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CN-121986121-A - Metallocene-containing catalytic system for the synthesis of polyethylene and copolymers of ethylene with 1, 3-dienes

CN121986121ACN 121986121 ACN121986121 ACN 121986121ACN-121986121-A

Abstract

The present invention relates to a catalytic system based at least on neodymium borohydride, a dialkylzinc compound and an organomagnesium halide of formula RB-Mg-X, wherein RB comprises a benzene ring substituted by two carbon atoms, one of which is substituted by a methyl, ethyl or isopropyl group, or forms a ring with the carbon atom nearest thereto, the second carbon atom is substituted by a methyl, ethyl or isopropyl group, the magnesium atom being located ortho to each of said two carbon atoms, X being a halogen atom. The catalytic system can be used in the homopolymerization of ethylene and the copolymerization of ethylene with 1, 3-diene.

Inventors

  • R grace dagger-axe
  • A. Degrand fever
  • F. Jean Baptiste Dieter Dominic
  • C. Boisson
  • F. Dagusto

Assignees

  • 米其林集团总公司
  • 国家科学研究中心
  • 里昂高等化学物理电子学院
  • 里昂第一大学

Dates

Publication Date
20260505
Application Date
20241001
Priority Date
20231005

Claims (15)

  1. 1. A catalytic system based at least on: the metallocene of the formula (Ia), Organomagnesium halides of the formula (IIa), A dialkyl zinc compound and a salt thereof, {P(Cp 1 )(Cp 2 )Nd(BH 4 ) (1+y)- L y -N x }(Ia) R B -Mg-X(IIa) Cp 1 and Cp 2 are the same or different and are selected from fluorenyl, cyclopentadienyl, and indenyl groups, the groups being substituted or unsubstituted, P is a group bridging the two groups Cp 1 and Cp 2 and containing a silicon or carbon atom, Nd represents a neodymium atom and is represented by, L represents an alkali metal selected from lithium, sodium and potassium, N represents a molecule of an ether and, X is an integer or non-integer equal to or greater than 0, Y is an integer equal to or greater than 0, R B comprises a benzene ring substituted with two carbon atoms, one of which is substituted with a methyl, ethyl or isopropyl group, or forms a ring with the carbon atom nearest thereto, the second carbon atom is substituted with a methyl, ethyl or isopropyl group, a magnesium atom is located ortho to each of the two carbon atoms, X is a halogen atom.
  2. 2. Catalytic system according to claim 1, wherein Cp 1 and Cp 2 are identical and are selected from substituted fluorenyl and unsubstituted fluorenyl of formula C 13 H 8 , preferably Cp 1 and Cp 2 each represent unsubstituted fluorenyl of formula C 13 H 8 .
  3. 3. Catalytic system according to any one of claims 1 to 2, wherein the bridge P of the linking groups Cp 1 and Cp 2 has the formula ZR 1 R 2 , wherein Z represents a silicon or carbon atom, R 1 and R 2 are identical or different and each represent an alkyl group comprising 1 to 20 carbon atoms, preferably a methyl group.
  4. 4. A catalytic system according to any one of claims 1 to 3, wherein the alkyl group of the dialkylzinc compound is an alkyl group comprising 2 to 10 carbon atoms.
  5. 5. The catalytic system of any one of claims 1 to 4, wherein the dialkylzinc compound has the formula (IIIa) ZnR 5 R 6 (IIIa) Wherein the alkyl groups represented by the symbols R 5 and R 6 are identical, preferably ethyl or octyl.
  6. 6. The catalytic system of any one of claims 1 to 5, wherein the organomagnesium halide has formula (IIb) , Wherein X represents a halogen atom, R 1 and R 5 are the same or different and represent a methyl group or an ethyl group, and R 2 、R 3 and R 4 are the same or different and represent a hydrogen atom or an alkyl group.
  7. 7. The catalytic system of claim 6, wherein R 3 is the same as R 1 and R 5 .
  8. 8. The catalytic system of claim 6 or 7, wherein R 1 and R 5 represent methyl.
  9. 9. A catalytic system according to any one of claims 6 to 8, wherein R 2 and R 4 represent hydrogen atoms.
  10. 10. Catalytic system according to any one of claims 1 to 9, wherein X is a bromine atom or a chlorine atom, preferably a bromine atom.
  11. 11. The catalytic system according to any one of claims 1 to 10, wherein the ratio of the moles of Zn in the dialkylzinc compound to the sum of the moles of Zn in the dialkylzinc compound and the moles of Mg in the organomagnesium halide compound is greater than 0.05 and less than 0.99, more preferably greater than 0.3 and less than 0.99.
  12. 12. A process for preparing a polymer, which process comprises subjecting ethylene or a monomer mixture comprising ethylene and a1, 3-diene to a polymerization reaction in the presence of a catalytic system as defined in any one of claims 1 to 11.
  13. 13. The preparation method according to claim 12, wherein the modification reaction is performed after the polymerization reaction using an acid halide, preferably an acid chloride.
  14. 14. The preparation method according to claim 12 or 13, wherein the polymer is polyethylene or a copolymer of ethylene and 1, 3-diene, preferably a statistical copolymer of ethylene and 1, 3-diene.
  15. 15. The preparation process according to any one of claims 12 to 14, wherein the 1, 3-diene is 1, 3-butadiene, isoprene, myrcene, β -farnesene or a mixture thereof, preferably 1, 3-butadiene or a mixture of 1, 3-dienes comprising 1, 3-butadiene.

Description

Metallocene-containing catalytic system for the synthesis of polyethylene and copolymers of ethylene with 1, 3-dienes Technical Field The field of the invention is that of catalytic systems which can be used to prepare polyethylene and ethylene-1, 3-diene copolymers, more particularly those bearing ketone functional groups. Background Highly saturated polymers (e.g., polyethylene rich in ethylene units and diene copolymers) are hydrocarbon-based polymers in nature and have a relatively weak affinity for polar materials, with the result that the field of application of these highly saturated hydrocarbon-based polymers is limited. To increase this affinity, in the case of polyethylene, the introduction of one or more ketone functional groups has been described. For example, the synthesis of copolymers of ethylene and carbon monoxide is widely described, but the synthesis method is not applicable to copolymers of ethylene with alpha-olefins (e.g. 1, 3-dienes) or mixtures of 1, 3-dienes with vinylaromatic compounds. Furthermore, the synthetic method does not selectively lead to the introduction of terminal ketone functionalities. The introduction of a single ketone function at the chain end of the polyethylene is also described. For example, polymer Science, ser. B, vol.46, nos. 9-10, 2004, 308-311 describe the reaction between nitrous oxide and polyethylene with vinyl groups at the chain ends. The introduction of a ketone function at the chain end of the polyethylene results from the oxidation reaction of the double bond of the vinyl group with nitrous oxide. Thus, it can be seen that the synthesis method is not suitable for the chain end selective functionalization of copolymers of ethylene with 1, 3-dienes which also contain double bonds outside the chain ends. For example, the applicant describes in documents WO 2007054223 and WO 2007054224 catalytic systems for the synthesis of ethylene-1, 3-butadiene copolymers comprising neodymium metallocenes and organomagnesium compounds. Organomagnesium compounds are used as cocatalysts in catalytic systems to activate metallocenes for polymerization. The catalytic system is useful in both the synthesis of polyethylene and the synthesis of ethylene-1, 3-diene copolymers. The applicant also describes in document WO 2021123589 variants of these catalytic systems, in which the organomagnesium compound is a compound of formula R B-Mg-RA, R A is a substituted or unsubstituted alkyl, cycloalkyl or benzyl group, R B comprises a benzene ring substituted with two carbon atoms, one of which is substituted with a methyl, ethyl or isopropyl group, or forms a ring with the carbon atom nearest thereto, the second carbon atom being substituted with a methyl, ethyl or isopropyl group, the magnesium atom being located ortho to each of said two carbon atoms. In the course of continuing efforts, the applicant has developed a novel catalytic system which is capable of synthesizing not only copolymers of polyethylene with units comprising ethylene and 1, 3-diene, but also polymers with ketone functional groups, these polymers being copolymers of polyethylene with units comprising ethylene and 1, 3-diene. The ketone functional groups are introduced by reaction of an acid halide with a polymer chain prepared in the presence of the catalytic system according to the invention. Disclosure of Invention Accordingly, the first subject of the present invention is a catalytic system based at least on: the metallocene of the formula (Ia), Organomagnesium halides of the formula (IIa), A dialkyl zinc compound and a salt thereof, {P(Cp1)(Cp2)Nd(BH4)(1+y)-Ly-Nx}(Ia) RB-Mg-X(IIa) Cp 1 and Cp 2 are the same or different and are selected from fluorenyl, cyclopentadienyl, and indenyl groups, the groups being substituted or unsubstituted, P is a group bridging the two groups Cp 1 and Cp 2 and containing a silicon or carbon atom, Nd represents a neodymium atom and is represented by, L represents an alkali metal selected from lithium, sodium and potassium, N represents a molecule of an ether and, X is an integer or non-integer equal to or greater than 0, Y is an integer equal to or greater than 0, R B comprises a benzene ring substituted with two carbon atoms, one of which is substituted with a methyl, ethyl or isopropyl group, or forms a ring with the carbon atom nearest thereto, the second carbon atom is substituted with a methyl, ethyl or isopropyl group, a magnesium atom is located ortho to each of the two carbon atoms, X is a halogen atom. The invention also relates to a process for preparing polymers, which comprises polymerizing ethylene or a monomer mixture comprising ethylene and 1, 3-diene in the presence of the catalytic system according to the invention, where appropriate followed by modification with an acid halide. Detailed Description Any numerical interval represented by the expression "between a and b" represents a numerical range that is greater than "a" and less than "b" (i.e., excluding the