Aramid fiber core whole-core flame-retardant conveying belt and preparation method thereof

Abstract

The invention belongs to the technical field of flame-retardant conveying belts, and particularly relates to an aramid fiber core whole-core flame-retardant conveying belt and a preparation method thereof. The whole aramid fiber core flame-retardant conveying belt comprises covering rubber, single-layer aramid fiber cloth and sticking rubber. The covering rubber is prepared from the following raw materials in parts by mass: 90 to 110 parts of rubber, 4 to 6 parts of hydroxyl-containing epoxy resin, 35 to 45 parts of modified filler, 10 to 20 parts of flame retardant, 4 to 6 parts of zinc oxide, 1 to 5 parts of anti-aging agent, 1 to 5 parts of accelerant, 1 to 3 parts of sulfur and 1 to 3 parts of stearic acid; the rubber comprises butadiene styrene rubber, neodymium butadiene rubber, natural rubber and fluororubber. The whole aramid fiber core flame-retardant conveying belt provided by the invention has excellent cold resistance, wear resistance, flame retardance, hydrophobicity and bonding strength.

Description

Technical Field

[0001] The invention belongs to the technical field of flame-retardant conveyor belts, and in particular relates to an aramid core whole-core flame-retardant conveyor belt and a preparation method thereof. Background Art

[0002] Material transportation is one of the important links in the development of various industries, and conveyor belts are an important part of material transportation. In coal mining and chemical industries, since materials are flammable and explosive, conveyor belts are required to have good flame retardant properties to prevent fire accidents.

[0003] At present, the conveyor belts used in coal mines are mainly fabric flame retardant conveyor belts and steel cord flame retardant conveyor belts. Fabric flame retardant conveyor belts are lighter than steel cord flame retardant conveyor belts and are widely used. The braided materials used as the core of the traditional fabric flame retardant conveyor belt are mainly nylon, polyester and cotton fibers. However, the strength of the above braided materials is low. In order to have good strength, a multi-layer braided structure is required, which makes it difficult to impregnate the slurry, resulting in an impact on the performance of the conveyor belt, thus limiting its application.

[0004] Aramid has the advantages of high strength, high modulus, light weight, flame retardancy and high temperature resistance. It is an ideal skeleton material for high-performance conveyor belts. Traditional aramid core flame retardant conveyor belts usually consist of a cover layer, an aramid core and an impregnated rubber / adhesive layer. For example, the authorization publication number is CN 107216560 B's Chinese patent discloses an aramid fabric integral core flame retardant belt and a manufacturing method thereof, the conveyor belt includes a covering layer, an aramid integral belt core and a belt core impregnated rubber compound: the covering layer adopts PVC / CM / TPU blended thermoplastic elastomer, which has good flame retardancy, high tensile strength, excellent elasticity, good wear resistance, and high bonding strength with the integral belt core after dipping and plasticization; the fabric integral belt core has a three-layer structure, and the radial force line adopts aramid fiber, which has high strength, thin belt body, and light weight, which can greatly reduce the energy consumption during the operation of the conveyor belt; the belt core impregnated rubber compound contains MDI thickener, which greatly improves the bonding strength between the plasticized integral belt core and the covering layer, ensuring that the conveyor belt does not delaminate during long-term operation. This scheme adopts vacuum impregnation integral belt core, extruder veneer molding, and dynamic vulcanization process to produce conveyor belts, which has simple process, low energy consumption and high production efficiency. However, the covering layer and belt core impregnated rubber compound in this technical scheme are mainly composed of polyvinyl chloride resin, and the poor cold resistance of polyvinyl chloride resin limits its use in cold environments.

[0005] A Chinese patent with publication number CN 117681515 A discloses an environmentally friendly aramid rope flame-retardant conveyor belt and a preparation method thereof. The environmentally friendly aramid rope flame-retardant conveyor belt comprises, from top to bottom, a covering rubber, a core layer rubber, an aramid rope, a core layer rubber and a covering rubber, wherein the covering rubber comprises chloroprene rubber, modified chlorosulfonated polyethylene rubber, carbon black, activated glass fiber powder, decabromodiphenyl ether, zinc oxide, zinc borate, magnesium oxide, stearic acid, an antioxidant, an accelerator and sulfur; the core layer rubber comprises chloroprene rubber, natural rubber, molybdenum-based high vinyl polybutadiene rubber, zinc oxide, stearic acid, sulfur, adhesive, accelerator, antioxidant and coumarone. This technical solution ensures the strength and elongation properties, wear resistance and impact resistance, flame retardancy and antistatic properties of the rubber and the coordination of the various components of the core body through the matching and synergy of various systems, thereby producing an environmentally friendly aramid rope flame-retardant conveyor belt with excellent comprehensive performance; however, the wear amount in this technical solution is 140mm 3 The wear amount is large and no attention is paid to cold resistance. Summary of the invention

[0006] The purpose of the present invention is to overcome the problem that the cold resistance and wear resistance of the aramid core whole-core flame-retardant conveyor belt in the prior art need to be improved, and to provide an aramid core whole-core flame-retardant conveyor belt. The covering rubber adopts the combined effect of styrene-butadiene rubber, neodymium-based butadiene rubber, natural rubber and fluororubber, and the light calcium carbonate and white carbon black are modified by fluorinated silicone and diisocyanate. The obtained aramid core whole-core 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 flame-retardant conveyor belt.

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

[0009] The present invention provides an aramid core whole-core flame-retardant conveyor belt, comprising a covering rubber, a single-layer aramid fiber cloth and a pasting rubber;

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

[0011] The rubber includes styrene-butadiene rubber, neodymium-based butadiene rubber, natural rubber and fluororubber.

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

[0013] Furthermore, the content of cis-1,4-polybutadiene in the neodymium-based butadiene rubber is ≥96%.

[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 64-66wt%.

[0016] Furthermore, the raw materials of the modified filler include light calcium carbonate, white carbon black, fluorinated silicone and diisocyanate.

[0017] Furthermore, the fluorine-containing silicone contains 13 fluorine atoms.

[0018] Furthermore, the fluorine-containing siloxane is tridecafluorooctyltriethoxysilane.

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

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

[0021] Furthermore, the mass ratio of the light calcium carbonate, white carbon black, 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 includes rose-cluster-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 comprises the following steps: dispersing light calcium carbonate, white carbon black and fluorinated silicone in an ethanol aqueous solution, conducting a first ultrasonic reaction, and filtering, washing and drying in sequence after the reaction to obtain an intermediate product; dispersing the intermediate product and diisocyanate in an organic solvent, conducting a second ultrasonic reaction, and filtering, washing and drying in sequence after the reaction to obtain a modified filler.

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

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

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

[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 the magnesium hydroxide to the aluminum hydroxide is 1-3:1-3, preferably 1:1.

[0034] Furthermore, the raw materials of the adhesive patch include, by mass: 40-65 parts of chloroprene rubber, 15-25 parts of natural rubber, 10-20 parts of styrene-butadiene rubber, 10-15 parts of bio-based itaconate rubber, 10-15 parts of adhesive, 8-12 parts of white carbon black, 2-4 parts of zinc oxide, 1-3 parts of antioxidant, 1-3 parts of accelerator, and 1-3 parts of 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 bisthiocarbonyl disulfide and N-cyclohexyl-2-benzothiazole sulfenamide.

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

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

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

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

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

[0042] (1) Preparing a covering rubber: kneading the rubber for the first time, adding a hydroxyl-containing epoxy resin, a modified filler, a flame retardant, zinc oxide, an antioxidant and stearic acid for the second time, adding an accelerator and sulfur for the third time, and calendering after the third time to obtain the covering rubber;

[0043] (2) Preparing a rubber coating: mixing chloroprene rubber, natural rubber, styrene-butadiene rubber and bio-based itaconate rubber for a first time, adding an adhesive, white carbon black, zinc oxide and an antioxidant for a second time, adding sulfur and an accelerator for a third time, and calendering after the third time mixing to obtain a rubber coating;

[0044] (3) The aramid core flame-retardant conveyor belt is obtained by stacking the covering rubber, pasting rubber, single-layer aramid fiber cloth, pasting rubber and covering rubber in order from top to bottom and then vulcanizing them.

[0045] Furthermore, in the preparation process of the covering rubber and the sticker, the first mixing temperature is 100-110°C, and the mixing time is 1-3 minutes; the second mixing temperature is 95-105°C, and the mixing time is 3-5 minutes; the third mixing temperature is 70-80°C, and the mixing time is 2-5 minutes.

[0046] Furthermore, the calendering temperature during the preparation process of the covering adhesive and the pasting adhesive is 90-100°C.

[0047] Furthermore, the vulcanization temperature is 145-155° C., 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 the present invention, the rubber in the covering rubber includes styrene-butadiene rubber, neodymium-based cis-1,4-butadiene rubber, natural rubber and fluororubber, which are combined with flame retardants to form a high-density cross-linked network after vulcanization. The obtained aramid core flame-retardant conveyor belt has not only excellent flame retardancy and wear resistance, but also excellent flexibility at low temperatures. In particular, the combination of specific neodymium-based cis-1,4-butadiene rubber and specific fluororubber makes the aramid core flame-retardant conveyor belt still have a high tensile cold resistance coefficient at -50°C; at the same time, the styrene-butadiene rubber, neodymium-based cis-1,4-butadiene rubber, natural rubber and fluororubber in the covering rubber of the present invention work together with the bio-based itaconate rubber in the coating rubber, so that the covering rubber and the single-layer aramid fiber cloth have excellent bonding strength.

[0050] 2. The surface of coal just after mining contains a certain amount of moisture, which is easy to freeze and adhere to the surface of the conveyor belt under cold conditions. A conveyor belt with good hydrophobicity can avoid this phenomenon to a certain extent. Although the fluororubber in the covering rubber of the present invention makes the aramid core flame retardant conveyor belt have good cold resistance and certain hydrophobicity, the hydrophobic effect is poor. Based on this, the present invention creatively uses fluorinated silicone and diisocyanate to modify light calcium carbonate and white carbon black, and can obtain an aramid core flame retardant conveyor belt with excellent hydrophobicity. The modified light Calcium carbonate and white carbon black contain fluorine groups and isocyanate groups on their surfaces. During the preparation of the covering rubber, the fluorine-containing groups are enriched on the surface of the covering rubber and work together with a specific fluorine-containing resin to form a continuous fluorinated layer to improve the hydrophobicity. The isocyanate groups and hydroxyl-containing epoxy resins are cross-linked to allow light calcium carbonate and white carbon black to exist stably in the system. The inventors also unexpectedly discovered that the use of rose-cluster-shaped light calcium carbonate and rice-grain-shaped light calcium carbonate can further reduce the wear of the aramid core flame-retardant conveyor belt and improve the tensile cold resistance coefficient of the aramid core flame-retardant conveyor belt. DETAILED DESCRIPTION

[0051] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, a specific implementation scheme is now described in detail.

[0052] The present invention is further described below in conjunction with the 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 the different requirements of specific use, and the implementation conditions not indicated are conventional conditions in the industry. The technical features involved in each embodiment of the present invention can be combined with each other as long as they do not conflict with each other.

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

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

[0055] Table 1

[0056]

[0057] Embodiment 1 An aramid core flame retardant conveyor belt, which comprises, from top to bottom, a covering rubber, a pasting rubber, a single layer of aramid fiber cloth, a pasting rubber and a covering rubber;

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

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

[0060] The raw materials of the modified filler are composed of light calcium carbonate, white carbon black, tridecafluorooctyl triethoxysilane and toluene diisocyanate in a mass ratio of 20:10:1.8:3.

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

[0062] The preparation method of the modified filler is as follows: light calcium carbonate, white carbon black and fluorinated silicone are dispersed in an ethanol aqueous solution, subjected to a first ultrasonic reaction, and then filtered, washed and dried in sequence to obtain an intermediate product; the intermediate product and diisocyanate are dispersed in dimethylformamide, subjected to a second ultrasonic reaction, and then filtered, washed and dried in sequence to obtain the modified filler.

[0063] The ratio of the total mass of the ethanol aqueous solution to the light calcium carbonate and white carbon black 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 h.

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

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

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

[0070] The adhesive tape is composed of 45 parts of chloroprene rubber, 20 parts of natural rubber, 20 parts of styrene-butadiene rubber, 15 parts of bio-based itaconate rubber, 10 parts of adhesive ADA, 8 parts of white carbon black, 2 parts of zinc oxide, 1 part of antioxidant, 1 part of accelerator, and 1 part of sulfur, by weight.

[0071] The accelerator in the covering rubber and the adhesive bonding rubber is dibenzothiazole disulfide.

[0072] The antioxidant in the covering adhesive and the pasting adhesive is 2,6-di-tert-butyl-p-cresol.

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

[0074] The method for preparing the above-mentioned aramid core flame-retardant conveyor belt comprises the following steps:

[0075] (1) Preparing the covering rubber: the rubber is first kneaded at 100°C for 2 minutes, a hydroxyl-containing epoxy resin, a modified filler, a flame retardant, zinc oxide, an antioxidant and stearic acid are added, and the rubber is second kneaded at 95°C for 4 minutes, an accelerator and sulfur are added, and the rubber is thirdly kneaded at 80°C for 3 minutes, and after the third kneading, the rubber is calendered at 100°C to obtain the covering rubber;

[0076] (2) Preparing a rubber patch: mixing chloroprene rubber, natural rubber, styrene-butadiene rubber and bio-based itaconate rubber for a first time at 100° C. for 2 minutes, adding an adhesive, white carbon black, zinc oxide and an antioxidant for a second time at 100° C. for 3 minutes, adding sulfur and an accelerator for a third time at 80° C. for 2 minutes, and after the third time mixing, rolling at 100° C. to obtain a rubber patch;

[0077] (3) The aramid core flame-retardant conveyor belt is obtained by stacking the covering rubber, pasting rubber, single-layer aramid fiber cloth, pasting rubber and covering rubber in order from top to bottom and vulcanizing them at 150°C for 30 minutes.

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

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

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

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

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

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

[0084] Comparative Example 1 A flame-retardant conveyor belt with an aramid core

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

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

[0087] Comparative Example 2 A flame-retardant conveyor belt with an aramid core

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

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

[0090] Comparative Example 3 A flame-retardant conveyor belt with an aramid core

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

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

[0093] Comparative Example 4 A flame-retardant conveyor belt with an aramid core

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

[0095] The preparation method of the modified filler is as follows: light calcium carbonate, white carbon black and fluorinated silicone are dispersed in an ethanol aqueous solution, subjected to a first ultrasonic reaction, and then filtered, washed and dried in sequence to obtain the modified filler.

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

[0097] Comparative Example 5 A flame-retardant conveyor belt with an aramid core

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

[0099] The preparation method of the modified filler is as follows: light calcium carbonate, white carbon black and diisocyanate are dispersed in dimethylformamide, and ultrasonic reaction is performed for the second time, and after the reaction is completed, filtering, washing and drying are performed in sequence to obtain the modified filler.

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

[0101] Comparative Example 6

[0102] The specific implementation method is the same as that of 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 fully flame-retardant conveyor belt is the same as that of Example 2.

[0104] Test Example

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

[0106] Test Results:

[0107] Table 2

[0108]

[0109] Result Analysis:

[0110] It can be seen from Comparative Examples 1-3 that when the composition in the cover rubber (rubber and hydroxyl-containing epoxy resin) changes, the adhesion strength of the obtained aramid core fully flame-retardant conveyor belt decreases, the abrasion amount increases, the tensile cold resistance coefficient decreases, and the water contact angle decreases, indicating that both the rubber and the hydroxyl-containing epoxy resin in the cover rubber of the present invention are indispensable, and specific rubber and hydroxyl-containing epoxy resin are required to achieve higher adhesion strength, lower abrasion amount, larger tensile cold resistance coefficient and higher water contact angle;

[0111] It can be seen from Comparative Examples 4-6 that when the composition of the modified filler in the cover rubber changes, the adhesion strength of the obtained aramid core fully flame-retardant conveyor belt decreases, the abrasion amount increases, the tensile cold resistance coefficient decreases, and the water contact angle decreases, indicating that only by using fluorosiloxane and diisocyanate to modify silica and light calcium carbonate at the same time, and using rose-clustered light calcium carbonate and rice-grained light calcium carbonate in the present invention can higher adhesion strength, lower abrasion amount, larger tensile cold resistance coefficient and higher water contact angle be achieved.

[0112] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, rather than a limitation on the protection scope of the present invention. Any simple modification or equivalent replacement of the technical solution of the present invention by those of ordinary skill in the art shall not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A flame-retardant conveyor belt with an aramid core, characterized in that: Including covering rubber, single-layer aramid fiber cloth and adhesive tape; The covering rubber comprises, by weight, 90-110 parts of rubber, 4-6 parts of hydroxyl-containing epoxy resin, 35-45 parts of modified filler, 10-20 parts of flame retardant, 4-6 parts of zinc oxide, 1-5 parts of antioxidant, 1-5 parts of accelerator, 1-3 parts of sulfur, and 1-3 parts of stearic acid; The rubber includes styrene-butadiene rubber, neodymium-based butadiene rubber, natural rubber and fluororubber.

2. The aramid core flame-retardant conveyor belt according to claim 1, characterized in that: The fluororubber is a fluororubber composed of a copolymer of vinylidene fluoride, tetrafluoroethylene and perfluoroalkyl vinyl ether.

3. The aramid core flame-retardant conveyor belt according to claim 2, characterized in that: The raw materials of the modified filler include light calcium carbonate, white carbon black, fluorine-containing silicone and diisocyanate.

4. The aramid core flame-retardant conveyor belt according to claim 3, characterized in that: The mass ratio of the light calcium carbonate, white carbon black, perfluoroalkylsiloxane and diisocyanate is 20-30:5-20:0.5-2:2-5.

5. The aramid core flame-retardant conveyor belt according to claim 4, characterized in that: 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.

6. The aramid core flame-retardant conveyor belt according to claim 5, characterized in that: The preparation method of the modified filler comprises the following steps: dispersing light calcium carbonate, white carbon black and fluorinated silicone in an ethanol aqueous solution, performing a first ultrasonic reaction, filtering, washing and drying in sequence after the reaction is completed to obtain an intermediate product; dispersing the intermediate product and diisocyanate in an organic solvent, performing a second ultrasonic reaction, filtering, washing and drying in sequence after the reaction is completed to obtain the modified filler.

7. The aramid core flame-retardant conveyor belt according to claim 6, characterized in that: The flame retardant is selected from at least one of zinc borate, magnesium hydroxide, aluminum hydroxide, ammonium polyphosphate and red phosphorus.

8. The aramid core flame-retardant conveyor belt according to claim 7, characterized in that: The adhesive patch comprises, by weight, 40-65 parts of chloroprene rubber, 15-25 parts of natural rubber, 10-20 parts of styrene-butadiene rubber, 10-15 parts of bio-based itaconate rubber, 10-15 parts of adhesive, 8-12 parts of white carbon black, 2-4 parts of zinc oxide, 1-3 parts of antioxidant, 1-3 parts of accelerator, and 1-3 parts of sulfur.

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

10. The method for preparing the aramid core flame-retardant conveyor belt according to any one of claims 1 to 9, characterized in that: The following steps are involved: (1) Preparing a covering rubber: kneading the rubber for the first time, adding a hydroxyl-containing epoxy resin, a modified filler, a flame retardant, zinc oxide, an antioxidant and stearic acid for the second time, adding an accelerator and sulfur for the third time, and calendering after the third time to obtain the covering rubber; (2) Preparing a rubber coating: mixing chloroprene rubber, natural rubber, styrene-butadiene rubber and bio-based itaconate rubber for a first time, adding an adhesive, white carbon black, zinc oxide and an antioxidant for a second time, adding sulfur and an accelerator for a third time, and calendering after the third time mixing to obtain a rubber coating; (3) The aramid core flame-retardant conveyor belt is obtained by stacking the covering rubber, pasting rubber, single-layer aramid fiber cloth, pasting rubber and covering rubber in order from top to bottom and then vulcanizing them.

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