A brominated butyl rubber stopper and its preparation method and treatment method

Abstract

The invention discloses a brominated butyl rubber plug and a preparation method and a treatment method thereof, belonging to the technical field of rubber plugs. The brominated butyl rubber plug comprises 100 parts of Exxpro TM The present invention also provides a method for preparing the above-mentioned brominated butyl rubber plug, comprising: Exxpro TM After the special elastomer is added to the internal mixer for the first mixing, the material is discharged at 140-145°C; the mixed rubber is put into the extruder, and the temperature of the extruder is 90-100°C; the obtained rubber sheet is placed in a vulcanizer for vulcanization; the product is punched into a single bromobutyl rubber plug by a punching machine. The rubber plug proposed by the present invention improves the stability of the rubber plug and has good drug compatibility.

Description

Technical Field

[0001] The invention relates to the technical field of rubber stoppers, and in particular to a brominated butyl rubber stopper and a preparation method and a treatment method thereof. Background Art

[0002] Bromobutyl rubber stopper, as a type of halogenated butyl rubber stopper, is an important sealing material in pharmaceutical packaging materials. Since it is in direct contact with the drug, cross-reactions may occur between the rubber stopper and the drug through contact, absorption, adsorption or leaching, thereby contaminating or affecting the drug. Therefore, high drug compatibility requirements are placed on it.

[0003] In addition, when a needle is inserted into the halogenated butyl rubber stopper, there is a problem of needle puncture debris. If the debris of the bromobutyl rubber stopper enters the drug, it will contaminate the drug to a certain extent. Therefore, the number and possibility of needle puncture debris should be reduced. How to meet the requirements of drug compatibility and needle puncture debris is a problem that the existing technology needs to solve. Summary of the invention

[0004] The purpose of the present invention is to overcome the above technical deficiencies, provide a brominated butyl rubber stopper and a preparation method and a treatment method thereof, and solve the technical problem of how to improve the drug compatibility of brominated butyl rubber stoppers in the prior art.

[0005] In order to achieve the above technical purpose, the technical solution of the present invention provides a brominated butyl rubber stopper, which comprises 100 parts of Exxpro TM Special elastomer, 40-50 parts of calcined kaolin, 5-10 parts of first talc, 2-5 parts of second talc, 2-4 parts of PE wax, 2-6 parts of polytetrafluoroethylene nanoparticles, 1-3 parts of aromatic siloxane, 1-3 parts of titanium dioxide, 2-4 parts of carbon black and 1-2 parts of sulfur.

[0006] Furthermore, in certain embodiments, 2-4 parts of magnesium oxide are included.

[0007] In addition, the present invention also provides a method for preparing the above-mentioned brominated butyl rubber stopper, comprising the following steps:

[0008] S1. Exxpro TM After the special elastomer is added to the internal mixer for the first mixing, the calcined kaolin is added for the second mixing, and then the first talc powder, carbon black, PE wax, titanium dioxide and aromatic siloxane are added for the third mixing, and after mixing, the material is discharged at 140-145° C.;

[0009] S2, putting the rubber material discharged from step S1 into an open mill, drawing a knife to cool the rubber on the open mill, drawing out the rubber, adding polytetrafluoroethylene nanoparticles, sulfur and second talc powder to carry out the fourth mixing, pounding and refining the rubber for 7-10 minutes, the temperature during the refining process is 90-95° C., and cooling the lower sheet for 1-2 minutes to obtain a mixed rubber;

[0010] S3, putting the rubber compound obtained in step S2 into an extruder, and the extruded rubber material is calendered by a calender, then cooled and cut into pieces; the temperature of the extruder is 90-100°C;

[0011] S4, the film obtained in step S3 is placed in a vulcanizing machine for vulcanization;

[0012] S5. The vulcanized product is punched into individual bromobutyl rubber plugs by a punching machine.

[0013] Furthermore, after step S5, the method further includes:

[0014] S6. Clean the brominated butyl rubber stopper with a cleaning agent, then clean it with water, then siliconize it, and then dry it to obtain the cleaned brominated butyl rubber stopper.

[0015] Furthermore, in step S1, the first mixing time is 2-3 minutes, and the second mixing time is 4-5 minutes.

[0016] Furthermore, in step S1, the third mixing time is 3-4 minutes.

[0017] Furthermore, in step S2, the fourth mixing time is 5-6 minutes.

[0018] Further, in step S4, the vulcanization process parameters are: vulcanization process parameters: vulcanization temperature 190-195° C., vulcanization pressure 20-22 MPa, and vulcanization time 300-350 s.

[0019] Furthermore, in step S2, polytetrafluoroethylene nanoparticles, magnesium oxide, sulfur and second talc are added into the rubber to carry out the fourth mixing.

[0020] Further, in step S6, the siliconization includes: mixing silicone oil and water in a volume ratio of 1:(4-5) to obtain a mixed liquid, and then mixing the brominated butyl rubber stopper with the mixed liquid for 15-20 minutes to complete the siliconization.

[0021] In addition, the present invention also proposes a method for processing the above-mentioned brominated butyl rubber stopper, comprising: applying a coating liquid on the surface of the brominated butyl rubber stopper and curing it at 120-140°C; the coating liquid, calculated by weight, comprises 40-60 parts of polytetrafluoroethylene, 5-10 parts of epoxy resin, and 100-120 parts of ethyl acetate.

[0022] Compared with the prior art, the beneficial effects of the present invention include: the brominated butyl rubber plug proposed by the present invention, under the coordination of various components, especially Exxpro TM Special elastomers and polytetrafluoroethylene nanoparticles can improve the cross-linking effect of the components of the rubber stopper under the action of aromatic siloxane. The polytetrafluoroethylene nanoparticles play an anchoring role. Under the action of aromatic siloxane, they connect and fix other components like a "net", thereby improving the stability of the rubber stopper and thus having better drug compatibility. In addition, polytetrafluoroethylene nanoparticles have an internal lubricating effect in the rubber stopper, thereby reducing the amount of debris caused by needle puncture. DETAILED DESCRIPTION

[0023] This specific embodiment provides a brominated butyl rubber stopper, which includes 100 parts of Exxpro TM Special elastomer, 40-50 parts of calcined kaolin, 5-10 parts of first talc powder, 2-5 parts of second talc powder, 2-4 parts of PE wax, 2-6 parts of polytetrafluoroethylene nanoparticles, 1-3 parts of aromatic siloxane, 1-3 parts of titanium dioxide, 2-4 parts of carbon black, and 1-2 parts of sulfur.

[0024] In certain embodiments, the brominated butyl rubber stopper further comprises 2-4 parts of magnesium oxide. The addition of magnesium oxide can fill the pores of the rubber stopper and further improve the drug compatibility of the rubber stopper.

[0025] This specific embodiment also proposes a method for preparing the above-mentioned brominated butyl rubber stopper, comprising the following steps:

[0026] S1. Exxpro TM After the special elastomer is added to the internal mixer for the first mixing for 2-3 minutes, the calcined kaolin is added for the second mixing for 4-5 minutes, and then the first talc powder, carbon black, PE wax, titanium dioxide and aromatic siloxane are added for the third mixing for 3-4 minutes. After mixing, the material is discharged at 140-145°C;

[0027] S2, putting the rubber material discharged from step S1 into an open mill, drawing the rubber material on the open mill for 2-3 times, adding polytetrafluoroethylene nanoparticles, sulfur and the second talcum powder to the rubber material for the fourth mixing for 5-6 minutes, pounding the rubber material for 7-10 minutes, the temperature during the mixing process is 90-95° C., and the lower sheet is cooled for 1-2 minutes to obtain a mixed rubber; in some embodiments, the rubber material is drawn and added with polytetrafluoroethylene nanoparticles, oxidase, sulfur and the second talcum powder for the fourth mixing;

[0028] S3, putting the rubber compound obtained in step S2 into an extruder, and the extruded rubber material is calendered by a calender, then cooled and cut into pieces; the temperature of the extruder is 90-100°C;

[0029] S4. The film obtained in step S3 is placed in a vulcanizer for vulcanization. The vulcanization process parameters are: vulcanization temperature 190-195°C, vulcanization pressure 20-22Mpa, and vulcanization time 300-350s;

[0030] S5, punching the vulcanized product into individual bromobutyl rubber plugs through a punching machine;

[0031] S6. Clean the brominated butyl rubber plug with a cleaning agent, then clean it with water, then siliconize it, and then dry it to obtain the cleaned brominated butyl rubber plug; the siliconization includes: mixing silicone oil and water in a volume ratio of 1:(4-5) to obtain a mixed liquid, and then mixing the brominated butyl rubber plug with the mixed liquid for 15-20 minutes to complete the siliconization.

[0032] The polytetrafluoroethylene nanoparticles, magnesium oxide, sulfur and the second talc powder are added later to facilitate uniform dispersion in the rubber compound and promote vulcanization efficiency. In addition, they can fill the pores in the rubber compound, reduce the pores of the rubber stopper formed subsequently, and improve the drug compatibility of the rubber stopper.

[0033] This specific embodiment also proposes a method for processing the above-mentioned brominated butyl rubber stopper, comprising: applying a coating liquid on the surface of the brominated butyl rubber stopper and curing it at 120-140°C; the coating liquid, calculated by weight, comprises 40-60 parts of polytetrafluoroethylene, 5-10 parts of epoxy resin, and 100-120 parts of ethyl acetate.

[0034] Continuing to apply the coating liquid on the rubber stopper can further isolate the drug and the rubber stopper, further improve the drug compatibility of the rubber stopper, and the curing time is short, which may be related to the fact that the rubber stopper itself contains polytetrafluoroethylene.

[0035] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0036] Example 1

[0037] This embodiment provides a brominated butyl rubber stopper, which includes 100 parts of Exxpro TM Special elastomer, 50 parts of calcined kaolin, 5 parts of first talc, 2 parts of second talc, 3 parts of PE wax, 5 parts of polytetrafluoroethylene nanoparticles, 1 part of aromatic siloxane, 3 parts of titanium dioxide, 2 parts of carbon black and 2 parts of sulfur.

[0038] This embodiment also provides a method for preparing the above-mentioned brominated butyl rubber stopper, comprising the following steps:

[0039] S1. Exxpro TM After the special elastomer is added to the internal mixer for the first mixing for 3 minutes, the calcined kaolin is added for the second mixing for 4 minutes, and then the first talc powder, carbon black, PE wax, titanium dioxide and aromatic siloxane are added for the third mixing for 3 minutes. After mixing, the material is discharged at 140°C;

[0040] S2, putting the rubber material discharged from step S1 into an open mill, drawing the rubber material on the open mill for 2 times, adding polytetrafluoroethylene nanoparticles, sulfur and second talc powder to the rubber material for the fourth mixing for 6 minutes, pounding the rubber material for 10 minutes, the temperature during the mixing process is 90° C., and cooling the lower sheet for 1 minute to obtain a mixed rubber;

[0041] S3, putting the rubber compound obtained in step S2 into an extruder, and cooling and cutting the extruded rubber compound after calendering by a calender; the temperature of the extruder is 90°C;

[0042] S4, the film obtained in step S3 is placed in a vulcanizer for vulcanization; the vulcanization process parameters are: vulcanization temperature 195°C, vulcanization pressure 20Mpa, vulcanization time 300s;

[0043] S5, punching the vulcanized product into individual bromobutyl rubber plugs through a punching machine;

[0044] S6. Clean the brominated butyl rubber plug with a cleaning agent, then clean it with water, then siliconize it, and then dry it to obtain the cleaned brominated butyl rubber plug; the siliconization includes: mixing silicone oil and water in a volume ratio of 1:4 to obtain a mixed liquid, and then mixing the brominated butyl rubber plug with the mixed liquid for 15 minutes to complete the siliconization.

[0045] Example 2

[0046] This embodiment provides a brominated butyl rubber stopper, which includes 100 parts of Exxpro TM Special elastomer, 45 parts of calcined kaolin, 8 parts of first talc, 3 parts of second talc, 2 parts of PE wax, 2 parts of polytetrafluoroethylene nanoparticles, 2 parts of aromatic siloxane, 2 parts of titanium dioxide, 3 parts of carbon black and 1 part of sulfur.

[0047] This embodiment also provides a method for preparing the above-mentioned brominated butyl rubber stopper, comprising the following steps:

[0048] S1. Exxpro TM After the special elastomer is added to the internal mixer for the first mixing for 2 minutes, the calcined kaolin is added for the second mixing for 5 minutes, and then the first talc, carbon black, PE wax, titanium dioxide and aromatic siloxane are added for the third mixing for 4 minutes. After mixing, the material is discharged at 145°C;

[0049] S2, putting the rubber material discharged from step S1 into an open mill, drawing the rubber material on the open mill for 3 times, adding polytetrafluoroethylene nanoparticles, sulfur and second talc powder to the rubber material for the fourth mixing for 5 minutes, pounding the rubber material for 8 minutes, the temperature during the mixing process is 95° C., and cooling the lower sheet for 2 minutes to obtain a mixed rubber;

[0050] S3, putting the rubber compound obtained in step S2 into an extruder, and the extruded rubber compound is calendered by a calender, cooled, and cut into pieces; the temperature of the extruder is 100°C;

[0051] S4, the film obtained in step S3 is placed in a vulcanizer for vulcanization; the vulcanization process parameters are: vulcanization temperature 190°C, vulcanization pressure 21Mpa, vulcanization time 330s;

[0052] S5, punching the vulcanized product into individual bromobutyl rubber plugs through a punching machine;

[0053] S6. Clean the brominated butyl rubber plug with a cleaning agent, then clean it with water, then siliconize it, and then dry it to obtain the cleaned brominated butyl rubber plug; the siliconization includes: mixing silicone oil and water in a volume ratio of 1:5 to obtain a mixed liquid, and then mixing the brominated butyl rubber plug with the mixed liquid for 18 minutes to complete the siliconization.

[0054] Example 3

[0055] This embodiment provides a brominated butyl rubber stopper, which includes 100 parts of Exxpro TM Special elastomer, 40 parts of calcined kaolin, 10 parts of first talc, 5 parts of second talc, 4 parts of PE wax, 6 parts of polytetrafluoroethylene nanoparticles, 3 parts of aromatic siloxane, 1 part of titanium dioxide, 4 parts of carbon black and 1 part of sulfur.

[0056] This embodiment also provides a method for preparing the above-mentioned brominated butyl rubber stopper, comprising the following steps:

[0057] S1. Exxpro TM The special elastomer is added to the internal mixer for the first mixing for 2 minutes, and then the calcined kaolin is added for the second mixing for 5 minutes, and then the first talc powder, carbon black, PE wax, titanium dioxide and aromatic siloxane are added for the third mixing for 4 minutes, and after mixing, the material is discharged at 100°C;

[0058] S2, putting the rubber material discharged from step S1 into an open mill, drawing the rubber material on the open mill for 3 times, adding polytetrafluoroethylene nanoparticles, sulfur and second talc powder to the rubber material for the fourth mixing for 5 minutes, pounding the rubber material for 7 minutes, the temperature during the mixing process is 90° C., and cooling the lower sheet for 1 minute to obtain a mixed rubber;

[0059] S3, putting the rubber compound obtained in step S2 into an extruder, and cooling and cutting the extruded rubber compound after calendering by a calender; the temperature of the extruder is 95°C;

[0060] S4, the film obtained in step S3 is placed in a vulcanizer for vulcanization; the vulcanization process parameters are: vulcanization temperature 190°C, vulcanization pressure 22Mpa, vulcanization time 350s;

[0061] S5, punching the vulcanized product into individual bromobutyl rubber plugs through a punching machine;

[0062] S6. Clean the brominated butyl rubber plug with a cleaning agent, then clean it with water, then siliconize it, and then dry it to obtain the cleaned brominated butyl rubber plug; the siliconization includes: mixing silicone oil and water in a volume ratio of 1:5 to obtain a mixed liquid, and then mixing the brominated butyl rubber plug with the mixed liquid for 20 minutes to complete the siliconization.

[0063] Example 4

[0064] The difference between the brominated butyl rubber stopper in this embodiment and that in embodiment 1 is that 3 parts of magnesium oxide are further included.

[0065] The preparation method of the brominated butyl rubber stopper proposed in this embodiment is the same as that in Embodiment 1, with the only difference being step S2: S2, putting the rubber material discharged from step S1 into an open mixing mill, cooling the rubber material by pulling a knife on the open mixing mill twice, adding polytetrafluoroethylene nanoparticles, sulfur, magnesium oxide and a second talcum powder to the rubber material for a fourth mixing for 6 minutes, pounding and mixing the rubber material for 10 minutes, the temperature during the mixing process is 90°C, and cooling the lower sheet for 1 minute to obtain a mixed rubber material.

[0066] Example 5

[0067] The difference between the brominated butyl rubber stopper of this embodiment and that of embodiment 2 is that 2 parts of magnesium oxide are also included.

[0068] The preparation method of the brominated butyl rubber stopper proposed in this embodiment is the same as that in Embodiment 1, with the only difference being step S2: S2, putting the rubber material discharged from step S1 into an open mixing mill, cooling the rubber material by pulling a knife on the open mixing mill for 3 times, adding polytetrafluoroethylene nanoparticles, sulfur, magnesium oxide and a second talcum powder to the rubber material for a fourth mixing for 5 minutes, pounding and mixing the rubber material for 8 minutes, the temperature during the mixing process is 95°C, and cooling the lower sheet for 2 minutes to obtain a mixed rubber material.

[0069] Example 6

[0070] The difference between the brominated butyl rubber stopper of this embodiment and that of embodiment 3 is that 4 parts of magnesium oxide are further included.

[0071] The preparation method of the brominated butyl rubber stopper proposed in this embodiment is the same as that in Embodiment 1, with the only difference being step S2: S2, putting the rubber material discharged from step S1 into an open mixing mill, cooling the rubber material by pulling a knife on the open mixing mill for 3 times, adding polytetrafluoroethylene nanoparticles, sulfur, magnesium oxide and a second talcum powder to the rubber material for a fourth mixing for 5 minutes, pounding and mixing the rubber material for 7 minutes, the temperature during the mixing process is 90°C, and cooling the lower sheet for 1 minute to obtain a mixed rubber material.

[0072] Example 7

[0073] This embodiment proposes a method for treating the above-mentioned brominated butyl rubber stopper, comprising: applying a coating liquid on the surface of the brominated butyl rubber stopper obtained in Example 4 and curing it at 130°C for 5 hours; the coating liquid, calculated by weight, comprises 50 parts of polytetrafluoroethylene, 5 parts of epoxy resin, and 110 parts of ethyl acetate.

[0074] Example 8

[0075] This embodiment proposes a method for treating the above-mentioned brominated butyl rubber stopper, comprising: applying a coating liquid on the surface of the brominated butyl rubber stopper obtained in Example 4 and curing it at 120°C for 6 hours; the coating liquid, calculated by weight, comprises 60 parts of polytetrafluoroethylene, 10 parts of epoxy resin, and 120 parts of ethyl acetate.

[0076] Example 9

[0077] This embodiment proposes a method for treating the above-mentioned brominated butyl rubber stopper, comprising: applying a coating liquid on the surface of the brominated butyl rubber stopper obtained in Example 4 and curing it at 140°C for 5 hours; the coating liquid, calculated by weight, comprises 55 parts of polytetrafluoroethylene, 5 parts of epoxy resin, and 100 parts of ethyl acetate.

[0078] Comparative Example 1

[0079] The brominated butyl rubber stopper proposed in this comparative example is different from that in Example 1 in that it does not contain polytetrafluoroethylene nanoparticles and 7 parts of the second talc powder, and the other components and amounts are the same as those in Example 1.

[0080] The preparation method of the brominated butyl rubber stopper proposed in this comparative example is the same as that in Example 1.

[0081] Performance Testing:

[0082] Container tightness test

[0083] Experimental method: Method under [Sealing performance of rubber stoppers and containers] of YBB00052005-2015 "Halogenated butyl rubber stoppers for sterile powder for injection". Take 8 bromobutyl rubber stoppers of Examples 1-9 and Comparative Example 1 respectively. The experimental results show that the sealing performance of bromobutyl rubber stoppers of Examples 1-9 and Comparative Example 1 with containers is very good.

[0084] Drug compatibility testing

[0085] The experimental drugs selected highly sensitive active drugs: 1. Cefotiam for injection, specification 1.0g, 2. Ceftriaxone sodium for injection, specification 1.0g. The above drugs were put into bottles covered with rubber stoppers of Examples 1-9 and Comparative Example 1 and inverted, and the clarity was observed at different time periods. The results are shown in Table 1-2.

[0086] Table 1 Drug compatibility test - Clarity of cefotiam for injection

[0087]

[0088]

[0089] Table 2 Drug compatibility test - clarity of ceftriaxone sodium for injection

[0090] Group 0 months 3 months 6 months 10 months Example 1 clarify clarify clarify ＞2 Example 2 clarify clarify clarify ＞2 Example 3 clarify clarify clarify ＞2 Example 4 clarify clarify clarify ＞1 Example 5 clarify clarify clarify ＞1 Example 6 clarify clarify clarify ＞1 Example 7 clarify clarify clarify clarify Example 8 clarify clarify clarify clarify Example 9 clarify clarify clarify clarify Comparative Example 1 clarify clarify ＞1 ＞3

[0091] It can be seen from Tables 1 and 2 that the brominated butyl rubber stoppers treated in Examples 7-9 proposed by the present invention have better drug compatibility.

[0092] Puncture chip test

[0093] The brominated butyl rubber stoppers of Examples 1-9 and Comparative Example 1 were pierced with an injection needle. Each brominated butyl rubber stopper was pierced 100 times by the injection needle, and the debris situation was recorded. The results are shown in Table 3.

[0094] Table 3 Debris shedding of bromobutyl rubber stopper

[0095] Group Puncture debris, grains / 100 needles Example 1 1 Example 2 2 Example 3 1 Example 4 0 Example 5 0 Example 6 0 Example 7 0 Example 8 0 Example 9 0 Comparative Example 1 6

[0096] It can be seen from Table 3 that the rubber stoppers prepared in Examples 4 to 6 and the rubber stoppers treated in Examples 7 to 9 had no debris falling off, while the rubber stoppers prepared in Examples 1 to 3 and the rubber stopper in Comparative Example 1 had debris falling off.

[0097] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A brominated butyl rubber stopper, characterized in that: Calculated by weight, including 100 parts of Exxpro TM Special elastomer, 40-50 parts of calcined kaolin, 5-10 parts of first talc, 2-5 parts of second talc, 2-4 parts of PE wax, 2-6 parts of polytetrafluoroethylene nanoparticles, 1-3 parts of aromatic siloxane, 1-3 parts of titanium dioxide, 2-4 parts of carbon black and 1-2 parts of sulfur; also including 2-4 parts of magnesium oxide; The brominated butyl rubber stopper is prepared by the following steps: S1. Exxpro TM After the special elastomer is added to the internal mixer for the first mixing, the calcined kaolin is added for the second mixing, and then the first talc powder, carbon black, PE wax, titanium dioxide and aromatic siloxane are added for the third mixing, and after mixing, the material is discharged at 140-145° C.; S2, putting the rubber material discharged from step S1 into an open mill, drawing a knife to cool the rubber on the open mill, drawing out the rubber, adding polytetrafluoroethylene nanoparticles, magnesium oxide, sulfur and second talc powder to carry out the fourth mixing, pounding and refining the rubber for 7-10 minutes, the temperature during the refining process is 90-95° C., and cooling the lower sheet for 1-2 minutes to obtain a mixed rubber; S3, putting the rubber compound obtained in step S2 into an extruder, and the extruded rubber material is calendered by a calender, then cooled and cut into pieces; the temperature of the extruder is 90-100°C; S4. The film obtained in step S3 is placed in a vulcanizer for vulcanization; the vulcanization process parameters are: vulcanization temperature 190-195° C., vulcanization pressure 20-22 MPa, and vulcanization time 300-350 s; S5, punching the vulcanized product into individual bromobutyl rubber plugs through a punching machine; S6, cleaning the brominated butyl rubber stopper with a cleaning agent, then cleaning with water, then siliconizing, and then drying to obtain a cleaned brominated butyl rubber stopper; the siliconizing comprises: mixing silicone oil and water in a volume ratio of 1:(4-5) to obtain a mixed liquid, then mixing the brominated butyl rubber stopper with the mixed liquid for 15-20 minutes to complete the siliconization; The coating liquid is coated on the surface of the brominated butyl rubber plug and cured at 120-140° C. The coating liquid comprises 40-60 parts of polytetrafluoroethylene, 5-10 parts of epoxy resin and 100-120 parts of ethyl acetate in parts by weight.

2. The brominated butyl rubber stopper according to claim 1, characterized in that In step S1, the first mixing time is 2-3 minutes, the second mixing time is 4-5 minutes; and / or the third mixing time is 3-4 minutes.

3. The brominated butyl rubber stopper according to claim 1, characterized in that In step S2, the fourth mixing time is 5-6 minutes.

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