High-strength flame-retardant optical cable material, optical cable and preparation method

Abstract

The invention discloses a high-strength flame-retardant optical cable material, an optical cable and a preparation method, and belongs to the technical field of optical fibers. Hydroxylation treatment is performed on nanometer magnesium oxide powder and carbon fibers, a zinc skeleton is generated on the surface in situ, and amino in the structural formula of the zinc skeleton is combined with cyano groups of side chains of nitrile rubber; the nanometer magnesium oxide powder and the carbon fibers are uniformly dispersed in the ceramic rubber composite powder, the nanometer magnesium oxide and the carbon fibers can significantly improve the overall strength and the heat conduction capability of the optical cable tight sleeve layer, and when the nitrile rubber is subjected to a hydrogenation reaction, zinc ions in the center of a zinc skeleton play a stable catalytic role, so that the optical cable tight sleeve layer is more stable. The hydrogenated nitrile rubber can significantly improve the heat resistance and aging resistance; according to the preparation method, fluorine-containing gas in a plasma state is utilized to perform fluorination modification on polyurethane through a plasma fluorination technology, so that the humidity resistance is remarkably improved, fluorinated polyurethane is subjected to amination modification, and ammonium polyphosphate can be effectively loaded in a tight sleeve layer matrix through an ion exchange method.

Description

Technical Field

[0001] The invention belongs to the technical field of optical fibers, and in particular relates to a high-strength flame-retardant optical cable material, an optical cable and a preparation method thereof. Background Art

[0002] Optical cable is a communication cable assembly that uses one or more optical fibers as transmission media and can be used individually or in groups. Self-supporting optical cable means that the optical cable's own reinforcement components can withstand its own weight and external loads. Because it is self-supporting, its mechanical strength is very important. When the existing 8-shaped self-supporting optical cable is installed and used, the optical cable is shaped like an 8. When the optical cable is bent during use, it may break. If the optical cable breaks, the upper and lower layers of the optical cable may separate, affecting the normal use of the optical cable, which has brought certain adverse effects on people's use process. At present, the rapid development of fiber-to-the-home technology has led to the rapid expansion of the scale of the indoor optical cable industry. In addition to traditional operators, indoor optical cable products are also developing rapidly in non-operator markets such as communication supporting equipment manufacturers, military and sensor products. During the use of tight-buffered optical fiber products, the tight-buffered layer must be stripped. In order to ensure the quality of the tight-buffered optical fiber and facilitate use, the stripping force of the tight-buffered layer of the tight-buffered optical fiber must be controlled within a certain range.

[0003] A Chinese patent with announcement number CN109491031B announces a tight-jacketed optical fiber and a method for manufacturing a tight-jacketed optical fiber. A separation layer is arranged between the optical fiber body and the tight-jacketed layer. The separation layer is made of a special material, polybutadiene acrylic copolymer, so that the tight-jacketed layer is easy to separate and slide relative to the optical fiber body, reducing the peeling force. The components of the tight-jacketed layer include thermoplastic polyester elastomer or nylon. The separation layer and the tight-jacketed layer have poor thermal conductivity, resulting in low heat transfer efficiency inside the material. The optical fiber is in a high temperature state for a long time, resulting in a decrease in the performance of the optical fiber. Summary of the invention

[0004] The purpose of the present invention is to provide a high-strength flame-retardant optical cable material. A zinc skeleton is generated in situ on the surface of nano-magnesium oxide powder and carbon fiber through hydroxylation treatment. A large number of amino groups on the surface of the zinc skeleton are combined with the cyanide groups of the side chains of nitrile rubber. The nano-magnesium oxide powder and carbon fiber are dispersed in a ceramic rubber composite powder. The nano-magnesium oxide and carbon fiber can significantly improve the overall strength and thermal conductivity of the tight sheath layer of the optical cable.

[0005] The purpose of the present invention can be achieved by the following technical solutions: A method for preparing a high-strength flame-retardant optical cable material and an optical cable, comprising the following steps: Step 1: Add fluorinated modified polyurethane, ceramic rubber composite powder, ammonium polyphosphate, stearic acid and 60-70% ethanol solution into a reactor, stir at 50-60°C and 400-500r / min for 30-40min under a nitrogen atmosphere, heat to 80-90°C, continue stirring and reacting for 4-5h, heat to 180-190°C and stir at 400-500r / min for 30-40min, send into a twin-screw extruder with a length-to-diameter ratio of 36:1 for extrusion granulation, and the extruder speed is 90-120r / min to obtain a high-strength flame-retardant optical cable material.

[0006] Step 2: The obtained high-strength flame-retardant optical cable material is used as the tight jacket layer in the optical fiber, and the PVC resin is used as the spacer layer in a mass ratio of 1:1.5 with the cable core using a non-cross-linked three-layer co-extrusion technology, the temperature is 200°C, and segmented and step-by-step cooling is used to prepare a high-strength flame-retardant optical cable.

[0007] Further, the fluorinated modified polyurethane is prepared by the following steps: Isocyanate, polyether polyol, deionized water and 0.3-0.5% dibutyltin dilaurate solution were added into the reactor, stirred at 70-80°C and 500-600r / min for 1-2h to obtain polyurethane, which was then transferred into the DBD reactor and sealed under vacuum to maintain the pressure in the reactor at 2.0×10 -3 -2.8×10 -3 Pa, introduce carbon tetrafluoride and nitrogen with a volume ratio of 20:1 into the reactor, with nitrogen as the protective gas, so that the internal pressure is increased to 8-10Kpa, evacuate, introduce carbon tetrafluoride and nitrogen into the reactor again until the internal pressure is stabilized at 12.5-13.5Kpa, set the applied voltage to 22-24kV, the frequency to 8-9kHz, discharge for 30-40min, filter, wash the filter cake with deionized water 2-3 times, and vacuum dry at 60-80℃ for 1-2h to obtain fluorinated polyurethane, transfer to a reactor containing ammonia water and ethylene glycol with a mass fraction of 50-60%, stir at 80-90℃ and 500-600r / min for 2-3h, filter, wash the filter cake with deionized water and anhydrous ethanol respectively 2-3 times, and vacuum dry at 60-80℃ for 1-2h to obtain fluorinated modified polyurethane.

[0008] Furthermore, the ceramic rubber composite powder is prepared by the following steps: The nitrile rubber powder and chlorobenzene are mixed into a nitrile rubber liquid with a mass fraction of 7-8%. The nitrile rubber liquid and deionized water are added into a reactor, stirred for 40-60 minutes at 20-25°C and 500-600r / min, nitrogen and hydrogen are filled and discharged three times and three times respectively, and finally hydrogen is filled to a pressure of 3-4MPa, and heated to 50-60°C. The hydrogen outside the reactor is detected with a gas detector to ensure that there is no gas leakage. The stirring reaction is continued for 4-5 hours, and the modified composite powder is added into the reactor, and the stirring is continued for 4-5 hours. The reaction is naturally cooled and filtered. The filter cake is washed with deionized water for 2-3 times, vacuum dried at 60-80°C for 1-2 hours, and crushed to obtain a ceramic rubber composite powder with a particle size of 200-300μm.

[0009] Further, the modified composite powder is prepared by the following steps: Nano magnesium oxide powder with a particle size of 18-20 nm, carbon fiber with a length of 1-2 mm and anhydrous ethanol are added to a reactor, stirred at 20-25° C. and 500-600 r / min for 40-60 min, potassium hydroxide is added to the reactor, ultrasonically vibrated for 40-60 min, taken out and placed in an oil bath at 70-90° C. for reflux reaction for 8-12 h, filtered, and the filter cake is washed with deionized water and anhydrous ethanol until the pH is 6.5-7.5, and vacuum dried at 60-80° C. for 1-2 h to obtain a carbon fiber ceramic composite. composite powder; adding carbon fiber ceramic composite powder, 2-aminoterephthalic acid and deionized water into a reactor, dissolving sodium hexadecyl sulfate as a surfactant in an ethanol solution with a mass fraction of 60-70% and then adding the solution into the reactor, stirring for 30-40 minutes at 80-90° C. and 400-500 r / min, adding zinc sulfate into the reactor, continuing to stir the reaction for 3-4 hours, cooling naturally, filtering, washing the filter cake with deionized water for 2-3 times, and vacuum drying at 60-80° C. for 1-2 hours to obtain a modified composite powder.

[0010] Furthermore, in step 1, the usage ratio of fluorinated modified polyurethane, ceramic rubber composite powder, ammonium polyphosphate, stearic acid and ethanol is 2-3kg: 400-500g: 800-900g: 100-200g: 4-5L.

[0011] Furthermore, the usage ratio of nano magnesium oxide powder, carbon fiber, anhydrous ethanol and potassium hydroxide is 2-3kg: 1-2kg: 7-8L: 500-600g.

[0012] Furthermore, the usage ratio of carbon fiber ceramic composite powder, 2-aminoterephthalic acid, deionized water, sodium hexadecyl sulfate, ethanol and zinc sulfate is 1-2kg: 3-4kg: 2-3L: 800-900g: 1-2L: 1-2kg.

[0013] Furthermore, the usage ratio of nitrile rubber powder and chlorobenzene is 5-6kg:8-9L.

[0014] Furthermore, the usage ratio of the nitrile rubber liquid, deionized water and the modified composite powder is 1-2L:2-3L:1-2kg.

[0015] Furthermore, the usage ratio of isocyanate, polyether polyol, deionized water, dibutyltin dilaurate, ammonia water and ethylene glycol is 1-2L: 1.5-2.5L: 6-8L: 200-300mL: 1-2L: 500-600mL.

[0016] Beneficial effects of the present invention: 1. A high-strength flame-retardant optical cable prepared by the present invention has excellent flame-retardant effect, moisture-proof and anti-corrosion capabilities, and can significantly improve the bending resistance of the optical cable when used as the tight sleeve layer of the optical cable; the ceramic rubber composite powder of the present invention is treated by hydroxylation of nano-magnesium oxide powder and carbon fiber to generate a zinc skeleton in situ on the surface, and a large number of amino groups on the surface of the zinc skeleton are combined with the cyano group (-C≡N) of the side chain of the nitrile rubber, so that the modified composite powder can be evenly and stably dispersed in the ceramic rubber composite powder, and the nano-magnesium oxide and carbon fiber can significantly improve the overall strength and thermal conductivity of the tight sleeve layer of the optical cable, and the zinc skeleton generated on the surface can further improve the overall strength; when the nitrile rubber undergoes a hydrogenation reaction, the double bond groups on the molecular chain will undergo selective hydrogenation reduction to become saturated bonds. In this process, the zinc ions in the center of the zinc skeleton on the surface play a stable catalytic role, and the hydrogenated nitrile rubber can significantly increase the heat resistance and aging resistance.

[0017] 2. The fluorinated modified polyurethane of the present invention can break and reorganize the chemical bonds of the polyurethane by utilizing the plasma fluorination technology and the fluorinated gas in the plasma state, thereby realizing the fluorination modification of the polyurethane. The surface of the obtained tight-fitting layer matrix contains a large number of fluorine atoms, and the fluorine atoms have extremely strong electronegativity and chemical stability, so that the tight-fitting layer matrix can resist the erosion of water and other chemical substances, and improve the anti-corrosion performance. In addition, the molecular chain structure of the polyurethane after fluorination is compact and not easily penetrated by water molecules, thereby further enhancing its moisture-proof performance. The fluorinated polyurethane is placed in ammonia water to obtain a fluorinated modified polyurethane containing a large number of amino groups on the surface. The amino groups on the surface of the fluorinated modified polyurethane are ion-exchanged with the ammonium groups of ammonium polyphosphate, so that the ammonium polyphosphate can be effectively loaded in the tight-fitting layer matrix, and the flame retardant ability is significantly increased. DETAILED DESCRIPTION

[0018] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] Embodiment 1: A method for preparing a high-strength flame-retardant optical cable material and an optical cable, which is prepared by the following steps: S1: 2kg of nano magnesium oxide powder with a particle size of 18-20nm, 1kg of carbon fiber with a length of 1-2mm and 7L of anhydrous ethanol were added to a reactor, stirred at 20℃ and 500r / min for 40min, 500g of potassium hydroxide was added to the reactor, ultrasonically vibrated for 40min, taken out and placed in a 70℃ oil bath for reflux reaction for 8h, filtered, and the filter cake was washed with deionized water and anhydrous ethanol to a pH of 6.5, and vacuum dried at 60℃ for 1h to obtain a carbon fiber ceramic composite powder; 1kg of carbon fiber ceramic composite powder, 3kg 2-Aminoterephthalic acid and 2L of deionized water were added to the reactor, 800g of sodium hexadecyl sulfate as a surfactant was dissolved in 1L of 60% ethanol solution and added to the reactor, stirred at 80°C and 400r / min for 30min, 1kg of zinc sulfate was added to the reactor, and the stirring reaction was continued for 3h, naturally cooled, filtered, and the filter cake was washed twice with deionized water and dried in vacuo at 60°C for 1h to obtain a modified composite powder.

[0020] Nano-magnesium oxide powder and carbon fiber are treated by hydroxylation to generate a zinc skeleton in situ on the surface. The large number of amino groups on the surface of the zinc skeleton can combine with the unhydrogenated side chain cyanide (-C≡N) of the acrylonitrile unit after the hydrogenation reaction of nitrile rubber, so that the modified composite powder can be evenly and stably dispersed in the ceramic rubber composite powder. The modified composite powder has good thermal conductivity and flame retardancy, and can significantly increase the overall strength of the tight jacket layer.

[0021] S2: 5 kg of nitrile rubber powder and 8 L of chlorobenzene were mixed into a nitrile rubber liquid with a mass fraction of 7%. 1 L of nitrile rubber liquid and 2 L of deionized water were added into the reactor. The mixture was stirred at 20 °C and 500 r / min for 40 min. Nitrogen and hydrogen were filled and discharged three times and three times respectively. Finally, hydrogen was filled to a pressure of 3 MPa. The mixture was heated to 50 °C. The hydrogen outside the reactor was detected with a gas detector to ensure that there was no gas leakage. The reaction was continued to be stirred for 4 h. 1 kg of modified composite powder was added into the reactor. The mixture was continued to be stirred for 4 h. The mixture was naturally cooled and filtered. The filter cake was washed with deionized water twice, dried under vacuum at 60 °C for 1 h, and crushed to obtain a ceramic rubber composite powder with a particle size of 200-300 μm.

[0022] After dissolving nitrile rubber in chlorobenzene, the cyanide group in the nitrile rubber combines with the amino group on the zinc skeleton, and then undergoes a hydrogenation reaction. The double bond groups on the nitrile rubber molecular chain undergo selective hydrogenation reduction to become saturated bonds. In this process, the zinc ions in the center of the zinc skeleton on the surface play a stable catalytic role. The hydrogenated nitrile rubber can significantly increase its heat resistance and aging resistance.

[0023] S3: 1L isocyanate, 1.5L polyether polyol, 6L deionized water and 200mL 0.3% dibutyltin dilaurate solution were added into the reactor, stirred at 70°C and 500r / min for 1h to obtain polyurethane, which was then transferred to the DBD reactor and sealed under vacuum to maintain the pressure in the reactor at 2.8×10 -3 Pa, carbon tetrafluoride and nitrogen with a volume ratio of 20:1 are introduced into the reactor, with nitrogen as the protective gas, so that the internal pressure is increased to 8Kpa, and vacuum is drawn. Carbon tetrafluoride and nitrogen are introduced into the reactor again until the internal pressure is stabilized at 12.5Kpa, and the applied voltage is set to 22kV and the frequency is 8kHz. The discharge is carried out for 30min, and the filter cake is washed with deionized water twice, and vacuum dried at 60℃ for 1h to obtain fluorinated polyurethane, which is transferred to a reactor containing 1L of 50% ammonia water by mass and 500mL of ethylene glycol, and stirred at 80℃ and 500r / min for 2h, filtered, and the filter cake is washed with deionized water and anhydrous ethanol twice respectively, and vacuum dried at 60℃ for 1h to obtain fluorinated modified polyurethane.

[0024] The plasma fluorination technology utilizes fluorine-containing gas in a plasma state to break and reorganize the chemical bonds of polyurethane, thereby achieving fluorination modification of polyurethane; the fluorinated polyurethane is placed in ammonia water to obtain a fluorinated modified polyurethane containing a large number of amino groups on the surface.

[0025] S4: 2kg of fluorinated modified polyurethane, 400g of ceramic rubber composite powder, 800g of ammonium polyphosphate, 100g of stearic acid and 4L of 60% ethanol solution were added into a reactor, stirred at 50°C and 400r / min for 30min under a nitrogen atmosphere, heated to 80°C, continued to stir for 4-5h, heated to 180°C and stirred at 400r / min for 30min, and sent into a twin-screw extruder with a length-to-diameter ratio of 36:1 for extrusion and granulation. The extruder speed was 90r / min to obtain a high-strength flame-retardant optical cable material.

[0026] The amino groups on the surface of the fluorinated modified polyurethane undergo ion exchange with the ammonium groups of ammonium polyphosphate, so that the ammonium polyphosphate can be effectively dispersed in the tight-fitting layer matrix, significantly increasing the flame retardancy; the surface of the obtained tight-fitting layer matrix contains a large number of fluorine atoms, which have extremely strong electronegativity and chemical stability, so that the tight-fitting layer matrix can resist corrosion from moisture and other chemicals. In addition, the molecular chain structure of the fluorinated polyurethane is tight and is not easily penetrated by moisture molecules, thereby further enhancing its moisture-proof performance.

[0027] S5: The obtained high-strength flame-retardant optical cable material is used as the tight jacket layer in the optical fiber, and the PVC resin is used as the spacer layer in a mass ratio of 1:1.5 with the cable core using a non-cross-linked three-layer co-extrusion technology, the temperature is 200°C, and segmented and step-by-step cooling is used to prepare a high-strength flame-retardant optical cable.

[0028] Embodiment 2: A method for preparing a high-strength flame-retardant optical cable material and an optical cable, prepared by the following steps: S1: 2.5 kg of nano magnesium oxide powder with a particle size of 18-20 nm, 1.5 kg of carbon fiber with a length of 1-2 mm and 7.5 L of anhydrous ethanol were added to a reactor, stirred at 23 ° C and 550 r / min for 50 min, 550 g of potassium hydroxide was added to the reactor, ultrasonically vibrated for 50 min, taken out and placed in an 80 ° C oil bath for reflux reaction for 11 h, filtered, and the filter cake was washed with deionized water and anhydrous ethanol to pH 7, and vacuum dried at 70 ° C for 1.5 h to obtain a carbon fiber ceramic composite powder; 1.5 kg of carbon fiber ceramic composite powder, 3.5 kg 2-Aminoterephthalic acid and 2.5L deionized water were added to the reactor, 850g of sodium hexadecyl sulfate as a surfactant was dissolved in 1.5L of 65% ethanol solution and added to the reactor, stirred at 85°C and 450r / min for 35min, 1.5kg of zinc sulfate was added to the reactor, and the stirring reaction was continued for 3.5h, naturally cooled, filtered, and the filter cake was washed twice with deionized water and vacuum dried at 70°C for 1.5h to obtain a modified composite powder.

[0029] S2: 5.5 kg of nitrile rubber powder and 8.5 L of chlorobenzene were mixed into a nitrile rubber liquid with a mass fraction of 7.5%. 1.5 L of nitrile rubber liquid and 2.5 L of deionized water were added into the reactor. The mixture was stirred at 23 °C and 550 r / min for 50 min. Nitrogen and hydrogen were filled and discharged three times and three times respectively. Finally, hydrogen was filled to a pressure of 3.4 MPa. The mixture was heated to 55 °C. The hydrogen outside the reactor was detected with a gas detector to ensure that there was no gas leakage. The reaction was continued to be stirred for 4.5 h. 1.2 kg of modified composite powder was added into the reactor. The mixture was continued to be stirred for 4.5 h. The mixture was naturally cooled and filtered. The filter cake was washed with deionized water twice, dried under vacuum at 70 °C for 1.2 h, and crushed to obtain a ceramic rubber composite powder with a particle size of 200-300 μm.

[0030] S3: 1.2L isocyanate, 2L polyether polyol, 7L deionized water and 250mL 0.4% dibutyltin dilaurate solution were added into the reactor, stirred at 75°C and 550r / min for 1.2h to obtain polyurethane, which was then transferred into the DBD reactor and sealed under vacuum to maintain the pressure in the reactor at 2.5×10 -3 Pa, carbon tetrafluoride and nitrogen with a volume ratio of 20:1 were introduced into the reactor, with nitrogen as the protective gas, so that the internal pressure was increased to 9Kpa, and vacuum was drawn. Carbon tetrafluoride and nitrogen were introduced into the reactor again until the internal pressure was stabilized at 13Kpa, and the applied voltage was set to 23kV and the frequency to 8.5kHz. The discharge was carried out for 35min, and the filter cake was washed with deionized water twice, and vacuum dried at 70℃ for 1.5h to obtain fluorinated polyurethane, which was transferred to a reactor containing 1.5L ammonia water with a mass fraction of 55% and 550mL ethylene glycol, and stirred at 85℃ and 550r / min for 2.5h, and filtered. The filter cake was washed with deionized water and anhydrous ethanol twice respectively, and vacuum dried at 70℃ for 1.5h to obtain fluorinated modified polyurethane.

[0031] S4: 2.3 kg of fluorinated modified polyurethane, 450 g of ceramic rubber composite powder, 850 g of ammonium polyphosphate, 150 g of stearic acid and 4.5 L of 65% ethanol solution were added into a reactor, stirred at 55 ° C and 450 r / min for 35 min under a nitrogen atmosphere, heated to 85 ° C, continued to stir and react for 4.5 h, heated to 185 ° C and stirred at 450 r / min for 35 min, and sent into a twin-screw extruder with a length-to-diameter ratio of 36:1 for extrusion and granulation. The extruder speed was 100 r / min to obtain a high-strength flame-retardant optical cable material.

[0032] S5: The obtained high-strength flame-retardant optical cable material is used as the tight jacket layer in the optical fiber, and the PVC resin is used as the spacer layer in a mass ratio of 1:1.5 with the cable core using a non-cross-linked three-layer co-extrusion technology, the temperature is 200°C, and segmented and step-by-step cooling is used to prepare a high-strength flame-retardant optical cable.

[0033] Embodiment 3: A method for preparing a high-strength flame-retardant optical cable material and an optical cable, prepared by the following steps: S1: 3 kg of nano magnesium oxide powder with a particle size of 20 nm, 2 kg of carbon fiber with a length of 2 mm and 8 L of anhydrous ethanol were added to a reactor, stirred at 25 ° C and 600 r / min for 60 min, 600 g of potassium hydroxide was added to the reactor, ultrasonically vibrated for 60 min, taken out and placed in a 90 ° C oil bath for reflux reaction for 12 h, filtered, and the filter cake was washed with deionized water and anhydrous ethanol to a pH of 7.5, and vacuum dried at 80 ° C for 2 h to obtain a carbon fiber ceramic composite powder; 2 4kg carbon fiber ceramic composite powder, 4kg2-aminoterephthalic acid and 3L deionized water were added into the reactor, 900g sodium hexadecyl sulfate as a surfactant was dissolved in 2L 70% ethanol solution and added into the reactor, stirred at 90°C and 500r / min for 40min, 2kg zinc sulfate was added into the reactor, the stirring reaction was continued for 4h, naturally cooled and filtered, the filter cake was washed 3 times with deionized water and dried in vacuo at 80°C for 2h to obtain modified composite powder.

[0034] S2: 6 kg of nitrile rubber powder and 9 L of chlorobenzene were mixed into 8% mass fraction of nitrile rubber liquid, 2 L of nitrile rubber liquid and 3 L of deionized water were added into the reactor, stirred at 25 ° C and 600 r / min for 60 min, nitrogen and hydrogen were filled and discharged three times and three times respectively, and finally hydrogen was filled to a pressure of 4 MPa, heated to 60 ° C, and the hydrogen outside the reactor was detected with a gas detector to ensure that there was no gas leakage. The stirring reaction was continued for 5 h, 2 kg of modified composite powder was added into the reactor, stirring was continued for 5 h, naturally cooled, filtered, the filter cake was washed with deionized water for 3 times, vacuum dried at 80 ° C for 2 h, and crushed to obtain a ceramic rubber composite powder with a particle size of 200-300 μm.

[0035] S3: 2L of isocyanate, 2.5L of polyether polyol, 8L of deionized water and 300mL of 0.5% dibutyltin dilaurate solution were added into the reactor, stirred and reacted at 80°C and 600r / min for 2h to obtain polyurethane, which was then transferred to the DBD reactor and sealed under vacuum to maintain the pressure in the reactor at 2.8×10 -3Pa, carbon tetrafluoride and nitrogen with a volume ratio of 20:1 are introduced into the reactor, with nitrogen as the protective gas, so that the internal pressure is increased to 10Kpa, and vacuum is drawn. Carbon tetrafluoride and nitrogen are introduced into the reactor again until the internal pressure is stabilized at 13.5Kpa, and the applied voltage is set to 24kV and the frequency is 9kHz. The discharge is carried out for 40min, and the filter cake is washed with deionized water for 3 times, and vacuum dried at 80℃ for 2h to obtain fluorinated polyurethane, which is transferred to a reactor containing 2L of ammonia water with a mass fraction of 60% and 600mL of ethylene glycol, and stirred at 90℃ and 600r / min for 3h, and filtered. The filter cake is washed with deionized water and anhydrous ethanol for 3 times respectively, and vacuum dried at 80℃ for 2h to obtain fluorinated modified polyurethane.

[0036] S4: 3kg of fluorinated modified polyurethane, 500g of ceramic rubber composite powder, 900g of ammonium polyphosphate, 200g of stearic acid and 5L of 70% ethanol solution were added into a reactor, stirred at 60°C and 500r / min for 40min under a nitrogen atmosphere, heated to 90°C, continued to stir for 5h, heated to 190°C and stirred at 500r / min for 40min, and sent into a twin-screw extruder with a length-to-diameter ratio of 36:1 for extrusion and granulation. The extruder speed was 120r / min to obtain a high-strength flame-retardant optical cable material.

[0037] S5: The obtained high-strength flame-retardant optical cable material is used as the tight jacket layer in the optical fiber, and the PVC resin is used as the spacer layer in a mass ratio of 1:1.5 with the cable core using a non-cross-linked three-layer co-extrusion technology, the temperature is 200°C, and segmented and step-by-step cooling is used to prepare a high-strength flame-retardant optical cable.

[0038] Comparative Example 1: Based on Example 3, the modified composite powder in step S2 is replaced by the carbon fiber ceramic composite powder in step S1, and the other steps remain unchanged to prepare a high-strength flame-retardant optical cable.

[0039] Comparative Example 2: Based on Example 3, the fluorinated modified polyurethane in step S4 is replaced by the polyurethane in step S3, and the other steps remain unchanged to prepare a high-strength flame-retardant optical cable.

[0040] Comparative Example 3: Based on Example 3, the fluorinated modified polyurethane in step S4 is replaced by the fluorinated polyurethane in step S3, and the other steps remain unchanged to prepare a high-strength flame-retardant optical cable.

[0041] In the embodiments and comparative examples: Nano-magnesium oxide powder, carbon fiber, 2-aminoterephthalic acid, sodium hexadecyl sulfate, nitrile rubber powder, chlorobenzene, isocyanate, and polyether polyol were purchased from Sigma-Aldrich.

[0042] The performance of a high-strength flame-retardant optical cable prepared by Example 1 to Example 3 and Comparative Example 1 to Comparative Example 3 was tested, and the results are shown in Table 1: 1. Elongation at break: Refer to GB / T 2951.11-2008 "General test methods for insulation and sheathing materials of electric and optical cables Part 11: General test methods for thickness and dimensional measurement - Mechanical properties test" for the standard test elongation at break; 2. Oxygen index test: Refer to GB / T 18380.11-2022 "Combustion test of electric cables and optical cables under flame conditions Part 11: Test apparatus for vertical flame spread test of single insulated wires and cables" for single vertical combustion test; refer to GB / T 2406.2-2009 "Determination of combustion behavior of plastics by oxygen index method Part 2: Room temperature test" for oxygen index test; 3. Impact strength: Use the national standard GBT9330.2-2008 to conduct impact strength test; 4. Thermal conductivity: Use a thermal conductivity tester to test the thermal conductivity of the sample; 5. Water contact angle: The measuring instrument is SZ-CAMB3 measuring instrument of Shanghai Xuanzhun Instrument Co., Ltd., and the high-strength flame-retardant optical cable material is pressed into sheets under a pressure of 10MPa using an infrared sheeting mold. The average value is taken after three tests at different positions to evaluate the moisture-proof ability of different samples. Table 1 Performance test table of a high-strength flame-retardant optical cable project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Thermal conductivity W / (mK) 2.8 2.8 2.9 1.8 2.8 2.8 Elongation at break (%) 349 354 357 335 350 351 Oxygen index (%) 32 33 34 33 32 15 Impact strength (MPa) 10.8 10.9 11.2 9.4 11.1 10.8 Water contact angle (°) 86 88 90 88 45 88 It can be seen from Table 1 that the thermal conductivity, elongation at break, oxygen index, impact strength and water contact angle of the high-strength flame-retardant optical cable prepared by the present invention are significantly better than those of the comparative example, indicating that the high-strength flame-retardant optical cable of the present invention has excellent thermal conductivity, high strength, bending resistance, flame retardancy and moisture resistance.

[0043] In Comparative Example 1, the modified composite powder is replaced with carbon fiber ceramic composite powder, and the nano-magnesium oxide and carbon fiber cannot be evenly dispersed in the modified composite powder through the zinc skeleton, resulting in poor compatibility. In addition, the zinc skeleton can catalyze the hydrogenation reaction of nitrile rubber and improve the overall performance of nitrile rubber, thereby affecting thermal conductivity, bending resistance and impact strength.

[0044] In Comparative Example 2, the fluorinated modified polyurethane is replaced with polyurethane, and the plasma fluorine-containing gas is used to break and reorganize the chemical bonds of the polyurethane to achieve fluorination modification of the polyurethane. The fluorine atom has extremely strong electronegativity and chemical stability, so that the tight-fitting layer matrix can resist the erosion of moisture and other chemicals. The fluorinated polyurethane has a tight molecular chain structure and is not easily penetrated by moisture molecules, thereby further enhancing its moisture-proof performance. Therefore, the water contact angle is significantly reduced, and other properties are not significantly affected.

[0045] In Comparative Example 3, the fluorinated modified polyurethane is replaced with fluorinated polyurethane. The amino groups on the surface of the fluorinated modified polyurethane can undergo ion exchange with the ammonium groups of ammonium polyphosphate, so that the ammonium polyphosphate can be effectively dispersed in the tight-fitting layer matrix, significantly increasing the flame retardancy, significantly reducing the oxygen index, and having no significant effect on other properties.

[0046] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0047] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A high-strength flame-retardant optical cable material, characterized in that: Prepared by the following steps: Fluorinated modified polyurethane, ceramic rubber composite powder, ammonium polyphosphate, stearic acid and 60-70wt% ethanol solution are added into a reaction kettle, stirred at 50-60°C and 400-500r / min for 30-40min under a nitrogen atmosphere, heated to 80-90°C, stirred for 4-5h, heated to 180-190°C and 400-500r / min for 30-40min, and sent into a twin-screw extruder with a length-to-diameter ratio of 36:1 for extrusion and granulation, and the extruder speed is 90-120r / min to obtain a high-strength flame-retardant optical cable material.

2. The high-strength flame-retardant optical cable material according to claim 1, characterized in that: The usage ratio of the fluorinated modified polyurethane, ceramic rubber composite powder, ammonium polyphosphate, stearic acid and ethanol in step 1 is 2-3kg: 400-500g: 800-900g: 100-200g: 4-5L.

3. A high-strength flame-retardant optical cable material according to claim 1, characterized in that: The fluorinated modified polyurethane described in step 1 is prepared by the following steps: Isocyanate, polyether polyol, deionized water and 0.3-0.5wt% dibutyltin dilaurate solution were added into the reactor, stirred at 70-80℃ and 500-600r / min for 1-2h to obtain polyurethane, which was then transferred into the DBD reactor and sealed under vacuum to maintain the pressure at 2.0×10 -3 -2.8×10 -3 Pa, introduce carbon tetrafluoride and nitrogen with a volume ratio of 20:1 into the reactor, with nitrogen as the protective gas, so that the internal pressure is increased to 8-10Kpa, evacuate, introduce carbon tetrafluoride and nitrogen into the reactor again until the internal pressure is stabilized at 12.5-13.5Kpa, set the applied voltage to 22-24kV, the frequency to 8-9kHz, discharge for 30-40min, filter, wash the filter cake with deionized water for 2-3 times, vacuum dry to obtain fluorinated polyurethane, transfer to a reactor containing 50-60wt% ammonia water and ethylene glycol, stir at 80-90℃ and 500-600r / min for 2-3h, filter, wash the filter cake with deionized water and anhydrous ethanol for 2-3 times, vacuum dry to obtain fluorinated modified polyurethane.

4. A high-strength flame-retardant optical cable material according to claim 3, characterized in that: The usage ratio of the isocyanate, the polyether polyol, the deionized water, the dibutyltin dilaurate, the ammonia water and the ethylene glycol is 1-2L: 1.5-2.5L: 6-8L: 200-300mL: 1-2L: 500-600mL.

5. The high-strength flame-retardant optical cable material according to claim 1, characterized in that: The ceramic rubber composite powder in step 1 is prepared by the following steps: The nitrile rubber powder and chlorobenzene are mixed into 7-8wt% nitrile rubber liquid, the nitrile rubber liquid and deionized water are added into a reactor, stirred at 20-25°C and 500-600r / min for 40-60min, nitrogen and hydrogen are filled and discharged three times respectively, and finally hydrogen is filled to a pressure of 3-4MPa, heated to 50-60°C, hydrogen outside the reactor is detected with a gas detector, stirring and reacting for 4-5h, the modified composite powder is added into the reactor, stirring is continued for 4-5h, naturally cooled, filtered, the filter cake is washed with deionized water for 2-3 times, vacuum dried, and crushed to obtain a ceramic rubber composite powder with a particle size of 200-300μm; The usage ratio of the nitrile rubber powder and chlorobenzene is 5-6kg:8-9L; the usage ratio of the nitrile rubber liquid, deionized water and modified composite powder is 1-2L:2-3L:1-2kg.

6. A high-strength flame-retardant optical cable material according to claim 5, characterized in that: The modified composite powder is prepared by the following steps: Add carbon fiber ceramic composite powder, 2-aminoterephthalic acid and deionized water into a reactor, dissolve sodium hexadecyl sulfate in 60-70wt% ethanol solution and add into the reactor, stir at 80-90°C and 400-500r / min for 30-40min, add zinc sulfate into the reactor, continue stirring and reacting for 3-4h, cool naturally, filter, wash the filter cake with deionized water for 2-3 times, and vacuum dry to obtain modified composite powder.

7. A high-strength flame-retardant optical cable material according to claim 6, characterized in that: The usage ratio of the carbon fiber ceramic composite powder, 2-aminoterephthalic acid, deionized water, sodium hexadecyl sulfate, ethanol and zinc sulfate is 1-2kg: 3-4kg: 2-3L: 800-900g: 1-2L: 1-2kg.

8. The high-strength flame-retardant optical cable material according to claim 6, characterized in that: The carbon fiber ceramic composite powder is prepared by the following steps: Add nano magnesium oxide powder with a particle size of 18-20 nm, carbon fiber with a length of 1-2 mm and anhydrous ethanol into a reactor, stir at 20-25° C. and 500-600 r / min for 40-60 min, add potassium hydroxide into the reactor, ultrasonically vibrate for 40-60 min, reflux in an oil bath at 70-90° C. for 8-12 h, filter, wash the filter cake with deionized water and anhydrous ethanol until the pH is 6.5-7.5, and vacuum dry to obtain a carbon fiber ceramic composite powder; The usage ratio of the nano magnesium oxide powder, carbon fiber, anhydrous ethanol and potassium hydroxide is 2-3kg: 1-2kg: 7-8L: 500-600g.

9. An optical cable made of the high-strength flame-retardant optical cable material according to any one of claims 1 to 8.

10. The method for preparing an optical cable according to claim 8, characterized in that: The steps include: A high-strength flame-retardant optical cable material is used as the tight jacket layer in the optical fiber, and PVC resin is used as the spacer layer in a mass ratio of 1:1.5 with the cable core using a non-cross-linked three-layer co-extrusion technology at a temperature of 200°C and segmented and step-by-step cooling to prepare a high-strength flame-retardant optical cable.