Method for preparing polyolefin through cascade polymerization

Abstract

A method for preparing polyolefin through cascade polymerization comprises the following steps: (1) under anhydrous and anaerobic conditions, in the presence of a COF-supported oligomerization catalyst or a COF-supported homopolymerization catalyst and an optional cocatalyst, ethylene and / or propylene monomers are subjected to an oligomerization reaction in a non-polar organic solvent, and a product is obtained; respectively obtaining an oligomerization product or a macromonomer with terminal double bonds; and (2) then, carrying out further polymerization reaction on the oligomerization product or the macromonomer with terminal double bonds and an olefin monomer in a non-polar organic solvent in the presence of an olefin polymerization catalyst under anhydrous and anaerobic conditions to obtain polyolefin.

Description

A method for preparing polyolefins by cascade polymerization Technical Field

[0001] The present invention relates to a method for preparing polyolefins by cascade polymerization, which comprises using a COF-supported oligomerization or homopolymerization catalyst. Background Art

[0002] Polyolefins are one of the most important synthetic materials, accounting for 60% of total synthetic resin production. Therefore, the development of the polyolefin industry directly impacts the national economy. The quality of polyolefin products is primarily determined by the polymerization technology and processes used. Cascade polymerization is a polymerization reaction that simultaneously utilizes two or more catalyst systems capable of catalyzing different reactions. This process offers advantages such as eliminating the need for intermediate separation, storage, and transportation, and providing convenience and efficiency. However, the simultaneous use of two catalysts in a cascade polymerization process can lead to mutual interference, which is directly reflected in changes in polymerization activity and copolymer molecular weight.

[0003] Covalent organic frameworks (COFs) are a class of porous two- or three-dimensional polymer materials with periodic structures connected by covalent bonds. Their pore size and framework structure can be precisely controlled through monomers and linkers. The uniform and tunable pore structure of COFs provides a uniform and stable chemical environment for supported catalysts, facilitating precise control of catalytic performance.

[0004] Therefore, if COF-supported oligomerization or homopolymerization catalysts can be used to reduce the mutual influence between the oligomerization or homopolymerization catalyst and the copolymerization catalyst in the cascade polymerization, it will be beneficial to develop a method for efficiently preparing high-performance thermoplastic polyolefin products through cascade polymerization.

[0005] Summary of the Invention

[0006] In a first aspect, the present invention provides a method for preparing polyolefins by cascade polymerization, comprising the steps of:

[0007] (1) oligomerizing ethylene and / or propylene monomers in a non-polar organic solvent in the presence of a COF-supported oligomerization catalyst or a COF-supported homopolymerization catalyst and an optional co-catalyst under anhydrous and oxygen-free conditions to obtain an oligomerization product or a macromonomer with a terminal double bond, respectively; and

[0008] (2) Then, the oligomerization product or the macromonomer with a terminal double bond is further polymerized with an olefin monomer in a non-polar organic solvent in the presence of an olefin polymerization catalyst under anhydrous and oxygen-free conditions to obtain a polyolefin.

[0009] In the above method, the anhydrous and anaerobic conditions refer to the absence of water in the reaction, and the anaerobic conditions are obtained by replacing the oxygen in the reactor with an inert gas such as nitrogen, argon, helium and supercritical carbon dioxide and then evacuating the reactor.

[0010] The COF-supported oligomerization catalyst includes metallocene catalysts and post-metallocene catalysts known in the art as being useful as oligomerization catalysts, particularly metallocene catalysts and post-metallocene catalysts wherein the metal is selected from chromium, nickel, thallium, hafnium, titanium, vanadium, zirconium, and molybdenum, preferably selected from chromium and nickel. Examples of the metallocene catalyst include, for example, 1,2,3,4,5-Ph5-Cp / Cr(EH)3, {2-[1-(3H-Ind)CyH]Th}TiCl3, and decamethyl-bis(cyclopentadiene)zirconium dichloride. Examples of the post-metallocene catalyst include, for example, Ar2PN(Me)PAr2 / Cr, {HN(CH2CH2PPh2)2}CrCl3, Cr(EH)3 / 2,5-DMP, [(2-Pe-S-Et)2-A]CrCl3, DPPB / [Cr(H2O)4Cl2]Cl·2H2O, SNS-Cr, NiCl2{[2-(5-Ph-Pyz)Et]2E}, NiCl2{[2-(3,5-Me2Pyz)Me]2BuA}, Mo(μ-N-Bu t AlCl2)2, NiBr2{[2-(3,5-Me2Pyz)]EtA}, V(NAd)Cl2[8-(2,6-Me2An)-5,6,7-H3Qu], N iBr2[(3,5-Me2Pyz)2PhP], WCl6 / 2DippNH2 / 4NEt3, TaCl3(NDipp)(tmeda), Nb(N-2,6- Ph)Me2[2-(2,6-Me2Ph)NCH2(Pyd)], Ti(OBu n )4, NiCl2(Bu n 3P)2,Cr(acac)3 / Ph2P)2NPr i ,Cr(acac)3 / [(oF-CH)(o-MeOCH)P]2N(Pr i ), Cr(CO)4[(Ph2P)2NPr j ], [(DPPDME)CrCl3]2, CrCl2(THF)2 / Ph2PN(Me)(CH2)3N(Me)PPh2, Cr(SBDP)Cl3, [2-CrCl2] + [B(C6F5)4] -, Cr(acac)3 / Ph2PN(But)PPh2, PNP / CrCl3(THF)3 and Cr(CO)6 / Ph2PN(Pr j )Si(CH3)2CH2Ph2.

[0011] The SNS-Cr catalyst is a compound 1 shown in the following structural formula:

[0012] Preferably, the COF-supported oligomerization catalyst is selected from Ti(OBu n )4, NiCl2(Bu n 3P)2, Cr(EH)3 / 2,5-DMP, Cr(acac)3 / [(oF-CH)(o-MeOCH)P]2N(Pr i ), SNS-Cr, PNP / CrCl3(THF)3, [(2-Pe-S-Et)2-A]CrCl3, DPPB / [Cr(H2O)4Cl2]Cl·2H2O, NiCl2{[2-(5-Ph-Pyz)Et]2E}, NiCl2{[2-(3,5-Me2Pyz)Me]2BuA}, NiBr2{[2-(3,5-Me2Pyz)]EtA}, NiBr2[(3,5-Me2Pyz)2PhP] and decamethyl-bis(cyclopentadienyl)zirconium dichloride.

[0013] The COF-supported oligomerization catalyst can be prepared according to methods known in the art, for example, by the method disclosed in WO2022 / 133849, or by the method disclosed in Chinese application No. 202310731888.5 (A method for preparing a COF-supported olefin polymerization catalyst), the entire contents of which are incorporated herein by reference.

[0014] Preferably, the COF-supported oligomerization catalyst is prepared by the method disclosed in Chinese application No. 202310731888.5, wherein the method comprises the following steps:

[0015] (1) activating the COF material to obtain an activated COF material;

[0016] (2) first, under the protection of an inert atmosphere, at a temperature of 10-100° C., preferably about 20-100° C., more preferably about 40-80° C., reacting the activated COF material with a ligand constituting an olefin polymerization catalyst in a non-polar organic solvent to bind the ligand to the activated COF material;

[0017] Subsequently, at a temperature of 20-100° C., preferably 30-90° C., more preferably 40-80° C., in a non-polar organic solvent, a metal compound constituting an olefin polymerization catalyst is coordinated to the ligand to form a polyolefin catalyst bound to the COF material, and then solid-liquid separation is performed to collect the solid phase;

[0018] (3) Optionally, washing and drying the solid phase to obtain a COF-supported olefin polymerization catalyst.

[0019] For details on the method for preparing a COF-supported olefin polymerization catalyst disclosed in Chinese Application No. 202310731888.5, please refer to the disclosure in the application, the entire content of which is incorporated herein by reference.

[0020] Among them, regarding the COF material, the present application is known in the art and is disclosed in the above-mentioned WO2022 / 133849 and Chinese application No. 202310731888.5, all of which are incorporated herein by reference.

[0021] The COF materials specifically used in the embodiments and comparative examples of the present invention include COF1, COF300, COF303 and COF5. The structures of these COFs are shown below:

[0022] The COF-supported homopolymerization catalyst includes metallocene catalysts and post-metallocene catalysts known in the art that can be used as homopolymerization catalysts, especially metallocene catalysts and post-metallocene catalysts wherein the metal is selected from zirconium, titanium, palladium, hafnium, preferably selected from zirconium and titanium. Examples of the metallocene catalyst include, for example, rac-dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)zirconium dichloride, zirconocene dichloride, [CpMe4(SiMe2N-Bu t)]TiMe2, biscyclopentadienyl dimethyl hafnium, bisindenyl dimethyl zirconium, rac-vinylidene bridged bisindenyl zirconium dichloride, rac-dimethylsilyl bridged-bis(2-methylindenyl) zirconium dichloride, dimethylsilyl bridged-bisindenyl zirconium dichloride, diphenylcarbon bridged-cyclopentadienyl-Watyl zirconium dichloride, dimethylsilyl bridged-tetramethylcyclopentadienyl-tert-butylamino-dimethyltitanium, bisindenyl zirconium dichloride, biscyclopentadienyl-bisphenoxy zirconium, dimethylsilyl bridged Examples of the post-metallocene catalyst include phenoxyimine zirconium, phenoxyimine titanium, {2-SiMe3-6-{[(3,5-F2Ph)Im]Me}PhO}2TiCl2, [(N-Bu t Sa)CyP-A]2ZrCl2, {к 2 -1-P(2-OMe-Ph)2-2-P(O)(OEt)2-Ph}PdMe(2,6-Me2Pyd) + (SbF6) - , (β-Ki)2ZrCl2.

[0023] In the present invention, the preferred COF-supported homopolymerization catalyst is selected from rac-dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)zirconium dichloride, [CpMe4(SiMe2N-Bu t )]TiMe2, dichlorocyclopentadienyl zirconium dichloride, dimethylsilyl-bridged-bisindenyl zirconium dichloride, biscyclopentadienyl-bisphenoxy zirconium, dimethylsilyl-bridged-bisindenyl zirconium dichloride, phenoxyimide titanium and phenoxyimide zirconium.

[0024] The COF-supported homopolymerization catalyst can be prepared according to methods known in the art, for example, by the method disclosed in WO2022 / 133849, or by the method disclosed in Chinese application No. 202310731888.5, the entire contents of which are incorporated herein by reference.

[0025] Preferably, the COF-supported homopolymerization catalyst is prepared by the method disclosed in the above-mentioned Chinese application No. 202310731888.5.

[0026] In the present invention, the COF-supported oligomerization catalyst and the COF-supported homopolymerization catalyst can be pre-prepared by methods known in the art (for example, the method disclosed in WO2022 / 133849 or Chinese application No. 202310731888.5).

[0027] Alternatively, the COF-supported oligomerization catalyst and the COF-supported homopolymerization catalyst can be prepared in situ, for example, by placing the activated COF and the catalyst into a polymerization reactor, mixing them in a non-polar organic solvent for polymerization reaction at a polymerization reaction temperature of 20-180° C., preferably 50-120° C., for 1-20 minutes to prepare the COF-supported oligomerization catalyst or the COF-supported homopolymerization catalyst.

[0028] The amount of the COF-supported oligomerization catalyst or COF-supported homopolymerization catalyst used is generally 0.5-100 mg / L, preferably 1-50 mg / L, more preferably 3-20 mg / L, calculated relative to the volume (L) of the solvent used.

[0029] The cocatalyst is known in the art and generally includes, for example, alkylaluminum compounds, such as triethylaluminum and triisobutylaluminum; alkylaluminoxanes, such as methylaluminoxane and modified methylaluminoxane; tris(pentafluorophenyl)borane; and mixtures thereof. The amount of the cocatalyst used is generally 1-100 mmol / L, preferably 2-50 mmol / L, and more preferably 5-40 mmol / L, calculated relative to the volume (L) of the solvent used.

[0030] The non-polar organic solvent is known in the art and includes, for example, aliphatic compounds containing 5-12 carbon atoms, alicyclic compounds containing 6-12 carbon atoms, aromatic compounds containing 6-12 carbon atoms and their halides, ether compounds containing 4-12 carbon atoms, and mixtures thereof. Examples of the solvent include, for example, n-hexane, n-heptane, n-octane, n-dodecane, cyclohexane, toluene, xylene, mesitylene, chlorobenzene, 1,2,4-trichlorobenzene, ether, and mixtures thereof. Preferably, the solvent is selected from toluene, n-hexane, chlorobenzene, cyclohexane, n-heptane, isooctane, and mixtures thereof. More preferably, the solvent is selected from toluene, n-hexane, chlorobenzene, isooctane, and mixtures thereof.

[0031] Said step (1) is carried out under anhydrous and oxygen-free conditions, with a typical reaction temperature of 20-180° C., preferably 50-120° C.; a pressure of 0.2-4.0 MPa; and a reaction time of 5-100 min, preferably 10-30 min.

[0032] The oligomerization products include, for example, α-olefins such as 1-butene, 1-hexene, and 1-octene, 4-methyl-1-pentene, and the like.

[0033] The macromonomer with terminal double bonds is a polyethylene / polypropylene macromonomer, which generally has a molecular weight of 1000-10000 g / mol, preferably 2000-5000 g / mol, wherein the molecular weight is a number average molecular weight measured by high temperature gel permeation chromatography.

[0034] Optionally, when the selectivity of the oligomerization product of step (1) is low, the method further comprises a separation and purification step to increase the purity of the oligomerization product to, for example, greater than 90%. For example, when the oligomerization product is 4-methyl-1-pentene, its selectivity is generally less than 60%. In this case, the oligomerization product needs to be separated and purified to increase its purity to greater than 90%. The separation and purification methods are known in the art, such as extraction.

[0035] The olefin monomer is selected from C2-C10 olefins, such as ethylene, propylene, 1-butene, 1-hexene, 1-octene, 1-decene, etc. Preferably, the olefin monomer is selected from ethylene, propylene, 1-hexene, 1-octene.

[0036] In particular, the olefin monomers include the following:

[0037] (1) When the oligomerization product of step (1) is an α-olefin such as 1-butene, 1-hexene, or 1-octene, the olefin monomer is ethylene;

[0038] (2) When the oligomerization product of step (1) is 4-methyl-1-pentene, the olefin monomer is not required or can be an α-olefin such as 1-butene, 1-hexene, or 1-octene.

[0039] Therefore, accordingly, the polymerization reaction includes the following situations:

[0040] (1) When the oligomerization product of step (1) is an α-olefin such as 1-butene, 1-hexene, or 1-octene, the polymerization reaction is a copolymerization of the α-olefin and ethylene to produce an ethylene / α-polyolefin;

[0041] (2) When the oligomerization product of step (1) is 4-methyl-1-pentene, the polymerization reaction is a homopolymerization reaction of the separated and purified 4-methyl-1-pentene to produce poly-4-methyl-1-pentene (PMP); or it is a copolymerization reaction of 4-methyl-1-pentene with α-olefins such as 1-butene, 1-hexene, and 1-octene to produce 4-methyl-1-pentene / α-polyolefin.

[0042] The olefin polymerization catalysts are known in the art, including those disclosed in, for example, WO2022 / 133849, the entire contents of which are incorporated herein by reference. Specifically, the olefin polymerization catalysts include metallocene catalysts and post-metallocene catalysts known in the art.

[0043] The metallocene catalysts include, for example, zirconocene dichloride, biscyclopentadienyl hafnium dimethyl, bisindenyl dimethyl zirconium, rac-vinylidene bridged bisindenyl zirconium dichloride, rac-dimethylsilyl bridged-bis(2-methylindenyl) zirconium dichloride, dimethylsilyl bridged-bisindenyl zirconium dichloride, diphenylcarbo-cyclopentadienyl-hafnium dichloride, dimethylsilyl bridged-tetramethylcyclopentadienyl-tert-butylamino-dimethyltitanium, bisindenyl zirconium dichloride, methylsilyl (N-tert-butylamino) (tetramethylcyclopentadienyl) titanium dichloride, bis[2-(3',5'-di-tert-butylphenyl)-indenyl] zirconium dichloride, bis(2 -methyl-4,5-phenyl-indenyl) zirconium dichloride, biscyclopentadienyl-bisphenoxy zirconium, dimethylsilyl-bridged bisindenyl zirconium dichloride, diphenylcarbo-cyclopentadienyl-wheat zirconium dichloride, diphenylcarbo-cyclopentadienyl-(2-dimethylamino-wheat) zirconium dichloride, dimethylsilyl-bridged-tetramethylcyclopentadienyl-tert-butylamino-dimethyltitanium, dimethylsilyl-bridged-3-pyrrolylindenyl-tert-butylamino-dimethyltitanium, rac-dimethylsilyl-bridged-bis(2-methylindenyl) zirconium dichloride, dimethylsilyl-bridged-fluorenyl-tert-butylamino-dimethyltitanium and CGC-Ti catalyst.

[0044] The post-metallocene catalyst includes, for example, an imine-amine type catalyst, a ketimine type catalyst, an amidine type catalyst, a diimine palladium nickel type catalyst, a phenoxyimine type catalyst, and a pyridylamine hafnium catalyst.

[0045] Preferably, the olefin polymerization catalyst is selected from the group consisting of zirconocene dichloride, biscyclopentadienyl hafnium dimethyl, bisindenyl dimethyl zirconium, rac-vinylidene bridged bisindenyl zirconium dichloride, rac-dimethylsilyl-bis(2-methylindenyl) zirconium dichloride, diphenylcarbon bridged-cyclopentadienyl-Wat-based zirconium dichloride, dimethylsilyl-tetramethylcyclopentadienyl-tert-butylamino-dimethyltitanium, bisindenyl zirconium dichloride, methylsilyl(N-tert-butylamino)(tetramethylcyclopentadienyl)titanium dichloride, bis(2-methyl-4,5-phenyl-indenyl) zirconium dichloride, biscyclopentadienyl-bisphenoxy zirconium, dimethylsilyl-bisindenyl zirconium dichloride, diphenylcarbon bridged-cyclopentadienyl-Wat-based zirconium dichloride, CGC-Ti catalyst and pyridylamine hafnium catalyst.

[0046] More preferably, the olefin polymerization catalyst is selected from zirconocene dichloride, rac-vinylidene bridged bisindenyl zirconium dichloride, rac-dimethylsilyl bridged-bis(2-methylindenyl) zirconium dichloride, dimethylsilyl bridged-tetramethylcyclopentadienyl-tert-butylamino-dimethyltitanium, silyl(N-tert-butylamino)(tetramethylcyclopentadienyl)titanium dichloride, dimethylsilyl bridged bisindenyl zirconium dichloride, CGC-Ti catalyst and pyridinylamino hafnium catalyst. Most preferably, the olefin polymerization catalyst is selected from zirconocene dichloride, rac-vinylidene bridged bisindenyl zirconium dichloride, dimethylsilyl bridged bisindenyl zirconium dichloride, CGC-Ti catalyst and pyridinylamino hafnium catalyst.

[0047] The CGC-Ti catalyst is compound 2 shown in the following structural formula:

[0048] The pyridylamine hafnium catalyst is compound 3 shown in the following structural formula:

[0049] The amount of the olefin polymerization catalyst used is generally 1-100 mg / L, preferably 2-50 mg / L, more preferably 3-20 mg / L, calculated relative to the volume (L) of the solvent used.

[0050] The ratio of the oligomerization product to the olefin monomer is (0.2-2):1, preferably (0.3-1):1.

[0051] The ratio of the macromonomer with a terminal double bond to the olefin monomer is (0.001-0.1):1, preferably (0.01-0.04):1.

[0052] The step (2) is continued in the non-polar organic solvent under the anhydrous and oxygen-free conditions, with a typical reaction temperature of 20-180° C., preferably 80-160° C.; a pressure of 0.5-4.0 MPa, preferably 1.0-3.0 MPa; and a reaction time of 10-200 min, preferably 30-60 min.

[0053] The above preparation method is characterized in that: a COF-supported oligomerization catalyst or homopolymerization catalyst is used to carry out the first step of oligomerization or homopolymerization, which reduces the mutual influence of the two catalysts in the cascade polymerization system, thereby improving the efficiency of the cascade polymerization reaction and the quality of the polyolefin product, which is manifested in that the molecular weight and α-olefin content and therefore the processing and mechanical properties are higher than those of the cascade polymerization product using an unsupported catalyst.

[0054] When homopolymerization is carried out in step (1), the above preparation method can produce a polyolefin product with long chain branches.

[0055] Therefore, in a second aspect, the present invention relates to a polyolefin produced by the above process, which exhibits a higher molecular weight and α-olefin content. Example

[0056] The embodiments of the present invention will be clearly and completely described below with reference to the examples. Obviously, the examples described are merely illustrative and not restrictive. All other embodiments obtained by persons of ordinary skill in the art based on the examples of the present invention without creative work are within the scope of protection of the present invention.

[0057] Example 1

[0058] (1) Pre-prepare COF-loaded Ti(OBu n )4 Catalyst

[0059] COF-supported Ti(OBu) was prepared by the method for preparing COF-supported catalyst disclosed in WO2022 / 133849. n ) 4 catalyst, the specific steps are as follows:

[0060] COF1 was activated at 300 ° C under vacuum conditions for 6 h; under nitrogen atmosphere, 100 mg of activated COF1 and 100 mg of trimethylaluminum were dispersed in 100 ml of n-hexane, stirred at 25 ° C for 48 h, filtered, washed with toluene, and dried at 50 ° C to obtain pretreated COF1; in a nitrogen-filled glove box, 100 mg of pretreated COF1 and 50 mg of Ti(OBu n )4 catalyst and 100 ml of chlorobenzene were mixed, stirred at 0 ° C for 72 h, filtered, washed with toluene, and dried in vacuo at 50 ° C to obtain COF1-supported Ti(OBu n )4 catalyst.

[0061] (2) Application of catalyst in the preparation of ethylene-butadiene copolymer by cascade polymerization

[0062] A 1-liter autoclave was vacuumed at 140°C for 3 h, 600 ml of n-hexane was added to the autoclave, the ethylene pressure in the autoclave was adjusted to 25 bar, the temperature in the autoclave was adjusted to 50°C, and then 12 mg of the prepared COF1-loaded Ti(OBu) was added. n ) 4 catalyst and 10mmol triethylaluminum, react for 0.2h to obtain the oligomerization product 1-butene, wherein the 1-butene selectivity is 91.0%; and

[0063] The temperature in the autoclave was adjusted to 140°C, the ethylene pressure in the autoclave was adjusted to 35 bar, 5 mg of vinyl-bridged bisindenyl zirconium dichloride was added, and the reaction was continued for 0.5 h to obtain an ethylene / butene copolymer, wherein the butene insertion amount was 16.0 mol%, as measured by high-temperature nuclear magnetic resonance C spectroscopy (the same below); the weight-average molecular weight of the copolymer was 97,500 g / mol, as measured by high-temperature gel permeation chromatography (the same below).

[0064] Example 2

[0065] (1) Prepare COF-loaded NiCl2(Bu n 3P)2 catalyst

[0066] COF-supported NiCl2 (Bu n 3P)2 catalyst, the specific steps are as follows:

[0067] COF300 was activated at 300℃ under vacuum for 6h. Under nitrogen atmosphere, 200mg activated COF300 and 100mg NiCl2(Bu n 3P)2 catalyst was dispersed into 200ml toluene, stirred at 50℃ for 24h, filtered, washed with toluene, and dried at 70℃ to obtain COF300 loaded NiCl2(Bu n 3P)2 catalyst.

[0068] (2) Application of catalyst in the preparation of ethylene-butadiene copolymer by cascade polymerization

[0069] A 0.5-liter autoclave was vacuumed at 160°C for 3 h, 250 ml of toluene was added to the autoclave, the ethylene pressure in the autoclave was adjusted to 30 bar, the temperature in the autoclave was adjusted to 35°C, and then 5 mg of the prepared COF300 loaded Ti(OBu) was added. n ) 4 catalyst and 10mmol methylaluminoxane, react for 0.5h to obtain the oligomerization product 1-butene, with a 1-butene selectivity of 89.5%; and

[0070] The temperature in the autoclave was adjusted to 120° C., the ethylene pressure in the autoclave was kept constant, 2.5 mg of methylsilyl-bridged bisindenyl zirconium dichloride was added, and the reaction was continued for 1 hour to obtain an ethylene / butene copolymer, wherein the butene insertion amount was 18.0 mol%, and the weight average molecular weight of the copolymer was 89500 g / mol.

[0071] Example 3

[0072] A 1.0-liter autoclave was vacuum-treated at 150°C for 3 hours. 600 ml of cyclohexane was added to the autoclave, the ethylene pressure in the autoclave was adjusted to 30 bar, and the autoclave temperature was adjusted to 95°C. 50 mg of pretreated COF303, 50 mg of Cr(EH)3 catalyst, and 50 mg of 2,5-DMP were then added and mixed for 0.1 hour to obtain an in-situ prepared COF303-loaded Cr(EH)3 / 2,5-DMP catalyst.

[0073] Then, 15 mmol of methylaluminoxane was added and the reaction was carried out for 0.2 h to obtain the oligomerization product 1-hexene with a 1-hexene selectivity of 95.5%; and

[0074] Subsequently, the temperature in the autoclave was adjusted to 130° C., the ethylene pressure in the autoclave was adjusted to 15 bar, and 10.0 mg of CGC-Ti catalyst was added. The reaction was carried out for 0.5 h to obtain an ethylene / hexene copolymer, wherein the hexene insertion amount was 15.5 mol % and the weight-average molecular weight of the copolymer was 91,400 g / mol.

[0075] Example 4

[0076] (1) COF-loaded Cr(acac)3 / [(oF-CH)(o-MeOCH)P]2N(Pr i )catalyst

[0077] The COF-supported Cr(acac)3 / [(oF-CH)(o-MeOCH)P]2N(Pr i ) catalyst, the specific steps are as follows:

[0078] COF5 was activated at 300℃ under vacuum for 6h. In a glove box filled with nitrogen, 50mg of activated COF5 and 50mg of [(oF-CH)(o-MeOCH)P]2N(Pr i ) ligand was dispersed into 50 ml of toluene, stirred at 50 ° C for 24 h, filtered, washed with toluene, and dried in vacuo at 50 ° C to obtain COF5 loaded [(oF-CH)(o-MeOCH)P]2N(Pr i ) ligand; In a nitrogen-filled glove box, take 50mg COF5 loaded [(oF-CH)(o-MeOCH)P]2N(Pr i) ligand and 15 mg Cr(acac)3 catalyst were dispersed in 50 ml toluene, stirred at 50 ° C for 24 h, filtered, washed with toluene, and dried in vacuo at 50 ° C to obtain COF5-loaded Cr(acac)3 / [(oF-CH)(o-MeOCH)P]2N(Pr i )catalyst.

[0079] (2) Application of catalyst in cascade polymerization to prepare ethylene-hexane copolymer

[0080] A 1.0-liter autoclave was vacuumed at 150°C for 3 h, 600 ml of toluene was added to the autoclave, the ethylene pressure in the autoclave was adjusted to 40 bar, the temperature in the autoclave was adjusted to 75°C, and then 25 mg of COF5-loaded Cr(acac)3 / [(oF-CH)(o-MeOCH)P]2N(Pr i ) catalyzed; subsequently, 15 mmol of methylaluminoxane was added and the reaction was continued for 0.5 h to obtain an oligomerization product of 1-hexene, wherein the selectivity of 1-hexene was 93.1%; and

[0081] The temperature in the autoclave was adjusted to 150° C., the ethylene pressure in the autoclave was adjusted to 15 bar, 4.0 mg of vinyl-bridged bisindenyl zirconium dichloride was added, and the reaction was continued for 1 hour to obtain an ethylene / hexene copolymer, wherein the hexene insertion amount was 14.3 mol%, and the weight-average molecular weight of the copolymer was 96,500 g / mol.

[0082] Example 5

[0083] A 2.0-liter autoclave was vacuumed at 150°C for 3 h, 1.5 L of cyclohexane was added to the autoclave, the ethylene pressure in the autoclave was adjusted to 50 bar, and the temperature in the autoclave was adjusted to 80°C. Then, 20 mg of pretreated COF1 and 20 mg of SNS-Cr catalyst were added and mixed for 0.1 h to obtain the in situ prepared COF1-supported SNS-Cr catalyst;

[0084] Then, 30 mmol of methylaluminoxane was added and the reaction was carried out for 0.2 h to obtain the oligomerization product 1-hexene with a 1-hexene selectivity of 96.0%; and

[0085] Subsequently, the temperature in the autoclave was adjusted to 140° C., the ethylene pressure in the autoclave was adjusted to 15 bar, and 5.0 mg of CGC-Ti catalyst was added. The reaction was continued for 0.5 h to obtain an ethylene / hexene copolymer, wherein the hexene insertion amount was 15.2 mol % and the weight-average molecular weight of the copolymer was 102,000 g / mol.

[0086] Example 6

[0087] (1) Pre-preparation of COF-loaded PNP / CrCl3(THF)3 catalyst

[0088] The COF-supported PNP / CrCl3(THF)3 catalyst was prepared by the method for preparing a COF-supported catalyst disclosed in WO2022 / 133849. The specific steps are as follows:

[0089] COF300 was activated at 500°C under vacuum conditions for 6 hours; under nitrogen atmosphere, 200 mg of activated COF300 and 200 mg of PNP / CrCl3(THF)3 catalyst were dispersed into 200 ml of toluene, stirred and reacted at 50°C for 24 hours, filtered, washed with toluene, and dried at 70°C to obtain COF300-loaded PNP / CrCl3(THF)3 catalyst.

[0090] (2) Application of catalyst in the preparation of ethyloctane copolymer by cascade polymerization

[0091] A 0.5-liter autoclave was vacuumed at 160° C. for 3 hours, 250 ml of toluene was added to the autoclave, the ethylene pressure in the autoclave was adjusted to 30 bar, and the temperature in the autoclave was adjusted to 35° C. Then, 5 mg of the prepared COF300-supported PNP / CrCl3(THF)3 catalyst and 8 mmol of methylaluminoxane were added and reacted for 0.2 hours to obtain the oligomerization product 1-octene, wherein the 1-octene selectivity was 68.5%; and

[0092] The temperature in the autoclave was adjusted to 120° C., the ethylene pressure in the autoclave was adjusted to 10 bar, 2.5 mg of CGC-Ti catalyst was added, and the reaction was continued for 0.5 h to obtain an ethylene / octene copolymer, wherein the octene insertion amount was 12.0 mol % and the weight average molecular weight of the copolymer was 117100 g / mol.

[0093] Example 7

[0094] (1) Pre-preparation of COF-supported phenoxyimine zirconium catalyst

[0095] The COF-supported phenoxyimine zirconium catalyst was prepared by the method for preparing a COF-supported catalyst disclosed in WO2022 / 133849. The specific steps are as follows:

[0096] COF303 was activated at 300°C under vacuum conditions for 8 hours; under the protection of a nitrogen atmosphere, 100 mg of activated COF303 and 100 mg of trimethylaluminum were dispersed in 100 ml of n-hexane, stirred and reacted at 25°C for 48 hours, filtered, washed with toluene, and dried at 50°C to obtain pretreated COF303; in a nitrogen-filled glove box, 100 mg of pretreated COF303, 50 mg of phenoxyimine zirconium catalyst and 100 ml of toluene were mixed, stirred and reacted at 20°C for 72 hours, filtered, washed with toluene, and vacuum dried at 30°C to obtain COF303-loaded phenoxyimine zirconium catalyst.

[0097] (2) Application of catalysts in the preparation of long-chain branched copolymers by cascade polymerization

[0098] A 1-liter autoclave was vacuumed at 140° C. for 3 hours, 600 ml of toluene was added to the autoclave, the ethylene pressure in the autoclave was adjusted to 11 bar, and the temperature in the autoclave was adjusted to 90° C. Then, 3.0 mg of the prepared COF303-supported phenoxyimine zirconium catalyst and 10 mmol of methylaluminoxane were added and reacted for 0.2 hours to obtain a homopolymer product, a polyethylene macromonomer, having a terminal double bond ratio of 91.0%; and

[0099] The temperature in the autoclave was adjusted to 120° C., the ethylene pressure in the autoclave was maintained constant, 5 mg of CGC-Ti catalyst and 40 g of 1-octene were added, and the reaction was continued for 0.5 h to obtain a long-chain branched copolymer with an octene insertion content of 15.6 mol % and a weight-average molecular weight of 105,000 g / mol.

[0100] Example 8

[0101] (1) Pre-preparation of COF-supported zirconocene dichloride catalyst

[0102] The COF-supported zirconocene dichloride catalyst was prepared by the method for preparing a COF-supported catalyst disclosed in WO2022 / 133849. The specific steps are as follows:

[0103] COF5 was activated at 400°C under vacuum conditions for 8 hours; under the protection of a nitrogen atmosphere, 100 mg of activated COF5 and 100 mg of dichlorozirconocene catalyst were dispersed in 100 ml of toluene, stirred and reacted at 50°C for 24 hours, filtered, washed with toluene, and dried at 70°C to obtain a COF5-loaded dichlorozirconocene catalyst.

[0104] (2) Application of catalysts in the preparation of long-chain branched copolymers by cascade polymerization

[0105] A 0.5-liter autoclave was vacuumed at 150° C. for 3 hours, 250 ml of toluene was added to the autoclave, the ethylene pressure in the autoclave was adjusted to 11 bar, and the temperature in the autoclave was adjusted to 90° C. Then, 45 mg of the prepared COF5-supported zirconocene dichloride catalyst and 6 mmol of methylaluminoxane were added and reacted for 0.2 hours to obtain a homopolymer product, a polyethylene macromonomer, having a terminal double bond ratio of 75.0%; and

[0106] The temperature in the autoclave was adjusted to 120° C., the ethylene pressure in the autoclave was maintained constant, 3 mg of CGC-Ti catalyst and 40 g of 1-octene were added, and the reaction was continued for 0.5 h to obtain a long-chain branched copolymer with an octene insertion content of 14.5 mol % and a weight-average molecular weight of 95,000 g / mol.

[0107] Example 9

[0108] A 1-liter autoclave was vacuumed at 160° C. for 3 hours, 600 ml of toluene was added to the autoclave, the propylene pressure in the autoclave was adjusted to 2 bar, and the temperature in the autoclave was adjusted to 105° C. Then, 10.0 mg of activated COF1 and 2.5 mg of rac-dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl) zirconium dichloride catalyst were added and mixed for 0.1 hour to obtain the in situ prepared COF1-supported rac-dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl) zirconium dichloride catalyst;

[0109] Then, 15 mmol of methylaluminoxane was added and the reaction was carried out for 0.2 h to obtain a homopolymerized isotactic polypropylene macromonomer having a terminal double bond ratio of 75.0% and an isotacticity of 92%.

[0110] Subsequently, the temperature in the autoclave was adjusted to 120° C., the propylene pressure in the autoclave was maintained constant, 5 mg of CGC-Ti catalyst and 40 g of 1-octene were added, and the reaction was continued for 0.5 h to obtain a long-chain branched copolymer, wherein the octene insertion amount was 16.5 mol % and the weight-average molecular weight of the copolymer was 65,000 g / mol.

[0111] Example 10

[0112] (1) Pre-preparation of COF-supported decamethyl-biscyclopentadiene zirconium dichloride catalyst

[0113] The COF-supported decamethyl-biscyclopentadiene zirconium dichloride catalyst was prepared by the method for preparing a COF-supported catalyst disclosed in WO2022 / 133849. The specific steps are as follows:

[0114] COF300 was activated at 400°C under vacuum conditions for 6 hours; under nitrogen atmosphere, 100 mg of activated COF300 and 100 mg of triethylaluminum were dispersed in 100 ml of n-hexane, stirred and reacted at 40°C for 24 hours, filtered, washed with toluene, and dried at 50°C to obtain pretreated COF300; in a nitrogen-filled glove box, 50 mg of pretreated COF300, 20 mg of decamethyl-biscyclopentadiene zirconium dichloride catalyst and 50 ml of toluene were mixed, stirred and reacted at 20°C for 48 hours, filtered, washed with toluene, and vacuum dried at 30°C to obtain COF300-loaded decamethyl-biscyclopentadiene zirconium dichloride catalyst.

[0115] (2) Application of catalysts in the preparation of PMP by cascade polymerization

[0116] 1-liter autoclave 1 and 1-liter autoclave 2 were vacuum-treated at 150°C for 2 hours. 600 ml of toluene were added to each of autoclaves 1 and 2. The propylene pressure in autoclave 1 was adjusted to 22 bar, and the temperature in autoclave 1 was adjusted to 30°C. Then, 10.0 mg of the prepared COF300-supported decamethyl-biscyclopentadiene zirconium dichloride catalyst and 10 mmol of methylaluminoxane were added and reacted for 1 hour to obtain 4-methyl-1-pentene with a 4-methyl-1-pentene selectivity of 58.0%.

[0117] 4-Methyl-1-pentene was separated and purified by extraction to achieve a purity of 95.4%.

[0118] The separated and purified 4-methyl-1-pentene was put into kettle 2, the temperature in kettle 2 was adjusted to 50°C, 5 mg of pyridylamine hafnium catalyst and 100 mg of methylaluminoxane were added, and the reaction was carried out for 0.5 h to obtain poly-4-methyl-1-pentene (PMP) with a weight-average molecular weight of 195,000 g / mol.

[0119] Example 11

[0120] (1) Pre-preparation of COF-supported decamethyl-biscyclopentadiene zirconium dichloride catalyst

[0121] The COF-supported decamethyl-biscyclopentadiene zirconium dichloride catalyst was prepared by the method for preparing a COF-supported catalyst disclosed in WO2022 / 133849. The specific steps are as follows:

[0122] COF303 was activated at 400°C under vacuum conditions for 6 hours; under the protection of a nitrogen atmosphere, 100 mg of activated COF303 and 100 mg of decamethyl-biscyclopentadiene zirconium dichloride catalyst were dispersed in 100 ml of toluene, stirred and reacted at 50°C for 24 hours, filtered, washed with toluene, and dried at 50°C to obtain a COF303-loaded decamethyl-biscyclopentadiene zirconium dichloride catalyst.

[0123] (2) Application of catalyst in cascade polymerization to prepare 4-methyl-1-pentene / α-polyolefin

[0124] 1-liter autoclave 1 and 1-liter autoclave 2 were vacuum-treated at 160° C. for 3 h. 600 ml of toluene were added to each of autoclaves 1 and 2. The propylene pressure in autoclave 1 was adjusted to 22 bar, and the temperature in autoclave 1 was adjusted to 30° C. Then, 10.0 mg of the prepared COF303-supported decamethyl-biscyclopentadiene zirconium dichloride catalyst and 12 mmol of methylaluminoxane were added and reacted for 1 h to obtain 4-methyl-1-pentene with a 4-methyl-1-pentene selectivity of 56.0%.

[0125] 4-Methyl-1-pentene was separated and purified by extraction to achieve a purity of 94.7%.

[0126] The separated and purified 4-methyl-1-pentene was put into kettle 2, the temperature in kettle 2 was adjusted to 50°C, 5 mg of pyridylamine hafnium catalyst, 20 g of 1-hexene and 100 mg of methylaluminoxane were added, and the reaction was carried out for 0.5 h to obtain a 4-methyl-1-pentene / 1-hexene copolymer with a weight-average molecular weight of 135,000 g / mol.

[0127] Comparative Example 1

[0128] Application of SNS-Cr catalyst in cascade polymerization to prepare ethylene copolymers

[0129] A 2.0-liter autoclave was vacuumed at 150° C. for 3 hours, 1.5 L of cyclohexane was added to the autoclave, the ethylene pressure in the autoclave was adjusted to 50 bar, and the temperature in the autoclave was adjusted to 80° C. Then, 20 mg of SNS-Cr catalyst and 30 mmol of methylaluminoxane were added and reacted for 0.2 hours to obtain the oligomerization product 1-hexene, wherein the 1-hexene selectivity exceeded 99.0%; and

[0130] The temperature in the autoclave was adjusted to 140° C., the ethylene pressure in the autoclave was adjusted to 15 bar, 5.0 mg of CGC-Ti catalyst was added, and the reaction was continued for 0.5 h to obtain an ethylene / hexene copolymer, wherein the hexene insertion amount was 15.2 mol % and the weight average molecular weight of the copolymer was 48,300 g / mol.

[0131] By comparing the ethylene / hexene copolymer prepared in Example 5 and Comparative Example 1, it can be seen that the molecular weight of the copolymer obtained in Example 5 using the COF-supported SNS-Cr catalyst is significantly improved, which indicates that the introduction of the COF-supported catalyst into the cascade polymerization technology reduces the effect of the SNS-Cr catalyst on the copolymerization catalyst.

[0132] Comparative Example 2

[0133] Application of phenoxyimine zirconium catalyst in cascade polymerization to prepare long-chain branched copolymers

[0134] A 1-liter autoclave was vacuumed at 140° C. for 3 hours, 600 ml of toluene was added to the autoclave, the ethylene pressure in the autoclave was adjusted to 11 bar, the temperature in the autoclave was adjusted to 90° C., and then 1.3 mg of phenoxyimine zirconium catalyst and 10 mmol of methylaluminoxane were added and reacted for 0.2 hours to obtain a homopolymerized polyethylene macromonomer with a terminal double bond ratio of 93.0%; and

[0135] The temperature in the autoclave was adjusted to 120° C., the ethylene pressure in the autoclave was maintained constant, 5 mg of CGC-Ti catalyst and 40 g of 1-octene were added, and the reaction was continued for 0.5 h to obtain a long-chain branched copolymer with an octene insertion content of 18.4 mol % and a weight-average molecular weight of 125,000 g / mol.

[0136] By comparing the copolymers prepared in Example 7 and Comparative Example 2, it can be seen that the molecular weight of the copolymer obtained in Example 7 using the COF-supported phenoxyimine zirconium catalyst is significantly improved, and the ability to copolymerize α-olefins is also significantly improved, which indicates that the introduction of the COF-supported catalyst into the cascade polymerization technology reduces the influence of the phenoxyimine zirconium catalyst on the copolymerization catalyst.

[0137] Comparative Example 3

[0138] Application of rac-dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)zirconium dichloride catalyst in the preparation of long-chain branched copolymers by cascade polymerization

[0139] A 1-liter autoclave was vacuumed at 160° C. for 3 hours, 600 ml of toluene was added to the autoclave, the propylene pressure in the autoclave was adjusted to 2 bar, and the temperature in the autoclave was adjusted to 105° C. Then, 2.0 mg of iPM-Zr and 15 mmol of methylaluminoxane were added and reacted for 0.2 hours to obtain a homopolymer product, an isotactic polypropylene macromonomer, having a terminal double bond ratio of 78.0% and an isotacticity of 86%; and

[0140] The temperature in the autoclave was adjusted to 120° C., the propylene pressure in the autoclave was maintained constant, 5 mg of CGC-Ti catalyst and 40 g of 1-octene were added, and the reaction was continued for 0.5 h to obtain a long-chain branched copolymer with an octene insertion content of 18.1 mol % and a weight-average molecular weight of 78,000 g / mol.

[0141] By comparing the copolymers prepared in Example 9 and Comparative Example 3, it can be seen that the use of the COF-supported rac-dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)zirconium dichloride catalyst in Example 9 not only improves the isotacticity of the macromonomer produced by the catalyst, but also reduces the effect of the catalyst on the copolymerization catalyst, and the ability to copolymerize α-olefins and the molecular weight of the copolymer are significantly improved.

[0142] Comparative Example 4

[0143] Application of Decamethyl-Dicyclopentadiene Zirconium Dichloride Catalyst in Cascade Polymerization to Prepare 4-Methyl-1-Pentene / α-Polyolefin

[0144] 1-liter autoclave 1 and 1-liter autoclave 2 were vacuum-treated at 160° C. for 3 hours. 600 ml of toluene were added to each of autoclave 1 and autoclave 2. The propylene pressure in autoclave 1 was adjusted to 22 bar, and the temperature in autoclave 1 was adjusted to 30° C. Then, 2.0 mg of decamethyl-biscyclopentadiene zirconium dichloride catalyst and 12 mmol of methylaluminoxane were added and reacted for 1 hour to obtain 4-methyl-1-pentene with a 4-methyl-1-pentene selectivity of 56.5%.

[0145] 4-Methyl-1-pentene was separated and purified by extraction to achieve a purity of 95.2%.

[0146] The separated and purified 4-methyl-1-pentene was added to kettle 2, the temperature in kettle 2 was adjusted to 50°C, 5 mg of pyridylamine hafnium catalyst, 20 g of 1-hexene and 100 mg of methylaluminoxane were added, and the reaction was carried out for 0.5 h to obtain a 4-methyl-1-pentene / 1-hexene copolymer with a weight-average molecular weight of 155,000 g / mol.

[0147] By comparing the copolymers prepared in Example 11 and Comparative Example 4, it can be seen that the molecular weight of the copolymer obtained in Example 11 using the COF-supported decamethyl-biscyclopentadiene zirconium dichloride catalyst is significantly improved, which indicates that the introduction of the COF-supported catalyst into the cascade polymerization technology reduces the influence of the decamethyl-biscyclopentadiene zirconium dichloride catalyst on the copolymerization catalyst.

[0148] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the same. Although the present invention has been described in detail with reference to preferred embodiments, persons skilled in the art should understand that the specific implementation methods of the present invention may still be modified or some technical features may be replaced by equivalents without departing from the spirit of the technical solutions of the present invention. All of these should fall within the scope of the technical solutions claimed for protection by the present invention.

Claims

1. A method for preparing polyolefins by cascade polymerization, comprising the steps of: (1) in the presence of a COF-supported oligomerization catalyst or a COF-supported homopolymerization catalyst and an optional co-catalyst, oligomerizing ethylene and / or propylene monomers in a non-polar organic solvent to obtain an oligomerization product or a macromonomer with a terminal double bond, respectively; and (2) Then, the oligomerization product or the macromonomer with terminal double bonds is further polymerized with an olefin monomer in a non-polar organic solvent in the presence of an olefin polymerization catalyst under anhydrous and oxygen-free conditions to obtain a polyolefin product.

2. The method according to claim 1, wherein the COF-supported oligomerization catalyst is selected from 1,2,3,4,5-Ph5-Cp / Cr(EH)3, {2-[1-(3H-Ind)CyH]Th}TiCl3, decamethyl-biscyclopentadiene zirconium dichloride, Ar2PN(Me)PAr2 / Cr, {HN(CH2CH2PPh2)2}CrCl3, Cr(EH)3 / 2,5-DMP, [(2-Pe-S-Et)2-A]CrCl3, DPPB / [Cr(H2O)4Cl2]Cl·2H2O, SNS-Cr, NiCl2{[2-(5-Ph-Pyz)Et]2E}, NiCl2{[2-(3,5-Me2Pyz)Me]2BuA}, Mo(μ-N-Bu t AlCl2)2, NiBr2{[2-(3,5-Me2Pyz)]EtA}, V(NAd)Cl2[8-(2,6-Me2An)-5,6,7-H3Qu], Ni Br2[(3,5-Me2Pyz)2PhP], WCl6 / 2DippNH2 / 4NEt3, TaCl3(NDipp)(tmeda), Nb(N-2,6-Pr j 2Ph)Me2[2-(2,6-Me2Ph)NCH2(Pyd)], Ti(OBu n )4, NiCl2(Bu n 3P)2,Cr(acac)3 / Ph2P)2NPr i ,Cr(acac)3 / [(oF-CH)(o-MeOCH)P]2N(Pr i ), Cr(CO)4[(Ph2P)2NPr j ], [(DPPDME)CrCl3]2, CrCl2(THF)2 / Ph2PN(Me)(CH2)3N(Me)PPh2, Cr(SBDP)Cl3, [2-CrCl2] + [B(C6F5)4] - , Cr(acac)3 / Ph2PN(But)PPh2, PNP / CrCl3(THF)3 and Cr(CO)6 / Ph2PN(Pr j )Si(CH3)2CH2Ph2.

3. The method according to claim 2, wherein the COF-supported oligomerization catalyst is selected from Ti(OBu n )4, NiCl2(Bu n 3P)2, Cr(EH)3 / 2,5-DMP, Cr(acac)3 / [(oF-CH)(o-MeOCH)P]2N(Pr i ), SNS-Cr, PNP / CrCl3(THF)3, [(2-Pe-S-Et)2-A]CrCl3, DPPB / [Cr(H2O)4Cl2]Cl·2H2O, NiCl2{[2-(5-Ph-Pyz)Et]2E}, NiCl2{[2-(3,5-Me2Pyz)Me]2BuA}, NiBr2{[2-(3,5-Me2Pyz)]EtA}, NiBr2[(3,5-Me2Pyz)2PhP] and decamethyl-bis(cyclopentadienyl)zirconium dichloride.

4. The method according to claim 1, wherein the COF-supported homopolymerization catalyst is selected from rac-dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)zirconium dichloride, zirconocene dichloride, [CpMe4(SiMe2N-Bu t )]TiMe2, biscyclopentadienyl dimethyl hafnium, bisindenyl dimethyl zirconium, rac-vinylidene bridged bisindenyl zirconium dichloride, rac-dimethylsilyl bridged-bis(2-methylindenyl) zirconium dichloride, dimethylsilyl bridged-bisindenyl zirconium dichloride, diphenylcarbobridged-cyclopentadienyl-Watyl zirconium dichloride, dimethylsilyl bridged-tetramethylcyclopentadienyl-tert-butylamino-dimethyltitanium, bisindenyl zirconium dichloride, biscyclopentadienyl-bisphenoxy zirconium, dimethylsilyl bridged-bisindenyl zirconium dichloride, diphenylcarbobridged-cyclopentadienyl-Watyl zirconium dichloride, Diphenyl carbo-cyclopentadienyl-(2-dimethylamino-hutyl) zirconium dichloride, dimethylsilyl-tetramethylcyclopentadienyl-tert-butylamino-dimethyltitanium, dimethylsilyl-3-pyrrolylindenyl-tert-butylamino-dimethyltitanium, rac-dimethylsilyl-bis(2-methylindenyl) zirconium dichloride, dimethylsilyl-fluorenyl-tert-butylamino-dimethyltitanium, phenoxyimide zirconium, phenoxyimide titanium, {2-SiMe3-6-{[(3,5-F2Ph)Im]Me}PhO}2TiCl2, [(N-Bu t Sa)CyP-A]2ZrCl2, {к 2 -1-P(2-OMe-Ph)2-2-P(O)(OEt)2-Ph}PdMe(2,6-Me2Pyd) + (SbF6) - and (β-Ki)2ZrCl2.

5. The method according to claim 4, wherein the COF-supported homopolymerization catalyst is selected from rac-dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)zirconium dichloride, [CpMe4(SiMe2N-Bu t )]TiMe2, dichlorobis(cyclopentadienyl) zirconium dichloride, dimethylsilyl-bis(indenyl) zirconium dichloride, bis(cyclopentadienyl)-bis(phenoxy) zirconium, dimethylsilyl-bis(indenyl) zirconium dichloride, phenoxyimide titanium and phenoxyimide zirconium.

6. The method according to claim 1, wherein the amount of the COF-supported oligomerization catalyst or the COF-supported homopolymerization catalyst is 0.5-100 mg / L, preferably 1-50 mg / L, more preferably 3-20 mg / L, calculated relative to the volume (L) of the non-polar organic solvent used.

7. The method according to claim 1, wherein the reaction temperature of step (1) is 20-180°C, preferably 50-120°C; the pressure is 0.2-4.0 MPa; and the reaction time is 5-100 min, preferably 10-30 min.

8. The method according to claim 1, wherein the oligomerization product comprises α-olefins such as 1-butene, 1-hexene and 1-octene, and 4-methyl-1-pentene.

9. The method according to claim 1, wherein the macromonomer with terminal double bonds is a polyethylene / polypropylene macromonomer having a molecular weight of 1000-10000 g / mol, preferably a molecular weight of 2000-5000 g / mol.

10. The method according to any one of claims 1 to 9, wherein the olefin polymerization catalyst is selected from the group consisting of dichlorobis(cyclopentadienyl) zirconium, bis(cyclopentadienyl) hafnium dimethyl, bis(indenyl) dimethyl zirconium, rac-vinylidene bridged bis(indenyl) zirconium dichloride, rac-dimethylsilyl-bis(2-methylindenyl) zirconium dichloride, diphenylcarbo-cyclopentadienyl-Wat-based zirconium dichloride, dimethylsilyl-tetramethylcyclopentadienyl-tert-butylamino-dimethyltitanium, bis(indenyl) zirconium dichloride, methylsilyl(N-tert-butylamino)(tetramethylcyclopentadienyl) titanium dichloride, bis(2-methyl-4,5-phenyl-indenyl) zirconium dichloride, bis(cyclopentadienyl)-bisphenoxy zirconium, dimethylsilyl-bis(indenyl) zirconium dichloride, diphenylcarbo-cyclopentadienyl-Wat-based zirconium dichloride, CGC-Ti catalyst, and pyridineamino hafnium catalyst.

11. The method according to any one of claims 1 to 9, wherein the ratio of the oligomerization product to the olefin monomer is (0.2-2):1, preferably (0.3-1):

1.

12. The method according to any one of claims 1 to 9, wherein the ratio of the macromonomer with terminal double bonds to the olefin monomer is (0.001-0.1):1, preferably (0.01-0.04):

1.

13. The method according to any one of claims 1 to 9, wherein the reaction temperature in step (2) is 20-180°C, preferably 80-160°C; the pressure is 0.5-4.0 MPa, preferably 1.0-3.0 MPa; and the reaction time is 10-200 min, preferably 30-60 min.

14. A polyolefin obtained according to the process according to any one of claims 1 to 17.