Steel cord core fire-retardant conveyor belt and preparation process thereof

Abstract

The present application relates to the technical field of conveying belt, in particular to a steel cord core flame-retardant conveying belt and a preparation process thereof.The present application mixes a mercapto-terminated flame-retardant material with natural rubber and butadiene rubber in advance, and obtains a reinforced flame-retardant rubber material through stirring reaction.Then, the reinforced flame-retardant rubber material, a flame retardant, a vulcanizing agent, an accelerator, a reinforcing agent and an antioxidant are mixed, and a rubber sheet is obtained through plasticizing, mixing and calendering; the rubber sheet includes upper rubber sheets, lower rubber sheets and middle rubber sheets.A steel cord core is taken as a center, and then the middle rubber sheets are wrapped around the steel cord core, the upper and lower sides of the middle rubber sheets are respectively attached to glass fiber cloth, the outermost sides are respectively provided with the upper rubber sheets and the lower rubber sheets, and then a finished product is obtained through cold pressing and vulcanization.The finished product prepared by the present application has good flame-retardant performance, and therefore has a wide application prospect in the technical field of conveying belt.

Description

Technical Field

[0001] This invention relates to the field of conveyor belt technology, specifically to a steel wire rope core flame-retardant conveyor belt and its manufacturing process. Background Technology

[0002] In modern industrial transportation, steel cord conveyor belts play a crucial role due to their superior performance, demonstrating irreplaceable modern value. Economically, steel cord conveyor belts, with their high strength and long lifespan, significantly reduce transportation costs for enterprises. They can withstand high-load material transport, reducing the cost and time associated with frequent conveyor belt replacements. Simultaneously, their efficient transport capacity improves production efficiency, enabling enterprises to complete more transport tasks per unit of time, increasing economic benefits. In industries such as coal mining and coal quarries, where large quantities of materials require long-distance, high-intensity transport, the application of steel cord conveyor belts makes transportation more efficient and stable, reducing operating costs and enhancing the market competitiveness of enterprises. Regarding safety performance, steel cord conveyor belts possess excellent flame-retardant and tear-resistant properties, providing reliable safety guarantees for industrial production. However, many locations using steel cord conveyor belts pose fire hazards. For example, underground coal mines are filled with flammable and explosive gases and coal dust. If the conveyor belt catches fire due to friction, overheating, or other reasons, it could potentially trigger a gas explosion and a large-scale fire, causing significant casualties and property damage. Meanwhile, ordinary conveyor belts release large amounts of toxic and harmful gases and smoke when burned, causing serious environmental pollution.

[0003] To overcome the shortcomings of the prior art, the present invention provides a steel wire rope core flame-retardant conveyor belt and its manufacturing process. Summary of the Invention

[0004] The purpose of this invention is to provide a steel wire rope core flame-retardant conveyor belt and its manufacturing process to solve the problems in the prior art.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0006] A manufacturing process for a steel wire rope core flame-retardant conveyor belt includes the following steps:

[0007] Step 1: Mix the mercapto-terminated flame retardant material with natural rubber and butadiene rubber in advance, and stir and react at 70-75℃ for 1-2 hours to obtain the reinforced flame retardant rubber material;

[0008] Step 2: Mix the reinforced flame-retardant rubber material, flame retardant, vulcanizing agent, accelerator, reinforcing agent, and antioxidant, and then plasticize, mix, and calender to obtain a rubber sheet; the rubber sheet includes an upper rubber sheet, a lower rubber sheet, and an intermediate rubber sheet;

[0009] Step 3: Using the steel wire rope core as the center, wrap the middle film around the steel wire rope core. Fiberglass cloth is attached to the upper and lower sides of the middle film, and the upper and lower films are set on the outermost sides. After cold pressing and vulcanization, the finished product is obtained.

[0010] In a more optimized manner, in step one, the content of each component of the enhanced flame-retardant rubber material is as follows: by mass parts, 60-80 parts natural rubber, 40-50 parts butadiene rubber, and 10-15 parts mercapto-terminated flame-retardant material.

[0011] The optimized preparation process of mercapto-terminated flame retardant materials is as follows:

[0012] S1: Under nitrogen atmosphere, eugenol is dissolved in tetrahydrofuran, and then triethylamine is added and stirred thoroughly to obtain an eugenol solution; hexachlorocyclotriphosphazene is dissolved in tetrahydrofuran to obtain a hexachlorocyclotriphosphazene solution; the eugenol solution is allowed to stand at 0-3℃ for 5-8 min, and then the hexachlorocyclotriphosphazene solution is added dropwise. After the addition is completed, the mixture is stirred at 25-30℃ for 2.5-3.5 h and then refluxed at 60-65℃ for 6-8 h. After the reaction is completed, the mixture is filtered, rotary evaporated, dissolved, washed, dried, and filtered again to obtain the intermediate product.

[0013] S2: Under nitrogen atmosphere, 2,2'-(1,2-ethylenedioxy)diethylthiol is dissolved in ethyl acetate to obtain reaction solution 1; the intermediate product and azobisisobutyronitrile are dissolved in ethyl acetate to obtain reaction solution 2; reaction solution 2 is added dropwise to reaction solution 1, and after the addition is complete, the mixture is reacted at 70-75℃ for 25-30h to obtain a mercapto-terminated flame retardant material.

[0014] In a more optimized manner, the reaction molar ratio of eugenol, triethylamine, and hexachlorocyclotriphosphazene during the preparation of the intermediate product is (6.5-7.0):4:1; and the reaction molar ratio of 2,2'-(1,2-ethylenedioxy)bis(ethanethiol) to the intermediate product during the preparation of the mercapto-capped flame retardant material is (6.3-6.5):1.

[0015] In a more optimized manner, in step two, the content of each component of the film is as follows (by mass): 110-145 parts of reinforcing flame-retardant rubber material, 20-25 parts of flame retardant, 3-4 parts of vulcanizing agent, 1-2 parts of accelerator, 40-60 parts of reinforcing agent, and 4-6 parts of antioxidant; wherein the vulcanizing agent is sulfur; the accelerator is zinc dibutyldithiocarbamate; the reinforcing agent is carbon black; and the antioxidant is N-phenyl-β-naphthylamine.

[0016] A more optimized preparation process for flame retardants is as follows:

[0017] S1: Under nitrogen atmosphere, eugenol is dissolved in tetrahydrofuran, and then triethylamine is added and stirred thoroughly to obtain an eugenol solution; octachloropropylsilsesquioxane is dissolved in tetrahydrofuran to obtain a siloxane solution; the eugenol solution is allowed to stand at 0-3℃ for 5-8 min, and then the siloxane solution is added dropwise. After the addition is completed, the mixture is stirred at 25-30℃ for 2.5-3.5 h and then refluxed at 65-70℃ for 6-8 h. After the reaction is completed, the mixture is filtered, rotary evaporated, dissolved, washed, dried, and filtered again to obtain the modified siloxane.

[0018] S2: Under nitrogen atmosphere, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 4-aminoacetophenone, aniline and p-toluenesulfonic acid are mixed and stirred and melted at 130-140℃ for 25-30h. After the reaction is completed, the mixture is precipitated, filtered, washed and vacuum dried to obtain the diaminophosphaphenanthrene material.

[0019] S3: Modified siloxane, diaminophosphaphenanthrene material, 4,4'-diaminodiphenylmethane, and melamine are added to N,N-dimethylformamide and heated to 80-90℃ for 20-30 minutes to dissolve, resulting in a mixture. The mixture is then reacted at 95-105℃ for 25-30 hours. After the reaction is completed, the mixture is cooled, filtered, washed, and vacuum dried to obtain the flame retardant.

[0020] In a more optimized manner, when preparing modified siloxanes, the reaction mass ratio of eugenol, triethylamine, and octachloropropylsilsesquioxane is 9:6:(13-15); when preparing bis(aminophosphaphenanthrene) materials, the reaction mass ratio of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 4-aminoacetophenone, aniline, and p-toluenesulfonic acid is (10-12):6:17:0.3; and when preparing flame retardants, the reaction mass ratio of modified siloxane, bis(aminophosphaphenanthrene) materials, 4,4'-diaminodiphenylmethane, and melamine is 14.4:(2.5-2.7):1:(1.3-1.5).

[0021] In a more optimized manner, in step three, the cold pressing parameters are: pressure of 2.0-2.5 MPa, time of 15-20 min, and temperature of 25-30℃; the vulcanization parameters are: temperature of 140-160℃ and time of 30-50 min.

[0022] The beneficial effects of this invention are:

[0023] The invention is characterized in that, in step one, a mercapto-terminated flame retardant material is obtained by adding eugenol, hexachlorocyclotriphosphazene, 2,2'-(1,2-ethylenedioxydioxo)diethylthiol, and azobisisobutyronitrile. The mercapto-terminated flame retardant material is pre-mixed with natural rubber and butadiene rubber, and reacted with stirring to obtain a reinforced flame-retardant rubber material. In this step, eugenol and hexachlorocyclotriphosphazene undergo a substitution reaction to obtain an intermediate product; then, the intermediate product introducing double bonds undergoes a mercapto-olefin click reaction with 2,2'-(1,2-ethylenedioxydioxo)diethylthiol to obtain the mercapto-terminated flame retardant material. Finally, the mercapto-terminated flame retardant material is pre-mixed with natural rubber and butadiene rubber, and a mercapto-olefin click reaction is carried out to obtain a reinforced flame-retardant rubber material with good flame retardant properties and uniform raw material dispersion.

[0024] The invention is characterized in that, in step two, a flame retardant is obtained by adding eugenol, octachloropropylsilsesquioxane, diaminophosphaphenanthrene, 4,4'-diaminodiphenylmethane, and melamine. The reinforcing flame-retardant rubber material, flame retardant, vulcanizing agent, accelerator, reinforcing agent, and antioxidant are mixed, and then plasticized, compounded, and calendered to obtain a rubber sheet. In this step, eugenol and octachloropropylsilsesquioxane undergo a substitution reaction to obtain a modified siloxane. By adjusting the mass ratio, this step ensures that the chlorine groups in the octachloropropylsilsesquioxane remain, i.e., a certain amount of chlorine groups remain on the surface of the modified siloxane. Then, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 4-aminoacetophenone, aniline, and p-toluenesulfonic acid are mixed and reacted to obtain a diaminophosphaphenanthrene material. The modified siloxane, diaminophosphaphenanthrene material, 4,4'-diaminodiphenylmethane, and melamine undergo a nucleophilic substitution reaction at a mass ratio of 14.4:(2.5-2.7):1:(1.3-1.5) to obtain a flame retardant with excellent flame retardant properties. Then, flame retardants with a certain amount of double bonds and other raw materials such as flame-retardant rubber materials are mixed (co-vulcanization can occur subsequently), and then plasticized, mixed, and calendered to obtain a rubber sheet; wherein the rubber sheet includes an upper rubber sheet, a lower rubber sheet, and an intermediate rubber sheet.

[0025] The key feature of this invention is that, in step three, the steel wire rope core is used as the center, and an intermediate film is wrapped around it. Fiberglass cloth is attached to the upper and lower sides of the intermediate film, and an upper and lower film are respectively placed on the outermost sides. After cold pressing and vulcanization, the finished product is obtained. The finished product prepared by this invention has excellent flame-retardant properties, and therefore has broad application prospects in the field of conveyor belt technology. Detailed Implementation

[0026] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0027] Raw material source:

[0028] Natural rubber, supplied by Lingshou County Jia'ao Mineral Products Co., Ltd., with a specification of 2-4mm; butadiene rubber, supplied by Dongguan Jiaqing Plastic Raw Materials Co., Ltd., with a viscosity of 50,000 molecular weight; octachloropropyl silsesquioxane, supplied by Shanghai Aladdin Biochemical Technology Co., Ltd., with a molecular weight of 1036; steel wire rope core, supplied by Nantong Changyuan Steel Rope Co., Ltd., with a diameter of 20mm; fiberglass cloth, supplied by Kunshan Zhoushi Quande Packaging Materials Business Department, with a thickness of 1mm and a strength of 1000N.

[0029] Example 1: Step 1: S1: Under nitrogen atmosphere, eugenol was dissolved in tetrahydrofuran, and then triethylamine was added. The mixture was stirred thoroughly to obtain an eugenol solution. Hexachlorocyclotriphosphazene was dissolved in tetrahydrofuran to obtain a hexachlorocyclotriphosphazene solution. The eugenol solution was allowed to stand at 3°C ​​for 8 min, and then the hexachlorocyclotriphosphazene solution was added dropwise. After the addition was completed, the mixture was stirred at 30°C for 3.5 h and then refluxed at 65°C for 8 h. After the reaction was completed, the mixture was filtered, rotary evaporated, dissolved, washed, dried, and filtered again to obtain the intermediate product. The molar ratio of eugenol, triethylamine, and hexachlorocyclotriphosphazene was 6.7:4:1.

[0030] S2: Under nitrogen atmosphere, 2,2'-(1,2-ethylenedioxydioxo)diethanethiol was dissolved in ethyl acetate to obtain reaction solution 1; the intermediate product and azobisisobutyronitrile were dissolved in ethyl acetate to obtain reaction solution 2; reaction solution 2 was added dropwise to reaction solution 1, and after the addition was completed, the mixture was reacted at 75℃ for 30 h to obtain a mercapto-terminated flame retardant material; the molar ratio of 2,2'-(1,2-ethylenedioxydioxo)diethanethiol to the intermediate product was 6.4:1;

[0031] S3: Mix 15 parts of mercapto-terminated flame retardant material with 80 parts of natural rubber and 50 parts of cis-butadiene rubber, and stir and react at 75°C for 2 hours to obtain reinforced flame retardant rubber material.

[0032] Step 2: S1: Under nitrogen atmosphere, eugenol is dissolved in tetrahydrofuran, then triethylamine is added and stirred thoroughly to obtain an eugenol solution; octachloropropylsilsesquioxane is dissolved in tetrahydrofuran to obtain a siloxane solution; the eugenol solution is allowed to stand at 3℃ for 8 min, then the siloxane solution is added dropwise. After the addition is complete, the mixture is stirred at 30℃ for 3.5 h and then refluxed at 70℃ for 8 h. After the reaction is complete, the mixture is filtered, rotary evaporated, dissolved, washed, dried, and filtered again to obtain the modified siloxane; the mass ratio of eugenol, triethylamine, and octachloropropylsilsesquioxane is 9:6:14.

[0033] S2: Under nitrogen atmosphere, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 4-aminoacetophenone, aniline, and p-toluenesulfonic acid were mixed and stirred and melted at 140℃ for 30 h. After the reaction, the mixture was precipitated, filtered, washed, and vacuum dried to obtain the bisaminophosphaphenanthrene material. The mass ratio of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 4-aminoacetophenone, aniline, and p-toluenesulfonic acid was 11:6:17:0.3.

[0034] S3: Modified siloxane, bis(aminophosphaphenanthrene) material, 4,4'-diaminodiphenylmethane, and melamine were added to N,N-dimethylformamide and heated at 90°C for 30 min to dissolve, obtaining a mixture. The mixture was then reacted at 105°C for 30 h. After the reaction was completed, the mixture was cooled, filtered, washed, and vacuum dried to obtain the flame retardant. The mass ratio of modified siloxane, bis(aminophosphaphenanthrene) material, 4,4'-diaminodiphenylmethane, and melamine was 14.4:2.6:1:1.4.

[0035] S4: Mix 145 parts of reinforced flame-retardant rubber material, 25 parts of flame retardant, 4 parts of sulfur, 2 parts of zinc dibutyldithiocarbamate, 60 parts of carbon black, and 6 parts of N-phenyl-β-naphthylamine, and then plasticize, mix, and calender to obtain a rubber sheet; the rubber sheet includes an upper rubber sheet, a lower rubber sheet, and an intermediate rubber sheet.

[0036] Step 3: Using the steel wire rope core as the center, wrap the intermediate film around the steel wire rope core. Fiberglass cloth is attached to the upper and lower sides of the intermediate film, and an upper film and a lower film are set on the outermost sides. Then, cold pressing and vulcanization are performed to obtain the finished product. The cold pressing parameters are: pressure 2.5MPa, time 20min, temperature 30℃; the vulcanization parameters are: temperature 160℃, time 50min.

[0037] Example 2: Step 1: S1: Under nitrogen atmosphere, eugenol was dissolved in tetrahydrofuran, and then triethylamine was added. The mixture was stirred thoroughly to obtain an eugenol solution. Hexachlorocyclotriphosphazene was dissolved in tetrahydrofuran to obtain a hexachlorocyclotriphosphazene solution. The eugenol solution was allowed to stand at 2°C for 7 min, and then the hexachlorocyclotriphosphazene solution was added dropwise. After the addition was completed, the mixture was stirred at 27°C for 2 h and then refluxed at 62°C for 7 h. After the reaction was completed, the mixture was filtered, rotary evaporated, dissolved, washed, dried, and filtered again to obtain the intermediate product. The molar ratio of eugenol, triethylamine, and hexachlorocyclotriphosphazene was 6.7:4:1.

[0038] S2: Under nitrogen atmosphere, 2,2'-(1,2-ethylenedioxydioxo)diethanethiol was dissolved in ethyl acetate to obtain reaction solution 1; the intermediate product and azobisisobutyronitrile were dissolved in ethyl acetate to obtain reaction solution 2; reaction solution 2 was added dropwise to reaction solution 1, and after the addition was completed, the mixture was reacted at 72℃ for 27 h to obtain a mercapto-terminated flame retardant material; the molar ratio of 2,2'-(1,2-ethylenedioxydioxo)diethanethiol to the intermediate product was 6.4:1;

[0039] S3: Mix 15 parts of mercapto-terminated flame retardant material with 80 parts of natural rubber and 50 parts of cis-butadiene rubber, and stir and react at 72°C for 1.5 hours to obtain reinforced flame retardant rubber material;

[0040] Step 2: S1: Under nitrogen atmosphere, eugenol is dissolved in tetrahydrofuran, then triethylamine is added and stirred thoroughly to obtain an eugenol solution; octachloropropylsilsesquioxane is dissolved in tetrahydrofuran to obtain a siloxane solution; the eugenol solution is allowed to stand at 2℃ for 7 min, then the siloxane solution is added dropwise. After the addition is complete, the mixture is stirred at 27℃ for 3 h and then refluxed at 67℃ for 7 h. After the reaction is complete, the mixture is filtered, rotary evaporated, dissolved, washed, dried, and filtered again to obtain the modified siloxane; the mass ratio of eugenol, triethylamine, and octachloropropylsilsesquioxane is 9:6:14.

[0041] S2: Under nitrogen atmosphere, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 4-aminoacetophenone, aniline, and p-toluenesulfonic acid were mixed and stirred and melted at 135℃ for 27 h. After the reaction, the mixture was precipitated, filtered, washed, and vacuum dried to obtain the bisaminophosphaphenanthrene material. The mass ratio of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 4-aminoacetophenone, aniline, and p-toluenesulfonic acid was 11:6:17:0.3.

[0042] S3: Modified siloxane, bis(aminophosphaphenanthrene) material, 4,4'-diaminodiphenylmethane, and melamine were added to N,N-dimethylformamide and heated to 85°C for 25 min to dissolve, obtaining a mixture. The mixture was then reacted at 100°C for 27 h. After the reaction was completed, the mixture was cooled, filtered, washed, and vacuum dried to obtain the flame retardant. The mass ratio of modified siloxane, bis(aminophosphaphenanthrene) material, 4,4'-diaminodiphenylmethane, and melamine was 14.4:2.6:1:1.4.

[0043] S4: Mix 145 parts of reinforced flame-retardant rubber material, 25 parts of flame retardant, 4 parts of sulfur, 2 parts of zinc dibutyldithiocarbamate, 60 parts of carbon black, and 6 parts of N-phenyl-β-naphthylamine, and then plasticize, mix, and calender to obtain a rubber sheet; the rubber sheet includes an upper rubber sheet, a lower rubber sheet, and an intermediate rubber sheet.

[0044] Step 3: Using the steel wire rope core as the center, wrap the middle film around the steel wire rope core. Fiberglass cloth is attached to the upper and lower sides of the middle film, and upper and lower films are set on the outermost sides. Then, cold pressing and vulcanization are performed to obtain the finished product. The cold pressing parameters are: pressure 2.3MPa, time 17min, temperature 27℃; the vulcanization parameters are: temperature 150℃, time 40min.

[0045] Example 3: Step 1: S1: Under nitrogen atmosphere, eugenol was dissolved in tetrahydrofuran, and then triethylamine was added. The mixture was stirred thoroughly to obtain an eugenol solution. Hexachlorocyclotriphosphazene was dissolved in tetrahydrofuran to obtain a hexachlorocyclotriphosphazene solution. The eugenol solution was allowed to stand at 0°C for 5 min, and then the hexachlorocyclotriphosphazene solution was added dropwise. After the addition was completed, the mixture was stirred at 25°C for 2.5 h and then refluxed at 60°C for 6 h. After the reaction was completed, the mixture was filtered, rotary evaporated, dissolved, washed, dried, and filtered again to obtain the intermediate product. The molar ratio of eugenol, triethylamine, and hexachlorocyclotriphosphazene was 6.7:4:1.

[0046] S2: Under nitrogen atmosphere, 2,2'-(1,2-ethylenedioxydioxo)diethanethiol was dissolved in ethyl acetate to obtain reaction solution 1; the intermediate product and azobisisobutyronitrile were dissolved in ethyl acetate to obtain reaction solution 2; reaction solution 2 was added dropwise to reaction solution 1, and after the addition was completed, the mixture was reacted at 70℃ for 25 h to obtain a mercapto-terminated flame retardant material; the molar ratio of 2,2'-(1,2-ethylenedioxydioxo)diethanethiol to the intermediate product was 6.4:1;

[0047] S3: Mix 15 parts of mercapto-terminated flame retardant material with 80 parts of natural rubber and 50 parts of cis-butadiene rubber, and stir and react at 70°C for 1 hour to obtain reinforced flame retardant rubber material.

[0048] Step 2: S1: Under nitrogen atmosphere, eugenol is dissolved in tetrahydrofuran, then triethylamine is added and stirred thoroughly to obtain an eugenol solution; octachloropropylsilsesquioxane is dissolved in tetrahydrofuran to obtain a siloxane solution; the eugenol solution is allowed to stand at 0℃ for 5 min, then the siloxane solution is added dropwise. After the addition is complete, the mixture is stirred at 25℃ for 2.5 h and then refluxed at 65℃ for 6 h. After the reaction is complete, the mixture is filtered, rotary evaporated, dissolved, washed, dried, and filtered again to obtain the modified siloxane; the mass ratio of eugenol, triethylamine, and octachloropropylsilsesquioxane is 9:6:14.

[0049] S2: Under nitrogen atmosphere, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 4-aminoacetophenone, aniline, and p-toluenesulfonic acid were mixed and stirred and melted at 130°C for 25 h. After the reaction, the mixture was precipitated, filtered, washed, and vacuum dried to obtain the bisaminophosphaphenanthrene material. The mass ratio of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 4-aminoacetophenone, aniline, and p-toluenesulfonic acid was 11:6:17:0.3.

[0050] S3: Modified siloxane, bis(aminophosphaphenanthrene) material, 4,4'-diaminodiphenylmethane, and melamine were added to N,N-dimethylformamide and heated at 80°C for 20 min to dissolve, obtaining a mixture. The mixture was then reacted at 95°C for 25 h. After the reaction was completed, the mixture was cooled, filtered, washed, and vacuum dried to obtain the flame retardant. The mass ratio of modified siloxane, bis(aminophosphaphenanthrene) material, 4,4'-diaminodiphenylmethane, and melamine was 14.4:2.6:1:1.4.

[0051] S4: Mix 145 parts of reinforced flame-retardant rubber material, 25 parts of flame retardant, 4 parts of sulfur, 2 parts of zinc dibutyldithiocarbamate, 60 parts of carbon black, and 6 parts of N-phenyl-β-naphthylamine, and then plasticize, mix, and calender to obtain a rubber sheet; the rubber sheet includes an upper rubber sheet, a lower rubber sheet, and an intermediate rubber sheet.

[0052] Step 3: Using the steel wire rope core as the center, wrap the middle film around the steel wire rope core. Fiberglass cloth is attached to the upper and lower sides of the middle film, and upper and lower films are set on the outermost sides. Then, cold pressing and vulcanization are performed to obtain the finished product. The cold pressing parameters are: pressure 2.0MPa, time 15min, temperature 25℃; the vulcanization parameters are: temperature 140℃, time 30min.

[0053] Comparative Example 1: The mercapto-capped flame retardant material was removed, and the rest was the same as in Example 1. The specific steps are as follows: Step 1: S1: Under nitrogen atmosphere, eugenol was dissolved in tetrahydrofuran, and then triethylamine was added. The mixture was stirred thoroughly to obtain an eugenol solution. Octachloropropylsilsesquioxane was dissolved in tetrahydrofuran to obtain a siloxane solution. The eugenol solution was allowed to stand at 3°C ​​for 8 minutes, and then the siloxane solution was added dropwise. After the addition was completed, the mixture was stirred at 30°C for 3.5 hours and then refluxed at 70°C for 8 hours. After the reaction was completed, the mixture was filtered, rotary evaporated, dissolved, washed, dried, and filtered again to obtain the modified siloxane. The mass ratio of eugenol, triethylamine, and octachloropropylsilsesquioxane was 9:6:14.

[0054] S2: Under nitrogen atmosphere, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 4-aminoacetophenone, aniline, and p-toluenesulfonic acid were mixed and stirred and melted at 140℃ for 30 h. After the reaction, the mixture was precipitated, filtered, washed, and vacuum dried to obtain the bisaminophosphaphenanthrene material. The mass ratio of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 4-aminoacetophenone, aniline, and p-toluenesulfonic acid was 11:6:17:0.3.

[0055] S3: Modified siloxane, bis(aminophosphaphenanthrene) material, 4,4'-diaminodiphenylmethane, and melamine were added to N,N-dimethylformamide and heated at 90°C for 30 min to dissolve, obtaining a mixture. The mixture was then reacted at 105°C for 30 h. After the reaction was completed, the mixture was cooled, filtered, washed, and vacuum dried to obtain the flame retardant. The mass ratio of modified siloxane, bis(aminophosphaphenanthrene) material, 4,4'-diaminodiphenylmethane, and melamine was 14.4:2.6:1:1.4.

[0056] S4: Mix 80 parts of natural rubber, 50 parts of butadiene rubber, 25 parts of flame retardant, 4 parts of sulfur, 2 parts of zinc dibutyldithiocarbamate, 60 parts of carbon black, and 6 parts of N-phenyl-β-naphthylamine, and then plasticize, mix, and calender to obtain a rubber sheet; the rubber sheet includes an upper rubber sheet, a lower rubber sheet, and an intermediate rubber sheet.

[0057] Step 2: Using the steel wire rope core as the center, wrap the intermediate film around the steel wire rope core. Fiberglass cloth is attached to the upper and lower sides of the intermediate film, and an upper film and a lower film are set on the outermost sides. Then, cold pressing and vulcanization are performed to obtain the finished product. The cold pressing parameters are: pressure 2.5MPa, time 20min, temperature 30℃; the vulcanization parameters are: temperature 160℃, time 50min.

[0058] Comparative Example 2: The flame retardant was removed, and the rest was the same as in Example 1. The specific steps are as follows: Step 1: S1: Under nitrogen atmosphere, eugenol was dissolved in tetrahydrofuran, and then triethylamine was added. The mixture was stirred thoroughly to obtain an eugenol solution. Hexachlorocyclotriphosphazene was dissolved in tetrahydrofuran to obtain a hexachlorocyclotriphosphazene solution. The eugenol solution was allowed to stand at 3°C ​​for 8 minutes, and then the hexachlorocyclotriphosphazene solution was added dropwise. After the addition was completed, the mixture was stirred at 30°C for 3.5 hours and then refluxed at 65°C for 8 hours. After the reaction was completed, the mixture was filtered, rotary evaporated, dissolved, washed, dried, and filtered again to obtain an intermediate product. The molar ratio of eugenol, triethylamine, and hexachlorocyclotriphosphazene was 6.7:4:1.

[0059] S2: Under nitrogen atmosphere, 2,2'-(1,2-ethylenedioxydioxo)diethanethiol was dissolved in ethyl acetate to obtain reaction solution 1; the intermediate product and azobisisobutyronitrile were dissolved in ethyl acetate to obtain reaction solution 2; reaction solution 2 was added dropwise to reaction solution 1, and after the addition was completed, the mixture was reacted at 75℃ for 30 h to obtain a mercapto-terminated flame retardant material; the molar ratio of 2,2'-(1,2-ethylenedioxydioxo)diethanethiol to the intermediate product was 6.4:1;

[0060] S3: Mix 15 parts of mercapto-terminated flame retardant material with 80 parts of natural rubber and 50 parts of cis-butadiene rubber, and stir and react at 75°C for 2 hours to obtain reinforced flame retardant rubber material.

[0061] Step 2: Mix 145 parts of reinforced flame-retardant rubber material, 4 parts of sulfur, 2 parts of zinc dibutyldithiocarbamate, 60 parts of carbon black, and 6 parts of N-phenyl-β-naphthylamine, and then plasticize, mix, and calender to obtain a rubber sheet; the rubber sheet includes an upper rubber sheet, a lower rubber sheet, and an intermediate rubber sheet.

[0062] Step 3: Using the steel wire rope core as the center, wrap the intermediate film around the steel wire rope core. Fiberglass cloth is attached to the upper and lower sides of the intermediate film, and an upper film and a lower film are set on the outermost sides. Then, cold pressing and vulcanization are performed to obtain the finished product. The cold pressing parameters are: pressure 2.5MPa, time 20min, temperature 30℃; the vulcanization parameters are: temperature 160℃, time 50min.

[0063] Comparative Example 3: The mercapto-capped flame retardant material and flame retardant were removed, and the rest was the same as in Example 1. The specific steps are as follows: Step 1: 80 parts of natural rubber, 50 parts of cis-butadiene rubber, 4 parts of sulfur, 2 parts of zinc dibutyldithiocarbamate, 60 parts of carbon black, and 6 parts of N-phenyl-β-naphthylamine were mixed, and then plasticized, mixed, and calendered to obtain a rubber sheet; the rubber sheet includes an upper rubber sheet, a lower rubber sheet, and an intermediate rubber sheet;

[0064] Step 2: Using the steel wire rope core as the center, wrap the intermediate film around the steel wire rope core. Fiberglass cloth is attached to the upper and lower sides of the intermediate film, and an upper film and a lower film are set on the outermost sides. Then, cold pressing and vulcanization are performed to obtain the finished product. The cold pressing parameters are: pressure 2.5MPa, time 20min, temperature 30℃; the vulcanization parameters are: temperature 160℃, time 50min.

[0065] Testing and experimentation:

[0066] Limiting oxygen index test: Referring to GB / T 10707-2008 "Determination of the flammability of rubber", the rubber sheet prepared by this invention was used as the sample. The sample size was 80×6.5×3mm, and the oxygen index value was recorded.

[0067] Vertical burning test: Referring to GB / T 10707-2008 "Determination of the flammability of rubber", the rubber sheet prepared in this invention was used as a sample with a sample size of 125×13×3mm to determine the vertical burning rating.

[0068] Tensile strength test: Referring to GB / T 528-2009 "Determination of Tensile Stress-Strain Properties of Vulcanized Rubber or Thermoplastic Rubber", the rubber sheet prepared according to this invention was used as the sample. The sample dimensions were: length 120 mm, end width 25 mm, narrow portion width 6 mm, narrow portion length 35 mm, and thickness 2 mm. The tensile strength of the sample was tested. The results are shown in the table below:

[0069]

[0070] Conclusion: The dosages in Examples 1-3 remained unchanged, with only some reaction parameters modified. Experimental data show that the various properties of the samples did not exhibit significant fluctuations.

[0071] Comparative Example 1: The mercapto-terminated flame retardant material was removed, and the rest was the same as in Example 1. The experimental data showed that, compared with Example 1, the oxygen index decreased to 29% and the tensile strength decreased to 21.1 MPa. The reason for this is that the mercapto-terminated flame retardant material contains a variety of flame retardant elements, such as phosphorus and nitrogen, which can synergistically retard flame. Therefore, removing the mercapto-terminated flame retardant material reduced the flame retardant performance.

[0072] Comparative Example 2: The flame retardant was removed, and the rest was the same as in Example 1. The experimental data showed that, compared with Example 1, the oxygen index decreased to 24% and the tensile strength decreased to 20.8 MPa. The reason for this is that the flame retardant contains a variety of flame retardant structures and flame retardant elements (phosphorus, nitrogen, silicon). Therefore, after removing it, the oxygen index and tensile strength decreased.

[0073] Comparative Example 3: The mercapto-terminated flame retardant material and flame retardant were removed, and the rest was the same as in Example 1. The experimental data showed that, compared with Example 1, the oxygen index decreased to 20% and the tensile strength decreased to 20.2 MPa. The reason for this is that, as can be seen from Comparative Examples 1 and 2, the mercapto-terminated flame retardant material and flame retardant have excellent flame retardant properties. Therefore, removing them significantly reduced the flame retardant properties.

[0074] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process method article or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process method article or apparatus.

[0075] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A manufacturing process for a steel wire rope core flame-retardant conveyor belt, characterized in that: Includes the following steps: Step 1: Mix the mercapto-terminated flame retardant material with natural rubber and butadiene rubber in advance, and stir and react at 70-75℃ for 1-2 hours to obtain the reinforced flame retardant rubber material; the content of each component of the reinforced flame retardant rubber material is as follows: by mass parts, 60-80 parts natural rubber, 40-50 parts butadiene rubber, and 10-15 parts mercapto-terminated flame retardant material. The preparation process of mercapto-terminated flame retardant materials is as follows: S1: Under nitrogen atmosphere, eugenol is dissolved in tetrahydrofuran, and then triethylamine is added and stirred thoroughly to obtain an eugenol solution; hexachlorocyclotriphosphazene is dissolved in tetrahydrofuran to obtain a hexachlorocyclotriphosphazene solution; the eugenol solution is allowed to stand at 0-3℃ for 5-8 min, and then hexachlorocyclotriphosphazene solution is added dropwise. After the addition is completed, the mixture is stirred at 25-30℃ for 2.5-3.5 h and then refluxed at 60-65℃ for 6-8 h. After the reaction is completed, the mixture is filtered, rotary evaporated, dissolved, washed, dried, and filtered again to obtain the intermediate product; when preparing the intermediate product, the molar ratio of eugenol, triethylamine, and hexachlorocyclotriphosphazene is (6.5-7.0):4:1; S2: Under nitrogen atmosphere, 2,2'-(1,2-ethylenedioxydioxo)diethanethiol is dissolved in ethyl acetate to obtain reaction solution 1; the intermediate product and azobisisobutyronitrile are dissolved in ethyl acetate to obtain reaction solution 2; reaction solution 2 is added dropwise to reaction solution 1, and after the addition is complete, the mixture is reacted at 70-75℃ for 25-30 h to obtain a mercapto-terminated flame retardant material; when preparing the mercapto-terminated flame retardant material, the molar ratio of 2,2'-(1,2-ethylenedioxydioxo)diethanethiol to the intermediate product is (6.3-6.5):1; Step 2: Mix the reinforced flame-retardant rubber material, flame retardant, vulcanizing agent, accelerator, reinforcing agent, and antioxidant, and then plasticize, mix, and calender to obtain a rubber sheet; the rubber sheet includes an upper rubber sheet, a lower rubber sheet, and an intermediate rubber sheet; Step 3: Using the steel wire rope core as the center, wrap the middle film around the steel wire rope core. Fiberglass cloth is attached to the upper and lower sides of the middle film, and the upper and lower films are set on the outermost sides. After cold pressing and vulcanization, the finished product is obtained.

2. The manufacturing process of a steel wire rope core flame-retardant conveyor belt according to claim 1, characterized in that: In step two, the composition of each component of the film is as follows (by mass): 110-145 parts of reinforcing flame-retardant rubber material, 20-25 parts of flame retardant, 3-4 parts of vulcanizing agent, 1-2 parts of accelerator, 40-60 parts of reinforcing agent, and 4-6 parts of antioxidant; the vulcanizing agent is sulfur; the accelerator is zinc dibutyldithiocarbamate; the reinforcing agent is carbon black; and the antioxidant is N-phenyl-β-naphthylamine.

3. The manufacturing process of a steel wire rope core flame-retardant conveyor belt according to claim 2, characterized in that: The preparation process of flame retardants is as follows: S1: Under nitrogen atmosphere, eugenol is dissolved in tetrahydrofuran, and then triethylamine is added and stirred thoroughly to obtain an eugenol solution; octachloropropylsilsesquioxane is dissolved in tetrahydrofuran to obtain a siloxane solution; the eugenol solution is allowed to stand at 0-3℃ for 5-8 min, and then the siloxane solution is added dropwise. After the addition is completed, the mixture is stirred at 25-30℃ for 2.5-3.5 h and then refluxed at 65-70℃ for 6-8 h. After the reaction is completed, the mixture is filtered, rotary evaporated, dissolved, washed, dried, and filtered again to obtain the modified siloxane. S2: Under nitrogen atmosphere, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 4-aminoacetophenone, aniline and p-toluenesulfonic acid are mixed and stirred and melted at 130-140℃ for 25-30h. After the reaction is completed, the mixture is precipitated, filtered, washed and vacuum dried to obtain the diaminophosphaphenanthrene material. S3: Modified siloxane, diaminophosphaphenanthrene material, 4,4'-diaminodiphenylmethane, and melamine are added to N,N-dimethylformamide and heated to dissolve at 80-90℃ for 20-30 minutes to obtain a mixture. The mixture is then reacted at a constant temperature of 95-105℃ for 25-30 hours. After the reaction is completed, the mixture is cooled, filtered, washed, and vacuum dried to obtain the flame retardant.

4. The manufacturing process of a steel wire rope core flame-retardant conveyor belt according to claim 3, characterized in that: When preparing modified siloxanes, the reaction mass ratio of eugenol, triethylamine, and octachloropropylsilsesquioxane is 9:6:(13-15); when preparing bis(aminophosphaphenanthrene) materials, the reaction mass ratio of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 4-aminoacetophenone, aniline, and p-toluenesulfonic acid is (10-12):6:17:0.3; when preparing flame retardants, the reaction mass ratio of modified siloxane, bis(aminophosphaphenanthrene) materials, 4,4'-diaminodiphenylmethane, and melamine is 14.4:(2.5-2.7):1:(1.3-1.5).

5. The manufacturing process of a steel wire rope core flame-retardant conveyor belt according to claim 1, characterized in that: In step three, the cold pressing parameters are: pressure 2.0-2.5MPa, time 15-20min, and temperature 25-30℃; the vulcanization parameters are: temperature 140-160℃ and time 30-50min.

6. A flame-retardant conveyor belt with a steel wire rope core, characterized in that, Prepared according to any one of the preparation processes described in claims 1-5.

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