A method for manufacturing a tensile dragging optical-electric composite cable

Abstract

The invention discloses a manufacturing method of a tensile dragging photoelectric composite cable, which belongs to the field of cable processing technology. The photoelectric composite cable includes a power line, an optical fiber and a filling rope located at a core, the power line, the optical fiber and the filling rope form a cable core, the cable core is coated with a metal double-sided plastic-coated steel belt, and the outer layer of the metal double-sided plastic-coated steel belt is coated with a polyethylene outer sheath. The polyethylene outer sheath raw material of the present invention uses PE resin as a matrix, and ethylene-vinyl acetate EVA is added. EVA can not only play a toughening effect, but also play an interface enhancement effect between the polyethylene matrix and the flame retardant additive and calcium carbonate, thereby improving the comprehensive mechanical properties of the polyethylene outer sheath; in addition, the added flame retardant additive is a composite flame retardant component containing three effective elements of N, P and S; the obtained polyethylene outer sheath not only has tensile dragging ability, but also has excellent flame retardant properties, so that the composite cable can be suitable for more severe places.

Description

Technical Field

[0001] The invention belongs to the technical field of cable processing, and in particular, relates to a method for manufacturing a tensile-resistant towing optoelectronic composite cable. Background Art

[0002] Optical-electric composite cable is a new type of access method that is suitable for use as a transmission line in broadband access network systems. It integrates optical fiber and power transmission copper wire and can solve the problems of broadband access, equipment power consumption, and signal transmission. Optical-electric composite cable can achieve the effect of replacing multiple cables with one composite cable, so it has the characteristics of small outer diameter, light weight, and small space occupation. It also provides a variety of transmission technologies, high adaptability to the same equipment, strong scalability, and a wide range of product applications, with an increasingly wide range of application space.

[0003] The structure of the optical fiber composite cable is usually composed of a cable core and a sheath of a twisted structure. The sheath is mostly made of polyethylene. Polyethylene sheath material has the advantages of light weight, good insulation, and good chemical stability. However, for military vehicle cables, the tensile and drag resistance is required to be high, and ordinary polyethylene sheath material is difficult to meet the use requirements.

[0004] In addition, polyethylene itself is a flammable material with an ultra-high relative molecular mass, but its chemical structure contains a large number of CH covalent bonds and has high flammability. Its limiting oxygen index is only about 17.4%, which limits its application in high-temperature environments.

[0005] The existing halogen-free flame retardant method is to add magnesium hydroxide and aluminum hydroxide to polyethylene materials to achieve flame retardancy, which has the disadvantage of low flame retardant efficiency; and its flame retardant effect usually requires the addition of a large amount of inorganic fillers to achieve, such a large amount of inorganic fillers often causes a significant reduction in the processing performance and mechanical properties of the composite material, and it is even more difficult to meet the high requirements of military vehicle cables for tensile and drag performance. Summary of the invention

[0006] The purpose of the present invention is to overcome the defects of the prior art and provide a method for manufacturing a tensile dragging optical-electric composite cable.

[0007] The raw material of the polyethylene outer sheath of the present invention uses PE resin as a matrix, and ethylene-vinyl acetate EVA is added. EVA can not only play a toughening effect to improve the toughness of the polyethylene matrix, but also play an interface strengthening role between the polyethylene matrix and the flame retardant additive and calcium carbonate, thereby improving the comprehensive mechanical properties of the polyethylene outer sheath. In addition, the added flame retardant additive is an organic compound, which is a composite flame retardant component containing three effective flame retardant elements of N, P and S. N, P and S can play a synergistic role to improve the flame retardant performance of the PE matrix from different angles, and the flame retardant additive can react chemically with the PE matrix, which can not only improve the migration resistance of the flame retardant and improve the effective flame retardant effect, but also due to the good interaction with the matrix, the addition of the flame retardant additive will not affect the mechanical properties of the polyethylene outer sheath. The obtained polyethylene outer sheath not only has tensile drag resistance, but also has excellent flame retardant properties, so that the composite cable can be suitable for more stringent places.

[0008] The purpose of the present invention can be achieved through the following technical solutions:

[0009] A tensile dragging photoelectric composite cable, comprising a power line, an optical fiber and a filling rope at the core, wherein the power line, the optical fiber and the filling rope form a cable core, the cable core is coated with a metal double-sided plastic-coated steel belt, and the outer layer of the metal double-sided plastic-coated steel belt is coated with a polyethylene outer sheath;

[0010] The polyethylene outer sheath comprises the following raw materials in parts by weight: 50-60 parts of polyethylene resin, 5-6 parts of ethylene vinyl acetate (EVA), 3-4 parts of flame retardant additives, 3-4 parts of modified calcium carbonate, 0.2-0.3 parts of antioxidants, and 0.2-0.3 parts of lubricants;

[0011] The flexible chains of EVA molecules can weaken the entanglement between PE matrices, have a toughening effect on PE, and thus improve the toughness of the cable outer sheath, giving it tensile and drag resistance; EVA contains ethylene segments, which have high compatibility with the polyethylene matrix, and the EVA molecular chain contains vinyl acetate, which has a certain polarity and is highly compatible with the polar groups in the flame retardant additives and calcium carbonate, thereby playing an interface enhancement role.

[0012] A method for manufacturing a tensile dragging optical-electric composite cable comprises the following steps:

[0013] The first step is to prepare a flame retardant additive;

[0014] The second step is to mix polyethylene resin, ethylene vinyl acetate (EVA), flame retardant additives, modified calcium carbonate, antioxidants and lubricants according to weight ratios, and extrude and granulate them using a twin-screw extruder to obtain a polyethylene outer sheath material;

[0015] The third step is to make the power cord, optical fiber and filling rope into a cable core according to the specifications, cover the cable core with a metal double-sided plastic-coated steel tape, and finally wrap the polyethylene outer sheath material around the surface of the metal double-sided plastic-coated steel tape to form a polyethylene outer sheath to obtain a photoelectric composite cable.

[0016] Furthermore, the antioxidant is antioxidant 1010 or antioxidant 168.

[0017] Furthermore, the lubricant is dimethyl silicone oil.

[0018] Furthermore, the modified calcium carbonate is calcium carbonate treated with silane coupling agent KH570; after calcium carbonate is treated with silane coupling agent KH570, its interface performance with the PE matrix can be improved. At the same time, under the interface strengthening effect of EVA molecules, calcium carbonate can be evenly dispersed in the matrix, playing a role in enhancing mechanical properties, improving the mechanical properties of the polyethylene outer sheath, that is, improving the tensile drag performance of the composite cable.

[0019] Further, the preparation process of the flame retardant additive is as follows:

[0020] S1. Add 1,4-butanediamine to a three-necked flask, then add an appropriate amount of triethylamine as an acid-binding agent, stir evenly, fix the three-necked flask in an ice-water bath, and then drop diethyl chlorophosphate under nitrogen protection. After the drop is complete, heat to 35°C and react for 12 hours. After the reaction is completed, rotary evaporate to obtain an intermediate product; the ratio of 1,4-butanediamine, triethylamine and diethyl chlorophosphate is 8.8g:20mL:17.3g;

[0021] Under the condition of triethylamine as an acid-binding agent, -NH2 on the 1,4-butanediamine molecule reacts with -Cl on the diethyl chlorophosphate molecule to obtain an intermediate product. By controlling the dosage ratio of 1,4-butanediamine to diethyl chlorophosphate (molar ratio 1:1), -NH2 at one end of 1,4-butanediamine participates in the reaction, and -NH2 at the other end lays a reaction site for subsequent reactions. The specific reaction process is shown below:

[0022]

[0023] S2. Add the intermediate product and solvent DMSO into a three-necked flask, then add dicyclohexylcarbodiimide (condensing agent) and 4-N,N-lutidine (catalyst), stir and heat to 60°C, add 4-ethylenesulfonylbenzoic acid under uniform stirring, react at a constant temperature of 60°C for 2h, wash the product with acetonitrile, and then purify it in a rotary evaporator to obtain a flame retardant additive; the ratio of the intermediate product, DMSO, dicyclohexylcarbodiimide, 4-N,N-lutidine and 4-ethylenesulfonylbenzoic acid is 23g:300mL:0.26g:0.09g:21.2g;

[0024] Under the action of the catalyst and the condensation agent, -NH2 on the intermediate product molecule reacts with -COOH on the 4-ethylenesulfonylbenzoic acid molecule to obtain a flame retardant additive. The reaction process is as follows:

[0025]

[0026] The flame retardant additive obtained is a composite flame retardant component containing three effective flame retardant elements, N, P and S. N, P and S can play a synergistic role to improve the flame retardant performance of the PE matrix from different angles. Specifically, in the condensed phase: SO2 and SO3 formed by the decomposition of the sulfonate structure promote the cross-linking of PE into carbon, and substances such as phosphoric acid and metaphosphoric acid generated by the decomposition of the phosphorus-containing group adhere to the surface of the carbon layer, and work together to form a honeycomb-shaped carbon layer with a very small pore size to insulate and isolate oxygen, thereby playing a flame retardant role; in the gas phase: the free radical PO· in the gas phase decomposition product of the flame retardant additive combines with highly active free radicals such as H· and OH· in the flame to interrupt the chain reaction of the combustion of the PE substrate; N, P and S work synergistically from the condensed phase and the gas phase to improve the flame retardant effect of the PE substrate;

[0027] On the other hand, the flame retardant additive contains carbon-carbon double bonds in its molecular structure. During the melt blending process of the polyethylene sheath layer raw materials, it can participate in the polymerization process of polyethylene, so that the flame retardant additive molecules are combined with the PE matrix by chemical bonding, which can not only improve the migration resistance of the flame retardant and improve the effective flame retardant effect, but also because of the good interaction with the matrix, the addition of the flame retardant additive will not affect the mechanical properties of the polyethylene outer sheath; and, the other end of the benzene ring of the flame retardant additive molecule is connected to a flexible molecular chain, so that the flame retardant additive can improve the flexibility of the polyethylene outer sheath to a certain extent and enhance the tensile drag performance.

[0028] Beneficial effects of the present invention:

[0029] The raw material of the polyethylene outer sheath of the present invention uses PE resin as a matrix, and ethylene-vinyl acetate EVA is added. EVA can not only play a toughening effect to improve the toughness of the polyethylene matrix, but also play an interface strengthening role between the polyethylene matrix and the flame retardant additive and calcium carbonate, thereby improving the comprehensive mechanical properties of the polyethylene outer sheath. In addition, the added flame retardant additive is an organic compound, which is a composite flame retardant component containing three effective flame retardant elements of N, P and S. N, P and S can play a synergistic role to improve the flame retardant performance of the PE matrix from different angles, and the flame retardant additive can react chemically with the PE matrix, which can not only improve the migration resistance of the flame retardant and improve the effective flame retardant effect, but also due to the good interaction with the matrix, the addition of the flame retardant additive will not affect the mechanical properties of the polyethylene outer sheath. The obtained polyethylene outer sheath not only has tensile drag resistance, but also has excellent flame retardant properties, so that the composite cable can be suitable for more stringent places. DETAILED DESCRIPTION

[0030] 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.

[0031] Example 1

[0032] Preparation of flame retardant additives:

[0033] S1. Add 8.8 g of 1,4-butanediamine to a three-necked flask, then add 20 mL of triethylamine as an acid-binding agent, stir evenly, fix the three-necked flask in an ice-water bath, and then drop 17.3 g of diethyl chlorophosphate under nitrogen protection. After the drop is complete, heat to 35°C and react for 12 hours. After the reaction is completed, rotary evaporate to obtain an intermediate product;

[0034] S2. Add 23 g of the intermediate product and 300 mL of solvent DMSO into a three-necked flask, then add 0.26 g of dicyclohexylcarbodiimide (condensation agent) and 0.09 g of 4-N,N-dimethylpyridine (catalyst), stir and heat to 60°C, add 21.2 g of 4-ethylenesulfonylbenzoic acid under uniform stirring, react at a constant temperature of 60°C for 2 hours, wash the product with acetonitrile, and then put it into a rotary evaporator for purification to obtain a flame retardant additive.

[0035] Example 2

[0036] Preparation of flame retardant additives:

[0037] S1. Add 17.6 g of 1,4-butanediamine to a three-necked flask, then add 40 mL of triethylamine as an acid-binding agent, stir evenly, fix the three-necked flask in an ice-water bath, and then drop 34.6 g of diethyl chlorophosphate under nitrogen protection. After the drop is complete, heat to 35°C and react for 12 hours. After the reaction is completed, rotary evaporate to obtain an intermediate product;

[0038] S2. Add 46 g of the intermediate product and 600 mL of solvent DMSO into a three-necked flask, then add 0.52 g of dicyclohexylcarbodiimide (condensation agent) and 0.18 g of 4-N,N-dimethylpyridine (catalyst), stir and heat to 60°C, add 42.4 g of 4-ethylenesulfonylbenzoic acid under uniform stirring, react at a constant temperature of 60°C for 2 hours, wash the product with acetonitrile, and then put it into a rotary evaporator for purification to obtain a flame retardant additive.

[0039] Example 3

[0040] Preparation of modified calcium carbonate:

[0041] Disperse 10 g of nano-calcium carbonate in 150 mL of ethanol-water solution (the volume ratio of ethanol to water is 1:1), add 2.2 g of silane coupling agent KH570, stir and react for 2 h, filter, wash with ethanol and deionized water three times in sequence, and dry in a vacuum oven at 60 ° C to constant weight to obtain modified calcium carbonate.

[0042] Example 4

[0043] A method for manufacturing a tensile dragging optical-electric composite cable comprises the following steps:

[0044] The first step is to mix 50g of polyethylene resin, 5g of ethylene-vinyl acetate (EVA), 3g of the flame retardant additive prepared in Example 1, 3g of the modified calcium carbonate prepared in Example 3, 0.2g of antioxidant 1010, and 0.2g of dimethyl silicone oil, and extrude and granulate them using a twin-screw extruder to obtain a polyethylene outer sheath material;

[0045] The second step is to make the power cord, optical fiber and filling rope into a cable core according to the specifications, and cover the cable core with a metal double-sided plastic-coated steel tape. Finally, wrap the polyethylene outer sheath material around the surface of the metal double-sided plastic-coated steel tape to form a polyethylene outer sheath to obtain a photoelectric composite cable.

[0046] Example 5

[0047] A method for manufacturing a tensile dragging optical-electric composite cable comprises the following steps:

[0048] The first step is to mix 55 g of polyethylene resin, 5.5 g of ethylene vinyl acetate (EVA), 3.5 g of the flame retardant additive prepared in Example 1, 3.5 g of the modified calcium carbonate prepared in Example 3, 0.25 g of antioxidant 168, and 0.25 g of dimethyl silicone oil, and extrude and granulate them using a twin-screw extruder to obtain a polyethylene outer sheath material;

[0049] The second step is to make the power cord, optical fiber and filling rope into a cable core according to the specifications, and cover the cable core with a metal double-sided plastic-coated steel tape. Finally, wrap the polyethylene outer sheath material around the surface of the metal double-sided plastic-coated steel tape to form a polyethylene outer sheath to obtain a photoelectric composite cable.

[0050] Example 6

[0051] A method for manufacturing a tensile dragging optical-electric composite cable comprises the following steps:

[0052] The first step is to mix 60g of polyethylene resin, 6g of ethylene-vinyl acetate (EVA), 4g of the flame retardant additive prepared in Example 1, 4g of the modified calcium carbonate prepared in Example 3, 0.3g of antioxidant 1010, and 0.3g of dimethyl silicone oil, and extrude and granulate them using a twin-screw extruder to obtain a polyethylene outer sheath material;

[0053] The second step is to make the power cord, optical fiber and filling rope into a cable core according to the specifications, and cover the cable core with a metal double-sided plastic-coated steel tape. Finally, wrap the polyethylene outer sheath material around the surface of the metal double-sided plastic-coated steel tape to form a polyethylene outer sheath to obtain a photoelectric composite cable.

[0054] Comparative Example 1

[0055] The EVA raw material in Example 4 was replaced with polyethylene resin, and the other raw materials and preparation process remained unchanged.

[0056] Comparative Example 2

[0057] The flame retardant additive raw material in Example 4 was removed, and the other raw materials and preparation process remained unchanged.

[0058] The polyethylene outer sheath materials obtained in Examples 4-6 and Comparative Examples 1-2 were subjected to the following performance tests:

[0059] Tensile strength and tensile strain at break were tested according to GB / T 1040.3-2006, with a test speed of (25+5) mm / min;

[0060] Limiting oxygen index test: tested according to GB / T 2406-2009; Vertical burning test: tested according to UL 94-2016;

[0061] The measured results are shown in the following table:

[0062]

[0063] It can be seen from the data in the above table that the polyethylene outer sheath material obtained in Examples 4-6 has higher mechanical properties (tensile strength of 25.8MPa and above, tensile strain at break of 781% and above), indicating that the optoelectronic composite cable obtained in the present invention has higher mechanical properties and better tensile and dragging performance; the LOI index of the polyethylene outer sheath material obtained in Examples 4-6 is 26.9% and above, and the combustion performance grade reaches the VO grade, indicating that the polyethylene outer sheath material obtained in the present invention has excellent flame retardant properties; the optoelectronic composite cable obtained in the present invention has higher mechanical properties and flame retardant properties, good tensile and dragging performance, and can be used in harsh workplaces; combined with the data of Comparative Example 1, it can be seen that the addition of EVA can not only have a toughening effect, but also promote the flame retardant effect of the flame retardant additive; combined with the data of Comparative Example 2, it can be seen that the addition of flame retardant additives can give the polyethylene outer sheath layer good flame retardant properties, and the flexible molecular chains contained therein can improve the flexibility of the polyethylene matrix to a certain extent.

[0064] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0065] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A method for manufacturing a tensile dragging optical fiber composite cable, the optical fiber composite cable comprising a power cord, an optical fiber and a filling rope at the core, the power cord, the optical fiber and the filling rope forming a cable core, the cable core is coated with a metal double-sided plastic-coated steel belt, the outer layer of the metal double-sided plastic-coated steel belt is coated with a polyethylene outer sheath, characterized in that: The manufacturing method thereof comprises the following steps: The first step is to prepare flame retardant additives: S1. Add 1,4-butanediamine to a three-necked flask, then add an appropriate amount of triethylamine as an acid-binding agent, stir evenly, fix the three-necked flask in an ice-water bath, and then drop diethyl chlorophosphate under nitrogen protection. After the drop is complete, heat to 35°C and react for 12 hours. After the reaction is completed, rotary evaporate to obtain an intermediate product; S2. Add the intermediate product and solvent DMSO into a three-necked flask, then add dicyclohexylcarbodiimide and 4-N,N-dimethylpyridine, stir and heat to 60°C, add 4-ethylenesulfonylbenzoic acid under uniform stirring, react at a constant temperature of 60°C for 2h, wash the product with acetonitrile, and then purify it in a rotary evaporator to obtain a flame retardant additive. The structure of the flame retardant additive is shown below: The second step is to mix 50-60 parts of polyethylene resin, 5-6 parts of ethylene-vinyl acetate, 3-4 parts of flame retardant additives, 3-4 parts of modified calcium carbonate, 0.2-0.3 parts of antioxidants, and 0.2-0.3 parts of lubricants according to the weight ratio, and extrude and granulate them using a twin-screw extruder to obtain a polyethylene outer sheath material; The third step is to make the power cord, optical fiber and filling rope into a cable core according to the specifications, cover the cable core with a metal double-sided plastic-coated steel tape, and finally wrap the polyethylene outer sheath material around the surface of the metal double-sided plastic-coated steel tape to form a polyethylene outer sheath to obtain a photoelectric composite cable.

2. The method for manufacturing a tensile dragging optical-electric composite cable according to claim 1, characterized in that: The antioxidant is antioxidant 1010 or antioxidant 168.

3. The method for manufacturing a tensile dragging optical-electric composite cable according to claim 1, characterized in that: The lubricant is dimethyl silicone oil.

4. The method for manufacturing a tensile dragging optical-electric composite cable according to claim 1, characterized in that: The modified calcium carbonate is calcium carbonate treated with silane coupling agent KH570.

5. The method for manufacturing a tensile dragging optical-electric composite cable according to claim 1, characterized in that: In step S1, the ratio of 1,4-butanediamine, triethylamine and diethyl chlorophosphate is 8.8 g:20 mL:17.3 g.

6. The method for manufacturing a tensile dragging optical-electric composite cable according to claim 1, characterized in that: In step S2, the ratio of the amount of the intermediate product, DMSO, dicyclohexylcarbodiimide, 4-N,N-dimethylpyridine and 4-ethylenesulfonylbenzoic acid is 23 g: 300 mL: 0.26 g: 0.09 g: 21.2 g.

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