Preparation method of efficient polypropylene catalyst

Abstract

The invention discloses a preparation method of an efficient polypropylene catalyst, and relates to the technical field of catalysts, the preparation method comprises the following steps: S1, preparing a nano-carrier; s2, preparing a catalyst precursor; s3, carrying out continuous reaction; according to the preparation method disclosed by the invention, nano silicon dioxide is adopted as a catalyst carrier, and functional groups are introduced through a surface modification technology, so that the specific surface area and active sites are increased, and the catalytic activity is improved; a novel organic aluminum compound is introduced as a cocatalyst, MAO can effectively activate a main catalyst, meanwhile, the rate of polymerization reaction and the isotacticity of polypropylene are improved, and the catalytic activity and selectivity are improved; and pumping the catalyst precursor and the nano-carrier solution into the micro-channel reactor for reaction to obtain the high-efficiency polypropylene catalyst, so that the production efficiency and the consistency are improved.

Description

Technical Field

[0001] The invention relates to the technical field of catalysts, and in particular to a method for preparing a high-efficiency polypropylene catalyst. Background Art

[0002] Polypropylene is a crystalline polymer with a regular structure. It is non-toxic, odorless, and lightweight. It has the advantages of easy processing, high impact strength, and good electrical insulation properties. It is widely used in the automotive industry, packaging industry, electronics and electrical, building materials, and other fields.

[0003] With the continuous development of science and technology, the requirements for polypropylene production capacity and production efficiency are also increasing. Therefore, while reducing production costs, improving the production efficiency of polypropylene is the current research direction of technicians. Not only that, the working temperature of high-efficiency polypropylene catalysts is around 150°C and cannot react at higher temperatures.

[0004] In summary, a method for preparing a high-efficiency polypropylene catalyst was designed. Summary of the invention

[0005] In order to overcome the above-mentioned shortcomings, the present invention provides a method for preparing a high-efficiency polypropylene catalyst.

[0006] The present invention achieves the above-mentioned purpose through the following technical solutions: A method for preparing a high-efficiency polypropylene catalyst, characterized in that it comprises the following steps: S1, preparing nano-carriers, dispersing nano-SiO2 in anhydrous ethanol, adding silane coupling agent, reacting at a temperature of 60°C for 2 hours, and obtaining surface-modified nano-carriers; S2, preparing a catalyst precursor, dissolving the main catalyst and the co-catalyst in an ionic liquid at a molar ratio of 1:50 to 1:300, and uniformly mixing them by ultrasonic dispersion to form a catalyst precursor, wherein the co-catalyst is methylaluminoxane MAO; S3, continuous reaction, pumping the catalyst precursor and the nanocarrier solution into the microchannel reactor for reaction to obtain a high-efficiency polypropylene catalyst; S4, surface coating, immersing the high-efficiency polypropylene catalyst in the precursor solution and forming a surface coating layer through heat treatment.

[0007] Preferably, the main catalyst is one of ZrCl4, Cp2TiCl2, VCl4 or CrCl3, the molar ratio of ZrCl4 to MAO is 1:50 to 1:200, the molar ratio of Cp2TiCl2 to MAO is 1:100 to 1:300, the molar ratio of VCl4 to MAO is 1:50 to 1:150, and the molar ratio of CrCl3 to MAO is 1:80 to 1:200.

[0008] Preferably, the ionic liquid is 1-butyl-3-methylimidazolium hexafluorophosphate. The ionic liquid is almost non-volatile, which can reduce the pollution of organic solvents to the environment and can be recovered and reused by distillation or extraction to reduce resource waste.

[0009] Preferably, in step S3, the reaction time of the continuous reaction is 20 to 50 minutes, and the reaction temperature is 30 to 60°C.

[0010] Preferably, in step S4, the reaction temperature of the heat treatment is between 300 and 400° C., and the heat treatment time is 2 to 3 hours.

[0011] Preferably, in step S4, the precursor solution is a magnesium oxide solution, and magnesium oxide is a high temperature resistant material, so that the high efficiency polypropylene catalyst can adapt to high temperature reaction conditions.

[0012] Preferably, the method further includes step S5, namely, functionalization treatment, mixing the flame retardant monomer with a high-efficiency polypropylene catalyst, and generating a multifunctional polypropylene material through in-situ polymerization, thereby giving the polypropylene material a flame retardant function.

[0013] The invention has the following beneficial effects: in the preparation method of the high-efficiency polypropylene catalyst, nano-silicon dioxide is used as a catalyst carrier, and functional groups are introduced through surface modification technology (such as silanization treatment) to increase the specific surface area and active sites, thereby improving the catalytic activity; a new type of organic aluminum compound (such as methylaluminoxane, MAO) is introduced as a co-catalyst, and MAO can effectively activate the main catalyst, while increasing the polymerization reaction rate and the isotacticity of polypropylene, thereby improving the catalytic activity and selectivity; a catalyst precursor and a nano-carrier solution are pumped into a microchannel reactor for reaction to obtain a high-efficiency polypropylene catalyst, thereby improving production efficiency and consistency. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 It is a preparation step diagram of the present invention. DETAILED DESCRIPTION

[0015] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0016] like Figure 1 As shown, a method for preparing a high-efficiency polypropylene catalyst comprises the following steps: S1. Prepare nanocarriers, disperse nano-SiO2 in anhydrous ethanol, add silane coupling agent, and react at 60°C for 2 hours to obtain surface-modified nanocarriers, which can increase specific surface area and active sites; S2, preparing a catalyst precursor, dissolving the main catalyst and the co-catalyst in an ionic liquid at a molar ratio of 1:50 to 1:300, and uniformly mixing them by ultrasonic dispersion to form a catalyst precursor, wherein the co-catalyst is methylaluminoxane MAO, which improves the catalytic activity and selectivity; S3, continuous reaction, pumping the catalyst precursor and nanocarrier solution into the microchannel reactor for reaction to obtain a high-efficiency polypropylene catalyst, thereby improving production efficiency and consistency; S4, surface coating, immersing the high-efficiency polypropylene catalyst in a precursor solution, and forming a surface coating layer through heat treatment, so that the high-efficiency polypropylene catalyst can adapt to high-temperature reaction conditions; S5. Functionalization treatment: mixing flame retardant monomers with high-efficiency polypropylene catalysts to generate multifunctional polypropylene materials through in-situ polymerization, thereby giving polypropylene materials flame retardant functions.

[0017] As a specific embodiment 1: A method for preparing a high-efficiency polypropylene catalyst comprises the following steps: S1. Prepare nanocarriers, disperse nano-SiO2 in anhydrous ethanol, add silane coupling agent, and react at 60°C for 2 hours to obtain surface-modified nanocarriers, which can increase specific surface area and active sites; S2, preparing a catalyst precursor, dissolving the main catalyst ZrCl4 and the co-catalyst MAO in a molar ratio of 1:50 to 1:200 in the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate, and uniformly mixing them by ultrasonic dispersion to form a catalyst precursor, wherein the co-catalyst is methylaluminoxane MAO, to improve the catalytic activity and selectivity; S3, continuous reaction, pumping the catalyst precursor and nanocarrier solution into the microchannel reactor for reaction, the continuous reaction time is 20 minutes, the reaction temperature is 50°C, and a high-efficiency polypropylene catalyst is obtained, thereby improving production efficiency and consistency; S4, surface coating, immersing the high-efficiency polypropylene catalyst in the precursor solution magnesium oxide solution, and forming a surface coating layer through heat treatment, so that the high-efficiency polypropylene catalyst can adapt to high-temperature reaction conditions. The reaction temperature of the heat treatment is between 300°C and the heat treatment time is 2 hours.

[0018] S5. Functionalization treatment: mixing flame retardant monomers with high-efficiency polypropylene catalysts to generate multifunctional polypropylene materials through in-situ polymerization, thereby giving polypropylene materials flame retardant functions.

[0019] As a specific embodiment 2: A method for preparing a high-efficiency polypropylene catalyst comprises the following steps: S1. Prepare nanocarriers, disperse nano-SiO2 in anhydrous ethanol, add silane coupling agent, and react at 60°C for 2 hours to obtain surface-modified nanocarriers, which can increase specific surface area and active sites; S2, preparing a catalyst precursor, dissolving the main catalyst Cp2TiCl2 and the co-catalyst MAO in a molar ratio of 1:100 to 1:300 in the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate, and uniformly mixing them by ultrasonic dispersion to form a catalyst precursor, wherein the co-catalyst is methylaluminoxane MAO, to improve the catalytic activity and selectivity; S3, continuous reaction, pumping the catalyst precursor and nanocarrier solution into the microchannel reactor for reaction, the continuous reaction time is 30 minutes, the reaction temperature is 50°C, and a high-efficiency polypropylene catalyst is obtained, thereby improving production efficiency and consistency; S4, surface coating, immersing the high-efficiency polypropylene catalyst in the precursor solution magnesium oxide solution, and forming a surface coating layer through heat treatment, so that the high-efficiency polypropylene catalyst can adapt to high-temperature reaction conditions. The reaction temperature of the heat treatment is between 300°C and the heat treatment time is 3 hours.

[0020] S5. Functionalization treatment: mixing flame retardant monomers with high-efficiency polypropylene catalysts to generate multifunctional polypropylene materials through in-situ polymerization, thereby giving polypropylene materials flame retardant functions.

[0021] As a specific embodiment three: A method for preparing a high-efficiency polypropylene catalyst comprises the following steps: S1. Prepare nanocarriers, disperse nano-SiO2 in anhydrous ethanol, add silane coupling agent, and react at 60°C for 2 hours to obtain surface-modified nanocarriers, which can increase specific surface area and active sites; S2, preparing a catalyst precursor, dissolving the main catalyst VCl4 and the co-catalyst MAO in a molar ratio of 1:50 to 1:150 in the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate, and uniformly mixing them by ultrasonic dispersion to form a catalyst precursor, wherein the co-catalyst is methylaluminoxane MAO, to improve the catalytic activity and selectivity; S3, continuous reaction, pumping the catalyst precursor and nanocarrier solution into the microchannel reactor for reaction, the continuous reaction time is 30 minutes, the reaction temperature is 50°C, and a high-efficiency polypropylene catalyst is obtained, thereby improving production efficiency and consistency; S4, surface coating, immersing the high-efficiency polypropylene catalyst in the precursor solution magnesium oxide solution, and forming a surface coating layer through heat treatment, so that the high-efficiency polypropylene catalyst can adapt to high-temperature reaction conditions. The reaction temperature of the heat treatment is between 300°C and the heat treatment time is 3 hours.

[0022] S5. Functionalization treatment: mixing flame retardant monomers with high-efficiency polypropylene catalysts to generate multifunctional polypropylene materials through in-situ polymerization, thereby giving polypropylene materials flame retardant functions.

[0023] As a specific embodiment 4: A method for preparing a high-efficiency polypropylene catalyst comprises the following steps: S1. Prepare nanocarriers, disperse nano-SiO2 in anhydrous ethanol, add silane coupling agent, and react at 60°C for 2 hours to obtain surface-modified nanocarriers, which can increase specific surface area and active sites; S2, preparing a catalyst precursor, dissolving the main catalyst CrCl3 and the co-catalyst MAO in a molar ratio of 1:80 to 1:200 in the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate, and uniformly mixing them by ultrasonic dispersion to form a catalyst precursor, wherein the co-catalyst is methylaluminoxane MAO, to improve the catalytic activity and selectivity; S3, continuous reaction, pumping the catalyst precursor and nanocarrier solution into the microchannel reactor for reaction, the continuous reaction time is 30 minutes, the reaction temperature is 50°C, and a high-efficiency polypropylene catalyst is obtained, thereby improving production efficiency and consistency; S4, surface coating, immersing the high-efficiency polypropylene catalyst in the precursor solution magnesium oxide solution, and forming a surface coating layer through heat treatment, so that the high-efficiency polypropylene catalyst can adapt to high-temperature reaction conditions. The reaction temperature of the heat treatment is between 300°C and the heat treatment time is 3 hours.

[0024] S5. Functionalization treatment: mixing flame retardant monomers with high-efficiency polypropylene catalysts to generate multifunctional polypropylene materials through in-situ polymerization, thereby giving polypropylene materials flame retardant functions.

[0025] The above is based on the present invention as an inspiration. Through the above description, relevant staff can make various changes and modifications without departing from the technical idea of ​​this invention. The technical scope of this invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A method for preparing a high-efficiency polypropylene catalyst, characterized in that: The following steps are involved: S1, preparing nano-carriers, dispersing nano-SiO2 in anhydrous ethanol, adding silane coupling agent, reacting at a temperature of 60°C for 2 hours, and obtaining surface-modified nano-carriers; S2, preparing a catalyst precursor, dissolving the main catalyst and the co-catalyst in an ionic liquid at a molar ratio of 1:50 to 1:300, and uniformly mixing them by ultrasonic dispersion to form a catalyst precursor, wherein the co-catalyst is methylaluminoxane MAO; S3, continuous reaction, pumping the catalyst precursor and the nanocarrier solution into the microchannel reactor for reaction to obtain a high-efficiency polypropylene catalyst; S4, surface coating, immersing the high-efficiency polypropylene catalyst in the precursor solution and forming a surface coating layer through heat treatment.

2. The method for preparing a high-efficiency polypropylene catalyst according to claim 1, characterized in that: The main catalyst is one of ZrCl4, Cp2TiCl2, VCl4 or CrCl3, the molar ratio of ZrCl4 to MAO is 1:50 to 1:200, the molar ratio of Cp2TiCl2 to MAO is 1:100 to 1:300, the molar ratio of VCl4 to MAO is 1:50 to 1:150, and the molar ratio of CrCl3 to MAO is 1:80 to 1:

200.

3. The method for preparing a high-efficiency polypropylene catalyst according to claim 1, characterized in that: The ionic liquid is 1-butyl-3-methylimidazolium hexafluorophosphate.

4. The method for preparing a high-efficiency polypropylene catalyst according to claim 1, characterized in that: In the step S3, the reaction time of the continuous reaction is 20 to 50 minutes, and the reaction temperature is 30 to 60°C.

5. The method for preparing a high-efficiency polypropylene catalyst according to claim 1, characterized in that: In the step S4, the reaction temperature of the heat treatment is between 300 and 400° C., and the heat treatment time is 2 to 3 hours.

6. The method for preparing a high-efficiency polypropylene catalyst according to claim 1, characterized in that: In the step S4, the precursor solution is magnesium oxide solution.

7. The method for preparing a high-efficiency polypropylene catalyst according to claim 1, characterized in that: The method also includes step S5, S5, functionalization treatment, mixing the flame retardant monomer with the high-efficiency polypropylene catalyst, and generating a multifunctional polypropylene material through in-situ polymerization.

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