A ternary ethylene-propylene rubber composition containing a high flash point paraffin oil and a method for preparing the same
Patent Information
- Application Number
- CN202611275683.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-08-21
- Publication Date
- 2026-10-27
AI Technical Summary
[0007]本发明公开一种含有高闪点石蜡油的三元乙丙橡胶组合物及其制备方法，所述改性蒙脱土采用KH560、氨基POSS、端环氧基聚丁二烯反应改性制得，能够有效改善蒙脱土在橡胶基体中的分散性与界面相容性，构建多层致密隔热阻隔网络，大幅降低复合材料导热系数；搭配高闪点石蜡油协同作用，可稳定填充基体间隙、强化界面结合，显著提升橡胶组合物的热稳定性与隔热性能，可有效解决传统EPDM橡胶隔热性差、高温易失效、性能不均的问题，适用于各类高温隔热、密封防护工况，应用前景广阔
首先，利用KH560对蒙脱土进行改性，再与氨基POSS进行反应，最后与端环氧基聚丁二烯进行反应，在蒙脱土表面接枝柔性高分子链段，实现无机填料与有机橡胶基体的分子级相容，显著改善蒙脱土在橡胶基体中的分散性与界面结合力。柔性聚丁二烯接枝链与三元乙丙橡胶具有良好结构相似性与相容性，可有效降低蒙脱土片层间的聚集倾向，实现均匀分散，并在橡胶内构筑出致密的物理交联网络和热屏障层，有效延长热量传递路径并降低热导率，从而赋予组合物突出的隔热性能。
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Abstract
Description
Technical Field
[0001] This invention relates to the field of EPDM rubber technology, and in particular to an EPDM rubber composition containing high flash point paraffin oil and its preparation method. Background Technology
[0002] Ethylene propylene diene monomer (EPDM) rubber possesses excellent weather resistance, ozone resistance, low-temperature resistance, and electrical insulation properties, making it widely used in automotive sealing products, hoses, cable protection, and building sealing. Paraffin oil is the most commonly used softening and plasticizing agent for EPDM rubber, effectively improving the rubber's processing fluidity, enhancing the compound's softness and molding appearance, and reducing energy consumption during mixing and extrusion. It is an indispensable key component in EPDM rubber formulations.
[0003] Currently, conventional EPDM rubber systems generally use ordinary paraffin oil combined with conventional inorganic fillers to prepare rubber composites. However, this type of system has obvious technical defects: ordinary paraffin oil has a low flash point and a high content of small molecule components. Under high temperature processing and long-term high temperature service conditions, it is prone to migration, seepage and thermal volatilization, resulting in oil seepage on the surface of rubber products, decreased dimensional stability and serious degradation of mechanical properties. At the same time, volatile components are prone to generating VOCs, resulting in poor heat resistance and long-term service stability.
[0004] Montmorillonite, as a typical two-dimensional layered nanofiller, effectively inhibits the migration and diffusion of small-molecule additives in polymer matrices due to its unique lamellar labyrinth barrier effect. It is often used to modify rubber materials to improve their barrier and heat resistance properties. Current technologies mostly employ a single silane coupling agent to directly modify montmorillonite, or simply blend montmorillonite with the rubber matrix. These methods are limited in scope and have limited lamellar exfoliation effects. Furthermore, the filler and rubber matrix have poor interfacial compatibility, making agglomeration and stacking highly likely. This not only fails to fully utilize the barrier advantages of montmorillonite but also degrades the processing performance and mechanical stability of the rubber compound.
[0005] Furthermore, the existing modified montmorillonite has a relatively simple modified structure, relying solely on inorganic lamellar physical barriers and lacking an organic-inorganic covalent hybrid network structure. This results in an inability to form a stable composite thermal insulation barrier layer under high-temperature conditions, poor long-term inhibition of paraffin oil volatilization and migration, and insufficient high-temperature ablation performance and thermal stability to meet the requirements of high-end heat-resistant rubber products. Simultaneously, the conventional formulations often have a crude combination of zinc oxide and additives, resulting in poor filler dispersibility, further limiting the overall performance improvement of EPDM rubber compositions.
[0006] In summary, existing EPDM rubber compositions generally suffer from technical shortcomings such as easy migration and volatilization of paraffin oil, poor high-temperature thermal stability, uneven filler dispersion, insufficient barrier and heat insulation performance, and poor long-term service stability, making them unsuitable for industrial applications requiring high temperature, high safety, and long service life. Summary of the Invention
[0007] This invention discloses a EPDM rubber composition containing high flash point paraffin oil and its preparation method. The modified montmorillonite is prepared by reaction modification with KH560, amino POSS, and terminal epoxy polybutadiene, which can effectively improve the dispersibility and interfacial compatibility of montmorillonite in the rubber matrix, construct a multi-layer dense thermal insulation barrier network, and significantly reduce the thermal conductivity of the composite material. Combined with the synergistic effect of high flash point paraffin oil, it can stably fill the matrix gaps, strengthen the interfacial bonding, and significantly improve the thermal stability and thermal insulation performance of the rubber composition. It can effectively solve the problems of poor thermal insulation, easy failure at high temperatures, and uneven performance of traditional EPDM rubber, and is suitable for various high-temperature thermal insulation and sealing protection conditions, with broad application prospects.
[0008] Therefore, it is necessary to provide a EPDM rubber composition containing high flash point paraffin oil, comprising the following components in parts by weight: 70-100 parts of EPDM rubber 12-15 parts of modified montmorillonite 15-25 parts paraffin oil 1-5 parts zinc oxide 1-2 parts stearic acid 5-20 parts of auxiliary agent; The modified montmorillonite is obtained by reacting KH560 modified montmorillonite with amino POSS, and then reacting it with terminal epoxy polybutadiene.
[0009] Furthermore, the flash point of the paraffin oil is ≥290℃.
[0010] Furthermore, the zinc oxide has a particle size of 0.3-2 μm.
[0011] Furthermore, the additive is selected from one or more of the following: accelerator, antioxidant, vulcanizing agent, vulcanizing agent, and foaming agent.
[0012] Furthermore, the vulcanizing agent is selected from one or more of di-tert-butyl peroxide, dicumyl peroxide, and sulfur.
[0013] The present invention also provides a method for preparing the EPDM rubber composition containing high flash point paraffin oil, comprising the following steps: S1. Under the protection of an inert gas, montmorillonite and KH560 are mixed and heated to react, yielding KH560 modified montmorillonite; S2. Mix amino POSS and KH560 modified montmorillonite, heat and react to obtain intermediate product; S3. Mix terminal epoxy-terminated polybutadiene with the intermediate product and heat to react, to obtain modified montmorillonite; S4. Modified montmorillonite is blended with other components to obtain a EPDM rubber composition containing high flash point paraffin oil.
[0014] Furthermore, in step S1, the heating temperature is 65-70°C.
[0015] Furthermore, in step S2, the heating temperature is 95-100℃.
[0016] Furthermore, in step S3, the heating temperature is 90-95℃.
[0017] The present invention has the following beneficial effects: First, montmorillonite was modified using KH560, then reacted with amino POSS, and finally reacted with terminal epoxy-terminated polybutadiene to graft flexible polymer chains onto the surface of the montmorillonite. This achieved molecular-level compatibility between the inorganic filler and the organic rubber matrix, significantly improving the dispersibility and interfacial bonding of montmorillonite in the rubber matrix. The flexible polybutadiene grafted chains have good structural similarity and compatibility with EPDM rubber, effectively reducing the aggregation tendency between montmorillonite layers, achieving uniform dispersion, and constructing a dense physical cross-linked network and thermal barrier layer within the rubber. This effectively extends the heat transfer path and reduces thermal conductivity, thereby endowing the composition with outstanding thermal insulation properties.
[0018] Meanwhile, the highly thermally stable amino POSS and terminal epoxy-terminated polybutadiene segments synergistically enhance the interfacial bonding between montmorillonite and the rubber matrix, improving the ability to maintain the layered structure at high temperatures and preventing the thermal insulation performance from deteriorating with increasing temperature. Simultaneously, the rigid cage-like structure of POSS provides physical steric hindrance, further preventing layer stacking.
[0019] Furthermore, the high flash point (≥290℃) paraffin oil and modified montmorillonite form a synergistic effect. The paraffin oil fills the gaps between the modified montmorillonite layers and the free volume of the rubber. It is not easy to volatilize or migrate at high temperatures, maintaining the dense and uniform structure inside the composition. This further enhances the heat insulation durability and heat aging resistance, effectively solving the problems of high thermal conductivity and rapid heat insulation decay of conventional EPDM rubber at high temperatures. It is suitable for sealing, protection and other applications with stringent requirements for heat insulation and heat resistance. Detailed Implementation
[0020] To more clearly illustrate the technical solution of the present invention, the following embodiments are provided. Unless otherwise stated, the raw materials, reactions, and post-processing methods appearing in the embodiments are all commercially available raw materials and technical methods well known to those skilled in the art.
[0021] The terms "preferred," "more preferably," and "more suitable" used in this invention refer to embodiments of the invention that provide certain beneficial effects under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the description of one or more preferred embodiments does not imply that other embodiments are unavailable, nor is it intended to exclude other embodiments from the scope of this invention.
[0022] It should be understood that, except in any operational instance or otherwise indicated, all figures representing the amounts of ingredients used, for example, in the specification and claims, should be understood to be modified in all cases by the term "about". Therefore, unless otherwise stated, the numerical parameters set forth in the following specification and appended claims are approximations varying with the desired performance to be obtained according to the invention.
[0023] EPDM rubber: Dow Chemical 774P.
[0024] Paraffin oil: Oujia 2280, purchased from Hebei Oujia Lubricating Oil Co., Ltd.
[0025] Epoxy-terminated polybutadiene: purchased from Tianyuan Aviation Materials.
[0026] The accelerator is a mixture of accelerator M and accelerator TMTD in a mass ratio of 2:1.
[0027] Antioxidant: Antioxidant RD.
[0028] Vulcanizing agent: sulfur.
[0029] Foaming agent: OBSH.
[0030] AminoPOSS: Octamonylated cage-like silsesquioxane, 342313, purchased from Xi'an Qiyue Biotechnology Co., Ltd. Example 1
[0031] A EPDM rubber composition containing high flash point paraffin oil comprises the following components in parts by weight: 77 parts of ethylene propylene diene monomer (EPDM) rubber 12 parts of modified montmorillonite 17.5 parts paraffin oil 3 parts zinc oxide 1 part of accelerator Anti-aging agent 1.5 parts 1.5 parts vulcanizing agent 5 parts foaming agent 1 part stearic acid; The preparation method of the above-mentioned EPDM rubber composition containing high flash point paraffin oil includes the following steps: S1. Under nitrogen protection, using a mixture of ethanol and water in a volume ratio of 5:1 as a solvent, montmorillonite and KH560 were mixed, heated to 75°C and reacted for 24 hours. The mixture was then filtered, washed, and dried to obtain KH560 modified montmorillonite. The mass ratio of montmorillonite to KH560 is 3:0.5; S2. Using toluene as solvent, aminoPOSS and KH560 modified montmorillonite were mixed, heated to reflux and stirred for 4 hours, filtered, washed, and dried to obtain the intermediate product; The mass ratio of aminoPOSS to KH560 modified montmorillonite is 1:10; S3. Using toluene as a solvent, the terminal epoxy polybutadiene was mixed with the intermediate product, heated to 95°C and stirred for 10 h, filtered, washed and dried to obtain modified montmorillonite; The mass ratio of the terminal epoxy polybutadiene to the intermediate product is 0.5:4; S4. According to the above-mentioned mass proportions, EPDM rubber and other components (excluding accelerator, vulcanizing agent and foaming agent) are mixed, and the mixture is kneaded at 100°C for 10 minutes. After cooling to 70°C, the remaining components are added and the mixture is kneaded for another 5 minutes. The mixture is then discharged to obtain a compound. The compound is then added to a mold and vulcanized and foamed at 155°C for 25 minutes to obtain an EPDM rubber composition containing high flash point paraffin oil. Example 2
[0032] A EPDM rubber composition containing high flash point paraffin oil comprises the following components in parts by weight: 85 parts of EPDM rubber 14 parts of modified montmorillonite 22 parts paraffin oil 4 parts zinc oxide 1 part of accelerator Anti-aging agent 1.5 parts 1.5 parts vulcanizing agent 5 parts foaming agent 1 part stearic acid; The preparation method of the above-mentioned EPDM rubber composition containing high flash point paraffin oil includes the following steps: S1. Under nitrogen protection, using a mixture of ethanol and water in a volume ratio of 5:1 as a solvent, montmorillonite and KH560 were mixed, heated to 75°C and reacted for 24 hours. The mixture was then filtered, washed, and dried to obtain KH560 modified montmorillonite. The mass ratio of montmorillonite to KH560 is 3:0.5; S2. Using toluene as solvent, aminoPOSS and KH560 modified montmorillonite were mixed, heated to reflux and stirred for 4 hours, filtered, washed, and dried to obtain the intermediate product; The mass ratio of aminoPOSS to KH560 modified montmorillonite is 1:10; S3. Using toluene as a solvent, the terminal epoxy polybutadiene was mixed with the intermediate product, heated to 95°C and stirred for 10 h, filtered, washed and dried to obtain modified montmorillonite; The mass ratio of the terminal epoxy polybutadiene to the intermediate product is 0.5:4; S4. According to the above-mentioned mass proportions, EPDM rubber and other components (excluding accelerator, vulcanizing agent and foaming agent) are mixed, and the mixture is kneaded at 100°C for 10 minutes. After cooling to 70°C, the remaining components are added and the mixture is kneaded for another 5 minutes. The mixture is then discharged to obtain a compound. The compound is then added to a mold and vulcanized and foamed at 155°C for 25 minutes to obtain an EPDM rubber composition containing high flash point paraffin oil. Example 3
[0033] A EPDM rubber composition containing high flash point paraffin oil comprises the following components in parts by weight: 92 parts of ethylene propylene diene monomer (EPDM) rubber 15 parts of modified montmorillonite 23 parts paraffin oil 5 parts zinc oxide 1 part of accelerator Anti-aging agent 1.5 parts 1.5 parts vulcanizing agent 5 parts foaming agent 1 part stearic acid; The preparation method of the above-mentioned EPDM rubber composition containing high flash point paraffin oil includes the following steps: S1. Under nitrogen protection, using a mixture of ethanol and water in a volume ratio of 5:1 as a solvent, montmorillonite and KH560 were mixed, heated to 75°C and reacted for 24 hours. The mixture was then filtered, washed, and dried to obtain KH560 modified montmorillonite. The mass ratio of montmorillonite to KH560 is 3:0.5; S2. Using toluene as solvent, aminoPOSS and KH560 modified montmorillonite were mixed, heated to reflux and stirred for 4 hours, filtered, washed, and dried to obtain the intermediate product; The mass ratio of aminoPOSS to KH560 modified montmorillonite is 1:10; S3. Using toluene as a solvent, the terminal epoxy polybutadiene was mixed with the intermediate product, heated to 95°C and stirred for 10 h, filtered, washed and dried to obtain modified montmorillonite; The mass ratio of the terminal epoxy polybutadiene to the intermediate product is 0.5:4; S4. According to the above-mentioned mass proportions, EPDM rubber and other components (excluding accelerator, vulcanizing agent and foaming agent) are mixed, and the mixture is kneaded at 100°C for 10 minutes. After cooling to 70°C, the remaining components are added and the mixture is kneaded for another 5 minutes. The mixture is then discharged to obtain a compound. The compound is then added to a mold and vulcanized and foamed at 155°C for 25 minutes to obtain an EPDM rubber composition containing high flash point paraffin oil. Comparative Example 1
[0034] A terephthalic acid propylene diene monomer (EPDM) rubber composition containing high flash point paraffin oil. The difference between this comparative example and Example 1 is that step S3 is removed, and an intermediate product is used to replace an equal mass of modified montmorillonite. Other components and preparation methods are the same. Comparative Example 2
[0035] A terephthalic acid propylene diene monomer (EPDM) rubber composition containing high flash point paraffin oil. The difference between this comparative example and Example 1 is that steps S2 and S3 are removed, and KH560 modified montmorillonite is used to replace an equal mass of modified montmorillonite. Other components and preparation methods are the same. Test case
[0036] The performance of the EPDM rubber compositions containing high flash point paraffin oil prepared in Example 1 and Comparative Examples 1-2 was tested.
[0037] Tensile strength and elongation at break: According to GB / T 528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber", prepare dumbbell-shaped test specimens, stretch them at a speed of 500 mm / min, and record the test results.
[0038] Thermal conductivity: According to GB / T 11205-2022 "Determination of thermal conductivity of rubber by hot wire method", a heating wire (hot wire) is embedded in the rubber sample. After the power is turned on, the temperature of the hot wire increases with time, and the temperature-time curve is recorded. The thermal conductivity is calculated by the slope of the curve.
[0039] Thermal aging performance test: The sample is placed in a hot air aging test chamber at 70℃ and left under normal pressure for 72 hours, and then its tensile strength and elongation at break are tested.
[0040] The results are shown in Table 1.
[0041] Table 1 Performance Test Results
[0042] According to Table 1, the EPDM rubber composition containing high flash point paraffin oil prepared in Example 1 has the best overall performance, with good mechanical properties, heat insulation effect and aging resistance.
[0043] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.
[0044] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.
Claims
1. A EPDM rubber composition containing high flash point paraffin oil, characterized in that, The components include the following parts by mass: 70-100 parts of EPDM rubber 12-15 parts of modified montmorillonite 15-25 parts paraffin oil 1-5 parts zinc oxide 1-2 parts stearic acid 5-20 parts of auxiliary agent; The modified montmorillonite is obtained by reacting KH560 modified montmorillonite with amino POSS, and then reacting it with terminal epoxy polybutadiene.
2. The EPDM rubber composition containing high flash point paraffin oil according to claim 1, characterized in that, The flash point of the paraffin oil is ≥290℃.
3. The EPDM rubber composition containing high flash point paraffin oil according to claim 1, characterized in that, The zinc oxide has a particle size of 0.3-2 μm.
4. The EPDM rubber composition containing high flash point paraffin oil according to claim 1, characterized in that, The additives are selected from one or more of plasticizers, accelerators, antioxidants, vulcanizing agents, vulcanizing aids, and foaming agents.
5. The EPDM rubber composition containing high flash point paraffin oil according to claim 1, characterized in that, The vulcanizing agent is selected from one or more of di-tert-butyl peroxide, dicumyl peroxide, and sulfur.
6. A method for preparing the EPDM rubber composition containing high flash point paraffin oil according to any one of claims 1-5, characterized in that, Includes the following steps: S1. Under the protection of an inert gas, montmorillonite and KH560 are mixed and heated to react, yielding KH560 modified montmorillonite; S2. Mix amino POSS and KH560 modified montmorillonite, heat and react to obtain intermediate product; S3. Mix terminal epoxy-terminated polybutadiene with the intermediate product and heat to react, to obtain modified montmorillonite; S4. Modified montmorillonite is blended with other components to obtain a EPDM rubber composition containing high flash point paraffin oil.
7. The method for preparing the EPDM rubber composition containing high flash point paraffin oil according to claim 6, characterized in that, In step S1, the heating temperature is 65-70℃.
8. The method for preparing the EPDM rubber composition containing high flash point paraffin oil according to claim 6, characterized in that, In step S2, the heating temperature is 95-100℃.
9. The method for preparing the EPDM rubber composition containing high flash point paraffin oil according to claim 6, characterized in that, In step S3, the heating temperature is 90-95℃.