Alpha-diimine nickel complexes, methods of synthesis and use

Abstract

The application provides an alpha-diaimine nickel complex, a synthesis method and application, and the alpha-diaimine nickel complex is used for preparing a high-thermal-stability catalyst of an ultrahigh molecular weight polyethylene thermoplastic elastomer and a POE material, and a structural formula is shown as formula (I). The alpha-diaimine nickel complex has high catalytic activity in catalyzing ethylene polymerization and has good thermal stability. The obtained ultrahigh molecular weight polyethylene has a molecular weight distribution of 1.3-2.5, a molecular weight of 79-833*10 4 g·mol ‑1 , good resistance in catalyzing copolymerization of ethylene and a polar monomer, can produce ultrahigh molecular weight polar polyethylene, and can also catalyze copolymerization of ethylene and 1-octene to prepare a POE (Polyolefin Elastomer) used for high molecular compatibilization blending. The obtained ultrahigh molecular weight polyethylene elastomer has good physical and mechanical properties. The catalyst has ultrahigh catalytic activity, can greatly reduce the production cost of the catalyst, produce high-performance polyethylene, and has great industrial application potential.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of olefin coordination polymerization catalysts and polyolefins, and particularly relates to a super-high-activity catalyst α-diimine nickel complex for synthesizing an ultra-high molecular weight polyethylene thermoplastic elastomer, a synthesis method therefor, and an application thereof. BACKGROUND

[0002] Ultra-high molecular weight polyethylene and POE are both high-end polyolefins, and have many excellent properties. The former has the properties of chemical corrosion resistance, weather resistance, wear resistance, impact resistance, self-lubrication, etc., and has been widely used in biomedical, military equipment, diaphragm battery, etc. industries. The latter is widely used in the photovoltaic industry, PP, PE compatibilized blending, etc. industries due to its advantages of small relative density, easy processing, good mechanical properties, good chemical resistance and water resistance, etc.

[0003] Currently, 70% of UHMWPE produced in the global industry still uses supported Z-N catalysts. Such catalysts contain multiple active sites, and these active sites exhibit different reactivity, which easily produces polymers with a wide molecular weight distribution (about 5-20). The growing polymer chains are close to each other, increasing the possibility of chain entanglement. This chain entanglement and ultra-low branching degree (less than one hundred thousandth) make it difficult to use traditional processing techniques for processing. Therefore, it is still necessary to change the types of electron donors and supports of Z-N catalysts to further optimize their catalytic performance. For metallocene catalysts, under suitable conditions, few metallocene complexes can achieve ultra-high molecular weight polyethylene. In addition, a large amount of excess MAO activator is often required during the preparation of polyethylene, which undoubtedly increases the production cost. Therefore, reducing the use cost and simplifying the process have become the focus of research on such catalysts. Non-metallocene late transition catalysts have gradually become a research hotspot due to their low price, environmental friendliness, stability and ease of availability. Researchers can achieve precise control of polymer structure through the design and synthesis of ligands, and obtain UHMWPE with high molecular weight, narrow distribution, disentanglement and low branching. However, the following one or more principles should be combined in catalyst design: (a) the metal center should have high electrophilicity, (b) the chain transfer rate should be as low as possible, (c) the ligands around the metal must give the catalytic center a proper balance of electronic and steric effects to maximize the rate of ethylene insertion and inhibit the rate of chain transfer, (d) pressure and temperature also play an important role. Therefore, it is quite challenging to produce such high molecular weight polyethylene by repeated insertion of ethylene.

[0004] Polyolefin elastomer (POE) is a polymer produced by copolymerization of ethylene and α-olefin, which was first introduced to the market by Dow Chemical Company in 1994. Due to the technical barriers of catalysts, the lack of polymerization process, and the supply of raw materials α-olefin, China currently relies on imports for the products needed for consumption, so further research on POE is still needed.

[0005] In 2020, Professor Jian Zhongbao's research group designed an α-diimine catalyst with a double-layer space strategy, which can produce ultra-high molecular weight polyethylene by combining with methylaluminoxane activator. The molecular weight can reach 467 × 10 4 g·mol -1 (J.Catal.,2020,390,30-36,CN 111548285 A); In 2021, Professor Dai Shengyuo's research group used a double steric hindrance effect to prepare a more stable catalyst, which can produce ultra-high molecular weight polyethylene (M w =127.3g mol -1 , branching degree: 80-150 / 1000C) (Organometallics,2022,41,124-132,CN114349658 A); After that, the catalyst combined with the bulky diphenylmethyl substituent and the benzocycloalkyl group was also designed by the research group, which further improved the catalytic activity (10 7 g mol -1 h -1 ), and produced ultra-high molecular weight polyethylene (M w =185×10 4 g mol -1 ) with low branching degree (25-43 / 1000C), but also resulted in a high molecular weight distribution (Polym. Chem.,2023,14,183-190); In 2023, Professor Sun Wenhua's research group combined the bulky diphenylmethyl substituent with the flexible cycloalkyl substituent, and produced polyethylene that can reach ultra-high molecular weight (Molecules,2023,28,4852-4872,CN 116396338 A). The synergistic effect of the steric substituent and the electronic substituent improved the performance of the catalyst, and the introduction of three methoxy groups significantly improved the chain growth rate and promoted the synthesis of ultra-high molecular weight polyethylene (M w =126×10 4 g mol -1(Polymer, 2024, 293, 126690-126703); patent CN 103288985 A also discloses the copolymerization of ethylene and alpha-olefins, which can obtain high molecular weight elastic polymers; patent CN 115594785 A is a POE polymer with high 1-octene content that can be prepared with very high activity.

[0006] In summary, producing high-performance polyolefins to solve the problems of high cost and insufficient competitiveness in the domestic industry has become a solution, so it is urgent to develop a catalyst to produce functionalized high-end polyethylene. SUMMARY

[0007] In order to improve the activity of the catalyst, produce high-performance high-end polyolefins, and improve the molecular weight and insertion ratio of the copolymerization product of ethylene and polar monomers, the present application provides an alpha-diamine nickel complex, a synthesis method and application. The alpha-diamine nickel complex is a post-transition metal nickel catalyst combined with a series of electronic substituents and stereosubstituents.

[0008] To solve the above technical problems, the technical scheme provided by the present application is as follows:

[0009] The alpha-diamine nickel complex has a chemical structure shown in formula (I):

[0010]

[0011] wherein R 1 is one of benzhydryl, phenyl, 3,5-difluorophenyl, 3,5-dimethylphenyl, and 3,5-ditrifluoromethylphenyl, and R 2 is one of halogen, alkyl, and alkoxy;

[0012] Preferably, the alpha-diamine nickel complex of the chemical structure shown in formula (I) includes at least one of I1-I7:

[0013]

[0014] More preferably, the alpha-diamine nickel complex of the chemical structure shown in formula (I) is I2 and I7.

[0015] The present application provides a synthesis method of the alpha-diamine nickel complex having the chemical structure shown in formula (I), comprising the following steps:

[0016] (1) reacting the dibenzotetracene shown in formula (II) with the aniline compound shown in formula (III) under the catalysis of zinc dichloride at 130°C for 12-36h to obtain the alpha-diamine compound shown in formula (IV), and the reaction route is shown below:

[0017]

[0018] wherein R 1 is one of benzhydryl, phenyl, 3,5-difluorophenyl, 3,5-dimethylphenyl, 3,5-ditrifluoromethylphenyl, 3,5-di-tert-butylphenyl, R 2 is one of halogen, alkoxy;

[0019] (2) reacting the α-diimine compound of formula (IV) with (DME)NiBr2 at 0-45℃ for 1-50h to form the α-diimine nickel complex of formula (I);

[0020] In the synthesis method of the α-diimine nickel complex of formula (I) provided by the present application, the molar ratio of the compound of formula (II) to the aniline compound of formula (III) is 1:(2-3).

[0021] In the synthesis method of the α-diimine nickel complex of formula (I) provided by the present application, the α-diimine compound of formula (IV) is reacted with (DME)NiBr2 in an organic solvent, which is an organic solvent known to those skilled in the art, preferably a halogenated alkane, more preferably dichloromethane. The molar ratio of the α-diimine compound to (DME)NiBr2 is 1:(0.1-6), and in specific embodiments, the molar ratio of the α-diimine compound to (DME)NiBr2 is 1:(1-3). Preferably, the reaction is carried out at 0-38℃, and the reaction time is 12-24h.

[0022] The present application also provides the use of the α-diimine nickel complex of formula (I) in the synthesis of polyolefins, specifically, the use of the α-diimine nickel complex as a super-high-activity and high-thermal-stability catalyst to catalyze the polymerization of ethylene to prepare a super-high-molecular-weight polyethylene thermoplastic elastomer and a POE material.

[0023] In some embodiments of the present application, the use comprises contacting a compound containing a terminal olefin group with the α-diimine nickel complex of formula (I) and an alkyl aluminum reagent, and the compound containing a terminal olefin group undergoes a homopolymerization reaction. In this use, the homopolymerization reaction is carried out in an organic solvent, the amount of the α-diimine nickel complex used is 5-40μmol / L, the temperature of the homopolymerization reaction is 0-150℃, the pressure is 0.1-2.0MPa, and the reaction time is 0.05-3.00h.

[0024] More preferably, the concentration of the α-diimine nickel complex is 20μmol / L, the temperature of the homopolymerization reaction is 30℃, the pressure is 0.8MPa, and the reaction time is 10min, which can achieve the optimal catalytic effect.

[0025] In some embodiments provided by the application, the application comprises: contacting a terminal-alkenyl-containing compound, a polar monomer, an alpha-diimine nickel complex having the chemical structure shown in formula (I), and an alkyl aluminum reagent, the terminal-alkenyl-containing compound and the polar monomer undergo a copolymerization reaction; the polar monomer refers to an olefin containing a heteroatom, and includes at least one of methyl 10-undecylenate, methyl acrylate, vinyltrimethoxysilane, acrylate propyl, methyl norbornene, 1-octene, 6-chloro-1-hexene, 10-undecenol, etc. In the application, the copolymerization reaction temperature is 0-50°C, the copolymerization reaction pressure is 0.1-1 MPa, and the reaction time is 0.05-3.00 hours. The concentration of the alpha-diimine nickel complex is 200-400 μmol / L, and the monomer concentration is 0.1-3.0 M.

[0026] More preferably, 400 μmol / L of catalyst I7 is polymerized with 3.0 M of 1-octene at 30°C and 0.2 MPa for 30 min to prepare high-performance polyethylene-POE, which has a strain performance of up to 2300% and an elastic recovery rate of up to 71%.

[0027] Preferably, in the above application, the terminal-alkenyl-containing compound is an olefin, and more preferably ethylene, and the alkyl aluminum reagent includes one or more of MAO, MMAO, AlMe3, AlEtCl2, AlEt2Cl, AlEt3.

[0028] The above alpha-diimine nickel complex, on one hand, inhibits chain transfer by increasing steric hindrance to improve the thermal stability of the catalyst and the molecular weight of the polymer; on the other hand, the electronic substituent on the aniline enhances the activity of the catalyst. The alpha-diimine nickel complex maintains high catalytic activity in the copolymerization reaction of ethylene and various polar monomers.

[0029] Compared with the prior art, the application has the following advantages and beneficial effects:

[0030] The alpha-diimine nickel complex having the chemical structure shown in formula (I) provided by the application fully inhibits chain transfer due to the introduction of a rigid dibenzo barrel skeleton and a large steric hindrance aromatic group on the aniline. By adjusting the different electronic substituents on the para position of the aniline and the aromatic substituent, the activity of the catalyst is greatly enhanced, the catalyst can efficiently catalyze ethylene polymerization, the catalytic activity is improved, various high-end polyolefins such as ultrahigh molecular weight polyethylene and POE are produced, and the alpha-diimine nickel complex can effectively catalyze the copolymerization of ethylene and various polar monomers to produce polar functionalized polyethylene.

[0031] The catalytic activity of the alpha-diimine nickel complex with a reasonable ligand design in ethylene polymerization can reach 1.0×10 8 g·mol -1 ·h -1, 1 kg of catalyst can produce 2.54 kilotons of product, and still maintain a catalytic activity of 10 6 g·mol -1 ·h -1 at 120 °C, which is the heat resistance that most post-transition metal catalysts cannot achieve; the catalyst can also produce ultra-high molecular weight polyethylene (79-833 x 10 4 g·mol -1 ) that can reach commercial standards; at the same time, it has a lower degree of branching (15-41 / 1000C) and very excellent mechanical properties (stress: 2.5-43 MPa, strain: 170%-2280%); and when copolymerizing ethylene with various monomers, it also maintains good catalytic activity (up to 13.34 x 10 5 g·mol -1 ·h -1 ) and a higher insertion ratio (1-octene insertion rate up to 13.34%), producing POE polymers or polar functionalized polyolefins.

[0032] In olefin polymerization, I1-I7 utilizes the large steric hindrance of the dibenzo barrelene skeleton to shield the steric hindrance of the metal back; at the same time, the large steric space of the ortho aromatic substituent inhibits chain transfer, reduces the molecular weight distribution of the polymer, greatly increases the molecular weight of the polymer, and the ultra-high molecular weight polyethylene catalyzed by I2 is even as high as 833.3 x 10 4 g·mol -1 , before which catalysts capable of producing such high molecular weight polyethylene were extremely rare. With increasing temperature, the introduction of these large steric hindrance aromatic substituents greatly enhances the stability of the nickel complex; and I1 can still catalyze ethylene polymerization at 120 °C with a high activity of 7.32 x 10 6 g·mol -1 ·h -1 , which fully demonstrates the high thermal stability of such catalysts. I2, I3, I5, and I7 introduce electron-withdrawing groups at different positions on different benzene rings, greatly improving the activity of the catalyst. In addition, by adjusting the temperature, pressure, and other conditions of the polymerization reaction, the highest activity of the catalyst can reach 1.0 x 10 8 g·mol -1 ·h -1 (Application Example 14). 1 kg of catalyst can produce 2.54 kilotons of product. More interestingly, I1-3, I5 can all produce ultra-high molecular weight thermoplastic elastomers, among which the stress value of the ultra-high molecular weight thermoplastic elastomer prepared by I1 at 50 °C can reach 43 MPa, and the polyethylene prepared by I2 at 70 °C maintains an ultra-high molecular weight (833.3 x 10 4 g·mol -1) and good tensile properties (maximum strain up to 770%). By introducing different electronic groups at the ortho or para position of benzene, the elimination of β-H can be well inhibited, and the activity and molecular weight of the catalyst can be improved.

[0033] and I1-3, I7 catalysts can copolymerize with a variety of polar monomers to produce functional polyolefins. In addition, I7 can also copolymerize with 1-octene to prepare high-performance polyethylene-POE, which has a strain property of up to 2300% and an elastic recovery rate of up to 71%. Therefore, the α-diimine nickel complex provided by the present application has great potential in the field of olefin polymerization for synthesizing ultra-high molecular weight polyethylene, POE and other high-end polyolefins. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0035] Figure 1 The single crystal structure diagram of the α-diimine nickel complex I1 provided for the embodiment 8 of the present application.

[0036] Figure 2 The single crystal structure diagram of the α-diimine nickel complex I2 provided for the embodiment 9 of the present application.

[0037] Figure 3 The single crystal structure diagram of the α-diimine nickel complex I3 provided for the embodiment 10 of the present application.

[0038] Figure 4 The polyethylene tensile curve image prepared by the α-diimine nickel complex I1 provided for the application examples 1-5 of the present application.

[0039] Figure 5 The polyethylene tensile curve image prepared by the α-diimine nickel complex I2 provided for the reference example 9 of the present application.

[0040] Figure 6 The polyethylene tensile curve image prepared by the α-diimine nickel complex I3 provided for the embodiment 10 of the present application.

[0041] Figure 7 The POE tensile curve image prepared by the α-diimine nickel complex I7 provided for the application examples 47, 48 and 49 of the present application.

[0042] Figure 8 The POE elastic recovery image prepared by the α-diimine nickel complex I7 provided for the application example 47 of the present application.

[0043] Figure 9 POE elastomeric image prepared from the α-diimine nickel complex I7 provided in application example 48 of the present invention.

[0044] Figure 10 POE elastomeric image prepared from the α-diimine nickel complex I7 provided in application example 49 of the present invention. DETAILED DESCRIPTION

[0045] In order to make the objects, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be described below in connection with embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present invention.

[0046] In the present invention, the term "DME" represents dimethylether glycol; the term "terminal-alkenyl-containing compound" refers to small-molecule organic compounds with C=C double bond at the terminal, including alkenes, terminal-alkenyl-containing fatty acids, esters, and the like. In the α-diimine nickel complex, the "—" connected to Ni refers to a covalent bond or a coordination bond.

[0047] Unless otherwise specified, the process of homo- and co-polymerization is well known to those skilled in the art, and will not be described here in detail.

[0048] The following examples of the present invention show different aspects of the present invention. The data provided include the synthesis of ligands, the synthesis of metal complexes, polymerization operations, polymerization conditions, and polymerization products. All operations including reactions, preparations, and storage are carried out under dry inert atmosphere using standard Schlenk operations. The molecular weight and molecular weight distribution are determined by GPC. The determination is carried out on an Agilent PL-200 instrument using Agilent PLgel Olexis as the chromatographic column, with trichlorobenzene as the solvent. The correction of polyethylene is carried out by general calibration using Mark-Houwink parameters: K = 1.75 x 10 -2 cm 3 / g, R = 0.67 (polystyrene), K = 5.90 x 10 -2 cm 3 / g, R = 0.69 (polyethylene).

[0049] In the present invention, the preparation route of the α-diimine compound is shown as follows:

[0050]

[0051] Example 1

[0052] The present example provides a method for synthesizing an α-diimine compound IV1, comprising the following steps:

[0053] In a 50 mL Schlenk flask, add dibenzoannulene (469 mg, 2 mmol) of formula (II), 2-dibenzyl-4-methoxy-6-methyl aniline (1.47 g, 4.4 mmol), zinc dichloride (272 mg, 2 mmol), 5 mL glacial acetic acid, heat to 130°C reflux for 24 h. The reaction is complete, cool to room temperature, and the reaction system precipitates a yellow precipitate. Filter the yellow precipitate and wash with glacial acetic acid and diethyl ether, and the resulting solid is a zinc dichloride complex of IV1. Dissolve the resulting solid in 50 mL dichloromethane, add an aqueous solution of potassium oxalate (536 mg, 4 mmol) (10 ml) and stir for 12 h, extract the organic layer with dichloromethane (50 mL x 3), dry over anhydrous sodium sulfate, and remove the solvent under reduced pressure to obtain a yellow solid as a crude product. Recrystallize the crude product in a mixed solution of dichloromethane and methanol to obtain a yellow solid as pure α-diimine compound IV1, 1.48 g (92%). The experimental data of the compound are as follows: 1 H NMR (400 MHz, CDC13) δ = 7.24 - 7.16 (m, 10H, aryl-H), 7.11 - 7.04 (m, 10H, aryl-H), 6.94 (dd, J = 7.5, 2.0 Hz, 4H, aryl-H), 6.76 (d, J = 2.4 Hz, 2H, aryl-H), 6.69 (dd, J = 5.4, 3.2 Hz, 2H, aryl-H), 6.62 (d, J = 2.8 Hz, 2H, aryl-H), 6.31 (dd, J = 5.4, 3.2 Hz, 2H, aryl-H), 5.43 (s, 2H, CHPh2), 4.83 (s, 2H, CHDB), 3.77 (s, 6H, CH3), 1.90 (s, 6H, CH3) ppm. 13 C{ 1 H} NMR (101 MHz, CDC13) δ = 161.02 (C=N), 155.64, 144.46, 142.74, 140.64, 138.77, 137.70, 134.20, 129.48, 129.14, 128.43, 128.06, 127.15, 127.04, 126.80, 126.38, 125.95, 125.78, 124.32, 114.28, 113.54, 55.25 (OCH3), 51.30 (CHDB), 51.12 (CHPh2), 19.00 (CH3) ppm.

[0054] Example 2

[0055] The present example provides a method for synthesizing an α-diimine compound IV2, comprising the following steps:

[0056] In a 50 mL Schlenk flask, add dibenzoannulene (469 mg, 2 mmol) of formula (II), 2-dibenzyl-4-fluoro-6-methylaniline (1.28 g, 4.4 mmol), zinc dichloride (272 mg, 2 mmol), 5 mL glacial acetic acid, heat to 130 °C reflux for 24 h. The reaction is complete, cool to room temperature, the reaction system precipitates a yellow precipitate. Filter the yellow precipitate, wash with glacial acetic acid and diethyl ether, the resulting solid is a zinc dichloride complex of IV2. Dissolve the solid obtained above in 50 mL dichloromethane, add an aqueous solution of potassium oxalate (536 mg, 4 mmol) (10 ml) and stir for 12 h, extract the organic layer with dichloromethane (50 mL x 3), dry over anhydrous sodium sulfate, remove the solvent under reduced pressure to obtain a yellow solid as a crude product. Recrystallize the crude product in a mixed solution of dichloromethane and methanol to obtain a yellow solid as pure α-diimine compound IV2, 1.45 g (93%). The experimental data of the compound are as follows: 1 H NMR (400 MHz, CDC13) δ = 7.25 - 7.20 (m, 10H, aryl-H), 7.10 - 7.06 (m, 10H, aryl-H), 6.93 - 6.89 (m, 6H, aryl-H), 6.78 (d, J = 2.9 Hz, 1H, aryl-H), 6.76 (d, J = 2.8 Hz, 1H, aryl-H), 6.72 (dd, J = 5.4, 3.1 Hz, 2H, aryl-H), 6.32 (dd, J = 5.4, 3.3 Hz, 2H, aryl-H), 5.39 (s, 2H, 2CHPh2), 4.79 (s, 2H, CHDB), 1.89 (s, 6H, CH3) ppm. 13 C{1H}NMR (101 MHz, CDC13) δ = 160.89 (C=N), 159.01 (d, 1 J C-F = 242.2 Hz), 143.62, 142.60, 141.87, 138.11, 137.05, 134.33, 134.26, 129.08, 128.73, 128.31, 127.91, 127.34 (d, 3 J C-F = 7.8 Hz), 127.05 (d, 3 J C-F= 16.5 Hz), 126.36 125.94, 125.50, 124.09, 115.14, 114.92 114.83, 114.60, 51.02 (CHDB), 50.78 (CHPh2), 18.45 (CH3) ppm. 19 F NMR (376 MHz, CDC13) δ = -120.22 (t, J = 9.3 Hz) ppm.

[0057] Example 3

[0058] This example provides a method for synthesizing the a-diimine compound IV3, comprising the steps of:

[0059] In a 50 mL Schlenk bottle, add formula (II) (469 mg, 2 mmol), 2-diphenylmethyl-4-chloro-6-methylaniline (1.35 g, 4.4 mmol), zinc dichloride (272 mg, 2 mmol), 5 mL glacial acetic acid, heat to 130 °C reflux for 24 h. The reaction is completed, cooled to room temperature, the reaction system precipitates a yellow precipitate. Filter the yellow precipitate, wash with glacial acetic acid and diethyl ether, the resulting solid is a zinc dichloride complex of IV3. Dissolve the solid obtained above in 50 mL dichloromethane, add an aqueous solution of potassium oxalate (536 mg, 4 mmol) (10 ml) and stir for 12 h, extract the organic layer with dichloromethane (50 mL x 3), dry over anhydrous sodium sulfate, remove the solvent under reduced pressure to obtain a yellow solid as a crude product. Recrystallize the crude product in a mixture of dichloromethane and methanol to obtain a yellow solid as pure a-diimine compound IV3, 1.48 g (91%). The experimental data of this compound are: 1 H NMR (400 MHz, CDC13) δ = 7.24 - 7.18 (m, 12H, aryl-H), 7.08 - 7.06 (m, 10H, aryl-H), 7.01 (d, J = 2.3 Hz, 2H aryl-H), 6.89 (dd, J = 6.5, 2.8 Hz, 2H, aryl-H), 6.72 (dd, J = 5.4, 3.3 Hz, 4H, aryl-H), aryl-H), 6.31 (dd, J = 5.4, 3.3 Hz, 2H aryl-H), 5.35 (s, 2H, CHPh2), 4.75 (s, 2H, CHDB), 1.86 (s, 6H, CH3) ppm. 13 C{ 1H}NMR (101 MHz, CDC13) δ = 160.66 (C=N), 158.22, 145.22, 143.47, 141.70, 137.95, 136.88, 134.22, 129.09, 128.73, 128.35, 127.95, 127.34, 127.23, 127.06, 126.41, 126.00, 125.52, 124.12, 51.06 (CHDB), 50.71 (CHPh2), 18.19 (CH3) ppm.

[0060] Example 4

[0061] This example provides a method for synthesizing the α-diimine compound IV4, comprising the steps of:

[0062] In a 50 mL Schlenk bottle, add formula (II) (469 mg, 2 mmol), 3,5-dimethyl-[1,1']biphenyl-2-amine (0.87 g, 4.4 mmol), zinc dichloride (272 mg, 2 mmol), 5 mL glacial acetic acid, heat to 130 °C reflux for 24 h. After the reaction is completed, cool to room temperature, and the reaction system precipitates yellow precipitate. Filter the yellow precipitate, wash with glacial acetic acid and diethyl ether, and the resulting solid is a zinc dichloride complex of IV4. Dissolve the resulting solid in 50 mL dichloromethane, add an aqueous solution (10 ml) of potassium oxalate (536 mg, 4 mmol), stir for 12 h, extract the organic layer with dichloromethane (50 mL x 3), dry over anhydrous sodium sulfate, and remove the solvent under reduced pressure to obtain a yellow solid as a crude product. Recrystallize the crude product in a mixed solution of dichloromethane and methanol to obtain a yellow solid as pure α-diimine compound IV4, 1.12 g (95%). The experimental data of this compound are as follows: 1H NMR (600 MHz, CDC13) Isomer 1: δ = 7.53 - 7.51 (m, 4H aryl-H), 7.24 (s, 2H, aryl-H), 7.07 - 7.04 (m, 8H, aryl-H), 6.96 - 6.93 (m, 4H, aryl-H), 6.78 (td, J = 7.5, 1.2 Hz, 2H, aryl-H), 6.51 (d, J = 7.4 Hz, 2H, aryl-H), 4.62 (s, 2H, CH2B), 2.44 (s, 6H, aryl-CH3), 1.86 (s, 6H, aryl-CH3) ppm. Isomer 2: 7.41 - 7.39 (m, 1H, aryl-H), 7.16 (s, 0.5H, aryl-H), 7.12 (dd, J = 5.5, 3.2 Hz, 0.5H, aryl-H), 7.08 (s, 0.5H, aryl-H), 6.88 - 6.87 (m, 2H, aryl-H), 6.75 (dd, J = 5.5, 3.2 Hz, 0.5H, aryl-H), 6.53 (dd, J = 5.5, 3.2 Hz, 0.5H, aryl-H), 4.71 (s, 0.5H, CH2B), 2.42 (s, 6H, aryl-CH3), 1.80 (s, 6H, aryl-CH3) ppm. 13 C{ 1 H} NMR (151 MHz, CDC13) Isomer 1: δ = 158.45, 139.06, 137.14, 136.70, 133.32, 130.10, 129.55, 129.17, 128.25, 127.62 127.27, 126.83, 126.76, 126.35, 125.11, 123.79, 50.78, 20.96, 18.09 ppm. Isomer 2: 159.19 (C=N), 144.16, 139.29, 138.29, 136.25, 133.24, 130.22, 130.17, 128.93, 128.59, 129.73, 127.33, 127.13, 126.51, 126.26, 124.88, 124.55, 51.04 (CH2B), 20.89, 18.07 ppm.

[0063] Example 5

[0064] This example provides a method for the synthesis of the a-diimine compound IV5, comprising the steps of:

[0065] In a 50 mL Schlenk flask, add compound of formula (II) (469 mg, 2 mmol), 3',5'-difluoro-3,5-dimethyl-[1,1']biphenyl-2-amine (1.03 g, 4.4 mmol), zinc dichloride (272 mg, 2 mmol), 5 mL glacial acetic acid, heat to 130 °C and reflux for 24 h. Cool to room temperature, the reaction system precipitates yellow solid. Filter the yellow solid, wash with glacial acetic acid and diethyl ether, the obtained solid is zinc dichloride complex of IV5. Dissolve the obtained solid in 50 mL dichloromethane, add potassium oxalate (536 mg, 4 mmol) aqueous solution (10 ml) and stir for 12 h, extract the organic layer with dichloromethane (50 mL x 3), dry over anhydrous sodium sulfate, remove the solvent under reduced pressure to obtain a yellow solid as a crude product. Recrystallize the crude product in a mixture of dichloromethane and methanol to obtain a yellow solid as pure α-diimine compound IV5, 1.23 g (93 %). The experimental data of the compound are as follows: 1 H NMR (600 MHz, CDC13) δ = 7.17 (s, 2H, aryl-H), 7.12 (s, 2H, aryl-H), 7.04-7.01 (m, 6H, aryl-H), 6.96-6.92 (m, 4H, aryl-H), 6.64 (d, J = 7.3 Hz, 2H, aryl-H), 6.37 (tt, J = 8.9, 2.4 Hz, 2H, aryl-H), 4.62 (s, 2H, CH2B), 2.43 (s, 6H, aryl-CH3), 1.87 (s, 6H, aryl-CH3) ppm. 13 C{ 1 H} NMR (151 MHz, CDC13) δ = 162.51 (dd, J C-F = 246.7, 13.2 Hz), 158.87 (C=N), 144.11, 142.47 (t, J C-F = 9.8 Hz), 136.53, 133.81, 131.33, 127.87, 127.82, 127.50, 126.94, 124.90, 124.29, 112.05 (dd, J = 20.9, 5.4 Hz), 101.47 (t, J C-F = 25.4 Hz), 50.86 (CH2B), 20.89, 17.91 ppm. 19 F{ 1 H} NMR (565 MHz, CDC13) δ = -110.98 ppm.

[0066] Example 6

[0067] This example provides a method for synthesizing α-diimine compound IV6, comprising the steps of:

[0068] In a 50 mL Schlenk flask, 1 mL of Schlenk flask, add formula (II) (469 mg, 2 mmol), 3,3',5,5'-tetramethyl-[1,1']biphenyl-2-amine (0.99 g, 4.4 mmol), zinc dichloride (272 mg, 2 mmol), 5 mL glacial acetic acid, heated to 130 °C reflux for 24 h. The reaction is completed, cooled to room temperature, the reaction system precipitated yellow precipitate. Filter the yellow precipitate, washed with glacial acetic acid and diethyl ether, the resulting solid is a zinc dichloride complex of IV6. The above-mentioned solid is dissolved in 50 mL dichloromethane, add potassium oxalate (536 mg, 4 mmol) aqueous solution (10 ml) stirring for 12 h, using dichloromethane (50 mL x 3) extraction of organic layer, anhydrous sodium sulfate drying, removal of solvent by reduced pressure distillation after the yellow solid as crude product. The crude product in a mixture of dichloromethane and methanol recrystallization, namely the yellow solid as pure α-diimine compound IV6, 1.22 g (94 %). The experimental data of the compound: 1 H NMR (400 MHz, CDC13): isomer 1: δ = 7.14 (d, J = 1.4 Hz, 1H, aryl-H), 7.44 (dd, J = 2.0, 1.3 Hz, 2H, aryl-H), 7.31 (dd, J = 2.0, 1.3 Hz, 2H, aryl-H), 7.19 (d, J = 1.6 Hz, 1H, aryl-H), 7.07-7.16 (m, 10H, aryl-H), 6.83-7.04 (m, 2H, aryl-H), 4.22 (s, 2H, CH2B), 2.32 (s, 12H, CH3), 2.27 (s, 6H, CH3), 2.22 (s, 6H, CH3) ppm. 13 C{ 1 H} NMR (101 MHz, CDC13): δ = 150.7, 141.3, 138.3, 137.4, 137.1, 130.0, 129.6, 128.9, 128.5, 128.0, 126.6, 126.2, 123.9, 116.8, 51.8, 21.3, 21.6, 18.6 ppm.

[0069] Example 7

[0070] This example provides a method for synthesizing α-diimine compound IV7, comprising the steps of:

[0071] In a 50 mL Schlenk flask, add formula (II) (469 mg, 2 mmol), 3',5'-distrifluoromethyl-3,5-dimethyl-[1,1']biphenyl-2-amine (1.47 g, 4.4 mmol), zinc dichloride (272 mg, 2 mmol), 5 mL glacial acetic acid, heat to 130 °C reflux for 24 h. The reaction is finished, cool to room temperature, the reaction system precipitate yellow. Filter the yellow precipitate, using glacial acetic acid and ether wash, the resulting solid is a zinc dichloride complex of IV7. The above-mentioned solid is dissolved in 50 mL dichloromethane, add potassium oxalate (536 mg, 4 mmol) aqueous solution (10 ml) stirring for 12 h, using dichloromethane (50 mL x 3) extraction of organic layer, anhydrous sodium sulfate drying, remove the solvent by reduced pressure distillation after the yellow solid as crude product. The crude product in a mixture of dichloromethane and methanol recrystallization, get yellow solid as pure α-diimine compound IV7, 1.67 g (96 %). The experimental data of the compound: 1 H NMR (600 MHz, CDC13) δ = 7.83 (s, 4H, aryl-H)), 7.54 (s, 2H, aryl-H), 7.16 (s, 1H, aryl-H)), 7.08 (s, 1H, aryl-H)), 7.05 - 6.99 (m, 4H, aryl-H)), 6.89 (t, J = 7.4 Hz, 2H, aryl-H)), 6.63 (d, J = 7.4 Hz, 2H, aryl-H), 4.70 (s, 2H, CH2B), 2.44 (s, 6H, aryl-CH3), 1.75 (s, 6H, aryl-CH3) ppm. 13 C{ 1 H} NMR (151 MHz, CDC13) δ = 160.36, 143.93, 142.02, 136.88 (d, J C-F = 10.2 Hz), 134.21, 131.87, 131.14 (q, J C-F = 32.9 Hz), 129.02, 128.89, 127.82, 127.64, 127.62, 127.35, 124.91, 124.44, 123.24 (q, J C-F = 273.2 Hz) 120.45 (q, J C-F = 4.1 Hz), 51.13, 20.78, 18.00 ppm. 19 F{ 1 H} NMR (565 MHz, CDC13) δ = -62.53 ppm.

[0072] Example 8

[0073] This example provides a method for synthesizing an α-diimine nickel complex I1, comprising the following steps:

[0074] In an argon atmosphere glove box, a 50 mL round bottom flask was charged with the α-diimine compound IV1(0.80 g, 1.00 mmol) prepared in Example 1, (DME)NiBr2(0.31 g, 1.00 mmol), 10 mL of anhydrous dichloromethane, and stirred at room temperature for 24 h. After the reaction was completed, the reaction system was filtered using a fritted funnel, and the solvent was removed under vacuum. Reddish-brown solid was obtained by recrystallization in dichloromethane and n-hexane solution, which was complex I1, 0.98 g (95%). Experimental data of the α-diimine nickel complex I1: ESI-MS (m / z): [M-Br] + calcd for C 58 H 48 BrN2NiO2 + , 941.2253.

[0075] Example 9

[0076] This example provides a method for synthesizing an α-diimine nickel complex I2, comprising the following steps:

[0077] In an argon atmosphere glove box, a 50 mL round bottom flask was charged with the α-diimine compound IV2(0.78 g, 1.00 mmol) prepared in Example 1, (DME)NiBr2(0.31 g, 1.00 mmol), 10 mL of anhydrous dichloromethane, and stirred at room temperature for 24 h. After the reaction was completed, the reaction system was filtered using a fritted funnel, and the solvent was removed under vacuum. Reddish-brown solid was obtained by recrystallization in dichloromethane and n-hexane solution, which was complex I2, 1.09 g (93%). Experimental data of the α-diimine nickel complex I2: ESI-MS (m / z): [M-Br] + calcd for C 56 H 42 BrN2NiF2 + , 917.1853.

[0078] Example 10

[0079] This example provides a method for synthesizing an α-diimine nickel complex I3, comprising the following steps:

[0080] In an argon atmosphere glove box, a 50 mL round bottom flask was charged with the α-diimine compound IV3(0.81 g, 1.00 mmol) prepared in Example 1, (DME)NiBr2(0.31 g, 1.00 mmol), anhydrous dichloromethane 10 mL, stirred at room temperature for 24 h. After the reaction was completed, the reaction system was filtered using a fritted funnel, and the solvent was removed in vacuo. Recrystallization in dichloromethane and n-hexane solution gave a red-brown solid, which was the complex I3, 0.98 g (95%). Experimental data of the α-diimine nickel complex I3: ESI-MS (m / z): [M-Br] + calcd for C 56 H 42 BrN2NiCl2 + , 949.1262.

[0081] Example 11

[0082] This example provides a method for synthesizing an α-diimine nickel complex I4, comprising the following steps:

[0083] In an argon atmosphere glove box, a 50 mL round bottom flask was charged with the α-diimine compound IV3(0.81 g, 1.00 mmol) prepared in Example 1, (DME)NiBr2(0.31 g, 1.00 mmol), anhydrous dichloromethane 10 mL, stirred at room temperature for 24 h. After the reaction was completed, the reaction system was filtered using a fritted funnel, and the solvent was removed in vacuo. Recrystallization in dichloromethane and n-hexane solution gave a red-brown solid, which was the complex I3, 0.98 g (95%). Experimental data of the α-diimine nickel complex I3: ESI-MS (m / z): [M-Br] + calcd for C 44 H 36 BrN2Ni + , 729.1415.

[0084] Example 12

[0085] This example provides a method for synthesizing an α-diimine nickel complex I5, comprising the following steps:

[0086] In an argon atmosphere glove box, a 50 mL round bottom flask was charged with the α-diimine compound IV5 (0.66 g, 1.00 mmol) prepared in Example 1, (DME)NiBr2(0.31 g, 1.00 mmol), anhydrous dichloromethane 10 mL, stirred at room temperature for 24 h. After the reaction was completed, the reaction system was filtered using a fritted funnel, and the solvent was removed in vacuo. Recrystallization in dichloromethane and n-hexane solution gave a red-brown solid, which was the complex I5, 0.82 g (93 %). Experimental data of the α-diimine nickel complex I5: ESI-MS (m / z): [M-Br] + calcd for C 44 H 32 BrF4N2N i + , 801.1038.

[0087] Example 13

[0088] This example provides a method for synthesizing an α-diimine nickel complex I6, comprising the following steps:

[0089] In an argon atmosphere glove box, a 50 mL round bottom flask was charged with the α-diimine compound IV5 (0.66 g, 1.00 mmol) prepared in Example 1, (DME)NiBr2(0.31 g, 1.00 mmol), anhydrous dichloromethane 10 mL, stirred at room temperature for 24 h. After the reaction was completed, the reaction system was filtered using a fritted funnel, and the solvent was removed in vacuo. Recrystallization in dichloromethane and n-hexane solution gave a red-brown solid, which was the complex I5, 0.82 g (93 %). Experimental data of the α-diimine nickel complex I5: ESI-MS (m / z): [M-Br] + calcd for C 48 H 44 BrN2Ni + , 785.2041.

[0090] Example 14

[0091] This example provides a method for synthesizing an α-diimine nickel complex I7, comprising the following steps:

[0092] In an argon atmosphere glove box, a 50 mL round bottom flask was charged with the α-diimine compound IV7 (0.86 g, 1.00 mmol) prepared in Example 1, (DME)NiBr2(0.31 g, 1.00 mmol), anhydrous dichloromethane 10 mL, stirred at room temperature for 24 h. After the reaction was completed, the reaction system was filtered using a sand core funnel, and the solvent was removed under vacuum. Recrystallization in dichloromethane and n-hexane solution gave a brownish solid, which was the complex I7, 0.94 g (90%). Experimental data of the α-diimine nickel complex I7: ESI-MS (m / z): [M-Br] + calcd for C 48 H 32 BrF 12 N2Ni + , 1001.0911.

[0093] Examples 1-62 show that the α-diimine nickel complexes with different electronic properties and steric substituents exhibit special catalytic characteristics in the homopolymerization of ethylene and the copolymerization of ethylene and polar monomers: in a certain pressure range, the α-diimine nickel complexes realize the high-activity catalysis of ethylene polymerization to obtain high-performance polyolefin materials: polyolefin elastomers with narrow molecular weight distribution, low branching degree, ultrahigh molecular weight, and polarity.

[0094] Example 1

[0095] Under anhydrous and anaerobic conditions in a glove box, 100 mL of a thick-walled quartz dish was charged with anhydrous toluene (48 mL) and then placed in an intelligent olefin polymerization device; the reaction kettle was vacuumed and then saturated with ethylene, and AlEt2Cl (0.6 mL, 1M in toluene) was added; after preheating and stirring at 30°C, a dichloromethane (2 mL) solution of the α-diimine nickel complex I1 (1 μmol) was added, and the ethylene pressure was adjusted to 0.8 MPa, and the reaction was stirred for 10 min. After the reaction was completed, the reaction was quenched with an ethanol solution containing 5% hydrochloric acid. The polymer was precipitated, filtered, washed, and dried under vacuum at 50°C to constant weight to obtain the polymerization product. The specific experimental results are shown in Table 1.

[0096] Example 2

[0097] The experimental process was the same as that of Example 1, except that the reaction temperature was changed from 30°C to 50°C. The experimental results are shown in Table 1.

[0098] Example 3

[0099] The experimental process was the same as that of Example 1, except that the reaction temperature was changed from 30°C to 70°C. The experimental results are shown in Table 1.

[0100] Example 4

[0101] The experimental procedure is the same as in Application Example 1, except that the reaction temperature is changed from 30°C to 90°C. The experimental results are shown in Table 1.

[0102] Application Example 5

[0103] The experimental procedure is the same as in Application Example 1, except that the reaction temperature is changed from 30°C to 120°C. The experimental results are shown in Table 1.

[0104] Application Example 6

[0105] Table 1

[0106]

[0107] In Application Examples 1-6, under the conditions of a pressure of 0.8 MPa and a reaction time of 10 min, the electron-donating methoxy group enhances the linkage of the C=N bond, increases the electron cloud density of the metal center, and cooperates with the bulky benzhydryl substituent and the rigid diphenylene barrel skeleton to affect the chain walking and chain transfer process, so that the catalyst has less temperature influence, is still active even at 140°C, and exhibits high thermal stability. The molecular weight increases first and then decreases with increasing temperature, and the molecular weight distribution and the degree of branching both increase, which is mainly due to the chain transfer and chain walking of the diimine catalyst at high temperature.

[0108] Application Example 7

[0109] Under anhydrous and anaerobic conditions in a glove box, 100 mL of a thick-walled quartz dish was added with anhydrous toluene (48 mL) and then placed in an intelligent olefin polymerization device; the reaction kettle was vacuumed and then saturated with ethylene, and AlEt2Cl (0.6 mL, 1M in toluene) was added; after preheating and stirring at 90°C, a dichloromethane (2 mL) solution of the α-diimine nickel complex II (1 μmol) was added, the ethylene pressure was adjusted to 0.8 MPa, and stirring was performed for 20 min. After the reaction was completed, the reaction was quenched with a 5% hydrochloric acid ethanol solution. The polymer was precipitated, filtered, washed, and dried at 50°C under vacuum to constant weight to obtain a polymerization product. The specific experimental results are shown in Table 2.

[0110] Application Example 8

[0111] The experimental procedure is the same as in Application Example 7, except that the reaction time is changed from 20 min to 30 min. The experimental results are shown in Table 2.

[0112] Application Example 9

[0113] The experimental procedure is the same as in Application Example 7, except that the reaction time is changed from 20 min to 100 min. The experimental results are shown in Table 2.

[0114] Table 2

[0115]

[0116] Examples 4, 7-9 show the catalytic performance of catalyst I1 at different reaction times at a temperature of 90°C and a pressure of 0.8 MPa. Due to the high thermal stability of I1, the catalyst has a high activity at 90°C that cannot be achieved by other catalysts. Although the catalytic activity of I1 decreases slightly when the reaction time is extended at a high temperature of 90°C, it still remains at a high activity of 10 6 g·mol -1 ·h -1 , and the molecular weight of the product is hardly affected when the reaction time is extended at a high temperature.

[0117] Example 10

[0118] In an anhydrous and anaerobic glove box, 100 mL of thick-walled quartz dish was added with anhydrous toluene (48 mL) and then placed in an intelligent olefin polymerization device; the reaction kettle was vacuumed and then saturated with ethylene, and then AlEt2Cl (0.6 mL, 1M in toluene) was added; after preheating and stirring at 30°C, a solution of α-diimine nickel complex I2 (1 μmol) in dichloromethane (2 mL) was added, and the ethylene pressure was adjusted to 0.8 MPa, and the reaction was stirred for 10 min. After the reaction was completed, the reaction was quenched with an ethanol solution containing 5% hydrochloric acid. The polymer was precipitated, filtered, washed, and then dried at 50°C under vacuum to a constant weight to obtain a polymerization product. The specific experimental results are shown in Table 3.

[0119] Example 11

[0120] The experimental process was the same as that of Example 10, except that the reaction temperature was changed from 30°C to 50°C. The experimental results are shown in Table 3.

[0121] Example 12

[0122] The experimental process was the same as that of Example 10, except that the reaction temperature was changed from 30°C to 70°C. The experimental results are shown in Table 3.

[0123] Example 13

[0124] The experimental process was the same as that of Example 10, except that the reaction temperature was changed from 30°C to 90°C. The experimental results are shown in Table 3.

[0125] Table 3

[0126]

[0127] Examples 10-13, pressure 0.8 MPa, reaction time 10 min, I2 catalyst is affected by the para-position F substituent to show high activity at low temperature, and the activity decreases slightly at high temperature, and the molecular weight shows a trend of first increasing and then decreasing with temperature, because the chain transfer rate increases after the temperature rises, resulting in a decrease in molecular weight.

[0128] Example 14

[0129] Under anhydrous and anaerobic conditions in a glove box, 100 mL of thick-walled quartz dish was added with anhydrous toluene (48 mL) and then placed in an intelligent olefin polymerization device; the reaction kettle was vacuumed and then saturated with ethylene, and AlEt2Cl (0.6 mL, 1M in toluene) was added; after preheating and stirring at 30°C, a dichloromethane (2 mL) solution of α-diimine nickel complex I2 (0.25 μmol) was added, and the ethylene pressure was adjusted to 2.0 MPa, and the stirring reaction was carried out for 10 min. After the reaction was completed, the reaction was quenched with a 5% hydrochloric acid ethanol solution. The polymer was precipitated, filtered, washed, and vacuum dried at 50°C to constant weight to obtain a polymerization product. The specific experimental results are shown in Table 4.

[0130] Table 4

[0131]

[0132] By adjusting the temperature, pressure and catalyst dosage of the polymerization reaction, the activity of I2 catalyst is the highest at 30°C, in order to further explore its reaction activity, the ethylene pressure is appropriately increased to 2.0 MPa; in order to avoid too much polymer produced in the reaction to pollute and damage the reaction kettle, the amount of catalyst is appropriately reduced, and surprisingly, the activity of the catalyst can reach 1.0 x 10 8 g·mol -1 ·h -1 , and currently very few diimine catalysts can achieve such high activity.

[0133] Example 15

[0134] Under anhydrous and anaerobic conditions in a glove box, 100 mL of thick-walled quartz dish was added with anhydrous toluene (48 mL) and then placed in an intelligent olefin polymerization device; the reaction kettle was vacuumed and then saturated with ethylene, and AlEt2Cl (0.6 mL, 1M in toluene) was added; after preheating and stirring at 30°C, a dichloromethane (2 mL) solution of α-diimine nickel complex I3 (1 μmol) was added, and the ethylene pressure was adjusted to 0.8 MPa, and the stirring reaction was carried out for 10 min. After the reaction was completed, the reaction was quenched with a 5% hydrochloric acid ethanol solution. The polymer was precipitated, filtered, washed, and vacuum dried at 50°C to constant weight to obtain a polymerization product. The specific experimental results are shown in Table 5.

[0135] Application Example 16

[0136] The experimental procedure was the same as that of Application Example 15, except that the reaction temperature was changed from 30°C to 50°C. The experimental results are shown in Table 5.

[0137] Application Example 17

[0138] The experimental procedure was the same as that of Application Example 15, except that the reaction temperature was changed from 30°C to 70°C. The experimental results are shown in Table 5.

[0139] Application Example 18

[0140] The experimental procedure was the same as that of Application Example 15, except that the reaction temperature was changed from 30°C to 90°C. The experimental results are shown in Table 5.

[0141] Table 5

[0142]

[0143] Application Examples 15-18 show the catalytic performance of I3 catalyst at different reaction temperatures under a pressure of 0.8 MPa and a reaction time of 10 min. The influence of the para-position Cl substituent is high activity at low temperature, and slightly decreased activity at high temperature. The molecular weight shows a trend of first increasing and then decreasing with temperature, because the chain transfer rate increases at high temperature, resulting in a decrease in molecular weight.

[0144] Application Example 19

[0145] Under anhydrous and anaerobic conditions in a glove box, 100 mL of thick-walled quartz dish was added with anhydrous toluene (48 mL) and then placed in an intelligent olefin polymerization device; the reaction kettle was vacuumed and then saturated with ethylene, and AlEt2Cl (0.6 mL, 1 M in toluene) was added; after preheating and stirring at 30°C, a dichloromethane (2 mL) solution of α-diimine nickel complex I4 (1 μmol) was added, and the ethylene pressure was adjusted to 0.8 MPa, and the stirring reaction was carried out for 10 min. After the reaction was completed, the reaction was quenched with a 5% hydrochloric acid ethanol solution. The polymer was precipitated, filtered, washed, and dried at 50°C under vacuum to constant weight to obtain the polymerization product. The specific experimental results are shown in Table 6.

[0146] Application Example 20

[0147] The experimental procedure was the same as that of Application Example 19, except that the reaction temperature was changed from 30°C to 50°C. The experimental results are shown in Table 6.

[0148] Application Example 21

[0149] The experimental procedure was the same as that of Application Example 19, except that the reaction temperature was changed from 30°C to 70°C. The experimental results are shown in Table 6.

[0150] Example 22

[0151] The experimental procedure was the same as that of Example 19, except that the reaction temperature was changed from 30 °C to 90 °C. The experimental results are shown in Table 6.

[0152] Table 6

[0153]

[0154] Examples 19-22 show the catalytic performance of catalyst I4 at different temperatures under a pressure of 0.8 MPa and a reaction time of 10 min. Compared with catalysts I1-I3, the steric hindrance of the substituents of catalyst I4 is reduced, the chain transfer and chain walking rates are increased, the molecular weight is reduced, and the degree of branching is increased. Catalyst I4 exhibits high activity at low temperatures, and the activity slightly decreases at high temperatures. The molecular weight exhibits a trend of first increasing and then decreasing with temperature, because the chain transfer rate increases at high temperatures, resulting in a decrease in the molecular weight.

[0155] Example 23

[0156] Under anhydrous and anaerobic conditions in a glove box, 100 mL of a thick-walled quartz dish was charged with anhydrous toluene (48 mL) and then placed in an intelligent olefin polymerization device; the reaction kettle was vacuumed and then saturated with ethylene, and AlEt2Cl (0.6 mL, 1 M in toluene) was added; after preheating and stirring at 30 °C, a dichloromethane (2 mL) solution of α-diimine nickel complex I5 (1 μmol) was added, and the ethylene pressure was adjusted to 0.8 MPa, and the stirring was continued for 10 min. After the reaction was completed, the reaction was quenched with an ethanol solution containing 5% hydrochloric acid. The polymer was precipitated, filtered, washed, and dried at 50 °C under vacuum to constant weight to obtain a polymerization product. The specific experimental results are shown in Table 7.

[0157] Example 24

[0158] The experimental procedure was the same as that of Example 23, except that the reaction temperature was changed from 30 °C to 50 °C. The experimental results are shown in Table 7.

[0159] Example 25

[0160] The experimental procedure was the same as that of Example 23, except that the reaction temperature was changed from 30 °C to 70 °C. The experimental results are shown in Table 7.

[0161] Example 26

[0162] The experimental procedure was the same as that of Example 23, except that the reaction temperature was changed from 30 °C to 90 °C. The experimental results are shown in Table 7.

[0163] Table 7

[0164]

[0165] Examples 23-26 show the catalytic performance of I5 catalyst at different temperatures under the pressure of 0.8 MPa and the reaction time of 10 min. Compared with I4, the substituent of I5 catalyst is 3,5-difluorophenyl, and the interaction between F and β-H on the polymer leads to a slight increase in molecular weight. I5 shows high activity at low temperature, and the activity decreases slightly at high temperature, and the molecular weight shows a decreasing trend with temperature, because the electron-withdrawing F group is easily affected by temperature, leading to an increase in chain transfer rate and a decrease in molecular weight.

[0166] Example 27

[0167] Under anhydrous and anaerobic conditions in a glove box, 100 mL of thick-walled quartz dish was added with anhydrous toluene (48 mL) and then placed in an intelligent olefin polymerization device; the reaction kettle was vacuumed and then saturated with ethylene, and then AlEt2Cl (0.6 mL, 1M in toluene) was added; after preheating and stirring at 30°C, a dichloromethane (2 mL) solution of α-diimine nickel complex I6 (1 μmol) was added, and the ethylene pressure was adjusted to 0.8 MPa, and the stirring reaction was carried out for 10 min. After the reaction was completed, the reaction was quenched with a 5% hydrochloric acid ethanol solution. The polymer was precipitated, filtered, washed, and dried at 50°C under vacuum to constant weight to obtain the polymerization product. The specific experimental results are shown in Table 8.

[0168] Example 28

[0169] The experimental process is the same as that of Example 27, except that the reaction temperature is changed from 30°C to 50°C. The experimental results are shown in Table 8.

[0170] Example 29

[0171] The experimental process is the same as that of Example 27, except that the reaction temperature is changed from 30°C to 70°C. The experimental results are shown in Table 8.

[0172] Example 30

[0173] The experimental process is the same as that of Example 27, except that the reaction temperature is changed from 30°C to 90°C. The experimental results are shown in Table 8.

[0174] Table 8

[0175]

[0176] Examples 27-30 show the catalytic performance of I6 catalyst at different temperatures under the pressure of 0.8 MPa and the reaction time of 10 min. Compared with I4, the substituent of I6 catalyst is 3,5-dimethylphenyl, and the introduction of two methyl groups increases the steric hindrance, resulting in a slight increase in molecular weight. I6 shows high activity at low temperature, and the activity slightly decreases at high temperature, and the molecular weight shows a decreasing trend with temperature, because the chain transfer rate increases at high temperature, and the molecular weight decreases.

[0177] Example 31

[0178] Under anhydrous and anaerobic conditions in a glove box, 100 mL of thick-walled quartz dish was added with anhydrous toluene (48 mL) and then placed in an intelligent olefin polymerization device; the reaction kettle was vacuumed and then saturated with ethylene, and then AlEt2Cl (0.6 mL, 1M in toluene) was added; after preheating and stirring at 30°C, a dichloromethane (2 mL) solution of α-diimine nickel complex I7 (1 μmol) was added, and the ethylene pressure was adjusted to 0.8 MPa, and the stirring reaction was carried out for 10 min. After the reaction was completed, the reaction was quenched with 5% hydrochloric acid in ethanol solution. The polymer was precipitated, filtered, washed, and dried at 50°C under vacuum to constant weight to obtain the polymerization product. The specific experimental results are shown in Table 9.

[0179] Example 32

[0180] The experimental process is the same as that of Example 31, except that the reaction temperature is changed from 30°C to 50°C. The experimental results are shown in Table 9.

[0181] Example 33

[0182] The experimental process is the same as that of Example 31, except that the reaction temperature is changed from 30°C to 70°C. The experimental results are shown in Table 9.

[0183] Example 34

[0184] The experimental process is the same as that of Example 31, except that the reaction temperature is changed from 30°C to 90°C. The experimental results are shown in Table 9.

[0185] Table 9

[0186]

[0187]

[0188] Examples 31-34 show the catalytic performance of I7 catalyst at different temperatures under the pressure of 0.8 MPa and the reaction time of 10 min. The substituent group of I7 catalyst is 3,5-di(trifluoromethyl)phenyl, and the trifluoromethyl group is a strong electron-withdrawing substituent group. I7 exhibits high activity at low temperature, and the activity slightly decreases at high temperature. The molecular weight shows a decreasing trend with temperature, because the chain transfer rate increases at high temperature, and the molecular weight decreases.

[0189] The above 34 examples are ethylene homopolymerization.

[0190] Among the existing α-diimine catalysts capable of producing ultrahigh molecular weight, J. Catal., 2020, 390, 30-36, CN111548285A discloses an α-diimine catalyst with a double-layer space strategy, which can prepare ultrahigh molecular weight polyethylene by combining with methylaluminoxane activator, and the molecular weight can reach 467×10 4 g mol -1 ; Organometallics, 2022, 41, 124-132, CN114349658A utilizes the double steric hindrance effect to prepare a catalyst with higher stability, which can obtain ultrahigh branched polyethylene (M w =127.3 g mol -1 , branching degree: 80-150 / 1000C); Polym. Chem., 2023, 14, 183-190, a catalyst combining large steric hindered benzhydryl substituent and benzocycloalkyl is also designed by the research group, which further improves the catalytic activity (10 7 g mol -1 h -1 ), and prepares ultrahigh molecular weight polyethylene (M w =185×10 4 g mol -1 ) with low branching degree (25-43 / 1000C), but also leads to a higher molecular weight distribution; Polymer, 2024, 293, 126690-126703, synergistic effect of steric substituent and electronic substituent improves the performance of the catalyst, the introduction of three methoxy groups significantly improves the chain growth rate and promotes the synthesis of ultrahigh molecular weight polyethylene (M w =126×10 4 g mol -1 ).

[0191] In comparison with the above-mentioned catalysts, I1-I7 all exhibit ultrahigh activity performance in ethylene homopolymerization (at 30-90℃, activity≥10 7 g mol -1 h -1It possesses excellent high-temperature resistance (maintaining high activity even at 120℃), a level of heat resistance unmatched by the aforementioned catalysts, and can produce ultra-high molecular weight polyethylene (79~833×10⁻⁶). 4 g·mol -1 ), and the molecular weight distribution is narrow. It exhibits a low degree of branching (15–41 / 1000°C). Therefore, even under harsh high-temperature conditions, it can still achieve catalytic performance that the aforementioned catalysts cannot.

[0192] Application Example 35

[0193] Under anhydrous and oxygen-free conditions in a glove box, anhydrous toluene (20 mL) and AlEt2Cl (3 mL, 1 M in toluene) were added sequentially to a 350 mL thick-walled pressure-resistant bottle. The pressure-resistant bottle was removed from the glove box and connected to an ethylene gas line. After evacuation, ethylene was introduced until saturation. The mixture was preheated at 0.4 MPa and 30 °C with stirring for 10 min. Then, methyl 10-undecenoate (0.50 M) and a 2 mL solution of dichloromethane containing 5 μmol of α-diimide nickel complex I1 were added, and the reaction was stirred for 30 min. The reaction was terminated with ethanol containing 5% hydrochloric acid. After precipitation, filtration, and washing, the polymer was dried under vacuum at 50 °C to constant weight to obtain the polymer product. Specific experimental results are shown in Table 10.

[0194] Application Example 36

[0195] The experimental procedure was the same as in Application Example 35, except that catalyst I1 was replaced with I2. The experimental results are shown in Table 10.

[0196] Application Example 37

[0197] The experimental procedure was the same as in Application Example 35, except that catalyst I1 was replaced with I3. The experimental results are shown in Table 10.

[0198] Table 11

[0199]

[0200] Application Example 38

[0201] Into a 350 mL thick-walled pressure bottle, anhydrous toluene (20 mL) and AIEt2Cl (3 mL, 1 M in toluene) were added successively under anhydrous and anaerobic conditions in a glove box. The pressure bottle was taken out of the glove box and connected to an ethylene gas line. After vacuuming, ethylene was introduced until saturation. After preheating and stirring for 10 min at 0.4 MPa and 30°C, 6-chloro-l-hexene (0.50 M) and a dichloromethane (2 mL) solution of the α-diimine nickel complex II (5 μmol) were added. The reaction was stirred for 30 min. After the reaction was completed, the reaction was terminated with 5% hydrochloric acid in ethanol. The polymer was precipitated, filtered, washed, and dried at 50°C under vacuum to constant weight to obtain a polymerization product. The experimental results are shown in Table 12.

[0202] Example 39

[0203] The experimental procedure was the same as in Example 38, except that the catalyst II was replaced by I2. The experimental results are shown in Table 11.

[0204] Example 40

[0205] The experimental procedure was the same as in Example 38, except that the catalyst II was replaced by I3. The experimental results are shown in Table 11.

[0206] Table 11

[0207]

[0208] Example 41

[0209] Into a 350 mL thick-walled pressure bottle, anhydrous toluene (20 mL) and AIEt2Cl (3 mL, 1 M in toluene) were added successively under anhydrous and anaerobic conditions in a glove box. The pressure bottle was taken out of the glove box and connected to an ethylene gas line. After vacuuming, ethylene was introduced until saturation. After preheating and stirring for 10 min at 0.4 MPa and 30°C, vinyltrimethoxysilane (0.50 M) and a dichloromethane (2 mL) solution of the α-diimine nickel complex II (5 μmol) were added. The reaction was stirred for 30 min. After the reaction was completed, the reaction was terminated with 5% hydrochloric acid in ethanol. The polymer was precipitated, filtered, washed, and dried at 50°C under vacuum to constant weight to obtain a polymerization product. The experimental results are shown in Table 12.

[0210] Example 42

[0211] The experimental procedure was the same as in Example 41, except that the catalyst II was replaced by I2. The experimental results are shown in Table 12.

[0212] Example 43

[0213] The experimental procedure was the same as in Example 41, except that the catalyst II was replaced by I3. The experimental results are shown in Table 12.

[0214] Table 12

[0215]

[0216] Application Example 44

[0217] Under anhydrous and anaerobic conditions in a glove box, a 350 mL thick-walled pressure bottle was sequentially charged with anhydrous toluene (20 mL) and AlEt2Cl (3 mL, 1 M in toluene). The pressure bottle was taken out of the glove box and connected to an ethylene gas line to be vacuumed and saturated with ethylene. After preheating and stirring for 10 min at 0.4 MPa and 30°C, methyl acrylate (0.50 M) and a dichloromethane (2 mL) solution of the α-diimine nickel complex II (5 μmol) were added, and the reaction was stirred for 30 min. After the reaction was completed, the reaction was terminated with 5% hydrochloric acid in ethanol. The polymer was precipitated, filtered, washed, and dried at 50°C under vacuum to constant weight to obtain a polymerization product. The experimental results are shown in Table 13.

[0218] Application Example 45

[0219] The experimental procedure was the same as in Application Example 44, except that methyl acrylate (0.50 M) was replaced with 5-norbornene-2-carboxylic acid methyl ester (0.10 M). The experimental results are shown in Table 13.

[0220] Application Example 46

[0221] The experimental procedure was the same as in Application Example 44, except that methyl acrylate (0.50 M) was replaced with allyl acetate (0.25 M). The experimental results are shown in Table 13.

[0222] Table 13

[0223]

[0224]

[0225] Application Example 47

[0226] Under anhydrous and anaerobic conditions in a glove box, a 350 mL thick-walled pressure bottle was sequentially charged with anhydrous toluene (20 mL) and AlEt2Cl (3 mL, 1 M in toluene). The pressure bottle was taken out of the glove box and connected to an ethylene gas line to be vacuumed and saturated with ethylene. After preheating and stirring for 10 min at 0.2 MPa and 30°C, 1-octene (0.5 M) and a dichloromethane (2 mL) solution of the α-diimine nickel complex II (10 μmol) were added, and the reaction was stirred for 30 min. After the reaction was completed, the reaction was terminated with 5% hydrochloric acid in ethanol. The polymer was precipitated, filtered, washed, and dried at 50°C under vacuum to constant weight to obtain a polymerization product. The experimental results are shown in Table 14.

[0227] Application Example 48

[0228] The experimental procedure was the same as that of Application Example 47, except that 1-octene (0.5 M) was changed to 1-octene (1.0 M). The experimental results are shown in Table 14.

[0229] Application Example 49

[0230] The experimental procedure was the same as that of Application Example 47, except that 1-octene (0.5 M) was changed to 1-octene (3.0 M). The experimental results are shown in Table 14.

[0231] Table 14

[0232]

[0233] Application Examples 47-49 show that I7 polymerizes with 1-octene of different concentrations to produce high-end polyethylene thermoplastic elastomer POE under the conditions of a pressure of 0.2 MPa and a reaction time of 30 min, and the elastic recovery rate of POE also obviously increases with the increase of the concentration of 1-octene. Figures 7-10 400 μmol / L of catalyst I7 polymerizes with 3.0 M of 1-octene at 30°C and 0.2 MPa for 30 min to prepare high-performance polyethylene-POE, and the strain performance of which can be as high as 2300%, and the elastic recovery rate can be as high as 71%.

[0234] Application Example 50

[0235] Under anhydrous and anaerobic conditions in a glove box, 20 mL of anhydrous toluene and 3 mL of AlEt2Cl (1 M in toluene) were sequentially added to a 350 mL thick-walled pressure-resistant bottle. The pressure-resistant bottle was taken out of the glove box and connected to an ethylene gas circuit to be vacuumized and then saturated with ethylene. After being preheated and stirred at 0.2 MPa and 30°C for 10 min, 10-undecen-1-ol (0.10 M) and a dichloromethane (2 mL) solution of α-diimine nickel complex I7 (10 μmol) were added, and the reaction was stirred for 30 min. After the reaction was completed, the reaction was terminated with 5% hydrochloric acid-containing ethanol. The polymer was precipitated, filtered, washed, and dried at 50°C under vacuum to constant weight to obtain a polymerization product. The specific experimental results are shown in Table 15.

[0236] Application Example 51

[0237] The experimental procedure was the same as that of Application Example 50, except that 10-undecen-1-ol (0.10 M) was changed to 9-decen-1-ol (0.10 M). The experimental results are shown in Table 15.

[0238] Application Example 50

[0239] The experimental procedure was the same as in Application Example 46, except that 10-undecen-1-ol (0.10 M) was replaced by 5-hexen-1-ol (0.10 M). The experimental results are shown in Table 15.

[0240] Application Example 50

[0241] The experimental procedure was the same as in Application Example 46, except that 10-undecen-1-ol (0.10 M) was replaced by butenoic acid (0.10 M). The experimental results are shown in Table 15.

[0242] Table 15

[0243]

[0244] As can be seen from Application Examples 1 to 34, the catalysts I1 to I7 of the present application can all catalyze the preparation of polyethylene with high activity, and at the same time can prepare ultrahigh molecular weight polyethylene with lower branching degree. In the polymerization of olefins, I1 to I7 utilize the large steric hindrance of the dibenzo barrelene skeleton to shield the steric hindrance of the metal back surface; at the same time, the large steric hindrance of the ortho aromatic substituent group inhibits chain transfer, reduces the molecular weight distribution of the polymer, greatly increases the molecular weight of the polymer, and the ultrahigh molecular weight polyethylene catalyzed by I2 is even as high as 833.3 x 10 4 g·mol -1 Before this, catalysts capable of preparing such high molecular weight polyethylene are extremely rare. With the increase of temperature, the introduction of these large steric hindrance aromatic substituents greatly enhances the stability of the nickel complex; and I1 can still catalyze the polymerization of ethylene with high activity of 7.32 x 10 6 g·mol -1 ·h -1 at 120℃, which fully proves the high thermal stability of such catalysts. In comparison with I1, I4 and I6, I2, I3, I5 and I7 introduce electron-withdrawing groups at different positions on different benzene rings, which greatly improves the activity of the catalysts. In addition, by adjusting the temperature, pressure and other conditions of the polymerization reaction, the highest activity of the catalyst can reach 1.0 x 10 8 g·mol -1 ·h -1 (Application Example 14).

[0245] The polymers prepared by I1 to I3 are ultrahigh molecular weight polyethylene thermoplastic elastomers. Through mechanical property testing of the polyethylene, it is found that the polyethylene prepared by the catalyst has good mechanical properties and tensile strength Figures 4-6 ). The stress value of the ultrahigh molecular weight thermoplastic elastomer prepared by I1 at 50℃ can reach 43 MPa, and the polyethylene prepared by I2 at 70℃ maintains ultrahigh molecular weight (833.3 x 10 4 g·mol -1) while having good tensile properties (maximum strain up to 770%). Figures 4-6 By introducing different electronic groups at the ortho or para position of benzene, the elimination of beta-H can be well inhibited, and the activity and molecular weight of the catalyst can be improved.

[0246] As can be seen from application examples 35-54, the catalysts I1, I2, I3 and I7 of the present application can all catalyze the preparation of polar functionalized polyolefins under certain conditions with high activity, and the highest activity reaches 13.34 x 10 5 g·mol -1 ·h -1 (application example 48), the insertion ratio of catalyst I7 in copolymerization with polar monomers reaches 1.22% (application example 51), in addition, I7 can also copolymerize with 1-octene to form an industrially usable co-soluble and blended additive POE (polyolefin elastomer), and through mechanical property testing of the POE material, it is found that the POE has excellent strain (2300%) and elastic recovery rate (71%) ( Figures 7-10 ).

[0247] The experimental results show that the alpha-diimine nickel complex provided by the present application has extremely high catalytic activity for olefin polymerization, can produce polyolefin materials with controllable ultrahigh molecular weight, and can produce functionalized high-end polyolefins.

[0248] The above is only a specific implementation of the present application, enabling those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features applied herein.

Claims

1. An α-diimine nickel complex characterized in that, The structural formula is shown as follows: 。 2. The process for the synthesis of the α-diimine nickel complex according to claim 1, characterized in that, It comprises the following steps: (1) the dibenzobulvalene shown in formula (II) is condensed with aniline compound shown in formula (III) under the catalysis of a first catalyst at 130 DEG C for 12-36 h to generate alpha-diimine compound shown in formula (IV), and the reaction route is shown as follows: Wherein, the structures of R1 and R2 are the same as those described in claim 1; (2) the alpha-diimine compound shown in formula (IV) is reacted with (DME)NiBr2 at 0-45 DEG C for 1-50 h to obtain alpha-diimine nickel complex I1-7; The first catalyst is zinc dichloride.

3. The method of synthesis of claim 2, wherein: In step (1), the molar ratio of dibenzobulvalene shown in formula (II) to aniline compound shown in formula (III) is 1:(2-3).

4. The method of synthesis of claim 2, wherein: In step (2), the molar ratio of alpha-diimine compound to (DME)NiBr2 is 1:(0.1-6).

5. Use of the α-diimine nickel complex according to claim 1 for the synthesis of polyolefins, characterized in that: The alpha-diimine nickel complex is used as a super-high-activity and high-thermal-stability catalyst to catalyze ethylene polymerization to prepare super-high-molecular-weight polyethylene thermoplastic elastomer and POE material.

6. Use according to claim 5, characterized in that: The end-alkenyl-containing compound is contacted with the alpha-diimine nickel complex and the alkyl aluminum reagent, and the end-alkenyl-containing compound is subjected to a catalyst homopolymerization reaction, the homopolymerization reaction is carried out in an organic solvent, the amount of the alpha-diimine nickel complex is 5-40 μmol / L, the homopolymerization reaction temperature is 0-150 DEG C, the pressure is 0.1-2.0 MPa, and the reaction time is 0.05-3.00 hours.

7. The use according to claim 5, characterized in that: The end-alkenyl-containing compound and the polar monomer are contacted with the alpha-diimine nickel complex and the alkyl aluminum reagent, and the end-alkenyl-containing compound and the polar monomer are subjected to a copolymerization reaction, the copolymerization reaction temperature is 0-50 DEG C, the copolymerization reaction pressure is 0.1-1 MPa, the reaction time is 0.05-3.00 hours, the concentration of the alpha-diimine nickel complex is 200-400 μmol / L, and the monomer concentration is 0.1-3.0 M; the polar monomer refers to an alpha-olefin containing a heteroatom, and at least one of the following is included: 10-undecylenic acid methyl ester, vinyltrimethoxysilane, 1-octene, 6-chloro-1-hexene, 10-undecenol, methyl acrylate, propylene acetate, and methyl norbornene acid.

8. Use according to claim 6, characterized in that: The concentration of the alpha-diimine nickel complex is 20 μmol / L, the homopolymerization reaction temperature is 30 DEG C, the pressure is 0.8 MPa, and the reaction time is 10 minutes, and the optimal catalytic effect can be obtained.

9. Use according to claim 7, characterized in that: 400 μmol / L of the catalyst I7 is polymerized with 3.0 M of 1-octene at 30 DEG C and 0.2 MPa for 30 min to prepare high-performance polyethylene-POE, and the strain performance thereof is up to 2300%, and the elastic recovery rate is up to 71%.

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