CN109553710B - Branched polyethylene and preparation method thereof - Google Patents
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Abstract
The invention discloses branched polyethylene and a preparation method thereof. The branched polyethylene consists of amorphous polyethylene and crystallizable polyethylene, wherein the mass fraction of the amorphous polyethylene is 40.1-83.4%, and the balance is crystallizable polyethylene. The branched polyethylene has high branching degree, the branched chain can reach 210 methyl groups/1000 carbon at most, the molecular weight is controllable within the range of 1000-400000g/mol, the mass fraction of amorphous polyethylene can be adjusted within the range of 40.1-83.4 percent, and the activity of the main catalyst of the preparation method of the branched polyethylene can reach 6.51x106g/(molNi. h), no second comonomer can be added in the preparation process, and the reaction condition is mild, so that the method is suitable for industrial production.
Description
Technical Field
The invention relates to branched polyethylene and a preparation method thereof, belonging to the field of branched polyethylene.
Background
Late transition metal catalysts, represented by nickel and palladium, exhibit characteristics that are quite different from those of early transition metal catalysts in catalyzing ethylene polymerization. The branched polyethylene can be prepared by only taking ethylene as the only polymerization monomer and adjusting the structure of the catalyst and the polymerization conditions. The morphology of the resulting polyethylene also changed from a conventional resin to a soft elastomer.
Guan introduces different substituents at para position of an aromatic ring connected with a-acenaphthylene diimine and nitrogen atoms, and researches the influence of the electronic effect of the substituents on the catalytic activity of the catalyst and the microstructure of the polymer. The result shows that the ligand containing strong electron-donating substituent can stabilize the catalyst and prolong the service life of the catalyst in the ethylene polymerization process, and the molecular weight of the polymer is increased; while the ligand containing electron-withdrawing substituent can reduce the molecular weight of the polymer and the catalytic activity of the catalyst in the ethylene polymerization process, but increase the branching degree of the polyethylene [ Organometallics,2011,30p2432-2452 ]. In order to further increase the steric hindrance and electron donating properties in the axial direction, Drexel h. et al designed cyclic nickel a-diimine and palladium catalysts which have a greatly improved thermal stability and a greatly increased branching degree of polyethylene, but a branching degree of less than 100 branches per 1000 carbon atoms, and which are relatively complicated to synthesize [ angelw. chem. int. ed.2004,43, 1821-.
Chinese patent CN104177528A discloses a method for preparing ethylene/long-chain alpha-olefin copolymer by using ethylene acenaphthene (alpha-diimine) nickel catalyst as main catalyst, the copolymer consists of a multi-block ethylene/long-chain alpha-olefin copolymer with a crystalline chain segment and an amorphous chain segment which are alternated, an amorphous ethylene homopolymer and a crystalline long-chain alpha-olefin homopolymer, wherein the weight content of the multi-block ethylene/long-chain alpha-olefin copolymer with the crystalline chain segments and the amorphous chain segments alternating is 17.2 to 25.4 percent, the weight content of the amorphous ethylene homopolymer is 34.3 to 59.3 percent, the weight content of the crystalline long-chain alpha-olefin homopolymer is 23.5 to 40.3 percent, and emphasizes that the prepared copolymer has the potential as a thermoplastic elastomer, however, tests show that the branching degree of the copolymer of the invention is less than 100 methyl groups/1000 carbons.
The Yuan-Jian super modifies a-diimine-Ni (II) complex and is used as a main catalyst for ethylene polymerization research. The results show that the modified bromine-containing a-diimine ligands and their nickel complexes are used in ethylene polymerization reactions, although the branching degree of the polyethylene is improved, but still less than 130 methyl groups per 1000 carbon atoms. [ chemical journal of higher school, 2011, 32(5), 1200-1204 ] [ catalytic journal, 2011, 32(3), 490-494 ]
Disclosure of Invention
In order to overcome the defects of low branching degree of polyethylene and the like in the prior art, the invention provides branched polyethylene and a preparation method thereof.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
the branched polyethylene consists of amorphous polyethylene in 40.1-83.4 wt% and crystallizable polyethylene in the balance.
The branched polyethylene has branches of 210 methyl groups/1000 carbons.
The weight average molecular weight of the branched polyethylene was 1000-400000 g/mol.
The content of short chain branches in the branched polyethylene can be controlled to be between 20 and 210 methyl groups/1000 carbons by controlling the content of amorphous polyethylene in the polyethylene. The short chain branch content of products with different purposes is required to be different, and the short chain branch content of 20-210 methyl groups/1000 carbons can be prepared by the method. The branched chain content is controlled by controlling the pressure and the catalyst concentration, the reaction pressure is increased, the branched chains are increased, the catalyst concentration is increased, and the branched chains are increased.
The short chain branch content is 70-150 methyl groups/1000C. Within this range, the polymerization reaction conditions are mild and easy to control.
The preparation method of the branched polyethylene comprises the following steps of sequentially connecting:
1) adding ethylene raw material into a reactor to make the pressure in the reactor reach 0.1-1.0 MPa;
2) controlling the temperature in the reactor to be 5-120 ℃, sequentially adding a cocatalyst and a main catalyst solution into the reactor, adjusting the pressure in the reactor to be 0.1-1.7 MPa, and starting a polymerization reaction;
3) after the polymerization reaction is finished, obtaining a polymer solution, inactivating a catalyst in the polymer solution by using an ethanol acidic solution, and then removing a solvent in the obtained solution material to obtain a polymer; the reaction device is provided with a temperature control system, the polymerization reaction is exothermic, the temperature in the reaction kettle fluctuates along with the reaction, when the temperature of the polymerization solution is kept stable and unchanged, the reaction is finished, and the polymerization reaction is finished within 4 +/-0.2 hours;
4) and (3) placing the obtained polymer in a vacuum drying oven to be dried to constant weight at the temperature of 60 +/-10 ℃ to obtain the branched polyethylene product.
The pressure in the reactor is adjusted by ethylene in step 2) above. The reaction temperature in step 2) is preferably 10 to 80 ℃ and more preferably 20 to 70 ℃. In the temperature range, the catalyst has high activity and is easy to control.
The structure of the main catalyst is as follows:
the structure of the catalyst is the prior structure, and the preparation is characterized in that the catalyst is used as a main catalyst of branched polyethylene.
The catalyst has high reaction activity for catalyzing the invention, and the number of polymer branched chains is large.
The activity of the main catalyst is not less than 6.51x106g/(molNi·h)。
In order to improve the dissolution effect of the catalyst and further improve the catalytic efficiency, the main catalyst solution is a toluene solution of a nickel coordination catalyst. Thus, the catalyst has good dissolving effect.
The cocatalyst is preferably at least one of Triethylaluminum (TEA), Triisobutylaluminum (TIBA), Methylaluminoxane (MAO), Modified Methylaluminoxane (MMAO) or dry methylaluminoxane (dMAO); the molar ratio of the aluminum in the cocatalyst to the nickel in the main catalyst, namely Al/Ni, is between 70 and 350. When the catalyst is used in combination with a main catalyst, the polymerization activity is high and the number of branched chains is large.
Further, MAO and MMAO are preferable as the co-catalyst. Therefore, the catalyst can be better matched with a main catalyst for use, and the polymerization activity is higher, and the branched chain is more. The polymer has weak crystallization ability due to more branched chains and high branching degree, and can be used as a thermoplastic elastomer and an additive in special fields.
In order to improve the product quality, in the step 3), the ethanol acidic solution comprises 95% of ethanol and 5% of hydrochloric acid with the concentration of 1mol/L, and the percentage is volume percentage.
The prior art is referred to in the art for techniques not mentioned in the present invention.
The branched polyethylene has high branching degree, the branched chain can reach 210 methyl groups/1000 carbon at most, the molecular weight is controllable within the range of 1000-400000g/mol, the mass fraction of amorphous polyethylene can be adjusted within the range of 40.1-83.4 percent, and the activity of the main catalyst of the preparation method of the branched polyethylene can reach 6.51x106g/(molNi. h), no second comonomer can be added in the preparation process, and the reaction condition is mild, so that the method is suitable for industrial production.
Detailed Description
In order to better understand the present invention, the following examples are further provided to illustrate the present invention, but the present invention is not limited to the following examples.
The main catalyst used in the examples is
Example 1
The ethylene raw material is added into a 250ml reaction kettle with a stirring device, a temperature control system, a pressure control system and a feeding system (no water and oxygen are ensured in the reaction system before use), the pressure is maintained at 0.1MPa, the temperature is controlled at 50 ℃, a cocatalyst of 0.7mmol MAO (Al/Ni ═ 70) and a main catalyst of 10 mu mol (concentration is 0.05mmol/L) of toluene solution are sequentially added to adjust the ethylene pressure in the reaction kettle to the required polymerization pressure of 0.5MPa, and the polymerization reaction is started. After the polymerization reaction is finished for 4 hours, the catalyst of the obtained polymer solution is deactivated and the solvent is removed by using a hydrochloric acid/ethanol solution with the volume fraction of 5% (the volume ratio of the hydrochloric acid to the ethanol is 5%, and the concentration of the hydrochloric acid is 1mol/L), the obtained polymer is placed in a vacuum drying oven to be dried to constant weight at 60 ℃, 15.11g of branched polyethylene product is obtained, and the activity of the catalyst is 1.51x106g/(molNi. h). The Mw of the product is tested to be 26.4x10 by taking 1,2, 4-trichlorobenzene as a solvent and utilizing a high-temperature gel chromatography-Fourier infrared spectroscopy coupling technology at the temperature of 150 DEG C4g/mol, branch content of 126 CH3and/1000C. Taking 50mg of a sample, and carrying out analysis type TREF (dichlorobenzene is taken as a solvent, heating to 150 ℃ for dissolution, stirring for dissolution for 90min, loading the solution to an A-TREF column, cooling the sample solution to 95 ℃ at 20 ℃/min, stabilizing for 45min, cooling to 35 ℃ at 0.5 ℃/min for crystallization, keeping the temperature at 35 ℃ for 10min, heating from 35 ℃ to 140 ℃ at 1 ℃/min for elution of the sample), wherein the mass fraction of elution components at 35 ℃ (mainly amorphous polyethylene) is 63.4% in the analysis result.
Example 2
Polymerization conditions were the same as in example 1 except that TEA (triethylaluminum) was used as a co-catalyst in place of MAO, and the polymerization pressure was controlled to 0.21 MPa. 0.91g of branched polyethylene product and 0.91x10 of catalyst activity are obtained5g/(molNi. h). The Mw of the product is 8.07x10 by taking 1,2, 4-trichlorobenzene as a solvent and testing the product by using a high-temperature gel chromatography-Fourier infrared spectroscopy coupling technology at the temperature of 150 DEG C4g/mol, branched chain content of 75.5 CH3and/1000C. 50mg of sample is taken and analyzed by an analytical TREF, and the mass fraction of the elution component at 35 ℃ is 51.1 percent according to the analysis result.
Example 3
Polymerization conditions were the same as in example 1 except that MMAO was used instead of MAO. 21.55g of branched polyethylene product with catalyst activity of 2.16x10 is obtained6g/(molNi. h). The Mw of the product is tested to be 24.68x10 by taking 1,2, 4-trichlorobenzene as a solvent and utilizing a high-temperature gel chromatography-Fourier infrared spectroscopy coupling technology under the condition of 150 DEG C4g/mol, a branched chain content of 153.5 CH3and/1000C. 50mg of a sample is analyzed by an analytical TREF (TREF analysis), and the weight fraction of the elution component at 35 ℃ is 72.16%.
Example 4
Polymerization conditions As in example 1, MMAO alone was used in place of MAO, and the polymerization pressure was controlled to 1.5MPa to yield 65.1g of a branched polyethylene product having a catalyst activity of 6.51X106g/(molNi. h). The Mw of the product is 39.75x10 by taking 1,2, 4-trichlorobenzene as a solvent and testing the product by using a high-temperature gel chromatography-Fourier transform infrared spectroscopy coupling technology at the temperature of 150 DEG C4g/mol, a branched chain content of 149.5 CH3and/1000C. 50mg of a sample is analyzed by an analytical TREF (TREF analysis), and the weight fraction of the elution component at 35 ℃ is 68.41%.
Example 5
Polymerization conditions As in example 1, only MMAO was used in place of MAO, the reaction temperature was controlled at 30 ℃ and the polymerization pressure was controlled at 0.15MPa to obtain 5.64g of a branched polyethylene product having a catalyst activity of 5.64X105g/(molNi. h). The Mw of the product is 14.31x10 by taking 1,2, 4-trichlorobenzene as a solvent and testing the product by using a high-temperature gel chromatography-Fourier infrared spectroscopy coupling technology at the temperature of 150 DEG C4g/mol, branch content of 124.3 CH3and/1000C. 50mg of the sample is analyzed by an analytical TREF, and the mass fraction of the elution component at 35 ℃ is 73.4 percent.
Example 6
Polymerization conditions as in example 3, except that the reaction temperature was controlled to 5 ℃ alone, a branched polyethylene product, 0.11g., having a catalyst activity of 0.11X10, was obtained5g/(molNi. h). 1,2, 4-trichlorobenzene is used as a solvent, and high-temperature gel chromatography-Fourier infrared spectroscopy is utilized at the temperature of 150 DEG CThe product Mn is 0.04Kg/mol, the branched chain content is 52.5 CH by the technical test3and/1000C. 50mg of sample is taken and analyzed by an analytical TREF, and the mass fraction of the elution component at 35 ℃ is 40.1 percent according to the analysis result.
Example 7
Polymerization conditions as in example 3, except that the reaction temperature was controlled to 80 ℃ alone, a branched polyethylene product, 1.41g., having a catalyst activity of 1.41X10, was obtained5g/(molNi. h). 1,2, 4-trichlorobenzene is used as a solvent, and the Mw of the product is 16.39Kg/mol and the branched chain content is 209.5 CH by utilizing a high-temperature gel chromatography-Fourier infrared spectroscopy combined technology test under the condition of 150 DEG C3and/1000C. 50mg of sample is taken and analyzed by an analytical TREF, and the mass fraction of the elution component at 35 ℃ is 83.4 percent.
Example 8
Polymerization conditions as in example 3, except that Al/Ni was raised to 70 to 100, gave a branched polyethylene product of 19.72 having a catalyst activity of 1.97x106g/(molNi. h). The Mw of the product is tested to be 22.78x10 by taking 1,2, 4-trichlorobenzene as a solvent and utilizing a high-temperature gel chromatography-Fourier infrared spectroscopy coupling technology at the temperature of 150 DEG C4g/mol, branched chain content 131.5 CH3and/1000C. 50mg of the sample was analyzed by analytical TREF, and the mass fraction of the 35 ℃ eluted component (mainly amorphous polyethylene) was 69.7%.
Example 9
Polymerization conditions as in example 3, except that Al/Ni was raised to 70 to 200, gave a branched polyethylene product of 14.48 having a catalyst activity of 1.45x106g/(molNi. h). 1,2, 4-trichlorobenzene is used as a solvent, and the Mw of the product is 20.69g/mol and the branched chain content is 128.7 CH by utilizing a high-temperature gel chromatography-Fourier infrared spectroscopy combined technology test under the condition of 150 DEG C3and/1000C. 50mg of sample is taken and analyzed by an analytical TREF, and the mass fraction of the elution component at 35 ℃ is 66.1 percent according to the analysis result.
Example 10
Polymerization conditions as in example 3, except that Al/Ni was raised to 350, yielding 8.58g. of branched polyethylene product with a catalyst activity of 8.58x105g/(molNi. h). 1,2, 4-trichlorobenzene is used as a solvent, and a high-temperature gel chromatography-Fourier infrared spectroscopy combined technology is utilized at the temperature of 150 DEG CThe Mw of the test product was 16.39g/mol and the branched content was 99.2 CH3and/1000C. 50mg of the sample was analyzed by analytical TREF, and the mass fraction of the 35 ℃ eluted component (mainly amorphous polyethylene) was 57.1%.
Claims (6)
1. A process for the preparation of branched polyethylene, characterized in that: comprises the following steps that: 1) adding ethylene raw material into a reactor to make the pressure in the reactor reach 0.1-1.0 MPa;
2) controlling the temperature in the reactor to be 30-120 ℃, sequentially adding a cocatalyst and a main catalyst solution into the reactor, adjusting the pressure in the reactor to be 0.1-1.7 MPa, and starting a polymerization reaction;
3) after the polymerization reaction is finished, obtaining a polymer solution, inactivating a catalyst in the polymer solution by using an ethanol acidic solution, and then removing a solvent in the obtained solution material to obtain a polymer;
4) placing the obtained polymer in a vacuum drying oven to be dried to constant weight at the temperature of 60 +/-10 ℃ to obtain the branched polyethylene product;
the branched polyethylene consists of amorphous polyethylene and crystallizable polyethylene, wherein the amorphous polyethylene accounts for 51.1-83.4% of the mass fraction, and the crystallizable polyethylene accounts for the balance; the weight average molecular weight of the branched polyethylene is 1000-400000 g/mol; the branched polyethylene has a short chain branch content of 75.5 to 210 methyl groups per 1000 carbons.
2. The method of claim 1, wherein: the structure of the main catalyst is as follows:
3. the method of claim 1 or 2, wherein: the activity of the main catalyst is not less than 6.51x106g／(molNi•h)。
4. The method of claim 1 or 2, wherein: the main catalyst solution is a toluene solution of a nickel coordination catalyst.
5. The method of claim 1 or 2, wherein: the cocatalyst is at least one of triethyl aluminum, triisobutyl aluminum, methylaluminoxane, modified methylaluminoxane or dimethyl aluminoxane; the molar ratio of the aluminum in the cocatalyst to the nickel in the main catalyst, namely Al/Ni, is between 70 and 350.
6. The method of claim 1 or 2, wherein: in the step 3), the ethanol acidic solution comprises 95% of absolute ethanol and 5% of hydrochloric acid with the concentration of 1mol/L, and the ratio of the absolute ethanol to the hydrochloric acid is the volume ratio.
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1583807A (en) * | 2004-06-09 | 2005-02-23 | 中山大学 | Multinuclear acenaphthene diimine nickle catalyst for synthesis of branched polyethylene |
| CN1911970A (en) * | 2006-08-18 | 2007-02-14 | 中国科学院长春应用化学研究所 | Method for preparing bipeak molecular weight distribution polyethylene by calalyst comixing system |
| CN101392036A (en) * | 2008-11-05 | 2009-03-25 | 河北工业大学 | Metallocene domino catalytic system for preparing branched polyethylene using ethylene as only monomer and use thereof |
| CN102060944A (en) * | 2010-12-17 | 2011-05-18 | 西北师范大学 | Alpha-diimine nickel (II) olefin polymerization catalyst as well as preparation method and application thereof |
| CN102250152A (en) * | 2011-05-26 | 2011-11-23 | 中山大学 | Preparation method and application of amido-imine nickel vinyl polymerization catalyst |
| CN102786435A (en) * | 2011-05-16 | 2012-11-21 | 中国科学院上海有机化学研究所 | Catalysis systems for preparing highly branched alkane by using olefin |
| CN102827312A (en) * | 2012-08-03 | 2012-12-19 | 浙江大学 | Ethylidene acenaphthene (alpha-diimine) nickel olefin catalyst, and preparation method and application thereof |
| CN105622803A (en) * | 2014-11-17 | 2016-06-01 | 中国科学院化学研究所 | Novel purpose of random hyperbranched polyethylene |
| CN106589181A (en) * | 2016-11-15 | 2017-04-26 | 浙江大学 | Multi-block branched polyethylene and preparation method thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090163666A1 (en) * | 2007-12-21 | 2009-06-25 | David John Lohse | Polymer compositions exhibiting enhanced flow-induced crystallization |
-
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- 2017-09-27 CN CN201710891024.4A patent/CN109553710B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1583807A (en) * | 2004-06-09 | 2005-02-23 | 中山大学 | Multinuclear acenaphthene diimine nickle catalyst for synthesis of branched polyethylene |
| CN1911970A (en) * | 2006-08-18 | 2007-02-14 | 中国科学院长春应用化学研究所 | Method for preparing bipeak molecular weight distribution polyethylene by calalyst comixing system |
| CN101392036A (en) * | 2008-11-05 | 2009-03-25 | 河北工业大学 | Metallocene domino catalytic system for preparing branched polyethylene using ethylene as only monomer and use thereof |
| CN102060944A (en) * | 2010-12-17 | 2011-05-18 | 西北师范大学 | Alpha-diimine nickel (II) olefin polymerization catalyst as well as preparation method and application thereof |
| CN102786435A (en) * | 2011-05-16 | 2012-11-21 | 中国科学院上海有机化学研究所 | Catalysis systems for preparing highly branched alkane by using olefin |
| CN102250152A (en) * | 2011-05-26 | 2011-11-23 | 中山大学 | Preparation method and application of amido-imine nickel vinyl polymerization catalyst |
| CN102827312A (en) * | 2012-08-03 | 2012-12-19 | 浙江大学 | Ethylidene acenaphthene (alpha-diimine) nickel olefin catalyst, and preparation method and application thereof |
| CN105622803A (en) * | 2014-11-17 | 2016-06-01 | 中国科学院化学研究所 | Novel purpose of random hyperbranched polyethylene |
| CN106589181A (en) * | 2016-11-15 | 2017-04-26 | 浙江大学 | Multi-block branched polyethylene and preparation method thereof |
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