Sizing material composition and preparation method and application of rubber compound of sizing material composition

Abstract

The invention belongs to the technical field of high polymer materials, and particularly relates to a sizing material composition and a preparation method and application of a rubber compound of the sizing material composition. The rubber composition provided by the invention is prepared from 90 to 110 parts of raw rubber, 3 to 5 parts of an adhesive AS-883, 5 to 8 parts of zinc oxide, 1 to 3 parts of stearic acid, 2 to 5.5 parts of an anti-aging agent, 25 to 35 parts of modified N330 carbon black, 10 to 15 parts of white carbon black, 1.5 to 3.5 parts of aromatic oil, 1.5 to 2.5 parts of a silane coupling agent, 2 to 4 parts of an anti-fatigue agent PL-600, 2 to 3 parts of insoluble sulfur and 2.5 to 5.5 parts of an accelerant. The rubber composition disclosed by the invention has high bonding strength with a composite cord thread and high bonding retention rate after aging, and also has the performance characteristics of high rebound value, good aging resistance and fatigue resistance, high tearing strength and tensile strength and low heat generation. The rubber composition disclosed by the invention is used as the tire body layer hanging rubber of the meridian aircraft tire, and the tire is safer to use.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, specifically relating to a rubber composition and its preparation method and application. Background Art

[0002] Radial aircraft tires are key components of aircraft takeoff and landing systems. The carcass layers of radial aircraft tires must withstand high loads and high-speed impacts during takeoff and landing, with the carcass cords, as the skeleton material, bearing the main mechanical load. Traditional aircraft tire carcass cords are mostly made of single-layer aramid or nylon, which suffers from insufficient impact resistance, poor fatigue resistance, and a tendency to delamination, making it difficult to meet the requirements of high-performance aircraft tires. Using aramid / nylon composite cords for the carcass layers of radial aircraft tires can combine the performance advantages of various materials, improving overall performance such as strength, modulus, and heat resistance. However, it also presents the problem of insufficient interfacial bonding between the composite cords and the carcass rubber coating.

[0003] Furthermore, the carcass ply of radial aircraft tires must withstand high loads and high-speed impacts during aircraft takeoff and landing. To ensure the carcass ply can adapt to the deformation and impact when the tire contacts the ground during use, the carcass ply rubber must also have high resilience, high tensile strength, and good adhesion to prevent carcass ply breakage or carcass ply separation due to stress concentration at the interface between the cords and the rubber compound, which could lead to sidewall bulges or tire blowouts. During frequent takeoffs, landings, and taxiing, the tire temperature can reach very high levels. Therefore, the rubber compound must have good heat resistance and thermal stability to prevent softening, deformation, or performance degradation due to overheating. Because aircraft tires operate in extremely harsh environments, to ensure performance under extreme conditions, the rubber compound must also have good aging resistance and fatigue resistance to prevent cracks and tears during long-term use. Summary of the Invention

[0004] The purpose of this invention is to provide a rubber compound composition, its preparation method, and its application. The rubber compound composition provided by this invention exhibits high adhesion strength to composite cords and high adhesion retention after aging. It also possesses high resilience, good aging and fatigue resistance, high tear and tensile strength, and low heat generation. When used as a coating for the carcass layer of radial aircraft tires, the rubber compound composition provides excellent impact resistance under high-speed and high-load conditions. It prevents localized breakage of the carcass cords or delamination between the carcass layer and adjacent layers, ensuring strong adhesion between the rubber compound and the cords and safe tire operation.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] This invention provides a rubber composition comprising the following raw materials in parts by weight:

[0007] Raw rubber 90-110 parts, adhesive AS-88 3-5 parts, zinc oxide 5-8 parts, stearic acid 1-3 parts, antioxidant 2-5.5 parts, modified N330 carbon black 25-35 parts, silica 10-15 parts, aromatic oil 1.5-3.5 parts, silane coupling agent 1.5-2.5 parts, anti-fatigue agent PL-600 2-4 parts, insoluble sulfur 2-3 parts, accelerator 2.5-5.5 parts;

[0008] The raw rubber comprises a first rubber and a second rubber, wherein the first rubber comprises polyisoprene rubber and / or natural rubber, and the second rubber is a polystyrene-butadiene copolymer rubber; the antioxidant comprises p-phenylenediamine antioxidant and ketone-amine antioxidant; the modified N330 carbon black has a loss on heating ≤0.3% and a 300% tensile stress of -0.5±1.2MPa; the accelerator comprises accelerator DZ and accelerator HV-268.

[0009] Preferably, in the rubber composition: the first rubber is 55-65 parts by mass, and the second rubber is 35-45 parts by mass.

[0010] Preferably, the antioxidant includes antioxidant S-RD and antioxidant 4020;

[0011] In the rubber composition: the antioxidant S-RD is present in 1 to 3 parts by mass, and the antioxidant 4020 is present in 1 to 2.5 parts by mass.

[0012] Preferably, in the rubber composition: the accelerator DZ is in the amount of 1.5 to 2.5 parts by mass, and the accelerator HV-268 is in the amount of 1 to 3 parts by mass.

[0013] Preferably, the modified N330 carbon black has an iodine absorption value of 82±6 mg / g and an oil absorption value of 97×10. -5 ~107×10 - 5 m 3 / kg, the oil absorption value of the compressed sample is 83×10 -5 ~93×10 -5 m 3 / kg, color strength 104±7%, CTAB adsorption specific surface area 73×10 3 ~85×10 3 m 2 / kg, with an external surface area of ​​700-800m² 2 / kg, total surface area is 73×10 3 ~83×10 3 m 2 / kg, pouring density is 380±40kg / m³ 2 Ash content ≤0.2%, residue on 45μm sieve ≤0.003%, total polycyclic aromatic hydrocarbon content ≤30ppm.

[0014] Preferably, the silane coupling agent is KH-560; the insoluble sulfur includes IS-60 and / or IS-90.

[0015] This invention provides a method for preparing the compound of the rubber composition described in the above technical solution, comprising the following steps:

[0016] The raw materials for preparing the rubber composition are mixed to obtain the compounded rubber of the rubber composition.

[0017] Preferably, the mixing includes direct mixing or segmented mixing; the segmented mixing includes the following steps:

[0018] Raw rubber, silica, silane coupling agent, zinc oxide, stearic acid, antioxidant, adhesive AS-88, modified N330 carbon black and aromatic oil are mixed in a first stage to obtain a first stage masterbatch. The rotation speed of the first stage mixing is 35-40 r / min.

[0019] The masterbatch, insoluble sulfur, accelerator, and anti-fatigue agent PL-600 are mixed in two stages to obtain the compound of the rubber composition. The rotation speed of the two-stage mixing is 25-30 r / min, and the two-stage mixing includes a bolt lifting operation, which is performed 2-3 times.

[0020] This invention provides the application of the rubber compound composition described in the above-described technical solution or the compound prepared by the preparation method described in the above-described technical solution in the application of rubber coating in tire carcass layers.

[0021] The present invention provides a rubber-coated tire cord fabric, comprising the rubber compound composition described in the above technical solution or the compound prepared by the preparation method described in the above technical solution; and the tire cord fabric.

[0022] This invention provides a rubber compound composition comprising the following raw materials in parts by weight: 90-110 parts raw rubber, 3-5 parts adhesive AS-88, 5-8 parts zinc oxide, 1-3 parts stearic acid, 2-5.5 parts antioxidant, 25-35 parts modified N330 carbon black, 10-15 parts silica, 1.5-3.5 parts aromatic oil, 1.5-2.5 parts silane coupling agent, 2-4 parts fatigue resistance agent PL-600, 2-3 parts insoluble sulfur, and an accelerator. 2.5–5.5 parts; the raw rubber comprises a first rubber and a second rubber, the first rubber comprising polyisoprene rubber and / or natural rubber, and the second rubber being a polystyrene-butadiene copolymer rubber; the antioxidant comprises p-phenylenediamine antioxidants and ketone-amine antioxidants; the modified N330 carbon black has a heating loss ≤0.3% and a 300% tensile stress of -0.5±1.2 MPa; the accelerator comprises accelerator DZ and accelerator HV-268. The rubber composition provided by this invention comprises a first rubber and a second rubber in the raw rubber. The first rubber has a simple molecular backbone structure and relatively small intermolecular forces, thus the first rubber molecules have good flexibility, providing good elasticity and processing properties for the rubber composition. However, the first rubber molecular backbone contains a large number of unsaturated double bonds, making it susceptible to the effects of oxygen, ozone, ultraviolet radiation, and thermal aging, leading to a decline in the performance of the rubber composition. This invention incorporates a second rubber compound. The polystyrene-butadiene copolymer rubber has a lower double bond content than the first rubber, making it more resistant to oxidation, ozone, and ultraviolet radiation. After reinforcement with modified N330 carbon black and silica, the tensile strength, abrasion resistance, and other mechanical properties of the polystyrene-butadiene copolymer rubber are significantly improved. This invention also includes adhesive AS-88, modified N330 carbon black, silica, silane coupling agent, accelerators DZ and HV-268, fatigue inhibitor PL-600, insoluble sulfur, p-phenylenediamine antioxidants, and ketone-amine antioxidants as auxiliary materials. The addition of adhesive AS-88 to the rubber compound improves the adhesion strength between the rubber compound and the composite cord, ensuring good adhesion even after aging. It also improves the plasticity of the compound, reduces heat generation, improves processing performance, and extends scorch time. Modified N330 carbon black and silica are used together as a reinforcing filler system. While maintaining the physical properties of the rubber compound, this significantly improves its tensile strength, abrasion resistance, tear strength, and reduces heat generation. Silica in the reinforcing filler system also acts as a bonding agent in the meta-methyl-silica system. The acidic silanol on the surface of silica improves the wettability of the rubber compound on the fiber surface and catalyzes the formation of meta-methyl adhesive resin. Simultaneously, due to the acidity of silica, the vulcanization reaction is delayed, allowing the rubber compound to maintain its fluidity for a longer period, synchronizing the vulcanization and bonding reactions, thus improving the adhesion between the rubber compound and the composite cord. This invention uses insoluble sulfur as the vulcanization system. Compared with ordinary sulfur, insoluble sulfur can overcome the disadvantage of poor adhesion caused by blooming during the storage period.The combined use of accelerators DZ and HV-268 increases the crosslinking density of the rubber compound during vulcanization, forming a stable crosslinking structure and improving the heat resistance and aging resistance of the rubber compound. Simultaneously, accelerator HV-268 exhibits a good synergistic effect with the silane coupling agent and antioxidant in the rubber compound, further enhancing the overall performance of the carcass layer. The antioxidant system of this invention uses a combination of p-phenylenediamine and ketone-amine antioxidants. P-phenylenediamine antioxidants possess excellent ozone resistance and flexural crack resistance, while ketone-amine antioxidants offer excellent protection against thermo-oxidative aging, delaying the aging process of rubber products under high temperature and oxygen conditions, thus extending their service life. Furthermore, ketone-amine antioxidants have good compatibility with rubber and are less prone to blooming. In this invention, the silane coupling agent can form a chemical bridge between the rubber and the cord, enhancing the interfacial bonding force, improving the adhesion between the rubber and the cord, reducing delamination between the rubber and the cord, improving the overall strength and durability of the tire carcass, and improving the stability of the tire under high load and high speed conditions. The fatigue-resistant agent PL-600 of this invention optimizes the arrangement of rubber molecular chains, resulting in more uniform stress distribution and thus reducing localized fatigue damage. Adding fatigue-resistant agent PL-600 to the rubber compound composition can reduce energy loss during repeated deformation of the rubber, reduce heat generation, and improve fatigue resistance. The active groups in fatigue-resistant agent PL-600 can react with functional groups on the surface of rubber molecules and cords to form stable chemical bonds, enhancing interfacial bonding force and improving peel resistance; therefore, it can also be used as a high-performance adhesive in rubber compounds. This invention optimizes the mass ratio of raw materials, enabling the rubber compound composition to have the best comprehensive performance. This ensures that the rubber compound composition has high bonding strength with the composite cord and high adhesion retention rate after aging. At the same time, it has the characteristics of high resilience, good aging and fatigue resistance, high tear strength and tensile strength, and low heat generation. Therefore, under high speed and high load conditions, it has good impact resistance and will not have problems such as delamination and bulging in the carcass layer, which would affect the tire's service life and safety. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the longitudinal section structure of the tire in this invention;

[0024] In the diagram: 1 is the tread rubber, 2 is the belt layer, 3 is the composite cord carcass layer, 4 is the airtight layer, and 5 is the bead wrapping rubber. Detailed Implementation

[0025] This invention provides a rubber composition comprising the following raw materials in parts by weight:

[0026] Raw rubber 90-110 parts, adhesive AS-88 3-5 parts, zinc oxide 5-8 parts, stearic acid 1-3 parts, antioxidant 2-5.5 parts, modified N330 carbon black 25-35 parts, silica 10-15 parts, aromatic oil 1.5-3.5 parts, silane coupling agent 1.5-2.5 parts, anti-fatigue agent PL-600 2-4 parts, insoluble sulfur 2-3 parts, accelerator 2.5-5.5 parts;

[0027] The raw rubber comprises a first rubber and a second rubber, wherein the first rubber comprises polyisoprene rubber and / or natural rubber, and the second rubber is a polystyrene-butadiene copolymer rubber; the antioxidant comprises p-phenylenediamine antioxidant and ketone-amine antioxidant; the modified N330 carbon black has a loss on heating ≤0.3% and a 300% tensile stress of -0.5±1.2MPa; the accelerator comprises accelerator DZ and accelerator HV-268.

[0028] In this invention, unless otherwise specified, all raw materials / components used in the preparation are commercially available products well known to those skilled in the art.

[0029] The rubber composition provided by this invention comprises 90-110 parts by weight of raw rubber, and in the examples, 100 parts. In this invention, the raw rubber comprises a first rubber and a second rubber. The first rubber comprises polyisoprene rubber and / or natural rubber, and in the examples, it can be either polyisoprene rubber or natural rubber. The second rubber is a polystyrene-butadiene copolymer rubber. The polystyrene-butadiene copolymer rubber has a higher upper limit temperature for use than natural rubber, and its price is also lower than that of natural rubber. In the rubber composition: the first rubber preferably comprises 55-65 parts by weight, and in the examples, it can be 55, 60, or 65 parts; the second rubber preferably comprises 35-45 parts by weight, and in the examples, it can be 45, 40, or 35 parts. This invention uses the first rubber as the main material, which can provide good elasticity and processing performance for the rubber composition; and the use of polystyrene-butadiene copolymer rubber can improve the wear resistance, fatigue resistance, and aging resistance of the rubber composition, and reduce production costs.

[0030] Based on the mass fraction of the raw rubber, the rubber composition provided by this invention includes 3 to 5 parts of adhesive AS-88, which may be 3, 4, or 5 parts in the embodiments. The adhesive AS-88 of this invention has dual functions as a methylene acceptor and methylene donor, and is a type of meta-methyl-white adhesive. It can be used as a single component, requiring a small amount, which helps reduce tire manufacturing costs. Adding it to the rubber composition can improve the bonding strength between the rubber and the composite cord, allowing the rubber to maintain good adhesion even after aging. It can also improve the plasticity of the compound, reduce heat generation, improve processing performance, and extend scorch time.

[0031] Based on the mass fraction of the raw rubber, the rubber composition provided by the present invention includes 5 to 8 parts of zinc oxide, which may be 5 parts, 6.5 parts, or 8 parts in the examples.

[0032] Based on the mass fraction of the raw rubber, the rubber composition provided by the present invention includes 1 to 3 parts of stearic acid, which may be 1 part, 2 parts or 3 parts in the examples.

[0033] Based on the mass fraction of the raw rubber, the rubber compound composition provided by the present invention includes 2 to 5.5 parts of antioxidant, which may be 4 parts or 3.5 parts in the examples. The antioxidant includes p-phenylenediamine antioxidants and ketone amine antioxidants. Preferably, the antioxidant includes antioxidant S-RD and antioxidant 4020. In the rubber compound composition: the mass fraction of antioxidant S-RD is preferably 1 to 3 parts, which may be 1 part, 2 parts, or 3 parts in the examples; the mass fraction of antioxidant 4020 is preferably 1 to 2.5 parts, which may be 1 part, 1.5 parts, or 2.5 parts in the examples.

[0034] Based on the mass fraction of the raw rubber, the rubber composition provided by this invention includes 25-35 parts of modified N330 carbon black, which can be 25 parts, 30 parts, or 35 parts in the examples. In this invention, the modified N330 carbon black preferably has a loss on heating of ≤0.3% and a 300% tensile stress preferably of -0.5±1.2 MPa; the modified N330 carbon black preferably has an iodine absorption value of 82±6 mg / g and an oil absorption value preferably of 97×10⁻⁶ mg / g. -5 ~107×10 -5 m 3 / kg, the preferred oil absorption value for compressed samples is 83×10⁻⁶. -5 ~93×10 -5 m 3 / kg, the preferred coloring strength is 104±7%, and the preferred CTAB adsorption specific surface area is 73×10⁻⁶. 3 ~85×10 3 m 2 / kg, with an external surface area preferably of 700-800m². 2 / kg, with a preferred total surface area of ​​73×10⁻⁶. 3 ~83×10 3 m 2 / kg, the preferred pouring density is 380±40kg / m³ 2 The ash content is preferably ≤0.2%, the residue on a 45μm sieve is preferably ≤0.003%, and the total content of 18 polycyclic aromatic hydrocarbons is preferably ≤30ppm. In the embodiments of the present invention, the modified N330 carbon black is manufactured by Xinjiang Junxin Chemical Co., Ltd.

[0035] Based on the mass fraction of the raw rubber, the rubber composition provided by the present invention includes 10 to 15 parts of silica, which may be 10 parts, 12.5 parts or 15 parts in the examples.

[0036] Carbon black possesses advantages such as high reinforcing properties, excellent electrical / thermal conductivity, and low production cost. However, high filler content of carbon black can easily lead to increased hardness, decreased elasticity, and increased heat generation in rubber compounds. Silica can improve the flexibility and aging resistance of rubber compounds and reduce rolling resistance, but silica has poor electrical conductivity, weaker reinforcing effect than carbon black, and higher cost when used alone. This invention uses modified N330 carbon black and silica in combination. By rationally adjusting the mass ratio of modified N330 carbon black to silica, the mechanical strength, elasticity, and processing performance of the rubber compound can be balanced. The modified N330 carbon black used in this invention exhibits better dispersibility in the rubber compound and is more stable at high temperatures, making it suitable for high-temperature environments.

[0037] Based on the mass fraction of the raw rubber, the rubber composition provided by the present invention includes 1.5 to 3.5 parts of aromatic oil, which may be 1.5 parts, 2.5 parts, or 3.5 parts in the embodiments.

[0038] Based on the mass fraction of the raw rubber, the rubber composition provided by the present invention includes 1.5 to 2.5 parts of silane coupling agent, which may be 1.5 parts, 2 parts, or 2.5 parts in the examples. In the present invention, the silane coupling agent is preferably KH-560.

[0039] Based on the mass fraction of the raw rubber, the rubber composition provided by the present invention includes 1 to 4 parts of anti-fatigue agent PL-6002, which may be 2, 3 or 4 parts in the examples.

[0040] Based on the mass fraction of the raw rubber, the rubber composition provided by the present invention includes 2 to 3 parts of insoluble sulfur, which may be 2 parts, 2.5 parts, or 3 parts in the examples. In the present invention, the insoluble sulfur preferably includes IS-60 and / or IS-90.

[0041] Based on the mass fraction of the raw rubber, the rubber compound composition provided by the present invention includes 2.5 to 5.5 parts of accelerator, which can be 4.5 parts, 4 parts, or 3.5 parts in the examples. In the present invention, the accelerator includes accelerator DZ and accelerator HV-268. In the rubber compound composition: the mass fraction of accelerator DZ is preferably 1.5 to 2.5 parts, which can be 1.5 parts, 2 parts, or 2.5 parts in the examples; the mass fraction of accelerator HV-268 is preferably 1 to 3 parts, which can be 1 part, 2 parts, or 3 parts in the examples.

[0042] This invention provides a method for preparing the compound of the rubber composition described in the above technical solution, comprising the following steps:

[0043] The raw materials for preparing the rubber composition are mixed to obtain the compounded rubber of the rubber composition.

[0044] In this invention, the mixing preferably includes direct mixing or staged mixing. Direct mixing is suitable for small-scale compounding experiments. Direct mixing is preferably carried out in an internal mixer. The preferred model of the internal mixer used for direct mixing is X(S)M1.7L. The direct mixing preferably includes: pre-mixing the raw rubber, then adding silica and a silane coupling agent and continuing mixing, then adding zinc oxide, stearic acid, an antioxidant, and adhesive AS-88 and continuing mixing, then adding modified N330 carbon black and continuing mixing, then adding aromatic oil and continuing mixing, and finally adding insoluble sulfur, an accelerator, and an anti-fatigue agent PL-600 and continuing mixing. This invention does not have special requirements regarding the timing of the pre-mixing and subsequent mixing in the direct mixing process.

[0045] In this invention, the staged mixing preferably includes the following steps: a staged mixing of raw rubber, silica, silane coupling agent, zinc oxide, stearic acid, antioxidant, binder AS-88, modified N330 carbon black, and aromatic oil to obtain a staged masterbatch; and a second staged mixing of the staged masterbatch, insoluble sulfur, accelerator, and fatigue inhibitor PL-600 to obtain the compounded rubber of the rubber composition. In this invention, the staged mixing is suitable for bulk production in a workshop. The staged mixing is preferably carried out in an internal mixer, preferably a GK250E model. The rotation speed of the staged mixing is preferably 35-40 r / min. The staged mixing preferably includes: pre-mixing the raw rubber, then adding silica and silane coupling agent and continuing mixing, then adding zinc oxide, stearic acid, antioxidant, and binder AS-88 and continuing mixing, then adding modified N330 carbon black and continuing mixing, then adding aromatic oil and continuing mixing, and finally discharging the rubber to obtain a staged masterbatch. The preferred rotation speed for the two-stage mixing is 25–30 r / min. The two-stage mixing preferably includes: continuing to mix the first-stage compound, then adding insoluble sulfur, an accelerator, and the fatigue inhibitor PL-600 and continuing mixing, followed by a bolt-lifting operation, preferably 2–3 times, and finally discharging the compound to obtain the final rubber composition. This invention does not impose special requirements on the pre-mixing and subsequent mixing times during the segmented mixing process.

[0046] This invention provides the application of the rubber compound composition described in the above-described technical solution or the rubber compound prepared by the preparation method described in the above-described technical solution in the application of rubber coating in tire carcass layers.

[0047] The present invention provides a rubber-coated tire cord fabric, comprising the rubber compound composition described in the above technical solution or the compound prepared by the preparation method described in the above technical solution; and the tire cord fabric.

[0048] This invention optimizes the mass ratio of raw materials in the preparation of the rubber composition, thereby ensuring that the rubber composition has high bonding strength with the composite cord and high adhesion retention rate after aging, while also having high resilience, good aging and fatigue resistance, high tear strength and tensile strength, and low heat generation.

[0049] To further illustrate the present invention, the technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0050] Examples 1-3:

[0051] Examples 1-3 provide a rubber composition. The raw materials for preparing the rubber composition and the mass fraction of each raw material are shown in Table 1. In Examples 1 and 2, polyisoprene rubber was used, and in Example 3, natural rubber was used. In Examples 1 and 2, insoluble sulfur IS-60 was used, and in Example 3, insoluble sulfur IS-90 was used.

[0052] Table 1. Types and mass fractions of raw materials for the rubber compositions provided in Examples 1-3

[0053] Raw material name Example 1 Example 2 Example 3 Polyisoprene rubber / natural rubber 55 60 65 Polystyrene-butadiene copolymer rubber 45 40 35 Adhesive AS-88 3 4 5 ZnO 5 6.5 8 stearic acid 1 2 3 Anti-aging agent S-RD 3 2 1 Anti-aging agent 4020 1 1.5 2.5 Modified N330 carbon black 25 30 35 Silica 15 12.5 10 Aromatic oils 1.5 2.5 3.5 Silane coupling agent KH-560 1.5 2 2.5 Anti-fatigue agent PL-600 4 3 2 Insoluble sulfur IS-60 / IS-90 2 2.5 3 Accelerator DZ 1.5 2 2.5 Accelerator HV-268 3 2 1

[0054] The specific methods for preparing the compound rubber of the rubber compositions provided in Examples 1-3 are as follows:

[0055] The small-scale compound test rubber was mixed on an X(S)M1.7L internal mixer with a rotor speed of 40 rpm. The feeding sequence was as follows: raw rubber (polyisoprene rubber / natural rubber, polystyrene-butadiene copolymer rubber) → silica, silane coupling agent KH-560 → zinc oxide, stearic acid, antioxidant S-RD, antioxidant 4020, adhesive AS-88 → modified N330 carbon black → aromatic oil → insoluble sulfur IS-60 / IS-90, accelerator DZ, accelerator HV-268, fatigue inhibitor PL-600.

[0056] The bulk materials in the workshop are mixed in two stages, both within a GK250E internal mixer:

[0057] The rotor speed of the first mixing stage is 35 r / min. The feeding sequence is: raw rubber → silica, silane coupling agent KH-560 → zinc oxide, stearic acid, antioxidant S-RD, antioxidant 4020, adhesive AS-88 → modified N330 carbon black → aromatic oil → discharge.

[0058] The rotor speed for the two-stage mixing process is 30 r / min. The feeding sequence is as follows: first-stage masterbatch → insoluble sulfur IS-60, accelerator DZ, accelerator HV-268, fatigue resistant agent PL-600 → lifting the plug 2-3 times → discharging the rubber.

[0059] The properties of the rubber compounds prepared from the rubber compositions provided in Examples 1-3 are shown in Table 2. The vulcanization conditions of the rubber compounds in Table 2 are: 138℃ × 55 min, vulcanization pressure: 12.0 MPa.

[0060] Table 2 shows the properties of the compounded rubber prepared from the rubber compositions provided in Examples 1-3.

[0061] project Example 1 Example 2 Example 3 <![CDATA[138℃ Mooney viscometer t 10 / min]]> 18.32 16.51 15.66 <![CDATA[138℃ Mooney viscometer t 90 / min]]> 54.56 51.83 48.54 120℃ scorching time (min) 52.43 49.20 46.31 Shore A hardness 55 57 58 300% constant tensile stress (MPa) 10.9 11.3 12.1 Tensile strength (MPa) 30 28 25 Elongation at break % 570 535 490 Permanent deformation after tearing 26 22 20 Elongation (%) after aging at 100℃ for 24 hours -21.5 -22 -23 Tear strength (right angle) kN / m 97 93 90 Rebound value % 56 52 43 Heat generation ℃ / 25min 18 21 25 H extraction value N / 10mm 250 235 220 H extraction value N / 10mm after aging at 100℃ for 24 hours 250 235 220

[0062] Table 2 shows that the compound prepared using the rubber composition formulations of Examples 1-3 exhibits high bonding strength with the composite cord and high adhesion retention after aging. All other properties meet the requirements of the radial aircraft tire carcass layer. The compound obtained by internal mixing is pressure-applied on a calender, attaching it to the upper and lower surfaces of the composite cord fabric, allowing some rubber to penetrate into the cord gaps, thus creating a rubber-coated cord fabric. This fabric is then cut, bonded, and shaped layer by layer to form a tire carcass. The carcass is then vulcanized in a vulcanizing machine to become the finished radial aircraft tire. The location of the rubber coating in the composite cord carcass layer of this invention is shown in the figure. Figure 1 .

[0063] Comparative Examples 1-5:

[0064] Comparative Examples 1-5 provide a rubber compound composition. The raw materials for preparing the rubber compound composition and the mass fraction of each raw material are shown in Table 3. Among them, Comparative Examples 1, 2, 3, 4, and 5 use natural rubber. Comparative Examples 1, 2, and 5 use insoluble sulfur IS-60, while Comparative Examples 3 and 4 use insoluble sulfur IS-90.

[0065] Table 3 shows the types and parts by weight of raw materials in the rubber compositions provided in Comparative Examples 1-5.

[0066]

[0067]

[0068] The specific methods for preparing the compound rubber of the rubber compositions provided in Comparative Examples 1 to 5 are as follows:

[0069] The small-scale compound test rubber was mixed on an X(S)M1.7L internal mixer with a rotor speed of 40 rpm. The feeding sequence was as follows: raw rubber (polyisoprene rubber / natural rubber, polystyrene-butadiene copolymer rubber) → silica, silane coupling agent KH-560 → zinc oxide, stearic acid, antioxidant S-RD, antioxidant 4020, adhesives (adhesive AS-88, resorcinol-80, adhesive RS, adhesive RA) → carbon black (modified N330 carbon black / N236 carbon black) → aromatic oil → insoluble sulfur IS-60 / IS-90, accelerator DZ, accelerator HV-268, fatigue inhibitor PL-600.

[0070] The properties of the rubber compounds prepared from the rubber compositions provided in Comparative Examples 1 to 5 are shown in Table 4. The vulcanization conditions of the rubber compounds in Table 4 are: 138℃ × 55 min, vulcanization pressure: 12.0 MPa.

[0071] Table 4 shows the properties of the compounded rubber prepared from the rubber compositions provided in Comparative Examples 1-5.

[0072]

[0073]

[0074] Table 4 shows that the carcass ply compound in Comparative Example 1, which uses only natural rubber as the main material, exhibits a significant decrease in elongation at break and a drop in adhesive strength from 237 N to 174 N after aging at 100℃ for 24 hours. This indicates that using only natural rubber as the main material results in poor aging resistance, leading to a decline in compound performance after aging and failing to meet the requirements for high-performance aviation tires. In Comparative Example 2, the adhesive RS used is a blend of resorcinol and stearic acid, belonging to the methylene acceptor adhesive category. Without a methylene donor, adhesive RS lacks adhesive ability and requires the use of adhesives such as adhesive RA to achieve bonding. Resorcinol in adhesive RS is highly toxic and expensive, difficult to disperse at low temperatures, and prone to sublimation and white fumes at high temperatures. Furthermore, it easily sprays out of the compound, reducing its physical and adhesive properties and hindering performance stability and process control. In Comparative Example 3, the formulation lacks silica as a reinforcing agent, resulting in lower tear strength and elasticity, higher heat generation, and poor adhesion due to the absence of silica as an adhesive enhancer in the meta-methyl-silica system. In Comparative Example 4, the vulcanization system uses only accelerator DZ, which is an ultra-fast accelerator, leading to a shorter scorch time and compromised processing safety. Comparative Example 5 differs from Comparative Example 2 in the amount of raw rubber and silica used, resulting in different physical properties of the rubber compound. The rubber compound obtained from the formulation of this invention exhibits superior physical properties compared to those of Comparative Examples 1-5, demonstrating the crucial role of raw materials and their proportions in improving compound performance.

[0075] Comparative Example 6:

[0076] Comparative Example 6 provides a rubber composition, and the raw materials for preparing the rubber composition and the mass fractions of each raw material are shown in Table 5.

[0077] Table 5 shows the types and parts by weight of raw materials in the rubber compositions provided in Comparative Example 6.

[0078]

[0079]

[0080] The specific method for preparing the compound of the rubber composition provided in Comparative Example 6 is as follows:

[0081] The small-scale compound test rubber was mixed on an X(S)M1.7L internal mixer with a rotor speed of 40 rpm. The feeding sequence was as follows: raw rubber (1# smoked sheet rubber, styrene-butadiene rubber) → silica → zinc oxide, stearic acid, antioxidant 4010NA, adhesive RS, adhesive RA → carbon black (high abrasion resistant carbon black N339, general-purpose carbon black N660) → aromatic oil → soluble sulfur IS-60, accelerator NOBS, accelerator TDTM, antioxidant 4010NA, heat stabilizer WK-901.

[0082] Comparative Example 7:

[0083] Comparative Example 7 provides a rubber composition, and the raw materials for preparing the rubber composition and the mass fractions of each raw material are shown in Table 6.

[0084] Table 6 shows the types and parts by weight of raw materials in the rubber compositions provided in Comparative Example 7.

[0085]

[0086] The specific method for preparing the compound of the rubber composition provided in Comparative Example 7 is as follows:

[0087] The small-scale test rubber compounds were mixed on an X(S)M1.7L internal mixer with a rotor speed of 40 rpm. The feeding sequence was: isoprene rubber → silica, silane coupling agent → zinc oxide, stearic acid, antioxidant BLE → N774 carbon black → aromatic oil → insoluble sulfur IS-60, accelerator NOBS, antioxidant 4020.

[0088] Comparative Example 8:

[0089] Comparative Example 8 provides a rubber composition, and the raw materials for preparing the rubber composition and the mass fractions of each raw material are shown in Table 7.

[0090] Table 7 shows the types and mass fractions of raw materials in the rubber composition provided in Comparative Example 8. (Failure Case 3)

[0091]

[0092] The specific method for preparing the compound of the rubber composition provided in Comparative Example 8 is as follows:

[0093] The small-scale compound test rubber was mixed on an X(S)M1.7L internal mixer with a rotor speed of 40 / min. The feeding sequence was as follows: raw rubber (styrene-butadiene rubber, cis-butadiene rubber) → silica, silane coupling agent → zinc oxide, stearic acid, antioxidant 4010 → N236 carbon black → aromatic oil → insoluble sulfur IS-6, accelerator TBBA, accelerator DGP.

[0094] The properties of the rubber compounds prepared from the rubber compositions provided in Comparative Examples 6-8 are shown in Table 8. The vulcanization conditions of the rubber compounds in Table 8 are: 138℃ × 55 min, vulcanization pressure: 12.0 MPa.

[0095] Table 8 shows the properties of the compounded rubber prepared from the rubber compositions provided in Comparative Examples 6-8.

[0096]

[0097]

[0098] As can be seen from the above embodiments, the present invention provides a rubber compound composition for using composite cords as the adhesive for the carcass ply of radial aircraft tires. The rubber compound composition provided by the present invention has high adhesion strength to the composite cords and high adhesion retention rate after aging. It also features high resilience, good aging and fatigue resistance, high tear strength and tensile strength, and low heat generation. When used as the adhesive for the carcass ply of radial aircraft tires, this rubber compound enables the tire to have good impact resistance under high-speed and high-load conditions. It prevents localized breakage of the carcass cords or delamination between the carcass ply and adjacent ply layers. The rubber compound adheres firmly to the cords, ensuring safe tire use. The performance of this rubber compound has been tested, and its performance range is shown in Table 9. The vulcanization conditions of the compound in Table 9 are: 138℃ × 55min, vulcanization pressure: 12.0MPa.

[0099] Table 9. Performance of the rubber composition provided by the present invention

[0100] project unit Performance range Tensile strength MPa 25～30 Elongation at break ％ 490～570 Elongation change rate after aging at 100℃ for 24 hours ％ -21.5～-23 Tear strength (right angle) kN / m 90～97 rebound value ％ 43～56 Compression fatigue heat generation ℃ / 25min 18～25 H-extraction value N / 10mm 220～250 H extraction value after aging at 100℃ for 24 hours N / 10mm 220～250

[0101] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. Other embodiments can be obtained based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A rubber composition, characterized in that, The preparation raw materials include the following parts by weight: Raw rubber 90-110 parts, adhesive AS-88 3-5 parts, zinc oxide 5-8 parts, stearic acid 1-3 parts, antioxidant 2-5.5 parts, modified N330 carbon black 25-35 parts, silica 10-15 parts, aromatic oil 1.5-3.5 parts, silane coupling agent 1.5-2.5 parts, anti-fatigue agent PL-600 2-4 parts, insoluble sulfur 2-3 parts, accelerator 2.5-5.5 parts; The raw rubber comprises a first rubber and a second rubber, wherein the first rubber comprises polyisoprene rubber and / or natural rubber, and the second rubber is a polystyrene-butadiene copolymer rubber; the antioxidant comprises p-phenylenediamine antioxidant and ketone-amine antioxidant; the modified N330 carbon black has a loss on heating ≤0.3% and a 300% tensile stress of -0.5±1.2MPa; the accelerator comprises accelerator DZ and accelerator HV-268.

2. The rubber composition according to claim 1, characterized in that, In the rubber composition: the first rubber is 55-65 parts by mass, and the second rubber is 35-45 parts by mass.

3. The rubber composition according to claim 1, characterized in that, The antioxidants include antioxidant S-RD and antioxidant 4020; In the rubber composition: the antioxidant S-RD is present in 1 to 3 parts by mass, and the antioxidant 4020 is present in 1 to 2.5 parts by mass.

4. The rubber composition according to claim 1, characterized in that, In the rubber composition: the accelerator DZ is in the amount of 1.5 to 2.5 parts by mass, and the accelerator HV-268 is in the amount of 1 to 3 parts by mass.

5. The rubber composition according to claim 1, characterized in that, The modified N330 carbon black has an iodine absorption value of 82±6 mg / g and an oil absorption value of 97×10⁻⁶ mg / g. -5 ~107×10 -5 m 3 / kg, the oil absorption value of the compressed sample is 83×10 -5 ~93×10 -5 m 3 / kg, color strength 104±7%, CTAB adsorption specific surface area 73×10 3 ~85×10 3 m 2 / kg, with an external surface area of ​​700-800m² 2 / kg, total surface area is 73×10 3 ~83×10 3 m 2 / kg, pouring density is 380±40kg / m³ 2 Ash content ≤0.2%, residue on 45μm sieve ≤0.003%, total polycyclic aromatic hydrocarbon content ≤30ppm.

6. The rubber composition according to claim 1, characterized in that, The silane coupling agent is KH-560; the insoluble sulfur includes IS-60 and / or IS-90.

7. A method for preparing the compound of the rubber composition according to any one of claims 1 to 6, characterized in that, The following steps are involved: The raw materials for preparing the rubber composition are mixed to obtain the compounded rubber of the rubber composition.

8. The preparation method according to claim 7, characterized in that, The mixing includes direct mixing or staged mixing; the staged mixing includes the following steps: Raw rubber, silica, silane coupling agent, zinc oxide, stearic acid, antioxidant, adhesive AS-88, modified N330 carbon black and aromatic oil are mixed in a first stage to obtain a first stage masterbatch. The rotation speed of the first stage mixing is 35-40 r / min. The masterbatch, insoluble sulfur, accelerator, and anti-fatigue agent PL-600 are mixed in two stages to obtain the compound of the rubber composition. The rotation speed of the two-stage mixing is 25-30 r / min, and the two-stage mixing includes a bolt lifting operation, which is performed 2-3 times.

9. The application of the rubber compound composition according to any one of claims 1 to 6 or the compound prepared by the preparation method according to any one of claims 7 to 8 in the application of rubber to the tire carcass layer.

10. A type of adhesive-coated curtain fabric, characterized in that, The compound includes the rubber composition according to any one of claims 1 to 6 or the rubber composition prepared by the preparation method according to claim 7 or 8; and tire cord fabric.

Images