A sealant for the inner liner of a puncture and explosion resistant tire and a method of making the same

Abstract

The application discloses a kind of inner liner seal rubber material for anti-puncture and anti-blast tire and preparation method thereof, and relates to tire safety protection material technical field.The application includes by mass percentage, brominated butyl rubber 32%-38%, polyisobutylene with number average molecular weight 90000-150000 7%-10%, polyisobutylene with number average molecular weight 1200-2400 17%-20%, hydrogenated carbon five-carbon nine copolymer petroleum resin 20%-26%, polybutene oil 4%-8%, maleic anhydride grafting styrene-ethylene-butylene-styrene block copolymer 7%-11%, composite limited filler 3%-6%.The application realizes step-by-step dispersion of limited component and flow component by composite limited filler pre-dispersion, rubber resin base plasticization, composite limited masterbatch structure mixing and low molecular weight polyisobutylene and polybutene oil late-stage addition.This method reduces filler agglomeration, avoids excessive softening in front stage, so that the rubber material has both puncture hole viscoelastic filling performance and form stability under high temperature and high speed.

Description

Technical Field

[0001] This invention belongs to the technical field of tire safety protection materials, and in particular relates to an inner lining sealant for puncture-proof and explosion-proof tires and its preparation method. Background Technology

[0002] Existing pneumatic tires typically consist of a tread, carcass, ply layers, airtight layer, and bead. When a vehicle is in motion, the tire relies on internal air pressure to maintain its load-bearing capacity and cushioning performance. To improve tire safety on complex road surfaces, various puncture and leak-proof solutions have been developed. Common methods include increasing carcass strength, adding tread or sidewall reinforcement structures, incorporating internal support layers, using run-flat structures, and installing a self-sealing material layer on the tire's inner wall. The self-sealing material layer is usually located inside the tire's airtight layer, covering the corresponding area of ​​the tire crown, and can extend to the vicinity of the tire shoulder depending on usage requirements. Self-sealing materials are mostly composed of butyl rubber, halogenated butyl rubber, EPDM rubber, styrene-based thermoplastic elastomers, polyisobutylene, or other high-molecular-weight elastic materials, combined with tackifying resins, softeners, reinforcing fillers, antioxidants, crosslinking agents, and other components. In use, the self-sealing material layer can be attached to the inner wall of the tire using processes such as hot melt spraying, calendering and lamination, pre-formed rubber sheet lamination, and wet mixing followed by molding. When sharp objects such as nails, metal fragments, or glass shards pierce the tire, the inner lining sealant, under the pressure of the tire and its own viscoelasticity, encapsulates the puncture. After the puncture is removed, the sealant rebounds towards the puncture channel and fills the pores, maintaining tire pressure and reducing the risk of punctures and leaks.

[0003] Existing tire liner self-sealing compounds struggle to simultaneously achieve puncture sealing capability and high-temperature, high-speed stability. To achieve rapid puncture filling, the compound typically requires high viscosity and a certain degree of fluidity. During prolonged high-speed driving, the tire's internal temperature rises, and the rubber layer is subjected to centrifugal force and repeated tire deformation. Highly fluid compounds are prone to softening, flowing, displacing, or localized accumulation, resulting in uneven liner thickness, affecting tire dynamic balance, and reducing the compound's sustained sealing effect on the puncture area. Therefore, current technology still requires a tire liner sealing compound that possesses localized viscoelastic flow and rebound sealing capabilities at the moment of puncture, while maintaining overall structural stability under high-temperature, high-speed conditions. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides an inner lining sealant for puncture-proof and explosion-proof tires and its preparation method. The technical problem this invention aims to solve is: how to address the issue that puncture-proof and explosion-proof tire inner lining sealant is difficult to simultaneously achieve both puncture sealing capability and high-temperature and high-speed morphological stability through a stepwise preparation method involving pre-dispersion of composite confined fillers, plasticization of rubber resin base material, structured mixing of composite confined masterbatch, and subsequent addition of low-molecular-weight polyisobutylene.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an inner lining sealant for puncture-proof and explosion-proof tires, comprising, by weight percentage:

[0006] Brominated butyl rubber 32%-38%;

[0007] 7%-10% of polyisobutylene with a number average molecular weight of 90,000-150,000;

[0008] Polyisobutylene with a number average molecular weight of 1200-2400 accounts for 17%-20% of the total content.

[0009] Hydrogenated C5-C9 copolymer petroleum resin 20%-26%;

[0010] Polybutene oil 4%-8%;

[0011] Maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer 7%-11%;

[0012] The composite confinement filler is 3%-6%; the composite confinement filler is composed of aminated aramid nanofibers and organically modified montmorillonite.

[0013] The present invention is further configured such that the softening point of the hydrogenated C5-C9 copolymer petroleum resin is 110℃-125℃; and the maleic anhydride grafting rate of the maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer is 1.0%-1.8%.

[0014] The present invention is further configured such that the mass ratio of the aminated aramid nanofibers to the organically modified montmorillonite is 1:1.8-1:3; the amine value of the aminated aramid nanofibers is 0.6mmol / g-1.8mmol / g, and the aspect ratio is 80-300; and the interlayer spacing of the organically modified montmorillonite is 1.8nm-3.2nm.

[0015] The present invention is further configured such that the brominated butyl rubber is a brominated isobutylene-isoprene copolymer, and the mass percentage of bromine in the brominated butyl rubber is 1.6%-2.2%.

[0016] A method for preparing an inner lining sealant for puncture-resistant and explosion-proof tires, comprising:

[0017] S1. By mass percentage, weigh out 32%-38% brominated butyl rubber, 7%-10% polyisobutylene with a number average molecular weight of 90,000-150,000, 17%-20% polyisobutylene with a number average molecular weight of 1200-2400, 20%-26% hydrogenated C5-C9 copolymer petroleum resin, 4%-8% polybutene oil, 7%-11% maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer, and 3%-6% composite confinement filler; wherein the composite confinement filler is composed of aminated aramid nanofibers and organically modified montmorillonite.

[0018] S2. After drying the composite confined filler, it is pre-dispersed and mixed with the maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer to obtain the composite confined masterbatch.

[0019] S3. The brominated butyl rubber, the polyisobutylene with a number average molecular weight of 90,000-150,000 and the hydrogenated C5-C9 copolymer petroleum resin are plasticized and mixed to obtain a rubber resin base material.

[0020] S4. The composite confined masterbatch is added to the rubber resin base material for structured mixing to obtain a rubber resin composite base material containing the composite confined masterbatch.

[0021] S5. The polyisobutylene with a number average molecular weight of 1200-2400 and the polybutene oil are added to the rubber resin composite base containing the composite confined masterbatch for dispersion and mixing, and then degassing and molding are performed to obtain the inner lining sealant for puncture-proof and explosion-proof tires.

[0022] The present invention is further configured such that the composite confined filler is obtained by premixing aminated aramid nanofibers and organically modified montmorillonite, and the premixing time is 3 min-8 min; the organically modified montmorillonite is alkyl quaternary ammonium salt modified montmorillonite.

[0023] The present invention is further configured such that the drying temperature of the composite confined filler is 80℃-100℃ and the time is 1h-2h; the temperature of the pre-dispersion mixing is 120℃-135℃, the time is 8min-15min, and the rotation speed is 40r / min-60r / min.

[0024] The present invention is further configured such that the plasticizing and mixing includes: first plasticizing the brominated butyl rubber for 3 min-6 min, then adding the polyisobutylene with a number average molecular weight of 90,000-150,000 and the hydrogenated C5-C9 copolymer petroleum resin and mixing for 8 min-14 min; the temperature of the plasticizing and mixing is 125℃-145℃.

[0025] The present invention is further configured such that the structured mixing is a segmented feeding mixing, wherein the composite confined masterbatch is added to the rubber resin base material in two parts, with a time interval of 2 min-5 min between the two additions; the structured mixing temperature is 120℃-140℃, the time is 8 min-15 min, and the rotation speed is 45 r / min-70 r / min.

[0026] The present invention is further configured such that the dispersion and mixing temperature is 90℃-110℃ and the time is 6min-12min; the degassing is vacuum degassing with a vacuum degree of 0.08MPa-0.095MPa and a degassing time of 5min-15min; the molding is calendering or extrusion molding, and the thickness of the inner lining sealant after molding is 2.5mm-4.5mm.

[0027] The beneficial effects of this invention are as follows: This invention achieves stepwise dispersion of confined components and flowing components through pre-dispersion of composite confined fillers, plasticization of rubber resin base material, structured mixing of composite confined masterbatch, and the subsequent addition of low molecular weight polyisobutylene and polybutene oil. This method reduces filler agglomeration, avoids excessive softening in the initial stage, and enables the rubber compound to possess both viscoelastic filling properties for puncture channels and morphological stability at high temperatures and high speeds.

[0028] This invention uses brominated butyl rubber as the airtight main body, employs two types of number-average molecular weight polyisobutylene to adjust cohesive strength and backfill performance, and utilizes maleic anhydride grafted block copolymer, amino-modified aramid nanofibers, and organically modified montmorillonite to form a composite confinement system. This system provides support and confinement, reducing rubber flow, displacement, and localized accumulation, maintaining uniform rubber layer thickness, and preserving the sealing effect after puncture. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0030] Figure 1 This is a flowchart illustrating the main process for preparing the inner lining sealant of this invention.

[0031] Figure 2 This is a schematic diagram of the composition of the sealing compound for the inner lining of the present invention.

[0032] Figure 3 This is a schematic diagram of the composite confined packing structure and pre-dispersion of the present invention.

[0033] Figure 4 This is a schematic diagram of the structured mixing and segmented feeding method of the present invention.

[0034] Figure 5 This is a schematic diagram of the structured mixing and segmented feeding method of the present invention. Detailed Implementation

[0035] The technical solutions of the present invention will be described below with reference to the accompanying drawings. The described embodiments are only some embodiments of the present invention, and not all embodiments.

[0036] Example 1

[0037] Please see Figures 1-5 This invention relates to an inner lining sealant for puncture-proof and explosion-proof tires, comprising, by weight percentage:

[0038] Brominated butyl rubber 34%. Brominated butyl rubber is a copolymer of brominated isobutylene and isoprene, and the mass percentage of bromine in the brominated butyl rubber is 1.9%.

[0039] 8% polyisobutylene with a number average molecular weight of 120,000.

[0040] 18% polyisobutylene with a number average molecular weight of 1800.

[0041] 23% hydrogenated C5-C9 copolymer petroleum resin.

[0042] 5% polybutene oil.

[0043] Maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer 8.

[0044] The composite confinement packing comprises 4% of the total filler. It consists of aminated aramid nanofibers and organically modified montmorillonite. The mass ratio of aminated aramid nanofibers to organically modified montmorillonite is 1:2.4. The aminated aramid nanofibers have an amine value of 1.2 mmol / g and an aspect ratio of 180. The interlayer spacing of the organically modified montmorillonite is 2.5 nm.

[0045] The softening point of the hydrogenated C5-C9 copolymer petroleum resin is 118℃. The maleic anhydride grafting rate of the maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer is 1.4%.

[0046] A method for preparing an inner lining sealant for puncture-resistant and explosion-proof tires, comprising:

[0047] S1. By mass percentage, weigh out 34% brominated butyl rubber, 8% polyisobutylene with a number average molecular weight of 120,000, 18% polyisobutylene with a number average molecular weight of 1,800, 23% hydrogenated C5-C9 copolymer petroleum resin, 5% polybutene oil, 8% maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer, and 4% composite confinement filler. The composite confinement filler is composed of aminated aramid nanofibers and organically modified montmorillonite. The composite confinement filler is obtained by premixing aminated aramid nanofibers and organically modified montmorillonite for 5 minutes. The organically modified montmorillonite is alkyl quaternary ammonium salt modified montmorillonite.

[0048] S2. After drying the composite confined filler, it is pre-dispersed and mixed with maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer to obtain the composite confined masterbatch. The drying temperature of the composite confined filler is 90℃, and the time is 1.5h. The pre-dispersion and mixing temperature is 128℃, the time is 12min, and the rotation speed is 50r / min.

[0049] S3. Brominated butyl rubber, polyisobutylene with a number average molecular weight of 120,000, and hydrogenated C5-C9 copolymer petroleum resin are plasticized and mixed to obtain a rubber resin base material. The plasticizing and mixing process includes: first, plasticizing the brominated butyl rubber for 4 minutes, then adding the polyisobutylene with a number average molecular weight of 120,000 and the hydrogenated C5-C9 copolymer petroleum resin and mixing for 11 minutes. The plasticizing and mixing temperature is 135℃.

[0050] S4. The composite confined masterbatch is added to the rubber resin base material for structured mixing to obtain a rubber resin composite base material containing the composite confined masterbatch. The structured mixing is a staged feeding mixing process, in which the composite confined masterbatch is added to the rubber resin base material in two stages, with a time interval of 3 minutes between the two additions. The structured mixing temperature is 130℃, the time is 12 minutes, and the rotation speed is 55 r / min.

[0051] S5. Polyisobutylene and polybutene oil with a number average molecular weight of 1800 were added to a rubber resin composite base containing a composite confined masterbatch for dispersion and mixing. After degassing and molding, an inner lining sealant for puncture-proof and explosion-proof tires was obtained. The dispersion and mixing temperature was 100℃, and the time was 9 min. Degassing was performed under vacuum at a vacuum degree of 0.09 MPa for 10 min. Molding was performed by calendering, and the thickness of the inner lining sealant after molding was 3.5 mm.

[0052] This embodiment represents a balanced approach. The composition of the rubber matrix, resin, mobile phase, and composite confined filler in the rubber compound is well-balanced, resulting in good coordination between puncture resistance, pore filling performance after puncture, and morphology retention under high temperature and high speed. This approach is suitable for everyday road conditions such as passenger car tires and electric vehicle tires, balancing puncture resistance, driving comfort, and processing stability.

[0053] Example 2

[0054] Please see Figures 1-5 Based on Example 1, an inner lining sealant for puncture-proof and explosion-proof tires comprises, by weight percentage:

[0055] Brominated butyl rubber 32%. Brominated butyl rubber is a copolymer of brominated isobutylene and isoprene, and the mass percentage of bromine in the brominated butyl rubber is 1.6%.

[0056] 7% polyisobutylene with a number average molecular weight of 90,000.

[0057] 20% polyisobutylene with a number average molecular weight of 1200.

[0058] 21% hydrogenated C5-C9 copolymer petroleum resin.

[0059] Polybutene oil 8%.

[0060] 7. Maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer

[0061] The composite confinement packing comprises 5% of the total filler. It consists of aminated aramid nanofibers and organically modified montmorillonite. The mass ratio of aminated aramid nanofibers to organically modified montmorillonite is 1:1.8. The aminated aramid nanofibers have an amine value of 0.8 mmol / g and an aspect ratio of 120. The interlayer spacing of the organically modified montmorillonite is 2.0 nm.

[0062] The softening point of the hydrogenated C5-C9 copolymer petroleum resin is 110℃. The maleic anhydride grafting rate of the maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer is 1.0%.

[0063] A method for preparing an inner lining sealant for puncture-resistant and explosion-proof tires, comprising:

[0064] S1. By mass percentage, weigh out 32% brominated butyl rubber, 7% polyisobutylene with a number average molecular weight of 90,000, 20% polyisobutylene with a number average molecular weight of 1,200, 21% hydrogenated C5-C9 copolymer petroleum resin, 8% polybutene oil, 7% maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer, and 5% composite confinement filler. The composite confinement filler is composed of aminated aramid nanofibers and organically modified montmorillonite. The composite confinement filler is obtained by premixing aminated aramid nanofibers and organically modified montmorillonite for 3 minutes. The organically modified montmorillonite is alkyl quaternary ammonium salt modified montmorillonite.

[0065] S2. After drying the composite confined filler, it is pre-dispersed and mixed with maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer to obtain the composite confined masterbatch. The drying temperature of the composite confined filler is 80℃ and the time is 1h. The pre-dispersion and mixing temperature is 120℃, the time is 8min, and the rotation speed is 40r / min.

[0066] S3. Brominated butyl rubber, polyisobutylene with a number average molecular weight of 90,000, and hydrogenated C5-C9 copolymer petroleum resin are plasticized and mixed to obtain a rubber resin base material. The plasticizing and mixing process includes: first, plasticizing the brominated butyl rubber for 3 minutes, then adding the polyisobutylene with a number average molecular weight of 90,000 and the hydrogenated C5-C9 copolymer petroleum resin and mixing for 8 minutes. The plasticizing and mixing temperature is 125℃.

[0067] S4. The composite confined masterbatch is added to the rubber resin matrix for structured mixing to obtain a rubber resin composite matrix containing the composite confined masterbatch. The structured mixing is a staged feeding mixing process, in which the composite confined masterbatch is added to the rubber resin matrix in two stages, with a 2-minute interval between the two additions. The structured mixing temperature is 120℃, the time is 8 minutes, and the rotation speed is 45 r / min.

[0068] S5. Polyisobutylene and polybutene oil with a number average molecular weight of 1200 were added to a rubber resin composite base containing a composite confined masterbatch for dispersion and mixing. After degassing and molding, an inner lining sealant for puncture-proof and explosion-proof tires was obtained. The dispersion and mixing temperature was 90℃, and the time was 6 minutes. Degassing was performed under vacuum at a vacuum degree of 0.08 MPa for 5 minutes. Molding was performed by extrusion molding, and the thickness of the inner lining sealant after molding was 2.5 mm.

[0069] This embodiment prioritizes puncture filling performance. The viscoelastic flow component in the rubber compound participates in puncture channel backfilling at a relatively higher proportion, making it easier for the compound to rebound and fill the puncture channel after the puncture is removed. This approach is suitable for scenarios with high puncture risk and relatively low driving speeds, such as urban commuting, low-speed delivery vehicles, and two-wheeled electric vehicles. This solution focuses more on timely sealing after puncture.

[0070] Example 3

[0071] Please see Figures 1-5 Based on Examples 1 and 2, an inner lining sealant for puncture-proof and explosion-proof tires comprises, by weight percentage:

[0072] Brominated butyl rubber 36%. Brominated butyl rubber is a copolymer of brominated isobutylene and isoprene, and the mass percentage of bromine in the brominated butyl rubber is 2.2%.

[0073] 9.5% polyisobutylene with a number average molecular weight of 150,000.

[0074] 17% polyisobutylene with a number average molecular weight of 2400.

[0075] 20% hydrogenated C5-C9 copolymer petroleum resin.

[0076] Polybutene oil 4%.

[0077] Maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer 8.5%.

[0078] The composite confinement packing material accounts for 5%. It consists of aminated aramid nanofibers and organically modified montmorillonite. The mass ratio of aminated aramid nanofibers to organically modified montmorillonite is 1:3. The aminated aramid nanofibers have an amine value of 1.8 mmol / g and an aspect ratio of 300. The interlayer spacing of the organically modified montmorillonite is 3.2 nm.

[0079] The softening point of the hydrogenated C5-C9 copolymer petroleum resin is 125℃. The maleic anhydride grafting rate of the maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer is 1.8%.

[0080] A method for preparing an inner lining sealant for puncture-resistant and explosion-proof tires, comprising:

[0081] S1. By mass percentage, weigh out 36% brominated butyl rubber, 9.5% polyisobutylene with a number average molecular weight of 150,000, 17% polyisobutylene with a number average molecular weight of 2,400, 20% hydrogenated C5-C9 copolymer petroleum resin, 4% polybutene oil, 8.5% maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer, and 5% composite confinement filler. The composite confinement filler is composed of aminated aramid nanofibers and organically modified montmorillonite. The composite confinement filler is obtained by premixing aminated aramid nanofibers and organically modified montmorillonite for 8 minutes. The organically modified montmorillonite is alkyl quaternary ammonium salt modified montmorillonite.

[0082] S2. After drying the composite confined filler, it is pre-dispersed and mixed with maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer to obtain the composite confined masterbatch. The drying temperature of the composite confined filler is 100℃ and the time is 2h. The pre-dispersion and mixing temperature is 135℃, the time is 15min, and the rotation speed is 60r / min.

[0083] S3. Brominated butyl rubber, polyisobutylene with a number average molecular weight of 150,000, and hydrogenated C5-C9 copolymer petroleum resin are plasticized and mixed to obtain a rubber resin base material. The plasticizing and mixing process includes: first, plasticizing the brominated butyl rubber for 6 minutes, then adding the polyisobutylene with a number average molecular weight of 150,000 and the hydrogenated C5-C9 copolymer petroleum resin and mixing for 14 minutes. The plasticizing and mixing temperature is 145℃.

[0084] S4. The composite confined masterbatch is added to the rubber resin base material for structured mixing to obtain a rubber resin composite base material containing the composite confined masterbatch. The structured mixing is a staged feeding mixing process, in which the composite confined masterbatch is added to the rubber resin base material in two stages, with a time interval of 5 minutes between the two additions. The structured mixing temperature is 140℃, the time is 15 minutes, and the rotation speed is 70 r / min.

[0085] S5. Polyisobutylene and polybutene oil with a number average molecular weight of 2400 were added to a rubber resin composite base containing a composite confined masterbatch for dispersion and mixing. After degassing and molding, an inner lining sealant for puncture-proof and explosion-proof tires was obtained. The dispersion and mixing temperature was 110℃, and the time was 12 min. Degassing was performed under vacuum at a vacuum degree of 0.095 MPa for 15 min. Molding was performed by calendering, and the thickness of the inner lining sealant after molding was 4.5 mm.

[0086] This embodiment prioritizes high-temperature and high-speed stability. The rubber skeleton, grafted block copolymer, and composite confined filler in the rubber compound provide stronger confinement, making the rubber layer less prone to flow, displacement, and accumulation under conditions of tire heating, centrifugal force, and repeated tire deformation. It is suitable for tire scenarios with long-term high-speed driving, high tire temperature, or large load variations, and focuses more on the morphological stability of the rubber layer during long-term service.

[0087] Example 4

[0088] This embodiment compares the effects of different formulation values ​​on the performance of the inner lining sealant, setting up experiments A, B, and C. All three experiments were used to prepare the inner lining sealant for puncture-resistant and explosion-proof tires. Except for the different formulation values ​​and corresponding preparation parameters, all three experiments used the same batch of 205 / 55R16 tires, the same tread inner wall treatment method, and the same coating area.

[0089] The rubber compound was applied to the inner wall area of ​​the tire corresponding to the center of the tread. The thickness of the rubber layer used for performance testing was controlled at 3.5mm ± 0.1mm, and the tire inflation pressure was 250kPa. Three tires were used in each experiment, and the test results were taken as the arithmetic mean.

[0090] 1. Weighing raw materials

[0091] Experiment A used the median value. The following components were weighed: 34.0% brominated butyl rubber, 8.0% polyisobutylene with a number average molecular weight of 120,000, 18.0% polyisobutylene with a number average molecular weight of 1,800, 23.0% hydrogenated C5-C9 copolymer petroleum resin, 5.0% polybutene oil, 8.0% maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer, and 4.0% composite confinement filler. In the formulation of Experiment A, the proportions of the rubber matrix, resin phase, and mobile phase were relatively balanced.

[0092] Experiment B increased the amount of polyisobutylene and polybutene oil with a number average molecular weight of 1200 during weighing. Specifically, the composition was: brominated butyl rubber 32.0%, polyisobutylene with a number average molecular weight of 90,000 7.0%, polyisobutylene with a number average molecular weight of 1200 20.0%, hydrogenated C5-C9 copolymer petroleum resin 21.0%, polybutene oil 8.0%, maleic anhydride grafted block copolymer 7.0%, and composite confined filler 5.0%. Experiment B was more suited to flow filling after pore formation.

[0093] Experiment C increased the proportion of brominated butyl rubber and polyisobutylene with a number average molecular weight of 150,000. The following components were weighed: 36.0% brominated butyl rubber, 9.5% polyisobutylene with a number average molecular weight of 150,000, 17.0% polyisobutylene with a number average molecular weight of 2,400, 20.0% hydrogenated C5-C9 copolymer petroleum resin, 4.0% polybutene oil, 8.5% maleic anhydride grafted block copolymer, and 5.0% composite confining filler. Experiment C formulation had a higher proportion of matrix bonding and confining support.

[0094] 2. Composite confined packing treatment

[0095] In Experiment A, aminated aramid nanofibers and organically modified montmorillonite were prepared at a ratio of 1:2.4. The aminated aramid nanofibers had an amine value of 1.2 mmol / g and an aspect ratio of 180. The interlayer spacing of the organically modified montmorillonite was 2.5 nm. After drying the filler at 90℃ for 1.5 h, the mass percentage of the residue on the sieve was 0.6%.

[0096] Experiment B used a lower pretreatment strength for the filler. The mass ratio of aminated aramid nanofibers to organically modified montmorillonite was 1:1.8. The amine value of the aminated aramid nanofibers was 0.8 mmol / g, the aspect ratio was 120, and the interlayer spacing of the organically modified montmorillonite was 2.0 nm. The filler was dried at 80℃ for 1 h. After drying, the mass percentage of residue on the sieve was 1.1%, which was higher than that in Experiments A and C.

[0097] Experiment C had the most stringent packing material treatment conditions. The mass ratio of aminated aramid nanofibers to organically modified montmorillonite was 1:3.0. The amine value of the aminated aramid nanofibers was 1.8 mmol / g, the aspect ratio was 300, and the interlayer spacing of the organically modified montmorillonite was 3.2 nm. After drying the packing material at 100℃ for 2 h, the mass percentage of residue on the sieve decreased to 0.4%, which was lower than that in Experiments A and B.

[0098] 3. Preparation of composite confined masterbatch

[0099] The dried composite confined filler was pre-dispersed and mixed with maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer.

[0100] Experiment A involved treating the material at 128℃ and 50r / min for 12 minutes. After tableting, the resulting masterbatch showed 3 agglomerated particles per square centimeter. The masterbatch surface was relatively smooth, and the filler was evenly distributed.

[0101] Experiment B had lower pre-dispersion temperature and shear strength. The treatment conditions were 120℃, 40 r / min, and 8 min. During tablet observation, 7 agglomerated particles were visible per square centimeter. Under the same tablet observation conditions, the number of visible agglomerated particles in Experiment B was higher than in Experiments A and C.

[0102] Experiment C involved treatment at 135℃ and 60 r / min for 15 min. After tableting, two agglomerated particles were visible per square centimeter. The number of visible agglomerated particles in Experiment C was lower than that in Experiments A and B.

[0103] 4. Preparation of rubber resin base material

[0104] In Experiment A, brominated butyl rubber was first plasticized for 4 minutes, then polyisobutylene with a number-average molecular weight of 120,000 and hydrogenated C5-C9 copolymer petroleum resin were added, and the mixture was continued to be mixed at 135°C for 11 minutes. The resulting rubber resin base had a rotational viscosity of 5200 mPa·s at 100°C.

[0105] Experiment B shortened the plasticizing and mixing time. After plasticizing brominated butyl rubber for 3 minutes, polyisobutylene with a number average molecular weight of 90,000 and resin were added, and mixed at 125°C for 8 minutes. The resulting base material had a rotational viscosity of 3900 mPa·s at 100°C, and its fluidity was greater than that of Experiment A.

[0106] Experiment C employed more stringent plasticizing conditions. After plasticizing brominated butyl rubber for 6 minutes, polyisobutylene with a number-average molecular weight of 150,000 and resin were added, and the mixture was stirred at 145°C for 14 minutes. The resulting matrix had a rotational viscosity of 7100 mPa·s at 100°C, exhibiting the highest matrix viscosity.

[0107] 5. Structured mixing

[0108] Each group of composite confined masterbatch was added to the corresponding rubber resin base.

[0109] Experiment A employed a two-stage feeding method, with a 3-minute interval between the two feedings, followed by structured mixing at 130℃ and 55 r / min for 12 minutes. The resulting composite matrix, after being vertically placed at 120℃ for 2 hours, exhibited a flow distance of 3.4 mm.

[0110] Experiment B also involved adding the composite confined masterbatch in two separate additions, but with the interval shortened to 2 minutes. The structured mixing conditions were 120℃, 45 r / min, and 8 minutes. The flow distance of the composite base at 120℃ was 6.1 mm, indicating that the high-temperature retention capacity of the rubber compound decreased when the proportion of the mobile phase was high.

[0111] Experiment C extended the interval between two feedings to 5 minutes and mixed the materials at 140℃ and 70 r / min for 15 minutes. The flow distance of this composite matrix at 120℃ was 1.9 mm. Compared with Experiments A and B, Experiment C had a smaller flow distance at 120℃.

[0112] 6. Dispersion, mixing, degassing, and molding

[0113] Experiment A involved adding polyisobutylene and polybutene oil with a number-average molecular weight of 1800 to a composite base and dispersing and mixing them at 100°C for 9 minutes. Subsequently, the mixture was degassed under a vacuum of 0.09 MPa for 10 minutes, followed by calendering. The adhesive layer thickness was controlled at 3.5 mm ± 0.1 mm. After molding, two air bubbles were visible per 100 cm².

[0114] In Experiment B, polyisobutylene and polybutene oil with a number average molecular weight of 1200 were added and dispersed and mixed at 90°C for 6 minutes. The compound was then degassed under a vacuum of 0.08 MPa for 5 minutes and calendered, with the adhesive layer thickness controlled at 3.5 mm ± 0.1 mm. After molding, 5 air bubbles were visible per 100 cm².

[0115] Experiment C involved adding polyisobutylene and polybutene oil with a number average molecular weight of 2400 at 110℃, dispersing and mixing for 12 minutes, then degassing under a vacuum of 0.095 MPa for 15 minutes, followed by calendering. The adhesive layer thickness was controlled at 3.5 mm ± 0.1 mm. After molding, two bubble defects were visible per 100 cm².

[0116] All three sets of rubber compounds were subjected to subsequent performance tests using the same molding method and the same rubber layer thickness.

[0117] 7. Performance Testing

[0118] Puncture seal performance test: Three sets of rubber compounds were applied to the inner wall area of ​​the tire crown. After the tire was inflated to 250 kPa, a 3 mm diameter steel nail was inserted into the crown area, held for 10 minutes, and then removed. The tire pressure loss over 24 hours was recorded. The test was then repeated using a 6 mm diameter steel nail.

[0119] In Experiment A, the tire pressure loss after 24 hours of puncture by a 3mm steel nail was 4.5kPa, and the tire pressure loss after 24 hours of puncture by a 6mm steel nail was 13.2kPa.

[0120] Experiment B showed the lowest tire pressure loss. The tire pressure loss after 24 hours following a puncture by a 3mm steel nail was 2.6 kPa, while the loss after 24 hours following a puncture by a 6mm steel nail was 9.4 kPa. This indicates that the rubber compound filled the puncture more quickly.

[0121] Experiment C exhibited weaker puncture sealing performance compared to Experiments A and B. The tire pressure loss after 24 hours following a puncture by a 3mm steel nail was 6.2 kPa, while the loss after 24 hours following a puncture by a 6mm steel nail was 17.5 kPa. The rubber compound showed strong morphological stability, but the flow and filling speed at the puncture site was relatively slow.

[0122] High-temperature and high-speed stability test: Three sets of tires were re-inflated to 250 kPa and placed in a drum testing machine. The test speed was 120 km / h, and the running time was 2 hours. After the test, the tires were cut open, and the maximum displacement of the rubber layer and the local accumulation were measured.

[0123] The maximum displacement of the adhesive layer in Experiment A was 1.6 mm, and no obvious flanging was observed at the edge of the adhesive layer.

[0124] In Experiment B, the maximum displacement of the adhesive layer was 2.8 mm, with slight displacement at the edge and a local increase in build-up thickness of 0.6 mm. These results correspond to its higher porosity filling performance, indicating that increased fluidity leads to decreased high-temperature and high-speed stability.

[0125] The maximum displacement of the adhesive layer in Experiment C was 0.8 mm, the local accumulation thickness increased by 0.2 mm, and no obvious displacement was observed at the edge of the adhesive layer. It had the best morphological retention ability under high temperature, high speed and centrifugal action.

[0126] In summary, under the test conditions of this embodiment, Experiment A's puncture sealing performance and high-temperature, high-speed stability are between those of Experiments B and C, making it suitable for ordinary passenger car tires and daily commuter tires. Experiment B's 24-hour tire pressure loss is lower than that of Experiments A and C, making it suitable for high-risk usage scenarios such as low-speed short-distance travel, urban delivery, and two-wheeled electric vehicles. Experiment C's 120°C flow distance, maximum rubber layer displacement after drum rotation, and local build-up thickness are all lower than those of Experiments A and B, making it suitable for tire usage scenarios involving long high-speed driving times, high tire temperatures, or large load variations.

[0127] Three sets of experiments showed that adjustments to polyisobutylene (number average molecular weight 1200-2400), polybutene oil, composite confined fillers, and structured mixing conditions affect the performance distribution of the lining sealant between its porosity-filling properties and its high-temperature, high-speed morphological stability. The degree of pre-dispersion of the composite confined masterbatch, the intensity of the structured mixing, and the proportion of low molecular weight polyisobutylene and polybutene oil added all contribute to the balance between the sealant's porosity-filling properties and its high-temperature, high-speed morphological stability.

[0128] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A lining sealant for puncture-proof and explosion-proof tires, characterized in that, By weight percentage, including: Brominated butyl rubber 32%-38%; 7%-10% of polyisobutylene with a number average molecular weight of 90,000-150,000; Polyisobutylene with a number average molecular weight of 1200-2400 accounts for 17%-20% of the total content. Hydrogenated C5-C9 copolymer petroleum resin 20%-26%; Polybutene oil 4%-8%; Maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer 7%-11%; The composite confinement filler is 3%-6%; the composite confinement filler is composed of aminated aramid nanofibers and organically modified montmorillonite.

2. The lining sealant for puncture-proof and explosion-proof tires according to claim 1, characterized in that: The softening point of the hydrogenated C5-C9 copolymer petroleum resin is 110℃-125℃; the maleic anhydride grafting rate of the maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer is 1.0%-1.8%.

3. The lining sealant for puncture-proof and explosion-proof tires according to claim 1, characterized in that: The mass ratio of the aminated aramid nanofibers to the organically modified montmorillonite is 1:1.8-1:3; the amine value of the aminated aramid nanofibers is 0.6mmol / g-1.8mmol / g, and the aspect ratio is 80-300; the interlayer spacing of the organically modified montmorillonite is 1.8nm-3.2nm.

4. The inner lining sealant for puncture-proof and explosion-proof tires according to claim 1, characterized in that: The brominated butyl rubber is a brominated isobutylene-isoprene copolymer, and the mass percentage of bromine in the brominated butyl rubber is 1.6%-2.2%.

5. A method for preparing an inner lining sealant for puncture-resistant and explosion-proof tires, used to prepare the inner lining sealant for puncture-resistant and explosion-proof tires as described in any one of claims 1-4, characterized in that, include: S1. By mass percentage, weigh out 32%-38% brominated butyl rubber, 7%-10% polyisobutylene with a number average molecular weight of 90,000-150,000, 17%-20% polyisobutylene with a number average molecular weight of 1200-2400, 20%-26% hydrogenated C5-C9 copolymer petroleum resin, 4%-8% polybutene oil, 7%-11% maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer, and 3%-6% composite confinement filler; wherein the composite confinement filler is composed of aminated aramid nanofibers and organically modified montmorillonite. S2. After drying the composite confined filler, it is pre-dispersed and mixed with the maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer to obtain the composite confined masterbatch. S3. The brominated butyl rubber, the polyisobutylene with a number average molecular weight of 90,000-150,000 and the hydrogenated C5-C9 copolymer petroleum resin are plasticized and mixed to obtain a rubber resin base material. S4. The composite confined masterbatch is added to the rubber resin base material for structured mixing to obtain a rubber resin composite base material containing the composite confined masterbatch. S5. The polyisobutylene with a number average molecular weight of 1200-2400 and the polybutene oil are added to the rubber resin composite base containing the composite confined masterbatch for dispersion and mixing, and then degassing and molding are performed to obtain the inner lining sealant for puncture-proof and explosion-proof tires.

6. A method for preparing an inner lining sealant for puncture-proof and explosion-proof tires according to claim 5, characterized in that: The composite confined filler is obtained by premixing aminated aramid nanofibers and organically modified montmorillonite for 3-8 minutes; the organically modified montmorillonite is alkyl quaternary ammonium salt modified montmorillonite.

7. A method for preparing an inner lining sealant for puncture-proof and explosion-proof tires according to claim 5, characterized in that: The drying temperature of the composite confined packing is 80℃-100℃, and the time is 1h-2h; the temperature of the pre-dispersion mixing is 120℃-135℃, the time is 8min-15min, and the rotation speed is 40r / min-60r / min.

8. A method for preparing an inner lining sealant for puncture-proof and explosion-proof tires according to claim 5, characterized in that: The plasticizing and mixing process includes: first plasticizing the brominated butyl rubber for 3-6 minutes, then adding the polyisobutylene with a number average molecular weight of 90,000-150,000 and the hydrogenated C5-C9 copolymer petroleum resin and mixing for 8-14 minutes; the plasticizing and mixing temperature is 125℃-145℃.

9. A method for preparing an inner lining sealant for puncture-proof and explosion-proof tires according to claim 5, characterized in that: The structured mixing is a segmented feeding mixing process, in which the composite confined masterbatch is added to the rubber resin base material in two separate additions, with a time interval of 2 min to 5 min between the two additions; the structured mixing temperature is 120℃ to 140℃, the time is 8 min to 15 min, and the rotation speed is 45 r / min to 70 r / min.

10. A method for preparing an inner lining sealant for puncture-proof and explosion-proof tires according to claim 5, characterized in that: The dispersion and mixing temperature is 90℃-110℃, and the time is 6min-12min; the degassing is vacuum degassing with a vacuum degree of 0.08MPa-0.095MPa and a degassing time of 5min-15min; the molding is calendering or extrusion molding, and the thickness of the inner lining sealant after molding is 2.5mm-4.5mm.

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