An ethylene-octene copolymer and a method for preparing the same

Abstract

The application discloses an ethylene-octene copolymer and a preparation method thereof, and the ethylene-octene copolymer is a copolymer of ethylene and 1-octene, wherein the insertion rate of 1-octene is 36.9 mol%-49.5 mol%. The ethylene-octene copolymer has a high 1-octene insertion rate, and the CGC metallocene catalyst is used to catalyze polymerization of ethylene and 1-octene, so that the ethylene-octene copolymer with a high 1-octene insertion rate, a high molecular weight and a narrow molecular weight distribution can be prepared at a high temperature, and meanwhile, the problem that the ethylene-octene copolymer elastomer is easy to be precipitated and to cause a coking problem in a high-temperature solution polymerization system is solved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of ethylene-octene copolymer, and particularly relates to an ethylene-octene copolymer and a preparation method thereof. BACKGROUND

[0002] Olefin elastomer (POE) is a kind of polyolefin material prepared by copolymerization of ethylene and alpha-olefin or cyclic olefin, which has the characteristics of low density, high elasticity, excellent mechanical properties and rheological properties, and is widely used in automobile parts, cables, wires, daily necessities, seals and hot melt adhesives. The copolymer of ethylene and 1-octene is a kind of olefin elastomer material with excellent performance, and the insertion rate of 1-octene has a great influence on the performance of the copolymer of ethylene and 1-octene. However, the insertion rate of 1-octene in the ethylene-octene copolymer is difficult to improve, and is generally 3-20 mol%.

[0003] At present, the catalysts for catalytic preparation of POE mainly include metallocene catalysts, FI catalysts, etc. Constrained geometry metallocene catalyst (CGC metallocene catalyst) is one of the most mature POE catalysts in industrial production. Most CGC metallocene catalysts mainly consist of metallocene structure, bridging group, nitrogen coordination group and transition metal center, and have a specific cyclic coordination structure. The CGC metallocene catalyst has attracted much attention due to its high temperature resistance, clear structure, single active center, designable catalyst structure, and high polymerization reactivity. However, when the CGC metallocene catalyst is used to prepare POE at high temperature, the problem of easy precipitation of ethylene-octene copolymer elastomer and sticking of the kettle often occurs. SUMMARY

[0004] In view of the above problems in the prior art, the present application provides an ethylene-octene copolymer, which has a high 1-octene insertion rate. The CGC metallocene catalyst is used to catalyze the polymerization of ethylene and 1-octene, so that the ethylene-octene copolymer with high 1-octene insertion rate, high molecular weight and narrow molecular weight distribution can be prepared at high temperature, and the problem of easy precipitation of ethylene-octene copolymer elastomer and sticking of the kettle in the high-temperature solution polymerization system is solved.

[0005] The present application aims to provide an ethylene-octene copolymer, which is a copolymer of ethylene and 1-octene, wherein the insertion rate of 1-octene is 36.9 mol% to 49.5 mol%.

[0006] In some embodiments of the present application, the insertion rate of 1-octene is 46.1 mol% to 49.5 mol%.

[0007] In some embodiments of the present application, the weight average molecular weight of the ethylene-octene copolymer is 3.0 x 10 5g / mol~1.0×10 6 g / mol, and the PDI is 1.5~2.5.

[0008] In some embodiments of the present application, the weight average molecular weight of the ethylene-octene copolymer is 7.8×10 5 g / mol~1.0×10 6 g / mol, and the PDI is 1.5~2.0.

[0009] Another object of the present application is to provide a preparation method of the ethylene-octene copolymer, comprising the following steps:

[0010] Under the action of the CGC metallocene catalyst and the promoter, ethylene and 1-octene are subjected to polymerization reaction to obtain the ethylene-octene copolymer.

[0011] In some embodiments of the present application, the structural formula of the CGC metallocene catalyst is shown in formula (I):

[0012]

[0013] Formula (I);

[0014] wherein, R1, R2 are independently selected from phenyl, cyclohexane group or fluorine-substituted phenyl.

[0015] In some embodiments of the present application, the promoter comprises a cocatalyst and a solvent.

[0016] In some embodiments of the present application, the temperature of the polymerization reaction is 120~200 ℃, and the time is 15~30 minutes.

[0017] In some embodiments of the present application, the pressure of the ethylene is 0.5 MPa~10 MPa.

[0018] In some embodiments of the present application, the cocatalyst is selected from alkyl aluminum and / or organic boron compound.

[0019] In some embodiments of the present application, the molar ratio of the metal Ti in the CGC metallocene catalyst to the aluminum in the cocatalyst is 1: (100~800).

[0020] In some embodiments of the present application, the molar ratio of the metal Ti in the CGC metallocene catalyst to the boron in the cocatalyst is 1: (1~20).

[0021] In some embodiments of the present application, the alkyl aluminum is selected from at least one of methylaluminoxane, triisobutylaluminum, trimethylaluminum, and triethylaluminum.

[0022] In some embodiments of the present application, the organic boron compound is selected from at least one of Ph3CB(C6F5)4, B(C6F5)3, PhNMe2HB(C6F5)4 and Ph3CB[(CF3)2C6H3]4.

[0023] In some embodiments of the present application, the solvent is selected from at least one of pentane, hexane, heptane, octane, toluene, xylene.

[0024] It is another object of the present application to provide a preparation method of the CGC metallocene catalyst, comprising the following steps:

[0025] S1. 9-fluorenyllithium reacting with substituted dichlorosilane R1R2SiCl2 to obtain fluorenyl-substituted dichlorosilane ; wherein R1, R2 are independently selected from phenyl, cyclohexyl or fluorine-substituted phenyl;

[0026] S2. The fluorenyl-substituted dichlorosilane reacts with 9-fluorenyllithium to obtain ligand ;

[0027] S3. The ligand is mixed with n-butyllithium and then reacts with titanium tetrachloride to obtain the CGC metallocene catalyst.

[0028] In some embodiments of the present application, in S1, the molar ratio of 9-fluorenyllithium to substituted dichlorosilane is 1:1.2-2.0.

[0029] In some embodiments of the present application, in S1, the reaction temperature is -60 ℃- -78 ℃ and the reaction time is 3-5 hours.

[0030] In some embodiments of the present application, in S2, the molar ratio of the fluorenyl-substituted dichlorosilane to 9-fluorenyllithium is 1-1.2:1.8.

[0031] In some embodiments of the present application, in S2, the reaction temperature is 0 ℃-25 ℃ and the reaction time is 1-3 hours.

[0032] In some embodiments of the present application, in S3, the molar ratio of the ligand to titanium tetrachloride is 1:1.1-1.5.

[0033] In some embodiments of the present application, in S3, the molar ratio of the ligand to n-butyllithium is 1:2-2.5.

[0034] In some embodiments of the present application, in S3, the mixing reaction temperature is 0 ℃-25 ℃ and the reaction time is 3-5 hours.

[0035] In some embodiments of the present application, in S3, the temperature of the reaction is 0-25 DEG C, and the time is 12-20 hours.

[0036] Compared with the prior art, the present application has the following beneficial effects:

[0037] (1) The CGC metallocene catalyst prepared by the present application is used to catalyze the polymerization of ethylene and 1-octene, and can produce ethylene-octene copolymer with high 1-octene insertion rate, high molecular weight and narrow molecular weight distribution at high temperature, the highest 1-octene insertion rate can reach 49.5 mol%, the highest weight average molecular weight can reach 1.0 x 10 6 g / mol, and the lowest molecular weight distribution can reach 1.5.

[0038] (2) The CGC metallocene catalyst prepared by the present application is used to catalyze the polymerization of ethylene and 1-octene, and has high polymerization activity, the highest polymerization activity can reach 7.12 x 10 9 g(POE) / (mol(Ti)·h).

[0039] (3) The CGC metallocene catalyst prepared by the present application is used to catalyze the polymerization of ethylene and 1-octene, and solves the problem that the ethylene-octene copolymer elastomer is easy to precipitate and stick to the kettle in the high-temperature solution polymerization system. DETAILED DESCRIPTION

[0040] In order to enable the personnel in the technical field to better understand the technical solutions in the present application, the technical solutions of the present application will be described clearly and completely in combination with the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by the personnel in the field without creative labor should belong to the protection scope of the present application.

[0041] All raw materials of the present application can be obtained through commercial channels.

[0042] The structure of the diphenyl dichlorosilane used in the embodiments of the present application is as follows:

[0043] ;

[0044] The structure of the dicyclohexyl dichlorosilane used in the embodiments of the present application is as follows:

[0045] ;

[0046] The structure of the phenylcyclohexyl dichlorosilane used in the embodiments of the present application is as follows:

[0047] ;

[0048] The structure of the (p-fluorophenyl) cyclohexyl dichlorosilane used in the embodiment of the present application is as follows:

[0049] ;

[0050] The structure of the 9-fluorenyl amine used in the embodiment of the present application is as follows:

[0051] ;

[0052] The synthesis steps of the CGC metallocene catalyst of the present application are as follows:

[0053] .

[0054] Example 1

[0055] The present embodiment provides a fluorenyl-substituted dichlorosilane A1, and the preparation method thereof comprises the following steps:

[0056] Anhydrous and oxygen-free treatment was performed on a 300 mL Schlenk reaction bottle, and the Schlenk reaction bottle was placed in an alcohol bath at -75°C under nitrogen protection. Anhydrous and oxygen-free treated tetrahydrofuran (20 mL) was measured by a syringe and added to the Schlenk reaction bottle, and stirred for 15 min. After the system temperature was stabilized, diphenyl dichlorosilane (36 mmol) was quickly added to the Schlenk reaction bottle by a syringe, and continued to be stirred. After the system temperature was stabilized, 9-fluorenyllithium (24 mmol) dissolved in tetrahydrofuran was slowly added dropwise to the Schlenk reaction bottle, and continued to be stirred for 4 h. After the reaction was completed, tetrahydrofuran was removed by reduced pressure distillation. Anhydrous and oxygen-free treated n-hexane (60 mL) was added, and continued to be stirred and dissolved for 1 h. After standing, the upper layer was separated and filtered to obtain the supernatant. The n-hexane and residual reactants were removed by reduced pressure distillation. The crude product was passed through a silica gel column to obtain the fluorenyl-substituted dichlorosilane A1, and the yield was 54.7 %. The structure of the fluorenyl-substituted dichlorosilane A1 is as follows:

[0057] .

[0058] Example 2

[0059] The present embodiment provides a fluorenyl-substituted dichlorosilane A2, and the preparation method thereof comprises the following steps:

[0060] Anhydrous and anaerobic treatment was performed on a 300 mL Schlenk reaction flask, under the protection of nitrogen, the Schlenk reaction flask was placed in a -78 ℃ alcohol bath, anhydrous and anaerobic treated tetrahydrofuran (20 mL) was added into the Schlenk reaction flask by syringe, stirring for 15 min, after the system temperature stabilized, dicyclohexyldichlorosilane (28.8 mmol) was quickly added into the Schlenk reaction flask by syringe, continue to stir, after the system temperature stabilized, 9-fluorenyllithium (24 mmol) dissolved in tetrahydrofuran was slowly added into the Schlenk reaction flask, continue to stir for 3 h, end the reaction, remove tetrahydrofuran by distillation under reduced pressure, add anhydrous and anaerobic treated n-hexane (60 mL), continue to stir for 1 h, stand, after separation, filter to obtain supernatant, remove n-hexane and residual reactants by distillation under reduced pressure, the crude product was passed through a silica gel column to obtain fluorenyl substituted dichlorosilane A2, yield: 46.3 %; the structure of fluorenyl substituted dichlorosilane A2 is as follows:

[0061] .

[0062] Example 3

[0063] This example provides a fluorenyl substituted dichlorosilane A3, the preparation method thereof comprises the following steps:

[0064] Anhydrous and anaerobic treatment was performed on a 300 mL Schlenk reaction flask, under the protection of nitrogen, the Schlenk reaction flask was placed in a -60 ℃ alcohol bath, anhydrous and anaerobic treated tetrahydrofuran (20 mL) was added into the Schlenk reaction flask by syringe, stirring for 15 min, after the system temperature stabilized, phenylcyclohexyldichlorosilane (48 mmol) was quickly added into the Schlenk reaction flask by syringe, continue to stir, after the system temperature stabilized, 9-fluorenyllithium (24 mmol) dissolved in tetrahydrofuran was slowly added into the Schlenk reaction flask, continue to stir for 2 h, end the reaction, remove tetrahydrofuran by distillation under reduced pressure, add anhydrous and anaerobic treated n-hexane (60 mL), continue to stir for 1 h, stand, after separation, filter to obtain supernatant, remove n-hexane and residual reactants by distillation under reduced pressure, the crude product was passed through a silica gel column to obtain fluorenyl substituted dichlorosilane A3, yield: 57.0 %; the structure of fluorenyl substituted dichlorosilane A3 is as follows:

[0065] .

[0066] Example 3

[0067] This example provides a fluorenyl substituted dichlorosilane A4, the preparation method thereof comprises the following steps:

[0068] A 300 mL Schlenk flask was treated with anhydrous and oxygen-free, and under the protection of nitrogen, the Schlenk flask was placed in an alcohol bath at -68 ℃, and anhydrous and oxygen-free treated tetrahydrofuran (20 mL) was added to the Schlenk flask with a syringe, stirred for 15 min, and after the system temperature stabilized, (p-fluorophenyl) cyclohexyldichlorosilane (40 mmol) was quickly added to the Schlenk flask with a syringe, and continued to stir, and after the system temperature stabilized, 9-fluorenyllithium (24 mmol) dissolved in tetrahydrofuran was slowly added dropwise to the Schlenk flask, and continued to stir for 3.5 h, and the reaction was completed, and tetrahydrofuran was removed by distillation under reduced pressure, anhydrous and oxygen-free treated n-hexane (60 mL) was added, and continued to stir for 1 h, and then stood, and after the layers were separated, filtered, and the supernatant was obtained, and n-hexane and residual reactants were removed by distillation under reduced pressure, and the crude product was passed through a silica gel column to obtain fluorenyl-substituted dichlorosilane A4, yield: 56.9 %; the structure of fluorenyl-substituted dichlorosilane A4 is as follows:

[0069] .

[0070] Example 5

[0071] This example provides a ligand L1, and the preparation method thereof comprises the following steps:

[0072] S1. A 300 mL Schlenk flask was treated with anhydrous and oxygen-free, and under the protection of nitrogen, 9-fluorenylamine (20 mmol) was added to the Schlenk flask with a syringe, and then 50 mL of n-hexane treated with sodium metal reflux for 48 h was added to the Schlenk flask with a syringe, and the Schlenk flask was placed in an ice water bath at 0 ℃, and stirred for 15 min; n-butyllithium solution (2.5 M / L, dissolved in n-hexane) (24 mmol) was added dropwise to the Schlenk flask with a syringe, and continued to stir for 15 min at low temperature, and then the reaction was carried out at room temperature for 4 h, and after the reaction was completed, the solid was filtered and dried to obtain 9-fluorenyllithium;

[0073] S2. Anhydrous and anaerobic treatment was performed on a 300 mL Schlenk reaction flask, fluorenyl-substituted dichlorosilane A1 (20 mmol) was added, nitrogen was replaced for 3 times, 50 mL of tetrahydrofuran was added to the Schlenk reaction flask by using a syringe, and stirring and dissolving were performed for 15 min. 9-Fluorenylamine lithium (30 mmol) was taken to another Schlenk reaction flask, 50 mL of tetrahydrofuran was added, stirring and dissolving were performed, and 9-fluorenylamine lithium dissolved in tetrahydrofuran was obtained. The two Schlenk reaction flasks were respectively placed in a 0 ℃ ice water bath, after the temperature was stabilized, the 9-fluorenylamine lithium dissolved in tetrahydrofuran was slowly added dropwise to the Schlenk reaction flask containing the fluorenyl-substituted dichlorosilane A1, after the dropwise addition was completed, low-temperature stirring was continued for 15 min, and then the reaction was restored to room temperature for 2 h. Tetrahydrofuran was removed by reduced pressure distillation, 60 mL of n-hexane was added to the Schlenk reaction flask, stirring and dissolving were performed for 1 h, and after standing, the supernatant was retained after filtration, and the supernatant was distilled under reduced pressure. The crude product was subjected to silica gel column chromatography, and the ligand L1 was obtained, with a yield of 75.3 %; the structure of the ligand L1 is as shown below:

[0074] .

[0075] Example 6

[0076] The present example provides a ligand L2, and the preparation method thereof comprises the following steps:

[0077] S1. Anhydrous and anaerobic treatment was performed on a 300 mL Schlenk reaction flask, 9-fluorenylamine (20 mmol) was added to the Schlenk reaction flask by using a syringe under the protection of nitrogen, and 50 mL of n-hexane treated with sodium metal for 48 h was added to the Schlenk reaction flask by using a syringe. The Schlenk flask was placed in a 0 ℃ ice water bath, and stirring and dissolving were performed for 15 min. n-Butyllithium solution (2.5 M / L, dissolved in n-hexane) (24 mmol) was added dropwise to the Schlenk reaction flask, low-temperature stirring was continued for 15 min, and then the reaction was restored to room temperature for 4 h. After the reaction was completed, the solid was retained after filtration, and drying was performed, and 9-fluorenylamine lithium was obtained;

[0078] S2. Anhydrous and anaerobic treatment was performed on a 300 mL Schlenk reaction flask, fluorenyl-substituted dichlorosilane A2 (20 mmol) was added, nitrogen was replaced for 3 times, 50 mL of tetrahydrofuran was added to the Schlenk reaction flask by using a syringe, and stirring and dissolving were performed for 15 min. Lithium 9-fluorenylamine (24 mmol) was taken to another Schlenk reaction flask, 50 mL of tetrahydrofuran was added, stirring and dissolving were performed, and lithium 9-fluorenylamine dissolved in tetrahydrofuran was obtained. The two Schlenk reaction flasks were respectively placed in a 0 ℃ ice water bath, after the temperature was stabilized, lithium 9-fluorenylamine dissolved in tetrahydrofuran was slowly added dropwise to the Schlenk reaction flask containing fluorenyl-substituted dichlorosilane A2, after the dropwise addition was completed, low-temperature stirring was continued for 15 min, and then the reaction was restored to room temperature for 2 h. Tetrahydrofuran was removed by reduced pressure distillation, 60 mL of n-hexane was added to the Schlenk reaction flask, stirring and dissolving were performed for 1 h, and after standing, the supernatant was reserved after filtration, the supernatant was distilled under reduced pressure, and the crude product was subjected to silica gel column chromatography to obtain the ligand L2, and the yield was 71.4 %; the structure of the ligand L2 is as shown below:

[0079] .

[0080] Example 7

[0081] The present example provides a ligand L3, and the preparation method thereof comprises the following steps:

[0082] S1. Anhydrous and anaerobic treatment was performed on a 300 mL Schlenk reaction flask, 9-fluorenylamine (20 mmol) was added to the Schlenk reaction flask by using a syringe under nitrogen protection, and then 50 mL of n-hexane treated with sodium metal for 48 h was added to the Schlenk reaction flask by using a syringe. The Schlenk flask was placed in a 0 ℃ ice water bath, and stirring and dissolving were performed for 15 min. n-Butyllithium solution (2.5 M / L, dissolved in n-hexane) (24 mmol) was added dropwise to the Schlenk reaction flask, low-temperature stirring was continued for 15 min, and then the reaction was restored to room temperature for 4 h. After the reaction was completed, the solid was reserved after filtration, and drying was performed to obtain lithium 9-fluorenylamine;

[0083] S2. Anhydrous and anaerobic treatment was performed on a 300 mL Schlenk reaction flask, fluorenyl-substituted dichlorosilane A3 (20 mmol) was added, nitrogen was replaced for 3 times, 50 mL of tetrahydrofuran was added to the Schlenk reaction flask by using a syringe, and stirring and dissolving were performed for 15 min. 9-Fluorenylamine lithium (36 mmol) was taken to another Schlenk reaction flask, 50 mL of tetrahydrofuran was added, stirring and dissolving were performed, and 9-fluorenylamine lithium dissolved in tetrahydrofuran was obtained. The two Schlenk reaction flasks were respectively placed in a 0 ℃ ice water bath, after the temperature was stabilized, the 9-fluorenylamine lithium dissolved in tetrahydrofuran was slowly added dropwise to the Schlenk reaction flask containing the fluorenyl-substituted dichlorosilane A3, after the dropwise addition was completed, low-temperature stirring was continued for 15 min, and then the reaction was restored to room temperature for 2 h. Tetrahydrofuran was removed by reduced pressure distillation, 60 mL of n-hexane was added to the Schlenk reaction flask, stirring and dissolving were performed for 1 h, and after standing, the supernatant was retained after filtration, and the supernatant was distilled under reduced pressure. The crude product was subjected to silica gel column chromatography, and the ligand L3 was obtained, with a yield of 75.8 %; the structure of the ligand L3 is as shown below:

[0084] .

[0085] Example 8

[0086] The present example provides a ligand L4, and the preparation method thereof comprises the following steps:

[0087] S1. Anhydrous and anaerobic treatment was performed on a 300 mL Schlenk reaction flask, 9-fluorenylamine (20 mmol) was added to the Schlenk reaction flask by using a syringe under the protection of nitrogen, and 50 mL of n-hexane treated with sodium metal for 48 h was added to the Schlenk reaction flask by using a syringe. The Schlenk flask was placed in a 0 ℃ ice water bath, and stirring and dissolving were performed for 15 min. n-Butyllithium solution (2.5 M / L, dissolved in n-hexane) (24 mmol) was added dropwise to the Schlenk reaction flask, low-temperature stirring was continued for 15 min, and then the reaction was restored to room temperature for 4 h. After the reaction was completed, the solid was retained after filtration, and drying was performed, and 9-fluorenylamine lithium was obtained;

[0088] S2. Anhydrous and anaerobic treatment was performed on a 300 mL Schlenk reaction flask, fluorenyl-substituted dichlorosilane A4 (20 mmol) was added, nitrogen was replaced for 3 times, 50 mL of tetrahydrofuran was added into the Schlenk reaction flask by syringe, and stirring and dissolving were performed for 15 min. Lithium 9-fluorenylamine (26 mmol) was taken into another Schlenk reaction flask, 50 mL of tetrahydrofuran was added, stirring and dissolving were performed, and lithium 9-fluorenylamine dissolved in tetrahydrofuran was obtained. The two Schlenk reaction flasks were respectively placed in a 0 ℃ ice water bath, after the temperature was stabilized, lithium 9-fluorenylamine dissolved in tetrahydrofuran was slowly added dropwise into the Schlenk reaction flask containing fluorenyl-substituted dichlorosilane A4, after the dropwise addition was completed, low-temperature stirring was continuously performed for 15 min, and then the temperature was restored to room temperature and reaction was performed for 2 h. Tetrahydrofuran was removed by reduced pressure distillation, 60 mL of n-hexane was added into the Schlenk reaction flask, stirring and dissolving were performed for 1 h, and after standing, the supernatant was reserved after layer separation and filtration. The supernatant was distilled under reduced pressure, and the crude product was subjected to silica gel column to obtain the ligand L4, and the yield was 70.5 %. The structure of the ligand L4 is as shown below:

[0089] .

[0090] Example 9

[0091] The present example provides a CGC metallocene catalyst C1, and a preparation method thereof includes the following steps:

[0092] Anhydrous and anaerobic treatment was performed on a 300 mL Schlenk reaction bottle, ligand L1 (20 mmol) was added, nitrogen was replaced for 3 times, 60 mL of anhydrous and anaerobic treated toluene was taken by a syringe and added into the Schlenk reaction bottle, stirring and dissolving, then the Schlenk reaction bottle was placed in an ice water bath at 0 ℃, stirring was continued for 15 min, n-butyllithium solution (2.5 M / L, dissolved in n-hexane) (40 mmol) was added dropwise into the Schlenk reaction bottle, low temperature reaction was continued for 15 min, then the temperature was increased to room temperature and reaction was continued for 4 h. After the reaction was completed, the Schlenk reaction bottle was placed in an ice water bath at 0 ℃ for cooling, stirring was continued, titanium tetrachloride (26 mmol) was added dropwise into the Schlenk reaction bottle, low temperature reaction was continued for 15 min, then the temperature was increased to room temperature and reaction was continued for 16 h. After the reaction was completed, standing, separation and filtration were performed, the solvent was removed, the precipitate was washed with 40 mL of anhydrous n-hexane, the washing was repeated for 3 times to remove unreacted ligand and titanium tetrachloride, then reduced pressure distillation was performed, 100 mL of dichloromethane was added to dissolve the crude product, standing, separation and filtration were performed, the liquid was reserved, then reduced pressure distillation was performed, when the solvent was removed, 40 mL of n-hexane was immediately added, red granular substance was precipitated, then reduced pressure distillation was performed to remove all the solvent, CGC metallocene catalyst C1 was obtained, the yield was 56.3 %, the CGC metallocene catalyst C1 was characterized by nuclear magnetic resonance, and the nuclear magnetic resonance data were as follows: 1 H-NMR (CDCl3, 400MHz), δ (ppm): 8.46 (d, 8H, Ph), 8.13 (d, 8H, Ph), 8.45-7.37 (m, 10H, Ph).

[0093] The structure of the CGC metallocene catalyst C1 is as follows:

[0094] .

[0095] Example 10

[0096] The present example provides a CGC metallocene catalyst C2, and a preparation method thereof includes the following steps:

[0097] A 300 mL Schlenk reaction flask was treated with anhydrous and oxygen-free, ligand L2 (20 mmol) was added, replaced with nitrogen for 3 times, 60 mL of anhydrous and oxygen-free toluene was taken by a syringe and added into the Schlenk reaction flask, stirred and dissolved, then the Schlenk reaction flask was placed in an ice water bath at 0 ℃, and stirring was continued for 15 min, n-butyllithium solution (2.5 M / L, dissolved in n-hexane) (50 mmol) was added dropwise into the Schlenk reaction flask, and the reaction was continued for 15 min at low temperature, and then the temperature was increased to room temperature and the reaction was continued for 5 h. After the reaction was completed, the Schlenk reaction flask was placed in an ice water bath at 0 ℃, and stirring was continued, titanium tetrachloride (22 mmol) was added dropwise into the Schlenk reaction flask, and the reaction was continued for 15 min at low temperature, and then the temperature was increased to room temperature and the reaction was continued for 12 h. After the reaction was completed, the Schlenk reaction flask was placed in an ice water bath at 0 ℃, and stirring was continued, and the solvent was filtered off after standing and layering, and the filtrate was reserved, and the precipitate was washed with 40 mL of anhydrous n-hexane, and the washing was repeated for 3 times to remove unreacted ligand and titanium tetrachloride, and then the solvent was distilled under reduced pressure, and then 100 mL of dichloromethane was added to dissolve the crude product, and the liquid was reserved after standing and layering, and then the liquid was distilled under reduced pressure, and then 40 mL of n-hexane was added immediately after the appropriate amount of solvent was removed, and red granular material was precipitated, and then the solvent was distilled under reduced pressure to remove all the solvent, and CGC metallocene catalyst C2 was obtained, and the yield was 50.7 %, and the CGC metallocene catalyst C2 was characterized by nuclear magnetic resonance, and the nuclear magnetic resonance data were as follows: 1 H-NMR (CDCI3, 400MHz), δ (ppm): 8.43 (d, 8H, Ph), 8.09 (d, 8H, Ph), 1.52-1.18 (m, 22H, CH2).

[0098] The structure of the CGC metallocene catalyst C2 is as follows:

[0099] .

[0100] Example 11

[0101] The present example provides a CGC metallocene catalyst C3, and the preparation method thereof comprises the following steps:

[0102] A 300 mL Schlenk reaction flask was anhydrous and oxygen-free. Ligand L3 (20 mmol) was added, and nitrogen was purged three times. 60 mL of anhydrous and oxygen-free toluene was added to the Schlenk reaction flask using a syringe and stirred until dissolved. The flask was then placed in an ice-water bath at 0 °C and stirred for 15 min. A 2.5 M / L solution of n-butyllithium (dissolved in n-hexane) (46 mmol) was added dropwise to the flask, and the reaction was carried out at low temperature for 15 min. The temperature was then raised to room temperature and reacted for 3 h. After the reaction was complete, the flask was placed in an ice-water bath at 0 °C and cooled with continuous stirring. Titanium tetrachloride (30 mmol) was added dropwise to the flask, and the reaction was carried out at low temperature for 15 min, then raised to room temperature and reacted for 20 h. After the reaction was completed, the mixture was allowed to stand, and after separation, the solvent was filtered off, retaining the filter residue. The precipitate was washed three times with 40 mL of anhydrous n-hexane to remove unreacted ligands and titanium tetrachloride. Then, the mixture was distilled under reduced pressure, and 100 mL of dichloromethane was added to dissolve the crude product. After standing and separation, the mixture was filtered, retaining the liquid. Then, the mixture was distilled under reduced pressure. When a suitable amount of solvent was removed, 40 mL of n-hexane was immediately added, precipitating red particles. The mixture was then distilled under reduced pressure to remove all solvent, yielding CGC metallocene catalyst C3 with a yield of 57.2%. The CGC metallocene catalyst C3 was characterized by nuclear magnetic resonance (NMR), and its NMR data are as follows: 1 H-NMR (CDCl3, 400MHz), δ(ppm): 8.40(d,8H, Ph), 8.11(d, 8H, Ph), 7.31-7.19(m, 5H, Ph), 1.56-1.17(m, 11H, CH2).

[0103] The structure of C3 in the CGC metallocene catalyst is shown below:

[0104] .

[0105] Example 12

[0106] This embodiment provides a CGC metallocene catalyst C4, the preparation method of which includes the following steps:

[0107] A 300 mL Schlenk reaction flask was anhydrous and oxygen-free. Ligand L4 (20 mmol) was added, and nitrogen was purged three times. 60 mL of anhydrous and oxygen-free toluene was added to the Schlenk reaction flask using a syringe and stirred until dissolved. The flask was then placed in an ice-water bath at 0 °C and stirred for 15 min. A 2.5 M / L solution of n-butyllithium (dissolved in n-hexane) (44 mmol) was added dropwise to the flask, and the reaction was carried out at low temperature for 15 min. The temperature was then raised to room temperature and reacted for 3.5 h. After the reaction was complete, the flask was placed in an ice-water bath at 0 °C and cooled with continuous stirring. Titanium tetrachloride (28 mmol) was added dropwise to the flask, and the reaction was carried out at low temperature for 15 min. The reaction was then raised to room temperature and reacted for 18 h. After the reaction was completed, the mixture was allowed to stand, and after separation, the solvent was filtered off, retaining the filter residue. The precipitate was washed three times with 40 mL of anhydrous n-hexane to remove unreacted ligands and titanium tetrachloride. Then, the mixture was distilled under reduced pressure, and 100 mL of dichloromethane was added to dissolve the crude product. After standing and separation, the mixture was filtered, retaining the liquid. Then, the mixture was distilled under reduced pressure. When a suitable amount of solvent was removed, 40 mL of n-hexane was immediately added, precipitating red particles. The mixture was then distilled under reduced pressure to remove all solvent, yielding the CGC metallocene catalyst C4 in 58.6% yield. The CGC metallocene catalyst C4 was characterized by nuclear magnetic resonance (NMR), and its NMR data are as follows: 1 H-NMR (CDCl3, 400MHz), δ(ppm): 8.39(d,8H, Ph), 8.07(d, 8H, Ph), 7.22-7.17(m, 4H, Ar), 1.50-1.14(m, 11H, CH2).

[0108] The structure of C4 in the CGC metallocene catalyst is shown below:

[0109] .

[0110] Example 13

[0111] This embodiment provides an ethylene-octene copolymer, the preparation method of which includes the following steps:

[0112] S1. Evacuate the high-pressure reactor at high temperature for more than 1 hour to remove water and oxygen, and replace nitrogen three times. Add 1 L of anhydrous and oxygen-free toluene and 2 mol of 1-octene to the high-pressure reactor, stir and heat to 170 °C.

[0113] S2. The CGC metallocene catalyst C1 (3 × 10⁻⁶) -3mmol), Ph3CB(C6F5)4(0.03 mmol) in 20 mL of toluene was added into the autoclave, the ethylene pressure was kept at 2 MPa, the reaction was stirred for 20 min, the polymerization was terminated by adding acidified alcohol solution, the ethylene pressure was closed, and the temperature was decreased to below 50°C, then the mixture after reaction was poured into a beaker, whether the ethylene-octene copolymer elastomer was precipitated and stuck in the autoclave was observed, and the mixture was filtered and washed with ethanol, and then dried in a vacuum drying oven at 50°C to obtain the ethylene-octene copolymer.

[0114] Example 14

[0115] The present example provides an ethylene-octene copolymer, and a preparation method thereof includes the following steps:

[0116] S1. The autoclave was vacuumed at high temperature for more than 1 h to remove water and oxygen, and was replaced with nitrogen for 3 times, 1 L of anhydrous and oxygen-free toluene and 1-octene (1 mol) were added into the autoclave, and the mixture was stirred and heated to 200°C;

[0117] S2. CGC metallocene catalyst C1 (2×10 -3 mmol), B(C6F5)3(0.002 mmol) in 20 mL of toluene was added into the autoclave, the ethylene pressure was kept at 10 MPa, the reaction was stirred for 30 min, the polymerization was terminated by adding acidified alcohol solution, the ethylene pressure was closed, and the temperature was decreased to below 50°C, then the mixture after reaction was poured into a beaker, whether the ethylene-octene copolymer elastomer was precipitated and stuck in the autoclave was observed, and the mixture was filtered and washed with ethanol, and then dried in a vacuum drying oven at 50°C to obtain the ethylene-octene copolymer.

[0118] Example 15

[0119] The present example provides an ethylene-octene copolymer, and a preparation method thereof includes the following steps:

[0120] S1. The autoclave was vacuumed at high temperature for more than 1 h to remove water and oxygen, and was replaced with nitrogen for 3 times, 1 L of anhydrous and oxygen-free toluene and 1-octene (3 mol) were added into the autoclave, and the mixture was stirred and heated to 120°C;

[0121] S2. CGC metallocene catalyst C1 (4×10 -3 mmol), methylaluminoxane (1.6 mmol) in 20 mL of toluene was added into the autoclave, the ethylene pressure was kept at 0.5 MPa, the reaction was stirred for 15 min, the polymerization was terminated by adding acidified alcohol solution, the ethylene pressure was closed, and the temperature was decreased to below 50°C, then the mixture after reaction was poured into a beaker, whether the ethylene-octene copolymer elastomer was precipitated and stuck in the autoclave was observed, and the mixture was filtered and washed with ethanol, and then dried in a vacuum drying oven at 50°C to obtain the ethylene-octene copolymer.

[0122] Example 16

[0123] The present example provides an ethylene-octene copolymer, and a preparation method thereof, comprising the following steps:

[0124] S1. Vacuum the autoclave at high temperature for more than 1 h to remove water and oxygen, replace nitrogen 3 times, add 1 L of anhydrous and oxygen-free treated toluene and 2 mol of 1-octene into the autoclave, stir and heat to 170 ℃;

[0125] S2. Add a 20 mL toluene solution of CGC metallocene catalyst C2 (3×10 -3 mmol) and Ph3CB(C6F5)4 (0.03 mmol) into the autoclave, maintain the ethylene pressure at 2 MPa, stir for 20 min, add an acidified alcohol solution to terminate the polymerization, turn off the ethylene pressure, and after cooling to below 50 ℃, pour the reaction mixture into a beaker, observe whether the ethylene-octene copolymer elastomer is precipitated and stuck to the autoclave, filter and clean with ethanol, and dry in a 50 ℃ vacuum drying oven to obtain the ethylene-octene copolymer.

[0126] Example 17

[0127] The present example provides an ethylene-octene copolymer, and a preparation method thereof, comprising the following steps:

[0128] S1. Vacuum the autoclave at high temperature for more than 1 h to remove water and oxygen, replace nitrogen 3 times, add 1 L of anhydrous and oxygen-free treated toluene and 2 mol of 1-octene into the autoclave, stir and heat to 170 ℃;

[0129] S2. Add a 20 mL toluene solution of CGC metallocene catalyst C3 (3×10 -3 mmol) and Ph3CB(C6F5)4 (0.03 mmol) into the autoclave, maintain the ethylene pressure at 2 MPa, stir for 20 min, add an acidified alcohol solution to terminate the polymerization, turn off the ethylene pressure, and after cooling to below 50 ℃, pour the reaction mixture into a beaker, observe whether the ethylene-octene copolymer elastomer is precipitated and stuck to the autoclave, filter and clean with ethanol, and dry in a 50 ℃ vacuum drying oven to obtain the ethylene-octene copolymer.

[0130] Example 18

[0131] The present example provides an ethylene-octene copolymer, and a preparation method thereof, comprising the following steps:

[0132] S1. The high-pressure reaction kettle is vacuumed at high temperature for more than 1 h to remove water and oxygen, and nitrogen is replaced for 3 times, 1 L of anhydrous and oxygen-free toluene and 1-octene (2 mol) are added into the high-pressure reaction kettle, stirring, heating to 170 DEG C;

[0133] S2. The CGC metallocene catalyst C4 (3 x 10 -3 mmol), a 20 mL toluene solution of Ph3CB(C6F5)4 (0.03 mmol) is added into the high-pressure reaction kettle, the ethylene pressure is kept at 2 MPa, the reaction is stirred for 20 minutes, the polymerization is terminated by adding an acidified alcohol solution, the ethylene pressure is turned off, and after the temperature is reduced to below 50 DEG C, the mixture after the reaction is poured into a beaker, whether the ethylene-octene copolymer elastomer is precipitated and stuck in the kettle is observed, filtered and washed with ethanol, and dried in a 50 DEG C vacuum drying oven to obtain the ethylene-octene copolymer.

[0134] The insertion rate of 1-octene in the ethylene-octene copolymer can be obtained by nuclear magnetic resonance hydrogen spectrum analysis; the molecular weight and the molecular weight distribution (polydispersity coefficient) are measured by high-temperature gas chromatography (using 1,2,4-trichlorobenzene as the solvent, and polystyrene calibration). The structural characteristics of the CGC metallocene catalyst catalyzed ethylene-octene copolymer are shown in Table 1.

[0135] Table 1. Structural characteristics of the ethylene-octene copolymer and the polymerization process.

[0136] copolymer polymerization activity (g(POE) / (mol(Ti)·h)) insertion rate of 1-octene (mol%) weight average molecular weight (g / mol) PDI whether the ethylene-octene copolymer is deposited example 13 7.10 x 10 8 ]] 40.7 1.0 x 10 6 ]]> 2.3 not deposited, not stuck example 14 6.84 x 10 8 ]] 39.4 7.8 x 10 5 ]]> 2.1 not deposited, not stuck example 15 7.61 x 10 8 ]]> 40.0 8.5 x 10 5 ]]> 2.4 not deposited, not stuck example 16 5.63 x 10 8 ]]> 49.5 3.5 x 10 5 ]]> 2.2 not deposited, not stuck example 17 3.68 x 10 8 ]]> 46.1 3.0 x 10 5 ]]> 1.5 not deposited, not stuck example 18 7.12 x 10 9 ]] 36.9 3.2 x 10 5 ]]> 2.5 not deposited, not stuck

[0137] As can be seen from Table 1, the CGC metallocene catalyst prepared by Examples 8-12 of the present application is used to catalyze the copolymerization of ethylene and 1-octene to prepare ethylene-octene copolymer, which can prepare the ethylene-octene copolymer with high 1-octene insertion rate, high molecular weight and narrow molecular weight distribution at high temperature, and at the same time solves the problem that the ethylene-octene copolymer elastomer is easily precipitated and stuck in the kettle in the high-temperature solution polymerization system.

[0138] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and not to limit them, although the present application has been described in detail by comparing the above examples, those skilled in the art should understand that the specific embodiments of the present application can be modified or replaced by equivalents after reading the present application, but these modifications or changes are still within the scope of the present application.

Claims

1. A process for the preparation of an ethylene-octene copolymer, characterized in that, The method comprises the following steps: Under the action of a CGC metallocene catalyst and an auxiliary agent, ethylene and 1-octene are subjected to a polymerization reaction to obtain the ethylene-octene copolymer; The CGC metallocene catalyst has a structural formula as shown in formula (I): Formula (I); R1 and R2 are independently selected from a phenyl group, a cyclohexane group or a fluorine-substituted phenyl group; The insertion rate of 1-octene in the ethylene-octene copolymer is 36.9 mol% to 49.5 mol%.

2. The process for preparing an ethylene-octene copolymer according to claim 1, characterized in that, The weight average molecular weight of the ethylene-octene copolymer is 3.0 x 10 5 g / mol ~ 1.0 x 10 6 g / mol, and the PDI is 1.5 ~ 2.

5.

3. The method for producing an ethylene-octene copolymer according to claim 1, characterized by, The preparation method of the CGC metallocene catalyst comprises the following steps: S1. 9-fluorenyllithium with a substituted dichlorosilane R1R2SiCl2 to give a fluorenyl substituted dichlorosilane ; wherein R1, R2are independently selected from phenyl, cyclohexyl or fluorine-substituted phenyl; S2. The fluorenyl-substituted dichlorosilane is reacted with lithium 9-fluorenyl amide to give the ligand ; S3. The ligand is mixed with n-butyllithium and then reacted with titanium tetrachloride to obtain the CGC metallocene catalyst.

4. The process for preparing an ethylene-octene copolymer according to claim 3, characterized in that, The molar ratio of the 9-fluorenyllithium to the substituted dichlorosilane is 1:1.2 to 2.

0.

5. The process for preparing an ethylene-octene copolymer according to claim 3, characterized in that, The molar ratio of the fluorenyl-substituted dichlorosilane to the 9-fluorenyllithium is 1 to 1.2:1.

8.

6. The process for preparing an ethylene-octene copolymer according to claim 3, characterized in that, The molar ratio of the ligand to the titanium tetrachloride is 1:1.1 to 1.

5.

7. The method of producing an ethylene-octene copolymer according to claim 1, characterized by, The auxiliary agent comprises a cocatalyst and a solvent. And / or, the temperature of the polymerization reaction is 120 to 200 ℃, and the time is 15 to 30 minutes. And / or, the pressure of the ethylene is 0.5 MPa to 10 MPa.

8. The process for preparing an ethylene-octene copolymer according to claim 7, characterized in that, The cocatalyst is selected from an alkylaluminum and / or an organic boron compound.

9. The process for preparing an ethylene-octene copolymer according to claim 8, characterized in that, The molar ratio of the metal Ti in the CGC metallocene catalyst to the aluminum in the cocatalyst is 1:(100 to 800).

10. The method of producing an ethylene-octene copolymer according to claim 8, characterized by, The molar ratio of the metal Ti in the CGC metallocene catalyst to the boron in the cocatalyst is 1:(1 to 20).

11. The method of producing an ethylene-octene copolymer according to claim 8, characterized in that, The alkylaluminum is selected from at least one of methylaluminoxane, triisobutylaluminum, trimethylaluminum and triethylaluminum. And / or, the organic boron compound is selected from at least one of Ph3CB(C6F5)4, B(C6F5)3, PhNMe2HB(C6F5)4 and Ph3CB[(CF3)2C6H3]4. And / or, the solvent is selected from at least one of pentane, hexane, heptane, octane, toluene and xylene.

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