An ethylene copolymer and a polymerization method

Abstract

This invention discloses an ethylene copolymer containing ethylene structural units derived from ethylene and conjugated diene structures derived from conjugated dienes. This ethylene copolymer is formed by contacting ethylene and the conjugated diene with a transition metal complex of Formula I. In the ethylene copolymer according to this invention, the content of ethylene structural units can vary over a relatively wide range while maintaining a high content of cis-1,4-structural units.

Description

Technical Field

[0001] This invention relates to an ethylene copolymer containing ethylene structural units derived from ethylene and conjugated diene structural units derived from conjugated dienes; the invention also relates to a polymerization method for copolymerizing ethylene with conjugated dienes. Background Technology

[0002] Ethylene, as a widely used and readily available monomer, is extensively used in the plastics industry. Conjugated dienes, especially butadiene and isoprene, are the most important monomers for synthetic rubber. Due to the different polymerization mechanisms of conjugated dienes and α-olefins, copolymerization is difficult. Therefore, catalyzing the copolymerization of ethylene and conjugated dienes using the same catalytic system is a highly challenging task, and achieving their copolymerization has long been a focus of academic and industrial efforts. Developing transition metal complexes that combine high catalytic activity, high control over the structural regularity of conjugated diene structural units, and high copolymerization ability between ethylene and conjugated dienes is very attractive.

[0003] In 2015, Michiue et al. reported a series of silicon-bridged disubstituted indene zirconium catalysts for the preparation of ethylene / propylene and butadiene copolymers in the presence of hydrogen (K. Michiue, M. Mitani, T. Fujita, Catalysts 2015, 5, 2001-2017). The catalysts exhibited high activity and yielded polymers with high molecular weights. With increasing steric hindrance of the indene substituents, the vinyl content in the copolymers increased. However, the butadiene insertion rate in the resulting copolymers was low, and the copolymers contained cyclopropyl and cyclopentyl structures. Rare earth catalysts, due to their good affinity for conjugated dienes, have also been explored for the copolymerization of ethylene and conjugated dienes. Boisson et al. reported a series of neodymium thiocenyl catalysts that can efficiently catalyze the copolymerization of ethylene and butadiene (M. Llauro, C. Monnet, F. Barbotin, V. Monteil, R. Spitz, C. Boisson, Macromolecules 2001, 34, 6304-6311; H. Nsiri, I. Belaid, P. Larini, J. Thuilliez, C. Boisson, L. Perrin, ACS Catal. 2016, 6, 1028-1036). The copolymers contain a high butadiene content, primarily in the trans-1,4- structure. However, the polymer molecular weight is not high enough, and the polymer contains a cyclohexyl structure.

[0004] Transition metal compounds with heterocyclic fused five-membered ring π-ligands and their use in catalyzing monoolefin polymerization have been reported, exhibiting advantages such as high activity and high molecular weight. However, reports on their use in catalyzing ethylene-conjugated diene copolymerization are scarce. No reports have been found on heterocyclic fused dicrenecrolein rare earth catalysts and their application in ethylene-conjugated diene copolymerization. Summary of the Invention

[0005] One objective of this invention is to provide an ethylene copolymer containing ethylene structural units derived from ethylene and conjugated diene structural units derived from conjugated dienes. Another objective is to provide a polymerization method for copolymerizing ethylene and conjugated dienes. The ethylene copolymer and polymerization method employ a transition metal complex with a heterocyclic fused five-membered ring π-ligand as a catalyst. This complex can effectively regulate the copolymer composition of the copolymer while maintaining high structural regularity of the conjugated diene structural units in the copolymer.

[0006] According to a first aspect of the invention, an ethylene copolymer is provided, comprising ethylene structural units derived from ethylene and conjugated diene structures derived from conjugated dienes, the ethylene copolymer being formed by contacting ethylene and the conjugated diene with a transition metal complex of Formula I.

[0007]

[0008] In Formula I, Ln represents a lanthanide element, scandium, or yttrium;

[0009] R1, R2, R3, R4, R5, R6, R7, R8, R9 and R 10 Whether the two are the same or different, they are each independently hydrogen, C1-C 20 Alkyl, C6-C 30 aryl or -SiR 23 R 24 R 25 R 23 R 24 and R 25 Whether they are the same or different, they are each independently hydrogen or C1-C 20 Alkyl groups;

[0010] R 11 R 12 R 13 R 14 R 15 and R 16 Whether identical or different, each is independently hydrogen or a C1-C5 alkyl group;

[0011] E is O, S, or NR 17 R 17It is a C1-C5 alkyl group or a C6-C alkyl group. 12 Aryl groups.

[0012] According to a second aspect of the present invention, a polymerization method is provided, the method comprising contacting ethylene and a conjugated diene with a transition metal complex of Formula I to obtain an ethylene copolymer containing ethylene structural units derived from ethylene and a conjugated diene structure derived from the conjugated diene.

[0013]

[0014] In Formula I, Ln represents a lanthanide element, scandium, or yttrium;

[0015] R1, R2, R3, R4, R5, R6, R7, R8, R9 and R 10 Whether the two are the same or different, they are each independently hydrogen, C1-C 20 Alkyl, C6-C 30 aryl or -SiR 23 R 24 R 25 R 23 R 24 and R 25 Whether they are the same or different, they are each independently hydrogen or C1-C 20 Alkyl groups;

[0016] R 11 R 12 R 13 R 14 R 15 and R 16 Whether identical or different, each is independently hydrogen or a C1-C5 alkyl group;

[0017] E is O, S, or NR 17 R 17 It is a C1-C5 alkyl group or a C6-C alkyl group. 12 Aryl groups.

[0018] According to a third aspect of the present invention, the present invention provides an ethylene copolymer prepared by the method described in the second aspect of the present invention.

[0019] The ethylene copolymer and polymerization method according to the present invention employs a transition metal complex of Formula I as a catalyst. This transition metal complex exhibits high copolymerization performance, thus allowing the content of ethylene structural units in the ethylene copolymer of the present invention to vary within a relatively wide range to meet the requirements of different applications. Simultaneously, this transition metal complex also possesses good ability to adjust conjugated diene structural units; even with a high content of ethylene structural units, the content of conjugated diene structural units can maintain a high level of cis-1,4-structural units. Furthermore, the transition metal complex used in the polymerization method according to the present invention exhibits enhanced catalytic activity, effectively increasing the yield of the ethylene copolymer. Detailed Implementation

[0020] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0021] In this invention, the term "conjugated diene" refers to a compound whose molecular structure contains conjugated double bonds. In this invention, the conjugated diene may be selected from one or more compounds shown in Formula VI.

[0022]

[0023] In equation VI, R 20 R 21 and R 22 They may be the same or different, each selected from hydrogen and C1-C5 straight-chain or branched alkyl groups.

[0024] Specific examples of the conjugated diene may include, but are not limited to, butadiene and / or isoprene. Preferably, the conjugated diene is butadiene.

[0025] According to a first aspect of the invention, an ethylene copolymer is provided, comprising ethylene structural units derived from ethylene and conjugated diene structures derived from conjugated dienes, the ethylene copolymer being formed by contacting ethylene and the conjugated diene with a transition metal complex of Formula I.

[0026]

[0027] In Formula I, Ln represents a lanthanide element, scandium, or yttrium.

[0028] In this invention, the term "lanthanide elements" refers to the collective name of 15 elements from lanthanum (element 57) to lutetium (element 71) in the periodic table.

[0029] In Formula I, specific examples of Ln may include, but are not limited to: scandium (Sc), yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), or lutetium (Lu).

[0030] Preferably, in Formula I, Ln is gadolinium or scandium. More preferably, in Formula I, Ln is gadolinium.

[0031] In Equation I, R1, R2, R3, R4, R5, R6, R7, R8, R9 and R 10 Whether the two are the same or different, they are each independently hydrogen, C1-C 20 Alkyl, C6-C 30 aryl or -SiR 23 R 24 R 25 R 23 R 24 and R 25 Whether they are the same or different, they are each independently hydrogen or C1-C 20 Alkyl groups; preferably, R 23 R 24 and R 25 At least one of them is C1-C 20 Alkyl groups.

[0032] In this invention, C1-C 20 Alkyl groups include C1-C 20 Straight-chain alkyl, C3-C 20 Branched alkyl groups and C3-C 20 Specific examples of cycloalkyl groups may include, but are not limited to: methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, pentyl and its various isomers, hexyl and its various isomers, heptyl and its various isomers, octyl and its various isomers, nonyl and its various isomers, decyl and its various isomers, undecyl and its various isomers, dodecyl and its various isomers, tridecyl and its various isomers, tetradecyl and its various isomers, pentadecyl and its various isomers, hexadecyl and its various isomers, heptadecanyl and its various isomers, heptadecanyl and its various isomers, octadecyl and its various isomers, nonadecanyl and its various isomers, eicosyl and its various isomers, cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl.

[0033] In this invention, C6-C 30Specific examples of aryl groups may include, but are not limited to: phenyl, tolyl, ethylphenyl, propanylphenyl (wherein, the propyl group may be n-propyl or isopropyl), butylphenyl (wherein, the butyl group may be n-butyl, sec-butyl, isobutyl or tert-butyl), naphthyl, anthraceneyl or phenanthryl.

[0034] In a preferred embodiment, in Formula I, R1 and R6 are each independently a C1-C5 alkyl group, and R2, R4, R7, and R9 are each independently a C6-C5 alkyl group. 12 Aryl groups, R3, R5, R8 and R 10 All are hydrogen. In this preferred embodiment, R1 and R6 are preferably methyl, and R2, R4, R7 and R9 are preferably phenyl. In this preferred embodiment, Ln is preferably gadolinium.

[0035] In another preferred embodiment, in formula I, R1, R4, R6, and R9 are each independently C1-C1. 20 The alkyl group, R2 and R7 are each independently C6-C. 30 Aryl groups, R3, R5, R8 and R 10 All are hydrogen. In this preferred embodiment, R1, R4, R6, and R9 are each independently preferably C1-C5 alkyl groups, and R2 and R7 are each independently preferably C6-C5 alkyl groups. 12 The aryl group. More preferably, R1, R4, R6, and R9 are methyl or isopropyl, and R2 and R7 are phenyl. Even more preferably, R1 and R6 are methyl, R4 and R9 are methyl or isopropyl, and R2 and R7 are phenyl. In this preferred embodiment, Ln is preferably gadolinium.

[0036] In yet another preferred embodiment, in formula I, R1, R4, R6, and R9 are each independently C1-C1. 20 The alkyl group, R2 and R7 are each independently C6-C. 30 Aryl, R5 and R 10 Both are hydrogen, and R3 and R8 are independently -SiR. 23 R 24 R 25 R 23 R 24 and R 25 Whether they are the same or different, each is independently C1-C 20 Alkyl groups. In this preferred embodiment, R1, R4, R6, and R9 are each independently preferably C1-C5 alkyl groups, and R2 and R7 are each independently preferably C6-C5 alkyl groups. 12 The aryl group, R3 and R8 are each independently preferred to be -SiR 23 R 24 R 25 R 23 R24 and R 25 Whether the groups are the same or different, each is independently hydrogen or a C1-C5 alkyl group, and R 23 R 24 and R 25 At least one of them is a C1-C5 alkyl group. In this preferred embodiment, R1, R4, R6 and R9 are more preferably methyl, R2 and R7 are more preferably phenyl, and R3 and R8 are each more preferably -SiR. 23 R 24 R 25 R 23 R 24 and R 25 All are methyl groups. In this preferred embodiment, Ln is preferably gadolinium.

[0037] In formula I, R 11 R 12 R 13 R 14 R 15 and R 16 Whether identical or different, each is independently hydrogen or a C1-C5 alkyl group. Preferably, in formula I, R 11 R 12 R 13 R 14 R 15 and R 16 Whether the same or different, each is independently hydrogen or a C1-C5 alkyl group, and R 11 R 12 and R 13 At least one of them is a C1-C5 alkyl group, R 14 R 15 and R 16 At least one of them is a C1-C5 alkyl group. More preferably, in formula I, R 11 R 12 R 13 R 14 R 15 and R 16 Whether the same or different, each is independently hydrogen or a C1-C5 alkyl group, and R 11 R 12 and R 13 At least two of them are C1-C5 alkyl groups, R 14 R 15 and R 16 At least two of them are C1-C5 alkyl groups. More preferably, in formula I, R... 11 R 12 R 13 R 14 R 15 and R16 Whether identical or different, each is independently a C1-C5 alkyl group. More preferably, in formula I, R 11 R 12 R 13 R 14 R 15 and R 16 All are methyl groups.

[0038] In Equation I, E represents O, S, or NR. 17 R 17 It is a C1-C5 alkyl group or a C6-C alkyl group. 12 The aryl group. Preferably, in formula I, E is S.

[0039] According to the ethylene copolymer of the present invention, the transition metal complex is preferably a complex shown in Formula II, Formula III, Formula IV, or Formula V.

[0040]

[0041]

[0042] According to the ethylene copolymer of the present invention, the transition metal complex is particularly preferably a complex represented by formula II, formula IV or formula V.

[0043] The transition metal complex can be prepared using a method comprising the following steps:

[0044] Step 1: In the presence of organolithium, the precursor compound is contacted with a heterocyclic compound selected from the compounds shown in Formula 2-2-1 and Formula 2-2-2.

[0045] Step 2: Contact the mixture obtained in Step 1 with the amine shown in Formula 2-3.

[0046] The precursor compound is selected from the compounds shown in Formula 2-1.

[0047] LnX (Equation 2-1)

[0048] In Formula 2-1, Ln is a lanthanide element, scandium or yttrium, preferably gadolinium or scandium, and more preferably gadolinium;

[0049] X is a halogen atom, such as fluorine, chlorine, bromine or iodine, preferably chlorine;

[0050]

[0051] In equations 2-2-1 and 2-2-2, R 201 R 202 R 203 R 204 and R205 Whether the two are the same or different, they are each independently hydrogen, C1-C 20 Alkyl, C6-C 30 aryl or -SiR 23 R 24 R 25 R 23 R 24 and R 25 Whether they are the same or different, they are each independently hydrogen or C1-C 20 Alkyl groups;

[0052] In Equations 2-2-1 and 2-2-2, E is O, S, or NR. 17 R 17 It is a C1-C5 alkyl group, C6-C 12 The aryl group is preferably S;

[0053]

[0054] In Equation 2-3, R 206 R 207 R 208 R 209 R 210 and R 211 Whether identical or different, each is independently hydrogen or a C1-C5 alkyl group.

[0055] M is an alkali metal atom, such as lithium, sodium, or potassium, preferably sodium or potassium, and more preferably potassium.

[0056] In the preparation method described above, the mixture obtained in step 1 is directly used as the raw material in step 2 for reaction with the amine without separation. This eliminates the need for separation, which not only increases the complexity and cost of the process but also negatively impacts the yield of the target product due to material loss. In this method, using the mixture obtained in step 1 directly in step 2 simplifies the operation, reduces costs, and avoids adversely affecting the yield of the target product.

[0057] In the preparation method described, R in formulas 2-2-1 and 2-2-2 201 R 202 R 203 R 204 and R 205 The corresponding R1, R2, R3, R4, R5, R6, R7, R8, R9 and R in the compound shown in Formula I. 10 Specific examples are those that yield compounds represented by Formula I, and will not be elaborated upon here.

[0058] In the preparation method described, R in formula 2-3206 R 207 R 208 R 209 R 210 and R 211 R corresponds to the compound shown in Formula I 11 R 12 R 13 R 14 R 15 and R 16 Specific examples are those that yield compounds represented by Formula I, and will not be elaborated upon here.

[0059] In the preparation method, in step 1, the precursor compound is contacted with the heterocyclic compound in the presence of organolithium, wherein the organolithium is preferably an organic monolithium compound, more preferably a compound represented by formula VII.

[0060] R 26 Li (Form VII)

[0061] In equation VII, R 26 For C1-C 10 Alkyl groups, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, hexyl (including various isomers of hexyl), heptyl (including various isomers of heptyl), octyl (including various isomers of octyl), nonyl (including various isomers of nonyl), or decyl (including various isomers of decyl).

[0062] Specific examples of the organolithium may include, but are not limited to, one or more of the following: ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, and isobutyl lithium.

[0063] Preferably, the organolithium is one or more selected from the group consisting of n-butyllithium, sec-butyllithium, isobutyllithium, and tert-butyllithium. More preferably, the organolithium is n-butyllithium.

[0064] In step 1, the contact temperature between the precursor compound and the heterocyclic compound can be 0-65°C, and the contact duration can be 1-120 hours, preferably 1.2-80 hours, more preferably 1.5-40 hours, and even more preferably 2-10 hours. In step 1, the precursor compound and the heterocyclic compound lithium salt are contacted in a first solvent, preferably one or more of tetrahydrofuran, diethyl ether, dioxane, and hexane. The precursor compound and the heterocyclic compound can be separately mixed with a portion of the first solvent to form a solution. The solution containing the precursor compound is then mixed with the solution containing the heterocyclic compound, thereby allowing the precursor compound and the heterocyclic compound lithium salt to react.

[0065] In step 1, it is preferable to first contact the organic lithium with the heterocyclic compound to form a lithium salt, and then contact it with the precursor compound. The structure of the lithium salt is shown in Formulas 2-4.

[0066]

[0067] The heterocyclic compound can be dissolved in a first solvent and placed in an environment of -78°C to 0°C, and then alkyllithium is added to carry out the reaction. The reaction temperature of the heterocyclic compound with the alkyllithium is preferably -78°C to 60°C, more preferably -50°C to 50°C, and even more preferably -10°C to 30°C; the reaction time is preferably 0.8-10 h, more preferably 0.8-8 h, and even more preferably 1-5 h.

[0068] In the preparation method, the mixture formed by contacting the precursor compound and the heterocyclic compound in step 1 is not separated and is directly contacted with the amine in step 2, which is the transition metal complex. In step 2, the mixture obtained in step 1 is preferably contacted with the amine in a second solvent, preferably one or more of toluene, xylene, and chlorobenzene. Preferably, at least a portion of the first solvent is removed from the mixture obtained in step 1 to obtain a mixture with at least a portion of the first solvent removed, and this mixture is then mixed with the second solvent, thereby allowing the contact in step 2 to take place in the second solvent.

[0069] In the preparation method, in step 2, the mixture obtained in step 1 can be contacted with the amine at a temperature of 0-30°C for a duration of 1-48 hours.

[0070] In the preparation method, the transition metal complex according to the present invention can be separated from the mixture obtained in step 2 using conventional methods. In a preferred embodiment, at least a portion of the second solvent in the reaction mixture obtained in step 2 can be removed, a third solvent can be added to the reaction mixture to which at least a portion of the second solvent has been removed, followed by solid-liquid separation, collection of the liquid phase, removal of the solvent from the liquid phase, and the remaining solid phase being the transition metal complex. The third solvent can be one or more of hexane, heptane, and toluene.

[0071] According to the ethylene copolymer of the present invention, the transition metal complex is contacted with ethylene and a conjugated diene in the presence of a co-catalyst, causing the ethylene and the conjugated diene to undergo a polymerization reaction to obtain the ethylene copolymer. The co-catalyst can be a commonly used co-catalyst in the field of olefin polymerization.

[0072] In a preferred embodiment, the cocatalyst is an organoaluminum compound and / or an organoboron compound.

[0073] The organoaluminum compound is preferably an aluminum oxane and / or a compound of formula V.

[0074]

[0075] In formula V, R 17 R 18 and R 19 Whether the two are the same or different, they are each independently selected from hydrogen, C1-C 10 Alkyl, C1-C 10 alkoxy groups, C6-C 20 aryl, C7-C 15 alkylaryl, C7-C 15 Aryl groups and hydrogen atoms, and R 17 R 18 and R 19 They are not both hydrogen atoms.

[0076] The C1-C 10 Alkyl groups include C1-C 10 Straight-chain alkyl, C3-C 10 Branched alkyl groups and C3-C 10 Specific examples of cycloalkyl groups may include, but are not limited to: methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, pentyl and its various isomers, hexyl and its various isomers, heptyl and its various isomers, octyl and its various isomers, nonyl and its various isomers, decyl and its various isomers, cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl.

[0077] The C1-C 10 Specific examples of alkoxy groups may include, but are not limited to: methoxy, ethoxy, propoxy, and butoxy.

[0078] The C6-C 20 Specific examples of aryl groups may include, but are not limited to: phenyl, tolyl, ethylphenyl, propanylphenyl (wherein, the propyl group may be n-propyl or isopropyl), butylphenyl (wherein, the butyl group may be n-butyl, sec-butyl, isobutyl or tert-butyl), naphthyl, anthraceneyl or phenanthryl.

[0079] The alkylaryl group refers to an aryl group having an alkyl substituent. Specific examples of the alkylaryl group may include, but are not limited to, tolyl, ethylphenyl, dimethylphenyl, and diethylphenyl.

[0080] The aralkyl group refers to an alkyl group having an aryl substituent. Specific examples of the aralkyl group may include, but are not limited to, benzyl, phenethyl, 1-phenylpropyl, 2-phenylpropyl, and 3-phenylpropyl.

[0081] Specific examples of the organoaluminum compounds may include, but are not limited to: diethylaluminum hydride, di-n-propylaluminum hydride, di-n-butylaluminum hydride, diisobutylaluminum hydride, diphenylaluminum hydride, di(p-tolyl)aluminum hydride, dibenzylaluminum hydride, phenylethylaluminum hydride, phenyl-n-propylaluminum hydride, p-tolylethylaluminum hydride, p-tolyl-n-propylaluminum hydride, p-tolylisopropylaluminum hydride, benzylethylaluminum hydride, benzyl-n-propylaluminum hydride, benzylisopropylaluminum hydride, ethylaluminum dihydride, butyl dihydride. Aluminum chloride, isobutylaluminum dihydrogen hydride, octylaluminum dihydrogen hydride, pentylaluminum dihydrogen hydride, diethylaluminum ethoxide, dipropylaluminum ethoxide, trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisopropylaluminum, tri-n-butylaluminum, triisobutylaluminum, tripentylaluminum, trihexylaluminum, tricyclohexylaluminum, trioctylaluminum, triphenylaluminum, tri(p-tolyl)aluminum, tribenzylaluminum, ethyl diphenylaluminum, ethyl di(p-tolyl)aluminum, ethyl di(benzyl)aluminum, diethylphenylaluminum, diethyl p-tolyl)aluminum, and diethylbenzylaluminum.

[0082] In a preferred example, in equation V, R 17 R 18 and R 19 It is hydrogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, or isobutyl, and R 17 R 18 and R 19 At most one of them is hydrogen. More preferably, in formula V, R 17 R 18 and R 19 It is hydrogen or butyl, and R 17 R 18 and R 19 At most one of them is hydrogen.

[0083] In a preferred embodiment, the organoaluminum compound is preferably triisobutylaluminum and / or diisobutylaluminum hydride.

[0084] The organoboron compound is preferably an organoborate. The organoborate is an ionic compound composed of a borate anion and a cation.

[0085] Specific examples of the borate anion may include, but are not limited to: tetraphenylborate, tetra(monofluorophenyl)borate, tetra(difluorophenyl)borate, tetra(trifluorophenyl)borate, tetra(tetrafluorophenyl)borate, tetra(pentafluorophenyl)borate, tetra(tetrafluoromethylphenyl)borate, tetra(tolyl)borate, tetra(xylyl)borate, (triphenyl-pentafluorophenyl)borate, [tri(pentafluorophenyl)phenyl]borate, and undecanoyl-7,8-dicarboundecanoate.

[0086] Specific examples of the cations may include, but are not limited to: carbium cations, oxonium cations, ammonium cations, phosphine cations, cycloheptatrienyl cations, and ferrocene cations containing transition metals. Among them, carbium cations include trisubstituted carbium cations, such as triphenylcarbium cations and tri(substituted phenyl)carbium cations. More specific examples of tri(substituted phenyl)carbium cations include tri(tolyl)carbium cations. Specific examples of ammonium cations may include, but are not limited to: trialkylammonium cations, such as trimethylammonium cations, triethylammonium cations, tripropylammonium cations, and tributylammonium cations; N,N-dialkylphenylammonium cations, such as N,N-dimethylphenylammonium cations, N,N-diethylphenylammonium cations, and N,N-2,4,6-pentamethylphenylammonium cations; and dialkylammonium cations, such as diisopropylammonium cations and dicyclohexylammonium cations. Specific examples of phosphine cations may include, but are not limited to, triaryl cations, such as triphenylphosphine cation, tri(tolyl)phosphine cation, and tri(xyl)phosphine cation.

[0087] In a preferred embodiment, the organoboron compound is preferably N,N-dimethylphenylammonium tetra(pentafluorophenyl)borate and / or triphenylmethyl-tetra(pentafluorophenyl)borate.

[0088] In the catalyst composition, the organoaluminum compound and organoboron compound, which serve as co-catalysts, can be used alone or in combination.

[0089] In a preferred embodiment, the cocatalyst is an organoaluminum compound and an organoboron compound. More preferably, the cocatalyst is triisobutylaluminum and N,N-dimethylphenylammonium tetra(pentafluorophenyl)borate. In this preferred embodiment, the molar ratio of the organoaluminum compound to the organoboron compound in the cocatalyst can be 1:0.01-100, preferably 1:0.1-90, more preferably 1:0.5-60, where the organoaluminum compound is calculated as aluminum and the organoboron compound as boron. In this preferred embodiment, the amount of the cocatalyst can be conventionally selected. When the cocatalyst contains an organoboron compound, the molar ratio of the transition metal complex to the organoboron compound is preferably 1:0.1-10, more preferably 1:0.5-5.

[0090] According to the ethylene copolymer of the present invention, the content of ethylene structural units in the ethylene copolymer can vary within a relatively wide range. Generally, based on the total amount of the ethylene copolymer, the content of ethylene structural units is 80 mol% or less, preferably 5-70 mol%, more preferably 10-60 mol%.

[0091] According to the ethylene copolymer of the present invention, by employing the aforementioned transition metal complex, not only can the content of ethylene structural units in the ethylene copolymer be effectively controlled, but the structural regularity of the conjugated diene can also be controlled, so that the conjugated diene structural units have a high degree of structural regularity. According to the ethylene copolymer of the present invention, based on the total amount of structural units derived from the conjugated diene, the content of cis-1,4-structural units is 85 mol% or more, preferably 90 mol% or more, more preferably 95 mol% or more, and even more preferably 98 mol% or more.

[0092] In this invention, the content of ethylene structural units and cis-1,4-structural units in the ethylene copolymer is determined by carbon nuclear magnetic resonance spectroscopy (CMR). 13 NMR (Non-Metrological Analytical) determination.

[0093] According to the ethylene copolymer of the present invention, the number-average molecular weight (M) of the ethylene copolymer n The molecular weight distribution index (M0.05) can range from 50,000 to 2,000,000, preferably from 80,000 to 1,500,000. According to the present invention, the molecular weight distribution index (M0.05) of the ethylene copolymer is... w / M n The value can be 1.2-5, preferably 1.5-4.

[0094] In this invention, the molecular weight distribution index of the ethylene copolymer is determined by gel permeation chromatography, with monodistributed polystyrene as the standard sample.

[0095] The ethylene copolymer according to the present invention can be a random copolymer.

[0096] According to a second aspect of the present invention, a polymerization method is provided, the method comprising contacting ethylene and a conjugated diene with a transition metal complex of Formula I to obtain an ethylene copolymer containing ethylene structural units derived from ethylene and a conjugated diene structure derived from the conjugated diene.

[0097]

[0098] In Formula I, Ln represents a lanthanide element, scandium, or yttrium;

[0099] R1, R2, R3, R4, R5, R6, R7, R8, R9 and R 10Whether the two are the same or different, they are each independently hydrogen, C1-C 20 Alkyl, C6-C 30 aryl or -SiR 23 R 24 R 25 R 23 R 24 and R 25 Whether they are the same or different, they are each independently hydrogen or C1-C 20 Alkyl groups;

[0100] R 11 R 12 R 13 R 14 R 15 and R 16 Whether identical or different, each is independently hydrogen or a C1-C5 alkyl group;

[0101] E is O, S, or NR 17 R 17 It is a C1-C5 alkyl group or a C6-C alkyl group. 12 Aryl groups.

[0102] The transition metal complexes shown in Formula I and their preparation methods have been described in detail above and will not be repeated here.

[0103] According to the polymerization method of the present invention, the transition metal complex is contacted with ethylene and a conjugated diene in the presence of a co-catalyst, causing the ethylene and the conjugated diene to undergo a polymerization reaction to obtain an ethylene copolymer. The co-catalyst and its dosage have been described in detail above and will not be repeated here.

[0104] The polymerization method according to the present invention can employ conventional polymerization methods. In one embodiment, the polymerization method according to the present invention employs solution polymerization. In this embodiment, the solvent used in the solution polymerization can be one or more selected from toluene, hexane, and chlorobenzene.

[0105] According to the polymerization method of the present invention, the temperature for polymerizing ethylene with conjugated diene can be from -100°C to 150°C, preferably from 10 to 50°C.

[0106] According to a third aspect of the present invention, the present invention provides an ethylene copolymer prepared by the method described in the second aspect of the present invention.

[0107] The present invention will be described in detail below with reference to embodiments, but this does not limit the scope of the invention.

[0108] In the following examples and comparative examples, the molecular weight and molecular weight distribution index (M) of the polymers are... w / Mn The assay was performed using an Agilent Technologies 1260 Infinity II high-temperature gel permeation chromatograph, employing two MIXD-B columns (300 × 7.5 mm) and one Guard column (50 × 7.5 mm). The mobile phase was trichlorobenzene, with a flow rate of 1 mL / min; the sample concentration was 1 mg / mL, and the injection volume was 200 μL; the test temperature was 150 °C; and monodistributed polystyrene was used as the standard sample.

[0109] In the following examples and comparative examples, nuclear magnetic resonance (NMR) spectroscopy was performed using a commercially available 400MHz NMR spectrometer from Bruker. Polybutadiene was tested at room temperature with deuterated chloroform as the solvent and tetramethylsilane (TMS) as the internal standard. Ethylene-butadiene copolymer was tested at 100°C with deuterated tetrachloroethane as the solvent. The content of cis-1,4 structural units in the butadiene structural units was determined based on the polymer... 13 Calculations from the C NMR spectrum showed that the peak at 26.5–27.5 ppm corresponded to carbon atoms in the cis-1,4 structural unit, while the peaks at 26.5–27.5 ppm and 31.5–32.5 ppm corresponded to carbon atoms in the butadiene structural unit; the content of ethylene structural units in the copolymer was determined according to… 13 Calculations from the C10 NMR spectra showed that the peaks at 28.5–30.0 ppm corresponded to carbon atoms in the ethylene structural unit, while the peaks at 26.5–27.5 ppm and 31.5–32.5 ppm corresponded to carbon atoms in the butadiene structural unit. Here, the cis structural unit refers to a structural unit with a cis configuration, and the cis-1,4-structural unit refers to a structural unit formed by 1,4-polymerization of butadiene with a cis configuration.

[0110] Preparation Examples 1-4 were used to prepare transition metal complexes according to the present invention.

[0111] Preparation Example 1

[0112] Synthesis of bis(2-methyl-3,5-diphenyl-6-hydrocyclopentadienthiophene)gadolinium bis(trimethylsilylamide) (the complex shown in Formula II)

[0113]

[0114] Under a nitrogen atmosphere, 20 mL of a THF solution containing 1.819 g (6.2 mmol) of lithium salt synthesized from 2-methyl-3,5-diphenyl-6-hydrocyclopentadienthiophene and n-butyllithium was slowly added dropwise to 40 mL of dCl3 (0.791 g, 3 mmol). The mixture was then stirred at 65 °C for 6 hours. Afterward, the THF was distilled off under reduced pressure, and 50 mL of toluene was added. Then, 20 mL of a toluene solution of KN(SiMe3)2 (0.519 g, 2.6 mmol) was slowly added dropwise to the mixture, followed by stirring at room temperature (25 °C) for 12 hours. The toluene was then distilled off under reduced pressure, 100 mL of hexane was added, and the precipitate was removed by filtration. Subsequently, the hexane was distilled off under reduced pressure to give the target product (1.336 g, 50% yield) as a pale yellow solid. The product was analyzed using elemental analysis, and the results were: C 61.91; H 5.42.

[0115] Preparation Example 2

[0116] Synthesis of bis(2,5-dimethyl-3-phenyl-6-hydrocyclopentadienthiophene)scandium bis(dimethylsilylamide) (the complex shown in Formula III)

[0117]

[0118] The transition metal complex was prepared using the same method as in Preparation Example 1, except that ScCl3 was used instead of GdCl3, 2,5-dimethyl-3-phenyl-6-hydrocyclopentadienthiophene was used instead of 2-methyl-3,5-diphenyl-6-hydrocyclopentadienthiophene, and KN(SiMe2H)2 was used instead of KN(SiMe3)2. The target product (1.183 g, yield 63%) was obtained as a pale yellow solid. Elemental analysis of the product yielded the following results: C 65.91; H 6.76.

[0119] Preparation Example 3

[0120] Synthesis of bis(2-methyl-3-phenyl-5-isopropyl-6-hydro-cyclopentadienthiophene)gadolinium bis(trimethylsilylamide) (the complex shown in Formula IV)

[0121]

[0122] The transition metal complex was prepared using the same method as in Preparation Example 1, except that 2-methyl-3,5-diphenyl-6-hydrocyclopentadienthiophene was used instead of 2-methyl-3,5-diphenyl-6-hydrocyclopentadienthiophene in Preparation Example 1, yielding a white solid target product (1.357 g, yield 55%). Elemental analysis of the product yielded the following results: C 58.28; H 6.36.

[0123] Preparation Example 4

[0124] Synthesis of bis(2,5-dimethyl-3-phenyl-4-trimethylsilyl-6-hydro-cyclopentadienthiophene)gadolinium bis(trimethylsilylamide) (the complex shown in Formula V)

[0125]

[0126] The transition metal complex was prepared using the same method as in Preparation Example 1, except that 2-methyl-3,5-diphenyl-6-hydrocyclopentadienthiophene was used instead of 2,5-dimethyl-4-trimethylsilyl-6-hydrocyclopentadienthiophene in Preparation Example 1, yielding a white solid target product (1.232 g, yield 45%). Elemental analysis of the product yielded the following results: C 55.27; H 6.63.

[0127] Preparation of Comparative Example 1

[0128] Complex VI was synthesized according to the method described in Dalton Trans., 2008, 2531-2533.

[0129]

[0130] Examples 1-8 illustrate the ethylene copolymer and polymerization method of the present invention.

[0131] Example 1

[0132] In a glove box under an argon atmosphere, 30.34 mg of the complex shown in Formula II and 27.24 mg of N,N-dimethylphenylammonium tetra(pentafluorophenyl)borate were dissolved in 8 mL of toluene in a glass bottle to obtain a catalyst solution. In another glass bottle, 2 mL of 1 M triisobutylaluminum hexane solution and 7 mL of toluene were added to obtain a triisobutylaluminum solution.

[0133] 120 g of toluene, triisobutylaluminum solution, and 14 g of butadiene were added sequentially to a 500 mL autoclave. Ethylene was then introduced at 0.8 MPa, and after saturation, a catalyst solution was added. Polymerization was carried out at 40 °C for 60 minutes. After polymerization, the product was poured into a large amount of ethanol containing hydrochloric acid (2‰ by weight, hydrochloric acid is calculated as HCl), precipitated, and the copolymer was separated by filtration. After washing with ethanol, the copolymer was dried in a vacuum oven until its weight no longer decreased, yielding 14.6 g of copolymer. GPC analysis determined the number average molecular weight (Mn) of the copolymer. n The molecular weight distribution index (M) is 105,000. w / M n The value is 1.6.

[0134] Nuclear magnetic resonance spectroscopy analysis determined that the molar content of butadiene structural units derived from butadiene in the prepared copolymer was 86.2%; based on the total amount of butadiene structural units, the molar content of cis-1,4-structural units was 95.2%.

[0135] Example 2

[0136] In a glove box under an argon atmosphere, 28.03 mg of the complex shown in Formula III and 31.36 mg of triphenylmethyl-tetra(pentafluorophenyl)borate were dissolved in 8 mL of toluene in a glass bottle to obtain a catalyst solution. In another glass bottle, 2 mL of 1 M triisobutylaluminum hexane solution and 7 mL of toluene were added to obtain a triisobutylaluminum solution.

[0137] 120 g of toluene, triisobutylaluminum solution, and 14 g of butadiene were added sequentially to a 500 mL autoclave. Ethylene was then introduced at 0.8 MPa, and after saturation, a catalyst solution was added. Polymerization was carried out at room temperature (25 °C) for 180 minutes. After polymerization, the product was poured into a large amount of ethanol containing hydrochloric acid (2‰ by weight, hydrochloric acid is calculated as HCl), precipitated, and the copolymer was separated by filtration. After washing with ethanol, the copolymer was dried in a vacuum oven until its weight no longer decreased, yielding 13.2 g of copolymer. GPC analysis determined the number average molecular weight (M0.05) of the copolymer. n The molecular weight distribution index (M) is 131,000. w / M n The value is 3.7.

[0138] Nuclear magnetic resonance spectroscopy analysis determined that the molar content of butadiene structural units derived from butadiene in the prepared copolymer was 65.2%; based on the total amount of butadiene structural units, the molar content of cis-1,4-structural units was 90.5%.

[0139] Example 3

[0140] In a glove box under an argon atmosphere, 31.03 mg of the complex shown in Formula V and 27.24 mg of N,N-dimethylphenylammonium tetra(pentafluorophenyl)borate were dissolved in 8 mL of toluene in a glass bottle to obtain a catalyst solution. In another glass bottle, 2 mL of 1 M diisobutylaluminum hydride hexane solution and 7 mL of toluene were added to obtain a diisobutylaluminum hydride solution.

[0141] 120 g of toluene, diisobutylaluminum hydride solution, and 14 g of butadiene were added sequentially to a 500 mL autoclave. Then, ethylene was introduced at 0.8 MPa, and after saturation, a catalyst solution was added. Polymerization was carried out at room temperature (25 °C) for 180 minutes. After polymerization, the product was poured into a large amount of ethanol containing hydrochloric acid (2‰ by weight, hydrochloric acid is calculated as HCl), precipitated, and the copolymer was separated by filtration. After washing with ethanol, the copolymer was dried in a vacuum oven until its weight no longer decreased, thus obtaining 12.1 g of copolymer. GPC analysis determined the number average molecular weight (M0.05) of the copolymer. n The molecular weight distribution index (M) is 288,000. w / M n The value is 2.4.

[0142] Nuclear magnetic resonance spectroscopy analysis determined that the molar content of butadiene structural units derived from butadiene in the copolymer was 78.3%; based on the total amount of butadiene structural units, the molar content of cis-1,4-structural units was greater than 99%.

[0143] Example 4

[0144] In a glove box under an argon atmosphere, 28.03 mg of the complex shown in Formula III and 27.24 mg of N,N-dimethylphenylammonium tetra(pentafluorophenyl)borate were dissolved in 8 mL of toluene in a glass bottle to obtain a catalyst solution. In another glass bottle, 2 mL of 1 M triisobutylaluminum hexane solution and 7 mL of toluene were added to obtain a triisobutylaluminum solution.

[0145] 120 g of toluene, triisobutylaluminum solution, and 14 g of butadiene were added sequentially to a 500 mL autoclave. Ethylene was then introduced at 1.2 MPa, and after saturation, a catalyst solution was added. Polymerization was carried out at 40 °C for 60 minutes. After polymerization, the product was poured into a large amount of ethanol containing hydrochloric acid (2‰ by weight, hydrochloric acid is calculated as HCl), precipitated, and the copolymer was separated by filtration. After washing with ethanol, the copolymer was dried in a vacuum oven until its weight no longer decreased, yielding 6.5 g of copolymer. GPC analysis determined the number average molecular weight (M0.05) of the copolymer. n The molecular weight distribution index (M) is 123,000. w / M n The value is 3.1.

[0146] Nuclear magnetic resonance spectroscopy analysis determined that the molar content of butadiene structural units derived from butadiene in the prepared copolymer was 48.4%; based on the total amount of butadiene structural units, the molar content of cis-1,4-structural units was 90.2%.

[0147] Example 5

[0148] In a glove box under an argon atmosphere, 30.34 mg of the complex shown in Formula II and 27.24 mg of N,N-dimethylphenylammonium tetra(pentafluorophenyl)borate were dissolved in 8 mL of toluene in a glass bottle to obtain a catalyst solution. In another glass bottle, 2 mL of 1 M triisobutylaluminum hexane solution and 7 mL of toluene were added to obtain a triisobutylaluminum solution.

[0149] 120 g of toluene, triisobutylaluminum solution, and 14 g of butadiene were added sequentially to a 500 mL autoclave. Ethylene was then introduced at 0.8 MPa, and after saturation, a catalyst solution was added. Polymerization was carried out at room temperature (25 °C) for 180 minutes. After polymerization, the product was poured into a large amount of ethanol containing hydrochloric acid (2‰ by weight, hydrochloric acid is calculated as HCl), precipitated, and the copolymer was separated by filtration. After washing with ethanol, the copolymer was dried in a vacuum oven until its weight no longer decreased, yielding 5.14 g of copolymer. GPC analysis determined the number average molecular weight (M0.05) of the copolymer. n The molecular weight distribution index (M) is 83,000. w / M n The value is 2.7.

[0150] Nuclear magnetic resonance spectroscopy analysis determined that the molar content of butadiene structural units derived from butadiene in the prepared polymer was 85.6%; based on the total amount of butadiene structural units, the molar content of cis-1,4-structural units was 98.5%.

[0151] Example 6

[0152] In a glove box under argon atmosphere, 24.73 mg of the complex shown in Formula IV and 27.67 mg of triphenylmethyl-tetra(pentafluorophenyl)borate were dissolved in 8 mL of toluene in a glass bottle to obtain a catalyst solution. In another glass bottle, 2 mL of 1 M triisobutylaluminum hexane solution and 7 mL of toluene were added to obtain a triisobutylaluminum solution.

[0153] 120 g of toluene, triisobutylaluminum solution, and 14 g of butadiene were added sequentially to a 500 mL autoclave. Ethylene was then introduced at 0.4 MPa, and after saturation, a catalyst solution was added. Polymerization was carried out at room temperature (25 °C) for 180 minutes. After polymerization, the product was poured into a large amount of ethanol containing hydrochloric acid (2‰ by weight, hydrochloric acid is calculated as HCl), precipitated, and the copolymer was separated by filtration. After washing with ethanol, the copolymer was dried in a vacuum oven until its weight no longer decreased, yielding 14.1 g of copolymer. GPC analysis determined the number average molecular weight (M0.05) of the copolymer. n The molecular weight distribution index (M) is 91,000. w / M n The value is 2.4.

[0154] Nuclear magnetic resonance spectroscopy analysis determined that the molar content of butadiene structural units derived from butadiene in the prepared polymer was 89.5%; based on the total amount of butadiene structural units, the molar content of cis-1,4-structural units was 98.5%.

[0155] Example 7

[0156] In a glove box under an argon atmosphere, 8.24 mg of the complex shown in Formula IV and 9.22 mg of triphenylmethyl-tetra(pentafluorophenyl)borate were dissolved in 8 mL of toluene in a glass bottle to obtain a catalyst solution. In another glass bottle, 1 mL of 1M triisobutylaluminum hexane solution and 7 mL of toluene were added to obtain a triisobutylaluminum solution.

[0157] 120 g of toluene, triisobutylaluminum solution, and 10 g of butadiene were added sequentially to a 500 mL autoclave. Ethylene was then introduced at 0.8 MPa, and after saturation, a catalyst solution was added. Polymerization was carried out at room temperature (40 °C) for 180 minutes. After polymerization, the product was poured into a large amount of ethanol containing hydrochloric acid (2‰ by weight, hydrochloric acid is calculated as HCl), precipitated, and the copolymer was separated by filtration. After washing with ethanol, the copolymer was dried in a vacuum oven until its weight no longer decreased, yielding 9.20 g of copolymer. GPC analysis determined the number average molecular weight (M0.05) of the copolymer. n The molecular weight distribution index (M) is 116,500. w / M n The value is 2.1.

[0158] Nuclear magnetic resonance spectroscopy analysis determined that the molar content of butadiene structural units derived from butadiene in the prepared polymer was 72.6%; based on the total amount of butadiene structural units, the molar content of cis-1,4-structural units was 98.1%.

[0159] Comparative Example 1

[0160] Using the same method as in Example 1, except that the transition metal complex VI prepared in Comparative Example 1 was used instead of the complex shown in Formula II, 13.8 g of copolymer was obtained. GPC analysis determined that the number-average molecular weight (M) of this copolymer was... n The molecular weight distribution index (M) is 96,000. w / M n The value is 1.7.

[0161] Nuclear magnetic resonance spectroscopy analysis determined that the molar content of butadiene structural units derived from butadiene in the prepared copolymer was 82%; based on the total amount of butadiene structural units, the molar content of cis-1,4-structural units was 91.3%.

[0162] Example 8

[0163] In a glove box under an argon atmosphere, 22.24 mg of the complex shown in Formula III and 27.24 mg of N,N-dimethylphenylammonium tetra(pentafluorophenyl)borate were dissolved in 8 mL of toluene in a glass bottle to obtain a catalyst solution. In another glass bottle, 2 mL of 1 M triisobutylaluminum hexane solution and 7 mL of toluene were added to obtain a triisobutylaluminum solution.

[0164] 120 g of toluene, triisobutylaluminum solution, and 14 g of butadiene were added sequentially to a 500 mL autoclave. Ethylene was then introduced at 0.8 MPa, and after saturation, a catalyst solution was added. Polymerization was carried out at 40 °C for 60 minutes. After polymerization, the product was poured into a large amount of ethanol containing hydrochloric acid (2‰ by weight, hydrochloric acid is calculated as HCl), precipitated, and the copolymer was separated by filtration. After washing with ethanol, the copolymer was dried in a vacuum oven until its weight no longer decreased, yielding 8.70 g of copolymer. GPC analysis determined the number average molecular weight (Mn) of the copolymer. n The molecular weight distribution index (M) is 112000. w / M n The value is 2.5.

[0165] Nuclear magnetic resonance spectroscopy analysis determined that the molar content of butadiene structural units derived from butadiene in the prepared polymer was 65.3%; based on the total amount of butadiene structural units, the molar content of cis-1,4-structural units was 88.4%.

[0166] Comparative Example 2

[0167] This comparative example uses the coordination compound shown in Equation VII:

[0168]

[0169] In a glove box under an argon atmosphere, 17.50 mg of the complex shown in the formula and 27.24 mg of N,N-dimethylphenylammonium tetra(pentafluorophenyl)borate were dissolved in 8 mL of toluene in a glass bottle to obtain a catalyst solution. In another glass bottle, 2 mL of 1 M triisobutylaluminum hexane solution and 7 mL of toluene were added to obtain a triisobutylaluminum solution.

[0170] 120 g of toluene, triisobutylaluminum solution, and 14 g of butadiene were added sequentially to a 500 mL autoclave. Ethylene was then introduced at 0.8 MPa, and after saturation, a catalyst solution was added. Polymerization was carried out at 40 °C for 60 minutes. After polymerization, the product was poured into a large amount of ethanol containing hydrochloric acid (2‰ by weight, hydrochloric acid is calculated as HCl), precipitated, and the copolymer was separated by filtration. After washing with ethanol, the copolymer was dried in a vacuum oven until its weight no longer decreased, yielding 4.81 g of copolymer. GPC analysis determined the number average molecular weight (Mn) of the copolymer. n The molecular weight distribution index (M) is 105,000. w / M n The value is 2.3.

[0171] Nuclear magnetic resonance spectroscopy analysis determined that the molar content of butadiene structural units derived from butadiene in the prepared polymer was 71.5%; based on the total amount of butadiene structural units, the molar content of cis-1,4-structural units was 86.3%.

[0172] The experimental results of Examples 1-8 confirm that, according to the ethylene copolymer of the present invention, the content of ethylene structural units can vary within a relatively wide range, while maintaining a high degree of regularity of butadiene structural units and obtaining a high content of cis-1,4-structural units.

[0173] Comparing Example 1 with Comparative Example 1 and Example 8 with Comparative Example 2, it can be seen that under the same conditions, the polymerization method of the present invention can prepare more copolymers, indicating that the transition metal complex used in the polymerization method of the present invention has higher catalytic activity, thereby achieving higher polymerization reaction efficiency.

[0174] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. An ethylene copolymer comprising ethylene structural units derived from ethylene and conjugated diene structural units derived from a conjugated diene, the ethylene copolymer being formed by contacting ethylene and the conjugated diene with a transition metal complex of Formula I. In Formula I, Ln represents a lanthanide element, scandium, or yttrium; R1, R2, R3, R4, R5, R6, R7, R8, R9 and R 10 Whether the two are the same or different, they are each independently hydrogen, C1-C 20 Alkyl, C6-C 30 aryl or -SiR 23 R 24 R 25 R 23 R 24 and R 25 Whether they are the same or different, they are each independently hydrogen or C1-C 20 Alkyl groups; R 11 R 12 R 13 R 14 R 15 and R 16 Whether identical or different, each is independently hydrogen or a C1-C5 alkyl group; E is O, S, or NR 17 R 17 It is a C1-C5 alkyl group or a C6-C alkyl group. 12 Aryl groups.

2. The ethylene copolymer according to claim 1, wherein, In this ethylene copolymer, based on the total amount of ethylene copolymer, the content of ethylene structural units does not exceed 80 mol%.

3. The ethylene copolymer according to claim 1, wherein, In this ethylene copolymer, based on the total amount of ethylene copolymer, the content of ethylene structural units is 5-70 mol%.

4. The ethylene copolymer according to claim 1, wherein, In this ethylene copolymer, based on the total amount of ethylene copolymer, the content of ethylene structural units is 10-60 mol%.

5. The ethylene copolymer according to claim 1, wherein, In this ethylene copolymer, based on the total amount of structural units derived from conjugated dienes, the content of cis-1,4-structural units is 85 mol% or more.

6. The ethylene copolymer according to claim 1, wherein, In this ethylene copolymer, based on the total amount of structural units derived from conjugated dienes, the content of cis-1,4-structural units is 90 mol% or more.

7. The ethylene copolymer according to claim 1, wherein, In this ethylene copolymer, based on the total amount of structural units derived from conjugated dienes, the content of cis-1,4-structural units is 95 mol% or more.

8. The ethylene copolymer according to claim 1, wherein, In this ethylene copolymer, based on the total amount of structural units derived from conjugated dienes, the content of cis-1,4-structural units is 98 mol% or more.

9. The ethylene copolymer according to any one of claims 1-8, wherein, The conjugated diene is butadiene.

10. The ethylene copolymer according to any one of claims 1-8, wherein, The number average molecular weight of this ethylene copolymer ranges from 50,000 to 2 million.

11. The ethylene copolymer according to any one of claims 1-8, wherein, The number-average molecular weight of this ethylene copolymer ranges from 80,000 to 1.5 million.

12. The ethylene copolymer according to any one of claims 1-8, wherein, The molecular weight distribution index of this ethylene copolymer is 1.2-5.

13. The ethylene copolymer according to any one of claims 1-8, wherein, The molecular weight distribution index of this ethylene copolymer is 1.5-4.

14. The ethylene copolymer according to claim 1, wherein, In Formula I, R1 and R6 are each independently C1-C5 alkyl groups, and R2, R4, R7, and R9 are each independently C6-C5 alkyl groups. 12 Aryl groups, R3, R5, R8 and R 10 Both are hydrogen.

15. The ethylene copolymer according to claim 1, wherein, In Formula I, R1 and R6 are methyl groups, and R2, R4, R7 and R9 are phenyl groups.

16. The ethylene copolymer according to claim 1, wherein, In Equation I, R1, R4, R6, and R9 are each independently C1-C 20 The alkyl group, R2 and R7 are each independently C6-C. 30 Aryl groups, R3, R5, R8 and R 10 Both are hydrogen.

17. The ethylene copolymer according to claim 1, wherein, In Formula I, R1, R4, R6, and R9 are each independently a C1-C5 alkyl group, and R2 and R7 are each independently a C6-C5 alkyl group. 12 Aryl groups.

18. The ethylene copolymer according to claim 1, wherein, In Formula I, R1, R4, R6 and R9 are each independently methyl or isopropyl, and R2 and R7 are phenyl.

19. The ethylene copolymer according to claim 1, wherein, In Formula I, R1 and R6 are methyl, R4 and R9 are methyl or isopropyl, and R2 and R7 are phenyl.

20. The ethylene copolymer according to claim 1, wherein, In Equation I, R1, R4, R6, and R9 are each independently C1-C 20 The alkyl group, R2 and R7 are each independently C6-C. 30 Aryl, R5 and R 10 Both are hydrogen, and R3 and R8 are independently -SiR. 23 R 24 R 25 R 23 R 24 and R 25 Whether they are the same or different, each is independently C1-C 20 Alkyl groups.

21. The ethylene copolymer according to claim 1, wherein, In Formula I, R1, R4, R6, and R9 are each independently a C1-C5 alkyl group, and R2 and R7 are each independently a C6-C5 alkyl group. 12 The aryl group, R3 and R8, are each independently -SiR 23 R 24 R 25 R 23 R 24 and R 25 Whether the groups are the same or different, each is independently hydrogen or a C1-C5 alkyl group, and R 23 R 24 and R 25 At least one of them is a C1-C5 alkyl group.

22. The ethylene copolymer according to claim 1, wherein, In Formula I, R1, R4, R6, and R9 are methyl groups, R2 and R7 are phenyl groups, and R3 and R8 are each independently -SiR 23 R 24 R 25 R 23 R 24 and R 25 All are methyl groups.

23. The ethylene copolymer according to any one of claims 1 and 14-22, wherein, In Equation I, Ln represents scandium or gadolinium.

24. The ethylene copolymer according to claim 1, wherein, The transition metal complex is a complex shown in Formula II, Formula III, Formula IV, or Formula V.

25. A polymerization method comprising contacting ethylene and a conjugated diene with a transition metal complex of Formula I to obtain an ethylene copolymer containing ethylene structural units derived from ethylene and conjugated diene structural units derived from the conjugated diene. In Formula I, Ln represents a lanthanide element, scandium, or yttrium; R1, R2, R3, R4, R5, R6, R7, R8, R9 and R 10 Whether the two are the same or different, they are each independently hydrogen, C1-C 20 Alkyl, C6-C 30 aryl or -SiR 23 R 24 R 25 R 23 R 24 and R 25 Whether they are the same or different, they are each independently hydrogen or C1-C 20 Alkyl groups; R 11 R 12 R 13 R 14 R 15 and R 16 Whether identical or different, each is independently hydrogen or a C1-C5 alkyl group; E is O, S, or NR 17 R 17 It is a C1-C5 alkyl group or a C6-C alkyl group. 12 Aryl groups.

26. The method of claim 25, wherein, In Formula I, R1 and R6 are each independently C1-C5 alkyl groups, and R2, R4, R7, and R9 are each independently C6-C5 alkyl groups. 12 Aryl groups, R3, R5, R8 and R 10 Both are hydrogen.

27. The method according to claim 25, wherein, In Formula I, R1 and R6 are methyl groups, and R2, R4, R7 and R9 are phenyl groups.

28. The method according to claim 25, wherein, In Equation I, R1, R4, R6, and R9 are each independently C1-C 20 The alkyl group, R2 and R7 are each independently C6-C. 30 Aryl groups, R3, R5, R8 and R 10 Both are hydrogen.

29. The method according to claim 25, wherein, In Formula I, R1, R4, R6, and R9 are each independently a C1-C5 alkyl group, and R2 and R7 are each independently a C6-C5 alkyl group. 12 Aryl groups.

30. The method according to claim 25, wherein, In Formula I, R1, R4, R6 and R9 are each independently methyl or isopropyl, and R2 and R7 are phenyl.

31. The method according to claim 25, wherein, In Formula I, R1 and R6 are methyl, R4 and R9 are methyl or isopropyl, and R2 and R7 are phenyl.

32. The method according to claim 25, wherein, In Equation I, R1, R4, R6, and R9 are each independently C1-C 20 The alkyl group, R2 and R7 are each independently C6-C. 30 Aryl, R5 and R 10 Both are hydrogen, and R3 and R8 are independently -SiR. 23 R 24 R 25 R 23 R 24 and R 25 Whether they are the same or different, each is independently C1-C 20 Alkyl groups.

33. The method according to claim 25, wherein, In Formula I, R1, R4, R6, and R9 are each independently a C1-C5 alkyl group, and R2 and R7 are each independently a C6-C5 alkyl group. 12 The aryl group, R3 and R8, are each independently -SiR 23 R 24 R 25 R 23 R 24 and R 25 Whether the groups are the same or different, each is independently hydrogen or a C1-C5 alkyl group, and R 23 R 24 and R 25 At least one of them is a C1-C5 alkyl group.

34. The method according to claim 25, wherein, In Formula I, R1, R4, R6, and R9 are methyl groups, R2 and R7 are phenyl groups, and R3 and R8 are each independently -SiR 23 R 24 R 25 R 23 R 24 and R 25 All are methyl groups.

35. The method according to any one of claims 25-34, wherein, In Equation I, Ln represents scandium or gadolinium.

36. The method according to claim 25, wherein, The transition metal complex is a complex shown in Formula II, Formula III, Formula IV, or Formula V.

37. The method according to any one of claims 25-34 and 36, wherein, The contact takes place in the presence of a co-catalyst.

38. The method according to claim 37, wherein, The cocatalyst is an organoaluminum compound and / or an organoboron compound.

39. The method according to claim 38, wherein, The organoaluminum compound is an aluminum oxane and / or a compound represented by formula V. In formula V, R 17 R 18 and R 19 Whether the two are the same or different, they are each independently selected from hydrogen, C1-C 10 Alkyl, C1-C 10 alkoxy groups, C6-C 20 aryl, C7-C 15 alkylaryl, C7-C 15 Aryl groups and hydrogen atoms, and R 17 R 18 and R 19 They are not both hydrogen atoms.

40. The method of claim 38, wherein, The organoaluminum compound is triisobutylaluminum and / or diisobutylaluminum hydride.

41. The method according to claim 38, wherein, The organoboron compound is an organoborate.

42. The method according to claim 38, wherein, The organoboron compound is N,N-dimethylphenylammonium tetra(pentafluorophenyl)borate and / or triphenylmethyl-tetra(pentafluorophenyl)borate.

43. The method according to claim 38, wherein, The cocatalyst is an organoaluminum compound and an organoboron compound.

44. The method according to claim 43, wherein, The organoaluminum compound is triisobutylaluminum and / or diisobutylaluminum hydride.

45. The method according to claim 43, wherein, The organoboron compound is N,N-dimethylphenylammonium tetra(pentafluorophenyl)borate and / or triphenylmethyl-tetra(pentafluorophenyl)borate.

46. ​​The method according to claim 43, wherein, In the co-catalyst, the molar ratio of the organoaluminum compound to the organoboron compound is 1:0.01-100, wherein the organoaluminum compound is calculated as aluminum and the organoboron compound is calculated as boron.

47. The method according to claim 43, wherein, In the co-catalyst, the molar ratio of the organoaluminum compound to the organoboron compound is 1:0.1-90, wherein the organoaluminum compound is calculated as aluminum and the organoboron compound is calculated as boron.

48. The method according to claim 43, wherein, In the co-catalyst, the molar ratio of the organoaluminum compound to the organoboron compound is 1:0.5-60, wherein the organoaluminum compound is calculated as aluminum and the organoboron compound is calculated as boron.

49. The method according to claim 46, wherein, The molar ratio of the transition metal complex to the organoboron compound is 1:0.1-10.

50. The method of claim 46, wherein, The molar ratio of the transition metal complex to the organoboron compound is 1:0.5-5.

51. The method according to any one of claims 25-34 and 36, wherein, Based on the total amount of the ethylene copolymer, the content of ethylene structural units shall not exceed 80 mol%.

52. The method according to any one of claims 25-34 and 36, wherein, Based on the total amount of the ethylene copolymer, the content of ethylene structural units is 5-70 mol%.

53. The method according to any one of claims 25-34 and 36, wherein, Based on the total amount of the ethylene copolymer, the content of ethylene structural units is 10-60 mol%.

54. The method according to any one of claims 25-34 and 36, wherein, In the ethylene copolymer, based on the total amount of structural units derived from conjugated dienes, the content of cis-1,4-structural units is 85 mol% or more.

55. The method according to any one of claims 25-34 and 36, wherein, In the ethylene copolymer, based on the total amount of structural units derived from conjugated dienes, the content of cis-1,4-structural units is 90 mol% or more.

56. The method according to any one of claims 25-34 and 36, wherein, In the ethylene copolymer, based on the total amount of structural units derived from conjugated dienes, the content of cis-1,4-structural units is 95 mol% or more.

57. The method according to any one of claims 25-34 and 36, wherein, In the ethylene copolymer, based on the total amount of structural units derived from conjugated dienes, the content of cis-1,4-structural units is 98 mol% or more.

58. The method according to any one of claims 25-34 and 36, wherein, The conjugated diene is butadiene.

59. An ethylene copolymer prepared by the method of any one of claims 25-58.

Images