High-tear-resistance oil-resistant double-crosslinking low-smoke halogen-free flame-retardant cable sheath material and production process thereof

Abstract

The invention relates to the technical field of cable materials, in particular to a high-tear-resistance oil-resistant double-crosslinking low-smoke halogen-free flame-retardant cable sheathing material and a production process thereof. The modified silicon dioxide hybrid graphene material is obtained by adding a silicon dioxide hybrid graphene material, triethylamine, diethyldichlorophosphorus and eugenol. The preparation method comprises the following steps: adding methyl methacrylate, methacrylamide, phosphoric acid acrylate, phosphazene acrylate and ethidene diamine to obtain aminated polyacrylate microspheres; the flame-retardant modified silicon dioxide hybrid graphene material is obtained by adding the modified silicon dioxide hybrid graphene material, triethylamine, modified sepiolite, aminated polyacrylate microspheres and deionized water. And mixing natural rubber, nitrile rubber, the flame-retardant modified silicon dioxide hybrid graphene material and an additive, and mixing to obtain the cable sheath material. The cable sheathing material prepared by the invention has good flame retardance and mechanical properties, so that the cable sheathing material has a wide application prospect in the technical field of cable materials.

Description

Technical Field

[0001] The invention relates to the technical field of cable materials, and in particular to a highly tear-resistant and oil-resistant double-crosslinked low-smoke and halogen-free flame-retardant cable sheathing material and a production process. Background Art

[0002] In modern society, cables are important communication networks in cities. They silently but crucially support the normal operation of various fields and have inestimable value. From the perspective of energy transmission, cables are the key carriers of power transmission. Whether it is a large power plant sending electricity to every corner of the city or power distribution within a factory, cables play a core role. It transmits electric energy efficiently and stably, reduces energy loss, and ensures the continuous progress of industrial production and the normal electricity consumption of residents. In the field of new energy, such as solar and wind power plants, cables transmit clean energy to the power grid, promoting the green transformation of the energy structure. As the raw material of the protective jacket of the cable, the cable sheath plays an indispensable role. It can protect the conductor inside the cable from the influence of the external environment, such as mechanical damage, chemical corrosion, moisture intrusion, etc. High-quality cable sheath can extend the service life of the cable and reduce maintenance costs. In some harsh industrial environments or outdoor environments, the protective performance of the cable sheath is directly related to whether the cable can work normally. At the same time, the cable sheath can also play an insulating role, prevent current leakage, and ensure the safety of electricity use.

[0003] Cables are widely distributed in construction, transportation, industry and other places. Once a fire occurs, ordinary cables are easy to burn and release a lot of toxic smoke, which will not only accelerate the spread of the fire, but also pose a serious threat to the life safety of personnel. However, cables with good flame retardant properties can effectively prevent the spread of fire when encountering a fire source, reducing the degree of fire damage; for example, in crowded places such as large shopping malls and hospitals, flame retardant cables can buy precious time for personnel evacuation and fire rescue, reducing casualties and property losses. In addition, from the perspective of mechanical properties, during the installation process, the cable will be subjected to external forces such as pulling, bending, and squeezing. If the mechanical properties are not good, it is easy to break or break, affecting the normal use of the cable. In some industrial occasions, cables need to work in harsh mechanical environments, such as mines and construction sites. Cables with high tear resistance can withstand greater external forces, ensure the integrity and stability of the cable, and reduce failures and maintenance costs caused by mechanical damage.

[0004] In order to overcome the defects of the prior art, the present invention provides a highly tear-resistant and oil-resistant double-cross-linked low-smoke and halogen-free flame-retardant cable sheathing material and a production process. Summary of the invention

[0005] The object of the present invention is to provide a highly tear-resistant and oil-resistant double-crosslinked low-smoke and halogen-free flame-retardant cable sheath material and a production process to solve the problems raised in the prior art.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A production process of a high tear-resistant, oil-resistant, double-crosslinked, low-smoke, halogen-free flame-retardant cable compound, comprising the following steps:

[0008] Step 1: Add the silica hybrid graphene material to tetrahydrofuran, stir well, ultrasonically disperse for 3-4 h, then add triethylamine, let stand at 0-3 °C for 1-2 h, and then slowly add the diethyl dichlorophosphine solution and the eugenol solution, react in a nitrogen environment for 2-3 h, then raise the temperature to 60-65 °C and reflux for 3-4 h. After the reaction is completed, wash and vacuum dry to obtain the modified silica hybrid graphene material;

[0009] Step 2: Add methyl methacrylate, methacrylamide, phosphoacrylate, and phosphazene acrylate to deionized water, then add polyvinylpyrrolidone, raise the temperature to 70-80 °C in a nitrogen environment, and then add 2,2'-azobis(2-methylpropionamidine) dihydrochloride and continue to react for 6-8 h. After the reaction is completed, cool, centrifuge, wash, dry, and grind to obtain polyacrylate microspheres; Add the polyacrylate microspheres to deionized water, ultrasonically disperse for 20-30 min, then raise the temperature to 70-80 °C, and then add sodium hydroxide and ethylenediamine and react for 10-12 h. After the reaction is completed, cool, filter, wash, dry, and grind to obtain aminated polyacrylate microspheres;

[0010] Step 3: Add the modified silica hybrid graphene material and triethylamine to tetrahydrofuran, stir well, and then sequentially add the modified sepiolite solution and the aminated polyacrylate microsphere solution. After the addition is completed, reflux at 60-65 °C for 3-4 h, then add deionized water and continue to react for 3-4 h, and then cool to 20-25 °C and continue to react for 10-12 h. After the reaction is completed, centrifuge, wash, and vacuum dry to obtain the flame-retardant modified silica hybrid graphene material;

[0011] Step 4: Mix natural rubber, nitrile rubber, the flame-retardant modified silica hybrid graphene material, vulcanizing agent, plasticizer, antioxidant, and mica powder, and knead at 150-170 °C for 40-50 min to obtain the cable compound.

[0012] Preferably, in Step 1, dissolve diethyl dichlorophosphine in tetrahydrofuran to obtain the diethyl dichlorophosphine solution; dissolve eugenol in tetrahydrofuran to obtain the eugenol solution; the reaction mass ratio of the silica hybrid graphene material, diethyl dichlorophosphine, eugenol, and triethylamine is 0.1:(0.4-0.45):(0.2-0.25):1.

[0013] Preferably, the preparation process of the silica hybrid graphene material is as follows: Graphene oxide and nano-silica are respectively added to anhydrous ethanol, and then the two solutions are mixed and mechanically stirred for 30 - 40 min. Then, dicyclohexylcarbodiimide and 4-dimethylaminopyridine are added, and the mixture is continuously stirred and reacted for 8 - 10 h. After the reaction, it is centrifuged, washed, dried, and ground to obtain the silica hybrid graphene material; the reaction mass ratio of graphene oxide to nano-silica is (1.0 - 1.2):3.

[0014] Preferably, in step two, the reaction molar ratio of methyl methacrylate, methacrylamide, phosphoric acid acrylate, and phosphazene acrylate is (2 - 3):1:2:(2 - 3); the reaction mass ratio of polyacrylate microspheres, sodium hydroxide, and ethylenediamine is 5:0.9:(18 - 20).

[0015] Preferably, the preparation process of phosphoric acid acrylate is as follows: Hydroxyethyl methacrylate and diphenyl phosphorochloridate are respectively dissolved in tetrahydrofuran to obtain a hydroxyethyl methacrylate solution and a diphenyl phosphorochloridate solution; triethylamine is added to the hydroxyethyl methacrylate solution, and after sufficient stirring, the diphenyl phosphorochloridate solution is added dropwise, and the mixture is refluxed and reacted at 60 - 65 °C for 20 - 25 h. After the reaction, it is filtered, rotary evaporated, extracted, and dried to obtain phosphoric acid acrylate;

[0016] The preparation process of phosphazene acrylate is as follows: Hydroxyethyl methacrylate and hexachlorocyclotriphosphazene are respectively dissolved in tetrahydrofuran to obtain a hydroxyethyl methacrylate solution and a hexachlorocyclotriphosphazene solution; triethylamine is added to the hydroxyethyl methacrylate solution, and after sufficient stirring, the hexachlorocyclotriphosphazene solution is added dropwise, and the mixture is refluxed and reacted at 60 - 65 °C for 20 - 25 h. After the reaction, it is filtered, rotary evaporated, extracted, and dried to obtain phosphazene acrylate.

[0017] Preferably, the reaction mass ratio of hydroxyethyl methacrylate, diphenyl phosphorochloridate, and triethylamine is (18 - 20):32:19; the reaction mass ratio of hydroxyethyl methacrylate, hexachlorocyclotriphosphazene, and triethylamine is (18 - 20):10:19.

[0018] Preferably, in step three, the modified sepiolite is dissolved in tetrahydrofuran to obtain a modified sepiolite solution; the aminated polyacrylate microspheres are dissolved in tetrahydrofuran to obtain an aminated polyacrylate microsphere solution; the reaction mass ratio of the modified silica hybrid graphene material, triethylamine, modified sepiolite, aminated polyacrylate microspheres, and deionized water is 3:13:(2 - 2.5):(3 - 3.5):0.5.

[0019] Preferably, the preparation process of the modified sepiolite is as follows: mix sepiolite, absolute ethanol and γ-aminopropyltriethoxysilane, stir well for 20 - 25 min, and after stirring, wash and dry to obtain the modified sepiolite; the reaction mass ratio of sepiolite to γ-aminopropyltriethoxysilane is (15 - 20):1.

[0020] Preferably, in step four, the component contents of the cable sheath are as follows: by mass, 70 - 80 parts of natural rubber, 20 - 30 parts of nitrile rubber, 18 - 25 parts of flame-retardant modified silica hybrid graphene material, 3 - 5 parts of vulcanizing agent, 5 - 10 parts of plasticizer, 2 - 3 parts of anti-aging agent, and 10 - 15 parts of mica powder; the vulcanizing agent is sulfur; the plasticizer is dioctyl phthalate; the anti-aging agent is 2,6-di-tert-butyl-4-methylphenol.

[0021] The beneficial effects of the present invention:

[0022] The characteristics of the present invention are as follows. In step one, by adding graphene oxide, nano-silica, and a catalyst, a silica hybrid graphene material is obtained. Then, by adding the silica hybrid graphene material, triethylamine, diethyldichlorophosphine, and eugenol, a modified silica hybrid graphene material is obtained. In this step, first, nano-silica is assembled in the graphene structure through an esterification reaction. On the one hand, this can improve the agglomeration phenomenon of the graphene structure. On the other hand, by compounding graphene with silica, their respective performance advantages can be better exerted. When stressed, they can cooperate with each other to produce a synergistic effect and jointly resist external forces. Specifically, when the material is subjected to a tearing force, the flexibility of graphene can cause the material to deform to a certain extent without breaking, while the rigidity of nano-silica can prevent the further expansion of cracks. This synergistic effect makes the material consume more energy during the tearing process, thus significantly improving the tear resistance of the material. Then, by adding diethyldichlorophosphine, eugenol and the silica hybrid graphene material to undergo a substitution reaction, adding diethyldichlorophosphine can improve the flame retardancy of the material, and adding eugenol can introduce C=C.

[0023] The characteristics of the present invention are as follows. In step two, by adding methyl methacrylate, methacrylamide, phosphoric acid acrylate, phosphazene acrylate, a dispersant, and an initiator, polyacrylate microspheres are obtained. By setting the reaction molar ratio of methyl methacrylate, methacrylamide, phosphoric acid acrylate, and phosphazene acrylate to (2 - 3):1:2:(2 - 3) in this step, polyacrylate microspheres with good flame retardancy are obtained; and by introducing methyl methacrylate in this step, after the ester group is hydrolyzed, the next step of amination modification can be carried out to obtain aminated polyacrylate microspheres.

[0024] The characteristics of the present invention lie in that in step three, by adding a modified silica hybrid graphene material, triethylamine, modified sepiolite, aminated polyacrylate microspheres, and deionized water, a flame-retardant modified silica hybrid graphene material is obtained. In this step, the epoxy groups of the modified silica hybrid graphene material react with the amino groups of the modified sepiolite and the amino groups of the aminated polyacrylate microspheres to obtain the flame-retardant modified silica hybrid graphene material. On the one hand, sepiolite has a unique fibrous structure. When these fibrous substances are uniformly dispersed in the system, they can interpenetrate between the graphene sheets like a fence. When there is a tendency for the graphene sheets to approach each other and agglomerate, the sepiolite fibers will play a physical barrier role to prevent the direct contact and stacking of the graphene sheets, thereby reducing the occurrence of agglomeration. The microsphere structure of the aminated polyacrylate microspheres will collide and rub with the graphene sheets, and this mechanical action can break up the already formed small aggregates, making the graphene more dispersed, thus improving the agglomeration phenomenon of graphene.

[0025] On the other hand, sepiolite has a large specific surface area and a rich pore structure, which can adsorb some combustible gases and free radicals generated during the combustion process, thereby inhibiting the progress of combustion. Therefore, after blending and reacting the modified silica hybrid graphene material with good flame-retardant performance, modified sepiolite, and aminated polyacrylate microspheres, through synergistic flame retardancy, the obtained flame-retardant modified silica hybrid graphene material has excellent flame-retardant performance.

[0026] In step four, natural rubber, nitrile rubber, the flame-retardant modified silica hybrid graphene material, a vulcanizing agent, a plasticizer, an antioxidant, and mica powder are mixed and kneaded to obtain a cable compound. The double bonds in natural rubber and nitrile rubber and the C=C double bonds introduced by adding eugenol in the flame-retardant modified silica hybrid graphene material can undergo vulcanization crosslinking under the action of the vulcanizing agent to produce a double crosslinked network. In summary, the cable compound prepared by the present invention has good flame retardancy and mechanical properties, and thus has broad application prospects in the field of cable material technology. Specific embodiments

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0028] Source of raw materials:

[0029] Graphene oxide, provided by Changzhou Yaobang Friction Materials Factory, with a particle size of 2 nm; nano-silica, provided by Baoyi Mineral Products Processing Factory in Lingshou County, with a particle size of 10 μm; polyvinylpyrrolidone, provided by Jinan Weizhen Chemical Co., Ltd., with a molecular weight of 8000; 2,2'-azobis(2-methylpropionamidine) dihydrochloride, provided by Tianjin Damao Chemical Reagent Factory, with an analytical purity specification; sepiolite, provided by Hongyang Sepiolite Co., Ltd. in Neixiang County, with a 100-mesh specification; natural rubber is natural rubber latex (60 wt%) provided by Zhongbing Industry Co., Ltd. in Zhongshan City, with an industrial-grade specification; nitrile rubber, provided by Hangzhou Yusheng Environmental Technology Co., Ltd., with a content of 95%; mica powder, provided by Shijiazhuang Mayue Building Materials Co., Ltd., with a 200-mesh specification; by mass fraction, one part is 1 g.

[0030] Example 1: Step 1: Add graphene oxide and nano-silica to anhydrous ethanol respectively, then mix the two solutions, mechanically stir for 40 min, then add dicyclohexylcarbodiimide and 4-dimethylaminopyridine, and continue to stir and react for 10 h. After the reaction is completed, centrifuge, wash, dry, and grind to obtain silica hybrid graphene material; the reaction mass ratio of graphene oxide to nano-silica is 1.1:3;

[0031] Add the silica hybrid graphene material to tetrahydrofuran, fully stir and then ultrasonically disperse for 4 h, then dropwise add triethylamine, let it stand at 3 °C for 2 h, then slowly dropwise add diethyl dichlorophosphate solution and eugenol solution, react for 3 h in a nitrogen environment, then raise the temperature to 65 °C and reflux for 4 h. After the reaction is completed, wash and vacuum dry to obtain modified silica hybrid graphene material; dissolve diethyl dichlorophosphate in tetrahydrofuran to obtain diethyl dichlorophosphate solution; dissolve eugenol in tetrahydrofuran to obtain eugenol solution; the reaction mass ratio of silica hybrid graphene material, diethyl dichlorophosphate, eugenol, and triethylamine is 0.1:0.42:0.23:1;

[0032] Step 2: Dissolve 2-hydroxyethyl methacrylate and diphenyl chlorophosphate in tetrahydrofuran respectively to obtain 2-hydroxyethyl methacrylate solution and diphenyl chlorophosphate solution; add triethylamine to the 2-hydroxyethyl methacrylate solution, fully stir and then dropwise add the diphenyl chlorophosphate solution, reflux and react at 65 °C for 25 h. After the reaction is completed, filter, rotary evaporate, extract, and dry to obtain phosphoacrylate; the reaction mass ratio of 2-hydroxyethyl methacrylate, diphenyl chlorophosphate, and triethylamine is 19:32:19;

[0033] Dissolve hydroxyethyl methacrylate and hexachlorocyclotriphosphazene in tetrahydrofuran respectively to obtain a hydroxyethyl methacrylate solution and a hexachlorocyclotriphosphazene solution; add triethylamine to the hydroxyethyl methacrylate solution, stir well and then dropwise add the hexachlorocyclotriphosphazene solution, reflux and react at 65 °C for 25 h. After the reaction is completed, filter, rotary evaporate, extract and dry to obtain phosphazene acrylate; the reaction mass ratio of hydroxyethyl methacrylate, hexachlorocyclotriphosphazene and triethylamine is 19:10:19;

[0034] Add methyl methacrylate, methacrylamide, phosphoric acid acrylate and phosphazene acrylate to deionized water, then add polyvinylpyrrolidone, heat up to 80 °C in a nitrogen environment, and then add 2,2'-azobis(2-methylpropionamidine) dihydrochloride and continue to react for 8 h. After the reaction is completed, cool, centrifuge, wash, dry and grind to obtain polyacrylate microspheres; add the polyacrylate microspheres to deionized water, ultrasonically disperse for 30 min and then heat up to 80 °C, and then add sodium hydroxide and ethylenediamine and react for 12 h. After the reaction is completed, cool, filter, wash, dry and grind to obtain aminated polyacrylate microspheres; the reaction molar ratio of methyl methacrylate, methacrylamide, phosphoric acid acrylate and phosphazene acrylate is 2.5:1:2:2.5; the reaction mass ratio of polyacrylate microspheres, sodium hydroxide and ethylenediamine is 5:0.9:19;

[0035] Step three: Mix sepiolite, anhydrous ethanol and γ-aminopropyltriethoxysilane, stir well for 25 min, and after stirring, wash and dry to obtain modified sepiolite; the reaction mass ratio of sepiolite and γ-aminopropyltriethoxysilane is 17:1;

[0036] Add the modified silica hybrid graphene material and triethylamine to tetrahydrofuran, stir well and then successively dropwise add the modified sepiolite solution and the aminated polyacrylate microsphere solution. After the addition is completed, reflux and react at 65 °C for 4 h, then dropwise add deionized water and continue to react for 4 h, and then cool down to 25 °C and continue to react for 12 h. After the reaction is completed, centrifuge, wash and vacuum dry to obtain a flame-retardant modified silica hybrid graphene material; dissolve the modified sepiolite in tetrahydrofuran to obtain a modified sepiolite solution; dissolve the aminated polyacrylate microspheres in tetrahydrofuran to obtain an aminated polyacrylate microsphere solution; the reaction mass ratio of the modified silica hybrid graphene material, triethylamine, modified sepiolite, aminated polyacrylate microspheres and deionized water is 3:13:2.2:3.3:0.5;

[0037] Step four: Mix 80 g of natural rubber, 30 g of nitrile rubber, 25 g of the flame-retardant modified silica hybrid graphene material, 5 g of sulfur, 10 g of dioctyl phthalate, 3 g of 2,6-di-tert-butyl-4-methylphenol and 15 g of mica powder, and mix at 170 °C for 50 min to obtain cable compound.

[0038] Example 2: Step 1: Graphene oxide and nano-silica are respectively added into absolute ethanol, and then the two solutions are mixed and mechanically stirred for 35 min. Then dicyclohexylcarbodiimide and 4-dimethylaminopyridine are added, and stirring reaction is continued for 9 h. After the reaction ends, centrifugation, washing, drying and grinding are carried out to obtain silica hybrid graphene material; the reaction mass ratio of graphene oxide to nano-silica is 1.1:3;

[0039] The silica hybrid graphene material is added into tetrahydrofuran, and after sufficient stirring, it is ultrasonically dispersed for 3.5 h. Then triethylamine is added dropwise, and it is left standing at 2°C for 1.5 h. Then a solution of diethyl dichlorophosphate and a solution of eugenol are slowly added dropwise, and the reaction is carried out for 2.5 h under a nitrogen atmosphere. Then the temperature is raised to 62°C for reflux reaction for 3.5 h. After the reaction ends, washing and vacuum drying are carried out to obtain modified silica hybrid graphene material; diethyl dichlorophosphate is dissolved in tetrahydrofuran to obtain a diethyl dichlorophosphate solution; eugenol is dissolved in tetrahydrofuran to obtain an eugenol solution; the reaction mass ratio of silica hybrid graphene material, diethyl dichlorophosphate, eugenol and triethylamine is 0.1:0.42:0.23:1;

[0040] Step 2: Hydroxyethyl methacrylate and diphenyl chlorophosphate are respectively dissolved in tetrahydrofuran to obtain a hydroxyethyl methacrylate solution and a diphenyl chlorophosphate solution; triethylamine is added to the hydroxyethyl methacrylate solution, and after sufficient stirring, the diphenyl chlorophosphate solution is added dropwise, and the reaction is carried out at 62°C for reflux for 22 h. After the reaction ends, filtration, rotary evaporation, extraction and drying are carried out to obtain phosphoacrylate; the reaction mass ratio of hydroxyethyl methacrylate, diphenyl chlorophosphate and triethylamine is 19:32:19;

[0041] Hydroxyethyl methacrylate and hexachlorocyclotriphosphazene are respectively dissolved in tetrahydrofuran to obtain a hydroxyethyl methacrylate solution and a hexachlorocyclotriphosphazene solution; triethylamine is added to the hydroxyethyl methacrylate solution, and after sufficient stirring, the hexachlorocyclotriphosphazene solution is added dropwise, and the reaction is carried out at 63°C for reflux for 22 h. After the reaction ends, filtration, rotary evaporation, extraction and drying are carried out to obtain phosphazene acrylate; the reaction mass ratio of hydroxyethyl methacrylate, hexachlorocyclotriphosphazene and triethylamine is 19:10:19;

[0042] Methyl methacrylate, methacrylamide, phosphoric acid acrylate, and phosphazene acrylate were added to deionized water, and then polyvinylpyrrolidone was added. The temperature was raised to 75 °C under a nitrogen atmosphere, and then 2,2'-azobis(2-methylpropionamidine) dihydrochloride was added and the reaction continued for 7 h. After the reaction ended, it was cooled, centrifuged, washed, dried, and ground to obtain polyacrylate microspheres; the polyacrylate microspheres were added to deionized water, ultrasonically dispersed for 25 min, and then the temperature was raised to 75 °C. Sodium hydroxide and ethylenediamine were added and the reaction continued for 11 h. After the reaction ended, it was cooled, filtered by suction, washed, dried, and ground to obtain aminated polyacrylate microspheres; the reaction molar ratio of methyl methacrylate, methacrylamide, phosphoric acid acrylate, and phosphazene acrylate was 2.5:1:2:2.5; the reaction mass ratio of polyacrylate microspheres, sodium hydroxide, and ethylenediamine was 5:0.9:19;

[0043] Step 3: Mix sepiolite, absolute ethanol, and γ-aminopropyltriethoxysilane, stir well for 23 min, and after the stirring ends, wash and dry to obtain modified sepiolite; the reaction mass ratio of sepiolite and γ-aminopropyltriethoxysilane is 17:1;

[0044] Add the modified silica hybrid graphene material and triethylamine to tetrahydrofuran, stir well, and then successively dropwise add the modified sepiolite solution and the aminated polyacrylate microsphere solution. After the dropping ends, reflux and react at 62 °C for 3.5 h, then dropwise add deionized water and continue to react for 3.5 h, and then cool down to 23 °C and continue to react for 11 h. After the reaction ends, centrifuge, wash, and vacuum dry to obtain the flame-retardant modified silica hybrid graphene material; dissolve the modified sepiolite in tetrahydrofuran to obtain the modified sepiolite solution; dissolve the aminated polyacrylate microspheres in tetrahydrofuran to obtain the aminated polyacrylate microsphere solution; the reaction mass ratio of the modified silica hybrid graphene material, triethylamine, modified sepiolite, aminated polyacrylate microspheres, and deionized water is 3:13:2.2:3.3:0.5;

[0045] Step 4: Mix 80 g of natural rubber, 30 g of nitrile rubber, 25 g of the flame-retardant modified silica hybrid graphene material, 5 g of sulfur, 10 g of dioctyl phthalate, 3 g of 2,6-di-tert-butyl-4-methylphenol, and 15 g of mica powder, and knead at 160 °C for 45 min to obtain the cable compound.

[0046] Example 3: Step 1: Add graphene oxide and nano-silica to absolute ethanol respectively, then mix the two solutions, stir mechanically for 30 min, and then add dicyclohexylcarbodiimide and 4-dimethylaminopyridine, and continue to stir and react for 8 h. After the reaction ends, centrifuge, wash, dry, and grind to obtain the silica hybrid graphene material; the reaction mass ratio of graphene oxide and nano-silica is 1.1:3;

[0047] The silica hybrid graphene material was added to tetrahydrofuran, stirred thoroughly and then ultrasonically dispersed for 3 h. Triethylamine was then added dropwise, and the mixture was left to stand at 0 °C for 1 h. Then, the solution of diethyl dichlorophosphine and the solution of eugenol were slowly added dropwise, and the reaction was carried out for 2 h under a nitrogen atmosphere. Then, the temperature was raised to 60 °C and the reflux reaction was carried out for 3 h. After the reaction was completed, it was washed and dried under vacuum to obtain the modified silica hybrid graphene material; diethyl dichlorophosphine was dissolved in tetrahydrofuran to obtain the diethyl dichlorophosphine solution; eugenol was dissolved in tetrahydrofuran to obtain the eugenol solution; the reaction mass ratio of the silica hybrid graphene material, diethyl dichlorophosphine, eugenol, and triethylamine was 0.1:0.42:0.23:1;

[0048] Step 2: Methyl methacrylate and diphenyl chlorophosphate were respectively dissolved in tetrahydrofuran to obtain the methyl methacrylate solution and the diphenyl chlorophosphate solution; triethylamine was added to the methyl methacrylate solution, stirred thoroughly and then the diphenyl chlorophosphate solution was added dropwise, and the reflux reaction was carried out at 60 °C for 20 h. After the reaction was completed, it was filtered, rotary evaporated, extracted, and dried to obtain phosphoacrylate; the reaction mass ratio of methyl methacrylate, diphenyl chlorophosphate, and triethylamine was 19:32:19;

[0049] Methyl methacrylate and hexachlorocyclotriphosphazene were respectively dissolved in tetrahydrofuran to obtain the methyl methacrylate solution and the hexachlorocyclotriphosphazene solution; triethylamine was added to the methyl methacrylate solution, stirred thoroughly and then the hexachlorocyclotriphosphazene solution was added dropwise, and the reflux reaction was carried out at 60 °C for 20 h. After the reaction was completed, it was filtered, rotary evaporated, extracted, and dried to obtain phosphazene acrylate; the reaction mass ratio of methyl methacrylate, hexachlorocyclotriphosphazene, and triethylamine was 19:10:19;

[0050] Methyl methacrylate, methacrylamide, phosphoacrylate, and phosphazene acrylate were added to deionized water, and then polyvinylpyrrolidone was added. The temperature was raised to 70 °C under a nitrogen atmosphere, and then 2,2'-azobis(2-methylpropionamidine) dihydrochloride was added and the reaction was continued for 6 h. After the reaction was completed, it was cooled, centrifuged, washed, dried, and ground to obtain polyacrylate microspheres; the polyacrylate microspheres were added to deionized water, ultrasonically dispersed for 20 min and then the temperature was raised to 70 °C, and then sodium hydroxide and ethylenediamine were added and the reaction was carried out for 10 h. After the reaction was completed, it was cooled, suction filtered, washed, dried, and ground to obtain aminated polyacrylate microspheres; the reaction molar ratio of methyl methacrylate, methacrylamide, phosphoacrylate, and phosphazene acrylate was 2.5:1:2:2.5; the reaction mass ratio of the polyacrylate microspheres, sodium hydroxide, and ethylenediamine was 5:0.9:19;

[0051] Step 3: Mix sepiolite, anhydrous ethanol, and γ-aminopropyltriethoxysilane, and stir well for 20 min. After stirring, wash and dry to obtain modified sepiolite; the reaction mass ratio of sepiolite to γ-aminopropyltriethoxysilane is 17:1;

[0052] Add the modified silica hybrid graphene material and triethylamine to tetrahydrofuran, stir well, and then successively add the modified sepiolite solution and the aminated polyacrylate microsphere solution dropwise. After the addition is complete, reflux and react at 60 °C for 3 h, then add deionized water and continue to react for 3 h, and then cool down to 20 °C and continue to react for 10 h. After the reaction is complete, centrifuge, wash, and vacuum dry to obtain the flame-retardant modified silica hybrid graphene material; dissolve the modified sepiolite in tetrahydrofuran to obtain the modified sepiolite solution; dissolve the aminated polyacrylate microspheres in tetrahydrofuran to obtain the aminated polyacrylate microsphere solution; the reaction mass ratio of the modified silica hybrid graphene material, triethylamine, modified sepiolite, aminated polyacrylate microspheres, and deionized water is 3:13:2.2:3.3:0.5;

[0053] Step 4: Mix 80 g of natural rubber, 30 g of nitrile rubber, 25 g of the flame-retardant modified silica hybrid graphene material, 5 g of sulfur, 10 g of dioctyl phthalate, 3 g of 2,6-di-tert-butyl-4-methylphenol, and 15 g of mica powder, and knead at 150 °C for 40 min to obtain the cable compound.

[0054] Comparative Example 1: Remove the aminated polyacrylate microspheres, and the rest is the same as in Example 1. The specific steps are as follows: Step 1: Add graphene oxide and nano-silica to anhydrous ethanol respectively, then mix the two solutions, stir mechanically for 40 min, then add dicyclohexylcarbodiimide and 4-dimethylaminopyridine, and continue to stir and react for 10 h. After the reaction is complete, centrifuge, wash, dry, and grind to obtain the silica hybrid graphene material; the reaction mass ratio of graphene oxide to nano-silica is 1.1:3;

[0055] Add the silica hybrid graphene material to tetrahydrofuran, stir well, ultrasonically disperse for 4 h, then add triethylamine dropwise, let stand at 3 °C for 2 h, then slowly add the diethyldichlorophosphorus solution and the eugenol solution, react in a nitrogen environment for 3 h, then heat up to 65 °C and reflux and react for 4 h. After the reaction is complete, wash and vacuum dry to obtain the modified silica hybrid graphene material; dissolve diethyldichlorophosphorus in tetrahydrofuran to obtain the diethyldichlorophosphorus solution; dissolve eugenol in tetrahydrofuran to obtain the eugenol solution; the reaction mass ratio of the silica hybrid graphene material, diethyldichlorophosphorus, eugenol, and triethylamine is 0.1:0.42:0.23:1;

[0056] Step 2: Mix sepiolite, absolute ethanol, and γ-aminopropyltriethoxysilane, stir well for 25 min, and after the stirring is completed, wash and dry to obtain modified sepiolite; the reaction mass ratio of sepiolite to γ-aminopropyltriethoxysilane is 17:1;

[0057] Add the modified silica hybrid graphene material and triethylamine to tetrahydrofuran, stir well, then dropwise add the modified sepiolite solution. After the addition is completed, reflux and react at 65 °C for 4 h, then dropwise add deionized water and continue to react for 4 h, and then cool down to 25 °C and continue to react for 12 h. After the reaction is completed, centrifuge, wash, and vacuum dry to obtain the flame-retardant modified silica hybrid graphene material; dissolve the modified sepiolite in tetrahydrofuran to obtain the modified sepiolite solution; the reaction mass ratio of the modified silica hybrid graphene material, triethylamine, modified sepiolite, and deionized water is 3:13:2.2:0.5;

[0058] Step 3: Mix 80 g of natural rubber, 30 g of nitrile rubber, 25 g of the flame-retardant modified silica hybrid graphene material, 5 g of sulfur, 10 g of dioctyl phthalate, 3 g of 2,6-di-tert-butyl-4-methylphenol, and 15 g of mica powder, and knead at 170 °C for 50 min to obtain the cable compound.

[0059] Comparative Example 2: Remove the aminated polyacrylate microspheres and modified sepiolite, and the rest is the same as in Example 1. The specific steps are as follows: Step 1: Add graphene oxide and nano-silica to absolute ethanol respectively, then mix the two solutions, stir mechanically for 40 min, then add dicyclohexylcarbodiimide and 4-dimethylaminopyridine, and continue to stir and react for 10 h. After the reaction is completed, centrifuge, wash, dry, and grind to obtain the silica hybrid graphene material; the reaction mass ratio of graphene oxide to nano-silica is 1.1:3;

[0060] Add the silica hybrid graphene material to tetrahydrofuran, stir well, ultrasonically disperse for 4 h, then dropwise add triethylamine, let stand at 3 °C for 2 h, then slowly dropwise add the diethyldichlorophosphorus solution and eugenol solution, react in a nitrogen environment for 3 h, then heat up to 65 °C and reflux and react for 4 h. After the reaction is completed, wash and vacuum dry to obtain the modified silica hybrid graphene material; dissolve diethyldichlorophosphorus in tetrahydrofuran to obtain the diethyldichlorophosphorus solution; dissolve eugenol in tetrahydrofuran to obtain the eugenol solution; the reaction mass ratio of the silica hybrid graphene material, diethyldichlorophosphorus, eugenol, and triethylamine is 0.1:0.42:0.23:1;

[0061] Step 2: Mix 80 g of natural rubber, 30 g of nitrile rubber, 25 g of modified silica hybrid graphene material, 5 g of sulfur, 10 g of dioctyl phthalate, 3 g of 2,6-di-tert-butyl-4-methylphenol, and 15 g of mica powder, and knead at 170 °C for 50 min to obtain cable compound.

[0062] Detection test:

[0063] Limiting oxygen index test: The cable compound prepared by the present invention is extruded and granulated, and then melt-extruded to obtain an insulating protective sleeve. Taking this insulating protective sleeve as a specimen, referring to the standard of GB / T 2406-1993 "Test Method for Oxygen Index of Plastics Combustion Performance", the specimen size is: 150×10×4 mm, and record the oxygen index value.

[0064] Mechanical property test: The cable compound prepared by the present invention is extruded and granulated, and then melt-extruded to obtain an insulating protective sleeve. Taking this insulating protective sleeve as a specimen, referring to the standard of GB / T 1040.2-2022 "Determination of Tensile Properties of Plastics - Part 2: Test Conditions for Moulded and Extruded Plastics", the specimen size is: 160×10×4 mm, and record the tensile strength. The results are as follows in the table:

[0065] Oxygen index / % <![CDATA[Tensile strength / MPa > Example 1 33.5 33.7 Example 2 33.4 33.6 Example 3 33.2 33.4 Comparative Example 1 27.1 30.7 Comparative Example 2 24.3 28.3

[0066] Conclusion: The dosages in Examples 1 - 3 remain unchanged, and only some reaction parameters are modified. From the experimental data, it can be seen that the various properties of the specimens do not show obvious fluctuations.

[0067] Comparative example 1: Remove the aminated polyacrylate microspheres, and the rest is the same as in Example 1. From the experimental data, it can be seen that compared with Example 1, the oxygen index is reduced to 27.1%, and the tensile strength is reduced to 30.7 MPa. The reason for analysis is that the aminated polyacrylate microspheres have good flame retardant properties and can effectively improve the dispersion of graphene materials. Therefore, after removing them, the flame retardant performance and mechanical properties decline.

[0068] Comparative example 2: Remove the aminated polyacrylate microspheres and modified sepiolite, and the rest is the same as in Example 1. From the experimental data, it can be seen that compared with Example 1, the oxygen index is reduced to 24.3%, and the tensile strength is reduced to 28.3 MPa. The reason for analysis is that the aminated polyacrylate microspheres and modified sepiolite have good flame retardant properties and can effectively improve the dispersion of graphene materials. Therefore, after removing them, the flame retardant performance and mechanical properties decline.

[0069] It should be noted that in this document, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variant thereof are intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or elements inherent to such process, method, article or device.

[0070] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. The production process of a high tear-resistant, oil-resistant, double-crosslinked, low-smoke, halogen-free flame-retardant cable compound, characterized in that: It includes the following steps: Step 1: Add the silica hybrid graphene material to tetrahydrofuran, stir well, ultrasonically disperse for 3 - 4 h, then add triethylamine, let it stand at 0 - 3 °C for 1 - 2 h, and then slowly add the diethyldichlorophosphine solution and eugenol solution, react for 2 - 3 h under a nitrogen atmosphere, then raise the temperature to 60 - 65 °C and reflux for 3 - 4 h. After the reaction is completed, wash and vacuum dry to obtain the modified silica hybrid graphene material; Step 2: Add methyl methacrylate, methacrylamide, phosphoric acid acrylate, and phosphazene acrylate to deionized water, then add polyvinylpyrrolidone, raise the temperature to 70 - 80 °C under a nitrogen atmosphere, and then add 2,2'-azobis(2-methylpropionamidine) dihydrochloride and continue to react for 6 - 8 h. After the reaction is completed, cool, centrifuge, wash, dry, and grind to obtain polyacrylate microspheres; Add the polyacrylate microspheres to deionized water, ultrasonically disperse for 20 - 30 min, then raise the temperature to 70 - 80 °C, and then add sodium hydroxide and ethylenediamine and react for 10 - 12 h. After the reaction is completed, cool, filter, wash, dry, and grind to obtain aminated polyacrylate microspheres; Step 3: Add the modified silica hybrid graphene material and triethylamine to tetrahydrofuran, stir well, and then sequentially add the modified sepiolite solution and aminated polyacrylate microsphere solution. After the addition is completed, reflux at 60 - 65 °C for 3 - 4 h, then add deionized water and continue to react for 3 - 4 h, and then cool to 20 - 25 °C and continue to react for 10 - 12 h. After the reaction is completed, centrifuge, wash, and vacuum dry to obtain the flame-retardant modified silica hybrid graphene material; Step 4: Mix natural rubber, nitrile rubber, flame-retardant modified silica hybrid graphene material, vulcanizing agent, plasticizer, antioxidant, and mica powder, and knead at 150 - 170 °C for 40 - 50 min to obtain the cable compound.

2. The production process of a highly tear-resistant, oil-resistant, double-crosslinked, low-smoke, halogen-free flame-retardant cable compound according to claim 1, characterized in that: In Step 1, dissolve diethyldichlorophosphine in tetrahydrofuran to obtain the diethyldichlorophosphine solution; dissolve eugenol in tetrahydrofuran to obtain the eugenol solution; the reaction mass ratio of the silica hybrid graphene material, diethyldichlorophosphine, eugenol, and triethylamine is 0.1:(0.4 - 0.45):(0.2 - 0.25):

1.

3. The production process of a highly tear-resistant, oil-resistant, double-crosslinked, low-smoke, halogen-free flame-retardant cable compound according to claim 2, characterized in that: The preparation process of the silica hybrid graphene material is as follows: Add graphene oxide and nano-silica to anhydrous ethanol respectively, then mix the two solutions, mechanically stir for 30 - 40 min, and then add dicyclohexylcarbodiimide and 4-dimethylaminopyridine, and continue to stir and react for 8 - 10 h. After the reaction is completed, centrifuge, wash, dry, and grind to obtain the silica hybrid graphene material; the reaction mass ratio of graphene oxide and nano-silica is (1.0 - 1.2):

3.

4. The production process of a high tear-resistant, oil-resistant, double-crosslinked, low-smoke, halogen-free flame-retardant cable compound according to claim 1, characterized in that: In Step 2, the reaction molar ratio of methyl methacrylate, methacrylamide, phosphoric acid acrylate, and phosphazene acrylate is (2 - 3):1:2:(2 - 3); the reaction mass ratio of polyacrylate microspheres, sodium hydroxide, and ethylenediamine is 5:0.9:(18 - 20).

5. The production process of a highly tear-resistant, oil-resistant, double-crosslinked, low-smoke, halogen-free flame-retardant cable sheath material according to claim 4, characterized in that: The preparation process of phosphoric acid acrylate is as follows: Hydroxyethyl methacrylate and diphenyl chlorophosphate are respectively dissolved in tetrahydrofuran to obtain a hydroxyethyl methacrylate solution and a diphenyl chlorophosphate solution; Triethylamine is added to the hydroxyethyl methacrylate solution, and after sufficient stirring, the diphenyl chlorophosphate solution is added dropwise, and the mixture is refluxed and reacted at 60-65 °C for 20-25 h. After the reaction is completed, filtration, rotary evaporation, extraction, and drying are carried out to obtain phosphoric acid acrylate; The preparation process of phosphazene acrylate is as follows: Hydroxyethyl methacrylate and hexachlorocyclotriphosphazene are respectively dissolved in tetrahydrofuran to obtain a hydroxyethyl methacrylate solution and a hexachlorocyclotriphosphazene solution; Triethylamine is added to the hydroxyethyl methacrylate solution, and after sufficient stirring, the hexachlorocyclotriphosphazene solution is added dropwise, and the mixture is refluxed and reacted at 60-65 °C for 20-25 h. After the reaction is completed, filtration, rotary evaporation, extraction, and drying are carried out to obtain phosphazene acrylate.

6. The production process of a highly tear-resistant, oil-resistant, double-crosslinked, low-smoke, halogen-free flame-retardant cable compound according to claim 5, characterized in that: The reaction mass ratio of hydroxyethyl methacrylate, diphenyl chlorophosphate, and triethylamine is (18-20):32:19; The reaction mass ratio of hydroxyethyl methacrylate, hexachlorocyclotriphosphazene, and triethylamine is (18-20):10:

19.

7. The production process of a highly tear-resistant, oil-resistant, double-crosslinked, low-smoke, halogen-free flame-retardant cable compound according to claim 1, characterized in that: In step three, the modified sepiolite is dissolved in tetrahydrofuran to obtain a modified sepiolite solution; The aminated polyacrylate microspheres are dissolved in tetrahydrofuran to obtain an aminated polyacrylate microsphere solution; The reaction mass ratio of the modified silica hybrid graphene material, triethylamine, modified sepiolite, aminated polyacrylate microspheres, and deionized water is 3:13:(2-2.5):(3-3.5):0.

5.

8. The production process of a highly tear-resistant, oil-resistant, double-crosslinked, low-smoke, halogen-free flame-retardant cable compound according to claim 7, characterized in that: The preparation process of the modified sepiolite is as follows: Sepiolite, anhydrous ethanol, and γ-aminopropyltriethoxysilane are mixed and stirred sufficiently for 20-25 min. After the stirring is completed, washing and drying are carried out to obtain the modified sepiolite; The reaction mass ratio of sepiolite and γ-aminopropyltriethoxysilane is (15-20):

1.

9. The production process of a highly tear-resistant, oil-resistant, double-crosslinked, low-smoke, halogen-free flame-retardant cable compound according to claim 1, characterized in that: In step four, the content of each component of the cable sheath material is as follows: in terms of mass parts, 70-80 parts of natural rubber, 20-30 parts of nitrile rubber, 18-25 parts of flame-retardant modified silica hybrid graphene material, 3-5 parts of vulcanizing agent, 5-10 parts of plasticizer, 2-3 parts of antioxidant, and 10-15 parts of mica powder; The vulcanizing agent is sulfur; The plasticizer is dioctyl phthalate; The antioxidant is 2,6-di-tert-butyl-4-methylphenol.

10. A high tear-resistant, oil-resistant, double-crosslinked, low-smoke, halogen-free flame-retardant cable compound, characterized in that, Produced according to the production process described in any one of claims 1-9.