Fireproof flame-retardant insulating outer sheath for cable and optical cable and preparation method of fireproof flame-retardant insulating outer sheath

Abstract

The invention relates to the technical field of cable materials, and provides a fireproof flame-retardant insulating outer sheath for cables and optical cables and a preparation method of the fireproof flame-retardant insulating outer sheath. The invention discloses a fireproof flame-retardant insulating outer sheath for cables and optical cables. The fireproof flame-retardant insulating outer sheath comprises the following raw materials in parts by weight: 30-50 parts of polyethylene, 0.5-1.5 parts of an antioxidant, 8-10 parts of a filler, 0.5-1 part of a plasticizer and 40-50 parts of a flame-retardant insulating material, the flame-retardant insulating material is composed of fireproof Bundy, alumina fibers and basalt fibers, and the mass ratio of the fireproof Bundy to the basalt fibers to the alumina fibers is 4: 3: (2-3). According to the technical scheme, the problems of low fireproof and flame-retardant performance and poor insulating performance of the existing cable and optical cable are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of cable materials, and in particular to a fire-retardant insulating outer sheath of an electric cable and an optical cable and a preparation method thereof. Background Art

[0002] Grid cables and optical cables play a vital role in modern society. They are the infrastructure for power transmission and communication. However, the vulnerability of these facilities in fires has also aroused widespread concern. Cable and optical cable fires not only affect the stability of electricity and communications, but also directly threaten the safety of life and property. Therefore, the development of an outer sheath with high fire retardant and flame retardant insulation performance must not only ensure that it has excellent use functions in terms of fire prevention, flame retardancy and insulation, effectively resist fire hazards, prevent current leakage, and comprehensively protect equipment and personnel safety, but also fully consider the convenience in practical applications, so that it is easy to assemble and can be quickly and efficiently installed on the corresponding equipment or lines, reducing installation costs and time costs, and improving overall work efficiency. Summary of the invention

[0003] The invention provides a fire-retardant insulating outer sheath of an electric cable and an optical cable and a preparation method thereof, which solves the problems of low fire-retardant performance and poor insulation performance of the current electric cable and the optical cable.

[0004] The technical solution of the present invention is as follows: The present invention proposes a fire-retardant insulating outer sheath of an electric cable and an optical cable, comprising the following component raw materials in parts by weight: 30 to 50 parts of polyethylene, 0.5 to 1.5 parts of an antioxidant, 8 to 10 parts of a filler, 0.5 to 1 part of a plasticizer, and 40 to 50 parts of a flame-retardant insulating material; the flame-retardant insulating material is composed of a fire-retardant bond, alumina fiber and basalt fiber, and the mass ratio of the fire-retardant bond, basalt fiber and alumina fiber is 4:3:2 to 3.

[0005] As a further technical solution, the fireproof bond is based on an affinity epoxy resin material, has super flexibility, weather resistance and fire resistance and heat insulation properties, and is purchased from Guangdong Heiwei Fireproof Technology Co., Ltd.

[0006] In the present invention, the fireproof bondi expands several times when encountering fire to form a dense protective layer. On the one hand, it quickly fills the wrapped object to isolate air and heat; on the other hand, the fireproof bondi has excellent flame retardant properties, which can prevent the burning of objects, thereby improving the fire retardant properties of the fireproof and flame retardant insulating outer sheath.

[0007] As a further technical solution, the alumina fiber consists of a first alumina fiber and a second alumina fiber, and the alumina content of the first alumina fiber and the second alumina fiber is different.

[0008] As a further technical solution, the alumina content of the first alumina fiber is 72wt%, the alumina content of the second alumina fiber is 85wt%, and the mass ratio of the first alumina fiber to the second alumina fiber is 2:2~3.

[0009] In the present invention, the first alumina fiber and the second alumina fiber with different alumina contents are added simultaneously, and the synergistic effect of the two is exerted by adjusting the mass ratio of the two to further improve the fire retardant and insulation properties of the outer sheath.

[0010] As a further technical solution, the alumina fiber is a modified alumina fiber, and the modified alumina fiber is obtained by modifying the alumina fiber with a modifier, and the modifier is an aminothiazole acid compound.

[0011] In the present invention, aminothiazole acid compounds are used to modify alumina fibers, thereby enhancing the dispersibility of the alumina fibers and the compatibility of the alumina fibers with the polyethylene matrix, and further improving the fire retardant and insulating properties of the outer sheath.

[0012] As a further technical solution, the raw material of the modifier alumina fiber includes the modifier and the alumina fiber in a mass ratio of 2 to 3:20.

[0013] As a further technical solution, the aminothiazole acid compound includes one or both of 2-aminothiazole-4-acetic acid and 2-aminothiazole-4-carboxylic acid.

[0014] As a further technical solution, the preparation method of the modifier alumina fiber includes the following steps: dispersing the modifier in a solvent, adding the alumina fiber, mixing, filtering and drying to obtain the modified alumina fiber.

[0015] As a further technical solution, the solvent is dimethyl sulfoxide.

[0016] As a further technical solution, the mass ratio of the solvent to the alumina fiber is 10:1.

[0017] As a further technical solution, the mixing time is 2 hours.

[0018] As a further technical solution, the antioxidant includes one or more of antioxidant 1010 , antioxidant 1076 , and antioxidant 330 .

[0019] As a further technical solution, the filler includes one or both of expanded perlite and expanded vermiculite.

[0020] As a further technical solution, the plasticizer includes one or more of dioctyl phthalate, dibutyl phthalate, and diisodecyl phthalate.

[0021] The present invention also provides a method for preparing a fire-retardant insulating outer sheath of an electric cable and an optical cable, comprising the following steps: weighing the component raw materials in parts by weight, mixing them evenly and then extruding them to obtain the fire-retardant insulating outer sheath.

[0022] As a further technical solution, the fire-retardant insulating outer sheath can be designed into fire-retardant insulating outer sheaths of different specifications and colors according to the diameter or composition of the electric cable or optical cable.

[0023] In the present invention, the ends of the electric cables and optical cables covered with the fireproof and flame-retardant insulating outer sheaths also need to be fireproofed and tightly packaged with fireproof zippers or fireproof drawstrings.

[0024] As a further technical solution, the specifications of the fire-retardant insulating outer sheath include 2m 2 、4m 2 One of them.

[0025] The present invention also proposes a method for preparing a cable, wherein the fire-retardant insulating outer sheath or the fire-retardant insulating outer sheath prepared by the method for preparing the fire-retardant insulating outer sheath is coated on the outside of an existing cable to obtain a cable, and the coating method can be one of adhesive tape coating, cable tie fixed coating, fire-retardant zipper coating, and fire-retardant buckle coating, and the existing cable includes one of an existing electrical cable or an existing optical cable.

[0026] As a further technical solution, temperature sensors are arranged inside and outside the fire-resistant and flame-retardant insulating outer sheath.

[0027] In the present invention, temperature sensors are arranged inside and outside the fire-retardant insulating outer sheath. The temperature sensors adopt micro-energy power extraction technology. This technology has excellent environmental adaptability and can keenly capture and make full use of various energy forms widely existing in the surrounding environment, such as vibration, heat and temperature, and convert these energies into electrical energy required for the operation of the sensor itself, fundamentally solving the problem of regular battery replacement faced by traditional temperature sensors that rely on battery power supply.

[0028] The temperature sensor in the present invention has micro-energy power supply technology. In actual application scenarios, traditional battery-powered temperature sensors are subject to the limited battery power and often require tedious battery replacement operations on a regular basis, which not only consumes a lot of manpower and material resources, but may also cause sensor failure due to untimely battery replacement, thereby affecting the stability and reliability of the entire monitoring system. The micro-energy power supply technology adopted in the present invention enables the temperature sensor to get rid of its dependence on traditional batteries, realizes autonomous power supply, greatly reduces maintenance costs and risks, and significantly improves the system's operating stability and reliability.

[0029] The temperature sensor added in the present invention can not only realize autonomous power supply, but also realize real-time and accurate monitoring of the internal temperature of the cable and optical cable in the outer sheath and the external temperature. Whether it is the internal temperature rise of the cable and optical cable caused by current transmission during operation, or the change of the external environment temperature, it can be captured in a timely and accurate manner. This all-round and real-time temperature monitoring function can quickly issue an early warning signal when the temperature shows an abnormal rising trend, which can buy precious processing time for the operation and maintenance personnel.

[0030] The temperature sensor added in the present invention also has the function of predicting when the temperature is too high. Through intelligent analysis and algorithm processing of long-term monitoring data, it can predict in advance the time point when the temperature may reach the dangerous threshold, and issue an early warning to the operation and maintenance personnel before the temperature actually reaches the dangerous limit. This forward-looking prediction capability enables the operation and maintenance personnel to take targeted preventive measures before potential faults evolve into actual accidents, thereby effectively avoiding serious accidents such as cable and optical cable damage and fire caused by excessive temperature, and ensuring the safe and stable operation of the power and communication systems.

[0031] The temperature sensor added in the present invention will accurately record the location information of each sensor during installation. When the temperature reaches the threshold and a pre-alarm is issued, the system will quickly send the location information corresponding to the temperature sensor to the operation and maintenance personnel. This design greatly improves the efficiency of troubleshooting. The operation and maintenance personnel do not need to blindly look for the fault point in the complex line layout, but can quickly locate the specific location of the temperature anomaly based on accurate location information, and conduct targeted inspections and repairs, which greatly shortens the troubleshooting time, improves the efficiency and quality of operation and maintenance work, and ensures that the power and communication systems can resume normal operation in the shortest time.

[0032] The present invention also proposes an application of a fire-resistant and flame-retardant insulating outer sheath, and the application scenarios include tunnels, wells, and trenches.

[0033] The working principle and beneficial effects of the present invention are: 1. In the present invention, polyethylene is used as a raw material, which provides good flexibility and mechanical properties, so that the outer sheath is easy to process and can withstand certain external force extrusion and stretching in actual use. The outer sheath is prepared by adding a flame-retardant insulating material, and the outer sheath is coated on the outside of the existing cable and optical cable in the form of adhesive tape, cable tie, zipper, etc. to form a fire-retardant insulating layer. The fire-retardant bondi, alumina fiber and basalt fiber in the flame-retardant insulating material play a synergistic role, which can effectively prevent the spread of flames, prevent the transfer of charges, reduce the risk of leakage, and improve the fire-retardant and flame-retardant properties and insulation properties of the outer sheath.

[0034] 2. In the present invention, the fire-retardant insulating outer sheath has an extremely important and practical dual protection function, and plays an irreplaceable role in ensuring the safety of power transmission and communication. On the one hand, from the perspective of internal protection, the fire-retardant insulating outer sheath can effectively prevent fire accidents caused by short circuits, overloads, etc. inside existing cables and optical cables, and can suppress the generation and spread of internal fire sources at the first time, and kill the hidden dangers of fire in the bud. The fire will not easily spread to the surrounding facilities, thereby avoiding the serious consequences of a chain reaction caused by a fire in one place, resulting in the surrounding equipment and facilities being damaged by fire. This is of great significance for protecting the surrounding electrical equipment, buildings and personnel safety. On the other hand, in terms of external protection, when encountering an external fire, the fire-retardant insulating outer sheath can effectively block the transfer of heat under the attack of high-temperature flames, slow down the speed of external flames to damage the internal structure of existing cables and optical cables, and ensure that the existing cables and optical cables can still maintain normal power transmission or signal transmission functions within a certain period of time. This protection not only helps ensure the basic operation of important places (such as data centers, hospitals, transportation hubs, etc.) during fires, but also buys valuable time for firefighting and rescue work, minimizes the damage caused by fire to existing cable and optical cable systems, and effectively maintains the stability and reliability of the entire power and communication network. DETAILED DESCRIPTION

[0035] 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.

[0036] In the following examples and comparative examples: First alumina fiber: alumina content is 72wt%, silica content is 28wt%; Second alumina fiber: alumina content is 85wt%, silica content is 15wt%; Polyethylene: Model 5000S; Fireproof Bondi: Model is VB, manufacturer is Guangdong Heiwei Fire Protection Technology Co., Ltd.; Basalt fiber: diameter 1.5μm, length 125μm; Expanded perlite: average particle size is 325 mesh; Expanded vermiculite: The average particle size is 325 mesh.

[0037] Example 1 A method for preparing a fire-retardant insulating outer sheath of an electric cable and an optical cable comprises the following steps: weighing 30 parts of polyethylene, 0.5 parts of antioxidant 1010, 8 parts of expanded perlite, 0.5 parts of dioctyl phthalate, and 40 parts of a flame-retardant insulating material, mixing them evenly, and then extruding them to obtain a fire-retardant insulating outer sheath, wherein the flame-retardant insulating material consists of fire-retardant bonded fiber, basalt fiber, and alumina fiber in a mass ratio of 4:3:2, and the alumina fiber is a first alumina fiber.

[0038] Example 2 A method for preparing a fire-retardant insulating outer sheath of an electric cable and an optical cable comprises the following steps: weighing 40 parts of polyethylene, 1 part of antioxidant 1076, 9 parts of expanded perlite, 0.8 parts of dibutyl phthalate, and 45 parts of a flame-retardant insulating material, mixing them evenly, and then extruding them to obtain a fire-retardant insulating outer sheath, wherein the flame-retardant insulating material consists of fire-retardant bonded fiber, basalt fiber, and alumina fiber in a mass ratio of 4:3:2, and the alumina fiber is a first alumina fiber.

[0039] Example 3 A method for preparing a fire-retardant insulating outer sheath of an electric cable and an optical cable comprises the following steps: weighing 50 parts of polyethylene, 1.5 parts of antioxidant 330, 10 parts of expanded vermiculite, 1 part of diisodecyl phthalate, and 50 parts of a flame-retardant insulating material, mixing them evenly, and then extruding them to obtain a fire-retardant insulating outer sheath, wherein the flame-retardant insulating material consists of fire-retardant bonded fiber, basalt fiber, and alumina fiber in a mass ratio of 4:3:2, and the alumina fiber is a first alumina fiber.

[0040] Example 4 Compared with Example 3, the difference of Example 4 is that the flame retardant insulating material consists of fireproof Bondi, basalt fiber and alumina fiber in a mass ratio of 4:3:3.

[0041] Example 5 Compared with Example 4, the difference in Example 5 is that the first alumina fiber is replaced by an equal amount of second alumina fiber.

[0042] Example 6 Compared with Example 4, the difference of Example 6 is that the first alumina fiber is replaced by the first alumina fiber and the second alumina fiber in a mass ratio of 1:1.

[0043] Example 7 Compared with Example 4, the difference of Example 7 is that the first alumina fiber is replaced by the first alumina fiber and the second alumina fiber in a mass ratio of 2:3.

[0044] Example 8 The preparation method of modified alumina fiber comprises the following steps: dispersing 2 parts of 2-aminothiazole-4-acetic acid in 200 parts of dimethyl sulfoxide solution, adding 20 parts of first alumina fiber and second alumina fiber with a mass ratio of 2:3, mixing for 2 hours, filtering and drying to obtain modified alumina fiber; Compared with Example 7, the difference of Example 8 is that the alumina fiber is replaced by an equal amount of modified alumina fiber obtained by the above preparation method.

[0045] Example 9 Compared with Example 8, the difference in Example 9 is that the added amount of 2-aminothiazole-4-acetic acid is 3 parts.

[0046] Example 10 Compared with Example 9, Example 10 is different in that 2-aminothiazole-4-acetic acid is replaced by an equal amount of 2-aminothiazole-4-carboxylic acid.

[0047] Comparative Example 1 Compared with Example 3, the difference of Comparative Example 1 is that the flame retardant insulating material consists of fireproof bonded fiber and basalt fiber in a mass ratio of 4:3.

[0048] Comparative Example 2 Compared with Example 3, the difference of Comparative Example 2 is that the flame retardant insulating material is alumina fiber.

[0049] The fire-retardant insulating outer sheaths prepared in Examples 1 to 10 and Comparative Examples 1 to 2 were tested according to the following method: 1. Oxygen index: According to the test method specified in GB / T 2406.2-2009 "Determination of combustion behavior of plastics by oxygen index method Part 2: Room temperature test", use the ignition method of method A to test the oxygen index of the sample.

[0050] 2. Volume resistivity: According to the test method specified in GB / T 31838.2-2019 "Dielectric and resistive properties of solid insulating materials Part 2: Resistance characteristics (DC method) Volume resistance and volume resistivity", the volume resistivity of the sample is tested. The test conditions are: 23°C and 50% relative humidity for 4 days.

[0051] The test results are shown in the following table: Table 1 Performance test results of fire-retardant insulating outer sheaths prepared in Examples 1 to 10 and Comparative Examples 1 to 2

[0052] Compared with Comparative Examples 1 and 2, Example 3 simultaneously adds fire-retardant Bondi, basalt fiber and alumina fiber as flame-retardant insulating materials. As a result, the oxygen index and volume resistivity of Example 3 are greater than those of Comparative Examples 1 and 2, indicating that the fire-retardant Bondi, basalt fiber and alumina fiber play a synergistic role in improving the fire-retardant and insulating properties of the outer sheath.

[0053] Compared with Example 4, Examples 6 and 7 simultaneously added the first alumina fiber and the second alumina fiber. As a result, the oxygen index and volume resistivity of Examples 6 and 7 were greater than those of Example 4, indicating that the first alumina fiber and the second alumina fiber played a synergistic role and could further improve the fire retardant and insulation properties of the outer sheath.

[0054] Compared with Example 7, Examples 8 to 10 added modified alumina fibers. As a result, the oxygen index and volume resistivity of Examples 8 to 10 were greater than those of Example 7, indicating that when modified alumina fibers were added, the fire retardant and insulating properties of the obtained outer sheath were better.

[0055] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A fire-retardant insulating outer sheath for electric cables and optical cables, characterized in that: The invention comprises the following raw materials in parts by weight: 30-50 parts of polyethylene, 0.5-1.5 parts of antioxidant, 8-10 parts of filler, 0.5-1 part of plasticizer and 40-50 parts of flame retardant insulating material; the flame retardant insulating material is composed of fireproofing bondi, alumina fiber and basalt fiber, and the mass ratio of the fireproofing bondi, basalt fiber and alumina fiber is 4:3:2-3.

2. A fire-retardant insulating outer sheath of an electric cable and an optical cable according to claim 1, characterized in that: The alumina fibers are composed of first alumina fibers and second alumina fibers, and the alumina contents of the first alumina fibers and the second alumina fibers are different.

3. A fire-retardant insulating outer sheath of an electric cable and an optical cable according to claim 2, characterized in that: The alumina content of the first alumina fiber is 72wt%, the alumina content of the second alumina fiber is 85wt%, and the mass ratio of the first alumina fiber to the second alumina fiber is 2:2~3.

4. The fire-retardant insulating outer sheath of an electric cable and an optical cable according to claim 1, characterized in that: The alumina fiber is a modified alumina fiber, and the modified alumina fiber is obtained by modifying the alumina fiber with a modifier, and the modifier is an aminothiazole acid compound.

5. A fire-retardant insulating outer sheath of an electric cable and an optical cable according to claim 4, characterized in that: The raw materials of the modifier alumina fiber include the modifier and the alumina fiber in a mass ratio of 2 to 3:

20.

6. A fire-retardant insulating outer sheath of an electric cable or optical cable according to claim 4, characterized in that: The aminothiazole acid compound includes one or both of 2-aminothiazole-4-acetic acid and 2-aminothiazole-4-carboxylic acid.

7. A fire-retardant insulating outer sheath of an electric cable or optical cable according to claim 1, characterized in that: It also includes at least one of the following technical features: The antioxidant includes one or more of antioxidant 1010, antioxidant 1076, and antioxidant 330; The filler includes one or two of expanded perlite and expanded vermiculite; The plasticizer includes one or more of dioctyl phthalate, dibutyl phthalate, and diisodecyl phthalate.

8. A method for preparing a fire-retardant insulating outer sheath of an electric cable or optical cable according to any one of claims 1 to 7, characterized in that: The method comprises the following steps: weighing the component raw materials in parts by weight, mixing them evenly and then extruding them to obtain a fireproof and flame-retardant insulating outer sheath.

9. A method for preparing a fire-retardant insulating outer sheath of an electric cable or optical cable according to claim 8, characterized in that: The fireproof and flame-retardant insulating outer sheath can be designed into fireproof and flame-retardant insulating outer sheaths of different specifications and colors according to the diameter or composition of the electric cable or optical cable.

10. A method for preparing a cable, comprising coating the fire-retardant insulating outer sheath described in any one of claims 1 to 7 or the fire-retardant insulating outer sheath prepared by the method for preparing the fire-retardant insulating outer sheath in claim 8 on the outside of an existing cable to obtain a cable, wherein the coating method can be one of adhesive tape coating, cable tie fixing coating, fire-retardant zipper coating, and fire-retardant buckle coating, and the existing cable comprises one of an existing electrical cable or an existing optical cable.

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