Self-repairing phase change energy storage temperature control tire

Abstract

The application discloses a self-repairing phase change energy storage temperature control tire and belongs to the tire manufacturing technical field. The self-repairing phase change energy storage temperature control tire comprises a phase change energy storage layer rubber sheet arranged between a base rubber of a tire tread and a crown layer, and the phase change energy storage layer rubber sheet comprises the following raw materials in parts by weight: 100 parts of high-elastic rubber matrix, 30-40 parts of filler, 20-30 parts of phase change microcapsules, 3-8 parts of activator, 2-2.5 parts of anti-aging agent, 1-2 parts of vulcanizing agent and 1-2 parts of accelerator. In the application, the phase change energy storage layer rubber sheet utilizes the latent heat absorption and release of the phase change microcapsules to realize accurate temperature control of the tire tread on one hand, and utilizes the micro-crack expansion of the tire tread to cause the phase change microcapsules to break and release the repairing agent, thereby realizing dynamic self-repairing. The two work together, thereby effectively improving the temperature control accuracy, self-repairing efficiency, durability and wide-temperature-range adaptability of the tire.

Description

Technical Field

[0001] This invention relates to the field of tire manufacturing technology, and specifically to a self-healing phase change energy storage temperature control tire. Background Technology

[0002] When tires are driven at high speeds or under high temperatures, the tire tread generates a large amount of heat due to continuous periodic deformation, and the temperature can rise above 100°C. Temperatures exceeding 95°C are considered dangerous and can lead to tire delamination or even a blowout. This temperature rise causes degradation of rubber material properties, increased rolling resistance, and accelerated wear. Therefore, effectively controlling tire operating temperature and extending tire lifespan has become a long-standing technical challenge for the tire industry.

[0003] Currently, tire thermal management technologies mainly include material modification (such as high thermal conductivity rubber), structural heat dissipation (such as setting up heat-conducting components), and phase change energy storage. Passive heat dissipation technology promotes heat dissipation by improving the thermal conductivity of the rubber matrix or adding heat-conducting / heat-dissipating structures. However, due to the inherent defect of the low thermal conductivity of rubber materials (0.15-0.26 W / (m·K) for common rubbers), the heat dissipation efficiency is limited, and it cannot dynamically respond according to the real-time temperature of the tire. Phase change energy storage technology uses the latent heat absorption of phase change materials to achieve cooling by adding phase change microcapsules to the tread compound or setting up phase change filling cavities inside the tire. However, in existing technologies, phase change materials are mostly introduced in a simple mixing manner, lacking a precise spatial layout design for the temperature distribution characteristics of different areas in the multi-layer structure of the tire, making it difficult to achieve precise temperature control. In terms of self-healing, existing research has dispersed microcapsules (particle size 5-50 μm) coated with repair agents in the rubber matrix. When cracks extend to the microcapsules, the capsule walls rupture and release repair components, achieving automatic crack repair. However, in existing self-healing technologies, the self-healing function and temperature control function are mostly designed as independent modules, and their synergistic integration and functional coupling have not yet been achieved. After microcracks appear in the tire tread, current technologies still mainly rely on external repairs afterward, making it difficult to achieve the synergistic effect of automatic repair and temperature control simultaneously during driving.

[0004] Based on this, the present invention provides a self-healing phase change energy storage temperature control tire with a phase change energy storage layer and its preparation method. By setting a phase change energy storage layer film containing phase change microcapsules between the base rubber of the tire tread and the crown belt layer, the invention aims to solve the technical problems of limited passive heat dissipation efficiency of existing tires, inaccurate temperature control due to the lack of precise spatial layout of phase change materials, and the independence and lack of synergistic integration between self-healing function and thermal management function, in order to improve the thermal management performance and durability safety of the tire. Summary of the Invention

[0005] Therefore, the present invention provides a self-healing phase change energy storage temperature control tire to solve the technical problems of existing tires in the prior art, such as performance degradation, low heat dissipation efficiency, and inability to self-repair microcracks under high temperature conditions.

[0006] To achieve the above objectives, the present invention provides the following technical solution: According to a first aspect of the present invention, a self-healing phase change energy storage temperature control tire is provided, the self-healing phase change energy storage temperature control tire comprising a phase change energy storage layer film; the phase change energy storage layer film comprises the following raw materials: a high-elastic rubber matrix, fillers, phase change microcapsules, activators, antioxidants, vulcanizing agents, and accelerators.

[0007] Furthermore, the high-elasticity rubber matrix is ​​composed of styrene-butadiene rubber and cis-butadiene rubber in a mass ratio of (60-70):(30-40).

[0008] Furthermore, the phase change microcapsules are composed of polyurethane and paraffin-based phase change materials in a mass ratio of (15-20):(80-85), and their preparation method is as follows: Melt paraffin-based phase change core material at 75-85℃, add 0.5wt.%-2wt.% emulsifier and 5-10 times the amount of deionized water, and emulsify at 3000-6000rpm for 2-5 minutes to form an oil-in-water emulsion; mix diisocyanate monomer and polyol monomer at a mass ratio of (1-3):(3-1), and stir at 70-90℃ and 300-500rpm for 1-2 hours to prepare a polyurethane prepolymer; slowly add the polyurethane prepolymer dropwise to the oil-in-water emulsion formed above, and stir at 70-90℃ and 300-500rpm for 2-4 hours; after the reaction is completed, allow to stand and cool to room temperature, filter, wash with water, vacuum dry, and sieve to obtain phase change microcapsules; The emulsifier includes, but is not limited to, polyvinyl alcohol (PVA); the diisocyanate monomer includes, but is not limited to, isophorone diisocyanate (IPDI); and the polyol monomer includes, but is not limited to, ethylene glycol (EG).

[0009] The particle size of the paraffin-based phase change material is 50-200 μm.

[0010] Furthermore, the phase change energy storage layer has a thickness of 2-4 mm and a phase change temperature range of 60-80℃.

[0011] Further, by weight, the phase change energy storage layer film comprises the following raw materials: 100 parts of high-elastic rubber matrix, 30-40 parts of filler, 20-30 parts of phase change microcapsules, 3-8 parts of activator, 2-2.5 parts of antioxidant, 1-2 parts of vulcanizing agent and 1-2 parts of accelerator.

[0012] Further, the filler is selected from at least one of silica, carbon black, and calcium carbonate; the activator is selected from at least one of zinc oxide, stearic acid, and zinc stearate; the antioxidant is selected from at least one of antioxidant 4020, antioxidant RD, and antioxidant 4010NA; the vulcanizing agent is selected from at least one of sulfur and insoluble sulfur; and the accelerator is selected from at least one of accelerator CZ, accelerator DM, accelerator D, and accelerator NS.

[0013] Further, the filler is silica (e.g., highly dispersed silica); the activator is zinc oxide and stearic acid; the antioxidant is antioxidant 4020 and antioxidant RD; the vulcanizing agent is sulfur; and the accelerator is accelerator CZ and accelerator DM.

[0014] Furthermore, the self-healing phase change energy storage temperature control tire also includes tread rubber, crown belt ply, belt ply, carcass ply, sidewall, inner liner, and bead; the tread rubber is composed of tread transition rubber, tread base rubber, and crown rubber from the inside out. The phase change energy storage layer is disposed between the tread base rubber and the crown layer.

[0015] According to a second aspect of the present invention, a method for preparing a self-healing phase change energy storage temperature-controlled tire is provided, comprising the following steps: S1. Prepare phase change energy storage layer film; S2. Add 75 parts of solution-polymerized styrene-butadiene rubber and 25 parts of butadiene rubber to a mixer and mix at 80-90℃ for 1-2 minutes. Add 75 parts of highly dispersed silica, 6 parts of silane coupling agent Si69, 8 parts of carbon black N234, 4 parts of zinc oxide, 1 part of stearic acid, 1.5 parts of antioxidant 4020, 0.8 parts of antioxidant RD, and 1.5 parts of microcrystalline wax. Mix until the rubber is discharged at 135-145℃ to obtain masterbatch. After rolling the masterbatch on a two-roll mill, add 1.8 parts of sulfur, 1.2 parts of accelerator CZ, and 0.4 parts of accelerator D. After passing through a thin mill 2-4 times, extrude the masterbatch into sheets to obtain tread rubber sheets. S3. On the belt drum of the tire forming machine, the belt layer ply, the crown belt ply, the phase change energy storage layer film obtained in step S1 and the tread film obtained in step S2 are sequentially bonded together, and then rolled and shaped to obtain the belt layer-tread assembly. S4. On the main drum of the tire forming machine, the inner liner, tire carcass ply, tire sidewall and tire bead are sequentially bonded together. After bulging, compaction and wrapping, the tire carcass assembly is obtained. S5. The belt layer-tread assembly obtained in step S3 is transferred to the tire body assembly obtained in step S4 through the transfer ring, the two are combined, rolled by the rear pressure roller, and the tire green tire is obtained after the drum is removed. S6. Place the green tire obtained in step S5 into a tire dual-mold vulcanizing machine and vulcanize it at 150-160°C and 2-3MPa for 15-20 minutes. After demolding, trim the edges to obtain a self-healing phase change energy storage temperature control tire.

[0016] Furthermore, the method for preparing the phase change energy storage layer film is as follows: Mix the high-elastic rubber matrix at 80-90℃ for 1-2 minutes; add filler, activator and antioxidant, heat and mix until the temperature reaches 135-145℃, discharge the glue to obtain the masterbatch; After the obtained masterbatch is wrapped around a roller, phase change microcapsules are slowly added at a temperature ≤100℃ and mixed for 3-5 minutes. After adding vulcanizing agent and accelerator, the mixture is passed through a thin sheet 2-4 times, then extruded to obtain a phase change energy storage layer film.

[0017] Furthermore, the parameters for the extrusion molding are as follows: The screw temperature is controlled at 70-90℃, and the die head temperature is controlled at 80-100℃.

[0018] According to a third aspect of the present invention, the application of the self-healing phase change energy storage temperature-controlled tire prepared by the aforementioned method in automobile production is provided.

[0019] Compared with the prior art, the present invention has the following advantages: (1) The self-healing phase change energy storage temperature-controlled tire of the present invention has a phase change energy storage layer with a thickness of 2-4 mm (phase change temperature range of 60-80℃) between the base rubber of the tread and the crown belt layer. It utilizes the latent heat absorption and release of the phase change material to dynamically regulate the tread temperature: when the temperature rises, it absorbs heat and melts to inhibit overheating; when the temperature drops, it solidifies and releases heat to slow down the sudden drop, so as to keep the tread working temperature stable. The maximum tread temperature of this self-healing phase change energy storage temperature-controlled tire (65-72℃) is 20%-28% lower than that of ordinary tires (90℃), which effectively avoids the degradation of rubber performance caused by high temperature and helps to reduce rolling resistance.

[0020] (2) The phase change energy storage layer film in the self-healing phase change energy storage temperature control tire of this invention is composed of a high-elastic rubber matrix and phase change microcapsules. When microcracks (width ≤ 0.5 mm) are generated in the tread, the cracks expand and cause the microcapsules to rupture, releasing paraffin-based phase change material (which also functions as a repair agent). The repair agent fills the cracks under capillary action and solidifies rapidly, achieving self-repair of the microcracks. At the same time, the high-elastic rubber matrix deforms repeatedly during rolling, actively migrating the repair agent to the crack tip, enhancing the repair efficiency. The tensile strength recovery rate of this self-healing phase change energy storage temperature control tire is as high as 92%-97%, which is 5.6-5.9 times higher than that of ordinary tires of the same specification (14%). The cracks are basically closed and there is no air leakage or bulging.

[0021] (3) The phase change energy storage layer absorbs and buffers the heat accumulation inside the tread at high temperatures, delaying the thermomechanical fatigue damage of the tread and shoulder areas; the self-healing function closes microcracks in time, preventing cracks from expanding into macroscopic delamination or cracking. The synergistic effect of the two significantly improves the durability and safety of the tire under high-speed and high-temperature conditions. The scrap time of this self-healing phase change energy storage temperature control tire (77-79h) is 31%-34% longer than that of ordinary tires (59h), and no tread delamination or shoulder cracking occurs; the wear index reaches 124-136, which is 24%-36% higher than that of ordinary tires of the same specification (100).

[0022] (4) The self-healing phase change energy storage temperature control tire of the present invention maintains good mechanical properties in a wide temperature range from -40℃ to +80℃. Specifically, at high temperatures, the phase change heat absorption inhibits the thermo-oxidative aging of the rubber matrix, and at low temperatures, the phase change heat release slows down the embrittlement caused by the glass transition of the rubber matrix, giving the tire performance stability under extreme climatic conditions and making it suitable for various climatic environments. After 10 cycles of high and low temperatures from -40℃ to 80℃, the tread rubber tensile strength retention rate of the self-healing phase change energy storage temperature control tire can still reach more than 89%, the Shore hardness fluctuation is ≤4HA, there are no obvious cracks or bulges, and the service stability in a wide temperature range is significantly better than that of ordinary tires of the same specification.

[0023] In summary, this invention provides a self-healing phase change energy storage temperature control tire, which integrates tire thermal management and self-healing functions, effectively improving the tire's temperature control accuracy, self-healing efficiency, durability, and wide temperature range adaptability. Detailed Implementation

[0024] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] According to a first aspect of the present invention, a self-healing phase change energy storage temperature control tire is provided, the self-healing phase change energy storage temperature control tire comprising a phase change energy storage layer film; the phase change energy storage layer film comprises the following raw materials: a high-elastic rubber matrix, fillers, phase change microcapsules, activators, antioxidants, vulcanizing agents and accelerators.

[0026] Furthermore, the high-elasticity rubber matrix is ​​composed of styrene-butadiene rubber and cis-butadiene rubber in a mass ratio of (60-70):(30-40).

[0027] Furthermore, the phase change microcapsules are composed of polyurethane and paraffin-based phase change materials in a mass ratio of (15-20):(80-85), and their preparation method is as follows: Melt paraffin-based phase change core material at 75-85℃, add 0.5wt.%-2wt.% emulsifier and 5-10 times the amount of deionized water, and emulsify at 3000-6000rpm for 2-5 minutes to form an oil-in-water emulsion; mix diisocyanate monomer and polyol monomer at a mass ratio of (1-3):(3-1), and stir at 70-90℃ and 300-500rpm for 1-2 hours to prepare a polyurethane prepolymer; slowly add the polyurethane prepolymer dropwise to the oil-in-water emulsion formed above, and stir at 70-90℃ and 300-500rpm for 2-4 hours; after the reaction is completed, allow to stand and cool to room temperature, filter, wash with water, vacuum dry, and sieve to obtain phase change microcapsules; Emulsifiers include, but are not limited to, polyvinyl alcohol (PVA); diisocyanate monomers include, but are not limited to, isophorone diisocyanate (IPDI); and polyol monomers include, but are not limited to, ethylene glycol (EG).

[0028] The particle size of paraffin-based phase change materials is 50-200 μm.

[0029] Furthermore, the phase change energy storage layer has a thickness of 2-4 mm and a phase change temperature range of 60-80℃.

[0030] Furthermore, by weight, the phase change energy storage layer film comprises the following raw materials: 100 parts of high-elastic rubber matrix, 30-40 parts of filler, 20-30 parts of phase change microcapsules, 3-8 parts of activator, 2-2.5 parts of antioxidant, 1-2 parts of vulcanizing agent and 1-2 parts of accelerator.

[0031] Furthermore, the filler is selected from at least one of silica, carbon black, and calcium carbonate; the activator is selected from at least one of zinc oxide, stearic acid, and zinc stearate; the antioxidant is selected from at least one of antioxidant 4020, antioxidant RD, and antioxidant 4010NA; the vulcanizing agent is selected from at least one of sulfur and insoluble sulfur; and the accelerator is selected from at least one of accelerator CZ, accelerator DM, accelerator D, and accelerator NS.

[0032] Furthermore, the filler is silica (e.g., highly dispersed silica); the activator is zinc oxide and stearic acid; the antioxidant is antioxidant 4020 and antioxidant RD; the vulcanizing agent is sulfur; and the accelerator is accelerator CZ and accelerator DM.

[0033] Furthermore, the self-healing phase change energy storage temperature control tire also includes tread rubber, crown belt ply, belt ply, carcass ply, sidewall, inner liner and bead; the tread rubber is composed of tread transition rubber, tread base rubber and crown rubber from the inside to the outside. The phase change energy storage layer is located between the base rubber of the tread and the crown layer.

[0034] According to a second aspect of the present invention, a method for preparing a self-healing phase change energy storage temperature-controlled tire is provided, comprising the following steps: S1. Prepare phase change energy storage layer film; S2. Add 75 parts of solution-polymerized styrene-butadiene rubber and 25 parts of butadiene rubber to a mixer and mix at 80-90℃ for 1-2 minutes. Add 75 parts of highly dispersed silica, 6 parts of silane coupling agent Si69, 8 parts of carbon black N234, 4 parts of zinc oxide, 1 part of stearic acid, 1.5 parts of antioxidant 4020, 0.8 parts of antioxidant RD, and 1.5 parts of microcrystalline wax. Mix until the rubber is discharged at 135-145℃ to obtain masterbatch. After rolling the masterbatch on a two-roll mill, add 1.8 parts of sulfur, 1.2 parts of accelerator CZ, and 0.4 parts of accelerator D. After passing through a thin mill 2-4 times, extrude the masterbatch into sheets to obtain tread rubber sheets. S3. On the belt drum of the tire forming machine, the belt layer ply, the crown belt ply, the phase change energy storage layer film obtained in step S1 and the tread film obtained in step S2 are sequentially bonded together, and then rolled and shaped to obtain the belt layer-tread assembly. S4. On the main drum of the tire forming machine, the inner liner, tire carcass ply, tire sidewall and tire bead are sequentially bonded together. After bulging, compaction and wrapping, the tire carcass assembly is obtained. S5. The belt layer-tread assembly obtained in step S3 is transferred to the tire body assembly obtained in step S4 through the transfer ring, the two are combined, rolled by the rear pressure roller, and the tire green tire is obtained after the drum is removed. S6. Place the green tire obtained in step S5 into a tire dual-mold vulcanizing machine and vulcanize it at 150-160°C and 2-3MPa for 15-20 minutes. After demolding, trim the edges to obtain a self-healing phase change energy storage temperature control tire.

[0035] Furthermore, the method for preparing the phase change energy storage layer film is as follows: Mix the high-elastic rubber matrix at 80-90℃ for 1-2 minutes; add filler, activator and antioxidant, heat and mix until the temperature reaches 135-145℃, discharge the glue to obtain the masterbatch; After the obtained masterbatch is wrapped around a roller, phase change microcapsules are slowly added at a temperature ≤100℃ and mixed for 3-5 minutes. After adding vulcanizing agent and accelerator, the mixture is passed through a thin sheet 2-4 times, then extruded to obtain a phase change energy storage layer film.

[0036] Furthermore, the parameters for extrusion molding are as follows: The screw temperature is controlled at 70-90℃, and the die head temperature is controlled at 80-100℃.

[0037] According to a third aspect of the present invention, the application of a self-healing phase change energy storage temperature-controlled tire prepared by the preparation method in automobile production is provided.

[0038] To better illustrate the technical effects of this invention, the following embodiments are provided.

[0039] Preparation Example 1 Preparation of phase change microcapsules 80 kg of paraffin-based phase change core material was melted at 80 °C, and 0.8 kg of polyvinyl alcohol (PVA) and 400 L of deionized water were added. The mixture was stirred at 5000 rpm for 3 min to form an oil-in-water emulsion. 13.5 kg of isophorone diisocyanate (IPDI) and 4.5 kg of ethylene glycol (EG) were mixed and stirred at 80 °C and 300-500 rpm for 1.5 h to prepare a polyurethane prepolymer. The polyurethane prepolymer was slowly added dropwise to the oil-in-water emulsion formed above and stirred at 80 °C and 400 rpm for 3 h. After the reaction was completed, the mixture was allowed to stand and cool to room temperature (25 °C), filtered, washed three times with deionized water, and vacuum dried at 45 °C and -0.1 MPa for 6 h. The mixture was then sieved through 200 mesh and 100 mesh standard sieves to obtain particles with a particle size of 80-150 μm, thus obtaining phase change microcapsules.

[0040] Preparation Example 2 Preparation of phase change energy storage layer film The high-elastic rubber matrix (composed of 65 kg of styrene-butadiene rubber SBR 1500 and 35 kg of butadiene rubber BR 9000) was mixed at 85°C for 2 min; 35 kg of highly dispersed silica, 4 kg of zinc oxide, 1 kg of stearic acid, 1.5 kg of antioxidant 4020 and 0.8 kg of antioxidant RD were added, and the mixture was heated and mixed until the temperature reached 140°C. The rubber was then discharged to obtain the masterbatch. After the obtained masterbatch was rolled, 25 kg of the phase change microcapsules obtained in Preparation Example 1 were slowly added at a temperature of 80°C and mixed for 4 min. Then, 1.8 kg of sulfur, 1.2 kg of accelerator CZ, and 0.4 kg of accelerator DM were added, and the mixture was passed through a thin tube three times before being sheeted. A cold-feed extruder was used, with the screw temperature controlled at 80°C and the die temperature at 90°C, to extrude and form a phase change energy storage layer film with a thickness of (3±0.2) mm.

[0041] Preparation Example 3 Preparation of phase change energy storage layer film The high-elastic rubber matrix (composed of 60 kg of styrene-butadiene rubber SBR 1500 and 40 kg of butadiene rubber BR 9000) was mixed at 85°C for 2 min; 30 kg of highly dispersed silica, 5 kg of zinc oxide, 2 kg of stearic acid, 1.5 kg of antioxidant 4020 and 1 kg of antioxidant RD were added, and the mixture was heated and mixed until the temperature reached 140°C. The rubber was then discharged to obtain the masterbatch. After the obtained masterbatch was rolled, 30 kg of the phase change microcapsules obtained in Preparation Example 1 were slowly added at a temperature of 80°C and mixed for 4 min. Then, 1 kg of sulfur, 1 kg of accelerator CZ, and 1 kg of accelerator DM were added, and the mixture was passed through a thin tube 3 times before being sheeted. A cold-feed extruder was used, with the screw temperature controlled at 80°C and the die head temperature at 90°C, to extrude and form a phase change energy storage layer film with a thickness of (3±0.2) mm.

[0042] Preparation Example 4 Preparation of phase change energy storage layer film The high-elastic rubber matrix (composed of 70 kg of styrene-butadiene rubber SBR 1500 and 30 kg of butadiene rubber BR 9000) was mixed at 85°C for 2 min; 40 kg of highly dispersed silica, 4 kg of zinc oxide, 2 kg of stearic acid, 1.5 kg of antioxidant 4020 and 1 kg of antioxidant RD were added, and the mixture was heated and mixed until the temperature reached 140°C. The rubber was then discharged to obtain the masterbatch. After the obtained masterbatch was rolled, 20 kg of the phase change microcapsules obtained in Preparation Example 1 were slowly added at a temperature of 80°C and mixed for 4 min. Then, 2 kg of sulfur, 0.5 kg of accelerator CZ, and 0.5 kg of accelerator DM were added, and the mixture was passed through a thin tube three times before being sheeted. A cold-feed extruder was used, with the screw temperature controlled at 80°C and the die head temperature at 90°C, to extrude and form a phase change energy storage layer film with a thickness of (3±0.2) mm.

[0043] Example 1 The method for preparing the self-healing phase change energy storage temperature control tire in this embodiment includes the following steps: S1. Add 75kg of solution-polymerized styrene-butadiene rubber and 25kg of butadiene rubber to a mixer and mix at 80-90℃ for 1-2 minutes. Add 75kg of highly dispersed silica, 6kg of silane coupling agent Si69, 8kg of carbon black N234, 4kg of zinc oxide, 1kg of stearic acid, 1.5kg of antioxidant 4020, 0.8kg of antioxidant RD and 1.5kg of microcrystalline wax, and mix until 140℃ to discharge the rubber, obtaining the masterbatch. After wrapping the masterbatch with rollers on an open mill, add 1.8kg of sulfur, 1.2kg of accelerator CZ and 0.4kg of accelerator D, and pass through a thin mill 3 times before sheeting. Use a cold-feed extruder, with the screw temperature controlled at 80℃ and the die head temperature at 90℃, to extrude and form a tread sheet with a thickness of (3±0.2)mm.

[0044] S2. On the belt drum of the tire forming machine, the belt layer cord, the crown layer cord, the phase change energy storage layer film prepared in Preparation Example 2, and the tread film obtained in step S1 are sequentially bonded together and rolled to obtain the belt layer-tread assembly. S3. On the main drum of the tire forming machine, the inner liner, tire carcass ply, tire sidewall and tire bead are sequentially attached. After bulging, compaction and wrapping, the tire carcass assembly is obtained. S4. The belt layer-tread assembly obtained in step S2 is transferred to the tire body assembly obtained in step S3 through the transfer ring. The two are combined, rolled by the rear pressure roller, and the tire green tire is obtained after the drum is removed. S5. Place the green tire obtained in step S4 into a tire dual-mold vulcanizing machine and vulcanize it at 155°C and 3MPa for 18 minutes. After demolding, trim the edges to obtain a self-repairing phase change energy storage temperature control tire.

[0045] Example 2 The method for preparing the self-healing phase change energy storage temperature control tire in this embodiment includes the following steps: S1. Add 75kg of solution-polymerized styrene-butadiene rubber and 25kg of butadiene rubber to a mixer and mix at 80-90℃ for 1-2 minutes. Add 75kg of highly dispersed silica, 6kg of silane coupling agent Si69, 8kg of carbon black N234, 4kg of zinc oxide, 1kg of stearic acid, 1.5kg of antioxidant 4020, 0.8kg of antioxidant RD and 1.5kg of microcrystalline wax, and mix until 140℃ to discharge the rubber, obtaining the masterbatch. After wrapping the masterbatch with rollers on an open mill, add 1.8kg of sulfur, 1.2kg of accelerator CZ and 0.4kg of accelerator D, and pass through a thin mill 3 times before sheeting. Use a cold-feed extruder, with the screw temperature controlled at 80℃ and the die head temperature at 90℃, to extrude and form a tread sheet with a thickness of (3±0.2)mm.

[0046] S2. On the belt drum of the tire forming machine, the belt layer ply, the crown belt ply, the phase change energy storage layer film prepared in Preparation Example 3 and the tread film obtained in step S1 are sequentially bonded together, and then rolled and shaped to obtain the belt layer-tread assembly. S3. On the main drum of the tire forming machine, the inner liner, tire carcass ply, tire sidewall and tire bead are sequentially attached. After bulging, compaction and wrapping, the tire carcass assembly is obtained. S4. The belt layer-tread assembly obtained in step S2 is transferred to the tire body assembly obtained in step S3 through the transfer ring. The two are combined, rolled by the rear pressure roller, and the tire green tire is obtained after the drum is removed. S5. Place the green tire obtained in step S4 into a tire dual-mold vulcanizing machine and vulcanize it at 155°C and 3MPa for 18 minutes. After demolding, trim the edges to obtain a self-repairing phase change energy storage temperature control tire.

[0047] Example 3 The method for preparing the self-healing phase change energy storage temperature control tire in this embodiment includes the following steps: S1. Add 75kg of solution-polymerized styrene-butadiene rubber and 25kg of butadiene rubber to a mixer and mix at 80-90℃ for 1-2 minutes. Add 75kg of highly dispersed silica, 6kg of silane coupling agent Si69, 8kg of carbon black N234, 4kg of zinc oxide, 1kg of stearic acid, 1.5kg of antioxidant 4020, 0.8kg of antioxidant RD and 1.5kg of microcrystalline wax, and mix until 140℃ to discharge the rubber, obtaining the masterbatch. After wrapping the masterbatch with rollers on an open mill, add 1.8kg of sulfur, 1.2kg of accelerator CZ and 0.4kg of accelerator D, and pass through a thin mill 3 times before sheeting. Use a cold-feed extruder, with the screw temperature controlled at 80℃ and the die head temperature at 90℃, to extrude and form a tread sheet with a thickness of (3±0.2)mm.

[0048] S2. On the belt drum of the tire forming machine, the belt layer cord, the crown belt cord, the phase change energy storage layer film prepared in Preparation Example 4 and the tread film obtained in step S1 are sequentially bonded together, and then rolled and shaped to obtain the belt layer-tread assembly. S3. On the main drum of the tire forming machine, the inner liner, tire carcass ply, tire sidewall and tire bead are sequentially attached. After bulging, compaction and wrapping, the tire carcass assembly is obtained. S4. The belt layer-tread assembly obtained in step S2 is transferred to the tire body assembly obtained in step S3 through the transfer ring. The two are combined, rolled by the rear pressure roller, and the tire green tire is obtained after the drum is removed. S5. Place the green tire obtained in step S4 into a tire dual-mold vulcanizing machine and vulcanize it at 155°C and 3MPa for 18 minutes. After demolding, trim the edges to obtain a self-repairing phase change energy storage temperature control tire.

[0049] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that no phase change energy storage film is added.

[0050] Test Example 1 Temperature control performance test To evaluate the temperature control performance of the self-healing phase change energy storage temperature-controlled tire of the present invention, the maximum tread temperature of the self-healing phase change energy storage temperature-controlled tires in Examples 1-3 and the ordinary tire in Comparative Example 1 was tested. The specific methods are as follows: Following GB / T 4502-2023 "Indoor Test Methods for Passenger Car Tire Performance", tire samples were mounted on standard test rims, inflated to 180 kPa, and placed on an indoor drum testing machine. The ambient temperature was set at 40℃, the vehicle speed was kept constant at 80 km / h, and the test was conducted continuously for 2 hours. Infrared thermal imagers were used to monitor the tread temperature changes in real time, and the highest tread temperature (℃) was recorded. Three parallel samples were set for each group, and the results are expressed as mean ± standard deviation.

[0051] The test results are shown in Table 1 below: Table 1. Test results of the highest tread temperature of self-healing phase change energy storage temperature-controlled tires in each test group (n=3)

[0052] It can be seen from Table 1 above: Compared with the ordinary tire in Comparative Example 1 (lacking the phase change energy storage layer film), the highest tread temperature of the self-healing phase change energy storage temperature control tires in Examples 1-3 was in the range of 65-72℃, which was 20%-28% lower than that of Comparative Example 1 (90℃). This result shows that the phase change energy storage layer film in the self-healing phase change energy storage temperature control tire of the present invention can effectively absorb and buffer the heat stored in the tread, and significantly suppress the overheating phenomenon of ordinary tires under high-speed and high-temperature conditions.

[0053] Test Example 2 Self-repair performance test To evaluate the self-healing performance of the self-healing phase change energy storage temperature control tire of the present invention, the tensile strength recovery rate of the self-healing phase change energy storage temperature control tires in Examples 1-3 and the ordinary tire in Comparative Example 1 was tested. The specific methods are as follows: (1) Sample preparation Referring to GB / T 528-2009 "Determination of Tensile Stress-Strain Properties of Vulcanized Rubber or Thermoplastic Rubber", self-healing phase change energy storage temperature control tires from each test group were prepared for testing according to the following requirements: Intact sample: self-healing phase change energy storage temperature control tire without any treatment; Cracked specimens: Self-healing phase change energy storage temperature control tires with microcracks (0.3±0.05) mm wide and (1.0±0.1) mm deep were cut into the tread using a cutting tool.

[0054] (2) Self-healing experimental test The intact specimens and cracked specimens prepared in (1) were installed on the same vehicle and driven for 10 km at a speed of (70±10) km / h at room temperature. After the driving was completed, dumbbell-shaped standard specimens were cut from the marked positions on the tire tread (intact specimens were taken from the corresponding positions, and cracked specimens were taken from the original crack positions). Small specimens were cut from the cracked areas of the dumbbell-shaped specimens, and the crack closure was observed using a metallographic microscope (magnification 50× to 200×). Subsequently, the maximum load of each specimen was tested using a tensile testing machine. F max Calculate the tensile strength using the following formula (). s ) and tensile strength recovery rate (%): ; Note: F maxThis indicates the maximum load (N) recorded by the tensile testing machine. A Indicates the original cross-sectional area of ​​the sample (mm²) 2 ).

[0055] ; Note: s 0 represents the tensile strength (MPa) of an intact specimen; s 1 represents the tensile strength (MPa) of the cracked specimen after it has been repaired by driving.

[0056] Three parallel samples were set up for each group, and the results are expressed as mean ± standard deviation.

[0057] The test results are shown in Table 2 below: Table 2. Test results of tensile strength recovery rate of self-healing phase change energy storage temperature-controlled tires in each test group (n=3)

[0058] It can be seen from Table 2 above: In Examples 1-3, the tensile strength recovery rate of the self-healing phase change energy storage temperature control tires was in the range of 92%-97%, the cracks were basically closed, and no air leakage or bulging was observed; while in Comparative Example 1 (lacking phase change energy storage layer film), the tensile strength recovery rate of ordinary tires was only (14±2)%, the cracks were not healed, the original microcracks were clearly visible, and there was slight air leakage in some areas.

[0059] The above results demonstrate that the phase change energy storage layer film in the self-healing phase change energy storage temperature-controlled tire of this invention can effectively trigger the self-healing function under dynamic driving conditions, achieving rapid repair of micro-cracks in the tread and significantly restoring the tire's mechanical strength. This is due to the synergistic effect of the local thermal effect generated by the phase change energy storage layer and the migration of molecular chains during driving, providing a reliable guarantee for the long-term safe use of the tire under complex road conditions.

[0060] Test Example 3 Durability test To evaluate the durability of the self-healing phase change energy storage temperature control tire of the present invention, the scrap time of the self-healing phase change energy storage temperature control tires in Examples 1-3 and the ordinary tire in Comparative Example 1 was tested. The specific methods are as follows: Referring to GB / T 4502-2023 "Indoor Test Methods for Passenger Car Tire Performance", ordinary tires of the same specification without a phase change energy storage layer (235 / 50 R19 99V) were used as the control group sample. The tires were mounted on a drum tester with the following parameters set: inflation pressure 180 kPa; load 659 kgf for 0-4 h; load 698 kgf for 4-10 h; load 775 kgf for 10-34 h; and continuous operation at an initial speed of (120±8) km / h. After the tires had accumulated 34 h of driving on the drum, operation was stopped and the tires were allowed to rest for 2 h under standard laboratory conditions. The tire pressure was then adjusted to 140 kPa, and the tires were driven for another 1.5 h at a speed of (120±8) km / h. Finally, the driving speed was reduced to (80±5) km / h, and the load was increased by 8.5% every 2 hours from the maximum load (775 kgf) until the tire was damaged. The tire's failure time was recorded. Samples were then taken from the tread delamination area, the shoulder crack area, and the undamaged area. The microstructure of the failure area was observed using a metallographic microscope (magnification 50× to 200×). Three parallel samples were set for each group, and the results are expressed as mean ± standard deviation.

[0061] The test results are shown in Table 3 below: Table 3. Test results of the scrap time of self-healing phase change energy storage temperature control tires in each test group (n=3)

[0062] It can be seen from Table 3 above: Compared with the ordinary tires in Comparative Example 1 (lacking the phase change energy storage layer film), the self-healing phase change energy storage temperature control tires in Examples 1-3 had a scrap time of 77-79 hours, which is 31%-34% longer than Comparative Example 1 (59 hours), and no failure phenomena such as tread delamination or shoulder cracking were observed in any of them; while Comparative Example 1 showed obvious failure phenomena such as tread delamination, shoulder cracking, and cracks extending to the ply layer during the test.

[0063] The above results demonstrate that the phase change energy storage layer film in this invention can significantly improve tire durability and effectively delay the accumulation of thermomechanical fatigue damage in the tread and shoulder areas, thereby extending tire lifespan. This is because the phase change energy storage layer absorbs and buffers localized heat under high-temperature conditions, reducing the heat accumulation effect inside the tire body, enhancing the structure's fatigue resistance, and providing strong support for the safety and reliability of the tire during long-distance, high-speed driving.

[0064] Test Example 4 Wear performance test Experimental methods Referring to GB / T 29041-2023 "Test Method for Road Wear of Automobile Tires", ordinary tires of the same specification without phase change energy storage layer (235 / 50 R19 99V) were used as the control group sample. The test tires were installed on the test vehicles, and the inflation pressure was set to 250 kPa. The tires were continuously driven on the specified test road at an initial speed of (80±5) km / h. After the tires had accumulated 10,000 km of driving on the test road, the tread depth at designated positions before and after the test was measured. Small samples were cut from the crown, shoulder, and bottom of the tread grooves, and the worn surface was observed using a metallographic microscope (magnification 50× to 200×).

[0065] Calculate the average wear rate and relative wear index using the following formulas: ; in, H 0 indicates the tire tread depth (μm) before the test. H 1 indicates the tire tread depth (μm) after the test. L This indicates the cumulative mileage (km).

[0066] ; The control group was Comparative Example 1, and the experimental groups were Examples 1-3.

[0067] The wear index is based on a standard tire (baseline index = 100), and the evaluation criteria are as follows: An index greater than 100 indicates that the wear resistance of the test group is better than that of the control group (lower wear rate). An index of 100 indicates that the index is comparable to the control group. An index of <100 indicates that the wear resistance is inferior to that of the control group.

[0068] Three parallel samples were set up for each group, and the results are expressed as mean ± standard deviation.

[0069] The test results are shown in Table 4 below: Table 4. Test results of average wear rate and relative wear index of self-healing phase change energy storage temperature-controlled tires in each test group (n=3)

[0070] It can be seen from Table 4 above: Compared with the ordinary tires in Comparative Example 1 (lacking the phase change energy storage layer film), the average wear rate of the self-healing phase change energy storage temperature control tires in Examples 1-3 was in the range of 21.2-24.8 μm / 1000km, significantly lower than that of Comparative Example 1; the relative wear index was in the range of 124-136, which was 24%-36% higher than that of Comparative Example 1 (100). At the same time, the tread wear of the self-healing phase change energy storage temperature control tires in Examples 1-3 was uniform, without localized uneven wear, and no tread delamination or shoulder cracking was observed; while Comparative Example 1 showed slight uneven shoulder wear, a faster wear rate, and obvious tread delamination, shoulder cracking, and cracks extending to the ply layer during the test.

[0071] The above results demonstrate that the phase change energy storage layer rubber in the self-healing phase change energy storage temperature-controlled tire of this invention effectively inhibits high-temperature softening and wear of the rubber by continuously buffering the accumulation of high temperatures on the tread. Simultaneously, the microcapsule rupture releases a repair agent to promptly close microcracks, preventing abnormal wear caused by accelerated crack propagation. The synergistic effect of these two factors significantly improves the tire's wear resistance, providing a strong guarantee for extending tire lifespan.

[0072] Test Example 5 High and low temperature environment adaptability test Referring to GB / T 2423.22-2012 "Environmental Testing Part 2: Test Methods Test N: Temperature Change" standard, a high and low temperature cycling test chamber was used to conduct temperature cycling tests on tire samples. The total duration of each cycle was 4 hours, and the specific procedure was as follows: At room temperature (25℃), the temperature was lowered to -40℃ at a rate of 5℃ / min and held for 2 hours; then, the temperature was raised to 80℃ at a rate of 5℃ / min and held for 2 hours; this cycle was repeated 10 times. Three tire samples were used in each group. After the cycle, the samples were left to stand at room temperature (25℃) for 2 hours. Referring to GB / T 528-2009 and GB / T 39693.4-2025 "Determination of Hardness of Vulcanized Rubber or Thermoplastic Rubber Part 4: Determination of Indentation Hardness by Shore Hardness Tester Method (Shore Hardness)," samples were cut from the crown of the tire tread, and tensile strength and Shore A hardness were tested. The appearance of cracking was observed, and the performance retention rate (%) was calculated using the following formula: ; Results are expressed as mean ± standard deviation.

[0073] The test results are shown in Table 5 below: Table 5. Test results of tensile strength retention rate (%) of self-healing phase change energy storage temperature control tires after low temperature (-40℃) and high temperature (80℃) for each test group (n=3)

[0074] It can be seen from Table 5 above: Compared to the ordinary tires in Comparative Example 1 (lacking the phase change energy storage layer film), the self-healing phase change energy storage temperature-controlled tires in Examples 1-3, after 10 cycles of high and low temperatures from -40℃ to 80℃, maintained a low-temperature tensile strength retention rate of 89%-94%, which is 24%-31% higher than that of Comparative Example 1 (72%); and a high-temperature tensile strength retention rate of 91%-96%, which is 20%-26% higher than that of Comparative Example 1 (76%). Meanwhile, the self-healing phase change energy storage temperature-controlled tires in Examples 1-3 showed no cracks or bulges on the tread, and the hardness change was ≤4HA; while Comparative Example 1 showed minor cracks on the tire shoulder, and the hardness change was ≥8HA.

[0075] The above results demonstrate that the self-healing phase change energy storage temperature-controlled tire of this invention maintains excellent mechanical properties across a wide temperature range of -40℃ to 80℃, significantly outperforming ordinary tires (Comparative Example 1). This is because, under low-temperature conditions, the phase change microcapsules in the phase change energy storage layer solidify and release heat, alleviating the low-temperature embrittlement of the rubber matrix; under high-temperature conditions, the phase change microcapsules absorb heat and melt, inhibiting the thermo-oxidative aging of the rubber matrix. The synergistic effect of these two processes endows the tire with performance stability under extreme climatic conditions such as extreme cold and high temperatures, making it suitable for use in various climatic environments.

[0076] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A self-healing phase change energy storage temperature control tire, characterized in that, The self-healing phase change energy storage temperature control tire includes a phase change energy storage layer film; the phase change energy storage layer film includes the following raw materials: high-elastic rubber matrix, filler, phase change microcapsules, activator, antioxidant, vulcanizing agent and accelerator.

2. The self-healing phase change energy storage temperature control tire as described in claim 1, characterized in that, The high-elasticity rubber matrix is ​​composed of styrene-butadiene rubber and cis-butadiene rubber in a mass ratio of (60-70):(30-40).

3. The self-healing phase change energy storage temperature control tire as described in claim 1, characterized in that, The phase change microcapsules are composed of polyurethane and paraffin-based phase change materials in a mass ratio of (15-20):(80-85).

4. The self-healing phase change energy storage temperature control tire as described in claim 1, characterized in that, The phase change energy storage layer has a thickness of 2-4 mm and a phase change temperature range of 60-80℃.

5. The self-healing phase change energy storage temperature control tire as described in claim 1, characterized in that, By weight, the phase change energy storage layer film comprises the following raw materials: 100 parts of high-elastic rubber matrix, 30-40 parts of filler, 20-30 parts of phase change microcapsules, 3-8 parts of activator, 2-2.5 parts of antioxidant, 1-2 parts of vulcanizing agent and 1-2 parts of accelerator.

6. The self-healing phase change energy storage temperature control tire as described in claim 5, characterized in that, The filler is selected from at least one of silica, carbon black, and calcium carbonate; the activator is selected from at least one of zinc oxide, stearic acid, and zinc stearate; the antioxidant is selected from at least one of antioxidant 4020, antioxidant RD, and antioxidant 4010NA; the vulcanizing agent is selected from at least one of sulfur and insoluble sulfur; and the accelerator is selected from at least one of accelerator CZ, accelerator DM, accelerator D, and accelerator NS.

7. The self-healing phase change energy storage temperature control tire as described in claim 1, characterized in that, The self-healing phase change energy storage temperature control tire also includes tread rubber, crown belt ply, belt ply, carcass ply, sidewall, inner liner and bead; the tread rubber is composed of tread transition rubber, tread base rubber and crown rubber from the inside to the outside. The phase change energy storage layer is disposed between the tread base rubber and the crown layer.

8. A method for preparing a self-healing phase change energy storage temperature-controlled tire, characterized in that, Includes the following steps: S1. Prepare phase change energy storage layer film; S2. Add 75 parts of solution-polymerized styrene-butadiene rubber and 25 parts of butadiene rubber to a mixer and mix at 80-90℃ for 1-2 minutes. Add 75 parts of highly dispersed silica, 6 parts of silane coupling agent Si69, 8 parts of carbon black N234, 4 parts of zinc oxide, 1 part of stearic acid, 1.5 parts of antioxidant 4020, 0.8 parts of antioxidant RD, and 1.5 parts of microcrystalline wax. Mix until the rubber is discharged at 135-145℃ to obtain masterbatch. After rolling the masterbatch on a two-roll mill, add 1.8 parts of sulfur, 1.2 parts of accelerator CZ, and 0.4 parts of accelerator D. After passing through a thin mill 2-4 times, extrude the masterbatch into sheets to obtain tread rubber sheets. S3. On the belt drum of the tire forming machine, the belt layer ply, the crown belt ply, the phase change energy storage layer film obtained in step S1 and the tread film obtained in step S2 are sequentially bonded together, and then rolled and shaped to obtain the belt layer-tread assembly. S4. On the main drum of the tire forming machine, the inner liner, tire carcass ply, tire sidewall and tire bead are sequentially bonded together. After bulging, compaction and wrapping, the tire carcass assembly is obtained. S5. The belt layer-tread assembly obtained in step S3 is transferred to the tire body assembly obtained in step S4 through the transfer ring, the two are combined, rolled by the rear pressure roller, and the tire green tire is obtained after the drum is removed. S6. Place the green tire obtained in step S5 into a tire dual-mold vulcanizing machine and vulcanize it at 150-160°C and 2-3MPa for 15-20 minutes. After demolding, trim the edges to obtain a self-healing phase change energy storage temperature control tire.

9. The preparation method according to claim 8, characterized in that, The method for preparing phase change energy storage layer films is as follows: Mix the high-elastic rubber matrix at 80-90℃ for 1-2 minutes; add filler, activator and antioxidant, heat and mix until the temperature reaches 135-145℃, discharge the glue to obtain the masterbatch; After the obtained masterbatch is wrapped around a roller, phase change microcapsules are slowly added at a temperature ≤100℃ and mixed for 3-5 minutes. After adding vulcanizing agent and accelerator, the mixture is passed through a thin sheet 2-4 times, then extruded to obtain a phase change energy storage layer film.

10. The application of the self-healing phase change energy storage temperature control tire prepared by the method described in claim 9 in automobile production.

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