A flame-retardant aramid core solid woven conveyor belt and its preparation method

Abstract

This invention belongs to the field of flame-retardant conveyor belt technology, specifically relating to an aramid core solid flame-retardant conveyor belt and its preparation method. The aramid core solid flame-retardant conveyor belt includes a cover rubber, a single layer of aramid fiber cloth, and an adhesive layer. The cover rubber, by weight, comprises: 90-110 parts rubber, 4-6 parts hydroxyl-containing epoxy resin, 35-45 parts modified filler, 10-20 parts flame retardant, 4-6 parts zinc oxide, 1-5 parts antioxidant, 1-5 parts accelerator, 1-3 parts sulfur, and 1-3 parts stearic acid. The rubber includes styrene-butadiene rubber, neodymium-based cis-butadiene rubber, natural rubber, and fluororubber. The aramid core solid flame-retardant conveyor belt provided by this invention exhibits excellent cold resistance, wear resistance, flame retardancy, hydrophobicity, and adhesive strength.

Description

Technical Field

[0001] This invention belongs to the field of flame-retardant conveyor belt technology, specifically relating to an aramid core solid flame-retardant conveyor belt and its preparation method. Background Technology

[0002] Material transportation is a crucial link in the development of various industries, and conveyor belts are an important component of material transportation. In the coal mining and chemical industries, because the materials are flammable and explosive, conveyor belts are required to have good flame-retardant properties to prevent fire accidents.

[0003] Currently, the conveyor belts used in coal mines are mainly solid-woven flame-retardant conveyor belts and steel cord flame-retardant conveyor belts. Compared with steel cord flame-retardant conveyor belts, solid-woven flame-retardant conveyor belts are lighter and more widely used. Traditional solid-woven flame-retardant conveyor belts primarily use nylon, polyester, and cotton fibers as the integral belt core. However, these materials have low strength, requiring multi-layer weaving structures to achieve good strength. This makes impregnation with slurry difficult, affecting the conveyor belt's performance and thus limiting its application.

[0004] Aramid fibers possess advantages such as high strength and modulus, light weight, flame retardancy, and high temperature resistance, making them an ideal skeleton material for high-performance conveyor belts. Traditional aramid-core solid flame-retardant conveyor belts typically consist of a cover layer, an aramid core, and an impregnated rubber / adhesive layer, as illustrated in patent publication number CN 107216560. Chinese patent B discloses a flame-retardant conveyor belt made of aramid fabric and its manufacturing method. The conveyor belt includes a cover layer, an integral aramid fabric core, and a core impregnation compound. The cover layer uses a PVC / CM / TPU blend thermoplastic elastomer, which has good flame retardant properties, high tensile strength, excellent elasticity, good wear resistance, and high adhesion strength to the impregnated integral core. The integral fabric core has a three-layer structure, with radial stress lines made of aramid fibers, resulting in high strength, a thin belt body, and light weight, significantly reducing energy consumption during conveyor belt operation. The core impregnation compound contains MDI tackifier, which greatly improves the adhesion strength between the plasticized integral core and the cover layer, ensuring the conveyor belt does not delaminate during long-term operation. This solution uses vacuum impregnation of the integral core, extrusion molding, and dynamic vulcanization to produce the conveyor belt, resulting in a simple process, low energy consumption, and high production efficiency. However, the cover layer and core impregnation compound in this technical solution mainly use polyvinyl chloride resin as the main component, and polyvinyl chloride resin has poor cold resistance, limiting its use in cold environments.

[0005] Chinese Patent Publication No. CN 117681515 A discloses an environmentally friendly flame-retardant aramid rope conveyor belt and its preparation method. This environmentally friendly flame-retardant aramid rope conveyor belt comprises, from top to bottom, a cover rubber, a core rubber layer, an aramid rope, a core rubber layer, and a cover rubber layer. The cover rubber layer comprises chloroprene rubber, modified chlorosulfonated polyethylene rubber, carbon black, activated glass fiber powder, decabromodiphenyl ether, zinc oxide, zinc borate, magnesium oxide, stearic acid, antioxidant, accelerator, and sulfur. The core rubber layer comprises chloroprene rubber, natural rubber, molybdenum-based high-vinyl polybutadiene rubber, zinc oxide, stearic acid, sulfur, adhesive, accelerator, antioxidant, and coumarone. This technical solution, through the matching and synergy of various systems, ensures the tensile strength, wear resistance, impact resistance, flame retardant and antistatic properties of the rubber compound, as well as the coordination of the components within the core, thereby manufacturing an environmentally friendly flame-retardant aramid rope conveyor belt with excellent comprehensive performance. However, the wear rate in this technical solution is 140mm. 3 The wear and tear was significant, and no attention was paid to cold resistance. Summary of the Invention

[0006] The purpose of this invention is to overcome the problem that the cold resistance and wear resistance of existing aramid core solid flame-retardant conveyor belts need to be improved. The invention provides an aramid core solid flame-retardant conveyor belt in which styrene-butadiene rubber, neodymium-based cis-butadiene rubber, natural rubber and fluororubber are used in the cover rubber, and light calcium carbonate and silica are modified with fluorinated siloxanes and diisocyanates. The resulting aramid core solid flame-retardant conveyor belt has excellent cold resistance, wear resistance, flame retardancy, hydrophobicity and bonding strength.

[0007] Another object of the present invention is to provide a method for preparing an aramid core solid flame-retardant conveyor belt.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] This invention provides an aramid core solid flame-retardant conveyor belt, comprising a cover rubber, a single layer of aramid fiber cloth, and an adhesive layer;

[0010] The covering adhesive, by weight, comprises the following raw materials: 90-110 parts rubber, 4-6 parts hydroxyl-containing epoxy resin, 35-45 parts modified filler, 10-20 parts flame retardant, 4-6 parts zinc oxide, 1-5 parts antioxidant, 1-5 parts accelerator, 1-3 parts sulfur, and 1-3 parts stearic acid.

[0011] The rubbers mentioned include styrene-butadiene rubber, neodymium-based cis-butadiene rubber, natural rubber, and fluororubber.

[0012] Furthermore, the mass ratio of the styrene-butadiene rubber, neodymium-based cis-butadiene rubber, natural rubber, and fluororubber is 3-5:1-2:1-2:1, and more preferably 4:1:1:1.

[0013] Furthermore, the neodymium-based cis-butadiene rubber contains ≥96% cis-1,4-polybutadiene.

[0014] Furthermore, the fluororubber is a fluororubber composed of a copolymer of vinylidene fluoride, tetrafluoroethylene, and perfluoroalkyl vinyl ether.

[0015] Furthermore, the fluorine content of the fluororubber is 64-66 wt%.

[0016] Furthermore, the raw materials for the modified filler include light calcium carbonate, silica, fluorosiloxane, and diisocyanate.

[0017] Furthermore, the fluorinated siloxane contains 13 fluorine atoms.

[0018] Furthermore, the fluorinated siloxane is tridecafluorooctyltriethoxysilane.

[0019] Furthermore, the diisocyanate is selected from at least one of toluene diisocyanate, diphenylmethane diisocyanate, and isophorone diisocyanate, preferably toluene diisocyanate or diphenylmethane diisocyanate, and most preferably toluene diisocyanate.

[0020] Furthermore, the mass ratio of the light calcium carbonate, fumed silica, perfluoroalkylsiloxane and diisocyanate is 20-30:5-20:0.5-2:2-5.

[0021] Furthermore, the mass ratio of the light calcium carbonate, fumed silica, perfluoroalkylsiloxane and diisocyanate is 20:10:1.8:3.

[0022] Furthermore, the light calcium carbonate comprises rose-cluster-shaped light calcium carbonate and rice-grain-shaped light calcium carbonate in a mass ratio of 4-8:3-5.

[0023] Furthermore, the light calcium carbonate comprises rose-shaped light calcium carbonate and rice-grain-shaped light calcium carbonate in a mass ratio of 6:3.

[0024] Furthermore, the preparation method of the modified filler includes the following steps: dispersing light calcium carbonate, silica and fluorinated siloxane in an aqueous ethanol solution, performing a first ultrasonic reaction, and then filtering, washing and drying to obtain an intermediate product; dispersing the intermediate product and diisocyanate in an organic solvent, performing a second ultrasonic reaction, and then filtering, washing and drying to obtain the modified filler.

[0025] Furthermore, the ratio of the total mass of the ethanol aqueous solution to light calcium carbonate and precipitated silica is 1g:20-40mL.

[0026] Furthermore, the mass concentration of the ethanol aqueous solution is 70-80%.

[0027] Furthermore, the organic solvent is selected from at least one of dimethyl sulfoxide and dimethylformamide.

[0028] Furthermore, the ratio of the intermediate product to the organic solvent is 1g:20-40mL.

[0029] Furthermore, the temperature of the first ultrasonic reaction is 25-35℃, and the time is 1-2 hours.

[0030] Furthermore, the temperature of the second ultrasonic reaction is 25-35℃, and the time is 1-2 hours.

[0031] Furthermore, the flame retardant is selected from at least one of zinc borate, magnesium hydroxide, aluminum hydroxide, ammonium polyphosphate, and red phosphorus.

[0032] Furthermore, the flame retardant is a mixture of magnesium hydroxide and aluminum hydroxide.

[0033] Furthermore, the mass ratio of magnesium hydroxide to aluminum hydroxide is 1-3:1-3, preferably 1:1.

[0034] Furthermore, the adhesive, by weight, comprises the following raw materials: 40-65 parts chloroprene rubber, 15-25 parts natural rubber, 10-20 parts styrene-butadiene rubber, 10-15 parts bio-based itaconic acid ester rubber, 10-15 parts adhesive, 8-12 parts silica, 2-4 parts zinc oxide, 1-3 parts antioxidant, 1-3 parts accelerator, and 1-3 parts sulfur.

[0035] Furthermore, the adhesive is selected from at least one of adhesive ADA, adhesive RS, and adhesive RF-90.

[0036] Furthermore, the accelerator is selected from at least one of dibenzothiazole disulfide, dimethyl disulfide carbonyl dimethylamine, and N-cyclohexyl-2-benzothiazole sulfenamide.

[0037] Furthermore, the antioxidant is selected from at least one of 2,6-bis-tert-butyl-p-cresol, N-isopropyl-N'-phenyl-o-phenylenediamine, and N-cyclohexyl-N'-phenyl-p-phenylenediamine.

[0038] Furthermore, the aramid core solid flame-retardant conveyor belt of the present invention comprises, from top to bottom, a cover rubber, a backing rubber, a single layer of aramid fiber cloth, a backing rubber, and a cover rubber.

[0039] Furthermore, the thickness ratio of the cover adhesive, the adhesive layer, the single-layer aramid fiber cloth, the adhesive layer, and the cover adhesive, from top to bottom, is 10-15:1:2-4:1:4-6.

[0040] Furthermore, the thickness ratio of the cover adhesive, the adhesive layer, the single-layer aramid fiber cloth, the adhesive layer, and the cover adhesive, from top to bottom, is 12:1:3:1:6.

[0041] This invention also provides a method for preparing the above-mentioned aramid core solid flame-retardant conveyor belt, comprising the following steps:

[0042] (1) Preparation of cover rubber: Rubber is first mixed, hydroxyl epoxy resin, modified filler, flame retardant, zinc oxide, antioxidant and stearic acid are added for second mixing, accelerator and sulfur are added for third mixing, and calendering is performed after the third mixing to obtain cover rubber.

[0043] (2) Preparation of adhesive: Chloroprene rubber, natural rubber, styrene-butadiene rubber and bio-based itaconic acid ester rubber are first mixed, then adhesive, silica, zinc oxide and antioxidant are added for second mixing, then sulfur and accelerator are added for third mixing, and after the third mixing is completed, calendering is performed to obtain adhesive.

[0044] (3) After stacking the layers in the following order from top to bottom—cover rubber, adhesive, single-layer aramid fiber cloth, adhesive and cover rubber—vulcanization is performed to obtain the aramid core solid flame retardant conveyor belt.

[0045] Furthermore, in the preparation process of the cover adhesive and the bonding adhesive, the first mixing temperature is 100-110℃ and the mixing time is 1-3 min; the second mixing temperature is 95-105℃ and the mixing time is 3-5 min; the third mixing temperature is 70-80℃ and the mixing time is 2-5 min.

[0046] Furthermore, the calendering temperature during the preparation of the cover adhesive and the bonding adhesive is 90-100℃.

[0047] Furthermore, the vulcanization temperature is 145-155℃, and the vulcanization time is 25-35 minutes.

[0048] Compared with the prior art, the present invention has the following beneficial effects:

[0049] 1. In this invention, the rubber in the cover rubber includes styrene-butadiene rubber, neodymium-based cis-butadiene rubber, natural rubber, and fluororubber. Combined with flame retardants, it forms a high-density cross-linked network after vulcanization. The resulting aramid core solid flame-retardant conveyor belt not only has excellent flame retardancy and wear resistance, but also excellent flexibility at low temperatures. In particular, the combination of specific neodymium-based cis-butadiene rubber and specific fluororubber enables the aramid core solid flame-retardant conveyor belt to still have a high tensile cold resistance coefficient at -50℃. At the same time, the styrene-butadiene rubber, neodymium-based cis-butadiene rubber, natural rubber, and fluororubber in the cover rubber of this invention work together with the bio-based itaconic acid ester rubber in the adhesive to achieve excellent adhesion strength between the cover rubber and the single-layer aramid fiber cloth.

[0050] 2. Freshly mined coal contains a certain amount of moisture on its surface, which easily freezes and adheres to the conveyor belt surface under cold conditions. A conveyor belt with good hydrophobicity can avoid this phenomenon to some extent. Although the fluororubber in the cover rubber of this invention gives the aramid core solid flame-retardant conveyor belt good cold resistance and a certain degree of hydrophobicity, the hydrophobic effect is poor. Therefore, this invention creatively uses fluorosiloxanes and diisocyanates to modify light calcium carbonate and silica, resulting in an aramid core solid flame-retardant conveyor belt with excellent hydrophobic properties. The modified light calcium carbonate... Calcium carbonate and silica contain fluorine and isocyanate groups on their surfaces. During the preparation of the cover rubber, the fluorine groups accumulate on the surface of the cover rubber and work together with specific fluorinated resins to form a continuous fluorinated layer, improving hydrophobic properties. The cross-linking of isocyanate groups and hydroxyl-containing epoxy resins ensures the stable existence of light calcium carbonate and silica in the system. The inventors also unexpectedly discovered that using rose-cluster-shaped and rice-grain-shaped light calcium carbonate can further reduce the wear of aramid core solid flame-retardant conveyor belts and improve the tensile cold resistance coefficient of aramid core solid flame-retardant conveyor belts. Detailed Implementation

[0051] To provide a clearer understanding of the technical features, objectives, and effects of this invention, specific implementation schemes are now described in detail.

[0052] The present invention will be further described below with reference to embodiments, but the present invention is not limited to the following embodiments. The implementation conditions used in the embodiments can be further adjusted according to different requirements of specific use, and the implementation conditions not specified are conventional conditions in the industry. The technical features involved in the various embodiments of the present invention can be combined with each other as long as they do not conflict with each other.

[0053] Unless otherwise specified, all raw materials used in the following examples and comparative examples are commercially available or prepared by conventional methods in the art.

[0054] Table 1 shows examples of the sources of the raw materials used in the following examples and comparative examples:

[0055] Table 1

[0056]

[0057] Example 1: An aramid core solid flame-retardant conveyor belt, consisting of, from top to bottom, a cover rubber, a backing rubber, a single layer of aramid fiber cloth, a backing rubber, and a cover rubber;

[0058] The covering adhesive, by weight, consists of 90 parts rubber, 4 parts hydroxyl-containing epoxy resin, 38 parts modified filler, 12 parts flame retardant, 4 parts zinc oxide, 2 parts antioxidant, 2 parts accelerator, 1 part sulfur, and 1 part stearic acid.

[0059] The rubber is composed of styrene-butadiene rubber, neodymium-based cis-butadiene rubber, natural rubber, and fluororubber A in a mass ratio of 4:1:1:1.

[0060] The modified filler is composed of light calcium carbonate, silica, tridecafluorooctyltriethoxysilane and toluene diisocyanate in a mass ratio of 20:10:1.8:3.

[0061] The light calcium carbonate is composed of rose-shaped light calcium carbonate and rice-grain-shaped light calcium carbonate in a mass ratio of 6:3.

[0062] The modified filler is prepared by dispersing light calcium carbonate, fumed silica and fluorinated siloxane in an ethanol aqueous solution, performing a first ultrasonic reaction, and then filtering, washing and drying to obtain an intermediate product; dispersing the intermediate product and diisocyanate in dimethylformamide, performing a second ultrasonic reaction, and then filtering, washing and drying to obtain the modified filler.

[0063] The ratio of the total mass of the ethanol aqueous solution to light calcium carbonate and precipitated silica is 1 g: 30 mL.

[0064] The mass concentration of the ethanol aqueous solution is 70%.

[0065] The ratio of the intermediate product to the organic solvent is 1 g: 30 mL.

[0066] The temperature of the first ultrasonic reaction was 25°C, and the time was 1 hour.

[0067] The temperature of the second ultrasonic reaction was 25°C, and the time was 1 hour.

[0068] The flame retardant is a mixture of magnesium hydroxide and aluminum hydroxide.

[0069] The mass ratio of magnesium hydroxide to aluminum hydroxide is 1:1.

[0070] The adhesive, by weight, consists of 45 parts chloroprene rubber, 20 parts natural rubber, 20 parts styrene-butadiene rubber, 15 parts bio-based itaconic acid ester rubber, 10 parts ADA adhesive, 8 parts silica, 2 parts zinc oxide, 1 part antioxidant, 1 part accelerator, and 1 part sulfur.

[0071] The accelerator mentioned in the cover adhesive and the bonding adhesive is dibenzothiazole disulfide.

[0072] The antioxidant mentioned in the cover adhesive and the bonding adhesive is 2,6-bis-tert-butyl-p-cresol.

[0073] The thickness ratio of the cover adhesive, the adhesive layer, the single-layer aramid fiber cloth, the adhesive layer, and the cover adhesive, from top to bottom, is 12:1:3:1:6.

[0074] The preparation method of the above-mentioned aramid core solid flame-retardant conveyor belt includes the following steps:

[0075] (1) Preparation of cover rubber: Rubber is first mixed at 100°C for 2 minutes, hydroxyl epoxy resin, modified filler, flame retardant, zinc oxide, antioxidant and stearic acid are added and second mixed at 95°C for 4 minutes, accelerator and sulfur are added and third mixed at 80°C for 3 minutes, after the third mixing is completed, calendering is performed at 100°C to obtain cover rubber.

[0076] (2) Preparation of adhesive: Chloroprene rubber, natural rubber, styrene-butadiene rubber and bio-based itaconic acid ester rubber are first mixed at 100°C for 2 minutes, then adhesive, silica, zinc oxide and antioxidant are added and mixed at 100°C for 3 minutes, then sulfur and accelerator are added and mixed at 80°C for 2 minutes. After the third mixing, the mixture is calendered at 100°C to obtain the adhesive.

[0077] (3) After stacking the layers in the following order from top to bottom: cover rubber, adhesive, single-layer aramid fiber cloth, adhesive and cover rubber, vulcanize at 150°C for 30 minutes to obtain the aramid core flame retardant conveyor belt.

[0078] Example 2: A flame-retardant conveyor belt with aramid core

[0079] The specific implementation method is the same as in Example 1, except that the covering adhesive, by weight, is composed of 100 parts rubber, 5 parts hydroxyl-containing epoxy resin, 42 parts modified filler, 16 parts flame retardant, 5 parts zinc oxide, 3 parts antioxidant, 3 parts accelerator, 2 parts sulfur, and 2 parts stearic acid.

[0080] The preparation method of the aramid core solid flame-retardant conveyor belt is the same as in Example 1.

[0081] Example 3: A flame-retardant conveyor belt with aramid core

[0082] The specific implementation method is the same as in Example 1, except that the covering adhesive, by weight, is composed of 110 parts rubber, 6 parts hydroxyl-containing epoxy resin, 45 parts modified filler, 20 parts flame retardant, 6 parts zinc oxide, 5 parts antioxidant, 5 parts accelerator, 3 parts sulfur, and 3 parts stearic acid.

[0083] The preparation method of the aramid core solid flame-retardant conveyor belt is the same as in Example 1.

[0084] Comparative Example 1: A Flame-Retardant Conveyor Belt with Aramid Core

[0085] The specific implementation method is the same as in Example 2, except that the neodymium-based cis-butadiene rubber is replaced with an equal mass of titanium-based cis-butadiene rubber.

[0086] The preparation method of the aramid core solid flame-retardant conveyor belt is the same as in Example 2.

[0087] Comparative Example 2: A Flame-Retardant Conveyor Belt with Aramid Core

[0088] The specific implementation method is the same as in Example 2, except that fluororubber A is replaced with fluororubber B of the same mass.

[0089] The preparation method of the aramid core solid flame-retardant conveyor belt is the same as in Example 2.

[0090] Comparative Example 3: A Flame-Retardant Conveyor Belt with Aramid Core

[0091] The specific implementation method is the same as in Example 2, except that the hydroxyl-containing epoxy resin is replaced with an equal mass of fluororubber A.

[0092] The preparation method of the aramid core solid flame-retardant conveyor belt is the same as in Example 2.

[0093] Comparative Example 4: A Flame-Retardant Conveyor Belt with Aramid Core

[0094] The specific implementation method is the same as in Example 2, except that the raw materials of the modified filler are composed of light calcium carbonate, fumed silica and tridecafluorooctyltriethoxysilane in a mass ratio of 20:10:1.8.

[0095] The modified filler is prepared by dispersing light calcium carbonate, fumed silica and fluorinated siloxane in an aqueous ethanol solution, performing a first ultrasonic reaction, and then filtering, washing and drying the mixture to obtain the final product.

[0096] The preparation method of the aramid core solid flame-retardant conveyor belt is the same as in Example 2.

[0097] Comparative Example 5: A Flame-Retardant Conveyor Belt with Aramid Core

[0098] The specific implementation method is the same as in Example 2, except that the raw materials of the modified filler are composed of light calcium carbonate, fumed silica and toluene diisocyanate in a mass ratio of 20:10:3.

[0099] The modified filler is prepared by dispersing light calcium carbonate, fumed silica and diisocyanate in dimethylformamide, performing a second ultrasonic reaction, and then filtering, washing and drying the mixture to obtain the modified filler.

[0100] The preparation method of the aramid core solid flame-retardant conveyor belt is the same as in Example 2.

[0101] Comparative Example 6

[0102] The specific implementation method is the same as in Example 2, except that the light calcium carbonate is composed of spindle-shaped light calcium carbonate and rhombohedral light calcium carbonate in a mass ratio of 6:3.

[0103] The preparation method of the aramid core solid flame-retardant conveyor belt is the same as in Example 2.

[0104] Test case

[0105] The aramid core solid flame-retardant conveyor belts prepared in Examples 1-3 and Comparative Examples 1-6 were tested for wear, adhesion strength between the cover rubber and the single-layer aramid fiber cloth, and alcohol torch burning according to MT914-2008 standard; the tensile cold resistance coefficient was determined according to HG / T3867-2006 standard; and the water contact angle of the surface of the aramid core solid flame-retardant conveyor belt was tested using a water contact angle measuring instrument.

[0106] Test results:

[0107] Table 2

[0108]

[0109] Results analysis:

[0110] As can be seen from Comparative Examples 1-3, when the composition of the cover adhesive (rubber and hydroxyl-containing epoxy resin) changes, the resulting aramid core solid flame-retardant conveyor belt exhibits decreased bonding strength, increased wear, decreased tensile cold resistance coefficient, and decreased water contact angle. This indicates that the rubber and hydroxyl-containing epoxy resin in the cover adhesive of the present invention are indispensable, and specific rubber and hydroxyl-containing epoxy resin are required to achieve higher bonding strength, lower wear, larger tensile cold resistance coefficient, and higher water contact angle.

[0111] As can be seen from Comparative Examples 4-6, the composition of the modified filler in the cover adhesive changes, resulting in a decrease in the bonding strength, an increase in wear, a decrease in the tensile cold resistance coefficient, and a decrease in the water contact angle of the obtained aramid core solid flame-retardant conveyor belt. This indicates that only by using fluorosiloxane and diisocyanate to modify both silica and light calcium carbonate simultaneously, and by using rose-cluster-shaped and rice-grain-shaped light calcium carbonate, can the present invention achieve higher bonding strength, lower wear, a larger tensile cold resistance coefficient, and a higher water contact angle.

[0112] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention do not depart from the essence and scope of the technical solution of the present invention.

Claims

1. An aramid core solid flame-retardant conveyor belt, characterized in that, Includes cover adhesive, single-layer aramid fiber cloth, and adhesive backing; The covering adhesive, by weight, comprises the following raw materials: 90-110 parts rubber, 4-6 parts hydroxyl-containing epoxy resin, 35-45 parts modified filler, 10-20 parts flame retardant, 4-6 parts zinc oxide, 1-5 parts antioxidant, 1-5 parts accelerator, 1-3 parts sulfur, and 1-3 parts stearic acid. The rubbers include styrene-butadiene rubber, neodymium-based cis-butadiene rubber, natural rubber, and fluororubber; The fluororubber is a fluororubber composed of a copolymer of vinylidene fluoride, tetrafluoroethylene and perfluoroalkyl vinyl ether; The raw materials for the modified filler include light calcium carbonate, fumed silica, fluorosiloxanes, and diisocyanates. The light calcium carbonate comprises rose-shaped light calcium carbonate and rice-grain-shaped light calcium carbonate in a mass ratio of 4-8:3-5.

2. The aramid core solid flame-retardant conveyor belt according to claim 1, characterized in that, The mass ratio of the light calcium carbonate, fumed silica, fluorinated siloxane and diisocyanate is 20-30:5-20:0.5-2:2-5.

3. The aramid core solid flame-retardant conveyor belt according to claim 2, characterized in that, The method for preparing the modified filler includes the following steps: dispersing light calcium carbonate, fumed silica and fluorinated siloxane in an aqueous ethanol solution, performing a first ultrasonic reaction, and then filtering, washing and drying the mixture to obtain an intermediate product; dispersing the intermediate product and diisocyanate in an organic solvent, performing a second ultrasonic reaction, and then filtering, washing and drying the mixture to obtain the modified filler.

4. The aramid core solid flame-retardant conveyor belt according to claim 3, characterized in that, The flame retardant is selected from at least one of zinc borate, magnesium hydroxide, aluminum hydroxide, ammonium polyphosphate, and red phosphorus.

5. The aramid core solid flame-retardant conveyor belt according to claim 4, characterized in that, The adhesive, by weight, comprises the following raw materials: 40-65 parts chloroprene rubber, 15-25 parts natural rubber, 10-20 parts styrene-butadiene rubber, 10-15 parts bio-based itaconic acid ester rubber, 10-15 parts adhesive, 8-12 parts silica, 2-4 parts zinc oxide, 1-3 parts antioxidant, 1-3 parts accelerator, and 1-3 parts sulfur.

6. The aramid core solid flame-retardant conveyor belt according to claim 1, characterized in that, The aramid core solid flame-retardant conveyor belt consists of, from top to bottom, a cover rubber, a backing rubber, a single layer of aramid fiber cloth, a backing rubber, and a cover rubber; the thickness ratio of the cover rubber, the backing rubber, the single layer of aramid fiber cloth, the backing rubber, and the cover rubber is 10-15:1:2-4:1:4-6.

7. The method for preparing the aramid core solid flame-retardant conveyor belt according to any one of claims 1-6, characterized in that, Includes the following steps: (1) Preparation of cover rubber: Rubber is first mixed, hydroxyl epoxy resin, modified filler, flame retardant, zinc oxide, antioxidant and stearic acid are added for second mixing, accelerator and sulfur are added for third mixing, and calendering is performed after the third mixing to obtain cover rubber. (2) Preparation of adhesive: Chloroprene rubber, natural rubber, styrene-butadiene rubber and bio-based itaconic acid ester rubber are first mixed, then adhesive, silica, zinc oxide and antioxidant are added for second mixing, then sulfur and accelerator are added for third mixing, and after the third mixing is completed, calendering is performed to obtain adhesive. (3) After stacking the layers in the following order from top to bottom—cover rubber, adhesive, single-layer aramid fiber cloth, adhesive and cover rubber—vulcanization is performed to obtain the aramid core solid flame retardant conveyor belt.

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