High-temperature-resistant pressure-resistant high-hardness rubber composite material and preparation method thereof

Abstract

The invention provides a high-temperature-resistant pressure-resistant high-hardness rubber composite material and a preparation method thereof. The composite material is prepared from the following raw material components in parts by mass: 100 parts of a rubber matrix; 180 parts of an inorganic filler; 4 to 8 parts of peroxide; 2.5 to 5 parts of a co-crosslinking agent; compounding an antioxidant; 1 to 2 parts; 3-6 parts of zinc oxide; 1-2 parts of stearic acid; and 2-5 parts of a processing aid. Therefore, a synergistic effect is formed among the components, and high hardness and high strength of the material are realized on the premise of ensuring processability through the synergistic effect of inorganic filler compounding (nano kaolin and carbon black N550) and a peroxide / TAIC efficient vulcanization system in a specific proportion. A stable cross-linked network formed by a heat-resistant rubber matrix and peroxide / TAIC is combined with a composite antioxidant and anti-aging system, so that the material can keep stable performance for a long time at high temperature and shows extremely low compression set.

Description

Technical Field

[0001] This invention relates to the field of electrochemical technology, and in particular to a high-temperature-resistant, high-pressure-resistant, and high-hardness rubber composite material and its preparation method. Background Technology

[0002] Rubber calendering rollers are crucial components in industrial sectors, particularly in papermaking, textiles, and plastics processing. They are primarily responsible for finishing material surfaces to improve smoothness, gloss, and density. During this process, the rollers must withstand high temperatures (typically exceeding 150°C) and high linear pressures (up to hundreds of kilograms per centimeter). Prolonged operation under such harsh conditions can cause traditional rubber materials to harden, become brittle, and lose elasticity due to molecular chain breakage or excessive cross-linking, leading to reduced calendering performance and even roller surface damage. Furthermore, ozone generated by corona discharge during equipment operation can attack the unsaturated double bonds in the rubber, causing surface cracking and affecting product quality.

[0003] Therefore, developing a composite rubber material that can simultaneously achieve high hardness, high temperature resistance, high pressure resistance, excellent processing performance, and long-term aging resistance is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a high-temperature-resistant, high-pressure-resistant, and high-hardness rubber composite material and its preparation method.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: According to one aspect of this application, a high-temperature-resistant, high-pressure-resistant, and high-hardness rubber composite material is provided, made from raw materials comprising the following components in parts by weight: Rubber matrix: 100 parts; Inorganic filler: 180 parts; Peroxide: 4-8 parts; Co-crosslinking agent: 2.5-5 parts; Compound antioxidant; 1-2 parts; Zinc oxide: 3-6 parts; Stearic acid: 1-2 parts; Processing aids: 2-5 parts.

[0006] In some implementations... The rubber matrix is ​​ethylene propylene diene monomer (EPDM) rubber; And / or the peroxide is 1,4-bis(tert-butylperoxyisopropyl)benzene (BIPB); And / or the co-crosslinking agent is triallyl isocyanurate (TAIC); And / or the antioxidant includes a first antioxidant and a second antioxidant, wherein the mass ratio of the first antioxidant to the second antioxidant is 1:1; And / or the processing aid is polyethylene wax.

[0007] In some embodiments, the inorganic filler includes a first filler and a second filler, wherein the mass ratio of the first filler to the second filler is (4:1) to (6:1). This composite filler system utilizes the small size effect of nanofillers and the excellent reinforcing properties of carbon black N550 to achieve high filling capacity and high hardness while ensuring the strength and wear resistance of the material.

[0008] In some embodiments, the first filler is nano-kaolin with a particle size of 80-120 nm, and the second filler is carbon black N550 with a particle size of 30-50 nm.

[0009] In some embodiments, the first antioxidant is antioxidant 1010; the second antioxidant is antioxidant 168.

[0010] In some embodiments, the raw material components are: EPDM rubber: 100 parts; Inorganic filler: 180 parts; Peroxide: 6 parts; Co-crosslinking agent: 5 parts; Antioxidant 1010: 1 part; Antioxidant 168: 1 part; Zinc oxide: 5 parts; Stearic acid: 1 part; Processing aids: 3 parts.

[0011] According to another aspect of this application, a method for preparing a high-temperature-resistant, high-pressure-resistant, and high-hardness rubber composite material as described above is provided, characterized by comprising the following steps: S1: Add the rubber matrix, compound antioxidant, zinc oxide, stearic acid, and processing aids into the internal mixer according to the ratio, and perform a single mixing at 80-120℃ for 2-5 minutes. Clean the mixture with a hammer to obtain the first mixed rubber compound. S2: Add compounded inorganic fillers to the first mixed rubber compound according to the ratio, and mix at 110-130℃ for 2-4 minutes; S3: Continue to mix the rubber compound obtained in S2 at 130-150℃ for 3-5 minutes, then discharge the rubber and cool it to room temperature; S4: Add peroxide and co-crosslinking agent to the cooled rubber compound in S3 according to the ratio, mix in an internal mixer at 95-110℃ for 1-3 minutes, discharge the rubber after uniform mixing, and obtain the high temperature and pressure resistant, high hardness composite rubber material.

[0012] In some implementations... In step S1, the mixing temperature is 80℃ and the time is 2 minutes. And / or in step S2, the secondary mixing temperature is 130℃; the time is 2 minutes; And / or in step S3, the additional mixing temperature is 150°C; the time is 3 minutes; And / or in step S4, the mixing temperature is 105°C; the time is 2 minutes.

[0013] According to another aspect of this application, there is an application of the aforementioned composite rubber material in the preparation of rubber calendering rollers.

[0014] Compared with the prior art, this application has the following advantages: The EPDM rubber is made of Kumho KEP2480 with high ENB content, ensuring high crosslinking density potential.

[0015] The inorganic filler comprises carbon black N550 and nano-kaolin in a mass ratio of 5:1. The carbon black has a particle size of 39-48 nm, and the nano-kaolin has a particle size of 100 nm. N550 is the main component contributing to high hardness, providing reinforcement, and ensuring strength and wear resistance.

[0016] BIPB peroxide, or 1,4-bis(tert-butylperoxyisopropyl)benzene, offers the advantage of lower odor compared to traditional DCP. Peroxides (such as DCP (bis(diphenylpentaenoyl)) or BIPB) decompose to generate free radicals that directly attack the EPDM molecular chain, forming carbon-carbon (CC) cross-links. The bond energy of the CC bond (350 kJ / mol) is much higher than that of the polysulfide bonds produced by sulfur sulfidation (270 kJ / mol), thus exhibiting excellent heat resistance and extremely low compression set.

[0017] The co-crosslinking agent TAIC, triallyl isocyanurate, is a key component that works synergistically with peroxides to achieve high hardness, high strength, and high resistance to compression set. These are multifunctional monomers that significantly improve the crosslinking efficiency of peroxides, forming a denser and more uniform three-dimensional network. This significantly enhances the hardness, modulus, and tear strength of the vulcanizate, and further reduces compression set. Without the co-crosslinking agent, it is difficult to achieve stable ultra-high hardness with EPDM.

[0018] Antioxidant 1010 and Antioxidant 168 are used together; one is responsible for capturing free radicals, and the other is responsible for decomposing hydrogen peroxide, providing long-lasting heat protection.

[0019] Polyethylene wax, a processing aid, makes the rubber compound extremely hard and tough due to its very high filler content, making it difficult to process. As an internal lubricant, it improves filler dispersion, reduces compound viscosity, and enhances flowability.

[0020] The various components work synergistically, and through the specific ratio of inorganic filler (nano-kaolin and carbon black N550) and the synergistic effect of the peroxide / TAIC high-efficiency vulcanization system, high hardness and high strength are achieved while ensuring processability. The stable cross-linked network formed by the heat-resistant rubber matrix and the peroxide / TAIC, combined with the composite antioxidant and anti-aging system, enables the material to maintain stable performance at high temperatures for a long time and exhibits extremely low compression set. Detailed Implementation

[0021] The present invention will be further described below with reference to the embodiments and effect data.

[0022] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0023] I. Specific Implementation Examples and Comparative Examples Example 1 This embodiment provides a high-temperature-resistant, high-pressure-resistant, and high-hardness composite rubber material, the raw material composition (parts by weight) of which is as follows: The composition includes 100 parts EPDM rubber, 180 parts inorganic filler, 6 parts BIPB peroxide, 4 parts TAIC co-crosslinking agent, 1 part antioxidant 1010, 1 part antioxidant 168, 5 parts zinc oxide, 1 part stearic acid, and 3 parts polyethylene wax. The inorganic filler is a mixture of carbon black N550 and nano-kaolin in a 5:1 mass ratio, specifically 150 parts carbon black N550 and 30 parts nano-kaolin. The carbon black N550 has a particle size of 39-48 nm, and the nano-kaolin has a particle size of 100 nm.

[0024] The grades of each component are: EPDM rubber KEP2480, carbon black CABOT N550, nano kaolin NCL-302, peroxide BIBP, co-crosslinking agent TAIC, antioxidant EP1010, antioxidant Irgafos 168, zinc oxide ZNOA, stearic acid SA, and polyethylene wax AC617.

[0025] Among them, the EPDM rubber is Kumho KEP2480 with high ENB content, ensuring high crosslinking density potential.

[0026] The preparation method includes the following steps: S1: Add EPDM rubber, antioxidant 1010, antioxidant 168, zinc oxide, stearic acid, and polyethylene wax into a mixer according to the specified ratio, mix for 2 minutes until the temperature reaches 80°C, then remove the hammer and clean.

[0027] S2: Second step, add inorganic filler according to the ratio, mix for 2 minutes until 120℃, then remove the hammer and clean.

[0028] S3: The third step is to mix for about 3 minutes until it reaches 150°C, then remove the glue and cool to room temperature.

[0029] S4: Add BIPB peroxide and TAIC co-crosslinking agent to the cooled rubber compound in S3 according to the ratio, mix in an internal mixer for about 2 minutes until it reaches 105°C, discharge the rubber after it is uniform, and you will get the high temperature and pressure resistant high hardness composite rubber material.

[0030] Example 2 The difference from Example 1 is that the raw material composition (parts by weight) is as follows: 100 parts EPDM rubber, 180 parts inorganic filler, 3.75 parts BIPB peroxide, 2.5 parts co-crosslinking agent TAIC, 1 part antioxidant 1010, 1 part antioxidant 168, 3 parts zinc oxide, 1 part stearic acid, and 2 parts polyethylene wax. Everything else is exactly the same as in Example 1.

[0031] Example 3 The difference from Example 1 is that the raw material composition (parts by weight) is as follows: 100 parts EPDM rubber, 180 parts inorganic filler, 7.5 parts BIPB peroxide, 5 parts TAIC co-crosslinking agent, 1 part antioxidant 1010, 1 part antioxidant 168, 6 parts zinc oxide, 2 parts stearic acid, and 5 parts polyethylene wax. Everything else is exactly the same as in Example 1.

[0032] Comparative Example 1 The difference from Example 1 is that the co-crosslinking agent TAIC was adjusted to 0 parts; the remaining components, dosages, and preparation methods are exactly the same as in Example 1.

[0033] Comparative Example 2 The difference from Example 1 is that the amount of carbon black N550 was adjusted to 180 parts and nano-kaolin to 0 parts; the other components, amounts, and preparation methods are exactly the same as in Example 1.

[0034] Comparative Example 3 The difference from Example 1 is that the amount of stearic acid was adjusted to 0 parts; the other components, amounts, and preparation methods are exactly the same as in Example 1.

[0035] Comparative Example 4 The difference from Example 1 is that the amount of zinc oxide was adjusted to 0 parts; the other components, amounts, and preparation methods are exactly the same as in Example 1.

[0036] Comparative Example 5 The difference from Example 1 is that the amount of polyethylene wax was adjusted to 0 parts; the remaining components, amounts, and preparation methods are exactly the same as in Example 1.

[0037] Comparative Example 6 The difference from Example 1 is that the ratio of carbon black N550 to nano-kaolin in the inorganic filler was adjusted to 8:1, that is, the amount of carbon black N550 was 160 parts and the amount of nano-kaolin was 20 parts. The remaining components, amounts, and preparation methods are exactly the same as in Example 1.

[0038] Comparative Example 7 The difference from Example 1 is that the ratio of carbon black N550 to nano-kaolin in the inorganic filler was adjusted to 2:1, that is, the amount of carbon black N550 was 120 parts and the amount of nano-kaolin was 60 parts. The remaining components, amounts, and preparation methods are exactly the same as in Example 1.

[0039] Comparative Example 8 The difference from Example 1 is that the amount of BIBP peroxide was adjusted to 8 parts and the amount of TAIC was adjusted to 3.2 parts. The other components, amounts, and preparation methods are exactly the same as in Example 1.

[0040] Comparative Example 9 The difference from Example 1 is that the amount of BIBP peroxide was adjusted to 6 parts and the amount of TAIC was adjusted to 2 parts, while the other components, amounts, and preparation methods are exactly the same as in Example 1.

[0041] Comparative Example 10 The difference from Example 1 is that the amount of antioxidant 1010 is adjusted to 0.5 parts; the amount of antioxidant 168 is 1 part, and the remaining components, amounts, and preparation methods are exactly the same as in Example 1.

[0042] Comparative Example 11 The difference from Example 1 is that the amount of antioxidant 1010 is adjusted to 1 part; the amount of antioxidant 168 is adjusted to 0.5 parts, and the remaining components, amounts, and preparation methods are exactly the same as in Example 1.

[0043] The proportions of the above embodiments and comparative examples can be found in Table 1 below: Examples and comparative formulations (based on 100 parts by weight of rubber matrix) Table 1 - Examples and Comparative Examples

[0044] All of the above components are commercially available.

[0045] II. Experimental Results Data of Examples and Comparative Examples The materials in the above embodiments and comparative examples were subjected to performance tests. Specifically, the tests were conducted in accordance with the following standards: GB / T 531.1 "Test Method for Indentation Hardness of Vulcanized Rubber or Thermoplastic Rubber - Part 1: Shore Hardness Tester Method (Shore Hardness)", GB / T 528-2009 "Determination of Tensile Stress-Strain Properties of Vulcanized Rubber or Thermoplastic Rubber", GB / T 529-2008 "Determination of Tear Strength of Vulcanized Rubber or Thermoplastic Rubber (Pants-Shaped, Right-Angle and Crescent-Shaped Specimens)", GB / T 7759.1-2015 "Determination of Compression Set of Vulcanized Rubber or Thermoplastic Rubber - Part 1: Under Normal and High Temperature Conditions", GB / T 7762-2014 "Static Tensile Test for Ozone Cracking Resistance of Vulcanized Rubber or Thermoplastic Rubber", and GB / T 5762-2014 "Accelerated Aging and Heat Resistance Test of Vulcanized Rubber or Thermoplastic Rubber in Hot Air". The performance was tested according to GB / T9867-2008, "Determination of abrasion resistance of vulcanized rubber or thermoplastic rubber (rotary roller abrasion mill method)" (GB 3512-2014). The performance test results are shown in Table 2 below: Table 2 - Performance Test Results:

[0046] Based on the above embodiments and comparative data, the technical solution of this application can achieve the following performance: Shore hardness A is 95±2; tensile strength / MPa ≥15; elongation at break / % ≥100; tear strength kN / m ≥25; compression set / % (22h×125°C) ≤20; hardness change after hot air aging (70h×125°C) ±3; DIN abrasion / mm3 ≤100; ozone resistance 50pphmx72Hx40℃x20% without cracking.

[0047] This application is not a simple sum of the functions of its components, but rather a solution to the series of mutually restrictive technical challenges of simultaneously requiring high-hardness rubber materials to possess high temperature resistance, pressure resistance, low deformation, aging resistance, and processability through the careful design and synergistic cooperation of each component. The comparative data from the examples and comparative examples clearly demonstrate the specific roles and synergistic effects of each functional component, proving the inventiveness and superior effectiveness of the invention. Through the synergistic effect of a specific ratio of inorganic filler compound (carbon black N550 and nano-kaolin) and a peroxide / TAIC high-efficiency vulcanization system, high hardness and high strength of the material are achieved while ensuring processability. The stable cross-linked network formed by the heat-resistant rubber matrix and the peroxide / TAIC, combined with the composite antioxidant and anti-aging system, enables the material to maintain stable performance at high temperatures for a long period and exhibits extremely low compression set.

[0048] The above descriptions are merely some embodiments of the present invention. It should be noted that those skilled in the art can make other modifications and improvements without departing from the inventive concept of the present invention, and these all fall within the protection scope of the present invention.

Claims

1. A high-temperature-resistant, high-pressure-resistant, and high-hardness rubber composite material, characterized in that, Made from raw materials comprising the following components in parts by weight: Rubber matrix: 100 parts; Composite inorganic filler: 180 parts; Peroxide: 3.75-7.5 parts; The co-crosslinking agent is 2.5-5 parts; Compound antioxidant; 1-2 parts; Zinc oxide: 3-6 parts; Stearic acid: 1-2 parts; Processing aids: 2-5 parts.

2. The rubber composite material according to claim 1, characterized in that, The rubber matrix is ​​ethylene propylene diene monomer (EPDM) rubber; And / or the peroxide is 1,4-bis(tert-butylperoxyisopropyl)benzene (BIPB); And / or the co-crosslinking agent is triallyl isocyanurate (TAIC); And / or the compound antioxidant includes a first antioxidant and a second antioxidant, wherein the mass ratio of the first antioxidant to the second antioxidant is 1:1; And / or the mass ratio of the peroxide and co-crosslinking agent is 3:2; And / or the processing aid is polyethylene wax.

3. The rubber composite material according to claim 1, characterized in that, The inorganic packing includes a first packing and a second packing, and the mass ratio of the first packing to the second packing is (4:1) to (6:1).

4. The rubber composite material according to claim 3, characterized in that, The first filler is carbon black N550 with a particle size of 30-50nm, and the second filler is nano-kaolin with a particle size of 80-120nm.

5. The rubber composite material according to claim 4, characterized in that, The first antioxidant is antioxidant 1010; the second antioxidant is antioxidant 168.

6. The rubber composite material according to claim 5, characterized in that, The raw material components are: EPDM rubber: 100 parts; Inorganic filler: 180 parts; Peroxide: 6 parts; Co-crosslinking agent: 5 parts; Antioxidant 1010: 1 part; Antioxidant 168: 1 part; Zinc oxide: 5 parts; Stearic acid: 1 part; Processing aids: 3 parts.

7. A method for preparing a high-temperature-resistant, high-pressure-resistant, and high-hardness rubber composite material as described in any one of claims 1-6, characterized in that, Includes the following steps: S1: Add the rubber matrix, compound antioxidant, zinc oxide, stearic acid, and processing aids into the internal mixer according to the ratio, and perform a single mixing at 80-120℃ for 2-5 minutes. Clean the mixture with a hammer to obtain the first mixed rubber compound. S2: Add compounded inorganic fillers to the first mixed rubber compound according to the ratio, and mix at 110-130℃ for 2-4 minutes; S3: Continue to mix the rubber compound obtained in S2 at 130-150℃ for 3-5 minutes, then discharge the rubber and cool it to room temperature; S4: Add peroxide and co-crosslinking agent to the cooled rubber compound in S3 according to the ratio, mix in an internal mixer at 95-110℃ for 1-3 minutes, discharge the rubber after uniform mixing, and obtain the high temperature and pressure resistant, high hardness composite rubber material.

8. The method according to claim 7, characterized in that, In step S1, the mixing temperature is 80℃ and the time is 2 minutes. And / or in step S2, the mixing temperature is 120°C; the time is 2 minutes; And / or in step S3, the mixing temperature is 150°C; the time is 3 minutes; And / or in step S4, the mixing temperature is 105°C; the time is 2 minutes.

9. The application of the composite rubber material according to any one of claims 1-6 in the preparation of rubber calendering rollers.

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