Low temperature resistant ethylene propylene diene rubber material and preparation method thereof

Abstract

The application relates to the technical field of rubber material preparation, in particular to a low-temperature-resistant ethylene-propylene-diene rubber material and a preparation method thereof. The low-temperature-resistant ethylene-propylene-diene rubber material according to the application comprises the following raw material components in parts by mass: ethylene-propylene-diene rubber 50-70 parts, natural rubber 15-25 parts, butyl rubber 15-25 parts, carbon black 40-50 parts, clay 5-15 parts, plasticizer 20-48 parts, stearic acid 1-3 parts, zinc oxide 3-7 parts, antioxidant 1-3 parts, vulcanizing agent 1-3 parts, accelerator 1-3 parts and dispersant 0.5-1.5 parts. The low-temperature-resistant ethylene-propylene-diene rubber material can significantly improve the flexibility of ethylene-propylene-diene rubber in a low-temperature environment, the prepared rubber can maintain good mechanical properties, and the low-temperature use performance of automobile pipelines can be effectively improved.

Description

Technical Field

[0001] This invention relates to the field of rubber materials technology, and in particular to a low-temperature resistant EPDM rubber material and its preparation method. Background Technology

[0002] The engine cooling system of commercial vehicles is a critical part of the vehicle's normal operation, and the cooling pipes are among the weakest components in the system. In low-temperature environments, if the materials used in the pipes have poor low-temperature performance, it can lead to leaks or even detachment of the pipes, reducing the coolant level in the system. In severe cases, it can even cause the engine to burn out. Therefore, there are higher requirements for the low-temperature performance of the materials used in the cooling pipes.

[0003] EPDM (ethylene propylene diene monomer) rubber is commonly used in commercial vehicle cooling pipes due to its excellent weather resistance, ozone resistance, and electrical insulation, making it widely applicable in various fields, including automotive piping. However, in certain applications, especially at low temperatures, the flexibility and mechanical properties of EPDM rubber may be affected. To improve these properties, various plasticizers, fillers, and other additives are typically added, but existing formulations still struggle to simultaneously meet the requirements for both low-temperature performance and mechanical strength. Summary of the Invention

[0004] Therefore, it is necessary to provide a low-temperature resistant EPDM rubber material and its preparation method. This application, by selecting suitable rubber matrix, fillers, plasticizers, and crosslinking systems, can significantly improve the flexibility of EPDM rubber in low-temperature environments, while maintaining good mechanical properties, effectively enhancing the low-temperature performance of automotive piping.

[0005] In a first aspect, this application provides a EPDM rubber material comprising, by weight, the following raw material components: 50-70 parts EPDM rubber, 15-25 parts natural rubber, 15-25 parts butyl rubber, 40-50 parts carbon black, 5-15 parts clay, 20-48 parts plasticizer, 1-3 parts stearic acid, 3-7 parts zinc oxide, 1-3 parts antioxidant, 1-3 parts vulcanizing agent, 1-3 parts accelerator, and 0.5-1.5 parts dispersant.

[0006] In some embodiments, the EPDM rubber satisfies at least one of the following conditions (1)-(2):

[0007] (1) The ethylene content in the EPDM rubber is 50%-55%.

[0008] (2) The content of the third monomer in the EPDM rubber is 5%-6%.

[0009] In some embodiments, the Mooney viscosity (ML1+8, 125°C) of the natural rubber is 20-40. In some embodiments, the Mooney viscosity (ML1+8, 125°C) of the butyl rubber is 40-60.

[0010] In some embodiments, the STSA specific surface area of ​​the carbon black is 70 m². 2 / g-80m 2 / g, DBP value 100-110; the filler is nano-clay.

[0011] In some embodiments, the nanoclay satisfies at least one of the following conditions (1)-(3):

[0012] (1) The nano-clay is montmorillonite that has undergone organic modification;

[0013] (2) The average particle size of the nano-clay is 4μm-8μm;

[0014] (3) The interplanar spacing of the nano-clay is 18 Å-20 Å.

[0015] In some embodiments, the plasticizer includes paraffin oil, naphthenic oil, polyester plasticizer, and ionic liquid.

[0016] In some embodiments, the mass ratio of the paraffin oil, naphthenic oil, polyester plasticizer and ionic liquid is 5-12:5-12:5-12:5-12.

[0017] In some embodiments, the antioxidant includes at least one of antioxidant 4020, antioxidant 4010NA, and antioxidant 2246; the vulcanizing agent is vulcanizing agent TMTD.

[0018] In some embodiments, the accelerator is a compound of trimethylolpropane trimethacrylate and dibenzothiazole disulfide, wherein the weight ratio of trimethylolpropane trimethacrylate to dibenzothiazole disulfide is 0.5-2:1.

[0019] A second aspect of the present invention provides a method for preparing the EPDM rubber material described in the first aspect above, the method comprising the following steps:

[0020] S1: Add EPDM rubber, natural rubber, butyl rubber, carbon black, filler, stearic acid, zinc oxide, antioxidant, and dispersant to a mixer and mix. Then add plasticizer and continue mixing until homogeneous to obtain the mixture.

[0021] S2: The mixture from step S1 is transferred to an open mill for thin-pass mixing to further homogenize it.

[0022] S3: Cool down to below 100℃, add vulcanizing agent and accelerator, mix evenly to obtain mixed rubber compound.

[0023] S4: The mixed rubber compound is calendered or extruded and vulcanized to obtain the desired product shape.

[0024] In S2, the number of thin passes is 2-3; after each thin pass, the rubber compound is cooled; in S3, the mixing time is 2-3 minutes; in S4, the vulcanization temperature is 140℃-160℃.

[0025] This application improves the flexibility and sealing properties of rubber by blending EPDM rubber, natural rubber, and butyl rubber. Simultaneously, the addition of nano-clay and plasticizers during blending allows the nano-clay's layered structure to disperse between polymer segments, increasing the intersegmental spacing. This layered structure facilitates sliding and provides lubrication, further enhancing the relative movement of the segments and improving the rubber's flexibility and low-temperature performance. The plasticizer molecules or ions, dissolved or dispersed between polymer segments, also contribute to the rubber's flexibility and low-temperature performance. The rubber material prepared in this application not only exhibits excellent low-temperature performance but also good mechanical properties, wear resistance, and excellent sealing and aging resistance. This rubber material can effectively improve the sealing reliability of cooling pipelines in low-temperature environments. Detailed Implementation

[0026] A detailed reference is now provided to embodiments of this application, one or more of which are described below. Each embodiment is provided for explanation and not for limitation. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made to this application without departing from its scope or spirit. For example, features described or illustrated as part of one embodiment may be used in another embodiment to produce further embodiments.

[0027] Therefore, this application is intended to cover such modifications and variations falling within the scope of the appended claims and their equivalents. Other objects, features, and aspects of this application are disclosed in or will be apparent from the following detailed description. It will be understood by those skilled in the art that this discussion is merely a description of exemplary embodiments and is not intended to limit the broader aspects of this application.

[0028] In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.

[0029] In this application, numerical ranges are referred to as continuous unless otherwise specified, and include the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0030] In this article, when referring to units for data ranges, if the unit is only followed by the right endpoint, it means that the units for the left and right endpoints are the same. For example, 100~150 nm means that the units for the left endpoint "100" and the right endpoint "150" are both nm (nanometers).

[0031] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0032] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0033] Unless otherwise specified, all steps in this application may be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the mention that the method may also include step (c) indicates that step (c) may be added to the method in any order; for example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0034] Unless otherwise specified, the terms "comprising" and "including" as used in this application can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0035] Unless otherwise specified, the term "or" is inclusive in this application. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, the condition "A or B" is satisfied by any of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0036] In view of the problem that traditional automotive piping materials have poor low-temperature performance and are difficult to balance low-temperature performance and mechanical strength, this application proposes a low-temperature resistant EPDM rubber material and its preparation method to solve the above-mentioned technical problems of traditional automotive, especially commercial vehicle, cooling pipe rubber materials.

[0037] In a first aspect, this application provides a EPDM rubber material comprising, by weight, the following raw material components: 50-70 parts EPDM rubber, 15-25 parts natural rubber, 15-25 parts butyl rubber, 40-50 parts carbon black, 5-15 parts clay, 20-48 parts plasticizer, 1-3 parts stearic acid, 3-7 parts zinc oxide, 1-3 parts antioxidant, 1-3 parts vulcanizing agent, 1-3 parts accelerator, and 0.5-1.5 parts dispersant.

[0038] In some embodiments of this application, the EPDM rubber material comprises, by weight, the following raw material components: 60-65 parts EPDM rubber, 15-20 parts natural rubber, 15-20 parts butyl rubber, 40-45 parts carbon black, 10-15 parts clay, 40-48 parts plasticizer, 1-3 parts stearic acid, 3-7 parts zinc oxide, 1-3 parts antioxidant, 1-3 parts vulcanizing agent, 1-3 parts accelerator, and 1-1.5 parts dispersant.

[0039] This application improves the flexibility and sealing properties of rubber by blending EPDM rubber, natural rubber, and butyl rubber. Simultaneously, the addition of nano-clay and plasticizers during blending allows the nano-clay's layered structure to disperse between polymer segments, increasing the intersegmental spacing. This layered structure facilitates sliding and provides lubrication, further enhancing the relative movement of the segments and improving the rubber's flexibility and low-temperature performance. The plasticizer molecules or ions, dissolved or dispersed between polymer segments, also contribute to the rubber's flexibility and low-temperature performance. The rubber material prepared in this application not only exhibits excellent low-temperature performance but also good mechanical properties, wear resistance, and excellent sealing and aging resistance. This rubber material can effectively improve the sealing reliability of cooling pipelines in low-temperature environments.

[0040] In some embodiments, the EPDM rubber satisfies at least one of the following conditions (1)-(2):

[0041] (1) The ethylene content in the EPDM rubber is 50%-55%, including but not limited to 50%, 51%, 52%, 53%, 54%, 55%, with 50% being preferred.

[0042] (2) The content of the third monomer in the EPDM rubber is 5%-6%, including but not limited to 5%, 5.2%, 5.4%, 5.5%, 5.8%, 6%, preferably 5.5%.

[0043] It is understood that the third monomer refers to the non-conjugated diene substances in EPDM rubber other than ethylene and propylene; the third monomer is selected from ethylene-neobornene (ENB), dicyclopentadiene (DCPD) or 1,4-hexadiene (HD); more preferably, the third monomer is ethylene-neobornene (ENB).

[0044] Preferably, the EPDM rubber is Arlanxtech's Keltan 5170.

[0045] Understandably, this application uses EPDM rubber with low ethylene content, which can increase the molecular chain side chains, increase the inter-segment spacing, improve rubber flexibility, and enhance low-temperature performance.

[0046] In some embodiments, the Mooney viscosity (ML1+8, 125°C) of natural rubber (NR) is 20-40; and the Mooney viscosity (ML1+8, 125°C) of butyl rubber (IIR) is 40-60.

[0047] Preferably, the natural rubber is STR 20. Preferably, the butyl rubber is ExxonMobil Butyl 268.

[0048] Understandably, this application improves the flexibility and sealing properties of EPDM rubber by blending natural rubber and butyl rubber with it. Specifically, it improves the low-temperature performance and increases the softness of EPDM rubber by modifying it with natural rubber; and it improves the sealing performance of EPDM rubber by modifying it with butyl rubber.

[0049] In some embodiments, the STSA specific surface area of ​​carbon black is 70 m². 2 / g-80m 2 / g, DBP value is 100-110.

[0050] Preferably, the carbon black is Corax N330.

[0051] In some implementations, the filler is nano-clay.

[0052] In some embodiments, the nanoclay satisfies at least one of the following conditions (1)-(3):

[0053] (1) The nano-clay is montmorillonite that has undergone organic modification;

[0054] (2) The average particle size of the nano-clay is 4μm-8μm;

[0055] (3) The interplanar spacing of the nano clay crystals is 18 Å-20 Å.

[0056] Preferably, the nanoclay is Cloisite 30B (Southern Chemical).

[0057] It is understandable that this application, by adding nano-clay fillers, disperses the clay nanosheet structure between polymer chain segments, increases the inter-segment spacing, and at the same time, the sheet structure is easy to slide and has a certain degree of lubrication, making the chain segments easier to move relative to each other, thereby giving the rubber better flexibility and better low-temperature performance, and can improve the flexibility and mechanical properties of EPDM rubber.

[0058] In some embodiments, the plasticizer includes paraffin oil, naphthenic oil, polyester plasticizer, and ionic liquid.

[0059] In some embodiments, the mass ratio of paraffin oil, naphthenic oil, polyester plasticizer and ionic liquid is 5-12:5-12:5-12:5-12.

[0060] In some embodiments, the proportions of paraffin oil, naphthenic oil, polyester plasticizer, and ionic liquid in the EPDM rubber material are: 5-12 parts paraffin oil, 5-12 parts naphthenic oil, 5-12 parts polyester plasticizer, and 5-12 parts ionic liquid.

[0061] In some embodiments, the EPDM rubber material, by weight, comprises the following raw material components: 50-70 parts EPDM rubber, 15-25 parts natural rubber, 15-25 parts butyl rubber, 40-50 parts carbon black, 5-15 parts clay, 5-12 parts paraffin oil, 5-12 parts naphthenic oil, 5-12 parts polyester plasticizer, 5-12 parts ionic liquid, 1-3 parts stearic acid, 3-7 parts zinc oxide, 1-3 parts antioxidant, 1-3 parts vulcanizing agent, 1-3 parts accelerator, and 0.5-1.5 parts dispersant.

[0062] Preferably, the paraffin oil is Vivatec 500 (Shell), the naphthenic oil is Nyflex 220 (NYTEX, Nynas), the polyester plasticizer is Jayflex DINP (ExxonMobil), and the ionic liquid is 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM]PF6).

[0063] Understandably, this application uses a mixture of four plasticizers to avoid the easy precipitation of a single plasticizer at low temperatures, thus increasing the amount of plasticizer that can be added. Plasticizer molecules or ions can dissolve or disperse between polymer chain segments, improving the flexibility of the rubber and enhancing the low-temperature performance of EPDM rubber.

[0064] In some embodiments, the antioxidant includes at least one of antioxidant 4020, antioxidant 4010NA, and antioxidant 2246; the vulcanizing agent is vulcanizing agent TMTD (tetramethylthiuram disulfide).

[0065] In some embodiments, the accelerator is a compound of trimethylolpropane trimethacrylate and dibenzothiazole disulfide, wherein the weight ratio of trimethylolpropane trimethacrylate to dibenzothiazole disulfide is 0.5-2:1, including but not limited to 0.5:1, 1:1, and 2:1.

[0066] Preferably, the dispersant is Clariant Licowax E.

[0067] A second aspect of the present invention provides a method for preparing the EPDM rubber material described in the first aspect above, comprising the following steps:

[0068] S1: Add EPDM rubber, natural rubber, butyl rubber, carbon black, filler, stearic acid, zinc oxide, antioxidant, and dispersant to a mixer for initial mixing. The mixing time is 9-11 minutes, preferably 10 minutes. Add plasticizer and continue mixing for about 5 minutes until the mixture is uniform and the plasticizer is evenly dispersed to obtain the mixture.

[0069] S2: The mixture from step S1 is transferred to an open mill for thin-pass mixing to further homogenize it.

[0070] S3: Cool down to below 100℃, add vulcanizing agent and accelerator, mix evenly to obtain mixed rubber compound.

[0071] S4: The mixed rubber compound is calendered or extruded and vulcanized to obtain the desired product shape.

[0072] In some embodiments, in S2, the number of thin passes is 2-3 times, including but not limited to 2 times or 3 times; the rubber compound is cooled after each thin pass.

[0073] In some embodiments, the mixing time in step S3 is 2-3 minutes, including but not limited to 2 minutes, 2.5 minutes, and 3 minutes. Mixing needs to be rapid to avoid premature cross-linking.

[0074] In S4, calendering can be carried out in a calender, and extrusion can be carried out in an extruder; the vulcanization temperature is 140℃-160℃, including but not limited to 140℃, 150℃, and 160℃.

[0075] The following are specific examples.

[0076] Example 1

[0077] A EPDM rubber material, by weight, comprises the following raw material components: 60 parts EPDM rubber, 20 parts natural rubber, 20 parts butyl rubber, 45 parts carbon black N330, 10 parts nano clay, 10 parts paraffin oil, 10 parts naphthenic oil, 10 parts polyester plasticizer, 10 parts ionic liquid, 2 parts stearic acid, 5 parts zinc oxide, 2 parts antioxidant 4020, 2 parts vulcanizing agent, 2 parts accelerator, and 1 part dispersant. The components include: EPDM rubber Keltan 5170 (Allantech); natural rubber STR 20; butyl rubber ExxonMobil Butyl 268; carbon black Corax N330; nano-clay Cloisite 30B (Southern Chemical); paraffin oil Vivatec 500 (Shell); naphthenic oil Nyflex 220 (NYTEX, Nynas); polyester plasticizer Jayflex DINP (ExxonMobil); ionic liquid [BMIM][PF6]1-butyl-3-methylimidazolium hexafluorophosphate; vulcanizing agent TMTD (tetramethylthiuram disulfide); accelerator composed of TMPT (trimethylolpropane trimethacrylate) and MBTS (dibenzothiazole disulfide) in a 1:1 weight ratio; antioxidant 4020; and dispersant Licowax E (Clariant).

[0078] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0079] S1: Internal mixer mixing: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020, and dispersant to the internal mixer for initial mixing, about 10 minutes. Add paraffin oil, naphthenic oil, polyester plasticizer, and ionic liquid, and continue mixing for about 5 minutes to ensure uniform dispersion of the plasticizer.

[0080] S2: Thin pass through open mill: Transfer the above mixture to an open mill for thin pass to further mix evenly and fully disperse the components. Perform two thin passes, allowing the rubber compound to cool for a period of time after each pass.

[0081] S3: Add vulcanizing agent: Cool to 95°C, add vulcanizing agent and accelerator, mix quickly and evenly to avoid premature cross-linking reaction. Mixing time should be controlled within 3 minutes.

[0082] S4: Molding and Vulcanization: The mixed rubber compound is pre-formed using a calender. Vulcanization is then carried out in a flat vulcanizing machine at a temperature of 150°C for 2 hours.

[0083] Example 2

[0084] A EPDM rubber material, by weight, comprises the following raw material components: 60 parts EPDM rubber, 20 parts natural rubber, 20 parts butyl rubber, 40 parts carbon black N330, 15 parts nano clay, 10 parts paraffin oil, 10 parts naphthenic oil, 10 parts polyester plasticizer, 10 parts ionic liquid, 2 parts stearic acid, 5 parts zinc oxide, 2 parts antioxidant 4020, 2 parts vulcanizing agent, 2 parts accelerator, and 1 part dispersant. The source and type of each raw material are the same as in Example 1.

[0085] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0086] (1) Internal mixer mixing: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020, and dispersant to the internal mixer for initial mixing for about 10 minutes. Add paraffin oil, naphthenic oil, polyester plasticizer, and ionic liquid, and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0087] (2) Thin pass through open mill: Transfer the above mixture to an open mill for thin pass to further mix evenly and fully disperse the components. Perform two thin passes, allowing the rubber compound to cool for a period of time after each pass.

[0088] (3) Add vulcanizing agent: Cool down to 95°C, add vulcanizing agent and accelerator, mix quickly and evenly to avoid premature cross-linking reaction. The mixing time should be controlled within 3 minutes.

[0089] (4) Molding and vulcanization: The mixed rubber compound is pre-formed by calendering. Vulcanization is carried out in a flat vulcanizing machine at a vulcanization temperature of 150℃ and a vulcanization time of 2h.

[0090] Example 3

[0091] A EPDM rubber material, by weight, comprises the following raw material components: 60 parts EPDM rubber, 20 parts natural rubber, 20 parts butyl rubber, 45 parts carbon black N330, 10 parts nano clay, 12 parts paraffin oil, 12 parts naphthenic oil, 12 parts polyester plasticizer, 12 parts ionic liquid, 2 parts stearic acid, 5 parts zinc oxide, 2 parts antioxidant 4020, 2 parts vulcanizing agent, 2 parts accelerator, and 1 part dispersant. The source and type of each raw material are the same as in Example 1.

[0092] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0093] (1) Internal mixer mixing: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020, and dispersant to the internal mixer for initial mixing for about 10 minutes. Add paraffin oil, naphthenic oil, polyester plasticizer, and ionic liquid, and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0094] (2) Thin pass through open mill: Transfer the above mixture to an open mill for thin pass to further mix evenly and fully disperse the components. Perform two thin passes, allowing the rubber compound to cool for a period of time after each pass.

[0095] (3) Add vulcanizing agent: Cool down to 95°C, add vulcanizing agent and accelerator, mix quickly and evenly to avoid premature cross-linking reaction. The mixing time should be controlled within 3 minutes.

[0096] (4) Molding and vulcanization: The mixed rubber compound is pre-formed by calendering. Vulcanization is carried out in a flat vulcanizing machine at a vulcanization temperature of 150℃ and a vulcanization time of 2h.

[0097] Example 4

[0098] A EPDM rubber material, by weight, comprises the following raw material components: 65 parts EPDM rubber, 20 parts natural rubber, 15 parts butyl rubber, 45 parts carbon black N330, 10 parts nano clay, 10 parts paraffin oil, 10 parts naphthenic oil, 10 parts polyester plasticizer, 10 parts ionic liquid, 2 parts stearic acid, 5 parts zinc oxide, 2 parts antioxidant 4020, 2 parts vulcanizing agent, 2 parts accelerator, and 1 part dispersant. The source and type of each raw material are the same as in Example 1.

[0099] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0100] (1) Internal mixer mixing: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020, and dispersant to the internal mixer for initial mixing for about 10 minutes. Add paraffin oil, naphthenic oil, polyester plasticizer, and ionic liquid, and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0101] (2) Thin pass through open mill: Transfer the above mixture to an open mill for thin pass to further mix evenly and fully disperse the components. Perform two thin passes, allowing the rubber compound to cool for a period of time after each pass.

[0102] (3) Add vulcanizing agent: Cool down to 95°C, add vulcanizing agent and accelerator, mix quickly and evenly to avoid premature cross-linking reaction. The mixing time should be controlled within 3 minutes.

[0103] (4) Molding and vulcanization: The mixed rubber compound is pre-formed by calendering. Vulcanization is carried out in a flat vulcanizing machine at a vulcanization temperature of 150℃ and a vulcanization time of 2h.

[0104] Example 5

[0105] A EPDM rubber material, by weight, comprises the following raw material components: 65 parts EPDM rubber, 15 parts natural rubber, 20 parts butyl rubber, 45 parts carbon black N330, 10 parts nano clay, 10 parts paraffin oil, 10 parts naphthenic oil, 10 parts polyester plasticizer, 10 parts ionic liquid, 2 parts stearic acid, 5 parts zinc oxide, 2 parts antioxidant 4020, 2 parts vulcanizing agent, 2 parts accelerator, and 1 part dispersant. The source and type of each raw material are the same as in Example 1.

[0106] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0107] (1) Internal mixer mixing: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020, and dispersant to the internal mixer for initial mixing for about 10 minutes. Add paraffin oil, naphthenic oil, polyester plasticizer, and ionic liquid, and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0108] (2) Thin pass through open mill: Transfer the above mixture to an open mill for thin pass to further mix evenly and fully disperse the components. Perform two thin passes, allowing the rubber compound to cool for a period of time after each pass.

[0109] (3) Add vulcanizing agent: Cool down to 95°C, add vulcanizing agent and accelerator, mix quickly and evenly to avoid premature cross-linking reaction. The mixing time should be controlled within 3 minutes.

[0110] (4) Molding and vulcanization: The mixed rubber compound is pre-formed by calendering. Vulcanization is carried out in a flat vulcanizing machine at a vulcanization temperature of 150℃ and a vulcanization time of 2h.

[0111] Example 6

[0112] A EPDM rubber material, by weight, comprises the following raw material components: 50 parts EPDM rubber, 15 parts natural rubber, 15 parts butyl rubber, 45 parts carbon black N330, 5 parts nano clay, 5 parts paraffin oil, 5 parts naphthenic oil, 5 parts polyester plasticizer, 5 parts ionic liquid, 1 part stearic acid, 3 parts zinc oxide, 1 part antioxidant 4020, 1 part vulcanizing agent, 1 part accelerator, and 0.5 parts dispersant. The source and type of each raw material are the same as in Example 1.

[0113] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0114] S1: Internal mixer mixing: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020, and dispersant to the internal mixer for initial mixing, approximately 9 minutes. Add paraffin oil, naphthenic oil, polyester plasticizer, and ionic liquid, and continue mixing for approximately 5 minutes to ensure uniform dispersion of the plasticizer.

[0115] S2: Thin pass through open mill: Transfer the above mixture to an open mill for thin pass to further mix evenly and fully disperse the components. Perform thin pass 3 times, allowing the rubber compound to cool for a period of time after each pass.

[0116] S3: Add vulcanizing agent: Cool to 95°C, add vulcanizing agent and accelerator, mix quickly and evenly to avoid premature cross-linking reaction. Mixing time should be controlled within 3 minutes.

[0117] S4: Molding and Vulcanization: The mixed rubber compound is pre-formed using a calender. Vulcanization is then carried out in a flat vulcanizing machine at a temperature of 140℃ for 2 hours.

[0118] Example 7

[0119] A EPDM rubber material, by weight, comprises the following raw material components: 70 parts EPDM rubber, 20 parts natural rubber, 20 parts butyl rubber, 50 parts carbon black N330, 10 parts nano clay, 10 parts paraffin oil, 10 parts naphthenic oil, 10 parts polyester plasticizer, 10 parts ionic liquid, 3 parts stearic acid, 7 parts zinc oxide, 3 parts antioxidant 4020, 3 parts vulcanizing agent, 3 parts accelerator, and 1.5 parts dispersant. The source and type of each raw material are the same as in Example 1.

[0120] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0121] S1: Internal mixer mixing: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020, and dispersant to the internal mixer for initial mixing, approximately 11 minutes. Add paraffin oil, naphthenic oil, polyester plasticizer, and ionic liquid, and continue mixing for approximately 5 minutes to ensure uniform dispersion of the plasticizer.

[0122] S2: Thin pass through open mill: Transfer the above mixture to an open mill for thin pass to further mix evenly and fully disperse the components. Perform two thin passes, allowing the rubber compound to cool for a period of time after each pass.

[0123] S3: Add vulcanizing agent: Cool to 95°C, add vulcanizing agent and accelerator, mix quickly and evenly to avoid premature cross-linking reaction. Mixing time should be controlled within 2 minutes.

[0124] S4: Molding and Vulcanization: The mixed rubber compound is pre-formed using a calender. Vulcanization is then carried out in a flat vulcanizing machine at a temperature of 160℃ for 2 hours.

[0125] Comparative Example 1

[0126] A EPDM rubber material, by weight, comprises the following raw material components: 100 parts EPDM rubber, 45 parts carbon black N330, 10 parts nano clay, 10 parts paraffin oil, 10 parts naphthenic oil, 10 parts polyester plasticizer, 10 parts ionic liquid, 2 parts stearic acid, 5 parts zinc oxide, 2 parts antioxidant 4020, 2 parts vulcanizing agent, 2 parts accelerator, and 1 part dispersant. The source and type of each raw material are the same as in Example 1.

[0127] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0128] (1) Internal mixer mixing: Add EPDM rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020 and dispersant to the internal mixer for initial mixing, and mix for about 10 minutes. Add paraffin oil, naphthenic oil, polyester plasticizer and ionic liquid, and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0129] (2) Thin pass through open mill: Transfer the above mixture to an open mill for thin pass to further mix evenly and fully disperse the components. Perform two thin passes, allowing the rubber compound to cool for a period of time after each pass.

[0130] (3) Add vulcanizing agent: Cool down to 95°C, add vulcanizing agent and accelerator, mix quickly and evenly to avoid premature cross-linking reaction. The mixing time should be controlled within 3 minutes.

[0131] (4) Molding and vulcanization: The mixed rubber compound is pre-formed by calendering. Vulcanization is carried out in a flat vulcanizing machine at a vulcanization temperature of 150℃ and a vulcanization time of 2h.

[0132] Comparative Example 2

[0133] A EPDM rubber material, by weight, comprises the following raw material components: 60 parts EPDM rubber, 20 parts natural rubber, 20 parts butyl rubber, 55 parts carbon black N330, 10 parts paraffin oil, 10 parts naphthenic oil, 10 parts polyester plasticizer, 10 parts ionic liquid, 2 parts stearic acid, 5 parts zinc oxide, 2 parts antioxidant 4020, 2 parts vulcanizing agent, 2 parts accelerator, and 1 part dispersant. The source and type of each raw material are the same as in Example 1.

[0134] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0135] (1) Internal mixer mixing: Add EPDM rubber, natural rubber, butyl rubber, carbon black, stearic acid, zinc oxide, antioxidant 4020 and dispersant to the internal mixer for initial mixing, and mix for about 10 minutes. Add paraffin oil, naphthenic oil, polyester plasticizer and ionic liquid, and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0136] (2) Thin pass through open mill: Transfer the above mixture to an open mill for thin pass to further mix evenly and fully disperse the components. Perform two thin passes, allowing the rubber compound to cool for a period of time after each pass.

[0137] (3) Add vulcanizing agent: Cool down to 95°C, add vulcanizing agent and accelerator, mix quickly and evenly to avoid premature cross-linking reaction. The mixing time should be controlled within 3 minutes.

[0138] (4) Molding and vulcanization: The mixed rubber compound is pre-formed by calendering. Vulcanization is carried out in a flat vulcanizing machine at a vulcanization temperature of 150℃ and a vulcanization time of 2h.

[0139] Comparative Example 3

[0140] A EPDM rubber material, by weight, comprises the following raw material components: 60 parts EPDM rubber, 20 parts natural rubber, 20 parts butyl rubber, 45 parts carbon black N330, 10 parts nano clay, 40 parts paraffin oil, 2 parts stearic acid, 5 parts zinc oxide, 2 parts antioxidant 4020, 2 parts vulcanizing agent, 2 parts accelerator, and 1 part dispersant. The source and type of each raw material are the same as in Example 1.

[0141] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0142] (1) Internal mixer mixing: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020, and dispersant to the internal mixer for initial mixing for about 10 minutes. Add paraffin oil, naphthenic oil, polyester plasticizer, and ionic liquid, and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0143] (2) Thin pass through open mill: Transfer the above mixture to an open mill for thin pass to further mix evenly and fully disperse the components. Perform two thin passes, allowing the rubber compound to cool for a period of time after each pass.

[0144] (3) Add vulcanizing agent: Cool down to 95°C, add vulcanizing agent and accelerator, mix quickly and evenly to avoid premature cross-linking reaction. The mixing time should be controlled within 3 minutes.

[0145] (4) Molding and vulcanization: The mixed rubber compound is pre-formed by calendering. Vulcanization is carried out in a flat vulcanizing machine at a vulcanization temperature of 150℃ and a vulcanization time of 2h.

[0146] Comparative Example 4

[0147] A EPDM rubber material is provided, with raw materials and proportions basically the same as in Example 1, except that butyl rubber is not added, and natural rubber is used in 40 parts. The preparation method of the above EPDM rubber material is the same as in Example 1.

[0148] Comparative Example 5

[0149] A EPDM rubber material is provided, with raw materials and proportions basically the same as in Example 1, except that natural rubber is not added and 40 parts of butyl rubber are used. The preparation method of the above EPDM rubber material is the same as in Example 1.

[0150] Comparative Example 6

[0151] A EPDM rubber material is provided, with raw materials and proportions basically the same as in Example 1, except that nano-clay is replaced with ordinary clay. The preparation method of the above EPDM rubber material is the same as in Example 1.

[0152] Comparative Example 7

[0153] A EPDM rubber material is provided, with raw materials and proportions basically the same as in Example 1, except that only 20 parts of polyester plasticizer and 20 parts of paraffin oil are added. The preparation method of the above EPDM rubber material is the same as in Example 1.

[0154] Test example:

[0155] The EPDM rubber materials prepared in Examples 1-5 and Comparative Examples 1-7 were subjected to performance tests, and the test results are shown in the table below.

[0156] Table 1 Performance tests of the examples and comparative examples

[0157]

[0158] As shown in the table above, comparing Example 1 with Comparative Example 1, it is evident that when only EPDM rubber is used, the Shore A hardness of the prepared EPDM rubber material increases significantly, resulting in poor low-temperature performance. Comparing Examples 1 and 4 with Comparative Example 4, it is clear that reducing the butyl rubber ratio decreases its mechanical properties. Comparing Examples 1 and 5 with Comparative Example 5, it is clear that reducing the natural rubber ratio decreases its low-temperature performance. Comparing Examples 1 and Comparative Examples 2 and 6, it is clear that without the addition of nano-clay, its low-temperature performance deteriorates, and its Shore A hardness increases. Comparing Examples 1 and Comparative Examples 3 and 7, it is clear that using only petroleum wax or two plasticizers reduces tensile strength, elongation at break, and tear strength, while also resulting in poor low-temperature performance.

[0159] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0160] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A low-temperature resistant EPDM rubber material, characterized in that, By mass, it includes the following raw material components: 50-70 parts EPDM rubber, 15-25 parts natural rubber, 15-25 parts butyl rubber, 40-50 parts carbon black, 5-15 parts nano clay, 20-48 parts plasticizer; 1-3 parts stearic acid, 3-7 parts zinc oxide, 1-3 parts antioxidant, 1-3 parts vulcanizing agent, 1-3 parts accelerator, and 0.5-1.5 parts dispersant. The ethylene content in the EPDM rubber is 50%-55%; The nanoclay is Cloisite 30B; The plasticizers include paraffin oil, naphthenic oil, polyester plasticizers, and ionic liquids; The mass ratio of paraffin oil, naphthenic oil, polyester plasticizer and ionic liquid is 5-12:5-12:5-12:5-12.

2. The low-temperature resistant EPDM rubber material according to claim 1, characterized in that, The content of the third monomer in the EPDM rubber is 5%-6%.

3. The low-temperature resistant EPDM rubber material according to claim 1, characterized in that, The Mooney viscosity (ML1+8, 125°C) of the natural rubber is 20-40.

4. The EPDM rubber material according to claim 1, characterized in that, The Mooney viscosity (ML1+8, 125℃) of the butyl rubber is 40-60.

5. The low-temperature resistant EPDM rubber material according to claim 1, characterized in that, The STSA specific surface area of ​​the carbon black is 70 m². 2 / g-80m 2 / g, DBP value is 100-110.

6. The low-temperature resistant EPDM rubber material according to claim 1, characterized in that, The antioxidant includes at least one of antioxidant 4020, antioxidant 4010NA, and antioxidant 2246; The vulcanizing agent is vulcanizing agent TMTD; The accelerator is a compound of trimethylolpropane trimethacrylate and dibenzothiazole disulfide, wherein the weight ratio of trimethylolpropane trimethacrylate to dibenzothiazole disulfide is 0.5-2:

1.

7. A method for preparing a low-temperature resistant EPDM rubber material according to any one of claims 1-6, characterized in that, The preparation method includes the following steps: S1: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant, and dispersant to a mixer and mix. Then add plasticizer and continue mixing until homogeneous to obtain a mixture. S2: The mixture from step S1 is transferred to a two-roll mill for thin-pass mixing to further homogenize it; S3: Cool down to below 100℃, add vulcanizing agent and accelerator, mix evenly to obtain mixed rubber compound; S4: The mixed rubber compound is vulcanized by calendering or extrusion to obtain the desired product shape; In S2, the thin pass is performed 2-3 times; the rubber compound is cooled after each thin pass; in S3, the mixing time is 2-3 minutes; in S4, the vulcanization temperature is 140℃-160℃. The ethylene content in the EPDM rubber is 50%-55%; The nanoclay is Cloisite 30B; The plasticizers include paraffin oil, naphthenic oil, polyester plasticizers, and ionic liquids; The mass ratio of paraffin oil, naphthenic oil, polyester plasticizer and ionic liquid is 5-12:5-12:5-12:5-12.

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