A dynamically vulcanized fabric core flame resistant conveyor belt and method of making same

Abstract

The application discloses a kind of dynamic vulcanized fabric whole core flame-retardant conveyor belt and manufacturing method thereof, including cover layer and fabric whole belt core;Cover layer includes the following components: polyvinyl chloride resin, cis+6 butadiene rubber, thermoplastic polyurethane elastomer, ethylene-octene copolymer, zinc oxide, diantimony trioxide, composite hybrid flame-retardant material, dioctyl phthalate, tris (2-carboxyethyl) phosphine, calcium-zinc composite stabilizer and auxiliary agent;The application is prepared by compounding expanded graphite, aluminum diethyl hypophosphite, melamine polyphosphate and 2-methyl imidazole zinc salt, first by surface treatment of polymeric ionic liquid to prepare composite hybrid flame-retardant material, the modification of polymeric ionic liquid to metal-organic framework material 2-methyl imidazole zinc salt surface, enhance the antistatic ability of 2-methyl imidazole zinc salt, the cover layer compound prepared has excellent flame-retardant antistatic performance and mechanical property and the adhesion with belt core.

Description

Technical Field

[0001] This invention belongs to the field of conveyor belt technology, specifically relating to a dynamically vulcanized solid-core flame-retardant conveyor belt and its manufacturing method. Background Technology

[0002] Rubber-faced solid woven flame-retardant belts are a major tool for coal transportation in underground coal mines. Existing technologies for forming the cover rubber of these belts employ two production processes: one is a calendering, molding, and flat vulcanization process. The advantage of this process is a thicker cover layer with better mechanical properties, but the disadvantages are poor adhesion between the cover layer and the belt core, affecting service life, low production efficiency, and high energy consumption. The other process is an extrusion lamination molding process. The advantages of this process are high production efficiency and low energy consumption, but the disadvantages are a thin cover layer (difficult to form when the cover layer exceeds 3mm), low rubber content, and a simple mixture with polyvinyl chloride (PVC). The rubber's role is merely to increase compatibilization and plasticize, resulting in poor mechanical properties and a shorter service life for the cover layer.

[0003] Patent CN107216560A discloses an aramid fabric solid core flame-retardant conveyor belt and its manufacturing method. By using a PVC / CM / TPU blended thermoplastic elastomer in the cover layer, the flame-retardant and mechanical properties of the conveyor belt are improved. The three-layer structure of the fabric solid core reduces the weight of the core, reduces the transport loss and energy consumption of the conveyor belt, and improves the bonding strength between the core and the cover layer.

[0004] However, the performance of the flame-retardant conveyor belt produced by this method is highly dependent on the dispersibility of the flame retardant, and the extensive use of silane coupling agents will also generate VOCs, which will have an impact on the environment. Summary of the Invention

[0005] One of the objectives of this invention is to provide a dynamically vulcanized solid woven flame-retardant conveyor belt to solve the problem of how to make the cover layer have excellent flame-retardant and antistatic properties and mechanical properties at the same time, and improve the adhesion performance and service life of the cover layer and the belt core.

[0006] The second objective of this invention is to provide a method for manufacturing a dynamically vulcanized solid-core flame-retardant conveyor belt, in order to solve the problems of simplifying the manufacturing process, reducing energy consumption, and improving production efficiency.

[0007] The objective of this invention can be achieved through the following technical solutions:

[0008] A dynamically vulcanized solid fabric flame-retardant conveyor belt includes a cover layer and a solid fabric belt core;

[0009] The coating layer, by weight, comprises the following components:

[0010] 30-40 parts polyvinyl chloride resin (PVC), 30-40 parts butadiene rubber (BR), 10-20 parts thermoplastic polyurethane elastomer (TPU), 10-20 parts ethylene-octene copolymer (POE), 2-4 parts zinc oxide, 1-2 parts stearic acid, 0.6-1 parts sulfur, 1.5-2 parts accelerator, 1.5-2 parts antioxidant, 12-16 parts carbon black, 6-8 parts antimony trioxide, 40-50 parts composite hybrid flame retardant material, 12-16 parts dioctyl phthalate (DOP), 8-12 parts tris(2-carboxyethyl)phosphine (TCEP), 4-6 parts paraffin oil, 2-5 parts antistatic agent, and 2-5 parts calcium-zinc composite stabilizer.

[0011] The integral fabric core is made by impregnating and plasticizing the integral core.

[0012] Furthermore, the composite hybrid flame retardant material is prepared by the following steps:

[0013] Expanded graphite (EG), aluminum diethyl phosphite (ADP), melamine polyphosphate (MPP), and 2-methylimidazolium zinc salt are added to a kneader and heated to 40-60℃ at a speed of 350-400 rpm and stirred for 20-30 minutes. After spraying polymeric ionic liquid into the kneader, the temperature is raised to 105-110℃ and stirred for 10-15 minutes. After cooling, a composite hybrid flame retardant material is obtained.

[0014] Furthermore, the mass ratio of expanded graphite, diethylaluminum hypophosphite, melamine polyphosphate, 2-methylimidazolium zinc salt, and polymeric ionic liquid is 30-35:30-35:20-25:2.5-3.5:1.5-2.5.

[0015] Furthermore, the polymeric ionic liquid is one of 1-ethyl-3-methylimidazolium phosphate, 1-ethyl-3-methylimidazolium phosphate, or 1-butyl-3-methylimidazolium phosphate.

[0016] Furthermore, the accelerator is prepared by mixing 2-mercaptobenzothiazole (M), 2,2'-dithiodibenzothiazole (DM) and tetramethylthiuram disulfide (TMTD) in a mass ratio of 3-6:5-8.

[0017] Furthermore, the antioxidant is prepared by mixing 2,2,4-trimethyl-1,2-dihydroquinoline polymer (RD) and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (TMTD) in a mass ratio of 5-6:7-8.

[0018] Furthermore, the antistatic agent is one of polydimethylsiloxane, methyl silicone oil, and sodium chloride.

[0019] A method for manufacturing a dynamically vulcanized solid-core flame-retardant conveyor belt includes the following steps:

[0020] Step 1: Add the composite flame retardant material to the internal mixer and heat it to 70-80℃ at a speed of 40-60 rpm. Then add cis-butadiene rubber and blend for 4-5 minutes. The discharge temperature is 140-145℃. Sheet the material and cool it to room temperature. After standing for 8-10 hours, the composite flame retardant masterbatch is obtained.

[0021] Step 2: Add polyvinyl chloride resin, dioctyl phthalate, antimony trioxide, antistatic agent and calcium-zinc composite stabilizer to a high-speed kneader in sequence. Mix at a speed of 1200-1400 rpm and at a temperature of 135-145℃ for 10-15 minutes. After discharging and cooling, the pre-plasticized material is obtained.

[0022] Step 3: The hybrid flame-retardant masterbatch obtained in Step 1, the preplasticizer obtained in Step 2, the thermoplastic polyurethane elastomer, the ethylene-octene copolymer, zinc oxide, stearic acid, sulfur, accelerator, antioxidant, carbon black, tris(2-carboxyethyl)phosphine, and paraffin oil are sequentially added to a mixing mill and mixed at a speed of 40-50 rpm. The mixture is then dynamically vulcanized at 170-175℃ for 3-4 minutes. After that, it is passed through a twin-screw extruder at a screw speed of 50-70 rpm and dynamically vulcanized at 170-175℃ for 5-6 minutes. The mixture is then granulated and cooled to obtain the cover layer compound.

[0023] Step 4: After the covering layer granules are dynamically vulcanized by two extruders and a die, they are directly bonded to the fabric core under heat. The extruder speed is 50-60 rpm, the extruder temperature is 160-175℃, the die temperature is 160-175℃, and the core surface temperature is 145-165℃, resulting in a dynamically vulcanized fabric core flame-retardant conveyor belt.

[0024] Furthermore, the integral fabric core is prepared by the following steps:

[0025] A sizing agent is prepared by mixing polyethylene paste resin, dioctyl phthalate, epoxidized soybean oil, medium-chain chlorinated paraffin, tris(2-carboxyethyl)phosphine, aluminum hydroxide, antimony trioxide, and calcium-zinc composite stabilizer. The sizing agent is then woven into an integral belt core using polyester / cotton fibers. The integral belt core is then impregnated with the sizing agent to obtain the integral fabric belt core.

[0026] Furthermore, the overall core of the fabric has a glue content of 50-60%, a plasticizing temperature of 160-170℃, and a plasticizing time of 2 min / mm.

[0027] Furthermore, the impregnation formulation, by weight, comprises the following components:

[0028] 100-120 parts polyethylene paste resin, 50-60 parts dioctyl phthalate, 10-15 parts epoxidized soybean oil, 10-20 parts medium-chain chlorinated paraffin, 15-25 parts tris(2-carboxyethyl)phosphine, 5-10 parts aluminum hydroxide, 5-6 parts antimony trioxide and 5-6 parts calcium-zinc composite stabilizer.

[0029] The beneficial effects of this invention are:

[0030] (1) The dynamically vulcanized fabric core flame-retardant conveyor belt prepared by the present invention is prepared by first preparing a composite flame-retardant material by combining expanded graphite, aluminum diethyl hypophosphite, melamine polyphosphate and 2-methylimidazolium zinc salt, and then surface treating it with a polymeric ionic liquid. The surface of the metal-organic framework material 2-methylimidazolium zinc salt is modified by the polymeric ionic liquid to enhance the antistatic ability of 2-methylimidazolium zinc salt. The resulting cover layer rubber has excellent flame-retardant and antistatic properties, mechanical properties and adhesion to the belt core.

[0031] (2) The dynamically vulcanized fabric solid flame retardant conveyor belt prepared by the present invention improves the compatibility of composite hybrid flame retardant masterbatch with preplasticizer, thermoplastic polyurethane elastomer and other additives by adding ethylene-octene copolymer, and at the same time reduces the processing temperature of the blend, thereby improving the flame retardant performance, mechanical properties, adhesive properties and processing performance of the cover layer rubber.

[0032] (3) The dynamically vulcanized fabric solid flame-retardant conveyor belt prepared by the present invention, by adding 2-methylimidazolium zinc salt, makes the cover layer rubber material form a relatively dense char layer during flame retardancy, promotes char formation to isolate heat and oxygen, effectively improves the flame retardant performance of the cover layer rubber material. The addition of 2-methylimidazolium zinc salt can also prevent the agglomeration of composite hybrid flame retardant materials, improve the compatibility and dispersibility between composite hybrid flame retardant materials and cover layer rubber material. In addition to improving the flame retardant performance of the cover layer rubber material, it also improves the thermal stability, electrical conductivity and mechanical properties of the cover layer rubber material.

[0033] (4) The dynamically vulcanized fabric solid flame retardant conveyor belt prepared by the present invention uses polymeric ionic liquid to replace silane coupling agent to modify the composite hybrid flame retardant material, which can reduce the emission of VOCs in the modification process and subsequent processing, which is beneficial to environmental protection. It also improves the dispersion degree of composite hybrid flame retardant material, and at the same time improves the flame retardant, antistatic and mechanical properties of the covering layer rubber.

[0034] (5) The coating material prepared by the present invention is composed of composite hybrid flame retardant material, antimony trioxide and tris(2-carboxyethyl)phosphine to form a flame retardant system, which has a synergistic effect and can simultaneously improve the flame retardant, antistatic and mechanical properties of the coating layer.

[0035] (6) The manufacturing method of the present invention adopts extrusion molding and dynamic vulcanization process, which realizes the continuous production of conveyor belt. Compared with calendering, molding and flat vulcanization process, it saves energy consumption, improves production efficiency, and is simple and easy to manufacture. Detailed Implementation

[0036] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0037] Example 1: A dynamically vulcanized solid fabric flame-retardant conveyor belt, comprising a cover layer and a solid fabric core.

[0038] The integral fabric core is made by impregnating and plasticizing the integral core.

[0039] A method for manufacturing a dynamically vulcanized solid-core flame-retardant conveyor belt includes the following steps:

[0040] S1. Add 30kg of expanded graphite, 30kg of diethyl aluminum hypophosphite, 20kg of melamine polyphosphate and 2.5kg of 2-methylimidazolium zinc salt to a kneader, heat to 40℃ at 350rpm and stir for 20min. Spray 1.5kg of polymeric ionic liquid into the kneader and heat to 105℃ and stir for 10min. After cooling, a composite hybrid flame retardant material is obtained.

[0041] S2. Add 40kg of composite flame retardant material to a mixer and heat it to 70℃ at 40rpm. Then add 30kg of butadiene rubber and blend for 4min. The discharge temperature is 140℃. Sheet the material, cool it to room temperature, and let it stand for 8h to obtain the composite flame retardant masterbatch.

[0042] S3. Add 30kg of polyvinyl chloride resin, 12kg of dioctyl phthalate, 6kg of antimony trioxide, 2kg of polydimethylsiloxane and 2kg of calcium-zinc composite stabilizer to a high-speed kneader in sequence. Mix at 1200rpm and at 135℃ for 10min. After discharge and cooling, the pre-plasticized material is obtained.

[0043] S4. The hybrid flame-retardant masterbatch obtained in S2, the preplasticizer obtained in S3, 10 kg of thermoplastic polyurethane elastomer, 10 kg of ethylene-octene copolymer, 2 kg of zinc oxide, 1 kg of stearic acid, 0.6 kg of sulfur, 1.5 kg of accelerator, 1.5 kg of antioxidant, 12 kg of carbon black N220, 8 kg of tris(2-carboxyethyl)phosphine and 4 kg of paraffin oil are added sequentially into a mixing mill and mixed at 40 rpm. The mixture is dynamically vulcanized at 170°C for 3 min. Then, it is passed through a twin-screw extruder at 50 rpm and dynamically vulcanized at 170°C for 5 min. After granulation and cooling, the cover layer rubber compound is obtained.

[0044] S5. Mix 100 kg of polyethylene paste resin, 50 kg of dioctyl phthalate, 10 kg of epoxidized soybean oil, 10 kg of medium-chain chlorinated paraffin, 15 kg of tris(2-carboxyethyl)phosphine, 5 kg of aluminum hydroxide, 5 kg of antimony trioxide, and 5 kg of calcium-zinc composite stabilizer to prepare an impregnation agent. Weave the impregnation agent into an integral belt core using polyester / cotton fibers. Impregnate and plasticize the integral belt core to obtain an integral fabric belt core. The integral fabric belt core has an impregnation agent content of 50%, a plasticizing temperature of 160℃, and a plasticizing time of 2 min / mm.

[0045] S6. The granular material of the cover layer is dynamically vulcanized by two extruders and a die and then directly bonded to the whole fabric core under heat. The speed of the extruder is 50 rpm, the temperature of the extruder is 160℃, the temperature of the die is 160℃, and the surface temperature of the core is 145℃, so as to obtain a dynamically vulcanized whole fabric flame-retardant conveyor belt.

[0046] The accelerator is prepared by mixing 2-mercaptobenzothiazole (M), 2,2'-dithiodibenzothiazole (DM) and tetramethylthiuram disulfide (TMTD) in a mass ratio of 3-6:5-8.

[0047] The antioxidant is prepared by mixing 2,2,4-trimethyl-1,2-dihydroquinoline polymer (antioxidant RD) and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (antioxidant 4020) in a mass ratio of 5-6:7-8.

[0048] Example 2: A dynamically vulcanized solid fabric flame-retardant conveyor belt, comprising a cover layer and a solid fabric core.

[0049] The integral fabric core is made by impregnating and plasticizing the integral core.

[0050] A method for manufacturing a dynamically vulcanized solid-core flame-retardant conveyor belt includes the following steps:

[0051] S1. Add 32.5 kg of expanded graphite, 32.5 kg of aluminum diethyl phosphite, 22.5 kg of melamine polyphosphate and 3 kg of 2-methylimidazolium zinc salt to a kneader, heat to 50°C at 370 rpm and stir for 25 min. Spray 2 kg of polymeric ionic liquid into the kneader and heat to 107°C and stir for 12.5 min. After cooling, a composite hybrid flame retardant material is obtained.

[0052] S2. Add 45kg of composite flame retardant material to a mixer and heat it to 75℃ at 50rpm. Then add 35kg of butadiene rubber and blend for 4.5min. The discharge temperature is 142.5℃. Sheet the material, cool it to room temperature, and let it stand for 9h to obtain the composite flame retardant masterbatch.

[0053] S3. Add 35kg of polyvinyl chloride resin, 14kg of dioctyl phthalate, 7kg of antimony trioxide, 3.5kg of methyl silicone oil and 3.5kg of calcium-zinc composite stabilizer to a high-speed kneader in sequence. Mix at 1300rpm and at 140℃ for 12.5min. After discharge and cooling, the pre-plasticized material is obtained.

[0054] S4. The hybrid flame-retardant masterbatch obtained in S2, the preplasticizer obtained in S3, 15 kg of thermoplastic polyurethane elastomer, 15 kg of ethylene-octene copolymer, 3 kg of zinc oxide, 1.5 kg of stearic acid, 0.8 kg of sulfur, 1.75 kg of accelerator, 1.75 kg of antioxidant, 14 kg of carbon black N234, 10 kg of tris(2-carboxyethyl)phosphine and 5 kg of paraffin oil are sequentially added to a mixing mill and mixed at a speed of 45 rpm. The mixture is dynamically vulcanized at 173°C for 3.5 min. Then, it is passed through a twin-screw extruder at a screw speed of 60 rpm and dynamically vulcanized at 173°C for 5.5 min. After granulation and cooling, the cover layer rubber compound is obtained.

[0055] S5. Mix 110 kg of polyethylene paste resin, 55 kg of dioctyl phthalate, 12.5 kg of epoxidized soybean oil, 15 kg of medium-chain chlorinated paraffin, 20 kg of tris(2-carboxyethyl)phosphine, 7.5 kg of aluminum hydroxide, 5.5 kg of antimony trioxide, and 5.5 kg of calcium-zinc composite stabilizer to prepare an impregnation agent. Weave polyester / cotton fibers into an integral belt core, impregnate the integral belt core with the agent, and plasticize it to obtain a fabric integral belt core. The adhesive content of the fabric integral belt core is 55%, the plasticizing temperature is 165℃, and the plasticizing time is 2 min / mm.

[0056] S6. The granular material of the covering layer is dynamically vulcanized by two extruders and a die and then directly bonded to the whole fabric core under hot conditions. The speed of the extruder is 55 rpm, the temperature of the extruder is 170℃, the temperature of the die is 170℃, and the surface temperature of the core is 150℃, so as to obtain a dynamically vulcanized whole fabric flame-retardant conveyor belt.

[0057] The accelerator is prepared by mixing 2-mercaptobenzothiazole (M), 2,2'-dithiodibenzothiazole (DM) and tetramethylthiuram disulfide (TMTD) in a mass ratio of 3-6:5-8.

[0058] The antioxidant is prepared by mixing 2,2,4-trimethyl-1,2-dihydroquinoline polymer (antioxidant RD) and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (antioxidant 4020) in a mass ratio of 5-6:7-8.

[0059] Example 3: A dynamically vulcanized solid fabric flame-retardant conveyor belt, comprising a cover layer and a solid fabric core.

[0060] The integral fabric core is made by impregnating and plasticizing the integral core.

[0061] A method for manufacturing a dynamically vulcanized solid-core flame-retardant conveyor belt includes the following steps:

[0062] S1. Add 35kg of expanded graphite, 35kg of diethyl aluminum hypophosphite, 25kg of melamine polyphosphate and 3.5kg of 2-methylimidazolium zinc salt to a kneader, heat to 60℃ at 400rpm and stir for 30min. Spray 2.5kg of polymeric ionic liquid into the kneader and heat to 110℃ and stir for 15min. After cooling, a composite hybrid flame retardant material is obtained.

[0063] S2. Add 50kg of composite flame retardant material to a mixer and heat it to 80℃ at 60rpm. Then add 40kg of butadiene rubber and blend for 5min. The discharge temperature is 145℃. Sheet the material, cool it to room temperature, and let it stand for 10h to obtain the composite flame retardant masterbatch.

[0064] S3. Add 40 kg of polyvinyl chloride resin, 16 kg of dioctyl phthalate, 8 kg of antimony trioxide, 5 kg of sodium chloride and 5 kg of calcium-zinc composite stabilizer to a high-speed kneader in sequence. Mix at 1400 rpm and at 145°C for 15 min. After discharge and cooling, the pre-plasticized material is obtained.

[0065] S4. The hybrid flame-retardant masterbatch obtained in S2, the preplasticizer obtained in S3, 20 kg of thermoplastic polyurethane elastomer, 20 kg of ethylene-octene copolymer, 4 kg of zinc oxide, 2 kg of stearic acid, 1 kg of sulfur, 2 kg of accelerator, 2 kg of antioxidant, 16 kg of carbon black N330, 12 kg of tris(2-carboxyethyl)phosphine and 6 kg of paraffin oil are added sequentially into a mixing mill and mixed at 50 rpm. The mixture is dynamically vulcanized at 175°C for 4 min. Then it is passed through a twin-screw extruder at 70 rpm and dynamically vulcanized at 175°C for 6 min. After granulation and cooling, the cover layer rubber compound is obtained.

[0066] S5. Mix 120kg polyethylene paste resin, 60kg dioctyl phthalate, 15kg epoxidized soybean oil, 20kg medium-chain chlorinated paraffin, 25kg tris(2-carboxyethyl)phosphine, 10kg aluminum hydroxide, 6kg antimony trioxide, and 6kg calcium-zinc composite stabilizer to prepare an impregnation agent. Weave polyester / cotton fibers into an integral belt core. Impregnate and plasticize the integral belt core to obtain a fabric integral belt core. The adhesive content of the fabric integral belt core is 60%, the plasticizing temperature is 170℃, and the plasticizing time is 2min / mm.

[0067] S6. The granular material of the cover layer is dynamically vulcanized by two extruders and a die and then directly bonded to the whole fabric core under heat. The speed of the extruder is 60 rpm, the temperature of the extruder is 175℃, the temperature of the die is 175℃, and the surface temperature of the core is 165℃, so as to obtain a dynamically vulcanized whole fabric flame-retardant conveyor belt.

[0068] The accelerator is prepared by mixing 2-mercaptobenzothiazole (M), 2,2'-dithiodibenzothiazole (DM) and tetramethylthiuram disulfide (TMTD) in a mass ratio of 3-6:5-8.

[0069] The antioxidant is prepared by mixing 2,2,4-trimethyl-1,2-dihydroquinoline polymer (antioxidant RD) and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (antioxidant 4020) in a mass ratio of 5-6:7-8.

[0070] Comparative Example 1: The difference from Example 1 is that no polymeric ionic liquid is added in S1.

[0071] Comparative Example 2: The difference from Example 1 is that 2-methylimidazolium zinc salt is not added in S1.

[0072] Comparative Example 3: The difference from Example 1 is that ethylene-octene copolymer is not added in S4.

[0073] The performance of the cover layer rubber compounds prepared in Examples 1-3 and Comparative Examples 1-3 was tested. Tensile strength, elongation at break, abrasion loss, adhesion strength between the cover layer and the core, surface resistivity, and alcohol burner test were performed according to standard MT / T 914-2019. The results are shown in Table 1.

[0074]

[0075] As can be seen from Table 1, the cover layer rubber compound of the dynamically vulcanized fabric solid core flame retardant conveyor belt prepared by the present invention has good tensile strength, elongation at break and wear resistance, low surface resistance, good antistatic properties, short flame / no-flame burning time, fast extinguishing, good flame retardant ability, and high bonding strength with the fabric solid core, all of which meet the requirements of standard MT / T914-2019.

[0076] Because no polymeric ionic liquid was added to Comparative Example 1, the surface of the composite flame retardant was not modified, resulting in poor dispersibility. Consequently, Comparative Example 1 exhibited poor antistatic and flame retardant properties, but also low mechanical properties.

[0077] Comparative Example 2, due to the absence of 2-methylimidazolium zinc salt, showed less improvement in the antistatic properties of the cover layer compound, lost its synergistic effect with the flame retardant, and had poor flame retardant ability.

[0078] In Comparative Example 3, due to the absence of ethylene-octene copolymer, the composite hybrid flame retardant masterbatch had poor compatibility with preplasticizers, thermoplastic polyurethane elastomers, and other additives, resulting in reduced performance of the cover layer compound.

[0079] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A dynamically vulcanized solid-core flame-retardant conveyor belt, characterized in that, Includes the overlay and the fabric core; The coating layer comprises the following components by weight: 30-40 parts polyvinyl chloride resin, 30-40 parts butadiene rubber, 10-20 parts thermoplastic polyurethane elastomer, 10-20 parts ethylene-octene copolymer, 2-4 parts zinc oxide, 1-2 parts stearic acid, 0.6-1 part sulfur, 1.5-2 parts accelerator, 1.5-2 parts antioxidant, 12-16 parts carbon black, 6-8 parts antimony trioxide, 40-50 parts composite hybrid flame retardant material, 12-16 parts dioctyl phthalate, 8-12 parts tris(2-carboxyethyl)phosphine, 4-6 parts paraffin oil, 2-5 parts antistatic agent and 2-5 parts calcium-zinc composite stabilizer; The integral fabric core is obtained by impregnating and plasticizing an integral core. The composite flame retardant material is prepared by the following steps: expanded graphite, aluminum diethyl hypophosphite, melamine polyphosphate and 2-methylimidazolium zinc salt are put into a kneader and heated to 40-60℃ at a speed of 350-400 rpm and stirred for 20-30 min. After spraying polymeric ionic liquid into the kneader, the temperature is raised to 105-110℃ and stirred for 10-15 min. After cooling, the composite flame retardant material is obtained. The mass ratio of expanded graphite, diethylaluminum hypophosphite, melamine polyphosphate, 2-methylimidazolium zinc salt, and polymeric ionic liquid is 30-35:30-35:20-25:2.5-3.5:1.5-2.5; The polymeric ionic liquid is one of 1-ethyl-3-methylimidazolium phosphate, 1-ethyl-3-methylimidazolium phosphate, and 1-butyl-3-methylimidazolium phosphate.

2. The dynamically vulcanized solid-core flame-retardant conveyor belt according to claim 1, characterized in that, The antioxidant is prepared by mixing 2,2,4-trimethyl-1,2-dihydroquinoline polymer and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine in a mass ratio of 3-6:5-8.

3. The method for manufacturing a dynamically vulcanized solid-core flame-retardant conveyor belt according to claim 1, characterized in that, Includes the following steps: Step 1: Add the composite flame retardant material to the internal mixer and heat it to 70-80℃ at a speed of 40-60 rpm. Then add cis-butadiene rubber and mix for 4-5 minutes. The discharge temperature is 140-145℃. Sheet the material and cool it to room temperature. After standing for 8-10 hours, the composite flame retardant masterbatch is obtained. Step 2: Add polyvinyl chloride resin, dioctyl phthalate, antimony trioxide, antistatic agent and calcium-zinc composite stabilizer to a high-speed kneader in sequence. Mix at a speed of 1200-1400 rpm and at a temperature of 135-145℃ for 10-15 minutes. After discharging and cooling, the pre-plasticized material is obtained. Step 3: The hybrid flame retardant masterbatch obtained in Step 1, the preplasticizer obtained in Step 2, the thermoplastic polyurethane elastomer, the ethylene-octene copolymer, zinc oxide, stearic acid, sulfur, accelerator, antioxidant, carbon black, tris(2-carboxyethyl)phosphine and paraffin oil are sequentially added to a mixing mill and mixed at a speed of 40-50 rpm. The mixture is then dynamically vulcanized at 170-175℃ for 3-4 minutes. After that, it is passed through a twin-screw extruder at a screw speed of 50-70 rpm and dynamically vulcanized at 170-175℃ for 5-6 minutes. The mixture is then granulated and cooled to obtain the cover layer compound. Step 4: After the cover layer rubber compound is dynamically vulcanized by two extruders and a die, it is directly bonded to the fabric core under heat. The extruder speed is 50-60 rpm, the extruder temperature is 160-175℃, the die temperature is 160-175℃, and the core surface temperature is 145-165℃, to obtain a dynamically vulcanized fabric core flame-retardant conveyor belt.

4. The method for manufacturing a dynamically vulcanized solid-core flame-retardant conveyor belt according to claim 3, characterized in that, The integral fabric core is obtained by the following steps: A sizing agent is prepared by mixing polyethylene paste resin, dioctyl phthalate, epoxidized soybean oil, medium-chain chlorinated paraffin, tris(2-carboxyethyl)phosphine, aluminum hydroxide, antimony trioxide, and calcium-zinc composite stabilizer. The sizing agent is then woven into an integral belt core using polyester / cotton fibers. The integral belt core is then impregnated with the sizing agent to obtain the integral fabric belt core.

5. The method for manufacturing a dynamically vulcanized solid-core flame-retardant conveyor belt according to claim 4, characterized in that, The overall core of the fabric has a glue content of 50-60%, a plasticizing temperature of 160-170℃, and a plasticizing time of 2 min / mm.

6. The method for manufacturing a dynamically vulcanized solid-core flame-retardant conveyor belt according to claim 4, characterized in that, The impregnation formulation, by weight, comprises the following components: 100-120 parts polyethylene paste resin, 50-60 parts dioctyl phthalate, 10-15 parts epoxidized soybean oil, 10-20 parts medium-chain chlorinated paraffin, 15-25 parts tris(2-carboxyethyl)phosphine, 5-10 parts aluminum hydroxide, 5-6 parts antimony trioxide, and 5-6 parts calcium-zinc composite stabilizer.

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