Embedded integrally-formed self-repairing safety tire

Abstract

The invention discloses an embedded integrally-formed self-repairing safety tire, which comprises a tread layer, a sidewall layer, an airtight layer and a self-repairing layer, and the self-repairing layer comprises a shape memory polymer, a nano polyurethane elastomer, a microcapsule repairing agent, a gallium-based liquid alloy and a heat-conducting filler. The preparation method comprises the following steps: S1, mixing, melting and extruding the shape memory polymer, the nano polyurethane elastomer, the gallium-based liquid alloy and the heat-conducting filler to form a base material; s2, uniformly dispersing a microcapsule repairing agent on the surface of the base material through an electrostatic spraying process to form a self-repairing layer; s3, the self-repairing layer, the tread layer, the airtight layer and the sidewall layer are integrally formed through hot press forming and jointly vulcanized, and the embedded type integrally-formed self-repairing safety tire is formed. According to the prepared embedded type integrally-formed self-repairing safety tire, the air tightness retention rate is larger than 98% after puncturing and pulling repairing, tire burst is avoided through a wound with the length of 10 cm, the elongation at break of the self-repairing layer is larger than 530%, integral forming dynamic balance and uniformity are good, and the embedded type integrally-formed self-repairing safety tire can be used for various scenes.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of tire manufacturing technology, in particular to an embedded integrated self-repairing safety tire. BACKGROUND

[0002] With the rapid development of the transportation industry, tires as an important part of vehicles, their safety and reliability are increasingly concerned. In the use of traditional tires, once punctured by sharp objects such as nails, glass fragments, etc., it is easy to appear the phenomenon of air leakage, and even cause tire burst in serious cases, which brings great hidden dangers to driving safety.

[0003] In the existing tire technology, some tires have adopted some air leakage prevention measures, such as coating a layer of sealing glue on the inner wall of the tire. However, these methods have certain limitations. For example, the coated sealing glue is easily affected by environmental factors such as temperature and humidity, resulting in a decrease in its sealing performance. Moreover, during the tire driving process, the sealing glue may be displaced due to centrifugal force and other effects, and cannot repair the puncture hole in time and effectively.

[0004] The self-repairing safety tire realizes the automatic sealing function after being punctured by sharp objects by adding a special functional layer inside the tire. The core structure includes: (1) a multi-layer puncture repair assembly, which sprays high molecular composite glue on the outer surface and inner surface of the tire respectively to form a first puncture layer and a second puncture layer. (2) Dynamic repair mechanism: when foreign matter pierces, the sealing material quickly wraps the foreign matter and fills the pores. However, some existing self-repairing tires have complex production processes and high costs, which are not conducive to large-scale popularization and application. At the same time, for different types of tires such as electric motorcycle bias-ply tires, passenger car semi-steel tires and truck full-steel tires, there is a lack of a universal and efficient self-repairing solution. Future self-repairing safety tires will gradually solve the safety pain points of traditional tires through technological innovation, but their commercialization process is still limited by material performance, cost and standardization issues. In the future, with the breakthroughs in the research and development of high molecular materials, the demand for new energy vehicles and policy support, this technology is expected to become the mainstream direction of the tire industry. Therefore, it has important practical significance to develop a safety tire with good self-repairing performance, reasonable structure, simple production process and wide application range.

[0005] CN116041647 A discloses a preparation method and a repairing method of a non-pneumatic self-repairing tire, relates to the technical field of new tires, and discloses a preparation method of a non-pneumatic self-repairing tire, which comprises the following steps: obtaining tire parameters, preparing polyurethane prepolymer based on polyols and diisocyanate according to the tire parameters and a preset first matching ratio, and preparing the non-pneumatic self-repairing tire based on the polyurethane prepolymer, a catalyst, a chain extender and a repairing agent according to a preset second matching ratio and the first mass of the polyurethane prepolymer. The polyurethane prepolymer is prepared based on polyols and diisocyanate, the non-pneumatic self-repairing tire is prepared based on the polyurethane prepolymer, the catalyst, the chain extender and the repairing agent, the amino group or the hydroxyl group in the repairing agent can react with the isocyanate group in the polyurethane prepolymer, so that a disulfide bond is introduced into the polyurethane molecular main chain, the disulfide bond can be reversibly broken and recombined at a certain temperature, and the self-repairing effect is achieved. However, the technical problems existing at present cannot be solved. SUMMARY

[0006] The purpose of the present application is to provide an embedded integrally formed self-repairing safety tire, which comprises a tread layer, a sidewall layer, an airtight layer and a self-repairing layer. The self-repairing layer comprises a shape memory polymer, a nano polyurethane elastomer, a microcapsule repairing agent, a gallium-based liquid alloy and a heat-conducting filler. The mass percentages of Ga, In and Sn in the gallium-based liquid alloy are 68.5wt%, 21.5wt% and 10wt% respectively. The nano polyurethane elastomer provides high resilience and supports the structural stability after crack closure. The airtight layer has an elongation of more than 150% and a high temperature resistance of more than 220℃, and has no deformation stress after vulcanization.

[0007] Further, the self-repairing layer comprises the following substances in the following mass fractions: 30-50 parts of shape memory polymer, 15-25 parts of nano polyurethane elastomer, 10-15 parts of microcapsule repairing agent, 0-2 parts of gallium-based liquid alloy and 5-8 parts of heat-conducting filler.

[0008] Further, the shape memory polymer is a mixture of polycaprolactone, hydrogenated styrene-butadiene block copolymer and polyurethane resin, and the mass ratio of polycaprolactone, hydrogenated styrene-butadiene block copolymer and polyurethane resin is 1:1:1. The mixture of the three can reduce the glass transition temperature to as low as -38℃.

[0009] Further, the microcapsule repairing agent comprises a core material and a shell material. The core material is liquid styrene-butadiene rubber with a molecular weight of 2000-8000, and the shell material is polyurea with a molecular weight of 10000-50000. The microcapsule repairing agent has a dual-response repairing mechanism, i.e. mechanical rupture release and heat-triggered release of the core material to fill the cracks. The core material has both flexibility and adhesive strength, and the shell material ensures directional rupture under mechanical external force.

[0010] Further, the heat-conducting filler is a mixture of graphene and carbon nanotubes, and the mass ratio of graphene to carbon nanotubes is 1:1. The graphene / carbon nanotube composite filler is introduced to form a three-dimensional network structure through π-π conjugation, so as to realize the synergistic improvement of mechanical properties and self-repairing efficiency.

[0011] Further, the self-repairing layer is arranged between the tread layer and the air-tight layer, and the thickness is 1.5-3 mm.

[0012] Further, the gallium-based liquid alloy is coated with a polydopamine interface layer through microfluidic technology to generate capillary flow when deformed under stress, so as to realize secondary repair of micro-cracks.

[0013] The application further provides a preparation method of the embedded integrally-molded self-repairing safety tire. S1. The shape memory polymer, nano polyurethane elastomer, gallium-based liquid alloy and heat-conducting filler are mixed and melt-extruded to form a base material; S2. The microcapsule repairing agent is uniformly dispersed on the surface of the base material through an electrostatic spraying process to form a self-repairing layer; S3. The self-repairing layer, the tread layer, the air-tight layer and the sidewall layer are integrally molded through hot pressing to be vulcanized together to form the embedded integrally-molded self-repairing safety tire.

[0014] The embedded integrally-molded self-repairing safety tire prepared by the application has the following advantages: (1) improved driving safety: can effectively prevent tire leakage and blowout after being punctured, reduces the safety risk during driving, and protects the life safety of the driver and passengers; (2) wide application range: suitable for various types of tires, meets the needs of different traffic tools, and has good market prospects; (3) simple production process: the self-repairing layer is directly implanted during tire molding, without the need for additional complex processes, thereby reducing production costs; (4) excellent performance of self-repairing material: the self-repairing layer has high viscoelastic properties, appropriate hardness, elongation and cohesive strength, and can maintain good self-repairing performance under various environmental conditions; (5) good dynamic balance and uniformity of integrally-molded. DETAILED DESCRIPTION

[0015] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the application.

[0016] The nano polyurethane elastomer used in the examples and comparative examples of the application is produced by Shanghai Huiping Chemical Co., Ltd., the hydrogenated styrene-butadiene block copolymer used is type 6151 of Tai Xiang (Nantong) Industrial Co., Ltd., and the polyurethane resin used is type 9009-54-5 of Hubei Nuona Technology Co., Ltd. Example 1

[0017] An embedded integrally formed self-repairing safety tire comprises a tread layer, a sidewall layer, an airtight layer and a self-repairing layer, the self-repairing layer comprises the following substances in mass fraction: polycaprolactone 10 kg, hydrogenated styrene-butadiene block copolymer 10 kg, polyurethane resin 10 kg, nano polyurethane elastomer 15 kg, microcapsule repairing agent 10 kg, gallium-based liquid alloy 0 kg, graphene 2.5 kg, and carbon nanotube 2.5 kg.

[0018] The microcapsule repairing agent comprises a core material and a shell material, the core material is liquid styrene-butadiene rubber with a molecular weight of 2000-8000, and the shell material is polyurea with a molecular weight of 10000-50000, and the microcapsule repairing agent is prepared by the following method: liquid styrene-butadiene rubber is added into tetrahydrofuran, rapidly stirred and dispersed, then polyurea prepolymer is added, followed by catalytic reaction of dibutyltin dilaurate, and then filtration, washing and drying to obtain the microcapsule repairing agent, wherein the mass of the liquid styrene-butadiene rubber is 0.2 times the mass of the tetrahydrofuran, the mass of the polyurea prepolymer is 0.05 times the mass of the tetrahydrofuran, the mass of the dibutyltin dilaurate is 0.003 times the mass of the tetrahydrofuran, the reaction temperature is 60-80℃, and the reaction time is 5h.

[0019] The self-repairing layer is arranged between the tread layer and the airtight layer, and has a thickness of 2mm.

[0020] The preparation method of the above-mentioned embedded integrally formed self-repairing safety tire comprises the following steps: S1. mixing and melt-extruding a shape memory polymer, a nano polyurethane elastomer, a gallium-based liquid alloy and a heat-conducting filler to form a base material; S2. uniformly dispersing the microcapsule repairing agent on the surface of the base material by electrostatic spraying process to form a self-repairing layer; S3. integrally forming the self-repairing layer with the tread layer, the airtight layer and the sidewall layer by hot press forming, and co-vulcanizing to form the embedded integrally formed self-repairing safety tire. Example 2

[0021] An embedded integrally formed self-repairing safety tire, comprising a tread layer, a sidewall layer, an airtight layer and a self-repairing layer, the self-repairing layer comprising the following substances in mass fraction: polycaprolactone 10 kg, hydrogenated styrene-butadiene block copolymer 10 kg, polyurethane resin 10 kg, nano polyurethane elastomer 15 kg, microcapsule repair agent 10 kg, gallium-based liquid alloy 0.2 kg, graphene 2.5 kg, carbon nanotube 2.5 kg, the mass percentages of Ga, In and Sn in the gallium-based liquid alloy being 68.5 wt%, 21 wt% and 10 wt% respectively.

[0022] The microcapsule repair agent comprises a core material and a shell material, the core material being liquid styrene-butadiene rubber with a molecular weight of 2000-8000, and the shell material being polyurea with a molecular weight of 10000-50000, and the preparation method of the microcapsule repair agent being: adding liquid styrene-butadiene rubber into tetrahydrofuran, rapidly stirring and dispersing, then adding polyurea prepolymer, and then adding dibutyltin dilaurate for catalytic reaction, followed by filtration, washing and drying to obtain the microcapsule repair agent, wherein the mass of the liquid styrene-butadiene rubber is 0.2 times the mass of the tetrahydrofuran, the mass of the polyurea prepolymer is 0.05 times the mass of the tetrahydrofuran, the mass of the dibutyltin dilaurate is 0.003 times the mass of the tetrahydrofuran, the reaction temperature is 60-80℃, and the reaction time is 5h.

[0023] The self-repairing layer is arranged between the tread layer and the airtight layer, and has a thickness of 2mm.

[0024] The gallium-based liquid alloy is coated with a polydopamine interface layer by microfluidic technology, and the mass of the polydopamine is 0.3 times the mass of the gallium-based liquid alloy.

[0025] The preparation method of the above-mentioned embedded integrally formed self-repairing safety tire comprises the following steps: S1. Mixing and melt-extruding a shape memory polymer, a nano polyurethane elastomer, a gallium-based liquid alloy and a heat-conducting filler to form a base material; S2. Uniformly dispersing a microcapsule repair agent on the surface of the base material by electrostatic spraying process to form a self-repairing layer; S3. Integrally forming the self-repairing layer with the tread layer, the airtight layer and the sidewall layer by hot press molding, and co-vulcanizing to form an embedded integrally formed self-repairing safety tire. Example 3

[0026] An embedded integrally formed self-repairing safety tire, comprising a tread layer, a sidewall layer, an airtight layer and a self-repairing layer, the self-repairing layer comprising the following substances in mass fraction: polycaprolactone 12 kg, hydrogenated styrene-butadiene block copolymer 12 kg, polyurethane resin 12 kg, nano polyurethane elastomer 20 kg, microcapsule repair agent 12 kg, gallium-based liquid alloy 0 kg, graphene 4 kg, carbon nanotube 4 kg.

[0027] The microcapsule repair agent comprises a core material and a shell material, the core material is liquid styrene-butadiene rubber with a molecular weight of 2000-8000, and the shell material is polyurea with a molecular weight of 10000-50000, and the preparation method of the microcapsule repair agent is as follows: liquid styrene-butadiene rubber is added into tetrahydrofuran, dispersed by rapid stirring, then polyurea prepolymer is added, and then dibutyltin dilaurate is added for catalytic reaction, and then filtration, washing and drying are carried out to obtain the microcapsule repair agent, wherein the mass of the liquid styrene-butadiene rubber is 0.2 times the mass of the tetrahydrofuran, the mass of the polyurea prepolymer is 0.05 times the mass of the tetrahydrofuran, the mass of the dibutyltin dilaurate is 0.003 times the mass of the tetrahydrofuran, the reaction temperature is 60-80 DEG C, and the reaction time is 5 h.

[0028] The self-repairing layer is arranged between the tread layer and the air-tight layer, and has a thickness of 2 mm.

[0029] The preparation method of the embedded integrally-formed self-repairing safety tire comprises the following steps: S1. Mixing, melting and extruding a shape memory polymer, a nano polyurethane elastomer, a gallium-based liquid alloy and a heat-conducting filler to form a base material; S2. Uniformly dispersing the microcapsule repair agent on the surface of the base material by an electrostatic spraying process to form a self-repairing layer; S3. Integrally forming the self-repairing layer with the tread layer, the air-tight layer and the sidewall layer by hot press forming, and vulcanizing together to form the embedded integrally-formed self-repairing safety tire.

[0030] Comparative Example 1 The microcapsule repair agent in Example 1 is removed, and the other conditions are the same as in Example 1.

[0031] Comparative Example 2 The heat-conducting filler in Example 1 is removed, and the other conditions are the same as in Example 1.

[0032] The embedded integrally-formed self-repairing safety tires prepared in the examples and comparative examples are subjected to performance tests, and the results are shown in Table 1.

[0033] Table 1

[0034] The test data of Examples 1-3 show that the embedded integrally-formed self-repairing safety tire prepared in the application has a tire air tightness retention rate of greater than 98% after repair, does not burst after a 10 cm long wound, and has a self-repairing layer elongation at break of greater than 530%, and the comparison of the data of Examples 1 and 2 shows that the addition of the gallium-based liquid alloy is a more optimal technical solution. The data of Comparative Examples 1 and 2 show that the microcapsule repair agent and the heat-conducting filler can both improve the performance of the product.

[0035] While embodiments of the application have been shown and described, it is to be understood that the embodiments described are merely exemplary of the principles and application of the present application. Numerous modifications and adaptions can be effected without departing from the spirit and scope of the present application, which is not limited to the exact construction and arrangement described. It is intended, therefore, to cover all modifications and adaptions that fall within the scope of the claims and their equivalents.

Claims

1. An integrally molded self-healing safety tire, characterized by, The self-repairing layer comprises a shape memory polymer, a nano polyurethane elastomer, a microcapsule repairing agent, a gallium-based liquid alloy and a heat-conducting filler.

2. The flush integrally formed self-healing safety tire of claim 1, wherein, The self-repairing layer comprises the following mass fractions of substances: 30-50 parts of a shape memory polymer, 15-25 parts of a nano polyurethane elastomer, 10-15 parts of a microcapsule repairing agent, 0-2 parts of a gallium-based liquid alloy and 5-8 parts of a heat-conducting filler.

3. The flush integrally formed self-healing safety tire of claim 1, wherein, The shape memory polymer is a mixture of polycaprolactone, hydrogenated styrene-butadiene block copolymer and polyurethane resin, and the mass ratio of polycaprolactone, hydrogenated styrene-butadiene block copolymer and polyurethane resin is 1:1:

1.

4. The flush integrally formed self-healing safety tire of claim 1, wherein, The microcapsule repairing agent comprises a core material and a shell material, the core material is liquid styrene-butadiene rubber with a molecular weight of 2000-8000, and the shell material is polyurea with a molecular weight of 10000-50000.

5. The insert-molded, self-healing safety tire of claim 1, wherein, The heat-conducting filler is a mixture of graphene and carbon nanotubes, and the mass ratio of graphene to carbon nanotubes is 1:

1.

6. The insert-molded, self-healing safety tire of claim 1, wherein, The self-repairing layer is arranged between the tread layer and the air-tight layer, and has a thickness of 1.5-3 mm.

7. The insert-molded, self-healing safety tire of claim 1, wherein, The gallium-based liquid alloy is coated with a polydopamine interface layer through microfluidic technology.

8. A preparation method of the embedded integrally formed self-repairing safety tire according to any one of claims 1-7, comprising the following steps: S1. mixing and melt-extruding a shape memory polymer, a nano polyurethane elastomer, a gallium-based liquid alloy and a heat-conducting filler to form a base material; S2. uniformly dispersing a microcapsule repairing agent on the surface of the base material through an electrostatic spraying process to form a self-repairing layer; S3. integrally forming the self-repairing layer with a tread layer, an air-tight layer and a sidewall layer through hot press forming, and co-vulcanizing to form the embedded integrally formed self-repairing safety tire.

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