Production process of flame-retardant laminated belt for coal mine

Abstract

The invention relates to a production process of a flame-retardant laminated belt for a coal mine, and belongs to the technical field of transportation auxiliary materials. The flame-retardant laminated belt is composed of a laminated core belt, a vulcanization bonding layer and a flame-retardant covering surface layer, and the flame-retardant covering surface layer is prepared from 8 wt%-12 wt% of butadiene rubber, 32 wt%-38 wt% of a magnesium hydroxide flame retardant, 4 wt%-5.2 wt% of a reinforcing agent, 4.5 wt%-7.5 wt% of a modified synergist, 1.2 wt%-1.5 wt% of a vulcanizing agent, 0.25 wt%-0.3 wt% of an accelerant, 0.1 wt%-0.12 wt% of an anti-aging agent and the balance chloroprene rubber; the modified synergist is prepared by self-polymerizing N-phenyl p-phenylenediamine to form short-chain polyaniline and then carrying out amine ester exchange on methyl thioglycolate and terminal amino groups of the short-chain polyaniline, and the modified synergist with chelating-crosslinking dual functions realizes multi-dimensional optimization of a magnesium hydroxide flame-retardant system.

Description

Technical Field

[0001] The present invention belongs to the technical field of transportation auxiliary materials, and in particular relates to a production process of a flame-retardant laminated belt for coal mines. Background Art

[0002] Flame-retardant laminated belts for coal mines are key components of underground conveying systems. Their flame retardancy and mechanical properties are directly related to safe coal mine production. Traditional technologies often use inorganic hydroxides (such as magnesium hydroxide and aluminum hydroxide) as flame retardants, leveraging their ability to decompose upon heating, releasing water of crystallization that absorbs heat and forms a metal oxide coating to achieve flame retardancy. However, these flame retardants have the following insurmountable drawbacks: The interface compatibility between inorganic particles and the rubber matrix is ​​poor. Excessive filling leads to a significant decrease in the toughness and wear resistance of the material. Insufficient filling leads to an insignificant flame retardant effect, which makes it difficult to meet the flame retardant requirements for mining, resulting in difficulty in synergistic optimization of mechanical properties and flame retardant properties. In the existing technology, in order to reduce the amount of inorganic flame retardants used, some technologies have attempted to introduce high-efficiency organic flame retardants such as phosphorus and nitrogen. Although their flame retardant efficiency is relatively high, this type of flame retardant itself has insufficient thermal stability and is prone to thermal migration during high-temperature vulcanization. The amount of high-efficiency organic flame retardants used is not commensurate with the performance improvement, and their development in industrial production is greatly restricted. In addition, the composite flame retardant system, especially the high-content organic flame retardant system, lacks continuous carbon layer support during combustion, which easily produces molten droplets, posing a greater risk to coal mining. Summary of the Invention

[0003] In order to solve the technical problems mentioned in the background technology, the purpose of the present invention is to provide a production process of flame-retardant laminated belts for coal mines.

[0004] The purpose of the present invention can be achieved through the following technical solutions: A flame-retardant laminated belt for coal mines consists of a laminated core belt, a vulcanized adhesive layer and a flame-retardant covering layer. The flame-retardant covering layer comprises 8-12 wt% of butadiene rubber, 32-38 wt% of a magnesium hydroxide flame retardant, 4-5.2 wt% of a reinforcing agent, 4.5-7.5 wt% of a modifying synergist, 1.2-1.5 wt% of a vulcanizing agent, 0.25-0.3 wt% of an accelerator and 0.1-0.12 wt% of an antioxidant, with the balance being chloroprene rubber.

[0005] The modified synergist is prepared by the following method: Step A1: Premix N-phenyl-p-phenylenediamine and tetrahydrofuran under a nitrogen atmosphere, add hydrochloric acid to acidify the premixed solution to a pH of 3-4, control the temperature in a water bath at 40-55°C, slowly add ammonium persulfate solution and stir to react for 5.5-7 hours, add water to wash the precipitate, and wash until neutral to obtain an intermediate; In the reaction of step A1 above, the ratio of N-phenyl-p-phenylenediamine, ammonium persulfate and tetrahydrofuran is 0.1 mol: 2.2-2.8 g: 150-200 mL. Under acidic oxidation conditions, N-phenyl-p-phenylenediamine self-polymerizes to form short-chain polyaniline. The specific reaction route is as follows:

[0006] Step A2: The intermediate, methyl thioglycolate, and dimethyl sulfoxide are mixed under a dry atmosphere, trimethylaluminum is added, the mixture is heated to 90-110°C, and the mixture is stirred for 2.5-3.2 hours. The dimethyl sulfoxide is evaporated under reduced pressure, and the substrate is washed with ethanol solution and dried to obtain a modified synergist; In the above step A2 reaction, the ratio of the intermediate, methyl thioglycolate, trimethylaluminum, and dimethyl sulfoxide is 10 g: 8-12 mmol: 25-40 mg: 65-85 mL. Under the catalysis of trimethylaluminum, the intermediate and methyl thioglycolate undergo amine transesterification. The specific reaction route is as follows:

[0007] Preferably, the reinforcing agent is carbon black, which has a smaller particle size, good reinforcing effect, and can provide a certain degree of conductivity, and synergistically improve the antistatic ability of the flame retardant covering layer with the modified synergist.

[0008] Preferably, the vulcanizing agent is sulfur, which has good vulcanizing ability for both the rubber matrix and the modifying synergist.

[0009] A production process for flame-retardant laminated tape for coal mines, comprising the following steps: Step S1: Neoprene and butadiene rubber are mixed and plasticized, and an accelerator and an antioxidant are added for pre-mixing. Then, magnesium hydroxide flame retardant, a reinforcing agent and a modifier are added for final mixing. Finally, a vulcanizing agent is added and thinned to obtain a raw rubber sheet. Step S2: applying vulcanized rubber on the surface of the laminated core tape, cold pressing and laminating the raw rubber sheets, steam pressurizing and vulcanizing, and discharging the material to obtain a flame-retardant laminated tape.

[0010] In step S1, the plasticating temperature is 55°C and the mixing temperature is 90-100°C.

[0011] In step S2, the temperature of steam pressurized vulcanization is 145-160° C., the steam pressure is 0.5-0.6 MPa, and the vulcanization time is 60-80 min.

[0012] Beneficial effects of the present invention: The present invention is based on the existing inorganic flame retardant system, adopts magnesium hydroxide as a flame retardant, introduces a modified synergist with chelating-crosslinking dual functions, and realizes multi-dimensional optimization of the magnesium hydroxide flame retardant system. The modified synergist is formed by self-polymerization of N-phenyl-p-phenylenediamine to form a short-chain polyaniline, and then methyl thioglycolate and its terminal amino group are subjected to amine ester exchange; the thioamide structure in the modified synergist molecule forms a chelate effect with the magnesium hydroxide, and at the same time, the terminal thiol group is cross-linked with the rubber molecular chain to construct a strong interface layer between the inorganic phase and the organic phase, which significantly improves the reinforcement efficiency of the magnesium hydroxide, and significantly improves the mechanical strength and wear resistance of the flame retardant covering layer; under the chelating composite action, the short-chain polyaniline is anchored to the magnesium hydroxide. On the surface of magnesium, a magnesium hydroxide-polyaniline composite unit is formed. Its polybenzene ring conjugated structure acts as an electron transmission bridge, and cooperates with reinforcing agents such as carbon black to construct a three-dimensional conductive path, which significantly reduces the resistivity and effectively inhibits static electricity accumulation. During the combustion process, the polybenzene ring structure of polyaniline is rapidly carbonized to form a dense network skeleton, which is compounded with the magnesium oxide particles generated by the decomposition of magnesium hydroxide to form a carbon-ceramic composite barrier layer with significant oxygen and smoke suppression effects. At the same time, the carbon layer effectively supports the material morphology and avoids the generation of molten droplets. There is no molten droplet phenomenon in the vertical combustion test. In addition, the modified enhancer can be directly added during the mixing process without the need for complex pretreatment. It is highly compatible with existing rubber processing technology and is suitable for industrial production. DETAILED DESCRIPTION

[0013] 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 embodiments described 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 making any creative efforts shall fall within the scope of protection of the present invention.

[0014] Example 1: Preparation of flame retardant laminated tape, specifically as follows: 1. Preparation of modified synergist Step A1: N-phenyl-p-phenylenediamine and tetrahydrofuran were premixed under a nitrogen atmosphere, and hydrochloric acid was added to acidify the premixed solution to a pH of 3. The temperature of the water bath was controlled at 40°C, and a 1% (mass fraction) aqueous solution of ammonium persulfate was slowly added and stirred for 7 hours. The amount ratio of N-phenyl-p-phenylenediamine, ammonium persulfate, and tetrahydrofuran was 0.1 mol:2.2 g:150 mL. Finally, water was added to wash the precipitate, and the precipitate was washed until neutral to obtain an intermediate.

[0015] Step A2: The intermediate, methyl thioglycolate and dimethyl sulfoxide were mixed in a dry atmosphere, trimethylaluminum was added and mixed, the temperature was raised to 90°C, and the reaction was stirred for 3.2 hours. The amount ratio of the intermediate, methyl thioglycolate, trimethylaluminum and dimethyl sulfoxide was 10g:8mmol:40mg:65mL. Finally, dimethyl sulfoxide was evaporated under reduced pressure, and the substrate was washed with ethanol solution and dried to obtain a modified synergist.

[0016] 2. Preparation of flame retardant laminated tape The components of the flame retardant covering layer in this embodiment are: 10wt% of butadiene rubber, BR9000 type rubber raw material; 32wt% of magnesium hydroxide flame retardant, XS-MHS-25 type commercial flame retardant; 5.2wt% of reinforcing agent, N550 type carbon black; 4.5wt% of modifying synergist, homemade in the embodiment; 1.5wt% of vulcanizing agent, vulcanizing agent grade sulfur powder raw material; 0.3wt% of accelerator, accelerator TMTD; 0.12wt% of antioxidant, antioxidant RD; the balance is chloroprene rubber, CR3222 type rubber raw material; Step S1: Neoprene and butadiene rubber are mixed and masticated at 55°C for 15 minutes, followed by adding an accelerator and an antioxidant, pre-mixing at 90°C for 5 minutes, adding a magnesium hydroxide flame retardant, a reinforcing agent, and a modifier and synergist, and finally mixing for 8 minutes. The mixed rubber is thinned three times and a vulcanizing agent is added, and the raw rubber sheet is obtained. Step S2: Based on the required conveying strength of the coal mine, a steel wire laminated core belt is selected, and YFL 9288 type vulcanized rubber is scraped on the surface. A raw rubber sheet is laminated on the surface of the vulcanized rubber, and the laminated belt is cold-pressed at 1.5 MPa. The belt is then placed in a vulcanizing kettle and subjected to steam pressurization vulcanization. The process parameters are controlled as follows: temperature of 160° C., steam pressure of 0.6 MPa, and vulcanization time of 60 minutes. The raw rubber sheet is vulcanized to form a flame-retardant covering layer, and the interlayer vulcanized rubber is vulcanized to form a vulcanized bonding layer, thereby obtaining a flame-retardant laminated belt.

[0017] Example 2: Preparation of flame retardant laminated tape, specifically as follows: 1. Preparation of modified synergist Step A1: N-phenyl-p-phenylenediamine and tetrahydrofuran were premixed under a nitrogen atmosphere, and hydrochloric acid was added to acidify the premixed solution to a pH of 4. The temperature of the water bath was controlled at 55°C. A 1% (mass fraction) aqueous solution of ammonium persulfate was slowly added and stirred for 5.5 hours. The amount ratio of N-phenyl-p-phenylenediamine, ammonium persulfate, and tetrahydrofuran was 0.1 mol:2.8 g:200 mL. Finally, water was added to wash the precipitate, and the precipitate was washed until neutral to obtain an intermediate.

[0018] Step A2: The intermediate, methyl thioglycolate and dimethyl sulfoxide were mixed in a dry atmosphere, trimethylaluminum was added and mixed, the temperature was raised to 110°C, and the reaction was stirred for 2.5 hours. The amount ratio of the intermediate, methyl thioglycolate, trimethylaluminum and dimethyl sulfoxide was 10g:12mmol:25mg:85mL. Finally, dimethyl sulfoxide was evaporated under reduced pressure, and the substrate was washed with ethanol solution and dried to obtain a modified synergist.

[0019] 2. Preparation of flame retardant laminated tape The components of the flame retardant covering layer in this embodiment are: 8wt% of butadiene rubber, BR9000 type rubber raw material; 38wt% of magnesium hydroxide flame retardant, XS-MHS-25 type commercial flame retardant; 4wt% of reinforcing agent, N550 type carbon black; 7.5wt% of modifying synergist, homemade in the embodiment; 1.2wt% of vulcanizing agent, vulcanizing agent grade sulfur powder raw material; 0.25wt% of accelerator, accelerator TMTD; 0.1wt% of antioxidant, antioxidant RD; the balance is chloroprene rubber, CR3222 type rubber raw material; Step S1: Neoprene and butadiene rubber are mixed and masticated at 55°C for 15 minutes, followed by adding an accelerator and an antioxidant, pre-mixing at 100°C for 3 minutes, adding a magnesium hydroxide flame retardant, a reinforcing agent, and a modifier and synergist, and finally mixing for 11 minutes. The mixed rubber is thinned four times, a vulcanizing agent is added, and the raw rubber sheet is obtained. Step S2: Based on the required conveying strength of the coal mine, a steel wire laminated core belt is selected, and YFL 9288 type vulcanized rubber is scraped on the surface. A raw rubber sheet is laminated on the surface of the vulcanized rubber, and the laminated belt is cold-pressed at 1.5 MPa. The belt is then placed in a vulcanizing kettle and subjected to steam pressurization vulcanization. The process parameters are controlled as follows: temperature of 145° C., steam pressure of 0.5 MPa, and vulcanization time of 80 minutes. The raw rubber sheet is vulcanized to form a flame-retardant covering layer, and the interlayer vulcanized rubber is vulcanized to form a vulcanized bonding layer, thereby obtaining a flame-retardant laminated belt.

[0020] Example 3, preparing a flame retardant laminated tape, specifically as follows: 1. Preparation of modified synergist Step A1: N-phenyl-p-phenylenediamine and tetrahydrofuran were premixed under a nitrogen atmosphere, and hydrochloric acid was added to acidify the premixed solution to a pH of 4. The temperature of the water bath was controlled at 50°C, and a 1% (mass fraction) aqueous solution of ammonium persulfate was slowly added and stirred for 6.5 hours. The amount ratio of N-phenyl-p-phenylenediamine, ammonium persulfate, and tetrahydrofuran was 0.1 mol:2.4 g:180 mL. Finally, water was added to wash the precipitate, and the precipitate was washed until neutral to obtain an intermediate.

[0021] Step A2: The intermediate, methyl thioglycolate and dimethyl sulfoxide were mixed in a dry atmosphere, trimethylaluminum was added and mixed, the temperature was raised to 100°C, and the reaction was stirred for 2.8 hours. The amount ratio of the intermediate, methyl thioglycolate, trimethylaluminum and dimethyl sulfoxide was 10g:10mmol:30mg:70mL. Finally, dimethyl sulfoxide was evaporated under reduced pressure, and the substrate was washed with ethanol solution and dried to obtain a modified synergist.

[0022] 2. Preparation of flame retardant laminated tape The components of the flame retardant covering layer in this embodiment are: 12wt% of butadiene rubber, BR9000 type rubber raw material; 35wt% of magnesium hydroxide flame retardant, XS-MHS-25 type commercial flame retardant; 4.5wt% of reinforcing agent, N550 type carbon black; 7wt% of modifying synergist, homemade in the embodiment; 1.3wt% of vulcanizing agent, vulcanizing agent grade sulfur powder raw material; 0.28wt% of accelerator, accelerator TMTD; 0.1wt% of antioxidant, antioxidant RD; the balance is chloroprene rubber, CR3222 type rubber raw material; Step S1: Neoprene and butadiene rubber are mixed and masticated at 55°C for 15 minutes, followed by adding an accelerator and an antioxidant, pre-mixing at 100°C for 4 minutes, adding a magnesium hydroxide flame retardant, a reinforcing agent, and a modifier and synergist, and finally mixing for 10 minutes. The mixed rubber is thinned four times, a vulcanizing agent is added, and the raw rubber sheet is obtained. Step S2: Based on the required conveying strength of the coal mine, a steel wire laminated core belt is selected, and YFL 9288 type vulcanized rubber is scraped on the surface. A raw rubber sheet is laminated on the surface of the vulcanized rubber, and the laminated belt is cold-pressed at 1.5 MPa. The belt is then placed in a vulcanizing kettle and subjected to steam pressurization vulcanization. The process parameters are controlled as follows: temperature of 150° C., steam pressure of 0.5 MPa, and vulcanization time of 75 minutes. The raw rubber sheet is vulcanized to form a flame-retardant covering layer, and the interlayer vulcanized rubber is vulcanized to form a vulcanized bonding layer, thereby obtaining a flame-retardant laminated belt.

[0023] Example 4, preparing a flame retardant laminated tape, specifically as follows: 1. Preparation of modified synergist Step A1: N-phenyl-p-phenylenediamine and tetrahydrofuran were premixed under a nitrogen atmosphere, and hydrochloric acid was added to acidify the premixed solution to a pH of 3. The temperature of the water bath was controlled at 45°C, and a 1% (mass fraction) aqueous solution of ammonium persulfate was slowly added and stirred for 6 hours. The amount ratio of N-phenyl-p-phenylenediamine, ammonium persulfate, and tetrahydrofuran was 0.1 mol:2.6 g:160 mL. Finally, water was added to wash the precipitate, and the precipitate was washed until neutral to obtain an intermediate.

[0024] Step A2: The intermediate, methyl thioglycolate and dimethyl sulfoxide were mixed in a dry atmosphere, trimethylaluminum was added and mixed, the temperature was raised to 110°C, and the reaction was stirred for 2.7 hours. The amount ratio of the intermediate, methyl thioglycolate, trimethylaluminum and dimethyl sulfoxide was 10g:9mmol:35mg:80mL. Finally, dimethyl sulfoxide was evaporated under reduced pressure, and the substrate was washed with ethanol solution and dried to obtain a modified synergist.

[0025] 2. Preparation of flame retardant laminated tape The components of the flame retardant covering layer in this embodiment are: 11wt% of butadiene rubber, BR9000 type rubber raw material; 35wt% of magnesium hydroxide flame retardant, XS-MHS-25 type commercial flame retardant; 4.8wt% of reinforcing agent, N550 type carbon black; 6.2wt% of modifying synergist, homemade in the embodiment; 1.3wt% of vulcanizing agent, vulcanizing agent grade sulfur powder raw material; 0.25wt% of accelerator, accelerator TMTD; 0.11wt% of antioxidant, antioxidant RD; the balance is chloroprene rubber, CR3222 type rubber raw material; Step S1: Neoprene and butadiene rubber are mixed and masticated at 55°C for 15 minutes, followed by adding an accelerator and an antioxidant, pre-mixing at 100°C for 5 minutes, adding a magnesium hydroxide flame retardant, a reinforcing agent, and a modifier and synergist, and finally mixing for 10 minutes. The mixed rubber is thinned four times and a vulcanizing agent is added, and the raw rubber sheet is obtained. Step S2: Based on the required conveying strength of the coal mine, a steel wire laminated core belt is selected, and YFL 9288 type vulcanized rubber is scraped on the surface. A raw rubber sheet is laminated on the surface of the vulcanized rubber, and the laminated belt is cold-pressed at 1.5 MPa. The belt is then placed in a vulcanizing kettle and subjected to steam pressurization vulcanization. The process parameters are controlled as follows: temperature of 155° C., steam pressure of 0.6 MPa, and vulcanization time of 70 minutes. The raw rubber sheet is vulcanized to form a flame-retardant covering layer, and the interlayer vulcanized rubber is vulcanized to form a vulcanized bonding layer, thereby obtaining a flame-retardant laminated belt.

[0026] Comparative Example 1: This comparative example refers to Example 4, except that no modifying synergist is added, and the balance is made up of chloroprene rubber to 100 wt %. The rest of the implementation process is exactly the same.

[0027] Comparative Example 2: This comparative example refers to Example 4, except that the modified synergist is replaced by 1.8 wt % of silane coupling agent KH-580 and 4.4 wt % of polyaniline, and the rest of the implementation process is exactly the same.

[0028] The flame retardant covering layer is subjected to relevant performance tests, including: basic performance test, hardness test is performed in accordance with GB / T 531.1-2008, and tensile performance test is performed in accordance with GB / T 528-2009, as shown in Table 1; performance test, flame retardant performance test is performed in accordance with AS1334.10-1994, and flame retardant grade is tested using UL94 standard, roller friction test is performed in accordance with AS1334.11-1988, and antistatic test is performed in accordance with AS1334.9-1982, as shown in Table 2; Table 1

[0029] It can be seen from the data in Table 1 that the flame retardant covering surface layer prepared above has moderate hardness, and the flame retardant covering surface layer of the embodiment has more excellent comprehensive properties of strength and toughness.

[0030] Table 2

[0031] From the test results in Table 2, it can be seen that the flame retardant time of the flame retardant covering layer prepared above is less than 10s, which has certain flame retardant ability. However, during the vertical burning test, obvious visible droplets appeared in the comparative example, and the flame retardant grade could only reach V-2. The roller wear of the embodiment was low, and the surface resistance reached 10 7 It is of high order and has good anti-static effect, which is beneficial to the safe transportation of coal mines.

[0032] Throughout the specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0033] 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 described specific embodiments or replace them in similar ways. As long as they do not deviate from the invention or exceed the scope defined by the claims, they should all fall within the scope of protection of the present invention.

Claims

1. A flame retardant laminated belt for coal mines, comprising a laminated core belt, a vulcanized adhesive layer and a flame retardant covering layer, characterized in that: The flame retardant covering layer comprises: 8-12 wt% of butadiene rubber, 32-38 wt% of magnesium hydroxide flame retardant, 4-5.2 wt% of reinforcing agent, 4.5-7.5 wt% of modifying synergist, 1.2-1.5 wt% of vulcanizing agent, 0.25-0.3 wt% of accelerator and 0.1-0.12 wt% of antioxidant, and the balance is chloroprene rubber; The modified synergist is prepared by the following method: Step A1: Premix N-phenyl-p-phenylenediamine and tetrahydrofuran under a nitrogen atmosphere, add hydrochloric acid to acidify the premixed solution to a pH of 3-4, control the temperature in a water bath at 40-55°C, slowly add ammonium persulfate solution and stir to react for 5.5-7 hours, add water to wash the precipitate, and wash until neutral to obtain an intermediate; Step A2: The intermediate, methyl thioglycolate and dimethyl sulfoxide are mixed in a dry atmosphere, trimethylaluminum is added and mixed, the temperature is raised to 90-110°C, and the reaction is stirred for 2.5-3.2 hours. The dimethyl sulfoxide is evaporated under reduced pressure, and the substrate is washed with ethanol solution and dried to obtain a modified synergist.

2. The flame retardant laminated belt for coal mines according to claim 1, characterized in that: The usage ratio of N-phenyl-p-phenylenediamine, ammonium persulfate and tetrahydrofuran is 0.1 mol: 2.2-2.8 g: 150-200 mL.

3. The flame retardant laminated belt for coal mines according to claim 2, characterized in that: The usage ratio of the intermediate, methyl thioglycolate, trimethylaluminum and dimethyl sulfoxide is 10 g: 8-12 mmol: 25-40 mg: 65-85 mL.

4. The flame retardant laminated belt for coal mines according to claim 1, characterized in that: The reinforcing agent is carbon black.

5. The flame retardant laminated belt for coal mines according to claim 1, characterized in that: The vulcanizing agent is sulfur.

6. A production process for a flame-retardant laminated tape for coal mines according to any one of claims 1 to 5, characterized in that: The process includes the following steps: Step S1: Neoprene and butadiene rubber are mixed and plasticized, and an accelerator and an antioxidant are added for pre-mixing. Then, magnesium hydroxide flame retardant, a reinforcing agent and a modifier are added for final mixing. Finally, a vulcanizing agent is added and thinned to obtain a raw rubber sheet. Step S2: applying vulcanized rubber on the surface of the laminated core tape, cold pressing and laminating the raw rubber sheets, steam pressurizing and vulcanizing, and discharging the material to obtain a flame-retardant laminated tape.

7. The production process of a flame retardant laminated tape for coal mines according to claim 6, characterized in that: The plasticizing temperature is 55℃ and the mixing temperature is 90-100℃.

8. The production process of a flame retardant laminated tape for coal mines according to claim 6, characterized in that: The temperature of steam pressurized vulcanization is 145-160°C, the steam pressure is 0.5-0.6MPa, and the vulcanization time is 60-80min.

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