Tip protection rubber composition, preparation method thereof and application in tire preparation

Abstract

The present invention provides a rubber composition for a sprocket and a preparation method thereof and an application thereof in preparing a tire, and relates to the technical field of tire manufacturing. The raw materials of the rubber composition for a sprocket include: raw rubber, carbon black and a vulcanizing agent; wherein the raw rubber includes diene rubber and chloroprene rubber, and the vulcanizing agent includes an organic vulcanizing agent. The composition improves the mechanical properties and the heat aging resistance of the rubber for a sprocket by using chloroprene rubber and diene rubber together, and at the same time, an organic vulcanizing machine is used to improve the fatigue resistance of the rubber for a sprocket, and the brittleness problem caused by high rigidity is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of tire manufacturing, in particular to a tire mouth protective rubber composition and a preparation method thereof and application in tire preparation. Background Art

[0002] During tire manufacturing and use, the bead guard, as the contact point between the tire and the rim, is an important stress-bearing component. Its function is to prevent the tire bead from wearing out due to repeated extension and compression between the tire and the rim. The stress it bears is significantly higher than that of other components, requiring it to have higher hardness, rigidity and wear resistance. During the driving process of the tire, the rubber parts will be repeatedly stressed and heat will accumulate. In particular, the temperature of the rim rises sharply during braking, and the heat is transferred to the bead guard, which can easily lead to bead voids and cracks, thereby causing tire failure. Therefore, the bead guard is required to have excellent heat aging resistance and low heat generation.

[0003] Invention patent CN116199947A discloses a method of using EPDM rubber impregnated with modified glass short fibers to improve the heat resistance of the nozzle protective rubber, but ignores the nozzle brittle cracking caused by the inherent brittleness of the glass short fibers, which limits its application range and actual effect.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] One of the purposes of the present invention is to provide a rubber composition for a sub-mouth protection to at least solve one of the technical problems existing in the prior art. The raw materials of the rubber composition for a sub-mouth protection include: raw rubber, carbon black and a vulcanizing agent; wherein the raw rubber includes diene rubber and chloroprene rubber, and the vulcanizing agent includes an organic vulcanizer. The composition improves the mechanical properties and the heat aging resistance of the sub-mouth protection rubber by using chloroprene rubber and diene rubber together, and at the same time, an organic vulcanizer is used to improve the fatigue resistance of the sub-mouth protection rubber, avoiding the brittleness problem caused by high rigidity.

[0006] The second object of the present invention is to provide a method for preparing a rubber compound for a rubber mouth. The method can achieve high-quality blending of the rubbers and improve the process and dispersibility by adding a portion of dual-phase carbon black to the rubber in advance.

[0007] The third object of the present invention is to provide a tire bead protection rubber composition or the use of the tire bead protection rubber composition prepared by the preparation method in the preparation of tires.

[0008] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0009] In a first aspect, the present invention provides a rubber compound for protecting a sub-mouth, wherein the raw materials of the rubber compound for protecting a sub-mouth include: raw rubber, carbon black and a vulcanizing agent;

[0010] Wherein, the raw rubber includes diene rubber and chloroprene rubber, and the vulcanizing agent includes an organic vulcanizing agent.

[0011] Further, the diene rubber includes at least one of natural rubber and butadiene rubber;

[0012] Preferably, the raw material components of the sub-mouth protection rubber composition include: 100phr raw rubber, 70-80phr carbon black and 1.0-2.0phr vulcanizing agent;

[0013] Preferably, the raw rubber comprises 30-50 phr natural rubber, 30-50 phr butadiene rubber and 10-30 phr chloroprene rubber.

[0014] Further, the carbon black includes SX7 series dual-phase carbon black;

[0015] Preferably, the carbon black includes at least one of SX71 carbon black and SX72 carbon black.

[0016] Furthermore, the vulcanizing agent also includes an inorganic vulcanizing agent;

[0017] Preferably, the inorganic vulcanizing agent comprises sulfur;

[0018] Preferably, the organic vulcanizer comprises hexamethylene-1,6-bisthiosulfate disodium salt.

[0019] Furthermore, the raw materials of the sub-mouth protective glue composition also include a softener, a protective wax, an antioxidant, an activator and a accelerator;

[0020] Preferably, the softener comprises at least one of aromatic oil, tert-butylphenol-formaldehyde resin and octylphenol-formaldehyde resin;

[0021] Preferably, the antioxidant includes at least one of antioxidant 4020 and antioxidant RD;

[0022] Preferably, the activator comprises at least one of stearic acid and zinc oxide;

[0023] Preferably, the accelerator comprises at least one of sulfenamide NS and sulfenamide CZ.

[0024] Furthermore, the raw material components of the sub-mouth protective glue composition also include: 1.0-2.0 phr inorganic vulcanizing agent, 1.0-2.0 phr organic vulcanizing agent, 3.0-8.0 phr softener, 0.5-2.0 phr protective wax, 1.5-3.0 phr antioxidant 4020, 0.5-1.0 phr antioxidant RD, 4.0-6.0 phr activator and 1-2.5 phr accelerator.

[0025] In a second aspect, the present invention provides a method for preparing a sub-mouth protective glue composition, comprising the following steps:

[0026] The natural rubber, chloroprene rubber and part of the carbon black are mixed once, and then the butadiene rubber is added for a second mixing to obtain a masterbatch, and then the masterbatch and the remaining carbon black are mixed for a third time, and then a softener, a protective wax, an antioxidant and an activator are added for a fourth mixing, and then a vulcanizer and an accelerator are added for a fifth mixing to obtain the sub-mouth protective rubber composition.

[0027] Furthermore, the amount of the partial carbon black added is 1 / 5-2 / 5 of the total amount of carbon black added.

[0028] Furthermore, the spout protection glue composition is prepared by a mixing process;

[0029] Preferably, the primary mixing includes compacting and kneading, and the compacting time is 30-40s;

[0030] Preferably, the secondary mixing comprises: adding butadiene rubber to perform compacting and mixing until the temperature reaches 140-150° C. and then performing debonding;

[0031] Preferably, the three-stage mixing comprises: mixing the masterbatch and the remaining carbon black to perform compacting and kneading;

[0032] Preferably, the four-step mixing comprises: when the temperature of the three-step mixing reaches 115°C-125°C, adding a softener, a protective wax, an antioxidant and an activator to perform compaction mixing for 25-35s, and performing debonding when the temperature reaches 155°C-165°C;

[0033] Preferably, the five mixing steps include: pressing and mixing until the temperature reaches 105-115° C. and then performing debinding;

[0034] Preferably, the five mixing steps include at least two pressing and kneading steps, the first pressing and kneading step lasts for 30-40 seconds, and the second pressing and kneading step lasts for 30-40 seconds.

[0035] In a third aspect, the present invention provides a tire bead protection rubber composition or a tire bead protection rubber composition prepared by the preparation method and its use in preparing a tire.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] The tire bead protection rubber composition provided by the present invention uses chloroprene rubber in the tire bead protection rubber and is used in combination with diene rubber to improve the mechanical properties and the heat aging resistance of the tire bead protection rubber; dual-phase carbon black is also added to the tire bead protection rubber composition to reduce heat generation while ensuring the mechanical properties of the tire bead protection rubber; and an effective vulcanization system is used to reduce the poor aging resistance problem caused by polysulfide bonds, and the introduced flexible organic vulcanizing agent generates sulfur-carbon mixed cross-linking bonds to further improve the heat aging resistance of the tire bead protection rubber. At the same time, the introduced flexible chain can better adapt to the brittle cracking problem caused by the reciprocating stress and strain of the tire and the high rigidity of the tire bead protection rubber. DETAILED DESCRIPTION

[0038] Unless otherwise defined herein, scientific and technical terms used in conjunction with the present invention shall have the meanings commonly understood by those of ordinary skill in the art. The meaning and scope of the terms should be clear, however, in the case of any potential ambiguity, the definitions provided herein take precedence over any dictionary or external definitions. In this application, unless otherwise stated, the use of "or" means "and / or". In addition, the use of the term "including" and other forms is non-limiting.

[0039] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] The first aspect of the present invention provides a rubber compound for protecting the sub-mouth, wherein the raw materials of the rubber compound for protecting the sub-mouth include: raw rubber, carbon black and a vulcanizing agent;

[0041] Wherein, the raw rubber includes diene rubber and chloroprene rubber, and the vulcanizing agent includes an organic vulcanizer.

[0042] The tire bead rubber composition provided by the present invention is a heat-resistant and low-heat-generating tire bead rubber composition. Chloroprene rubber is usually used for flame-retardant materials. The presence of Cl in its molecular structure inhibits the activity of double bonds, thereby making the aging resistance and ozone resistance far superior to those of ordinary diene rubbers. Meanwhile, the chloroprene rubber has good mechanical properties and is better than natural rubber in long-term wear resistance. The chloroprene rubber is used in the tire bead rubber together with diene rubber to improve the mechanical properties and the heat aging resistance of the tire bead rubber. Carbon black is also added to the tire bead rubber composition to reduce heat generation while ensuring the mechanical properties of the tire bead rubber. Furthermore, an effective vulcanization system is used to reduce the problem of poor aging resistance caused by polysulfide bonds. The introduced flexible organic vulcanizing agent generates sulfur-carbon mixed cross-linking bonds to further improve the heat aging resistance of the tire bead rubber. Meanwhile, the introduced flexible chain can better adapt to the brittle cracking problem caused by the reciprocating stress strain of the tire and the high rigidity of the tire bead rubber.

[0043] In some preferred embodiments, the diene rubber includes at least one of natural rubber and butadiene rubber;

[0044] In the present invention, chloroprene rubber is used in combination with natural rubber and butadiene rubber, so as to improve the mechanical properties of the spout rubber composition and improve the heat aging resistance and wear resistance of the spout rubber.

[0045] Preferably, the raw material components of the sub-mouth protection rubber composition include: 100phr raw rubber, 70-80phr carbon black and 1.0-2.0phr vulcanizing agent;

[0046] Wherein, in the sub-mouth protective rubber composition, the amount of carbon black added is 70phr, 71phr, 72phr, 73phr, 74phr, 75phr, 76phr, 77phr, 78phr, 79phr, 80phr, etc.;

[0047] Among them, in the sub-mouth protective rubber composition, the added amount of the vulcanizer is 1.0phr, 1.1phr, 1.2phr, 1.3phr, 1.4phr, 1.5phr, 1.6phr, 1.7phr, 1.8phr, 1.9phr, 2.0phr, etc.

[0048] Preferably, the raw rubber comprises 30-50 phr natural rubber, 30-50 phr butadiene rubber and 10-30 phr chloroprene rubber.

[0049] Wherein, in the spout rubber protection composition, the addition amount of the natural rubber is 30phr, 35phr, 40phr, 45phr, 50phr, etc.;

[0050] Wherein, in the sub-mouth protective rubber composition, the addition amount of the butadiene rubber is 30phr, 35phr, 40phr, 45phr, 50phr, etc.;

[0051] Among them, in the sub-mouth protective rubber composition, the added amount of the chloroprene rubber is 10phr, 15phr, 20phr, 25phr, 30phr, etc.

[0052] In some preferred embodiments, the carbon black includes SX7 series dual-phase carbon black;

[0053] Preferably, the carbon black includes at least one of SX71 carbon black and SX72 carbon black.

[0054] In the present invention, the use of low heat generation dual-phase carbon black can improve the physical and mechanical properties of the rubber material, reduce the hysteresis loss of the rubber material and reduce the heat generation. At the same time, the present invention uses SX7 series dual-phase carbon black and chloroprene rubber to be synchronously applied to the tire bead protection rubber. Carbon black is used as a filler. The polar hydroxyl group on the surface of the SX7 series dual-phase carbon black and the polar group -Cl of the chloroprene rubber coordinate and interact with each other, which greatly improves the interaction between the filler and the polymer, improves the mechanical properties, and greatly reduces the aggregation of the filler and reduces the Payne effect, so as to comprehensively give the rubber composition high strength and low heat generation characteristics.

[0055] In some preferred embodiments, the vulcanizing agent further comprises an inorganic vulcanizing agent;

[0056] Preferably, the inorganic vulcanizing agent comprises sulfur;

[0057] Preferably, the organic vulcanizer comprises hexamethylene-1,6-bisthiosulfate disodium salt.

[0058] In the present invention, an effective vulcanization system (organic vulcanizing agent and inorganic vulcanizing agent are used in combination) is adopted to reduce the poor aging resistance problem caused by polysulfide bonds. At the same time, the flexible organic vulcanizing agent is introduced to generate sulfur-carbon mixed cross-linking bonds to further improve the heat aging resistance of the rubber cap. At the same time, the introduced flexible chain can better adapt to the brittle cracking problem caused by the reciprocating stress and strain of the tire and the high rigidity of the rubber cap.

[0059] In some preferred embodiments, the raw materials of the sub-mouth protective glue composition also include a softener, a protective wax, an antioxidant, an activator and an accelerator;

[0060] Preferably, the softener comprises at least one of aromatic oil, tert-butylphenol-formaldehyde resin and octylphenol-formaldehyde resin;

[0061] Preferably, the antioxidant includes at least one of antioxidant 4020 and antioxidant RD;

[0062] Preferably, the activator comprises stearic acid and zinc oxide;

[0063] Preferably, the accelerator comprises at least one of sulfenamide NS and sulfenamide CZ.

[0064] In some preferred embodiments, the raw material components of the sub-mouth protective glue composition also include: 1.0-2.0 phr inorganic vulcanizing agent, 1.0-2.0 phr organic vulcanizing agent, 3.0-8.0 phr softener, 0.5-2.0 phr protective wax, 1.5-3.0 phr antioxidant 4020, 0.5-1.0 phr antioxidant RD, 4.0-6.0 phr activator and 1-2.5 phr accelerator.

[0065] Wherein, in the sub-mouth protective glue composition, the addition amount of the inorganic vulcanizing agent is 1.0phr, 1.5phr, 2.0phr, etc.;

[0066] Wherein, in the sub-mouth protective glue composition, the addition amount of the organic vulcanizing agent is 1.0phr, 2.0phr, etc.;

[0067] Wherein, in the sub-mouth protective glue composition, the addition amount of the softener is 3.0phr, 4.0phr, 5.0phr, 6.0phr, 7.0phr, 8.0phr, etc.;

[0068] Wherein, in the sub-mouth protective glue composition, the added amount of the protective wax is 0.5, 1.0, 1.5, 2.0, etc.;

[0069] Among them, in the sub-mouth protective glue composition, the addition amount of the antioxidant 4020 is 1.5phr, 2.0phr, 2.5phr, 3.0phr, etc.;

[0070] Wherein, in the sub-mouth protective glue composition, the addition amount of the antioxidant RD is 0.5phr, 0.6phr, 0.7phr, 0.8phr, 0.9phr, 1.0phr, etc.;

[0071] Wherein, in the sub-mouth protective glue composition, the added amount of the activator is 4.0phr, 5.0phr, 6.0phr, etc.;

[0072] Among them, in the sub-mouth protective glue composition, the added amount of the accelerator is 1phr, 1.5phr, 2phr, 2.5phr, etc.

[0073] It should be noted that, according to conventional practice, in the rubber field, "phr" is a commonly used unit of measurement, and the term "phr" means "parts by weight of the corresponding material per 100 parts by weight of the rubber matrix". Usually, using this convention, the rubber composition for the spout contains 100 parts by weight of the rubber matrix. Unless otherwise indicated, the terms "rubber matrix" and "raw rubber" may also be used interchangeably herein.

[0074] The second aspect of the present invention provides a method for preparing the sub-mouth protective glue composition, comprising the following steps:

[0075] The natural rubber, chloroprene rubber and part of the carbon black are mixed once, and then the butadiene rubber is added for a second mixing to obtain a masterbatch, and then the masterbatch and the remaining carbon black are mixed for a third time, and then a softener, a protective wax, an antioxidant and an activator are added for a fourth mixing, and then a vulcanizer and an accelerator are added for a fifth mixing to obtain the sub-mouth protective rubber composition.

[0076] In the present invention, by pre-adding a small amount of SX series dual-phase carbon black for plasticization, on the one hand, the carbon black active points retained in the dual-phase carbon black can be well combined with the natural rubber, and on the other hand, the polar hydroxyl part in the dual-phase carbon black can be well combined with the polar chloroprene rubber, so that the non-polar natural rubber and the polar chloroprene rubber can be blended with high quality, and the process and dispersibility are improved.

[0077] In some preferred embodiments, the amount of the partial carbon black added is 1 / 5-2 / 5 of the total amount of carbon black added.

[0078] In some preferred embodiments, the spout protection glue composition is prepared by a mixing process;

[0079] Preferably, the primary mixing includes pressing and kneading, and the pressing time is 30-40s, for example, 30s, 35s, 40s, etc.;

[0080] Preferably, the secondary mixing comprises: adding butadiene rubber for compacting and mixing, and performing rubber removal at a temperature of 140-150° C., which temperature may be, for example, 140° C., 145° C., 150° C., etc.;

[0081] Preferably, the three-stage mixing comprises: mixing the masterbatch and the remaining carbon black to perform compacting and kneading;

[0082] Preferably, the four mixings include: when the temperature of the three mixings reaches 115°C-125°C, the temperature may be, for example, 115°C, 120°C, 125°C, etc., then adding a softener, protective wax, antioxidant and activator to perform compaction and mixing for 25-35s, for example, 25s, 30s, 35s, etc., until the temperature reaches 155°C-165°C for debinding, the temperature may be, for example, 155°C, 160°C, 165°C, etc.;

[0083] Preferably, the five mixing steps include: pressing and mixing until the temperature reaches 105-115° C. and then performing binder removal, and the temperature may be, for example, 105° C., 110° C., 115° C., etc.;

[0084] Preferably, the five mixings include at least two pressing and kneading, the first pressing and kneading time is 30-40s, for example, 30s, 35s, 40s, etc., and the second pressing and kneading time is 30-40s, for example, 30s, 35s, 40s, etc.

[0085] Furthermore, the preparation method of the spout protection glue composition is prepared by a mixing method, including multi-stage mixing, specifically comprising the following steps:

[0086] The first stage of master batching: add natural rubber, chloroprene rubber and part of carbon black, press the ball for 30-40 seconds, remove the ball and clean it, add butadiene rubber, press the ball again and mix it, and discharge the rubber at 140-150℃;

[0087] The second stage of mixing: add the first stage of masterbatch and the remaining reinforcing filler (i.e. the remaining carbon black), press and mix to 115℃-125℃, add softener, protective wax, antioxidant and activator, press and mix for 25-35s, lift the lump for cleaning, and press and mix again to 155℃-165℃ for debonding;

[0088] The third mixing stage: add the second-stage mixed rubber, inorganic vulcanizer, organic vulcanizer and accelerator, press the ball and keep it for 30-40 seconds, lift the ball and clean it, press the ball again and keep it for 30-40 seconds, lift the ball and clean it, and press the ball again to mix it to 105-115℃ for rubber discharge.

[0089] The third aspect of the present invention provides a use of the tire bead protection rubber composition or the tire bead protection rubber composition prepared by the preparation method in preparing a tire.

[0090] In the present invention, the tire is preferably an all-steel radial tire, and the wear-resistant rubber of the tire is prepared by vulcanizing the described rubber composition for the sprocket.

[0091] The present invention is further described below by way of examples. Unless otherwise specified, the materials in the examples are prepared according to existing methods or directly purchased from the market.

[0092] The SX series duplex carbon black in the examples and comparative examples of the present invention is prepared by the preparation method in Chinese invention patent CN112080161B, such as the carbon black prepared in Example 3 in CN112080161B.

[0093] Example 1

[0094] This embodiment provides a mouth protection glue composition, the raw material components of which include:

[0095] Natural rubber 50phr, butadiene rubber 40phr, chloroprene rubber 10phr, SX72 78phr, softener (specifically aromatic oil) 4phr, stearic acid 2phr, zinc oxide 3.5phr, antioxidant 4020 2.5phr, antioxidant RD 0.5phr, protective wax 0.5phr, sulfur 1.0phr, accelerator (specifically sulfonamide NS) 2.2phr, organic vulcanizing agent hexamethylene-1,6-bisthiosulfate disodium salt 1.0phr.

[0096] Example 2

[0097] This embodiment provides a mouth protection glue composition, the raw material components of which include:

[0098] Natural rubber 40phr, butadiene rubber 40phr, chloroprene rubber 20phr, SX72 76phr, softener (specifically selected is tert-butyl phenolic resin) 6phr, stearic acid 2phr, zinc oxide 3.5phr, antioxidant 4020 2phr, antioxidant RD0.5phr, protective wax 1.0phr, sulfur 1.0phr, accelerator (specifically selected is sulfonamide CZ) 2.2phr, organic vulcanizing agent hexamethylene-1,6-bisthiosulfate disodium salt 2.0phr.

[0099] Example 3

[0100] This embodiment provides a mouth protection glue composition, the raw material components of which include:

[0101] Natural rubber 40phr, butadiene rubber 30phr, chloroprene rubber 30phr, SX72 73phr, softener (specifically octyl phenolic resin) 8phr, stearic acid 2phr, zinc oxide 3.5phr, anti-aging 4020 1.5phr, anti-aging RD 0.5phr, protective wax 0.5phr, sulfur 1.0phr, accelerator (specifically sulfonamide NS and sulfonamide CZ, of which sulfonamide NS is 1.2 phr and sulfonamide CZ is 1.2 phr) 2.4phr, organic vulcanizing agent hexamethylene-1,6-bisthiosulfate disodium salt 2.0phr.

[0102] Example 4

[0103] This embodiment provides a mouth protection glue composition, the raw material components of which include:

[0104] Natural rubber 30phr, butadiene rubber 50phr, chloroprene rubber 20phr, SX72 70phr, softener (specifically aromatic oil) 3phr, stearic acid 2phr, zinc oxide 2phr, antioxidant 4020 3phr, antioxidant RD 1phr, protective wax 2.0phr, sulfur 2.0phr, accelerator (specifically sulfonamide NS) 1phr, organic vulcanizing agent hexamethylene-1,6-bisthiosulfate disodium salt 1.0phr.

[0105] Example 5

[0106] This embodiment provides a sub-mouth protection glue composition, which is different from Example 1 in that:

[0107] SX72 80phr, stearic acid 3phr, zinc oxide 3phr, accelerator 2.5phr;

[0108] The remaining components are consistent with those in Example 1.

[0109] Example 6

[0110] This embodiment provides a sub-mouth protection glue composition, which is different from Example 1 in that:

[0111] Carbon black uses N375;

[0112] The remaining components are consistent with those in Example 1.

[0113] Examples 7-12

[0114] Embodiments 7-12 provide a method for preparing a spout protective glue composition. Embodiments 7-12 respectively use the raw material formulas in Embodiments 1-6 for mixing, and include the following steps:

[0115] The first stage of master batching: add natural rubber, chloroprene rubber and 2 / 5 carbon black, press the ball for 35 seconds, remove the ball and clean it, add butadiene rubber, press the ball again and mix it, and discharge the rubber at 145℃;

[0116] The second stage of mixing: add the first stage of masterbatch and the remaining carbon black, press and mix to 120℃, add softener, protective wax, antioxidant and activator, press and mix for 30s, lift the lump for cleaning, and press and mix again to 160℃ for rubber discharge;

[0117] The third mixing stage: add the second-stage mixed rubber, inorganic vulcanizer, organic vulcanizer and accelerator, press the ball and keep it for 35 seconds, lift the ball and clean it, press the ball again and keep it for 30 seconds, lift the ball and clean it, and press the ball again to mix it to 110℃ for degumming.

[0118] Embodiment 13

[0119] This embodiment provides a method for preparing a spout protective glue composition, which uses the raw material formula in Example 2 for mixing, and includes the following steps:

[0120] The first stage of master batching: add natural rubber, chloroprene rubber and 1 / 5 carbon black, press the ball for 30 seconds, remove the ball and clean it, add butadiene rubber, press the ball again and mix it, and discharge the rubber at 140℃;

[0121] The second stage of mixing: add the first stage masterbatch and the remaining carbon black, press and mix to 115℃, add softener, protective wax, antioxidant and activator, press and mix for 35s, lift the batch for cleaning, and press and mix again to 155℃ for rubber removal;

[0122] The third mixing stage: add the second-stage mixed rubber, inorganic vulcanizer, organic vulcanizer and accelerator, press the ball for 30 seconds, lift the ball and clean it, press the ball again for 40 seconds, lift the ball and clean it, and press the ball again to mix at 105℃ to discharge the glue.

[0123] Embodiment 14

[0124] This embodiment provides a method for preparing a spout protective glue composition, which uses the raw material formula in Example 2 for mixing, and includes the following steps:

[0125] The first stage of master batching: add natural rubber, chloroprene rubber and 2 / 5 carbon black, press the ball for 40 seconds, remove the ball and clean it, add butadiene rubber, press the ball again and mix it, and discharge the rubber at 150℃;

[0126] The second stage of mixing: add the first stage masterbatch and the remaining carbon black, press and mix to 125℃, add softener, protective wax, antioxidant and activator, press and mix for 25s, lift the lump for cleaning, and press and mix again to 165℃ for debonding;

[0127] The third mixing stage: add the second-stage mixed rubber, inorganic vulcanizer, organic vulcanizer and accelerator, press the ball and keep it for 40 seconds, lift the ball and clean it, press the ball again and keep it for 35 seconds, lift the ball and clean it, and press the ball again to mix it at 115℃ to discharge the glue.

[0128] Comparative Example 1

[0129] This comparative example provides a sub-mouth protection glue composition, which is different from Example 1 in that:

[0130] Natural rubber 45phr, butadiene rubber 55phr, no chloroprene rubber added;

[0131] The remaining components are consistent with those in Example 1.

[0132] Comparative Example 2

[0133] This comparative example provides a sub-mouth protection glue composition, which is different from Example 1 in that:

[0134] Sulfur 2.0phr, no organic vulcanizing agent hexamethylene-1,6-bisthiosulfate disodium salt added;

[0135] The remaining components are consistent with those in Example 1.

[0136] Comparative Example 3

[0137] This comparative example provides a mouth protection glue composition, the raw material components of which include:

[0138] Natural rubber 40phr, butadiene rubber 60phr, N375 78phr, softener (specifically aromatic oil) 6phr, stearic acid 2phr, zinc oxide 3.5phr, antioxidant 4020 2.5phr, antioxidant RD 0.5phr, protective wax 0.5phr, sulfur 2.0phr, accelerator (specifically sulfonamide NS) 0.8phr.

[0139] Comparative Example 4

[0140] This comparative example provides a mouth protection glue composition, the raw material components of which include:

[0141] Natural rubber 40phr, butadiene rubber 60phr, SX72 78phr, softener (specifically aromatic oil) 4phr, stearic acid 2phr, zinc oxide 3.5phr, antioxidant 4020 2.5phr, antioxidant RD 0.5phr, protective wax 0.5phr, sulfur 2phr, accelerator (specifically sulfonamide NS) 1.1phr.

[0142] Comparative Examples 5-8

[0143] Comparative Examples 5-8 provide a method for preparing a sub-mouth protective glue composition. Comparative Examples 5-8 respectively use the raw material formulas in Comparative Examples 1-4 for mixing, and the mixing steps are consistent with Example 7.

[0144] Comparative Example 9

[0145] This comparative example provides a method for preparing a sub-mouth protective glue composition, which is different from Example 7 in that:

[0146] In the first masterbatch step, part of the carbon black is not added, and in the second mixing step, all the carbon black is added.

[0147] The remaining steps are consistent with Example 7.

[0148] Test Case

[0149] Test samples: The sub-mouth protection glue compositions prepared in Examples 7-14 and the sub-mouth protection glue compositions prepared in Comparative Examples 5-9 were used as samples.

[0150] Test method: The main technical indicators of the above-prepared rubber compound are shown in Table 1. The performance of the sample rubber is tested in accordance with national or industry standards, and the vulcanization condition is 151℃x30min. The tensile performance refers to GB / T528; the tearing performance refers to GB / T 529; the Akron abrasion performance refers to GB / T 1689; the flexural fatigue performance refers to GB / T13934; the tanδ test uses the dynamic viscoelastic spectrum analyzer (DMA) of the German GABO company for temperature scanning. The test results are shown in Table 1.

[0151] Table 1

[0152]

[0153] It can be seen from the data in the table that the components of comparative example 1 do not contain chloroprene rubber, and the components of comparative example 2 do not contain an organic vulcanizing agent. Compared with comparative example 1 (the data in the table corresponds to comparative example 5) and comparative example 2 (the data in the table corresponds to comparative example 6), the modulus change rate value of the sub-mouth protective rubber composition prepared in Example 7 of the present invention is lower, indicating that its modulus aging resistance is better, and its tensile product retention rate value is higher, indicating that the tensile product resistance and aging resistance performance are stronger; the carbon black in Example 12 uses N375, and Example 7 uses SX7 series carbon black. Compared with Example 12, the sub-mouth protective rubber composition prepared in Example 7 of the present invention has better modulus aging resistance and stronger tensile product resistance and aging resistance. It can be seen that in the sub-mouth protective rubber composition provided by the embodiment of the present invention, the modulus change rate of chloroprene rubber aging resistance to heat air is significantly reduced, the tensile product retention rate is significantly improved, and the comprehensive use of SX72 carbon black and an effective vulcanization system (i.e., the compound use of organic vulcanizing agent and inorganic vulcanizing agent) can significantly improve the heat aging resistance.

[0154] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A spout protection glue composition, characterized in that: The raw materials of the spigot rubber protection composition are composed of 100phr raw rubber, 70-80phr carbon black, 1.0-2.0phr inorganic vulcanizing agent, 1.0-2.0phr organic vulcanizing agent, 3.0-8.0phr softening agent, 0.5-2.0phr protective wax, 1.5-3.0phr antioxidant 4020, 0.5-1.0phr antioxidant RD, 4.0-6.0phr activator and 1-2.5phr accelerator; Wherein, the raw rubber includes 30-50 phr natural rubber, 30-50 phr butadiene rubber and 10-30 phr chloroprene rubber; the inorganic vulcanizing agent includes sulfur; the organic vulcanizing machine includes hexamethylene-1,6-bisthiosulfate disodium salt; The carbon black comprises at least one of SX71 carbon black and SX72 carbon black; The preparation method of the sub-mouth protective glue composition comprises the following steps: The natural rubber, chloroprene rubber and part of the carbon black are mixed once, and then the butadiene rubber is added for a second mixing to obtain a masterbatch, and then the masterbatch and the remaining carbon black are mixed for a third time, and then a softener, a protective wax, an antioxidant and an activator are added for a fourth mixing, and then a vulcanizer and an accelerator are added for a fifth mixing to obtain the sub-mouth protective rubber composition.

2. The spout protecting adhesive composition according to claim 1, characterized in that: The softener includes at least one of aromatic oil, tert-butyl phenolic resin and octyl phenolic resin.

3. The spout protecting adhesive composition according to claim 1, characterized in that: The antioxidant includes at least one of antioxidant 4020 and antioxidant RD.

4. The spout protecting adhesive composition according to claim 1, characterized in that: The activator includes at least one of stearic acid and zinc oxide.

5. The spout protecting adhesive composition according to claim 1, characterized in that: The accelerator includes at least one of sulfenamide NS and sulfenamide CZ.

6. The method for preparing the spout protection glue composition according to any one of claims 1 to 5, characterized in that: The following steps are involved: The natural rubber, chloroprene rubber and part of the carbon black are mixed once, and then the butadiene rubber is added for a second mixing to obtain a masterbatch, and then the masterbatch and the remaining carbon black are mixed for a third time, and then a softener, a protective wax, an antioxidant and an activator are added for a fourth mixing, and then a vulcanizer and an accelerator are added for a fifth mixing to obtain the sub-mouth protective rubber composition.

7. The preparation method according to claim 6, characterized in that: The amount of the partial carbon black added is 1 / 5-2 / 5 of the total amount of carbon black added.

8. The preparation method according to claim 6, characterized in that: The spout protecting glue composition is prepared by a mixing process.

9. The spout protecting adhesive composition according to claim 6, characterized in that: The primary mixing includes compacting and kneading, and the compacting time is 30-40s.

10. The spout protecting adhesive composition according to claim 6, characterized in that: The secondary mixing includes: adding butadiene rubber to carry out compaction and mixing, and then performing rubber removal when the temperature reaches 140-150°C.

11. The spout protecting adhesive composition according to claim 6, characterized in that: The three-stage mixing includes: mixing the masterbatch and the remaining carbon black and performing compacting and mixing.

12. The spout protecting adhesive composition according to claim 6, characterized in that: The four-time mixing includes: when the temperature of the three-time mixing reaches 115°C-125°C, adding a softener, a protective wax, an antioxidant and an activator to perform compaction and mixing for 25-35s, and performing debonding when the temperature reaches 155°C-165°C.

13. The spout protecting adhesive composition according to claim 6, characterized in that: The five mixing steps include: compacting and mixing, and performing debinding when the temperature reaches 105-115°C.

14. The spout protecting adhesive composition according to claim 6, characterized in that: The five mixings include at least two pressing and kneading, the first pressing and kneading time is 30-40s, and the second pressing and kneading time is 30-40s.

15. Use of the tire bead protection rubber composition according to any one of claims 1 to 5 or the tire bead protection rubber composition prepared by the preparation method according to any one of claims 6 to 14 in preparing a tire.

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