High-flame-retardant and high-temperature-resistant cable sheath material and preparation method thereof

Abstract

The invention relates to the field of cable sheath materials, in particular to a high-flame-retardant and high-temperature-resistant cable sheath material and a preparation method thereof, which are used for solving the problem that the application of an existing cable sheath material in the field of high-end and high-safety cables is seriously limited due to poor flame retardance and high-temperature resistance of the existing cable sheath material. According to the cable sheath material, polyethylene and polypropylene are used as basic resin, the cable sheath material is endowed with excellent mechanical properties, good safety and reliability are provided for a cable, DOPO-amino triazine compounds and modified magnesium hydroxide are added to serve as synergistic flame retardants, and the flame retardancy of the cable sheath material is improved. The flame-retardant and high-temperature-resistant cable sheath material has the advantages that the flame-retardant and high-temperature-resistant properties of the cable sheath material can be obviously improved, cable fires can be effectively prevented, and the structural and functional stability can be continuously kept in a high-temperature environment, so that the stable work of the cable can be ensured in a high-temperature condition, and the cable can be effectively protected in an extreme condition; and the safety of the cable is improved.

Description

Technical Field

[0001] This invention relates to the field of cable sheath materials, specifically to a high flame-retardant and high-temperature resistant cable sheath material and its preparation method. Background Technology

[0002] Cables are widely used in modern industry and daily life, such as in power transmission, building power supply, and industrial automation. The cable sheath is a crucial component of the cable, its primary function being to protect the internal conductors from external environmental influences and extend the cable's lifespan. However, traditional cable sheath materials often use polymers, whose inherent flammability and low heat resistance may cause them to lose their protective effect or even contribute to combustion when exposed to high temperatures and fires, severely limiting their application in high-end, high-safety cable applications.

[0003] Therefore, it is particularly important to develop a high flame-retardant and high-temperature resistant cable sheath material and its preparation method. Summary of the Invention

[0004] In order to overcome the above-mentioned technical problems, the purpose of this invention is to provide a high flame retardant and high temperature resistant cable sheath material and its preparation method, which solves the problem that the existing cable sheath materials have poor flame retardant and high temperature resistant properties, which seriously limit their application in the field of high-end and high-safety cables.

[0005] The objective of this invention can be achieved through the following technical solutions: In a first aspect, this application provides a high flame-retardant and high-temperature resistant cable sheath material, comprising the following components by weight: The matrix resin contains 60-70 parts, the synergistic flame retardant contains 16-22 parts, the toughening agent contains 6-8 parts, the lubricant contains 2-4 parts, and the antioxidant contains 1-2 parts. The matrix resin is a mixture of high-density polyethylene HYA 800 and polypropylene K8003 in a mass ratio of 5:2-3; the synergistic flame retardant is a mixture of DOPO-aminotriazine compound and modified magnesium hydroxide in a mass ratio of 1-3:6. The DOPO-aminotriazine compound is prepared by the following steps: Step a1: 5-chloro-2,4-dinitrotoluene, cyanuric acid, potassium hydroxide, ethanol, and N,N-dimethylformamide were added to a three-necked flask equipped with a stirrer and a thermometer. The mixture was stirred and reacted for 20-30 minutes at a temperature of 20-25°C and a stirring rate of 200-300 r / min. After that, the temperature was raised to 80-90°C and the mixture was stirred and reacted for 8-10 hours. After the reaction was completed, the reaction product was filtered under vacuum while hot. The solvent was removed by rotary evaporation of the filtrate. The filtrate was then poured into distilled water and filtered under vacuum. The filter cake was placed in a vacuum drying oven and dried for 2-3 hours at a temperature of 50-60°C to obtain the hexanitrotriazine compound. Step a2: Add hexanitrotriazine compound, palladium on carbon, ethanol and N,N-dimethylformamide to a reaction vessel. Stir the reaction at 20-25℃ and 200-300 r / min for 10-20 min. Then raise the temperature to 70-80℃ and continue stirring the reaction at 0.7-0.8 MPa for 6-10 h. After the reaction is complete, filter the reaction product under vacuum while hot. Pour the filtrate into ice water and let it stand to precipitate. Then filter under vacuum and recrystallize the filter cake with ethanol to obtain hexanitrotriazine compound. Step a3: Add the hexaaminotriazine compound, DOPO, anhydrous potassium carbonate, and dichloromethane to a three-necked flask equipped with a stirrer, thermometer, gas delivery tube, and constant-pressure dropping funnel. Purge with nitrogen for protection and stir the reaction at 0-3℃ and a stirring rate of 200-300 r / min for 1-2 h. Then, add carbon tetrachloride dropwise while stirring, controlling the dropping rate to 1-3 drops / s. After the addition is complete, raise the temperature to 25-30℃ and continue stirring the reaction for 10-15 h. After the reaction is complete, filter the reaction product under vacuum. Wash the filter cake 2-3 times with distilled water and then place it in a vacuum drying oven at 70-80℃ for 3-5 h to obtain the DOPO-aminotriazine compound.

[0006] In a preferred embodiment of the present invention, the ratio of 5-chloro-2,4-dinitrotoluene, cyanuric acid, potassium hydroxide, ethanol and N,N-dimethylformamide in step a1 is 33-39 mmol: 10 mmol: 40-50 mmol: 40-50 mL: 30-40 mL.

[0007] In a preferred embodiment of the present invention, the ratio of the hexanitrotriazine compound, palladium on carbon, ethanol and N,N-dimethylformamide used in step a2 is 5g:2-3g:30-35mL:15-25mL.

[0008] In a preferred embodiment of the present invention, the mass percentage of palladium metal in the palladium carbon in step a2 is 10%.

[0009] In a preferred embodiment of the present invention, the ratio of the hexaaminotriazine compound, DOPO, anhydrous potassium carbonate, dichloromethane and carbon tetrachloride in step a3 is 10 mmol: 66-72 mmol: 75-80 mmol: 70-80 mL: 70-80 mmol.

[0010] In a preferred embodiment of the present invention, the modified magnesium hydroxide is prepared by the following steps: Magnesium hydroxide, ethanol, and deionized water were added to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Nitrogen gas was introduced for protection, and the mixture was stirred for 20-30 minutes at a temperature of 25-30℃ and a stirring rate of 200-300 r / min. Then, oleic acid was added, and the mixture was heated to 60-70℃ and stirred for another 1-5 hours. After the reaction was completed, the reaction product was vacuum filtered. The filter cake was washed 2-3 times with distilled water and then placed in a vacuum drying oven and dried at 80-90℃ for 2-3 hours to obtain modified magnesium hydroxide.

[0011] In a preferred embodiment of the present invention, the ratio of magnesium hydroxide, ethanol, deionized water and oleic acid is 5g:20-25mL:30-35mL:0.8-2.6g; the average particle size of the magnesium hydroxide is 500 mesh.

[0012] Secondly, this application provides a method for preparing a high flame-retardant and high-temperature resistant cable sheath material, comprising the following steps: Step 1: Weigh out 60-70 parts of the base resin, 16-22 parts of the synergistic flame retardant, 6-8 parts of the toughening agent, 2-4 parts of the lubricant, and 1-2 parts of the antioxidant according to the weight ratio, and set aside. Step 2: Add the base resin, synergistic flame retardant, toughening agent, lubricant, and antioxidant to a high-speed mixer and mix for 20-40 minutes at a temperature of 70-80℃ and a stirring rate of 800-1200 r / min. Then add it to a twin-screw extruder and melt-extrude it at temperatures of 160℃ in zone 1, 175℃ in zone 2, 185℃ in zone 3, 190℃ in zone 4, 185℃ in zone 5, 180℃ at the die head, and a screw speed of 100-120 r / min. After water cooling and pelletizing, a high flame-retardant and high-temperature resistant cable sheath material is obtained.

[0013] In a preferred embodiment of the present invention, the toughening agent is POE 8407.

[0014] In a preferred embodiment of the present invention, the lubricant is a mixture of calcium stearate and polyethylene wax in a mass ratio of 2:1.

[0015] In a preferred embodiment of the present invention, the antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:3.

[0016] Compared with the prior art, the beneficial effects of the present invention are: This invention discloses a high flame-retardant and high-temperature resistant cable sheath material and its preparation method. The method involves mixing a base resin, a synergistic flame retardant, a toughening agent, a lubricant, and an antioxidant, followed by melt extrusion, water cooling, and pelletizing to obtain the high flame-retardant and high-temperature resistant cable sheath material. This cable sheath material utilizes polyethylene and polypropylene as base resins, imparting excellent mechanical properties and providing good safety and reliability for the cable. Adding DOPO-aminotriazine compounds and modified magnesium hydroxide as synergistic flame retardants significantly improves the flame-retardant and high-temperature resistant properties of the cable sheath material. This not only effectively prevents cable fires but also maintains structural and functional stability under high-temperature environments, ensuring stable cable operation even at high temperatures. It provides effective protection for cables under extreme conditions, thus improving cable safety.

[0017] In the preparation of cable sheath materials, a synergistic flame retardant was first prepared. This involved the reaction of 5-chloro-2,4-dinitrotoluene and cyanuric acid. The chlorine atom on 5-chloro-2,4-dinitrotoluene reacted with the hydroxyl group on cyanuric acid, introducing multiple nitro groups to obtain a hexanitrotriazine compound. Hydrogen gas was then used to reduce the nitro groups on the hexanitrotriazine compound to amino groups, yielding a hexaaminotriazine compound. The hexaaminotriazine compound was then reacted with DOPO. Under the action of carbon tetrachloride, the active hydrogen in the pH bond of DOPO was replaced by a chlorine atom, generating a highly active P-Cl bond. Subsequently, the chlorine atom reacted with the amino group on the hexaaminotriazine compound, introducing multiple DOPO structures to obtain a DOPO-aminotriazine compound. Oleic acid was then used to modify magnesium hydroxide. First, hydrogen bonds were used to attract the hydroxide to the surface of the magnesium hydroxide. Then, the carboxyl group on the oleic acid reacted with the hydroxide... The hydroxyl groups on magnesium react to form long carbon links on the surface of magnesium hydroxide, resulting in modified magnesium hydroxide. Finally, a DOPO-aminotriazine compound and the modified magnesium hydroxide are rationally compounded to obtain a synergistic flame retardant. During combustion and decomposition, this modified magnesium hydroxide releases water vapor to dilute combustible gases and oxygen. The decomposition product, MgO, also coats the material surface, forming a heat-insulating and oxygen-barrier protective carbon layer, achieving a flame-retardant effect. The modification with long carbon links ensures good dispersion in the matrix, allowing for more uniform and effective action. The DOPO-aminotriazine compound contains multiple cyclic structures, giving it excellent high-temperature resistance. Furthermore, the molecule contains multiple organophosphorus and organonitrogen structures, which can efficiently capture active free radicals in the flame, interrupting chain reactions. It can also decompose and release non-combustible gases such as nitrogen, further diluting the gas phase. The synergistic effect of these two factors results in excellent flame-retardant performance. Therefore, adding a synergistic flame retardant to cable sheath materials can significantly improve their high flame-retardant and high-temperature resistance effects. Detailed Implementation

[0018] To enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Example 1: This embodiment describes a method for preparing a high flame-retardant and high-temperature resistant cable sheath material, comprising the following steps: Step S1: 33 mmol of 5-chloro-2,4-dinitrotoluene, 10 mmol of cyanuric acid, 40 mmol of potassium hydroxide, 40 mL of ethanol and 30 mL of N,N-dimethylformamide were added to a three-necked flask equipped with a stirrer and a thermometer. The mixture was stirred at 20 °C and a stirring rate of 200 r / min for 20 min. After that, the mixture was heated to 80 °C and stirred for another 8 h. After the reaction was completed, the reaction product was filtered under vacuum while hot. The solvent was removed by rotary evaporation of the filtrate. The filtrate was then poured into distilled water and filtered under vacuum. The filter cake was placed in a vacuum drying oven and dried at 50 °C for 2 h to obtain the hexanitrotriazine compound. Step S2: Add 5g of hexanitrotriazine compound, 2g of palladium metal (10% by mass) on carbon, 30mL of ethanol, and 15mL of N,N-dimethylformamide to a reaction vessel. Stir the reaction at 20℃ and 200r / min for 10min. Then, raise the temperature to 70℃ and continue stirring at 0.7MPa for 6h. After the reaction is complete, filter the reaction product under vacuum while hot. Pour the filtrate into ice water and let it stand to precipitate. Then, filter under vacuum and recrystallize the filter cake with ethanol to obtain hexaaminotriazine compound. Step S3: 10 mmol of hexaaminotriazine compound, 66 mmol of DOPO, 75 mmol of anhydrous potassium carbonate and 70 mL of dichloromethane were added to a three-necked flask equipped with a stirrer, thermometer, gas delivery tube and constant pressure dropping funnel. Nitrogen gas was introduced for protection, and the reaction was stirred at 0 °C and 200 r / min for 1 h. Then, 70 mmol of carbon tetrachloride was added dropwise while stirring, with the dropping rate controlled at 1 drop / s. After the addition was completed, the temperature was raised to 25 °C and the reaction was stirred for another 10 h. After the reaction was completed, the reaction product was vacuum filtered, the filter cake was washed twice with distilled water, and then placed in a vacuum drying oven and dried at 70 °C for 3-5 h to obtain DOPO-aminotriazine compound. Step S4: Add 5g of magnesium hydroxide with an average particle size of 500 mesh, 20mL of ethanol and 30mL of deionized water to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Purge with nitrogen for protection and stir for 20min at 25℃ and 200r / min. Then add 0.8g of oleic acid and continue stirring for 1h at 60℃. After the reaction is complete, filter the reaction product under vacuum. Wash the filter cake twice with distilled water and then place it in a vacuum drying oven and dry at 80℃ for 2h to obtain modified magnesium hydroxide. Step S5: Weigh out 60 parts by weight of the base resin, 16 parts by weight of the synergistic flame retardant, 6 parts by weight of the toughening agent, 2 parts by weight of the lubricant, and 1 part by weight of the antioxidant, and set aside. The base resin is a mixture of high-density polyethylene HYA 800 and polypropylene K8003 in a mass ratio of 5:2. The synergistic flame retardant is a mixture of DOPO-aminotriazine compound and modified magnesium hydroxide in a mass ratio of 1:6. The toughening agent is POE 8407. The lubricant is a mixture of calcium stearate and polyethylene wax in a mass ratio of 2:1. The antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:3. Step S6: Add the matrix resin, synergistic flame retardant, toughening agent, lubricant and antioxidant to a high-speed mixer and mix for 20 minutes at a temperature of 70°C and a stirring rate of 800 r / min. Then add it to a twin-screw extruder and melt-extrude it at the following conditions: zone 1 160°C, zone 2 175°C, zone 3 185°C, zone 4 190°C, zone 5 185°C, die head 180°C and screw speed 100 r / min. After water cooling and pelletizing, a high flame retardant and high temperature resistant cable sheath material is obtained.

[0020] Example 2: This embodiment describes a method for preparing a high flame-retardant and high-temperature resistant cable sheath material, comprising the following steps: Step S1: 36 mmol of 5-chloro-2,4-dinitrotoluene, 10 mmol of cyanuric acid, 45 mmol of potassium hydroxide, 45 mL of ethanol and 35 mL of N,N-dimethylformamide were added to a three-necked flask equipped with a stirrer and a thermometer. The mixture was stirred at 22 °C and 250 r / min for 25 min. After stirring, the mixture was heated to 85 °C and stirred for 9 h. After the reaction was completed, the reaction product was filtered under vacuum while hot. The solvent was removed by rotary evaporation of the filtrate. The filtrate was then poured into distilled water and filtered under vacuum. The filter cake was placed in a vacuum drying oven and dried at 55 °C for 2.5 h to obtain the hexanitrotriazine compound. Step S2: 5g of hexanitrotriazine compound, 2.5g of palladium metal (10% by mass) on carbon, 32mL of ethanol, and 20mL of N,N-dimethylformamide were added to a reaction vessel. The mixture was stirred at 22℃ and 250r / min for 15min. Then, the temperature was raised to 75℃ and hydrogen gas was introduced to maintain a pressure of 0.75MPa. The mixture was stirred for another 8h. After the reaction was completed, the reaction product was filtered under vacuum while hot. The filtrate was poured into ice water and allowed to stand to precipitate. The precipitate was then filtered under vacuum and recrystallized from the filter cake with ethanol to obtain the hexanitrotriazine compound. Step S3: 10 mmol of hexaaminotriazine compound, 69 mmol of DOPO, 78 mmol of anhydrous potassium carbonate and 75 mL of dichloromethane were added to a three-necked flask equipped with a stirrer, thermometer, gas delivery tube and constant pressure dropping funnel. Nitrogen gas was introduced for protection, and the reaction was stirred at 1 °C and 250 r / min for 1.5 h. Then, 75 mmol of carbon tetrachloride was added dropwise while stirring, with the dropping rate controlled at 2 drops / s. After the addition was completed, the temperature was raised to 28 °C and the reaction was stirred for another 12 h. After the reaction was completed, the reaction product was vacuum filtered, the filter cake was washed twice with distilled water, and then placed in a vacuum drying oven and dried at 75 °C for 4 h to obtain DOPO-aminotriazine compound. Step S4: Add 5g of magnesium hydroxide with an average particle size of 500 mesh, 22mL of ethanol and 32mL of deionized water to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Purge with nitrogen for protection and stir at 28℃ and 250r / min for 25min. Then add 1.7g of oleic acid and continue stirring at 65℃ for 3h. After the reaction is complete, filter the reaction product under vacuum. Wash the filter cake twice with distilled water and then place it in a vacuum drying oven and dry at 85℃ for 2.5h to obtain modified magnesium hydroxide. Step S5: Weigh out 65 parts by weight of the base resin, 19 parts by weight of the synergistic flame retardant, 7 parts by weight of the toughening agent, 3 parts by weight of the lubricant, and 1.5 parts by weight of the antioxidant, and set aside. The base resin is a mixture of high-density polyethylene HYA 800 and polypropylene K8003 in a mass ratio of 5:2.5. The synergistic flame retardant is a mixture of DOPO-aminotriazine compound and modified magnesium hydroxide in a mass ratio of 2:6. The toughening agent is POE 8407. The lubricant is a mixture of calcium stearate and polyethylene wax in a mass ratio of 2:1. The antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:3. Step S6: Add the matrix resin, synergistic flame retardant, toughening agent, lubricant and antioxidant to a high-speed mixer and mix for 30 minutes at a temperature of 75°C and a stirring rate of 1000 r / min. Then add it to a twin-screw extruder and melt-extrude it under the following conditions: temperature set at 160°C in zone 1, 175°C in zone 2, 185°C in zone 3, 190°C in zone 4, 185°C in zone 5, 180°C at the die head, and screw speed of 110 r / min. After water cooling and pelletizing, a high flame retardant and high temperature resistant cable sheath material is obtained.

[0021] Example 3: This embodiment describes a method for preparing a high flame-retardant and high-temperature resistant cable sheath material, comprising the following steps: Step S1: 39 mmol of 5-chloro-2,4-dinitrotoluene, 10 mmol of cyanuric acid, 50 mmol of potassium hydroxide, 50 mL of ethanol and 40 mL of N,N-dimethylformamide were added to a three-necked flask equipped with a stirrer and a thermometer. The mixture was stirred at 25 °C and a stirring rate of 300 r / min for 30 min. After that, the mixture was heated to 90 °C and stirred for another 10 h. After the reaction was completed, the reaction product was filtered under vacuum while hot. The solvent was removed by rotary evaporation of the filtrate. The filtrate was then poured into distilled water and filtered under vacuum. The filter cake was placed in a vacuum drying oven and dried at 60 °C for 3 h to obtain the hexanitrotriazine compound. Step S2: Add 5g of hexanitrotriazine compound, 3g of palladium metal (10% by mass) on carbon, 35mL of ethanol, and 25mL of N,N-dimethylformamide to a reaction vessel. Stir the reaction at 25℃ and 300r / min for 20min. Then, raise the temperature to 80℃ and continue stirring the reaction at 0.8MPa for 10h. After the reaction is complete, filter the reaction product under vacuum while hot. Pour the filtrate into ice water and let it stand to precipitate. Then, filter under vacuum and recrystallize the filter cake with ethanol to obtain the hexanitrotriazine compound. Step S3: 10 mmol of hexaaminotriazine compound, 72 mmol of DOPO, 80 mmol of anhydrous potassium carbonate and 80 mL of dichloromethane were added to a three-necked flask equipped with a stirrer, thermometer, gas delivery tube and constant pressure dropping funnel. Nitrogen gas was introduced for protection and the reaction was stirred at 3°C ​​and 300 r / min for 2 h. Then, 80 mmol of carbon tetrachloride was added dropwise while stirring, with the dropping rate controlled at 3 drops / s. After the addition was completed, the temperature was raised to 30°C and the reaction was stirred for another 15 h. After the reaction was completed, the reaction product was vacuum filtered. The filter cake was washed three times with distilled water and then placed in a vacuum drying oven and dried at 80°C for 5 h to obtain DOPO-aminotriazine compound. Step S4: Add 5g of magnesium hydroxide with an average particle size of 500 mesh, 25mL of ethanol and 35mL of deionized water to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 30min. Then add 2.6g of oleic acid and continue stirring at 70℃ for 5h. After the reaction is complete, filter the reaction product under vacuum. Wash the filter cake three times with distilled water and then place it in a vacuum drying oven and dry at 90℃ for 3h to obtain modified magnesium hydroxide. Step S5: Weigh out 70 parts by weight of the base resin, 22 parts by weight of the synergistic flame retardant, 8 parts by weight of the toughening agent, 4 parts by weight of the lubricant, and 2 parts by weight of the antioxidant, and set aside. The base resin is a mixture of high-density polyethylene HYA 800 and polypropylene K8003 in a mass ratio of 5:3. The synergistic flame retardant is a mixture of DOPO-aminotriazine compound and modified magnesium hydroxide in a mass ratio of 3:6. The toughening agent is POE 8407. The lubricant is a mixture of calcium stearate and polyethylene wax in a mass ratio of 2:1. The antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:3. Step S6: Add the matrix resin, synergistic flame retardant, toughening agent, lubricant, and antioxidant to a high-speed mixer and mix for 40 minutes at a temperature of 80°C and a stirring rate of 1200 r / min. Then add the mixture to a twin-screw extruder and melt-extrude it under the following conditions: zone 1 160°C, zone 2 175°C, zone 3 185°C, zone 4 190°C, zone 5 185°C, die head 180°C, and screw speed 120 r / min. After water cooling and pelletizing, a high flame retardant and high temperature resistant cable sheath material is obtained.

[0022] Comparative Example 1: This comparative example illustrates a method for preparing a high flame-retardant and high-temperature resistant cable sheath material, comprising the following steps: Step S1: Weigh out 70 parts by weight of the base resin, 8 parts by weight of the toughening agent, 4 parts by weight of the lubricant, and 2 parts by weight of the antioxidant, and set aside. The base resin is a mixture of high-density polyethylene HYA 800 and polypropylene K8003 in a mass ratio of 5:3. The toughening agent is POE 8407. The lubricant is a mixture of calcium stearate and polyethylene wax in a mass ratio of 2:1. The antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:3. Step S2: Add the matrix resin, toughening agent, lubricant and antioxidant to a high-speed mixer and mix for 40 minutes at a temperature of 80℃ and a stirring rate of 1200r / min. Then add it to a twin-screw extruder and melt-extrude it under the following conditions: temperature set to 160℃ in zone 1, 175℃ in zone 2, 185℃ in zone 3, 190℃ in zone 4, 185℃ in zone 5, 180℃ at the die head, and screw speed of 120r / min. After water cooling and pelletizing, a high flame-retardant and high-temperature resistant cable sheath material is obtained.

[0023] Comparative Example 2: This comparative example illustrates a method for preparing a high flame-retardant and high-temperature resistant cable sheath material, comprising the following steps: Step S1: Add 5g of magnesium hydroxide with an average particle size of 500 mesh, 25mL of ethanol and 35mL of deionized water to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 30min. Then add 2.6g of oleic acid and continue stirring at 70℃ for 5h. After the reaction is complete, filter the reaction product under vacuum. Wash the filter cake three times with distilled water and then place it in a vacuum drying oven and dry at 90℃ for 3h to obtain modified magnesium hydroxide. Step S2: Weigh out 70 parts by weight of the base resin, 22 parts by weight of the modified magnesium hydroxide, 8 parts by weight of the toughening agent, 4 parts by weight of the lubricant, and 2 parts by weight of the antioxidant, and set aside. The base resin is a mixture of high-density polyethylene HYA 800 and polypropylene K8003 in a mass ratio of 5:3; the toughening agent is POE 8407; the lubricant is a mixture of calcium stearate and polyethylene wax in a mass ratio of 2:1; and the antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:3. Step S3: Add the matrix resin, modified magnesium hydroxide, toughening agent, lubricant and antioxidant to a high-speed mixer and mix for 40 minutes at a temperature of 80℃ and a stirring rate of 1200r / min. Then add it to a twin-screw extruder and melt-extrude it under the following conditions: temperature set at 160℃ in zone 1, 175℃ in zone 2, 185℃ in zone 3, 190℃ in zone 4, 185℃ in zone 5, 180℃ at the die head, and screw speed at 120r / min. After water cooling and pelletizing, a high flame-retardant and high-temperature resistant cable sheath material is obtained.

[0024] Comparative Example 1: This comparative example illustrates a method for preparing a high flame-retardant and high-temperature resistant cable sheath material, comprising the following steps: Step S1: 39 mmol of 5-chloro-2,4-dinitrotoluene, 10 mmol of cyanuric acid, 50 mmol of potassium hydroxide, 50 mL of ethanol and 40 mL of N,N-dimethylformamide were added to a three-necked flask equipped with a stirrer and a thermometer. The mixture was stirred at 25 °C and a stirring rate of 300 r / min for 30 min. After that, the mixture was heated to 90 °C and stirred for another 10 h. After the reaction was completed, the reaction product was filtered under vacuum while hot. The solvent was removed by rotary evaporation of the filtrate. The filtrate was then poured into distilled water and filtered under vacuum. The filter cake was placed in a vacuum drying oven and dried at 60 °C for 3 h to obtain the hexanitrotriazine compound. Step S2: Add 5g of hexanitrotriazine compound, 3g of palladium metal (10% by mass) on carbon, 35mL of ethanol, and 25mL of N,N-dimethylformamide to a reaction vessel. Stir the reaction at 25℃ and 300r / min for 20min. Then, raise the temperature to 80℃ and continue stirring the reaction at 0.8MPa for 10h. After the reaction is complete, filter the reaction product under vacuum while hot. Pour the filtrate into ice water and let it stand to precipitate. Then, filter under vacuum and recrystallize the filter cake with ethanol to obtain the hexanitrotriazine compound. Step S3: 10 mmol of hexaaminotriazine compound, 72 mmol of DOPO, 80 mmol of anhydrous potassium carbonate and 80 mL of dichloromethane were added to a three-necked flask equipped with a stirrer, thermometer, gas delivery tube and constant pressure dropping funnel. Nitrogen gas was introduced for protection and the reaction was stirred at 3°C ​​and 300 r / min for 2 h. Then, 80 mmol of carbon tetrachloride was added dropwise while stirring, with the dropping rate controlled at 3 drops / s. After the addition was completed, the temperature was raised to 30°C and the reaction was stirred for another 15 h. After the reaction was completed, the reaction product was vacuum filtered. The filter cake was washed three times with distilled water and then placed in a vacuum drying oven and dried at 80°C for 5 h to obtain DOPO-aminotriazine compound. Step S4: Weigh out 70 parts by weight of the base resin, 22 parts by weight of the DOPO-aminotriazine compound, 8 parts by weight of the toughening agent, 4 parts by weight of the lubricant, and 2 parts by weight of the antioxidant, and set aside. The base resin is a mixture of high-density polyethylene HYA 800 and polypropylene K8003 in a mass ratio of 5:3; the toughening agent is POE 8407; the lubricant is a mixture of calcium stearate and polyethylene wax in a mass ratio of 2:1; and the antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:3. Step S5: Add the matrix resin, DOPO-aminotriazine compound, toughening agent, lubricant and antioxidant to a high-speed mixer and mix for 40 minutes at a temperature of 80℃ and a stirring rate of 1200r / min. Then add it to a twin-screw extruder and melt extrude it under the following conditions: temperature set to 160℃ in zone 1, 175℃ in zone 2, 185℃ in zone 3, 190℃ in zone 4, 185℃ in zone 5, 180℃ at the die head, and screw speed of 120r / min. After water cooling and pelletizing, a high flame-retardant and high-temperature resistant cable sheath material is obtained.

[0025] The high flame-retardant and high-temperature resistant cable sheath materials of Examples 1-3 and Comparative Examples 1-3 were tested for vertical flammability according to UL 94 standard, limiting oxygen index according to GB / T 2406.2, and thermal stability time after 5% weight loss was tested in a 200℃ vacuum drying oven. The test results are shown in the table below:

[0026] Referring to the data in the table above, and based on the comparison between Examples 1-3 and Comparative Examples 1-3, it can be seen that adding modified magnesium hydroxide and DOPO-aminotriazine compounds can significantly improve the flame retardant and high temperature resistance properties of cable sheath materials, resulting in cable sheath materials with high flame retardant and high temperature resistance.

[0027] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0028] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in this application, they should all fall within the protection scope of the present invention.

Claims

1. A high flame retardant, high temperature resistant cable jacketing material characterized in that, Comprise the following components by mass parts: Base resin 60-70 parts, synergistic flame retardant 16-22 parts, toughening agent 6-8 parts, lubricant 2-4 parts and antioxidant 1-2 parts; Wherein, the base resin is a mixture of high density polyethylene HYA 800 and polypropylene K8003 in a mass ratio of 5:2-3; the synergistic flame retardant is a mixture of DOPO-amino triazine compound and modified magnesium hydroxide in a mass ratio of 1-3:6; Wherein, the DOPO-amino triazine compound is prepared by the following steps: Step a1: 5-chloro-2,4-dinitrotoluene, cyanuric acid, potassium hydroxide, ethanol and N, N-dimethylformamide are stirred to react, after the reaction is completed, the reaction product is filtered under vacuum while hot, the filtrate is rotary evaporated, then poured into distilled water, then filtered under vacuum, the filter cake is dried to obtain a hexanitro triazine compound; Step a2: the hexanitro triazine compound, palladium on carbon, ethanol and N, N-dimethylformamide are stirred to react, then hydrogen is introduced and the reaction is continued, after the reaction is completed, the reaction product is filtered under vacuum while hot, the filtrate is poured into ice water, then the precipitate is separated after standing, then the filter cake is recrystallized to obtain a hexamino triazine compound; Step a3: the hexamino triazine compound, DOPO, anhydrous potassium carbonate and dichloromethane are stirred to react, then carbon tetrachloride is added dropwise and the reaction is continued, after the reaction is completed, the reaction product is filtered under vacuum, the filter cake is washed and dried to obtain a DOPO-amino triazine compound.

2. A high flame retardant high temperature resistant cable jacketing material according to claim 1, characterized in that, The amount ratio of 5-chloro-2,4-dinitrotoluene, cyanuric acid, potassium hydroxide, ethanol and N, N-dimethylformamide in step a1 is 33-39 mmol:10 mmol:40-50 mmol:40-50 mL:30-40 mL.

3. A high flame retardant high temperature resistant cable jacketing material as claimed in claim 1, wherein, The amount ratio of the hexanitro triazine compound, palladium on carbon, ethanol and N, N-dimethylformamide in step a2 is 5 g:2-3 g:30-35 mL:15-25 mL; the mass ratio of palladium in the palladium on carbon is 10%.

4. A high flame retardant high temperature resistant cable jacketing material as claimed in claim 1, wherein, The amount ratio of the hexamino triazine compound, DOPO, anhydrous potassium carbonate, dichloromethane and carbon tetrachloride in step a3 is 10 mmol:66-72 mmol:75-80 mmol:70-80 mL:70-80 mmol.

5. A high flame retardant high temperature resistant cable jacketing material as claimed in claim 1, wherein, The modified magnesium hydroxide is prepared by the following steps: Magnesium hydroxide, ethanol and deionized water are stirred to react, then oleic acid is added and the reaction is continued, after the reaction is completed, the reaction product is filtered under vacuum, the filter cake is washed and dried to obtain the modified magnesium hydroxide.

6. A high flame retardant high temperature resistant cable jacketing material according to claim 5, characterized in that, The amount ratio of the magnesium hydroxide, ethanol, deionized water and oleic acid is 5 g:20-25 mL:30-35 mL:0.8-2.6 g; the average particle size of the magnesium hydroxide is 500 mesh.

7. A process for the preparation of a high flame retardant high temperature resistant cable jacketing material, characterized by, A method for preparing the high flame-retardant and high-temperature-resistant cable sheath material of any one of claims 1-6, comprising the following steps: Step one: according to the mass parts, the base resin 60-70 parts, synergistic flame retardant 16-22 parts, toughening agent 6-8 parts, lubricant 2-4 parts and antioxidant 1-2 parts, standby; Step two: the base resin, synergistic flame retardant, toughening agent, lubricant and antioxidant are added to the high-speed mixer, stirred and mixed at 70-80 DEG C, the stirring rate is 800-1200 r / min for 20-40 min, then added to the twin-screw extruder, the temperature is set to one area 160 DEG C, two area 175 DEG C, three area 185 DEG C, four area 190 DEG C, five area 185 DEG C, head 180 DEG C and screw speed 100-120 r / min, melt extrusion, water cooling, granulation, high flame retardant high temperature resistant cable sheath material is obtained.

8. A process for the preparation of a high flame retardant high temperature resistant cable jacketing material as claimed in claim 7, wherein, The toughening agent is POE 8407.

9. A process for the preparation of a high flame retardant high temperature resistant cable jacketing material as claimed in claim 8, wherein, The lubricant is a mixture of calcium stearate and polyethylene wax in a mass ratio of 2:

1.

10. A process for the preparation of a high flame retardant high temperature resistant cable jacketing material as claimed in claim 9, wherein, The antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:3.

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