A neutral borane compound, a method for preparing the same, and use thereof in iron-catalyzed polymerization of conjugated dienes

Abstract

A neutral borane compound, a preparation method thereof and application of the compound in iron-catalyzed conjugated diene polymerization. The present application belongs to the field of iron-based catalytic olefin polymerization. The purpose of the present application is to solve the technical problems of poor thermal stability of boron salt, high cost of boron salt preparation and high unit consumption caused by high molecular weight of polymer in the existing conjugated olefin polymerization system. The preparation process of the neutral borane compound provided by the present application is simple, the production cost is low, and because the polarity of the compound is smaller, the solubility in alkane is better, which can promote the efficient progress of the polymerization reaction. In addition, the neutral borane compound provided by the present application is more electron-rich than the tri(pentafluorophenyl)borane compound, so it has better thermal stability under the same conditions, is more conducive to preservation during use, is conducive to cost reduction, and is more conducive to industrial production.

Description

Technical Field

[0001] This invention belongs to the field of iron-based catalytic polymerization, specifically relating to a neutral borane compound, its preparation method, and its application in iron-catalyzed conjugated diene polymerization. Background Technology

[0002] Global annual production of natural rubber is limited by geographical environment, climate conditions, and planting cycle, making it difficult to meet the growing demand for elastomer materials from modern industry. Therefore, developing efficient synthetic rubber catalytic systems has become a key research focus.

[0003] Currently, coordination polymerization technology for preparing high-performance synthetic rubber from transition metal-catalyzed conjugated dienes mainly utilizes macrolides (MAO) and tris(pentafluorophenyl)borane compounds. MAO exhibits high catalytic activity, but it requires toluene as a co-solvent, which contradicts the development of green and low-carbon polymerization processes. Furthermore, the large quantity and high cost of MAO in solution polymerization hinder its industrialization. Therefore, scientists have developed tris(pentafluorophenyl)borane compounds with similar activity that are soluble in alkane solvents to replace MAO as a co-catalyst. While this addresses some of the problems associated with toluene as a solvent, bottlenecks remain, including poor thermal stability of boron salts, high boron salt preparation costs, and high unit consumption due to the large molecular weight of the polymer, thus affecting its large-scale industrial application.

[0004] Therefore, in the current industrial production of high-performance synthetic rubber using transition metal-catalyzed conjugated dienes, there is an urgent need to develop a novel transition metal-catalyzed olefin polymerization co-catalyst. This co-catalyst should possess characteristics such as high activity, low cost, good solubility, and small molecular weight to meet the requirements of the synthetic rubber industry for an efficient and economical catalytic system. Summary of the Invention

[0005] The purpose of this invention is to address the technical problems of tris(pentafluorophenyl)boron compounds in existing conjugated olefin polymerization systems, such as poor thermal stability of boron salts, high boron salt preparation costs, and high unit consumption due to large polymer molecular weight. This invention provides a neutral borane compound, its preparation method, and its application in iron-catalyzed conjugated diene polymerization. This neutral borane compound enables efficient, low-molecular-weight, controllable polymerization of conjugated dienes, providing an efficient and economical catalytic solution for the field of conjugated olefin polymerization.

[0006] The technical solution of the present invention is as follows:

[0007] One objective of this invention is to provide a neutral borane compound, wherein the general structural formula of the neutral borane compound is:

[0008]

[0009] In the formula, R1, R2, R3, R4, and R5 are each independently selected from one of H, F, Cl, and CF3, and R1, R2, R3, R4, and R5 are not all H at the same time.

[0010] Preferably, the boron salt compound is selected from one of formulas B1 to B15:

[0011]

[0012]

[0013] A second objective of this invention is to provide a method for preparing the above-mentioned neutral borane compound, wherein the preparation method is carried out according to the following steps:

[0014] S1: Under an argon atmosphere, first add 1,2-dibromoethane and anhydrous organic solvent to a Schlenk tube and stir until homogeneous. Then add magnesium shavings and stir at room temperature until bubbles are generated.

[0015] S2: Transfer the Schlenk tube to a cryogenic reactor, add substituted bromobenzene, and after the addition is complete, stir for a period of time. Add boron trihalide to the Schlenk tube under an argon atmosphere and stir for a certain period of time. Maintain the temperature of the entire reaction system below 0°C throughout the process, then restore to room temperature and continue stirring for a certain period of time. After the reaction is complete, filter and collect the organic phase, dry it and remove the organic solvent to obtain a neutral borane compound.

[0016] Preferably, the anhydrous organic solvent in S1 is one or more of diethyl ether, tetrahydrofuran, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, n-hexane, cyclohexane, dichloromethane, toluene, and ethylbenzene; more preferably, the organic solvent is diethyl ether.

[0017] Preferably, the molar ratio of magnesium to 1,2-dibromoethane in S1 is (0.005-0.015):1; more preferably, the molar ratio of magnesium to 1,2-dibromoethane in S1 is 0.01:1.

[0018] Preferably, the structural formula of the substituted bromobenzene in S2 is:

[0019]

[0020] Among them, R1, R2, R3, R4, and R5 are each independently selected from one of H, F, Cl, and CF3, and R1, R2, R3, R4, and R5 are not all H at the same time.

[0021] Preferably, the boron trihalide in S2 is one or more of boron trifluoride, boron trichloride, or boron tribromide; more preferably, the boron trihalide is boron trifluoride.

[0022] Preferably, below 0°C in S2 means -20 to 0°C; more preferably, the temperature is maintained at -20°C.

[0023] Preferably, the dropping rate of the substituted bromobenzene in S2 is 1-20 drops / min; more preferably, the dropping rate of the substituted bromobenzene is 10 drops / min.

[0024] Preferably, the stirring time is >0.1h after the substituted bromobenzene in S2 is completely added; more preferably, the stirring time is 0.3h.

[0025] Preferably, the stirring time after adding boron trihalide to S2 is >1 hour; more preferably, the stirring time is 2 hours.

[0026] Preferably, the stirring time after the temperature in S2 returns to room temperature is 5-48 hours; more preferably, the stirring time is 24 hours.

[0027] Preferably, the molar ratio of substituted bromobenzene to boron trihalide in S2 is (3.0-3.2):1; more preferably, the molar ratio of substituted bromobenzene to boron trihalide is 3.0:1.

[0028] A third objective of this invention is to provide an application of the above-mentioned neutral borane compound as a co-catalyst in iron-catalyzed conjugated diene polymerization.

[0029] The polymerization method steps are as follows:

[0030] Under anhydrous and oxygen-free conditions, solvent, conjugated diene monomer, alkyl aluminum, iron catalyst and neutral borane compound are added sequentially to the reactor. The polymerization reaction is carried out by stirring at 0-100℃ for 10-120 min. After the reaction is completed, quencher and anti-aging agent are added. After washing, the product is vacuum dried to constant weight to obtain the conjugated diene polymer.

[0031] Preferably, the general structural formula of the iron catalyst is:

[0032]

[0033] Wherein, R6 and R7 are alkyl, aryl, substituted alkyl, substituted aryl, alkoxy, nitrogen-containing or sulfur-containing substituents, and X is isooctanoic acid (EHA-) or neodecanoic acid (NDA-), wherein EHA- is NDA - for More preferably, the iron catalyst has one of the following structures:

[0034]

[0035] Preferably, the alkyl aluminum is one or more selected from diethylaluminum chloride, diethylaluminum chloride, trimethylaluminum, triethylaluminum, tripropylaluminum, tributylaluminum, triisobutylaluminum, triisopropylaluminum, and diisobutylaluminum hydride; more preferably, the alkyl aluminum is one or more selected from triethylaluminum and triisobutylaluminum. Most preferably, it is triethylaluminum.

[0036] Preferably, the conjugated diene monomer is at least one of 1,3-butadiene, isoprene, and bio-based terpenes.

[0037] More preferably, the bio-based terpene is a monoterpene or a sesquiterpene.

[0038] More preferably, the monoterpene is at least one of α-myrcene and β-myrcene, and the sesquiterpene is at least one of α-farnesene and β-farnesene;

[0039] More preferably, the monoterpene is β-myrcene and the sesquiterpene is β-farnesene.

[0040] Preferably, the solvent is one or more of toluene, xylene, chlorobenzene, petroleum ether, n-hexane, and cyclohexane; more preferably, the solvent is cyclohexane.

[0041] Preferably, the volume ratio of solvent to monomer is (1-15):1; more preferably, the volume ratio of solvent to monomer is (3-10):1; and most preferably, the volume ratio of solvent to monomer is 10:1.

[0042] Preferably, the molar ratio of the monomer to the iron catalyst is (100-50000):1; more preferably, the molar ratio of the monomer to the iron catalyst is (1000-20000):1; and most preferably, the molar ratio of the monomer to the iron catalyst is 15000:1.

[0043] Preferably, the molar ratio of boron in the neutral borane compound to iron in the iron catalyst is (0.1-20):1; more preferably, the molar ratio of boron in the neutral borane compound to iron in the iron catalyst is (0.1-1):1; most preferably, the molar ratio of boron in the neutral borane compound to iron in the iron catalyst is 0.3:1.

[0044] Preferably, the molar ratio of aluminum in the alkylaluminum to iron in the iron catalyst is (10-100):1; more preferably, the molar ratio is (20-60):1. Most preferably, the molar ratio is 40:1.

[0045] Preferably, the reaction temperature is 30–90°C and the reaction time is 30–120 min; more preferably, the reaction temperature is 40°C and the reaction time is 60 min.

[0046] The fourth objective of this invention is to provide a rubber material obtained by the above-mentioned application method, wherein the number average molecular weight of the rubber material is 200,000-1,000,000 g / mol, the molecular weight distribution is 1.5-5.0, the molar content of 3,4-structure in the conjugated diene polymer unit is 30-80% and / or the molar content of 1,2-structure is 30-60%, and the glass transition temperature of the raw rubber is in the range of -80 to 10℃.

[0047] Preferably, the rubber material has a molecular weight distribution of 2.5-3.0, the molar content of 3,4-structure in the conjugated diene polymer unit is 34-78% and / or the molar content of 1,2-structure is 57-62%, and the glass transition temperature of the raw rubber is in the range of -70 to -7℃.

[0048] The fifth objective of this invention is to provide a vulcanization method for the above-mentioned rubber material, wherein the method includes:

[0049] Weigh out 100 parts of conjugated diene polymer, 50-150 parts of silica, 1-60 parts of carbon black, 1-3 parts of vulcanizing accelerator, 0.1-10 parts of vulcanizing agent, and 1-5 parts of zinc stearate by mass, mix and knead.

[0050] Preferably, the carbon black is one or more of N660, N550, N324, N330, and N110.

[0051] Preferably, the vulcanizing agent is one or more of TMTD, CZ, M, ZDMC, and ZBX.

[0052] Preferably, the vulcanizing agent is sulfur.

[0053] The sixth objective of this invention is to provide a vulcanized rubber prepared by the above method, wherein the vulcanized rubber has a tensile strength > 16 MPa, an elongation at break > 300%, and a stress at 300% constant elongation > 6 MPa.

[0054] Preferably, the vulcanized rubber has a tensile strength > 17 MPa, an elongation at break > 450%, and a stress at 300% constant elongation > 8 MPa.

[0055] The seventh objective of this invention is to provide an application of the vulcanized rubber prepared by the above method in tire manufacturing, noise reduction and damping, and shock absorption.

[0056] The advantages of this invention compared to existing technologies are:

[0057] (1) The preparation process of the neutral borane compound provided by the present invention is simple and the production cost is low. Compared with the purchase price of raw materials for the preparation of tri(pentafluorophenyl)borate compounds, such as pentafluorobromobenzene, which is 480,000 yuan / ton; under the preparation method proposed in the present invention, the purchase price of raw materials for the preparation of neutral borane compounds, such as 3,4,5-trifluorobromobenzene, is 300,000 yuan / ton, and the purchase price of 3,5-ditrifluoromethylbromobenzene is 180,000 tons. In comparison, the preparation cost of the co-catalyst of the present application is greatly reduced.

[0058] (2) The neutral borane compound provided by the present invention has lower polarity than tris(pentafluorophenyl)borane compound, and has better solubility in alkane solubility, which can promote the efficient progress of polymerization reaction. In addition, the neutral borane compound provided by the present invention is more electron-rich than tris(pentafluorophenyl)borane compound, so it has better thermal stability under the same conditions, which is more conducive to storage during use and helps to reduce costs.

[0059] (3) The neutral borane compound provided by the present invention has a better control effect on the polymerization reaction. When the amount of neutral borane compound added is 0.3 equivalents and the monomer concentration reaches 15%, the polymerization product still has good fluidity. Compared with the polymerization product obtained by traditional tri(pentafluorophenyl)borane compound, the molecular weight of the polymerization product of the present invention is significantly reduced. Attached Figure Description

[0060] Figure 1 The isoprene homopolymer obtained in Example 16 1 H NMR spectrum;

[0061] Figure 2 The GPC spectrum of the isoprene homopolymer obtained in Example 16 is shown below.

[0062] Figure 3 The DSC spectrum of the isoprene homopolymer obtained in Example 16 is shown below.

[0063] Figure 4 This is a schematic diagram illustrating the flow properties of the isoprene homopolymer obtained in Example 48;

[0064] Figure 5 This is a schematic diagram showing the flow properties of the isoprene homopolymer obtained in Comparative Example 1. Detailed Implementation

[0065] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0066] Unless otherwise specified, the experimental methods used in the following examples are conventional methods. Unless otherwise specified, the materials, reagents, methods, and instruments used are all conventional materials, reagents, methods, and instruments in the art, and can be obtained commercially by those skilled in the art.

[0067] According to the present invention, the polymerization reactions are all carried out under an inert atmosphere, such as one or more inert atmospheres such as nitrogen, helium, and argon.

[0068] Preparation examples of neutral borane compounds

[0069] Example 1: The preparation method of the neutral borane compound in this example is as follows:

[0070] S1: Under an argon atmosphere, first add 0.08 mL of 1,2-dibromoethane (0.9 mmol, 0.036 equiv.) and 200.0 mL of anhydrous diethyl ether to a Schlenk tube and stir until homogeneous. Then add 2.16 g of magnesium shavings (90 mmol, 3.6 equiv.) and dissolve them in the solvent system. Stir at room temperature until bubbles are generated.

[0071] S2: Transfer the Schlenk tube to a cryogenic reactor and add 13.1 g of 1-bromo-4-fluorobenzene (75 mmol, 3 equiv.) at a dropping rate of 10 drops / min. After the addition is complete, stir for 0.3 h. Then, under an argon atmosphere, add 1.7 g of boron trifluoride (25 mmol, 1 equiv.) to the Schlenk tube and stir for 2 h, maintaining the temperature of the entire reaction system at -20 °C throughout the process. Then, allow it to return to room temperature and stir for 24 h.

[0072] S3: After the reaction was completed as detected by TLC, the organic phase was collected by filtration, dried, and the organic solvent was removed to obtain neutral boron compound B1, whose structure is as follows:

[0073]

[0074] Example 2: The preparation method of the neutral borane compound in this example is as follows:

[0075] S1: Under an argon atmosphere, first add 0.08 mL of 1,2-dibromoethane (0.9 mmol, 0.036 equiv.) and 200.0 mL of anhydrous diethyl ether to a Schlenk tube and stir until homogeneous. Then add 2.16 g of magnesium shavings (90 mmol, 3.6 equiv.) and dissolve them in the solvent system. Stir at room temperature until bubbles are generated.

[0076] S2: Transfer the Schlenk tube to a cryogenic reactor and add 14.4 g of 1-bromo-4-chlorobenzene (75 mmol, 3 equiv.) at a dropping rate of 10 drops / min. After the addition is complete, stir for 0.3 h. Then, under an argon atmosphere, add 1.7 g of boron trifluoride (25 mmol, 1 equiv.) to the Schlenk tube and stir for 2 h, maintaining the temperature of the entire reaction system at -20 °C throughout the process. Then, allow it to return to room temperature and stir for 24 h.

[0077] S3: After the reaction was completed as detected by TLC, the organic phase was collected by filtration, dried, and the organic solvent was removed to obtain neutral boron compound B2, whose structure is as follows:

[0078]

[0079] Example 3: The preparation method of the neutral borane compound in this example is as follows:

[0080] S1: Under an argon atmosphere, first add 0.08 mL of 1,2-dibromoethane (0.9 mmol, 0.036 equiv.) and 200.0 mL of anhydrous diethyl ether to a Schlenk tube and stir until homogeneous. Then add 2.16 g of magnesium shavings (90 mmol, 3.6 equiv.) and dissolve them in the solvent system. Stir at room temperature until bubbles are generated.

[0081] S2: Transfer the Schlenk tube to a cryogenic reactor and add 16.8 g of 1-bromo-4-(trifluoromethyl)benzene (75 mmol, 3 equiv.) at a dropping rate of 10 drops / min. After the addition is complete, stir for 0.3 h. Then, under an argon atmosphere, add 1.7 g of boron trifluoride (25 mmol, 1 equiv.) to the Schlenk tube and stir for 2 h, maintaining the temperature of the entire reaction system at -20 °C throughout the process. Then, allow it to return to room temperature and stir for 24 h.

[0082] S3: After the reaction was completed as detected by TLC, the organic phase was collected by filtration, dried, and the organic solvent was removed to obtain neutral boron compound B3, whose structure is as follows:

[0083]

[0084] Example 4: The preparation method of the neutral borane compound in this example is as follows:

[0085] S1: Preparation of Grignard reagent: Under an argon atmosphere, first add 0.08 mL of 1,2-dibromoethane (0.9 mmol, 0.036 equiv.) and 200.0 mL of anhydrous diethyl ether to a Schlenk tube and stir until homogeneous. Then add 2.16 g of magnesium shavings (90 mmol, 3.6 equiv.) and dissolve them in the solvent system. Stir at room temperature until bubbles are generated.

[0086] S2: Transfer the Schlenk tube to a cryogenic reactor and add 14.4 g of 1-bromo-3,5-difluorobenzene (75 mmol, 3 equiv.) at a dropping rate of 10 drops / min. After the addition is complete, stir for 0.3 h. Then, under an argon atmosphere, add 1.7 g of boron trifluoride (25 mmol, 1 equiv.) to the Schlenk tube and stir for 2 h, maintaining the temperature of the entire reaction system at -20 °C throughout the process. Then, allow it to return to room temperature and stir for 24 h.

[0087] S3: After the reaction was completed as detected by TLC, the organic phase was collected by filtration, dried, and the organic solvent was removed to obtain neutral boron compound B4, whose structure is as follows:

[0088]

[0089] Example 5: The preparation method of the neutral borane compound in this example is as follows:

[0090] S1: Under an argon atmosphere, first add 0.08 mL of 1,2-dibromoethane (0.9 mmol, 0.036 equiv.) and 200.0 mL of anhydrous diethyl ether to a Schlenk tube and stir until homogeneous. Then add 2.16 g of magnesium shavings (90 mmol, 3.6 equiv.) and dissolve them in the solvent system. Stir at room temperature until bubbles are generated.

[0091] S2: Transfer the Schlenk tube to a cryogenic reactor and add 17.1 g of 1-bromo-3,5-dichlorobenzene (75 mmol, 3 equiv.) at a dropping rate of 10 drops / min. After the addition is complete, stir for 0.3 h. Then, under an argon atmosphere, add 1.7 g of boron trifluoride (25 mmol, 1 equiv.) to the Schlenk tube and stir for 2 h, maintaining the temperature of the entire reaction system at -20 °C throughout the process. Then, allow it to return to room temperature and stir for 24 h.

[0092] S3: After the reaction was completed as detected by TLC, the organic phase was collected by filtration, dried, and the organic solvent was removed to obtain neutral boron compound B5, whose structure is as follows:

[0093]

[0094] Example 6: The preparation method of the neutral borane compound in this example is as follows:

[0095] S1: Under an argon atmosphere, first add 0.08 mL of 1,2-dibromoethane (0.9 mmol, 0.036 equiv.) and 200.0 mL of anhydrous diethyl ether to a Schlenk tube and stir until homogeneous. Then add 2.16 g of magnesium shavings (90 mmol, 3.6 equiv.) and dissolve them in the solvent system. Stir at room temperature until bubbles are generated.

[0096] S2: Transfer the Schlenk tube to a cryogenic reactor and add 21.9 g of 1-bromo-3,5-bis(trifluoromethyl)benzene (75 mmol, 3 equiv.) at a dropping rate of 10 drops / min. After the addition is complete, stir for 0.3 h. Then, under an argon atmosphere, add 1.7 g of boron trifluoride (25 mmol, 1 equiv.) to the Schlenk tube and stir for 2 h, maintaining the temperature of the entire reaction system at -20 °C throughout the process. Then, allow it to return to room temperature and stir for 24 h.

[0097] S3: After the reaction was completed as detected by TLC, the organic phase was collected by filtration, dried, and the organic solvent was removed to obtain neutral boron compound B6, whose structure is as follows:

[0098]

[0099] Example 7: The preparation method of the neutral borane compound in this example is as follows:

[0100] S1: Under an argon atmosphere, first add 0.08 mL of 1,2-dibromoethane (0.9 mmol, 0.036 equiv.) and 200.0 mL of anhydrous diethyl ether to a Schlenk tube and stir until homogeneous. Then add 2.16 g of magnesium shavings (90 mmol, 3.6 equiv.) and dissolve them in the solvent system. Stir at room temperature until bubbles are generated.

[0101] S2: Transfer the Schlenk tube to a cryogenic reactor and add 14.4 g of 2-bromo-1,3-difluorobenzene (75 mmol, 3 equiv.) at a dropping rate of 10 drops / min. After the addition is complete, stir for 0.3 h. Then, under an argon atmosphere, add 1.7 g of boron trifluoride (25 mmol, 1 equiv.) to the Schlenk tube and stir for 2 h, maintaining the temperature of the entire reaction system at -20 °C throughout the process. Then, allow it to return to room temperature and stir for 24 h.

[0102] S3: After the reaction was completed as detected by TLC, the organic phase was collected by filtration, dried, and the organic solvent was removed to obtain neutral boron compound B7, whose structure is as follows:

[0103]

[0104] Example 8: The preparation method of the neutral borane compound in this example is as follows:

[0105] S1: Under an argon atmosphere, first add 0.08 mL of 1,2-dibromoethane (0.9 mmol, 0.036 equiv.) and 200.0 mL of anhydrous diethyl ether to a Schlenk tube and stir until homogeneous. Then add 2.16 g of magnesium shavings (90 mmol, 3.6 equiv.) and dissolve them in the solvent system. Stir at room temperature until bubbles are generated.

[0106] S2: Transfer the Schlenk tube to a cryogenic reactor and add 17.1 g of 2-bromo-1,3-dichlorobenzene (75 mmol, 3 equiv.) at a dropping rate of 10 drops / min. After the addition is complete, stir for 0.3 h. Then, under an argon atmosphere, add 1.7 g of boron trifluoride (25 mmol, 1 equiv.) to the Schlenk tube and stir for 2 h, maintaining the temperature of the entire reaction system at -20 °C throughout the process. Then, allow it to return to room temperature and stir for 24 h.

[0107] S3: After the reaction was completed as detected by TLC, the organic phase was collected by filtration, dried, and the organic solvent was removed to obtain neutral boron compound B8, whose structure is as follows:

[0108]

[0109] Example 9: The preparation method of the neutral borane compound in this example is as follows:

[0110] S1: Under an argon atmosphere, first add 0.08 mL of 1,2-dibromoethane (0.9 mmol, 0.036 equiv.) and 200.0 mL of anhydrous diethyl ether to a Schlenk tube and stir until homogeneous. Then add 2.16 g of magnesium shavings (90 mmol, 3.6 equiv.) and dissolve them in the solvent system. Stir at room temperature until bubbles are generated.

[0111] S2: Transfer the Schlenk tube to a cryogenic reactor and add 21.9 g of 2-bromo-1,3-bis(trifluoromethyl)benzene (75 mmol, 3 equiv.) at a dropping rate of 10 drops / min. After the addition is complete, stir for 0.3 h. Then, under an argon atmosphere, add 1.7 g of boron trifluoride (25 mmol, 1 equiv.) to the Schlenk tube and stir for 2 h, maintaining the temperature of the entire reaction system at -20 °C throughout the process. Then, allow it to return to room temperature and stir for 24 h.

[0112] S3: After the reaction was completed as detected by TLC, the organic phase was collected by filtration, dried, and the organic solvent was removed to obtain neutral boron compound B9, whose structure is as follows:

[0113]

[0114] Example 10: The preparation method of the neutral borane compound in this example is as follows:

[0115] S1: Under an argon atmosphere, first add 0.08 mL of 1,2-dibromoethane (0.9 mmol, 0.036 equiv.) and 200.0 mL of anhydrous diethyl ether to a Schlenk tube and stir until homogeneous. Then add 2.16 g of magnesium shavings (90 mmol, 3.6 equiv.) and dissolve them in the solvent system. Stir at room temperature until bubbles are generated.

[0116] S2: Transfer the Schlenk tube to a cryogenic reactor and add 15.9 g of 2-bromo-1,3,5-trifluorobenzene (75 mmol, 3 equiv.) at a dropping rate of 10 drops / min. After the addition is complete, stir for 0.3 h. Then, under an argon atmosphere, add 1.7 g of boron trifluoride (25 mmol, 1 equiv.) to the Schlenk tube and stir for 2 h, maintaining the temperature of the entire reaction system at -20 °C throughout the process. Then, allow it to return to room temperature and stir for 24 h.

[0117] S3: After the reaction was completed as detected by TLC, the organic phase was collected by filtration, dried, and the organic solvent was removed to obtain neutral boron compound B10, whose structure is as follows:

[0118]

[0119] Example 11: The preparation method of the neutral borane compound in this example is as follows:

[0120] S1: Under an argon atmosphere, first add 0.08 mL of 1,2-dibromoethane (0.9 mmol, 0.036 equiv.) and 200.0 mL of anhydrous diethyl ether to a Schlenk tube and stir until homogeneous. Then add 2.16 g of magnesium shavings (90 mmol, 3.6 equiv.) and dissolve them in the solvent system. Stir at room temperature until bubbles are generated.

[0121] S2: Transfer the Schlenk tube to a cryogenic reactor and add 19.5 g of 2-bromo-1,3,5-trichlorobenzene (75 mmol, 3 equiv.) at a dropping rate of 10 drops / min. After the addition is complete, stir for 0.3 h. Then, under an argon atmosphere, add 1.7 g of boron trifluoride (25 mmol, 1 equiv.) to the Schlenk tube and stir for 2 h, maintaining the temperature of the entire reaction system at -20 °C throughout the process. Then, allow it to return to room temperature and stir for 24 h.

[0122] S3: After the reaction was completed as detected by TLC, the organic phase was collected by filtration, dried, and the organic solvent was removed to obtain neutral boron compound B11, whose structure is as follows:

[0123]

[0124] Example 12: The preparation method of the neutral borane compound in this example is as follows:

[0125] S1: Under an argon atmosphere, first add 0.08 mL of 1,2-dibromoethane (0.9 mmol, 0.036 equiv.) and 200.0 mL of anhydrous diethyl ether to a Schlenk tube and stir until homogeneous. Then add 2.16 g of magnesium shavings (90 mmol, 3.6 equiv.) and dissolve them in the solvent system. Stir at room temperature until bubbles are generated.

[0126] S2: Transfer the Schlenk tube to a cryogenic reactor and add 27 g of 2-bromo-1,3,5-tris(trifluoromethyl)benzene (75 mmol, 3 equiv.) at a dropping rate of 10 drops / min. After the addition is complete, stir for 0.3 h. Then, under an argon atmosphere, add 1.7 g of boron trifluoride (25 mmol, 1 equiv.) to the Schlenk tube and stir for 2 h, maintaining the temperature of the entire reaction system at -20 °C throughout the process. Then, allow it to return to room temperature and stir for 24 h.

[0127] S3: After the reaction was completed as detected by TLC, the organic phase was collected by filtration, dried, and the organic solvent was removed to obtain the neutral boron compound B12, whose structure is as follows:

[0128]

[0129] Example 13: The preparation method of the neutral borane compound in this example is as follows:

[0130] S1: Under an argon atmosphere, first add 0.08 mL of 1,2-dibromoethane (0.9 mmol, 0.036 equiv.) and 200.0 mL of anhydrous diethyl ether to a Schlenk tube and stir until homogeneous. Then add 2.16 g of magnesium shavings (90 mmol, 3.6 equiv.) and dissolve them in the solvent system. Stir at room temperature until bubbles are generated.

[0131] S2: Transfer the Schlenk tube to a cryogenic reactor and add 15.9 g of 1-bromo-3,4,5-trifluorobenzene (75 mmol, 3 equiv.) at a dropping rate of 10 drops / min. After the addition is complete, stir for 0.3 h. Then, under an argon atmosphere, add 1.7 g of boron trifluoride (25 mmol, 1 equiv.) to the Schlenk tube and stir for 2 h, maintaining the temperature of the entire reaction system at -20 °C throughout the process. Then, allow it to return to room temperature and stir for 24 h.

[0132] S3: After the reaction was completed as detected by TLC, the organic phase was collected by filtration, dried, and the organic solvent was removed to obtain neutral boron compound B13, whose structure is as follows:

[0133]

[0134] Example 14: The preparation method of the neutral borane compound in this example is as follows:

[0135] S1: Under an argon atmosphere, first add 0.08 mL of 1,2-dibromoethane (0.9 mmol, 0.036 equiv.) and 200.0 mL of anhydrous diethyl ether to a Schlenk tube and stir until homogeneous. Then add 2.16 g of magnesium shavings (90 mmol, 3.6 equiv.) and dissolve them in the solvent system. Stir at room temperature until bubbles are generated.

[0136] S2: Transfer the Schlenk tube to a cryogenic reactor and add 19.5 g of 1-bromo-3,4,5-trichlorobenzene (75 mmol, 3 equiv.) at a dropping rate of 10 drops / min. After the addition is complete, stir for 0.3 h. Then, under an argon atmosphere, add 1.7 g of boron trifluoride (25 mmol, 1 equiv.) to the Schlenk tube and stir for 2 h, maintaining the temperature of the entire reaction system at -20 °C throughout the process. Then, restore the temperature and stir for 24 h.

[0137] S3: After the reaction was completed as detected by TLC, the organic phase was collected by filtration, dried, and the organic solvent was removed to obtain neutral boron compound B14, whose structure is as follows:

[0138]

[0139] Example 15: The preparation method of the neutral borane compound in this example is as follows:

[0140] S1: Under an argon atmosphere, first add 0.08 mL of 1,2-dibromoethane (0.9 mmol, 0.036 equiv.) and 200.0 mL of anhydrous diethyl ether to a Schlenk tube and stir until homogeneous. Then add 2.16 g of magnesium shavings (90 mmol, 3.6 equiv.) and dissolve them in the solvent system. Stir at room temperature until bubbles are generated.

[0141] S2: Transfer the Schlenk tube to a cryogenic reactor and add 27 g of 1-bromo-3,4,5-tris(trifluoromethyl)benzene (75 mmol, 3 equiv.) at a dropping rate of 10 drops / min. After the addition is complete, stir for 0.3 h. Then, under an argon atmosphere, add 1.7 g of boron trifluoride (25 mmol, 1 equiv.) to the Schlenk tube and stir for 2 h, maintaining the temperature of the entire reaction system at -20 °C throughout the process. Then, allow it to return to room temperature and stir for 24 h.

[0142] S3: After the reaction was completed as detected by TLC, the organic phase was collected by filtration, dried, and the organic solvent was removed to obtain neutral boron compound B15, whose structure is as follows:

[0143]

[0144] Catalytic conjugated diene polymerization examples

[0145] Examples 16-30 investigate the effects of different neutral borane compound systems on the polymerization of conjugated dienes.

[0146] Example 16:

[0147] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B1 (0.9 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0148] Preparation of vulcanized rubber: Weigh 100 parts by weight of the elastomer polymer of Example 16, 50 parts of N324, 70 parts of fumed silica, 1.2 parts of vulcanizing agent CZ, 1.5 parts of sulfur, and 5 parts of zinc stearate, and obtain vulcanized rubber by mixing and vulcanization.

[0149] Example 17:

[0150] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B2 (1.0 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0151] Example 18:

[0152] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B3 (1.4 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0153] Example 19:

[0154] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B4 (1.1 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0155] Example 20:

[0156] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B5 (1.1 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0157] Example 21:

[0158] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0159] Example 22:

[0160] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B7 (1.1 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0161] Example 23:

[0162] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B8 (1.1 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0163] Example 24:

[0164] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B9 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0165] Example 25:

[0166] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B10 (1.2 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0167] Example 26:

[0168] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B11 (1.7 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0169] Example 27:

[0170] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B12 (2.6 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0171] Example 28:

[0172] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B13 (1.2 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0173] Example 29:

[0174] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B14 (1.3 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0175] Example 30:

[0176] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B15 (2.6 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0177] Examples 16 and 31-37 investigate the effects of different iron catalysts on the polymerization of conjugated dienes.

[0178] Example 31:

[0179] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-1 (7.8 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0180] Example 32:

[0181] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-2 (8.6 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0182] Example 33:

[0183] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-3 (8.0 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0184] Example 34:

[0185] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-4 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0186] Example 35:

[0187] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-5 (8.0 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0188] Example 36:

[0189] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-6 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0190] Example 37:

[0191] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-8 (8.0 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0192] Examples 16, 38-45, investigate the effects of different polymerizing monomers on iron-based catalytic polymerization.

[0193] Example 38:

[0194] Under an argon atmosphere, anhydrous cyclohexane (134 mL), 1,3-butadiene (13.4 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0195] Example 39:

[0196] Under an argon atmosphere, anhydrous cyclohexane (250 mL), β-myrcene (25.6 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 500 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0197] Preparation of vulcanized rubber: Weigh 100 parts by weight of the elastomer polymer of Example 39, 50 parts of N324, 70 parts of fumed silica, 1.2 parts of vulcanizing agent CZ, 1.5 parts of sulfur, and 5 parts of zinc stearate, and obtain vulcanized rubber by mixing and vulcanization.

[0198] Example 40:

[0199] Under an argon atmosphere, anhydrous cyclohexane (410 mL), β-farnesene (41.3 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 1000 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0200] Preparation of vulcanized rubber: Weigh 100 parts by weight of the elastomer polymer of Example 40, 50 parts of N324, 70 parts of fumed silica, 1.2 parts of vulcanizing agent CZ, 1.5 parts of sulfur, and 5 parts of zinc stearate, and obtain vulcanized rubber by mixing and vulcanization.

[0201] Example 41:

[0202] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (10.5 mL, 105 mmol, 10500 equiv.), 1,3-butadiene (4 mL, 45 mmol, 4500 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0203] Preparation of vulcanized rubber: Weigh 100 parts by weight of the elastomer polymer of Example 41, 50 parts of N324, 70 parts of fumed silica, 1.2 parts of vulcanizing agent CZ, 1.5 parts of sulfur, and 5 parts of zinc stearate, and obtain vulcanized rubber by mixing and vulcanization.

[0204] Example 42:

[0205] Under an argon atmosphere, anhydrous cyclohexane (180 mL), isoprene (13.5 mL, 135 mmol, 13500 equiv.), β-myrcene (2.6 mL, 15 mmol, 1500 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0206] Preparation of vulcanized rubber: Weigh 100 parts by weight of the elastomer polymer of Example 42, 50 parts of N324, 70 parts of fumed silica, 1.2 parts of vulcanizing agent CZ, 1.5 parts of sulfur, and 5 parts of zinc stearate, and obtain vulcanized rubber by mixing and vulcanization.

[0207] Example 43:

[0208] Under an argon atmosphere, anhydrous cyclohexane (180 mL), isoprene (13.5 mL, 135 mmol, 13500 equiv.), β-farnesene (4.2 mL, 15 mmol, 1500 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0209] Preparation of vulcanized rubber: Weigh 100 parts by weight of the elastomer polymer of Example 43, 50 parts of N324, 70 parts of fumed silica, 1.2 parts of vulcanizing agent CZ, 1.5 parts of sulfur, and 5 parts of zinc stearate, and obtain vulcanized rubber by mixing and vulcanization.

[0210] Example 44:

[0211] Under an argon atmosphere, anhydrous cyclohexane (180 mL), 1,3-butadiene (12 mL, 135 mmol, 13500 equiv.), β-myrcene (1.3 mL, 7.5 mmol, 750 equiv.), β-farnesene (2.1 mL, 7.5 mmol, 750 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min, and then the reaction was terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the clear liquid, the polymer was washed three times with ethanol, and the resulting polymer was vacuum dried at 40°C to constant weight to obtain the elastomer polymer.

[0212] Preparation of vulcanized rubber: Weigh 100 parts by weight of the elastomer polymer of Example 44, 50 parts of N324, 70 parts of fumed silica, 1.2 parts of vulcanizing agent CZ, 1.5 parts of sulfur, and 5 parts of zinc stearate, and obtain vulcanized rubber by mixing and vulcanization.

[0213] Example 45:

[0214] Under an argon atmosphere, anhydrous cyclohexane (180 mL), isoprene (6.75 mL, 67.5 mmol, 6750 equiv.), 1,3-butadiene (6 mL, 67.5 mmol, 6750 equiv.), β-myrcene (1.3 mL, 7.5 mmol, 750 equiv.), β-farnesene (2.1 mL, 7.5 mmol, 750 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min, and then the reaction was terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the clear liquid, the polymer was washed three times with ethanol, and the resulting polymer was vacuum dried at 40°C to constant weight to obtain the elastomer polymer.

[0215] Preparation of vulcanized rubber: Weigh 100 parts by weight of the elastomer polymer of Example 45, 50 parts of N324, 70 parts of fumed silica, 1.2 parts of vulcanizing agent CZ, 1.5 parts of sulfur, and 5 parts of zinc stearate, and obtain vulcanized rubber by mixing and vulcanization.

[0216] Examples 16 and 46-47 investigate the effect of different amounts of neutral borane compounds on the polymerization of conjugated dienes.

[0217] Example 46:

[0218] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (6.4 mg, 10 μmol, 1 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0219] Example 47:

[0220] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (0.6 mg, 1 μmol, 0.1 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0221] Examples 16 and 48 investigate the effect of different monomer concentrations on the polymerization of conjugated dienes.

[0222] Example 48:

[0223] Under an argon atmosphere, anhydrous cyclohexane (85 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0224] Examples 16, 49-51, investigate the effect of different reaction temperatures on the polymerization of conjugated dienes.

[0225] Example 49:

[0226] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 30 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0227] Example 50:

[0228] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 60 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0229] Example 51:

[0230] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 90 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0231] Examples 19 and 52 investigate the effects of different alkyl aluminum groups on the polymerization of conjugated dienes.

[0232] Example 52:

[0233] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triisobutylaluminum (79.3 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound B6 (1.95 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 90 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0234] Comparative Example 1:

[0235] Under an argon atmosphere, anhydrous cyclohexane (150 mL), isoprene (15 mL, 150 mmol, 15000 equiv.), triethylaluminum (46 mg, 0.4 mmol, 40 equiv.), iron catalyst Fe-7 (8.9 mg, 10 μmol, 1 equiv.), and neutral borane compound (1.53 mg, 3 μmol, 0.3 equiv.) were added sequentially to a 250 mL Schlenk tube. Polymerization was carried out at 40 °C for 60 min. The reaction was then terminated with 25 mL of a mixed solution of methanol and hydrochloric acid (MeOH / HCl volume ratio = 50 / 1) and 1 mL of an antioxidant. After discarding the supernatant, the polymer was washed three times with ethanol. The resulting polymer was then vacuum dried at 40 °C to constant weight to obtain the elastomer polymer.

[0236] Preparation of vulcanized rubber: Weigh 100 parts by mass of the elastomer polymer of Comparative Example 1, 50 parts by mass of N324, 70 parts by mass of fumed silica, 1.2 parts by mass of vulcanizing agent CZ, 1.5 parts by mass of sulfur, and 5 parts by mass of zinc stearate. After mixing and vulcanization, vulcanized rubber is obtained.

[0237] The chemical formulas of the neutral borane compounds used in the comparative examples are shown below:

[0238]

[0239] Table 1 Test data of conjugated diene homopolymer elastomer

[0240]

[0241]

[0242] Table 2 Test data of conjugated diene homopolymer elastomers

[0243]

[0244] Table 3 Test data for conjugated diene homopolymer elastomers

[0245]

[0246] Table 4 Test data of conjugated diene homopolymer elastomer

[0247]

[0248] Table 5 Test data for conjugated diene copolymer elastomers

[0249]

[0250] Table 6 Test data for conjugated diene copolymer elastomers

[0251]

[0252] Table 7 Test data for conjugated diene copolymer elastomers

[0253]

[0254] Table 8 Test data for conjugated diene copolymer elastomers

[0255]

[0256] Table 9 Test data for conjugated diene copolymer elastomers

[0257]

[0258]

[0259] Note: In Tables 1-9, IP represents isoprene, BD represents butadiene, MY represents myrcene, and FA represents farnesene.

[0260] Table 10 Performance test data of homopolymers and copolymers of conjugated dienes and bio-based terpenes

[0261]

[0262] The above description is merely a preferred embodiment of the present invention. These specific embodiments are different implementations based on the overall concept of the present invention, and the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A neutral borane compound, characterized in that, The general structural formula is: In the formula, R1, R2, R3, R4, and R5 are each independently selected from one of H, F, Cl, and CF3, and R1, R2, R3, R4, and R5 are not all H at the same time.

2. The neutral borane compound according to claim 1, characterized in that, Boron salt compounds are selected from one of formulas B1 to B15:

3. The method for preparing the neutral borane compound according to claim 1 or 2, characterized in that, The method described: S1: Under an argon atmosphere, first add 1,2-dibromoethane and anhydrous organic solvent to a Schlenk tube and stir until homogeneous. Then add magnesium shavings and stir at room temperature until bubbles are generated. S2: Transfer the Schlenk tube to a cryogenic reactor, add substituted bromobenzene, and after the addition is complete, stir for a period of time. Add boron trihalide to the Schlenk tube under an argon atmosphere and stir for a certain period of time. Maintain the temperature of the entire reaction system below 0°C throughout the process, then restore to room temperature and continue stirring for a certain period of time. After the reaction is complete, filter and collect the organic phase, dry it and remove the organic solvent to obtain a neutral borane compound.

4. The method according to claim 3, characterized in that, The anhydrous organic solvent in S1 is one or more of the following: diethyl ether, tetrahydrofuran, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, n-hexane, cyclohexane, dichloromethane, toluene, and ethylbenzene. The molar ratio of magnesium to 1,2-dibromoethane in S1 is (0.005-0.015):1; the structural formula of the substituted bromobenzene in S2 is: Wherein, R1, R2, R3, R4, and R5 are the same as in claim 1; the boron trihalide in S2 is one or more of boron trifluoride, boron trichloride, or boron tribromide; below 0°C in S2 refers to -20 to 0°C; the dropping rate of the substituted bromobenzene in S2 is 1-20 drops / min; the stirring time after the substituted bromobenzene is added in S2 is >0.1h; the stirring time after the addition of boron trihalide in S2 is >1h; the stirring time after the temperature returns to room temperature in S2 is 5-48h; the molar ratio of the substituted bromobenzene to the boron trihalide in S2 is (3.0-3.2):

1.

5. The application of the neutral borane compound according to claim 1 or 2 as a co-catalyst in iron-catalyzed conjugated diene polymerization, characterized in that, The polymerization method steps are as follows: Under anhydrous and oxygen-free conditions, solvent, conjugated diene monomer, alkyl aluminum, iron catalyst and neutral borane compound are added sequentially to the reactor. The polymerization reaction is carried out by stirring at 0-100℃ for 10-120 min. After the reaction is completed, quencher and anti-aging agent are added. After washing, the product is vacuum dried to constant weight to obtain the conjugated diene polymer.

6. The method according to claim 5, characterized in that, The general structural formula of iron catalysts is: Wherein, R6 and R7 are alkyl, aryl, substituted alkyl, substituted aryl, alkoxy, nitrogen-containing or sulfur-containing substituents, and X is EHA- or NDA-, where EHA- is... NDA - for Alkyl aluminum is one or more of the following: diethylaluminum monochloro, diethylaluminum dichloro, trimethylaluminum, triethylaluminum, tripropylaluminum, tributylaluminum, triisobutylaluminum, triisopropylaluminum, and diisobutylaluminum hydride; The conjugated diene monomer is at least one of 1,3-butadiene, isoprene, and bio-based terpenes, wherein the bio-based terpenes are monoterpenes or sesquiterpenes; The solvent is one or more of toluene, xylene, chlorobenzene, petroleum ether, n-hexane, and cyclohexane.

7. The method according to claim 6, characterized in that, Iron catalysts have one of the following structures: The alkylaluminum is one or more selected from triethylaluminum and triisobutylaluminum. Triethylaluminum is the most preferred. The monoterpene is at least one of α-myrcene and β-myrcene, and the sesquiterpene is at least one of α-farnesene and β-farnesene; The solvent is cyclohexane.

8. The method according to claim 5, characterized in that, The volume ratio of solvent to monomer is (1-15):1; the molar ratio of monomer to iron in iron catalyst is (100-50000):1; the molar ratio of boron in neutral borane compound to iron in iron catalyst is (0.1-20):1; the molar ratio of aluminum in alkylaluminum to iron in iron catalyst is (10-100):1; the reaction temperature is 30-90℃, and the reaction time is 30-120 min.

9. The method according to claim 8, characterized in that, The volume ratio of solvent to monomer is (3-10):1; the molar ratio of monomer to iron in iron catalyst is (1000-20000):1; the molar ratio of boron in neutral borane compound to iron in iron catalyst is (0.1-1):1; the molar ratio of aluminum in alkylaluminum to iron in iron catalyst is (20-60):

1.

10. The rubber material obtained by the application method according to claim 5, characterized in that, The number-average molecular weight of the rubber material is 200,000 g / mol to 1,000,000 g / mol, the molecular weight distribution is 1.5 to 5.0, the molar content of 3,4-structure in the conjugated diene polymer unit is 30 to 80% and / or the molar content of 1,2-structure is 30 to 60%, and the glass transition temperature of the raw rubber is in the range of -80 to 10℃.

11. The vulcanization method for the rubber material according to claim 10, characterized in that, The method described: Weigh out 100 parts of conjugated diene polymer, 50-150 parts of silica, 1-60 parts of carbon black, 1-3 parts of vulcanizing accelerator, 0.1-10 parts of vulcanizing agent, and 1-5 parts of zinc stearate by mass, mix and knead.

12. The vulcanization method according to claim 11, characterized in that, The carbon black is one or more of N660, N550, N324, N330, and N110, the vulcanizing accelerator is one or more of TMTD, CZ, M, ZDMC, and ZBX, and the vulcanizing agent is sulfur.

13. The vulcanized rubber obtained by the method of claim 11 or 12, characterized in that, The vulcanized rubber has a tensile strength >16MPa, an elongation at break >300%, and a stress at 300% elongation >6MPa.

14. The application of the vulcanized rubber of claim 13 in tire manufacturing, noise reduction, damping, and shock absorption.

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