Organic modified nano tire inner liner formula and preparation method thereof

Abstract

The invention discloses an organic modified nano tire inner liner formula and a preparation method thereof, and relates to the technical field of rubber tires. The formula comprises natural rubber, halogenated butyl rubber, carbon black, organic modified nano magnesium silicate, environment-friendly aromatic oil and various auxiliaries, the organic modified nano magnesium silicate is hydrated magnesium silicate modified through hydroxylation and silanization, the surface of the organic modified nano magnesium silicate is changed into hydrophobic from hydrophilic, and good combination and molecular intercalation with rubber can be achieved. The preparation method comprises two steps of master batch high-temperature mixing and final rubber low-temperature mixing. The modified nano magnesium silicate is introduced to partially replace carbon black, the basic performance of the inner liner is guaranteed, meanwhile, the gas permeability is remarkably reduced, the heat conductivity, stress at definite elongation and tensile strength are improved, the processing demolding performance is improved, the vulcanization defect is reduced, the production cost can be effectively reduced, and the method is suitable for industrial production of the car tire inner liner.

Description

Technical Field

[0001] This invention relates to the field of rubber tire technology, and more specifically, to an organic modified nano-tire airtight layer formulation and its preparation method. Background Technology

[0002] With the rapid development of the social economy and the explosive growth in demand for transportation infrastructure, the demand for automobile tires is increasing, and the performance requirements for tires are also becoming more stringent. Semi-steel radial tires are tubeless, therefore requiring a highly airtight air layer, meaning low gas permeability. Currently, most tire air layer designs achieve this by using butyl rubber with added carbon black. Simultaneously, some formulations add inorganic filler calcium carbonate to reduce costs. The butyl rubber used is mostly brominated butyl or chlorinated butyl, and the carbon black used is N660 with a larger particle size.

[0003] Hydrated magnesium silicate is a natural nanolayered silicate with a one-dimensional nanostructure and a large aspect ratio, effectively blocking gas permeation channels and thus providing excellent air permeation barrier properties. However, because hydrated magnesium silicate has a hydrophilic surface, it cannot bond well with rubber, thereby affecting the physical properties of rubber and limiting its use in large quantities. Summary of the Invention

[0004] To achieve optimal airtightness, improved thermal conductivity, and ease of demolding, while also considering cost, this invention utilizes organically modified nano-layered magnesium silicate hydrate (hereinafter referred to as modified magnesium silicate) to replace a portion of carbon black in the preparation of an airtight layer rubber for passenger car tires. This invention provides an organically modified nano-tire airtight layer formulation and its preparation method to address the problems mentioned in the background art.

[0005] In a first aspect, embodiments of this application provide an organically modified nano-tire airtight layer formulation, which, by weight, comprises the following components: Natural rubber 10-40 parts; halogenated butyl rubber 60-90 parts; carbon black 40-70 parts; organically modified nano-magnesium silicate 20-40 parts; environmentally friendly aromatic oil 8.0-15.0 parts; homogenizer 4.0-8.0 parts; zinc oxide 2.0-5.0 parts; magnesium oxide 0.2-0.6 parts; stearic acid 0.5-1.5 parts; antioxidant microcrystalline wax 0.5-1.0 parts; tackifying resin 1.0-3.0 parts; accelerator 0.5-1.5 parts; scorching inhibitor 0.10-0.25 parts; insoluble sulfur 0.5-1.0 parts; The total number of parts of the natural rubber and the halogenated butyl rubber is 100.

[0006] In some embodiments of this application, the organically modified nano-magnesium silicate is hydrated magnesium silicate that has undergone dual modification through hydroxylation and silanization, with a surface contact angle greater than 80° and an FTIR spectrum at 2920 cm⁻¹. -1 2850cm -1 and 1710cm -1 It has a characteristic absorption peak.

[0007] In some embodiments of this application, the hydroxylation process is as follows: hydrated magnesium silicate is added to a 30% sodium hydroxide solution, stirred continuously at 90°C for 6 hours, and after the reaction is completed, it is washed, centrifuged until neutral, and then vacuum dried at 80°C for 48 hours to obtain hydroxylated magnesium silicate. The silanization process is as follows: the hydroxylated magnesium silicate is dispersed in a mixed solvent consisting of 75 mL ethanol and 10 mL distilled water. The pH of the mixed solvent is adjusted to 5.0 with glacial acetic acid. After ultrasonic dispersion for 30 minutes, 20% of the mass of magnesium silicate silane coupling agent KH-570 is added. The mixture is stirred and reacted in a water bath at 85°C for 6 hours. After the reaction is completed, the mixture is centrifuged, washed with anhydrous ethanol, and vacuum dried at 80°C for 24 hours to obtain the organically modified nano magnesium silicate.

[0008] In some embodiments of this application, the halogenated butyl rubber is at least one of brominated butyl rubber and chlorinated butyl rubber; the carbon black is N660 carbon black.

[0009] In some embodiments of this application, zinc oxide and magnesium oxide are added in the form of natural rubber masterbatch with effective contents of 80% and 70%, respectively.

[0010] In some embodiments of this application, the accelerator is selected from accelerator DM, accelerator TBBS, and accelerator MBTS.

[0011] In some embodiments of this application, the anti-scorching agent is CTP; the insoluble sulfur is a high-thermal-stability insoluble sulfur, and the insoluble sulfur content remains not less than 75% at 105°C.

[0012] Secondly, embodiments of this application provide a method for preparing an organically modified nano-tire airtight layer formulation, comprising the following steps: S1: Masterbatch preparation: Natural rubber, halogenated butyl rubber, carbon black, organic modified nano magnesium silicate, antioxidant, zinc oxide and stearic acid are added to the internal mixer in sequence and mixed under a pressure of 0.4 to 0.6 MPa. Then environmentally friendly aromatic oil is added and the mixing temperature is controlled at 125 to 150℃. After mixing to the set temperature, the rubber is discharged. S2: Final rubber preparation: Mix the masterbatch with accelerator, anti-scorching agent and insoluble sulfur in an internal mixer, control the mixing temperature to not exceed 105℃, and discharge the rubber after uniform mixing.

[0013] In some embodiments of this application, in S1, the rotation speed of the internal mixer is set to 40-50 rpm, and the total mixing time is 90-130 seconds; In step S2, the internal mixer speed is set to 30-50 rpm, and the total mixing time is 70-100 seconds.

[0014] Compared with the prior art, the beneficial effects of the present invention are: 1. By partially replacing carbon black with organically modified magnesium silicate with a one-dimensional nano-layered structure, gas permeation channels can be effectively blocked, gas permeability can be reduced, thereby significantly improving the airtightness of the tire and extending the pressure holding time.

[0015] 2. The introduction of modified magnesium silicate improves the thermal conductivity of the rubber compound and enhances the heat transfer efficiency during the vulcanization process, which helps to shorten the vulcanization time and increase production pace and capacity.

[0016] 3. The lubricating effect of magnesium silicate makes it easier for the rubber compound to separate from the capsule after vulcanization, reducing demolding adhesion defects, reducing the amount of release agent used, and improving surface quality and production efficiency.

[0017] 4. Modified magnesium silicate bonds firmly with the rubber matrix, significantly improving the tensile stress, tensile strength, and gamma strength of the rubber compound, reducing the tensile deformation of semi-finished products during the molding process, and improving the dimensional uniformity and durability of tires.

[0018] 5. The nano-intercalation structure enhances the flexibility and resistance to flexural cracking of the rubber compound, which helps to improve the lifespan of the tire under dynamic usage conditions.

[0019] 6. Replacing carbon black with lower-priced modified magnesium silicate can effectively reduce raw material costs while maintaining performance. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0021] Figure 1 A flow chart of the organic-modified nano-magnesium silicate preparation process provided by the present invention; Figure 2 Schematic diagrams showing the surface properties and structure of magnesium silicate before and after modification, provided by this invention; Figure 3 The process flow diagram for preparing tire airtight layer rubber material provided by the present invention; Figure 4 A comparative schematic diagram of the gas barrier mechanism of the airtight layer provided by the present invention; Figure 5 A bar chart comparing key performance data of embodiments and comparative examples provided by the present invention. Detailed Implementation

[0022] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] To enable those skilled in the art to better understand the present application, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] See Figure 1 As shown in the flowchart, the organic-modified nano-magnesium silicate preparation process provided by this invention clearly illustrates its two-step core process. The first step is hydroxylation treatment: hydrated magnesium silicate is reacted in a 30% sodium hydroxide solution at 90°C for 6 hours, and after washing and drying, an intermediate rich in hydroxyl groups is obtained. The second step is silanization treatment: hydroxylated magnesium silicate is dispersed in an ethanol-water system, the pH is adjusted to 5.0, and 20% by mass of silane coupling agent KH-570 is added. The mixture is reacted at 85°C for 6 hours, and finally, after washing and drying, organic-modified nano-magnesium silicate is obtained.

[0025] In fact, the surface modification mechanism involves the full activation of silanols (Si-OH) on the surface of hydrated magnesium silicate under alkaline conditions. These silanols (Si-OH) react with those generated from the hydrolysis of KH-570 to form stable Si-O-Si covalent bonds, thus achieving the chemical grafting of organic long chains onto the surface of inorganic fillers. This process not only imparts hydrophobicity to the filler, but the terminal methacryloyloxy groups (C=C) can also participate in the crosslinking network of the rubber during vulcanization, further enhancing interfacial bonding.

[0026] Specifically, organically modified nano-magnesium silicate is prepared through the following steps: Surface hydroxylation treatment: Take 10g of hydrated magnesium silicate and add it to 250mL of 30% sodium hydroxide solution. Place it in a three-necked flask and stir vigorously at 90℃ for 6 hours to ensure complete surface hydroxylation. After the reaction is complete, cool the sample, wash it repeatedly with distilled water until neutral, and centrifuge. Place the obtained sample in an 80℃ vacuum drying oven and dry for 48 hours to obtain hydroxylated magnesium silicate.

[0027] Silanization treatment: 10g of hydroxylated magnesium silicate was added to a three-necked flask containing 75mL of ethanol and 10mL of distilled water. The pH of the solution was adjusted to approximately 5.0 with glacial acetic acid, followed by ultrasonic dispersion for 30 minutes to ensure uniform dispersion of the filler. 2g of silane coupling agent KH-570 (20% of the magnesium silicate mass) was added, and the mixture was stirred vigorously in an 85℃ water bath for 6 hours. After the reaction was completed, the mixture was cooled to room temperature, centrifuged, and washed three times with anhydrous ethanol to remove unreacted coupling agent. Finally, the sample was vacuum dried at 80℃ for 24 hours to obtain organically modified nano-magnesium silicate.

[0028] Magnesium silicate modified by the above process has an FTIR spectrum at 2920 cm⁻¹. -1 2850cm -1 (CH stretching vibration) and 1710cm -1 The presence of a characteristic absorption peak at the (C=O stretching vibration) indicates successful grafting of KH-570. Contact angle testing shows that the surface contact angle increased from approximately 25° (hydrophilic) before modification to over 85° (hydrophobic). TEM observations indicate that the material maintains a one-dimensional nanolayered structure with a moderately increased interlayer spacing, which is beneficial for rubber molecule intercalation.

[0029] See Figure 2 As shown in the schematic diagram of the surface properties and structure of magnesium silicate before and after modification provided by the present invention, the key changes of hydrated magnesium silicate before and after organic modification are intuitively illustrated.

[0030] The left side shows the unmodified state: the surface of hydrated magnesium silicate is rich in hydrophilic hydroxyl groups (-OH), and its contact angle is about 25°, exhibiting obvious hydrophilicity; The right side shows the modified state: after KH-570 silanization treatment, organic long chains are grafted onto the surface of magnesium silicate, the contact angle increases to more than 85°, and it is transformed into a hydrophobic surface.

[0031] See Figure 3 As shown in the diagram, the tire airtight layer rubber compound preparation process provided by this invention clearly illustrates the core process flow of the two-step mixing method. The method includes: a first stage (masterbatch production), in which rubber base material, carbon black, organically modified nano-magnesium silicate, and processing aids are mixed at a high temperature of 140-150℃ to obtain masterbatch; and a second stage (final rubber production), in which the masterbatch is mixed with a vulcanization system (accelerator, scorching inhibitor, and insoluble sulfur) at a controlled low temperature of ≤105℃ to obtain the final rubber compound.

[0032] It should be further explained that the masterbatch mixing stage is crucial for achieving sufficient dispersion of fillers and rubber intercalation. Maintaining the mixing temperature at 140-150℃ for a certain period provides sufficient thermodynamic motive force for the interlayer expansion of magnesium silicate and the embedding of rubber molecular chains. Too low a temperature will result in incomplete intercalation, while too high a temperature may lead to rubber degradation.

[0033] In the final mixing stage, the vulcanization system is uniformly incorporated at a low temperature (≤105℃). Strict temperature control is crucial to prevent scorching of the rubber compound and to ensure that the vulcanization reaction occurs within the mold cavity rather than the internal mixer. Increasing the rotation speed (to 50 rpm) aims to ensure uniform mixing while completing the mixing process as quickly as possible to control temperature rise.

[0034] Example 1 A tire airtight layer formulation using organic modified nano-silicate filler with high brominated butyl rubber content comprises the following components in parts by weight: 15 parts natural rubber, 85 parts brominated butyl rubber, 40 parts N660 carbon black, 30 parts modified magnesium silicate, 12.0 parts environmentally friendly aromatic oil, 7.0 parts homogenizer, 4.0 parts zinc oxide, 0.4 parts magnesium oxide, 1.0 part stearic acid, 0.5 parts antioxidant microcrystalline wax, 1.0 part octylphenol tackifying resin, 1.5 parts accelerator MBTS, 0.15 parts anti-scorching agent, and 0.7 parts insoluble sulfur.

[0035] This embodiment describes a method for preparing a tire airtight layer using organically modified nano-silicate fillers, comprising the following steps: S1: Masterbatch Production: Add natural rubber, brominated butyl rubber, antioxidant, zinc oxide, and stearic acid sequentially to the internal mixer, pressing down the top plug at a pressure of 0.4-0.6 MPa. After 20 seconds, raise the plug, add carbon black and modified magnesium silicate, pressing down the top plug at a pressure of 0.4-0.6 MPa. After 40 seconds, raise the plug, hold for 10 seconds, add environmentally friendly aromatic oil, pressing down the top plug at a speed of 40-45 rpm. When the mixing temperature reaches 125℃, raise the plug, hold for 10 seconds, press down the top plug, and after the mixing temperature rises to 140℃, increase the speed to 50 rpm to discharge the rubber.

[0036] S2: Final Rubber Production: Add masterbatch, accelerator DM, scorch inhibitor CTP, and insoluble sulfur to the internal mixer. Set the speed to 30-45 rpm, press down the top plug, and the pressure of the top plug is 0.4-0.6 MPa. After 35 seconds, raise the plug, hold for 10 seconds, and then press down the top plug again, with the pressure of the top plug remaining at 0.4-0.6 MPa. After 35 seconds, raise the plug again, hold for 10 seconds, and then press down the top plug again, with the pressure of the top plug remaining at 0.4-0.6 MPa. Raise the mixing temperature to 105℃, increase the speed to 50 rpm, and discharge the rubber.

[0037] S2: Final Rubber Production: Add masterbatch, accelerator DM, scorch inhibitor CTP, and insoluble sulfur to the internal mixer. Set the speed to 30-45 rpm, press down the top plug, and the pressure of the top plug is 0.4-0.6 MPa. After 35 seconds, raise the plug, hold for 10 seconds, and then press down the top plug again, with the pressure of the top plug remaining at 0.4-0.6 MPa. After 35 seconds, raise the plug again, hold for 10 seconds, and then press down the top plug again, with the pressure of the top plug remaining at 0.4-0.6 MPa. Raise the mixing temperature to 105℃, increase the speed to 50 rpm, and discharge the rubber.

[0038] Example 2 A tire airtight layer formulation with low chlorinated butyl rubber content using organic modified nano-silicate filler, comprising the following components in parts by weight: 35 parts natural rubber, 65 parts chlorinated butyl rubber, 40 parts N660 carbon black, 30 parts modified magnesium silicate, 12.0 parts environmentally friendly aromatic oil, 7.0 parts homogenizer, 4.0 parts zinc oxide, 0.4 parts magnesium oxide, 1.0 part stearic acid, 0.5 parts antioxidant microcrystalline wax, 1.0 part octylphenol tackifying resin, 1.5 parts accelerator MBTS, 0.15 parts anti-scorching agent, and 0.7 parts insoluble sulfur.

[0039] This embodiment describes a method for preparing a tire airtight layer using organically modified nano-silicate fillers, comprising the following steps: S1: Masterbatch Production: Add natural rubber, chlorinated butyl rubber, antioxidant, zinc oxide, and stearic acid sequentially to the internal mixer, pressing down the top plug at a pressure of 0.4-0.6 MPa. After 20 seconds, raise the plug, add carbon black and modified magnesium silicate, pressing down the top plug at a pressure of 0.4-0.6 MPa. After 40 seconds, raise the plug, hold for 10 seconds, add environmentally friendly aromatic oil, pressing down the top plug at a speed of 40-45 rpm. When the mixing temperature reaches 125℃, raise the plug, hold for 10 seconds, press down the top plug, and after the mixing temperature rises to 145℃, increase the speed to 50 rpm to discharge the rubber.

[0040] S2: Final Rubber Production: Add masterbatch, accelerator DM, scorch inhibitor CTP, and insoluble sulfur to the internal mixer. Set the speed to 30-45 rpm, press down the top plug, and the pressure of the top plug is 0.4-0.6 MPa. After 35 seconds, raise the plug, hold for 10 seconds, and then press down the top plug again, with the pressure of the top plug remaining at 0.4-0.6 MPa. After 35 seconds, raise the plug again, hold for 10 seconds, and then press down the top plug again, with the pressure of the top plug remaining at 0.4-0.6 MPa. Raise the mixing temperature to 105℃, increase the speed to 50 rpm, and discharge the rubber.

[0041] Comparative Example 1 A tire airtight layer formulation with high brominated butyl rubber content using carbon black filler, comprising the following components in parts by weight: 15 parts natural rubber, 85 parts brominated butyl rubber, 75 parts N660 carbon black, 11.0 parts environmentally friendly aromatic oil, 6.0 parts homogenizer, 4.0 parts zinc oxide, 0.4 parts magnesium oxide, 1.0 part stearic acid, 0.5 parts antioxidant microcrystalline wax, 1.0 part octylphenol tackifying resin, 1.5 parts accelerator MBTS, 0.15 parts anti-scorching agent, and 0.7 parts insoluble sulfur.

[0042] This comparative example describes a method for preparing a high-brominated butyl rubber content tire airtight layer using carbon black filler, comprising the following steps: S1: Masterbatch Production: Add natural rubber, brominated butyl rubber, antioxidant, zinc oxide, and stearic acid sequentially to the internal mixer, pressing down the top plug at a pressure of 0.4-0.6 MPa. After 20 seconds, raise the plug, add carbon black, and press down the top plug at a pressure of 0.4-0.6 MPa. After 40 seconds, raise the plug, hold for 10 seconds, add environmentally friendly aromatic oil, and press down the top plug at a speed of 40-45 rpm. When the mixing temperature reaches 125℃, raise the plug and hold for 10 seconds. Press down the top plug, and after the mixing temperature rises to 140℃, increase the speed to 50 rpm to discharge the rubber.

[0043] S2: Final Rubber Production: Add masterbatch, accelerator DM, scorch inhibitor CTP, and insoluble sulfur to the internal mixer. Set the speed to 30-45 rpm, press down the top plug, and the pressure of the top plug is 0.4-0.6 MPa. After 35 seconds, raise the plug, hold for 10 seconds, and then press down the top plug again, with the pressure of the top plug remaining at 0.4-0.6 MPa. After 35 seconds, raise the plug again, hold for 10 seconds, and then press down the top plug again, with the pressure of the top plug remaining at 0.4-0.6 MPa. Raise the mixing temperature to 105℃, increase the speed to 50 rpm, and discharge the rubber.

[0044] Comparative Example 2 A tire airtight layer formulation with low chlorinated butyl rubber content using carbon black filler, comprising the following components in parts by weight: 35 parts natural rubber, 65 parts chlorinated butyl rubber, 75 parts N660 carbon black, 11.0 parts environmentally friendly aromatic oil, 6.0 parts homogenizer, 4.0 parts zinc oxide, 0.4 parts magnesium oxide, 1.0 part stearic acid, 0.5 parts antioxidant microcrystalline wax, 1.0 part octylphenol tackifying resin, 1.5 parts accelerator MBTS, 0.15 parts anti-scorching agent, and 0.7 parts insoluble sulfur.

[0045] This embodiment describes a method for preparing a tire airtight layer with low chlorinated butyl rubber content using carbon black filler, comprising the following steps: S1: Masterbatch Production: Add natural rubber, chlorinated butyl rubber, antioxidant, zinc oxide, and stearic acid sequentially to the internal mixer, pressing down the top plug at a pressure of 0.4-0.6 MPa. After 20 seconds, raise the plug, add carbon black, and press down the top plug at a pressure of 0.4-0.6 MPa. After 40 seconds, raise the plug, hold for 10 seconds, add environmentally friendly aromatic oil, and press down the top plug at a speed of 40-45 rpm. When the mixing temperature reaches 125℃, raise the plug and hold for 10 seconds. Press down the top plug, and after the mixing temperature rises to 145℃, increase the speed to 50 rpm to discharge the rubber.

[0046] S2: Final Rubber Production: Add masterbatch, accelerator DM, scorch inhibitor CTP, and insoluble sulfur to the internal mixer. Set the speed to 30-45 rpm, press down the top plug, and the pressure of the top plug is 0.4-0.6 MPa. After 35 seconds, raise the plug, hold for 10 seconds, and then press down the top plug again, with the pressure of the top plug remaining at 0.4-0.6 MPa. After 35 seconds, raise the plug again, hold for 10 seconds, and then press down the top plug again, with the pressure of the top plug remaining at 0.4-0.6 MPa. Raise the mixing temperature to 105℃, increase the speed to 50 rpm, and discharge the rubber.

[0047] The physical properties of Embodiments 1-2 and Comparative Examples 1-2 of the present invention are shown in Table 1; Table 1 ; As shown in Table 1, using 30 parts of organically modified nano-magnesium silicate can improve the flexural properties, tensile modulus, and thermal conductivity of the tire airtight layer formulation, while reducing gas permeability. The increase in the compound's Tg is due to the bonding and nano-intercalation of the nanomaterials with the rubber; this small increase will not affect the tire's use in cold regions.

[0048] As shown in Table 1, the improvements in various properties do not exist in isolation. For example, the increase in tensile stress and tensile strength directly enhances the dimensional stability and deformation resistance of the airtight layer during tire molding, reducing the problem of uneven thickness of the airtight layer caused by the stretching of semi-finished products. The improvement in thermal conductivity and the reduction in vulcanization time constitute a complete synergistic chain from rubber compound formulation to vulcanization process.

[0049] See Figure 4The diagram shows a comparison of the gas barrier mechanism of the airtight layer provided by this invention. The left side shows the traditional carbon black filler system: carbon black aggregates form a relatively loose structure with many straight interfaces in the rubber compound, resulting in a relatively straight gas permeation path (as shown by the arrows) with low tortuosity, leading to high gas permeability. The right side shows the modified nano-magnesium silicate filler system of this invention: its unique nanosheet structure is oriented or interlaced in the rubber compound, forming a dense and tortuous "maze-like" physical barrier network together with the intercalated rubber molecules. The gas permeation path (as shown by the arrows) is significantly lengthened and forced to frequently detour, thereby greatly increasing the gas diffusion resistance.

[0050] The performance of Examples 1-2 and Comparative Examples 1-2 on the test tires is shown in Table 2; Table 2 ; As can be seen from the test results in Table 2, 30 parts of organically modified nano-magnesium silicate can meet the basic performance requirements of tires, while reducing the tire pressure loss rate and improving the tire's air tightness.

[0051] See Figure 5 As shown in the bar chart comparing the key performance data of the embodiments and comparative examples provided by this invention, the significant improvement in the key performance of the tire airtight layer compound after partially replacing carbon black with organically modified nano-magnesium silicate is intuitively quantified. The chart selects four of the most representative performance indicators for comparison: gas permeability, 300% tensile stress, tensile strength, and thermal conductivity. As shown in the figure, compared with the traditional carbon black filler formulation (comparative example), the formulation of this invention (example) shows clear advantages in all indicators: the gas permeability is significantly reduced, directly confirming the core improvement in airtightness; the 300% tensile stress and tensile strength are simultaneously increased, reflecting the enhanced rigidity and strength of the compound; and the increased thermal conductivity confirms the optimization of thermal conductivity.

[0052] It should be further explained that the one-dimensional nanolayered structure of magnesium silicate gives it an extremely large specific surface area and aspect ratio. After modification, the interlayer spacing is moderately increased (as can be detected by XRD, where the characteristic peaks shift to smaller angles), providing space for the intercalation of rubber molecular chains. This "nano-intercalated composite" structure can form a continuous and tortuous physical barrier network in the rubber compound, which is the fundamental reason for the significant improvement in airtightness.

[0053] The pressure, time, rotation speed, and temperature ranges provided by this invention are optimized windows determined based on extensive experimentation. Following this process, production on internal mixers of different specifications can yield rubber compounds with stable performance and good repeatability, meeting the requirements of industrial production.

[0054] The above description is merely two embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

[0055] In conclusion, the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An organomodified nanotire innerliner formulation, characterized in that, The following components are included by weight parts: Natural rubber 10-40 parts; halogenated butyl rubber 60-90 parts; carbon black 40-70 parts; organically modified nano-magnesium silicate 20-40 parts; environmentally friendly aromatic oil 8.0-15.0 parts; uniform agent 4.0-8.0 parts; zinc oxide 2.0-5.0 parts; magnesium oxide 0.2-0.6 parts; stearic acid 0.5-1.5 parts; anti-aging agent microcrystalline wax 0.5-1.0 parts; tackifying resin 1.0-3.0 parts; accelerator 0.5-1.5 parts; anti-scorching agent 0.10-0.25 parts; insoluble sulfur 0.5-1.0 parts; The total parts of the natural rubber and the halogenated butyl rubber are 100 parts.

2. An organomodified nanotire innerliner formulation according to claim 1, characterized in that, The organic modified nanometer magnesium silicate is prepared by double modification of hydroxylation and silanization from hydrated magnesium silicate, has a surface contact angle greater than 80°, and has characteristic absorption peaks at 2920 cm -1 , 2850 cm -1 , and 1710 cm -1 in an FTIR spectrum.

3. An organomodified nanotire innerliner formulation and method of making thereof according to claim 2, wherein, The method of hydroxylation and silanization modification is specifically: The treatment method of hydroxylation is: adding hydrated magnesium silicate into a 30% sodium hydroxide solution, continuously stirring at 90℃ for 6 hours, washing, centrifuging to neutral after the reaction is completed, and vacuum drying at 80℃ for 48 hours to obtain hydroxylated magnesium silicate; The treatment method of silanization is: dispersing the hydroxylated magnesium silicate in a mixed solvent composed of 75mL ethanol and 10mL distilled water, adjusting the pH of the mixed solvent to 5.0 with glacial acetic acid, ultrasonic dispersion for 30 minutes, then adding 20% silane coupling agent KH-570 based on the mass of magnesium silicate, stirring and reacting in a 85℃ water bath for 6 hours, centrifuging, washing with anhydrous ethanol, and vacuum drying at 80℃ for 24 hours after the reaction is completed to obtain the organically modified nano-magnesium silicate.

4. An organomodified nanotire innerliner formulation and method of making thereof according to claim 1, wherein, The halogenated butyl rubber is at least one of brominated butyl rubber and chlorinated butyl rubber; the carbon black is N660 carbon black.

5. An organomodified nanotire innerliner formulation and method of making thereof according to claim 1, wherein, The zinc oxide and the magnesium oxide are added in the form of natural rubber masterbatch with effective contents of 80% and 70%, respectively.

6. An organomodified nanotire innerliner formulation and method of making thereof according to claim 1, wherein, The accelerator is selected from accelerator DM, accelerator TBBS, and accelerator MBTS.

7. An organomodified nanotire skrim formula and method of making thereof according to claim 1, wherein, The anti-scorching agent is anti-scorching agent CTP; the insoluble sulfur is high-thermal-stability insoluble sulfur with thermal stability keeping insoluble at 105℃ and sulfur content not less than 75%.

8. A method of preparing an organic modified nanotire air barrier formulation, characterized in that, The following steps are included: S1: masterbatch preparation: sequentially adding natural rubber, halogenated butyl rubber, carbon black, organically modified nano-magnesium silicate, anti-aging agent, zinc oxide, and stearic acid into an internal mixer, mixing under a pressure of 0.4-0.6MPa, then adding environmentally friendly aromatic oil, controlling the mixing temperature at 125-150℃, and discharging after mixing to the set temperature; S2: final batch preparation: mixing the masterbatch with accelerator, anti-scorching agent, and insoluble sulfur in an internal mixer, controlling the mixing temperature not to exceed 105℃, and discharging after uniform mixing.

9. An organomodified nanotire skrim formula and method of making thereof according to claim 8, wherein, In the S1, the rotating speed of the internal mixer is set to 40-50rpm, and the total mixing time is 90-130 seconds; In the S2, the rotating speed of the internal mixer is set to 30-50rpm, and the total mixing time is 70-100 seconds.

10. A tire innerliner characterized by, The one kind of organically modified nano-tire air layer formula and the one kind of organically modified nano-tire air layer formula are prepared by the preparation method.

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