阅读说明：本技术 一种茂锆型烯烃聚合催化剂及其制备方法和应用 (Zirconocene type olefin polymerization catalyst and preparation method and application thereof ) 是由 姜亦潇 陈洪侠 于 2020-11-23 设计创作，主要内容包括：本发明提出了一种茂锆型烯烃聚合催化剂及其制备方法和应用,属于金属有机化合物合成与高分子材料合成领域。该方法包括以下步骤：向溶剂一中加入芴或芴的衍生物、强碱金属有机化合物一,第一反应,得第一反应液；向上述第一反应液中加入取代富烯,第二反应,得第二反应液；向上述第二反应液中加入强碱金属有机化合物二,第三反应,得第三反应液；向上述第三反应液中加入无水四氯化锆,得茂锆型烯烃聚合催化剂。本发明所制备得到的茂锆型烯烃聚合催化剂主要用于烯烃的均聚和共聚反应。该方法具有合成路线短、反应步骤少、所用溶剂种类少、操作更加简易化、收率高、且产品纯度高的特点,适合于大规模工业化生产。(The invention provides a zirconocene type olefin polymerization catalyst, a preparation method and an application thereof, belonging to the field of metal organic compound synthesis and high polymer material synthesis. The method comprises the following steps: adding fluorene or a fluorene derivative and a strong base metal organic compound I into the solvent I, and carrying out a first reaction to obtain a first reaction solution; adding substituted fulvene into the first reaction solution, and carrying out a second reaction to obtain a second reaction solution; adding a second alkali metal organic compound into the second reaction liquid, and carrying out a third reaction to obtain a third reaction liquid; and adding anhydrous zirconium tetrachloride into the third reaction solution to obtain the zirconocene type olefin polymerization catalyst. The zirconium metallocene type olefin polymerization catalyst prepared by the invention is mainly used for homopolymerization and copolymerization of olefin. The method has the characteristics of short synthetic route, few reaction steps, few types of used solvents, simpler and easier operation, high yield and high product purity, and is suitable for large-scale industrial production.)

1. A method for preparing a zirconocene type olefin polymerization catalyst is characterized by comprising the following steps:

adding fluorene or a fluorene derivative and a strong base metal organic compound I into the solvent I, and carrying out a first reaction to obtain a first reaction solution;

adding substituted fulvene into the first reaction solution, and carrying out a second reaction to obtain a second reaction solution;

adding a second alkali metal organic compound into the second reaction liquid, and carrying out a third reaction to obtain a third reaction liquid;

adding anhydrous zirconium tetrachloride into the third reaction solution, and carrying out a fourth reaction to obtain a zirconocene type olefin polymerization catalyst;

wherein, the zirconocene type olefin polymerization catalyst is shown as the formula (I):

R₁～R₁₄each independently selected from hydrogen or a hydrocarbon group having 1 to 20 carbon atoms; m is a metal of groups IVB, VB and VIB in the periodic table of elements.

2. The production method according to claim 1,

the first solvent is one of diethyl ether, butyl ether, tetrahydrofuran, isoamyl ether and cyclopentyl ether;

preferably, the first solvent is tetrahydrofuran.

3. The production method according to claim 1,

the molar ratio of the fluorene or the fluorene derivative, the strong base metal organic compound I, the substituted fulvene, the strong base metal organic compound II and the anhydrous zirconium tetrachloride is 1 (1-6) to 1-4 (1-6) to 0.5-1.5;

preferably, the molar ratio of the fluorene or the fluorene derivative, the strong base metal organic compound I, the substituted fulvene, the strong base metal organic compound II and the anhydrous zirconium tetrachloride is 1:1:1: 1.

4. The production method according to claim 1,

the strong base metal organic compound I and the strong base metal organic compound II are respectively and independently selected from one of methyllithium, n-butyllithium, n-hexyllithium, sec-butyllithium, phenyllithium, lithium diisopropylamide or lithium hexamethyldisilazide.

5. The production method according to claim 1,

the temperatures of the first reaction, the second reaction, the third reaction and the fourth reaction are respectively 0-25 ℃, 0-25 ℃ and 0-25 ℃; 0-25 ℃;

the time of the first reaction is 1-2 h; the time of the second reaction is 4-8 h; the time of the third reaction is 1-8 h; the time of the fourth reaction is 8-12 h.

6. The production method according to claim 1,

the substituted fulvene is prepared by the following steps:

adding organic ketone compound into solvent II, and reacting with cyclopentadiene or substituted cyclopentadiene under the action of strong alkali to obtain substituted fulvene.

7. The production method according to claim 6,

the second solvent is one of methanol, ethanol and isopropanol.

8. The production method according to claim 6,

the molar ratio of the organic ketone, the strong base and the cyclopentadiene or the substituted cyclopentadiene is 1 (1-2) to 1-5;

preferably, the strong base comprises one or more of potassium hydroxide, sodium acetate, sodium methoxide, sodium ethoxide, sodium carbonate or potassium carbonate.

9. A zirconocene-type olefin polymerization catalyst prepared by the method according to any one of claims 1 to 8.

10. Use of a zirconocene-type olefin polymerization catalyst according to claim 9 in homo-and copolymerization reactions of olefins.

Technical Field

The invention belongs to the field of metal organic compound synthesis and high polymer material synthesis, and particularly relates to a zirconocene type olefin polymerization catalyst, and a preparation method and application thereof.

Background

In recent years, with the development of global economy and the demand for higher performance of synthetic materials, high performance polyolefin materials such as ethylene/α -olefin and ethylene/cycloolefin copolymer are increasingly used, and the demand for the materials is increasing. The production of high performance polyolefin materials by metallocene catalysts is an important development in the field of olefin polymerization.

Exxon Mobi1, Lyondell1 Basel1, Dow chemical, Total, etc. are the leading players of metallocene catalyst development, and some companies have begun to industrially produce metallocene polyethylene (mPE), metallocene polypropylene (mPP), polyolefin elastomer (POE), polyolefin plastomer (POP), etc. High performance metallocene catalysts with novel structures and methods for their synthesis are the focus of research in this field.

A.Razavi, J.L.Atwood et al report the synthesis of diphenylmethylene (cyclopentadiene) (9-fluorenyl) zirconium dichloride (J.organomet. chem.459,117) 1993. The method uses methyl lithium as a reaction reagent and ethyl ether as a reaction solvent, and a solid-phase product is obtained through multi-step reaction.

CN1040036 discloses a metallocene catalyst for producing syndiotactic polyolefin and a preparation method thereof, wherein the metallocene catalyst is prepared by fully contacting cyclopentadiene or substituted cyclized diene and methylene cyclopentadiene to generate bridged dicyclopentadiene or substituted dicyclic diene, and then fully complexing and reacting with a transition metal compound. The synthesis method has long reaction route, multiple synthesis steps and multiple types of used solvents.

CN105646741A discloses a method for synthesizing diphenylmethylene (cyclized diene) (9-fluorenyl) zirconium dichloride, which comprises reacting a fluorene salt with diphenylfulvene, then separating a ligand, and reacting with a metal to obtain a metallocene catalyst. The method still has the defects of more solvent types and dosage, long reaction time, low product yield and the like.

Therefore, in the prior art, the synthesis method of the metallocene catalyst involves multi-step reaction, separation of ligands and the like, so that the yield of the final product is greatly reduced. In addition, the solvent used in the process is various, and excessive solvent complicates solvent treatment (dehydration and deoxidation) and solvent recovery processes, increases production cost, and causes problems that the solvent pollutes the atmosphere along with exhaust emission and the environment is affected by treatment of the waste solvent.

Disclosure of Invention

The invention provides a zirconocene type olefin polymerization catalyst and a preparation method and application thereof, aiming at solving the problems of complex synthesis conditions, long synthesis route, various solvents, long reaction time and high production cost in the existing preparation method of the zirconocene type olefin polymerization catalyst.

The invention provides a preparation method of a zirconocene type olefin polymerization catalyst, which comprises the following steps:

adding fluorene or a fluorene derivative and a strong base metal organic compound I into the solvent I, and carrying out a first reaction to obtain a first reaction solution;

adding substituted fulvene into the first reaction solution, and carrying out a second reaction to obtain a second reaction solution;

adding a second alkali metal organic compound into the second reaction liquid, and carrying out a third reaction to obtain a third reaction liquid;

adding anhydrous zirconium tetrachloride into the third reaction solution, and carrying out a fourth reaction to obtain a zirconocene type olefin polymerization catalyst;

wherein, the zirconocene type olefin polymerization catalyst is shown as the formula (I):

R₁～R₁₄each independently selected from hydrogen or a hydrocarbon group having 1 to 20 carbon atoms; m is a metal of groups IVB, VB and VIB in the periodic table of elements.

Further, the first solvent is one of diethyl ether, butyl ether, tetrahydrofuran, isoamyl ether and cyclopentyl ether;

preferably, the first solvent is tetrahydrofuran.

Furthermore, the molar ratio of the fluorene or the fluorene derivative, the strong base metal organic compound I, the substituted fulvene, the strong base metal organic compound II and the anhydrous zirconium tetrachloride is 1 (1-6) to 1-4 (1-6) to 0.5-1.5.

Further, the first strong base metal organic compound and the second strong base metal organic compound are respectively and independently selected from one of methyllithium, n-butyllithium, n-hexyllithium, sec-butyllithium, phenyllithium, lithium diisopropylamide or lithium hexamethyldisilazide.

Further, the temperatures of the first reaction, the second reaction, the third reaction and the fourth reaction are respectively 0-25 ℃, 0-25 ℃ and 0-25 ℃; 0-25 ℃;

the time of the first reaction is 1-2 h; the time of the second reaction is 4-8 h; the time of the third reaction is 1-8 h; the time of the fourth reaction is 8-12 h.

Further, the substituted fulvene is prepared by the following steps:

adding organic ketone compound into solvent II, and reacting with cyclopentadiene or substituted cyclopentadiene under the action of strong alkali to obtain substituted fulvene.

Further, the second solvent is one of methanol, ethanol and isopropanol.

Further, the molar ratio of the organic ketone, the strong base and the cyclopentadiene or the substituted cyclopentadiene is 1 (1-2) to 1-5;

preferably, the strong base comprises one or more of potassium hydroxide, sodium acetate, sodium methoxide, sodium ethoxide, sodium carbonate or potassium carbonate.

The invention also provides the zirconocene type olefin polymerization catalyst prepared by the preparation method.

The invention also provides the application of the zirconocene type olefin polymerization catalyst in the homopolymerization and copolymerization reaction of olefin.

The invention has the following advantages:

the invention provides a preparation method of a zirconocene type olefin polymerization catalyst, which takes a micromolecule ether compound as a solvent, and leads fluorene or a fluorene derivative to react with a strong alkali metal organic compound to obtain metal fluorene salt; the metal fluorene salt reacts with substituted fulvene, strong alkali metal organic compound is continuously added for reaction under the condition of not separating and not changing solvent, and finally anhydrous zirconium tetrachloride is added for direct one-step synthesis to obtain the zirconocene type olefin polymerization catalyst. The preparation method has the advantages of simple process flow, short reaction time, few types of used solvents, mild reaction conditions, high product yield, high product purity and low cost of the synthesis method, and is beneficial to realizing the industrial production of the catalyst.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a nuclear magnetic hydrogen spectrum of diphenylmethylene (cyclopentadiene) (9-fluorenyl) zirconium dichloride prepared in example 1 of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The embodiments and features of the embodiments of the present invention may be combined with each other without conflict.

When a zirconocene type olefin polymerization catalyst is prepared in the prior art, 1 time of strong alkali metal organic compound such as n-butyl lithium is usually added when substituted fulvene reacts with fluorene and derivatives thereof to synthesize a ligand, and the ligand is obtained through purification steps such as separation, washing and the like after the reaction; the ligand reacts with 2 times of n-butyl lithium for dehydrogenation to obtain a ligand intermediate with 2 Li ions, and then the ligand intermediate reacts with ZrCl₄Reacting, filtering, washing and drying to obtain the target product, namely the zirconocene catalyst. However, the synthesis method by ligand separation is complex, the reaction route is long, and the yield of the final product, namely the zirconocene compound, is greatly reduced by the separation and purification steps.

An embodiment of the invention provides a preparation method of a zirconocene type olefin polymerization catalyst, which comprises the following steps:

1) adding fluorene or a fluorene derivative and a strong base metal organic compound I into the solvent I, and carrying out a first reaction to obtain a first reaction solution;

2) adding substituted fulvene into the first reaction solution, and carrying out a second reaction to obtain a second reaction solution;

3) adding a second alkali metal organic compound into the second reaction liquid, and carrying out a third reaction to obtain a third reaction liquid;

4) adding anhydrous zirconium tetrachloride into the third reaction solution, and carrying out a fourth reaction to obtain a zirconocene type olefin polymerization catalyst;

wherein, the zirconocene type olefin polymerization catalyst is shown as the formula (I):

R₁～R₁₄each independently selected from hydrogen or a hydrocarbon group having 1 to 20 carbon atoms; m is a metal of groups IVB, VB and VIB in the periodic table of elements.

The preparation method of the zirconocene type olefin polymerization catalyst provided by the embodiment of the invention adopts a one-step synthesis method, takes a micromolecule ether compound as a solvent, and reacts fluorene or a fluorene derivative with a strong alkali metal organic compound to obtain metal fluorene salt; the metal fluorene salt reacts with substituted fulvene, strong alkali metal organic compound is continuously added for reaction under the condition of not separating and replacing solvent, and finally anhydrous zirconium tetrachloride is added, so that the zirconocene type olefin polymerization catalyst is directly obtained.

In the preparation method of the zirconocene type olefin polymerization catalyst provided by the embodiment of the invention, the ligand synthesized by the reaction of substituted fulvene and fluorene and derivatives thereof has one lithium cation and one negative charge, and only 1 time of n-butyllithium is needed to obtain a ligand intermediate with 2 lithium cations during the continuous reaction, and then the ligand intermediate is reacted with ZrCl₄And (3) reacting, namely filtering and drying by utilizing the solubility difference between the product and the reactant to obtain the product, namely the zirconocene catalyst.

The preparation method has the advantages of simple process flow, short reaction time, few types of used solvents, mild reaction conditions, high product yield, high product purity and low cost of the synthesis method, and is beneficial to realizing the industrial production of the catalyst.

In an embodiment of the present invention, the first solvent is one of diethyl ether, dibutyl ether, tetrahydrofuran, isoamyl ether and cyclopentyl ether; preferably, the first solvent is tetrahydrofuran.

In one embodiment of the present invention, the molar ratio of the first solvent to the fluorene or the fluorene derivative is 1 (10-15).

In one embodiment of the present invention, the molar ratio of the fluorene or the fluorene derivative, the first strong base metal organic compound, the substituted fulvene, the second strong base metal organic compound, and the anhydrous zirconium tetrachloride is 1 (1-6) to 1 (4) to 1-6 to 0.5-1.5. Preferably, the molar ratio of the fluorene or the fluorene derivative, the strong base metal organic compound I, the substituted fulvene, the strong base metal organic compound II and the anhydrous zirconium tetrachloride is 1:1:1: 1.

In one embodiment of the invention, the structure of the fluorene or the fluorene derivative is shown as a formula (II),

wherein R is₇～R₁₄Each independently selected from hydrogen or a hydrocarbon group having 1 to 20 carbon atoms.

In an embodiment of the present invention, the first alkali metal organic compound and the second alkali metal organic compound are respectively and independently selected from one of methyllithium, n-butyllithium, n-hexyllithium, sec-butyllithium, phenyllithium, lithium diisopropylamide, and lithium hexamethyldisilazide.

In one embodiment of the present invention, the temperatures of the first reaction, the second reaction, the third reaction, and the fourth reaction are 0 ℃ to 25 ℃, and 0 ℃ to 25 ℃, respectively.

In one embodiment of the invention, the time of the first reaction is 1-2 h; the time of the second reaction is 4-8 h; the time of the third reaction is 1-2 h; the time of the fourth reaction is 8-12 h.

In an embodiment of the invention, after the fourth reaction is finished, filtering and drying are carried out to obtain the zirconocene type olefin polymerization catalyst.

In one embodiment of the present invention, the substituted fulvene is prepared by the following steps:

adding organic ketone compound into solvent II, and reacting with cyclopentadiene or substituted cyclopentadiene under the action of strong alkali to obtain substituted fulvene.

The structure of the substituted fulvene compound is shown as a formula (III),

wherein R is₁～R₆Each independently selected from hydrogen or a hydrocarbon group having 1 to 20 carbon atoms.

In an embodiment of the present invention, the second solvent is one of methanol, ethanol, and isopropanol.

In an embodiment of the invention, the molar ratio of the amount of the second solvent to the amount of the organic ketone is 1 (10-15).

In one embodiment of the present invention, the molar ratio of the organic ketone, the strong base, and the cyclopentadiene or the substituted cyclopentadiene is 1 (1-2) to 1-5.

In one embodiment of the invention, the temperature of the fifth reaction is-15 ℃ to 25 ℃, and the time of the fifth reaction is 8h to 12 h.

In an embodiment of the present invention, the strong base includes one or more of potassium hydroxide, sodium acetate, sodium methoxide, sodium ethoxide, sodium carbonate, and potassium carbonate.

An embodiment of the invention also provides the zirconocene type olefin polymerization catalyst prepared by the preparation method.

An embodiment of the present invention further provides an application of the above-mentioned zirconocene type olefin polymerization catalyst in homopolymerization and copolymerization of olefin. The preparation method of the zirconocene type olefin polymerization catalyst provided by the embodiment of the invention provides good technical support for the research and development of the metallocene catalyst, especially the industrialization aspect; the method is beneficial to developing novel olefin polymer materials with special functions, such as high-performance polyolefin materials of metallocene polyethylene, metallocene polypropylene, metallocene ethylene/linear alpha-olefin copolymer, metallocene ethylene/cycloolefin copolymer, metallocene ethylene/styrene, metallocene polystyrene and the like.

The present invention will be described in detail with reference to examples.

Example 1Preparation method of diphenylmethylene (cyclopentadiene) (9-fluorenyl) zirconium dichloride

Step (1): synthesis of diphenyl fulvene

In a 500mL round bottom flask, about 200mL dicyclopentadiene was added, heated to 180 ℃ in an oil bath for distillation, and the distilled cyclopentadiene was stored at-78 ℃.

Benzophenone (125.00g,686.0mmol), sodium methoxide (41.00g,759.0mmol), and ethanol (500mL) were added to a 1L round bottom flask. Cyclopentadiene (100.0mL,1213mmol) was added slowly and the mixture stirred to give a red solution. After stirring the reaction for 12h, the mixture was filtered to give an orange precipitate, which was washed with 50mL of ethanol. And heating and drying for 8 hours in vacuum to obtain the product, namely orange powder: 136.18g (86.2%).

¹H NMR(300MHz,CDCl₃)δ:7.82(d,1H),7.57(d,1H),7.41(t,1H),7.33(td,1H),3.93(s,1H)。

Step (2): synthesis of diphenylmethylene (cyclopentadiene) (9-fluorenyl) zirconium dichloride

Fluorene (83g,500mmol) was added to a 2L round bottom flask under nitrogen, 500mL of THF was added, and a 2.4M n-butyllithium solution in hexane (208mL,500mmol) was added dropwise at 0 ℃ to give a deep red solution. Slowly heating to room temperature, stirring for reacting for 2h, cooling the reaction liquid to 0 ℃, dissolving 6, 6-diphenyl fullerene (115g, 500mmol) in 500mL THF, slowly dropping the solution into the reaction liquid, stirring for 8h at room temperature, and directly using the obtained solution for next synthesis;

cooling the reaction solution to 0 ℃ under the protection of nitrogen, dropwise adding 2.4M n-butyllithium hexane solution (208mL,500mmol), stirring at room temperature for 8h, and directly using the obtained solution for the next synthesis;

the reaction liquid is cooled to 0 ℃ under the protection of nitrogen, and the anhydrous ZrCl is rapidly cooled₄(116.5g,500mmol) was added to the reaction mixture, which was slowly warmed to room temperature and stirred for 12 h. The precipitated red solid was collected by filtration and dried in vacuo to give 230g of solid in 72.9% yield. The Zr content by ICP analysis was 11%.¹H NMR(400MHz,C₆D₆)δ:7.94(d,2H),7.57(d,2H),7.52(d,2H),7.32(m,2H),7.07(td,2H),7.01(td,2H),6.93(t,2H),6.76(m,2H),6.40(m,2H),6.14(m,4H),5.50(t,2H)。

FIG. 1 is a nuclear magnetic hydrogen spectrum of diphenylmethylene (cyclopentadiene) (9-fluorenyl) zirconium dichloride prepared in example 1 of the present invention.

Test example 1Polymerization experiment of zirconocene type olefin polymerization catalyst

A catalyst system consisting of diphenylmethylene (cyclopentadiene) (9-fluorenyl) zirconium dichloride obtained in example 1, triisobutylaluminum and trityl tetrakis (pentafluorophenyl) borate is used for catalyzing copolymerization of ethylene and 1-octene.

The copolymerization of ethylene/1-octene is carried out in a 300mL stainless steel reaction kettle with a stirrer and adopts a full-automatic temperature control electric heating jacket heating mode. Before copolymerization, the reaction kettle is heated to 120 ℃ and vacuumized for 2h, and then replaced by high-purity nitrogen for 3 times and polymerization-grade ethylene for 3 times. Starting stirring, sequentially adding a reaction solvent, 1-octene and triisobutyl aluminum, heating to a preset temperature, adding a metallocene complex and a boron cocatalyst, maintaining a certain ethylene pressure to start a polymerization reaction, closing an ethylene feeding valve until the reaction is carried out for a preset time, and quickly cooling a polymerization reaction system to 10 ℃ under the combined action of circulating cooling water and an ice bath. Slowly releasing the pressure, and terminating the reaction of the polymerization reaction liquid by using acidified ethanol. The polymer was collected by filtration, washed with deionized water and dried under vacuum to constant weight.

Polymerization results: reaction temperature: under the conditions of 150 deg.C, reaction pressure 2.0MPa, reaction time 10min, 1-octene concentration 2.0M, total solvent content 50mL, catalyst dosage 1. mu. mol, B/Zr 1.1 and Al/Zr 150, the catalyst activity can reach 2.25X 10⁸g/mol.h; the melt index of the product POE is 5.89g/10 min; the density is 0.869g/cm³。

Example 2Preparation method of cyclohexylmethylene (cyclopentadiene) (9-fluorenyl) zirconium dichloride

Step (1): synthesis of cyclohexyl fulvenes

In a 500mL round bottom flask, about 200mL dicyclopentadiene was added, heated to 180 ℃ in an oil bath for distillation, and the distilled cyclopentadiene was stored at-78 ℃.

Cyclohexanone (67.32g,686.0mmol), sodium methoxide (41.00g,759.0mmol), and ethanol (500mL) were added to a 1L round bottom flask. Cyclopentadiene (100.0mL,1213mmol) was added slowly and the mixture stirred to give a red solution. After stirring the reaction for 12h, the mixture was filtered to give an orange precipitate, which was washed with 50mL of ethanol. And heating and drying for 8 hours in vacuum to obtain the product, namely orange powder: 85.62g (85.3%).¹H NMR(400MHz,CDCl₃)δ:6.53(d,2H),6.10(d,2H),2.09(td,4H),1.51(m,6H)。

Step (2): synthesis of cyclohexylmethylene (cyclopentadiene) (9-fluorenyl) zirconium dichloride

Fluorene (83g,500mmol) was added to a 2L round bottom flask under nitrogen, 500mL of THF was added, and a 2.4M n-butyllithium solution in hexane (208mL,500mmol) was added dropwise at 0 ℃ to give a deep red solution. Slowly heating to room temperature, stirring for reacting for 2h, cooling the reaction liquid to 0 ℃, dissolving cyclohexyl fullerene (50.06g, 500mmol) in 500mL THF, slowly dropping the reaction liquid, stirring at room temperature for 8h, and directly using the obtained solution for next synthesis;

cooling the reaction solution to 0 ℃ under the protection of nitrogen, dropwise adding 2.4M n-butyllithium hexane solution (208mL,500mmol), stirring at room temperature for 8h, and directly using the obtained solution for the next synthesis;

the reaction liquid is cooled to 0 ℃ under the protection of nitrogen, and the anhydrous ZrCl is rapidly cooled₄(116.5g,500mmol) was added to the reaction mixture, which was slowly warmed to room temperature and stirred for 12 h. The precipitated red solid was collected by filtration and dried in vacuo to give 189.37g of a solid in 75.4% yield. The Zr content by ICP analysis was 13.2%.¹H NMR(400MHz,C₆D₆)δ:7.94(d,2H),7.57(d,2H),6.76(m,2H),6.40(m,2H),6.14(m,2H),5.50(t,2H),2.15(d,4H),1.53(m,4H),1.43(td,2H)。

The invention proves that the hexamethylene (cyclopentadiene) (9-fluorenyl) zirconium dichloride is successfully prepared.

Test example 2Polymerization experiment of zirconocene type olefin polymerization catalyst

A catalyst system consisting of the cyclohexylmethylene (cyclopentadiene) (9-fluorenyl) zirconium dichloride obtained in the example 2, triisobutylaluminum and trityl tetrakis (pentafluorophenyl) borate is used for catalyzing the copolymerization of ethylene and norbornene.

The ethylene/norbornene copolymerization is carried out in a 300mL stainless steel reaction kettle with a stirrer by adopting a full-automatic temperature control electric heating jacket heating mode. Before copolymerization, the reaction kettle is heated to 120 ℃ and vacuumized for 2h, and then replaced by high-purity nitrogen for 3 times and polymerization-grade ethylene for 3 times. Starting stirring, sequentially adding a reaction solvent, norbornene and triisobutyl aluminum, heating to a preset temperature, adding a metallocene complex and a boron cocatalyst, maintaining a certain ethylene pressure to start a polymerization reaction, and closing an ethylene feeding valve until the reaction is carried out for a preset time, and quickly cooling a polymerization reaction system to 10 ℃ under the combined action of circulating cooling water and an ice bath. Slowly releasing the pressure, and terminating the reaction of the polymerization reaction liquid by using acidified ethanol. The polymer was collected by filtration, washed with deionized water and dried under vacuum to constant weight.

Polymerization results: reaction temperature: at 150 deg.C,The catalyst activity reached 3.22X 10 under the conditions of reaction pressure 2.0MPa, reaction time 10min, norbornene concentration 2.0M, total solvent amount 50mL, catalyst amount 1. mu. mol, B/Zr 1.1 and Al/Zr 150⁸g/mol.h; the melt index of the product POE is 2.12g/10 min; the density is 0.865g/cm³。

The present invention is not limited to the above preferred embodiments, and any modifications, equivalent substitutions, improvements, etc. within the spirit and principle of the present invention should be included in the protection scope of the present invention.