Rare earth complex with simple structure, catalyst composition and application

Abstract

The invention relates to a rare earth complex with a simple structure, a catalyst composition and application, and belongs to the technical field of polymer preparation. The structure of the rare earth complex is shown as a general formula (I), and in the general formula (I), Ln is Sc, Y, La, Pr, Nd, Gd, Tb, Dy, Ho, Er, Tm or Lu; in the formula (I), R1 is selected from halogen, silyl groups of C1 to C10, aralkyl groups of C7 to C15, silamido groups of C1 to C10 or allyl groups of C3 to C10; l is tetrahydrofuran, 2-methyltetrahydrofuran, tetrahydropyran, 1, 4-dioxane, ethylene glycol dimethyl ether, thiophane, tetramethylethylenediamine or pyridine; n = 0, 1 or 2. A catalytic polymerization system containing the rare earth complex provided by the invention has the following characteristics that the rare earth complex serving as a catalyst is simple in structure, convenient to prepare and high in polymerization yield, and a polymer prepared by catalyzing olefin has high stereoregularity. ; (I)

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of polymer preparation, in particular to a rare earth complex with simple structure, a catalyst composition and application. BACKGROUND

[0002] Polyolefins are a kind of high molecular materials with huge output and wide application. Stereoregularity is the guarantee of high performance of polyolefins, and is also necessary for these materials in many application occasions. Meanwhile, the macromolecular chains of these materials are mainly composed of C-C bonds with very low reactivity and non-polarity. The introduction of polar groups into the macromolecular chains can effectively improve the surface properties, adhesion, printing and dyeing properties, and can also improve the added value of these general-purpose materials. However, in the process of coordination polymerization, the oxygen, nitrogen, sulfur and other heteroatoms of polar olefins will preferentially coordinate with the central metal of the catalyst and form stable complexes, hindering the coordination-insertion of monomer double bond on the central metal, thereby leading to catalyst deactivation. The poisoning effect of polar olefins has always been a key problem restricting the development of functionalized polyolefins.

[0003] A series of reports show that the coordination polymerization method is the most direct and effective method for preparing functionalized polyolefins at present. By designing the ligand structure, the rate and selectivity of monomer coordination and insertion reaction can be influenced, making it possible for polar olefins to homopolymerize and copolymerize with other monomers. Through the design of polar olefin monomers and catalysts, Cui Dongmei's research group found that when the monomer coordinates with the central metal in σ-π mode, the coordination of the polar group is not poisoning but can activate the polymerization reaction. Taking the monomer of ortho-methoxyl substituted styrene as an example, although the β-diimine yttrium catalyst has no any polymerization activity for styrene, it can catalyze the polymerization of ortho-methoxyl styrene with high activity. In the polymerization process, the ortho-methoxyl styrene coordinates with the central metal through the methoxyl group and the double bond in σ-π mode, which reduces the coordination energy and insertion energy of the monomer on the central metal. Under the synergistic effect of the coordination of the polar group and the C 2v symmetry of the catalyst ligand geometry, a polymer with perfect isotacticity (mmmm > 99%) is obtained (Angew. Chem. Int. Ed. 2015, 54, 5205−5209). The polymer not only has a high melting point (302℃, which is nearly 70℃ higher than that of isotactic polystyrene), but also overcomes the slow crystallization rate of isotactic polystyrene, which expands the direction of its industrial application (Chinese invention patent, patent number: ZL201410401102.4). After that, the yttrium catalyst with C s symmetry of quinolinyl amine group can not only catalyze the "self-activation" polymerization of ortho-methoxyl styrene with high activity, but also the obtained polymer has perfect syndiotacticity (rrrr > 99%).

[0004] Functionalization and stereoregulation of polyolefins and its copolymers are the key problems in current coordination polymerization. The ligand structure is fine-tuned to the coordination polymerization process through electronic, stereoscopic, symmetry and other multi-dimensional factors, which is the core of designing high-performance catalysts and customizing polymer materials. For rare earth metal center, the structure of the ligand is complex, the synthesis process is cumbersome and the cost is high, which limits its application, no matter it is cyclopentadienyl ligand in metallocene catalyst or multi-dentate ligand (such as bipyridine, phenanthroline, etc.) or nitrogen heterocyclic carbene ligand (NHC) in non-metallocene catalyst. SUMMARY

[0005] The present application solves the technical problem that the structure of the rare earth metal complex catalyst is complex, the synthesis process is cumbersome and the cost is high, which limits its application in the prior art, and provides a rare earth complex and a catalyst composition with simple structure and application. The catalytic polymerization system containing the rare earth complex provided by the present application has the following characteristics: the structure of the rare earth complex as a catalyst is simple, the preparation is convenient, the polymerization yield is high, and the polymer prepared by catalyzing olefins has high stereoregularity.

[0006] In order to solve the above technical problems, the technical scheme of the present application is as follows:

[0007] A rare earth complex with simple structure, the structure of which is shown in general formula (I):

[0008] ; (I)

[0009] In general formula (I):

[0010] Ln is Sc, Y, La, Pr, Nd, Gd, Tb, Dy, Ho, Er, Tm or Lu;

[0011] R 1 is selected from halogen, borane, C1-C10 silane, C7-C15 aralkyl, C1-C10 silylamine or C3-C10 allyl;

[0012] L is tetrahydrofuran, 2-methyltetrahydrofuran, tetrahydropyran, 1,4-dioxane, ethylene glycol dimethyl ether, tetrahydrothiophene, tetramethyl ethylenediamine or pyridine;

[0013] n=0, 1 or 2.

[0014] In the above technical scheme, preferably, R 1 is selected from Cl, BH4, CH2SiMe3, o-NMe2-CH2C6H4, N(SiMe3)2, N(SiHMe2)2 or 1,3-C3H5.

[0015] In the technical scheme, preferably, the rare earth complex is selected from one of the structures shown in the following formulas 1-36:

[0016] ;

[0017] ;

[0018] ;

[0019] ;

[0020] ;

[0021] ;

[0022] ;

[0023] .

[0024] A catalyst composition, consisting of three parts of A, B and C;

[0025] A is the rare earth complex of the present application; B is an organic boron reagent; C is an aluminum-containing compound;

[0026] The molar ratio of the organic boron reagent to the rare earth complex is (0.5-2.0):1;

[0027] The molar ratio of the aluminum-containing compound to the rare earth complex is (0.5-3000):1.

[0028] In the technical scheme, preferably, B is one of [Ph3C][B(C6F5)4], [PhNMe2H][BPh4], [NEt3H][BPh4], [PhNMe2H][B(C6F5)4] or B(C6F5)3;

[0029] C represents trimethylaluminum, triethylaluminum, tri-n-propylaluminum, tri-n-butylaluminum, triisopropylaluminum, triisobutylaluminum, tripentylaluminum, trihexylaluminum, tricyclohexylaluminum, trioctylaluminum, triphenylaluminum, tri-p-tolylaluminum, tribenzylaluminum, ethyl dibenzylaluminum, ethyl di-p-tolylaluminum, diethylbenzylaluminum, dimethylaluminum hydride, diethylaluminum hydride, di-n-propylaluminum hydride, di-n-butylaluminum hydride, diisopropylaluminum hydride, diisobutylaluminum hydride, dipentylaluminum hydride, dihexylaluminum hydride, dicyclohexylaluminum hydride, dioctylaluminum hydride, diphenylaluminum hydride, and di-p-tolylaluminum hydride. One or more of the following: tolyl aluminum hydride, dibenzyl aluminum hydride, ethylbenzyl aluminum hydride, ethyl-p-tolyl aluminum hydride, dimethyl aluminum chloride, diethyl aluminum chloride, di-n-propyl aluminum chloride, di-n-butyl aluminum chloride, diisopropyl aluminum chloride, diisobutyl aluminum chloride, dipentyl aluminum chloride, dihexyl aluminum chloride, dicyclohexyl aluminum chloride, dioctyl aluminum chloride, diphenyl aluminum chloride, di-p-tolyl aluminum chloride, dibenzyl aluminum chloride, ethylbenzyl aluminum chloride, ethyl-p-tolyl aluminum chloride, methylaluminoxane, ethylaluminoxane, n-propylaluminoxane, and n-butylaluminoxane.

[0030] A method for catalytically highly selective polymerization of olefins includes the following steps:

[0031] a) Under the protection of inert gas nitrogen or argon, the catalyst composition of the present invention is dispersed in an organic solvent to obtain a rare earth catalyst solution;

[0032] b) Using olefins as monomer raw materials, the rare earth catalyst solution is used to catalyze the polymerization reaction. After a certain polymerization time, the polymerization reaction is terminated, the product is precipitated, and dried to obtain the polymer.

[0033] In the above technical solution, it is preferred that the olefin has a structure of general formula (II) or (III) or (IV);

[0034] ;

[0035] In general formula (II), R 1 The substituent on the benzene ring is hydrogen, a C1-C10 alkoxy group, a C6-C15 aryloxy group, a C1-C10 alkylthio group, or a C6-C15 arylthio group.

[0036] In general formula (Ⅲ), E represents O or S; R 2 The represents a substituent on the benzene ring, which can be hydrogen, a C1-C10 alkyl group, a C6-C15 aryl group, a C1-C10 alkyl group containing a halogen, or a halogen substituent; m represents the substituent R. 2 The number of elements is selected from integers from 1 to 5, and when m ≥ 2, R 2 Same or different;

[0037] In general formula (IV), R 3R represents a substituent on the double bond, and is hydrogen or C1-C6 alkyl.

[0038] In the above technical solution, further preferably, the olefin is one of the following structures:

[0039] ;

[0040] ;

[0041] ;

[0042] ;

[0043] ;

[0044] ;

[0045] .

[0046] In the above technical solution, preferably, the organic solvent is one or more of toluene, xylene, benzene, n-hexane, n-heptane, cyclohexane, chlorobenzene, dichlorobenzene and trichlorobenzene.

[0047] In the above technical solution, preferably, the molar ratio of the olefin to the rare earth complex having the structure of formula (I) in the catalyst composition is (50-10000):1.

[0048] The temperature of the polymerization reaction is -60-80℃, and the time is 0.5-200 hours.

[0049] The present application has the following beneficial effects:

[0050] The present application provides a rare earth complex with simple structure, a catalytic system composed of the rare earth complex, and a method for catalyzing high syndiotactic selectivity polymerization of olefins using the catalytic system. The catalytic system used in the present application is the rare earth complex with simple structure, an aluminum-containing compound (such as an alkyl aluminum compound) and an organic boron salt. The catalytic polymerization system containing the rare earth complex provided by the present application has the following characteristics: the rare earth complex as a catalyst has simple structure, is easy to prepare, and has high polymerization yield; and the polymer prepared by catalyzing olefins has high stereoregularity. The present application is the first to use a rare earth catalyst without complex ligand to synthesize polyolefins and oxygen-containing or sulfur-containing polar polyolefins, so the rare earth complex and the method for catalyzing high syndiotactic selectivity polymerization of olefins provided by the present application are very innovative. BRIEF DESCRIPTION OF DRAWINGS

[0051] The present application will be further described in detail below in combination with the drawings and specific embodiments.

[0052] Figure 1NMR spectrum of ethylene-hexene copolymer of application example 3 in table 2.

[0053] Figure 2 DSC curve of ethylene-(1-octene) copolymer of application example 7 in table 2.

[0054] Figure 3 Tensile curve of ethylene-(1-octene) copolymer of application example 7 in table 2.

[0055] Figure 4 NMR spectrum of typical rare earth complex formula 1 in general formula (I). DETAILED DESCRIPTION

[0056] The present application provides a rare earth complex with simple structure, which has the structure shown in general formula (I):

[0057] (I)

[0058] In general formula (I): Ln is Sc, Y, La, Pr, Nd, Gd, Tb, Dy, Ho, Er, Tm or Lu; R 1 is selected from halogen, borane group, C1-C10 silane group, C7-C15 aralkyl group, C1-C10 silylamine group or C3-C10 allyl group, preferably Cl, BH4, CH2SiMe3, o-NMe2-CH2C6H4, N(SiMe3)2, N(SiHMe2)2 or 1,3-C3H5; L is tetrahydrofuran, 2-methyltetrahydrofuran, tetrahydropyran, 1,4-dioxane, ethylene glycol dimethyl ether, tetrahydrothiophene, tetramethyl ethylenediamine or pyridine; n=0, 1 or 2. The polyolefin catalyzed by the rare earth complex provided by the present application also has the following characteristics: the number average molecular weight of the polyolefin is 1×10 4 ~ 250×10 4 , and the stereoselectivity of the polymer is not less than 90%.

[0059] Further preferably, the rare earth complex is selected from one of the following structures:

[0060] ;

[0061] ;

[0062] ;

[0063] ;

[0064] ;

[0065] ;

[0066] ;

[0067] .

[0068] The preparation method of the rare earth complex with simple structure as shown in the general formula (I) provided by the application is as follows:

[0069] In a glove box, a bottle is added with a chloride of Ln and a sufficient amount of L reagent (when n is 0, it represents that no L reagent is added), heated to reflux for 12 h, and then a solution of L of an alkyl lithium salt with a functional group of R 1 is added dropwise (if R 1 is halogen, no alkyl lithium salt needs to be added dropwise, and the corresponding solid complex is obtained after filtration; when n is 0, the alkyl lithium salt with a functional group of R 1 is directly added) after complexation, the solvent is dried after dropwise addition, extracted with n-hexane, the supernatant is collected, and the supernatant is poured into a container after standing at -30 o C to dry, and the solid powder of the rare earth complex as shown in the general formula (I) is obtained.

[0070] The application further provides a catalyst composition, which is a rare earth coordination catalytic system and is composed of three parts of A, B and C; A is the rare earth complex as shown in the formula (I) of the application; B is an organic boron reagent; and C is an aluminum-containing compound.

[0071] B is an organic boron reagent, which is selected from one of [Ph3C][B(C6F5)4], [PhNMe2H][BPh4], [NEt3H][BPh4], [PhNMe2H][B(C6F5)4] or B(C6F5)3, preferably [Ph3C][B(C6F5)4] or [PhNMe2H][B(C6F5)4];

[0072] The molar ratio of the organic boron reagent to the rare earth complex with the structure as shown in the formula (I) is (0.5-2.0):1;

[0073] C is an aluminum-containing compound, preferably an alkyl aluminum compound, a hydridoalkyl aluminum, a chloroalkyl aluminum, or an aluminoxane; further preferably one or more of trimethyl aluminum, triethyl aluminum, tri-n-propyl aluminum, tri-n-butyl aluminum, triisopropyl aluminum, triisobutyl aluminum, tripentyl aluminum, trihexyl aluminum, tricyclohexyl aluminum, trioctyl aluminum, triphenyl aluminum, tri-p-tolyl aluminum, tribenzyl aluminum, ethyldibenzyl aluminum, ethyldi-p-tolyl aluminum, diethylbenzyl aluminum, dimethylhydrido aluminum, diethylhydrido aluminum, di-n-propylhydrido aluminum, di-n-butylhydrido aluminum, diisopropylhydrido aluminum, diisobutylhydrido aluminum, dipentylhydrido aluminum, dihexylhydrido aluminum, dicyclohexylhydrido aluminum, dioctylhydrido aluminum, diphenylhydrido aluminum, di-p-tolylhydrido aluminum, dibenzylhydrido aluminum, ethylbenzylhydrido aluminum, ethyl-p-tolylhydrido aluminum, dimethylchloro aluminum, diethylchloro aluminum, di-n-propylchloro aluminum, di-n-butylchloro aluminum, diisopropylchloro aluminum, diisobutylchloro aluminum, dipentylchloro aluminum, dihexylchloro aluminum, dicyclohexylchloro aluminum, dioctylchloro aluminum, diphenylchloro aluminum, di-p-tolylchloro aluminum, dibenzylchloro aluminum, ethylbenzylchloro aluminum, ethyl-p-tolylchloro aluminum, methylaluminoxane, ethylaluminoxane, n-propylaluminoxane, and n-butylaluminoxane.

[0074] The molar ratio of the aluminum-containing compound to the rare earth complex having the structure of formula (I) is (0.5-3000):1.

[0075] The present application also provides a method for catalyzing high-selectivity polymerization of olefins, comprising the following steps:

[0076] a) dispersing the catalyst composition of the present application in an organic solvent under the protection of inert gas nitrogen or argon to obtain a rare earth catalyst solution;

[0077] b) using the rare earth catalyst solution to catalyze polymerization reaction according to a certain monomer feeding ratio with olefins as monomer raw materials, stopping the polymerization reaction after a certain polymerization time, and obtaining polyolefin by settling and drying the product. The polymerization reaction can be carried out in solution polymerization with solvent or in bulk polymerization without solvent.

[0078] wherein the olefins have the structure of general formula (II) or (III) or (IV);

[0079] ;

[0080] In general formula (II), R 1 represents a substituent on the benzene ring, which is hydrogen, C1-C10 alkoxy, C6-C15 aryloxy, C1-C10 alkylthio, or C6-C15 arylthio. In general formula (III), E represents O or S; R 2R represents a substituent on the benzene ring, and is hydrogen, C1-C10 alkyl, C6-C15 aryl, C1-C10 halogen-containing alkyl, or a halogen substituent; m represents the number of substituents R 2 , and is an integer from 1 to 5, and when m≥2, R 2 are the same or different. In general formula (IV), R 3 represents a substituent on the double bond, and is hydrogen or C1-C6 alkyl.

[0081] It is further preferred that the olefin is one of the structures shown in 1-32:

[0082] ;

[0083] ;

[0084] ;

[0085] ;

[0086] ;

[0087] ;

[0088] .

[0089] When solution polymerization is used, the organic solvent is selected from one or a mixture of several of saturated alkanes, aromatic hydrocarbons, halogenated aromatic hydrocarbons, and cycloalkanes. Preferably, one or several of toluene, xylene, benzene, n-hexane, n-heptane, cyclohexane, chlorobenzene, dichlorobenzene, and trichlorobenzene are used.

[0090] The molar ratio of the monomer of the olefin to the rare earth complex having the structure of formula (I) is (50-10000):1.

[0091] The temperature of the polymerization reaction is -60-80°C, and the time of the polymerization reaction is 0.5-200 hours.

[0092] According to the present application, the preparation method of the catalyst composition is as follows: the rare earth complex having the structure of formula (I), the aluminum-containing compound (such as an alkyl aluminum compound), and the organic boron reagent are mixed in an organic solvent according to the ratio to obtain a homogeneous catalyst. The organic solvent is selected from one or a mixture of several of saturated alkanes, aromatic hydrocarbons, halogenated aromatic hydrocarbons, and cycloalkanes. Preferably, one or several of toluene, xylene, benzene, n-hexane, n-heptane, cyclohexane, chlorobenzene, dichlorobenzene, and trichlorobenzene are used.

[0093] The present application provides a method for catalyzing high-selectivity polymerization of olefins, and a specific embodiment is as follows:

[0094] The solution of the coordination catalytic system of the rare earth complex, the aluminum-containing compound (such as an alkyl aluminum compound) and the organic boron reagent is placed in a polymerization container treated with anhydrous and oxygen-free; meanwhile, an olefin monomer is added, and the molar ratio of the added olefin monomer to the rare earth complex in the coordination catalytic system of the solution of the rare earth catalyst is 50:1-10000:1, the polymerization reaction is carried out at-60-80 ℃ for 0.5-200 hours, the polymerization reaction is terminated by adding an ethanol solution of hydrochloric acid with a volume concentration of 10%, the reaction solution is poured into methanol for sedimentation, and a syndiotactic polyolefin is obtained; then the obtained polymer is placed in a vacuum drying box for drying, and a dried constant-weight polymer is obtained.

[0095] In order to further understand the present application, the preferred embodiments of the present application are described below in conjunction with examples, but it should be understood that these descriptions are only for further illustrating the features and advantages of the present application and are not limitations on the claims of the present application. The following are specific examples of the present application, and it should be noted that the schemes to be protected by the present application are not limited to the following examples.

[0096] Preparation of the rare earth complex:

[0097] The preparation method of the rare earth complex of formula 1 is as follows:

[0098] In a glove box, 10 mmol of scandium trichloride and 100 mL of tetrahydrofuran are added to a bottle, heated to reflux for 12 h, and then 29 mmol of tetramethylsilyl lithium in tetrahydrofuran is added dropwise. After the dropwise addition is completed, the solvent is dried, extracted with n-hexane, and the upper clear liquid is collected. After standing at-30 o C for 2 h, the upper clear liquid is poured into a container and dried, and a white solid powder is obtained, which is the rare earth complex of formula 1. The hydrogen nuclear magnetic resonance spectrum is shown in Figure 4 .

[0099] The rare earth complexes of formula 2-formula 36 are all prepared by referring to the above method, which will not be exemplified one by one here.

[0100] Preparation of a catalyst composition (hereinafter referred to as a catalyst combination):

[0101] Preparation of catalyst combination 1: 10 μmol of the rare earth complex of formula 1, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutyl aluminum and 5 mL of toluene solvent are added to a 25 mL polymerization container treated with anhydrous and oxygen-free and protected by inert nitrogen gas at 25 ℃, and the concentration of the rare earth complex in the catalyst combination is 2.0 mmol·L –1 , and the reaction is carried out for 2 minutes to obtain catalyst combination 1.

[0102] Preparation of catalyst combination 2: 25 mL of a polymerization vessel treated with anhydrous, oxygen-free and protected by inert gas nitrogen was charged with 10 μmol of the rare earth complex shown in formula 2, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 15 mL of toluene solvent at 25 ℃, the concentration of the rare earth complex in the catalyst combination was 0.67 mmol·L –1 , and reacted for 2 minutes to obtain catalyst combination 2.

[0103] Preparation of catalyst combination 3: 100 mL of a polymerization vessel treated with anhydrous, oxygen-free and protected by inert gas nitrogen was charged with 15 μmol of the rare earth complex shown in formula 2, 15 μmol of [Ph3C][B(C6F5)4], 300 μmol of triisobutylaluminum and 15 mL of toluene solvent at 40 ℃, the concentration of the rare earth complex in the catalyst combination was 1.0 mmol·L –1 , and reacted for 2 minutes to obtain catalyst combination 3.

[0104] Preparation of catalyst combination 4: 25 mL of a polymerization vessel treated with anhydrous, oxygen-free and protected by inert gas nitrogen was charged with 10 μmol of the rare earth complex shown in formula 2, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 15 mL of toluene solvent at 0 ℃, the concentration of the rare earth complex in the catalyst combination was 0.67 mmol·L –1 , and reacted for 2 minutes to obtain catalyst combination 4.

[0105] Preparation of catalyst combination 5: 25 mL of a polymerization vessel treated with anhydrous, oxygen-free and protected by inert gas nitrogen was charged with 10 μmol of the rare earth complex shown in formula 2, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 15 mL of toluene solvent at -60 ℃, the concentration of the rare earth complex in the catalyst combination was 0.67 mmol·L –1 , and reacted for 2 minutes to obtain catalyst combination 5.

[0106] Preparation of catalyst combination 6: 25 mL of a polymerization vessel treated with anhydrous, oxygen-free and protected by inert gas nitrogen was charged with 10 μmol of the rare earth complex shown in formula 2, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 15 mL of toluene solvent at 40 ℃, the concentration of the rare earth complex in the catalyst combination was 0.67 mmol·L –1 , and reacted for 2 minutes to obtain catalyst combination 6.

[0107] Preparation of catalyst combination 7: 10 μmol of the rare earth complex shown in formula 2, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 15 mL of toluene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 80 ℃, the concentration of the rare earth complex in the catalyst combination was 0.67 mmol·L –1 , and reacted for 2 minutes to obtain catalyst combination 7.

[0108] Preparation of catalyst combination 8: 10 μmol of the rare earth complex shown in formula 3, 10 μmol of [PhNHMe2][B(C6F5)4], 200 μmol of triethylaluminum and 10 mL of hexane solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 25 ℃, the concentration of the rare earth complex in the catalyst combination was 1.0 mmol·L –1 , and reacted for 2 minutes to obtain catalyst combination 8.

[0109] Preparation of catalyst combination 9: 10 μmol of the rare earth complex shown in formula 4, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 10 mL of toluene solvent were added into a 50 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at -40 ℃, the concentration of the rare earth complex in the catalyst combination was 1.0 mmol·L –1 , and reacted for 2 minutes to obtain catalyst combination 9.

[0110] Preparation of catalyst combination 10: 10 μmol of the rare earth complex shown in formula 5, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 20 mL of pentane solvent were added into a 50 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 25 ℃, the concentration of the rare earth complex in the catalyst combination was 0.5 mmol·L –1 , and reacted for 2 minutes to obtain catalyst combination 10.

[0111] Preparation of catalyst combination 11: 10 μmol of the rare earth complex shown in formula 6, 10 μmol of [PhNHMe2][B(C6F5)4], 1 mmol of triisobutylaluminum and 10 mL of xylene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 60 ℃, the concentration of the rare earth complex in the catalyst combination was 1.0 mmol·L –1 , and reacted for 2 minutes to obtain catalyst combination 11.

[0112] Preparation of catalyst combination 12: 10 μmol of the rare earth complex shown in formula 7, 10 μmol of [Ph3C][BPh4], 10 mmol of triisobutylaluminum and 50 mL of hexane solvent were added into a 100 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 25 °C, the concentration of the rare earth complex in the catalyst combination was 0.2 mmol·L –1 , and reacted for 2 minutes to obtain catalyst combination 12.

[0113] Preparation of catalyst combination 13: 10 μmol of the rare earth complex shown in formula 8, 20 μmol of [PhNHMe2][BPh4], 5 mmol of triisobutylaluminum and 40 mL of hexane solvent were added into a 100 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 0 °C, the concentration of the rare earth complex in the catalyst combination was 0.25 mmol·L –1 , and reacted for 2 minutes to obtain catalyst combination 13.

[0114] Preparation of catalyst combination 14: 10 μmol of the rare earth complex shown in formula 9, 10 μmol of B(C6F5)3, 100 μmol of triisobutylaluminum and 50 mL of hexane solvent were added into a 100 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 80 °C, the concentration of the rare earth complex in the catalyst combination was 0.2 mmol·L –1 , and reacted for 2 minutes to obtain catalyst combination 14.

[0115] Preparation of catalyst combination 15: 10 μmol of the rare earth complex shown in formula 10, 10 μmol of [Ph3C][B(C6F5)4], 500 μmol of triisobutylaluminum and 40 mL of xylene solvent were added into a 100 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 0 °C, the concentration of the rare earth complex in the catalyst combination was 0.25 mmol·L –1 , and reacted for 2 minutes to obtain catalyst combination 15.

[0116] Preparation of catalyst combination 16: 10 μmol of the rare earth complex shown in formula 11, 10 μmol of [PhNHMe2][B(C6F5)4], 100 μmol of trimethylaluminum and 30 mL of toluene solvent were added into a 50 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 40 °C, the concentration of the rare earth complex in the catalyst combination was 0.33 mmol·L –1 , and reacted for 2 minutes to obtain catalyst combination 16.

[0117] Preparation of catalyst combination 17: 10 μmol of the rare earth complex shown in formula 12, 10 μmol of [NEt3H][BPh4], 100 μmol of trimethylaluminum and 40 mL of a toluene solvent were added into a 100 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 25 °C, the concentration of the rare earth complex in the catalyst combination was 0.25 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 17.

[0118] Preparation of catalyst combination 18: 10 μmol of the rare earth complex shown in formula 13, 10 μmol of [Ph3C][BPh4], 100 μmol of triisobutylaluminum and 40 mL of a hexane solvent were added into a 100 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at -60 °C, the concentration of the rare earth complex in the catalyst combination was 0.25 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 18.

[0119] Preparation of catalyst combination 19: 10 μmol of the rare earth complex shown in formula 14, 10 μmol of [Ph3C][BPh4], 30 mmol of methylaluminoxane and 50 mL of a toluene solvent were added into a 100 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 80 °C, the concentration of the rare earth complex in the catalyst combination was 0.2 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 19.

[0120] Preparation of catalyst combination 20: 10 μmol of the rare earth complex shown in formula 15, 10 μmol of [Ph3C][B(C6F5)4], 20 μmol of diisobutylaluminum hydride and 50 mL of a chlorobenzene solvent were added into a 100 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 0 °C, the concentration of the rare earth complex in the catalyst combination was 0.2 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 20.

[0121] Preparation of catalyst combination 21: 10 μmol of the rare earth complex shown in formula 15, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of methylaluminoxane and 50 mL of a chlorobenzene solvent were added into a 100 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 25 °C, the concentration of the rare earth complex in the catalyst combination was 0.2 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 21.

[0122] Preparation of catalyst combination 22: 10 μmol of the rare earth complex shown in formula 13, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 5 mL of toluene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 25 °C, the concentration of the rare earth complex in the catalyst combination was 2.0 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 22.

[0123] Preparation of catalyst combination 23: 10 μmol of the rare earth complex shown in formula 14, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 5 mL of toluene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 25 °C, the concentration of the rare earth complex in the catalyst combination was 2.0 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 23.

[0124] Preparation of catalyst combination 24: 10 μmol of the rare earth complex shown in formula 16, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 5 mL of toluene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 25 °C, the concentration of the rare earth complex in the catalyst combination was 2.0 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 24.

[0125] Preparation of catalyst combination 25: 10 μmol of the rare earth complex shown in formula 17, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 5 mL of toluene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 25 °C, the concentration of the rare earth complex in the catalyst combination was 2.0 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 25.

[0126] Preparation of catalyst combination 26: 10 μmol of the rare earth complex shown in formula 19, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 5 mL of toluene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas nitrogen at 25 °C, the concentration of the rare earth complex in the catalyst combination was 2.0 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 26.

[0127] Preparation of catalyst combination 27: 10 μmol of the rare earth complex shown in formula 20, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 5 mL of toluene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas argon at 25 °C, the concentration of the rare earth complex in the catalyst combination was 2.0 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 27.

[0128] Preparation of catalyst combination 28: 10 μmol of the rare earth complex shown in formula 22, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 5 mL of toluene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas argon at 25 °C, the concentration of the rare earth complex in the catalyst combination was 2.0 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 28.

[0129] Preparation of catalyst combination 29: 10 μmol of the rare earth complex shown in formula 23, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 5 mL of toluene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas argon at 25 °C, the concentration of the rare earth complex in the catalyst combination was 2.0 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 29.

[0130] Preparation of catalyst combination 30: 10 μmol of the rare earth complex shown in formula 25, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 5 mL of toluene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas argon at 25 °C, the concentration of the rare earth complex in the catalyst combination was 2.0 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 30.

[0131] Preparation of catalyst combination 31: 10 μmol of the rare earth complex shown in formula 26, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 5 mL of toluene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas argon at 25 °C, the concentration of the rare earth complex in the catalyst combination was 2.0 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 31.

[0132] Preparation of catalyst combination 32: 10 μmol of the rare earth complex shown in formula 28, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 5 mL of toluene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas argon at 25 °C, the concentration of the rare earth complex in the catalyst combination was 2.0 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 32.

[0133] Preparation of catalyst combination 33: 10 μmol of the rare earth complex shown in formula 29, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 5 mL of toluene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas argon at 25 °C, the concentration of the rare earth complex in the catalyst combination was 2.0 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 33.

[0134] Preparation of catalyst combination 34: 10 μmol of the rare earth complex shown in formula 31, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 5 mL of toluene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas argon at 25 °C, the concentration of the rare earth complex in the catalyst combination was 2.0 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 34.

[0135] Preparation of catalyst combination 35: 10 μmol of the rare earth complex shown in formula 34, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 5 mL of toluene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas argon at 25 °C, the concentration of the rare earth complex in the catalyst combination was 2.0 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 35.

[0136] Preparation of catalyst combination 36: 10 μmol of the rare earth complex shown in formula 35, 10 μmol of [Ph3C][B(C6F5)4], 100 μmol of triisobutylaluminum and 5 mL of toluene solvent were added into a 25 mL polymerization vessel treated by anhydrous, anaerobic treatment and protected by inert gas argon at 25 °C, the concentration of the rare earth complex in the catalyst combination was 2.0 mmol·L –1 , reacted for 2 minutes to obtain catalyst combination 36.

[0137] Olefin polymerization example:

[0138] Example 1

[0139] Take 5 mL of toluene solution of catalyst combination 1 and place it in a polymerization flask that has been treated with anhydrous and oxygen-free conditions and protected with an inert gas. Add 5.0 mmol of styrene monomer as shown in Formula 1. The polymerization reaction is carried out at 25 °C for 4 hours. The polymerization reaction is terminated by adding 2 mL of ethanol solution with a volume concentration of 10% hydrochloric acid. Pour the reaction solution into 100 mL of methanol to precipitate, and obtain syndiotactic selective polystyrene. Then place the obtained polymer in a vacuum drying oven and dry for 48 hours to obtain polystyrene with constant weight and a net weight of 0.52 g. The total conversion rate is 100%. ¹H NMR spectroscopy (NMR) was used to analyze the results. 1 H NMR) and carbon NMR ( 13 ¹³C NMR analysis showed that the syndiotacticity of polystyrene was greater than 99%; GPC analysis showed that the number-average molecular weight (Mn) of polystyrene was... n The value is 80,000, and the molecular weight distribution (M) is... w / M n The glass transition temperature (Tg) of polystyrene was 1.48. DSC analysis yielded the glass transition temperature (Tg) of polystyrene. g ) is 7 o C

[0140] Example 2–50

[0141] Examples of the coordination catalytic system provided by the present invention in olefin polymerization are presented. The steps are the same as in Example 1, and the specific conditions and results are shown in Table 1.

[0142] Table 1. Synthesis of polyolefins with high structural selectivity using coordination polymerization methods.

[0143]

[0144] Continued from Table 1: Synthesis of structurally selective polyolefins via coordination polymerization

[0145]

[0146] Continued from Table 1: Synthesis of structurally selective polyolefins via coordination polymerization

[0147]

[0148] Continued from Table 1: Synthesis of structurally selective polyolefins via coordination polymerization

[0149]

[0150] Table 2. Synthesis of polyethylene and ethylene-α-olefin copolymers by coordination polymerization method.

[0151]

[0152] From the polymerization data of Examples 2~48 of olefin polymerization in Table 1, it can be concluded that the rare earth catalyst combination provided by the present application can achieve 100% conversion of olefin monomers when catalyzing the polymerization of olefin by coordination polymerization. The number average molecular weight of the polyolefin is in the range of 1x10 4 4 The molecular weight distribution is 1.1~3.0. The rare earth catalyst combination has high adaptability to temperature, and the syndiotactic selectivity (rrrr) of the polyolefin is not less than 90% in the polymerization temperature range of -20~80 ℃.

[0153] From the polymerization data of Examples 1~9 in Table 2, it can be concluded that the rare earth catalyst combination provided by the present application can achieve fast conversion of ethylene monomers when catalyzing the polymerization of olefin by coordination polymerization. With the increase of the feeding ratio of copolymerization α-olefin, its proportion in the copolymer also gradually increases.

[0154] Figure 1 The nuclear magnetic resonance spectrum of the ethylene-hexene copolymer of application example 3 in Table 2, Figure 1 can prove the successful synthesis of the ethylene-hexene copolymer.

[0155] Figure 2 The DSC curve of the ethylene-(1-octene) copolymer of application example 7 in Table 2, Figure 2 can be known that the melting temperature of the copolymer is about 129 o C.

[0156] Figure 3 The tensile curve of the ethylene-(1-octene) copolymer of application example 7 in Table 2, Figure 3 can be known that the yield strength of the copolymer is about 32.5 MPa, the tensile strength is about 30 MPa, and the elongation at break is about 700%.

[0157] Obviously, the above examples are only examples for clearly illustrating, but not limitation of the embodiments. For those skilled in the art, other different forms of changes or variations can be made on the basis of the above description. Here, it is not necessary and impossible to exhaust all the embodiments. The obvious changes or variations derived therefrom are still within the protection scope of the present application.​

Claims

1. A rare earth complex with a simple structure, characterized in that, Its structure is shown in general formula (Ⅰ): ；（Ⅰ） In general formula (Ⅰ): Ln is Sc, Y, La, Pr, Nd, Gd, Tb, Dy, Ho, Er, Tm or Lu; R 1 Selected from halogens, boranes, C1-C10 silanes, C7-C15 aralkyls, C1-C10 silamidos, or C3-C10 allyls; L is tetrahydrofuran, 2-methyltetrahydrofuran, tetrahydropyran, 1,4-dioxane, ethylene glycol dimethyl ether, tetrahydrothiophene, tetramethylethylenediamine, or pyridine; n = 0, 1, or 2.

2. The rare earth complex according to claim 1, characterized in that, R 1 Selected from Cl, BH4, CH2SiMe3, o-NMe2-CH2C6H4, N(SiMe3)2, N(SiHMe2)2 or 1,3-C3H5.

3. The rare earth complex according to claim 1, characterized in that, It is selected from one of the structures shown in Equation 1-36: ； ； ； ； ； ； ； 。 4. A catalyst composition, characterized in that, It consists of three parts: A, B, and C. A is the rare earth complex according to any one of claims 1-3; B is an organoboron reagent; C is an aluminum-containing compound; The molar ratio of the organoboron reagent to the rare earth complex is (0.5~2.0):1; The molar ratio of the aluminum-containing compound to the rare earth complex is (0.5~3000):

1.

5. The catalyst composition according to claim 4, characterized in that, B is one of [Ph3C][B(C6F5)4], [PhNMe2H][BPh4], [NEt3H][BPh4], [PhNMe2H][B(C6F5)4], or B(C6F5)3; C represents trimethylaluminum, triethylaluminum, tri-n-propylaluminum, tri-n-butylaluminum, triisopropylaluminum, triisobutylaluminum, tripentylaluminum, trihexylaluminum, tricyclohexylaluminum, trioctylaluminum, triphenylaluminum, tri-p-tolylaluminum, tribenzylaluminum, ethyl dibenzylaluminum, ethyl di-p-tolylaluminum, diethylbenzylaluminum, dimethylaluminum hydride, diethylaluminum hydride, di-n-propylaluminum hydride, di-n-butylaluminum hydride, diisopropylaluminum hydride, diisobutylaluminum hydride, dipentylaluminum hydride, dihexylaluminum hydride, dicyclohexylaluminum hydride, dioctylaluminum hydride, diphenylaluminum hydride, and di-p-tolylaluminum hydride. One or more of the following: tolyl aluminum hydride, dibenzyl aluminum hydride, ethylbenzyl aluminum hydride, ethyl-p-tolyl aluminum hydride, dimethyl aluminum chloride, diethyl aluminum chloride, di-n-propyl aluminum chloride, di-n-butyl aluminum chloride, diisopropyl aluminum chloride, diisobutyl aluminum chloride, dipentyl aluminum chloride, dihexyl aluminum chloride, dicyclohexyl aluminum chloride, dioctyl aluminum chloride, diphenyl aluminum chloride, di-p-tolyl aluminum chloride, dibenzyl aluminum chloride, ethylbenzyl aluminum chloride, ethyl-p-tolyl aluminum chloride, methylaluminoxane, ethylaluminoxane, n-propylaluminoxane, and n-butylaluminoxane.

6. A method for catalyzing highly selective polymerization of olefins, characterized in that, Includes the following steps: a) Under the protection of inert gas nitrogen or argon, the catalyst composition of claim 4 is dispersed in an organic solvent to obtain a rare earth catalyst solution; b) Using olefins as monomer raw materials, the rare earth catalyst solution is used to catalyze the polymerization reaction. After a certain polymerization time, the polymerization reaction is terminated, the product is precipitated, and dried to obtain the polymer.

7. The method according to claim 6, characterized in that, The olefin has a structure of general formula (II) or (III) or (IV); ； In general formula (II), R 1 The substituent on the benzene ring is hydrogen, a C1-C10 alkoxy group, a C6-C15 aryloxy group, a C1-C10 alkylthio group, or a C6-C15 arylthio group. In general formula (Ⅲ), E represents O or S; R 2 The represents a substituent on the benzene ring, which can be hydrogen, a C1-C10 alkyl group, a C6-C15 aryl group, a C1-C10 alkyl group containing a halogen, or a halogen substituent; m represents the substituent R. 2 The number of elements is selected from integers from 1 to 5, and when m ≥ 2, R 2 Same or different; In general formula (IV), R 3 This indicates a substituent on the double bond, which is either hydrogen or a C1-C6 alkyl group.

8. The method according to claim 7, characterized in that, The olefin is one of the following structures: ； ； ； ； ； ； 。 9. The method according to claim 6, characterized in that, The organic solvent is one or more of toluene, xylene, benzene, n-hexane, n-heptane, cyclohexane, chlorobenzene, dichlorobenzene, and trichlorobenzene.

10. The method according to claim 6, characterized in that, The molar ratio of the olefin to the rare earth complex having the structure of formula (Ⅰ) in the catalyst composition is (50~10000):1; The polymerization reaction is carried out at temperatures ranging from -60 to 80°C for 0.5 to 200 hours.

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