High-strength wear-resistant flame-retardant conveying belt and preparation method thereof

Abstract

The invention relates to the technical field of conveying belts, in particular to a high-strength wear-resistant flame-retardant conveying belt and a preparation method thereof. The preparation method comprises the following steps: adding the modified polyvinyl chloride, the chloroprene rubber, the modified hydrotalcite flame retardant, the lauryl sodium sulfate, the zinc stearate and the N-phenyl-beta-naphthylamine into a stirrer, and uniformly stirring and mixing to obtain a mixture; and conveying the mixture into an extruder, uniformly coating two surfaces of polyester fiber cloth with the melt-extruded material liquid, and carrying out hot-pressing cooling to obtain the high-strength wear-resistant flame-retardant conveying belt. The conveyor belt prepared by the invention not only has good flame retardant property, but also has excellent mechanical strength and wear resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of rubber conveyor belt materials, and particularly to a high-strength wear-resistant flame-retardant conveyor belt and a preparation method thereof. Background Art

[0002] In many industrial fields today, as a key component for material transportation, conveyor belts have a wide range of complex application scenarios. Polyvinyl chloride (PVC) conveyor belts have been applied in many industries due to their relatively low cost, good chemical stability, and certain mechanical properties. However, with the continuous improvement of safety production standards and the emergence of various complex working conditions, the key problem of poor flame retardancy of PVC conveyor belts has become increasingly prominent, seriously restricting their further promotion and safe use in some fields with high fire prevention requirements.

[0003] Although traditional PVC conveyor belts have certain initial flame retardancy due to the presence of chlorine atoms in their molecular structure, this flame retardancy has obvious limitations in practical applications. For example, during the coal transportation process in underground coal mines, due to the presence of flammable and explosive gases such as gas, once a fire breaks out on the conveyor belt, even a tiny fire source may trigger a serious explosion accident, endangering the lives of personnel and the safety of the mine. Existing PVC conveyor belts cannot effectively prevent the rapid spread of fire in such a high-risk environment. Although the hydrogen chloride gas released can, to a certain extent, inhibit the combustion reaction, it is far from sufficient to meet the complex and harsh fire prevention requirements underground.

[0004] In the petrochemical industry, when PVC conveyor belts are used to transport various chemical raw materials and products, they also face severe flame retardancy tests. In the chemical production environment, there are often flammable, explosive, and volatile substances. Once a fire breaks out, traditional PVC conveyor belts not only cannot prevent the spread of the fire but also, due to the possible generation of toxic and harmful gases during their combustion process, will further exacerbate the severity of the accident, posing a serious threat to the lives and health of on-site operators and potentially causing huge economic losses and environmental pollution.

[0005] In addition, in some warehousing and logistics sites, especially warehouses storing flammable items, the insufficient flame retardancy of PVC conveyor belts has also become a potential safety hazard. When a fire source is generated on the conveyor belt due to friction, electrical failure, or other reasons, due to its poor flame retardancy, the fire is likely to get out of control quickly, causing devastating damage to the entire warehousing facility and goods, and also bringing unpredictable risks to the surrounding environment.

[0006] In summary, the defects of existing PVC conveyor belts in terms of flame retardancy can no longer meet the strict requirements of modern industrial production for fire safety. Therefore, there is an urgent need to develop an innovative technology that can significantly improve the flame retardancy of polyvinyl chloride conveyor belts to fill this technological gap, expand the application scope of PVC conveyor belts, ensure the safety and stability of production operations in various industries, reduce the risk and losses of fire accidents, which is of crucial significance and broad market prospects for promoting the safe development of the industrial field. Summary of the Invention

[0007] In order to overcome the above prior art problems, the present invention provides a high-strength wear-resistant flame-retardant conveyor belt and its preparation method. The conveyor belt prepared by the present invention not only has good flame retardancy but also excellent mechanical strength and wear resistance.

[0008] In order to achieve the above invention purposes, the present invention adopts the following technical solutions: A high-strength wear-resistant flame-retardant conveyor belt, comprising conveyor belt rubber material and a polyester fiber cloth located inside the conveyor belt rubber material. The conveyor belt rubber material comprises the following components by weight parts: 120 - 160 parts of modified polyvinyl chloride, 20 - 30 parts of chloroprene rubber, 3 - 7 parts of modified hydrotalcite flame retardant, 1 - 3 parts of sodium dodecyl sulfate, 1 - 3 parts of zinc stearate, 1 - 3 parts of N-phenyl-β-naphthylamine.

[0009] The present invention uses polyvinyl chloride and chloroprene rubber as the main components of the conveyor belt; hydrotalcite as the flame retardant of the conveyor belt. Hydrotalcite-based materials are a very effective inorganic flame retardant. During the combustion of the conveyor belt, it can form a dense protective film on the surface of the material, which can prevent the transfer of heat and oxygen to the internal material and play a role in isolating the flame; sodium dodecyl sulfate mainly plays a dispersing role, which can help disperse various additives evenly in the matrix of polyvinyl chloride and chloroprene rubber; during the processing and use of polyvinyl chloride, due to the influence of factors such as heat, PVC may undergo a degradation reaction. Zinc stearate can play a role in thermal stability. It can absorb the hydrogen chloride gas generated during the degradation of PVC and inhibit the further degradation of PVC, which helps to maintain the performance of polyvinyl chloride and prevent it from becoming brittle and discolored due to thermal degradation during processing and use; N-phenyl-β-naphthylamine is used as an antioxidant. During the use of the conveyor belt, the rubber and plastic components will inevitably be oxidized by factors such as oxygen, heat, and light. This antioxidant can capture the free radicals generated during the oxidation process of the material and prevent the progress of the oxidation chain reaction, thereby effectively delaying the aging process of the conveyor belt and maintaining its physical properties and appearance.

[0010] Preferably, the preparation of the modified hydrotalcite flame retardant comprises the following steps: 1) Add hydrotalcite to deionized water and disperse it evenly by ultrasonic oscillation to obtain a hydrotalcite suspension; 2) Add 3-sulfopropyl glycidyl ether to water and stir to dissolve it to obtain a 3-sulfopropyl glycidyl ether solution; 3) Drop the 3-sulfopropyl glycidyl ether solution into the hydrotalcite suspension, heat and stir to react, and after centrifugal separation, washing and drying, obtain 3-sulfopropyl glycidyl ether intercalated hydrotalcite; 4) Add carboxymethyl chitosan to deionized water and stir to dissolve it to obtain a carboxymethyl chitosan aqueous solution. Add 3-sulfopropyl glycidyl ether intercalated hydrotalcite to the carboxymethyl chitosan aqueous solution, heat and stir to react, and after centrifugal separation, washing and drying, obtain a modified hydrotalcite flame retardant.

[0011] In the technical solution of the present invention, by adding a hydrotalcite flame retardant during the transportation of polyvinyl chloride, the flame retardant performance of the conveyor belt is improved. However, the hydrotalcite flame retardant is prone to agglomeration and uneven dispersion in the conveyor belt, which affects the improvement of the flame retardant performance of the conveyor belt by the hydrotalcite flame retardant. The present invention adopts a modification treatment method of intercalating 3-sulfopropyl glycidyl ether into the hydrotalcite layer, effectively increasing the layer spacing of the hydrotalcite and making its surface organic, avoiding the occurrence of agglomeration of the hydrotalcite flame retardant. This modification enables the hydrotalcite flame retardant to be evenly dispersed in the polyvinyl chloride conveyor belt matrix, giving full play to its flame retardant effect and forming a stable and efficient flame retardant system. In the face of an external fire source, the modified hydrotalcite flame retardant and the polyvinyl chloride conveyor belt act synergistically, significantly improving the overall flame retardant performance of the conveyor belt, effectively reducing the risk of fire, and enabling it to be better applied to industrial transportation scenarios with strict fire prevention requirements such as coal mines and petrochemical industries.

[0012] Preferably, in step 3), the mass ratio of hydrotalcite to 3-sulfopropyl glycidyl ether is 1:0.3 - 0.8.

[0013] Preferably, in step 4), the mass ratio of 3-sulfopropyl glycidyl ether intercalated hydrotalcite to carboxymethyl chitosan is 1:0.5 - 1.

[0014] Preferably, in step 4), the heating reaction temperature is 70 - 80 °C and the stirring reaction time is 2 - 4 h.

[0015] Preferably, the preparation method of the modified polyvinyl chloride includes the following steps: a) Add polyvinyl chloride powder to an oven for drying to remove moisture and volatile impurities, and set aside; b) Add hydroxyethyl acrylate to toluene, stir to dissolve it, and then add a benzoyl peroxide initiator and stir evenly to obtain a mixed solution; c) Add the dried polyvinyl chloride powder into the above mixed solution, heat and stir for reaction, and after cooling to room temperature, add sodium hydroxide solution to neutralize acidic substances and precipitate the product; d) Through suction filtration separation, washing and drying, modified polyvinyl chloride is obtained.

[0016] After adding hydrotalcite flame retardant to the polyvinyl chloride conveyor belt, the research team of the present invention found that the hydrotalcite flame retardant has a negative impact on the mechanical strength of polyvinyl chloride. This may be due to problems such as poor compatibility and weak binding force between hydrotalcite and the polyvinyl chloride matrix, resulting in a decrease in the mechanical strength of the conveyor belt. The present invention further carried out in-depth improvement measures for this problem: First, carboxymethyl chitosan was grafted onto the intercalated modified hydrotalcite (the amino group on carboxymethyl chitosan undergoes a ring-opening reaction with the epoxy group of 3-sulfopropyl glycidyl ether between the hydrotalcite layers), so that the surface of the hydrotalcite is loaded with more hydroxyl groups. At the same time, 2-hydroxyethyl acrylate undergoes a grafting reaction with polyvinyl chloride under the action of benzoyl peroxide initiator, so that polyvinyl chloride is also loaded with hydroxyl groups. These two structures with hydroxyl groups attract each other through hydrogen bond forces, greatly enhancing the binding force between the hydrotalcite flame retardant and the polyvinyl chloride conveyor belt. This strong binding effect makes the hydrotalcite flame retardant no longer a simple physical filling in the conveyor belt, but forms a tight chemical and physical binding network with the matrix. When subjected to external forces, it can effectively transfer stress and avoid stress concentration caused by the separation of the filler and the matrix. Therefore, the mechanical performance indicators of the polyvinyl chloride conveyor belt treated by the present invention have been effectively improved, ensuring the stability and reliability of the conveyor belt during the long-distance and high-intensity transportation of materials, extending the service life of the conveyor belt, and reducing the operating costs brought about by frequent replacement of the conveyor belt due to insufficient mechanical properties. In addition, in the present invention, by grafting 2-hydroxyethyl acrylate onto polyvinyl chloride and enhancing the binding effect between the hydrotalcite flame retardant and polyvinyl chloride, the wear resistance of the conveyor belt is indirectly positively affected, while improving the wear resistance of the conveyor belt. At the same time, the tight binding effect between the hydrotalcite flame retardant and polyvinyl chloride avoids the situation of filler shedding during friction due to the weak binding between the two, ensuring the integrity of the conveyor belt structure and further improving the overall wear resistance.

[0017] Preferably, in the step b), the addition amount of benzoyl peroxide is 0.5 - 3.0 wt% of 2-hydroxyethyl acrylate.

[0018] Preferably, in the step c), the mass ratio of polyvinyl chloride to 2-hydroxyethyl acrylate is 1:0.5 - 0.8.

[0019] Preferably, in the step c), the heating reaction temperature is 80 - 85 °C, and the reaction time is 3 - 5 h.

[0020] A preparation method of a high-strength wear-resistant and flame-retardant conveyor belt, comprising the following steps: Put modified polyvinyl chloride, chloroprene rubber, modified hydrotalcite flame retardant, sodium dodecyl sulfate, zinc stearate, and N-phenyl-β-naphthylamine into a blender and stir and mix evenly to obtain a mixture. Transport the mixture to an extruder, evenly coat the molten extruded liquid on both sides of the polyester fiber cloth, and after hot pressing and cooling, obtain a high-strength wear-resistant and flame-retardant conveyor belt.

[0021] The present invention has the following beneficial effects: 1) Hydrotalcite is used as the flame retardant of the conveyor belt. Hydrotalcite materials are a very effective inorganic flame retardant. During the combustion of the conveyor belt, it can form a dense protective film on the surface of the material. This film can prevent the transfer of heat and oxygen to the internal material, play a role in isolating the flame, and improve the flame retardant performance of the conveyor belt; 2) The present invention adopts a modification treatment method of intercalating 3-sulfopropyl glycidyl ether into the interlayer of hydrotalcite, effectively increasing the interlayer spacing of hydrotalcite and making its surface organic, avoiding the agglomeration of the hydrotalcite flame retardant. This modification enables the hydrotalcite flame retardant to be evenly dispersed in the polyvinyl chloride conveyor belt matrix, fully exert its flame retardant effect, and form a stable and efficient flame retardant system; 3) Further modification of hydrotalcite and polyvinyl chloride solves the problem that the hydrotalcite flame retardant causes a decrease in the mechanical strength of polyvinyl chloride. Specific embodiments

[0022] The following further clearly and detailedly describes the present invention in combination with specific embodiments. Those of ordinary skill in the art will be able to implement the present invention based on these descriptions. In addition, the embodiments of the present invention involved in the following description are usually only a part of the embodiments of the present invention, rather than all the embodiments. Therefore, all other embodiments obtained by those of ordinary skill in the art without creative efforts based on the embodiments of the present invention shall fall within the scope of protection of the present invention.

[0023] Unless otherwise specified, the raw materials used in the embodiments of the present invention are all commercially available or raw materials that can be obtained by those skilled in the art; unless otherwise specified, the methods used in the embodiments of the present invention are all methods mastered by those skilled in the art.

[0024] Example 1: A high-strength wear-resistant and flame-retardant conveyor belt, comprising a conveyor belt rubber material and a polyester fiber cloth inside the conveyor belt rubber material. The conveyor belt rubber material comprises the following components by weight: 150 parts of modified polyvinyl chloride, 28 parts of chloroprene rubber, 6 parts of modified hydrotalcite flame retardant, 2 parts of sodium dodecyl sulfate, 2 parts of zinc stearate, and 2 parts of N-phenyl-β-naphthylamine.

[0025] The preparation method of the modified hydrotalcite flame retardant comprises the following steps: 1) Add 10 g of hydrotalcite into 200 mL of deionized water, disperse it evenly by ultrasonic oscillation to obtain a hydrotalcite suspension; 2) Add 7 g of 3-sulfopropyl glycidyl ether into 100 mL of deionized water, stir and dissolve it to obtain a 3-sulfopropyl glycidyl ether solution; 3) Drop the 3-sulfopropyl glycidyl ether solution into the hydrotalcite suspension, heat and stir the reaction at 45 °C for 3 h, and obtain 3-sulfopropyl glycidyl ether intercalated hydrotalcite after centrifugal separation, washing and drying; 4) Add 9 g of carboxymethyl chitosan into 200 mL of deionized water, stir and dissolve it to obtain a carboxymethyl chitosan aqueous solution. Add 10 g of 3-sulfopropyl glycidyl ether intercalated hydrotalcite into the carboxymethyl chitosan aqueous solution, heat to 75 °C, stir and react for 3.5 h, and obtain the modified hydrotalcite flame retardant after centrifugal separation, washing and drying.

[0026] The preparation method of the modified polyvinyl chloride comprises the following steps: a) Add the polyvinyl chloride powder into an oven, dry it at 60 °C for 4 h to remove moisture and volatile impurities, and set aside; b) Add 10 g of 2-hydroxyethyl acrylate into 150 mL of toluene, stir and dissolve it, then add benzoyl peroxide initiator, and the addition amount of benzoyl peroxide is 2.5 wt% of 2-hydroxyethyl acrylate, stir evenly to obtain a mixed solution; c) Add the dried polyvinyl chloride powder into the above mixed solution, and the mass ratio of the polyvinyl chloride powder to 2-hydroxyethyl acrylate is 1:0.7. Heat to 83 °C, stir and react for 4 h. After cooling to room temperature, add sodium hydroxide solution (100 mL of 10% sodium hydroxide solution) to neutralize acidic substances and precipitate the product; d) After suction filtration separation, washing and drying, obtain the modified polyvinyl chloride.

[0027] The preparation method of a high-strength wear-resistant flame-retardant conveyor belt comprises the following steps: Add the modified polyvinyl chloride, chloroprene rubber, modified hydrotalcite flame retardant, sodium dodecyl sulfate, zinc stearate, and N-phenyl-β-naphthylamine into a blender, stir and mix evenly to obtain a mixture; Convey the mixture to an extruder, evenly coat the molten extruded liquid on both sides of the polyester fiber cloth, control the surface glue thickness at 7 mm, and obtain the high-strength wear-resistant flame-retardant conveyor belt after hot pressing and cooling.

[0028] Example 2: A high-strength wear-resistant and flame-retardant conveyor belt, comprising a conveyor belt rubber material and a polyester fiber cloth inside the conveyor belt rubber material. The conveyor belt rubber material comprises the following components by weight: 130 parts of modified polyvinyl chloride, 22 parts of chloroprene rubber, 4 parts of modified hydrotalcite flame retardant, 2 parts of sodium dodecyl sulfate, 2 parts of zinc stearate, and 2 parts of N-phenyl-β-naphthylamine.

[0029] The preparation method of the modified hydrotalcite flame retardant comprises the following steps: 1) Add 10 g of hydrotalcite to 200 mL of deionized water, and disperse it evenly by ultrasonic oscillation to obtain a hydrotalcite suspension; 2) Add 4 g of 3-sulfopropyl glycidyl ether to 100 mL of deionized water and stir to dissolve it to obtain a 3-sulfopropyl glycidyl ether solution; 3) Drop the 3-sulfopropyl glycidyl ether solution into the hydrotalcite suspension, heat and stir the reaction at 45 °C for 3 h, and obtain 3-sulfopropyl glycidyl ether intercalated hydrotalcite through centrifugal separation, washing and drying; 4) Add 6 g of carboxymethyl chitosan to 200 mL of deionized water and stir to dissolve it to obtain a carboxymethyl chitosan aqueous solution. Add 10 g of 3-sulfopropyl glycidyl ether intercalated hydrotalcite to the carboxymethyl chitosan aqueous solution, heat to 75 °C, and stir the reaction for 2.5 h. Obtain the modified hydrotalcite flame retardant through centrifugal separation, washing and drying.

[0030] The preparation method of the modified polyvinyl chloride comprises the following steps: a) Add the polyvinyl chloride powder to an oven and dry it at 60 °C for 4 h to remove moisture and volatile impurities, and set aside; b) Add 10 g of 2-hydroxyethyl acrylate to 150 mL of toluene, stir to dissolve it, and then add a benzoyl peroxide initiator. The addition amount of benzoyl peroxide is 1.0 wt% of 2-hydroxyethyl acrylate, and stir evenly to obtain a mixed solution; c) Add the dried polyvinyl chloride powder to the above mixed solution. The mass ratio of the polyvinyl chloride powder to 2-hydroxyethyl acrylate is 1:0.6. Heat to 83 °C, stir the reaction for 4 h, and after cooling to room temperature, add a sodium hydroxide solution (100 mL of 10% sodium hydroxide solution) to neutralize acidic substances and precipitate the product; d) Obtain the modified polyvinyl chloride through suction filtration separation, washing and drying.

[0031] A preparation method of a high-strength wear-resistant and flame-retardant conveyor belt comprises the following steps: Add the modified polyvinyl chloride, chloroprene rubber, modified hydrotalcite flame retardant, sodium dodecyl sulfate, zinc stearate, and N-phenyl-β-naphthylamine into a mixer and stir and mix evenly to obtain a mixed material; Transport the mixture to an extruder, evenly coat the molten extruded liquid on both sides of the polyester fiber cloth, control the thickness of the surface glue to 7 mm, and obtain a high-strength wear-resistant and flame-retardant conveyor belt after hot pressing and cooling.

[0032] Example 3: A high-strength wear-resistant and flame-retardant conveyor belt, comprising a conveyor belt rubber material and a polyester fiber cloth inside the conveyor belt rubber material. The conveyor belt rubber material comprises the following components by weight: 140 parts of modified polyvinyl chloride, 25 parts of chloroprene rubber, 5 parts of modified hydrotalcite flame retardant, 2 parts of sodium dodecyl sulfate, 2 parts of zinc stearate, and 2 parts of N-phenyl-β-naphthylamine.

[0033] The preparation method of the modified hydrotalcite flame retardant comprises the following steps: 1) Add 10 g of hydrotalcite to 200 mL of deionized water, disperse it evenly by ultrasonic oscillation to obtain a hydrotalcite suspension; 2) Add 5 g of 3-sulfopropyl glycidyl ether to 100 mL of deionized water and stir to dissolve it to obtain a 3-sulfopropyl glycidyl ether solution; 3) Drop the 3-sulfopropyl glycidyl ether solution into the hydrotalcite suspension, heat and stir the reaction at 45 °C for 3 h, and obtain 3-sulfopropyl glycidyl ether intercalated hydrotalcite after centrifugal separation, washing and drying; 4) Add 7 g of carboxymethyl chitosan to 200 mL of deionized water and stir to dissolve it to obtain a carboxymethyl chitosan aqueous solution. Add 10 g of 3-sulfopropyl glycidyl ether intercalated hydrotalcite to the carboxymethyl chitosan aqueous solution, heat to 75 °C, stir and react for 3 h, and obtain a modified hydrotalcite flame retardant after centrifugal separation, washing and drying.

[0034] The preparation method of the modified polyvinyl chloride comprises the following steps: a) Add polyvinyl chloride powder to an oven and dry it at 60 °C for 4 h to remove moisture and volatile impurities, and set aside; b) Add 10 g of hydroxyethyl acrylate to 150 mL of toluene, stir to dissolve it, then add a benzoyl peroxide initiator, and the addition amount of benzoyl peroxide is 2.0 wt% of hydroxyethyl acrylate, stir evenly to obtain a mixed solution; c) Add the dried polyvinyl chloride powder to the above mixed solution, and the mass ratio of polyvinyl chloride powder to hydroxyethyl acrylate is 1:0.65. Heat to 83 °C, stir and react for 4 h, cool to room temperature, and then add a sodium hydroxide solution (100 mL of 10% sodium hydroxide solution) to neutralize acidic substances and precipitate the product; d) After suction filtration separation, washing and drying, obtain modified polyvinyl chloride.

[0035] A preparation method of a high-strength wear-resistant and flame-retardant conveyor belt comprises the following steps: Mix modified polyvinyl chloride, chloroprene rubber, modified hydrotalcite flame retardant, sodium dodecyl sulfate, zinc stearate, and N-phenyl-β-naphthylamine in a blender until evenly mixed to obtain a mixed material. Transport the mixed material to an extruder, and evenly coat the molten extruded liquid on both sides of the polyester fiber cloth. Control the thickness of the surface glue to be 7 mm. After hot pressing and cooling, a high-strength wear-resistant flame-retardant conveyor belt is obtained.

[0036] Example 4: A high-strength wear-resistant flame-retardant conveyor belt, comprising conveyor belt rubber and a polyester fiber cloth inside the conveyor belt rubber. The conveyor belt rubber comprises the following components by weight: 160 parts of modified polyvinyl chloride, 30 parts of chloroprene rubber, 7 parts of modified hydrotalcite flame retardant, 3 parts of sodium dodecyl sulfate, 3 parts of zinc stearate, and 3 parts of N-phenyl-β-naphthylamine.

[0037] The preparation method of the modified hydrotalcite flame retardant comprises the following steps: 1) Add 10 g of hydrotalcite to 200 mL of deionized water, and disperse it evenly by ultrasonic oscillation to obtain a hydrotalcite suspension. 2) Add 8 g of 3-sulfopropyl glycidyl ether to 100 mL of deionized water and stir to dissolve to obtain a 3-sulfopropyl glycidyl ether solution. 3) Drop the 3-sulfopropyl glycidyl ether solution into the hydrotalcite suspension, heat and stir the reaction at 45 °C for 3 h, and after centrifugal separation, washing and drying, obtain 3-sulfopropyl glycidyl ether intercalated hydrotalcite. 4) Add 10 g of carboxymethyl chitosan to 200 mL of deionized water and stir to dissolve to obtain a carboxymethyl chitosan aqueous solution. Add 10 g of 3-sulfopropyl glycidyl ether intercalated hydrotalcite to the carboxymethyl chitosan aqueous solution, heat to 80 °C, stir and react for 4 h, and after centrifugal separation, washing and drying, obtain the modified hydrotalcite flame retardant.

[0038] The preparation method of the modified polyvinyl chloride comprises the following steps: a) Add polyvinyl chloride powder to an oven and dry it at 60 °C for 4 h to remove moisture and volatile impurities, and set aside. b) Add 10 g of 2-hydroxyethyl acrylate to 150 mL of toluene, stir to dissolve, then add a benzoyl peroxide initiator, and the addition amount of benzoyl peroxide is 3.0 wt% of 2-hydroxyethyl acrylate, stir evenly to obtain a mixed solution. c) Add the dried polyvinyl chloride powder to the above mixed solution, and the mass ratio of polyvinyl chloride powder to 2-hydroxyethyl acrylate is 1:0.8. Heat to 85 °C, stir and react for 5 h, and after cooling to room temperature, add a sodium hydroxide solution (100 mL of 10% sodium hydroxide solution) to neutralize acidic substances and precipitate the product. d) After suction filtration separation, washing and drying, modified polyvinyl chloride is obtained.

[0039] A preparation method of a high-strength wear-resistant flame-retardant conveyor belt includes the following steps: Put modified polyvinyl chloride, chloroprene rubber, modified hydrotalcite flame retardant, sodium dodecyl sulfate, zinc stearate, and N-phenyl-β-naphthylamine into a mixer and stir and mix evenly to obtain a mixed material; Transport the mixed material to an extruder, evenly coat the molten extruded material liquid on both sides of the polyester fiber cloth, control the surface rubber thickness at 7 mm, and after hot pressing and cooling, obtain a high-strength wear-resistant flame-retardant conveyor belt.

[0040] Example 5: A high-strength wear-resistant flame-retardant conveyor belt, including a conveyor belt rubber material and a polyester fiber cloth inside the conveyor belt rubber material. The conveyor belt rubber material includes the following components by weight: 120 parts of modified polyvinyl chloride, 20 parts of chloroprene rubber, 3 parts of modified hydrotalcite flame retardant, 1 part of sodium dodecyl sulfate, 1 part of zinc stearate, and 1 part of N-phenyl-β-naphthylamine.

[0041] The preparation method of the modified hydrotalcite flame retardant includes the following steps: 1) Add 10 g of hydrotalcite to 200 mL of deionized water, disperse evenly by ultrasonic oscillation to obtain a hydrotalcite suspension; 2) Add 3 g of 3-sulfopropyl glycidyl ether to 100 mL of deionized water and stir to dissolve to obtain a 3-sulfopropyl glycidyl ether solution; 3) Drop the 3-sulfopropyl glycidyl ether solution into the hydrotalcite suspension, heat and stir at 45 °C for 3 h, and after centrifugal separation, washing and drying, obtain 3-sulfopropyl glycidyl ether intercalated hydrotalcite; 4) Add 5 g of carboxymethyl chitosan to 200 mL of deionized water and stir to dissolve to obtain a carboxymethyl chitosan aqueous solution. Add 10 g of 3-sulfopropyl glycidyl ether intercalated hydrotalcite to the carboxymethyl chitosan aqueous solution, heat to 70 °C, stir and react for 2 h, and after centrifugal separation, washing and drying, obtain the modified hydrotalcite flame retardant.

[0042] The preparation method of modified polyvinyl chloride includes the following steps: a) Put polyvinyl chloride powder into an oven and dry at 60 °C for 4 h to remove moisture and volatile impurities, and set aside; b) Add 10 g of hydroxyethyl acrylate to 150 mL of toluene, stir to dissolve, then add benzoyl peroxide initiator, and the addition amount of benzoyl peroxide is 0.5 wt% of hydroxyethyl acrylate, stir evenly to obtain a mixed solution; c) Add the dried polyvinyl chloride powder to the above mixed solution. The mass ratio of the polyvinyl chloride powder to hydroxyethyl acrylate is 1:0.5. Heat to 80 °C, stir and react for 3 h. After cooling to room temperature, add sodium hydroxide solution (100 mL of 10% sodium hydroxide solution) to neutralize acidic substances and precipitate the product; d) After filtration, washing and drying, the modified polyvinyl chloride is obtained.

[0043] A preparation method of a high-strength wear-resistant and flame-retardant conveyor belt includes the following steps: Add the modified polyvinyl chloride, chloroprene rubber, modified hydrotalcite flame retardant, sodium dodecyl sulfate, zinc stearate, and N-phenyl-β-naphthylamine into a blender and stir and mix evenly to obtain a mixture; Transport the mixture to an extruder, and evenly coat the molten extruded liquid on both sides of the polyester fiber cloth. The thickness of the surface rubber is controlled at 7 mm. After hot pressing and cooling, a high-strength wear-resistant and flame-retardant conveyor belt is obtained.

[0044] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that: The modified hydrotalcite flame retardant is not added to the conveyor belt rubber compound, and the remaining operation steps are the same as those in Example 1.

[0045] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that: The modified hydrotalcite flame retardant is replaced with ordinary hydrotalcite; and the remaining operation steps are the same as those in Example 1.

[0046] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that: Step 4) is omitted in the preparation process of the modified hydrotalcite, that is, carboxymethyl chitosan grafted 3-sulfopropyl glycidyl ether intercalated hydrotalcite is not used; and the remaining operation steps are the same as those in Example 1.

[0047] Comparative Example 4 The difference between Comparative Example 4 and Example 1 is that: The modified polyvinyl chloride is replaced with ordinary polyvinyl chloride; and the remaining operation steps are the same as those in Example 1.

[0048] Performance test The performance tests were carried out on the conveyor belts prepared in Examples 1-5 and Comparative Examples 1-4. The tensile strength of the conveyor belt was tested according to the method specified in GB / T528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber". The wear resistance of the conveyor belt was tested according to the method specified in GB / T9867-2006, and the wear amount generated by the cylindrical specimen within the specified distance of the gauze was determined. The flame retardancy of the conveyor belt was tested according to GB / T10707-2008 "Determination of rubber combustion properties", and the test results are as follows:

[0049] The above are only the preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as limiting the present invention, and the protection scope of the present invention should be subject to the scope defined by the claims. For those of ordinary skill in the art, without departing from the spirit and scope of the present invention, several improvements and modifications can also be made, and these improvements and modifications should also be regarded as within the protection scope of the present invention.

Claims

1. A high-strength wear-resistant and flame-retardant conveyor belt, characterized in that: The invention comprises a conveyor belt rubber material and a polyester fiber cloth located inside the conveyor belt rubber material, wherein the conveyor belt rubber material comprises the following components in parts by weight: 120-160 parts of modified polyvinyl chloride, 20-30 parts of chloroprene rubber, 3-7 parts of modified hydrotalcite flame retardant, 1-3 parts of sodium lauryl sulfate, 1-3 parts of zinc stearate, and 1-3 parts of N-phenyl-β-naphthylamine.

2. A high-strength wear-resistant and flame-retardant conveyor belt according to claim 1, characterized in that: The modified hydrotalcite flame retardant comprises the following steps: 1) adding hydrotalcite into deionized water and dispersing the water uniformly by ultrasonic oscillation to obtain a hydrotalcite suspension; 2) adding 3-sulfonate propyl glycidyl ether into water and stirring to dissolve, thereby obtaining a 3-sulfonate propyl glycidyl ether solution; 3) adding the 3-sulfonic acid propyl glycidyl ether solution dropwise into the hydrotalcite suspension, heating and stirring to react, and then centrifuging, washing and drying to obtain the 3-sulfonic acid propyl glycidyl ether intercalated hydrotalcite; 4) adding carboxymethyl chitosan into deionized water and stirring to dissolve to obtain a carboxymethyl chitosan aqueous solution, adding 3-sulfonic acid propyl glycidyl ether intercalated hydrotalcite into the carboxymethyl chitosan aqueous solution, heating and stirring to react, and performing centrifugal separation, washing and drying to obtain a modified hydrotalcite flame retardant.

3. A high-strength wear-resistant and flame-retardant conveyor belt according to claim 2, characterized in that: In the step 3), the mass ratio of hydrotalcite to 3-sulfonic acid propyl glycidyl ether is 1:0.3-0.

8.

4. A high-strength wear-resistant and flame-retardant conveyor belt according to claim 2, characterized in that: In the step 4), the mass ratio of 3-sulfonic acid propyl glycidyl ether intercalated hydrotalcite to carboxymethyl chitosan is 1:0.5-1.

5. The high-strength wear-resistant and flame-retardant conveyor belt according to claim 1, characterized in that: In the step 4), the heating reaction temperature is 70-80° C., and the stirring reaction time is 2-4 hours.

6. A high-strength wear-resistant and flame-retardant conveyor belt according to claim 1, characterized in that: The preparation method of the modified polyvinyl chloride comprises the following steps: a) Add polyvinyl chloride powder into an oven for drying to remove moisture and volatile impurities, and set aside; b) adding hydroxyethyl acrylate to toluene, stirring to dissolve, then adding benzoyl peroxide initiator, stirring evenly to obtain a mixed solution; c) adding the dried polyvinyl chloride powder to the mixed solution, heating and stirring to react, and after cooling to room temperature, adding sodium hydroxide solution to neutralize the acidic substances and precipitate the product; d) After separation by suction filtration, washing and drying, modified polyvinyl chloride is obtained.

7. A high-strength wear-resistant and flame-retardant conveyor belt according to claim 6, characterized in that: In the step b), the added amount of benzoyl peroxide is 0.5-3.0 wt % of hydroxyethyl acrylate.

8. The high-strength wear-resistant and flame-retardant conveyor belt according to claim 6, characterized in that: In the step c), the mass ratio of polyvinyl chloride to hydroxyethyl acrylate is 1:0.5-0.

8.

9. A high-strength wear-resistant and flame-retardant conveyor belt according to claim 6, characterized in that: In the step c), the heating reaction temperature is 80-85° C. and the reaction time is 3-5 hours.

10. A method for preparing a high-strength wear-resistant and flame-retardant conveyor belt according to any one of claims 1 to 9, characterized in that: The following steps are involved: Add modified polyvinyl chloride, chloroprene rubber, modified hydrotalcite flame retardant, sodium lauryl sulfate, zinc stearate, and N-phenyl-β-naphthylamine into a blender and mix them evenly to obtain a mixture; The mixed material is conveyed to an extruder, and the molten extruded material liquid is evenly coated on both sides of the polyester fiber cloth. After hot pressing and cooling, a high-strength wear-resistant and flame-retardant conveyor belt is obtained.

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