Wear-resistant ozawawhite gill box conveyor belt and manufacturing method thereof

Abstract

The present application relates to the technical field of conveying material, and discloses a wear-resistant Aozawa spinning frame conveying belt and a manufacturing method thereof. The present application uses aramid fiber cloth immersed by mixed emulsion of epoxy resin and blocked isocyanate solution as a skeleton material; uses modified polylactic acid, butyronitrile rubber, ethylene-vinyl alcohol copolymer and triallyl isocyanurate crosslinking material as an adhesive. Bacterial cellulose grafted with polylactic acid quaternary ammonium salt is used as a wear-resistant layer additive. The present application has the following beneficial effects: the surface of aramid fiber cloth is pretreated to introduce epoxy groups, thereby improving the adhesion between the aramid fiber cloth and rubber material; the modified polylactic acid is melt blended with ethylene-vinyl alcohol copolymer and triallyl isocyanurate, so that the polylactic acid molecular chain is crosslinked, thereby improving the heat resistance; the bacterial cellulose grafted with polylactic acid quaternary ammonium salt is introduced into the wear-resistant layer as an additive, thereby improving the wear resistance of the conveying belt.

Description

Technical Field

[0001] This invention relates to the field of conveying materials technology, specifically to a wear-resistant conveyor belt for a Qingze spinning machine and its manufacturing method. Background Technology

[0002] Currently, polyethersulfone is the main skeleton material for spinning machine conveyor belts on the market. Although it has excellent chemical resistance and high-temperature resistance, it has low strength and low modulus. In comparison, aramid fiber has a strength 5-6 times greater than high-quality steel and a modulus 2-3 times greater than steel or glass fiber. It also has good chemical resistance, high-temperature resistance, and flame retardancy, making it a good skeleton material. However, due to its structure, aramid fiber has poor adhesion when compounded with rubber materials. Therefore, it is necessary to introduce an adhesive between aramid fiber and rubber to improve the composite performance of the materials.

[0003] In summary, solving the above problems and manufacturing a wear-resistant conveyor belt for Qingze spinning machines is of great significance. Summary of the Invention

[0004] The purpose of this invention is to provide a wear-resistant conveyor belt for a spinning machine and a method for manufacturing the same, so as to solve the problems mentioned in the background art.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0006] A method for manufacturing a wear-resistant conveyor belt for a spinning machine includes the following steps:

[0007] S1: Nitrile rubber, modified polylactic acid, ethylene-vinyl alcohol copolymer, and triallyl isocyanurate are mixed to obtain a premix; the premix is ​​then mixed with acetone to obtain a modified adhesive.

[0008] S2: Mix, thin, and calender the wear-resistant layer raw materials to obtain the wear-resistant layer;

[0009] S3: The aramid fiber cloth is immersed in a skeleton layer treatment solution to obtain a skeleton layer; the skeleton layer is coated with a modified adhesive on both sides to obtain an adhesive layer; the wear-resistant layer is bonded to both sides of the adhesive layer, and the wear-resistant Qingze fine yarn machine conveyor belt is obtained after irradiation and hot pressing.

[0010] The modified adhesive comprises the following raw materials in parts by weight: 6-10 parts nitrile rubber, 0.5-3 parts modified polylactic acid, 0.3-1.8 parts ethylene-vinyl alcohol copolymer, and 0.05-0.25 parts triallyl isocyanurate.

[0011] More preferably, the preparation process of the modified polylactic acid is as follows: lactic acid, β-chlorolactic acid, four-armed star-shaped polyethylene glycol, and stannous octoate are mixed evenly and stirred at 80-140℃ and 8-12kPa for 15-30 min, then heated to 150-170℃ and polymerized at a constant temperature for 8-10 h to obtain modified polylactic acid preform. The modified polylactic acid preform is dissolved in dichloromethane and precipitated with ice-cold diethyl ether to obtain modified polylactic acid.

[0012] More preferably, the modified polylactic acid comprises the following raw materials in parts by weight: 8-10 parts lactic acid, 1-5 parts β-chlorolactic acid, 10-12 parts tetra-armed star-shaped polyethylene glycol, and 1% stannous octoate by weight of the total mass of lactic acid and β-chlorolactic acid.

[0013] The wear-resistant layer comprises the following raw materials in parts by weight: 90-100 parts hydrogenated nitrile rubber, 5-15 parts silica, 5-6 parts rubber oil, 10-30 parts polylactic acid additive, 1-3 parts vulcanization accelerator and 1-2 parts sulfur.

[0014] Preferably, the rubber oil includes, but is not limited to, one of naphthenic oil, aromatic oil, and paraffinic oil; the vulcanization accelerator includes, but is not limited to, one of thiazole, thiuram, and sulfenamide.

[0015] Preferably, the polylactic acid additive is bacterial cellulose grafted with polylactic acid quaternary ammonium salt, and its preparation process is as follows: bacterial cellulose, dimethyl sulfoxide, and deionized water are mixed evenly, heated to 70°C and stirred continuously for 2 minutes, an alkaline catalyst and DL-lactide are added, and the mixture is reacted at 70-90°C under vacuum for 4-5 hours; the mixture is cooled to 40-50°C, and a dimethyl sulfoxide mixed solution of choline chloride and ferric chloride is added under a nitrogen atmosphere; the mixture is heated to 120-140°C and reacted for 2-6 hours to obtain the polylactic acid additive;

[0016] Preferably, the polylactic acid additive comprises the following raw materials in parts by weight: 0.5-2 parts bacterial cellulose, 4-6 parts dimethyl sulfoxide, 1-3 parts deionized water, 0.1-1 parts alkaline catalyst, 40-60 parts DL-lactide, 10-15 parts choline chloride, and 1-2 parts ferric chloride.

[0017] Preferably, the preparation process of the wear-resistant layer is as follows: hydrogenated nitrile rubber and silica are added to a mixer and mixed at 70-90°C for 1-3 minutes. Rubber oil, polylactic acid additive, and vulcanization accelerator are added sequentially, and the mixture is further heated and mixed. When the temperature reaches 100-130°C, the mixture is discharged from the mixer to obtain a compound. The compound is cooled to 60-90°C at room temperature, and then passed through a two-roll mill. Sulfur is added, and the mixture is passed through a two-roll mill. After standing for 16-28 hours, the mixture is warmed and then placed in a calender and calendered on nylon cloth to form a sheet with a thickness of 0.1-0.3 mm. The sheet is then wound up for later use to obtain the wear-resistant layer.

[0018] More preferably, the nylon fabric is obtained by treating with a sulfur-containing silane coupling agent. The specific steps are as follows: 1-2 parts of bis-[γ-(triethoxysilane)propyl]-tetrasulfide are mixed with 1-2 parts of acetone to obtain a prepreg solution. The nylon fabric is immersed in the prepreg solution for 20 minutes, and then dried.

[0019] The skeleton layer treatment solution comprises the following raw materials by weight: 1-3 parts epoxy resin and 0.5-2 parts 35wt% end-capped isocyanate solution. The preparation process is as follows: epoxy resin and end-capped isocyanate solution (solvent is deionized water) are sealed and stirred at 40-80℃ at a speed of 30 rpm for 10-40 min and then allowed to stand for 1 h to obtain the skeleton layer treatment solution.

[0020] Ideally, the aramid fiber cloth is immersed in the skeleton layer treatment solution for 10 to 30 minutes.

[0021] In the adhesive layer, the amount of modified adhesive applied to one side of the skeleton layer is 2-5 g / cm. 2 The absorbed dose of the irradiation process is 100-300 kGy; the temperature of the hot pressing process is controlled at 140-170℃, the pressure is controlled at 12-18 MPa, and the time is 10-30 min.

[0022] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0023] This invention uses aramid fiber cloth as the skeleton material. Aramid fiber cloth has advantages such as high strength, high heat resistance, and good wear resistance. However, due to its structure, the amide groups of aramid are difficult to interact with other atoms or groups. Furthermore, because the surface of aramid materials lacks active functional groups, the opportunity to form hydrogen bonds is limited, resulting in poor adhesion to rubber materials. In this invention, a mixed emulsion of epoxy resin and blocked isocyanate solution is used as a pretreatment liquid for the aramid fiber cloth. After the aramid fiber cloth is treated and dried, the blocked isocyanate is deblocked at high temperature and can react with the amide bonds on the aramid surface. Then, through the ring-opening reaction of epoxy resin, epoxy groups are introduced onto the surface of the aramid fiber cloth. These epoxy groups can connect with nitrile rubber through an epoxy crosslinking reaction to form a crosslinked structure, thereby improving the adhesion between the aramid fiber cloth and rubber.

[0024] This invention uses a mixture of polylactic acid (PLA) and nitrile rubber (NBR) as an adhesive. PLA possesses good biodegradability and mechanical properties, but it is not heat-resistant and is brittle. Introducing four-armed star-shaped polyethylene glycol (PEG) into the copolymerization process with PLA can extend the chain of PLA, thereby improving its toughness. By introducing ethylene-vinyl alcohol copolymer, triallyl isocyanurate, and modified PLA for melt blending, the PLA molecular chains undergo a certain degree of cross-linking after irradiation. The mobility of cross-linked PLA molecules is restricted by the cross-linking points, requiring more energy to break free, thus improving the heat resistance of PLA. On the other hand, NBR has strong polarity and generally poor compatibility with other polymers. Traditional PLA, limited by its weak polarity, has poor compatibility with NBR in adhesives, which affects the overall mechanical strength of the product. Therefore, this invention introduces β-chlorolactic acid during the polymerization of lactic acid, which can enhance the polarity of PLA and improve its compatibility with NBR in adhesives.

[0025] Furthermore, this invention introduces a polylactic acid (PLA) additive into the wear-resistant layer. The PLA additive is bacterial cellulose grafted with PLA quaternary ammonium salt. Bacterial cellulose possesses excellent strength and stiffness, as well as good heat and chemical resistance. Adding it to rubber as an additive increases the rubber's strength and hardness, and its stability under high temperatures or chemical environments, thereby improving its wear resistance. Simultaneously, it reduces the amount of silica used, resulting in stronger adhesion between the wear-resistant layer material and the adhesive layer. On the other hand, the introduction of PLA quaternary ammonium salt acts as an antistatic agent in the wear-resistant layer. It improves the conductivity of the rubber surface, reduces static electricity buildup, helps prevent dust and other particles from adhering to the rubber product, reduces the risk of electrostatic discharge, increases the smoothness of the product surface, and lowers its coefficient of friction, thus achieving the goal of improving the wear resistance of the conveyor belt. Detailed Implementation

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below. 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 skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] The following examples contain the following raw materials: lactic acid (CAS No.: 50-21-5); β-chlorolactic acid (CAS No.: 1713-85-5); tetra-armed star-shaped polyethylene glycol (MW5000), manufactured by Shanghai Maclean Biochemical Technology Co., Ltd.; stannous octoate (CAS No.: 301-10-0); dichloromethane (CAS No.: 75-09-2); glacial ether (CAS No.: 60-29-7); nitrile rubber (NBR3305), manufactured by Lanzhou Petrochemical; ethylene-vinyl alcohol copolymer (E171), manufactured by Kuraray. Co., Ltd.; CAS No. of triallyl isocyanurate: 1025-15-6; CAS No. of acetone: 67-64-1; Bacterial cellulose, manufacturer: Tianjin Xidian Chemical Technology Co., Ltd.; CAS No. of dimethyl sulfoxide: 67-68-5; CAS No. of triethylamine: 121-44-8; CAS No. of DL-lactide: 95-96-5; CAS No. of choline chloride: 67-48-1; CAS No. of ferric chloride: 7705-08-0; CAS No. of bis-[γ-(triethoxysilyl)propyl]tetrasulfide: 40372-72-3; Nylon fabric, manufacturer: Dongguan Panglai Environmental Protection Technology Co., Ltd.; Hydrogenated nitrile butadiene rubber, grade: 2010, Manufacturer: Ruiweng; CAS No. of precipitated silica: 10279-57-9; Naphthenic rubber oil, Manufacturer: Shanghai Hongzhuang Chemical Technology Co., Ltd.; CAS No. of accelerator TMTD: 137-26-8; CAS No. of sulfur: 7704-34-9; Epoxy resin, Manufacturer: Shandong Jinyu Chemical Co., Ltd.; End-capped isocyanate, Manufacturer: Wuhan Xinxin Jiali Biotechnology Co., Ltd.; Aramid, thickness 0.45mm, basis weight 210g / m² 2 Manufacturer: Zhongfang Special Fiber Co., Ltd.

[0028] Example 1: S1: (1) Mix 9 parts of lactic acid, 2 parts of β-chlorolactic acid, 11 parts of four-arm star-shaped polyethylene glycol, and 0.11 parts of stannous octoate evenly, stir and react for 20 min at 120℃ and 10 kPa, then heat and polymerize at a heating rate of 5℃ / min. After the temperature reaches 165℃, maintain the temperature and polymerize for 9 h to obtain modified polylactic acid preform. Dissolve the modified polylactic acid preform in dichloromethane and precipitate it with ice-cold ether to obtain modified polylactic acid; (2) Add 8 parts of nitrile rubber, 1 part of modified polylactic acid, 0.6 parts of ethylene-vinyl alcohol copolymer, and 0.08 parts of triallyl isocyanurate to a mixer and mix at 80℃ for 10 min to obtain a premix; mix 1 part of the premix and 3 parts of acetone evenly at 55℃ to obtain a modified adhesive;

[0029] S2: (1) Mix 1 part bacterial cellulose, 5 parts dimethyl sulfoxide, and 2 parts deionized water evenly, heat to 70°C and stir continuously for 2 minutes, then add 0.2 parts triethylamine and 50 parts DL-lactide in sequence, and react at 80°C for 4 hours under vacuum; cool to 40°C, and under nitrogen atmosphere, add a mixed solution of 14 parts choline chloride and 1.6 parts ferric chloride in dimethyl sulfoxide; heat to 130°C and react for 4 hours to obtain polylactic acid additive; (2) Mix 1 part bis-[γ-(triethoxysilyl)propyl]-tetrasulfide and 1 part acetone evenly to obtain a prepreg solution, immerse nylon fabric in the prepreg solution for 20 minutes, and take... After drying, it is ready for use; (3) Add 100 parts of hydrogenated nitrile rubber and 5 parts of silica to the internal mixer and mix at 80°C for 2 minutes. Then add 6 parts of naphthenic rubber oil, 30 parts of polylactic acid additive and 2 parts of accelerator TMTD. Continue to heat and mix. When the temperature reaches 120°C, discharge the internal mixer to obtain the compound; cool the compound to 80°C at room temperature, put the compound into the open mill for thin-passing, add 2 parts of sulfur, and put the compound into the open mill for 24 hours. After warming the compound, place it in the calender and calender it on the nylon cloth to form a sheet with a thickness of 0.2 mm. Roll it up for use to obtain the wear-resistant layer;

[0030] S3: (1) Mix 2 parts epoxy resin with 1 part 35wt% end-capped isocyanate solution (solvent is deionized water) at 60℃ with a sealed stirring speed of 30 rpm for 30 min, and let stand for 1 h to obtain the skeleton layer treatment solution; (2) Immerse aramid fiber cloth in the skeleton layer treatment solution for 20 min, dry it to obtain the skeleton layer, and then add the modified adhesive at 3g / cm 2 The coating amount is applied to both sides of the skeleton layer, dried in an oven to obtain the adhesive layer, and the wear-resistant layer material is attached to both sides of the adhesive layer. After being irradiated with 200 kGy of γ-rays, it is hot-pressed at 155℃ and 15MPa for 25 minutes to obtain the wear-resistant Qingze fine yarn machine conveyor belt.

[0031] Example 2: S1: (1) Mix 10 parts of lactic acid, 5 parts of β-chlorolactic acid, 12 parts of four-arm star-shaped polyethylene glycol, and 0.15 parts of stannous octoate evenly, stir and react for 20 min at 120℃ and 10 kPa, then heat and polymerize at a heating rate of 5℃ / min. After the temperature reaches 165℃, maintain the temperature for 9 h to obtain modified polylactic acid preform. Dissolve the modified polylactic acid preform in dichloromethane and precipitate it with ice-cold ether to obtain modified polylactic acid; (2) Add 8 parts of nitrile rubber, 1 part of modified polylactic acid, 0.6 parts of ethylene-vinyl alcohol copolymer, and 0.08 parts of triallyl isocyanurate to a mixer and mix at 80℃ for 10 min. Discharge the premix to obtain a premix; mix 1 part of the premix and 3 parts of acetone evenly at 55℃ to obtain a modified adhesive;

[0032] S2: (1) Mix 1 part bacterial cellulose, 5 parts dimethyl sulfoxide and 2 parts deionized water evenly, heat to 70°C and stir continuously for 2 min, add 0.16 parts triethylamine and 40 parts DL-lactide in sequence, react at 80°C for 4 hours under vacuum; cool to 40°C, add 14 parts choline chloride and 1.6 parts ferric chloride in a dimethyl sulfoxide mixed solution under nitrogen atmosphere; heat to 130°C and react for 4 h to obtain polylactic acid additive; (2) Mix 1 part bis-[γ-(triethoxysilyl)propyl]-tetrasulfide and 1 part acetone evenly to obtain prepreg solution, immerse nylon fabric in the prepreg solution for 20 min, take it out and dry it for later use;

[0033] (3) Add 100 parts of hydrogenated nitrile rubber and 10 parts of silica to a mixer and mix at 80°C for 2 minutes. Then add 6 parts of naphthenic rubber oil, 20 parts of polylactic acid additive, and 2 parts of accelerator TMTD. Continue to heat and mix. When the temperature reaches 120°C, discharge the mixture from the mixer to obtain the compound. Cool the compound to 80°C at room temperature. Place the compound in a two-roll mill for thin-passing. Add 2 parts of sulfur and place the mixture in the two-roll mill. After standing for 24 hours, warm the mixture and then place it in a calender. Calender the mixture on nylon cloth to form a sheet with a thickness of 0.2 mm. Roll it up for later use to obtain the wear-resistant layer.

[0034] S3: (1) Mix 2 parts of epoxy resin and 1 part of 35wt% end-capped isocyanate solution (solvent is deionized water) at 60°C with a sealed stirring speed of 30 rpm. After mixing for 30 min, let stand for 1 h to obtain the skeleton layer treatment solution; (2) Immerse aramid fiber cloth in the skeleton layer treatment solution for 20 min, dry it to obtain the skeleton layer, then coat the modified adhesive on both sides of the skeleton layer with a coating amount of 3 g / cm2, dry it in an oven to obtain the adhesive layer, attach the wear-resistant layer material to both sides of the adhesive layer, irradiate with 200 kGy of γ-rays, and hot press it at 155°C and 15 MPa for 25 min to obtain the wear-resistant Qingze fine yarn machine conveyor belt.

[0035] Example 3: S1: (1) Mix 9 parts of lactic acid, 2 parts of β-chlorolactic acid, 11 parts of four-arm star-shaped polyethylene glycol, and 0.11 parts of stannous octoate evenly, stir and react for 20 min at 120℃ and 10 kPa, then heat and polymerize at a heating rate of 5℃ / min. After the temperature reaches 165℃, maintain the temperature for 9 h to obtain modified polylactic acid preform. Dissolve the modified polylactic acid preform in dichloromethane and precipitate it with ice-cold ether to obtain modified polylactic acid; (2) Add 8 parts of nitrile rubber, 1 part of modified polylactic acid, 0.6 parts of ethylene-vinyl alcohol copolymer, and 0.08 parts of triallyl isocyanurate to a mixer and mix at 80℃ for 10 min. Discharge the premix to obtain a premix; mix 1 part of the premix and 3 parts of acetone evenly at 55℃ to obtain a modified adhesive;

[0036] S2: (1) Mix 2 parts bacterial cellulose, 6 parts dimethyl sulfoxide and 3 parts deionized water evenly, heat to 70°C and stir continuously for 2 min, add 0.24 parts triethylamine and 60 parts DL-lactide in sequence, react at 80°C for 5 hours under vacuum; cool down to 40°C, add 14 parts choline chloride and 1.6 parts ferric chloride in a dimethyl sulfoxide mixed solution under nitrogen atmosphere; heat up to 130°C and react for 4 h to obtain polylactic acid additive; (2) Mix 1 part bis-[γ-(triethoxysilyl)propyl]-tetrasulfide and 1 part acetone evenly to obtain prepreg solution, immerse nylon fabric in the prepreg solution for 20 min, take it out and dry it for later use;

[0037] (3) Add 90 parts of hydrogenated nitrile rubber and 15 parts of silica to a mixer and mix at 80°C for 2 minutes. Then add 6 parts of naphthenic rubber oil, 10 parts of polylactic acid additive and 2 parts of accelerator TMTD. Continue to heat and mix. When the temperature reaches 120°C, discharge the mixture from the mixer to obtain the compound. Cool the compound to 80°C at room temperature. Place the compound in a two-roll mill for thin-passing. Add 2 parts of sulfur and place the mixture in the two-roll mill. After standing for 24 hours, warm the mixture and then place it in a calender. Calender the mixture on nylon cloth to form a sheet with a thickness of 0.2 mm. Roll it up for later use to obtain the wear-resistant layer.

[0038] S3: (1) Mix 2 parts of epoxy resin and 1 part of 35wt% end-capped isocyanate solution (solvent is deionized water) at 60°C with a sealed stirring speed of 30 rpm. After mixing for 30 min, let stand for 1 h to obtain the skeleton layer treatment solution; (2) Immerse aramid fiber cloth in the skeleton layer treatment solution for 20 min, dry it to obtain the skeleton layer, then coat the modified adhesive on both sides of the skeleton layer with a coating amount of 3 g / cm2, dry it in an oven to obtain the adhesive layer, attach the wear-resistant layer material to both sides of the adhesive layer, irradiate with 200 kGy of γ-rays, and hot press it at 155°C and 15 MPa for 25 min to obtain the wear-resistant Qingze fine yarn machine conveyor belt.

[0039] Comparative Example 1: Compared with Example 1, Comparative Example 1 removed ethylene-vinyl alcohol copolymer and triallyl isocyanurate from the modified adhesive raw materials, while the rest of the process remained unchanged.

[0040] Comparative Example 2: Compared with Example 1, Comparative Example 2 removed β-chlorolactic acid from the modified polylactic acid, while the rest of the process remained unchanged.

[0041] Comparative Example 3: Compared with Example 1, Comparative Example 3 removed the end-capped isocyanate solution from the skeleton layer treatment solution, while the rest of the process remained unchanged.

[0042] Comparative Example 4: Compared with Example 1, Comparative Example 4 replaced the bacterial cellulose grafted polylactic acid quaternary ammonium salt additive with a polylactic acid quaternary ammonium salt additive, while keeping the rest of the process unchanged. The preparation process of the polylactic acid quaternary ammonium salt is as follows: 14 parts of choline chloride, 44 parts of DL-lactide, and 1.6 parts of ferric chloride are mixed evenly, stirred and heated to 130°C under nitrogen protection, and reacted for 4 hours to obtain the polylactic acid quaternary ammonium salt additive.

[0043] Test Experiment 1: The finished conveyor belts from Examples 1-3 and Comparative Examples 1-4 were tested for abrasion resistance according to GB / T 9867-2008 and for adhesive strength according to GB / T 20021-2017. The test data are shown in Table 1.

[0044] <![CDATA[Relative volume wear (mm 3 )]]> 50 52 54 51 56 52 70 Bond strength (N / mm) 5.4 5.1 5.3 5.1 2.4 3.2 4.8

[0045] Table 1

[0046] Test Experiment 2: Examples 1, Comparative Example 1, and Comparative Example 4 were placed in an oven and heated to 160°C for 4 hours. After cooling, they were removed and tested for abrasion resistance and adhesive strength. The test data are shown in Table 2.

[0047] <![CDATA[Relative volume wear (mm 3 )]]> 53 57 82 Bond strength (N / mm) 5.1 2.3 4.1

[0048] Table 2

[0049] Conclusion: Data from Examples 1-3 show that using modified adhesives and pretreating aramid fibers can improve the bonding strength of the conveyor belt. Furthermore, introducing polylactic acid (PLA) additives into the wear-resistant layer can improve its wear resistance. Considering both aspects, Example 1 shows the best performance. A comparison of data from Example 1 and Comparative Example 1 shows that adhesives without ethylene-vinyl alcohol copolymer and triallyl isocyanurate co-crosslinking have poor high-temperature resistance. This is because PLA itself has a low glass transition temperature and is significantly affected by heat. Introducing ethylene-vinyl alcohol copolymer and triallyl isocyanurate crosslinking modification can reduce the mobility of molecular chains, thereby improving the heat resistance of PLA. A comparison of data from Example 1 and Comparative Example 2 shows that introducing chlorinated lactic acid into the modified PLA can improve the bonding strength of the conveyor belt. This is because nitrile rubber, as a high-polarity rubber, has better compatibility with high-polarity polymers. Therefore, chlorinated PLA can be better mixed with nitrile rubber in the adhesive, thereby improving the adhesion effect of the modified adhesive. A comparison of data from Example 1 and Comparative Example 3 shows that... Using epoxy resin as the pretreatment liquid for aramid materials alone results in poor overall strength of the conveyor belt. This is because aramid, as a highly crystalline polymer, has a weak ability to form hydrogen bonds due to the steric hindrance effect of the benzene ring. Simply immersing it in epoxy resin cannot form enough epoxy groups on the aramid surface, thus leading to poor overall strength. A comparison of data from Example 1 and Comparative Example 4 shows that the conveyor belt without using polylactic acid quaternary ammonium salt grafted with bacterial cellulose as an additive for the wear-resistant layer has poor overall wear resistance. This is because bacterial cellulose has good strength and stiffness. With the same amount of silica, adding bacterial cellulose can ensure that the rubber still has good strength and hardness. On the other hand, bacterial cellulose has higher stability at high temperatures, thus ensuring that the wear-resistant layer still has good wear resistance at high temperatures.

[0050] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for manufacturing a wear-resistant conveyor belt for a fine spinning machine, characterized in that, Includes the following steps: S1: Nitrile rubber, modified polylactic acid, ethylene-vinyl alcohol copolymer, and triallyl isocyanurate are mixed to obtain a premix; the premix is ​​then mixed with acetone to obtain a modified adhesive. S2: Mix the wear-resistant layer raw materials, thinly pass through, and calender to obtain the wear-resistant layer; S3: The aramid fiber cloth is immersed in a skeleton layer treatment solution to obtain a skeleton layer; the skeleton layer is coated with a modified adhesive on both sides to obtain an adhesive layer; the wear-resistant layer is attached to both sides of the adhesive layer, and after irradiation and hot pressing, a wear-resistant Qingze fine yarn machine conveyor belt is obtained. The modified adhesive comprises the following raw materials in parts by weight: 6-10 parts nitrile rubber, 0.5-3 parts modified polylactic acid, 0.3-1.8 parts ethylene-vinyl alcohol copolymer, and 0.05-0.25 parts triallyl isocyanurate; The preparation process of the modified polylactic acid is as follows: lactic acid, β-chlorolactic acid, four-armed star-shaped polyethylene glycol, and stannous octoate are mixed evenly and stirred at 80~140℃ and 8~12kPa for 15~30min. Then, the temperature is raised to 150~170℃ and polymerized at a constant temperature for 8~10h to obtain the modified polylactic acid preform. The modified polylactic acid preform is dissolved in dichloromethane and precipitated with ice-cold diethyl ether to obtain the modified polylactic acid.

2. The method for manufacturing a wear-resistant conveyor belt for a fine spinning machine according to claim 1, characterized in that, The modified polylactic acid comprises the following raw materials in parts by weight: 8-10 parts lactic acid, 1-5 parts β-chlorolactic acid, 10-12 parts four-armed star-shaped polyethylene glycol, and 1% stannous octoate by weight of the total mass of lactic acid and β-chlorolactic acid.

3. The method for manufacturing a wear-resistant conveyor belt for a fine spinning machine according to claim 1, characterized in that, The wear-resistant layer comprises the following raw materials in parts by weight: 90-100 parts hydrogenated nitrile rubber, 5-15 parts silica, 5-6 parts rubber oil, 10-30 parts polylactic acid additive, 1-3 parts vulcanization accelerator, and 1-2 parts sulfur.

4. The method for manufacturing a wear-resistant conveyor belt for a fine spinning machine according to claim 3, characterized in that, The polylactic acid additive is a bacterial cellulose-grafted polylactic acid quaternary ammonium salt. Its preparation process is as follows: bacterial cellulose, dimethyl sulfoxide, and deionized water are mixed evenly, heated to 70°C and stirred continuously for 2 minutes, an alkaline catalyst and DL-lactide are added, and the reaction is carried out under vacuum at 70~90°C for 4~5 hours; the temperature is lowered to 40~50°C, and a mixed solution of choline chloride and ferric chloride is added under a nitrogen atmosphere. The temperature is raised to 120~140℃ and the reaction is carried out for 2~6 hours to obtain polylactic acid additive.

5. The method for manufacturing a wear-resistant conveyor belt for a fine spinning machine according to claim 4, characterized in that, The polylactic acid additive comprises the following raw materials in parts by weight: 0.5-2 parts bacterial cellulose, 4-6 parts dimethyl sulfoxide, 1-3 parts deionized water, 0.1-1 parts alkaline catalyst, 40-60 parts DL-lactide, 10-15 parts choline chloride, and 1-2 parts ferric chloride.

6. The method for manufacturing a wear-resistant conveyor belt for a fine spinning machine according to claim 1, characterized in that, The skeleton layer treatment solution comprises the following raw materials in parts by weight: 1-3 parts epoxy resin and 0.5-2 parts 35wt% end-capped isocyanate solution.

7. The method for manufacturing a wear-resistant conveyor belt for a fine spinning machine according to claim 1, characterized in that, In the adhesive layer, the amount of modified adhesive applied to one side of the skeleton layer is 2~5 g / cm. 2 The absorbed dose of the irradiation process is 100~300kGy; the temperature of the hot pressing process is controlled at 140~170℃, the pressure is controlled at 12~18MPa, and the time is 10~30min.

8. The abrasion-resistant Qingze spinning machine conveyor belt obtained by the manufacturing method of the abrasion-resistant Qingze spinning machine conveyor belt according to any one of claims 1 to 7.