Method for modifying butyl rubber by adopting maleic anhydride

Abstract

The invention belongs to the technical field of rubber manufacturing, and discloses a method for modifying butyl rubber by adopting maleic anhydride, which comprises the following steps: S1, preparing materials; s2, preparing equipment; s3, weighing the raw materials; s4, performing pretreatment; s5, performing initial mixing; s6, adding maleic anhydride; s7, adding a cross-linking agent and an accelerant; s8, adding an antioxidant; s9, vulcanization preparation; s10, a vulcanization process; s11, cooling and demolding are conducted; and S12, physical performance testing. According to the invention, deformation or fracture is not easy to occur, so that the application range is widened. The modified butyl rubber keeps good elasticity and flexibility under the low-temperature condition, the problems that traditional butyl rubber becomes brittle and loses elasticity at the low temperature are solved, meanwhile, by optimizing the vulcanization condition and adding the antioxidant, the method further remarkably improves the heat aging resistance of the butyl rubber, and the service life of the butyl rubber is prolonged. Therefore, the service life of the high-temperature-resistant rubber is prolonged when the high-temperature-resistant rubber is used for a long time, and performance reduction caused by softening and aging is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of rubber manufacturing, and specifically relates to a method for modifying butyl rubber by using maleic anhydride. Background Art

[0002] Butyl rubber is a type of synthetic rubber, which is produced by cationic polymerization of isobutylene and a small amount of isoprene under the action of a catalyst (such as aluminum chloride). The highly saturated structure of the butyl rubber molecular chain makes it highly chemically stable, resistant to acid, alkali, oxidation and reduction, and especially resistant to animal and vegetable oils. Although it is not resistant to concentrated oxidizing acids, such as nitric acid and sulfuric acid, it is resistant to non-oxidizing acids and oxidizing acids of medium concentration, and is resistant to alkaline solutions and redox solutions. With its unique physical and chemical properties and a wide range of applications, butyl rubber occupies an important position in the rubber industry.

[0003] However, conventional butyl rubber still has certain shortcomings when used. For example, although butyl rubber has good air tightness and aging resistance, its wear resistance is relatively low and it is not suitable for high-wear application environments. The processing performance of butyl rubber is relatively poor, especially at high temperatures, it is easy to stick to the mold, which may lead to molding difficulties. When subjected to large tension or compression, the strength of butyl rubber is insufficient and it is easy to deform or crack. Under low temperature conditions, butyl rubber may become brittle and lose elasticity, affecting its application effect. At high temperatures, long-term use may lead to performance degradation, causing softening and aging. Summary of the invention

[0004] The object of the present invention is to provide a method for modifying butyl rubber using maleic anhydride to solve the problems raised in the above background technology.

[0005] In order to achieve the above object, the present invention provides the following technical solution: a method for modifying butyl rubber using maleic anhydride, comprising the following steps:

[0006] S1: Material preparation;

[0007] S2: Equipment preparation;

[0008] S3: weighing raw materials;

[0009] S4: pre-processing;

[0010] S5: initial mixing;

[0011] S6: adding maleic anhydride;

[0012] S7: adding crosslinking agent and accelerator;

[0013] S8: Add antioxidants;

[0014] S9: Preparation for vulcanization;

[0015] S10: vulcanization process;

[0016] S11: cooling and demoulding;

[0017] S12: Physical properties test;

[0018] The material preparation includes preparing the following materials: butyl rubber (IIR), maleic anhydride (MAH), hydrogenated nitrile rubber (HNBR), a crosslinking agent (sulfur), an accelerator (MBTS), a filler (carbon black N330), and an antioxidant (TMQ).

[0019] As a further technical solution of the present invention, the butyl rubber accounts for 66.6% of the total materials, the maleic anhydride accounts for 4.7% of the total materials, the hydrogenated nitrile rubber accounts for 10.0% of the total materials, the cross-linking agent accounts for 1.0% of the total materials, the accelerator accounts for 0.5% of the total materials, the filler accounts for 16.6% of the total materials, and the antioxidant accounts for 0.7% of the total materials.

[0020] This formula aims to optimize the comprehensive performance of rubber materials by precisely controlling the ratio of key components such as butyl rubber, maleic anhydride, and hydrogenated nitrile rubber. As a basic material, butyl rubber provides excellent air tightness and aging resistance; the introduction of maleic anhydride is intended to improve the polarity of rubber and enhance adhesion with other materials; hydrogenated nitrile rubber improves the heat resistance and oil resistance of the material. The addition of crosslinking agents, accelerators, fillers, and antioxidants further enhances the strength, hardness, and durability of the rubber.

[0021] As a further technical solution of the present invention, the equipment preparation includes preparing the following equipment: a mixing machine, a vulcanization mold, a vulcanization furnace, a thermometer, a weighing instrument, and a stirrer.

[0022] The key equipment covered in the equipment preparation stage, such as mixers, vulcanization molds, and vulcanization furnaces, play a vital role in the production process of maleic anhydride modified butyl rubber. They are responsible for the uniform mixing of raw materials, molding and curing, while thermometers, weighing instruments, and agitators ensure the precise control of the production process and the full reaction of raw materials, jointly guaranteeing product quality and production efficiency.

[0023] As a further technical solution of the present invention, the raw material weighing includes weighing each material according to the material ratio, using an electronic scale to weigh the materials, and recording the weight of each raw material. The pretreatment includes heating the mixer to 70-80°C, preheating for 15 minutes, and ensuring temperature stability.

[0024] The raw material weighing process ensures that the various raw materials in the production of maleic anhydride modified butyl rubber are accurately proportioned. The electronic scale is used to weigh and record the weight, which provides a basic guarantee for the subsequent mixing and vulcanization process. In the pretreatment stage, the mixer is heated to a suitable temperature and preheated to ensure uniform heating and full reaction of the raw materials during the mixing process, laying a solid foundation for the production of high-quality rubber products.

[0025] As a further technical solution of the present invention, the initial mixing includes placing butyl rubber into a mixer, adding hydrogenated nitrile rubber and carbon black, stirring at a relatively low speed for 5 minutes, increasing the speed after the mixture is evenly mixed, and continuing to mix for 5 minutes to ensure even dispersion.

[0026] The initial mixing step is crucial in the preparation of maleic anhydride modified butyl rubber. By adding butyl rubber, hydrogenated nitrile rubber and carbon black to the mixer in a specific order and stirring at different speeds, the initial uniform mixing and good dispersion of the raw materials are ensured. This step provides a uniform matrix for the subsequent addition of modifiers such as maleic anhydride, and is a key link in ensuring the quality of the final product.

[0027] As a further technical solution of the present invention, the adding of maleic anhydride includes slowly adding maleic anhydride, and the maleic anhydride may be heated to about 50°C to reduce viscosity. The mixing is continued for 10-15 minutes to ensure uniform dispersion, and the rotation speed is adjusted if necessary to optimize the dispersion effect. The adding of the crosslinking agent and the accelerator includes adding sulfur and the accelerator, and continuing to mix at a medium speed for about 5 minutes to ensure uniform distribution of the crosslinking agent and the accelerator. The adding of the antioxidant includes adding the antioxidant, and mixing at a low speed for 3-5 minutes to ensure complete mixing to avoid degradation of the antioxidant caused by high temperature.

[0028] The steps of adding maleic anhydride, crosslinking agent, accelerator and antioxidant are the core links in the production of maleic anhydride modified butyl rubber. The viscosity of maleic anhydride is reduced by heating and slowly added to ensure its uniform dispersion in the rubber matrix, which improves the polarity and adhesion of the rubber. Subsequently, crosslinking agents and accelerators are added to promote the crosslinking reaction between rubber molecules and enhance the strength of the rubber. Finally, antioxidants are added to protect the rubber from oxidative degradation and extend its service life. The precise execution of these steps together ensures the excellent performance and stability of the modified butyl rubber.

[0029] As a further technical solution of the present invention, the vulcanization preparation takes out the mixed rubber material and quickly transfers it to the vulcanization mold. A scraper or spatula can be used to help fill the mold. The vulcanization process includes placing the mold in a vulcanization furnace, setting the temperature to 150°C, and the vulcanization time to 20 minutes, ensuring that the temperature in the furnace is evenly distributed, and the temperature can be checked regularly if necessary.

[0030] Vulcanization preparation and vulcanization process are key steps to transform a well-mixed rubber compound into a rubber product with stable structure and performance. By quickly filling the rubber compound into the vulcanization mold and vulcanizing it in the vulcanization furnace at a suitable temperature and time, sufficient cross-linking between rubber molecules is ensured, thereby improving the strength, hardness and durability of the rubber.

[0031] As a further technical solution of the present invention, the cooling and demoulding include taking out the mold from the vulcanization furnace and cooling it naturally to room temperature to avoid deformation of the product due to rapid cooling. The mold must be demoulded carefully. If there is adhesion, it can be gently pried with appropriate tools.

[0032] Cooling and demoulding are the finishing steps in the production of rubber products, which are crucial to product quality. Natural cooling to room temperature can avoid product deformation caused by rapid cooling, ensuring the dimensional stability and internal structural integrity of rubber products. Careful demoulding can prevent product damage, and using appropriate tools to deal with adhesion problems can further ensure the yield rate and appearance quality of rubber products.

[0033] As a further technical solution of the present invention, the physical property test includes a hardness test, a tensile strength test, a tear strength test, and an aging resistance test. The hardness test needs to use a Shore A hardness tester to record the hardness value, the tensile strength test needs to use a tensile testing machine to record the breaking strength and elongation, the tear strength test needs to record the tear strength value, and the aging resistance test needs to be carried out in a high temperature and high humidity environment to accelerate the aging test.

[0034] Physical property testing is a key link in evaluating the quality of maleic anhydride modified butyl rubber products. Through hardness testing, tensile strength testing, tear strength testing and aging resistance testing, we can fully understand the key indicators of rubber products such as hardness, strength, toughness and aging resistance. These tests not only ensure that rubber products meet design requirements, but also provide a scientific basis for their reliability and durability in various application scenarios. They are an important means to improve the quality and market competitiveness of rubber products.

[0035] The beneficial effects of the present invention are as follows:

[0036] 1. The present invention effectively improves the wear resistance of butyl rubber by introducing maleic anhydride as a modifier, so that it can maintain a longer service life in a high-wear application environment. At the same time, the addition of maleic anhydride also enhances the processing performance of butyl rubber, especially at high temperatures, effectively reduces the sticking phenomenon, reduces the difficulty of molding, and improves production efficiency. The mechanical strength of butyl rubber is further improved by accurately controlling the ratio of each raw material and the vulcanization process. When subjected to large tension or compression, the modified butyl rubber shows higher strength and toughness, and is not prone to deformation or cracking, thereby broadening its application range. Under low temperature conditions, the modified butyl rubber also maintains good elasticity and flexibility, avoiding the problem of traditional butyl rubber becoming brittle and losing elasticity at low temperatures. At the same time, by optimizing the vulcanization conditions and adding antioxidants, the method also significantly improves the heat aging resistance of butyl rubber, prolongs its service life when used for a long time at high temperatures, and reduces the performance degradation caused by softening and aging.

[0037] 2. The present invention successfully prepared maleic anhydride modified butyl rubber with excellent performance through fine raw material ratio and rigorous process flow. The method not only focuses on improving the basic performance of butyl rubber, but also makes targeted improvements for its specific needs in practical applications. For example, in the raw material ratio, by introducing fillers such as hydrogenated nitrile rubber and carbon black, the hardness and wear resistance of the modified butyl rubber are effectively enhanced, making it more suitable for application scenarios with high requirements for hardness and wear resistance. The aging resistance of the modified butyl rubber is further improved by optimizing the vulcanization process and adding antioxidants. In harsh environments such as high temperature and high humidity, the modified butyl rubber can maintain a longer service life and more stable performance, thereby reducing the replacement cost and maintenance cost caused by material aging. By accurately controlling the parameters and conditions of each step, the quality stability and production repeatability of the modified butyl rubber can be ensured. At the same time, the equipment and raw materials used are relatively common and easy to obtain, which reduces the production cost and technical threshold, and is conducive to the promotion and application of the method. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a block diagram of the overall system of the present invention. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] like Figure 1As shown, in an embodiment of the present invention, a method for modifying butyl rubber using maleic anhydride comprises the following steps:

[0041] S1: Material preparation;

[0042] S2: Equipment preparation;

[0043] S3: weighing raw materials;

[0044] S4: pre-processing;

[0045] S5: initial mixing;

[0046] S6: adding maleic anhydride;

[0047] S7: adding crosslinking agent and accelerator;

[0048] S8: Add antioxidants;

[0049] S9: Preparation for vulcanization;

[0050] S10: vulcanization process;

[0051] S11: cooling and demoulding;

[0052] S12: Physical properties test;

[0053] Material preparation includes preparing the following materials: butyl rubber (IIR), maleic anhydride (MAH), hydrogenated nitrile rubber (HNBR), crosslinking agent (sulfur), accelerator (MBTS), filler (carbon black N330), and antioxidant (TMQ).

[0054] Among them, butyl rubber accounts for 66.6% of the total materials, maleic anhydride accounts for 4.7% of the total materials, hydrogenated nitrile rubber accounts for 10.0% of the total materials, cross-linking agents account for 1.0% of the total materials, accelerators account for 0.5% of the total materials, fillers account for 16.6% of the total materials, and antioxidants account for 0.7% of the total materials.

[0055] This formula aims to optimize the comprehensive performance of rubber materials by precisely controlling the ratio of key components such as butyl rubber, maleic anhydride, and hydrogenated nitrile rubber. As a basic material, butyl rubber provides excellent air tightness and aging resistance; the introduction of maleic anhydride is intended to improve the polarity of rubber and enhance adhesion with other materials; hydrogenated nitrile rubber improves the heat resistance and oil resistance of the material. The addition of crosslinking agents, accelerators, fillers, and antioxidants further enhances the strength, hardness, and durability of the rubber.

[0056] Among them, equipment preparation includes preparing the following equipment: mixer, vulcanization mold, vulcanization furnace, thermometer, weighing instrument, and agitator.

[0057] The key equipment covered in the equipment preparation stage, such as mixers, vulcanization molds, and vulcanization furnaces, play a vital role in the production process of maleic anhydride modified butyl rubber. They are responsible for the uniform mixing of raw materials, molding and curing, while thermometers, weighing instruments, and agitators ensure the precise control of the production process and the full reaction of raw materials, jointly guaranteeing product quality and production efficiency.

[0058] Among them, raw material weighing includes weighing each material according to the material ratio, using an electronic scale to weigh the materials, and recording the weight of each raw material. Pretreatment includes heating the mixer to 70-80°C, preheating for 15 minutes, and ensuring temperature stability.

[0059] The raw material weighing process ensures that the various raw materials in the production of maleic anhydride modified butyl rubber are accurately proportioned. The electronic scale is used to weigh and record the weight, which provides a basic guarantee for the subsequent mixing and vulcanization process. In the pretreatment stage, the mixer is heated to a suitable temperature and preheated to ensure uniform heating and full reaction of the raw materials during the mixing process, laying a solid foundation for the production of high-quality rubber products.

[0060] The initial mixing includes putting butyl rubber into a mixer, adding hydrogenated nitrile rubber and carbon black, stirring at a low speed for 5 minutes, increasing the speed after the mixture is evenly mixed, and continuing to mix for 5 minutes to ensure even dispersion.

[0061] The initial mixing step is crucial in the preparation of maleic anhydride modified butyl rubber. By adding butyl rubber, hydrogenated nitrile rubber and carbon black to the mixer in a specific order and stirring at different speeds, the initial uniform mixing and good dispersion of the raw materials are ensured. This step provides a uniform matrix for the subsequent addition of modifiers such as maleic anhydride, and is a key link in ensuring the quality of the final product.

[0062] Wherein, adding maleic anhydride includes slowly adding maleic anhydride, and the maleic anhydride may be heated to about 50°C to reduce viscosity. Mixing is continued for 10-15 minutes to ensure uniform dispersion, and the speed is adjusted if necessary to optimize the dispersion effect. Adding a crosslinking agent and an accelerator includes adding sulfur and an accelerator, and mixing at a medium speed for about 5 minutes to ensure uniform distribution of the crosslinking agent and the accelerator. Adding an antioxidant includes adding an antioxidant, and mixing at a low speed for 3-5 minutes to ensure complete mixing to avoid degradation of the antioxidant caused by high temperature.

[0063] The steps of adding maleic anhydride, crosslinking agent, accelerator and antioxidant are the core links in the production of maleic anhydride modified butyl rubber. The viscosity of maleic anhydride is reduced by heating and slowly added to ensure its uniform dispersion in the rubber matrix, which improves the polarity and adhesion of the rubber. Subsequently, crosslinking agents and accelerators are added to promote the crosslinking reaction between rubber molecules and enhance the strength of the rubber. Finally, antioxidants are added to protect the rubber from oxidative degradation and extend its service life. The precise execution of these steps together ensures the excellent performance and stability of the modified butyl rubber.

[0064] Among them, the vulcanization preparation takes out the mixed rubber and quickly transfers it to the vulcanization mold. A scraper or spatula can be used to help fill the mold. The vulcanization process includes placing the mold in a vulcanization furnace, setting the temperature to 150°C and the vulcanization time to 20 minutes. Ensure that the temperature in the furnace is evenly distributed. Check the temperature regularly if necessary.

[0065] Vulcanization preparation and vulcanization process are key steps to transform a well-mixed rubber compound into a rubber product with stable structure and performance. By quickly filling the rubber compound into the vulcanization mold and vulcanizing it in the vulcanization furnace at a suitable temperature and time, sufficient cross-linking between rubber molecules is ensured, thereby improving the strength, hardness and durability of the rubber.

[0066] Among them, cooling and demolding include taking the mold out of the vulcanization furnace and cooling it naturally to room temperature to avoid deformation of the product due to rapid cooling. The mold must be demolded carefully. If there is adhesion, use appropriate tools to pry it gently.

[0067] Cooling and demoulding are the finishing steps in the production of rubber products, which are crucial to product quality. Natural cooling to room temperature can avoid product deformation caused by rapid cooling, ensuring the dimensional stability and internal structural integrity of rubber products. Careful demoulding can prevent product damage, and using appropriate tools to deal with adhesion problems can further ensure the yield rate and appearance quality of rubber products.

[0068] Among them, physical property tests include hardness test, tensile strength test, tear strength test, and aging resistance test. The hardness test requires the use of a Shore A hardness tester to record the hardness value. The tensile strength test requires the use of a tensile testing machine to record the breaking strength and elongation. The tear strength test requires recording the tear strength value. The aging resistance test needs to be carried out in a high temperature and high humidity environment and accelerated aging test.

[0069] Physical property testing is a key link in evaluating the quality of maleic anhydride modified butyl rubber products. Through hardness testing, tensile strength testing, tear strength testing and aging resistance testing, we can fully understand the key indicators of rubber products such as hardness, strength, toughness and aging resistance. These tests not only ensure that rubber products meet design requirements, but also provide a scientific basis for their reliability and durability in various application scenarios. They are an important means to improve the quality and market competitiveness of rubber products.

[0070] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for modifying butyl rubber using maleic anhydride, comprising the following steps: S1: Material preparation; S2: Equipment preparation; S3: weighing raw materials; S4: pre-processing; S5: initial mixing; S6: adding maleic anhydride; S7: adding crosslinking agent and accelerator; S8: Add antioxidants; S9: Preparation for vulcanization; S10: vulcanization process; S11: cooling and demoulding; S12: Physical properties test; The material preparation includes preparing the following materials: butyl rubber (IIR), maleic anhydride (MAH), hydrogenated nitrile rubber (HNBR), a crosslinking agent (sulfur), an accelerator (MBTS), a filler (carbon black N330), and an antioxidant (TMQ).

2. The method of modifying butyl rubber using maleic anhydride according to claim 1, characterized in that: The butyl rubber accounts for 66.6% of the total materials, the maleic anhydride accounts for 4.7% of the total materials, the hydrogenated nitrile rubber accounts for 10.0% of the total materials, the cross-linking agent accounts for 1.0% of the total materials, the accelerator accounts for 0.5% of the total materials, the filler accounts for 16.6% of the total materials, and the antioxidant accounts for 0.7% of the total materials.

3. The method of modifying butyl rubber using maleic anhydride according to claim 1, characterized in that: The equipment preparation includes preparing the following equipment: a mixer, a vulcanization mold, a vulcanization furnace, a thermometer, a weighing instrument, and a stirrer.

4. The method of modifying butyl rubber using maleic anhydride according to claim 1, characterized in that: The raw material weighing includes weighing each material according to the material ratio, using an electronic scale to weigh the materials, and recording the weight of each raw material. The pretreatment includes heating the mixer to 70-80° C., preheating for 15 minutes, and ensuring temperature stability.

5. The method of modifying butyl rubber using maleic anhydride according to claim 1, characterized in that: The initial mixing includes putting butyl rubber into a mixer, adding hydrogenated nitrile rubber and carbon black, stirring at a low speed for 5 minutes, increasing the speed after the mixture is evenly mixed, and continuing to mix for 5 minutes to ensure even dispersion.

6. The method of modifying butyl rubber using maleic anhydride according to claim 1, characterized in that: The adding of maleic anhydride includes slowly adding maleic anhydride, and the maleic anhydride may be heated to about 50°C to reduce viscosity. The mixing is continued for 10-15 minutes to ensure uniform dispersion, and the speed is adjusted if necessary to optimize the dispersion effect. The adding of the crosslinking agent and the accelerator includes adding sulfur and the accelerator, and continuing to mix at a medium speed for about 5 minutes to ensure uniform distribution of the crosslinking agent and the accelerator. The adding of the antioxidant includes adding the antioxidant, and mixing at a low speed for 3-5 minutes to ensure complete mixing to avoid degradation of the antioxidant caused by high temperature.

7. The method of modifying butyl rubber using maleic anhydride according to claim 1, characterized in that: The vulcanization preparation takes out the mixed rubber and quickly transfers it to the vulcanization mold. A scraper or spatula can be used to help fill the mold. The vulcanization process includes placing the mold in a vulcanization furnace, setting the temperature to 150°C and the vulcanization time to 20 minutes, ensuring that the temperature in the furnace is evenly distributed. If necessary, the temperature can be checked regularly.

8. The method of modifying butyl rubber using maleic anhydride according to claim 1, characterized in that: The cooling and demoulding include taking out the mold from the vulcanizing furnace and cooling it naturally to room temperature to avoid deformation of the product due to rapid cooling. The mold must be demoulded carefully. If there is adhesion, use appropriate tools to pry it gently.

9. The method of modifying butyl rubber using maleic anhydride according to claim 1, characterized in that: The physical property tests include hardness test, tensile strength test, tear strength test, and aging resistance test. The hardness test needs to use a Shore A hardness tester to record the hardness value. The tensile strength test needs to use a tensile testing machine to record the breaking strength and elongation. The tear strength test needs to record the tear strength value. The aging resistance test needs to be carried out in a high temperature and high humidity environment and accelerated aging test.

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