDM rubber and 250g of fluororubber to a two-roll mill for plasticizing. Then add 300g of carbon black, 50g of zinc oxide whiskers, 16g of calcium hydroxide, 8g of magnesium oxide and 42g of paraffin oil for mixing. Finally add 20g of dicumyl peroxide and 22g of triallyl isocyanurate. After mixing, place the material in a flat vulcanizing machine and vulcanize it at 170℃ for 10min. Then place it in a forced-air drying oven and vulcanize it at 150℃ for 8h to obtain the rubber outer sheath material.

[0059] Comparative Example 2: A cable comprising a reinforcing core, a conductor, an insulation layer, a shielding layer, a filler layer, and a rubber outer sheath. The reinforcing core is located at the center of the cable's cross-section, and the conductor is arranged in a ring-like twisted configuration around the reinforcing core. The reinforcing core is an aramid fiber bundle with a diameter of 1.5 mm. The conductor is composed of 12 strands of tinned copper wire with a diameter of 0.2 mm, with a twist pitch 10 times the conductor's outer diameter. The insulation layer is made of polyvinyl chloride with a thickness of 0.8 mm. The shielding layer includes an inner braided shielding layer and an outer aluminum-plastic composite tape wrapped shielding layer. The inner braided shielding layer is braided with silver-plated copper wire at a braiding density of 90%, and the outer aluminum-plastic composite tape wrapping layer has an overlap rate of 25%. The filler layer is a ceramicized silicone rubber rope with a fill factor of 95%.

[0060] The preparation method of the rubber outer sheath material is as follows:

[0061] (1) Add 10 mL of isopropanol, 40 mL of water, 50 g of zinc oxide whiskers and 0.75 g of sodium dodecyl sulfonate to a high-speed mixer, stir and disperse at 75 °C for 1 h at a speed of 1200 rpm, filter, wash the solid with isopropanol and water to obtain modified zinc oxide whiskers.

[0062] (2) Add 750g of EPDM rubber and 250g of fluororubber to a two-roll mill for plasticizing. Then add 300g of carbon black, 50g of modified zinc oxide whiskers, 16g of calcium hydroxide, 8g of magnesium oxide and 42g of paraffin oil for mixing. Finally add 20g of dicumyl peroxide and 22g of triallyl isocyanurate. After mixing, place the material in a flat vulcanizing machine and vulcanize it at 170℃ for 10min. Then place it in a forced-air drying oven and vulcanize it at 150℃ for 8h to obtain the rubber outer sheath material.

[0063] Comparative Example 3: A heat-resistant, interference-resistant, and tensile-resistant control cable, comprising a reinforcing core, conductor, insulation layer, shielding layer, filler layer, and rubber outer sheath. The reinforcing core is located at the center of the cable's cross-section, and the conductor is arranged in a ring-like twisted configuration around the reinforcing core. The reinforcing core is an aramid fiber bundle with a diameter of 1.5 mm. The conductor is composed of 12 strands of tin-plated copper wire with a diameter of 0.2 mm, with a twist pitch 10 times the conductor's outer diameter. The insulation layer is made of polyvinyl chloride with a thickness of 0.8 mm. The shielding layer includes an inner braided shielding layer and an outer aluminum-plastic composite tape wrapped shielding layer. The inner braided shielding layer is braided with silver-plated copper wire at a braiding density of 90%, and the outer aluminum-plastic composite tape wrapping layer has an overlap rate of 25%. The filler layer is a ceramicized silicone rubber rope with a fill factor of 95%.

[0064] The preparation method of the rubber outer sheath material is as follows:

[0065] (1) Add 10 mL isopropanol, 40 mL water, 50 g zinc oxide whiskers and 0.75 g fluorinated soybean oil (prepared from Example 1) to a high-speed mixer, stir and disperse at 75 °C for 1 h at a speed of 1200 rpm, filter, wash the solid with isopropanol and water to obtain modified zinc oxide whiskers.

[0066] (2) Add 750g of EPDM rubber and 250g of fluororubber to a two-roll mill for plasticizing. Then add 300g of carbon black, 50g of modified zinc oxide whiskers, 16g of calcium hydroxide, 8g of magnesium oxide and 42g of paraffin oil for mixing. Finally add 20g of dicumyl peroxide and 22g of triallyl isocyanurate. After mixing, place the material in a flat vulcanizing machine and vulcanize it at 170℃ for 10min. Then place it in a forced-air drying oven and vulcanize it at 150℃ for 8h to obtain the rubber outer sheath material.

[0067] Comparative Example 4: A heat-resistant, interference-resistant, and tensile-resistant control cable, comprising a reinforcing core, conductor, insulation layer, shielding layer, filler layer, and rubber outer sheath. The reinforcing core is located at the center of the cable's cross-section, and the conductor is arranged in a ring-like twisted configuration around the reinforcing core. The reinforcing core is an aramid fiber bundle with a diameter of 1.5 mm. The conductor is composed of 12 strands of tin-plated copper wire with a diameter of 0.2 mm, with a twist pitch 10 times the conductor's outer diameter. The insulation layer is made of polyvinyl chloride with a thickness of 0.8 mm. The shielding layer includes an inner braided shielding layer and an outer aluminum-plastic composite tape wrapped shielding layer. The inner braided shielding layer is braided with silver-plated copper wire at a braiding density of 90%, and the outer aluminum-plastic composite tape wrapping layer has an overlap rate of 25%. The filler layer is a ceramicized silicone rubber rope with a fill factor of 95%.

[0068] The preparation method of the rubber outer sheath material is as follows:

[0069] (1) Add 8 mL of 1,4-dioxane, 0.5 g of epoxidized soybean oil, 0.18 g (2.07 mmol) of n-propionic acid and 4.1 mg of tetrabutylammonium bromide to a flask equipped with a reflux condenser. Heat to 100 °C and stir for 12 h. Dilute with water, extract with chloroform, separate, and then distill under reduced pressure and dry to obtain propyl soybean oil.

[0070] (2) Add 10 mL of 1,4-dioxane, 0.6 g of propyl soybean oil and 0.19 g of 1,3-propanesulfonic acid lactone to a flask equipped with a reflux condenser, add 0.35 mL of sodium hydroxide solution with a mass fraction of 2 g / mL, heat to 80 °C, stir and react for 6 h. After the reaction is completed, evaporate by rotary evaporation to precipitate the precipitate. After filtration, wash the precipitate with petroleum ether and dry to obtain the dispersant.

[0071] (3) Add 10 mL isopropanol, 40 mL water, 50 g zinc oxide whiskers and 0.75 g dispersant to a high-speed mixer, stir and disperse at 75 °C for 1 h at a speed of 1200 rpm, filter, wash the solid with isopropanol and water to obtain modified zinc oxide whiskers.

[0072] (4) Add 750g of EPDM rubber and 250g of fluororubber to a two-roll mill for plasticizing. Then add 300g of carbon black, 50g of modified zinc oxide whiskers, 16g of calcium hydroxide, 8g of magnesium oxide and 42g of paraffin oil for mixing. Finally add 20g of dicumyl peroxide and 22g of triallyl isocyanurate. After mixing, place the material in a flat vulcanizing machine and vulcanize it at 170℃ for 10min. Then place it in a forced-air drying oven and vulcanize it at 150℃ for 8h to obtain the rubber outer sheath material.

[0073] The tensile properties of the rubber outer sheath material were tested according to standard GB / T 528-2009. The tear strength was tested according to standard GB / T 529-2008.

[0074] The rubber outer sheath material was placed in a thermogravimetric analyzer, and its thermal properties were tested in a nitrogen atmosphere at a heating rate of 5℃ / min.

[0075] Table 1 Performance Tests

[0076] Tensile strength (MPa) Elongation at break (%) Tear strength (kN / m) <![CDATA[T 5% (℃)]]> <![CDATA[T max (℃)]]> Example 1 9.28 275.7 24.7 384.5 447.0 Example 2 11.36 254.1 27.3 378.4 441.9 Example 3 8.30 326.9 22.5 389.6 457.2 Comparative Example 1 7.65 232.6 19.6 381.4 443.3 Comparative Example 2 8.31 245.2 21.9 383.1 445.7 Comparative Example 3 7.68 233.4 19.8 382.0 443.5 Comparative Example 4 8.73 258.9 23.2 383.9 446.3

[0077] In Comparative Example 1, the rubber outer sheath material used EPDM rubber and fluororubber as blended rubbers. The added zinc oxide whiskers had poor compatibility with EPDM rubber and fluororubber, making it difficult to disperse evenly in the rubber matrix. This resulted in a weak reinforcing effect of the zinc oxide whiskers, leading to lower tensile strength and tear strength in the rubber outer sheath material, and a lower initial thermal decomposition temperature T. 5% and the temperature T of the maximum mass loss rate max The strength is low, and the heat resistance is poor. The dispersant in Example 1 contains multiple sulfonate groups, which can adsorb onto the surface of zinc oxide whiskers, modifying the surface of the zinc oxide whiskers and acting as a steric hindrance, which helps reduce the aggregation of zinc oxide whiskers. At the same time, the dispersant contains long carbon chains, which can improve the compatibility of zinc oxide whiskers with EPDM rubber. Furthermore, the dispersant contains multiple fluorine-containing groups, which can improve the compatibility of zinc oxide whiskers with fluororubber, allowing the zinc oxide whiskers to be uniformly dispersed in the rubber matrix, resulting in a better reinforcing effect. The tensile strength and tear strength of the rubber outer sheath material are significantly higher than those of Comparative Example 1. 5% and T max There is also a significant improvement. In Examples 2 and 3, different amounts of EPDM rubber, fluororubber and modified zinc oxide whiskers were added, and the resulting rubber outer sheath materials also have good tensile properties, tear strength and heat resistance.

[0078] Comparative Example 2 uses conventional sodium dodecyl sulfonate as a dispersant, which does not contain fluorine-containing groups, making it difficult to improve the compatibility between zinc oxide whiskers and fluororubber. This results in the tensile strength and tear strength of the rubber outer sheath material being lower than those in Example 1.

[0079] Comparative Example 3: Fluorinated soybean oil does not contain sulfonate groups, making it difficult to adsorb onto the surface of zinc oxide whiskers. It cannot be modified onto the surface of zinc oxide whiskers. After washing, the zinc oxide whiskers contain almost no surface dispersant, resulting in poor compatibility between zinc oxide whiskers and EPDM rubber and fluororubber. It is difficult to disperse evenly in the rubber matrix, resulting in lower tensile strength and tear strength of the rubber outer sheath material than in Example 1.

[0080] The dispersant in Comparative Example 4 does not contain fluorine-containing groups, making it difficult to improve the compatibility between zinc oxide whiskers and fluororubber, resulting in lower tensile strength and tear strength of the rubber outer sheath material compared to Example 1.

[0081] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A heat resistant, tamper resistant, pull resistant control cable, characterized in that, The heat-resistant, interference-resistant, and tensile-resistant control cable consists of a reinforced core, conductor, insulation layer, shielding layer, filling layer, and rubber outer sheath. The rubber outer sheath material comprises 60-90 parts by weight of EPDM rubber, 10-40 parts by weight of fluororubber, 15-30 parts by weight of reinforcing agent, 5-20 parts by weight of modified zinc oxide whiskers, 3-4.2 parts by weight of lubricant, 1.6-2.3 parts by weight of vulcanizing agent, 1.8-2.6 parts by weight of crosslinking agent, and 1-3.5 parts by weight of acid absorbent. The modified zinc oxide whiskers are prepared according to the following method: (1) Add 1,4-dioxane, epoxidized soybean oil, pentafluoropropionic acid and tetrabutylammonium bromide to a flask, react, extract and separate to obtain fluorinated soybean oil; (2) Add 1,4-dioxane, fluorinated soybean oil, and 1,3-propanesulfonate lactone to a flask, add sodium hydroxide solution dropwise, and carry out the reaction. After the reaction is completed, evaporate by rotary evaporation, filter, wash the precipitate, and dry to obtain the dispersant. (3) Add isopropanol, water, zinc oxide whiskers and dispersant to a high-speed mixer, disperse, filter and wash the solid to obtain modified zinc oxide whiskers.

2. The heat-resistant, tamper-resistant, pull-resistant control cable of claim 1, wherein, The reinforcing core is located at the center of the cable's cross-section, and the conductor is arranged in a ring-shaped twist around the reinforcing core. The reinforcing core is an aramid fiber bundle with a diameter of 1.2-2.0 mm. The conductor is made of 7-19 strands of tinned copper wire with a diameter of 0.15-0.3 mm, and the twist pitch is 10-15 times the outer diameter of the conductor.

3. The heat-resistant, tamper-resistant, pull-resistant control cable of claim 1, wherein, The insulating layer is made of polyvinyl chloride or polyetheretherketone and has a thickness of 0.8-1.5 mm.

4. The heat-resistant, tamper-resistant, pull-resistant control cable of claim 1, wherein, The shielding layer includes an inner braided shielding layer and an outer aluminum-plastic composite tape wrapping shielding layer. The inner braided shielding layer is woven with silver-plated copper wire with a braiding density of 90-92%, and the outer aluminum-plastic composite tape wrapping has an overlap rate of 25-28%.

5. The heat-resistant, tamper-resistant, pull-resistant control cable of claim 1, wherein, The filling layer is a ceramicized silicone rubber rope with a filling coefficient of 90-95%.

6. The heat-resistant, interference-resistant, and tensile-resistant control cable according to claim 1, characterized in that, The reinforcing agent is one or more of carbon black, silica, and calcium carbonate; the acid absorber is one or more of calcium hydroxide and magnesium oxide; the lubricant is paraffin oil; the vulcanizing agent is dicumyl peroxide; and the crosslinking agent is triallyl isocyanurate.

7. The heat-resistant, interference-resistant, and tensile-resistant control cable according to claim 1, characterized in that, In step (1), the amount of epoxidized soybean oil is 100 parts by weight, pentafluoropropionic acid is 50-84 parts by weight, tetrabutylammonium bromide is 0.7-1 parts by weight, and the reaction is carried out at 95-110℃ for 10-16 hours.

8. The heat-resistant, interference-resistant, and tensile-resistant control cable according to claim 1, characterized in that, The amount of fluorinated soybean oil used in (2) is 100 parts by weight, and the amount of 1,3-propanesulfonate lactone is 26-36 parts by weight. The reaction is carried out at 70-90℃ for 6-10 hours.

9. The heat-resistant, interference-resistant, and tensile-resistant control cable according to claim 1, characterized in that, The amount of zinc oxide whiskers used in (3) is 100 parts by weight, the amount of dispersant is 1.5-4 parts by weight, the temperature inside the high-speed mixer is 75-90℃, the rotation speed is 800-1200rpm, and the dispersion time is 1-2h.

10. The heat-resistant, interference-resistant, and tensile-resistant control cable according to claim 1, characterized in that, The preparation method of the rubber outer sheath material is as follows: EPDM rubber and fluororubber are added to an open mill for plasticizing, then reinforcing agent, modified zinc oxide whiskers, acid absorber, and lubricant are added and mixed, and finally vulcanizing agent and crosslinking agent are added. After mixing, the material is placed in a flat vulcanizing machine and vulcanized for 10-15 minutes at 165-175℃. Then it is placed in a forced-air drying oven and vulcanized for 5-8 hours at 150-155℃ to obtain the rubber outer sheath material.