Low-heat-generation high-temperature-resistant base rubber composition, mixing method and tire

Abstract

The invention relates to the technical field of tire rubber manufacturing, and discloses a low-heat-generation high-temperature-resistant base rubber composition which is prepared by mixing the following raw materials in parts by weight: 65-80 parts of rubber, 30-55 parts of filler A, 3.5-8.5 parts of an activating agent, 3-5 parts of a vulcanizing agent, 1.5-4 parts of an anti-aging agent, 0.5-1.5 parts of tear-resistant resin and 20-45 parts of a nano reinforced composite material, 0.5 to 2 parts of microcrystalline wax, and 0.01 to 0.3 part of scorch retarder CTP; the nano reinforced composite material is prepared by mixing natural rubber, a filler B, organic sulfide and dihydrazide. Through non-homogeneous distribution of the filler, the nano reinforced composite material can absorb a large amount of energy in the stretching process, so that the damage resistance and the high-temperature performance of the rubber material are improved; the dihydrazide enhances the chemical bonding between the nano reinforced composite material and the natural rubber, and reacts with aldehyde groups, carboxyl groups, carbonyl groups and other groups at the tail end of the rubber, so that the activity of the tail end of a free radical is reduced, and the heat generation is reduced.

Description

Technical Field

[0001] This invention relates to the field of tire rubber manufacturing technology, and more specifically, to a low-heat-generating, high-temperature-resistant base rubber composition, a mixing method, and a tire. Background Technology

[0002] Tires undergo cyclic compression-rebound-shear deformation during operation, especially at high speeds or under high loads. The dynamic excitation frequency of tire structural components can reach high levels, and the rubber material inevitably experiences hysteresis due to viscoelasticity, which is converted into heat. The base rubber, as one of the important rubber components inside the tire, is usually located adjacent to load-bearing structures such as the carcass and belt layers. It plays a role in stress transmission, deformation buffering, structural stability, and protection of the reinforcing material. The base rubber needs to possess sufficient modulus and tear resistance to inhibit structural fatigue and shoulder damage, while simultaneously minimizing heat generation and accumulation to avoid accelerated thermal aging, mechanical performance degradation, and early failure due to localized temperature rise. Therefore, for high-temperature (e.g., 60–80°C or even higher localized temperatures) dynamic conditions, achieving a synergistic improvement in "low heat generation + high-temperature resistance maintenance" while ensuring mechanical reinforcement and processing operability remains a key technical problem to be solved in tire base rubber formulation and process design.

[0003] To reduce the internal temperature rise of tires, a typical approach in existing technologies is to improve the thermal conductivity of the rubber compound to promote heat conduction and dissipation, thereby reducing heat accumulation. For example, Chinese patent document CN105384975A ​​discloses a low-heat-generating, high-thermal-conductivity engineering giant tire base rubber material and its preparation method. The formulation uses submicron-sized inorganic thermally conductive fillers combined with carbon nanotube bundles, and introduces components such as silane coupling agents. The base rubber composite material is prepared through processes such as intensive mixing, multiple feeding, and hot remelting, aiming to improve the internal thermal conductivity of the tire, reduce heat accumulation, and extend its service life. This approach is representative of the "enhanced thermal conductivity - reduced heat accumulation" path, but its focus is more on improving thermal conductivity to achieve cooling by using a high thermal conductivity filler system. In practical applications, high dosage of inorganic thermally conductive fillers often leads to problems such as increased formulation density, increased processing viscosity, and increased difficulty in controlling dispersion and interfacial compatibility. At the same time, "enhancing thermal conductivity" is not necessarily equivalent to "improving high-temperature modulus retention and reducing hysteresis loss". Under high-temperature dynamic deformation conditions, it may still face the challenge of balancing mechanical retention and low heat generation.

[0004] Another common approach to reducing heat generation focuses on designing reinforcements to improve filler dispersion and interfacial coupling. This involves improving filler-rubber interactions and reducing filler agglomeration and interfacial slippage to decrease hysteresis losses. For example, Chinese patent document CN116144084B discloses a low-heat-generating tire sidewall rubber composition and its mixing method. This composition uses a natural rubber / butadiene rubber blend system, introduces highly dispersible silica and silane coupling agents, and further adds specific reactive compounds to enhance the reactivity of silane and rubber double bonds, thereby strengthening the bond between silica and silane, and between silane and rubber. This alleviates the agglomeration problem of silica in the rubber and achieves a low-heat-generating effect while maintaining fatigue performance. This type of technology emphasizes reducing hysteresis loss through "filler dispersion and chemical coupling," which has practical significance in reducing heat generation. However, its main application is in components such as tire sidewalls, and its core lies in improving the interfacial chemistry of the silica system. For the modulus maintenance of the base rubber at higher temperature levels and the synergistic optimization of stronger high-temperature mechanical stability and lower hysteresis loss under specific filler systems, more targeted design is still needed, taking into account the working environment, stress state, and material structure of the base rubber.

[0005] In addition, existing technologies also improve the overall performance of tire component rubber compositions or the properties related to reinforcing materials by introducing hydrazide / diacylhydrazine compounds into the natural rubber matrix. For example, Chinese patent document CN102257055A relates to a rubber composition for tire components that do not come into contact with air or the gas being filled. It is based on natural rubber and contains reinforcing fillers and diacylhydrazine components to meet the comprehensive requirements of tire components in terms of stiffness, cohesion, and adhesion. This type of approach suggests that diacylhydrazine components can participate in the chemical action of the rubber system and affect the structure and properties of the rubber compound. However, its technical focus is more on the adhesion and overall balance of tire components (especially in areas related to the composite of reinforcing elements), and it does not provide a structural solution centered on nano-reinforcement and interfacial synergy for the "low heat generation and high-temperature mechanical retention" of the base rubber under high-temperature dynamic conditions. At the same time, existing disclosures still lack clear and directly reproducible systematic designs on how to achieve stable dispersion of nanofillers in an engineering-feasible mixing process and how to construct micro-reinforcing structures that are conducive to maintaining high-temperature modulus and reducing hysteresis loss.

[0006] In summary, while existing technologies offer several solutions from the perspectives of improving thermal conductivity, enhancing the coupling between silica-silane-rubber interfaces to reduce heat generation, and introducing dihydrazide compounds into natural rubber systems to improve the overall performance of components, they still generally have the following shortcomings or room for improvement: First, solutions relying solely on high thermal conductivity inorganic filler systems may impose processing and formulation burdens, and do not focus sufficiently on the synergistic improvement of "high-temperature modulus retention and hysteresis loss reduction"; Second, filler dispersion / coupling modification schemes for low heat generation are often geared towards components such as treads or sidewalls. When applied to the high-temperature load-bearing and buffering scenarios of the base rubber, the issue of mechanical attenuation and deformation amplification of the base rubber at high temperatures needs further consideration; Third, although dihydrazide compounds have been disclosed in tire rubber compositions, how to synergize with interfacial components such as nano-reinforcing fillers and organosilicon polysulfides to construct stable and effective reinforcing microstructures through industrially feasible mixing routes to suppress deformation, reduce hysteresis loss, and achieve low heat generation under high-temperature conditions still requires the development of comprehensive technical solutions that better meet the needs of the base rubber. Therefore, there is an urgent need for a rubber composition and its mixing method that can simultaneously achieve low heat generation and improved high-temperature resistance under feasible process conditions, and is designed for high-temperature dynamic working conditions of tire base rubber. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a low-heat-generating, high-temperature-resistant base rubber composition. This composition improves the modulus and mechanical properties of the rubber composition at high temperatures by using non-uniform distribution of fillers and nano-reinforced composite materials, thereby reducing the deformation of the rubber composition at high temperatures and reducing hysteresis loss.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: A low-heat-generating, high-temperature-resistant base rubber composition, wherein the rubber composition is prepared by mixing raw materials comprising the following components in parts by weight: Rubber A 65-80 parts, Packing material A: 30-55 parts Activator 3.5-8.5 parts, 2.0-5.0 parts of vulcanizing agent, Anti-aging agent 1.5-4.0 parts, 20-45 parts of nano-reinforced composite material The rubber A is natural rubber and / or synthetic isoprene rubber, and the filler A is carbon black and / or silica. The nano-reinforced wear-resistant composite material is prepared by mixing raw materials comprising the following components in parts by weight: Rubber B 20-40 parts, Packing material B: 1.0-10 parts 1-4 parts of organosilicon polysulfides 0.4-2 parts of diacylhydrazide compound; Rubber B is selected from butadiene rubber and / or natural rubber; the total weight of rubber A + rubber B is 100 parts by weight, and the filler B is one or more of carbon nanotubes, graphene, and nano carbon black.

[0009] Preferably, the rubber composition is prepared by mixing raw materials comprising the following components in parts by weight: Rubber A 70-78 parts, Packing material A, 35-45 parts. Activator 4.0-6.5 parts, 2.5-3.5 parts of vulcanizing agent, Anti-aging agent 2.0-3.5 parts, 25-40 parts of nano-reinforced composite material The nano-reinforced wear-resistant composite material is prepared by mixing raw materials comprising the following components in parts by weight: Rubber B 20-35 parts, Packing material B: 2.0-5.0 parts. 1-2.5 parts of organosilicon polysulfides, 0.5-1.5 parts of dihydrazide compound.

[0010] Preferably, the carbon black in filler A is one or two of N375, N330, N339, N347, and N326.

[0011] Preferably, the carbon nanotubes in filler B are arrayed, the carbon black is N375, N330, N339, N347 or N326, and the graphene is 2-10 layers of graphene oxide.

[0012] Preferably, the organosilicon polysulfide is selected from one or more of γ-mercaptopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, bis(3-mercaptopropyl)tetrasulfide, bis(3-mercaptopropyl)disulfide, mercaptoethyltriethoxysilane, mercaptopropylsiloxane copolymer, methylthiol silane, dimercaptoethylsilane, tetra(mercaptopropyl)silane, and bis(γ-triethoxysilylpropyl)sulfide.

[0013] Preferably, the activator is selected from one or more of zinc oxide, stearic acid, and zinc stearate.

[0014] Preferably, the antioxidant is selected from one or more of antioxidant 4010, antioxidant 4020, antioxidant RD, 2-mercaptobenzothiazole, and antioxidant TMQ; Preferably, the vulcanizing agent is selected from one or more of sulfur, dicumyl peroxide, vulcanization accelerator NS, vulcanization accelerator CZ, and tetramethylthiuram disulfide.

[0015] Preferably, the raw materials for the rubber composition also include 0.5-1.5 parts of tear-resistant resin, 0.5-2 parts of microcrystalline wax, and 0.01-0.3 parts of scorch inhibitor CTP.

[0016] Preferably, the tear-resistant resin is one or more of polycyclopentadiene resin, C5 modified resin, and C9 modified resin.

[0017] Preferably, the preparation method of the nano-reinforced wear-resistant composite material includes the following steps: starting the internal mixer, setting the speed to 30-45 rpm, adding natural rubber, filler and organosilicon polysulfide, mixing for 25-40 seconds, adding dihydrazide compound, continuing to mix for 1-2.5 minutes, discharging the glue, and obtaining the nano-reinforced composite material.

[0018] Furthermore, the present invention also provides a method for preparing the rubber composition, comprising the following steps: 1) First stage masterbatch: Start the internal mixer, set the speed to 45-55 rpm, add rubber, filler A, activator, antioxidant, tearing resin and microcrystalline wax, mix for 30-50 seconds, then mix for 20-30 seconds with the stopper lifted and pressed, and then mix until 150-165℃ to discharge the glue to obtain masterbatch 1. 2) Second stage masterbatch: Start the internal mixer, set the speed to 25-35 rpm, add masterbatch 1 and nano-reinforced composite material, mix for 30-50 seconds, then mix for 20-30 seconds with the plug lifted and pressed, and then mix until 135-145℃ to discharge the glue to obtain masterbatch 2. 3) Vulcanization: Start the internal mixer, set the speed to 25-35 rpm, add masterbatch 2, vulcanizing agent and anti-scorching agent CTP, mix for 30-50 seconds, then mix for 20-30 seconds with the plunger lifted and pressed, and finally mix until 105-115℃ to discharge the rubber, thus obtaining a low heat generation and high temperature resistant rubber composition.

[0019] Furthermore, the present invention also discloses a low-heat-generating, high-temperature-resistant tire, the base rubber of which is prepared by vulcanization of the aforementioned rubber composition.

[0020] The beneficial effects of this invention are as follows: Through the heterogeneous distribution of fillers, the nano-reinforced composite material can absorb a large amount of energy during the stretching process, thereby improving the resistance to damage and its high-temperature performance; the dihydrazide compound enhances the chemical bond between the nano-reinforced composite material and natural rubber, and reacts with the aldehyde, carboxyl and carbonyl groups at the rubber end, reducing the free radical end activity, thereby reducing heat generation. Detailed Implementation

[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present invention.

[0022] I. Terminology and Parameter Description 1. Rubber A: refers to the main phase rubber of the base rubber, which is selected from natural rubber (NR) and / or synthetic isoprene rubber (IR). The amount of rubber A in the composition of this invention is 65 to 80 parts by weight (based on a total of 100 parts by weight of rubber A + rubber B).

[0023] 2. Rubber B: Refers to the rubber phase used in the preparation of nano-reinforced composite materials, and natural rubber (NR) is selected. The total weight of Rubber B and Rubber A is 100 parts.

[0024] 3. Filler A: refers to the reinforcing filler of the main phase of the base adhesive, which is selected from carbon black and / or silica; the carbon black can be one or two of N375, N330, N339, N347 and N326.

[0025] 4. Filler B: refers to the nano / ultrafine reinforcing filler used in nano-reinforced composite materials, selected from one or more of carbon nanotubes, graphene, and nano carbon black; among which graphene can be 2 to 10 layers of graphene oxide, and carbon nanotubes can be arrayed multi-walled carbon nanotubes.

[0026] 5. Organosilicon polysulfides: These are compounds with silane end groups and polysulfide bond structures that can achieve filler-rubber interface coupling / crosslinking enhancement. They can be selected from one or more of the following: γ-mercaptopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, bis(3-mercaptopropyl)tetrasulfide, bis(3-mercaptopropyl)disulfide, mercaptoethyltriethoxysilane, mercaptopropylsiloxane copolymer, methylthiol silane, dimercaptoethylsilane, tetra(mercaptopropyl)silane, and bis(γ-triethoxysilylpropyl)sulfide.

[0027] 6. Diacylhydrazide compounds: These are compounds with the —CONHNHCO— structure, such as sebacic acid diacylhydrazide, which are used to react with aldehyde, carboxyl, carbonyl, and other groups produced at the ends or during oxidation of natural rubber. They enhance interfacial bonding and inhibit free radical end activity, thereby reducing hysteresis loss and heat generation.

[0028] 7. Low heat generation characterization index: In this embodiment, dynamic mechanical properties are used as the key indicator. (Loss factor at 60℃) and energy storage modulus at 60℃ As a typical evaluation indicator; The lower the value, the smaller the hysteresis loss and the lower the heat generation.

[0029] 8. Heterogeneous distribution of fillers / heterogeneous reinforcement structure: This refers to the two-stage blending of "nano-reinforced composite material (pre-dispersed masterbatch) + main phase masterbatch", which allows nano-fillers and some carbon black to preferentially accumulate in the composite material phase and disperse in the main phase masterbatch in the form of micro-regions, forming a multi-scale reinforcement structure of "hard phase micro-regions - soft phase continuous phase". Under high temperature dynamic deformation conditions, this improves the modulus and reduces the deformation amplitude, thereby reducing hysteresis loss.

[0030] 2. Raw materials Unless otherwise specified, the raw materials used in this embodiment can be selected from the following conventional sources, and are all commercially available products: Natural rubber (NR): Thai No. 20 or equivalent; Synthetic isoprene rubber (IR): Conventional tire-grade IR; Carbon black: N330, N375, and other tire-grade carbon black; Silica: Precipitated silica (e.g., 175GR grade or equivalent specific surface area grade); Zinc oxide (ZnO), stearic acid (SA), zinc stearate (ZnSt): Industrial grade; Antioxidants: Antioxidant 4020, Antioxidant RD (TMQ), etc.; Anti-scorching agent: CTP; Vulcanization system: sulfur + accelerator CZ / NS, etc., or alternatively dicumyl peroxide, etc.; Tear-resistant resin: CSR200 (polycyclopentadiene resin) or C5 / C9 modified resin; Microcrystalline wax: Tire-grade microcrystalline wax; Carbon nanotubes / graphene / nano-carbon black: nanomaterials for tire reinforcement or conductivity; Organosilicon polysulfides: bis-[γ-(triethoxysilane)propyl]tetrasulfide, etc.

[0031] III. Preparation methods of nano-reinforced composite materials The following describes a repeatable process for preparing nano-reinforced composite materials. The equipment can be an internal mixer (e.g., any size from 1.5L to 270L), with "rotor speed, time, and discharge temperature" as the key control elements.

[0032] Step B1: Device Setup Start the internal mixer and set the rotor speed to 30-45 rpm; the top bolt pressure is set according to the equipment's standard settings (e.g., 0.4-0.7 MPa), and the initial chamber temperature is controlled at 40-70℃.

[0033] Step B2: Feeding and Premixing After adding rubber B (natural rubber) and plasticizing for 10-20 seconds, add filler B and organosilicon polysulfides; mix for 25-40 seconds to allow the nanofiller to be initially wetted and dispersed in rubber B, while simultaneously enriching the organosilicon polysulfides at the interface.

[0034] Step B3: Add dihydrazide and complete the reactive dispersion. Add the dihydrazide compound and continue mixing for 1.0–2.5 minutes. During the mixing process, the discharge temperature is generally controlled at 110–140℃ (which can be adjusted according to the formula and equipment) to balance dispersion and avoid premature scorching.

[0035] Step B4: Degreasing and Parking After debinding, the material is passed through a two-roll mill 2-3 times to form a sheet. It is then left to stand at room temperature for ≥4 hours (or in accordance with the company's conventional rebound / stress release system) to obtain a nano-reinforced composite material (also known as "nano-reinforced masterbatch" or "nano-reinforced pre-dispersed adhesive").

[0036] By following the above-mentioned route of "first constructing nano-reinforced composite materials, and then combining them with the main phase masterbatch in a two-stage process", the effective dispersion and interfacial coupling efficiency of nanofillers can be significantly improved, enabling them to form a more stable multi-scale reinforcing micro-region structure in the final composition.

[0037] IV. Mixing Method of Low-Heat-Growth, High-Temperature-Resistant Base Rubber Composition The composition of this invention can be produced using a three-stage mixing process (two stages of masterbatch and final vulcanization). The following process parameters are illustrative and can be conventionally modified based on factors such as the internal mixer volume, top jack pressure, and cooling conditions.

[0038] (a) First stage of masterbatch (masterbatch 1) Start the internal mixer and set the rotor speed to 45-55 rpm. Add rubber A, filler A, activator (such as ZnO, stearic acid / zinc stearate), antioxidant, tear-resistant resin, and microcrystalline wax sequentially. Mix for 30-50 seconds, then perform a single-stage remixing for 20-30 seconds to improve filler wetting and dispersion. Continue remixing until the discharge temperature reaches 150-165℃ to obtain masterbatch 1. After discharge, the masterbatch can be thin-passed, sheeted, and cooled on an open mill to stabilize the temperature and stress of the rubber compound.

[0039] (ii) Second stage masterbatch (masterbatch 2) Start the internal mixer and set the rotor speed to 25-35 rpm; add masterbatch 1 and nano-reinforced composite material; mix for 30-50 seconds, then mix for 20-30 seconds with the plug lifted and pressed; continue mixing until the discharge temperature is 135-145℃ to discharge the masterbatch 2.

[0040] The purpose of this section is to achieve a uniform macroscopic distribution of nano-reinforced composite materials and main phase masterbatch without significantly damaging the nano-reinforced micro-region structure, thereby forming a heterogeneous reinforcing structure.

[0041] (III) Final Vulcanization (Finished Rubber) Start the internal mixer and set the rotor speed to 25–35 rpm; add masterbatch 2, vulcanizing agent (such as sulfur and accelerator system / or peroxide system), and scorch inhibitor CTP; mix for 30–50 seconds, then mix for 20–30 seconds with the plug lifted and pressed; control the discharge temperature at 105–115℃ to discharge the rubber, obtaining a low-heat-generating, high-temperature-resistant base rubber composition. The discharge temperature is controlled relatively low to reduce the risk of early vulcanization and processing scorch, and to ensure the effectiveness of the vulcanization system.

[0042] V. Vulcanization and Tire Preparation Vulcanization conditions can be determined using either a rotorless vulcanizer or a rotor vulcanizer. , The characteristic vulcanization time is determined, and the molding vulcanization or tire vulcanization regime is determined accordingly.

[0043] vulcanization of test pieces: conditions are 150–170℃, 10–20 minutes (within... (For reference only), the pressure is based on the mold and equipment specifications.

[0044] Tire application: The base rubber of this invention is used in the base rubber part of the tire structure (such as the base rubber layer between the tire carcass and the belt layer, the base rubber layer in the shoulder area, etc.), and is bonded and assembled according to conventional molding process. After being vulcanized by a tire vulcanizing machine, a low heat generation and high temperature resistant tire is obtained.

[0045] VI. Performance Testing Methods For ease of comparison, the following typical test methods are used in this embodiment; equivalent standards or enterprise standards may also be used in this field.

[0046] 1. Tensile properties at room temperature: Tested according to GB / T 528 or ISO 37 to obtain the stress at a constant elongation. , Tensile strength Elongation at break .

[0047] 2. High-temperature tensile properties (100℃): After preheating the specimen in a 100℃ constant temperature chamber for 20-30 minutes, the tensile test was conducted at 100℃ according to the above tensile method to obtain the tensile properties at 100℃. and .

[0048] 3. Dynamic Mechanical Properties (DMA): Take vulcanized samples and test them at a frequency of 10Hz (or a frequency similar to that of tire operating conditions) and a strain of 0.1-0.5% (within the linear viscoelastic region). Record the storage modulus at 60℃. and loss factor .

[0049] 4. Optional heat generation assessment: Evaluation methods include Goodrich flexural heat generation and RPA hysteresis loop area (this embodiment uses...). (Given by the main body).

[0050] VII. Examples and Comparative Examples (a) Formulation of nano-reinforced composite materials (Table A) Table A shows the formulations (parts by weight) of two representative nano-reinforced composite materials (A and B). A is a "carbon black-type nano-reinforced composite material," and B is a "carbon nanotube-synergistic nano-reinforced composite material," both conforming to the limitations of this invention.

[0051] Table A. Formulation of Nano-Reinforced Composite Materials (parts by weight)

[0052] Composite materials A and B were prepared according to the aforementioned steps B1 to B4: rotation speed 40 rpm; first add NR, filler B, and organosilicon polysulfide and mix for 30 seconds, then add dihydrazide and mix for 1.5 minutes to remove the glue.

[0053] (ii) Formulation of base adhesive composition (Table B) The following are 6 sets of example cases and 4 sets of comparative examples.

[0054] Note: Rubber A is the main phase rubber; the amount of nano-reinforced composite material is the amount of "pre-dispersed masterbatch" added to the second stage masterbatch; the rubber B contained therein has been included in the total rubber amount control of "rubber A + rubber B = 100 parts by weight" (for example, in Example 1, rubber A = 75, rubber B in nano-reinforced composite material A = 25, total rubber = 100).

[0055] Table B. Formulation of Low Heat Generation and High Temperature Resistant Base Adhesive Composition (parts by weight)

[0056] Comparative Example 1: Instead of using "nano-reinforced composite material preform masterbatch", organosilicon polysulfides were directly added during the two-stage mixing process (no nanofiller enriched micro-region structure).

[0057] Comparative Example 2: Similarly, no pre-made masterbatch was used. Only a small amount of nanofiller (CNT) and some carbon black were added in the second stage, resulting in insufficient dispersion and interfacial coupling.

[0058] Comparative Example 3: The formulation is similar to that of Comparative Example 2, but without the addition of dihydrazide compound, to illustrate the contribution of dihydrazide to maintaining high temperature modulus and low heat generation.

[0059] Comparative Example 4: The formulation is similar to that of Comparative Example 2, but without the addition of organosilicon polysulfides, to illustrate the contribution of coupling / interface enhancement to the overall performance.

[0060] (III) Mixing and vulcanization process The following process routes were used in all embodiments and comparative examples: First stage masterbatch: 50 rpm, mix for 40 seconds after feeding, lift and press the plug for 25 seconds, and discharge the glue at 160℃; Second stage masterbatch: 30 rpm, mix for 35 seconds, lift and press the plug for 20 seconds, and discharge the glue at 140℃; Final Vulcanization: 25 rpm, mix for 35 seconds, lift and press the plug for 30 seconds, and discharge the adhesive at 112℃.

[0061] Vulcanization conditions are based on the vulcanizing apparatus. Confirmed. Example: 160℃ × 15 minutes.

[0062] VIII. Performance Test Results and Analysis Table C Performance Test Results

[0063] Results Explanation: 1. Examples 1 and 2 compared to Comparative Examples 1 and 2: After using "nano-reinforced composite material (pre-made masterbatch)", at 100°C and Both significantly improved, indicating enhanced high-temperature modulus and strength retention; at the same time A decrease indicates a reduction in hysteresis loss and a decrease in heat generation.

[0064] 2. Comparative Example 3 (without dihydrazide): Compared to Comparative Example 2, in the presence of nanofillers, the lack of dihydrazide enhances interfacial chemistry and inhibits free radical termination, resulting in higher temperatures. and Decline and The increase indicates that dihydrazide makes a significant synergistic contribution to "high temperature resistance and low heat generation".

[0065] 3. Comparative Example 4 (without organosilicon polysulfides) compared to Comparative Example 2: Lacking coupling / interface reinforcement, the nanofiller is more prone to aggregation and interfacial slippage, leading to... The further increase in temperature modulus and the decrease in high-temperature modulus indicate that organosilicon polysulfides play a key role in constructing a stable reinforcing network and reducing hysteresis loss.

[0066] 4. Examples 3-6: Within the scope defined by this invention, adjusting the composition of rubber A (NR / IR), the proportion of filler A, and the amount of nano-reinforced composite material can maintain the basic trend of "increased high-temperature modulus and reduced hysteresis loss at 60℃", proving that the technical solution of this invention is feasible and has stable effects within the scope of this invention.

[0067] IX. Tire Implementation Examples The low-heat-generating, high-temperature-resistant base rubber composition obtained in Example 2 was selected as the tire base rubber and applied to the base rubber layer of an all-steel radial truck tire. During the tire molding process, the base rubber sheet was laid in the conventional bonding position, assembled with the tire carcass, belt layer, and other components, and then vulcanized according to the tire vulcanization regime. Compared with the control tire using the base rubber of Comparative Example 1, the tire of the present invention exhibits better modulus retention and lower temperature rise in the shoulder area under high-temperature conditions, reducing the risk of shoulder damage caused by heat accumulation, thereby improving tire durability and service life.

[0068] The foregoing description of embodiments of the present invention, through which those skilled in the art are able to implement or use the present invention, will be readily apparent to those skilled in the art. Various modifications to these embodiments will be readily apparent to those skilled in the art. The general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novelty disclosed herein.

Claims

1. A low-heat-generating, high-temperature-resistant base rubber composition, characterized in that, The rubber composition is prepared by mixing raw materials comprising the following components in parts by weight: Rubber A 65-80 parts, Packing material A: 30-55 parts Activator 3.5-8.5 parts, 2.0-5.0 parts of vulcanizing agent, Anti-aging agent 1.5-4.0 parts, 20-45 parts of nano-reinforced composite material The rubber A is natural rubber and / or synthetic isoprene rubber, and the filler A is carbon black and / or silica. The nano-reinforced wear-resistant composite material is prepared by mixing raw materials comprising the following components in parts by weight: Rubber B 20-40 parts, Packing material B: 1.0-10 parts 1-4 parts of organosilicon polysulfides 0.4-2 parts of diacylhydrazide compound; Rubber B is made of natural rubber; the total weight of rubber A and rubber B is 100 parts by weight, and the filler B is one or more of carbon nanotubes, graphene, and nano carbon black.

2. The rubber composition according to claim 1, characterized in that, The rubber composition is prepared by mixing raw materials comprising the following components in parts by weight: Rubber A 70-78 parts, Packing material A, 35-45 parts. Activator 4.0-6.5 parts, 2.5-3.5 parts of vulcanizing agent, Anti-aging agent 2.0-3.5 parts, 25-40 parts of nano-reinforced composite material The nano-reinforced wear-resistant composite material is prepared by mixing raw materials comprising the following components in parts by weight: Rubber B 20-35 parts, Packing material B: 2.0-5.0 parts. 1-2.5 parts of organosilicon polysulfides 0.5-1.5 parts of dihydrazide compound.

3. The rubber composition according to claim 1 or 2, characterized in that, The carbon black in filler A is one or two of N375, N330, N339, N347, and N326; And / or, the carbon nanotubes in filler B are arrayed, the carbon black is N375, N330, N339, N347 or N326, and the graphene is 2-10 layers of graphene oxide.

4. The rubber composition according to claim 1 or 2, characterized in that, The organosilicon polysulfide is selected from one or more of γ-mercaptopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, bis(3-mercaptopropyl)tetrasulfide, bis(3-mercaptopropyl)disulfide, mercaptoethyltriethoxysilane, mercaptopropylsiloxane copolymer, methylthiol silane, dimercaptoethylsilane, tetra(mercaptopropyl)silane, and bis(γ-triethoxysilylpropyl)sulfide.

5. The rubber composition according to claim 1 or 2, characterized in that, The activator is selected from one or more of zinc oxide, stearic acid, and zinc stearate; And / or, the antioxidant is selected from one or more of antioxidant 4010, antioxidant 4020, antioxidant RD, 2-mercaptobenzothiazole, and antioxidant TMQ; And / or, the vulcanizing agent is selected from one or more of sulfur, dicumyl peroxide, vulcanization accelerator NS, vulcanization accelerator CZ, and tetramethylthiuram disulfide.

6. The rubber composition according to claim 1 or 2, characterized in that, The raw materials for this rubber composition also include 0.5-1.5 parts of tear-resistant resin, 0.5-2 parts of microcrystalline wax, and 0.01-0.3 parts of scorch inhibitor CTP.

7. The rubber composition according to claim 6, characterized in that, The tear-resistant resin is one or more of polycyclopentadiene resin, C5 modified resin, and C9 modified resin.

8. The rubber composition according to claim 1 or 2, characterized in that, The preparation method of the nano-reinforced wear-resistant composite material includes the following steps: start the internal mixer, set the speed to 30-45 rpm, add natural rubber, filler and organosilicon polysulfide, mix for 25-40 seconds, add dihydrazide compound, continue mixing for 1-2.5 minutes, discharge the glue, and obtain the nano-reinforced composite material.

9. A method for mixing the rubber composition according to any one of claims 1-8, characterized in that, Includes the following steps: 1) First stage masterbatch: Start the internal mixer, set the speed to 45-55 rpm, add rubber, filler A, activator, antioxidant, tearing resin and microcrystalline wax, mix for 30-50 seconds, then mix for 20-30 seconds with the stopper lifted and pressed, and then mix until 150-165℃ to discharge the glue to obtain masterbatch 1. 2) Second stage masterbatch: Start the internal mixer, set the speed to 25-35 rpm, add masterbatch 1 and nano-reinforced composite material, mix for 30-50 seconds, then mix for 20-30 seconds with the plug lifted and pressed, and then mix until 135-145℃ to discharge the glue to obtain masterbatch 2. 3) Vulcanization: Start the internal mixer, set the speed to 25-35 rpm, add masterbatch 2, vulcanizing agent and anti-scorching agent CTP, mix for 30-50 seconds, then mix for 20-30 seconds with the plunger lifted and pressed, and finally mix until 105-115℃ to discharge the rubber, thus obtaining a low heat generation and high temperature resistant rubber composition.

10. A low-heat-generating, high-temperature-resistant tire, characterized in that, The base rubber of the tire is prepared by vulcanization of the rubber composition according to any one of claims 1-8.

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