Anti-aging rare earth butadiene-isoprene rubber material and preparation method thereof

Abstract

The invention belongs to the technical field of materials, and discloses an anti-aging rare earth butadiene-isoprene rubber material and a preparation method thereof.The anti-aging rare earth butadiene-isoprene rubber material is prepared by taking rare earth butadiene-isoprene rubber as a base material and taking an inorganic reinforced additive, a composite anti-aging agent and the like as auxiliary materials through mixing and extrusion; wherein the inorganic reinforced additive is prepared by modifying epoxidized natural rubber on the surface of filler illite, and after surface modification, illite can exist in the material in a physical crosslinking core form, so that good stress absorption and stress dispersion effects can be generated, and the mechanical property of the material is enhanced; the compound type anti-aging agent structure not only contains an ammonia anti-aging agent, but also contains a benzimidazole anti-aging agent, so that a synergistic anti-aging effect can be realized through different action principles and action stages, and the anti-aging performance of the material is effectively enhanced.

Description

Technical Field

[0001] This invention belongs to the field of materials technology, specifically relating to an anti-aging rare earth butadiene-isoprene rubber material and its preparation method. Background Technology

[0002] Rare earth butadiene-isoprene rubber is a product of combining rare earth catalysis with isoprene monomer polymerization technology. Its core advantage lies in the directional synthesis of high cis-structure polymers through the unique chemical properties of rare earth elements. As a representative of synthetic natural rubber, it features good molecular chain regularity, high raw rubber strength, and high cohesive energy density, and can be widely used in high-end rubber products such as tires, hoses, and seals.

[0003] Despite its structural and performance advantages, rare earth butadiene-isoprene rubber (REEB) faces two major challenges in practical applications. First, due to the low bond energy of the unsaturated bonds in its molecular chains, it is prone to oxidative decomposition under high temperatures or metal residue conditions. This leads to chain breakage, cross-linking destruction, and the generation of low-molecular-weight oxygen-containing compounds, making it highly susceptible to aging, resulting in yellowing and powdering, affecting material performance and shortening its lifespan. Second, the poor mechanical properties of REB fail to meet the application requirements of some high-end fields, significantly limiting its further development and application.

[0004] At present, it is common to improve the comprehensive performance of rare earth butadiene-isoprene rubber by using filler modification. However, uneven dispersion of fillers can form stress concentration points, which can have a negative impact on the performance of the material. Based on this, the present invention provides a rare earth butadiene-isoprene rubber composite material that can solve the problems existing in the prior art. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide an anti-aging butadiene-isoprene rubber material and its preparation method.

[0006] In a first aspect, the present invention provides an anti-aging rare earth butadiene-isoprene rubber material, comprising the following raw materials in parts by weight:

[0007] Rare earth butadiene-isoprene rubber 60-75 parts, inorganic reinforcing additives 2-5 parts, composite antioxidant 0.5-1 part, pigment 5-10 parts, microcrystalline wax 1-3 parts;

[0008] The inorganic reinforcing additive is illite with epoxidized natural rubber grafted onto its surface.

[0009] As a preferred embodiment of the present invention, the method for preparing the inorganic reinforcing additive includes the following steps:

[0010] Step S1: Disperse illite in toluene, then add isocyanate monomer and tin catalyst to the formed uniform dispersion. After the addition is complete, raise the temperature to 70-80℃ and keep it at this temperature for 4-8 hours. Then stop heating, cool down and discharge the material. After separating the solid material, add it to deionized water and hydrolyze it at 80-90℃ for 2-4 hours. Centrifuge the solid material, wash it, and vacuum dry it to obtain the modified illite material.

[0011] Step S2: Add illite modifier to xylene. After addition, ultrasonically disperse the mixture evenly. Then raise the temperature to 80-100℃ and add epoxidized natural rubber. After addition, continue to heat and stir for 6-9 hours. Stop heating, cool down and discharge the material. Collect the solid material, wash and vacuum dry it to obtain inorganic reinforcing additive.

[0012] As a preferred embodiment of the present invention, in step S1, the isocyanate monomer is any one of toluene diisocyanate, isophorone diisocyanate, or diphenylmethane diisocyanate.

[0013] As a preferred embodiment of the present invention, in step S1, the tin catalyst is any one of methyl tin mercaptan, octyl tin mercaptan, dibutyltin dilaurate, or dibutyltin diacetate.

[0014] As a preferred embodiment of the present invention, in step S2, the mass ratio of the illite modified material to the epoxidized natural rubber is 1:0.4-0.6.

[0015] It should be noted that in the above technical solution, firstly, isocyanate monomers are used to modify the surface of illite to obtain illite with isocyanate groups on the surface. Then, through a hydrolysis reaction, the isocyanate groups are hydrolyzed into primary amines to obtain illite with active primary amine substituents on the surface, i.e., illite modified material. Next, under high temperature conditions, the primary amines of illite modified material can undergo ring-opening addition with the epoxy groups in the epoxidized natural rubber structure, thereby modifying the epoxidized natural rubber on the surface of illite to obtain an inorganic reinforcing additive.

[0016] As a preferred embodiment of the present invention, the composite antioxidant is prepared by the following method:

[0017] 2-Methyl-N-[4-(phenylamino)phenyl]-2-acrylamide and 2-mercaptobenzimidazole were added to tetrahydrofuran, stirred, and mixed evenly. Nitrogen gas was introduced for protection, and heating was started to raise the temperature to 60-65℃. The catalyst was then added. After the addition was complete, stirring was continued for 8-12 hours. The solvent was evaporated to remove the product, which was then collected, washed, and vacuum dried to obtain the composite antioxidant.

[0018] As a preferred embodiment of the present invention, the molar ratio of 2-methyl-N-[4-(phenylamino)phenyl]-2-acrylamide and 2-mercaptobenzimidazole is 1:1.

[0019] As a preferred embodiment of the present invention, the catalyst is triethylamine.

[0020] In the above technical solution, 2-methyl-N-[4-(phenylamino)phenyl]-2-acrylamide and 2-mercaptobenzimidazole are used as raw materials. Under the catalysis of triethylamine, the unsaturated alkenyl substituents in their structures can undergo click-catalysis with the thiol functional groups to obtain a composite antioxidant containing both amine-based and benzimidazole antioxidants.

[0021] As a preferred embodiment of the present invention, the pigment is any one of titanium dioxide, carbon black, or calcium carbonate.

[0022] A second aspect of the present invention provides a method for preparing an anti-aging rare earth butadiene-isoprene rubber material, comprising the following steps:

[0023] Step 1: Weigh and prepare all the raw materials according to their weight proportions;

[0024] The second step is to add all the raw materials to a high-speed mixer, control the speed to be 300-500 r / min and the temperature to be 80-100℃, and mechanically mix them evenly. Then, transfer the resulting uniform mixture to an extruder for melt extrusion granulation and discharge.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) This invention obtains an inorganic reinforcing additive by modifying the surface of illite with epoxidized natural rubber. Since epoxidized natural rubber and rare earth butadiene-isoprene rubber have good compatibility, their molecular chains will intertwine and form a physical cross-linking network during melt extrusion. This causes illite to exist in the material in the form of a physical cross-linking core, which can produce good stress absorption and stress dispersion effects, effectively avoid stress concentration, and thus enhance the mechanical properties of the material by utilizing the advantages of illite and natural rubber.

[0027] (2) The composite antioxidant structure prepared by the present invention contains both amine antioxidants and benzimidazole antioxidants. The amine antioxidant structure can capture free radicals and interrupt the chain reaction of rubber, while the benzimidazole antioxidant structure mainly decomposes the peroxides produced by rubber oxidation to form stable non-free radical products. They can achieve synergistic anti-aging effects through different mechanisms and stages of action, thereby effectively enhancing the anti-aging performance of the material. Detailed Implementation

[0028] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0029] Example 1

[0030] This embodiment provides an anti-aging rare earth butadiene-isoprene rubber material, which, by weight, comprises the following raw materials:

[0031] 60 parts rare earth butadiene-isoprene rubber, 2 parts inorganic reinforcing additives, 0.5 parts composite antioxidant, 5 parts carbon black, and 1 part microcrystalline wax;

[0032] The preparation method of the rare earth butadiene-isoprene rubber material includes the following steps:

[0033] Step 1: Weigh and prepare all the raw materials according to their weight proportions;

[0034] The second step is to add all the raw materials to a high-speed mixer, control the speed to 300 r / min and the temperature to 100℃, and mechanically mix them evenly. Then, transfer the resulting uniform mixture to an extruder for melt extrusion granulation and discharge.

[0035] The preparation method of the inorganic reinforcing additive includes the following steps:

[0036] Step S1: Disperse 1.8g illite in toluene, then add 0.5g diphenylmethane diisocyanate and 0.01g dibutyltin dilaurate to the formed uniform dispersion. After the addition is complete, raise the temperature to 75℃ and keep it at this temperature for 6 hours. Then stop heating, cool down and discharge the material. After separating the solid material, add it to 100mL of deionized water and hydrolyze it at 90℃ for 3 hours. Centrifuge to remove the solid material, wash it, and vacuum dry it to obtain the modified illite material.

[0037] Step S2: Add 1.5g illite modifier to xylene. After addition, ultrasonically disperse the mixture evenly. Then raise the temperature to 90℃ and add 0.8g epoxidized natural rubber. After addition, continue to heat and stir for 8 hours. Stop heating, cool down and discharge the material. Collect the solid material, wash and vacuum dry it to obtain inorganic reinforcing additive.

[0038] The composite antioxidant is prepared using the following method:

[0039] 0.6 g of 2-methyl-N-[4-(phenylamino)phenyl]-2-acrylamide and 0.36 g of 2-mercaptobenzimidazole were added to tetrahydrofuran. The mixture was stirred until homogeneous, then nitrogen gas was introduced for protection. The mixture was heated to 65°C, and 0.1 g of triethylamine was added. After the addition was complete, the mixture was stirred continuously for 9 hours. The solvent was evaporated and the product was collected. The product was washed and vacuum dried to obtain a composite antioxidant.

[0040] Example 2

[0041] This embodiment provides an anti-aging rare earth butadiene-isoprene rubber material, which, by weight, comprises the following raw materials:

[0042] 65 parts rare earth butadiene-isoprene rubber, 4 parts inorganic reinforcing additives, 0.8 parts composite antioxidant, 6 parts carbon black, and 2 parts microcrystalline wax;

[0043] The preparation method of the rare earth butadiene-isoprene rubber material includes the following steps:

[0044] Step 1: Weigh and prepare all the raw materials according to their weight proportions;

[0045] The second step is to add all the raw materials to a high-speed mixer, control the speed to 500 r / min and the temperature to 100℃, and mechanically mix them evenly. Then, transfer the resulting uniform mixture to an extruder for melt extrusion granulation and discharge.

[0046] The preparation methods of the inorganic reinforcing additives and composite antioxidants are the same as those in Example 1.

[0047] Example 3

[0048] This embodiment provides an anti-aging rare earth butadiene-isoprene rubber material, which, by weight, comprises the following raw materials:

[0049] 75 parts rare earth butadiene-isoprene rubber, 5 parts inorganic reinforcing additives, 1 part composite antioxidant, 10 parts carbon black, and 3 parts microcrystalline wax;

[0050] The preparation method of the rare earth butadiene-isoprene rubber material includes the following steps:

[0051] Step 1: Weigh and prepare all the raw materials according to their weight proportions;

[0052] The second step is to add all the raw materials to a high-speed mixer, control the speed to 500 r / min and the temperature to 100℃, and mechanically mix them evenly. Then, transfer the resulting uniform mixture to an extruder for melt extrusion granulation and discharge.

[0053] The preparation methods of the inorganic reinforcing additives and composite antioxidants are the same as those in Example 1.

[0054] Comparative Example 1

[0055] This comparative example provides an anti-aging rare earth butadiene-isoprene rubber material, which, by weight parts, comprises the following raw materials:

[0056] 65 parts rare earth butadiene-isoprene rubber, 4 parts illite, 0.8 parts composite antioxidant, 6 parts carbon black, and 2 parts microcrystalline wax;

[0057] The preparation method of the rare earth butadiene-isoprene rubber material includes the following steps:

[0058] Step 1: Weigh and prepare all the raw materials according to their weight proportions;

[0059] The second step is to add all the raw materials to a high-speed mixer, control the speed to 500 r / min and the temperature to 100℃, and mechanically mix them evenly. Then, transfer the resulting uniform mixture to an extruder for melt extrusion granulation and discharge.

[0060] The preparation method of the composite antioxidant is the same as that in Example 1.

[0061] Comparative Example 2

[0062] This comparative example provides an anti-aging rare earth butadiene-isoprene rubber material, which, by weight parts, comprises the following raw materials:

[0063] 65 parts rare earth butadiene-isoprene rubber, 0.8 parts composite antioxidant, 6 parts carbon black, and 2 parts microcrystalline wax;

[0064] The preparation method of the rare earth butadiene-isoprene rubber material includes the following steps:

[0065] Step 1: Weigh and prepare all the raw materials according to their weight proportions;

[0066] The second step is to add all the raw materials to a high-speed mixer, control the speed to 500 r / min and the temperature to 100℃, and mechanically mix them evenly. Then, transfer the resulting uniform mixture to an extruder for melt extrusion granulation and discharge.

[0067] The preparation method of the composite antioxidant is the same as that in Example 1.

[0068] Comparative Example 3

[0069] This embodiment provides an anti-aging rare earth butadiene-isoprene rubber material, which, by weight, comprises the following raw materials:

[0070] Rare earth butadiene-isoprene rubber 65 parts, inorganic reinforcing additives 4 parts, 2-mercaptobenzimidazole 0.8 parts, carbon black 6 parts, microcrystalline wax 2 parts;

[0071] The preparation method of the rare earth butadiene-isoprene rubber material includes the following steps:

[0072] Step 1: Weigh and prepare all the raw materials according to their weight proportions;

[0073] The second step is to add all the raw materials to a high-speed mixer, control the speed to 500 r / min and the temperature to 100℃, and mechanically mix them evenly. Then, transfer the resulting uniform mixture to an extruder for melt extrusion granulation and discharge.

[0074] The preparation method of the inorganic reinforcing additive is the same as that in Example 1.

[0075] Comparative Example 4

[0076] This embodiment provides an anti-aging rare earth butadiene-isoprene rubber material, which, by weight, comprises the following raw materials:

[0077] Rare earth butadiene-isoprene rubber 65 parts, inorganic reinforcing additives 4 parts, carbon black 6 parts, microcrystalline wax 2 parts;

[0078] The preparation method of the rare earth butadiene-isoprene rubber material includes the following steps:

[0079] Step 1: Weigh and prepare all the raw materials according to their weight proportions;

[0080] The second step is to add all the raw materials to a high-speed mixer, control the speed to 500 r / min and the temperature to 100℃, and mechanically mix them evenly. Then, transfer the resulting uniform mixture to an extruder for melt extrusion granulation and discharge.

[0081] The preparation method of the inorganic reinforcing additive is the same as that in Example 1.

[0082] The materials provided in the above embodiments and comparative examples were subjected to performance tests, and the test methods are as follows:

[0083] Tensile strength was tested according to standard GB / T 1040.1-2018. After the test, samples of the same batch and specifications were placed in a temperature environment of 120℃ for accelerated aging treatment for 24 hours, and the tensile strength was tested again. The tensile strength reduction rate was calculated to evaluate the anti-aging performance of the material.

[0084] The performance test data above are shown in Table 1.

[0085] Table 1 Performance Test Results

[0086]

[0087]

[0088] As can be seen from the above, the materials prepared in the embodiments of the present invention have good mechanical properties and anti-aging properties. Replacing the inorganic reinforcing additives with unmodified illite results in a decreased reinforcing effect due to dispersibility issues. Replacing the composite antioxidant with 2-mercaptobenzimidazole significantly reduces the anti-aging properties of the material.

[0089] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention, including the best mode, and also to enable any person skilled in the art to practice the present invention, including manufacturing and using any device or system, and implementing any combined method. It should be noted that for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the present invention.

Claims

1. An anti-aging rare earth butadiene-isoprene rubber material, characterized in that, By weight, it includes the following ingredients: Rare earth butadiene-isoprene rubber 60-75 parts, inorganic reinforcing additives 2-5 parts, composite antioxidant 0.5-1 part, pigment 5-10 parts, microcrystalline wax 1-3 parts; The inorganic reinforcing additive is illite with epoxidized natural rubber grafted onto its surface.

2. The anti-aging rare earth butadiene-isoprene rubber material according to claim 1, characterized in that, The preparation method of the inorganic reinforcing additive includes the following steps: Step S1: Disperse illite in toluene, then add isocyanate monomer and tin catalyst to the formed uniform dispersion. After the addition is complete, raise the temperature to 70-80℃ and keep it at this temperature for 4-8 hours. Then stop heating, cool down and discharge the material. After separating the solid material, add it to deionized water and hydrolyze it at 80-90℃ for 2-4 hours. Centrifuge the solid material, wash it, and vacuum dry it to obtain the modified illite material. Step S2: Add illite modifier to xylene. After addition, ultrasonically disperse the mixture evenly. Then raise the temperature to 80-100℃ and add epoxidized natural rubber. After addition, continue to heat and stir for 6-9 hours. Stop heating, cool down and discharge the material. Collect the solid material, wash and vacuum dry it to obtain inorganic reinforcing additive.

3. The anti-aging rare earth butadiene-isoprene rubber material according to claim 2, characterized in that, In step S1, the isocyanate monomer is any one of toluene diisocyanate, isophorone diisocyanate, or diphenylmethane diisocyanate.

4. The anti-aging rare earth butadiene-isoprene rubber material according to claim 2, characterized in that, In step S1, the tin catalyst is any one of methyl tin mercaptan, octyl tin mercaptan, dibutyltin dilaurate, or dibutyltin diacetate.

5. The anti-aging rare earth butadiene-isoprene rubber material according to claim 2, characterized in that, In step S2, the mass ratio of the illite modified material to the epoxidized natural rubber is 1:0.4-0.

6.

6. The anti-aging rare earth butadiene-isoprene rubber material according to claim 1, characterized in that, The composite antioxidant is prepared using the following method: 2-Methyl-N-[4-(phenylamino)phenyl]-2-acrylamide and 2-mercaptobenzimidazole were added to tetrahydrofuran, stirred, and mixed evenly. Nitrogen gas was introduced for protection, and heating was started to raise the temperature to 60-65℃. The catalyst was then added. After the addition was complete, stirring was continued for 8-12 hours. The solvent was evaporated to remove the product, which was then collected, washed, and vacuum dried to obtain the composite antioxidant.

7. The anti-aging rare earth butadiene-isoprene rubber material according to claim 6, characterized in that, The molar ratio of 2-methyl-N-[4-(phenylamino)phenyl]-2-acrylamide to 2-mercaptobenzimidazole is 1:

1.

8. The anti-aging rare earth butadiene-isoprene rubber material according to claim 6, characterized in that, The catalyst is triethylamine.

9. The anti-aging rare earth butadiene-isoprene rubber material according to claim 1, characterized in that, The pigment is any one of titanium dioxide, carbon black, or calcium carbonate.

10. A method for preparing the anti-aging rare earth butadiene-isoprene rubber material as described in claim 1, characterized in that, Includes the following steps: Step 1: Weigh and prepare all the raw materials according to their weight proportions; The second step is to add all the raw materials to a high-speed mixer, control the speed to be 300-500 r / min and the temperature to be 80-100℃, and mechanically mix them evenly. Then, transfer the resulting uniform mixture to an extruder for melt extrusion granulation and discharge.

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