Integrally vulcanized self-repairing safety tire

Abstract

The invention relates to the technical field of self-repairing tires, and discloses an integrally vulcanized self-repairing safety tire which sequentially comprises an isolating membrane, a self-repairing layer, an airtight layer, a transition layer, cord fabric, a steel wire layer, a nylon belted layer and tread rubber from inside to outside, the self-repairing rubber material comprises the following raw materials: 65-85 parts of a rubber matrix, 5-9 parts of tackifying resin, 7-12 parts of modified polyurethane, 2-6 parts of modified white carbon black, 2-3 parts of an anti-aging agent and 1-2 parts of an auxiliary agent, the self-repairing layer and the tire matrix are integrally vulcanized in the vulcanization process to realize compounding, a chemically crosslinked integral structure is formed, the bonding strength between layers of the tire is remarkably improved, and the service life of the tire is prolonged. A whole compact in structure and stable in interface is formed in the tire, the structural strength, durability and long-term use reliability of the tire are remarkably improved, the structural stability of the tire is guaranteed, and the driving requirements of vehicles on high-speed, heavy-load and complex road conditions can be met.

Description

Technical Field

[0001] This invention relates to the field of self-healing tire technology, specifically to an integrated vulcanized self-healing safety tire. Background Technology

[0002] With the rapid development of society and the economy, automobiles have become the mainstream means of transportation, and people's requirements for the safety and reliability of automobiles are constantly upgrading, especially the performance of tires, a core safety component. Traditional pneumatic tires are easily punctured by sharp objects such as nails and glass shards during driving, which can not only cause vehicles to break down midway and affect travel efficiency, but also lead to serious traffic accidents such as tire blowouts, posing a direct threat to the lives and property of drivers and passengers. Self-sealing tires, with their self-sealing materials and mechanisms, can automatically repair minor damage to the tire surface after a puncture, sealing themselves and allowing continued driving without additional repairs. This provides a new solution to this problem and has become an important direction for tire technology upgrades. They can effectively extend tire life, improve road driving safety, and have broad application prospects.

[0003] The vulcanization process is a core step in tire production, directly affecting tire structural strength, wear resistance, and service life. Current self-sealing tire production often employs a step-by-step process: first vulcanizing the tire body, then bonding it with the self-sealing layer. While simple, this process relies solely on a secondary adhesive bond, resulting in low interfacial strength. Under long-term dynamic loads, temperature changes, and fatigue, delamination and peeling easily occur, leading to self-healing failure. Furthermore, this process is inefficient. To achieve a tight bond between the self-sealing layer and the tire body and prevent later detachment and failure, an integrated vulcanization process is adopted. The self-sealing layer is pre-placed inside the tire and undergoes high-temperature, high-pressure vulcanization simultaneously with other tire components. However, during vulcanization, the self-sealing layer is in direct contact with the tire body, making it highly susceptible to adhesion due to molecular diffusion. This can lead to defects such as missing rubber and scratches on the tire's inner surface, while also compromising the structural integrity of the self-sealing layer, causing a decline in self-healing function and affecting airtightness and service life.

[0004] Therefore, there is an urgent need to develop a self-healing safety tire that is compatible with the integrated vulcanization process. By optimizing material properties and processing technology, a self-healing safety tire with excellent overall performance can be provided. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides an integrated vulcanized self-healing safety tire, which improves tire safety and service life, and solves the problem of easy delamination between the self-healing layer and the tire matrix in self-healing tires.

[0006] To achieve the above objectives, the present invention discloses an integrated vulcanized self-healing safety tire, which, from the inside out, comprises a separator, a self-healing layer, an airtight layer, a transition layer, a cord fabric, a steel wire layer, a nylon belt layer, and a tread compound.

[0007] The self-healing layer is composed of a self-healing adhesive. By weight, the self-healing compound comprises the following raw materials: 65-85 parts of rubber matrix, 5-9 parts of tackifying resin, 7-12 parts of modified polyurethane, 2-6 parts of modified silica, 2-3 parts of antioxidant, and 1-2 parts of additives.

[0008] Preferably, the airtight layer, cord fabric, steel wire layer, nylon belt layer, and tread compound adopt a conventional radial tire matrix structure and are prepared according to existing tire matrix molding processes.

[0009] Preferably, the separator is a PET film coated with silicone oil.

[0010] Preferably, the transition layer is made of styrene-butadiene rubber compound and maleic anhydride-grafted styrene-butadiene rubber in a mass ratio of 100:3. Its function is to alleviate the performance differences between the self-healing layer, the airtight layer, and the cord fabric, enhance the bonding strength between the layers, and prevent delamination and debonding during the vulcanization process.

[0011] Preferably, in the self-healing rubber compound, the rubber matrix is ​​composed of natural rubber and butyl rubber in a mass ratio of 3:2; the tackifying resin is composed of terpene resin and hydrogenated C5 petroleum resin in a mass ratio of 6:1; the antioxidant is composed of antioxidant 4020 and antioxidant RD in a mass ratio of 2:1; and the additives are composed of sulfur vulcanizing agent, N-cyclohexyl-2-benzothiazole sulfenamide accelerator, and zinc stearate activator in a mass ratio of 2:3:10.

[0012] Preferably, the preparation method of the modified silica in the self-healing adhesive includes the following steps: ultrasonically dispersing silica in deionized water, and after uniform dispersion, adding γ-mercaptopropyltrimethoxysilane, wherein the mass ratio of silica, deionized water and γ-mercaptopropyltrimethoxysilane is 100:(1200-2000):(1-5), stirring and mixing, heating, adjusting the pH to 9-12 with ammonia water, reacting at 70-80℃ for 2-4 hours, after the reaction is completed, filtering, washing with anhydrous ethanol and deionized water, and drying at 60℃ for 12 hours to obtain modified silica.

[0013] Preferably, in the self-healing adhesive, the preparation method of the modified polyurethane includes the following steps: S1. Halloysite nanotubes were degassed under vacuum at 120℃ for 6 hours. After treatment, they were cooled to obtain pretreated halloysite nanotubes. The pretreated halloysite nanotubes were ultrasonically dispersed in toluene. After uniform dispersion, γ-glycidyl etheroxypropyltriethoxysilane was added. The mixture was heated and stirred under a nitrogen atmosphere to allow the reaction to proceed. After the reaction was completed, the mixture was filtered, washed with toluene and anhydrous ethanol, and dried at 60℃ for 12 hours to obtain epoxidized halloysite nanotubes. S2. Add epoxidized halloysite nanotubes to N,N-dimethylformamide, disperse evenly by ultrasonication, add 4,4'-diaminodiphenyl sulfone, stir and mix, heat to allow the reaction to occur, and after the reaction is complete, rotary evaporate to obtain aminated halloysite nanotubes. S3. Aminated halloysite nanotubes and isophorone diisocyanate were reacted at 80-90℃ for 1 h, then cooled to 75℃, polypropylene glycol 2000 was added, and the reaction was carried out for 2 h. 2,2-bis(hydroxymethyl)propionic acid was added, stirred and mixed, and reacted at 80-90℃ for 2 h. 1,4-Butanediol and trimethylolpropane were added, and the reaction was carried out for 2 h. After cooling, triethylamine was added, and the reaction was carried out at 30-40℃ for 30-40 min. Deionized water was added dropwise, and high-speed shear emulsification was performed. After standing, the mixture was vacuum dried at 50℃ for 24 h to obtain modified polyurethane.

[0014] Preferably, in S1, the mass ratio of pretreated halloysite nanotubes, toluene, and γ-glycidyl etheroxypropyltriethoxysilane is 100:(900-1200):(75-85), the reaction temperature is 110-120℃, and the reaction time is 12-15h.

[0015] Preferably, the mass ratio of N,N-dimethylformamide, halloysite nanotubes epoxidized and 4,4'-diaminodiphenyl sulfone in S2 is (1000-1200):100:(90-112), the reaction temperature is 90-105℃, and the reaction time is 5-8h.

[0016] Preferably, the mass ratio of amino-modified halloysite nanotubes, isophorone diisocyanate, polypropylene glycol 2000, 2,2-bis(hydroxymethyl)propionic acid, 1,4-butanediol, trimethylolpropane, and triethylamine in S3 is 100:(65-82):(280-350):(12-18):(8-12):(2.5-3.5):(10-16).

[0017] Preferably, the manufacturing process of the integrated vulcanized self-healing safety tire includes the following steps: Step 1: Mix the self-healing compound evenly on an internal mixer and a two-roll mill to obtain the self-healing layer; Step 2: Clean the tire forming drum thoroughly, removing surface dust and oil. On the tire forming drum, attach the release film with the release surface facing inward. On the outside of the release film, attach the self-healing layer, airtight layer, transition layer, cord fabric, steel wire layer, nylon belt layer, and tread rubber in sequence from the inside out. First, use a pressure roller to compact it, press it according to the outline of the tire crown, trim any excess rubber material, and make a green tire. Let the green tire stand for 1-2 hours. Step 3: Place the green tire in a dual-mold tire vulcanizing machine for vulcanization. After vulcanization, demold, trim, and cool to obtain an integrated vulcanized self-healing safety tire. When using pressure rollers, compact the tire from the center outwards and from the middle outwards in multiple directions to ensure tight adhesion between layers and no residual air.

[0018] Preferably, the preparation method of the self-healing layer in step one includes the following steps: adding the rubber matrix, antioxidant, zinc stearate, and modified silica into a mixer, mixing at 70-90℃ for 2-4 minutes, then adding the tackifying resin and modified polyurethane, and continuing to mix at 100-120℃ for 2-3 minutes. After discharging the masterbatch, wrapping it with rollers on a two-roll mill at a roller temperature of 50-60℃, then sequentially adding the accelerator N-cyclohexyl-2-benzothiazole sulfenamide and the vulcanizing agent sulfur, and performing two-roll milling at a temperature of 60-70℃ and a rotation speed of 25-35 r / min for 5-8 minutes. During the two-roll milling process, the mixture is repeatedly turned over and dispersed evenly. After that, the mixture is sheeted to obtain the self-healing layer.

[0019] Preferably, in step two, the bonding temperature is 50-60℃, the pressure roller pressure is 0.5-0.8MPa, the pressing pressure is 1.0-1.2MPa, and the pressing time is 5-8min.

[0020] Preferably, the vulcanization process in step three is carried out in a nitrogen atmosphere, with a vulcanization pressure of 1.8-2.2 MPa, a vulcanization temperature of 155-165°C, and a vulcanization time of 20-30 min.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) In this invention, the rubber matrix of the self-healing compound is a compound rubber. The natural rubber used has high elasticity and high cohesive energy, which can provide a physical basis for self-healing. Butyl rubber has high air tightness, which can reduce air leakage. Halloysite nanotubes are epoxidized and aminated to obtain aminated halloysite nanotubes, which are reacted with isophorone diisocyanate and polypropylene glycol 2000 to obtain modified polyurethane. The tubular structure of halloysite nanotubes in the modified polyurethane can achieve the reinforcement of the compound. After modification, it can be uniformly dispersed in the matrix, avoiding the local failure of self-healing performance caused by agglomeration. The intermolecular hydrogen bonds of polyurethane provide flexible reinforcement for self-healing. γ-mercaptopropyltrimethoxysilane is used to modify silica, which greatly improves the dispersibility in the rubber matrix, avoids the decline in mechanical properties of the compound caused by the agglomeration of unmodified silica, and effectively improves the mechanical strength of the self-healing compound. Simultaneously, mercapto groups are introduced onto the surface of silica, forming dynamic cross-links with the rubber matrix and modified polyurethane. This allows for rapid bonding of the damaged area through intermolecular forces after tire puncture. Furthermore, the introduced tackifying resin effectively enhances the interfacial adhesion of the rubber compound, making it easier to achieve a tighter bond at small punctures. The synergistic effect of the various raw materials in the self-healing layer improves the thermal stability and resistance to thermo-oxidative aging of the self-healing compound, ensuring that the temperature range of the self-healing layer matches that of the tire matrix. The self-healing layer can quickly repair minor damage caused by sharp objects during driving, preventing tire leaks in real time and fundamentally avoiding safety accidents such as tire blowouts and loss of vehicle control caused by leaks from small punctures. Moreover, the self-healing performance shows no significant degradation over long-term use, providing continuous safety protection.

[0022] (2) In this invention, the vulcanization process of the tire green tire is carried out in a nitrogen atmosphere, which avoids the oxidative degradation of the rubber compound during the vulcanization stage, ensures the uniformity of the crosslinking density of the rubber compound, and reduces the performance degradation caused by vulcanization oxidation. At the same time, there are no gaps between the tire layers, which avoids accelerated aging caused by local air retention. The aging resistance of the self-healing layer is consistent with that of the tire matrix, which not only extends the overall service life of the tire, but also ensures that the self-healing performance remains effective throughout the tire's entire life cycle and will not fail due to rubber compound aging.

[0023] (3) The integrated vulcanization process in this invention allows the self-healing layer and the tire matrix to be composited during the vulcanization process, forming a chemically cross-linked overall structure, rather than the traditional secondary bonding. This avoids interface weaknesses and delamination risks, simplifies the production process, and improves production efficiency. The integrated vulcanization process significantly improves the bonding strength between the tire layers, forming a dense and stable whole inside the tire, which significantly improves the tire's structural strength, durability, and long-term reliability. Under complex conditions such as vehicle bumps, repeated flexing, and temperature changes, there is no delamination or debonding, ensuring the structural stability of the tire and meeting the driving requirements of high-speed, heavy-load, and complex road conditions. Detailed Implementation

[0024] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0025] Example 1 A modified silica, the preparation method of which includes the following steps: Silica was ultrasonically dispersed in deionized water. After uniform dispersion, γ-mercaptopropyltrimethoxysilane was added, wherein the mass ratio of silica, deionized water and γ-mercaptopropyltrimethoxysilane was 100:1200:1. The mixture was stirred and heated, and the pH was adjusted to 9 with ammonia. The reaction was carried out at 70°C for 4 hours. After the reaction was completed, the mixture was filtered, washed with anhydrous ethanol and deionized water, and dried at 60°C for 12 hours to obtain modified silica.

[0026] Example 2 A modified silica, the preparation method of which includes the following steps: Silica was ultrasonically dispersed in deionized water. After uniform dispersion, γ-mercaptopropyltrimethoxysilane was added, wherein the mass ratio of silica, deionized water, and γ-mercaptopropyltrimethoxysilane was 100:1600:3. The mixture was stirred and heated, and the pH was adjusted to 10 with ammonia. The reaction was carried out at 75°C for 3 hours. After the reaction was completed, the mixture was filtered, washed with anhydrous ethanol and deionized water, and dried at 60°C for 12 hours to obtain modified silica.

[0027] Example 3 A modified silica, the preparation method of which includes the following steps: Silica was ultrasonically dispersed in deionized water. After uniform dispersion, γ-mercaptopropyltrimethoxysilane was added, wherein the mass ratio of silica, deionized water, and γ-mercaptopropyltrimethoxysilane was 100:2000:5. The mixture was stirred and heated, and the pH was adjusted to 12 with ammonia. The reaction was carried out at 80°C for 2 hours. After the reaction was completed, the mixture was filtered, washed with anhydrous ethanol and deionized water, and dried at 60°C for 12 hours to obtain modified silica.

[0028] Example 4 A modified polyurethane, the preparation method of which includes the following steps: S1. Halloysite nanotubes were degassed under vacuum at 120℃ for 6 hours. After treatment, they were cooled to obtain pretreated halloysite nanotubes. The pretreated halloysite nanotubes were ultrasonically dispersed in toluene. After uniform dispersion, γ-glycidyl etheroxypropyltriethoxysilane was added. The mass ratio of the added pretreated halloysite nanotubes, toluene, and γ-glycidyl etheroxypropyltriethoxysilane was 100:900:75. The mixture was heated and stirred under a nitrogen atmosphere to allow the reaction to occur. The reaction temperature was 110℃ and the reaction time was 15 hours. After the reaction was completed, the mixture was filtered, washed with toluene and anhydrous ethanol, and dried at 60℃ for 12 hours to obtain epoxidized halloysite nanotubes. S2. Add epoxidized halloysite nanotubes to N,N-dimethylformamide, disperse evenly by ultrasonication, and then add 4,4'-diaminodiphenyl sulfone. The mass ratio of N,N-dimethylformamide, epoxidized halloysite nanotubes, and 4,4'-diaminodiphenyl sulfone is 1000:100:90. Stir and mix, heat to allow the reaction to occur at 90℃ for 8 hours. After the reaction is complete, rotary evaporate to obtain aminated halloysite nanotubes. S3. Aminated halloysite nanotubes and isophorone diisocyanate were reacted at 80℃ for 1 h, then cooled to 75℃, polypropylene glycol 2000 was added, and the reaction was carried out for 2 h. 2,2-bis(hydroxymethyl)propionic acid was added, and the mixture was stirred and mixed. After reacting at 80℃ for 2 h, 1,4-butanediol and trimethylolpropane were added, and the reaction was carried out for 2 h. After cooling, triethylamine was added. The mass ratio of aminated halloysite nanotubes, isophorone diisocyanate, polypropylene glycol 2000, 2,2-bis(hydroxymethyl)propionic acid, 1,4-butanediol, trimethylolpropane, and triethylamine was 100:65:280:12:8:2.5:10. The mixture was reacted at 30℃ for 40 min, deionized water was added dropwise, and high-speed shear emulsification was performed. After standing, the mixture was vacuum dried at 50℃ for 24 h to obtain modified polyurethane.

[0029] Example 5 A modified polyurethane, the preparation method of which includes the following steps: S1. Halloysite nanotubes were degassed under vacuum at 120℃ for 6 hours. After treatment, they were cooled to obtain pretreated halloysite nanotubes. The pretreated halloysite nanotubes were ultrasonically dispersed in toluene. After uniform dispersion, γ-glycidyl etheroxypropyltriethoxysilane was added. The mass ratio of the added pretreated halloysite nanotubes, toluene, and γ-glycidyl etheroxypropyltriethoxysilane was 100:1050:80. The mixture was heated and stirred under a nitrogen atmosphere to allow the reaction to occur. The reaction temperature was 115℃ and the reaction time was 14 hours. After the reaction was completed, the mixture was filtered, washed with toluene and anhydrous ethanol, and dried at 60℃ for 12 hours to obtain epoxidized halloysite nanotubes. S2. Add epoxidized halloysite nanotubes to N,N-dimethylformamide, disperse evenly by ultrasonication, and then add 4,4'-diaminodiphenyl sulfone. The mass ratio of N,N-dimethylformamide, epoxidized halloysite nanotubes, and 4,4'-diaminodiphenyl sulfone is 1100:100:102. Stir and mix, heat to allow the reaction to occur at 95℃ for 6 hours. After the reaction is complete, rotary evaporate to obtain aminated halloysite nanotubes. S3. Aminated halloysite nanotubes and isophorone diisocyanate were reacted at 85℃ for 1 h, then cooled to 75℃, polypropylene glycol 2000 was added, and the reaction was carried out for 2 h. 2,2-bis(hydroxymethyl)propionic acid was added, and the mixture was stirred and mixed. After reacting at 85℃ for 2 h, 1,4-butanediol and trimethylolpropane were added, and the reaction was carried out for 2 h. After cooling, triethylamine was added. The mass ratio of aminated halloysite nanotubes, isophorone diisocyanate, polypropylene glycol 2000, 2,2-bis(hydroxymethyl)propionic acid, 1,4-butanediol, trimethylolpropane, and triethylamine was 100:75:320:15:10:3:14. The mixture was reacted at 35℃ for 35 min, deionized water was added dropwise, and high-speed shear emulsification was performed. After standing, the mixture was vacuum dried at 50℃ for 24 h to obtain modified polyurethane.

[0030] Example 6 A modified polyurethane, the preparation method of which includes the following steps: S1. Halloysite nanotubes were degassed under vacuum at 120℃ for 6 hours. After treatment, they were cooled to obtain pretreated halloysite nanotubes. The pretreated halloysite nanotubes were ultrasonically dispersed in toluene. After uniform dispersion, γ-glycidyl etheroxypropyltriethoxysilane was added. The mass ratio of the added pretreated halloysite nanotubes, toluene, and γ-glycidyl etheroxypropyltriethoxysilane was 100:1200:85. The mixture was heated and stirred under a nitrogen atmosphere to allow the reaction to occur. The reaction temperature was 120℃ and the reaction time was 12 hours. After the reaction was completed, the mixture was filtered, washed with toluene and anhydrous ethanol, and dried at 60℃ for 12 hours to obtain epoxidized halloysite nanotubes. S2. Add epoxidized halloysite nanotubes to N,N-dimethylformamide, disperse evenly by ultrasonication, and then add 4,4'-diaminodiphenyl sulfone. The mass ratio of N,N-dimethylformamide, epoxidized halloysite nanotubes, and 4,4'-diaminodiphenyl sulfone is 1200:100:112. Stir and mix, heat to allow the reaction to occur at 105℃ for 5 hours. After the reaction is complete, rotary evaporate to obtain aminated halloysite nanotubes. S3. Aminated halloysite nanotubes and isophorone diisocyanate were reacted at 90℃ for 1 h, then cooled to 75℃, polypropylene glycol 2000 was added, and the reaction was carried out for 2 h. 2,2-bis(hydroxymethyl)propionic acid was added, and the mixture was stirred and mixed. After reacting at 90℃ for 2 h, 1,4-butanediol and trimethylolpropane were added, and the reaction was carried out for 2 h. After cooling, triethylamine was added. The mass ratio of aminated halloysite nanotubes, isophorone diisocyanate, polypropylene glycol 2000, 2,2-bis(hydroxymethyl)propionic acid, 1,4-butanediol, trimethylolpropane, and triethylamine was 100:82:350:18:12:3.5:16. The mixture was reacted at 40℃ for 30 min, deionized water was added dropwise, and the mixture was emulsified by high-speed shearing. After standing, it was vacuum dried at 50℃ for 24 h to obtain modified polyurethane.

[0031] Example 7 A self-healing, integrated vulcanized safety tire, the manufacturing process of which includes the following steps: Step 1: Weigh the following raw materials for the repair compound by weight: 65 parts rubber matrix, 5 parts tackifying resin, 7 parts modified polyurethane, 2 parts modified silica, 2 parts antioxidant, and 1 part additives. The rubber matrix consists of natural rubber and butyl rubber in a 3:2 weight ratio; the tackifying resin consists of terpene resin and hydrogenated C5 petroleum resin in a 6:1 weight ratio; the antioxidant consists of antioxidant 4020 and antioxidant RD in a 2:1 weight ratio; and the additives consist of sulfur (curing agent), N-cyclohexyl-2-benzothiazole sulfenamide (accelerator), and active ingredients in a 2:3:10 weight ratio. The mixture consists of zinc stearate, rubber matrix, antioxidant, zinc stearate, and modified silica. These are added to a mixer and mixed at 70°C for 4 minutes. Then, tackifying resin and modified polyurethane are added, and the mixture is further mixed at 100°C for 3 minutes. After the masterbatch is discharged, it is rolled on a two-roll mill at a roller temperature of 50°C. Then, accelerator N-cyclohexyl-2-benzothiazole sulfenamide and vulcanizing agent sulfur are added in sequence. The two-roll mill is then rolled at 60°C and 25 r / min for 8 minutes. The two-roll mill is repeatedly turned over during the rolling process until it is evenly dispersed. Finally, the mixture is sheeted to obtain a self-healing layer. Step 2: Clean the tire forming drum thoroughly, removing surface dust and oil. On the tire forming drum, attach the release film with the release surface facing inward. On the outside of the release film, attach the self-healing layer, airtight layer, transition layer, cord fabric, steel wire layer, nylon belt layer, and tread rubber in sequence from the inside out. The bonding temperature is 50℃. First, use a pressure roller to compact it with a pressure of 0.5MPa. Press it according to the outline of the tire crown with a pressing pressure of 1.0MPa and a pressing time of 8 minutes. Trim off any excess rubber material to form the green tire. Let the green tire stand for 1 hour. Step 3: Place the green tire in a dual-mold tire vulcanizing machine for vulcanization. The vulcanization process is carried out in a nitrogen atmosphere. The vulcanization pressure is 1.8 MPa, the vulcanization temperature is 155℃, and the vulcanization time is 30 minutes. After the vulcanization process is completed, demold, trim, and cool to obtain an integrated vulcanized self-healing safety tire.

[0032] The preparation method of modified silica in this embodiment is completely the same as that in Example 1, and the preparation method of modified polyurethane is completely the same as that in Example 4.

[0033] Example 8 A self-healing, integrated vulcanized safety tire, the manufacturing process of which includes the following steps: Step 1: Weigh the following raw materials for the repair compound by weight: 75 parts rubber matrix, 7 parts tackifying resin, 10 parts modified polyurethane, 4 parts modified silica, 2.5 parts antioxidant, and 1.5 parts additives. The rubber matrix consists of natural rubber and butyl rubber in a 3:2 weight ratio; the tackifying resin consists of terpene resin and hydrogenated C5 petroleum resin in a 6:1 weight ratio; the antioxidant consists of antioxidant 4020 and antioxidant RD in a 2:1 weight ratio; and the additives consist of sulfur vulcanizing agent, N-cyclohexyl-2-benzothiazole sulfenamide accelerator, and active ingredient in a 2:3:10 weight ratio. The product is composed of zinc stearate as a modifier. The rubber matrix, antioxidant, zinc stearate, and modified silica are added to a mixer and mixed at 80°C for 3 minutes. Then, tackifying resin and modified polyurethane are added, and the mixture is mixed at 110°C for 2.5 minutes. After the masterbatch is discharged, it is rolled on a two-roll mill at a roller temperature of 55°C. Then, accelerator N-cyclohexyl-2-benzothiazole sulfenamide and vulcanizing agent sulfur are added in sequence. The two-roll mill is then rolled at 65°C and 30 r / min for 7 minutes. During the rolling process, the mixture is repeatedly turned over and evenly dispersed. The product is then sheeted to obtain a self-healing layer. Step 2: Clean the tire forming drum thoroughly, removing surface dust and oil. On the tire forming drum, attach the release film with the release surface facing inward. On the outside of the release film, attach the self-healing layer, airtight layer, transition layer, cord fabric, steel wire layer, nylon belt layer, and tread rubber in sequence from the inside out. The bonding temperature is 55℃. First, use a pressure roller to compact it with a pressure of 0.7MPa. Press it according to the outline of the tire crown with a pressing pressure of 1.1MPa and a pressing time of 6 minutes. Trim off any excess rubber material to form the green tire. Let the green tire stand for 1.5 hours. Step 3: Place the green tire in a dual-mold tire vulcanizing machine for vulcanization. The vulcanization process is carried out in a nitrogen atmosphere. The vulcanization pressure is 2.0 MPa, the vulcanization temperature is 160℃, and the vulcanization time is 25 minutes. After the vulcanization process is completed, demold, trim, and cool to obtain an integrated vulcanized self-healing safety tire.

[0034] The preparation method of modified silica in this embodiment is completely the same as that in Example 2, and the preparation method of modified polyurethane is completely the same as that in Example 5.

[0035] Example 9 A self-healing, integrated vulcanized safety tire, the manufacturing process of which includes the following steps: Step 1: Weigh the following raw materials for the repair compound by weight: 85 parts rubber matrix, 9 parts tackifying resin, 12 parts modified polyurethane, 6 parts modified silica, 3 parts antioxidant, and 2 parts additives. The rubber matrix consists of natural rubber and butyl rubber in a 3:2 weight ratio; the tackifying resin consists of terpene resin and hydrogenated C5 petroleum resin in a 6:1 weight ratio; the antioxidant consists of antioxidant 4020 and antioxidant RD in a 2:1 weight ratio; and the additives consist of sulfur (curing agent), N-cyclohexyl-2-benzothiazole sulfenamide (accelerator), and active ingredients in a 2:3:10 weight ratio. The mixture consists of zinc stearate, rubber matrix, antioxidant, zinc stearate, and modified silica. These are added to a mixer and mixed at 90°C for 2 minutes. Then, tackifying resin and modified polyurethane are added, and the mixture is further mixed at 120°C for 2 minutes. After discharging the masterbatch, it is rolled on a two-roll mill at 60°C. Then, accelerator N-cyclohexyl-2-benzothiazole sulfenamide and vulcanizing agent sulfur are added sequentially. The two-roll mill is then rolled at 70°C and 35 r / min for 5 minutes. During the rolling process, the mixture is repeatedly turned over until it is evenly dispersed. Finally, the mixture is sheeted to obtain a self-healing layer. Step 2: Clean the tire forming drum thoroughly, removing surface dust and oil. On the tire forming drum, attach the release film with the release surface facing inward. On the outside of the release film, attach the self-healing layer, airtight layer, transition layer, cord fabric, steel wire layer, nylon belt layer, and tread rubber in sequence from the inside out. The bonding temperature is 60℃. First, use a pressure roller to compact it with a pressure of 0.8MPa. Press it according to the outline of the tire crown with a pressing pressure of 1.2MPa and a pressing time of 5 minutes. Trim off any excess rubber material to form the green tire. Let the green tire stand for 2 hours. Step 3: Place the green tire in a dual-mold tire vulcanizing machine for vulcanization. The vulcanization process is carried out in a nitrogen atmosphere. The vulcanization pressure is 2.2 MPa, the vulcanization temperature is 165℃, and the vulcanization time is 20 minutes. After the vulcanization process is completed, demold, trim, and cool to obtain an integrated vulcanized self-healing safety tire.

[0036] The preparation method of modified silica in this embodiment is completely the same as that in Example 3, and the preparation method of modified polyurethane is completely the same as that in Example 6.

[0037] Comparative Example 1 A self-healing, integrated vulcanized safety tire, the manufacturing process of which includes the following steps: Compared with the preparation process of the integrated vulcanized self-healing safety tire in Example 8, the difference is that the modified silica in the self-healing rubber compound is replaced with silica in an equal amount, while the other preparation processes are completely the same as in Example 8.

[0038] Comparative Example 2 A self-healing, integrated vulcanized safety tire, the manufacturing process of which includes the following steps: Compared with the preparation process of the integrated vulcanized self-healing safety tire in Example 8, the difference is that the modified polyurethane in the self-healing rubber compound is replaced in equal amounts with a mixture of halloysite nanotubes and polyurethane in a mass ratio of 1:4. The other preparation processes are completely consistent with those in Example 8.

[0039] Comparative Example 3 A self-healing, integrated vulcanized safety tire, the manufacturing process of which includes the following steps: Compared with the preparation process of the integrated vulcanized self-healing safety tire in Example 8, the difference is that the tire was not left to stand after it was made and the vulcanization process was not carried out in a nitrogen atmosphere. The other preparation processes are completely the same as those in Example 8.

[0040] The integrated vulcanized self-healing safety tires prepared in Examples 7-9 and Comparative Examples 1-3 were used as samples for corresponding tests. The test methods and results are shown below: (1) Mechanical properties and self-healing test: The tensile properties of the sample were tested using a Z005 universal electronic tensile tester. The test standard was in accordance with GB / T 528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber", with a temperature of 25℃, a load of 1000N, and a tensile rate of 500mm / min. Self-healing process: Make a 1mm deep and 10mm long incision at the center of the specimen (simulating local damage), place it in an environment of 23℃ and 50% humidity for 24 hours, repair it in a free state, test the tensile strength and elongation at break of the repaired specimen according to the same test standard, and calculate the retention rate of tensile strength and elongation at break after repair. (2) Peel strength test: The test standard refers to GB / T 2790-1995 "Test method for 180° peel strength of adhesives, flexible materials to rigid materials", the sample size is 15mm (width) × 100mm (length), the tensile speed is 50mm / min, and the interlayer peel strength is tested; Each test group was tested three times, and the average value was taken. The test results are shown in Table 1: Table 1

[0041] As can be seen from the test results in Table 1, the samples corresponding to Examples 7-9 have excellent mechanical properties. After scratch repair, the tensile strength and elongation at break still maintain a good retention rate, indicating that the corresponding samples still possess excellent mechanical properties. In Comparative Example 1, the silica is prone to agglomeration and has poor compatibility. In Comparative Example 2, the halloysite nanotubes were not modified, making them prone to agglomeration and reducing tensile strength. This resulted in a significant decrease in flow repair and self-healing capabilities after puncture, leading to poorer mechanical properties and low peel strength. In Comparative Example 3, the samples were not allowed to stand before vulcanization, and the internal stress was not released. Vulcanization in air caused interfacial oxidation, generating a weak boundary layer and resulting in poor overall performance.

[0042] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. A self-healing, integrated vulcanizing safety tire, characterized in that: From the inside out, it includes the following layers: separator, self-healing layer, airtight layer, transition layer, cord fabric, steel wire layer, nylon belt layer, and tread rubber. The self-healing layer is composed of a self-healing adhesive. By weight, the self-healing compound comprises the following raw materials: 65-85 parts of rubber matrix, 5-9 parts of tackifying resin, 7-12 parts of modified polyurethane, 2-6 parts of modified silica, 2-3 parts of antioxidant, and 1-2 parts of additives.

2. The integrated vulcanized self-healing safety tire according to claim 1, characterized in that: In the self-healing rubber compound, the rubber matrix is ​​composed of natural rubber and butyl rubber in a mass ratio of 3:2; the tackifying resin is composed of terpene resin and hydrogenated C5 petroleum resin in a mass ratio of 6:1; the antioxidant is composed of antioxidant 4020 and antioxidant RD in a mass ratio of 2:1; and the additives are composed of sulfur vulcanizing agent, N-cyclohexyl-2-benzothiazole sulfenamide accelerator, and zinc stearate activator in a mass ratio of 2:3:

10.

3. The integrated vulcanized self-healing safety tire according to claim 1, characterized in that: The preparation method of the modified silica in the self-healing adhesive includes the following steps: ultrasonically dispersing silica in deionized water, and after uniform dispersion, adding γ-mercaptopropyltrimethoxysilane, wherein the mass ratio of silica, deionized water and γ-mercaptopropyltrimethoxysilane is 100:(1200-2000):(1-5), stirring and mixing, heating, adjusting the pH to 9-12 with ammonia water, reacting at 70-80℃ for 2-4 hours, after the reaction is completed, filtering, washing with anhydrous ethanol and deionized water, and drying at 60℃ for 12 hours to obtain modified silica.

4. The integrated vulcanized self-healing safety tire according to claim 1, characterized in that: The preparation method of the modified polyurethane in the self-healing adhesive includes the following steps: S1. Halloysite nanotubes were degassed under vacuum at 120℃ for 6 hours. After treatment, they were cooled to obtain pretreated halloysite nanotubes. The pretreated halloysite nanotubes were ultrasonically dispersed in toluene. After uniform dispersion, γ-glycidyl etheroxypropyltriethoxysilane was added. The mixture was heated and stirred under a nitrogen atmosphere to allow the reaction to occur. After the reaction was completed, the mixture was filtered, washed, and dried at 60℃ for 12 hours to obtain epoxidized halloysite nanotubes. S2. Add epoxidized halloysite nanotubes to N,N-dimethylformamide, disperse evenly by ultrasonication, add 4,4'-diaminodiphenyl sulfone, stir and mix, heat to allow the reaction to occur, and after the reaction is complete, rotary evaporate to obtain aminated halloysite nanotubes. S3. Aminated halloysite nanotubes and isophorone diisocyanate were reacted at 80-90℃ for 1 h, then cooled to 75℃, polypropylene glycol 2000 was added, and the reaction was carried out for 2 h. 2,2-bis(hydroxymethyl)propionic acid was added, stirred and mixed, and reacted at 80-90℃ for 2 h. 1,4-Butanediol and trimethylolpropane were added, and the reaction was carried out for 2 h. After cooling, triethylamine was added, and the reaction was carried out at 30-40℃ for 30-40 min. Deionized water was added dropwise, and high-speed shear emulsification was performed. After standing, the mixture was vacuum dried at 50℃ for 24 h to obtain modified polyurethane.

5. The integrated vulcanized self-healing safety tire according to claim 4, characterized in that: The mass ratio of N,N-dimethylformamide, epoxidized halloysite nanotubes, and 4,4'-diaminodiphenyl sulfone in S2 is (1000-1200):100:(90-112), the reaction temperature is 90-105℃, and the reaction time is 5-8h.

6. The integrated vulcanized self-healing safety tire according to claim 4, characterized in that: The mass ratio of amino-modified halloysite nanotubes, isophorone diisocyanate, polypropylene glycol 2000, 2,2-bis(hydroxymethyl)propionic acid, 1,4-butanediol, trimethylolpropane, and triethylamine in S3 is 100:(65-82):(280-350):(12-18):(8-12):(2.5-3.5):(10-16).

7. A self-sealing, vulcanized safety tire according to any one of claims 1-6, characterized in that: The manufacturing process of the integrated vulcanized self-healing safety tire includes the following steps: Step 1: Mix the self-healing compound evenly on an internal mixer and a two-roll mill to obtain the self-healing layer; Step 2: Clean the tire forming drum thoroughly, removing surface dust and oil. On the tire forming drum, attach the release film with the release surface facing inward. On the outside of the release film, attach the self-healing layer, airtight layer, transition layer, cord fabric, steel wire layer, nylon belt layer, and tread rubber in sequence from the inside out. First, use a pressure roller to compact it, press it according to the outline of the tire crown, trim any excess rubber material, and make a green tire. Let the green tire stand for 1-2 hours. Step 3: Place the green tire in a dual-mold tire vulcanizing machine for vulcanization. After vulcanization, demold, trim, and cool to obtain an integrated vulcanized self-healing safety tire.

8. The integrated vulcanized self-healing safety tire according to claim 7, characterized in that: The preparation method of the self-healing layer in step one includes the following steps: adding rubber matrix, antioxidant, zinc stearate, and modified silica into a mixer, mixing at 70-90℃ for 2-4 minutes, then adding tackifying resin and modified polyurethane, and continuing to mix at 100-120℃ for 2-3 minutes. After discharging the masterbatch, wrapping it with rollers on a two-roll mill at a roller temperature of 50-60℃, then adding accelerator N-cyclohexyl-2-benzothiazole sulfenamide and vulcanizing agent sulfur in sequence, and performing two-roll milling at a temperature of 60-70℃ and a speed of 25-35 r / min for 5-8 minutes. During the two-roll milling process, the mixture is repeatedly turned over and dispersed evenly. After that, the mixture is sheeted to obtain the self-healing layer.

9. The integrated vulcanized self-healing safety tire according to claim 7, characterized in that: In step two, the bonding temperature is 50-60℃, the pressure roller pressure is 0.5-0.8MPa, the pressing pressure is 1.0-1.2MPa, and the pressing time is 5-8min.

10. The integrated vulcanized self-healing safety tire according to claim 7, characterized in that: In step three, the vulcanization process is carried out in a nitrogen atmosphere. The vulcanization pressure is 1.8-2.2 MPa, the vulcanization temperature is 155-165℃, and the vulcanization time is 20-30 min.

Images