Cross-linked elastomer composition, cross-linked elastomer and preparation method of cross-linked elastomer

Abstract

The invention relates to the field of rubber materials, and discloses a composition of a cross-linked elastomer, the cross-linked elastomer and a preparation method of the cross-linked elastomer, the composition comprises base rubber, an epoxidized reinforcing filler and a transesterification catalyst, wherein the base rubber is carboxyl hydrogenated nitrile rubber and / or carboxyl nitrile rubber; relative to 100 parts by weight of base rubber, the content of the epoxidized reinforcing filler is 10-70 parts by weight, and the content of the ester exchange catalyst is 0.5-10 parts by weight; the grafting rate of epoxy groups in the epoxidized reinforcing filler is 10-50%. The cross-linked elastomer prepared by the preparation method disclosed by the invention has high mechanical property and excellent repeatable processing property at the same time.

Description

Technical Field

[0001] The present invention relates to the technical field of rubber materials, and specifically, to a composition of a crosslinked elastomer, the crosslinked elastomer, and a preparation method thereof. Background Art

[0002] The excellent mechanical properties, high resilience, and weather resistance of rubber materials largely depend on the permanent covalent crosslinked network obtained through vulcanization. Only when the rubber material transforms from a linear structure to a three-dimensional network structure can it be transformed into a useful rubber product. However, the sulfur and peroxide crosslinking methods widely used in the current rubber industry have the following inevitable problems: The accelerators in the rubber vulcanization system are toxic themselves, and toxic, carcinogenic, and unpleasant VOCs will be released during the crosslinking process; problems such as "blooming" and "reversion of vulcanization" occur during rubber processing and application; the permanent crosslinked network makes recycling inherently difficult, resulting in serious black pollution problems. Approximately 1 billion tires are discarded every year, and the number is increasing at a rate of about 8%-10% per year. Most of them are recycled through grinding or pyrolysis, and the rest are disposed of by incineration or landfill, posing a serious threat to the ecological environment and causing waste of resources. Although some waste rubber is prepared into reclaimed rubber by desulfurizing and cutting crosslinking bonds, traditional desulfurization technologies have problems such as high production energy consumption, difficult treatment of three wastes, and low economic benefits.

[0003] With the increasing application of special rubbers in high-temperature environments, the consumption of rubber is increasing, and the resulting waste rubber will also be increasing.

[0004] Therefore, there is an urgent need for a rubber with high mechanical properties, and at the same time, the rubber also has excellent reprocessability. Summary of the Invention

[0005] The purpose of the present invention is to overcome the problem that the existing crosslinked elastomers are difficult to balance mechanical properties and reprocessability, and to provide a composition of a crosslinked elastomer, the crosslinked elastomer, and a preparation method thereof. The crosslinked elastomer prepared from the composition of the crosslinked elastomer has high mechanical properties and, at the same time, excellent reprocessability.

[0006] To achieve the above purpose, in the first aspect of the present invention, a composition of a crosslinked elastomer is provided, wherein the composition includes: a base rubber, an epoxidized reinforcing filler, and a transesterification catalyst;

[0007] Wherein, the base rubber is carboxyl hydrogenated nitrile rubber and / or carboxyl nitrile rubber;

[0008] Relative to 100 parts by weight of the base rubber, the content of the epoxidized reinforcing filler is 10-70 parts by weight, and the transesterification catalyst is 0.5-10 parts by weight;

[0009] The grafting rate of epoxy groups in the epoxidized reinforcing filler is 10-50%.

[0010] In the second aspect of the present invention, a crosslinked elastomer is provided, wherein the crosslinked elastomer is prepared by kneading and vulcanizing the composition of the above crosslinked elastomer.

[0011] In the third aspect of the present invention, a method for preparing the above crosslinked elastomer is provided, wherein the method includes: kneading and vulcanizing a base rubber, an epoxidized reinforcing filler, and a transesterification catalyst to obtain the crosslinked elastomer;

[0012] The grafting rate of epoxy groups in the epoxidized reinforcing filler is 10-50%.

[0013] Through the above technical solutions, the composition of the crosslinked elastomer, the crosslinked elastomer, and the preparation method thereof provided by the present invention have the following beneficial effects:

[0014] In the composition of the crosslinked elastomer of the present invention, carboxyl hydrogenated nitrile rubber and / or carboxyl nitrile rubber can generate a dynamic crosslinked structure with epoxy groups in the epoxidized reinforcing filler. When the base rubber and the epoxidized reinforcing filler with a specific grafting rate are used in specific amounts, the prepared crosslinked elastomer has high mechanical properties and excellent reprocessability. Detailed Embodiments

[0015] In the ranges disclosed herein, the endpoints and any values are not limited to the exact ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of each range, between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein.

[0016] In the first aspect of the present invention, a composition of a crosslinked elastomer is provided, wherein the composition includes: a base rubber, an epoxidized reinforcing filler, and a transesterification catalyst;

[0017] Wherein, the base rubber is carboxyl hydrogenated nitrile rubber and / or carboxyl nitrile rubber;

[0018] Relative to 100 parts by weight of the base rubber, the content of the epoxidized reinforcing filler is 10-70 parts by weight, and the transesterification catalyst is 0.5-10 parts by weight;

[0019] The grafting rate of epoxy groups in the epoxidized reinforcing filler is 10-50%.

[0020] In the present invention, the carboxylated hydrogenated nitrile rubber and / or carboxylated nitrile rubber can form a dynamic crosslinked structure with the epoxy groups in the epoxidized reinforcing filler. When the base rubber and the epoxidized reinforcing filler with a specific grafting rate are used in specific amounts, the resulting crosslinked elastomer has high mechanical properties and, at the same time, excellent reprocessability.

[0021] In the present invention, the grafting rate of the epoxy groups in the epoxidized reinforcing filler is measured by the thermogravimetric TGA method, in a nitrogen atmosphere, at a temperature of 40 - 800 °C, with a heating rate of 10 °C / min. In the present invention, the grafting rate of the epoxy groups in the epoxidized reinforcing filler refers to the grafting rate of the silane coupling agent containing epoxy groups on the reinforcing filler.

[0022] Further, relative to 100 parts by weight of the base rubber, the content of the epoxidized reinforcing filler is 40 - 60 parts by weight, and the transesterification catalyst is 0.5 - 3 parts by weight.

[0023] Further, the grafting rate of the epoxy groups in the epoxidized reinforcing filler is 25 - 40%.

[0024] According to the present invention, the epoxidized reinforcing filler is selected from at least one of epoxidized silica, epoxidized montmorillonite, epoxidized kaolin, epoxidized mica, and epoxidized talc powder.

[0025] In the present invention, when the above-mentioned epoxidized reinforcing filler is used, it has the ability to reinforce and form a dynamic crosslinked network, achieving the reinforcing effect of the crosslinked elastomer and avoiding the traditional filler from hindering the formation and rearrangement of dynamic crosslinking bonds, thereby improving the reprocessability of the crosslinked elastomer.

[0026] Further, the epoxidized reinforcing filler is a combination of epoxidized silica and at least one selected from epoxidized montmorillonite, epoxidized kaolin, epoxidized mica, and epoxidized talc powder.

[0027] In the present invention, when the above-mentioned combination of epoxidized reinforcing fillers is used, a hybrid reinforcing network structure can be formed between the epoxidized reinforcing fillers, increasing the contact area between the epoxidized reinforcing filler and the base rubber, and further improving the reprocessability and mechanical properties of the crosslinked elastomer.

[0028] According to the present invention, based on the total weight of the epoxidized reinforcing filler, the content of the epoxidized silica is 70 - 100 wt%.

[0029] In the present invention, when the content of the epoxidized silica meets the above range, the resulting crosslinked elastomer has good mechanical properties and the effect of a faster stress relaxation rate at high temperatures, that is, better reprocessability.

[0030] Further, based on the total weight of the epoxidized reinforcing filler, the content of the epoxidized silica is 80-95 wt%.

[0031] According to the present invention, the epoxidized modifier is a silane coupling agent containing an epoxy group.

[0032] Further, the epoxidized modifier is selected from at least one of γ-(2,3-epoxypropoxy)propyltrimethoxysilane, 3-glycidyletheroxypropyltrimethoxysilane, 3-(2,3-epoxypropyl)propyltriethoxysilane, 3-(2,3-epoxypropyl)propylmethyldiethoxysilane, 3-(2,3-epoxypropyl)propylmethyldimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltriethoxysilane.

[0033] According to the present invention, the content of carboxyl groups in the base rubber is 1-40 wt%.

[0034] In the present invention, when the content of carboxyl groups satisfies the above range, the base rubber has more crosslinkable groups, and the obtained crosslinked elastomer has a good crosslinked network and reprocessability.

[0035] Further, the content of carboxyl groups in the base rubber is 10-40 wt%.

[0036] According to the present invention, the content of acrylonitrile in the base rubber is 18-35 wt%.

[0037] Further, the content of acrylonitrile in the base rubber is 20-35 wt%.

[0038] According to the present invention, the double bond content in the carboxylated hydrogenated nitrile rubber is 0.1 wt%-10 wt%.

[0039] Further, the double bond content in the carboxylated hydrogenated nitrile rubber is 0.5-5 wt%.

[0040] In the present invention, there is no special limitation on the selection of the transesterification catalyst, and it can be a conventional transesterification catalyst in the art. Preferably, the transesterification catalyst is selected from one or a combination of zinc acetate, 1,5,7-triazabicyclo(4.4.0)dec-5-ene (TBD), and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU).

[0041] According to the present invention, the composition further includes an anti-aging agent.

[0042] In the present invention, there is no special limitation on the selection of the anti-aging agent, and it can be a conventional anti-aging agent in the art. Preferably, the anti-aging agent is selected from at least one of N,N'-diphenyl-p-phenylenediamine (anti-aging agent H), N-isopropyl-N'-phenyl-p-phenylenediamine (anti-aging agent 4010NA), 2,2,4-trimethyl-1,2-dihydroquinoline polymer (anti-aging agent RD), 9,9-dimethylacridine (anti-aging agent BLE), 2,2'-methylenebis(4-methyl-6-tert-butylphenol) (anti-aging agent 2246), N-phenyl-2-naphthylamine (anti-aging agent D), and N-(1,3-dimethyl)butyl-N'-phenyl-p-phenylenediamine (anti-aging agent 4020).

[0043] According to the present invention, relative to 100 parts by weight of the base rubber, the anti-aging agent is 0.06 - 4 parts by weight.

[0044] Further, relative to 100 parts by weight of the base rubber, the anti-aging agent is 1 - 3.5 parts by weight.

[0045] According to the present invention, the composition further comprises a plasticizer.

[0046] In the present invention, there is no special limitation on the selection of the plasticizer, and it can be a conventional plasticizer in the art. Preferably, the plasticizer is selected from at least one of naphthenic oil, aromatic oil, paraffin wax, coumarone resin, and petrolatum.

[0047] According to the present invention, relative to 100 parts by weight of the base rubber, the plasticizer is 0.1 - 10 parts by weight.

[0048] Further, relative to 100 parts by weight of the base rubber, the plasticizer is 4 - 8 parts by weight.

[0049] The second aspect of the present invention provides a crosslinked elastomer, wherein the crosslinked elastomer is prepared by mixing and vulcanizing the composition of the above crosslinked elastomer.

[0050] In the present invention, by using a specific content of base rubber and epoxidized reinforcing filler, an interfacial crosslinked network of base rubber - epoxidized reinforcing filler is constructed to form a crosslinked system with dynamic chemical bonds. This crosslinked elastomer has high mechanical properties and, at the same time, excellent reprocessability.

[0051] According to the present invention, the tensile strength of the crosslinked elastomer is greater than or equal to 23 MPa.

[0052] Further, the tensile strength of the crosslinked elastomer is greater than or equal to 26 MPa.

[0053] According to the present invention, the elongation at break of the crosslinked elastomer is 400 - 800%.

[0054] Further, the elongation at break of the crosslinked elastomer is 400-700%.

[0055] According to the present invention, at 140 °C, the time for the crosslinked elastomer to stress-relax to 37% of the original stress is less than or equal to 70 min.

[0056] In the present invention, when the stress relaxation time of the crosslinked elastomer meets the above range, it indicates that the crosslinked elastomer has the characteristic of alleviating thermodynamically driven particle re-aggregation, improving the interfacial stress transfer efficiency, indicating that the crosslinked elastomer has a faster dynamic crosslinked network rearrangement rate, that is, better reprocessability.

[0057] Further, at 140 °C, the time for the crosslinked elastomer to stress-relax to 37% of the original stress is less than or equal to 60 min.

[0058] According to the present invention, at 160 °C, the time for the crosslinked elastomer to stress-relax to 37% of the original stress is less than or equal to 40 min.

[0059] Further, at 160 °C, the time for the crosslinked elastomer to stress-relax to 37% of the original stress is less than or equal to 20 min.

[0060] The third aspect of the present invention provides a method for preparing the above crosslinked elastomer, wherein the method includes: mixing and vulcanizing a base rubber and an epoxidized reinforcing filler to obtain the crosslinked elastomer;

[0061] The grafting rate of epoxy groups in the epoxidized reinforcing filler is 10-50%.

[0062] Further, the grafting rate of epoxy groups in the epoxidized reinforcing filler is 25-40%.

[0063] According to the present invention, the epoxidized reinforcing filler is selected from at least one of epoxidized silica, epoxidized montmorillonite, epoxidized kaolin, epoxidized mica and epoxidized talc powder.

[0064] Further, the epoxidized reinforcing filler is a combination of epoxidized silica and at least one selected from epoxidized montmorillonite, epoxidized kaolin, epoxidized mica and epoxidized talc powder.

[0065] According to the present invention, the epoxidized modifier is a silane coupling agent containing an epoxy group.

[0066] According to the present invention, the epoxidized modifier is selected from at least one of γ-(2,3-epoxypropoxy)propyltrimethoxysilane, 3-glycidyletheroxypropyltrimethoxysilane, 3-(2,3-epoxypropyl)propyltriethoxysilane, 3-(2,3-epoxypropyl)propylmethyldiethoxysilane, 3-(2,3-epoxypropyl)propylmethyldimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltriethoxysilane.

[0067] According to the present invention, based on the total weight of the epoxidized reinforcing filler, the dosage of the epoxidized silica modified is 70-100 wt%.

[0068] Further, based on the total weight of the epoxidized reinforcing filler, the dosage of the epoxidized silica modified is 80-95 wt%.

[0069] In the present invention, there is no special limitation on the source of the epoxidized reinforcing filler, which can be prepared according to the existing preparation methods or obtained through commercial purchase.

[0070] The present invention has no special limitation on the method for modifying the reinforcing filler with the modifier, and conventional modification methods in the art can be adopted. In order to better modify the reinforcing filler, preferably, the modification method includes: after grinding the filler into a uniform powder with a particle size of 10-50 nm, placing the filler and the modifier in a solvent, and stirring and reacting at 60-80 °C for 1.5-2.5 h to obtain the epoxidized reinforcing filler. Preferably, the solvent is ethanol and / or water. Preferably, the mass ratio of the reinforcing filler to the modifier is 1:2-30, preferably 1:5-10.

[0071] According to the present invention, the method includes: mixing and vulcanizing the base rubber, the epoxidized reinforcing filler, the transesterification catalyst, the antioxidant, and the plasticizer to obtain the crosslinked elastomer.

[0072] In the present invention, the selection and dosage of the transesterification catalyst, the antioxidant, and the plasticizer are the same as those in the first aspect, and will not be elaborated herein.

[0073] According to the present invention, the vulcanization temperature is 120-200 °C, the vulcanization pressure is 0.1-25 MPa, and the vulcanization time is 2 min-10 h.

[0074] Further, the vulcanization temperature is 150-190 °C, the vulcanization pressure is 10-20 MPa, and the vulcanization time is 10 min-120 min.

[0075] In the present invention, after the crosslinked elastomer is physically damaged, the damaged crosslinked elastomer is hot-pressed to obtain a secondarily formed crosslinked elastomer. Preferably, the temperature of the hot pressing is 120 - 200 °C, preferably 165 - 190 °C; the pressure is 0.1 - 25 MPa, preferably 10 - 20 MPa; and the time is 2 min - 10 h, preferably 5 min - 4 h.

[0076] The present invention will be described in detail below through examples.

[0077] Carboxylated hydrogenated nitrile rubber: By copolymerizing acrylonitrile, butadiene, and acrylic acid, the obtained carboxylated nitrile rubber is hydrogenated to obtain carboxylated hydrogenated nitrile rubber. The content of carboxyl groups in the carboxylated hydrogenated nitrile rubber is 30 wt%, the content of acrylonitrile is 28 wt%, and the double bond content is 3 wt%.

[0078] Both the tensile strength and the elongation at break are measured by a tensile machine using the method of GB / T 528 - 1998.

[0079] Tensile strength of secondary hot pressing: The crosslinked elastomer is cut into pieces, and then the damaged crosslinked elastomer is re-hot-pressed on a flat vulcanizing machine under a pressure of 15 MPa at 185 °C for 45 min to obtain a flat sample sheet with a thickness of 2 mm.

[0080] The time for the stress relaxation to 37% of the original stress is measured by a rubber processing analyzer with a fixed strain of 100%, and the test temperatures are 140 °C and 160 °C respectively.

[0081] The grafting rate of epoxy groups in the epoxidized reinforcing filler is measured by the thermogravimetric TGA method in a nitrogen atmosphere at a temperature of 40 - 800 °C and a heating rate of 10 °C / min.

[0082] Other raw materials used in the preparation examples, examples, and comparative examples are all commercially available products.

[0083] Preparation Example 1

[0084] Epoxidized reinforcing filler A: Weigh 100 g of unmodified silica, grind it in a ball mill for 60 min, take it out, place it in a solvent containing 100 ml of deionized water and 2500 ml of ethanol, ultrasonicate for 30 min, and add 550 g of silane coupling agent γ-(2,3-epoxypropoxy)propyltrimethoxysilane at 70 °C and react for 12 hours. The product is centrifuged with anhydrous ethanol. Dried for later use to obtain epoxidized silica, and the grafting rate of epoxy groups in the epoxidized silica is 30%.

[0085] Preparation Example 2

[0086] The epoxy-modified reinforcing filler B was prepared according to the method of Preparation Example 1, except that the silica was replaced with montmorillonite to obtain epoxy-modified montmorillonite, and the grafting rate of epoxy groups in the epoxy-modified montmorillonite was 27%.

[0087] Preparation Example 3

[0088] The epoxy-modified reinforcing filler C was prepared according to the method of Preparation Example 1, except that the silica was replaced with kaolin to obtain epoxy-modified kaolin, and the grafting rate of epoxy groups in the epoxy-modified kaolin was 26%.

[0089] Preparation Example 4

[0090] The epoxy-modified reinforcing filler D was prepared according to the method of Preparation Example 1, except that the silica was replaced with mica to obtain epoxy-modified mica, and the grafting rate of epoxy groups in the epoxy-modified mica was 26.5%.

[0091] Preparation Example 5

[0092] The epoxy-modified reinforcing filler E was prepared according to the method of Preparation Example 1, except that the silica was replaced with talcum powder to obtain epoxy-modified talcum powder, and the grafting rate of epoxy groups in the epoxy-modified talcum powder was 26.5%.

[0093] Comparative Preparation Example 1

[0094] The reinforcing filler F was prepared according to the method of Preparation Example 1, except that the silane coupling agent γ-(2,3-epoxypropoxy)propyltrimethoxysilane was replaced with bis-[γ-(triethoxysilyl)propyl]tetrasulfide to prepare a silica modified with a silane coupling agent without epoxy groups. By using the thermogravimetric method, the grafting rate of the bis-[γ-(triethoxysilyl)propyl]tetrasulfide silane coupling agent was measured to be 25.2%.

[0095] Comparative Preparation Example 2

[0096] The epoxy-modified reinforcing filler X was prepared according to the method of Preparation Example 1, except that 100 g of the silane coupling agent γ-(2,3-epoxypropoxy)propyltrimethoxysilane was used to obtain epoxy-modified silica, and the grafting rate of epoxy groups in the epoxy-modified silica was 6%.

[0097] Example 1

[0098] 135 g of carboxylated hydrogenated nitrile rubber was put into a mixer. After 30 s when the torque was stable, 0.7 g of 1,5,7-triazabicyclo(4.4.0)dec-5-ene (TBD), 2.7 g of antioxidant 4020, 4.1 g of naphthenic oil, 61.3 g of epoxy-modified silica and 6.2 g of epoxy-modified montmorillonite were added, and mixing was carried out at 50 °C, and then the sheet was taken out.

[0099] Under the conditions of 15 MPa pressure and 175 °C, a crosslinked elastomer sample sheet with a thickness of 2 mm was molded by compression. The vulcanization time was 30 min. The properties of the crosslinked elastomer are shown in Table 2.

[0100] Examples 2 - 8

[0101] The crosslinked elastomer was prepared according to the method of Example 1, except that the selection and dosage of raw materials are shown in Table 1, and the properties of the crosslinked elastomer are shown in Table 2.

[0102] Comparative Examples 1 - 6

[0103] The crosslinked elastomer was prepared according to the method of Example 1, except that the selection and dosage of raw materials are shown in Table 1, and the properties of the crosslinked elastomer are shown in Table 2.

[0104] Comparative Example 7

[0105] 135 g of carboxyl hydrogenated nitrile rubber was put into a mixer. After 30 s when the torque was stable, 0.7 g of 1,5,7 - triazabicyclo(4.4.0)dec - 5 - ene (TBD), 2.7 g of antioxidant 4020, 4.1 g of naphthenic oil, 42.91 g of white carbon black, 4.526 g of montmorillonite, and 20 g of silane coupling agent γ - (2,3 - epoxypropoxy)propyltrimethoxysilane were added, and mixing was carried out at 50 °C, and then the sheet was taken out.

[0106] Under the conditions of 15 MPa pressure and 175 °C, a crosslinked elastomer sample sheet with a thickness of 2 mm was molded by compression. The vulcanization time was 30 min. The properties of the crosslinked elastomer are shown in Table 2.

[0107] Table 1

[0108]

[0109] Continued Table 1

[0110]

[0111]

[0112] Table 2

[0113]

[0114] It can be seen from the results that, compared with the comparative examples, the crosslinked elastomer of the present invention has the advantages of high tensile strength, high tensile strength in secondary hot - pressing molding, and fast stress relaxation at 140 °C and 160 °C. In Comparative Example 6, since the bis - [γ - (triethoxysilyl)propyl]tetrasulfide silane coupling agent does not contain an epoxy group, the sulfur carrier in the obtained reinforcing filler can only act on a small number of double bonds in the carboxyl hydrogenated nitrile rubber, making it slightly crosslinked. Therefore, the rubber in Comparative Example 6 is an incompletely crosslinked rubber with a short relaxation time.

[0115] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including any other suitable combination of each technical feature. These simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention.

Claims

1. A composition of a crosslinked elastomer, characterized in that, The composition comprises: a base rubber, an epoxidized reinforcing filler, and a transesterification catalyst; Wherein, the base rubber is carboxylated hydrogenated nitrile rubber and / or carboxylated nitrile rubber; Based on 100 parts by weight of the base rubber, the content of the epoxidized reinforcing filler is 10 - 70 parts by weight, and the transesterification catalyst is 0.5 - 10 parts by weight; The grafting rate of the epoxy group in the epoxidized reinforcing filler is 10 - 50%.

2. The composition according to claim 1, wherein Based on 100 parts by weight of the base rubber, the content of the epoxidized reinforcing filler is 40 - 60 parts by weight, and the transesterification catalyst is 0.5 - 3 parts by weight; Preferably, the grafting rate of the epoxy group in the epoxidized reinforcing filler is 25 - 40%.

3. The composition according to claim 1 or 2, wherein The epoxidized reinforcing filler is selected from at least one of epoxidized silica, epoxidized montmorillonite, epoxidized kaolin, epoxidized mica, and epoxidized talc powder, and preferably is a combination of epoxidized silica and at least one selected from epoxidized montmorillonite, epoxidized kaolin, epoxidized mica, and epoxidized talc powder; Preferably, based on the total weight of the epoxidized reinforcing filler, the content of the epoxidized silica is 70 - 100 wt%, preferably 80 - 95 wt%.

4. The composition according to any one of claims 1-3, wherein The epoxidized modifier is a silane coupling agent containing an epoxy group; Preferably, the epoxidized modifier is selected from at least one of γ-(2,3-epoxypropoxy)propyltrimethoxysilane, 3-glycidyletheroxypropyltrimethoxysilane, 3-(2,3-epoxypropyl)propyltriethoxysilane, 3-(2,3-epoxypropyl)propylmethyldiethoxysilane, 3-(2,3-epoxypropyl)propylmethyldimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltriethoxysilane.

5. The composition according to any one of claims 1-4, wherein, The content of the carboxyl group in the base rubber is 1 - 40 wt%, preferably 10 - 40 wt%; Preferably, the content of acrylonitrile in the base rubber is 18 - 35 wt%, preferably 20 - 35 wt%; Preferably, the double bond content in the carboxylated hydrogenated nitrile rubber is 0.1 wt% - 10 wt%, preferably 0.5 - 5 wt%.

6. The composition according to any one of claims 1-5, wherein, The composition further comprises an antioxidant; Preferably, based on 100 parts by weight of the base rubber, the antioxidant is 0.06 - 4 parts by weight, preferably 1 - 3.5 parts by weight; And / or, the composition further comprises a plasticizer; Preferably, based on 100 parts by weight of the base rubber, the plasticizer is 0.1 - 10 parts by weight, preferably 4 - 8 parts by weight.

7. A crosslinked elastomer, characterized in that, The crosslinked elastomer is prepared by mixing and vulcanizing the composition of the crosslinked elastomer according to any one of claims 1 - 6.

8. The crosslinked elastomer according to claim 7, wherein, The tensile strength of the crosslinked elastomer is greater than or equal to 23 MPa, preferably greater than or equal to 26 MPa; Preferably, the elongation at break of the crosslinked elastomer is 400 - 800%, preferably 400 - 700%; Preferably, at 140 °C, the time for the crosslinked elastomer to stress-relax to 37% of the original stress is less than or equal to 70 min, preferably less than or equal to 60 min; Preferably, at 160 °C, the time for the crosslinked elastomer to stress-relax to 37% of the original stress is less than or equal to 40 min, preferably less than or equal to 20 min.

9. A method for preparing the crosslinked elastomer according to claim 7 or 8, characterized in that, The method includes: kneading and vulcanizing a base rubber, an epoxidized reinforcing filler, and a transesterification catalyst to obtain the crosslinked elastomer; The grafting rate of epoxy groups in the epoxidized reinforcing filler is 10 - 50%.

10. The method according to claim 9, wherein, The grafting rate of epoxy groups in the epoxidized reinforcing filler is 25 - 40%; Preferably, the epoxidized reinforcing filler is selected from at least one of epoxidized silica, epoxidized montmorillonite, epoxidized kaolin, epoxidized mica, and epoxidized talc powder, preferably a combination of epoxidized silica and at least one selected from epoxidized montmorillonite, epoxidized kaolin, epoxidized mica, and epoxidized talc powder; Preferably, the epoxidized modifier is a silane coupling agent containing an epoxy group; Preferably, the epoxidized modifier is selected from at least one of γ-(2,3-epoxypropoxy)propyltrimethoxysilane, 3-glycidyletheroxypropyltrimethoxysilane, 3-(2,3-epoxypropyl)propyltriethoxysilane, 3-(2,3-epoxypropyl)propylmethyldiethoxysilane, 3-(2,3-epoxypropyl)propylmethyldimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltriethoxysilane; Preferably, based on the total weight of the epoxidized reinforcing filler, the dosage of epoxidized silica is 70 - 100 wt%, preferably 80 - 95 wt%; Preferably, the vulcanization temperature is 120 - 200 °C, preferably 150 - 190 °C; Preferably, the vulcanization pressure is 0.1 - 25 MPa, preferably 10 - 20 MPa; Preferably, the vulcanization time is 2 min - 10 h, preferably 10 min - 120 min.

11. The method according to claim 9 or 10, wherein The method includes: kneading and vulcanizing a base rubber, the epoxidized reinforcing filler, a transesterification catalyst, an antioxidant, and a plasticizer to obtain the crosslinked elastomer.

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