Preparation of high molecular damping agent and high damping bromobutyl rubber

Abstract

The application discloses a high-molecular damping agent and a preparation method thereof, and the high-molecular damping agent is a linear block copolymer composed of p-alkyl styrene and isobutene. The application further discloses a method for preparing high-damping brominated butyl rubber. The method for preparing the high-damping brominated butyl rubber is green and environment-friendly, the processing method is simple, raw materials are easily available on the market, and the method is suitable for industrial production and the like.

Description

Technical Field

[0001] This invention relates to a polymeric damping agent and the preparation of high-damping brominated butyl rubber. Background Technology

[0002] With the rapid development of modern science and technology, mechanical equipment is trending towards high frequency and high speed. While bringing convenience to daily production and life, this has also generated a series of problems, such as high-frequency vibration and noise. These problems not only accelerate the fatigue damage of mechanical structural materials and shorten their service life, but also affect people's daily lives to a certain extent. Therefore, developing high-performance, high-efficiency damping materials and improving their damping and vibration reduction applications is crucial for improving the operating environment of machinery. Due to the unique viscoelasticity of polymers, rubber damping materials have significant damping effects in vibration reduction, noise reduction, and improving the human-machine working environment. They have been widely used in many fields such as high-speed rail, aerospace, naval vessels, mechanical engineering, automobiles, and electronics. In particular, the data storage systems in various IT equipment such as servers, computers, workstations, and switches are subject to vibration and noise from the fan rotation, which seriously affects the service life of hard drives. The demand for high-efficiency damping and vibration reduction products is very urgent. Furthermore, as electronic equipment faces increasingly complex operating environments with lower and higher temperatures, extremely high requirements are placed on rubber damping materials.

[0003] Brominated butyl rubber (BIIR) is produced by introducing bromine atoms into the molecular chain of butyl rubber (IIR) through an electrophilic substitution reaction under the influence of molecular bromine. Compared to IIR, BIIR, in addition to possessing the same excellent airtightness, also exhibits better adhesion, faster vulcanization speed, good thermal stability, and corrosion resistance, enabling its use in extreme environments such as strong corrosion or high temperatures. Furthermore, the introduction of bromine atoms increases the polarity of the molecular chain, leading to increased relaxation resistance and greater internal friction, resulting in excellent damping performance. Therefore, it is one of the most widely used basic damping rubbers. However, brominated butyl rubber currently suffers from drawbacks such as insufficient damping value, unstable damping performance, a limited effective damping temperature range, and unsatisfactory mechanical properties. These limitations prevent it from meeting the damping performance requirements of large equipment and precision instruments, thus becoming a bottleneck for the expanded application of brominated butyl rubber materials.

[0004] In the prior art, the preparation methods of polymer damping materials mainly include blending, copolymerization, interpenetrating polymer networks, and adding organic small molecule functional damping agents.

[0005] CN102229724A, CN102775659B, CN105906956B, CN113969031A, CN103113682A, CN103113682A, CN201110165757.2, and the literature by Tao Gang et al. (Polymer Materials Science and Engineering, 2013, 29(11): 114~118) and Liao Mingyi et al. (Journal of Dalian Maritime University, 2008, 34(2): 83~86) have shown that blending, copolymerization, and interpenetrating polymer networks can broaden the effective damping temperature range of rubber and improve its damping performance to a certain extent. However, these methods still have certain limitations, which can lead to a decrease in the mechanical properties of the modified materials, complex processes, difficult practical operation, large addition amounts, high costs, difficulty in removing organic solvents, and environmental pollution. Summary of the Invention

[0006] One of the objectives of this invention is to provide a maximum damping factor tanδ max A method for preparing high-damping brominated butyl rubber with a strength ≥1.9. This invention first synthesizes a polymeric damping agent by cationic polymerization of p-alkylstyrene and isobutylene in a protic acid-catalyzed system; then, the polymeric damping agent and brominated butyl rubber are compounded and milled to prepare the high-damping brominated butyl rubber. This method significantly improves the compatibility between the polymeric damping agent and brominated butyl rubber, solves the dispersion problem of the polymeric damping agent in the brominated butyl rubber matrix, and not only greatly improves the damping performance of brominated butyl rubber but also increases its tensile strength, endowing it with high efficiency and stability in damping performance, thus meeting the damping performance requirements of automotive shock absorbers, engine shock absorbers, and automotive exhaust suspensions.

[0007] In this invention, "%" refers to mass percentage.

[0008] As one aspect of the present invention, a polymeric damping agent is disclosed, which is a linear block copolymer composed of p-alkylstyrene and isobutylene, having the general structural formula shown in Formula I:

[0009]

[0010] Wherein: R is a C1-C4 alkyl group; n is the number of repeating units: n≥1. The number average molecular weight (Mn) of the polymer damping agent is 60,000-70,000, and the molecular weight distribution (Mw / Mn) is 1.51-2.32.

[0011] As another aspect of the present invention, a method for preparing the above-mentioned polymeric damping agent is provided, comprising: adding 100% to 200% of a mixed solvent (diluent / solvent V:V ratio of 60 to 40 / 40 to 60), 70% to 80% of p-alkylstyrene, and 20% to 30% of isobutylene sequentially to a polymerization reactor, based on 100% of the total mass of the reactants, stirring and mixing until the polymerization system temperature drops to -50 to -60°C; then adding 5% to 10% of the diluent and 0.01% to 0.1% of the co-initiator to the polymerization system at -60 to -70°C for 30 to 40 minutes, stirring and reacting for 1.0 to 2.0 hours; finally adding 1% to 3% of the terminator; discharging, coagulating, washing, and drying to obtain the polymeric damping agent. Preferably, the polymerization reactor is purged with argon gas 3 to 5 times before adding the reactants to the polymerization reactor.

[0012] As another aspect of the present invention, a method for preparing high-damping brominated butyl rubber is provided, comprising:

[0013] Based on 100% of the mass of brominated butyl rubber, first heat the internal mixer to 50-140°C, then add 100% brominated butyl rubber, 10%-20% high molecular weight damping agent, and 0.1%-0.4% stabilizer sequentially to the internal mixer and mix for 30-50 minutes to obtain the masterbatch. After removing the masterbatch and cooling it to room temperature, place it on a two-roll mill and add 8%-20% vulcanizing aid and 5%-15% vulcanizing agent, and mix for 30-40 minutes to prepare the compound. After letting the above compound stand at room temperature for 10-16 hours, place it on a flat vulcanizing machine for vulcanization at a temperature of 120-180°C and a pressure of 8-16 MPa for 15-40 minutes to obtain high-damping brominated butyl rubber.

[0014] The p-alkylstyrene described in this invention is one of p-methylstyrene, p-ethylstyrene, p-propylstyrene, p-n-butylstyrene, p-isobutylstyrene, and p-isopentylstyrene, with p-methylstyrene being preferred.

[0015] The brominated butyl rubber (BIIR) described in this invention is a polymer obtained by bromine atom substitution of a copolymer of isobutylene and isoprene. The Mooney viscosity ML(1+4) at 100°C is 30-60, and the bromine content is 1wt%-5wt%.

[0016] The diluent described in this invention is a haloalkane, wherein the halogen atom in the haloalkane can be chlorine, bromine, or fluorine; and the number of carbon atoms in the haloalkane is C1-C4. This haloalkane is selected from one of chloromethane, dichloromethane, carbon tetrachloride, dichloroethane, tetrachloropropane, heptachloropropane, fluoromethane, difluoromethane, tetrafluoroethane, carbon hexafluoride, and fluorobutane, preferably chloromethane.

[0017] The co-initiator of this invention is composed of alkyl aluminum halides and protic acids in different proportions. The alkyl aluminum halide is selected from at least one of diethylaluminum chloride, diisobutylaluminum chloride, dichloromethylaluminum, sesquiethylaluminum chloride, sesquiisobutylaluminum chloride, dichloro-n-propylaluminum, dichloroisopropylaluminum, dimethylaluminum chloride, and ethylaluminum chloride, preferably sesquiethylaluminum chloride. The protic acid is selected from one of HCl, HF, HBr, H2SO4, H2CO3, H3PO4, and HNO3, preferably HCl. The total amount of co-initiator added is 0.01% to 0.5%, and the molar ratio of protic acid to alkyl aluminum halide is 0.01:1 to 0.1:1.

[0018] The polymerization reactions described in this invention are all carried out in an oxygen-free and anhydrous environment, preferably in an inert gas environment. The polymerization process is completed in a hydrocarbon solvent, which is a hydrocarbon solvent including straight-chain alkanes, aromatics and cycloalkanes. This hydrocarbon solvent is selected from one of pentane, hexane, octane, heptane, cyclohexane, benzene, toluene, xylene and ethylbenzene, with hexane being preferred.

[0019] The terminating agent described in this invention may be selected from one or more of methanol, ethanol, and butanol.

[0020] In the preparation process of the high-damping brominated butyl rubber described in this invention, stabilizers, vulcanizing auxiliaries, and vulcanizing agents are required. These auxiliaries are not particularly limited to meet the requirements for stable processing of the rubber material; all can be conventional auxiliaries commonly used in the field. For example, the stabilizer is a stearate, such as zinc stearate, magnesium stearate, or calcium stearate, preferably zinc stearate. The vulcanizing agent is a phenolic resin, such as phenol-formaldehyde resin, alkylphenol-formaldehyde resin, tert-butylphenol-formaldehyde resin, or tert-octylphenol-formaldehyde resin, preferably phenol-formaldehyde resin. The vulcanizing auxiliaries are selected from zinc diacrylate (ZDA), zinc methacrylate, zinc dimethacrylate (ZDMA), trimethylolpropane triacrylate (TMPTA), and zinc oxide (ZnO), preferably ZnO.

[0021] The polymeric damping agent prepared in this invention combines p-methylphenyl and methyl groups on a single macromolecular chain through cationic polymerization. The regular arrangement of the molecular chain results in a significant "synergistic effect" in improving the damping properties of brominated butyl rubber due to the high rigidity and steric hindrance of the p-methylphenyl group, the regular arrangement of the side methyl groups on the main chain, and the narrow molecular weight distribution.

[0022] Both the polymeric damping agent and brominated butyl rubber contain isobutylene unit chain structures in their main chains, which can significantly improve the compatibility between the polymeric damping agent and brominated butyl rubber. This effectively solves the problem of uneven precipitation and dispersion of the polymeric damping agent in the brominated butyl rubber matrix, thus significantly enhancing the "synergistic effect" of the polymeric damping agent in improving the damping performance of brominated butyl rubber. This greatly improves the damping performance of brominated butyl rubber and allows for the preparation of the maximum damping factor tanδ. max High-damping brominated butyl rubber with a resistance of ≥1.9.

[0023] The polymeric damping agent prepared by this invention utilizes the combined effects of "group factors", "structural factors" and "narrow molecular weight distribution" to improve the damping properties of brominated butyl rubber. This not only avoids the problem of decreased mechanical properties and air tightness of brominated butyl rubber, but also improves the tensile strength of butyl rubber, thus meeting the damping performance requirements of automotive shock absorbers, engine shock absorbers and automotive exhaust suspensions.

[0024] The method for preparing high-damping brominated butyl rubber of this invention is green and environmentally friendly, with simple processing methods, readily available raw materials, and suitable for industrial production. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be clearly and completely described below in conjunction with the embodiments of this invention. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0026] (1) Source of raw materials:

[0027] Brominated Butyl Rubber (BIIR2302) Zhejiang Xinhui New Material Co., Ltd.

[0028] Isobutylene Polymer Grade Zhejiang Xinhui New Material Co., Ltd.

[0029] p-Methylstyrene, Polymer Grade, Jiande Langfeng Chemical Co., Ltd.

[0030] p-Ethylstyrene, Polymer Grade, Jiande Langfeng Chemical Co., Ltd.

[0031] For n-butylstyrene, polymer-grade Luoyang Boyu Energy Technology Co., Ltd.

[0032] Sesquiethylaluminum chloride, 98% purity. Bailingwei Technology Co., Ltd.

[0033] Phenol-Formaldehyde Resin Shenzhen Yoshida Chemical Co., Ltd.

[0034] All other reagents are commercially available industrial products.

[0035] (2) Analysis and testing methods:

[0036] Molecular weight and its distribution were determined using a Waters 2414 gel permeation chromatography (GPC) system (USA). A polystyrene standard was used as the calibration curve. The mobile phase was tetrahydrofuran, the column temperature was 40℃, the sample concentration was 1 mg / mL, the injection volume was 50 µL, the elution time was 40 min, and the flow rate was 1 mL / min. -1 .

[0037] Dynamic mechanical analysis (DMA): Measurements were performed in tensile mode on a Netzsch 242C dynamic mechanical analyzer (Germany). Sample dimensions were 10 mm long, 6 mm wide, and 2 mm thick. The temperature range was -90℃ to 90℃, with a heating rate of 3℃ / min. Data were analyzed at a frequency of 10 Hz.

[0038] Air tightness determination: An automated air tightness tester was used to determine the air permeability number according to ISO 2782-1:2022. The test gas was N2, the test temperature was 23℃, and the test sample was an 8cm diameter circular sea sheet with a thickness of 1mm.

[0039] Tensile strength: The method specified in standard GB / T528-2009 shall be applied.

[0040] Example 1

[0041] (1) Preparation of polymeric damping agent: First, in a 10L stainless steel reactor with a jacket, argon gas was purged three times. Then, 600g of chloromethane, 400g of pentane, 700g of p-methylstyrene, and 300g of isobutylene were added to the polymerization reactor. The mixture was stirred until the polymerization system temperature dropped to -50℃. Then, 50g of chloromethane, 0.158g of sesquiethylaluminum chloride, and 0.005g of HCl were mixed and aged at -60℃ for 30 minutes. These were then added to the polymerization system and stirred for 1.0hr. Finally, 10g of ethanol was added, and the mixture was discharged, coagulated, washed, and dried to obtain the polymeric damping agent (Mn = 60400, Mw / Mn = 1.51). Please supplement the structural formula information of the polymeric damping agent in each example. In the polymeric damping agent obtained in this example, in the general formula described in Formula I, R is methyl (CH3); n is the number of repeating units: n≥1.

[0042] (2) Preparation of high-damping brominated butyl rubber: First, heat the internal mixer to 50°C, then add 1000g BIIR2302, 100g polymeric damping agent, and 1.0g zinc stearate sequentially to the internal mixer and mix for 30 min to obtain the masterbatch; after cooling the masterbatch to room temperature, place it on a two-roll mill and add 80g ZnO and 50g phenol-formaldehyde resin, mix for 30 min to obtain the compound; after letting the above compound stand at room temperature for 10 hours, place it on a flat vulcanizing machine for vulcanization, heat to 120°C, pressure 8MPa, and vulcanize for 15 min to prepare the high-damping brominated butyl rubber. Sampling and analysis: Standard samples were prepared, and the test performance is shown in Table 1.

[0043] Example 2

[0044] (1) Preparation of polymeric damping agent: First, in a 10L stainless steel reactor with a jacket, argon gas was purged three times. Then, 500g of chloromethane, 500g of pentane, 710g of p-methylstyrene, and 290g of isobutylene were added to the polymerization reactor. The mixture was stirred until the temperature of the polymerization system dropped to -51℃. Then, 60g of chloromethane, 0.223g of sesquiethylaluminum chloride, and 0.007g of HCl were mixed and aged at -62℃ for 31min. The mixture was then added to the polymerization system and stirred for 1.1hr. Finally, 13g of ethanol was added, and the mixture was discharged, coagulated, washed, and dried to obtain the polymeric damping agent (Mn = 61200, Mw / Mn = 1.65). In the polymeric damping agent obtained in this example, in the general formula described in Formula I, R is methyl (CH3); n is the number of repeating units: n≥1.

[0045] (2) Preparation of high-damping brominated butyl rubber: First, when the internal mixer is heated to 50°C, 1000g of BIIR2302, 110g of polymeric damping agent, and 1.5g of zinc stearate are added sequentially to the internal mixer and mixed for 35 min to obtain the masterbatch. After the masterbatch is removed and cooled to room temperature, it is placed on a two-roll mill and 100g of ZnO and 70g of phenol-formaldehyde resin are added and mixed for 31 min to obtain the compound. After the above compound is allowed to stand at room temperature for 11 hours, it is placed on a flat vulcanizing machine for vulcanization. The temperature is raised to 130°C and the pressure is 9MPa. Vulcanization is carried out for 17 min to prepare high-damping brominated butyl rubber. Sampling and analysis: Standard samples were prepared, and the test performance is shown in Table 1.

[0046] Example 3

[0047] (1) Preparation of polymeric damping agent: First, in a 10L stainless steel reactor with a jacket, argon gas was purged three times. Then, 400g of chloromethane, 600g of pentane, 720g of p-methylstyrene, and 280g of isobutylene were added to the polymerization reactor. The mixture was stirred until the temperature of the polymerization system dropped to -52℃. Then, 70g of chloromethane, 0.316g of sesquiethylaluminum chloride, and 0.009g of HCl were mixed and aged at -63℃ for 32min. The mixture was then added to the polymerization system and stirred for 1.2hr. Finally, 15g of ethanol was added, and the mixture was discharged, coagulated, washed, and dried to obtain the polymeric damping agent (Mn = 62800, Mw / Mn = 1.73). In the polymeric damping agent obtained in this example, in the general formula described in Formula I, R is methyl (CH3); n is the number of repeating units: n≥1.

[0048] (2) Preparation of high-damping brominated butyl rubber: First, when the internal mixer is heated to 60°C, 1000g of BIIR2302, 130g of polymeric damping agent, and 2.0g of zinc stearate are added sequentially to the internal mixer and mixed for 38 min to obtain the masterbatch. After the masterbatch is removed and cooled to room temperature, it is placed on a two-roll mill and 110g of ZnO and 80g of phenol-formaldehyde resin are added and mixed for 33 min to obtain the compound. After the above compound is allowed to stand at room temperature for 12 hours, it is placed on a flat vulcanizing machine for vulcanization. The temperature is raised to 140°C and the pressure is 10MPa. Vulcanization is carried out for 20 min to prepare high-damping brominated butyl rubber. Sampling and analysis: Standard samples were prepared, and the test performance is shown in Table 1.

[0049] Example 4

[0050] (1) Preparation of polymeric damping agent: First, in a 10L stainless steel reactor with a jacket, argon gas was purged four times. Then, 900g of chloromethane, 600g of pentane, 740g of p-methylstyrene, and 260g of isobutylene were added to the polymerization reactor. The mixture was stirred until the temperature of the polymerization system dropped to -53℃. Then, 80g of chloromethane, 0.425g of sesquiethylaluminum chloride, and 0.011g of HCl were mixed and aged at -64℃ for 33min. The mixture was then added to the polymerization system and stirred for 1.4hr. Finally, 18g of ethanol was added, and the mixture was discharged, coagulated, washed, and dried to obtain the polymeric damping agent (Mn = 64100, Mw / Mn = 1.85). In the polymeric damping agent obtained in this example, in the general formula described in Formula I, R is methyl (CH3); n is the number of repeating units: n≥1.

[0051] (2) Preparation of high-damping brominated butyl rubber: First, when the internal mixer is heated to 80°C, 1000g of BIIR2302, 140g of polymeric damping agent, and 2.6g of zinc stearate are added sequentially to the internal mixer and mixed for 40 min to obtain the masterbatch. After the masterbatch is removed and cooled to room temperature, it is placed on a two-roll mill and 130g of ZnO and 90g of phenol-formaldehyde resin are added and mixed for 34 min to obtain the compound. After the above compound is allowed to stand at room temperature for 12 hours, it is placed on a flat vulcanizing machine for vulcanization. The temperature is raised to 150°C and the pressure is 11MPa. Vulcanization is carried out for 22 min to prepare high-damping brominated butyl rubber. Sampling and analysis: Standard samples were prepared, and the test performance is shown in Table 1.

[0052] Example 5

[0053] (1) Preparation of polymeric damping agent: First, in a 10L stainless steel reactor with a jacket, argon gas was purged four times. 700g of chloromethane, 800g of pentane, 760g of p-methylstyrene, and 240g of isobutylene were added to the polymerization reactor. The mixture was stirred until the temperature of the polymerization system dropped to -55℃. Then, 85g of chloromethane, 0.568g of sesquiethylaluminum chloride, and 0.018g of HCl were mixed and aged at -65℃ for 35min. After that, they were added to the polymerization system and stirred for 1.6hr. Finally, 20g of ethanol was added. The mixture was discharged, coagulated, washed, and dried to obtain the polymeric damping agent (Mn is 65700, Mw / Mn is 1.97). In the polymeric damping agent obtained in this example, R is methyl (CH3) in the general formula I; n is the number of repeating units: n≥1.

[0054] (2) Preparation of high-damping brominated butyl rubber: First, when the internal mixer is heated to 100°C, 1000g of BIIR2302, 160g of polymeric damping agent, and 3.0g of zinc stearate are added sequentially to the internal mixer and mixed for 42 min to obtain the masterbatch. After the masterbatch is removed and cooled to room temperature, it is placed on a two-roll mill and 150g of ZnO and 110g of phenol-formaldehyde resin are added and mixed for 35 min to obtain the compound. After the above compound is allowed to stand at room temperature for 13 hours, it is placed on a flat vulcanizing machine for vulcanization. The temperature is raised to 160°C and the pressure is 12MPa. Vulcanization is carried out for 26 min to prepare high-damping brominated butyl rubber. Sampling and analysis: Standard samples were prepared, and the test performance is shown in Table 1.

[0055] Example 6

[0056] (1) Preparation of polymeric damping agent: First, in a 10L stainless steel reactor with a jacket, argon gas was purged four times. Then, 600g of chloromethane, 900g of pentane, 770g of p-ethylstyrene, and 230g of isobutylene were added to the polymerization reactor. The mixture was stirred until the polymerization system temperature dropped to -56℃. Next, 90g of chloromethane, 0.631g of sesquiethylaluminum chloride, and 0.026g of HCl were mixed and aged at -67℃ for 36 minutes. These were then added to the polymerization system and stirred for 1.7 hours. Finally, 22g of ethanol was added, and the mixture was discharged, coagulated, washed, and dried to obtain the polymeric damping agent (Mn = 67300, Mw / Mn = 2.15). In the polymeric damping agent obtained in this example, in the general formula described in Formula I, R is ethyl (C2H5); n is the number of repeating units: n≥1.

[0057] (2) Preparation of high-damping brominated butyl rubber: First, when the internal mixer is heated to 110°C, 1000g of BIIR2302, 170g of polymeric damping agent, and 3.3g of zinc stearate are added sequentially to the internal mixer and mixed for 45 min to obtain the masterbatch. After the masterbatch is removed and cooled to room temperature, it is placed on a two-roll mill and 160g of ZnO and 120g of phenol-formaldehyde resin are added and mixed for 36 min to obtain the compound. After the above compound is allowed to stand at room temperature for 14 hours, it is placed on a flat vulcanizing machine for vulcanization. The temperature is raised to 170°C and the pressure is 13MPa. Vulcanization is carried out for 30 min to prepare high-damping brominated butyl rubber. Sampling and analysis: Standard samples were prepared, and the test performance is shown in Table 1.

[0058] Example 7

[0059] (1) Preparation of polymeric damping agent: First, in a 10L stainless steel reactor with a jacket, argon gas was purged five times. Then, 1200g of chloromethane, 800g of pentane, 780g of p-methylstyrene, and 220g of isobutylene were added to the polymerization reactor and stirred until the polymerization system temperature dropped to -58℃. Then, 95g of chloromethane, 0.711g of sesquiethylaluminum chloride, and 0.035g of HCl were mixed and aged at -68℃ for 38min. After that, they were added to the polymerization system and stirred for 1.8hr. Finally, 25g of ethanol was added, and the mixture was discharged, coagulated, washed, and dried to obtain the polymeric damping agent (Mn is 68600, Mw / Mn is 2.23). In the polymeric damping agent obtained in this example, in the general formula described in Formula I, R is methyl (CH3); n is the number of repeating units: n≥1.

[0060] (2) Preparation of high-damping brominated butyl rubber: First, when the internal mixer is heated to 120°C, 1000g of BIIR2302, 180g of polymeric damping agent, and 3.7g of zinc stearate are added sequentially to the internal mixer and mixed for 47 min to obtain the masterbatch. After the masterbatch is removed and cooled to room temperature, it is placed on a two-roll mill and 180g of ZnO and 130g of phenol-formaldehyde resin are added and mixed for 39 min to obtain the compound. After the above compound is allowed to stand at room temperature for 15 hours, it is placed on a flat vulcanizing machine for vulcanization. The temperature is raised to 175°C and the pressure is 14MPa. Vulcanization is carried out for 35 min to prepare high-damping brominated butyl rubber. Sampling and analysis: Standard samples were prepared, and the test performance is shown in Table 1.

[0061] Example 8

[0062] (1) Preparation of polymeric damping agent: First, in a 10L stainless steel reactor with a jacket, argon gas was purged 5 times. Then, 800g of chloromethane, 1200g of pentane, 800g of p-n-butylstyrene, and 200g of isobutylene were added to the polymerization reactor. The mixture was stirred until the temperature of the polymerization system dropped to -60℃. Then, 100g of chloromethane, 0.891g of sesquiethylaluminum chloride, and 0.047g of HCl were mixed and aged at -70℃ for 40min. The mixture was then added to the polymerization system and stirred for 2.0hr. Finally, 30g of ethanol was added, and the mixture was discharged, coagulated, washed, and dried to obtain the polymeric damping agent (Mn is 69700, Mw / Mn is 2.32). In the polymeric damping agent obtained in this example, in the general formula described in Formula I, R is butyl (C4H9); n is the number of repeating units: n≥1.

[0063] (2) Preparation of high-damping brominated butyl rubber: First, when the internal mixer is heated to 140°C, 1000g of BIIR2302, 200g of polymeric damping agent, and 4.0g of zinc stearate are added sequentially to the internal mixer and mixed for 50 min to obtain the masterbatch. After the masterbatch is removed and cooled to room temperature, 200g of ZnO and 150g of phenol-formaldehyde resin are added to a two-roll mill and mixed for 40 min to obtain the compound. After the above compound is allowed to stand at room temperature for 16 hours, it is placed on a flat vulcanizing machine for vulcanization. The temperature is raised to 180°C and the pressure is 16MPa. Vulcanization is carried out for 40 min to prepare high-damping brominated butyl rubber. Sampling and analysis: Standard samples were prepared, and the test performance is shown in Table 1.

[0064] Comparative Example 1

[0065] (1) Preparation of polymeric damping agent: Other conditions are the same as in Example 1, except that: p-methylstyrene is not added in the preparation of polymeric damping agent, but styrene is added, and the amount added is 700g. That is: first, in a 10L stainless steel reactor with a jacket, argon gas is passed through three times to replace the reactor. 600g of chloromethane, 400g of pentane, 700g of styrene and 300g of isobutylene are added to the polymerization reactor and stirred until the temperature of the polymerization system drops to -50℃. Then, 50g of chloromethane, 0.158g of sesquiethylaluminum chloride and 0.005g of HCl are mixed and aged at -60℃ for 30min. After that, they are added to the polymerization system and stirred for 1.0hr. Finally, 10g of ethanol is added, the material is discharged, coagulated, washed and dried to obtain polymeric damping agent-1 (Mn is 60100, Mw / Mn is 1.49). In the polymeric damping agent obtained in this comparative example, in the general formula described in Formula I, R is hydrogen (H); n is the number of repeating units: n≥1.

[0066] (2) Preparation of high-damping brominated butyl rubber: Other conditions are the same as in Example 1, except that no polymeric damping agent is added during the preparation of high-damping brominated butyl rubber. Instead, polymeric damping agent-1 is added in an amount of 100g. That is, when the internal mixer is heated to 50°C, 1000g of BIIR2302, 100g of polymeric damping agent-1 and 1.0g of zinc stearate are added to the internal mixer in sequence and mixed for 30 min to obtain the masterbatch. After the masterbatch is cooled to room temperature, it is placed on a two-roll mill and 80g of ZnO and 50g of phenol-formaldehyde resin are added and mixed for 30 min to obtain the compound. After the above compound is left to stand at room temperature for 10 hours, it is placed on a flat vulcanizing machine for vulcanization. The temperature is raised to 120°C and the pressure is 8MPa. The vulcanization is carried out for 15 min to prepare high-damping brominated butyl rubber. Sampling and analysis: Standard samples were prepared and the test performance is shown in Table 1.

[0067] Comparative Example 2

[0068] (1) Preparation of polymeric damping agent: Other conditions are the same as in Example 2. The difference is that the amount of p-methylstyrene added in the preparation of polymeric damping agent is 600g. That is: First, in a 10L stainless steel reactor with a jacket, argon gas is passed through three times for purging. Then, 500g of chloromethane, 500g of pentane, 600g of p-methylstyrene, and 290g of isobutylene are added to the polymerization reactor. The mixture is stirred until the temperature of the polymerization system drops to -51℃. Then, 60g of chloromethane, 0.223g of sesquiethylaluminum chloride, and 0.007g of HCl are mixed and aged at -62℃ for 31min. Then, they are added to the polymerization system and stirred for 1.1hr. Finally, 13g of ethanol is added. The mixture is discharged, coagulated, washed, and dried to obtain polymeric damping agent-2 (Mn is 52900, Mw / Mn is 1.61). The polymeric damping agent obtained in this comparative example, in the general formula described in Formula I, R is methyl (CH3); n is the number of repeating units: n≥1.

[0069] (2) Preparation of high-damping brominated butyl rubber: Other conditions are the same as in Example 2, except that no polymeric damping agent is added during the preparation of high-damping brominated butyl rubber. Instead, polymeric damping agent-2 is added in an amount of 110g. Specifically, when the internal mixer is heated to 50°C, 1000g of BIIR2302, 110g of polymeric damping agent-2, and 1.5g of zinc stearate are added sequentially to the internal mixer and mixed for 35 min to obtain the masterbatch. After the masterbatch is cooled to room temperature, it is placed on a two-roll mill and 100g of ZnO and 70g of phenol-formaldehyde resin are added and mixed for 31 min to obtain the compound. After the compound is left to stand at room temperature for 11 hours, it is placed on a flat vulcanizing machine for vulcanization. The temperature is raised to 130°C and the pressure is 9MPa. The vulcanization time is 17 min to prepare high-damping brominated butyl rubber. Sampling and analysis: Standard samples were prepared, and the test performance is shown in Table 1.

[0070] Comparative Example 3

[0071] (1) Preparation of polymeric damping agent: Other conditions are the same as in Example 3, except that: free radical polymerization is used in the preparation of polymeric damping agent, and benzoic acid peroxide (BPO) is added instead of sesquiethyl aluminum chloride as the initiator. The amount added is 0.316 g. That is: first, argon gas is purged three times in a 10L stainless steel reactor with a jacket, and 400 g of chloromethane, 600 g of pentane, 720 g of p-methylstyrene and 280 g of isobutylene are added to the polymerization reactor. The mixture is stirred until the temperature of the polymerization system drops to -52℃. Then, 70 g of chloromethane, 0.316 g of BPO and 0.009 g of HCl are mixed and aged at -63℃ for 32 min. Then, they are added to the polymerization system and stirred for 1.2 hours. Finally, 15 g of ethanol is added, the mixture is discharged, coagulated, washed and dried to obtain polymeric damping agent-3 (Mn is 31000, Mw / Mn is 5.56). The polymeric damping agent obtained in this comparative example, in the general formula described in Formula I, R is methyl (CH3); n is the number of repeating units: n≥1.

[0072] (2) Preparation of high-damping brominated butyl rubber: Other conditions are the same as in Example 3, except that: no polymer damping agent is added during the preparation of high-damping brominated butyl rubber, but polymer damping agent-3 is added, and the amount added is 130g. That is: first, when the internal mixer is heated to 60°C, 1000g of BIIR2302, 130g of polymer damping agent-3 and 2.0g of zinc stearate are added to the internal mixer in sequence, and the mixture is mixed for 38 min to obtain the masterbatch; after the masterbatch is taken out and cooled at room temperature, it is placed on a two-roll open mill and 110g of ZnO and 80g of phenol-formaldehyde resin are added, and the mixture is mixed for 33 min to obtain the compound; after the above compound is left to stand at room temperature for 12 hours, it is placed on a flat vulcanizing machine for vulcanization, heated to 140°C, pressure of 10MPa, and vulcanized for 20 min to prepare high-damping brominated butyl rubber. Sampling and analysis: Standard samples were prepared, and the test performance is shown in Table 1.

[0073] Comparative Example 4

[0074] (1) Preparation of polymer damping agent: Other conditions are the same as in Example 4. The difference is that the amount of isobutylene added in the preparation of polymer damping agent is 100g. That is: First, in a 10L stainless steel reactor with a jacket, argon gas is passed through 4 times for replacement. Then, 900g of chloromethane, 600g of pentane, 740g of p-methylstyrene and 100g of isobutylene are added to the polymerization reactor. The mixture is stirred until the temperature of the polymerization system drops to -53℃. Then, 80g of chloromethane, 0.425g of sesquiethylaluminum chloride and 0.011g of HCl are mixed and aged at -64℃ for 33min. Then, they are added to the polymerization system and stirred for 1.4hr. Finally, 18g of ethanol is added. The mixture is discharged, coagulated, washed and dried to obtain polymer damping agent-4 (Mn is 58700, Mw / Mn is 1.89). The polymeric damping agent obtained in this comparative example, in the general formula described in Formula I, R is methyl (CH3); n is the number of repeating units: n≥1.

[0075] (2) Preparation of high-damping brominated butyl rubber: Other conditions are the same as in Example 4, except that: no polymer damping agent is added during the preparation of high-damping brominated butyl rubber, but polymer damping agent-4 is added, and the amount added is 140g. That is: first, when the internal mixer is heated to 80°C, 1000g of BIIR2302, 140g of polymer damping agent-4 and 2.6g of zinc stearate are added to the internal mixer in sequence, and the mixture is mixed for 40 min to obtain the masterbatch; after the masterbatch is taken out and cooled at room temperature, it is placed on a two-roll open mill and 130g of ZnO and 90g of phenol-formaldehyde resin are added, and the mixture is mixed for 34 min to obtain the compound; after the above compound is left to stand at room temperature for 12 hours, it is placed on a flat vulcanizing machine for vulcanization, heated to 150°C, pressure of 11MPa, and vulcanized for 22 min to prepare high-damping brominated butyl rubber. Sampling and analysis: Standard samples were prepared, and the test performance is shown in Table 1.

[0076] Comparative Example 5

[0077] (1) Preparation of polymeric damping agent: Other conditions are the same as in Example 5, except that isobutylene is not added during the preparation of polymeric damping agent. That is: First, in a 10L stainless steel reactor with a jacket, argon gas is purged four times. Then, 700g of chloromethane, 800g of pentane, and 760g of p-methylstyrene are added to the polymerization reactor and stirred until the temperature of the polymerization system drops to -55℃. Then, 85g of chloromethane, 0.568g of sesquiethylaluminum chloride, and 0.018g of HCl are mixed and aged at -65℃ for 35min. After that, they are added to the polymerization system and stirred for 1.6hr. Finally, 20g of ethanol is added, and the mixture is discharged, coagulated, washed, and dried to obtain polymeric damping agent-5 (Mn is 51200, Mw / Mn is 1.85). In the polymeric damping agent obtained in this comparative example, R is methyl (CH3) in the general formula I; n is the number of repeating units: n≥1.

[0078] (2) Preparation of high-damping brominated butyl rubber: Other conditions are the same as in Example 5, except that: no polymer damping agent is added during the preparation of high-damping brominated butyl rubber, but polymer damping agent-5 is added, and the amount added is 160g. That is: first, when the internal mixer is heated to 100°C, 1000g of BIIR2302, 160g of polymer damping agent-5 and 3.0g of zinc stearate are added to the internal mixer in sequence, and the mixture is mixed for 42 min to obtain the masterbatch; after the masterbatch is taken out and cooled at room temperature, it is placed on a two-roll open mill and 150g of ZnO and 110g of phenol-formaldehyde resin are added, and the mixture is mixed for 35 min to obtain the compound; after the above compound is left to stand at room temperature for 13 hours, it is placed on a flat vulcanizing machine for vulcanization, heated to 160°C, pressure of 12MPa, and vulcanized for 26 min to prepare high-damping brominated butyl rubber. Sampling and analysis: Standard samples were prepared, and the test performance is shown in Table 1.

[0079] Comparative Example 6

[0080] (1) Preparation of polymeric damping agent: Other conditions are the same as in Example 6, except that the polymerization system temperature is lowered to -35°C during the preparation of polymeric damping agent. Specifically, firstly, argon gas is purged four times in a 10L stainless steel reactor with a jacket. Then, 600g of chloromethane, 900g of pentane, 770g of p-ethylstyrene, and 230g of isobutylene are added to the polymerization reactor and stirred until the polymerization system temperature drops to -35°C. Then, 90g of chloromethane, 0.631g of sesquiethylaluminum chloride, and 0.026g of HCl are mixed and aged at -67°C for 36 minutes. After that, they are added to the polymerization system and stirred for 1.7 hours. Finally, 22g of ethanol is added, and the mixture is discharged, coagulated, washed, and dried to obtain polymeric damping agent-6 (Mn is 17300, Mw / Mn is 6.28). The polymeric damping agent obtained in this comparative example, in the general formula described in Formula I, R is ethyl (C2H5); n is the number of repeating units: n≥1.

[0081] (2) Preparation of high-damping brominated butyl rubber: Other conditions are the same as in Example 6, except that: no polymer damping agent is added during the preparation of high-damping brominated butyl rubber, but polymer damping agent-6 is added, and the amount added is 170g. That is: first, when the internal mixer is heated to 110°C, 1000g of BIIR2302, 170g of polymer damping agent-6 and 3.3g of zinc stearate are added to the internal mixer in sequence, and the mixture is mixed for 45 min to obtain the masterbatch; after the masterbatch is taken out and cooled at room temperature, it is placed on a two-roll open mill and 160g of ZnO and 120g of phenol-formaldehyde resin are added, and the mixture is mixed for 36 min to obtain the compound; after the above compound is left to stand at room temperature for 14 hours, it is placed on a flat vulcanizing machine for vulcanization, heated to 170°C, pressure of 13MPa, and vulcanized for 30 min to prepare high-damping brominated butyl rubber. Sampling and analysis: Standard samples were prepared, and the test performance is shown in Table 1.

[0082] Comparative Example 7

[0083] (1) Preparation of polymeric damping agent: Other conditions are the same as in Example 7, except that p-methylstyrene is not added in the preparation of polymeric damping agent. That is: First, in a 10L stainless steel reactor with a jacket, argon gas is purged 5 times. Then, 1200g of chloromethane, 800g of pentane, and 220g of isobutylene are added to the polymerization reactor and stirred until the temperature of the polymerization system drops to -58℃. Then, 95g of chloromethane, 0.711g of sesquiethylaluminum chloride, and 0.035g of HCl are mixed and aged at -68℃ for 38min. Then, they are added to the polymerization system and stirred for 1.8hr. Finally, 25g of ethanol is added, and the mixture is discharged, coagulated, washed, and dried to obtain polymeric damping agent-7 (Mn is 17600, Mw / Mn is 2.06).

[0084] (2) Preparation of high-damping brominated butyl rubber: Other conditions are the same as in Example 7, except that: no polymer damping agent is added during the preparation of high-damping brominated butyl rubber, but polymer damping agent-7 is added, and the amount added is 180g. That is: first, when the internal mixer is heated to 120°C, 1000g of BIIR2302, 180g of polymer damping agent-7 and 3.7g of zinc stearate are added to the internal mixer in sequence, and the mixture is mixed for 47 min to obtain the masterbatch; after the masterbatch is taken out and cooled at room temperature, it is placed on a two-roll open mill and 180g of ZnO and 130g of phenol-formaldehyde resin are added, and the mixture is mixed for 39 min to obtain the compound; after the above compound is left to stand at room temperature for 15 hours, it is placed on a flat vulcanizing machine for vulcanization, heated to 175°C, pressure of 14MPa, and vulcanized for 35 min to prepare high-damping brominated butyl rubber. Sampling and analysis: Standard samples were prepared, and the test performance is shown in Table 1.

[0085] Comparative Example 8

[0086] (1) Preparation of polymer damping agent: Same as in Example 8.

[0087] (2) Preparation of high-damping brominated branched butyl rubber: Other conditions are the same as in Example 8, except that the amount of polymer damping agent added during the preparation of high-damping brominated butyl rubber is 80g. That is: first, when the internal mixer is heated to 140°C, 1000g of BIIR2302, 80g of polymer damping agent and 4.0g of zinc stearate are added to the internal mixer in sequence, and the mixture is mixed for 50min to obtain the masterbatch; after the masterbatch is taken out and cooled to room temperature, it is placed on a two-roll open mill and 200g of ZnO and 150g of phenol-formaldehyde resin are added, and the mixture is mixed for 40min to obtain the compound; after the above compound is left to stand at room temperature for 16 hours, it is placed on a flat vulcanizing machine for vulcanization, heated to 180°C, pressure of 16MPa, and vulcanized for 40min to prepare high-damping brominated butyl rubber. Sampling and analysis: standard samples were prepared, and the test performance is shown in Table 1.

[0088] Table 1 Properties of high-damping brominated butyl rubber

[0089]

Claims

1. A method for preparing high-damping brominated butyl rubber, characterized in that, include: Based on 100% of the total mass of the reactants, 100% to 200% of a mixed solvent (a diluent / solvent mixture of 60% to 40% and 40% to 60%), 70% to 80% p-alkylstyrene, and 20% to 30% isobutylene are added sequentially to the polymerization reactor. The mixture is stirred until the polymerization system temperature drops to -50 to -60°C. Then, 5% to 10% of the diluent and 0.01% to 0.1% of the co-initiator are mixed and aged at -60 to -70°C for 30 to 40 minutes, and then added to the polymerization system. The mixture is stirred and reacted for 1.0 to 2.0 hours. Finally, 1% to 3% of the terminator is added, and the mixture is discharged, coagulated, washed, and dried to obtain a polymeric damping agent. The number average molecular weight of the polymeric damping agent is 60,000 to 70,000, and the molecular weight distribution is 1.51 to 2.

32. The co-initiator is a combination of alkyl aluminum halide and protic acid; Based on 100% of the mass of brominated butyl rubber, heat the internal mixer to 50-140°C, then sequentially add 100% brominated butyl rubber, 10%-20% high molecular weight damping agent, and 0.1%-0.4% stabilizer to the internal mixer and mix for 30-50 minutes to obtain the masterbatch. After removing the masterbatch and cooling it to room temperature, place it on a two-roll mill and add 8%-20% vulcanizing aid and 5%-15% vulcanizing agent, and mix for 30-40 minutes to prepare the compound. After letting the above compound stand at room temperature for 10-16 hours, place it on a flat vulcanizing machine for vulcanization at a temperature of 120-180°C and a pressure of 8-16 MPa for 15-40 minutes to obtain high-damping brominated butyl rubber.

2. The method according to claim 1, characterized in that, The p-alkylstyrene is one of p-methylstyrene, p-ethylstyrene, p-propylstyrene, p-n-butylstyrene, p-isobutylstyrene, and p-isopentylstyrene.

3. The method according to claim 2, characterized in that, The p-alkylstyrene mentioned is methylstyrene.

4. The method according to claim 1, characterized in that, The diluent is a haloalkane, wherein the halogen atom in the haloalkane is chlorine, bromine or fluorine; and the number of carbon atoms in the haloalkane is C1-C4.

5. The method according to claim 4, characterized in that, The haloalkane is selected from one of the following: chloromethane, dichloromethane, carbon tetrachloride, dichloroethane, tetrachloropropane, heptachloropropane, fluoromethane, difluoromethane, tetrafluoroethane, carbon hexafluoride, and fluorobutane.

6. The method according to claim 5, characterized in that, The haloalkane is chloromethane.

7. The method according to claim 1, characterized in that, The alkyl aluminum halide is selected from at least one of diethylaluminum chloride, diisobutylaluminum chloride, dichloromethylaluminum, sesquiethylaluminum chloride, sesquiisobutylaluminum chloride, dichloro-n-propylaluminum, dichloroisopropylaluminum, dimethylaluminum chloride, and ethylaluminum chloride; the protic acid is selected from one of HCl, HF, HBr, H2SO4, H2CO3, H3PO4, and HNO3.

8. The method according to claim 7, characterized in that, The alkyl aluminum halide is sesquiethyl aluminum chloride, and the protic acid is HCl.

9. The method according to claim 1, characterized in that, The molar ratio of protic acid to alkyl aluminum halide is 0.01:1 to 0.1:

1.

10. The method according to claim 1, characterized in that, The solvent is a hydrocarbon solvent, which is selected from one of pentane, hexane, octane, heptane, cyclohexane, benzene, toluene, xylene, and ethylbenzene.

11. The method of claim 10, characterized in that, The hydrocarbon solvent is hexane.

12. The method according to claim 1, characterized in that, The terminator is selected from one or more of methanol, ethanol, and butanol.

Images