A butyl rubber, its preparation method and application

Abstract

This invention discloses a butyl rubber, its preparation method, and its application. The raw materials for the butyl rubber include butyl rubber, a vulcanizing agent, and N-cyclohexylthiophthalimide. The vulcanizing agent includes sulfur and selective N,N'-tetramethyldithiocarboxylamine. The mass ratio of butyl rubber, vulcanizing agent, and N-cyclohexylthiophthalimide is 1:0.001-0.01:0.015-0.2. The preparation method of the butyl rubber includes: melting the butyl rubber under heating and stirring conditions, then adding the vulcanizing agent, maintaining the temperature and stirring, and starting the timer after the vulcanizing agent is added until the reaction time reaches 5-20 minutes, then adding N-cyclohexylthiophthalimide, maintaining the temperature and stirring. The reaction time is inversely proportional to the amount of vulcanizing agent added. The butyl rubber prepared by this method has excellent peel strength, and when used in waterproof membranes, only cohesive failure occurs during peeling.

Description

Technical Field

[0001] This invention relates to the field of waterproof materials technology, and more particularly to adhesive materials for waterproof membranes, specifically to a butyl rubber, its preparation method, and its application. Background Technology

[0002] Butyl rubber, abbreviated as IIR, is an abbreviation for Isobutylene Isoprene Rubber. It is a type of synthetic rubber synthesized from isobutylene and a small amount of isoprene. It has good chemical and thermal stability, and its most outstanding features are air tightness and water tightness. Its air permeability is only 1 / 7 that of natural rubber and 1 / 5 that of styrene-butadiene rubber, while its steam permeability is 1 / 200 that of natural rubber and 1 / 140 that of styrene-butadiene rubber. Therefore, it is mainly used to manufacture various inner tubes, steam pipes, water tires, dam bottom layers, gaskets, and other rubber products. Currently, in the field of building waterproofing, butyl rubber, touted as environmentally friendly, has been widely adopted to replace asphalt. It is mainly used in the adhesive layer of self-adhesive rolls or tapes. For example, commonly used butyl rubber pressure-sensitive adhesives can be coated on sheets such as TPO sheets (also known as thermoplastic polyolefin sheets) to obtain waterproof rolls that can bond with other substrates such as other rolls and color steel plates. A reasonable adhesive system should exhibit cohesive failure of the adhesive layer or a mixed failure of cohesive failure and interface failure when subjected to stress. Ideally, it should only exhibit cohesive failure of the adhesive layer. However, current practice has found that existing conventional butyl rubber pressure-sensitive adhesives generally have insufficient adhesion. Even if the adhesion is improved, there is still a problem of interface failure when peeling, showing a clear trade-off. Summary of the Invention

[0003] The purpose of this invention is to overcome one or more shortcomings in the prior art and provide an improved method for preparing butyl rubber. The butyl rubber prepared by this method has excellent peel strength and only cohesive failure occurs when the waterproof membrane is peeled off.

[0004] The present invention also provides a butyl rubber prepared by the method described above.

[0005] The present invention also provides an application of the butyl rubber prepared by the above-described method in waterproof membranes.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] A method for preparing butyl rubber, wherein the raw materials for the butyl rubber include butyl rubber, a vulcanizing agent, and N-cyclohexylthiophthalimide, wherein the vulcanizing agent includes sulfur and selective N,N'-tetramethyldithiocarbonylamine; the mass ratio of the butyl rubber, the vulcanizing agent, and the N-cyclohexylthiophthalimide is 1:0.001-0.01:0.015-0.2.

[0008] The preparation method of this butyl rubber includes: melting butyl rubber under heating and stirring conditions, then adding a vulcanizing agent, maintaining the temperature and stirring, and starting the timer after the vulcanizing agent is added until the reaction time reaches 5-20 min, then adding N-cyclohexylthiophthalimide, maintaining the temperature and stirring.

[0009] The reaction time is inversely proportional to the amount of vulcanizing agent added.

[0010] According to some preferred aspects of the present invention, the mass ratio of the butyl rubber, the vulcanizing agent and the N-cyclohexylthiophthalimide is 1:0.002-0.008:0.03-0.1.

[0011] According to some preferred aspects of the present invention, when the ratio of the amount of the vulcanizing agent added to the butyl rubber is greater than 0.005, the reaction time is less than or equal to 10 min.

[0012] According to some preferred aspects of the present invention, the butyl rubber raw materials, by weight, comprise: 100 parts of mixed rubber matrix, 0.5-5 parts of zinc stearate, 10-20 parts of tackifying resin, 0.5-5 parts of metal oxide, 5-20 parts of polyisobutylene, 1-10 parts of liquid paraffin, 0.1-1 parts of vulcanizing agent, and 2-8 parts of N-cyclohexylthiophthalimide; the mixed rubber matrix comprises butyl rubber and a flame retardant, wherein the mass ratio of butyl rubber to the flame retardant is 5-10:1.

[0013] According to some preferred aspects of the present invention, the butyl rubber has a particle size of 700-90 mesh.

[0014] According to some preferred aspects of the invention, the metal oxide is zinc oxide.

[0015] According to some preferred aspects of the invention, the tackifying resin is a terpene resin.

[0016] According to some preferred aspects of the invention, the flame retardant is magnesium hydroxide.

[0017] In some preferred embodiments of the present invention, the preparation of the butyl rubber includes:

[0018] After dehydrating and drying the butyl rubber raw material, crush and sieve it to collect the sieved rubber particles. Then, mix it with a flame retardant to obtain a mixed rubber matrix. Place the mixed rubber matrix in an extruder, control the extruder head temperature, keep it at a constant temperature to melt, then raise the temperature and keep it at a constant temperature while stirring. After the mixing is complete, add zinc stearate, tackifying resin, metal oxide, polyisobutylene, liquid paraffin, and vulcanizing agent to the extruder in sequence without interruption. After adding the vulcanizing agent for 5-20 minutes, add N-cyclohexylthiophthalimide and extrude to form the final product.

[0019] Furthermore, the temperature of the machine head is 110-120℃;

[0020] The heating rate is controlled to be 4-6℃ / min;

[0021] The temperature after the heating is controlled to be 135-160℃;

[0022] The outlet temperature of the extruder is controlled to be 145-165℃.

[0023] In some preferred and specific embodiments of the present invention, in the embodiment of preparing the butyl rubber, the die head temperature of the extruder is controlled at 110-115°C, and after being kept at this temperature for 35-40 minutes to melt, the temperature is then increased to 135-160°C at a rate of 4-6°C / min, and kept at this temperature for 15-20 minutes to stir. The total feeding time of the zinc stearate, the tackifying resin, the metal oxide, the polyisobutylene, the liquid paraffin, and the vulcanizing agent is 30-45 minutes. The mixing time after adding N-cyclohexylthiophthalimide is 5-30 minutes, and the mixture is then extruded and molded.

[0024] Another technical solution provided by the present invention: a butyl rubber prepared by the preparation method described above.

[0025] Another technical solution provided by the present invention is a waterproof membrane, comprising a membrane body and an adhesive coated on the membrane body, wherein the adhesive comprises the butyl rubber described above.

[0026] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0027] Based on the insufficient adhesive strength and susceptibility to interfacial damage of conventional butyl rubber adhesives in existing technologies, the inventors of this invention, through extensive experimentation and analysis, discovered that in the vulcanization system of this invention, the peel force between butyl rubber and the substrate to be bonded changes as the vulcanization process progresses. Moreover, this change is not linear, but rather an initial increase followed by a decrease. Based on this analysis, the inventors innovatively proposed that the butyl rubber undergo vulcanization during its preparation process, but primarily partial vulcanization, i.e., controlling the vulcanization progress. This allows the vulcanization of the butyl rubber to be stopped promptly within the range where the peel force is optimal. Consequently, the butyl rubber of this invention possesses both good mechanical properties and, when subjected to damage, primarily undergoes cohesive failure.

[0028] Furthermore, the preparation method of the present invention can be carried out during the normal extrusion process of butyl rubber without the need for additional equipment, and is well compatible with existing processes, thus having great potential for large-scale application. Detailed Implementation

[0029] The above-mentioned solution will be further described below with reference to specific embodiments; it should be understood that these embodiments are used to illustrate the basic principles, main features and advantages of the present invention, and the present invention is not limited to the scope of the following embodiments; the implementation conditions used in the embodiments can be further adjusted according to specific requirements, and the implementation conditions not specified are usually the conditions in conventional experiments.

[0030] Unless otherwise specified in the following examples, all raw materials are commercially available or prepared by conventional methods in the art.

[0031] In the following description, the butyl rubber was purchased from Lanxess, grade 301;

[0032] The terpene resin was purchased from Pinova, brand name A135;

[0033] Polyisobutylene was purchased from Daelim, grade PB1300;

[0034] The liquid paraffin was purchased from Xinglong New Materials, grade 68#.

[0035] The sulfur was purchased from Luchuan Petrochemical, grade S-80.

[0036] N-Cyclohexylthiophthalimide, abbreviated as CTP, was purchased from Zhiheng Zhiyuan, brand name CTP-01;

[0037] N,N'-Tetramethyldithiodisulfide carbonylamine, abbreviated as accelerator TMTD, was purchased from Xieda, brand name TMTD-106.

[0038] Example 1

[0039] Butyl rubber was placed in an oven at 50℃ and dried for 12 hours. After dehydration, the dried rubber was crushed, ground, and sieved. Rubber particles passing through an 800-mesh sieve were collected. The flame retardant was added to the rubber particles at a mass ratio of 1:7 and mixed to obtain a mixed rubber matrix. By weight, 100 parts of the mixed rubber matrix, 2.5 parts of zinc stearate, 15 parts of terpene resin, 2 parts of zinc oxide, 10 parts of polyisobutylene, 2 parts of liquid paraffin, 0.3 parts of sulfur, and 3 parts of CTP were weighed. The mixed rubber matrix was then placed in an extrusion press. In the machine, the extruder head temperature is controlled at 115℃, and after melting at this temperature for 35 minutes, the temperature is increased to 140℃ at a rate of 5℃ / min, and stirred at this temperature for 15 minutes. After the stirring and mixing are completed, zinc stearate, terpene resin, zinc oxide, polyisobutylene, liquid paraffin, and sulfur are added to the extruder in sequence and continuously, with the feeding time controlled at 35 minutes. After adding sulfur and mixing for 15 minutes, CTP is added and mixed for 15 minutes. The extruder screw speed is controlled at 25 r / min, and the outlet temperature is 155℃. The extrusion is then formed and butyl rubber is collected.

[0040] Example 2

[0041] Butyl rubber was placed in an oven at 50℃ and dried for 12 hours. After dehydration, the dried rubber was crushed, ground, and sieved. Rubber particles passing through an 800-mesh sieve were collected. The flame retardant was added to the rubber particles at a mass ratio of 1:7 and mixed to obtain a mixed rubber matrix. By weight, 100 parts of the mixed rubber matrix, 2.5 parts of zinc stearate, 15 parts of terpene resin, 2 parts of zinc oxide, 10 parts of polyisobutylene, 5 parts of liquid paraffin, 0.5 parts of sulfur, and 5 parts of CTP were weighed. The mixed rubber matrix was then placed in an extrusion press. In the machine, the extruder head temperature is controlled at 115℃, and after melting at this temperature for 35 minutes, the temperature is increased to 140℃ at a rate of 5℃ / min, and stirred at this temperature for 15 minutes. After the stirring and mixing are completed, zinc stearate, terpene resin, zinc oxide, polyisobutylene, liquid paraffin, and sulfur are added to the extruder in sequence and continuously, with the feeding time controlled at 35 minutes. After adding sulfur and mixing for 8 minutes, CTP is added and mixed for 15 minutes. The extruder screw speed is controlled at 25 r / min, and the outlet temperature is 155℃. The extrusion is then formed and butyl rubber is collected.

[0042] Example 3

[0043] Butyl rubber was placed in an oven at 50℃ and dried for 12 hours. After dehydration, the dried rubber was crushed, ground, and sieved. Rubber particles passing through an 800-mesh sieve were collected. The flame retardant was added to the rubber particles at a mass ratio of 1:7 and mixed to obtain a mixed rubber matrix. By weight, 100 parts of the mixed rubber matrix, 2.5 parts of zinc stearate, 15 parts of terpene resin, 2 parts of zinc oxide, 10 parts of polyisobutylene, 5 parts of liquid paraffin, 0.2 parts of sulfur, 0.3 parts of accelerator TMTD, and 5 parts of CTP were weighed. The mixed rubber matrix was then placed in an extruder. The extruder head temperature was controlled at 115℃. After melting at this temperature for 35 minutes, the temperature was increased to 140℃ at a rate of 5℃ / min. The temperature was then maintained and stirred for 15 minutes. After the mixture was stirred, zinc stearate, terpene resin, zinc oxide, polyisobutylene, liquid paraffin, sulfur, and accelerator TMTD were added to the extruder in sequence and continuously. The feeding time was controlled at 35 minutes. After adding sulfur and accelerator TMTD and mixing for 15 minutes, CTP was added and mixed for 15 minutes. The screw speed of the extruder was controlled at 25 r / min and the outlet temperature was 155℃. The extrusion was then formed and the butyl rubber was collected.

[0044] Comparative Example 1

[0045] Butyl rubber was placed in an oven at 50℃ and dried for 12 hours. After dehydration, the dried rubber was crushed, ground, and sieved. The rubber particles that passed through an 800-mesh sieve were collected. Flame retardant was added to the rubber particles at a mass ratio of 1:7 and mixed to obtain a mixed rubber matrix. By weight, 100 parts of the mixed rubber matrix, 2.5 parts of zinc stearate, 15 parts of terpene resin, 2 parts of zinc oxide, 10 parts of polyisobutylene, and 2 parts of liquid paraffin were weighed. The mixed rubber matrix was then placed... In the extruder, the extruder head temperature is controlled at 115℃. After melting at this temperature for 35 minutes, the temperature is increased to 140℃ at a rate of 5℃ / min. The temperature is then maintained and stirred for 15 minutes. After the mixture is fully stirred, zinc stearate, terpene resin, zinc oxide, polyisobutylene, and liquid paraffin are added to the extruder sequentially and continuously. The feeding time is controlled at 30 minutes, and the extruder screw speed is controlled at 25 r / min. The outlet temperature is 155℃. The extrusion is then formed, and the non-vulcanized butyl rubber is collected.

[0046] Comparative Example 2

[0047] Butyl rubber was placed in an oven at 50℃ and dried for 12 hours. After dehydration, the dried rubber was crushed, ground, and sieved. Rubber particles passing through an 800-mesh sieve were collected. The flame retardant was added to the rubber particles at a mass ratio of 1:7 and mixed to obtain a mixed rubber matrix. By weight, 100 parts of the mixed rubber matrix, 2.5 parts of zinc stearate, 15 parts of terpene resin, 2 parts of zinc oxide, 10 parts of polyisobutylene, 2 parts of liquid paraffin, and 0.3 parts of sulfur were weighed. The mixed rubber matrix was then placed... In the extruder, the extruder head temperature is controlled at 115℃, and after melting at this temperature for 35 minutes, the temperature is increased to 140℃ at a rate of 5℃ / min, and stirred at this temperature for 15 minutes. After the mixture is stirred, zinc stearate, terpene resin, zinc oxide, polyisobutylene, liquid paraffin, and sulfur are added to the extruder sequentially and continuously, with the feeding time controlled at 35 minutes. Sulfur is added and mixed for 15 minutes. The extruder screw speed is controlled at 25 r / min, and the outlet temperature is 155℃. The mixture is then extruded and collected to obtain vulcanized butyl rubber.

[0048] Comparative Example 3

[0049] Butyl rubber was placed in an oven at 50℃ and dried for 12 hours. After dehydration, the dried rubber was crushed, ground, and sieved. Rubber particles passing through an 800-mesh sieve were collected. The flame retardant was added to the rubber particles at a mass ratio of 1:7 and mixed to obtain a mixed rubber matrix. By weight, 100 parts of the mixed rubber matrix, 2.5 parts of zinc stearate, 15 parts of terpene resin, 2 parts of zinc oxide, 10 parts of polyisobutylene, 2 parts of liquid paraffin, and 1 part of sulfur were weighed. The mixed rubber matrix was then placed in… In the extruder, the extruder head temperature is controlled at 115℃. After melting at this temperature for 35 minutes, the temperature is increased to 140℃ at a rate of 5℃ / min. The temperature is then maintained and stirred for 15 minutes. After the mixture is stirred, zinc stearate, terpene resin, zinc oxide, polyisobutylene, liquid paraffin, and sulfur are added to the extruder sequentially and continuously. The feeding time is controlled at 35 minutes. Sulfur is added and mixed for 15 minutes. The extruder screw speed is controlled at 25 r / min, and the outlet temperature is 155℃. The extrusion is then formed, and the vulcanized butyl rubber is collected.

[0050] Comparative Example 4

[0051] Butyl rubber was placed in an oven at 50℃ and dried for 12 hours. After dehydration, the dried rubber was crushed, ground, and sieved. Rubber particles passing through an 800-mesh sieve were collected. The flame retardant was added to the rubber particles at a mass ratio of 1:7 and mixed to obtain a mixed rubber matrix. By weight, 100 parts of the mixed rubber matrix, 2.5 parts of zinc stearate, 15 parts of terpene resin, 2 parts of zinc oxide, 10 parts of polyisobutylene, 2 parts of liquid paraffin, 0.5 parts of sulfur, and 0.5 parts of accelerator TMTD were weighed. The mixed rubber matrix was then placed in an extrusion press. In the machine, the extruder head temperature is controlled at 115℃, and after being kept at this temperature for 35 minutes, the temperature is increased to 140℃ at a rate of 5℃ / min, and then kept at this temperature and stirred for 15 minutes. After the stirring and mixing are completed, zinc stearate, terpene resin, zinc oxide, polyisobutylene, liquid paraffin, sulfur, and accelerator TMTD are added to the extruder in sequence without interruption, and the feeding time is controlled at 35 minutes. After adding sulfur and accelerator TMTD, the mixture is mixed for 15 minutes and the extruder screw speed is controlled at 25 r / min. The outlet temperature is 155℃, and the extrusion is formed and collected to obtain vulcanized butyl rubber.

[0052] Comparative Example 5

[0053] Butyl rubber was placed in an oven at 50℃ and dried for 12 hours. After dehydration, the dried rubber was crushed, ground, and sieved. The rubber particles that passed through an 800-mesh sieve were collected. Flame retardant was added to the rubber particles at a mass ratio of 1:7 and mixed to obtain a mixed rubber matrix. By weight, 100 parts of the mixed rubber matrix, 2.5 parts of zinc stearate, 15 parts of terpene resin, 2 parts of zinc oxide, 10 parts of polyisobutylene, 2 parts of liquid paraffin, and 0.03 parts of sulfur were weighed. The mixed rubber matrix was then placed in an extruder. In the process, the extruder head temperature is controlled at 110℃, and after melting at this temperature for 35 minutes, the temperature is increased to 135℃ at a rate of 5℃ / min, and stirred at this temperature for 15 minutes. After the mixture is stirred, zinc stearate, terpene resin, zinc oxide, polyisobutylene, liquid paraffin, and sulfur are added to the extruder in sequence and continuously, with the feeding time controlled at 35 minutes. Sulfur is added and mixed for 15 minutes. The extruder screw speed is controlled at 25 r / min, and the outlet temperature is 155℃. The extrusion is then formed, and the vulcanized butyl rubber is collected.

[0054] Comparative Example 6

[0055] Butyl rubber was placed in an oven at 50℃ and dried for 12 hours. After dehydration, the dried rubber was crushed, ground, and sieved. Rubber particles passing through an 800-mesh sieve were collected. The flame retardant was added to the rubber particles at a mass ratio of 1:7 and mixed to obtain a mixed rubber matrix. By weight, 100 parts of the mixed rubber matrix, 2.5 parts of zinc stearate, 15 parts of terpene resin, 2 parts of zinc oxide, 10 parts of polyisobutylene, 2 parts of liquid paraffin, 0.5 parts of sulfur, and 5 parts of CTP were weighed. The mixed rubber matrix was then placed in an extrusion press. In the machine, the extruder head temperature is controlled at 115℃, and after melting at this temperature for 35 minutes, the temperature is increased to 140℃ at a rate of 5℃ / min, and stirred at this temperature for 15 minutes. After the stirring and mixing are completed, zinc stearate, terpene resin, zinc oxide, polyisobutylene, liquid paraffin, and sulfur are added to the extruder in sequence and continuously, with the feeding time controlled at 35 minutes. After adding sulfur and mixing for 30 minutes, CTP is added and mixed for 15 minutes. The extruder screw speed is controlled at 25 r / min, and the outlet temperature is 155℃. The extrusion is then formed and butyl rubber is collected.

[0056] Comparative Example 7

[0057] Butyl rubber was placed in an oven at 50℃ and dried for 12 hours. After dehydration, the dried rubber was crushed, ground, and sieved. Rubber particles passing through an 800-mesh sieve were collected. The flame retardant was added to the rubber particles at a mass ratio of 1:7 and mixed to obtain a mixed rubber matrix. By weight, 100 parts of the mixed rubber matrix, 2.5 parts of zinc stearate, 15 parts of terpene resin, 2 parts of zinc oxide, 10 parts of polyisobutylene, 2 parts of liquid paraffin, 0.5 parts of sulfur, and 5 parts of CTP were weighed. The mixed rubber matrix was then placed in an extrusion press. In the machine, the extruder head temperature is controlled at 115℃, and after melting at this temperature for 35 minutes, the temperature is increased to 140℃ at a rate of 5℃ / min, and stirred at this temperature for 15 minutes. After the stirring and mixing are completed, zinc stearate, terpene resin, zinc oxide, polyisobutylene, liquid paraffin, and sulfur are added to the extruder in sequence and continuously, with the feeding time controlled at 35 minutes. After adding sulfur and mixing for 3 minutes, CTP is added and mixed for 15 minutes. The extruder screw speed is controlled at 25 r / min, and the outlet temperature is 155℃. The extrusion is then formed, and butyl rubber is collected.

[0058] Compared with Example 1, the comparative examples above are as follows: Comparative Example 1 did not add a vulcanizing agent; Comparative Examples 2, 3, 4, and 5 added different amounts of vulcanizing agent and did not add CTP; Comparative Example 6 had a prolonged reaction time after adding sulfur and added CTP; and Comparative Example 7 had a significantly shortened reaction time after adding sulfur and added CTP.

[0059] After extrusion, the butyl rubber of Examples 1-3 and Comparative Examples 1-7 was uniformly coated onto a 0.8 mm thick TPO sheet, with a rubber layer thickness of 0.4 mm, to obtain a roll material. After cooling for 24 hours, it can be tested.

[0060] Test section

[0061] Peel strength test between coils and peel strength test with color steel sheet: The test shall be conducted in accordance with the method specified in JC / T 942-2004.

[0062] The roll materials of Examples 1-3 and Comparative Examples 1-7 were subjected to relevant performance tests, and the test results are shown in Tables 1 and 2 below.

[0063] Table 1

[0064]

[0065]

[0066] Table 2

[0067]

[0068] The test results above show that in Examples 1-3, when the rolls were subjected to peel tests, the adhesive layer was prone to cohesive failure under external force. Compared with the non-vulcanized butyl rubber in Comparative Example 1, the peel strength between rolls and between the rolls and the color steel plate was significantly improved. This is likely due to the presence of a certain cross-linking structure within the butyl rubber layer, which improves the overall mechanical properties of the adhesive layer. Meanwhile, Comparative Examples 2-4 show that when only a vulcanizing agent was added without CTP, the adhesive layer underwent interfacial failure under external force during the peel test. This is likely because the vulcanization process was not controlled, resulting in excessively high cross-linking of the rubber macromolecules within the adhesive layer and excessively high inter-layer forces. When subjected to external force, the intermolecular forces between rubber molecules are much greater than the interfacial forces between the rubber layer and the sheet, resulting in interfacial damage and low peel strength. As can be seen from Comparative Example 5, reducing the amount of vulcanizing agent without controlling the vulcanization progress through CTP does not improve the peel strength of the material. This is because when the amount of vulcanizing agent is very small, the crosslinking reaction does not occur or the vulcanizing agent is not dispersed throughout the material, leading to localized vulcanization. As can be seen from Comparative Examples 6 and 7, under the vulcanization system of the present invention, with the addition of a CTP inhibitor after the vulcanization time, both excessively short and excessively long vulcanization times are detrimental to improving peel strength.

[0069] In summary, after adding an appropriate amount of vulcanizing agent to butyl rubber and allowing it to vulcanize for a suitable time, CTP is added. CTP can rapidly react with the sulfur bonds of the vulcanizing agent in the system, deactivating it and thus controlling the overall degree of vulcanization. This micro-vulcanized butyl rubber system exhibits superior mechanical and adhesive properties compared to non-vulcanized butyl rubber systems and vulcanized butyl rubber systems without vulcanization inhibitors. Furthermore, this preparation method has low equipment requirements, is highly compatible with existing processes, and has great potential for large-scale application.

[0070] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

[0071] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise 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 the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

Claims

1. A method for preparing butyl rubber, characterized in that, The raw materials for the butyl rubber include butyl rubber, a vulcanizing agent, and N-cyclohexylthiophthalimide. The vulcanizing agent includes sulfur and selective N,N'-tetramethyldithiocarbonylamine. The mass ratio of the butyl rubber, the vulcanizing agent, and the N-cyclohexylthiophthalimide is 1:0.001-0.01:0.015-0.

2. The preparation method of this butyl rubber includes: melting butyl rubber under heating and stirring conditions, then adding a vulcanizing agent, maintaining the temperature and stirring, and starting the timer after the vulcanizing agent is added until the reaction time reaches 5-20 min, then adding N-cyclohexylthiophthalimide, maintaining the temperature and stirring. The reaction time is inversely proportional to the amount of vulcanizing agent added. When the ratio of the amount of vulcanizing agent added to the butyl rubber is greater than 0.005, the reaction time is less than or equal to 10 min.

2. The method for preparing butyl rubber according to claim 1, characterized in that, The mass ratio of the butyl rubber, the vulcanizing agent, and the N-cyclohexylthiophthalimide is 1:0.002-0.008:0.03-0.

1.

3. The method for preparing butyl rubber according to claim 1, characterized in that, By weight, the raw materials of the butyl rubber include: 100 parts of mixed rubber matrix, 0.5-5 parts of zinc stearate, 10-20 parts of tackifying resin, 0.5-5 parts of metal oxide, 5-20 parts of polyisobutylene, 1-10 parts of liquid paraffin, 0.1-0.5 parts of vulcanizing agent, and 2-8 parts of N-cyclohexylthiophthalimide; the mixed rubber matrix includes butyl rubber and flame retardant, and the mass ratio of butyl rubber to flame retardant is 5-10:

1.

4. The method for preparing butyl rubber according to claim 3, characterized in that, The butyl rubber has a particle size of 700-90 mesh, the metal oxide is zinc oxide, the tackifying resin is terpene resin, and the flame retardant is magnesium hydroxide.

5. The method for preparing butyl rubber according to claim 3, characterized in that, The methods for preparing this butyl rubber include: After dehydrating and drying the butyl rubber raw material, crush and sieve it to collect the sieved rubber particles. Then, mix it with a flame retardant to obtain a mixed rubber matrix. Place the mixed rubber matrix in an extruder, control the extruder head temperature, keep it at a constant temperature to melt, then raise the temperature and keep it at a constant temperature while stirring. After the mixing is complete, add zinc stearate, tackifying resin, metal oxide, polyisobutylene, liquid paraffin, and vulcanizing agent to the extruder in sequence without interruption. After adding the vulcanizing agent for 5-20 minutes, add N-cyclohexylthiophthalimide and extrude to form the final product.

6. The method for preparing butyl rubber according to claim 5, characterized in that, The temperature of the machine head is 110-120℃; The heating rate is controlled to be 4-6℃ / min; The temperature after the heating is controlled to be 135-160℃; The outlet temperature of the extruder is controlled to be 145-165℃.

7. The method for preparing butyl rubber according to claim 5, characterized in that, In the embodiment of preparing this butyl rubber, the die head temperature of the extruder is controlled at 110-115℃, and after melting at this temperature for 35-40 minutes, the temperature is increased to 135-160℃ at a rate of 4-6℃ / min, and stirred at this temperature for 15-20 minutes. The total feeding time of the zinc stearate, the tackifying resin, the metal oxide, the polyisobutylene, the liquid paraffin, and the vulcanizing agent is 30-45 minutes. The mixing time after adding N-cyclohexylthiophthalimide is 5-30 minutes, and the mixture is then extruded and molded.

8. A butyl rubber prepared by the preparation method according to any one of claims 1-7.

9. A waterproof membrane comprising a membrane body and an adhesive coated on the membrane body, characterized in that, The adhesive comprises the butyl rubber as described in claim 8.

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