CN110105636B - Preparation method of self-repairing tread rubber - Google Patents
Preparation method of self-repairing tread rubber Download PDFInfo
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- CN110105636B CN110105636B CN201910491721.XA CN201910491721A CN110105636B CN 110105636 B CN110105636 B CN 110105636B CN 201910491721 A CN201910491721 A CN 201910491721A CN 110105636 B CN110105636 B CN 110105636B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
- B60C1/00—Tyres characterised by the chemical composition or the physical arrangement or mixture of the composition
- B60C1/0016—Compositions of the tread
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L7/00—Compositions of natural rubber
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
- C08K3/20—Oxides; Hydroxides
- C08K3/22—Oxides; Hydroxides of metals
- C08K2003/2296—Oxides; Hydroxides of metals of zinc
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2205/00—Polymer mixtures characterised by other features
- C08L2205/02—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group
- C08L2205/025—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2205/00—Polymer mixtures characterised by other features
- C08L2205/03—Polymer mixtures characterised by other features containing three or more polymers in a blend
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2205/00—Polymer mixtures characterised by other features
- C08L2205/03—Polymer mixtures characterised by other features containing three or more polymers in a blend
- C08L2205/035—Polymer mixtures characterised by other features containing three or more polymers in a blend containing four or more polymers in a blend
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2205/00—Polymer mixtures characterised by other features
- C08L2205/14—Polymer mixtures characterised by other features containing polymeric additives characterised by shape
- C08L2205/16—Fibres; Fibrils
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- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Processes Of Treating Macromolecular Substances (AREA)
Abstract
The invention relates to a self-repairing tread rubber and a preparation method thereof, belonging to the technical field of rubber tires. The preparation method of the self-repairing tread rubber comprises the steps of pre-burying polyurethane with a side chain containing cyclopentadiene groups in hollow short fibers, pre-dispersing the polyurethane in natural rubber, adding the pre-dispersed polyurethane and catalyst organotin into a tread formula together, and mixing to obtain the tread rubber with a self-repairing function. The method is simple to operate, the existing mixing process in a workshop is not required to be changed, when the cracks generated in the running process of the tire extend to the surface of the hollow short fibers to break the fibers, the self-repairing polyurethane is released, the self-repairing polyurethane reacts under the action of the catalyst organic tin, the function of repairing the cracks is realized, and the safe running of the tire is ensured.
Description
Technical Field
The invention relates to a self-repairing tread rubber and a preparation method thereof, belonging to the technical field of rubber tires.
Background
With the rapid development of the automobile industry, the safety performance requirements for tires are gradually increased. Tires are primarily made of elastomeric materials and are often subjected to environmental or applied shear stresses during driving, resulting in unpredictable damage and structural failure. The service life of the material can be effectively prolonged and the use safety can be improved through the self-repairing technology. The self-repairing function is introduced into the polymer material, so that the material can be automatically repaired after damage is generated inside the material, and the structural material with longer service life, more reliable performance and more economical efficiency is obtained.
The inner part of a common automatic repair tire is provided with a layer of special coating rubber material. When the tire is punctured, the inner viscous material can wrap the punctured object to prevent air leakage, and when the punctured object is pulled out, the rubber material can fill the formed gap instantly, so that the function of automatic repair is realized. How to prepare the tread rubber with the self-repairing function is still an unsolved problem.
Disclosure of Invention
The invention aims to overcome the defects in the prior art and provides a preparation method of a self-repairing tread rubber. According to the invention, polyurethane with a self-repairing function and a side chain containing cyclopentadiene groups is filled in the hollow short fibers and added into the tire tread formula for mixing, the operation is simple, the existing mixing process in a workshop is not required to be changed, when cracks generated in the running process of the tire extend to the surface of the hollow short fibers to break the fibers, the self-repairing polyurethane is released, and the self-repairing polyurethane reacts under the action of the catalyst organic tin, so that the function of repairing the cracks is realized, and the safe running of the tire is ensured.
In order to solve the technical problems, the invention adopts the technical scheme that: the preparation method of the self-repairing tread rubber is characterized by comprising the following steps of:
a preparation method of self-repairing tread rubber comprises the following steps:
a) dissolving polyurethane with a side chain containing cyclopentadiene groups in tetrahydrofuran, adding hollow short fibers soaked with ethanol in advance, filling the polyurethane with the side chain containing cyclopentadiene groups in the hollow short fibers under an ultrasonic condition, filtering, and drying in a vacuum state to obtain the hollow short fiber self-repairing material, wherein the mass ratio of the polyurethane with the side chain containing cyclopentadiene groups to the hollow short fibers is 1 (0.5-3);
b) mixing the hollow short fiber self-repairing material and natural rubber on an open mill to obtain a hollow fiber self-repairing material rubber compound;
c) mixing 20-100 parts by weight of hollow short fiber self-repairing material rubber compound with 0-80 parts by weight of natural rubber, 0-20 parts by weight of butadiene rubber, 40-50 parts by weight of carbon black, 1-3 parts by weight of zinc oxide, 1-3 parts by weight of stearic acid and 2-4 parts by weight of an anti-aging agent in an internal mixer to obtain master batch;
d) and mixing the master batch, 1-3 parts of catalyst organotin, 2-5 parts of accelerator, 3-7 parts of sulfur and 0.1-0.3 part of scorch retarder in an internal mixer to obtain the self-repairing tread rubber.
The length of the hollow short fiber in the step a) is 1-6 mm.
The hollow short fiber in the step a) is one or more of polyester hollow fiber, polyvinylidene fluoride hollow fiber, polyamide hollow fiber, cellulose hollow fiber, polyimide hollow fiber, polypropylene hollow fiber, polyacrylonitrile hollow fiber, polyurethane hollow fiber, polytetrafluoroethylene hollow fiber and polyether sulfone hollow fiber.
In the step a), the ultrasonic frequency is 50-100 kHZ, and the ultrasonic time is 10-30 min.
The ratio of the hollow fiber self-repairing material to the natural rubber in the step b) is 1: 70-1: 40.
In the step c), the anti-aging agent is one or two of an anti-aging agent RD and an anti-aging agent 4020.
In step c), the carbon black is one or more of N134, N115, N234, N326, N330, N375 and N660.
The accelerant in the step d) is one or more of NS, CZ, DZ, NOBS and DM.
Compared with the prior art, the invention has the following advantages:
the polyurethane with the self-repairing function and the side chain containing the cyclopentadiene group is filled in the hollow short fibers and added into the tire tread formula for mixing, the operation is simple, and the existing mixing process in a workshop is not required to be changed. The catalyst organotin is a polyurethane catalyst with a side chain containing cyclopentadiene groups, is favorable for the reaction of a polyurethane side group, and is added in a final refining stage so as to be favorable for ensuring the activity of the catalyst; the hollow short fibers can store polyurethane self-repairing materials, when cracks generated in the running process of the tire extend to the surfaces of the hollow short fibers to break the fibers, the hollow short fibers release the self-repairing polyurethane, the self-repairing polyurethane reacts under the action of the catalyst, the function of repairing the cracks is achieved, and the safe running of the tire is guaranteed.
The technical solution of the present invention is further illustrated by the following specific examples.
Detailed Description
Example 1
A preparation method of self-repairing tread rubber comprises the following steps:
a) dissolving polyurethane with a side chain containing cyclopentadiene groups in tetrahydrofuran to prepare a solution with the concentration of 500g/L, adding polyester hollow short fibers soaked with ethanol in advance, carrying out ultrasonic treatment for 20 min under the ultrasonic condition of 50kHZ to ensure that the polyurethane with the side chain containing cyclopentadiene groups is filled in the hollow short fibers, filtering, and drying in a vacuum state to obtain the hollow short fiber self-repairing material, wherein the mass ratio of the polyurethane with the side chain containing cyclopentadiene groups to the hollow short fibers is 1: 0.5;
b) mixing 10 parts of hollow short fiber self-repairing material and 400 parts of natural rubber on an open mill, wherein the roll temperature of the open mill is 70 ℃, the roll distance is 1.2 mm, and the rotating speed is 45 revolutions per minute to obtain hollow short fiber self-repairing material rubber compound;
c) mixing 50 parts of hollow short fiber self-repairing material rubber compound with 30 parts of natural rubber, 20 parts of butadiene rubber, 40 parts of carbon black, 3 parts of zinc oxide, 2 parts of stearic acid and 3 parts of anti-aging agent in an internal mixer, wherein the rotating speed of a rotor of the internal mixer is 40 revolutions per minute, the upper ram pressure is 0.4MPa, the rubber mixing time is 60 seconds, and the rubber discharge temperature is 155 ℃, so as to obtain master batch;
d) mixing master batch, 2 parts of catalyst organotin, 5 parts of accelerator, 3 parts of sulfur and 0.1 part of scorch retarder in an internal mixer, wherein the rotating speed of a rotor of the internal mixer is 30 revolutions per minute, the top plug pressure is 0.4MPa, the mixing time is 50 seconds, and the rubber discharge temperature is 105 ℃ to obtain the self-repairing tread rubber.
Example 2
A preparation method of self-repairing tread rubber comprises the following steps:
a) dissolving polyurethane with a side chain containing cyclopentadiene groups in tetrahydrofuran to prepare a solution with the concentration of 500g/L, adding polyamide hollow short fibers soaked with ethanol in advance, carrying out ultrasonic treatment for 10 min under the ultrasonic condition of 100kHZ to ensure that the polyurethane with the side chain containing cyclopentadiene groups is filled in the hollow short fibers, filtering, and drying in a vacuum state to obtain the hollow short fiber self-repairing material, wherein the mass ratio of the polyurethane with the side chain containing cyclopentadiene groups to the hollow short fibers is 1: 1;
b) mixing 10 parts of hollow short fiber self-repairing material and 500 parts of natural rubber on an open mill, wherein the roll temperature of the open mill is 70 ℃, the roll distance is 1.2 mm, and the rotating speed is 45 revolutions per minute to obtain hollow short fiber self-repairing material rubber compound;
c) mixing 100 parts of hollow short fiber self-repairing material rubber compound, 45 parts of carbon black, 1 part of zinc oxide, 3 parts of stearic acid and 4 parts of anti-aging agent in an internal mixer, wherein the rotating speed of a rotor of the internal mixer is 40 revolutions per minute, the upper ram pressure is 0.4MPa, the rubber mixing time is 60 seconds, and the rubber discharge temperature is 155 ℃, so as to obtain master batch;
d) mixing master batch, 1 part of catalyst organotin, 3 parts of accelerator, 4 parts of sulfur and 0.2 part of scorch retarder in an internal mixer, wherein the rotating speed of a rotor of the internal mixer is 30 revolutions per minute, the top plug pressure is 0.4MPa, the mixing time is 50 seconds, and the rubber discharge temperature is 105 ℃ to obtain the self-repairing tread rubber.
Example 3
A preparation method of self-repairing tread rubber comprises the following steps:
a) dissolving polyurethane with a side chain containing cyclopentadiene groups in tetrahydrofuran to prepare a solution with the concentration of 500g/L, adding polyimide hollow short fibers soaked with ethanol in advance, carrying out ultrasonic treatment for 30 min under the ultrasonic condition of 70 kHZ to ensure that the polyurethane with the side chain containing cyclopentadiene groups is filled in the hollow short fibers, filtering, and drying in a vacuum state to obtain the hollow short fiber self-repairing material, wherein the mass ratio of the polyurethane with the side chain containing cyclopentadiene groups to the hollow short fibers is 1: 3;
b) mixing 10 parts of hollow short fiber self-repairing material and 700 parts of natural rubber on an open mill, wherein the roll temperature of the open mill is 70 ℃, the roll distance is 1.2 mm, and the rotating speed is 45 revolutions per minute to obtain hollow short fiber self-repairing material rubber compound;
c) mixing 20 parts of hollow short fiber self-repairing material rubber compound with 70 parts of natural rubber, 10 parts of butadiene rubber, 50 parts of carbon black, 2 parts of zinc oxide, 1 part of stearic acid and 2 parts of anti-aging agent in an internal mixer, wherein the rotating speed of a rotor of the internal mixer is 40 revolutions per minute, the upper ram pressure is 0.4MPa, the rubber mixing time is 60 seconds, and the rubber discharge temperature is 155 ℃, so as to obtain master batch;
d) mixing master batch, 3 parts of catalyst organotin, 2 parts of accelerator, 7 parts of sulfur and 0.3 part of scorch retarder in an internal mixer, wherein the rotating speed of a rotor of the internal mixer is 30 revolutions per minute, the top plug pressure is 0.4MPa, the mixing time is 50 seconds, and the rubber discharge temperature is 105 ℃ to obtain the self-repairing tread rubber.
In the embodiments 1 to 3 of the invention, polyurethane with a self-repairing function and a side chain containing cyclopentadiene groups is filled in hollow short fibers and added into a tire tread formula for mixing, and rubber mixing processes all adopt common mixing processes in workshops, so that the operation is simple, and the existing mixing process in the workshops is not required to be changed.
When the tire containing the self-repairing tread rubber runs, the tire can keep normal pressure to continue running for more than 2 km after passing through a nail with the diameter not more than 3 mm, and the tire without the self-repairing function directly has air leakage.
The above-described embodiments illustrate the present invention in detail. It should be understood, however, that the foregoing description is only exemplary of the present invention and is not intended to limit the invention. Any modification, addition, or equivalent substitution made within the scope of the principle of the present invention should be included in the scope of the present invention.
Claims (7)
1. The preparation method of the self-repairing tread rubber is characterized by comprising the following steps:
a) dissolving polyurethane with a side chain containing cyclopentadiene groups in tetrahydrofuran, adding hollow short fibers soaked with ethanol in advance, filling the polyurethane with the side chain containing cyclopentadiene groups in the hollow short fibers under an ultrasonic condition, filtering, and drying in a vacuum state to obtain the hollow short fiber self-repairing material, wherein the mass ratio of the polyurethane with the side chain containing cyclopentadiene groups to the hollow short fibers is 1 (0.5-3);
b) mixing the hollow short fiber self-repairing material and natural rubber on an open mill to obtain a hollow fiber self-repairing material rubber compound;
c) mixing 20-100 parts by weight of hollow short fiber self-repairing material rubber compound with 0-80 parts by weight of natural rubber, 0-20 parts by weight of butadiene rubber, 40-50 parts by weight of carbon black, 1-3 parts by weight of zinc oxide, 1-3 parts by weight of stearic acid and 2-4 parts by weight of an anti-aging agent in an internal mixer to obtain master batch;
d) mixing the master batch, 1-3 parts of catalyst organotin, 2-5 parts of accelerator, 3-7 parts of sulfur and 0.1-0.3 part of scorch retarder in an internal mixer to obtain self-repairing tread rubber;
the hollow short fiber in the step a) is one or more of polyester hollow fiber, polyvinylidene fluoride hollow fiber, polyamide hollow fiber, cellulose hollow fiber, polyimide hollow fiber, polypropylene hollow fiber, polyacrylonitrile hollow fiber, polyurethane hollow fiber, polytetrafluoroethylene hollow fiber and polyether sulfone hollow fiber.
2. The preparation method of the self-repairing tread rubber according to claim 1, wherein the length of the hollow short fiber in the step a) is 1-6 mm.
3. The preparation method of the self-repairing tread rubber according to claim 1, wherein the ultrasonic frequency in the step a) is 50-100 kHz, and the ultrasonic time is 10-30 min.
4. The preparation method of the self-repairing tread rubber of claim 1, wherein the ratio of the hollow fiber self-repairing material to the natural rubber in the step b) is 1: 70-1: 40.
5. The preparation method of the self-repairing tread rubber according to claim 1, wherein the antioxidant in the step c) is one or two of antioxidant RD and antioxidant 4020.
6. The method of preparing a self-repairing tread band of claim 1, wherein the carbon black in step c) is one or more of N134, N115, N234, N326, N330, N375, N660.
7. The method for preparing the self-repairing tread rubber according to claim 1, wherein the accelerator in step d) is one or more of NS, CZ, DZ, NOBS and DM.
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| CN112277534B (en) * | 2020-10-19 | 2022-11-25 | 山东省三利轮胎制造有限公司 | Self-repairing self-chain-forming antiskid tire |
| CN113185934B (en) * | 2021-05-10 | 2023-03-17 | 四川远星橡胶有限责任公司 | Self-repairing adhesive composition and preparation method and use method thereof |
| CN113563562B (en) * | 2021-08-23 | 2022-05-13 | 无锡安睿驰科技有限公司 | Disc-type self-repairing safety tire rubber material and preparation method thereof |
| CN115537150B (en) * | 2022-10-28 | 2023-07-07 | 东莞叁壹盛世科技有限公司 | Self-repairing tire inner coating sealing sizing material and preparation method thereof |
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| US6174974B1 (en) * | 1996-07-05 | 2001-01-16 | Bayer Aktiengesellschaft | Method for producing thermoplastic elastomers |
| CN101215407B (en) * | 2008-01-18 | 2011-02-09 | 中山大学 | High temperature self-restoring fibre enhancement epoxy composite material and preparation method thereof |
| CN102492174A (en) * | 2011-11-30 | 2012-06-13 | 哈尔滨工业大学 | Urea resin wrapped dicyclopentadiene nanometer microcapsule, and synthetic method and application thereof |
| CN103265736B (en) * | 2013-05-15 | 2015-05-20 | 北京化工大学 | Preparation method of microcapsules for rubber material self-repair |
| CN105440692B (en) * | 2015-12-14 | 2018-06-22 | 华南理工大学 | A kind of microcapsule-type selfreparing silicone elastomer and preparation method thereof |
| CN109762413A (en) * | 2018-12-25 | 2019-05-17 | 广东青龙建筑工程有限公司 | Two-component self-healing polymers cement waterproof paint based on liquid-core optical fibre method and preparation method thereof |
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