Rubber wheel for tire cutting machine and preparation method of rubber wheel

Abstract

The invention provides a rubber wheel for a tire cutting machine, which is prepared from the following components in parts by weight: 0 to 50 parts of butadiene rubber, 50 to 100 parts of emulsion polymerized styrene-butadiene rubber SBR 1502, 3 to 5 parts of zinc oxide, 1 to 2 parts of stearic acid, 50 to 70 parts of carbon black, 0.5 to 2.0 parts of high-content anti-aging agent, 2 to 3 parts of tackifying resin, 0 to 15 parts of liquid butadiene rubber, 0 to 1 part of sulfur, 1.5 to 5 parts of accelerant NS and 2.5 to 5 parts of super vulcanizing agent. The liquid butadiene rubber is used for replacing an environment-friendly rubber plasticizer to improve the abrasion performance of the rubber wheel before and after aging, and the emulsion polymerized styrene-butadiene rubber SBR 1502 is used for replacing 20 # standard natural rubber, so that the abrasion performance of the rubber wheel after aging is further improved on the premise of ensuring certain strength, but heat generation is increased; by using the super vulcanizing agent and adjusting the vulcanization system, the heat generation of the rubber material is obviously reduced, the stress at definite elongation is improved, the aging resistance is improved, the service life of the rubber wheel is prolonged, the purchase cost is reduced, and the working efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of rubber production, and particularly relates to a rubber wheel for a tire cutting machine and a preparation method thereof. Background Art

[0002] In the tire industry, for finished product analysis, structural design, etc., tire cross-sections are required. In the tire industry, tire cutting machines are generally used to cut tires to produce tire cross-sections. The tire cutting machine cuts the tire through the high-speed movement of a special metal wire. The special metal wire moves for cutting by being wound around a plurality of metal cutting wheels of different sizes. A rubber wheel is adhered to the outer edge of the metal cutting wheel. The rubber wheel is in direct contact with the special metal wire, playing a role in protecting the metal cutting wheel and the special metal wire. At the same time, a deep groove is provided in the middle position of the rubber wheel, and the special metal wire moves in the deep groove of the rubber wheel to ensure that the movement track does not deviate. The structure of the cutting wheel is shown in the appendix Figure 1 .

[0003] Since the rubber wheel will be worn after being used for a period of time, the special metal wire will vibrate, resulting in an unclear surface of the cut tire cross-section. When the special metal wire vibrates, the rubber wheel needs to be replaced. When replacing, it needs to be removed from the cutting machine, and often multiple rubber wheels need to be replaced at the same time.

[0004] Currently, the rubber wheels used in cutting machines need to be purchased from the suppliers of the cutting machines. The rubber wheels are usually severely worn after being used for about one month, resulting in the vibration of the metal wire. Therefore, it is necessary to frequently purchase and replace the rubber wheels, with high procurement costs, short service life, and low work efficiency. Summary of the Invention

[0005] The purpose of the present invention is to solve the above-mentioned technical deficiencies and provide a rubber wheel for a tire cutting machine and a preparation method thereof.

[0006] For this purpose, the present invention provides a rubber wheel for a tire cutting machine, which comprises the following components in parts by weight: 0 - 50 parts of cis-butadiene rubber, 50 - 100 parts of emulsion-polymerized styrene-butadiene rubber SBR 1502, 3 - 5 parts of zinc oxide, 1 - 2 parts of stearic acid, 50 - 70 parts of carbon black, 0.5 - 2.0 parts of high-content antioxidant, 2 - 3 parts of tackifying resin, 0 - 15 parts of liquid cis-butadiene rubber, 0 - 1 part of sulfur, 1.5 - 5 parts of accelerator NS, 2.5 - 5 parts of super vulcanizing agent, 0 - 3 parts of resorcinol formaldehyde resin, 0 - 3 parts of adhesive;

[0007] The super vulcanizing agent is a long-chain molecule with a sulfur content of 31% - 33%, and the molecular structure is:

[0008]

[0009] Among them, X is 2 - 6, n is 3 - 8, R1 is an alkyl chain with 2 - 20 carbon atoms, and R2 is an alkyl chain with 2 - 8 carbon atoms.

[0010] Preferably, the emulsion polymerized styrene - butadiene rubber SBR 1502 is SBR 1502 produced by low - temperature emulsion polymerization using styrene and butadiene as monomers; the liquid cis - 1,4 - polybutadiene rubber is a liquid butadiene rubber with a kinematic viscosity of 2.7 - 3.3 mPa·s at 20°C.

[0011] Preferably, the cis - 1,4 - polybutadiene rubber is nickel - based cis - 1,4 - polybutadiene BR9000; the carbon black is N115, N121, N220, N234, or a low - heat - generating non - standard carbon black with a nitrogen adsorption specific surface area 8 - 10 values higher than the iodine adsorption value; the high - content antioxidant is an antioxidant STMQ with a total content of dimers, trimers, and tetramers greater than 70%; the tackifying resin is an octylphenol formaldehyde resin; the accelerator NS is N - tert - butyl - 2 - benzothiazole sulfenamide, and the molecular formula is C 11 H 14 N2S.

[0012] Preferably, the resorcinol formaldehyde resin is a polycondensation product obtained by the reaction of resorcinol and formaldehyde, and the molecular formula is C6H6O2·CH2O.

[0013] Preferably, the adhesive is composed of hexamethoxymethylmelamine and an inorganic carrier. The content of hexamethoxymethylmelamine is 65%, and the inorganic carrier is ordinary silica or highly dispersed silica.

[0014] A preparation method of a rubber wheel for a tire cutting machine includes the following steps:

[0015] S1. Press the cis - 1,4 - polybutadiene rubber and the emulsion polymerized styrene - butadiene rubber SBR 1502 with a rotor speed of 65 - 80 r / min in a Banbury mixer for 25 - 30 s to obtain a mixture one;

[0016] S2. Add carbon black, zinc oxide, stearic acid, high - content antioxidant, liquid cis - 1,4 - polybutadiene rubber, tackifying resin, and resorcinol formaldehyde resin to the mixture one. The rotor speed of the Banbury mixer first decreases and then increases, and after heating, a mixture two is obtained. Then, discharge the rubber, take out the sheet, and cool it;

[0017] S3. Add sulfur, accelerator NS, super vulcanizing agent, and adhesive to the mixture two. After the rotor speed of the Banbury mixer is reduced at low temperature, discharge the rubber, take out the sheet, and cool it to obtain the rubber wheel stock. After extrusion, the rubber wheel stock is made into a rubber wheel sheet;

[0018] S4. Place the metal cutting wheel coated with a curing agent into a vulcanization mold, wind the rubber wheel sheet around its outer edge, and put it into a vulcanizer for vulcanization to obtain a semi - finished rubber wheel;

[0019] S5. After vulcanization, engrave grooves on the outer ring of the semi - finished rubber wheel to obtain the finished rubber wheel.

[0020] Preferably, in S2, the kneader ram is pressed for 25 - 30 s, the rotor speed is reduced to 40 - 50 r / min, after cleaning, the ram is pressed again for 25 - 30 s, after lifting the ram, the rotor speed is increased to 50 - 55 r / min, and the ram is pressed until the rubber is discharged at 155 - 160 °C.

[0021] Preferably, in S3, the kneader ram is pressed for 20 - 30 s and then cleaned, the rotor speed is reduced from 50 - 60 r / min to 35 - 40 r / min, the ram is pressed for 20 - 30 s, then the ram is lifted for 5 - 10 s, and then the ram is pressed until the rubber is discharged at 95 - 100 °C.

[0022] Preferably, in S4, the rubber wheel compound is vulcanized in a vulcanizer at a pressure of 40 T and at 140 - 150 °C for 1.5 - 2.5 h to obtain a semi-finished rubber wheel.

[0023] Preferably, the ram pressure of the kneader is 0.3 - 0.6 MPa.

[0024] The beneficial effects of the present invention are as follows: The present invention provides a rubber wheel for a tire cutting machine and its preparation method, and has the following beneficial effects.

[0025] Using liquid cis - 1,4 - polybutadiene rubber to replace the environmentally friendly rubber plasticizer, the abrasion resistance of the rubber wheel before and after aging is improved. Using emulsion - polymerized styrene - butadiene rubber SBR 1502 to replace 20# standard natural rubber, on the premise of ensuring a certain strength, the abrasion resistance after aging is further improved, but it will cause an increase in heat generation. By using a super vulcanizing agent and adjusting the vulcanization system, the heat generation of the compound is significantly reduced, the modulus at a specified elongation is increased, the aging resistance is improved, the service life of the rubber wheel is extended, the procurement cost is reduced, and the working efficiency is improved. Description of the Drawings

[0026] Figure 1 is a schematic structural diagram of the cutting wheel and the rubber wheel in the background art part;

[0027] Figure 2 is a schematic structural diagram of putting the metal cutting wheel wound with the rubber wheel compound into the vulcanization mold in the embodiment. Detailed Embodiments

[0028] The present invention will be further described below in conjunction with the drawings and specific embodiments to help understand the content of the present invention. The methods used in the present invention are all conventional methods unless otherwise specified; the raw materials and devices used are all conventional commercially available products unless otherwise specified.

[0029] The present invention provides a rubber wheel for a tire cutting machine, which comprises components in the following parts by weight: 0-50 parts of cis-butadiene rubber, 50-100 parts of emulsion-polymerized styrene-butadiene rubber SBR 1502, 3-5 parts of zinc oxide, 1-2 parts of stearic acid, 50-70 parts of carbon black, 0.5-2.0 parts of high-content antioxidant, 2-3 parts of tackifying resin, 0-15 parts of liquid cis-butadiene rubber, 0-1 part of sulfur, 1.5-5 parts of accelerator NS, 2.5-5 parts of super vulcanizing agent, 0-3 parts of resorcinol formaldehyde resin, and 0-3 parts of adhesive;

[0030] Further, the super vulcanizing agent is preferably 2.5-3 parts, and the accelerator NS is preferably 4.5-5 parts.

[0031] Specifically, the cis-butadiene rubber is nickel-based cis-butadiene BR9000;

[0032] The emulsion-polymerized styrene-butadiene rubber SBR 1502 is SBR 1502 produced by low-temperature emulsion polymerization using styrene and butadiene as monomers;

[0033] The zinc oxide is indirect method zinc oxide;

[0034] The stearic acid is industrial-grade stearic acid;

[0035] The carbon black is N115, N121, N220, N234 or a low heat build-up non-standard carbon black with a nitrogen adsorption specific surface area 8-10 values higher than the iodine adsorption value. In this embodiment, the carbon black is N234;

[0036] The high-content antioxidant is antioxidant STMQ with a total content of dimers, trimers and tetramers greater than 70%;

[0037] The tackifying resin is octylphenol formaldehyde resin, preferably WDH-B;

[0038] The liquid cis-butadiene rubber is a liquid butadiene rubber with a kinematic viscosity of 2.7-3.3 mPa·s at 20°C, preferably POLYVEST 130;

[0039] The accelerator NS is N-tert-butyl-2-benzothiazole sulfenamide, and its molecular formula is C 11 H 14 N2S;

[0040] The super vulcanizing agent is a long-chain molecule with a sulfur content of 31%-33%, and its molecular structure is:

[0041]

[0042] Among them, X is 2-6, n is 3-8, R1 is an alkyl chain with C2-C20, and R2 is an alkyl chain with C2-C8.

[0043] Resorcinol formaldehyde resin is a polycondensation product obtained by the reaction of resorcinol and formaldehyde, with the molecular formula C6H6O2·CH2O, and SL-3020LFR is preferred.

[0044] The binder consists of hexamethoxymethylmelamine and an inorganic carrier. The content of hexamethoxymethylmelamine is 65%, and the inorganic carrier is ordinary silica or highly dispersed silica, and RA is preferred.

[0045] A method for preparing a rubber wheel for a tire cutting machine includes the following steps:

[0046] S1. Put cis-butadiene rubber BR9000 and emulsion-polymerized styrene-butadiene rubber SBR 1502 into a 1.5L internal mixer, and mix at an initial rotor speed of 65 - 80 r / min and a ram pressure of 0.3 - 0.6 MPa for 25 - 30 s to obtain mixture one.

[0047] High-speed mixing can increase the shear force, promote the entanglement of the molecular chains of cis-butadiene rubber and emulsion-polymerized styrene-butadiene rubber, form a uniform blend network, and avoid phase separation; low ram pressure can prevent the agglomeration of fillers in the initial stage and lay a foundation for the subsequent dispersion of fillers.

[0048] S2. Add carbon black, zinc oxide, stearic acid, high-content antioxidant STMQ, liquid cis-butadiene rubber, tackifying resin and resorcinol formaldehyde resin to mixture one, and knead with the ram of the internal mixer for 25 - 30 s. Then reduce the rotor speed to 40 - 50 r / min, clean after kneading, and then knead with the ram for 25 - 30 s. After raising the ram, increase the rotor speed to 50 - 55 r / min, and knead with the ram until the temperature reaches 155 - 160 °C to obtain mixture two. Then discharge the rubber, cut it into sheets, and cool it.

[0049] The high speed in the initial stage can quickly mix the added fillers with mixture one and improve the mixing uniformity; reducing the speed in the later stage can prevent the excessive heat absorption of fillers such as carbon black, resulting in too fast heat generation and the destruction of the carbon black structure; cleaning after the first kneading with the ram can prevent the uneven dispersion caused by the adhesion of fillers to the internal mixer; the second kneading with the ram and increasing the speed can improve the shear performance, break the carbon black agglomerates, refine the particle size, and enhance the reinforcement effect; discharging the rubber at 155 - 160 °C can trigger the interfacial bonding between carbon black and mixture one, form a chemical cross-linking network, and increase the tensile strength to 15.6 MPa.

[0050] S3. Add sulfur, accelerator NS, super vulcanizing agent and binder RA to mixture two, and mix in the internal mixer at a ram pressure of 0.3 - 0.6 MPa and a rotor speed of 50 - 60 r / min for 20 - 30 s. After cleaning, reduce the rotor speed to 35 - 40 r / min, knead with the ram for 20 - 30 s, and continue to knead with the ram for 5 - 10 s after raising the ram until discharging the rubber at 95 - 100 °C, cutting it into sheets, and cooling it to obtain the rubber wheel compound.

[0051] A rotational speed of 50 - 60 r / min is a medium rotational speed, which can avoid the premature decomposition of fillers such as super vulcanizing agents due to excessive shear force, ensuring more uniform mixing of the fillers; the low rotational speed design can avoid the destruction of the structure of the super vulcanizing agent and promote the uniform distribution of the super vulcanizing agent; the low-temperature design can control the activation temperature of the super vulcanizing agent, avoid scorching (premature vulcanization), and at the same time protect the activity of the adhesive.

[0052] S4. According to the width of the recess on the outer edge of the metal cutting wheel, use a small extruder to extrude a rubber wheel film with a width of 5 - 6 cm and a thickness of 3 - 5 mm.

[0053] S5. As Figure 2 shown, use the primer and topcoat processes to coat the curing agent on the outer edge of the metal cutting wheel, let it stand for 1 - 2 hours, then place the metal cutting wheel into the vulcanization mold, wind the rubber wheel film around its outer edge, wind multiple turns until the vulcanization mold is filled, and then put it into the vulcanizer, vulcanize at a pressure of 40T and at 140 - 150 °C for 1.5 - 2.5 h to obtain a semi-finished rubber wheel.

[0054] Vulcanization at a pressure of 40T can eliminate the tiny air bubbles between the semi-finished rubber wheel and the metal cutting wheel and improve the crosslinking network density.

[0055] S6. After vulcanization, use a carving knife to carve a groove with a depth of 4 - 6 mm on the outer ring of the semi-finished rubber wheel to obtain a finished rubber wheel.

[0056] The rubber wheel produced through the above steps has a service life of at least 6 months and can be completed in as fast as 6 hours, greatly reducing the complexity of equipment use.

[0057] Examples and comparative examples of the rubber wheel rubber compound of this application are as follows:

[0058]

[0059]

[0060] The test results of the rubber wheel rubber compound after vulcanization are as follows:

[0061]

[0062]

[0063] The test results of the rubber wheel rubber compound after aging at 100 °C for 72 h are as follows:

[0064]

[0065] The optimal example of the present invention is Example 1.

[0066] Compared with Example 1, in Example 2, when the weight parts of other components are the same, the weight parts of the super vulcanizing agent and accelerator NS are changed, so that Tanδ@60℃ after vulcanization in Example 2 is higher than that in Example 1, that is, the heat generation of Example 2 is higher than that of Example 1, thus accelerating the thermal-oxidative aging and reducing the service life of the rubber wheel. The above conclusion can also be drawn from the fact that the aging coefficient of Example 1 after aging is 0.526, higher than that of Example 2 which is 0.488; the DIN abrasion index of Example 1 after aging is 290%, higher than 285% of Example 2, indicating that the abrasion performance of Example 1 is better.

[0067] From the comparison data of the above Example 1 and Comparative Examples 1-4, it can be seen that using liquid cis-butadiene rubber to equally replace the environmentally friendly rubber plasticizer, using emulsion polymerized styrene-butadiene rubber SBR 1502 to equally replace 20# standard rubber, using a super vulcanizing agent to replace the ordinary vulcanizing agent, and at the same time increasing the accelerator content can significantly improve the abrasion performance of the rubber wheel compound, especially the abrasion performance after aging can be improved by more than 80%, and the modulus at a specified elongation, aging resistance and low heat generation performance are all improved.

[0068] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "left", "right", "upper", "lower", "top", "bottom", "front", "rear", "inner", "outer", "back", "middle", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0069] However, the above are only specific embodiments of the present invention, and the scope of implementation of the present invention cannot be limited thereby. Therefore, the replacement of equivalent components or equivalent changes and modifications made according to the scope of protection of the present invention patent should still fall within the scope covered by the claims of the present invention.

Claims

1. A rubber wheel for a tire cutting machine, characterized in that, It comprises the following components in parts by weight: 0 - 50 parts of cis-butadiene rubber, 50 - 100 parts of emulsion-polymerized styrene-butadiene rubber SBR 1502, 3 - 5 parts of zinc oxide, 1 - 2 parts of stearic acid, 50 - 70 parts of carbon black, 0.5 - 2.0 parts of high-content antioxidant, 2 - 3 parts of tackifying resin, 0 - 15 parts of liquid cis-butadiene rubber, 0 - 1 part of sulfur, 1.5 - 5 parts of accelerator NS, 2.5 - 5 parts of super vulcanizing agent, 0 - 3 parts of resorcinol formaldehyde resin, 0 - 3 parts of adhesive; The super vulcanizing agent is a long-chain molecule with a sulfur content of 31% - 33%, and its molecular structure is: wherein, X is 2 - 6, n is 3 - 8, R1 is an alkyl chain with C2 - C20, and R2 is an alkyl chain with C2 - C8.

2. The rubber wheel for a tire cutting machine according to claim 1, wherein, The emulsion-polymerized styrene-butadiene rubber SBR1502 is SBR 1502 produced by low-temperature emulsion polymerization using styrene and butadiene as monomers; the liquid cis-butadiene rubber is a liquid butadiene rubber with a kinematic viscosity of 2.7 - 3.3 mPa·s at 20°C.

3. A rubber wheel for a tire cutting machine according to claim 1, characterized in that, The cis-butadiene rubber is nickel-based cis-butadiene BR9000; the carbon black is N115, N121, N220, N234 or a low heat build-up non-standard carbon black with a nitrogen adsorption specific surface area 8-10 values higher than the iodine adsorption value; the high-content antioxidant is antioxidant STMQ with a total content of dimer, trimer and tetramer greater than 70%; the tackifying resin is an octylphenol formaldehyde resin; the accelerator NS is N-tert-butyl-2-benzothiazole sulfenamide, and the molecular formula is C 11 H 14 N2S.

4. A rubber wheel for a tire cutting machine according to claim 1, characterized in that, The resorcinol formaldehyde resin is a condensation product obtained by the reaction of resorcinol and formaldehyde, and its molecular formula is C6H6O2·CH2O.

5. A rubber wheel for a tire cutting machine according to claim 1, wherein, The adhesive is composed of hexamethoxymethylmelamine and an inorganic carrier, the content of hexamethoxymethylmelamine is 65%, and the inorganic carrier is ordinary white carbon black or highly dispersed white carbon black.

6. A preparation method of a rubber wheel for a tire cutting machine, characterized in that, It includes the following steps: S1. Press the cis-butadiene rubber and the emulsion-polymerized styrene-butadiene rubber SBR 1502 with a rotor speed of 65 - 80 r / min in a Banbury mixer for 25 - 30 s to obtain mixture one; S2. Add carbon black, zinc oxide, stearic acid, high-content antioxidant, liquid cis-butadiene rubber, tackifying resin and resorcinol formaldehyde resin to mixture one. The rotor speed of the Banbury mixer first decreases and then increases. After heating, mixture two is obtained, and then the rubber is discharged, sheeted and cooled; S3. Add sulfur, accelerator NS, super vulcanizing agent and adhesive to mixture two. After the rotor speed of the Banbury mixer is reduced at low temperature, the rubber is discharged, sheeted and cooled to obtain the rubber wheel stock. After the rubber wheel stock is extruded, a rubber wheel sheet is obtained; S4. Place the metal cutting wheel coated with a curing agent into a vulcanization mold, wind the rubber wheel sheet around its outer edge and put it into a vulcanizer for vulcanization to obtain a semi-finished rubber wheel; S5. After vulcanization, grooves are engraved on the outer ring of the semi-finished rubber wheel to obtain the finished rubber wheel.

7. The preparation method of a rubber wheel for a tire cutting machine according to claim 6, characterized in that, In S2, the Banbury mixer presses for 25 - 30 s, reduces the rotor speed to 40 - 50 r / min, sweeps after that and then presses for 25 - 30 s again. After lifting the pressure weight, the rotor speed is increased to 50 - 55 r / min, and the rubber is discharged at 155 - 160°C.

8. The preparation method of a rubber wheel for a tire cutting machine according to claim 6, characterized in that, In S3, the Banbury mixer presses for 20 - 30 s and then sweeps. The rotor speed is reduced from 50 - 60 r / min to 35 - 40 r / min. After pressing for 20 - 30 s, the pressure weight is lifted for 5 - 10 s, and then the rubber is discharged at 95 - 100°C.

9. The preparation method of a rubber wheel for a tire cutting machine according to claim 6, characterized in that, In S4, the rubber wheel stock is vulcanized in a vulcanizer at a pressure of 40 T and at 140 - 150°C for 1.5 - 2.5 h to obtain a semi-finished rubber wheel.

10. The preparation method of a rubber wheel for a tire cutting machine according to claim 1, characterized in that, The pressure of the pressure weight of the Banbury mixer is 0.3 - 0.6 MPa.

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