High-temperature-resistant rubber and preparation method thereof

Abstract

The invention relates to the technical field of rubber, in particular to high-temperature-resistant rubber and a preparation method thereof. The high-temperature-resistant rubber is prepared from the following raw materials: chloroprene rubber, organic silicon modified chloroprene rubber, an anti-aging agent, zinc oxide, magnesium oxide, sulfur, stearic acid, paraffin, a plasticizer and an accelerant, the organic silicon modified chloroprene rubber is obtained by carrying out surface modification on chloroprene rubber through hydroxyethyl methylacrylate and 3-methoxysilane propyl acrylate and then cross-linking dimethyl dimethoxy silane and tetraethyl orthosilicate. The high-temperature-resistant rubber prepared by the invention has excellent mechanical properties and high-temperature resistance.

Description

Technical Field

[0001] The invention relates to the technical field of rubber, and in particular to a high temperature resistant rubber and a preparation method thereof. Background Art

[0002] Rubber materials are widely used in industries such as industry, automobiles, aerospace, etc. due to their excellent elasticity, wear resistance and fatigue resistance. They are an indispensable and important material in modern industry. However, in high temperature environments, the mechanical properties and aging resistance of traditional rubber materials tend to decrease significantly, resulting in a shortened service life, which limits their application under high temperature conditions. For example, in high temperature environments, rubber materials are prone to thermal oxidation aging, which is manifested as a significant decrease in mechanical properties such as tensile strength and elongation at break, and even cracking and hardening, which seriously affects their use effect and safety. Therefore, the development of rubber materials with excellent high temperature resistance and thermal aging performance has become an important research direction in the rubber field.

[0003] Chloroprene rubber (CR) is a synthetic rubber with excellent performance. It is widely used in seals, hoses, transmission belts, cable sheaths and other fields because of its good weather resistance, oil resistance, heat resistance and flame retardancy. Compared with other rubbers, chloroprene rubber has better high temperature resistance to a certain extent, but traditional vulcanized chloroprene rubber is still prone to thermal oxidation aging under long-term high temperature environment, resulting in a significant decrease in its mechanical properties. For example, under high temperature conditions, the molecular chain of chloroprene rubber is easy to break or the cross-linking structure changes, resulting in a decrease in the tensile strength and elongation at break of the material, and a decrease in elasticity and flexibility, making it difficult to meet the use requirements of high temperature conditions. Therefore, how to further improve the high temperature resistance and thermal aging performance of chloroprene rubber has become the focus of current research. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a high temperature resistant rubber and a preparation method thereof, so as to solve the problem that under high temperature conditions, the molecular chain of chloroprene rubber is easily broken or the cross-linking structure changes, resulting in a decrease in the tensile strength and elongation at break of the material.

[0005] Based on the above purpose, the present invention provides a high temperature resistant rubber, which is prepared from the following raw materials in parts by weight: 60-80 parts of chloroprene rubber, 20-40 parts of organosilicon modified chloroprene rubber, 1-2 parts of antioxidant, 3-5 parts of zinc oxide, 4-6 parts of magnesium oxide, 0.5-1.5 parts of sulfur, 1-3 parts of stearic acid, 4-6 parts of paraffin, 1-3 parts of plasticizer and 2-4 parts of accelerator;

[0006] Furthermore, the preparation method of the organosilicon-modified chloroprene rubber is as follows:

[0007] S11: adding chloroprene rubber to a mixed solution of toluene and ethyl acetate, stirring for 20-40 minutes, then heating to 75-85° C., adding benzoyl peroxide, and then dripping hydroxyethyl methacrylate and 3-methoxysilane propyl acrylate, the dripping is completed within 3-8 minutes, and the reaction is continued for 3-5 hours, cooling, and vacuum drying to obtain surface-modified chloroprene rubber;

[0008] S12: adding the surface modified chloroprene rubber to a mixed solution of deionized water and anhydrous ethanol, stirring for 20-40 minutes, then adding dimethyldimethoxysilane and tetraethyl orthosilicate, heating to 55-65° C., continuing stirring for 5-7 hours, and vacuum drying to obtain the silicone modified chloroprene rubber;

[0009] Preferably, the weight ratio of chloroprene rubber, toluene, ethyl acetate, benzoyl peroxide, hydroxyethyl methacrylate and 3-methoxysilane propyl acrylate in S11 is 15-25:70-90:100-140:0.5-1.5:4-6:12-18;

[0010] Preferably, the weight ratio of the surface modified chloroprene rubber, deionized water, anhydrous ethanol, dimethyldimethoxysilane and tetraethyl orthosilicate in S12 is 15-25:20-40:80-120:15-25:2-8.

[0011] Preferably, the antioxidant is one of antioxidant ODA and antioxidant RD, or a mixture of the two.

[0012] Preferably, the plasticizer is plasticizer DOS.

[0013] Preferably, the accelerator is one of accelerator DTDM and accelerator NA-22 or a mixture of the two.

[0014] Furthermore, the present invention also provides a method for preparing high temperature resistant rubber, comprising the following steps:

[0015] S21: putting chloroprene rubber and organosilicon-modified chloroprene rubber into a mixer and plasticating them on a roll for 2-4 minutes, then sequentially adding an antioxidant, zinc oxide, magnesium oxide, sulfur, stearic acid, paraffin, a plasticizer and an accelerator for mixing, and then packing and thinning the sheets to obtain a mixed film;

[0016] S22: vulcanize the mixed rubber sheet after leaving it for 20-30 hours to obtain high temperature resistant rubber.

[0017] Preferably, the vulcanization temperature is 155-165°C, the pressure is 35-45MPa, and the time is 20-30min. Beneficial effects of the present invention:

[0018] After heat aging at 70°C for 72 hours, the tensile strength of the high-temperature resistant rubber prepared by the present invention increases, indicating that secondary vulcanization occurs during the heat aging process, increasing the crosslinking density, thereby improving the mechanical properties; after heat aging at 100°C for 72 hours, the tensile strength only shows a slight decrease, indicating that it has excellent high-temperature aging resistance.

[0019] The present invention can effectively improve the mechanical properties and high temperature aging resistance of rubber by modifying the surface of chloroprene rubber with hydroxyethyl methacrylate. This is because hydroxyethyl methacrylate changes the hydrophilicity of the surface of chloroprene rubber, promotes the crosslinking of organosilicon on the surface, thereby improving the comprehensive performance of rubber. In addition, the 3-methoxysilane propyl acrylate modified on the surface of chloroprene rubber significantly improves the mechanical properties and high temperature aging resistance of rubber, and the crosslinking sites provided by it can form an organosilicon network with dimethyldimethoxysilane and tetraethyl orthosilicate, further enhancing the crosslinking density and stability of rubber. More importantly, the synergistic effect of hydroxyethyl methacrylate and 3-methoxysilane propyl acrylate significantly improves the mechanical properties and high temperature aging resistance of rubber.

[0020] The present invention forms a loose organic silicon network on the surface of chloroprene rubber through the synergistic effect of dimethyldimethoxysilane and tetraethyl orthosilicate, which helps the rubber to achieve more efficient cross-linking during the mixing process, thereby further improving its mechanical properties and high temperature aging resistance. These combined effects make the high temperature resistant rubber of the present invention show significant advantages in mechanical properties and high temperature aging resistance. DETAILED DESCRIPTION

[0021] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0022] The chloroprene rubber used in the specific implementation manner of the present invention is produced by NEC Corporation and its model is DCR-36.

[0023] Embodiment 1:

[0024] (1) 15 g of chloroprene rubber was added to a mixed solution of 70 g of toluene and 100 g of ethyl acetate, stirred for 20 min, then heated to 75° C., 0.5 g of benzoyl peroxide was added, and then 4 g of hydroxyethyl methacrylate and 12 g of 3-methoxysilane propyl acrylate were added dropwise within 3 min, the reaction was continued for 3 h, the temperature was lowered, and vacuum dried to obtain a surface-modified chloroprene rubber;

[0025] (2) adding 15 g of surface modified chloroprene rubber to a mixed solution of 20 g of deionized water and 80 g of anhydrous ethanol, stirring for 20 min, then adding 15 g of dimethyldimethoxysilane and 2 g of tetraethyl orthosilicate, heating to 55° C., stirring for 5 h, and vacuum drying to obtain silicone modified chloroprene rubber;

[0026] (3) 80 g of chloroprene rubber and 20 g of organosilicon-modified chloroprene rubber were put into a mixer and rolled for 2 min, and then 1 g of antioxidant RD, 3 g of zinc oxide, 4 g of magnesium oxide, 0.5 g of sulfur, 1 g of stearic acid, 4 g of paraffin wax, 1 g of plasticizer DOS and 2 g of accelerator DTDM were added in sequence for mixing, and the rubber was continuously poured during the mixing process to ensure uniform mixing, and then the mixed film was packaged, thinned and discharged to obtain a mixed film;

[0027] (4) The mixed rubber sheet was left to stand for 20 hours and then vulcanized at a vulcanization temperature of 155°C, a vulcanization pressure of 35 MPa, and a vulcanization time of 20 minutes to obtain a high temperature resistant rubber.

[0028] Embodiment 2:

[0029] (1) Add 20 g of chloroprene rubber to a mixed solution of 80 g of toluene and 120 g of ethyl acetate, stir for 30 min, then heat to 80° C., add 1 g of benzoyl peroxide, then dropwise add 5 g of hydroxyethyl methacrylate and 15 g of 3-methoxysilane propyl acrylate, and complete the dropwise addition within 5 min. Continue the reaction for 4 h, cool, and vacuum dry to obtain a surface-modified chloroprene rubber;

[0030] (2) adding 20 g of surface modified chloroprene rubber to a mixed solution of 30 g of deionized water and 100 g of anhydrous ethanol, stirring for 30 min, then adding 20 g of dimethyldimethoxysilane and 5 g of tetraethyl orthosilicate, heating to 60° C., stirring for 6 h, and vacuum drying to obtain silicone modified chloroprene rubber;

[0031] (3) 70 g of chloroprene rubber and 30 g of organosilicon-modified chloroprene rubber were put into a mixer and rolled for 3 min, and then 0.5 g of antioxidant ODA, 1 g of antioxidant RD, 4 g of zinc oxide, 5 g of magnesium oxide, 1 g of sulfur, 2 g of stearic acid, 5 g of paraffin wax, 2 g of plasticizer DOS, 2 g of accelerator DTDM and 1 g of accelerator NA-22 were added in sequence for mixing, and the rubber was continuously poured during the mixing process to ensure uniform mixing, and then the mixed film was packaged, thinned and discharged to obtain a mixed film;

[0032] (4) The mixed rubber sheet was left to stand for 24 hours and then vulcanized at a vulcanization temperature of 160°C, a vulcanization pressure of 40 MPa, and a vulcanization time of 25 minutes to obtain a high temperature resistant rubber.

[0033] Embodiment 3:

[0034] (1) Add 25 g of chloroprene rubber to a mixed solution of 90 g of toluene and 140 g of ethyl acetate, stir for 40 min, then heat to 85° C., add 1.5 g of benzoyl peroxide, then dropwise add 6 g of hydroxyethyl methacrylate and 18 g of 3-methoxysilane propyl acrylate, and complete the dropwise addition within 8 min. Continue the reaction for 5 h, cool, and vacuum dry to obtain a surface-modified chloroprene rubber;

[0035] (2) adding 25 g of surface modified chloroprene rubber to a mixed solution of 40 g of deionized water and 120 g of anhydrous ethanol, stirring for 40 min, then adding 25 g of dimethyldimethoxysilane and 8 g of tetraethyl orthosilicate, heating to 65° C., stirring for 7 h, and vacuum drying to obtain silicone modified chloroprene rubber;

[0036] (3) 60 g of chloroprene rubber and 40 g of organosilicon-modified chloroprene rubber were put into a mixer and rolled for 3 min, and then 2 g of antioxidant ODA, 5 g of zinc oxide, 6 g of magnesium oxide, 1.5 g of sulfur, 3 g of stearic acid, 6 g of paraffin, 3 g of plasticizer DOS, 2 g of accelerator DTDM and 2 g of accelerator NA-22 were added in sequence for mixing, and the rubber was continuously poured during the mixing process to ensure uniform mixing, and then the mixed film was packaged, thinned and discharged to obtain a mixed film;

[0037] (4) The mixed rubber sheet was left to stand for 30 hours and then vulcanized at a vulcanization temperature of 165°C, a vulcanization pressure of 45 MPa, and a vulcanization time of 30 minutes to obtain a high temperature resistant rubber.

[0038] Comparative Example 1:

[0039] The difference between Comparative Example 1 and Example 2 is that: hydroxyethyl methacrylate is not added in step (1);

[0040] The specific steps are as follows:

[0041] (1) Add 20 g of chloroprene rubber to a mixed solution of 80 g of toluene and 120 g of ethyl acetate, stir for 30 min, then heat to 80° C., add 1 g of benzoyl peroxide, and then dropwise add 20 g of 3-methoxysilane propyl acrylate. The dropwise addition is completed within 5 min, and the reaction is continued for 4 h. The temperature is lowered and vacuum dried to obtain a surface-modified chloroprene rubber.

[0042] (2) adding 20 g of surface modified chloroprene rubber to a mixed solution of 30 g of deionized water and 100 g of anhydrous ethanol, stirring for 30 min, then adding 20 g of dimethyldimethoxysilane and 5 g of tetraethyl orthosilicate, heating to 60° C., stirring for 6 h, and vacuum drying to obtain silicone modified chloroprene rubber;

[0043] (3) 70 g of chloroprene rubber and 30 g of organosilicon-modified chloroprene rubber were put into a mixer and rolled for 3 min, and then 0.5 g of antioxidant ODA, 1 g of antioxidant RD, 4 g of zinc oxide, 5 g of magnesium oxide, 1 g of sulfur, 2 g of stearic acid, 5 g of paraffin wax, 2 g of plasticizer DOS, 2 g of accelerator DTDM and 1 g of accelerator NA-22 were added in sequence for mixing, and the rubber was continuously poured during the mixing process to ensure uniform mixing, and then the mixed film was packaged, thinned and discharged to obtain a mixed film;

[0044] (4) The mixed rubber sheet was left to stand for 24 hours and then vulcanized at a vulcanization temperature of 160° C., a vulcanization pressure of 40 MPa, and a vulcanization time of 25 min to obtain rubber.

[0045] Comparative Example 2:

[0046] The difference between Comparative Example 2 and Example 2 is that: 3-methoxysilane propyl acrylate is not added in step (1);

[0047] The specific steps are as follows:

[0048] (1) Add 20 g of chloroprene rubber to a mixed solution of 80 g of toluene and 120 g of ethyl acetate, stir for 30 min, then heat to 80° C., add 1 g of benzoyl peroxide, and then dropwise add 20 g of hydroxyethyl methacrylate within 5 min, continue the reaction for 4 h, cool, and vacuum dry to obtain a surface-modified chloroprene rubber;

[0049] (2) adding 20 g of surface modified chloroprene rubber to a mixed solution of 30 g of deionized water and 100 g of anhydrous ethanol, stirring for 30 min, then adding 20 g of dimethyldimethoxysilane and 5 g of tetraethyl orthosilicate, heating to 60° C., stirring for 6 h, and vacuum drying to obtain silicone modified chloroprene rubber;

[0050] (3) 70 g of chloroprene rubber and 30 g of organosilicon-modified chloroprene rubber were put into a mixer and rolled for 3 min, and then 0.5 g of antioxidant ODA, 1 g of antioxidant RD, 4 g of zinc oxide, 5 g of magnesium oxide, 1 g of sulfur, 2 g of stearic acid, 5 g of paraffin wax, 2 g of plasticizer DOS, 2 g of accelerator DTDM and 1 g of accelerator NA-22 were added in sequence for mixing, and the rubber was continuously poured during the mixing process to ensure uniform mixing, and then the mixed film was packaged, thinned and discharged to obtain a mixed film;

[0051] (4) The mixed rubber sheet was left to stand for 24 hours and then vulcanized at a vulcanization temperature of 160° C., a vulcanization pressure of 40 MPa, and a vulcanization time of 25 min to obtain rubber.

[0052] Comparative Example 3:

[0053] The difference between Comparative Example 3 and Example 2 is that the surface-modified chloroprene rubber in step (2) is replaced by chloroprene rubber;

[0054] The specific steps are as follows:

[0055] (1) Add 20 g of chloroprene rubber to a mixed solution of 30 g of deionized water and 100 g of anhydrous ethanol, stir for 30 min, then add 20 g of dimethyldimethoxysilane and 5 g of tetraethyl orthosilicate, heat to 60° C., continue stirring for 6 h, and vacuum dry to obtain silicone-modified chloroprene rubber;

[0056] (2) 70 g of chloroprene rubber and 30 g of organosilicon-modified chloroprene rubber were put into a mixer and rolled for 3 min, and then 0.5 g of antioxidant ODA, 1 g of antioxidant RD, 4 g of zinc oxide, 5 g of magnesium oxide, 1 g of sulfur, 2 g of stearic acid, 5 g of paraffin wax, 2 g of plasticizer DOS, 2 g of accelerator DTDM and 1 g of accelerator NA-22 were added in sequence for mixing, and the rubber was continuously poured during the mixing process to ensure uniform mixing, and then the mixed film was packaged, thinned and discharged to obtain a mixed film;

[0057] (3) The mixed rubber sheet was left to stand for 24 hours and then vulcanized at a vulcanization temperature of 160° C., a vulcanization pressure of 40 MPa, and a vulcanization time of 25 min to obtain rubber.

[0058] Comparative Example 4:

[0059] The difference between Comparative Example 4 and Example 2 is that: dimethyldimethoxysilane is not added in step (2);

[0060] The specific steps are as follows:

[0061] (1) Add 20 g of chloroprene rubber to a mixed solution of 80 g of toluene and 120 g of ethyl acetate, stir for 30 min, then heat to 80° C., add 1 g of benzoyl peroxide, then dropwise add 5 g of hydroxyethyl methacrylate and 15 g of 3-methoxysilane propyl acrylate, and complete the dropwise addition within 5 min. Continue the reaction for 4 h, cool, and vacuum dry to obtain a surface-modified chloroprene rubber;

[0062] (2) adding 20 g of surface modified chloroprene rubber to a mixed solution of 30 g of deionized water and 100 g of anhydrous ethanol, stirring for 30 min, then adding 25 g of tetraethyl orthosilicate, heating to 60° C., stirring for 6 h, and vacuum drying to obtain silicone modified chloroprene rubber;

[0063] (3) 70 g of chloroprene rubber and 30 g of organosilicon-modified chloroprene rubber were put into a mixer and rolled for 3 min, and then 0.5 g of antioxidant ODA, 1 g of antioxidant RD, 4 g of zinc oxide, 5 g of magnesium oxide, 1 g of sulfur, 2 g of stearic acid, 5 g of paraffin wax, 2 g of plasticizer DOS, 2 g of accelerator DTDM and 1 g of accelerator NA-22 were added in sequence for mixing, and the rubber was continuously poured during the mixing process to ensure uniform mixing, and then the mixed film was packaged, thinned and discharged to obtain a mixed film;

[0064] (4) The mixed rubber sheet was left to stand for 24 hours and then vulcanized at a vulcanization temperature of 160° C., a vulcanization pressure of 40 MPa, and a vulcanization time of 25 min to obtain rubber.

[0065] Comparative Example 5:

[0066] The difference between Comparative Example 5 and Example 2 is that: tetraethyl orthosilicate is not added in step (2);

[0067] The specific steps are as follows:

[0068] (1) Add 20 g of chloroprene rubber to a mixed solution of 80 g of toluene and 120 g of ethyl acetate, stir for 30 min, then heat to 80° C., add 1 g of benzoyl peroxide, then dropwise add 5 g of hydroxyethyl methacrylate and 15 g of 3-methoxysilane propyl acrylate, and complete the dropwise addition within 5 min. Continue the reaction for 4 h, cool, and vacuum dry to obtain a surface-modified chloroprene rubber;

[0069] (2) adding 20 g of surface modified chloroprene rubber to a mixed solution of 30 g of deionized water and 100 g of anhydrous ethanol, stirring for 30 min, adding 25 g of dimethyldimethoxysilane, heating to 60° C., stirring for 6 h, and vacuum drying to obtain silicone-modified chloroprene rubber;

[0070] (3) 70 g of chloroprene rubber and 30 g of organosilicon-modified chloroprene rubber were put into a mixer and rolled for 3 min, and then 0.5 g of antioxidant ODA, 1 g of antioxidant RD, 4 g of zinc oxide, 5 g of magnesium oxide, 1 g of sulfur, 2 g of stearic acid, 5 g of paraffin wax, 2 g of plasticizer DOS, 2 g of accelerator DTDM and 1 g of accelerator NA-22 were added in sequence for mixing, and the rubber was continuously poured during the mixing process to ensure uniform mixing, and then the mixed film was packaged, thinned and discharged to obtain a mixed film;

[0071] (4) The mixed rubber sheet was left to stand for 24 hours and then vulcanized at a vulcanization temperature of 160°C, a vulcanization pressure of 40 MPa, and a vulcanization time of 25 minutes to obtain a high temperature resistant rubber.

[0072] Comparative Example 6:

[0073] The difference between Comparative Example 6 and Example 2 is that the organosilicon-modified chloroprene rubber in step (3) is replaced by chloroprene rubber;

[0074] The specific steps are as follows:

[0075] (1) Chloroprene rubber and 30 g of organosilicon-modified chloroprene rubber are put into a mixer and rolled for 3 min, and then 0.5 g of antioxidant ODA, 1 g of antioxidant RD, 4 g of zinc oxide, 5 g of magnesium oxide, 1 g of sulfur, 2 g of stearic acid, 5 g of paraffin wax, 2 g of plasticizer DOS, 2 g of accelerator DTDM and 1 g of accelerator NA-22 are added in sequence for mixing, and the rubber is continuously poured during the mixing process to ensure uniform mixing, and then the mixed film is packaged, thinned and discharged to obtain a mixed film;

[0076] (2) The mixed rubber sheet was left for 24 hours and then vulcanized at a vulcanization temperature of 160°C, a vulcanization pressure of 40 MPa, and a vulcanization time of 25 minutes to obtain a high temperature resistant rubber.

[0077] Performance Test:

[0078] Mechanical properties test: tensile strength and elongation at break are tested according to GB / T528-1998, and the tensile speed is 500mm / min;

[0079] High temperature aging test: According to GB / T 528-2009, the samples were placed at 70℃ and 100℃ for 72h, and then taken out after the predetermined time. They were cooled at room temperature for 24h to achieve thermal equilibrium before testing. Finally, the mechanical properties were tested.

[0080] Table 1 Performance test results

[0081]

[0082] Data Analysis:

[0083] It can be seen from the data of Examples 1-3 and Comparative Example 6 in Table 1 that, relative to conventional vulcanized chloroprene rubber, the high temperature resistant rubber prepared by the present invention has higher tensile strength and elongation at break. Most importantly, after heat aging at 70°C for 72 hours, the tensile strength increases, which may be due to the secondary vulcanization occurring during the heat aging process, thereby increasing the crosslinking density. After heat aging at 100°C for 72 hours, the tensile strength shows a slight decrease, indicating that it has excellent high temperature aging resistance.

[0084] It can be seen from the data of Example 2 and Comparative Example 1 in Table 1 that hydroxyethyl methacrylate modified on the surface of chloroprene rubber can effectively improve the mechanical properties of high temperature resistant rubber, and can further improve the high temperature aging resistance. This is mainly because hydroxyethyl methacrylate changes the hydrophilicity of the surface of chloroprene rubber and promotes the cross-linking of silicone on the surface, thereby improving the performance of the high temperature resistant rubber.

[0085] It can be seen from the data of Example 2 and Comparative Example 2 in Table 1 that 3-methoxysilane propyl acrylate modified on the surface of chloroprene rubber can significantly improve the mechanical properties of high temperature resistant rubber, and has a significant effect on high temperature aging resistance. This is mainly because 3-methoxysilane propyl acrylate provides cross-linking sites and can form a cross-linked silicone network with dimethyldimethoxysilane and tetraethyl orthosilicate.

[0086] It can be seen from the data of Example 2 and Comparative Example 3 in Table 1 that the hydroxyethyl methacrylate and 3-methoxysilane propyl acrylate used to modify the surface of chloroprene rubber synergistically improve the mechanical properties and high temperature aging resistance of the rubber.

[0087] It can be seen from the data of Example 2 and Comparative Examples 4-5 in Table 1 that dimethyldimethoxysilane and tetraethyl orthosilicate synergistically improve the mechanical properties and high temperature aging resistance of the rubber. This is mainly because dimethyldimethoxysilane and tetraethyl orthosilicate form a loose silicone network on the surface of chloroprene rubber, which helps the chloroprene rubber to crosslink during the mixing process.

[0088] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention is limited to these examples. Under the concept of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity.

Claims

1. A high temperature resistant rubber, characterized in that: The composition is prepared from the following raw materials by weight: 60-80 parts of chloroprene rubber, 20-40 parts of organosilicon-modified chloroprene rubber, 1-2 parts of antioxidant, 3-5 parts of zinc oxide, 4-6 parts of magnesium oxide, 0.5-1.5 parts of sulfur, 1-3 parts of stearic acid, 4-6 parts of paraffin wax, 1-3 parts of plasticizer and 2-4 parts of accelerator; The preparation method of the organosilicon modified chloroprene rubber is as follows: S11: adding chloroprene rubber to a mixed solution of toluene and ethyl acetate, stirring for 20-40 minutes, then heating to 75-85° C., adding benzoyl peroxide, and then dripping hydroxyethyl methacrylate and 3-methoxysilane propyl acrylate, the dripping is completed within 3-8 minutes, and the reaction is continued for 3-5 hours, cooling, and vacuum drying to obtain surface-modified chloroprene rubber; S12: adding the surface modified chloroprene rubber to a mixed solution of deionized water and anhydrous ethanol, stirring for 20-40 minutes, then adding dimethyldimethoxysilane and tetraethyl orthosilicate, heating to 55-65° C., continuing stirring for 5-7 hours, and vacuum drying to obtain the silicone modified chloroprene rubber; The weight ratio of chloroprene rubber, toluene, ethyl acetate, benzoyl peroxide, hydroxyethyl methacrylate and 3-methoxysilane propyl acrylate in S11 is 15-25:70-90:100-140:0.5-1.5:4-6:12-18; The weight ratio of the surface modified chloroprene rubber, deionized water, anhydrous ethanol, dimethyldimethoxysilane and tetraethyl orthosilicate in S12 is 15-25:20-40:80-120:15-25:2-8.

2. The high temperature resistant rubber according to claim 1, characterized in that: The antioxidant is one of antioxidant ODA and antioxidant RD or a mixture of the two.

3. The high temperature resistant rubber according to claim 1, characterized in that: The plasticizer is plasticizer DOS.

4. The high temperature resistant rubber according to claim 1, characterized in that: The accelerator is one of accelerator DTDM and accelerator NA-22 or a mixture of the two.

5. A method for preparing the high temperature resistant rubber according to any one of claims 1 to 4, characterized in that: The following steps are involved: S21: putting chloroprene rubber and organosilicon-modified chloroprene rubber into a mixer and plasticating them on a roll for 2-4 minutes, then sequentially adding an antioxidant, zinc oxide, magnesium oxide, sulfur, stearic acid, paraffin, a plasticizer and an accelerator for mixing, and then packing and thinning the sheets to obtain a mixed film; S22: vulcanize the mixed rubber sheet after standing for 20-30 hours to obtain high temperature resistant rubber.

6. The method for preparing high temperature resistant rubber according to claim 5, characterized in that: The vulcanization temperature is 155-165° C., the pressure is 35-45 MPa, and the time is 20-30 min.

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