Preparation method of metallocene polypropylene catalyst
阅读说明：本技术 茂金属聚丙烯催化剂的制备方法 (Preparation method of metallocene polypropylene catalyst ) 是由 李功韬 严婕 周建勇 朱卫东 裴小静 李晓庆 鲍春伟 徐晓 范大鹏 于 2019-08-23 设计创作，主要内容包括：本发明涉及一种聚丙烯催化剂,具体涉及一种茂金属聚丙烯催化剂的制备方法。包括以下步骤：(1)将助催化剂与茂金属化合物加入到接触容器中,使用超声波处理后,得到催化剂前驱体；(2)在氮气保护条件下将载体材料加入到接触容器中,加入溶剂分散载体材料；(3)将步骤(1)得到的催化剂前驱体溶解于溶剂中,加入到接触容器中与载体材料反应,然后使用溶剂洗涤反应物,升温干燥后得到聚丙烯催化剂。本发明制备的催化剂具有较高的催化烯烃聚合活性,降低了聚合产品的生产成本,聚丙烯等规度得到提高。(The invention relates to a polypropylene catalyst, in particular to a preparation method of a metallocene polypropylene catalyst. The method comprises the following steps: (1) adding a cocatalyst and a metallocene compound into a contact container, and performing ultrasonic treatment to obtain a catalyst precursor; (2) adding a carrier material into a contact container under the protection of nitrogen, and adding a solvent to disperse the carrier material; (3) and (2) dissolving the catalyst precursor obtained in the step (1) in a solvent, adding the solution into a contact container to react with a carrier material, washing reactants by using the solvent, and heating and drying to obtain the polypropylene catalyst. The catalyst prepared by the invention has higher catalytic activity for olefin polymerization, reduces the production cost of polymerization products, and improves the isotacticity of polypropylene.)
1. A preparation method of a metallocene polypropylene catalyst is characterized by comprising the following steps: the method comprises the following steps:
(1) adding a cocatalyst and a metallocene compound into a contact container, and performing ultrasonic treatment to obtain a catalyst precursor;
(2) adding a carrier material into a contact container under the protection of nitrogen, and adding a solvent to disperse the carrier material;
(3) and (2) dissolving the catalyst precursor obtained in the step (1) in a solvent, adding the solution into a contact container to react with a carrier material, washing the reactant by using the solvent, and heating and drying to obtain the product.
2. The method for preparing a metallocene polypropylene catalyst according to claim 1, wherein: the method comprises the following steps:
(1) adding a cocatalyst and a metallocene compound into a contact container, and treating for 0.1-4 h by using ultrasonic waves with the ultrasonic frequency of 20-100 KHz to obtain a catalyst precursor;
(2) adding a carrier material into a contact container under the protection of nitrogen, and adding a solvent to disperse the carrier material;
(3) dissolving the catalyst precursor obtained in the step (1) in a solvent, adding the solvent into a contact container, and reacting the solvent with a carrier at a temperature of between 20 ℃ below zero and 200 DEG CReacting the materials for 0.1-48 h, washing reactants for 3 times by using a solvent, heating and drying the catalyst, and fully drying to obtain a product, wherein N is2And (5) protecting for standby.
3. The method for preparing a metallocene polypropylene catalyst according to claim 1 or 2, wherein: the average particle size of the carrier material is 10-1000 μm, and the surface area is 1-500m2Between/g, the porosity of the pores with a diameter of less than 10 μm ranges from 0.1 to 2mL/g, the average diameter of the pores of the support ranges from 0.01 to 2 μm.
4. The method for preparing a metallocene polypropylene catalyst according to claim 1 or 2, wherein: the carrier material is olefin polymer, inorganic oxide or inorganic chloride.
5. The method for preparing a metallocene polypropylene catalyst according to claim 1 or 2, wherein: the cocatalyst is an aluminoxane, a strong uncharged Lewis acid, an ionic compound with Lewis acid cations or an ionic compound with Bronsted acids as cations.
6. The method for preparing a metallocene polypropylene catalyst according to claim 1 or 2, wherein: the cocatalyst is aluminoxane solution, and the atomic ratio of aluminum atoms in the aluminoxane solution to transition metals of the metallocene compound is 10:1 to 1000: 1.
7. The method for preparing a metallocene polypropylene catalyst according to claim 1 or 2, wherein: the cocatalyst is an open-chain aluminoxane compoundOr cyclic aluminoxane compoundsWherein: r21Is C1-C4Alkyl, and m is an integer of 5 to 30.
8. The method for preparing a metallocene polypropylene catalyst according to claim 1 or 2, wherein: the metallocene compound has the following structure:
wherein M is a transition metal belonging to group III, IV, V, VI of the periodic Table of the elements, or to the lanthanide or osmium series; x is a hydrogen atom, a halogen atom, OR R, OR, OSO2CF3、OCOR、SR、NR2Or PR2R is a linear or branched, cyclic or acyclic C1-C40Alkyl radical, C2-C40Alkenyl radical, C1-C40Alkynyl, C6-C40Aryl radical, C7-C40Alkylaryl or C7-C40An arylalkyl group; l is a divalent C containing a heteroatom belonging to groups 13-17 of the periodic Table of the elements1-C40A hydrocarbyl group or a divalent silylene group comprising up to 5 silicon atoms; r1And R5Is C containing a heteroatom belonging to groups 13-17 of the periodic Table of the elements1-C40A hydrocarbon group; r2、R3And R4Equal to or different from each other, is a hydrogen atom or C optionally containing heteroatoms belonging to groups 13-17 of the periodic Table of the elements1-C40A hydrocarbyl group; r6、R7、R8、R9And R10Equal to or different from each other, is a hydrogen atom or C optionally containing heteroatoms belonging to groups 13-17 of the periodic Table of the elements1-C40A hydrocarbyl group.
9. The method for preparing a metallocene polypropylene catalyst according to claim 1 or 2, wherein: m is titanium, zirconium or hafnium; x is chlorine or Cl-C10An alkyl group; l is Si (CH)3)2、SiPh2、SiPhMe、SiMe(SiMe3)、CH2、(CH2)2Or C (CH)2)2；R1And R5Is straight or branched, saturated or unsaturated C1-C20An alkyl group; r2、R3And R4Is a hydrogen atom or C1-C20An alkyl group; r8Is Cl-C40An alkyl group, wherein the atom in the alpha-position is a secondary or tertiary carbon.
Technical Field
The invention relates to a polypropylene catalyst, in particular to a preparation method of a metallocene polypropylene catalyst.
Background
In industrial production, it is desired to increase the activity of metallocene catalysts to reduce the production cost of olefin polymerization. In general, one or more catalytic components may be supported on a porous support. Usually the metallocene is deposited onto the support in solution. Simultaneously, or separately, an activator, such as Methylaluminoxane (MAO) and/or an alkylaluminum compound and/or an ionizing activator, is also deposited onto the support. The catalyst may be dissolved in one or more liquid monomers or in a solvent containing one or more monomers. The monomers used can be polymerized during impregnation of the support or evaporation of the solvent.
Zhangpu Jade et al (chemical research, 2003, 14 (3): 21-23) provide a metallocene catalyst preparation method, weighing silica gel carrier pretreated at high temperature, adding a metered amount of BF3Treating the silica gel surface with the solution, washing off the residue with toluene, and adding a certain amount of Cp2ZrCl2And (3) carrying out loading, carrying out centrifugal separation after loading is finished, washing a solid part for 3 times by using 20mL of methylbenzene, and removing the solvent from the solid part obtained after centrifugal separation in vacuum at room temperature to obtain the loaded catalyst. When the catalyst is used in catalyzing ethylene polymerization, Methyl Aluminoxane (MAO) is added into the polymerization system to activate the catalyst, Al/Zr>500, polymerization results showed that BF was more than that without use3The catalyst of (3) has higher activity.
CN1307065A provides a preparation method of a supported metallocene catalyst, which comprises treating a carrier with MAO for 2 hours under the action of ultrasonic oscillation.Mixing the treated carrier with Et (Ind) under ultrasonic oscillation2ZrCl2Reacting for 15 minutes at room temperature to obtain the supported metallocene olefin polymerization catalyst. The preparation method of the supported metallocene olefin polymerization catalyst has the advantages of short production period, high activity of the prepared catalyst, good polymer form and no sticking to a kettle. The frequency of vibration used by the ultrasound and its effect on the performance of the catalyst are not specified in this patent.
The industrialization of metallocene catalyst creates conditions for producing polypropylene resin with obviously improved physical and mechanical properties, such as producing isotactic polypropylene with ultrahigh rigidity, syndiotactic polypropylene with high transparency, blend of isotactic polypropylene and syndiotactic polypropylene, polypropylene impact copolymer with ultrahigh performance, and the like. However, metallocene catalysts require the addition of a large amount of MAO to increase polymerization activity, which greatly increases the production cost of polypropylene products and limits their industrial applications. The prior art metallocene catalyst preparation techniques are generally prepared by loading metallocene active sites on a MAO treated support after the support has been treated with the MAO. The invention provides a preparation method of a metallocene catalyst which is different from the prior art, MAO and a metallocene active center are premixed, and the mixture is processed by using an ultrasonic technology under a specified frequency, so that the performance of the finally prepared metallocene catalyst can be effectively improved, excellent polymerization activity and isotacticity are reflected, the production cost of a polymer is reduced, and the product quality is improved.
Disclosure of Invention
The technical problem solved by the invention is as follows: overcomes the defects of the prior art, provides a preparation method of a metallocene polypropylene catalyst, improves the polymerization activity of olefin, and reduces the production cost of polymerization products.
The preparation method of the metallocene polypropylene catalyst comprises the following steps:
(1) adding a cocatalyst and a metallocene compound into a contact container, and performing ultrasonic treatment to obtain a catalyst precursor;
(2) adding a carrier material into a contact container under the protection of nitrogen, and adding a solvent to disperse the carrier material;
(3) and (2) dissolving the catalyst precursor obtained in the step (1) in a solvent, adding the solution into a contact container to react with a carrier material, washing the reactant by using the solvent, and heating and drying to obtain the product.
As a preferred technical solution, the preparation method of the metallocene polypropylene catalyst of the present invention comprises the following steps:
(1) adding a cocatalyst and a metallocene compound into a contact container, and treating for 0.1-4 h by using ultrasonic waves with the ultrasonic frequency of 20-100 KHz to obtain a catalyst precursor;
(2) adding a carrier material into a contact container under the protection of nitrogen, and adding a solvent to disperse the carrier material;
(3) dissolving the catalyst precursor obtained in the step (1) in a solvent, adding the solution into a contact container, reacting the solution with a carrier material at the temperature of-20-200 ℃ for 0.1-48 h, washing the reactant for 3 times by using the solvent, heating and drying the catalyst, fully drying to obtain a product, and adding N to the product2And (5) protecting for standby.
Wherein:
to ensure good homogeneity of the system, the contacting vessel is preferably under agitation.
The support material is any support material, preferably a porous material, such as inorganic oxides, inorganic chlorides and resinous materials such as polyolefins or polymers or any other organic support material. Particularly preferred support materials are olefin polymers and prepolymers, and inorganic oxides, such as silica. In addition, inorganic chlorides, such as magnesium chloride, are also suitable. Generally, the support material is not active in olefin polymerization reactions. Furthermore, they may be partially or fully dehydrated.
The support material is preferably an olefin polymer, an inorganic oxide or an inorganic chloride.
The average particle size of the carrier material is 10-1000 μm, and the surface area is 1-500m2Between/g, the porosity of the pores with a diameter of less than 10 μm ranges from 0.1 to 2mL/g, the average diameter of the pores of the support ranges from 0.01 to 2 μm. If the support material is an inorganic oxide, e.g. silica and alumina, the pores thereofThe porosity is generally of a value of 0.9 to 1.7 mL/g. If the support material is a porous prepolymer, its porosity is preferably at least 0.3 mL/g. Prepolymers with higher values of porosity, for example greater than 0.7mL/g or even 1.5m1/g or higher, may also be advantageously employed.
The inorganic support may be heat treated to remove adsorbed water. This drying treatment is generally carried out at 80-300 deg.C, preferably at 100-200 deg.C. Drying is preferably carried out under reduced pressure and/or in a stream of inert gas, for example nitrogen or helium. The inorganic support may also be combustible, in which case the support is treated at 200-1000 ℃ to adjust the concentration of OH groups on the surface.
The cocatalyst is a cation-forming compound which is capable of reacting with the metallocene compound to convert the metallocene compound into a cationic compound. The cocatalyst is an aluminoxane, a strong uncharged Lewis acid, an ionic compound with a Lewis acid cation or an ionic compound with a Bronsted acid as cation.
The cocatalyst is an alumoxane solution, in particular an alumoxane organic solution, such as an alumoxane toluene solution, the atomic ratio of the aluminium atoms in the alumoxane solution to the transition metal of the metallocene compound being from 10:1 to 1000:1, preferably from 20:1 to 500:1, and particularly preferably from 30:1 to 400: 1.
As alumoxanes, use may be made, for example, of the compounds described in WO 00/31090.
The aluminoxane is preferably an open-chain aluminoxane compound of the formula (1) or (2):
wherein: r21Is C1-C4Alkyl, preferably methyl or ethyl, and m is an integer from 5 to 30, preferably from 10 to 25.
Aluminoxanes can generally be prepared by reacting trialkylaluminum solutions with water. The oligomeric aluminoxane compounds obtained in this way are usually mixtures of linear and cyclic chain molecules of various lengths, so that m is to be regarded as an average value. The aluminoxane compounds can also be present in admixture with other metal alkyls, preferably aluminum alkyls.
In addition, it is also possible to replace the aluminoxane compounds of the formulae (1) or (2) with modified alkylaluminum in which some of the hydrocarbon groups or hydrogen atoms are replaced with alkoxy groups, aryloxy groups, siloxy groups or amide groups.
The metallocene compound has the following structure:
wherein M is a transition metal belonging to group III, IV, V, VI of the periodic Table of the elements, or to the lanthanide or osmium series; preferably M is titanium, zirconium or hafnium.
X is a hydrogen atom, a halogen atom, OR R, OR, OSO2CF3、OCOR、SR、NR2Or PR2Group, wherein R is a linear or branched, cyclic or acyclic C1-C40Alkyl radical, C2-C40Alkenyl (alkenyl), C1-C40Alkynyl, C6-C40Aryl radical, C7-C40Alkylaryl or C7-C40An arylalkyl group; optionally containing heteroatoms belonging to groups 13-17 of the periodic Table of the elements; preferably R is a straight or branched chain C1-C20An alkyl group; OR two X may optionally form a substituted OR unsubstituted butadienyl group OR an OR 'O group, wherein R' is selected from C1-C40Alkylene radical, C6-C40Arylene radical, C7-C40Alkylarylene and C7-C40A divalent radical of an arylalkylene group; preferably X is a hydrogen atom, a halogen atom or an R group; more preferably X is chlorine or Cl-C10An alkyl group; such as methyl or ethyl.
L is a divalent C containing a heteroatom belonging to groups 13-17 of the periodic Table of the elements1-C40A hydrocarbon group or a divalent silylene group (silylidene) containing up to 5 silicon atoms; preferably L is a divalent bridging group selected from C1-C40Alkylene radical, C3-C40Cycloalkylene radical, C6-C40Arylene radical, C7-C40Alkylarylene, or C7-C40Arylalkylene groups optionally containing heteroatoms belonging to groups 13-17 of the periodic Table of the elements, and silylene groups containing up to 5 silicon atoms, e.g. SiMe2，SiPh2(ii) a Preferably L is a group (Z (R')2)nWherein Z is a carbon or silicon atom, n is 1 or 2 and R' is C optionally containing a heteroatom belonging to groups 13-17 of the periodic Table of the elements1-C20A hydrocarbyl group; preferably R' is a linear or branched, cyclic or acyclic C1-C20Alkyl radical, C2-C20Alkenyl radical C2-C20Alkynyl, C6-C20Aryl radical, C7-C20Alkylaryl or C7-C20Arylalkyl optionally containing heteroatoms belonging to groups 13-17 of the periodic Table of the elements; more preferably (Z (R')2)nThe radical being Si (CH)3)2，SiPh2，SiPhMe，SiMe(SiMe3)、CH2，(CH2)2And C (CH)2)2(ii) a Even more preferably ((Z (R')2)nIs Si (CH)3)2。
R1And R5Is C optionally containing a heteroatom belonging to groups 13-17 of the periodic Table of the elements1-C40A hydrocarbon group; preferably R1And R5Is straight-chain or branched, cyclic or acyclic C1-C40Alkyl radical, C2-C40Alkenyl radical, C1-C40Alkynyl, C6-C40Aryl radical, C7-C40Alkylaryl or C7-C40An arylalkyl group; optionally containing heteroatoms belonging to groups 13-17 of the periodic Table of the elements; more preferably, R1And R5Is straight or branched, saturated or unsaturated C1-C20An alkyl group.
R2、R3And R4Equal to or different from each other, is a hydrogen atom or C optionally containing heteroatoms belonging to groups 13-17 of the periodic Table of the elements1-C40A hydrocarbyl group; preference is given toEarth, R2、R3And R4Equal to or different from each other, is a hydrogen atom or a linear or branched, cyclic or acyclic C1-C40Alkyl radical, C2-C40Alkenyl radical, C1-C40Alkynyl, C6-C40Aryl radical, C7-C40Alkylaryl or C7-C40An arylalkyl group; optionally containing heteroatoms belonging to groups 13-17 of the periodic Table of the elements; more preferably, R2、R3And R4Is a hydrogen atom or C1-C20An alkyl group.
R6、R7、R8、R9And R10Equal to or different from each other, is a hydrogen atom or C optionally containing heteroatoms belonging to groups 13-17 of the periodic Table of the elements1-C40A hydrocarbyl group; preferably, R6、R7、R8、R9And R10Equal to or different from each other, is a hydrogen atom or a linear or branched, cyclic or acyclic C1-C40Alkyl radical, C2-C40Alkenyl radical, C1-C40Alkynyl, C6-C40Aryl radical, C7-C40Alkylaryl or C7-C40An arylalkyl group; optionally containing heteroatoms belonging to groups 13-17 of the periodic Table of the elements; more preferably, R6、R7、R8、R9And R10At least one of which is not a hydrogen atom; preferably R6、R7、R8、R9And R10Is a hydrogen atom; preferably R8Is Cl-C40Alkyl, more preferably R8Is Cl-C40Alkyl, wherein the atom in the alpha-position is a secondary or tertiary carbon, such as isopropyl or tert-butyl.
As a preferred technical scheme: m is titanium, zirconium or hafnium; x is chlorine or Cl-C10An alkyl group; l is Si (CH)3)2，SiPh2，SiPhMe，SiMe(SiMe3)、CH2，(CH2)2Or C (CH)2)2；R1And R5Is straight-chain or branched, saturatedAnd or unsaturated C1-C20An alkyl group; r2、R3And R4Is a hydrogen atom or C1-C20An alkyl group; r8Is Cl-C40An alkyl group, wherein the atom in the alpha-position is a secondary or tertiary carbon.
The metallocene polypropylene catalyst can be used for olefin polymerization reaction, and can be polymerized at the temperature of-60-300 ℃ and the pressure of 0.5-3000 bar. Preference is given to temperatures of from 50 to 200 ℃ and in particular from 60 to 100 ℃ and pressures of from 5 to 100 bar and in particular from 15 to 70 bar. The average residence time is generally from 0.5 to 5 hours, preferably from 0.5 to 3 hours. It is also possible to use molar mass regulators, such as hydrogen, or customary additives, such as antistatics, for the polymerization.
Compared with the prior art, the invention has the following beneficial effects:
the invention provides a preparation method of a metallocene polypropylene catalyst, which enables active components to be distributed more uniformly by means of ultrasonic treatment, and the prepared metallocene polypropylene catalyst can improve the olefin polymerization activity, reduce the production cost of polymerization products and improve the polypropylene isotacticity.
Detailed Description
The present invention will be further described with reference to the following examples.
Comparative example 1
27mmol of MAO in toluene (10 wt%) were added to a flask under nitrogen, 1g of silica gel pretreated at 600 ℃ and 20mL of toluene were precisely weighed and stirred at room temperature for 2h, and the solid portion was washed 3 times with 20mL of toluene. Then, 34.7mg of dimethylsilanediylbis (2-methyl-4-phenylindenyl) zirconium dichloride was added thereto, and the mixture was stirred at 50 ℃ for 2 hours, and the solid portion was washed with 20mL of toluene 3 times, and the solvent was removed at room temperature to obtain the supported catalyst CAT 1.
Comparative example 2
27mmol of MAO in toluene (10 wt%) were added to a flask under nitrogen, 1g of silica gel pretreated at 600 ℃ and 20mL of toluene were precisely weighed and stirred at room temperature for 2h, and the solid portion was washed 3 times with 20mL of toluene. Then 34.7mg of dimethylsilanediylbis (2-methyl-4-phenylindenyl) zirconium dichloride was added, and the mixture was treated with ultrasonic waves at a frequency of 20KHz, stirred at room temperature for 2 hours, the solid portion was washed with 20mL of toluene 3 times, and the solvent was removed at room temperature to obtain the supported catalyst CAT 2.
Comparative example 3
In a catalyst preparation flask under nitrogen protection, 27mmol of MAO in toluene (10 wt%) was added followed by 34.7mg of dimethylsilanediylbis (2-methyl-4-phenylindenyl) zirconium dichloride, which was stirred at room temperature for 2 h. Adding 1g of silica gel pretreated at the temperature of 600 ℃ and 20mL of toluene which are accurately weighed into a catalyst preparation bottle, stirring for 2h at the temperature of 50 ℃, washing a solid part with 20mL of toluene for 3 times, and removing the solvent at room temperature to obtain the supported catalyst CAT 3.
Example 1
In a catalyst preparation flask under nitrogen protection, 27mmol of MAO in toluene (10 wt%) was added, followed by 34.7mg of dimethylsilanediylbis (2-methyl-4-phenylindenyl) zirconium dichloride, which was treated with ultrasound and stirred at room temperature for 2h at an ultrasonic frequency of 20 KHz. Adding 1g of silica gel pretreated at the temperature of 600 ℃ and 20mL of toluene which are accurately weighed into a catalyst preparation bottle, stirring for 2h at the temperature of 50 ℃, washing a solid part with 20mL of toluene for 3 times, and removing the solvent at room temperature to obtain the supported catalyst CAT 4.
Example 2
In a catalyst preparation flask under nitrogen protection, 27mmol of MAO in toluene (10 wt%) was added, followed by 34.7mg of dimethylsilanediylbis (2-methyl-4-phenylindenyl) zirconium dichloride, which was treated with ultrasound and stirred at room temperature for 2h at an ultrasonic frequency of 40 KHz. Adding 1g of silica gel pretreated at the temperature of 600 ℃ and 20mL of toluene which are accurately weighed into a catalyst preparation bottle, stirring for 2h at the temperature of 50 ℃, washing a solid part with 20mL of toluene for 3 times, and removing the solvent at room temperature to obtain the supported catalyst CAT 5.
Example 3
In a catalyst preparation flask under nitrogen protection, 27mmol of MAO in toluene (10 wt%) was added, followed by 34.7mg of dimethylsilanediylbis (2-methyl-4-phenylindenyl) zirconium dichloride, which was treated with ultrasound and stirred at room temperature for 2h at an ultrasonic frequency of 60 KHz. Adding 1g of silica gel pretreated at the temperature of 600 ℃ and 20mL of toluene which are accurately weighed into a catalyst preparation bottle, stirring for 2h at the temperature of 50 ℃, washing a solid part with 20mL of toluene for 3 times, and removing the solvent at room temperature to obtain the supported catalyst CAT 6.
Example 4
In a catalyst preparation flask under nitrogen protection, 27mmol of MAO in toluene (10 wt%) was added, followed by 34.7mg of dimethylsilanediylbis (2-methyl-4-phenylindenyl) zirconium dichloride, which was treated with ultrasound and stirred at room temperature for 2h at an ultrasonic frequency of 80 KHz. Adding 1g of silica gel pretreated at the temperature of 600 ℃ and 20mL of toluene which are accurately weighed into a catalyst preparation bottle, stirring for 2h at the temperature of 50 ℃, washing a solid part with 20mL of toluene for 3 times, and removing the solvent at room temperature to obtain the supported catalyst CAT 7.
Example 5
In a catalyst preparation flask under nitrogen protection, 27mmol of MAO in toluene (10 wt%) was added, followed by 34.7mg of dimethylsilanediylbis (2-methyl-4-phenylindenyl) zirconium dichloride, which was treated with ultrasound and stirred at room temperature for 2h at an ultrasonic frequency of 100 KHz. Adding 1g of silica gel pretreated at the temperature of 600 ℃ and 20mL of toluene which are accurately weighed into a catalyst preparation bottle, stirring for 2h at the temperature of 50 ℃, washing a solid part with 20mL of toluene for 3 times, and removing the solvent at room temperature to obtain the supported catalyst CAT 8.
Evaluation of catalyst:
the catalysts prepared in comparative examples 1 to 3 and examples 1 to 5 were polymerized by the following polymerization method.
10mmol TEA and 1200g of liquid propylene were charged to a 4L stainless steel jacketed kettle equipped with a magnetically driven stirrer and catalyst feeder. After stirring for 10 minutes, a total of 100mg of the catalyst was added through a catalyst feeder, and then polymerization was carried out at a constant temperature of 60 ℃ for 2 hours. Then the stirring was discontinued, the pressure in the kettle was vented and the polymer collected. The polymer was dried in a vacuum oven at 70 ℃ under vacuum.
NMR measurements were carried out by nuclear magnetic measurements of the polymer chain structure using a model 600M nuclear magnetic measurement from Burker, 75mg of polymer dissolved in 0.5mL of deuterated o-chlorobenzophenone. Isotacticity is defined as the% pentad [ mmmm ] -.
The polymerization evaluation results are shown in table 1.
TABLE 1 polymerization evaluation results
Of course, the foregoing is only a preferred embodiment of the invention and should not be taken as limiting the scope of the embodiments of the invention. The present invention is not limited to the above examples, and equivalent changes and modifications made by those skilled in the art within the spirit and scope of the present invention should be construed as being included in the scope of the present invention.
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