Composite polymer self-sealing rubber material, self-sealing rubber strip and self-sealing safety tire

Abstract

The invention discloses a composite polymer self-sealing rubber material, a self-sealing rubber strip and a self-sealing safety tire. The composite polymer self-sealing rubber material is composed of a component A and a component B, the component A is prepared from the following components in parts by weight: 25 to 45 parts of natural rubber, 10 to 18 parts of butyl rubber, 40 to 65 parts of butadiene styrene rubber, 5 to 10 parts of thermoplastic elastomer, 10.0 to 14.5 parts of plasticizer, 14.0 to 22.0 parts of tackifier, 2.2 to 4.6 parts of anti-aging agent, 10 to 16 parts of filler and 4.5 to 7.0 parts of active aid; the component B is prepared from the following components in parts by weight: 70 to 90 parts of silicon rubber, 13 to 35 parts of polyurethane resin, 0.3 to 1.2 parts of silane coupling agent, 10.0 to 16.0 parts of plasticizer, 14.0 to 22.0 parts of tackifier, 2.0 to 4.5 parts of anti-aging agent, 6.0 to 14.5 parts of filler, 3.5 to 5.5 parts of nano zinc oxide and 2.3 to 4.5 parts of stabilizer; the composite high-molecular self-sealing rubber material has relatively good mechanical property, self-sealing property and high-temperature aging resistance; and the self-sealing safety tire is not easy to separate after being integrally vulcanized with the mother tire, so that the safe and reliable self-sealing safety tire is prepared.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to a composite polymer self-sealing rubber material, a self-sealing rubber strip and a self-sealing safety tire. Background Art

[0002] Tires are consumable parts that are in direct contact with the ground. They are easily punctured by sharp objects such as nails during use. Most tires are not discovered in time after being punctured, and they continue to drive with air leakage. When sharp objects remain in the tire body, the high-pressure gas of the tire will leak at the puncture point. When the sharp object pierces the tire and leaves the body, the high-pressure gas of the tire will leak rapidly, causing safety hazards such as tire damage or tire blowout. Therefore, self-sealing polymer materials came into being. As a smart polymer material, technicians can achieve the purpose of self-sealing when it responds to damage through reasonable preparation and design of molecular materials.

[0003] For example, patent CN113502135A discloses a self-repairing rubber composition for tires, the rubber composition includes reverse vulcanized rubber prepolymer, silica-gel-catalytic repair polymer double-shell microspheres and other materials. Among them, the core material of the microspheres is a nucleophilic reagent that can induce a double decomposition reaction of the SS cross-linking bonds in the reverse vulcanized rubber prepolymer. When the tire is punctured instantly, it ruptures due to severe squeezing, and the catalytic repair agent coated inside the microspheres flows out, and quickly cross-links and polymerizes with the reverse vulcanized rubber prepolymer, playing a self-sealing role in stabilizing the tire pressure. However, the defects of this external aid repair agent are that, first, the number of repairs is limited, and once it is used up, the self-sealing function is lost; second, it is limited by the embedding technology and the compatibility of different matrices must be considered, which may lead to a reduction in mechanical properties. Third, this composition is applied to the inner wall of the tire airtight layer, and when the wheel rotates, it generates high temperature and is easy to disengage and shift, affecting the dynamic balance of the wheel, and secondary air leakage occurs at the same time.

[0004] Another type of self-sealing polymer material is to introduce active groups with dynamic interactions into the polymer molecular chain. As the polymer chain at the damaged site migrates, the reversible bonds of the active groups break and recombine, and multiple repairs can be achieved to achieve a self-sealing effect. Most existing polymer materials require external stimulation (such as light or heat, etc.) to achieve self-sealing, and the only drawback of materials that can self-seal at room temperature without stimulation is often insufficient mechanical strength. Patent CN111716834A discloses a tire self-repairing rubber strip and a preparation method thereof, which is divided into four layers of composite. This method has cumbersome steps and low mechanical properties. Therefore, how to prepare a rubber compound with both good mechanical properties and self-sealing properties, and better combine the prepared rubber strip with the tire matrix is ​​still a great challenge.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] The purpose of the present invention is to provide a composite polymer self-sealing rubber material, a self-sealing rubber strip and a self-sealing safety tire. The composite polymer self-sealing rubber material has good mechanical properties, self-sealing properties and high temperature aging resistance; and is not easy to separate from the mother tire after being vulcanized, thereby preparing a safe and reliable self-sealing safety tire.

[0007] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0008] The first aspect of the present invention provides a composite polymer self-sealing adhesive material, wherein the composite polymer self-sealing adhesive material is composed of component A and component B;

[0009] The A component comprises the following components by weight:

[0010] 25-45 parts of natural rubber, 10-18 parts of butyl rubber, 40-65 parts of styrene-butadiene rubber, 5-10 parts of thermoplastic elastomer, 10.0-14.5 parts of plasticizer, 14.0-22.0 parts of tackifier, 2.2-4.6 parts of antioxidant, 10-16 parts of filler, 4.5-7.0 parts of active additive;

[0011] The B component includes the following components by weight:

[0012] 70-90 parts of silicone rubber, 13-35 parts of polyurethane resin, 0.3-1.2 parts of silane coupling agent, 10.0-16.0 parts of plasticizer, 14.0-22.0 parts of tackifier, 2.0-4.5 parts of antioxidant, 6.0-14.5 parts of filler, 3.5-5.5 parts of nano zinc oxide and 2.3-4.5 parts of stabilizer.

[0013] Preferably, the thermoplastic elastomer includes one or both of thermoplastic polyurethane elastomer (TPU) and thermoplastic polyester elastomer (TPEE), which can improve the tear resistance and tensile strength of the puncture-proof material and improve the compatibility with the tackifying resin.

[0014] Preferably, the polyurethane resin is prepared with polytetramethylene ether glycol (PTMG) as a soft segment, 4,4'-dicyclohexylmethane diisocyanate (HMDI) as a hard segment, and piperazine and 1,4-butanediol (BDO) as a mixed chain extender. The preparation method of the polyurethane resin of the present invention is a conventional polyurethane preparation method, and the synthesized polyurethane contains multiple hydrogen bonds, which enhances the interaction force between polyurethane molecular chains, effectively improves the mechanical strength of the composite rubber, and gives the material good rapid recovery and adhesion functions.

[0015] Preferably, the silane coupling agent is selected from at least two of -aminopropyl triethoxysilane (KH550), γ-(2,3-epoxypropoxy)propyl trimethoxysilane (KH560), γ-methacryloxypropyl trimethoxysilane (KH570) and vinyl triethoxysilane (A151). The present invention can promote the formation of bonding at the interface between the inorganic and organic components of the B component rubber material, promote interface fusion, and enhance the self-sealing bonding strength of the material by mixing the silane coupling agents in equal proportions.

[0016] Preferably, the plasticizer is composed of a phthalate plasticizer and an aliphatic dibasic acid ester plasticizer, the phthalate plasticizer is dioctyl phthalate (DNOP) or dibutyl phthalate (DBP), and the aliphatic dibasic acid ester plasticizer is dioctyl adipate (DOA).

[0017] Preferably, the volume ratio of the phthalate plasticizer to the aliphatic dibasic acid ester plasticizer is (0.3-1):1.

[0018] The present invention has found through research that the two selected plasticizer types do not undergo chemical reaction, but will dissolve in each other to form a homogeneous mixed system, thereby improving the mixing compatibility of the polymer and its ingredients; the combined use of the two can make the rubber have good plasticity and fluidity, facilitate calendering, extrusion and other molding operations, and at the same time improve its mechanical properties and give the rubber higher elasticity.

[0019] Preferably, the tackifier is composed of formaldehyde resin and pentaerythritol stearate (PETS), the formaldehyde resin is p-tert-octylphenol formaldehyde resin (TKO), p-tert-butylphenol formaldehyde resin (TKB) or xylene formaldehyde resin; the volume ratio of the formaldehyde resin to pentaerythritol stearate is 1:(0.1-0.5).

[0020] Preferably, the active additive is a metal oxide; used as a reinforcing agent for rubber to make the rubber have good corrosion resistance, tear resistance, elasticity and elongation. In addition to the vulcanization effect, the metal oxide can also effectively improve the thermal conductivity of the rubber, thereby facilitating the heat dissipation of the tire, and can also prevent mold organisms or ultraviolet rays from corroding the rubber, ensuring driving safety; further, the metal oxide is selected from at least one of calcium oxide, magnesium oxide and aluminum oxide.

[0021] Preferably, the antioxidant is selected from at least one of antioxidant 264, antioxidant DNP, antioxidant 4020, antioxidant 4010, and antioxidant 445.

[0022] Preferably, the filler is selected from at least one of silica, montmorillonite and carbon black. Further, the filler is a mixture of silica, montmorillonite and carbon black in a mass ratio of 6:(2-4):(1-2).

[0023] Preferably, the stabilizer includes HST-RETS-1 and SH-826.

[0024] The second aspect of the present invention provides a composite polymer self-sealing strip, which comprises, from the outside to the inside, an anti-puncture elastic layer, a self-sealing layer and a protective layer; the anti-puncture elastic layer is prepared from component A described in any one of claims 1 to 7; the self-sealing layer is prepared from component B described in any one of claims 1 to 7; and the protective layer is a release paper or a PE film.

[0025] The third aspect of the present invention provides a method for preparing the composite polymer self-sealing strip, the method comprising the following steps:

[0026] (a) Preparation of self-sealing layer:

[0027] The polyurethane resin, nano zinc oxide and silane coupling agent in component B are stirred and mixed at 180-200°C for 1-2 hours, silicone rubber, plasticizer, antioxidant, tackifier, stabilizer and filler components are added, mixed and heated in a reaction kettle at 220-240°C and further kneaded for 2-4 hours, the material is coated, and both sides are pasted with protective layers;

[0028] (b) Preparation of anti-puncture elastic layer:

[0029] The rubber material, tackifier and thermoplastic elastomer in component A are stirred and mixed at 180-200°C for 1-2 hours, antioxidant, plasticizer, filler and additive are added, the temperature is raised to 220-240°C, and the mixing is continued in the internal mixer for 1-2 hours before discharging the material, and calendering is performed by an extruder;

[0030] (c) Preparation of composite polymer self-sealing strips:

[0031] The self-sealing layer is removed from one side of the protective layer, and then the self-sealing layer is laminated and pressed with the anti-puncture elastic layer to form a thin sheet, thereby obtaining the composite polymer self-sealing rubber strip.

[0032] The fourth aspect of the present invention also provides a use of the composite polymer self-sealing rubber strip in the preparation of an integral vulcanized self-sealing safety tire.

[0033] A fifth aspect of the present invention provides an integrated vulcanized self-sealing safety tire, wherein the integrated vulcanized self-sealing safety tire uses the composite polymer self-sealing rubber strip as a self-sealing layer; and a method for preparing the integrated vulcanized self-sealing safety tire comprises the following steps:

[0034] The protective layer of the composite polymer self-sealing rubber strip is removed, and the self-sealing layer is adhered to the inner side of the airtight layer inside the tire. The rubber strip is positioned on the tire blank, rotated, adhered and compacted, and vulcanized together with the tire blank after being formed by a tire forming machine.

[0035] Preferably, the vulcanization temperature is 150-190° C., and the vulcanization time is 20-45 min.

[0036] Compared with the prior art, the beneficial effects of the present invention include at least:

[0037] The present invention provides a composite polymer self-sealing rubber material that can be used to prepare an integral vulcanized self-sealing safety tire by screening rubber material components; the mechanical properties and sealing viscosity are improved by adding polyurethane resin, and components such as plasticizers and tackifying resins are optimized and the preparation steps are improved so that the components can be effectively compatible and cooperated, so that the prepared rubber strip has both good mechanical properties and self-sealing properties.

[0038] The one-piece vulcanized self-sealing safety tire provided by the present invention co-vulcanizes the rubber strip and the tire so that the self-sealing material is formed in the embryo, which not only has no effect on the performance of the mother tire, but also has excellent self-sealing performance of the tire; moreover, the self-sealing rubber material does not separate or flow during use, thereby ensuring the balance and safety of the tire.

[0039] The self-sealing rubber strip prepared by the present invention has good air tightness, strong adhesion, aging resistance and mechanical properties, and has strong deformation recovery ability. On the one hand, when the tread is punctured by a sharp object, the sealant can wrap the metal foreign matter and isolate it from the inside of the tire to prevent gas leakage; on the other hand, when the sharp object is pulled out from the punctured tire body, the deformation is instantly restored, and the sealant can quickly enter the punctured pores to achieve self-sealing of the tire, which can prevent instantaneous decompression after repeated punctures, ensure the stability of the air pressure in the tire, and ensure driving safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the specific embodiments or the description of the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0041] Figure 1 The synthetic route of the polyurethane used in the embodiments of the present invention;

[0042] Figure 2 It is the retention rate of tensile strength and elongation of different self-sealing strip samples after aging in the experimental examples of the present invention. DETAILED DESCRIPTION

[0043] The following embodiments of the technical solution of the present invention are described in detail in conjunction with the embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore only used as examples, and cannot be used to limit the protection scope of the present invention.

[0044] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in this application should be understood by those skilled in the art. The experimental methods used in the examples of the present invention are conventional methods unless otherwise specified; the materials and reagents used are reagents and materials that can be purchased from commercial channels unless otherwise specified.

[0045] The raw materials used in the following examples are as follows:

[0046] The polyurethane resin is a polyurethane synthesized by using polytetramethylene ether glycol (PTMG) as a soft segment, HMDI as a hard segment, and piperazine and BDO as a mixed chain extender; the preparation method thereof is a conventional method, such as Figure 1 As shown, the specific steps include:

[0047] Add PTMG2000 and HMDI in a molar ratio of 1:2 into the reactor, add 0.15wt% of the catalyst dibutyltin dilaurate, react at 80°C for 3h under nitrogen protection to obtain a prepolymer, cool to 40°C, add piperazine:BDO in a molar ratio of 3:1 as a mixed chain extender (the amount of the chain extender is 10% of the total weight of PTMG2000, HMDI and the catalyst) and react for 4h. During the whole process, add an appropriate amount of NMP to reduce the viscosity of the reaction system, react until the NCO group in the solution system is less than 5%, and remove the solvent to obtain. In order to reduce experimental errors, the polyurethanes used in the examples of the present invention and the comparative examples are materials synthesized from the same batch.

[0048] Example 1

[0049] This embodiment is a composite polymer self-sealing rubber strip and an integrated vulcanized self-sealing safety tire, and the rubber compound formula is shown in Table 1 below;

[0050] Table 1

[0051]

[0052] The preparation method of the composite polymer self-sealing strip comprises the following steps:

[0053] (1) Preparation of self-sealing layer: According to the B component formula, the polyurethane resin, nano zinc oxide and KH550 / KH560 in the weight ratio are stirred and mixed at 200° C. for 1.5 h, and silicone rubber, DNOP / DOA as a plasticizer, antioxidant 4010, TKO / PETS as a tackifier, SH-826 stabilizer, and silica / montmorillonite / carbon black filler components are added, and the mixture is heated in a reactor at 230° C. and continuously kneaded for 3 h. The material is coated to form a 2 mm thick sheet, and both sides are pasted with a protective layer of PE film;

[0054] (2) Preparation of puncture-resistant elastic layer: According to the formula of component A, the mixed rubber material, tackifier TKO / PETS, and thermoplastic elastomer TPU in the above weight ratio are stirred and mixed at 200° C. for 2 h, antioxidant 4010, plasticizer DNOP / DOA, filler silica / montmorillonite / carbon black, and auxiliary agent magnesium oxide are added, the temperature is raised to 230° C. and the mixture is continuously mixed in an internal mixer for 2 h before being discharged and calendered by an extruder;

[0055] (3) Preparation of composite polymer self-sealing strip: remove one side of the protective layer of the self-sealing layer, and laminate and press the anti-puncture elastic layer to form a 5 mm thick sheet to obtain the self-sealing strip.

[0056] The preparation method of the integral vulcanized self-sealing safety tire comprises the following steps:

[0057] The protective layer film of the prepared composite polymer self-sealing rubber strip is peeled off, and the self-sealing layer is pasted to the inner side of the airtight layer on the inner side of the tire. The rubber strip is positioned on the tire embryo, and a pressure of 40Kpa is used to rotate, adhere and compact it. After trimming, the release agent is evenly applied to the surface of the rubber strip on the bladder and the tire embryo, and it is shaped by low-pressure shaping. It is vulcanized at a temperature of 160°C for 35 minutes, and left to cool after vulcanization to obtain the self-sealing safety tire.

[0058] Example 2

[0059] This embodiment is a composite polymer self-sealing rubber strip and an integrated vulcanized self-sealing safety tire, and the rubber compound formula is shown in Table 2 below;

[0060] Table 2

[0061]

[0062] The preparation method of the composite polymer self-sealing strip comprises the following steps:

[0063] (1) Preparation of self-sealing layer: According to the B component formula, the polyurethane resin, nano zinc oxide and KH550 / KH570 in the weight ratio are stirred and mixed at 180° C. for 2 h, and silicone rubber, DNOP / DOA as a plasticizer, antioxidant 4010, TKO / PETS as a tackifier, HST-RETS-1 stabilizer, and silica / montmorillonite / carbon black filler components are added, mixed in a reactor and heated at 240° C. for further mixing for 3 h, and the material is coated to form a 2 mm thick sheet, and both sides are pasted with a protective layer of PE film;

[0064] (2) Preparation of the puncture-resistant elastic layer: According to the formula of component A, the mixed rubber material, tackifier TKO / PETS, and thermoplastic elastomer TPU in the above weight ratio are stirred and mixed at 180° C. for 2 h, antioxidant 4010, plasticizer DNOP / DOA, filler silica / montmorillonite / carbon black, and auxiliary agent magnesium oxide are added, the temperature is raised to 240° C. and the mixture is continuously mixed in an internal mixer for 2 h before being discharged and calendered by an extruder;

[0065] (3) Preparation of composite polymer self-sealing strip: remove one side of the protective layer of the self-sealing layer, and laminate and press the anti-puncture elastic layer to form a 5 mm thick sheet to obtain the self-sealing strip.

[0066] A method for preparing an integrated vulcanized self-sealing safety tire: peel off the protective layer film of a prepared composite polymer self-sealing rubber strip, stick the self-sealing layer to the inner side of the airtight layer on the inner side of the tire, position the rubber strip on the tire embryo, rotate and compact it with a pressure of 40Kpa, and after trimming, evenly apply an isolation agent to the surface of the rubber strip on the capsule and the tire embryo, shape it with a low-pressure shaping method, and vulcanize it at a temperature of 160°C for 35 minutes. After vulcanization, place it for cooling to obtain the self-sealing safety tire.

[0067] Example 3

[0068] This embodiment is a composite polymer self-sealing rubber strip and an integrated vulcanized self-sealing safety tire, and the rubber compound formula is shown in Table 3 below;

[0069] Table 3

[0070]

[0071]

[0072] The preparation method of the composite polymer self-sealing strip comprises the following steps:

[0073] (1) Preparation of self-sealing layer: According to the B component formula, the polyurethane resin, nano zinc oxide and KH560 / KH570 / A151 in the weight ratio are stirred and mixed at 200° C. for 1 hour, and silicone rubber, DNOP / DOA as a plasticizer, antioxidant 4010, TKB / PETS as a tackifier, HST-RETS-1 stabilizer, and silica / montmorillonite / carbon black filler components are added, mixed in a reactor, heated at 240° C. and continuously kneaded for 3 hours, and the material is coated to form a 2 mm thick sheet, and both sides are pasted with a protective layer of PE film;

[0074] (2) Preparation of puncture-resistant elastic layer: According to the formula of component A, the mixed rubber material, tackifier TKB / PETS, and thermoplastic elastomer TPEE in the above weight ratio are stirred and mixed at 200° C. for 1 hour, antioxidant 4010, plasticizer DNOP / DOA, filler silica / montmorillonite / carbon black, and auxiliary agent magnesium oxide are added, the temperature is raised to 240° C. and the mixture is continuously mixed in an internal mixer for 2 hours before being discharged and calendered by an extruder;

[0075] (3) Preparation of composite polymer self-sealing strip: remove one side of the protective layer of the self-sealing layer, and laminate and press the anti-puncture elastic layer to form a 5 mm thick sheet to obtain the self-sealing strip.

[0076] A method for preparing an integrated vulcanized self-sealing safety tire: peel off the protective layer film of a prepared composite polymer self-sealing rubber strip, stick the self-sealing layer to the inner side of the airtight layer on the inner side of the tire, position the rubber strip on the tire embryo, rotate and compact it with a pressure of 40Kpa, and after trimming, evenly apply an isolation agent to the surface of the rubber strip on the capsule and the tire embryo, shape it with a low-pressure shaping method, and vulcanize it at a temperature of 160°C for 35 minutes. After vulcanization, place it for cooling to obtain the self-sealing safety tire.

[0077] Example 4

[0078] This embodiment is a composite polymer self-sealing rubber strip and an integrated vulcanized self-sealing safety tire, and the rubber compound formula is shown in Table 4 below;

[0079] Table 4

[0080]

[0081]

[0082] The preparation method of the composite polymer self-sealing strip comprises the following steps:

[0083] (1) Preparation of self-sealing layer: According to the B component formula, the polyurethane resin, nano zinc oxide and KH550 / KH560 in the weight ratio are stirred and mixed at 200° C. for 1.5 h, and silicone rubber, DBP / DOA as a plasticizer, antioxidant 4020, TKB / PETS as a tackifier, SH-826 stabilizer, and silica / montmorillonite / carbon black filler components are added, mixed in a reactor and heated at 230° C. for 3 h, and the material is coated to form a 2 mm thick sheet, and both sides are pasted with a protective layer of PE film;

[0084] (2) Preparation of the puncture-resistant elastic layer: According to the formula of component A, the mixed rubber material, tackifier TKB / PETS, and thermoplastic elastomer TPU in the above weight ratio are stirred and mixed at 200° C. for 2 h, antioxidant 4020, plasticizer DBP / DOA, filler silica / montmorillonite / carbon black, and auxiliary agent magnesium oxide are added, the temperature is raised to 230° C. and the mixture is continuously mixed in an internal mixer for 2 h before being discharged and calendered by an extruder;

[0085] (3) Preparation of composite polymer self-sealing strip: remove one side of the protective layer of the self-sealing layer, and laminate and press the anti-puncture elastic layer to form a 5 mm thick sheet to obtain the self-sealing strip.

[0086] A method for preparing an integrated vulcanized self-sealing safety tire: peel off the protective layer film of a prepared composite polymer self-sealing rubber strip, stick the self-sealing layer to the inner side of the airtight layer on the inner side of the tire, position the rubber strip on the tire embryo, rotate and compact it with a pressure of 40Kpa, and after trimming, evenly apply an isolation agent to the surface of the rubber strip on the capsule and the tire embryo, shape it with a low-pressure shaping method, and vulcanize it at a temperature of 160°C for 35 minutes. After vulcanization, place it for cooling to obtain the self-sealing safety tire.

[0087] Example 5

[0088] This embodiment is a composite polymer self-sealing rubber strip and an integrated vulcanized self-sealing safety tire, and the rubber compound formula is shown in Table 5 below;

[0089] Table 5

[0090]

[0091] The preparation method of the composite polymer self-sealing strip comprises the following steps:

[0092] (1) Preparation of self-sealing layer: According to the B component formula, the polyurethane resin, nano zinc oxide and KH550 / KH570 in the weight ratio are stirred and mixed at 200° C. for 1.5 h, and silicone rubber, DBP / DOA as a plasticizer, antioxidant 4020, xylene formaldehyde resin / PETS as a tackifier, HST-RETS-1 stabilizer, and silica / montmorillonite / carbon black filler components are added, mixed in a reactor, heated at 230° C. and continued to be kneaded for 3 h, and the material is coated to form a 2 mm thick sheet, and both sides are pasted with a protective layer of PE film;

[0093] (2) Preparation of the puncture-resistant elastic layer: According to the formula of component A, the mixed rubber material, tackifier xylene formaldehyde resin / PETS, and thermoplastic elastomer TPEE in the above weight ratio are stirred and mixed at 200° C. for 2 h, antioxidant 4020, plasticizer DBP / DOA, filler silica / montmorillonite / carbon black, and auxiliary agent magnesium oxide are added, the temperature is raised to 230° C. and the mixture is continuously mixed in an internal mixer for 2 h before being discharged and calendered by an extruder;

[0094] (3) Preparation of composite polymer self-sealing strip: remove one side of the protective layer of the self-sealing layer, and laminate and press the anti-puncture elastic layer to form a 5 mm thick sheet to obtain the self-sealing strip.

[0095] A method for preparing an integrated vulcanized self-sealing safety tire: peel off the protective layer film of a prepared composite polymer self-sealing rubber strip, stick the self-sealing layer to the inner side of the airtight layer on the inner side of the tire, position the rubber strip on the tire embryo, rotate and compact it with a pressure of 40Kpa, and after trimming, evenly apply an isolation agent to the surface of the rubber strip on the capsule and the tire embryo, shape it with a low-pressure shaping method, and vulcanize it at a temperature of 160°C for 35 minutes. After vulcanization, place it for cooling to obtain the self-sealing safety tire.

[0096] Example 6

[0097] This embodiment is a composite polymer self-sealing rubber strip and an integrated vulcanized self-sealing safety tire, and the rubber compound formula is shown in Table 6 below;

[0098] Table 6

[0099]

[0100] The preparation method of the composite polymer self-sealing strip comprises the following steps:

[0101] (1) Preparation of self-sealing layer: According to the B component formula, the polyurethane resin, nano zinc oxide and KH550 / KH560 / KH570 in the weight ratio are stirred and mixed at 200° C. for 1.5 h, silicone rubber, DBP / DOA as a plasticizer, antioxidant 4020, TKO / PETS as a tackifier, SH-826 stabilizer, and silica / montmorillonite / carbon black filler components are added, mixed in a reactor and heated at 230° C. for 3 h, and the material is coated to form a 2 mm thick sheet, and both sides are pasted with a protective layer of PE film;

[0102] (2) Preparation of the puncture-resistant elastic layer: According to the formula of component A, the mixed rubber material, tackifier TKO / PETS, and thermoplastic elastomer TPU in the above weight ratio are stirred and mixed at 200° C. for 2 h, antioxidant 4020, plasticizer DBP / DOA, filler silica / montmorillonite / carbon black, and auxiliary agent magnesium oxide are added, the temperature is raised to 230° C. and the mixture is continuously mixed in an internal mixer for 2 h before being discharged and calendered by an extruder;

[0103] (3) Preparation of composite polymer self-sealing strip: remove one side of the protective layer of the self-sealing layer, and laminate and press the anti-puncture elastic layer to form a 5 mm thick sheet to obtain the self-sealing strip.

[0104] A method for preparing an integrated vulcanized self-sealing safety tire: peel off the protective layer film of a prepared composite polymer self-sealing rubber strip, stick the self-sealing layer to the inner side of the airtight layer on the inner side of the tire, position the rubber strip on the tire embryo, rotate and compact it with a pressure of 40Kpa, and after trimming, evenly apply an isolation agent to the surface of the rubber strip on the capsule and the tire embryo, shape it with a low-pressure shaping method, and vulcanize it at a temperature of 160°C for 35 minutes. After vulcanization, place it for cooling to obtain the self-sealing safety tire.

[0105] Comparative Example 1

[0106] This comparative example is a composite polymer self-sealing rubber strip and an integrated vulcanized self-sealing safety tire, and the rubber compound formula is shown in Table 7 below;

[0107] Table 7

[0108]

[0109] The preparation method of the composite polymer self-sealing strip comprises the following steps:

[0110] (1) Preparation of self-sealing layer: According to the B component formula, the polyurethane resin, silicone rubber, and DNOP / DOA plasticizer in the weight ratio are stirred and mixed at 200° C. for 1.5 h, and then antioxidant 4010, TKO / PETS as a tackifier, SH-826 stabilizer, silica / montmorillonite / carbon black filler, and magnesium oxide auxiliary component are added, and the mixture is heated in a reactor at 230° C. and continuously kneaded for 3 h. The material is coated to form a 2 mm thick sheet, and both sides are pasted with a protective layer of PE film;

[0111] The other experimental steps and conditions are the same as those in Example 1 and will not be described again here.

[0112] Comparative Example 2

[0113] This comparative example is a composite polymer self-sealing rubber strip and an integrated vulcanized self-sealing safety tire, and the rubber compound formula is shown in Table 8 below;

[0114] Table 8

[0115]

[0116] The preparation method of the composite polymer self-sealing rubber strip and the preparation method of the integrated vulcanized self-sealing safety tire are the same as those in Example 1 and will not be described in detail here.

[0117] Comparative Example 3

[0118] This comparative example is a composite polymer self-sealing rubber strip and an integrated vulcanized self-sealing safety tire, and the rubber compound formula is shown in Table 9 below;

[0119] Table 9

[0120]

[0121] The preparation method of the composite polymer self-sealing rubber strip and the preparation method of the integrated vulcanized self-sealing safety tire are the same as those in Example 1 and will not be described in detail here.

[0122] Comparative Example 4

[0123] This comparative example is a composite polymer self-sealing rubber strip and an integrated vulcanized self-sealing safety tire, and the rubber compound formula is shown in Table 10 below;

[0124] Table 10

[0125]

[0126]

[0127] The preparation method of the composite polymer self-sealing strip comprises the following steps:

[0128] (1) Preparation of self-sealing layer: According to the formula of component B, the silicone rubber, nano zinc oxide and KH550 / KH560 in the above weight proportion were stirred and mixed at 200° C. for 1.5 h, and then DNOP / DOA plasticizer, antioxidant 4010, TKO / PETS tackifier, SH-826 stabilizer, silica / montmorillonite / carbon black filler components were added, mixed and heated in a reactor at 230° C. and continued to be kneaded for 3 h, and the material was coated to form a 2 mm thick sheet, and both sides were pasted with a protective layer of PE film;

[0129] The other experimental operation steps and conditions are the same as those in Example 1 and will not be repeated here.

[0130] Comparative Example 5

[0131] This comparative example is a composite polymer self-sealing rubber strip and an integrated vulcanized self-sealing safety tire. The rubber material used in the composite polymer self-sealing rubber strip is the same as the rubber material formula of Example 1, and the difference lies in the preparation method of the self-sealing rubber strip. The specific steps are as follows:

[0132] (1) Preparation of self-sealing layer: According to the formula of component B, the polyurethane resin, nano zinc oxide, KH550 / KH560, silicone rubber, DNOP / DOA plasticizer, antioxidant 4010, TKO / PETS tackifier, SH-826 stabilizer, silica / montmorillonite / carbon black filler components in the above weight proportions are mixed in a reaction kettle and heated at 230° C. for 4.5 hours. The material is coated to form a 2 mm thick sheet, and both sides are pasted with a protective layer of PE film;

[0133] (2) Preparation of the puncture-resistant elastic layer: According to the formula of component A, the mixed rubber material, tackifier TKO / PETS, thermoplastic elastomer TPU, antioxidant 4010, plasticizer DNOP / DOA, filler silica / montmorillonite / carbon black, and auxiliary agent magnesium oxide in the above weight proportions are heated to 230° C. and mixed in an internal mixer for 4 hours, then discharged and calendered by an extruder;

[0134] (3) Preparation of composite polymer self-sealing strip: remove one side of the protective layer of the self-sealing layer, and laminate and press the anti-puncture elastic layer to form a 5 mm thick sheet to obtain the self-sealing strip.

[0135] The preparation method of the integral vulcanized self-sealing safety tire comprises the following steps:

[0136] The protective layer film of the prepared composite polymer self-sealing rubber strip is peeled off, and the self-sealing layer is pasted to the inner side of the airtight layer on the inner side of the tire. The rubber strip is positioned on the tire embryo, and a pressure of 40Kpa is used to rotate, adhere and compact it. After trimming, the release agent is evenly applied to the surface of the rubber strip on the bladder and the tire embryo, and it is shaped by low-pressure shaping. It is vulcanized at a temperature of 160°C for 35 minutes, and left to cool after vulcanization to obtain the self-sealing safety tire.

[0137] Experimental example

[0138] 1. Detection method

[0139] 1.1 Mechanical properties of rubber strips: tensile strength and elongation are both based on GB / T528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber". The sealing strip samples are cut into dumbbell shapes using a cutter. The testing machine is operated at a moving speed of 500 mm / min (tensile rate), the laboratory temperature is 27°C, and the relative humidity is 65%.

[0140] 1.2. Rebound rate: refer to GB1681-2009 "Determination of rebound elasticity of vulcanized rubber".

[0141] 1.3. Self-sealing performance: Refer to GB / T38510-2020, use a tire puncture tool to puncture the tire, and test whether the punctured tire is leaking. (1) The method for observing the leak is as follows: spray foam water on the wound. If there is a leak, foam will be generated. The more serious the leak, the more foam will be generated. (2) Tire pressure measurement: The tire self-sealing strip is pressed on the inner side of the tire airtight layer for integral vulcanization. Use a nail to puncture the tire, then pull it out, measure the pressure at intervals, and then repeat the puncture at the same position for 3 times and measure the pressure. The tire without the nail is used as a control.

[0142] 1.4. Aging resistance: The sealing strip samples were placed in a 70℃ incubator for 48 hours, and then the mechanical properties after aging were tested according to method 1. The retention rates of mechanical strength and elongation were calculated. The experimental results are as follows: Figure 2 shown.

[0143] Results Analysis

[0144] The test results of the mechanical properties and rebound rate of the rubber strip are shown in Table 11; the self-sealing performance results of the prepared tire are shown in Table 12.

[0145] Table 11

[0146]

[0147]

[0148] From Table 11, we can see that:

[0149] The self-sealing adhesive strip prepared by the embodiment of the present invention has strong mechanical properties and resilience, while changing the components and experimental steps in the comparative experiment weakens its related performance. In comparative example 1, component A replaces thermoplastic polyurethane elastomer TPU with styrene SIS, and component B does not add nano zinc oxide as modified polyurethane, and the tensile strength and elongation of the prepared adhesive strip sample are significantly reduced, and the resilience is also weakened. In the A / B component of comparative example 2, the tackifier adopts petroleum resin C5 or C9 mixed with pentaerythritol stearate (PETS), and the mechanical properties and resilience of the obtained adhesive strip are not as good as the effect of phenolic resin and PETS combined. Comparative Example 3 changes the type of plasticizer. The polar group of epoxy butyl oleate is epoxy, while that of DBP and DNOP is ester. The mixed use of epoxy butyl oleate and DOA may not be as effective as the combined use of phthalates and aliphatic dibasic acid esters in improving the compatibility of other polymers and ingredients. It is impossible to form a good homogeneous mixed system of A / B rubber materials, and thus the mechanical properties and elasticity of the obtained rubber strip material cannot be effectively improved. Compared with Comparative Example 4, the polyurethane resin added to the B component of Example 1 can enhance the interaction force between the polyurethane molecular chains, effectively improve the mechanical strength of the composite rubber material, and give the material good rapid recovery and adhesion functions because the synthesized polyurethane contains multiple hydrogen bonds. Comparative Example 5 changes the preparation steps of the rubber strip. The inventor found that by changing the order and timing of adding materials, step-by-step mixing can effectively promote the homogenization effect, and the components of the materials added first were screened. Compared with the one-step mixing method of Comparative Example 5, the preparation method determined in the embodiment of the present invention is more conducive to improving the performance of the composite rubber strip.

[0150] Depend on Figure 2 It can be seen that the self-sealing strip prepared by the present invention has good heat resistance and can still maintain good mechanical properties after aging. The mechanical strength and elongation retention rates can reach more than 90%, which can avoid the performance degradation caused by long-term driving of tires and excessive temperature, and improve the safety of vehicle driving.

[0151] Table 12

[0152]

[0153] As can be seen from Table 12, after the damaged tires were sprayed with foam water, no foam appeared in the tires made by the rubber strips of the embodiments of the present invention, indicating that the tires have good air tightness. And from the pressure test results in Table 12, it can be seen that the air pressure of the tires prepared by the present invention after puncture or repeated puncture is not significantly different from the air pressure of the tires without nails, and when the nails puncturing the tires are pulled out, no rubber seepage is seen, indicating that the rubber can recover quickly and achieve self-sealing. There is basically no leakage after repeated punctures, and the sealing stability is good.

[0154] Compared with the sealing effect decreased after replacing C5 or C9 petroleum resin in Comparative Example 2, it may be due to the fact that the TKO alkylphenolic resin in Example 1 contains phenolic hydroxyl groups, and the resin has a high polarity. When used in combination with pentaerythritol stearate, it may promote its migration to the rubber surface. When the two parts of rubber are in contact, their viscosity is affected by polarity and hydrogen bonding, and a hydrogen bonding network is easily formed between the phenolic hydroxyl groups, which is conducive to the rapid diffusion and chain entanglement of the polymer after contact. Through the diffusion of polymer molecules, the two surfaces are connected together, and the diffusion of the polymer continues and eventually forms a whole, thereby improving the adhesion and self-sealing effect. Compared with Example 1, due to the changes in components and methods in other comparative examples, the mechanical properties and resilience of the prepared materials are not as good as those in Example 1. The tensile wrapping property after foreign matter puncture and the recovery elasticity when the foreign matter is pulled out are insufficient, which will cause the rubber material to be unable to be strongly bonded and unable to achieve good self-sealing, resulting in air leakage in the tire.

[0155] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. A composite polymer self-sealing rubber material, characterized in that: The composite polymer self-sealing adhesive material is composed of component A and component B; The A component comprises the following components by weight: 25-45 parts of natural rubber, 10-18 parts of butyl rubber, 40-65 parts of styrene-butadiene rubber, 5-10 parts of thermoplastic elastomer, 10.0-14.5 parts of plasticizer, 14.0-22.0 parts of tackifier, 2.2-4.6 parts of antioxidant, 10-16 parts of filler, 4.5-7.0 parts of active additive; The B component includes the following components by weight: 70-90 parts of silicone rubber, 13-35 parts of polyurethane resin, 0.3-1.2 parts of silane coupling agent, 10.0-16.0 parts of plasticizer, 14.0-22.0 parts of tackifier, 2.0-4.5 parts of antioxidant, 6.0-14.5 parts of filler, 3.5-5.5 parts of nano zinc oxide and 2.3-4.5 parts of stabilizer.

2. The composite polymer self-sealing adhesive according to claim 1, characterized in that: The thermoplastic elastomer includes one or both of thermoplastic polyurethane elastomer and thermoplastic polyester elastomer.

3. The composite polymer self-sealing adhesive according to claim 1, characterized in that: The polyurethane resin is prepared by using polytetramethylene ether glycol as a soft segment, 4,4'-dicyclohexylmethane diisocyanate as a hard segment, and piperazine and 1,4-butanediol as a mixed chain extender.

4. The composite polymer self-sealing adhesive according to claim 1, characterized in that: The silane coupling agent is selected from at least two of aminopropyltriethoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane and vinyltriethoxysilane.

5. The composite polymer self-sealing adhesive according to claim 1, characterized in that: The plasticizer is composed of a phthalate plasticizer and an aliphatic dibasic acid ester plasticizer. The phthalate plasticizer is dioctyl phthalate or dibutyl phthalate, and the aliphatic dibasic acid ester plasticizer is dioctyl adipate.

6. The composite polymer self-sealing adhesive according to claim 1, characterized in that: The tackifier is composed of formaldehyde resin and pentaerythritol stearate, wherein the formaldehyde resin is p-tert-octylphenol formaldehyde resin, p-tert-butylphenol formaldehyde resin or xylene formaldehyde resin; and the volume ratio of the formaldehyde resin to the pentaerythritol stearate is 1:(0.1-0.5).

7. The composite polymer self-sealing adhesive according to claim 1, characterized in that: The active auxiliary agent is a metal oxide; the metal oxide is selected from at least one of calcium oxide, magnesium oxide and aluminum oxide.

8. A composite polymer self-sealing strip, characterized in that: The composite polymer self-sealing strip comprises, from outside to inside, an anti-puncture elastic layer, a self-sealing layer and a protective layer; the anti-puncture elastic layer is prepared from component A described in any one of claims 1 to 7; the self-sealing layer is prepared from component B described in any one of claims 1 to 7; the protective layer is a release paper or a PE film.

9. The method for preparing the composite polymer self-sealing strip according to claim 8, characterized in that: The steps include: (a) Preparation of self-sealing layer: The polyurethane resin, nano zinc oxide and silane coupling agent in component B are stirred and mixed at 180-200°C for 1-2 hours, silicone rubber, plasticizer, antioxidant, tackifier, stabilizer and filler components are added, mixed and heated in a reaction kettle at 220-240°C and further kneaded for 2-4 hours, the material is coated, and both sides are pasted with protective layers; (b) Preparation of anti-puncture elastic layer: The rubber material, tackifier and thermoplastic elastomer in component A are stirred and mixed at 180-200°C for 1-2 hours, antioxidant, plasticizer, filler and additive are added, the temperature is raised to 220-240°C, and the mixing is continued in the internal mixer for 1-2 hours before discharging the material, and calendering is performed by an extruder; (c) Preparation of composite polymer self-sealing strips: The self-sealing layer is removed from one side of the protective layer, and then the self-sealing layer is laminated and pressed with the anti-puncture elastic layer to form a thin sheet, thereby obtaining the composite polymer self-sealing rubber strip.

10. An integrated vulcanized self-sealing safety tire, characterized in that: The one-piece vulcanized self-sealing safety tire adopts the composite polymer self-sealing rubber strip described in claim 8 as a self-sealing layer; the preparation method of the one-piece vulcanized self-sealing safety tire comprises the following steps: The protective layer of the composite polymer self-sealing rubber strip is removed, and the self-sealing layer is adhered to the inner side of the airtight layer inside the tire. The rubber strip is positioned on the tire blank, rotated, adhered and compacted, and vulcanized together with the tire blank after being formed by a tire forming machine.

Images