Dynamically vulcanized fabric whole-core flame-retardant conveying belt and manufacturing method thereof

Abstract

The invention discloses a dynamically vulcanized fabric whole-core flame-retardant conveying belt and a manufacturing method thereof. The dynamically vulcanized fabric whole-core flame-retardant conveying belt comprises a covering layer and a fabric whole belt core, the covering layer comprises the following components: polyvinyl chloride resin, cis + 6 butadiene rubber, a thermoplastic polyurethane elastomer, an ethylene-octylene copolymer, zinc oxide, antimony trioxide, a composite hybrid flame-retardant material, dioctyl phthalate, tris (2-carboxyethyl) phosphine, a calcium-zinc composite stabilizer and an auxiliary agent; the preparation method comprises the following steps: compounding expanded graphite, aluminum diethylhypophosphite, melamine polyphosphate and 2-methylimidazole zinc salt, firstly, carrying out surface treatment on the compound through a polymeric ionic liquid to prepare a composite hybrid flame-retardant material, and modifying the surface of a metal organic framework material 2-methylimidazole zinc salt by using the polymeric ionic liquid. The anti-static capacity of the 2-methylimidazole zinc salt is enhanced, and the prepared covering layer sizing material has excellent flame-retardant and anti-static performance, mechanical performance and bonding performance with a belt core.

Description

Technical Field

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

[0002] Rubber-faced fabric whole-core flame-retardant belt is the main tool for coal transportation in coal mines. There are two production process methods for the covering rubber molding of rubber-faced fabric whole-core flame-retardant belt in the prior art: one is a calendering, molding, and flat-plate vulcanization process method, which has the advantages of a thicker covering layer and better mechanical properties, but has the disadvantages of poor adhesion between the covering layer and the belt core, which affects the service life, low production efficiency, and high energy consumption; the other is an extrusion veneer molding process method, which has the advantages of high production efficiency and low energy consumption, but has the disadvantages of a thin covering layer, which is difficult to mold when the covering layer exceeds 3mm, low rubber content, and is simply mixed with polyvinyl chloride. The role of the rubber is only to increase the volume and plasticize, so the mechanical properties of the covering layer are poor and the service life is short.

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

[0004] However, the performance of the flame-retardant conveyor belt produced by this scheme is more dependent on the dispersibility of the flame retardant, and the large-scale use of silane coupling agents will also produce VOCs, which will have an impact on the environment. Summary of the invention

[0005] One of the purposes of the present invention is to provide a dynamically vulcanized fabric whole core flame retardant conveyor belt to solve the problem of how to make the covering layer have excellent flame retardant and antistatic properties and mechanical properties, and improve the adhesion and service life of the covering layer and the belt core.

[0006] The second object of the present invention is to provide a method for manufacturing a dynamically vulcanized fabric whole-core flame-retardant conveyor belt to solve the problem of how to simplify the preparation process, reduce energy consumption and improve production efficiency.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] A dynamically vulcanized fabric integral core flame retardant conveyor belt, comprising a covering layer and a fabric integral belt core;

[0009] The covering layer comprises the following components by mass:

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

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

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

[0013] Expanded graphite (EG), diethyl aluminum hypophosphite (ADP), melamine polyphosphate (MPP) and 2-methylimidazole zinc salt are put into a kneader, heated to 40-60° C. at a rotation speed of 350-400 rpm and stirred for 20-30 minutes, and then the polymerized ionic liquid is sprayed into the kneader and the temperature is raised to 105-110° C. and stirred for 10-15 minutes. After cooling, a composite hybrid flame retardant material is obtained.

[0014] Furthermore, the mass ratio of expanded graphite, diethyl aluminum hypophosphite, melamine polyphosphate, 2-methylimidazole zinc salt and polymerized 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-methylimidazole dimethyl phosphate, 1-ethyl-3-methylimidazole diethyl phosphate, and 1-butyl-3-methylimidazole dibutyl phosphate.

[0016] Furthermore, the accelerator is prepared by mixing 2-mercaptobenzothiazole (M), 2,2'-dibenzothiazole disulfide (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] Further, the antistatic agent is one of polydimethylsiloxane, methyl silicone oil and sodium chloride.

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

[0020] Step 1: Add the composite hybrid flame retardant material into an internal mixer, heat to 70-80°C at a speed of 40-60rpm, then add butadiene rubber and blend for 4-5min, the discharge temperature is 140-145°C, sheet out, cool to room temperature, and stand for 8-10h to obtain a hybrid flame retardant masterbatch.

[0021] Step 2: Add polyvinyl chloride resin, dioctyl phthalate, antimony trioxide, antistatic agent and calcium zinc composite stabilizer into a high-speed kneader in sequence, with a mixing speed of 1200-1400 rpm, mix at a temperature of 135-145° C. for 10-15 minutes, discharge and cool to obtain a pre-plasticized material.

[0022] Step 3: Add the hybrid flame retardant masterbatch prepared in step 1, the preplasticized material prepared in step 2, thermoplastic polyurethane elastomer, ethylene-octene copolymer, zinc oxide, stearic acid, sulfur, accelerator, antioxidant, carbon black, tri(2-carboxyethyl)phosphine and paraffin oil to an internal mixer in sequence for mixing, the internal mixer speed is 40-50rpm, and dynamically vulcanize at 170-175°C for 3-4min, then pass through a twin-screw extruder with a screw speed of 50-70rpm, dynamically vulcanize at 170-175°C for 5-6min, granulate, cool, and obtain a covering rubber material.

[0023] Step 4: The covering layer granules are dynamically vulcanized through two extruders and a mold and then directly bonded to the fabric integral belt core in a hot state. The speed of the extruder is 50-60 rpm, the temperature of the extruder is 160-175°C, the mold temperature is 160-175°C, and the surface temperature of the belt core is 145-165°C to obtain a dynamically vulcanized fabric integral core flame retardant conveyor belt.

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

[0025] Polyethylene paste resin, dioctyl phthalate, epoxidized soybean oil, medium-chain chlorinated paraffin, tri(2-carboxyethyl)phosphine, aluminum hydroxide, antimony trioxide and calcium zinc composite stabilizer are mixed to obtain a dipped rubber, which is then woven into an integral belt core using polyester / cotton fiber, and the integral belt core is dipped and plasticized to obtain a fabric integral belt core.

[0026] Furthermore, the rubber content of the entire fabric core is 50-60%, the plasticizing temperature is 160-170° C., and the plasticizing time is 2 min / mm.

[0027] Furthermore, the dipping formula comprises the following components in parts by mass:

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

[0029] Beneficial effects of the present invention:

[0030] (1) The dynamically vulcanized fabric whole core flame retardant conveyor belt prepared by the present invention is prepared by compounding expanded graphite, diethyl aluminum hypophosphite, melamine polyphosphate and 2-methylimidazole zinc salt, firstly surface treating the composite hybrid flame retardant material by polymerizing ionic liquid, and then modifying the surface of the metal organic framework material 2-methylimidazole zinc salt by polymerizing ionic liquid to enhance the antistatic ability of 2-methylimidazole zinc salt. The obtained covering layer rubber has excellent flame retardant and antistatic properties and mechanical properties as well as adhesion performance with the belt core.

[0031] (2) The dynamically vulcanized fabric whole core flame retardant conveyor belt prepared by the present invention improves the compatibility of the composite hybrid flame retardant masterbatch with the pre-plasticized material, 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 properties, mechanical properties, adhesion properties and processing performance of the covering layer rubber.

[0032] (3) The dynamically vulcanized fabric whole-core flame-retardant conveyor belt prepared by the present invention forms a denser carbon layer on the covering rubber material by adding 2-methylimidazole zinc salt, which promotes carbonization to isolate heat and oxygen, and effectively improves the flame retardant properties of the covering rubber material. The addition of 2-methylimidazole zinc salt can also prevent the agglomeration of the composite hybrid flame retardant material, improve the compatibility and dispersibility between the composite hybrid flame retardant material and the covering rubber material, and in addition to improving the flame retardant properties of the covering rubber material, also improves the thermal stability, electrical conductivity and mechanical properties of the covering rubber material.

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

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

[0035] (6) The manufacturing method of the present invention adopts extruder veneer molding and dynamic vulcanization technology to achieve continuous production of conveyor belts. Compared with calendering, molding, and flat plate vulcanization processes, it saves energy consumption, improves production efficiency, has a simple process, and is easy to manufacture. DETAILED DESCRIPTION

[0036] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] Embodiment 1: A dynamically vulcanized fabric integral core flame retardant conveyor belt, comprising a covering layer and a fabric integral belt core.

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

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

[0040] S1. 30 kg of expanded graphite, 30 kg of diethyl aluminum hypophosphite, 20 kg of melamine polyphosphate and 2.5 kg of 2-methylimidazole zinc salt were put into a kneader, heated to 40° C. at a speed of 350 rpm and stirred for 20 min. 1.5 kg of polymerized ionic liquid was sprayed into the kneader, and then the temperature was raised to 105° C. and stirred for 10 min. After cooling, a composite hybrid flame retardant material was obtained.

[0041] S2. Add 40 kg of composite hybrid flame retardant material into an internal mixer, heat to 70°C at 40 rpm, then add 30 kg of butadiene rubber for blending, blending time 4 min, rubber discharge temperature 140°C, sheet out, cool to room temperature, and stand for 8 h to obtain a hybrid 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 into a high-speed kneader in sequence at a mixing speed of 1200rpm, mix at a temperature of 135°C for 10min, discharge and cool to obtain a pre-plasticized material.

[0043] S4. The hybrid flame retardant masterbatch prepared by S2, the preplasticized material prepared by 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 tri(2-carboxyethyl)phosphine and 4 kg of paraffin oil are added into an internal mixer in sequence for mixing. The internal mixer speed is 40 rpm. The mixture is dynamically vulcanized at 170°C for 3 min. The mixture is then passed through a twin-screw extruder at a screw speed of 50 rpm and dynamically vulcanized at 170°C for 5 min. The mixture is granulated and cooled to obtain a covering rubber compound.

[0044] S5. 100kg of polyethylene paste resin, 50kg of dioctyl phthalate, 10kg of epoxy soybean oil, 10kg of medium-chain chlorinated paraffin, 15kg of tri(2-carboxyethyl)phosphine, 5kg of aluminum hydroxide, 5kg of antimony trioxide and 5kg of calcium-zinc composite stabilizer are mixed to obtain a dipped rubber, which is then woven into an integral belt core with polyester / cotton fiber. The integral belt core is dipped in rubber and plasticized to obtain a fabric integral belt core, wherein the glue content of the fabric integral belt core is 50%, the plasticizing temperature is 160°C, and the plasticizing time is 2 min / mm.

[0045] S6. The covering layer granules are dynamically vulcanized through two extruders and a mold and then directly bonded to the fabric integral belt core in a hot state. The speed of the extruder is 50 rpm, the temperature of the extruder is 160°C, the temperature of the mold is 160°C, and the surface temperature of the belt core is 145°C to obtain a dynamically vulcanized fabric integral core flame retardant conveyor belt.

[0046] The accelerator is prepared by mixing 2-mercaptobenzothiazole (M), 2,2'-dibenzothiazole disulfide (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] Embodiment 2: A dynamically vulcanized fabric integral core flame retardant conveyor belt, comprising a covering layer and a fabric integral belt core.

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

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

[0051] S1. 32.5 kg of expanded graphite, 32.5 kg of diethyl aluminum hypophosphite, 22.5 kg of melamine polyphosphate and 3 kg of 2-methylimidazole zinc salt were put into a kneader, heated to 50° C. at a speed of 370 rpm and stirred for 25 min. 2 kg of polymerized ionic liquid was sprayed into the kneader, and then the temperature was raised to 107° C. and stirred for 12.5 min. After cooling, a composite hybrid flame retardant material was obtained.

[0052] S2. Add 45 kg of composite hybrid flame retardant material into an internal mixer, heat to 75 ° C at a speed of 50 rpm, then add 35 kg of butadiene rubber for blending, the blending time is 4.5 min, the rubber discharge temperature is 142.5 ° C, the sheet is discharged, cooled to room temperature, and parked for 9 hours to obtain a hybrid flame retardant masterbatch.

[0053] S3. Add 35 kg of polyvinyl chloride resin, 14 kg of dioctyl phthalate, 7 kg of antimony trioxide, 3.5 kg of methyl silicone oil and 3.5 kg of calcium zinc composite stabilizer into a high-speed kneader in sequence at a mixing speed of 1300 rpm, mix at a temperature of 140°C for 12.5 min, discharge and cool to obtain a pre-plasticized material.

[0054] S4. The hybrid flame retardant masterbatch prepared by S2, the preplasticized material prepared by S3, 15kg of thermoplastic polyurethane elastomer, 15kg of ethylene-octene copolymer, 3kg of zinc oxide, 1.5kg of stearic acid, 0.8kg of sulfur, 1.75kg of accelerator, 1.75kg of antioxidant, 14kg of carbon black N234, 10kg of tri(2-carboxyethyl)phosphine and 5kg of paraffin oil are added into an internal mixer in sequence for mixing. The speed of the internal mixer is 45rpm. The mixture is dynamically vulcanized at 173°C for 3.5min. The mixture is then passed through a twin-screw extruder at a screw speed of 60rpm and dynamically vulcanized at 173°C for 5.5min. The mixture is granulated and cooled to obtain a covering rubber compound.

[0055] S5. 110kg of polyethylene paste resin, 55kg of dioctyl phthalate, 12.5kg of epoxidized soybean oil, 15kg of medium-chain chlorinated paraffin, 20kg of tri(2-carboxyethyl)phosphine, 7.5kg of aluminum hydroxide, 5.5kg of antimony trioxide and 5.5kg of calcium-zinc composite stabilizer are mixed to obtain a dipped rubber, which is then woven into an integral belt core with polyester / cotton fiber. The integral belt core is dipped in rubber and plasticized to obtain a fabric integral belt core, wherein the fabric integral belt core has a rubber content of 55%, a plasticizing temperature of 165°C, and a plasticizing time of 2 min / mm.

[0056] S6. The covering layer granules are dynamically vulcanized through two extruders and a mold and then directly bonded to the fabric integral belt core in a hot state. The speed of the extruder is 55 rpm, the temperature of the extruder is 170°C, the temperature of the mold is 170°C, and the surface temperature of the belt core is 150°C to obtain a dynamically vulcanized fabric integral core flame retardant conveyor belt.

[0057] The accelerator is prepared by mixing 2-mercaptobenzothiazole (M), 2,2'-dibenzothiazole disulfide (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] Embodiment 3: A dynamically vulcanized fabric integral core flame retardant conveyor belt, comprising a covering layer and a fabric integral belt core.

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

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

[0062] S1. 35 kg of expanded graphite, 35 kg of diethyl aluminum hypophosphite, 25 kg of melamine polyphosphate and 3.5 kg of 2-methylimidazole zinc salt were put into a kneader, heated to 60° C. at a speed of 400 rpm and stirred for 30 min. 2.5 kg of polymerized ionic liquid was sprayed into the kneader, and then the temperature was raised to 110° C. and stirred for 15 min. After cooling, a composite hybrid flame retardant material was obtained.

[0063] S2. Add 50 kg of composite hybrid flame retardant material into an internal mixer, heat to 80 ° C at a speed of 60 rpm, then add 40 kg of butadiene rubber for blending, blending time 5 min, rubber discharge temperature 145 ° C, sheet out, cool to room temperature, and park for 10 hours to obtain a hybrid flame retardant masterbatch.

[0064] S3. Add 40kg of polyvinyl chloride resin, 16kg of dioctyl phthalate, 8kg of antimony trioxide, 5kg of sodium chloride and 5kg of calcium-zinc composite stabilizer into a high-speed kneader in sequence at a mixing speed of 1400rpm, mix at a temperature of 145°C for 15min, discharge and cool to obtain a pre-plasticized material.

[0065] S4. The hybrid flame retardant masterbatch prepared by S2, the preplasticized material prepared by S3, 20kg of thermoplastic polyurethane elastomer, 20kg of ethylene-octene copolymer, 4kg of zinc oxide, 2kg of stearic acid, 1kg of sulfur, 2kg of accelerator, 2kg of antioxidant, 16kg of carbon black N330, 12kg of tri(2-carboxyethyl)phosphine and 6kg of paraffin oil are sequentially added into an internal mixer for mixing at a speed of 50rpm. The mixture is dynamically vulcanized at 175°C for 4min. The mixture is then passed through a twin-screw extruder at a screw speed of 70rpm and dynamically vulcanized at 175°C for 6min. The mixture is granulated and cooled to obtain a covering rubber compound.

[0066] S5. 120kg of polyethylene paste resin, 60kg of dioctyl phthalate, 15kg of epoxidized soybean oil, 20kg of medium-chain chlorinated paraffin, 25kg of tri(2-carboxyethyl)phosphine, 10kg of aluminum hydroxide, 6kg of antimony trioxide and 6kg of calcium-zinc composite stabilizer are mixed to obtain a dipped rubber, which is then woven into an integral belt core with polyester / cotton fiber. The integral belt core is dipped in rubber and plasticized to obtain a fabric integral belt core, wherein the fabric integral belt core has a rubber content of 60%, a plasticizing temperature of 170°C, and a plasticizing time of 2 min / mm.

[0067] S6. The covering layer granules are dynamically vulcanized through two extruders and a mold and then directly bonded to the fabric integral belt core in a hot state. The speed of the extruder is 60 rpm, the temperature of the extruder is 175°C, the temperature of the mold is 175°C, and the surface temperature of the belt core is 165°C to obtain a dynamically vulcanized fabric integral core flame retardant conveyor belt.

[0068] The accelerator is prepared by mixing 2-mercaptobenzothiazole (M), 2,2'-dibenzothiazole disulfide (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 to S1.

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

[0072] Comparative Example 3: The difference from Example 1 is that no ethylene-octene copolymer is added to S4.

[0073] The performance tests of the cover rubber materials prepared in Examples 1 to 3 and Comparative Examples 1 to 3 were carried out. The tensile strength, elongation at break, abrasion, adhesion strength between the cover layer and the belt core, surface resistance and alcohol burner burning test of the test samples were tested according to the standard MT / T 914-2019. The results are shown in Table 1:

[0074]

[0075] It can be seen from Table 1 that the covering layer rubber material of the dynamically vulcanized fabric whole 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 property, short flame / flameless burning time, fast extinguishing, good flame retardant ability, and high bonding strength with the fabric whole belt core, all of which meet the requirements of standard MT / T914-2019.

[0076] Since no polymerized ionic liquid is added to Comparative Example 1, the surface of the composite flame retardant is not modified and the dispersibility is poor, so the antistatic property, flame retardancy and mechanical properties of Comparative Example 1 are very low.

[0077] Since no 2-methylimidazole zinc salt was added to Comparative Example 2, the antistatic performance of the cover rubber material was slightly improved, the synergistic effect with the flame retardant was lost, and the flame retardant ability was poor.

[0078] In Comparative Example 3, since no ethylene-octene copolymer was added, the compatibility of the composite hybrid flame retardant masterbatch with the pre-plasticized material, thermoplastic polyurethane elastomer and other additives was poor, resulting in reduced performance of the covering layer rubber.

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

Claims

1. A dynamically vulcanized fabric whole core flame retardant conveyor belt, characterized in that: It includes a covering layer and a fabric integral belt core; The covering layer comprises the following components in parts by mass: 30-40 parts of polyvinyl chloride resin, 30-40 parts of butadiene rubber, 10-20 parts of thermoplastic polyurethane elastomer, 10-20 parts of ethylene-octene copolymer, 2-4 parts of zinc oxide, 1-2 parts of stearic acid, 0.6-1 parts of sulfur, 1.5-2 parts of accelerator, 1.5-2 parts of antioxidant, 12-16 parts of carbon black, 6-8 parts of antimony trioxide, 40-50 parts of composite hybrid flame retardant material, 12-16 parts of dioctyl phthalate, 8-12 parts of tri(2-carboxyethyl)phosphine, 4-6 parts of paraffin oil, 2-5 parts of antistatic agent and 2-5 parts of calcium zinc composite stabilizer; The fabric integral belt core is made by plasticizing the integral belt core through dipping in glue.

2. A dynamically vulcanized fabric solid core flame retardant conveyor belt according to claim 1, characterized in that: The composite hybrid flame retardant material is prepared by the following steps: Expanded graphite, diethyl aluminum hypophosphite, melamine polyphosphate and 2-methylimidazole zinc salt are put into a kneader, heated to 40-60° C. at a rotation speed of 350-400 rpm and stirred for 20-30 minutes, and after spraying polymerized ionic liquid into the kneader, the temperature is raised to 105-110° C. and stirred for 10-15 minutes, and a composite hybrid flame retardant material is obtained after cooling.

3. A dynamically vulcanized fabric solid core flame retardant conveyor belt according to claim 2, characterized in that: The mass ratio of the expanded graphite, diethyl aluminum hypophosphite, melamine polyphosphate, 2-methylimidazole zinc salt and polymerized ionic liquid is 30-35:30-35:20-25:2.5-3.5:1.5-2.

5.

4. A dynamically vulcanized fabric solid core flame retardant conveyor belt according to claim 3, characterized in that: The polymeric ionic liquid is one of 1-ethyl-3-methylimidazole dimethyl phosphate, 1-ethyl-3-methylimidazole diethyl phosphate, and 1-butyl-3-methylimidazole dibutyl phosphate.

5. The dynamically vulcanized fabric solid core flame retardant conveyor belt according to claim 1, characterized in that: The accelerator is prepared by mixing 2-mercaptobenzothiazole, 2,2'-dibenzothiazole disulfide and tetramethylthiuram disulfide in a mass ratio of 5-6:7-8.

6. The dynamically vulcanized fabric 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.

7. The method for manufacturing a dynamically vulcanized fabric solid core flame retardant conveyor belt according to claim 1, characterized in that: The steps include: Step 1, adding the composite hybrid flame retardant material into an internal mixer, heating to 70-80°C at a speed of 40-60rpm, then adding butadiene rubber and blending for 4-5min, the discharge temperature is 140-145°C, discharging the sheet, cooling to room temperature, and parking for 8-10h to obtain a hybrid flame retardant masterbatch; Step 2, adding polyvinyl chloride resin, dioctyl phthalate, antimony trioxide, antistatic agent and calcium zinc composite stabilizer into a high-speed kneader in sequence, with a mixing speed of 1200-1400 rpm, mixing at a temperature of 135-145° C. for 10-15 minutes, discharging and cooling to obtain a pre-plasticized material; Step 3, adding the hybrid flame retardant masterbatch prepared in step 1, the preplasticized material prepared in step 2, thermoplastic polyurethane elastomer, ethylene-octene copolymer, zinc oxide, stearic acid, sulfur, accelerator, antioxidant, carbon black, tri(2-carboxyethyl)phosphine and paraffin oil to an internal mixer in sequence for mixing, the internal mixer speed is 40-50rpm, and dynamically vulcanized at 170-175°C for 3-4min, and then passed through a twin-screw extruder with a screw speed of 50-70rpm, dynamically vulcanized at 170-175°C for 5-6min, granulated, cooled, and obtained a covering rubber material; Step 4: The covering layer granules are dynamically vulcanized through two extruders and a mold and then directly bonded to the fabric integral belt core in a hot state. The speed of the extruder is 50-60 rpm, the temperature of the extruder is 160-175°C, the mold temperature is 160-175°C, and the surface temperature of the belt core is 145-165°C to obtain a dynamically vulcanized fabric integral core flame retardant conveyor belt.

8. The method for manufacturing a dynamically vulcanized fabric solid core flame retardant conveyor belt according to claim 7, characterized in that: The fabric integral belt core is prepared by the following steps: Polyethylene paste resin, dioctyl phthalate, epoxidized soybean oil, medium-chain chlorinated paraffin, tri(2-carboxyethyl)phosphine, aluminum hydroxide, antimony trioxide and calcium zinc composite stabilizer are mixed to obtain a dipped rubber, which is then woven into an integral belt core using polyester / cotton fiber, and the integral belt core is dipped and plasticized to obtain a fabric integral belt core.

9. The method for manufacturing a dynamically vulcanized fabric solid core flame retardant conveyor belt according to claim 8, characterized in that: The rubber content of the fabric core is 50-60%, the plasticizing temperature is 160-170° C., and the plasticizing time is 2 min / mm.

10. The method for manufacturing a dynamically vulcanized fabric solid core flame retardant conveyor belt according to claim 8, characterized in that: The dipping formula comprises the following components in parts by mass: 100-120 parts of polyethylene paste resin, 50-60 parts of dioctyl phthalate, 10-15 parts of epoxidized soybean oil, 10-20 parts of medium-chain chlorinated paraffin, 15-25 parts of tri(2-carboxyethyl)phosphine, 5-10 parts of aluminum hydroxide, 5-6 parts of antimony trioxide and 5-6 parts of calcium zinc composite stabilizer.

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