Polyolefin catalytic system for synthesizing ethylene-propylene copolymer and preparation method

Abstract

The invention discloses a polyolefin catalytic system for ethylene-propylene copolymer synthesis, which comprises a solid catalytic component A, ethyl aluminum B and an external electron donor C. The solid catalytic component A is a MgCl2-loaded TiCl4 catalyst solid component, and the MgCl2-loaded TiCl4 catalyst solid component comprises a component containing 2-(2-oxy-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3, 4-trimethyl-1, 3-trimethyl-1, the electron donor is an internal electron donor based on 1, 2-indoline-3-ethyl)-malonic acid diester; the ethyl aluminum B is triethyl aluminum; and the external electron donor C is cyclohexyl methyl dimethoxy silane. The invention solves the problem of low polymerization efficiency caused by low copolymerization performance during polymerization of a MgCl2 supported Z-N catalyst taking aromatic carboxylic acid diester as an internal electron donor in the prior art. The invention also discloses a preparation method of the polyolefin catalytic system.

Description

Technical Field

[0001] The present invention belongs to the technical field of polyolefin catalysts, and relates to a polyolefin catalytic system for the synthesis of ethylene-propylene copolymers. The present invention also relates to a preparation method of the above polyolefin catalytic system. Background Art

[0002] The homopolypropylene prepared by Ziegler-Natta propylene polymerization catalyst has high isotacticity and crystallinity, but the optical properties such as gloss and transparency of the products are poor, which limits its application fields. Usually, the crystalline structure is destroyed by introducing comonomers (ethylene, butene, hexene, etc.) to change its mechanical and optical properties. In recent years, the preparation of ethylene-propylene random copolymer polypropylene with ethylene as the second monomer has become a research hotspot.

[0003] Regarding the preparation of ethylene-propylene copolymer products, more attention has been paid to production processes. For example, Chinese patent "An aluminized propylene-butene copolymer polypropylene cast film material and its preparation method" (Publication date: April 1, 2015, Publication number: CN104479228A), Chinese patent "Transparent polypropylene resin and its preparation method" (Publication date: November 9, 2016, Publication number: CN106084488A), and Chinese patent "A gas-phase process propylene-butene random copolymer polypropylene production device and method" (Publication date: November 2, 2021, Publication number: CN113583167A) respectively improve the production of ethylene-propylene copolymers from processes such as Spheripol, Spherizone, Inovene or Unipol.

[0004] The catalyst system for the preparation of ethylene-propylene copolymers includes a main catalyst, an internal electron donor, ethyl aluminum and an external electron donor. At present, there are few reports on the optimization and improvement of the catalyst system for the production of ethylene-propylene copolymers. The catalysts for industrial production of polypropylene are mainly MgCl2-supported Z-N catalysts with aromatic carboxylic acid diesters as internal electron donors. However, such catalysts have low copolymerization performance during polymerization, resulting in low conversion rate of comonomers and low polymerization efficiency. Summary of the Invention

[0005] The object of the present invention is to provide a polyolefin catalytic system for the synthesis of ethylene-propylene copolymers, which solves the problem that the MgCl2-supported Z-N catalyst with aromatic carboxylic acid diesters as internal electron donors has low polymerization efficiency due to low copolymerization performance during polymerization in the prior art.

[0006] Another object of the present invention is to provide a preparation method of a polyolefin catalytic system.

[0007] The technical solution adopted by the present invention is a polyolefin catalyst system for the synthesis of ethylene-propylene copolymer, which comprises a solid catalyst component A, ethylaluminum B, and an external electron donor C. Among them, the solid catalyst component A is a solid component of a TiCl4 catalyst supported on MgCl2, and the solid component of the TiCl4 catalyst supported on MgCl2 includes an internal electron donor containing 2-(2-oxo-1,2-dihydroindol-3-yl)ethyl malonate; the ethylaluminum B is triethylaluminum; and the external electron donor C is cyclohexylmethyldimethoxysilane.

[0008] The internal electron donor containing 2-(2-oxo-1,2-dihydroindol-3-yl)ethyl malonate is a compound of formula (I):

[0009]

[0010] Among them, R1, R2, R3, and R4 are the same or different; R1 is selected from one or more of halogen, linear or branched C1-C 10 alkyl chains, C1-C 10 alkoxy groups, C6-C 20 aryl groups;

[0011] R2 and R3 are selected from any one of linear or branched C1-C 10 alkyl chains; R4 is selected from linear or branched C1-C 10 alkyl chains, C1-C 10 alkylbenzenes, C1-C 10 alkanoyl groups.

[0012] The molar ratio of Al / Ti in the solid catalyst component A and the ethylaluminum B is 100-1000 / 1, and the molar ratio of the external electron donor C to Ti in the solid catalyst component A is 5-100 / 1.

[0013] The internal electron donor in the solid catalytic component A is selected from: diethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-ethyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-propyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-butyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-isopropyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-tert-butyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-isobutyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-phenyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-acetyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-formyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-cyclopentyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-cyclohexyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, dimethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl ethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl propyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl n-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl isopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, ethyl isopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diisopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl n-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, ethyl tert-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl n-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-phenyl-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-benzyl-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,6-diphenyl-1-methyl-2-oxo-1,Di-tert-butyl 2-(1,4-dimethyl-5-phenyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(1,4-dimethyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(1,4-dimethoxy-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4-iodo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(6-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(6-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(6-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(6-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(7-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(7-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(7-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(7-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,5-difluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,5-dichloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,5-dibromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,5,Di-tert-butyl 2-(6-trichloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, dimethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl ethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl propyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl n-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl isopropyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, ethyl isopropyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, diisopropyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, ethyl tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, isopropyl tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(1-benzyl-4-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-iodo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-methoxy-1-benzyl-2-oxo-1,One or a mixture of two or more of di-tert-butyl 2-(indolin-2-yl-3-yl)malonate, di-tert-butyl 2-(6-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(6-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(6-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(6-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(7-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(7-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(7-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(7-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,5-difluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,5-dichloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,5-dibromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,5,6-trichloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate.,

[0014] The second technical solution adopted by the present invention is a preparation method of a polyolefin catalyst system. To prepare the above polyolefin catalyst system, it is specifically implemented according to the following steps:

[0015] Step 1: Prepare a solid catalyst component A, that is, prepare a MgCl₂-supported TiCl₄ catalyst solid component;

[0016] Step 2: Mix the prepared MgCl₂-supported TiCl₄ catalyst solid component with ethylaluminum B and external electron donor C to form a polyolefin catalyst system, wherein ethylaluminum B is triethylaluminum; external electron donor C is cyclohexylmethyldimethoxysilane.

[0017] The feature of the second technical solution of the present invention also lies in that

[0018] In Step 1, the solid component of the MgCl₂-supported TiCl₄ catalyst is prepared specifically according to the following steps:

[0019] Step 1.1: Pour 10 - 50 equiv of anhydrous MgCl₂ into a three-necked flask fully purged with nitrogen, then add 50 - 150 ml of decane and 50 - 150 ml of isooctanol. While stirring, heat the mixture to 130 - 200 °C and react at this temperature for 3 hours. Then add 1 equiv of tetrabutyl titanate and continue to react at 130 °C for 1 - 12 hours. After the reaction is completed, cool the mixture to room temperature to obtain a stable and homogeneous alcoholate solution;

[0020] Step 1.2: Dropwise add the alcoholate solution obtained in Step 1.1 over 1 hour into a reactor fully purged with nitrogen and containing 200 - 500 ml of titanium tetrachloride at -20 to 0 °C. After the dropwise addition is completed, heat the mixture to 80 - 150 °C over 1 - 24 hours. Then add 10 - 50 equiv of an internal electron donor containing 2-(2-oxo-1,2-dihydroindol-3-yl)ethyl malonate diester, and continue to heat for 30 - 50 min until the temperature reaches 100 - 150 °C. React at this temperature for 1 - 3 hours. After the reaction is completed, filter the liquid, and then re-add 100 - 500 ml of titanium tetrachloride at -80 °C and react at 110 °C for 2 hours. After the reaction is completed, filter out the reaction solution;

[0021] Step 1.3: Hot wash the reaction solution obtained in the previous step 5 - 12 times with hexane dried by molecular sieve. The remaining solid product is vacuum dried to obtain the solid component of the MgCl₂-supported TiCl₄ catalyst, which is the solid catalytic component A;

[0022] In Step 2, the molar ratio of Al / Ti in the solid catalytic component A and ethylaluminum B is 100 - 1000 / 1, and the molar ratio of the external electron donor C to Ti in the solid catalytic component A is 5 - 100 / 1.

[0023] The internal electron donor containing 2-(2-oxo-1,2-dihydroindol-3-yl)ethyl malonate diester is a compound with the structure of formula (I):

[0024]

[0025] Among them, R₁, R₂, R₃, and R₄ are the same or different; R₁ is selected from one or more of halogen, linear or branched C₁-C 10 alkyl chains, C₁-C 10 alkoxy groups, C₆-C 20 aryl groups;

[0026] R₂ and R₃ are selected from linear or branched C₁-C 10any one of the linear alkyl groups; R4 is selected from linear or branched C1-C 10 linear alkyl groups, C1-C 10 alkylbenzenes, C1-C 10 any one of the alkanoyl groups.

[0027] The internal electron donor in the solid catalytic component A is selected from: diethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, diethyl 2-(1-ethyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, diethyl 2-(1-propyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, diethyl 2-(1-butyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, diethyl 2-(1-isopropyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, diethyl 2-(1-tert-butyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, diethyl 2-(1-isobutyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, diethyl 2-(1-phenyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, diethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, diethyl 2-(1-acetyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, diethyl 2-(1-formyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, diethyl 2-(1-cyclopentyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, diethyl 2-(1-cyclohexyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, dimethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, methyl ethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, methyl propyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, methyl n-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, methyl isopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, ethyl isopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, diisopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, methyl n-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, ethyl tert-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, methyl n-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, di-tert-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, di-tert-butyl 2-(5-phenyl-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, di-tert-butyl 2-(5-benzyl-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, di-tert-butyl 2-(4,6-diphenyl-1-methyl-2-oxo-1,Di-tert-butyl 2-(1,4-dimethyl-5-phenyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(1,4-dimethyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(1,4-dimethoxy-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4-iodo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(6-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(6-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(6-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(6-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(7-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(7-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(7-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(7-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,5-difluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,5-dichloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,5-dibromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,5,Di-tert-butyl 2-(6-trichloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, dimethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl ethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl propyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl n-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl isopropyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, ethyl isopropyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, diisopropyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, ethyl tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, isopropyl tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(1-benzyl-4-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-iodo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-methoxy-1-benzyl-2-oxo-1,One or a mixture of two or more of di-tert-butyl 2-(2,3-dihydroindol-3-yl)malonate, di-tert-butyl 2-(6-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(6-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(6-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(6-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(7-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(7-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(7-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(7-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,5-difluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,5-dichloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,5-dibromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,5,6-trichloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate.,

[0028] In step 1.2, the internal electron donor containing 2-(2-oxo-1,2-dihydroindol-3-yl)malonates is specifically prepared according to the following method:

[0029] Step 1.2.1: In a 100-250 mL round-bottom flask, add 1 equiv of isatin compound, dissolve it in 20-50 mL of dry ethanol solvent, add 5-30 equiv of malonate and 0.2-1 equiv of piperidine as a catalyst. Then, install a reflux condenser on the reaction system and heat it to the reflux temperature in an oil bath for about 2 h. After monitoring the reaction to completion by TLC, cool the system to room temperature to precipitate a solid. Then, filter the obtained solid and wash it with 10-50 mL of cold ethanol solution in small portions multiple times to obtain an analytically pure compound;

[0030] Step 1.2.2: Dissolve the analytical pure compound obtained in Step 1.2.1 in 10 - 50 mL of DMF solvent, slowly add 1.0 - 10.0 equiv of solid base, and dropwise add 1.0 - 10.0 equiv of liquid bromo protecting group R1. The reaction system is left overnight at room temperature. After monitoring the reaction to completion by TLC, quench the reaction with water, extract with 50 - 250 mL of dichloromethane at least 3 times, combine the organic phases, then wash multiple times with saturated brine, dry over anhydrous magnesium sulfate, filter off the desiccant, and evaporate the solvent under reduced pressure. The residue is the crude product of the prepared compound.

[0031] Step 1.2.3: Separate the crude product obtained in Step 1.2.2 by silica gel column chromatography with a petroleum ether:ethyl acetate ratio of 32:1 - 2:1 V / V to obtain the corresponding diester - oxindole compound, which is an orange - red solid, i.e., an internal electron donor containing 2 - (2 - oxo - 1,2 - dihydroindol - 3 - yl) - ethyl malonate.

[0032] The third technical solution adopted in the present invention is the use of a polyolefin catalyst system. Using the polyolefin catalyst system prepared by the above method for ethylene - propylene copolymerization to obtain an ethylene - propylene copolymer, specifically:

[0033] Heat and evacuate the high - pressure reactor to remove air and water, displace with nitrogen at least 3 times repeatedly, then add 10 - 50 equiv of the solid component of the MgCl2 - supported TiCl4 catalyst, triethylaluminum, and the external electron donor cyclohexylmethyldimethoxysilane to the high - pressure reactor. Then add 100 - 500 mmol of hydrogen, 1 - 2 kg of propylene, and 100 - 500 g of ethylene. Close the reactor, raise the reactor temperature to 40 - 45 °C, start the polymerization. After reacting for 2 - 5 h, discharge the unreacted olefin monomers to obtain an ethylene - propylene copolymer.

[0034] The molar ratio of Al / Ti in the MgCl2 - supported TiCl4 catalyst solid and triethylaluminum is 100 - 1000 / 1, and the molar ratio of cyclohexylmethyldimethoxysilane to Ti in the MgCl2 - supported TiCl4 catalyst solid is 5 - 100 / 1.

[0035] The beneficial effects of the present invention are:

[0036] The polyolefin catalyst system for ethylene - propylene copolymer synthesis in the present invention can improve the hydrogen response sensitivity and polymerization efficiency of the catalyst, i.e., the activity of the catalyst, by introducing a highly active and electron - cloud - enriched oxindole structure, thereby improving the copolymerization performance of propylene and other olefins, and obtaining an ethylene - propylene random copolymer polypropylene with a more uniform comonomer distribution, better transparency, and processability.

[0037] The preparation method of the polyolefin catalyst system of the present invention is simple, providing a preparation basis for the polyolefin catalyst system for the synthesis of ethylene-propylene copolymers of the present invention. Detailed Embodiments

[0038] The present invention will be described in detail below in conjunction with the specific embodiments.

[0039] Example 1

[0040] A polyolefin catalyst system for the synthesis of ethylene-propylene copolymers, comprising a solid catalyst component A, triethylaluminum B, and an external electron donor C. Among them, the solid catalyst component A is a MgCl2-supported TiCl4 catalyst solid component, and the MgCl2-supported TiCl4 catalyst solid component includes an internal electron donor containing 2-(2-oxo-1,2-dihydroindol-3-yl)ethyl malonate; triethylaluminum B is triethylaluminum; and the external electron donor C is cyclohexylmethyldimethoxysilane.

[0041] Example 2

[0042] The preparation method of the polyolefin catalyst system of the present invention for preparing the above polyolefin catalyst system is specifically implemented according to the following steps:

[0043] Step 1, preparing the solid catalyst component A, that is, preparing the MgCl2-supported TiCl4 catalyst solid component;

[0044] Step 2, mixing the prepared MgCl2-supported TiCl4 catalyst solid component with triethylaluminum B and the external electron donor C to form a polyolefin catalyst system, where triethylaluminum B is triethylaluminum; and the external electron donor C is cyclohexylmethyldimethoxysilane.

[0045] The MgCl2-supported TiCl4 catalyst solid component in Step 1 is specifically prepared according to the following steps:

[0046] Step 1.1, pouring 10 - 50 equiv of anhydrous MgCl2 into a three-necked flask fully replaced with nitrogen, then adding 50 - 150 ml of decane and 50 - 150 ml of isooctanol, heating to 130 - 200 °C while stirring and reacting for 3 hours at this temperature, then adding 1 equiv of tetrabutyl titanate and continuing to react at 130 °C for 1 - 12 hours. After the reaction is completed, cool to room temperature to obtain a stable and uniform alcoholate solution;

[0047] Step 1.2: The obtained alcoholate solution in Step 1.1 is added dropwise for 1 hour and completely added dropwise to a reactor that has been fully replaced with nitrogen and contains 200 - 500 ml of titanium tetrachloride at -20 to 0 °C. After the addition is complete, the temperature is raised to 80 - 150 °C over 1 - 24 hours, and then 10 - 50 equiv of an internal electron donor containing 2-(2-oxo-1,2-dihydroindol-3-yl)ethyl malonate is added. The temperature is further raised for 30 - 50 min until it reaches 100 - 150 °C, and the reaction is carried out at this temperature for 1 - 3 hours. After the reaction ends and the liquid is filtered, 100 - 500 ml of titanium tetrachloride (RT - 80 °C) is added again, and the reaction is carried out at 110 °C for 2 hours. After the reaction ends, the reaction solution is filtered out;

[0048] Step 1.3: The reaction solution obtained in the previous step is washed with hexane dried by molecular sieve 5 - 12 times while hot, and the remaining solid product is dried under vacuum to obtain the solid component of the MgCl₂-supported TiCl₄ catalyst, which is the solid catalytic component A;

[0049] In Step 2, the molar ratio of Al / Ti in the solid catalytic component A and ethylaluminum B is 100 - 1000 / 1, and the molar ratio of the external electron donor C to Ti in the solid catalytic component A is 5 - 100 / 1.

[0050] The internal electron donor containing 2-(2-oxo-1,2-dihydroindol-3-yl)ethyl malonate in Step 1.2 is specifically prepared according to the following method:

[0051] Step 1.2.1: In a 100 - 250 mL round-bottom flask, 1 equiv of isatin compound is added, dissolved in 20 - 50 mL of dry ethanol solvent, 5 - 30 equiv of malonate and 0.2 - 1 equiv of piperidine are added as a catalyst. Then, a reflux condenser is installed in the reaction system, and the reaction is heated to the reflux temperature in an oil bath for about 2 h. After the reaction is completely monitored by TLC, the system is cooled to room temperature, and a solid precipitates. Then, the obtained solid is filtered and washed with 10 - 50 mL of cold ethanol solution in small portions multiple times to obtain an analytically pure compound. The reaction process is as shown in the reaction process of the first arrow in Chemical Formula II;

[0052] Step 1.2.2: Dissolve the analytical pure compound obtained in Step 1.2.1 in 10 - 50 mL of DMF solvent, slowly add 1.0 - 10.0 equiv of solid base, and dropwise add 1.0 - 10.0 equiv of liquid bromo-protecting group R1. The reaction system is left overnight at room temperature. After monitoring the completion of the reaction by TLC, quench the reaction with water, extract with 50 - 250 mL of dichloromethane at least 3 times, combine the organic phases, then wash with saturated brine multiple times, dry over anhydrous magnesium sulfate, filter off the desiccant, and evaporate the solvent under reduced pressure. The residue is the crude product of the prepared compound, and the reaction process is as shown in the reaction process of the second arrow in Chemical Formula II;

[0053] Step 1.2.3: Separate the crude product obtained in Step 1.2.2 by silica gel column chromatography with a petroleum ether:ethyl acetate ratio of 32:1 - 2:1 V / V to obtain the corresponding diester-based oxindole compound, which is an orange-red solid, namely the internal electron donor containing 2-(2-oxo-1,2-dihydroindol-3-yl)ethyl-malonic acid diester, which is the product of Chemical Formula II.

[0054]

[0055] Synthesize the new compound 3-1i according to Synthesis Steps 1.2.1 - 1.2.3 with a yield of 75%.

[0056]

[0057] 1H NMR(CDCl3, 400 MHz): δ8.37(d, J = 7.6 Hz, 1H), 7.32 - 7.23(m, 6H), 6.99(t, J = 7.6 Hz, 1H), 6.66(d, J = 7.6 Hz, 1H), 4.89(s, 2H), 4.47(q, J = 7.2 Hz, 2H), 4.38(q, J = 7.2 Hz, 2H), 1.42 - 1.35(m, 6H); 13C NMR(CDCl3, 100 MHz): δ166.0, 165.3, 162.9, 145.1, 135.0, 134.1, 132.9, 129.6, 128.72, 128.67, 127.7, 127.2, 122.8, 119.1, 109.3, 62.2, 62.1, 43.6, 13.9, 13.8.

[0058] Use the polyolefin catalyst system prepared by the present invention to carry out ethylene-propylene copolymerization to obtain an ethylene-propylene copolymer, specifically:

[0059] Heat the autoclave under high pressure and evacuate it to remove air and water. Replace the air with nitrogen at least three times. Then, add 10 - 50 equiv of the solid component of the MgCl₂-supported TiCl₄ catalyst, triethylaluminum, and the external electron donor cyclohexylmethyldimethoxysilane to the autoclave. Next, add 100 - 500 mmol of hydrogen, 1 - 2 kg of propylene, and 100 - 500 g of ethylene. Close the autoclave, raise the temperature of the autoclave to 40 - 45 °C, and start the polymerization. After reacting for 2 - 5 h, discharge the unreacted olefin monomers to obtain the ethylene-propylene copolymer.

[0060] The molar ratio of Al / Ti in the MgCl₂-supported TiCl₄ catalyst solid and triethylaluminum is 100 - 1000 / 1, and the molar ratio of cyclohexylmethyldimethoxysilane to Ti in the MgCl₂-supported TiCl₄ catalyst solid is 5 - 100 / 1.

[0061] Example 3

[0062] On the basis of Example 1 and Example 2, the internal electron donor containing 2-(2-oxo-1,2-dihydroindol-3-yl)ethyl malonate is a compound with the structure of formula (I):

[0063]

[0064] Among them, R1, R2, R3, and R4 are the same or different;

[0065] R1 is selected from one or more of halogen (F, Cl, Br, I), straight-chain or branched C1-C 10 alkyl chain, C1-C 10 alkoxy group, C6-C 20 aryl group;

[0066] R2 and R3 are selected from any one of straight-chain or branched C1-C 10 alkyl chain; R4 is selected from any one of straight-chain or branched C1-C 10 alkyl chain, C1-C 10 alkylbenzene, C1-C 10 alkanoyl group;

[0067] Among them, "C1-C 10 alkyl chain" refers to an alkyl chain group with 1 - 10 carbon atoms in total, including straight-chain and branched alkyl chain groups. For example, it includes, but is not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, pentyl and its various isomers (such as n-pentyl, isopentyl, neopentyl, etc.), hexyl and its various isomers (such as n-hexyl, isohexyl, etc.), heptyl and its various isomers, octyl and its various isomers, nonyl and its various isomers, and decyl and its various isomers.

[0068] “C1-C 10 "C1-C alkylbenzene" refers to a phenyl group substituted by a chain alkyl group with a total number of carbon atoms of 1-10, including straight-chain and branched-chain alkyl groups. For example, it includes, but is not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, pentyl and its various isomers (such as n-pentyl, isopentyl, neopentyl, etc.), hexyl and its various isomers (such as n-hexyl, isohexyl, etc.), heptyl and its various isomers, octyl and its various isomers, nonyl and its various isomers, and decyl and its various isomers substituted phenyl group compounds.

[0069] “C1-C 10 "C1-C alkanoyl" refers to an acyl group substituted by a chain alkyl group with a total number of carbon atoms of 1-10, including straight-chain and branched-chain alkyl groups. For example, it includes, but is not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, pentyl and its various isomers (such as n-pentyl, isopentyl, neopentyl, etc.), hexyl and its various isomers (such as n-hexyl, isohexyl, etc.), heptyl and its various isomers, octyl and its various isomers, nonyl and its various isomers, and decyl and its various isomers substituted acyl group compounds.

[0070] Preferably, R1 can be any one or more of C1-C chain alkyl, C1-C alkoxy, halogen (F, Cl, Br, I); R2 and R3 are each independently selected from any one of straight-chain and branched-chain alkyl groups of C3-C8; R4 is any one of C1-C chain alkyl, C1-C alkylbenzene. 10 of the chain alkyl, C1-C 10 alkoxy, halogen (F, Cl, Br, I); R2, R3 are each independently selected from any one of straight-chain and branched-chain alkyl groups of C3-C8; R4 is any one of C1-C 10 of the chain alkyl, C1-C 10 alkylbenzene.

[0071] More preferably, R1 is C1-C 10 alkoxy, halogen (F, Cl, Br, I); R2, R 3、 R4 are each independently selected from, for example: any one of isopropyl, tert-butyl, isobutyl, phenyl, methylphenyl, isopropylphenyl.

[0072] The molar ratio of Al / Ti in the solid catalytic component A and ethylaluminum B is 100-1000 / 1, and the molar ratio of the external electron donor C to Ti in the solid catalytic component A is 5-100 / 1.

[0073] The internal electron donor in the solid catalytic component A is selected from: diethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-ethyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-propyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-butyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-isopropyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-tert-butyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-isobutyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-phenyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-acetyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-formyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-cyclopentyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-cyclohexyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, dimethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl ethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl propyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl n-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl isopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, ethyl isopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diisopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl n-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, ethyl tert-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl n-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-phenyl-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-benzyl-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,6-diphenyl-1-methyl-2-oxo-1,Di-tert-butyl 2-(1,4-dimethyl-5-phenyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(1,4-dimethyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(1,4-dimethoxy-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4-iodo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(5-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(5-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(5-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(5-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(6-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(6-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(6-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(6-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(7-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(7-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(7-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(7-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4,5-difluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4,5-dichloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4,5-dibromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4,5,Di-tert-butyl 2-(6-trichloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, dimethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl ethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl propyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl n-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl isopropyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, ethyl isopropyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, diisopropyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, ethyl tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, isopropyl tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(1-benzyl-4-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-iodo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-methoxy-1-benzyl-2-oxo-1,One or a mixture of two or more of di-tert-butyl 2-(2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(6-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(6-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(6-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(6-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(7-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(7-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(7-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(7-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,5-difluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,5-dichloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,5-dibromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,5,6-trichloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,6-dichloro-5-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,6-dichloro-5-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,6-dichloro-5-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate.,

[0074] Examples 4 to 6 are specific examples of the internal electron donors containing 2-(2-oxo-1,2-dihydroindol-3-yl)ethyl diesters of the present invention, which are as follows:

[0075] Example 4

[0076] In a 100 mL round-bottom flask, 1.0 g of indigo compound (5 mmol, 1.0 equiv) was added and dissolved in 20 mL of dry ethanol solvent. Diethyl malonate (10 mol) was slowly added, along with two drops of piperidine as a catalyst. Then, a reflux condenser was installed for the reaction system, and it was heated to the reflux temperature in an oil bath and reacted for about 2 h. After the reaction was completely monitored by TLC, the system was cooled to room temperature, and a solid precipitated. Then, the obtained solid was filtered and washed with a small amount of cold ethanol solution (10 mL) multiple times to obtain an analytically pure compound. Subsequently, the obtained solid was dissolved in 15 mL of DMF solvent, potassium carbonate solid (1.2 mmol) was slowly added, and benzyl bromide liquid (1.2 mmol) was added dropwise. The reaction system was left overnight at room temperature. After the reaction was completely monitored by TLC, the reaction was quenched with water, extracted with dichloromethane (50 mL × 3), the organic phases were combined, washed multiple times with saturated brine, dried over anhydrous magnesium sulfate, the desiccant was filtered off, the solvent was evaporated under reduced pressure, and the residue was the crude product of the prepared compound. Then, it was separated by silica gel column chromatography (petroleum ether:ethyl acetate = 16:1, V / V) to obtain the corresponding diethyl ester-based oxindole compound, which was an orange-red solid. This step can synthesize diethyl ester-based oxindole derivatives of indigo or indigo derivatives with substituents on the benzene ring.

[0077] Example 5

[0078] In a 100 mL round-bottom flask, 1.0 g of 5-methyl indigo compound (5 mmol, 1.0 equiv) was added and dissolved in 20 mL of dry ethanol solvent. Dimethyl malonate (10 mol) was slowly added, along with two drops of piperidine as a catalyst. Then, a reflux condenser was installed for the reaction system, and it was heated to the reflux temperature in an oil bath and reacted for about 2 h. After the reaction was completely monitored by TLC, the system was cooled to room temperature, and a solid precipitated. Then, the obtained solid was filtered and washed with a small amount of cold ethanol solution (10 mL) multiple times to obtain an analytically pure compound. Subsequently, the obtained solid was dissolved in 15 mL of DMF solvent, cesium carbonate solid (1.2 mmol) was slowly added, and methyl iodide liquid (1.2 mmol) was added dropwise. The reaction system was left overnight at room temperature. After the reaction was completely monitored by TLC, the reaction was quenched with water, extracted with dichloromethane (50 mL × 3), the organic phases were combined, washed multiple times with saturated brine, dried over anhydrous magnesium sulfate, the desiccant was filtered off, the solvent was evaporated under reduced pressure, and the residue was the crude product of the prepared compound. Then, it was separated by silica gel column chromatography (petroleum ether:ethyl acetate = 16:1, V / V) to obtain the corresponding dimethyl ester-based oxindole compound, which was an orange-red solid. This step can synthesize dimethyl ester-based oxindole derivatives of indigo derivatives with substituents on the benzene ring.

[0079] Example 6

[0080] In a 100 mL round-bottom flask, 1.0 g of isatin compound (5 mmol, 1.0 equiv) was added and dissolved in 20 mL of dry ethanol solvent. Diisopropyl malonate (10 mol) was slowly added, along with two drops of piperidine as a catalyst. Then, a reflux condenser was installed in the reaction system, and the mixture was heated to the reflux temperature in an oil bath and reacted for about 2 h. After the reaction was completely monitored by TLC, the system was cooled to room temperature, and a solid was precipitated. Then, the obtained solid was filtered and washed with a small amount of cold ethanol solution (10 mL) multiple times to obtain an analytically pure compound. Then, the obtained solid was dissolved in 15 mL of DMF solvent, potassium carbonate solid (1.2 mmol) was slowly added, and acetyl chloride liquid (1.2 mmol) was added dropwise. The reaction system was left overnight at room temperature. After the reaction was completely monitored by TLC, the reaction was quenched by adding water, and extraction was carried out with dichloromethane (50 mL × 3). The organic phases were combined, washed with saturated brine multiple times, dried over anhydrous magnesium sulfate, the desiccant was filtered off, and the solvent was evaporated under reduced pressure. The residue was the crude product of the prepared compound. Then, silica gel column chromatography separation (petroleum ether:ethyl acetate = 16:1, V / V) was carried out to obtain the corresponding diisopropyl malonate-oxindole compound, which was an orange-red solid. This step can synthesize isatin or diisopropyl malonate-oxindole derivatives with substituents on the benzene ring.

[0081] Examples 7-24 are examples of preparing the solid component of the MgCl2-supported TiCl4 catalyst and synthesizing ethylene-propylene copolymers in the present invention. Among them, the ethylene content of the ethylene-propylene copolymer was tested by infrared according to the enterprise standard. The melt index of the ethylene-propylene copolymer was determined according to the test standard ASTM D1238, and the experimental conditions were 2.16 Kg and 230 °C. The haze of the ethylene-propylene copolymer was tested according to GB / T 2410.2-2008 using the integrating sphere accessory of the ultraviolet spectrophotometer UV-2600, as follows:

[0082] Example 7

[0083] 10 g of anhydrous MgCl2 was poured into a three-necked flask fully replaced with nitrogen, 50 ml of decane and 50.0 ml of isooctanol were added, and the temperature was raised to 130 °C with stirring and reacted at this temperature for 3 h. 3.0 g of tetrabutyl titanate was added, and the reaction continued at 130 °C for 1 h. After the reaction was completed, it was cooled to room temperature to obtain a stable and uniform alcoholate solution.

[0084] The prepared homogeneous solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20 °C that had been thoroughly purged with nitrogen over 1 hour. After the addition was complete, the temperature was raised to 80 °C over 3 hours. Then, 10 g of diethyl 2-(2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was added, and the temperature was further raised for 30 min until it reached 110 °C. The reaction was carried out at this temperature for 2 hours. After the reaction ended and the liquid was filtered, 200 ml of titanium tetrachloride was added again, and the reaction was carried out at 110 °C for 2 hours. After the reaction ended, the reaction solution was filtered out, and the remaining solid product was washed 6 times with hexane dried by molecular sieve under heat. The solid catalyst was obtained by vacuum drying. Its titanium content was 3.5 wt%, and the content of diethyl 2-(2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was 6.0 wt%.

[0085] A 5 L high-pressure reactor was heated and evacuated to remove air and water, and then purged with nitrogen three times. Then, 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (the internal electron donor was diethyl 2-(2-oxo-1,2-dihydroindol-3-yl)ethylmalonate) was added. The amount of triethylaluminum added was Al / Ti (molar ratio) = 500. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in molar ratio to Ti. Then, 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reactor was closed, the temperature of the reactor was raised to 40 °C, and polymerization started. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 14.0 KgPol / g catalyst. The melting point of the ethylene-propylene copolymer was 139.2 °C, the melt flow rate was 58.3 gPP / 10 min, the ethylene content was 2.13 mol%, the haze was 17.8%, the tensile yield stress was 37 MPa, the flexural modulus was 1889 MPa, and the impact strength was 2.2 KJ / m 2 。

[0086] Example 8

[0087] 10 g of anhydrous MgCl2 was poured into a three-necked flask that had been thoroughly purged with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The mixture was stirred and heated to 130 °C, and the reaction was carried out at this temperature for 3 hours. Then, 3.0 g of tetrabutyl titanate was added, and the reaction was continued at 130 °C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and homogeneous alcoholate solution.

[0088] The prepared uniform solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20°C that had been fully purged with nitrogen over 1 hour. After the addition was complete, the temperature was raised to 80°C over 3 hours. Then, 20 g of diethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was added, and the temperature was further raised for 30 min until it reached 110°C. The reaction was carried out at this temperature for 2 hours. After the reaction ended, the liquid was filtered, and 200 ml of titanium tetrachloride was added again. The reaction was carried out at 110°C for 2 hours. After the reaction ended, the reaction solution was filtered out and washed 6 times with hot hexane dried by molecular sieve. The remaining solid product was dried under vacuum to obtain a solid catalyst. Its titanium content was 6.8 wt%, and the content of diethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was 13.2 wt%.

[0089] A 5 L high-pressure reactor was heated and evacuated to remove air and water, and then purged with nitrogen three times. Then, 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (with 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate as the internal electron donor) was added. The amount of triethylaluminum added was Al / Ti (molar ratio) = 300. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in molar ratio to Ti. Then, 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reactor was closed, the temperature of the reactor was raised to 40°C, and polymerization began. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 19.0 KgPol / g catalyst. The melting point of the ethylene-propylene copolymer was 135.2°C, the melt flow rate was 56.3 gPP / 10 min, the ethylene content was 2.53 mol%, the haze was 12.6%, the tensile yield stress was 32 MPa, the flexural modulus was 1532 MPa, and the impact strength was 3.7 KJ / m 2 。

[0090] Example 9

[0091] 10 g of anhydrous MgCl2 was poured into a three-necked flask that had been fully purged with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The mixture was stirred and heated to 130°C, and the reaction was carried out at this temperature for 3 hours. Then, 3.0 g of tetrabutyl titanate was added, and the reaction was continued at 130°C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and uniform alcoholate solution.

[0092] The above-prepared homogeneous solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20 °C that had been fully replaced with nitrogen over 1 hour. After the addition was complete, the temperature was raised to 80 °C over 3 hours. 15 g of diethyl 2-(1-isopropyl-2-oxido-1,2-dihydroindol-3-yl)ethylmalonate was added, and the temperature was further raised for 30 min until it reached 110 °C. The reaction was carried out at this temperature for 2 hours. After the reaction ended and the liquid was filtered, 200 ml of titanium tetrachloride was added again, and the reaction was carried out at 110 °C for 2 hours. After the reaction ended, the reaction solution was filtered out, hot washed 6 times with hexane dried by molecular sieve, and the remaining solid product was dried under vacuum to obtain a solid catalyst. Its titanium content was 5.9 wt%, and the content of diethyl 2-(1-isopropyl-2-oxido-1,2-dihydroindol-3-yl)ethylmalonate was 9.5 wt%.

[0093] A 5 L high-pressure reactor was heated and evacuated to remove air and water, replaced with nitrogen three times repeatedly, and then 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (the internal electron donor was diethyl 2-(1-isopropyl-2-oxido-1,2-dihydroindol-3-yl)ethylmalonate) was added. The amount of triethylaluminum added was Al / Ti (molar ratio) = 400. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in molar ratio to Ti. Then 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reactor was closed, the reactor temperature was raised to 40 °C, and polymerization began. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 12.0 KgPol / g catalyst. The melting point of the ethylene-propylene copolymer was 138.5 °C, the melt flow rate was 59.1 gPP / 10 min, the ethylene content was 1.83 mol%, the haze was 21%, the tensile yield stress was 31 MPa, the flexural modulus was 1538 MPa, and the impact strength was 1.9 KJ / m 2 。

[0094] Example 10

[0095] 10 g of anhydrous MgCl2 was poured into a three-necked flask that had been fully replaced with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The temperature was raised to 130 °C while stirring, and the reaction was carried out at this temperature for 3 hours. 3.0 g of tetrabutyl titanate was added, and the reaction was continued at 130 °C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and homogeneous alcoholate solution.

[0096] The above-prepared uniform solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20°C that had been fully purged with nitrogen over 1 hour. After the addition was complete, the temperature was raised to 80°C over 3 hours. 10 g of diethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was added, and the temperature was further raised for 30 min until it reached 110°C. The reaction was carried out at this temperature for 2 hours. After the reaction ended, the liquid was filtered, 200 ml of titanium tetrachloride was added again, and the reaction was carried out at 110°C for 2 hours. After the reaction ended, the reaction solution was filtered out, and it was hot-washed 6 times with hexane dried by molecular sieve. The remaining solid product was dried under vacuum to obtain a solid catalyst. Its titanium content was 3.8 wt%, and the content of diethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was 6.5 wt%.

[0097] A 5 L high-pressure reactor was heated and evacuated to remove air and water, and then purged with nitrogen three times repeatedly. Then, 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (the internal electron donor was diethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate) was added. The amount of triethylaluminum added was Al / Ti (molar ratio) = 500. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in terms of the molar ratio to Ti. Then, 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reaction kettle was closed, the kettle temperature was raised to 40°C, and polymerization was started. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 19.2 KgPol / g catalyst. The melting point of the ethylene-propylene copolymer was 132.2°C, the melt flow rate was 71 gPP / 10 min, the ethylene content was 3.25 mol%, the haze was 10.3%, the tensile yield stress was 33 MPa, the flexural modulus was 1629 MPa, and the impact strength was 2.5 KJ / m 2 。

[0098] Example 11

[0099] 10 g of anhydrous MgCl2 was poured into a three-necked flask that had been fully purged with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The temperature was raised to 130°C while stirring, and the reaction was carried out at this temperature for 3 hours. 3.0 g of tetrabutyl titanate was added, and the reaction was continued at 130°C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and uniform alcoholate solution.

[0100] The prepared uniform solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20°C that had been fully purged with nitrogen over 1 hour. After the addition was complete, the temperature was raised to 80°C over 3 hours. Then, 20 g of diethyl 2-(1-acetyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was added, and the temperature was further raised for 30 min until it reached 110°C. The reaction was carried out at this temperature for 2 hours. After the reaction ended and the liquid was filtered, 200 ml of titanium tetrachloride was added again, and the reaction was carried out at 110°C for 2 hours. After the reaction ended, the reaction solution was filtered out, and it was hot washed 6 times with hexane dried by molecular sieve. The remaining solid product was dried under vacuum to obtain a solid catalyst. Its titanium content was 3.3 wt%, and the content of diethyl 2-(1-acetyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was 4.0 wt%.

[0101] A 5 L high-pressure reactor was heated and evacuated to remove air and water, then purged with nitrogen three times. Then, 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (with diethyl 2-(1-acetyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate as the internal electron donor) was added. The amount of triethylaluminum added was Al / Ti (molar ratio) = 200. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in molar ratio to Ti. Then, 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reactor was closed, the temperature of the reactor was raised to 40°C, and polymerization began. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 10.6 KgPol / g catalyst. The melting point of the ethylene-propylene copolymer was 137.2°C, the melt flow rate was 61.3 gPP / 10 min, the ethylene content was 2.48 mol%, the haze was 14%, the tensile yield stress was 38 MPa, the flexural modulus was 1729 MPa, and the impact strength was 3.3 KJ / m 2 。

[0102] Example 12

[0103] 10 g of anhydrous MgCl2 was poured into a three-necked flask that had been fully purged with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The mixture was stirred and heated to 130°C, and the reaction was carried out at this temperature for 3 hours. Then, 3.0 g of tetrabutyl titanate was added, and the reaction was continued at 130°C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and uniform alcoholate solution.

[0104] The prepared homogeneous solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20 °C that had been fully purged with nitrogen over 1 hour. After the addition was complete, the temperature was raised to 80 °C over 3 hours. Then, 10 g of dimethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was added, and the temperature was further raised for 30 min until it reached 110 °C. The reaction was carried out at this temperature for 2 hours. After the reaction ended and the liquid was filtered, 200 ml of titanium tetrachloride was added again, and the reaction was carried out at 110 °C for 2 hours. After the reaction ended, the reaction solution was filtered out, hot washed 6 times with hexane dried by molecular sieve, and the remaining solid product was dried under vacuum to obtain a solid catalyst. Its titanium content was 3.6 wt%, and the content of dimethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was 6.8 wt%.

[0105] A 5 L high-pressure reactor was heated and evacuated to remove air and water, then purged with nitrogen three times. Then, 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (the internal electron donor was dimethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate) was added. The amount of triethylaluminum added was Al / Ti (molar ratio) = 500. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in molar ratio to Ti. Then, 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reactor was closed, the temperature of the reactor was raised to 40 °C, and polymerization began. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 17.0 KgPol / g catalyst. The melting point of the ethylene-propylene copolymer was 138.2 °C, the melt flow rate was 59.5 gPP / 10 min, the ethylene content was 2.43 mol%, the haze was 15.8%, the tensile yield stress was 39 MPa, the flexural modulus was 1851 MPa, and the impact strength was 3.2 KJ / m 2 。

[0106] Example 13

[0107] 10 g of anhydrous MgCl2 was poured into a three-necked flask that had been fully purged with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The mixture was heated to 130 °C with stirring and reacted at this temperature for 3 hours. Then, 3.0 g of tetrabutyl titanate was added, and the reaction was continued at 130 °C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and homogeneous alcoholate solution.

[0108] The above-prepared homogeneous solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20 °C that had been fully purged with nitrogen over 1 hour. After the addition was complete, the temperature was raised to 80 °C over 3 hours. Then, 20 g of diisopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was added, and the temperature was further raised for 30 min until it reached 110 °C. The reaction was carried out at this temperature for 2 hours. After the reaction ended and the liquid was filtered, 200 ml of titanium tetrachloride was added again, and the reaction was carried out at 110 °C for 2 hours. After the reaction ended, the reaction solution was filtered out, and the remaining solid product was washed 6 times with hexane dried over molecular sieves and then dried under vacuum to obtain a solid catalyst. Its titanium content was 7.8 wt%, and the content of diisopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was 10.0 wt%.

[0109] A 5 L high-pressure reactor was heated and evacuated to remove air and water, then purged with nitrogen three times. Then, 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (with 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate as the internal electron donor) was added. The amount of triethylaluminum added was Al / Ti (molar ratio) = 500. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in molar ratio to Ti. Then, 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reactor was closed, the temperature of the reactor was raised to 40 °C, and polymerization began. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 17.5 KgPol / g catalyst. The melting point of the ethylene-propylene copolymer was 138.2 °C, the melt flow rate was 59.9 gPP / 10 min, the ethylene content was 2.26 mol%, the haze was 16%, the tensile yield stress was 38 MPa, the flexural modulus was 1833 MPa, and the impact strength was 2.9 KJ / m 2 。

[0110] Example 14

[0111] 10 g of anhydrous MgCl2 was poured into a three-necked flask that had been fully purged with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The mixture was stirred and heated to 130 °C and reacted at this temperature for 3 hours. Then, 3.0 g of tetrabutyl titanate was added, and the reaction was continued at 130 °C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and homogeneous alcoholate solution.

[0112] The above-prepared homogeneous solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20°C that had been fully purged with nitrogen over 1 hour. After the addition was complete, the temperature was raised to 80°C over 3 hours. Then, 10 g of isopropyl tert-butyl (2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate was added, and the temperature was further raised for 30 min until it reached 110°C. The reaction was carried out at this temperature for 2 hours. After the reaction ended and the liquid was filtered, 200 ml of titanium tetrachloride was added again, and the reaction was carried out at 110°C for 2 hours. After the reaction ended, the reaction solution was filtered out, and the remaining solid product was washed 6 times with hot hexane dried by molecular sieve, and then the solid catalyst was obtained by vacuum drying. Its titanium content was 2.6 wt%, and the content of isopropyl tert-butyl (2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate was 4.8 wt%.

[0113] A 5 L high-pressure reactor was heated and evacuated to remove air and water, then purged with nitrogen three times. Then, 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (the internal electron donor was isopropyl tert-butyl (2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate) was added. The amount of triethylaluminum added was Al / Ti (molar ratio) = 300. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in molar ratio to Ti. Then, 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reactor was closed, the temperature of the reactor was raised to 40°C, and polymerization was started. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 12.0 KgPol / g catalyst. The melting point of the ethylene-propylene copolymer was 139.4°C, the melt flow rate was 64.3 gPP / 10 min, the ethylene content was 2.75 mol%, the haze was 11.3%, the tensile yield stress was 43 MPa, the flexural modulus was 1665 MPa, and the impact strength was 2.5 KJ / m 2 。

[0114] Example 15

[0115] 10 g of anhydrous MgCl2 was poured into a three-necked flask that had been fully purged with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The mixture was stirred and heated to 130°C, and the reaction was carried out at this temperature for 3 hours. Then, 3.0 g of tetrabutyl titanate was added, and the reaction was continued at 130°C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and homogeneous alcoholate solution.

[0116] The prepared homogeneous solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20 °C that had been fully purged with nitrogen over 1 hour. After the addition was complete, the temperature was raised to 80 °C over 3 hours. Then, 10 g of di-tert-butyl 2-(1,4-dimethyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was added, and the temperature was further raised for 30 min until it reached 110 °C. The reaction was carried out at this temperature for 2 hours. After the reaction ended and the liquid was filtered, 200 ml of titanium tetrachloride was added again, and the reaction was carried out at 110 °C for 2 hours. After the reaction ended, the reaction solution was filtered out, hot washed 6 times with hexane dried by molecular sieve, and the remaining solid product was dried under vacuum to obtain a solid catalyst. Its titanium content was 3.8 wt%, and the content of di-tert-butyl 2-(1,4-dimethyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was 7.1 wt%.

[0117] A 5 L high-pressure reactor was heated and evacuated to remove air and water, then purged with nitrogen three times. Then, 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (the internal electron donor was di-tert-butyl 2-(1,4-dimethyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate) was added. The amount of triethylaluminum added was Al / Ti (molar ratio) = 400. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in molar ratio to Ti. Then, 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reactor was closed, the temperature of the reactor was raised to 40 °C, and polymerization began. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 17.0 KgPol / g catalyst. The melting point of the ethylene-propylene copolymer was 133.2 °C, the melt flow rate was 65.3 gPP / 10 min, the ethylene content was 2.93 mol%, the haze was 10.1%, the tensile yield stress was 32 MPa, the flexural modulus was 1523 MPa, and the impact strength was 3.1 KJ / m 2 。

[0118] Example 16

[0119] 10 g of anhydrous MgCl2 was poured into a three-necked flask that had been fully purged with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The mixture was stirred and heated to 130 °C, and the reaction was carried out at this temperature for 3 hours. Then, 3.0 g of tetrabutyl titanate was added, and the reaction was continued at 130 °C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and homogeneous alcoholate solution.

[0120] The above-prepared homogeneous solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20°C and fully replaced with nitrogen within 1 hour. After the addition was completed, the temperature was raised to 80°C over 3 hours. Then, 20 g of di-tert-butyl 2-(4,5-dichloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was added, and the temperature was further raised for 30 min until it reached 110°C. The reaction was carried out at this temperature for 2 hours. After the reaction ended and the liquid was filtered, 200 ml of titanium tetrachloride was added again, and the reaction was carried out at 110°C for 2 hours. After the reaction ended, the reaction solution was filtered out, and it was washed with hot hexane dried by molecular sieve 6 times. The remaining solid product was dried under vacuum to obtain a solid catalyst. Its titanium content was 4.2 wt%, and the content of di-tert-butyl 2-(4,5-dichloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was 7.7 wt%.

[0121] A 5 L high-pressure reactor was heated and evacuated to remove air and water, and then replaced with nitrogen three times repeatedly. Then, 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (the internal electron donor was di-tert-butyl 2-(4,5-dichloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate) was added. The amount of triethylaluminum added was Al / Ti (mole) = 500. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in terms of the molar ratio to Ti. Then, 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reaction kettle was closed, the temperature of the kettle was raised to 40°C, and polymerization began. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 13.8 KgPol / g catalyst. The melting point of the ethylene-propylene copolymer was 139.1°C, the melt flow rate was 58.7 gPP / 10 min, the ethylene content was 2.07 mol%, the haze was 17.1%, the tensile yield stress was 37 MPa, the flexural modulus was 1787 MPa, and the impact strength was 2.8 KJ / m 2 。

[0122] Example 17

[0123] 10 g of anhydrous MgCl2 was poured into a three-necked flask fully replaced with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The temperature was raised to 130°C while stirring, and the reaction was carried out at this temperature for 3 hours. Then, 3.0 g of tetrabutyl titanate was added, and the reaction was continued at 130°C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and homogeneous alcoholate solution.

[0124] The above-prepared uniform solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20 °C that had been fully purged with nitrogen over 1 hour. After the addition was complete, the temperature was raised to 80 °C over 3 hours. Then, 15 g of di-tert-butyl 2-(4-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was added, and the temperature was further raised for 30 min until it reached 110 °C. The reaction was carried out at this temperature for 2 hours. After the reaction ended, the liquid was filtered, and 200 ml of titanium tetrachloride was added again. The reaction was carried out at 110 °C for 2 hours. After the reaction ended, the reaction solution was filtered out and washed 6 times with hot hexane dried over molecular sieves. The remaining solid product was dried under vacuum to obtain a solid catalyst. Its titanium content was 7.6 wt%, and the content of di-tert-butyl 2-(4-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was 13.8 wt%.

[0125] A 5 L high-pressure reactor was heated and evacuated to remove air and water, then purged with nitrogen three times. Then, 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (with 2-(4-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate as the internal electron donor) was added. The amount of triethylaluminum added was Al / Ti (molar ratio) = 500. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in terms of the molar ratio to Ti. Then, 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reactor was closed, the temperature of the reactor was raised to 40 °C, and polymerization was started. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 18.0 KgPol / g catalyst. The melting point of the ethylene-propylene copolymer was 136.2 °C, the melt flow rate was 66.2 gPP / 10 min, the ethylene content was 2.88 mol%, the haze was 11.7%, the tensile yield stress was 34 MPa, the flexural modulus was 1934 MPa, and the impact strength was 2.4 KJ / m 2 。

[0126] Example 18

[0127] 10 g of anhydrous MgCl2 was poured into a three-necked flask that had been fully purged with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The temperature was raised to 130 °C with stirring and the reaction was carried out at this temperature for 3 hours. Then, 3.0 g of tetrabutyl titanate was added and the reaction was continued at 130 °C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and uniform alcoholate solution.

[0128] The above-prepared homogeneous solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20°C that had been fully purged with nitrogen over 1 hour. After the addition was complete, the temperature was raised to 80°C over 3 hours. Then, 10 g of di-tert-butyl 2-(5-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate was added, and the temperature was further raised for 30 min until it reached 110°C. The reaction was carried out at this temperature for 2 hours. After the reaction ended and the liquid was filtered, 200 ml of titanium tetrachloride was added again, and the reaction was carried out at 110°C for 2 hours. After the reaction ended, the reaction solution was filtered out, hot-washed 6 times with hexane dried over molecular sieves, and the remaining solid product was dried under vacuum to obtain a solid catalyst. Its titanium content was 3.2 wt%, and the content of di-tert-butyl 2-(5-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate was 5.1 wt%.

[0129] A 5 L high-pressure reactor was heated and evacuated to remove air and water, then purged with nitrogen three times repeatedly. Then, 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (with di-tert-butyl 2-(5-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate as the internal electron donor) was added. The amount of triethylaluminum added was Al / Ti (molar ratio) = 200. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in terms of the molar ratio to Ti. Then, 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reactor was closed, the temperature of the reactor was raised to 40°C, and polymerization began. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 13.2 KgPol / g catalyst. The melting point of the ethylene-propylene copolymer was 138.6°C, the melt flow rate was 59.3 gPP / 10 min, the ethylene content was 2.63 mol%, the haze was 15.6%, the tensile yield stress was 34 MPa, the flexural modulus was 1663 MPa, and the impact strength was 3.6 KJ / m 2 。

[0130] Example 19

[0131] 10 g of anhydrous MgCl2 was poured into a three-necked flask that had been fully purged with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The mixture was stirred and heated to 130°C, and the reaction was carried out at this temperature for 3 hours. Then, 3.0 g of tetrabutyl titanate was added, and the reaction was continued at 130°C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and homogeneous alcoholate solution.

[0132] The above-prepared homogeneous solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20 °C that had been fully purged with nitrogen over 1 hour. After the addition was complete, the temperature was raised to 80 °C over 3 hours. Then, 10 g of di-tert-butyl 2-(5-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate was added, and the temperature was further raised for 30 min until it reached 110 °C. The reaction was carried out at this temperature for 2 hours. After the reaction ended and the liquid was filtered, 200 ml of titanium tetrachloride was added again, and the reaction was carried out at 110 °C for 2 hours. After the reaction ended, the reaction solution was filtered out, and the remaining solid product was washed 6 times with hot hexane dried by molecular sieve and then vacuum dried to obtain a solid catalyst. Its titanium content was 3.2 wt%, and the content of di-tert-butyl 2-(5-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate was 6.3 wt%.

[0133] A 5 L high-pressure reactor was heated and evacuated to remove air and water, then purged with nitrogen three times. Then, 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (the internal electron donor was di-tert-butyl 2-(5-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate) was added. The amount of triethylaluminum added was Al / Ti (molar ratio) = 400. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in molar ratio to Ti. Then, 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reactor was closed, the temperature of the reactor was raised to 40 °C, and polymerization began. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 17.0 KgPol / g catalyst. The melting point of the ethylene-propylene copolymer was 135.2 °C, the melt flow rate was 58.7 gPP / 10 min, the ethylene content was 2.43 mol%, the haze was 16.9%, the tensile yield stress was 36 MPa, the flexural modulus was 1799 MPa, and the impact strength was 4.2 KJ / m 2 。

[0134] Example 20

[0135] 10 g of anhydrous MgCl2 was poured into a three-necked flask that had been fully purged with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The mixture was stirred and heated to 130 °C and reacted at this temperature for 3 hours. Then, 3.0 g of tetrabutyl titanate was added, and the reaction was continued at 130 °C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and homogeneous alcoholate solution.

[0136] The above-prepared uniform solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20°C that had been fully replaced with nitrogen within 1 hour. After the addition was complete, the temperature was raised to 80°C over 3 hours. 17 g of di-tert-butyl 2-(5-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was added, and the temperature was further raised for 30 min until it reached 110°C, and the reaction was carried out at this temperature for 2 hours. After the reaction ended and the liquid was filtered, 200 ml of titanium tetrachloride was added again, and the reaction was carried out at 110°C for 2 hours. After the reaction ended, the reaction solution was filtered out, and it was hot-washed 6 times with hexane dried by molecular sieve. The remaining solid product was dried under vacuum to obtain a solid catalyst. Its titanium content was 8.1 wt%, and the content of di-tert-butyl 2-(5-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was 13.0 wt%.

[0137] A 5 L high-pressure reactor was heated and evacuated to remove air and water, replaced with nitrogen three times repeatedly, and then 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (the internal electron donor was di-tert-butyl 2-(5-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate) was added. The amount of triethylaluminum added was Al / Ti (molar) = 300, the external electron donor C was cyclohexylmethyldimethoxysilane, the amount of the external electron donor added was 20 in terms of the molar ratio to Ti, and then 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reaction kettle was closed, the kettle temperature was raised to 40°C, and polymerization was started. After the reaction for 2 h, the unreacted olefin monomers were discharged. The catalytic activity was 15.4 KgPol / g catalyst, the melting point of the ethylene-propylene copolymer was 136.3°C, the melt flow rate was 59.3 gPP / 10 min, the ethylene content was 2.83 mol%, the haze was 14%, the tensile yield stress was 39 MPa, the flexural modulus was 1744 MPa, and the impact strength was 4.3 KJ / m 2 。

[0138] Example 21

[0139] 10 g of anhydrous MgCl2 was poured into a three-necked flask that had been fully replaced with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The temperature was raised to 130°C while stirring and the reaction was carried out at this temperature for 3 hours. 3.0 g of tetrabutyl titanate was added, and the reaction was continued at 130°C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and uniform alcoholate solution.

[0140] The above-prepared homogeneous solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20 °C that had been fully purged with nitrogen over 1 hour. After the addition was complete, the temperature was raised to 80 °C over 3 hours. Then, 12 g of di-tert-butyl 2-(5-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was added, and the temperature was further raised for 30 min until it reached 110 °C. The reaction was carried out at this temperature for 2 hours. After the reaction ended and the liquid was filtered, 200 ml of titanium tetrachloride was added again, and the reaction was carried out at 110 °C for 2 hours. After the reaction ended, the reaction solution was filtered out, hot-washed 6 times with hexane dried by molecular sieve, and the remaining solid product was dried under vacuum to obtain a solid catalyst. Its titanium content was 3.9 wt%, and the content of di-tert-butyl 2-(5-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate was 7.3 wt%.

[0141] A 5 L high-pressure reactor was heated and evacuated to remove air and water, then purged with nitrogen three times repeatedly. Then, 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (the internal electron donor was di-tert-butyl 2-(5-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate) was added. The amount of triethylaluminum added was Al / Ti (molar ratio) = 300. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in molar ratio to Ti. Then, 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reaction kettle was closed, the temperature of the kettle was raised to 40 °C, and polymerization was started. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 16.0 KgPol / g catalyst. The melting point of the ethylene-propylene copolymer was 139.2 °C, the melt flow rate was 68.1 gPP / 10 min, the ethylene content was 1.93 mol%, the haze was 19.5%, the tensile yield stress was 41 MPa, the flexural modulus was 1972 MPa, and the impact strength was 1.9 KJ / m 2 。

[0142] Example 22

[0143] 10 g of anhydrous MgCl2 was poured into a three-necked flask that had been fully purged with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The mixture was stirred and heated to 130 °C, and the reaction was carried out at this temperature for 3 hours. Then, 3.0 g of tetrabutyl titanate was added, and the reaction was continued at 130 °C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and homogeneous alcoholate solution.

[0144] The above-prepared homogeneous solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20°C that had been fully purged with nitrogen over 1 hour. After the addition was complete, the temperature was raised to 80°C over 3 hours. 21 g of di-tert-butyl 2-(4,5,6-trichloro-1-benzyl-2-oxy-1,2-dihydroindol-3-yl)malonate was added, and the temperature was further raised for 30 min until it reached 110°C. The reaction was carried out at this temperature for 2 hours. After the reaction ended and the liquid was filtered, 200 ml of titanium tetrachloride was added again, and the reaction was carried out at 110°C for 2 hours. After the reaction ended, the reaction solution was filtered out, hot washed 6 times with hexane dried over molecular sieves, and the remaining solid product was dried under vacuum to obtain a solid catalyst. Its titanium content was 6.4 wt%, and the content of di-tert-butyl 2-(4,5,6-trichloro-1-benzyl-2-oxy-1,2-dihydroindol-3-yl)malonate was 11.9 wt%.

[0145] A 5 L high-pressure reactor was heated and evacuated to remove air and water, purged with nitrogen three times repeatedly, and then 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (the internal electron donor was di-tert-butyl 2-(4,5,6-trichloro-1-benzyl-2-oxy-1,2-dihydroindol-3-yl)malonate) was added. The amount of triethylaluminum added was Al / Ti (molar ratio) = 400. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in molar ratio to Ti. Then 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reactor was closed, the reactor temperature was raised to 40°C, and polymerization began. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 18.0 KgPol / g catalyst. The melting point of the ethylene-propylene copolymer was 137.2°C, the melt flow rate was 60.3 gPP / 10 min, the ethylene content was 2.73 mol%, the haze was 13.6%, the tensile yield stress was 35 MPa, the flexural modulus was 1831 MPa, and the impact strength was 3.2 KJ / m 2 。

[0146] Example 23

[0147] 10 g of anhydrous MgCl2 was poured into a three-necked flask that had been fully purged with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The temperature was raised to 130°C while stirring, and the reaction was carried out at this temperature for 3 hours. 3.0 g of tetrabutyl titanate was added, and the reaction was continued at 130°C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and homogeneous alcoholate solution.

[0148] The above-prepared uniform solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20 °C that had been fully purged with nitrogen over 1 hour. After the addition was complete, the temperature was raised to 80 °C over 3 hours. 11 g of di-tert-butyl 2-(4,6-dichloro-5-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate was added, and the temperature was further raised for 30 min until it reached 110 °C. The reaction was carried out at this temperature for 2 hours. After the reaction ended and the liquid was filtered, 200 ml of titanium tetrachloride was added again, and the reaction was carried out at 110 °C for 2 hours. After the reaction ended, the reaction solution was filtered out, and it was hot-washed 6 times with hexane dried by molecular sieve. The remaining solid product was dried under vacuum to obtain a solid catalyst. Its titanium content was 3.1 wt%, and the content of di-tert-butyl 2-(4,6-dichloro-5-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate was 4.7 wt%.

[0149] A 5 L high-pressure reactor was heated and evacuated to remove air and water, and then purged with nitrogen three times repeatedly. Then, 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (the internal electron donor was di-tert-butyl 2-(4,6-dichloro-5-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate) was added. The amount of triethylaluminum added was Al / Ti (molar ratio) = 500. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in terms of the molar ratio to Ti. Then, 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reactor was closed, the temperature of the reactor was raised to 40 °C, and polymerization began. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 10.2 Kg Pol / g catalyst. The melting point of the ethylene-propylene copolymer was 139.2 °C, the melt flow rate was 55.3 gPP / 10 min, the ethylene content was 1.74 mol%, the haze was 20.1%, the tensile yield stress was 45 MPa, the flexural modulus was 2011 MPa, and the impact strength was 1.8 KJ / m 2 。

[0150] Example 24

[0151] 10 g of anhydrous MgCl2 was poured into a three-necked flask that had been fully purged with nitrogen. 50 ml of decane and 50.0 ml of isooctanol were added. The temperature was raised to 130 °C while stirring, and the reaction was carried out at this temperature for 3 hours. 3.0 g of tetrabutyl titanate was added, and the reaction was continued at 130 °C for 1 hour. After the reaction ended, it was cooled to room temperature to obtain a stable and uniform alcoholate solution.

[0152] The prepared homogeneous solution was added dropwise to a reactor filled with 200 ml of titanium tetrachloride at -20°C and fully replaced with nitrogen within 1 hour. After the addition was completed, the temperature was raised to 80°C over 3 hours, and 17 g of di-tert-butyl 2-(4,6-dichloro-5-bromo-1-benzyl-2-oxy-1,2-dihydroindol-3-yl)malonate was added. The temperature was further raised for 30 min until it reached 110°C, and the reaction was carried out at this temperature for 2 hours. After the reaction ended, the liquid was filtered, 200 ml of titanium tetrachloride was added again, and the reaction was carried out at 110°C for 2 hours. After the reaction ended, the reaction solution was filtered out, and it was hot washed 6 times with hexane dried by molecular sieve. The remaining solid product was dried under vacuum to obtain a solid catalyst. Its titanium content was 8.8 wt%, and the content of di-tert-butyl 2-(4,6-dichloro-5-bromo-1-benzyl-2-oxy-1,2-dihydroindol-3-yl)malonate was 13.6 wt%.

[0153] A 5 L high-pressure reactor was heated and evacuated to remove air and water, replaced with nitrogen three times repeatedly, and then 20 mg of the solid component of the MgCl2-supported TiCl4 catalyst (the internal electron donor was di-tert-butyl 2-(4,6-dichloro-5-bromo-1-benzyl-2-oxy-1,2-dihydroindol-3-yl)malonate) was added. The amount of triethylaluminum added was Al / Ti (molar ratio) = 200. The external electron donor C was cyclohexylmethyldimethoxysilane, and the amount of the external electron donor added was 20 in molar ratio to Ti. Then, 168 mmol of hydrogen, 1.2 kg of propylene, and 120 g of ethylene were added. The reactor was closed, the temperature of the reactor was raised to 40°C, and polymerization started. After 2 h of reaction, the unreacted olefin monomers were discharged. The catalytic activity was 17.3 KgPol / g catalyst, the melting point of the ethylene-propylene copolymer was 139.2°C, the melt flow rate was 67.2 gPP / 10 min, the ethylene content was 2.35 mol%, the haze was 13%, the tensile yield stress was 33 MPa, and the flexural modulus was 1153 MPa, and the impact strength was 4.0 KJ / m 2 。

[0154] Comparative Example 1

[0155] The polymerization process was the same as in Example 7. The catalyst selected was a catalyst with diisobutyl phthalate (DIBP) as the internal electron donor, and the external electron donor was dicyclopentyldimethoxysilane. The catalytic activity was 12.5 KgPol / g catalyst, the melting point of the ethylene-propylene copolymer was 153.5°C, the melt index was 8.6 gPP / 10 min, the ethylene content was 1.13 mol%, and the haze was 63%.

[0156] The catalytic activity of the present invention is higher than that of the comparative example, and the melting point and haze of the ethylene-propylene copolymer are lower, indicating better copolymerization performance. The more ethylene is incorporated and the higher the ethylene content, the lower the melting point and the lower the haze. A high melt index indicates that both the hydrogen regulation performance and copolymerization performance of the catalyst are improved.

[0157] The polyolefin catalytic system for synthesizing ethylene-propylene copolymer of the present invention can improve the hydrogen regulation sensitivity, catalytic activity, and copolymerization performance of propylene and other olefins by introducing an indole oxide structure with high activity and electron cloud enrichment, and obtain an ethylene-propylene random copolymer polypropylene with a more uniform comonomer distribution, better transparency, and processability.

Claims

1. A polyolefin catalytic system for the synthesis of ethylene-propylene copolymer, characterized in that, It contains a solid catalytic component A, an ethylaluminum B and an external electron donor C. Among them, the solid catalytic component A is a solid component of a TiCl4 catalyst supported on MgCl2, and the solid component of the TiCl4 catalyst supported on MgCl2 includes an internal electron donor containing 2-(2-oxo-1,2-dihydroindol-3-yl)ethyl malonate; the ethylaluminum B is triethylaluminum; the external electron donor C is cyclohexylmethyldimethoxysilane.

2. The polyolefin catalytic system for ethylene-propylene copolymer synthesis according to claim 1, wherein The internal electron donor containing 2-(2-oxo-1,2-dihydroindol-3-yl)ethyl malonate is a compound with the structure of formula (I): Among them, R1, R2, R3 and R4 are the same or different; R1 is selected from one or more of halogen, straight-chain or branched C1-C 10 alkyl chains, C1-C 10 alkoxy groups, C6-C 20 aryl groups; R2 and R3 are each independently selected from any one of linear or branched C1-C 10 alkyl; R4 is selected from any one of linear or branched C1-C 10 alkyl, C1-C 10 alkylbenzene, C1-C 10 alkanoyl.

3. The polyolefin catalytic system for the synthesis of ethylene-propylene copolymer according to claim 2, characterized in that, In the solid catalytic component A and the ethylaluminum B, the molar ratio of Al / Ti is 100 - 1000 / 1, and the molar ratio of the external electron donor C to Ti in the solid catalytic component A is 5 - 100 / 1.

4. The polyolefin catalyst system for the synthesis of ethylene-propylene copolymer according to claim 1, characterized in that, The internal electron donor in the solid catalyst component A is selected from: diethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-ethyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-propyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-butyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-isopropyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-tert-butyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-isobutyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-phenyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-acetyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-formyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-cyclopentyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-cyclohexyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, dimethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl ethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl propyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl n-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl isopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, ethyl isopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diisopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl n-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, ethyl tert-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl n-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-phenyl-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-benzyl-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,6-diphenyl-1-methyl-2-oxo-1,Di-tert-butyl 2-(indolin-3-yl)ethylmalonate, di-tert-butyl 2-(1,4-dimethyl-5-phenyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(1,4-dimethyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(1,4-dimethoxy-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4-iodo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(6-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(6-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(6-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(6-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(7-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(7-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(7-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(7-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,5-difluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,5-dichloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,5-dibromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,5,Di-tert-butyl 2-(6-trichloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, dimethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl ethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl propyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl n-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl isopropyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, ethyl isopropyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, diisopropyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, ethyl tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, isopropyl tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(1-benzyl-4-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-iodo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-methoxy-1-benzyl-2-oxo-1,Di-tert-butyl 2-(2,3-dihydro-1H-indol-3-yl)malonate, di-tert-butyl 2-(6-fluoro-1-benzyl-2-oxo-1,2-dihydro-1H-indol-3-yl)malonate, di-tert-butyl 2-(6-chloro-1-benzyl-2-oxo-1,2-dihydro-1H-indol-3-yl)malonate, di-tert-butyl 2-(6-bromo-1-benzyl-2-oxo-1,2-dihydro-1H-indol-3-yl)malonate, di-tert-butyl 2-(6-methoxy-1-benzyl-2-oxo-1,2-dihydro-1H-indol-3-yl)malonate, di-tert-butyl 2-(7-fluoro-1-benzyl-2-oxo-1,2-dihydro-1H-indol-3-yl)malonate, di-tert-butyl 2-(7-chloro-1-benzyl-2-oxo-1,2-dihydro-1H-indol-3-yl)malonate, di-tert-butyl 2-(7-bromo-1-benzyl-2-oxo-1,2-dihydro-1H-indol-3-yl)malonate, di-tert-butyl 2-(7-methoxy-1-benzyl-2-oxo-1,2-dihydro-1H-indol-3-yl)malonate, di-tert-butyl 2-(4,5-difluoro-1-benzyl-2-oxo-1,2-dihydro-1H-indol-3-yl)malonate, di-tert-butyl 2-(4,5-dichloro-1-benzyl-2-oxo-1,2-dihydro-1H-indol-3-yl)malonate, di-tert-butyl 2-(4,5-dibromo-1-benzyl-2-oxo-1,2-dihydro-1H-indol-3-yl)malonate, di-tert-butyl 2-(4,5,6-trichloro-1-benzyl-2-oxo-1,2-dihydro-1H-indol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-methoxy-1-benzyl-2-oxo-1,2-dihydro-1H-indol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-fluoro-1-benzyl-2-oxo-1,2-dihydro-1H-indol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-bromo-1-benzyl-2-oxo-1,2-dihydro-1H-indol-3-yl)malonate, or a mixture of two or more thereof., 5. A method for preparing a polyolefin catalyst system, characterized in that, To prepare the polyolefin catalytic system as claimed in claim 1, it is specifically implemented according to the following steps: Step 1, prepare the solid catalytic component A, that is, prepare the solid component of the TiCl4 catalyst supported on MgCl2; Step 2, mix the prepared solid component of the TiCl4 catalyst supported on MgCl2, the ethylaluminum B and the external electron donor C to form a polyolefin catalytic system, where the ethylaluminum B is triethylaluminum; the external electron donor C is cyclohexylmethyldimethoxysilane.

6. The preparation method of the polyolefin catalyst system according to claim 5, characterized in that, The specific preparation steps of the solid component of the TiCl4 catalyst supported on MgCl2 in Step 1 are as follows: Step 1.1, pour 10 - 50 equiv of anhydrous MgCl2 into a three-necked flask fully replaced with nitrogen, then add 50 - 150 ml of decane and 50 - 150 ml of isooctanol, heat to 130 - 200 °C while stirring, and react at this temperature for 3 hours. Then add 1 equiv of tetrabutyl titanate and continue to react at 130 °C for 1 - 12 hours. After the reaction is completed, cool to room temperature to obtain a stable and uniform alcoholate solution; Step 1.2, dropwise add the alcoholate solution obtained in Step 1.1 for 1 hour, and drop it all into a reactor containing 200 - 500 ml of titanium tetrachloride that has been fully replaced with nitrogen and has a temperature of -20 to -0 °C. After the dropping is completed, heat to 80 - 150 °C over 1 - 24 hours, then add 10 - 50 equiv of the internal electron donor containing 2-(2-oxo-1,2-dihydroindol-3-yl)ethyl malonate, continue to heat for 30 - 50 min until the temperature reaches 100 - 150 °C, and react at this temperature for 1 - 3 hours. After the reaction is completed, filter the liquid, then re-add 100 - 500 ml of titanium tetrachloride at -80 °C and react at 110 °C for 2 hours. After the reaction is completed, filter out the reaction solution; Step 1.3, hot wash the reaction solution obtained in the step with hexane dried by molecular sieve for 5 - 12 times, and the remaining solid product is vacuum dried to obtain the solid component of the TiCl4 catalyst supported on MgCl2, that is, the solid catalytic component A; In the step 2, the molar ratio of Al / Ti in the solid catalytic component A and ethyl aluminum B is 100 - 1000 / 1, and the molar ratio of the external electron donor C to Ti in the solid catalytic component A is 5 - 100 / 1.

7. The preparation method of the polyolefin catalyst system according to claim 6, characterized in that, The internal electron donor containing 2-(2-oxo-1,2-dihydroindol-3-yl)ethyl malonate is a compound with the structure of formula (I): Among them, R1, R2, R3 and R4 are the same or different; R1 is selected from one or more of halogen, linear or branched C1-C 10 alkyl chains, C1-C 10 alkoxy groups, C6-C 20 aryl groups; R2 and R3 are each independently selected from any one of linear or branched C1-C 10 alkyl; R4 is selected from any one of linear or branched C1-C 10 alkyl, C1-C 10 alkylbenzene, C1-C 10 alkanoyl.

8. The preparation method of the polyolefin catalyst system according to claim 6, characterized in that, The internal electron donor in the solid catalyst component A is selected from: diethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-ethyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-propyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-butyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-isopropyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-tert-butyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-isobutyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-phenyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-acetyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-formyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-cyclopentyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diethyl 2-(1-cyclohexyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, dimethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl ethyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl propyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl n-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl isopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, ethyl isopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, diisopropyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl n-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, ethyl tert-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, methyl n-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-phenyl-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(5-benzyl-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethylmalonate, di-tert-butyl 2-(4,6-diphenyl-1-methyl-2-oxo-1,Di-tert-butyl 2-(1,4-dimethyl-5-phenyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(1,4-dimethyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(1,4-dimethoxy-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4-iodo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(5-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(5-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(5-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(5-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(6-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(6-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(6-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(6-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(7-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(7-chloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(7-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(7-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4,5-difluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4,5-dichloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4,5-dibromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)ethyl)malonate, di-tert-butyl 2-(4,5,Di-tert-butyl 2-(6-trichloro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-methoxy-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-fluoro-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-bromo-1-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, dimethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl ethyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl propyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl n-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl isopropyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, ethyl isopropyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, diisopropyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, methyl tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, ethyl tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, isopropyl tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(1-benzyl-4-methyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-iodo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(5-methoxy-1-benzyl-2-oxo-1,Di-tert-butyl 2-(indolin-3-yl)malonate, di-tert-butyl 2-(6-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(6-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(6-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(6-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(7-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(7-chloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(7-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(7-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,5-difluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,5-dichloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,5-dibromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,5,6-trichloro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-methoxy-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-fluoro-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, di-tert-butyl 2-(4,6-dichloro-5-bromo-1-benzyl-2-oxo-1,2-dihydroindol-3-yl)malonate, or a mixture of two or more thereof., 9. The preparation method of the polyolefin catalyst system according to claim 6, characterized in that, The internal electron donor containing 2-(2-oxo-1,2-dihydroindol-3-yl)ethyl malonate in the step 1.2 is specifically prepared according to the following method: Step 1.2.1: In a 100 - 250 mL round-bottom flask, add 1 equiv of isatin compound, dissolve it in 20 - 50 mL of dry ethanol solvent, add 5 - 30 equiv of malonate and 0.2 - 1 equiv of piperidine as a catalyst. Then, install a reflux condenser on the reaction system and heat it to the reflux temperature in an oil bath for about 2 h. After monitoring the reaction to completion by TLC, cool the system to room temperature to precipitate a solid. Then, filter the obtained solid and wash it with 10 - 50 mL of cold ethanol solution in small portions multiple times to obtain an analytical pure compound; Step 1.2.2: Dissolve the analytical pure compound obtained in step 1.2.1 in 10 - 50 mL of DMF solvent, slowly add 1.0 - 10.0 equiv of solid base, and dropwise add 1.0 - 10.0 equiv of liquid bromo protecting group R1. The reaction system reacts overnight at room temperature. After monitoring the reaction to completion by TLC, quench the reaction with water, extract it with 50 - 250 mL of dichloromethane at least 3 times, combine the organic phases, then wash them with saturated brine multiple times, dry them over anhydrous magnesium sulfate, filter off the desiccant, and evaporate the solvent under reduced pressure. The residue is the crude product of the prepared compound; Step 1.2.3: Separate the crude product obtained in step 1.2.2 by silica gel column chromatography. The separation uses petroleum ether:ethyl acetate = 32:1 - 2:1 V / V to obtain the corresponding diester-based oxindole compound, which is an orange-red solid, namely the internal electron donor containing 2-(2-oxo-1,2-dihydroindol-3-yl)ethyl malonate.

10. The method for preparing the polyolefin catalytic system according to claim 6 or 7 further includes carrying out ethylene-propylene copolymerization using the polyolefin catalytic system to obtain an ethylene-propylene copolymer, specifically: Heat and evacuate the high-pressure reaction kettle to remove air and water, displace it with nitrogen at least 3 times repeatedly. Then, add 10 - 50 equiv of the solid component of the MgCl2-supported TiCl4 catalyst, triethyl aluminum, and the external electron donor cyclohexylmethyldimethoxysilane to the high-pressure reaction kettle. Then, add 100 - 500 mmol of hydrogen, 1 - 2 kg of propylene, and 100 - 500 g of ethylene. Close the reaction kettle, raise the kettle temperature to 40 - 45 °C, start the polymerization, and after reacting for 2 - 5 h, discharge the unreacted olefin monomers to obtain an ethylene-propylene copolymer; The molar ratio of Al / Ti in the MgCl₂-supported TiCl₄ catalyst solid and triethylaluminum is 100 - 1000 / 1, and the molar ratio of cyclohexylmethyldimethoxysilane to Ti in the MgCl₂-supported TiCl₄ catalyst solid is 5 - 100 / 1.

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