Sizing material composition, preparation method thereof and application of sizing material composition as wave-shaped steel wire coating rubber of aviation radial tire

Abstract

The invention belongs to the technical field of rubber processing and aircraft tire manufacturing, and particularly relates to a rubber composition, a preparation method thereof and application of the rubber composition as wave-shaped steel wire coating rubber of an aircraft radial tire. The rubber composition provided by the invention is prepared from 100 parts of natural rubber, 78 to 100 parts of a reinforcing system, 1.2 to 1.5 parts of a silane coupling agent, 3.5 to 6 parts of a bonding system, 0.3 to 0.5 part of a bonding promoter, 3.5 to 5.3 parts of an aging protection system, 2 to 5.7 parts of a crosslinking system, 6 to 6.5 parts of a crosslinking activation system, 5 to 8 parts of a plasticizing system and 3 to 5 parts of tackifying resin. The rubber composition provided by the invention has the advantages of excellent heat resistance, low compression fatigue temperature rise, high tensile strength and high elongation at break, and can form good adhesion with a wavy steel wire, so that the service life of the aviation radial tire is remarkably prolonged, the safety performance of the aviation radial tire is remarkably improved, and the puncture resistance of the aviation radial tire is effectively enhanced.

Description

Technical Field

[0001] The invention belongs to the technical field of rubber processing and aviation tire manufacturing, and specifically relates to a rubber composition and a preparation method thereof and an application thereof as a corrugated steel wire coating rubber for aviation radial tires. Background Art

[0002] Aircraft tires are subjected to tremendous pressure and friction during takeoff and landing, and their performance is directly related to flight safety and operating efficiency. The belt layer protection layer is one of the key designs to improve the performance of aircraft radial tires. This protection layer is located between the belt layer and the tread rubber (see Figure 1 ) is designed to enhance the tire's resistance to punctures and cuts during takeoff and landing, thereby improving overall safety.

[0003] In the material selection of the belt layer protection layer, steel cord and aramid fiber cord are the two main skeleton materials, which need to be processed into wavy cords in the manufacturing process of aircraft tires. Although aramid fiber performs well in tensile strength and heat resistance, wavy steel wire (see Figure 2 ) has become the preferred material for the corrugated protective layer of aviation radial tires due to its superiority in strength, rigidity, wear resistance and impact resistance, as well as relatively low cost and good processing adaptability.

[0004] There are significant differences in design and process between the corrugated steel wire rubber and the traditional aircraft tire bead steel wire ring rubber. The design complexity of the corrugated steel wire rubber is reflected in its geometric shape and stress characteristics. The structure must not only ensure good adhesion to ensure that the external load is effectively transferred to the skeleton material through the rubber matrix, but also maintain sufficient flexibility and strength under various working conditions. The corrugated steel wire rubber must meet the following requirements: (1) High adhesion: The rubber must have excellent adhesion properties to ensure a firm bond between the corrugated steel wire and the rubber layer to prevent peeling and failure; (2) Excellent elasticity: The rubber should have good elasticity to adapt to the deformation requirements of the corrugated structure and ensure that stress can be effectively dispersed under stress; (3) High temperature resistance: Since aircraft tires work in high temperature environments, the rubber must have excellent high temperature resistance to prevent performance degradation under extreme conditions; (4) Processing adaptability: The rubber should have good processing adaptability to adapt to complex coating processes and vulcanization processes to ensure production efficiency and product consistency.

[0005] However, the rubber compounds currently available on the market cannot meet the requirements of corrugated steel wire coating, which limits the improvement of the overall performance of aviation tires. Summary of the invention

[0006] The purpose of the present invention is to provide a rubber composition and a preparation method thereof and an application thereof as a rubber coating for corrugated steel wires of aviation radial tires. The rubber composition provided by the present invention has excellent heat resistance, low compression fatigue temperature rise, high tensile strength and high elongation at break, and still maintains good adhesion performance after aging. As a rubber coating for corrugated steel wires of aviation radial tires, it can form good adhesion with the corrugated steel wires, significantly improve the service life and safety performance of aviation radial tires, and effectively enhance the puncture resistance of aviation radial tires.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] The present invention provides a sizing composition, comprising the following raw materials in parts by weight:

[0009] 100 parts of natural rubber, 78-100 parts of reinforcement system, 1.2-1.5 parts of silane coupling agent, 3.5-6 parts of bonding system, 0.3-0.5 parts of adhesion promoter, 3.5-5.3 parts of aging protection system, 2-5.7 parts of cross-linking system, 6-6.5 parts of cross-linking activation system, 5-8 parts of plasticizing system, 3-5 parts of tackifying resin;

[0010] The reinforcement system includes carbon black and white carbon black;

[0011] The bonding system includes a methylene donor and an adhesive RS;

[0012] The aging protection system includes p-phenylenediamine antioxidant and ketoamine antioxidant;

[0013] The cross-linking system includes insoluble sulfur, sulfenamide accelerator and scorch retarder;

[0014] The cross-linking activation system includes zinc oxide and stearic acid;

[0015] The plasticizing system includes an aromatic oil.

[0016] Preferably, the carbon black is carbon black N326, and the mass ratio of the carbon black to white carbon black is (70-90):(8-10).

[0017] Preferably, the methylene donor is HMMM-55, and the mass ratio of the methylene donor to the adhesive RS is (2-3): (1.5-3).

[0018] Preferably, the p-phenylenediamine antioxidant is p-phenylenediamine antioxidant 4020, and the ketoamine antioxidant is antioxidant BLE; the mass ratio of the p-phenylenediamine antioxidant to the ketoamine antioxidant is (2-3):(1.5-2.3).

[0019] Preferably, the insoluble sulfur is insoluble sulfur HDOT, the sulfonamide accelerator is sulfonamide accelerator DCBS-80, and the anti-scorch agent is anti-scorch agent CTP; the mass ratio of the insoluble sulfur, the sulfonamide accelerator and the anti-scorch agent is (2-4): (0.8-1.5): 0.2.

[0020] Preferably, the mass ratio of zinc oxide to stearic acid is 5:(1-1.5).

[0021] Preferably, the adhesion promoter is cobalt neodecanoate RC-D20;

[0022] The tackifying resin is tackifying resin 203;

[0023] The silane coupling agent is silane coupling agent Si-69.

[0024] The present invention provides a method for preparing the rubber composition described in the above technical solution, comprising the following steps:

[0025] The natural rubber, the reinforcing system, the silane coupling agent, the bonding system, the bonding promoter, the aging protection system, the cross-linking activation system, the plasticizing system and the tackifying resin are mixed in one stage to obtain a first-stage mixed material;

[0026] The first-stage mixed material and the cross-linking system are mixed in two stages to obtain the rubber composition.

[0027] Preferably, the time of the first stage mixing is 200 to 220 seconds; the time of the second stage mixing is 150 to 170 seconds.

[0028] The present invention provides the use of the above-mentioned rubber composition or the rubber composition prepared by the preparation method described in the above-mentioned technical scheme as a rubber coating for corrugated steel wires of aviation radial tires.

[0029] The invention provides a rubber composition, comprising the following raw materials in parts by mass: 100 parts of natural rubber, 78-100 parts of a reinforcing system, 1.2-1.5 parts of a silane coupling agent, 3.5-6 parts of an adhesive system, 0.3-0.5 parts of an adhesive promoter, 3.5-5.3 parts of an aging protection system, 2-5.7 parts of a crosslinking system, 6-6.5 parts of a crosslinking activation system, 5-8 parts of a plasticizing system, and 3-5 parts of a tackifying resin; the reinforcing system comprises carbon black and white carbon black; the adhesive system comprises a methylene donor and an adhesive RS; the aging protection system comprises a p-phenylenediamine antioxidant and a ketoamine antioxidant; the crosslinking system comprises insoluble sulfur, a sulfonamide accelerator and a scorch retarder; the crosslinking activation system comprises zinc oxide and stearic acid; and the plasticizing system comprises aromatic oil. The present invention adopts natural rubber as raw rubber system, and is combined with tackifying resin, reinforcing system, silane coupling agent, bonding system, bonding promoter, aging protection system, crosslinking system, crosslinking activation system, and plasticizing system, wherein: the reinforcing system adopts carbon black and white carbon black, and the rubber composition added with carbon black has higher tensile strength and tear resistance, and the surface of white carbon black particles has silanol structure, which plays a catalytic role in the generation of meta-formaldehyde system bonding resin, and can delay the vulcanization reaction of insoluble sulfur, so that the vulcanization reaction and the bonding reaction are carried out synchronously at the vulcanization temperature, and the bonding of rubber and fiber is improved. In addition, the addition of white carbon black increases the hardness, strength and wear resistance of rubber, and can also reduce the viscosity of rubber products, improve fluidity, and be convenient for processing and molding. Silane coupling agent can react chemically with the silanol on the surface of white carbon black, improve the tensile strength of vulcanized rubber, reduce permanent deformation rate and enhance wear resistance. The bonding system uses a methylene donor and an adhesive RS in combination with an adhesion promoter. Both the methylene donor and the adhesive RS are direct bonding meta-methyl-white bonding system agents. The adhesive RS can provide excellent performance toluene diphenol. The adhesion promoter can improve the adhesion and wear resistance of rubber and metal. Under vulcanization conditions, the meta-methyl-white bonding system agent will form a relatively complete resin network layer at the interface between rubber and steel cord. The perfect resin cross-linking network structure and its trapezoidal distribution in the vulcanized rubber compound will produce a strong chemical bond between the rubber compound and the steel cord, thereby improving the adhesion between the rubber compound and the steel cord. The aging protection system uses a combination of p-phenylenediamine antioxidants and ketoamine antioxidants. P-phenylenediamine antioxidants have excellent compatibility with rubber and have excellent protection against ozone and flex fatigue aging; while ketoamine antioxidants have a good protective effect against thermal oxidation aging and fatigue aging, and can also improve the adhesion between the rubber compound and the metal. The cross-linking system adopts a combination of insoluble sulfur, sulfonamide accelerators and scorch retardants. Compared with ordinary sulfur, insoluble sulfur has better stability. Sulfonamide accelerators not only have the advantages of thiazole accelerators, but also increase scorch retardants and active groups, which prolong the scorch time of the rubber, accelerate the vulcanization speed, and flatten the vulcanization curve. It has excellent comprehensive performance and safe operation.The scorch retarder effectively prolongs the scorch time of the rubber compound, ensuring that the rubber-coated rubber compound has enough time during the mixing and calendering process, thereby significantly improving the processing safety. In addition, the zinc oxide and stearic acid in the cross-linking activation system help to improve the cross-linking density and heat aging resistance of the vulcanized rubber. The plasticizing system uses aromatic oil to improve the processing performance of the semi-finished product and ensure the dimensional stability of the semi-finished product. In summary, the present invention can make the rubber rubber compound composition have good comprehensive performance by reasonably selecting the raw materials for preparing the rubber compound composition and setting the mass ratio of the raw materials for preparing the rubber compound composition. Compared with the traditional coating, the rubber compound composition provided by the present invention performs well in the properties such as compression fatigue temperature rise, tensile strength and elongation at break, and still maintains good adhesion after aging. The rubber compound composition provided by the present invention is used as the corrugated steel wire coating of the belt layer protective layer of the aviation radial tire. The tire will not produce the belt layer protective layer and the tread delamination, tread throwing, shoulder empty and other quality problems under the harsh high-speed and high-load use conditions, effectively improving the anti-foreign object puncture and mechanical damage performance of the aviation radial tire, and better guaranteeing the take-off and landing safety of the aircraft.

[0030] The present invention provides a method for preparing the rubber composition described in the above technical solution, comprising the following steps: mixing natural rubber, a reinforcing system, a silane coupling agent, an adhesive system, an adhesive promoter, an aging protection system, a crosslinking activation system, a plasticizing system and a tackifying resin in one stage to obtain a first-stage mixed material; and mixing the first-stage mixed material and the crosslinking system in two stages to obtain the rubber composition. The method for preparing the rubber composition provided by the present invention comprises two-stage mixing, and while ensuring the uniformity and stability of the rubber composition, the preparation method is simple and easy to implement, and is suitable for industrialized expansion of production. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a schematic diagram of the longitudinal structure of an aviation radial tire;

[0032] Figure 1 Middle: 1 is the belt layer protection layer, 2 is the belt layer, 3 is the carcass layer, 4 is the bead transition layer, 5 is the bead protection rubber, and 6 is the bead wire;

[0033] Figure 2 Schematic diagram of the arrangement structure of wavy steel cord fabric. DETAILED DESCRIPTION

[0034] The present invention provides a sizing composition, comprising the following raw materials in parts by weight:

[0035] 100 parts of natural rubber, 78-100 parts of reinforcement system, 1.2-1.5 parts of silane coupling agent, 3.5-6 parts of bonding system, 0.3-0.5 parts of adhesion promoter, 3.5-5.3 parts of aging protection system, 2-5.7 parts of cross-linking system, 6-6.5 parts of cross-linking activation system, 5-8 parts of plasticizing system, 3-5 parts of tackifying resin;

[0036] The reinforcement system includes carbon black and white carbon black;

[0037] The bonding system includes a methylene donor and an adhesive RS;

[0038] The aging protection system includes p-phenylenediamine antioxidant and ketoamine antioxidant;

[0039] The cross-linking system includes insoluble sulfur, sulfenamide accelerator and scorch retarder;

[0040] The cross-linking activation system includes zinc oxide and stearic acid;

[0041] The plasticizing system includes an aromatic oil.

[0042] In the present invention, unless otherwise specified, all preparation raw materials / components are commercially available products well known to those skilled in the art.

[0043] In parts by mass, the raw materials for preparing the rubber composition provided by the present invention include 100 parts of natural rubber. In the present invention, the natural rubber is domestic natural rubber. The natural rubber used in the embodiment of the present invention is purchased from Jiangcheng Co., Ltd. of Yunnan Natural Rubber Industry Group. The natural rubber used in the embodiment of the present invention is coagulated by natural rubber latex through microbial technology, which moderately reduces the protein content, thereby improving the tensile strength, elongation at break and tear strength, significantly reducing compression heat generation, and enhancing ozone aging resistance. Compared with ordinary domestic natural rubber, the natural rubber used in the embodiment of the present invention shows higher strength and elongation, lower heat generation and superior ozone aging resistance, ensuring the excellent performance of the tire under various harsh conditions. The natural rubber used in the rubber composition provided by the present invention is domestic natural rubber, which reduces the dependence on imported raw materials and improves the overall economic benefits. The present invention provides important support for the safety and reliability of aviation tires.

[0044] Based on the mass fraction of the natural rubber, the raw materials for preparing the rubber composition provided by the present invention include 78 to 100 parts of a reinforcing system, and specifically 80 parts, 84 parts or 98 parts in the embodiment. In the present invention, the reinforcing system includes carbon black and white carbon black. The carbon black is preferably carbon black N326, and the mass ratio of the carbon black to white carbon black is preferably (70 to 90): (8 to 10), and specifically 70:10, 76:8 or 90:8 in the embodiment. In the present invention, the reinforcing system in the rubber composition preferably includes 70 to 90 parts of carbon black and 8 to 10 parts of white carbon black, and specifically 70 parts, 76 parts or 90 parts of carbon black and 8 parts or 10 parts of white carbon black in the embodiment. In the present invention, carbon black N326 is a reinforcing carbon black, and the rubber composition to which carbon black N326 is added has higher tensile strength and tear strength.

[0045] Based on the mass fraction of the natural rubber, the raw materials for preparing the rubber composition provided by the present invention include 1.2 to 1.5 parts of a silane coupling agent, specifically 1.5 parts or 1.2 parts in the embodiment. In the present invention, the silane coupling agent is a silane coupling agent Si-69. In the present invention, the silane coupling agent Si-69 can chemically react with the silanol group on the surface of white carbon black to improve the tensile strength of the vulcanized rubber, reduce the permanent deformation rate and enhance the wear resistance.

[0046] Based on the mass fraction of the natural rubber, the raw materials for preparing the rubber composition provided by the present invention include 3.5 to 6 parts of the bonding system, specifically 4.5 parts, 6 parts or 5 parts in the embodiment. In the present invention, the bonding system includes a methylene donor and an adhesive RS. The methylene donor is preferably HMMM-55, and the mass ratio of the methylene donor to the adhesive RS is preferably (2 to 3): (1.5 to 3), specifically 3:1.5, 3:3 or 3:2 in the embodiment. In the present invention, the bonding system in the rubber composition preferably includes 2 to 3 parts of a methylene donor and 1.5 to 3 parts of an adhesive RS, specifically 3 parts of a methylene donor and 1.5 parts, 2 parts or 3 parts of an adhesive RS in the embodiment. In the present invention, HMMM-55 is a methylene donor with excellent performance. The adhesive HMMM-55 is a hexamethylol melamine (HMMM) product with a mass fraction of hexamethoxymelamine of 0.55.

[0047] Based on the mass fraction of the natural rubber, the raw materials for preparing the rubber composition provided by the present invention include 0.3 to 0.5 parts of an adhesion promoter, specifically 0.5 parts, 0.4 parts or 0.3 parts in the embodiment. In the present invention, the adhesion promoter is cobalt neodecanoate RC-D20. The cobalt neodecanoate RC-D20 can improve the adhesion and wear resistance between rubber and metal.

[0048] Under vulcanization conditions, the bonding system and bonding promoter provided by the present invention form a relatively complete resin network layer at the interface between the rubber and the steel cord. The complete resin cross-linked network structure and its trapezoidal distribution in the vulcanized rubber compound produce a strong chemical bond between the rubber compound and the steel cord, thereby improving the bonding between the rubber compound and the steel cord. Figure 2 Schematic diagram of the arrangement structure of wavy steel cord fabric.

[0049] Based on the mass fraction of the natural rubber, the raw materials for preparing the rubber composition provided by the present invention include 3.5 to 5.3 parts of the aging protection system, and specifically 4.3 or 4.5 parts in the embodiment. In the present invention, the aging protection system includes a p-phenylenediamine antioxidant and a ketoamine antioxidant; the p-phenylenediamine antioxidant is preferably a p-phenylenediamine antioxidant 4020, and the ketoamine antioxidant is preferably an antioxidant BLE; the mass ratio of the p-phenylenediamine antioxidant to the ketoamine antioxidant is preferably (2 to 3): (1.5 to 2.3), and specifically 2:2.3, 2.3:2 or 3:1.5 in the embodiment. In the present invention, the aging protection system in the rubber composition preferably includes 2 to 3 parts of a phenylenediamine antioxidant and 1.5 to 2.3 parts of a ketoamine antioxidant, and specifically 2 parts, 2.3 parts or 3 parts of a phenylenediamine antioxidant and 1.5 parts, 2 parts or 2.3 parts of a ketoamine antioxidant in the embodiment. In the present invention, the p-phenylenediamine antioxidant 4020 has excellent compatibility with rubber and has excellent protective performance against ozone and flexural fatigue aging; while the antioxidant BLE has a good protective effect against thermal oxygen aging and fatigue aging, and can also improve the adhesion between the rubber and the metal.

[0050] Based on the mass fraction of the natural rubber, the raw materials for preparing the rubber composition provided by the present invention include 2 to 5.7 parts of the crosslinking system, and specifically 5.7 parts, 3.7 parts or 3 parts in the embodiment. In the present invention, the crosslinking system includes insoluble sulfur, sulfonamide accelerators and scorch retarder; the insoluble sulfur is insoluble sulfur HDOT, the sulfonamide accelerator is sulfonamide accelerator DCBS-80, and the scorch retarder is scorch retarder CTP; the mass ratio of the insoluble sulfur, sulfonamide accelerator and scorch retarder is preferably (2 to 4): (0.8 to 1.5): 0.2, and specifically 4:1.5:0.2, 2.5:1:0.2 or 2:0.8:0.2 in the embodiment. In the present invention, the crosslinking system in the rubber composition preferably includes 2 to 4 parts of insoluble sulfur, 0.8 to 1.5 parts of sulfonamide accelerators and 0.2 parts of scorch retarder. In the embodiments, the crosslinking system includes 4 parts, 3.5 parts or 2 parts of insoluble sulfur, 0.8 parts, 1 part or 1.5 parts of sulfonamide accelerators and 0.2 parts of scorch retarder.

[0051] In the present invention, the cross-linking system adopts a combination of insoluble sulfur HDOT, accelerator DCBS-80 and anti-scorch agent CTP. Compared with ordinary sulfur, insoluble sulfur has better stability. Sulfonamide accelerator DCBS-80 not only has the advantages of thiazole accelerators, but also adds anti-scorch groups and active groups, which prolongs the scorch time of the rubber, accelerates the vulcanization speed, and flattens the vulcanization curve. It has excellent comprehensive performance and safe operation. Anti-scorch agent CTP effectively prolongs the scorch time of the rubber, ensuring that the coated rubber has enough time during the mixing and calendering process, thereby significantly improving processing safety.

[0052] Based on the mass fraction of the natural rubber, the raw materials for preparing the rubber composition provided by the present invention include 6 to 6.5 parts of a crosslinking activation system, and specifically 6.5 parts in the embodiment. In the present invention, the crosslinking activation system includes zinc oxide and stearic acid; the mass ratio of zinc oxide to stearic acid is 5:(1 to 1.5), and specifically 5:1.5 in the embodiment. In the present invention, the crosslinking activation system in the rubber composition preferably includes 5 parts of zinc oxide and 1 to 1.5 parts of stearic acid, and specifically 5 parts of zinc oxide and 1.5 parts of stearic acid in the embodiment. In the present invention, zinc oxide and stearic acid in the crosslinking activation system help to improve the crosslinking density and heat aging resistance of vulcanized rubber.

[0053] Based on the mass fraction of the natural rubber, the raw materials for preparing the rubber composition provided by the present invention include 5 to 8 parts of a plasticizer system, specifically 8 parts, 7 parts or 5 parts in the embodiments. In the present invention, the plasticizer system includes aromatic oil.

[0054] Based on the mass fraction of the natural rubber, the raw materials for preparing the rubber composition provided by the present invention include 3 to 5 parts of tackifying resin, specifically 3 parts or 5 parts in the embodiment. The tackifying resin is tackifying resin 203.

[0055] The rubber composition provided by the present invention preferably comprises the following raw materials in parts by weight:

[0056] 100 parts of natural rubber, 8-10 parts of white carbon black, 1.2-1.5 parts of silane coupling agent Si-69, 70-90 parts of carbon black N326, 0.3-0.5 parts of cobalt neodecanoate RC-D20, 2-3 parts of HMMM-55, 1.5-3 parts of adhesive RS, 3-5 parts of tackifying resin 203, 5 parts of zinc oxide, 1.5 parts of stearic acid, 2-3 parts of p-phenylenediamine antioxidant 4020, 1.5-2.3 parts of antioxidant BLE, 5-8 parts of aromatic oil, 2-4 parts of insoluble sulfur HDOT, 0.8-1.5 parts of sulfonamide accelerator DCBS-80, and 0.2 parts of anti-scorch agent CTP. The rubber composition provided by the present invention has the characteristics of low heat generation and small hysteresis loss, and significantly improves the service life and safety performance of aviation radial tires.

[0057] The present invention provides a method for preparing the rubber composition described in the above technical solution, comprising the following steps:

[0058] The natural rubber, the reinforcing system, the silane coupling agent, the bonding system, the bonding promoter, the aging protection system, the cross-linking activation system, the plasticizing system and the tackifying resin are mixed in one stage to obtain a first-stage mixed material;

[0059] The first-stage mixed material and the cross-linking system are mixed in two stages to obtain the rubber composition.

[0060] The present invention performs a one-stage mixing of natural rubber, a reinforcement system, a silane coupling agent, an adhesive system, an adhesion promoter, an aging protection system, a cross-linking activation system, a plasticizing system and a tackifying resin to obtain a one-stage mixed material. In the present invention, the time of the one-stage mixing is 200 to 220 seconds, and specifically 200 seconds in the embodiment. The one-stage mixing preferably includes the following steps: pre-mixing the natural rubber to obtain a pre-mixed natural rubber; first mixing the pre-mixed natural rubber, a part of the reinforcement system and a silane coupling agent to obtain a first mixed material; second mixing the first mixed material, the aging protection system, the tackifying resin, the adhesive system and the adhesion promoter to obtain a second mixed material; third mixing the second mixed material, the remaining reinforcement system and the plasticizing system to obtain a one-stage mixed material. The pre-mixing, the first mixing, the second mixing and the third mixing are performed in an internal mixer, and the temperature of the pre-mixed natural rubber is preferably 80°C. The part of the reinforcement system is preferably white carbon black. The temperature of the first mixed material is preferably 90°C. The temperature of the second mixed material is preferably 110° C. The remaining reinforcement system is carbon black. The temperature of the third mixed material is preferably 130° C.

[0061] After obtaining the first-stage mixed material, the present invention preferably further comprises: subjecting the first-stage mixed material to sheeting, rolling and cooling and parking in sequence to obtain a cooled first-stage mixed material. The cooled first-stage mixed material is subjected to the second-stage mixing. The sheeting and rolling are performed in a tablet press, and the number of rolling is preferably 2 times. The cooling and parking time is preferably 16 to 24 hours.

[0062] After obtaining a first-stage mixed material or a cooled first-stage mixed material, the present invention performs two-stage mixing on the first-stage mixed material or the cooled first-stage mixed material and the cross-linking system to obtain the rubber composition. In the present invention, the time of the two-stage mixing is 150 to 170 seconds, and specifically 170 seconds in the embodiment. The two-stage mixing preferably includes the following steps: performing a fourth mixing on the first-stage mixed material and the cross-linking system to obtain a two-stage mixed material. After obtaining the two-stage mixed material, the present invention preferably also includes: sequentially sheeting and cooling the two-stage mixed material to obtain a cooled two-stage mixed material. The fourth mixing is performed in an internal mixer. The temperature of the fourth mixed material is preferably 105°C. The sheeting is performed in a tablet press.

[0063] The rubber composition provided by the present invention adopts natural rubber as the raw rubber system, and is combined with various materials such as the above-mentioned reinforcing carbon black, white carbon black, silane coupling agent, sulfonamide accelerator and new meta-methyl-white bonding system, and is made according to a specific ratio. The preparation method of the rubber composition provided by the present invention includes a two-stage mixing process to ensure the uniformity and stability of the rubber. Compared with traditional coating rubber, the rubber composition provided by the present invention performs excellently in properties such as compression fatigue temperature rise, tensile strength and elongation at break, and still maintains good adhesion after aging, effectively enhancing the tire's anti-puncture ability and service life. In addition, the rubber composition provided by the present invention adopts domestic natural rubber, which reduces dependence on imported raw materials and improves overall economic benefits. The invention provides important support for the safety and reliability of aviation tires.

[0064] The present invention provides the use of the above-mentioned rubber composition or the rubber composition prepared by the preparation method described in the above-mentioned technical scheme as a rubber coating for corrugated steel wires of aviation radial tires.

[0065] The rubber composition provided by the present invention is used as a rubber coating for corrugated steel wires of aviation radial tires, and has the following significant advantages compared with the prior art:

[0066] (1) The rubber composition of the corrugated steel wire coating (rubber composition) of the present invention has excellent bonding performance with the steel cord before and after aging, ensuring that the external load can be effectively transferred to the skeleton material of the tire under complex service conditions. The bonding of the rubber composition provided by the present invention with the steel cord fully releases the load-bearing potential of the steel cord, significantly enhances the puncture resistance of the tire, and effectively tightens the belt layer, thereby providing a solid guarantee for the safety and reliability of the aircraft.

[0067] (2) The rubber composition provided by the present invention uses domestic natural rubber, successfully breaking through the bottleneck of dependence on imported raw materials. Compared with imported natural rubber, domestic high-end natural rubber has more significant advantages in quality stability and supply chain reliability. Its excellent comprehensive performance greatly reduces the quality risks such as debonding of the belt layer protective layer in a complex thermal alternating environment, and can adapt to the stringent performance requirements of future new aviation tires for high speed and high load.

[0068] (3) The rubber composition provided by the present invention as a belt layer protective layer coating has the characteristics of low heat generation and small hysteresis loss, which effectively prevents delamination and shoulder voids of the tire belt layer protective layer, thereby significantly improving the service life and safety performance of the aviation radial tire.

[0069] (4) In addition, the rubber composition provided by the present invention exhibits excellent tensile properties and can maintain excellent performance stability in a high-intensity working environment, significantly extending the service life of the tire, reducing maintenance costs, and improving overall economic benefits.

[0070] In order to further illustrate the present invention, the technical solutions provided by the present invention are described in detail below in conjunction with embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0071] Examples 1 to 3 and Comparative Example 1

[0072] The raw materials used in the rubber compositions provided in Examples 1 to 3 and Comparative Example 1 and the weight percentage of each raw material are shown in Table 1. The amount of each raw material in Table 1 is in weight percentage.

[0073] Table 1 Amount of each raw material in the rubber composition provided in Examples 1 to 3 and Comparative Example 1

[0074] Raw material name Example 1 Example 2 Example 3 Comparative Example 1 Domestic high-end natural rubber 100 100 100 100 White Carbon Black 10 8 8 8 N326 Carbon Black 70 76 90 76 Silane coupling agent Si-69 1.5 1.2 1.2 0.5 Cobalt Neodecanoate RC-D20 0.5 0.4 0.3 0.4 HMMM-55 3 3 3 1 Adhesive RS 1.5 2.0 3.0 2.0 Tackifying resin 203 3 3 5 3 Zinc Oxide 5 5 5 5 Stearic acid 1.5 1.5 1.5 1.5 Antioxidant 4020 2.0 2.3 3.0 2.3 Antioxidant BLE 2.3 2.0 1.5 0.5 Aromatic oil 8 7 5 7 Insoluble sulfur HDOT 4.0 2.5 2.0 2.5 Accelerator DCBS-80 1.5 1.0 0.8 1.0 Anti-scorch agent CTP 0.2 0.2 0.2 0.2

[0075] In Examples 1 to 3 and Comparative Example 1, the domestically produced high-end natural rubber used was sourced from Yunnan Natural Rubber Industry Group Jiangcheng Co., Ltd.

[0076] The preparation method of the sizing composition provided in Examples 1 to 3 and Comparative Example 1 specifically comprises the following steps:

[0077] (1) One-stage mixing:

[0078] 1) Add natural rubber into an internal mixer for plasticization, and raise the temperature to 80°C;

[0079] 2) adding white carbon black and silane coupling agent Si-69 to the natural rubber in step 1), mixing and kneading, and raising the temperature to 90° C.;

[0080] 3) Add zinc oxide, stearic acid, antioxidant 4020, antioxidant BLE, tackifying resin 203, adhesive RS, HMMM-55, and cobalt neodecanoate RC-D20 to the mixed material in step 2), mix and knead, and raise the temperature to 110° C.;

[0081] 4) Add N326 carbon black and aromatic oil to the mixed material in step 3), mix and knead, raise the temperature to 130°C, and obtain a first-stage mixed material, wherein the total mixing time of the first-stage mixing is 200s. The first-stage mixed material is discharged from the internal mixer to a tablet press for unrolling, and after two roll pressings, cooled and parked for 16 to 24 hours to obtain a cooled first-stage mixed material.

[0082] (2) Second stage mixing:

[0083] Insoluble sulfur HDOT, accelerator DCBS-80, anti-scorch agent CTP, and the cooled first-stage mixed material obtained in step (1) are added to an internal mixer, mixed and mixed to 105° C., and the mixed materials are discharged from the internal mixer to obtain a second-stage mixed material, wherein the mixing time of the second-stage mixing is 170 seconds. The second-stage mixed material is put into a tablet press for unrolling, cooled and parked, and a rubber composition is obtained, namely, a belt layer protective layer steel wire coating rubber mixed rubber.

[0084] The present invention performs performance tests on the rubber compositions (i.e., rubber coating on corrugated steel wire) prepared in Examples 1 to 3 and Comparative Example 1. The properties of the rubbers prepared in Examples 1 to 3 and Comparative Example 1 are shown in Table 2.

[0085] Table 2 Performance of the rubber materials obtained in Examples 1 to 3 and Comparative Example 1

[0086]

[0087] From the performance results in Table 2, it can be seen that the corrugated steel wire rubber coating provided by the present invention has good mechanical properties, low heat generation, and good adhesion performance with steel cord cords.

[0088] From the above examples, it can be seen that the present invention can make the rubber compound composition have good comprehensive performance by reasonably selecting the raw materials for preparing the rubber compound composition and setting the mass ratio of the raw materials for preparing the rubber compound composition. Compared with the traditional coating, the rubber compound composition provided by the present invention performs well in the properties such as compression fatigue temperature rise, tensile strength and elongation at break, and still maintains good adhesion after aging. The rubber compound composition provided by the present invention is used as the corrugated steel wire coating of the belt layer protective layer of the aviation radial tire. The tire will not produce quality problems such as delamination of the belt layer protective layer and the tread, tread throwing, and shoulder void under harsh high-speed and high-load conditions of use, effectively improving the performance of the aviation radial tire against foreign object puncture and mechanical damage, and better ensuring the take-off and landing safety of the aircraft.

[0089] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A rubber composition, characterized in that: The preparation comprises the following raw materials in parts by weight: 100 parts of natural rubber, 78-100 parts of reinforcement system, 1.2-1.5 parts of silane coupling agent, 3.5-6 parts of bonding system, 0.3-0.5 parts of adhesion promoter, 3.5-5.3 parts of aging protection system, 2-5.7 parts of cross-linking system, 6-6.5 parts of cross-linking activation system, 5-8 parts of plasticizing system, 3-5 parts of tackifying resin; The reinforcement system includes carbon black and white carbon black; The bonding system includes a methylene donor and an adhesive RS; The aging protection system includes p-phenylenediamine antioxidant and ketoamine antioxidant; The cross-linking system includes insoluble sulfur, sulfenamide accelerator and scorch retarder; The cross-linking activation system includes zinc oxide and stearic acid; The plasticizing system includes an aromatic oil.

2. The rubber composition according to claim 1, characterized in that: The carbon black is carbon black N326, and the mass ratio of the carbon black to white carbon black is (70-90):(8-10).

3. The rubber composition according to claim 1, characterized in that: The methylene donor is HMMM-55, and the mass ratio of the methylene donor to the adhesive RS is (2-3): (1.5-3).

4. The rubber composition according to claim 1, characterized in that: The p-phenylenediamine antioxidant is p-phenylenediamine antioxidant 4020, and the ketoamine antioxidant is antioxidant BLE; the mass ratio of the p-phenylenediamine antioxidant to the ketoamine antioxidant is (2-3): (1.5-2.3).

5. The rubber composition according to claim 1, characterized in that: The insoluble sulfur is insoluble sulfur HDOT, the sulfonamide accelerator is sulfonamide accelerator DCBS-80, and the anti-scorch agent is anti-scorch agent CTP; the mass ratio of the insoluble sulfur, the sulfonamide accelerator and the anti-scorch agent is (2-4): (0.8-1.5): 0.

2.

6. The rubber composition according to claim 1, characterized in that: The mass ratio of the zinc oxide to stearic acid is 5:(1-1.5).

7. The rubber composition according to claim 1, characterized in that: The adhesion promoter is cobalt neodecanoate RC-D20; The tackifying resin is tackifying resin 203; The silane coupling agent is silane coupling agent Si-69.

8. The method for preparing the sizing composition according to any one of claims 1 to 7, characterized in that: The following steps are involved: The natural rubber, the reinforcing system, the silane coupling agent, the bonding system, the bonding promoter, the aging protection system, the cross-linking activation system, the plasticizing system and the tackifying resin are mixed in one stage to obtain a first-stage mixed material; The first-stage mixed material and the cross-linking system are mixed in two stages to obtain the rubber composition.

9. The preparation method according to claim 8, characterized in that: The time of the first stage mixing is 200 to 220 seconds; the time of the second stage mixing is 150 to 170 seconds.

10. Use of the rubber composition according to any one of claims 1 to 7 or the rubber composition prepared by the preparation method according to claim 8 or 9 as a rubber coating for corrugated steel wires of aviation radial tires.

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