Odorless transparent platinum vulcanized EPDM rubber and preparation method thereof

Abstract

The invention relates to the technical field of rubber materials, and particularly discloses odorless transparent platinum vulcanized EPDM rubber and a preparation method thereof. The odorless transparent platinum vulcanized EPDM rubber is prepared from the following raw materials in parts by weight: 100 to 115 parts of EPDM particles, 20 to 60 parts of white carbon black, 2 to 10 parts of hydroxyl silicone oil, 0 to 20 parts of liquid EPDM, 1 to 15 parts of hydrogen-containing silicone oil and 1.2 to 2.5 parts of platinum vulcanizing agent. The odorless transparent platinum vulcanized EPDM rubber disclosed by the invention is odorless and transparent, has excellent mechanical properties and chemical stability, can be applied to the food industry, and can meet the safety requirements of occasions needing to be in direct contact with food or in close contact with a food environment.

Description

Technical Field

[0001] The present application relates to the technical field of rubber materials, and more specifically, to an odorless and transparent platinum-vulcanized EPDM rubber and a preparation method thereof. Background Art

[0002] EPDM (ethylene propylene diene monomer) is a synthetic rubber with excellent performance. Its molecular structure contains ethylene, propylene and diene monomers, which gives it excellent weather resistance, chemical resistance, heat resistance, electrical insulation and flexibility. It is widely used in many fields such as construction, sports venues, automotive industry, and power industry.

[0003] However, due to fillers, rubber oil, vulcanization method, raw rubber and other ingredients in the formula, EPDM rubber will produce by-products with pungent odor during the traditional sulfur vulcanization and peroxide vulcanization processes, which makes EPDM usually emit a pungent odor during use. These by-products not only affect the user experience of EPDM, but may also cause potential harm to the environment and human health, greatly limiting the application of EPDM in certain specific fields, especially the food industry. It is unacceptable for applications that require direct contact with food or close contact with the food environment.

[0004] In order to solve the problem of EPDM's pungent odor, the industry mostly adopts the following methods: using metallocene-catalyzed EPDM to reduce odor; filling colorless paraffin oil to reduce volatile components; using carbon black and inorganic fillers made from natural gas to reduce the release of harmful gases; changing the vulcanization system, not using peroxide vulcanizers and sulfur vulcanization, and using comprehensive accelerator vulcanization; and performing secondary vulcanization.

[0005] With respect to the above-mentioned related technologies, the inventors found that these methods can only reduce the odor of EPDM to a certain extent, the problem of the vulcanization system cannot be solved, there will still be a pungent odor, and the odor problem of EPDM cannot be fundamentally solved. Summary of the invention

[0006] In order to improve the pungent smell of EPDM rubber products and enhance the application performance of EPDM rubber products, the present application provides an odorless and transparent platinum-vulcanized EPDM rubber.

[0007] In the first aspect, the present application provides an odorless, transparent platinum-vulcanized EPDM rubber, which adopts the following technical solution: an odorless, transparent platinum-vulcanized EPDM rubber, wherein the raw materials include, by weight, 100-115 parts of EPDM particles, 20-60 parts of white carbon black, 2-10 parts of hydroxy silicone oil, 0-20 parts of liquid EPDM, 1-15 parts of hydrogen-containing silicone oil and 1.2-2.5 parts of platinum vulcanizer.

[0008] By adopting the above technical solution, using a platinum vulcanizer, and obtaining EPDM rubber through a platinum vulcanization system, compared with traditional sulfur vulcanization or peroxide vulcanization, the product EPDM rubber can be completely odorless and has very good transparency.

[0009] This is because, during the vulcanization process, platinum vulcanizer mainly acts as a catalyst to promote the cross-linking reaction of EPDM. It promotes cross-linking by catalyzing the reaction between double bonds or other active points on the EPDM molecular chain to form a uniform and dense cross-linked network. Unlike sulfur, it will not remain in the rubber as part of the cross-linking bond. It has higher catalytic efficiency and selectivity, can more effectively control the progress of the vulcanization reaction, reduce the formation of by-products and the residue of harmful substances, especially reduce the generation of irritating odorous gases such as hydrogen sulfide and sulfur dioxide, thereby achieving odorless EPDM rubber products, improving application safety, giving EPDM rubber higher transparency, high temperature resistance and chemical stability, while maintaining excellent mechanical properties.

[0010] Hydroxy silicone oil and hydrogen silicone oil are odorless. The active hydrogen in hydroxy silicone oil and the silicon-hydrogen bond (Si-H) in hydrogen silicone oil can serve as active points for vulcanization reactions, reacting with platinum vulcanizers to generate active centers, thereby improving crosslinking efficiency, promoting the complete reaction of platinum vulcanizers, preventing the occurrence of other side reactions that may produce odor, and further promoting the stability of the crosslinking network between EPDM molecular chains, which helps to improve the mechanical properties of EPDM rubber.

[0011] Optionally, the platinum vulcanizing agent includes 0.4-1 parts of platinum vulcanizing agent A and 0.8-1.5 parts of platinum vulcanizing agent B in parts by weight.

[0012] By adopting the above technical solution and accurately controlling the dosage and addition time of platinum vulcanizing agent A and agent B, it is possible to more accurately control the start and progress of the vulcanization reaction, achieve precise control of the vulcanization process, promote the complete progress of the vulcanization reaction, and reduce the generation of harmful substances.

[0013] Optionally, the EPDM particles are any one or a combination of two of Mitsui metallocene catalyst VNB-EPT type PX-008M and PX-009M, based on parts by weight.

[0014] By adopting the above technical solution, metallocene-catalyzed EPDM reduces impurities and residues in the polymer, usually has higher purity, more uniform molecular structure, is easier to react with platinum vulcanizer, and can effectively reduce unnecessary side reactions, thereby ensuring that the product is odorless.

[0015] Optionally, the hydrogen content of the hydrogen-containing silicone oil is 0.07-1.6% by weight.

[0016] Optionally, the white carbon black is fumed white carbon black, and the specific surface area is (120-310) ± 20m 2 / g.

[0017] Optionally, the viscosity of the hydroxy silicone oil is 27 mm 2 / S, the hydroxyl content is 8%.

[0018] In a second aspect, the present application provides a method for preparing odorless and transparent platinum-vulcanized EPDM rubber, using the following technical solution: A method for preparing odorless and transparent platinum-vulcanized EPDM rubber comprises the following steps: S1: EPDM particles are subjected to open milling, rolled, and then white carbon black, hydroxy silicone oil, liquid EPDM and hydrogen-containing silicone oil are added, and the particles are uniformly dispersed and then produced into sheets to obtain an initial EPDM film; S2: baking the initial EPDM film at 120-130° C. for 20-40 min, and naturally cooling to obtain a pretreated EPDM film; S3: first add platinum vulcanization agent B to the pretreated EPDM film, mix evenly, then add platinum vulcanization agent A, mix evenly, and then produce a sheet to obtain a prefabricated EPDM film; S4: Place the prefabricated EPDM film in the mold at 170-180°C and vulcanize for 15-20 minutes.

[0019] By adopting the above technical scheme, the raw materials of the present application are all low-odor or odorless raw materials, and a platinum vulcanization system is adopted, abandoning the traditional sulfur vulcanization and peroxide vulcanization methods, thereby ensuring that the EPDM rubber product is clean, odorless and transparent.

[0020] Under the regulation of the raw material formula and vulcanization system process steps of the present application, it helps to ensure that the degree of vulcanization of EPDM rubber products is moderate, neither excessive vulcanization resulting in performance degradation nor insufficient vulcanization resulting in insufficient strength, thereby ensuring that the product has excellent mechanical properties.

[0021] In a third aspect, the present application provides an application of odorless, transparent platinum-vulcanized EPDM rubber in the preparation of food contact materials.

[0022] Optionally, the food contact materials include conveying hoses and pipes used in food processing, food conveyor belts, food storage containers, food packaging materials and food rubber gloves.

[0023] In summary, this application has the following beneficial effects: 1. This application abandons the traditional sulfur vulcanization and peroxide vulcanization methods, and adopts the platinum vulcanization method to promote the cross-linking reaction between the chemical bond active points between the raw materials, forming a more dense and uniform cross-linking network inside the EPDM rubber, minimizing the generation of by-products and the residue of harmful substances, and achieving the product EPDM rubber that is odorless and transparent, and at the same time has excellent mechanical properties as well as high temperature resistance and chemical stability.

[0024] 2. In the present application, hydroxy silicone oil and hydrogen-containing silicone oil are preferably added, both of which have a lower VOC content. The active hydrogen in the hydroxy silicone oil and the silicon-hydrogen bond (Si-H) in the hydrogen-containing silicone oil can serve as active points for the vulcanization reaction, reacting with the platinum vulcanizer to generate active centers, thereby improving the crosslinking efficiency, further promoting the stability of the crosslinking network between the EPDM molecular chains, and further improving the mechanical properties of the EPDM rubber.

[0025] 3. The EPDM rubber prepared by platinum vulcanization in this application is non-toxic and odorless, meets GB 4806.1-2016 "General Safety Requirements for Food Contact Materials and Articles", can meet the safety requirements for food contact materials in the food industry, will not cause pollution to food, and greatly expands the application field of EPDM rubber. DETAILED DESCRIPTION

[0026] The following examples further illustrate the present application in detail.

[0027] raw material Unless otherwise specified, the raw materials used in the examples and comparative examples of the present application are all commercially available products, specifically: EPDM particles, metallocene-catalyzed VNB-EPT type EPDM, selected from Mitsui Chemicals, PX-008M and PX-009M, with a VNB content of 1.5%; White carbon black is fumed white carbon black with a specific surface area of ​​(120-310) ± 20m 2 / g; Hydroxyl silicone oil, viscosity 27mm 2 / S, hydroxyl content is 8%; Liquid EPDM, selected from Mitsui Chemicals, LX-400; Hydrogenated silicone oil, with a hydrogen content of 0.07-1.6%; Platinum curing agent A, selected from Dingxing Silicone Technology Co., Ltd., DX-BJ-A; Platinum vulcanizing agent B, selected from Dingxing Silicone Technology Co., Ltd., DX-BJ-B. Example

[0028] Example 1 An odorless, transparent platinum-vulcanized EPDM rubber, the raw materials and their amounts are shown in Table 1, wherein the EPDM particles are Mitsui metallocene catalyzed VNB-EPT type PX-008M; white carbon black, with a specific surface area of ​​200±20m 2 / g; hydrogen-containing silicone oil, including 0.5 parts of hydrogen-containing silicone oil with a hydrogen content of 1.6% and 8 parts of hydrogen-containing silicone oil with a hydrogen content of 0.75%; platinum vulcanizing agent, including 0.4 parts of platinum vulcanizing agent A and 0.8 parts of platinum vulcanizing agent B.

[0029] Table 1 Components / parts by weight Example 1 Example 2 Example 3 Example 4 Example 5 EPDM Granules 115 108.8 100 115 110 White Carbon Black 30 20 60 50 40 Hydroxy silicone oil 10 5 2 2 7 Liquid EPDM 10 5 20 0 12 Hydrogen silicone oil 8.5 15 1 1 10 Platinum vulcanizing agent 1.2 2.3 2 2.5 1.8 The preparation method of the above-mentioned odorless transparent platinum vulcanized EPDM rubber comprises the following steps: S1: Put the EPDM particles into an open mill for refining, roll them, add white carbon black, hydroxy silicone oil, liquid EPDM and hydrogen-containing silicone oil, disperse them evenly and then produce sheets to obtain initial EPDM film; S2: placing the initial EPDM film in an oven, baking it at 120° C. for 30 min, and naturally cooling it to obtain a pretreated EPDM film; S3: putting the pretreated EPDM film back into the open mill for refining, first adding platinum vulcanization agent B to the pretreated EPDM film, and then adding platinum vulcanization agent A after mixing evenly, and then discharging the film after mixing evenly to obtain a prefabricated EPDM film; S4: Heat the flat vulcanizer to 170°C, place a mold with a cavity of 150×150×2mm on the flat vulcanizer to fully heat the mold, place the prefabricated EPDM film in the mold cavity, and vulcanize for 15 minutes.

[0030] Example 2 An odorless, transparent platinum-cured EPDM rubber, the raw materials and their amounts are shown in Table 1, wherein the EPDM particles are Mitsui metallocene-catalyzed VNB-EPT type, including 58.8 parts of PX-008M and 50 parts of PX-009M; white carbon black, with a specific surface area of ​​260±20m 2 / g; hydrogen-containing silicone oil, which is hydrogen-containing silicone oil with a hydrogen content of 0.07%; platinum vulcanizing agent, including 0.8 parts of platinum vulcanizing agent A and 1.5 parts of platinum vulcanizing agent B.

[0031] The preparation method of the above-mentioned odorless transparent platinum vulcanized EPDM rubber comprises the following steps: S1: Put the EPDM particles into an open mill for refining, roll them, add white carbon black, hydroxy silicone oil, liquid EPDM and hydrogen-containing silicone oil, disperse them evenly and then produce sheets to obtain initial EPDM film; S2: placing the initial EPDM film in an oven, baking it at 130° C. for 20 min, and naturally cooling it to obtain a pretreated EPDM film; S3: putting the pretreated EPDM film back into the open mill for refining, first adding platinum vulcanization agent B to the pretreated EPDM film, and then adding platinum vulcanization agent A after mixing evenly, and then discharging the film after mixing evenly to obtain a prefabricated EPDM film; S4: Heat the flat vulcanizer to 170°C, place a mold with a cavity of 150×150×2mm on the flat vulcanizer to fully heat the mold, place the prefabricated EPDM film in the mold cavity, and vulcanize for 20 minutes.

[0032] Example 3 An odorless, transparent platinum-vulcanized EPDM rubber, the raw materials and their amounts are shown in Table 1, wherein the EPDM particles are Mitsui metallocene catalyzed VNB-EPT type PX-009M; white carbon black, with a specific surface area of ​​310±20m 2 / g; hydrogen-containing silicone oil, which is hydrogen-containing silicone oil with a hydrogen content of 1.6%; platinum vulcanizing agent, including 0.8 parts of platinum vulcanizing agent A and 1.2 parts of platinum vulcanizing agent B.

[0033] The preparation method of the above-mentioned odorless transparent platinum vulcanized EPDM rubber comprises the following steps: S1: Put the EPDM particles into an open mill for refining, roll them, add white carbon black, hydroxy silicone oil, liquid EPDM and hydrogen-containing silicone oil, disperse them evenly and then produce sheets to obtain initial EPDM film; S2: placing the initial EPDM film in an oven, baking it at 120° C. for 40 min, and naturally cooling it to obtain a pretreated EPDM film; S3: putting the pretreated EPDM film back into the open mill for refining, first adding platinum vulcanization agent B to the pretreated EPDM film, and then adding platinum vulcanization agent A after mixing evenly, and then discharging the film after mixing evenly to obtain a prefabricated EPDM film; S4: Heat the flat vulcanizer to 175°C, place a mold with a cavity of 150×150×2mm on the flat vulcanizer to fully heat the mold, place the prefabricated EPDM film in the mold cavity, and vulcanize for 20 minutes.

[0034] Example 4 An odorless, transparent platinum-vulcanized EPDM rubber, the raw materials and their amounts are shown in Table 1, wherein the EPDM particles are Mitsui metallocene catalyzed VNB-EPT type PX-008M; white carbon black, with a specific surface area of ​​120±20m 2 / g; hydrogen-containing silicone oil, which is hydrogen-containing silicone oil with a hydrogen content of 1.6%; platinum vulcanizing agent, including 1 part of platinum vulcanizing agent A and 1.5 parts of platinum vulcanizing agent B.

[0035] The preparation method of the above-mentioned odorless transparent platinum vulcanized EPDM rubber comprises the following steps: S1: Put the EPDM particles into an open mill for refining, roll them, add white carbon black, hydroxy silicone oil and hydrogen silicone oil, disperse them evenly and then produce sheets to obtain an initial EPDM film; S2: placing the initial EPDM film in an oven, baking it at 130° C. for 30 min, and naturally cooling it to obtain a pretreated EPDM film; S3: putting the pretreated EPDM film back into the open mill for refining, first adding platinum vulcanization agent B to the pretreated EPDM film, and then adding platinum vulcanization agent A after mixing evenly, and then discharging the film after mixing evenly to obtain a prefabricated EPDM film; S4: Heat the flat vulcanizer to 175°C, place a mold with a cavity of 150×150×2mm on the flat vulcanizer to fully heat the mold, place the prefabricated EPDM film in the mold cavity, and vulcanize for 15 minutes.

[0036] Example 5 An odorless, transparent platinum-cured EPDM rubber, the raw materials and their amounts are shown in Table 1, wherein the EPDM particles are Mitsui metallocene-catalyzed VNB-EPT type, including 50 parts of PX-008M and 60 parts of PX-009M; white carbon black, with a specific surface area of ​​200±20m 2 / g; hydrogen-containing silicone oil, which is hydrogen-containing silicone oil with a hydrogen content of 1.6%; platinum vulcanizing agent, including 0.8 parts of platinum vulcanizing agent A and 1 part of platinum vulcanizing agent B.

[0037] The preparation method of the above-mentioned odorless transparent platinum vulcanized EPDM rubber comprises the following steps: S1: Put the EPDM particles into an open mill for refining, roll them, add white carbon black, hydroxy silicone oil, liquid EPDM and hydrogen-containing silicone oil, disperse them evenly and then produce sheets to obtain initial EPDM film; S2: placing the initial EPDM film in an oven, baking it at 120° C. for 35 min, and naturally cooling it to obtain a pretreated EPDM film; S3: putting the pretreated EPDM film back into the open mill for refining, first adding platinum vulcanization agent B to the pretreated EPDM film, and then adding platinum vulcanization agent A after mixing evenly, and then discharging the film after mixing evenly to obtain a prefabricated EPDM film; S4: Heat the flat vulcanizer to 180°C, place a mold with a cavity of 150×150×2mm on the flat vulcanizer to fully heat the mold, place the prefabricated EPDM film in the mold cavity, and vulcanize for 15 minutes.

[0038] Example 6 An odorless and transparent platinum-vulcanized EPDM rubber is different from Example 1 in that the platinum vulcanizing agent is platinum vulcanizing agent A, and step S3 is specifically as follows: The pretreated EPDM film is put back into the open mill for refining, platinum curing agent A is first added to the pretreated EPDM film, and the film is produced after being mixed evenly to obtain a prefabricated EPDM film; The other steps are the same as those in Example 1.

[0039] Example 7 An odorless and transparent platinum-vulcanized EPDM rubber is different from Example 1 in that the platinum vulcanizing agent is platinum vulcanizing agent B, and step S3 is specifically as follows: The pretreated EPDM film is put back into the open mill for refining, platinum vulcanizing agent B is first added to the pretreated EPDM film, and the film is produced after being mixed evenly to obtain a prefabricated EPDM film; The other steps are the same as those in Example 1.

[0040] Comparative Example Comparative Example 1 An odorless and transparent platinum-vulcanized EPDM rubber is different from Example 1 in that hydroxy silicone oil is not added to the raw materials, and other steps are the same as those of Example 1.

[0041] Comparative Example 2 An odorless and transparent platinum-vulcanized EPDM rubber is different from Example 1 in that no hydrogen-containing silicone oil is added to the raw materials, and other steps are the same as those of Example 1.

[0042] Performance testing Test Example 1 Mechanical Properties Test The following relevant performance test tests were performed on the odorless transparent platinum vulcanized EPDM rubber obtained in Examples 1-7 and Comparative Examples 1-2. Each test was performed 3 times, and the average value of the 3 tests was taken as the final result and recorded in Table 2.

[0043] 1. Hardness: Refer to GB / T 531.1-2008 "Test method for indentation hardness of vulcanized rubber or thermoplastic rubber" to test the Shore hardness; 2. Tensile strength: Refer to GB / T 528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber", test the tensile strength and calculate the elongation at break; 3. Tear strength: Refer to GB / T 529-2008 "Determination of tear strength of vulcanized rubber or thermoplastic rubber" to test the tear strength; Table 2 Test Example 2 Sensory test of odor and appearance Odor is evaluated with reference to the provisions of PV3900. The evaluation method is as follows: 1. Select 5 healthy assessors who have no olfactory or visual preferences to conduct odor identification; 2. Prepare an odorless glass bottle specially specified by the odor detection standard PV 3900 as a container bottle. Under a standard laboratory environment, put the odorless transparent platinum vulcanized EPDM rubber samples obtained in Examples 1-7 and Comparative Examples 1-2 into the container bottles, respectively, put them in an oven at 80±5°C for 2 hours, and cool them to about 60°C; 3. Five appraisers conducted odor evaluation on each group of samples and observed the appearance color of the samples. The average of the odor evaluation results given by the five appraisers was taken as the final result and recorded in Table 3.

[0044] The odor evaluation criteria are: Level 1: Odorless; Level 2: There is an odor, but no disturbing odor; Level 3: There is a noticeable odor, but no disturbing odor; Level 4: There is a disturbing odor; Level 5: There is a strong disturbing odor.

[0045] Table 3 Test Example 3 Food Contact Material Safety Test With reference to the method provisions of GB 4806.1-2016 "National Food Safety Standard General Safety Requirements for Food Contact Materials and Products", the odorless transparent platinum-vulcanized EPDM rubber obtained in Examples 1-7 was tested for physical and chemical indicators (such as evaporation residue, potassium permanganate consumption, heavy metals, etc.), and the relevant performance test results are recorded in Table 4.

[0046] Table 4 According to the performance test results of test examples 1-3, it can be seen that the present application abandons the traditional sulfur vulcanization and peroxide vulcanization methods, and the EPDM rubber prepared by the platinum vulcanization method has the characteristics of being odorless and transparent, with excellent mechanical properties, and the food hygiene grade performance meets the national standards. It has excellent safety and environmental protection performance and can be used in the food industry to prepare food contact materials, especially conveying hoses and pipes, food conveyor belts, food storage containers, food packaging materials, and food rubber gloves in the food processing process. The odorless and transparent platinum vulcanized EPDM rubber of the present application can meet the requirements of GB 4806.1-2016 "General Safety Requirements for Food Contact Materials and Products" for food contact materials.

[0047] According to the data results in Table 2, it can be seen that the tensile strength of the platinum-vulcanized EPDM rubber of the present application can reach 5.9-7.8 MPa, the elongation at break can reach 217-380%, and the tear strength can reach 18.7-23.4 kN / m, which can meet the performance requirements when used in specific scenarios in the food industry and other fields, and has excellent flexibility and mechanical properties.

[0048] It can be seen from the performance test results of Examples 1-5 and Examples 6-7 that by precisely controlling the dosage and addition time of platinum vulcanizing agent A and agent B, the start and progress of the vulcanization reaction can be more accurately controlled, thereby achieving precise control of the vulcanization process, promoting the complete progress of the vulcanization reaction, and reducing the generation of harmful substances.

[0049] It can be seen from the performance test results of Examples 1-7 and Comparative Examples 1-2 that the addition of hydroxy silicone oil and hydrogen-containing silicone oil can improve the crosslinking efficiency in the vulcanization reaction, further promote the stability of the crosslinking network between EPDM molecular chains, and improve the mechanical properties of EPDM rubber. Furthermore, this helps to prevent other side reactions that may produce odors, and further ensure that the product EPDM rubber is non-toxic and odorless.

[0050] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. An odorless, transparent platinum-vulcanized EPDM rubber, characterized in that: In parts by weight, the raw materials include 100-115 parts of EPDM particles, 20-60 parts of white carbon black, 2-10 parts of hydroxy silicone oil, 0-20 parts of liquid EPDM, 1-15 parts of hydrogen-containing silicone oil and 1.2-2.5 parts of platinum vulcanizing agent.

2. The odorless, transparent platinum-vulcanized EPDM rubber according to claim 1, characterized in that: In parts by weight, the platinum vulcanizing agent includes 0.4-1 parts of platinum vulcanizing agent A and 0.8-1.5 parts of platinum vulcanizing agent B.

3. The odorless, transparent platinum-vulcanized EPDM rubber according to claim 1, characterized in that: In parts by weight, the EPDM particles are any one or a combination of two of PX-008M and PX-009M of Mitsui metallocene catalyst VNB-EPT type.

4. The odorless, transparent platinum-vulcanized EPDM rubber according to claim 1, characterized in that: The hydrogen content of the hydrogen-containing silicone oil is 0.07-1.6%.

5. The odorless, transparent platinum-vulcanized EPDM rubber according to claim 1, characterized in that: The white carbon black is fumed white carbon black, and the specific surface area is (120-310) ± 20m 2 / g.

6. The odorless, transparent platinum-vulcanized EPDM rubber according to claim 1, characterized in that: The viscosity of the hydroxy silicone oil is 27 mm 2 ∕S, hydroxyl content is 8%.

7. A method for preparing an odorless and transparent platinum-vulcanized EPDM rubber according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1: EPDM particles are subjected to open milling, rolled, and then white carbon black, hydroxy silicone oil, liquid EPDM and hydrogen-containing silicone oil are added, and the particles are uniformly dispersed and then produced into sheets to obtain an initial EPDM film; S2: baking the initial EPDM film at 120-130° C. for 20-40 min, and naturally cooling it to obtain a pretreated EPDM film; S3: first add platinum vulcanization agent B to the pretreated EPDM film, mix evenly, then add platinum vulcanization agent A, mix evenly, and then produce a sheet to obtain a prefabricated EPDM film; S4: Place the prefabricated EPDM film in the mold at 170-180°C and vulcanize for 15-20 minutes.

8. Use of the odorless, transparent platinum-vulcanized EPDM rubber according to any one of claims 1 to 6 in the preparation of food contact materials.

9. The use according to claim 8, wherein the food contact materials include conveying hoses and pipes in food processing, food conveyor belts, food storage containers, food packaging materials and food rubber gloves.

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