High-wear-resistance high-strength conveying belt and preparation process thereof

Abstract

The application relates to the technical field of conveying belts, and particularly discloses a high-wear-resistance high-strength conveying belt and a preparation process thereof. The high-wear-resistance high-strength conveying belt comprises a covering rubber and a framework layer, and the covering rubber comprises the following raw materials in parts by weight: modified rubber 100 parts, polydopamine modified carbon black 45-55 parts, vulcanizing agent 4-5 parts, active agent 6.5-7.5 parts and anti-aging agent 1-2 parts; the modified rubber is plasma-treated rubber. The application improves the compatibility of rubber and carbon black, and further improves the tensile property and wear resistance of the prepared conveying belt.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of conveying belt, more particularly, it relates to a high wear-resistant and high-strength conveying belt and a preparation process thereof. BACKGROUND

[0002] In the modern industrial system, conveying belt as the core equipment of continuous material transportation is widely used in heavy industrial fields such as coal, mine, metallurgy, port and building material. These scenes are often accompanied by extremely complex working conditions: there are not only continuous friction and impact in the process of material transportation, but also multiple environmental pressures such as high temperature, humidity and corrosive medium. Taking the mine industry as an example, the conveying belt needs to bear the long-term crushing of a large number of sharp ores, and the daily running mileage of a single conveying belt can reach hundreds of kilometers, and the annual cumulative running mileage exceeds 100,000 kilometers. In the port bulk transportation, the conveying belt needs to resist the sea salt mist corrosion and the diurnal temperature difference change, and at the same time, it needs to withstand the instantaneous impact of ten-thousand-ton material. The traditional conveying belt is limited by the material performance and the preparation process, and it is difficult to meet the above harsh requirements. The early rubber conveying belt mostly uses natural rubber single matrix, which has a certain elasticity, but the wear resistance is insufficient, and the wear amount is generally 50mm 3 Above, it needs to be replaced in 1-3 months under high load working condition; with the expansion of industrial production scale and the intelligent upgrading, the market puts forward higher requirements on the performance of the conveying belt: on the one hand, it needs to have excellent wear resistance to prolong the replacement cycle and reduce the operation and maintenance cost; on the other hand, it needs to have excellent high-strength characteristics to adapt to large-span and high-load transportation scenes and reduce the risk of fracture. Under this background, the research and development of new conveying belt with high wear resistance and high strength become the key breakthrough to solve the efficiency bottleneck of industrial transportation and reduce the comprehensive operation cost, and also become an important direction to promote the upgrading of material transportation equipment.

[0003] The patent application file with publication number CN104311896A discloses a high-strength and high-wear-resistant H-shaped covering rubber for steel cord core conveying belt, which is prepared from the following components in parts by weight: natural rubber 50-60 parts, butadiene rubber BR9000 40-50 parts, carbon black 50-60 parts, vulcanization activator 4-7 parts, aromatic oil 4-8 parts, carbon five resin 2-4 parts, protective wax 2 parts, antioxidant 1-3 parts, oil-extended insoluble sulfur 1.3-2.5 parts, vulcanization accelerator 1-2.5 parts, and anti-scorching agent CTP 0.1-0.3 parts. The method improves the tensile strength and wear resistance of the conveying belt by optimizing the formula system of the H-shaped covering rubber, and simultaneously improves the reinforcing effect by adding carbon black, but due to the poor compatibility between the rubber matrix and the carbon black, the carbon black is not uniformly dispersed to form stress concentration points, the interface bonding force is weak so that the stress cannot be effectively transmitted, and the adsorption force of the carbon black to the rubber molecules is weak, so the rubber molecular chain is easy to slide on the surface of the carbon black during stretching, and finally the tensile strength of the prepared conveying belt is not high, and the belt body is easy to tear and delaminate in high-strength transportation. SUMMARY

[0004] In order to improve the tensile strength of the prepared conveyor belt, the application provides a high wear-resistant high-strength conveyor belt and a preparation process thereof.

[0005] In a first aspect, the application provides a high wear-resistant high-strength conveyor belt, which adopts the following technical scheme:

[0006] A high wear-resistant high-strength conveyor belt, comprising a cover rubber and a framework layer, wherein the cover rubber comprises the following raw materials in parts by weight: 100 parts of modified rubber, 45-55 parts of polydopamine modified carbon black, 4-5 parts of vulcanizing agent, 6.5-7.5 parts of active agent, and 1-2 parts of anti-aging agent; the modified rubber is a plasma-treated rubber.

[0007] By adopting the above technical scheme, the plasma-treated rubber is bonded with the polydopamine modified carbon black, the micro-nano morphology of the surface of the modified carbon black and the rough structure of the surface of the rubber form physical anchoring, the plasma treatment improves the surface energy of the rubber, the polydopamine modification reduces the interfacial energy difference between the carbon black and the rubber, the carbon black is more uniformly dispersed in the rubber matrix, and the compatibility between the rubber and the carbon black is improved through the synergistic effect of chemical combination, physical embedding and dispersion optimization, thereby improving the tensile properties and wear resistance of the prepared conveyor belt.

[0008] Preferably, the preparation process of the modified rubber is as follows: the rubber is placed in a plasma device, a gas is introduced, the pressure in the chamber is maintained at 40-60 Pa, the power is set to 80-100 W, and the treatment time is 40-80 s.

[0009] By adopting the above technical scheme, the surface of the rubber is modified by plasma, the surface molecular chain is broken and polar groups are introduced, the interfacial polarity of the rubber can be effectively adjusted, the compatibility with the carbon black is enhanced, and the tensile strength and wear resistance of the conveyor belt are improved; when the power is too low, it is difficult to effectively initiate the chemical reaction and etching of the surface of the rubber; and when the power is too high and the time is too long, the surface of the rubber may be excessively oxidized and the molecular chain may be severely broken, affecting the bulk properties; therefore, under the above process parameters, the surface of the rubber can form appropriate polar groups and have appropriate roughness.

[0010] Preferably, the gas is a mixture of oxygen and argon with a volume ratio of (2-4):(6-8).

[0011] By adopting the above technical scheme, oxygen can introduce polar oxygen-containing groups on the surface of the rubber to enhance the polar interaction with the carbon black; argon as an inert gas mainly plays an etching role to increase the roughness of the surface of the rubber and promote the physical anchoring effect; and the combination of the two improves the combination of the rubber and the carbon black.

[0012] Preferably, the rubber is a mixture of natural rubber and butadiene rubber in a mass ratio of (55-65):(35-45).

[0013] By adopting the above technical scheme, the natural rubber has high elasticity, high strength and good processing performance, and the butadiene rubber gives the rubber excellent wear resistance and fatigue resistance, and the combination of the two can optimize the comprehensive performance of the conveyor belt.

[0014] Preferably, the preparation process of the polydopamine modified carbon black comprises the following steps:

[0015] (1) ultrasonic dispersion of carbon black in deionized water to obtain a suspension;

[0016] (2) adding the suspension into a Tris-HCl buffer solution, adjusting the pH of the system to 8.0-8.5, adding dopamine monomer, reacting, washing and drying to obtain polydopamine modified carbon black;

[0017] The mass ratio of dopamine monomer to carbon black is 1:(2-10).

[0018] By adopting the above technical scheme, the self-oxidation and polymerization characteristics of dopamine under alkaline conditions are utilized to form a polydopamine coating on the surface of carbon black. The polydopamine contains a large number of polar groups such as catechol and amino groups, which can form hydrogen bonds, van der Waals forces or chemical adsorption with modified rubber molecules, significantly enhancing the interfacial bonding force between carbon black and rubber matrix.

[0019] Preferably, the carbon black is further subjected to oxidation treatment before being modified with polydopamine, specifically: adding carbon black into a nitric acid solution to form a mixture, heating to 60-100℃ under stirring for 2-6h, after the reaction is completed, cooling to room temperature, pouring the mixture into deionized water, stirring and then suction filtering, washing the filter cake until the pH of the filtrate is 5-7, placing the washed filter cake in a vacuum dryer at 80-100℃ for 8-12h, and grinding to obtain oxidized carbon black.

[0020] The mass-to-volume ratio of carbon black to nitric acid solution is 1:(10-20)g / mL.

[0021] By adopting the above technical scheme, the carbon black is oxidized by nitric acid oxidation method, introducing more carboxyl groups, which significantly improves the polarity of the carbon black surface. On the one hand, it provides abundant reaction sites for subsequent polydopamine modification, ensuring that the polydopamine coating can be firmly anchored on the surface of carbon black. On the other hand, the surface polarity of the carbon black after oxidation treatment combined with polydopamine modification is highly matched with the polar surface of the plasma treated rubber, greatly reducing the interfacial tension. At the same time, strong dipole interaction and electrostatic attraction can occur between the polar groups of polydopamine and the polar groups on the surface of the rubber, further enhancing the interfacial adsorption and improving the bonding of the rubber and carbon black.

[0022] Preferably, the carbon black is one of N110 carbon black, N220 carbon black, N330 carbon black, N550 carbon black, and further preferably N330 carbon black.

[0023] By adopting the above technical solution, the N330 carbon black has a suitable specific surface area and structure, which can uniformly introduce functional groups through oxidation treatment to efficiently anchor polydopamine, and can form multiple interactions with the polar groups on the surface of the rubber after plasma treatment, thereby ensuring the interface bonding strength.

[0024] Preferably, the vulcanizing agent is a mixture of sulfur and accelerator with a mass ratio of (2-3):2; and the accelerator is a mixture of accelerator NS and accelerator DM with a mass ratio of (2-3):(1-2).

[0025] By adopting the above technical solution, the activation energy of sulfur vulcanization is reduced by the accelerator, the vulcanization efficiency is improved, the time is shortened and the temperature is reduced, the damage of high temperature to rubber is reduced; at the same time, the crosslinking density and distribution are precisely controlled, the strength, wear resistance and other mechanical properties of the vulcanized rubber are enhanced, the scorching problem in the processing process can be avoided by the aftereffect of the accelerator, the by-products such as free sulfur are reduced, the blooming risk is reduced, and the aging resistance and service life of the conveyor belt are improved.

[0026] The NS accelerator has excellent aftereffect, low activity in the processing stage, ensures that premature vulcanization does not occur, ensures processing safety, and quickly takes effect during high-temperature vulcanization; the DM accelerator as a quasi-speed accelerator can prolong the vulcanization flat period and avoid performance fluctuations caused by too fast reaction in the later stage of vulcanization, and the combination of the two can optimize the crosslinking structure and balance the strength and toughness of the vulcanized rubber, so that the conveyor belt exhibits more balanced mechanical properties and durability when bearing dynamic load and friction.

[0027] Preferably, the active agent is a mixture of zinc oxide and stearic acid with a mass ratio of (8-12):(3-5).

[0028] By adopting the above technical solution, zinc oxide can react with the accelerator to generate an intermediate product with high activity, reduce the activation energy of the vulcanization reaction, accelerate the crosslinking reaction of sulfur and rubber molecules, and improve the vulcanization speed and crosslinking density; at the same time, zinc oxide can enhance the heat resistance, aging resistance and mechanical strength of the vulcanized rubber. Stearic acid acts as an activator, which can react with zinc oxide to form soluble zinc stearate, improve the dispersibility of zinc oxide in rubber, and ensure uniform activation; on the other hand, stearic acid can lubricate the rubber molecular chain, improve the processing fluidity of the rubber, and participate in the construction of the vulcanization network to assist in enhancing the adhesion between the rubber and the skeleton layer. After the two are compounded, the vulcanization activation effect is strengthened, the high strength, high wear resistance and fatigue resistance of the conveyor belt vulcanized rubber are ensured, and the processing process is optimized, so that the conveyor belt maintains stability when bearing dynamic load, friction and environmental aging for a long time.

[0029] In a second aspect, the application provides a preparation process of a high-wear-resistance high-strength conveying belt, which adopts the following technical scheme.

[0030] The preparation process of the high-wear-resistance high-strength conveying belt comprises the following steps.

[0031] The raw materials of the cover rubber are weighed according to the formula and mixed and milled to obtain a milled rubber, the milled rubber is opened and milled to obtain a rubber sheet, and the rubber sheet is extruded to obtain a rubber material;

[0032] The adhesive is uniformly coated on the surface of the steel wire rope core and then dried to obtain a skeleton layer;

[0033] The rubber material is laminated with the skeleton layer to obtain a conveying belt blank;

[0034] The conveying belt blank is vulcanized to obtain a conveying belt.

[0035] In summary, the application has the following beneficial effects:

[0036] 1. In the application, the rubber is treated by plasma and the carbon black is modified by polydopamine, the two can be combined by bonding, the micro-nano morphology of the surface of the modified carbon black and the rough structure of the surface of the rubber form physical anchoring, the surface energy of the rubber is improved by plasma treatment, the interfacial energy difference between the carbon black and the rubber is reduced by polydopamine modification, the carbon black is more uniformly dispersed in the rubber matrix, the compatibility between the rubber and the carbon black is improved through the synergistic effect of chemical combination, physical embedding and dispersion optimization, and then the tensile properties and wear resistance of the prepared conveying belt are improved.

[0037] 2. In the application, a mixed gas of oxygen and argon is used in the plasma treatment of the rubber, the oxygen can introduce polar oxygen-containing groups on the surface of the rubber to enhance the polar interaction with the carbon black, the argon acts as an inert gas and mainly plays an etching role to increase the roughness of the surface of the rubber and promote the physical anchoring effect, and the combination of the two through chemical and physical combination improves the combination of the rubber and the carbon black.

[0038] 3. In the application, the carbon black is treated by oxidation, which provides rich reaction sites for subsequent polydopamine modification, ensures that the polydopamine coating can be firmly anchored on the surface of the carbon black, and on the other hand, after the oxidation treatment combined with the polydopamine modification, the surface polarity of the carbon black is highly matched with the polar surface of the plasma-treated rubber, the interfacial tension is greatly reduced, and the compatibility between the rubber and the carbon black is further improved. DETAILED DESCRIPTION

[0039] The application will be further described in detail below in combination with examples.

[0040] The raw materials of the examples and comparative examples of the application are ordinary commercially available materials, except for special instructions.

[0041] Preparation Example 1-11 Modified rubber

[0042] Preparation Example 1

[0043] The preparation example discloses a preparation process of modified rubber, and specifically, 100g of natural rubber is placed into a plasma treatment chamber, the chamber is closed and vacuumized to 10Pa; oxygen is introduced, the pressure in the chamber is maintained at 40Pa, a radio frequency power source is turned on, the power is set to 80W, and the modified rubber is obtained after 80s of treatment.

[0044] Preparation Example 2

[0045] The preparation example discloses a preparation process of modified rubber, and specifically, 100g of natural rubber is placed into a plasma treatment chamber, the chamber is closed and vacuumized to 10Pa; oxygen is introduced, the pressure in the chamber is maintained at 50Pa, a radio frequency power source is turned on, the power is set to 90W, and the modified rubber is obtained after 60s of treatment.

[0046] Preparation Example 3

[0047] The preparation example discloses a preparation process of modified rubber, and specifically, 100g of natural rubber is placed into a plasma treatment chamber, the chamber is closed and vacuumized to 10Pa; oxygen is introduced, the pressure in the chamber is maintained at 60Pa, a radio frequency power source is turned on, the power is set to 100W, and the modified rubber is obtained after 40s of treatment.

[0048] Preparation Example 4

[0049] The preparation example discloses a preparation process of modified rubber, and specifically, 100g of natural rubber is placed into a plasma treatment chamber, the chamber is closed and vacuumized to 10Pa; oxygen is introduced, the pressure in the chamber is maintained at 50Pa, a radio frequency power source is turned on, the power is set to 90W, and the modified rubber is obtained after 60s of treatment.

[0050] Preparation Example 5

[0051] The preparation example discloses a preparation process of modified rubber, and specifically, 100g of natural rubber is placed into a plasma treatment chamber, the chamber is closed and vacuumized to 10Pa; oxygen is introduced, the pressure in the chamber is maintained at 50Pa, a radio frequency power source is turned on, the power is set to 90W, and the modified rubber is obtained after 60s of treatment.

[0052] Preparation Example 6

[0053] The preparation example discloses a preparation process of modified rubber, specifically: 60g of natural rubber and 40g of cis-butadiene rubber are uniformly mixed and then placed into a plasma treatment chamber, the chamber is closed and vacuumized to 10Pa; oxygen is introduced to maintain the pressure in the chamber at 50Pa, a radio frequency power source is turned on, the power is set to 90W, and the modified rubber is obtained after 60s of treatment.

[0054] Preparation Example 7

[0055] The preparation example discloses a preparation process of modified rubber, specifically: 65g of natural rubber and 35g of cis-butadiene rubber are uniformly mixed and then placed into a plasma treatment chamber, the chamber is closed and vacuumized to 10Pa; oxygen is introduced to maintain the pressure in the chamber at 50Pa, a radio frequency power source is turned on, the power is set to 90W, and the modified rubber is obtained after 60s of treatment.

[0056] Preparation Example 8

[0057] The preparation example discloses a preparation process of modified rubber, specifically: 60g of natural rubber and 40g of cis-butadiene rubber are uniformly mixed and then placed into a plasma treatment chamber, the chamber is closed and vacuumized to 10Pa; argon is introduced to maintain the pressure in the chamber at 50Pa, a radio frequency power source is turned on, the power is set to 90W, and the modified rubber is obtained after 60s of treatment.

[0058] Preparation Example 9

[0059] The preparation example discloses a preparation process of modified rubber, specifically: 60g of natural rubber and 40g of cis-butadiene rubber are uniformly mixed and then placed into a plasma treatment chamber, the chamber is closed and vacuumized to 10Pa; a mixed gas of oxygen and argon with a volume ratio of 2:8 is introduced to maintain the pressure in the chamber at 50Pa, a radio frequency power source is turned on, the power is set to 90W, and the modified rubber is obtained after 60s of treatment.

[0060] Preparation Example 10

[0061] The preparation example discloses a preparation process of modified rubber, specifically: 60g of natural rubber and 40g of cis-butadiene rubber are uniformly mixed and then placed into a plasma treatment chamber, the chamber is closed and vacuumized to 10Pa; a mixed gas of oxygen and argon with a volume ratio of 3:7 is introduced to maintain the pressure in the chamber at 50Pa, a radio frequency power source is turned on, the power is set to 90W, and the modified rubber is obtained after 60s of treatment.

[0062] Preparation Example 11

[0063] The preparation example discloses a preparation process of modified rubber, specifically as follows: 60 g of natural rubber and 40 g of butadiene rubber are uniformly mixed and then put into a plasma treatment chamber; the chamber is closed and vacuumized to 10 Pa; mixed gas of oxygen and argon with a volume ratio of 4:6 is introduced, the pressure in the chamber is maintained at 50 Pa, a radio frequency power supply is turned on, the power is set to 90 W, and the modified rubber is obtained after 60 s of treatment.

[0064] Preparation example 12-17 polydopamine modified carbon black

[0065] Preparation example 12

[0066] The preparation example discloses a preparation process of polydopamine modified carbon black, specifically including the following steps:

[0067] (1) The N330 carbon black is washed with deionized water for 3 times, and then vacuum dried at 70℃ for 5h to obtain the impurity-removed carbon black. 100g of the impurity-removed carbon black is added into 10L of deionized water, and ultrasonic treatment is performed for 45min under a power of 400W to form a suspension;

[0068] (2) 0.05mol / L Tris-HCl buffer solution is prepared: 6.057g of tris-hydroxymethyl aminomethane is taken and added into 800mL of deionized water, and stirred until completely dissolved. The pH meter electrode is put into the solution, and concentrated hydrochloric acid is slowly added while stirring until the pH of the solution is 8.5. The beaker and glass rod are rinsed with a small amount of deionized water, and the rinsing liquid is poured into the solution with the adjusted pH, and deionized water is added to make up to 1L to obtain the 0.05mol / L Tris-HCl buffer solution;

[0069] (3) The Tris-HCl buffer solution is added to the suspension, and the pH of the system is adjusted to 8. Slowly add 50g of dopamine hydrochloride, continue to stir and control the reaction temperature to be 25℃, and react for 10h;

[0070] (4) After the reaction is completed, the mixture is centrifuged at a speed of 10000rpm for 10min, and the black precipitate at the bottom is collected, and the precipitate is repeatedly washed with deionized water until the supernatant is colorless to obtain carbon black-polydopamine. The carbon black-polydopamine is placed in a vacuum drying oven and dried at 70℃ for 18h until the weight is constant. The dried product is ground through a 200 mesh sieve to obtain polydopamine modified carbon black.

[0071] Preparation example 13

[0072] The preparation example discloses a preparation process of polydopamine modified carbon black, specifically including the following steps:

[0073] (1) The N330 carbon black is washed with deionized water for 3 times, and then dried at 70°C under vacuum for 5h to obtain impurity-removed carbon black. 100g of the impurity-removed carbon black is added into 10L of deionized water, and ultrasonic treatment is performed at a power of 400W for 45min to form a suspension;

[0074] (2) A 0.05mol / L Tris-HCl buffer solution is prepared: 6.057g of Tris is added into 800mL of deionized water, and stirred until completely dissolved. A pH meter electrode is placed into the solution, and concentrated hydrochloric acid is slowly added dropwise while stirring until the pH of the solution is 8.5. A small amount of deionized water is used to rinse the beaker and glass rod, and the rinsing liquid is poured into the solution with the adjusted pH, and deionized water is added to make up to 1L to obtain the 0.05mol / L Tris-HCl buffer solution;

[0075] (3) The Tris-HCl buffer solution is added into the suspension, and the pH of the system is adjusted to 8.5. 20g of dopamine hydrochloride is slowly added, and stirring is continued while the reaction temperature is controlled at 25°C. The reaction is carried out for 10h;

[0076] (4) After the reaction is completed, the mixture is centrifuged at a speed of 10000rpm for 10min, and the black precipitate at the bottom is collected. The precipitate is repeatedly washed with deionized water until the supernatant is colorless to obtain carbon black-polydopamine. The carbon black-polydopamine is placed in a vacuum drying oven and dried at 70°C for 18h until the weight is constant. The dried product is ground through a 200-mesh sieve to obtain polydopamine-modified carbon black.

[0077] Preparation Example 14

[0078] The preparation example discloses a preparation process of polydopamine-modified carbon black, which specifically comprises the following steps:

[0079] (1) The N330 carbon black is washed with deionized water for 3 times, and then dried at 70°C under vacuum for 5h to obtain impurity-removed carbon black. 100g of the impurity-removed carbon black is added into 10L of deionized water, and ultrasonic treatment is performed at a power of 400W for 45min to form a suspension;

[0080] (2) A 0.05mol / L Tris-HCl buffer solution is prepared: 6.057g of Tris is added into 800mL of deionized water, and stirred until completely dissolved. A pH meter electrode is placed into the solution, and concentrated hydrochloric acid is slowly added dropwise while stirring until the pH of the solution is 8.5. A small amount of deionized water is used to rinse the beaker and glass rod, and the rinsing liquid is poured into the solution with the adjusted pH, and deionized water is added to make up to 1L to obtain the 0.05mol / L Tris-HCl buffer solution;

[0081] (3) Add the Tris-HCl buffer solution to the suspension and adjust the pH of the system to 8.5; slowly add 10 g of dopamine hydrochloride, continue to stir and control the reaction temperature to be 25°C, and react for 10 h;

[0082] (4) After the reaction is completed, centrifuge the mixture at a speed of 10,000 rpm for 10 min, collect the black precipitate at the bottom, and repeatedly wash the precipitate with deionized water until the supernatant is colorless to obtain carbon black-polydopamine; place the carbon black-polydopamine in a vacuum drying oven and dry at 70°C for 18 h until the weight is constant; grind the dried product through a 200-mesh sieve to obtain polydopamine-modified carbon black.

[0083] Preparation Example 15

[0084] This preparation example is basically the same as Preparation Example 13, except that in step (1), the N330 carbon black is washed with deionized water for 3 times, then vacuum dried at 70°C for 5 h to obtain impurity-removed carbon black, 100 g of the impurity-removed carbon black is added into 1 L of 65 wt% nitric acid solution to form a mixture, heated to 60°C under stirring, and reacted for 6 h; after the reaction is completed, the mixture is cooled to room temperature, then poured into deionized water, stirred, and then suction filtered; the filter cake is washed until the pH of the filtrate is 5; the washed filter cake is placed in a vacuum drying oven at 80°C and dried for 12 h; after grinding, the oxidized carbon black is obtained; 100 g of the impurity-removed carbon black is added into 10 L of deionized water, and ultrasonic treatment is performed at a power of 400 W for 45 min to form a suspension.

[0085] Preparation Example 16

[0086] This preparation example is basically the same as Preparation Example 13, except that in step (1), the N330 carbon black is washed with deionized water for 3 times, then vacuum dried at 70°C for 5 h to obtain impurity-removed carbon black, 100 g of the impurity-removed carbon black is added into 1.5 L of 65 wt% nitric acid solution to form a mixture, heated to 80°C under stirring, and reacted for 4 h; after the reaction is completed, the mixture is cooled to room temperature, then poured into deionized water, stirred, and then suction filtered; the filter cake is washed until the pH of the filtrate is 6; the washed filter cake is placed in a vacuum drying oven at 90°C and dried for 10 h; after grinding, the oxidized carbon black is obtained; 100 g of the impurity-removed carbon black is added into 10 L of deionized water, and ultrasonic treatment is performed at a power of 400 W for 45 min to form a suspension.

[0087] Preparation Example 17

[0088] The preparation example is basically the same as preparation example 13, except that in step (1), the N330 carbon black is washed with deionized water for 3 times, then vacuum dried at 70℃ for 5h to obtain the impurity-removed carbon black, 100g of the impurity-removed carbon black is added into 2L of 65wt% nitric acid solution to form a mixture, heated to 80℃ under stirring, and reacted for 2h, after the reaction, cooled to room temperature, the mixture is poured into deionized water, stirred and then filtered, the filter cake is washed until the pH of the filtrate is 7, the washed filter cake is vacuum dried at 100℃ for 8h, and then ground to obtain the oxidized carbon black; 100g of the impurity-removed carbon black is added into 10L of deionized water, and ultrasonic treated for 45min under 400W power to form a suspension.

[0089] Example 1

[0090] The present embodiment provides a high wear-resistant and high-strength conveyor belt, which comprises a cover rubber and a skeleton layer, wherein the cover rubber comprises the following raw materials: modified rubber 10kg, polydopamine modified carbon black 4.5kg, vulcanizing agent 0.5kg, active agent 0.75kg, and antioxidant 4010NA 0.1kg, wherein the modified rubber is obtained by preparation example 1, the polydopamine modified carbon black is obtained by preparation example 12, the vulcanizing agent is 0.3kg of sulfur, 0.15kg of accelerator NS, and 0.05kg of accelerator DM, and the active agent is 0.6kg of zinc oxide and 0.15kg of stearic acid.

[0091] The present embodiment also provides a preparation process of the above-mentioned high wear-resistant and high-strength conveyor belt, which comprises the following steps:

[0092] Mixing: the modified rubber is weighed according to the formula and put into the internal mixer, and plasticated for 2min under the condition of initial temperature 80℃ and rotating speed 60r / min; 2.25kg of polydopamine modified carbon black is added and mixed for 3min, and the temperature is controlled at 110℃ during the mixing; then zinc oxide, stearic acid and antioxidant 4010NA are added and mixed for 2min, and the rubber is discharged when the temperature is not more than 125℃ to obtain the mixed rubber; the mixed rubber is put into the internal mixer again under the condition of initial temperature 90℃ and rotating speed 50r / min, 2.25kg of polydopamine modified carbon black is added and mixed for 3min; accelerator NS, accelerator DM and sulfur are added and mixed for 2min, and the rubber is discharged when the temperature is not more than 110℃ to obtain the internal mixed rubber;

[0093] Opening: the above-mentioned internal mixed rubber is transferred to the open mill, the roller temperature is controlled at 55℃, the roller distance is adjusted to 1mm, and thin passing is performed for 5 times; then the roller distance is adjusted to 3mm, and triangle bagging and rolling are performed for 3 times respectively, finally the rubber sheet with a thickness of 4mm is obtained by tabletting, and the rubber sheet is stored at room temperature for 24h for standby; the opened rubber sheet is put into the screw extruder, and the extrusion temperature is set to 110℃, and the rubber material with a thickness of 4mm is obtained by extrusion.

[0094] Frame layer: the steel wire rope is soaked in gasoline for 30 min, and then dried by hot air after taking out; the resorcinol-formaldehyde-latex system (RFL adhesive) is uniformly coated on the surface of the steel wire rope core, the coating amount is 5 g / m, and then dried in an oven at 80°C for 10 min;

[0095] Calendering: the extruded rubber and the arranged steel wire rope core are compounded on the calendering machine, the calendering temperature is 110°C, and the pressure is 4 MPa, so that the rubber uniformly covers the steel wire rope core to form a conveyor belt blank with a thickness of 10 mm; the conveyor belt blank is placed in a flat curing press, the curing temperature is set to 150°C, the curing pressure is 10 MPa, and the curing time is 20 min; after curing, the conveyor belt is taken out and naturally cooled to below 40°C at room temperature; trimming is performed to remove excess rubber to obtain the conveyor belt.

[0096] Example 2

[0097] This example is basically the same as example 1, except that the covering rubber in this example includes the following raw materials: modified rubber 10 kg, polydopamine modified carbon black 5 kg, vulcanizing agent 0.45 kg, active agent 0.7 kg, and antioxidant 4010NA 0.15 kg, wherein the modified rubber is obtained by preparation example 1, the polydopamine modified carbon black is obtained by preparation example 12, the vulcanizing agent is 0.25 kg of sulfur, 0.125 kg of accelerator NS, and 0.075 kg of accelerator DM, and the active agent is 0.5 kg of zinc oxide and 0.2 kg of stearic acid.

[0098] Example 3

[0099] This example is basically the same as example 1, except that the covering rubber in this example includes the following raw materials: modified rubber 10 kg, polydopamine modified carbon black 5.5 kg, vulcanizing agent 0.4 kg, active agent 0.65 kg, and antioxidant 4010NA 0.2 kg, wherein the modified rubber is obtained by preparation example 1, the polydopamine modified carbon black is obtained by preparation example 12, the vulcanizing agent is 0.2 kg of sulfur, 0.1 kg of accelerator NS, and 0.1 kg of accelerator DM, and the active agent is 0.4 kg of zinc oxide and 0.25 kg of stearic acid.

[0100] Example 4

[0101] This example is basically the same as example 2, except that the covering rubber in this example includes the following raw materials: modified rubber 10 kg, polydopamine modified carbon black 5 kg, vulcanizing agent 0.45 kg, active agent 0.7 kg, and antioxidant 4010NA 0.15 kg, wherein the modified rubber is obtained by preparation example 2, the polydopamine modified carbon black is obtained by preparation example 12, the vulcanizing agent is 0.25 kg of sulfur, 0.125 kg of accelerator NS, and 0.075 kg of accelerator DM, and the active agent is 0.5 kg of zinc oxide and 0.2 kg of stearic acid.

[0102] Example 5

[0103] This example is substantially identical to Example 2, except that in this example the cover stock comprises the following ingredients: modified rubber 10 kg, polydopamine modified carbon black 5 kg, vulcanizing agent 0.45 kg, active agent 0.7 kg, and antioxidant 4010NA 0.15 kg, wherein the modified rubber is obtained from Preparation Example 3, the polydopamine modified carbon black is obtained from Preparation Example 12, the vulcanizing agent is 0.25 kg of sulfur, 0.125 kg of accelerator NS, and 0.075 kg of accelerator DM, and the active agent is 0.5 kg of zinc oxide and 0.2 kg of stearic acid.

[0104] Example 6

[0105] This example is substantially identical to Example 2, except that in this example the cover stock comprises the following ingredients: modified rubber 10 kg, polydopamine modified carbon black 5 kg, vulcanizing agent 0.45 kg, active agent 0.7 kg, and antioxidant 4010NA 0.15 kg, wherein the modified rubber is obtained from Preparation Example 4, the polydopamine modified carbon black is obtained from Preparation Example 12, the vulcanizing agent is 0.25 kg of sulfur, 0.125 kg of accelerator NS, and 0.075 kg of accelerator DM, and the active agent is 0.5 kg of zinc oxide and 0.2 kg of stearic acid.

[0106] Example 7

[0107] This example is substantially identical to Example 2, except that in this example the cover stock comprises the following ingredients: modified rubber 10 kg, polydopamine modified carbon black 5 kg, vulcanizing agent 0.45 kg, active agent 0.7 kg, and antioxidant 4010NA 0.15 kg, wherein the modified rubber is obtained from Preparation Example 5, the polydopamine modified carbon black is obtained from Preparation Example 12, the vulcanizing agent is 0.25 kg of sulfur, 0.125 kg of accelerator NS, and 0.075 kg of accelerator DM, and the active agent is 0.5 kg of zinc oxide and 0.2 kg of stearic acid.

[0108] Example 8

[0109] This example is substantially identical to Example 2, except that in this example the cover stock comprises the following ingredients: modified rubber 10 kg, polydopamine modified carbon black 5 kg, vulcanizing agent 0.45 kg, active agent 0.7 kg, and antioxidant 4010NA 0.15 kg, wherein the modified rubber is obtained from Preparation Example 6, the polydopamine modified carbon black is obtained from Preparation Example 12, the vulcanizing agent is 0.25 kg of sulfur, 0.125 kg of accelerator NS, and 0.075 kg of accelerator DM, and the active agent is 0.5 kg of zinc oxide and 0.2 kg of stearic acid.

[0110] Example 9

[0111] This example is substantially identical to Example 2, except that in this example the cover stock comprises the following ingredients: modified rubber 10 kg, polydopamine modified carbon black 5 kg, vulcanizing agent 0.45 kg, active agent 0.7 kg, and antioxidant 4010NA 0.15 kg, wherein the modified rubber is obtained in Preparation Example 7, the polydopamine modified carbon black is obtained in Preparation Example 12, the vulcanizing agent is 0.25 kg of sulfur, 0.125 kg of accelerator NS, and 0.075 kg of accelerator DM, and the active agent is 0.5 kg of zinc oxide and 0.2 kg of stearic acid.

[0112] Example 10

[0113] This example is substantially identical to Example 2, except that in this example the cover stock comprises the following ingredients: modified rubber 10 kg, polydopamine modified carbon black 5 kg, vulcanizing agent 0.45 kg, active agent 0.7 kg, and antioxidant 4010NA 0.15 kg, wherein the modified rubber is obtained in Preparation Example 8, the polydopamine modified carbon black is obtained in Preparation Example 12, the vulcanizing agent is 0.25 kg of sulfur, 0.125 kg of accelerator NS, and 0.075 kg of accelerator DM, and the active agent is 0.5 kg of zinc oxide and 0.2 kg of stearic acid.

[0114] Example 11

[0115] This example is substantially identical to Example 2, except that in this example the cover stock comprises the following ingredients: modified rubber 10 kg, polydopamine modified carbon black 5 kg, vulcanizing agent 0.45 kg, active agent 0.7 kg, and antioxidant 4010NA 0.15 kg, wherein the modified rubber is obtained in Preparation Example 9, the polydopamine modified carbon black is obtained in Preparation Example 12, the vulcanizing agent is 0.25 kg of sulfur, 0.125 kg of accelerator NS, and 0.075 kg of accelerator DM, and the active agent is 0.5 kg of zinc oxide and 0.2 kg of stearic acid.

[0116] Example 12

[0117] This example is substantially identical to Example 2, except that in this example the cover stock comprises the following ingredients: modified rubber 10 kg, polydopamine modified carbon black 5 kg, vulcanizing agent 0.45 kg, active agent 0.7 kg, and antioxidant 4010NA 0.15 kg, wherein the modified rubber is obtained in Preparation Example 10, the polydopamine modified carbon black is obtained in Preparation Example 12, the vulcanizing agent is 0.25 kg of sulfur, 0.125 kg of accelerator NS, and 0.075 kg of accelerator DM, and the active agent is 0.5 kg of zinc oxide and 0.2 kg of stearic acid.

[0118] Example 13

[0119] This example is basically the same as example 2, except that the covering glue in this example comprises the following raw materials: modified rubber 10 kg, polydopamine modified carbon black 5 kg, vulcanizing agent 0.45 kg, active agent 0.7 kg, and antioxidant 4010NA 0.15 kg, wherein the modified rubber is obtained by preparation example 10, the polydopamine modified carbon black is obtained by preparation example 13, the vulcanizing agent is 0.25 kg of sulfur, 0.125 kg of accelerator NS, and 0.075 kg of accelerator DM, and the active agent is 0.5 kg of zinc oxide and 0.2 kg of stearic acid.

[0120] Example 14

[0121] This example is basically the same as example 2, except that the covering glue in this example comprises the following raw materials: modified rubber 10 kg, polydopamine modified carbon black 5 kg, vulcanizing agent 0.45 kg, active agent 0.7 kg, and antioxidant 4010NA 0.15 kg, wherein the modified rubber is obtained by preparation example 10, the polydopamine modified carbon black is obtained by preparation example 13, the vulcanizing agent is 0.25 kg of sulfur, 0.125 kg of accelerator NS, and 0.075 kg of accelerator DM, and the active agent is 0.5 kg of zinc oxide and 0.2 kg of stearic acid.

[0122] Example 15

[0123] This example is basically the same as example 2, except that the covering glue in this example comprises the following raw materials: modified rubber 10 kg, polydopamine modified carbon black 5 kg, vulcanizing agent 0.45 kg, active agent 0.7 kg, and antioxidant 4010NA 0.15 kg, wherein the modified rubber is obtained by preparation example 10, the polydopamine modified carbon black is obtained by preparation example 14, the vulcanizing agent is 0.25 kg of sulfur, 0.125 kg of accelerator NS, and 0.075 kg of accelerator DM, and the active agent is 0.5 kg of zinc oxide and 0.2 kg of stearic acid.

[0124] Example 16

[0125] This example is basically the same as example 2, except that the covering glue in this example comprises the following raw materials: modified rubber 10 kg, polydopamine modified carbon black 5 kg, vulcanizing agent 0.45 kg, active agent 0.7 kg, and antioxidant 4010NA 0.15 kg, wherein the modified rubber is obtained by preparation example 10, the polydopamine modified carbon black is obtained by preparation example 15, the vulcanizing agent is 0.25 kg of sulfur, 0.125 kg of accelerator NS, and 0.075 kg of accelerator DM, and the active agent is 0.5 kg of zinc oxide and 0.2 kg of stearic acid.

[0126] Example 17

[0127] This example is substantially the same as Example 2, except that in this example the cover compound includes the following raw materials: modified rubber 10 kg, polydopamine-modified carbon black 5 kg, vulcanizing agent 0.45 kg, active agent 0.7 kg, and antioxidant 4010NA 0.15 kg, wherein the modified rubber is obtained by using the product of Preparation Example 10, the polydopamine-modified carbon black is obtained by using the product of Preparation Example 16, the vulcanizing agent is 0.25 kg of sulfur, 0.125 kg of accelerator NS, and 0.075 kg of accelerator DM, and the active agent is 0.5 kg of zinc oxide and 0.2 kg of stearic acid.

[0128] Example 18

[0129] This example is substantially the same as Example 2, except that in this example the cover compound includes the following raw materials: modified rubber 10 kg, polydopamine-modified carbon black 5 kg, vulcanizing agent 0.45 kg, active agent 0.7 kg, and antioxidant 4010NA 0.15 kg, wherein the modified rubber is obtained by using the product of Preparation Example 10, the polydopamine-modified carbon black is obtained by using the product of Preparation Example 16, the vulcanizing agent is 0.25 kg of sulfur, 0.125 kg of accelerator NS, and 0.075 kg of accelerator DM, and the active agent is 0.5 kg of zinc oxide and 0.2 kg of stearic acid.

[0130] Comparative Example 1

[0131] This comparative example is substantially the same as Example 1, except that in this comparative example the cover compound includes the following raw materials: natural rubber 10 kg, carbon black 4.5 kg, vulcanizing agent 0.5 kg, active agent 0.75 kg, and antioxidant 4010NA 0.1 kg, wherein the vulcanizing agent is 0.3 kg of sulfur, 0.15 kg of accelerator NS, and 0.05 kg of accelerator DM, and the active agent is 0.6 kg of zinc oxide and 0.15 kg of stearic acid.

[0132] Comparative Example 2

[0133] This comparative example is substantially the same as Example 1, except that in this comparative example the cover compound includes the following raw materials: modified rubber 10 kg, carbon black 4.5 kg, vulcanizing agent 0.5 kg, active agent 0.75 kg, and antioxidant 4010NA 0.1 kg, wherein the modified rubber is obtained by using the product of Preparation Example 1, the vulcanizing agent is 0.3 kg of sulfur, 0.15 kg of accelerator NS, and 0.05 kg of accelerator DM, and the active agent is 0.6 kg of zinc oxide and 0.15 kg of stearic acid.

[0134] Comparative Example 3

[0135] The comparative example is basically the same as example 1, except that the covering glue in the comparative example comprises the following raw materials: natural rubber 10 kg, polydopamine modified carbon black 4.5 kg, vulcanizing agent 0.5 kg, active agent 0.75 kg and antioxidant 4010NA 0.1 kg, wherein the polydopamine modified carbon black is obtained by preparation example 12, the vulcanizing agent is 0.3 kg of sulfur, 0.15 kg of accelerator NS and 0.05 kg of accelerator DM, and the active agent is 0.6 kg of zinc oxide and 0.15 kg of stearic acid.

[0136] Performance detection

[0137] Detection standard:

[0138] Tensile strength test: the tensile strength of the conveyor belts prepared in examples 1-18 and comparative examples 1-3 is detected according to GB / T528-2009 “Determination of tensile stress-strain properties of vulcanized or thermoplastic rubber”, and the test results are recorded in table 1.

[0139] Abrasion resistance test: the abrasion volume of the conveyor belts prepared in examples 1-18 and comparative examples 1-3 is detected according to GB / T1689-2014 “Test methods for abrasion resistance of vulcanized rubber (using an Akron abrasion tester)”, and the test results are recorded in table 1.

[0140] Table 1 Performance detection data of high abrasion resistance and high strength conveyor belts in examples 1-18 and comparative examples 1-3

[0141]

[0142] According to table 1, combined with examples 1 and comparative examples 1-3, it can be seen that the rubber treated by plasma in the application is bonded with polydopamine modified carbon black, and the rough structure on the surface of the modified carbon black can form physical anchoring with the surface of the rubber, and the amphoteric property of polydopamine can promote the uniform dispersion of carbon black in rubber. Through the synergistic effect of chemical bonding, physical embedding and dispersion optimization, the compatibility of rubber and carbon black is improved, and the tensile properties and abrasion resistance of the prepared conveyor belt are improved.

[0143] According to table 1, combined with examples 8, 10-13, it can be seen that the use of mixed gas of oxygen and argon for plasma treatment of rubber has better modification effect than the use of single gas, and the prepared conveyor belt has better mechanical properties and abrasion resistance; wherein oxygen can introduce polar oxygen-containing groups on the surface of rubber, enhance the polar interaction with carbon black; argon as an inert gas mainly plays a etching role, increases the roughness of the surface of rubber, promotes the physical anchoring effect, so that the modified rubber and polydopamine modified carbon black are combined through the combination mode of chemical bonding and physical anchoring, and the combination of the two is improved.

[0144] Referring to Table 1, in combination with Examples 14 and 16-18, it can be seen that, before the polydopamine modification of the carbon black, the present application is subjected to an oxidation treatment, which can introduce more carboxyl groups, so that the polarity of the carbon black surface is significantly improved, on the one hand, providing abundant reaction sites for the subsequent polydopamine modification, ensuring that the polydopamine coating can be firmly anchored on the surface of the carbon black; on the other hand, after the oxidation treatment combined with the polydopamine modification, the polarity of the carbon black surface is highly matched with the polar surface of the plasma-treated rubber, greatly reducing the interfacial tension; at the same time, the strong dipole interaction and electrostatic attraction between the polar groups of the polydopamine and the polar groups on the surface of the rubber can further enhance the interfacial adsorption, further improving the combination of the two, improving the wear resistance and tensile strength of the prepared conveyor belt.

[0145] The specific embodiments are merely illustrative of the present application, and are not a limitation of the present application. Those skilled in the art can make modifications to the embodiments without creative contribution after reading the present specification, as long as the modifications are within the scope of the claims of the present application.

Claims

1. A high abrasion resistant high strength conveyor belt comprising a cover compound and a carcass layer, characterized in that, The covering glue comprises the following raw materials in parts by weight: modified rubber 100 parts, polydopamine modified carbon black 45-55 parts, vulcanizing agent 4-5 parts, active agent 6.5-7.5 parts and antioxidant 1-2 parts; the modified rubber is plasma treated rubber; The preparation process of the modified rubber is as follows: the rubber is placed in a plasma device, a gas is introduced, the pressure in the chamber is maintained at 40-60 Pa, the power is set to 80-100 W, and the treatment is performed for 40-80 s; wherein the gas is a mixed gas of oxygen and argon in a volume ratio of (2-4):(6-8); The preparation process of the polydopamine modified carbon black comprises the following steps: (1) ultrasonic dispersion of carbon black in deionized water to obtain a suspension; (2) adding the suspension into a Tris-HCl buffer solution, adjusting the pH of the system to 8.0-8.5, adding a dopamine monomer, reacting, washing and drying to obtain polydopamine modified carbon black; The carbon black is further subjected to oxidation treatment before being modified with polydopamine, specifically: adding carbon black into a nitric acid solution to form a mixture, heating to 60-100℃ under stirring, reacting for 2-6h, after the reaction is completed, cooling to room temperature, pouring the mixture into deionized water, stirring and then suction filtering, washing the filter cake until the pH of the filtrate is 5-7, placing the washed filter cake in a vacuum dryer at 80-100℃ for 8-12h, and grinding to obtain oxidized carbon black.

2. The high abrasion high strength conveyor belt of claim 1, wherein, The rubber is a mixture of natural rubber and butadiene rubber in a mass ratio of (55-65):(35-45).

3. The high abrasion high strength conveyor belt of claim 1, wherein, The mass ratio of the dopamine monomer to carbon black is 1:(2-10).

4. The high abrasion high strength conveyor belt of claim 1, wherein, The mass-volume ratio of the carbon black to the nitric acid solution is 1:(10-20) g / mL.

5. The high abrasion high strength conveyor belt of claim 1, wherein, The carbon black is one of N110 carbon black, N220 carbon black, N330 carbon black and N550 carbon black.

6. The high abrasion high strength conveyor belt of claim 1, wherein, The vulcanizing agent is a mixture of sulfur and an accelerator in a mass ratio of (2-3):2; the accelerator is a mixture of accelerator NS and accelerator DM in a mass ratio of (2-3):(1-2).

7. The high abrasion high strength conveyor belt of claim 1, wherein, The active agent is a mixture of zinc oxide and stearic acid in a mass ratio of (8-12):(3-5).

8. A process for the production of a high abrasion high strength conveyor belt as claimed in any one of claims 1 to 7, characterised in that, The method comprises the following steps: The raw materials of the covering glue are weighed according to the formula and mixed to obtain a mixed rubber, the mixed rubber is opened to obtain a rubber sheet, and the rubber sheet is extruded to obtain a rubber material; The adhesive is uniformly coated on the surface of the steel wire rope core and then dried to obtain a skeleton layer; The rubber material and the skeleton layer are calendered to obtain a conveyor belt blank; The conveyor belt blank is vulcanized to obtain a conveyor belt.

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