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EP-4737490-A1 - METHOD FOR PREPARING POLYOLEFIN BY MEANS OF CASCADE POLYMERIZATION

EP4737490A1EP 4737490 A1EP4737490 A1EP 4737490A1EP-4737490-A1

Abstract

The present invention provides a method for preparing polyolefins by cascade polymerization, comprising the following steps: (1) under anhydrous and anaerobic conditions, ethylene and/or propylene monomers are subjected to oligomerization reaction in a non-polar organic solvent in the presence of a COF supported oligomerization catalyst or a COF supported homopolymerization catalyst, and optional cocatalyst, to obtain an oligomeric product or macromonomer with terminal double bonds, respectively; and (2) then, under anhydrous and anaerobic conditions, in the presence of an olefin polymerization catalyst, the oligomeric product or macromonomer with terminal double bonds is further polymerized with an olefin monomer in a non-polar organic solvent to obtain the polyolefins.

Inventors

  • WANG, WENJUN
  • LIM, Khak Ho
  • ZHU, Bangban
  • LIU, Pingwei
  • LI, Bogeng
  • YAO, ZHEN
  • HU, Jijiang
  • YANG, Xuan
  • SHI, Shengbin
  • WANG, QINGYUE

Assignees

  • INSTITUTE OF ZHEJIANG UNIVERSITY-QUZHOU

Dates

Publication Date
20260506
Application Date
20230629

Claims (14)

  1. A method for preparing polyolefins by cascade polymerization, comprising the following steps: (1) under anhydrous and anaerobic conditions, ethylene and/or propylene monomers are subjected to oligomerization reaction in a non-polar organic solvent in the presence of a COF supported oligomerization catalyst or a COF supported homopolymerization catalyst, and optional cocatalyst, to obtain an oligomeric product or macromonomer with terminal double bonds, respectively; and (2) then, under anhydrous and anaerobic conditions, in the presence of an olefin polymerization catalyst, the oligomeric product or macromonomer with terminal double bonds is further polymerized with an olefin monomer in a non-polar organic solvent to obtain the polyolefins.
  2. The method according to claim 1, wherein the COF supported oligomerization catalyst is selected from the group consisting of 1,2,3,4,5-Ph 5 -Cp/Cr (EH) 3 , {2- [1-(3H-Ind) CyH]Th} TiCl 3 , decamethyl-dicyclopentadiene zirconium dichloride, Ar 2 PN(Me)PAr 2 /Cr , {HN(CH 2 CH 2 PPh 2 ) 2 }CrCl 3 , Cr(EH) 3 /2,5-DMP , [(2-Pe-S-Et) 2 -A]CrCl 3 , DPPB/[Cr(H 2 O) 4 Cl 2 ]Cl2H 2 O , SNS-Cr , NiCl 2 {[2-(5-Ph-Pyz)Et] 2 E} , NiCl 2 {[2-(3,5-Me 2 Pyz)Me] 2 BuA} , Mo(µ-N-Bu t AlCl 2 ) 2 , NiBr 2 {[2-(3,5-Me 2 Pyz)]EtA} , V(NAd)Cl 2 [8-(2,6-Me 2 An)-5,6,7-H 3 Qu] , NiBr 2 [(3,5-Me 2 Pyz) 2 PhP] , WCl 6 /2DippNH 2 /4NEt 3 , TaCl 3 (NDipp)(tmeda) , Nb(N-2,6-Pr j 2 Ph)Me 2 [2-(2,6-Me 2 Ph)NCH 2 (Pyd)] , Ti(OBu n ) 4 , NiCl 2 (Bu n 3 P) 2 , Cr(acac) 3 /Ph 2 P) 2 NPr i , Cr(acac) 3 /[( o -F-CH)( o -MeOCH)P] 2 N(Pr i ) , Cr(CO) 4 [(Ph 2 P) 2 NPr j ] , [(DPPDME)CrCl 3 ] 2 , CrCl 2 (THF) 2 /Ph 2 PN(Me)(CH 2 )3N(Me)PPh 2 , Cr(SBDP)Cl 3 , [2-CrCl 2 ] + [B(C 6 F 5 ) 4 ] - , Cr(acac) 3 /Ph 2 PN(Bu t )PPh 2 , PNP/CrCl 3 (THF) 3 and Cr (CO) 6 /Ph 2 PN (Pr j ) Si (CH 3 ) 2 CH 2 Ph 2 .
  3. The method according to claim 2, wherein the COF supported oligomerization catalyst is selected from the group consisting of Ti (OBu n ) 4 , NiCl 2 (Bu n 3 P) 2 , Cr (EH) 3 /2,5-DMP, Cr (acac) 3 /[( o -F-CH) ( o -MeOCH)P] 2 N (Pr i ), SNS-Cr, PNP/CrCl 3 (THF) 3 , [(2-Pe-S-Et) 2 -A] CrCl 3 , DPPB/[Cr (H 2 O) 4 Cl 2 ] Cl·2H 2 O, NiCl 2 {[2-(5-Ph-Pyz) Et] 2 E}, NiCl 2 {[2-(3,5-Me 2 Pyz) Me] 2 BuA}, NiBr 2 {[2-(3,5-Me 2 Pyz)]EtA}, NiBr 2 [(3,5-Me 2 Pyz) 2 PhP], and decamethyl-dicyclopentadiene zirconium dichloride.
  4. The method according to claim 1, wherein the COF supported homopolymerization catalyst is selected from the group consisting of rac-dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl) zirconium dichloride, zirconocene dichloride, [CpMe 4 (SiMe 2 N-Bu t )]TiMe 2 , dicyclopentadienyl dimethyl hafnium, diindenyl dimethyl zirconium, rac-vinylidene-bridged diindenyl zirconium dichloride, rac-dimethylsilyl-bridged di(2-methylindenyl) zirconium dichloride, dimethylsilyl-bridged diindenyl zirconium dichloride, diphenylcarbon-bridged cyclopentadienyl fluorenyl zirconium dichloride, dimethylsilyl-bridged tetramethyl cyclopentadienyl tert-butylamino dimethyl titanium, diindenyl zirconium dichloride, dicyclopentadienyl zirconium bis(phenoxide), dimethylsilyl-bridged diindenyl zirconium dichloride, diphenylcarbon-bridged cyclopentadienyl fluorenyl zirconium dichloride, diphenylcarbon-bridged cyclopentadienyl-2-dimethylamino-fluorenyl )zirconium dichloride, dimethylsilyl-bridged tetramethyl cyclopentadienyl tert-butylamino dimethyl titanium, dimethylsilyl-bridged 3-pyrrolyindenyl tert-butylamino dimethyl titanium, rac-dimethylsilyl-bridged di(2-methylindenyl) zirconium dichloride, dimethylsilyl-bridged fluorenyl tert-butylamino dimethyl titanium, zirconium phenoxide imine, titanium phenoxide imine, {2-SiMe 3 -6-{[(3,5-F 2 Ph)Im]Me}PhO} 2 TiCl 2 , [(N-Bu t Sa)CyP-A] 2 ZrCl 2 , {κ 2 -1-P(2-OMe-Ph) 2 -2-P(O)(OEt) 2 -Ph}PdMe(2,6-Me 2 Pyd) + (SbF 6 )- and (β- Ki) 2 ZrCl 2 .
  5. The method according to claim 4, wherein the COF supported homopolymerization catalyst is selected from the group consisting of rac-dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl) zirconium dichloride, [CpMe 4 (SiMe 2 N-Bu t )]TiMe 2 , zirconocene dichloride, dimethylsilyl-bridged diindenyl zirconium dichloride, dicyclopentadienyl zirconium bis(phenoxide), dimethylsilyl-bridged diindenyl zirconium dichloride, titanium phenoxide imine, and zirconium phenoxide imine.
  6. The method according to claim 1, wherein the amount of the COF supported oligomerization catalyst or COF supported homopolymerization catalyst is 0.5-100 mg/L, preferably 1-50 mg/L, and 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 in step (1), the reaction temperature is 20-180°C, preferably 50-120°C; the pressure is 0.2-4.0MPa; and the reaction time is 5-100mins, preferably 10-30mins.
  8. The method according to claim 1, wherein the oligomeric product comprises alpha-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 with a molecular weight of 1000-10000 g/mol, preferably 2000-5000 g/mol.
  10. The method according to any one of claims 1-9, wherein the olefin polymerization catalyst is selected from the group consisting of zirconocene dichloride, dicyclopentadienyl dimethyl hafnium, diindenyl dimethyl zirconium, rac-vinylidene-bridged diindenyl zirconium dichloride, rac-dimethylsilyl-bridged di(2-methylindenyl) zirconium dichloride, diphenylcarbon-bridged cyclopentadienyl fluorenyl zirconium dichloride, dimethylsilyl-bridged tetramethylcyclopentadienyl tert-butylamino dimethyl titanium, diindenyl zirconium dichloride, methylsilyl (N-tert-butylamino) (tetramethylcyclopentadienyl) titanium dichloride, bis(2-methyl-4,5-phenylindenyl) zirconium dichloride, dicyclopentadienyl zirconium bis(phenoxide), dimethylsilyl-bridged diindenyl zirconium dichloride, diphenylcarbon-bridged cyclopentadienyl-fluorenyl zirconium dichloride, CGC-Ti catalyst, and pyridine amine hafnium catalyst.
  11. The method according to any one of claims 1-9, wherein the ratio of the oligomeric product to the olefin monomer is (0.2-2): 1, preferably (0.3-1): 1.
  12. The method according to any one of claims 1-9, 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 1-9, wherein in step (2), the reaction temperature is 20-180°C, preferably 80-160°C; the pressure is 0.5-4.0MPa, preferably 1.0-3.0 MPa; and the reaction time is 10-200mins, preferably 30-60mins.
  14. Polyolefins obtained by the method according to any one of claims 1-13.

Description

Technical field The present invention relates to a method for preparing polyolefins by cascade polymerization (tandem polymerization), which comprises using a COF supported oligomerization or a homopolymerization catalyst. Background art Polyolefin is one of the most important synthetic materials, accounting for 60% of the total production of synthetic resins, therefore, the development of the polyolefin industry directly affects the national economy. The quality of polyolefin products is mainly controlled by the polymerization technology and process of olefin polymerization. Among them, cascade polymerization is a polymerization reaction that uses two or more catalyst systems that can catalyze different reactions simultaneously. Cascade polymerization has advantages such as avoiding intermediate product separation, storage, transportation, convenience and efficiency etc. However, in the cascade polymerization process, the simultaneous use of two catalysts may lead to mutual influence, manifested intuitively in changes in polymerization activity and copolymer molecular weight. Covalent organic frameworks (COFs) materials are a type of porous two-dimensional or three-dimensional polymer materials with periodic structures connected by covalent bonds, the pore size and skeleton structure thereof can be precisely controlled by monomers and linkage bonds. The uniform and adjustable pore structure of COF provide a uniform and stable chemical environment for the supported catalyst, making it easy to achieve precise control of catalytic performance. Therefore, if COF supported oligomerization or homopolymerization catalysts can be utilized to reduce the mutual influence between oligomerization or homopolymerization catalysts and copolymerization catalysts in cascade polymerization, it will be beneficial for the development of a method for effectively preparing high-performance thermoplastic polyolefin products by cascade polymerization. Detailed description of the invention In the first aspect, the present invention provides a method for preparing polyolefins by cascade polymerization, which comprises the following steps: (1) under anhydrous and anaerobic conditions, ethylene and/or propylene monomers are subjected to oligomerization reaction in a non-polar organic solvent in the presence of a COF supported oligomerization catalyst or a COF supported homopolymerization catalyst, and an optional cocatalyst, to obtain an oligomeric product or macromonomer with terminal double bonds, respectively; and(2) then, under anhydrous and anaerobic conditions, in the presence of an olefin polymerization catalyst, the oligomeric product or macromonomer with terminal double bonds are further polymerized with an olefin monomer in a non-polar organic solvent to obtain the polyolefins. In the above method, the anhydrous and anaerobic conditions refer to the absence of water in the polymerization reaction, and obtaining anaerobic conditions by replacing oxygen in the reactor with inert gases such as nitrogen, argon, helium, and supercritical carbon dioxide and then vacuuming. The COF supported oligomerization catalyst comprises those metallocene catalysts and post metallocene catalysts known as oligomerization catalysts in the art, especially those in which 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 comprise, for example, 1,2,3,4,5-Ph5-Cp/Cr (EH)3, {2-[1-(3H-Ind) CyH] Th} TiCl3, and decamethyl-dicyclopentadiene zirconium dichloride. Examples of the post metallocene catalyst comprise, 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-ButAlCl2) 2, NiBr2 {[2- (3,5-Me2Pyz)] EtA}, V (NAd) Cl2 [8-(2,6-Me2An)-5,6,7-H3Qu], NiBr2[(3,5-Me2Pyz)2PhP], WCl6/2DippNH2/4NEt3, TaCl3 (NDipp) (tmeda), Nb (N-2,6-Prj2Ph) Me2 [2-(2,6-Me2Ph) NCH2 (Pyd)], Ti (OBun) 4, NiCl2 (Bun3P) 2, Cr (acac) 3/Ph2P) 2NPri, Cr (acac) 3/[(o-F-CH) (o-MeOCH) P] 2N (Pri), Cr (CO) 4 [(Ph2P) 2NPrj], [(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 (Prj) Si (CH3) 2CH2Ph2. The SNS-Cr catalyst is compound 1 having the following structural formula: Preferably, the COF supported oligomerization catalyst is selected from Ti (OBun)4, NiCl2 (Bun3P)2, Cr (EH)3/2,5-DMP, Cr (acac)3/[(o-F-CH) (o-MeOCH) P] 2N (Pri), SNS-Cr, PNP/CrCl3 (THF) 3, [(2-Pe-S-Et) 2-A] CrCl3, DPPB/[Cr (H2O) 4Cl2] CI · 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-dicyclopentadiene zirconium dichloride. The COF supported oligomerization catalyst can be prepared by the methods known