CN1292007C - Bi active component polyolefin catalyst, and its preparing method and use - Google Patents

Abstract

A dual-active component polyolefin catalyst, comprising carrier MgCl ₂ n(ROH), TiCl ₄ and pyridine-2-alkylimine titanium tetrachloride shown in formula (I), R ₁ in formula (I) , R ₂ are single substituents or multiple substituents on the pyridine ring and aniline ring, each independently selected from hydrogen, C ₁ -C ₆ alkyl or C ₇ -C ₈ aralkyl. The catalyst has double active centers, and can be used as an olefin polymerization catalyst to prepare olefin polymers with bimodal or wide molecular weight distribution, and the polymers have a single high melting point and high crystallinity.

Description

Dual active component polyolefin catalyst, preparation method and application

technical field

The present invention is an olefin polymerization catalyst loaded with dual active components and a preparation method, specifically, a catalyst and a preparation method with _TiCl4 and a nitrogen-containing bidentate coordinated titanium compound as active components in the ligand. application.

Background technique

During the processing of polyolefin materials, the molecular weight of polyolefin, such as the molecular weight and molecular weight distribution of polyethylene, has a great influence on the processing performance. When the weight-average molecular weight of polyolefin is constant, the molecular weight distribution determines its physical properties, mechanical properties and rheological properties. A wide molecular weight distribution is beneficial to material processing, while a narrow molecular weight distribution is not conducive to material processing. Recently developed non-metallocene catalysts containing heteroatoms in their ligands have high polymerization activity, but expensive methylaluminoxane is required as a cocatalyst for polymerization. As disclosed in CN1331252A, a kind of transition metal complex with a bidentate coordinated pyridine imine as a ligand, when the complex is used as a catalyst for ethylene polymerization, can obtain a high molecular weight polymer product, but the molecular weight distribution of the product is still not enough Wide, especially when it is made into a supported catalyst, the molecular weight distribution of the obtained polymerization product is relatively narrow.

One approach to improving the molecular weight distribution of polymers is to prepare polymers with bimodal or broad molecular weight distributions. The polymer consists of two polyolefins with different molecular weight distributions, that is to say a polyolefin with a relatively high molecular weight distribution and a polyolefin with a relatively low molecular weight distribution. The advantage of polyolefins with bimodal or broad molecular weight distribution is that it retains the good properties of the high molecular weight fraction, including tensile strength, elongation at break, impact and puncture resistance, and improves processing due to the presence of the low molecular weight fraction performance, especially extrusion performance. In the prior art, polymers with bimodal or broad molecular weight distribution are often prepared by preparing supported catalysts with two active components.

Contents of the invention

The object of the present invention is to provide a polyolefin catalyst containing two active components and a preparation method thereof. The catalyst is used for olefin polymerization, has high polymerization activity, and the produced polyolefin has a wide molecular weight distribution.

The dual active component polyolefin catalyst provided by the present invention comprises carrier MgCl ₂ n(ROH), TiCl ₄ and pyridine-2-alkylimine titanium tetrachloride represented by formula (I),

In formula (I), R ₁ and R ₂ are single or multiple substituents on the pyridine ring and aniline ring, each independently selected from hydrogen, C ₁ -C ₆ alkyl or C ₇ -C ₈ aromatic Alkyl group, n in the carrier MgCl ₂ n(ROH) is 0.1-2.0, R is a C ₂ -C ₈ alkyl group; the magnesium content in the catalyst is 5-20% by mass, and the titanium content is 0.5-12% by mass , the molar ratio of TiCl ₄ to pyridine-2-alkylimine tetrachloride titanium is 0.1 to 5.0:1.

The present invention uses two active components to prepare a supported catalyst, so that the catalyst has dual active centers, and therefore, a bimodal or broad molecular weight distribution polymer can be produced, which has a single high melting point and high crystallinity , The degree of crystallinity is generally greater than 65%, and the highest reaches 87.1%.

Description of drawings

Figure 1 is a differential thermal scanning (DSC) graph of a polymer prepared with the catalyst of the present invention.

Figure 2 is a gel permeation chromatogram (GPC) graph of a polymer prepared with the catalyst of the present invention.

Detailed ways

The two active components in the catalyst of the present invention are the conventional Ziegler-Natta catalyst component TiCl ₄ , and the other is the titanium compound pyridine-2-alkylimine tetrachloride of bidentate coordination. The molar ratio of TiCl ₄ to pyridine-2-imide titanium tetrachloride in the catalyst should be controlled within a certain range, preferably 0.4-3.0:1. If the content of TiCl ₄ in the catalyst is too high, the molecular weight distribution of the polymer will be narrowed; if the content of TiCl ₄ is too low, the catalytic activity will decrease significantly. The titanium content in the catalyst is preferably 2.0-5.0% by mass, and the magnesium content is preferably 5-13% by mass.

In the active component pyridine-2-alkylimine titanium tetrachloride, R _{and R} are substituents on the pyridine ring and aniline aromatic ring respectively, and the number of substituent _R on the pyridine ring can be 1 to 3, and the substituent position is preferably the 4 or 6 position of the pyridine ring. The number of substituents R ₂ on the aromatic ring of aniline is 1-6, preferably 1-3, and the substituent positions are preferably located at positions 2, 4, and 6 of the benzene ring. _R1 and _R2 are preferably hydrogen, _C1 - _C4 alkyl, phenyl or benzyl, more preferably hydrogen, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl base. R ₃ is a substituent on the imine carbon atom, preferably hydrogen, methyl or ethyl.

The ligand compound in the pyridine-2-alkylimine titanium tetrachloride used in the present invention is preferably: N-(2,6-dimethylphenyl)-2-pyridinemethanimine, N-(2,6 -Diethylphenyl)-2-pyridinemethimine, N-(2,6-diisopropylphenyl)-2-pyridinemethimine, N-(2,6-diisobutylphenyl )-2-pyridylmethine, N-(2,6-di-tert-butylphenyl)-2-pyridylmethine, N-(2,6-dibenzylphenyl)-2-pyridylmethine Amine, N-(2,4-dimethylphenyl)-2-pyridinemethanimine, N-(2,4-diethylphenyl)-2-pyridinemethanimine, N-(2,4 -Diisopropylphenyl)-2-pyridinemethanimine, N-(2,4-diisobutylphenyl)-2-pyridinemethanimine, N-(2,4-di-tert-butylbenzene Base)-2-pyridinemethanimine, N-(2,4-dibenzylphenyl)-2-pyridinemethanimine;

N-(2-ethylphenyl)-2-pyridinemethanimine, N-(2-n-propylphenyl)-2-pyridinemethanimine, N-(2-isopropylphenyl)-2 -Pyridine imine, N-(2-n-butylphenyl)-2-pyridine imine, N-(2-isobutylphenyl)-2-pyridine imine, N-(2-tert Butylphenyl)-2-pyridinemethimine, N-(2-benzylphenyl)-2-pyridinemethimine;

N-(2-methyl-6-ethylphenyl)-2-pyridinemethanimine, N-(2-methyl-6-isopropylphenyl)-2-pyridinemethanimine, N-( 2-methyl-6-isobutylphenyl)-2-pyridinemethanimine, N-(2-methyl-6-tert-butylphenyl)-2-pyridinemethanimine, N-(2- Methyl-6-benzylphenyl)-2-pyridinemethanimine, N-(2-ethyl-6-isopropylphenyl)-2-pyridinemethanimine, N-(2-ethyl- 6-isobutylphenyl)-2-pyridinemethimine, N-(2-ethyl-6-tert-butylphenyl)-2-pyridinemethimine, N-(2-ethyl-6- Benzylphenyl)-2-pyridinemethanimine, N-(2-isopropyl-6-isobutylphenyl)-2-pyridinemethanimine, N-(2-isopropyl-6-tert Butylphenyl)-2-pyridinemethanimine, N-(2-isopropyl-6-benzylphenyl)-2-pyridinemethanimine, N-(2-isobutyl-6-tert-butyl phenyl)-2-pyridinemethanimine, N-(2-isobutyl-6-benzylphenyl)-2-pyridinemethanimine, N-(2-tert-butyl-6-benzylbenzene Base) -2-pyridyl imine;

N-(2,4,6-trimethylphenyl)-2-pyridinemethanimine, N-(2,4,6-triethylphenyl)-2-pyridinemethanimine, N-(2 , 4,6-triisopropylphenyl)-2-pyridinemethimine, N-(2,4,6-triisobutylphenyl)-2-pyridinemethimine, N-(2,4 , 6-tri-tert-butylphenyl)-2-pyridinemethanimine, N-(2-methyl-4,6-dimethylphenyl)-2-pyridinemethanimine, N-(2-methyl Base-4,6-diethylphenyl)-2-pyridinemethanimine, N-(2-methyl-4,6-dibenzylphenyl)-2-pyridinemethanimine, N-(2 -isopropyl-4,6-dimethylphenyl)-2-pyridinemethimine, N-(2-isopropyl-4,6-diethylphenyl)-2-pyridinemethimine, N-(2,4-diisopropyl-6-methylphenyl)-2-pyridinemethimine, N-(2,4-di-tert-butyl-6-methylphenyl)-2-pyridine Aimine, N-(2,4-dibenzyl-6-methylphenyl)-2-pyridinemethimine;

N-(2,6-dimethylphenyl)-2-pyridineethylimine, N-(2,6-diethylphenyl)-2-pyridineethylimine, N-(2,6-di Isopropylphenyl)-2-pyridineethylimine, N-(2,6-diisobutylphenyl)-2-pyridineethylimine, N-(2,6-di-tert-butylphenyl) -2-pyridineethylimine, N-(2,6-dibenzylphenyl)-2-pyridineethylimine, N-(2,4-dimethylphenyl)-2-pyridineethylimine, N-(2,4-diethylphenyl)-2-pyridineethylimine, N-(2,4-diisopropylphenyl)-2-pyridineethylimine, N-(2,4- Diisobutylphenyl)-2-pyridineethylimine, N-(2,4-di-tert-butylphenyl)-2-pyridineethylimine, N-(2,4-dibenzylphenyl) -2-pyridineethylimine;

N-(2,4,6-trimethylphenyl)-2-pyridineethylimine, N-(2,4,6-triethylphenyl)-2-pyridineethylimine, N-(2 , 4,6-triisopropylphenyl)-2-pyridineethylimine, N-(2,4,6-triisobutylphenyl)-2-pyridineethylimine, N-(2,4 , 6-tri-tert-butylphenyl)-2-pyridineethylimine.

The n in the catalyst carrier MgCl ₂ n(ROH) of the present invention is preferably 0.1-1.0, and the ROH is preferably a C ₂ -C ₆ fatty alcohol, such as ethanol, propanol, isopropanol, n-butanol, isobutanol or Hexanol.

The preparation method of described catalyst comprises:

(1) preparing a suspension of the carrier MgCl ₂ ·n(ROH) in an inert hydrocarbon solvent, wherein n in the carrier is 0.1-2.0, and R is an alkyl group of C ₂ -C ₈ ;

(2) Add pyridine-2-alkylimine titanium tetrachloride shown in formula (I) into an organic solvent to make a solution, then add TiCl ₄ to make TiCl ₄ and pyridine-2 shown in formula (I) - the mol ratio of alkylimine titanium tetrachloride is 0.1～5.0: 1,

(3) Add the solution prepared in step (2) to the suspension prepared in step (1), stir fully at 0-150°C to make the carrier and active component fully contact and react, then wash with an inert hydrocarbon solvent and dry .

In the method, the carrier used in step (1) is prepared by two different methods. One is prepared by de-alcoholizing the adduct of magnesium chloride alcohol, that is, anhydrous magnesium chloride is completely dissolved with a sufficient amount of alcohol, and the adduct of MgCl ₂ (ROH) is obtained after drying, and then added Dealcoholization of the compound by heating or dehydration of the alcohol with an organic compound such as aluminum alkyl to obtain an activated support. When using this type of carrier to load the active ingredient, it is necessary to dissolve the carrier in a suspension in an inert hydrocarbon solvent, and then load the active ingredient.

When n in the carrier MgCl ₂ ·n(ROH) is 0.1-1.0, the magnesium chloride can be activated by direct alcoholization. The activation method is: suspend anhydrous _MgCl2 in an inert hydrocarbon solvent, first add a dispersant at 30-200°C to pre-disperse anhydrous magnesium chloride, and then add _C2 - _C8 alcohol to activate, in which the dispersant and The molar ratio of anhydrous magnesium chloride is 0.01-2.0, and the dispersant is selected from alkoxytitanium compounds with the general formula Ti(OR') ₄ or C ₃ -C ₈ alcohols, wherein R' is C ₂ -C ₆ alkanes base. The dispersant is preferably titanium ethoxide, titanium propoxide or titanium butoxide. For the detailed preparation method, refer to CN1264713A. Since the activated carrier prepared by the above method does not need dealcoholization, the inert hydrocarbon suspension formed during its preparation can be directly used to load the active component.

The step (2) in the method of the present invention is to prepare the active component solution for loading, and the organic solvent used in the preparation should be able to dissolve the active component, so as to facilitate the uniform distribution of the active center on the carrier. The amount of solvent used is 5-150 times, preferably 10-50 times of the total amount of active components. The preferred organic solvent is C ₁ -C ₄ halogenated alkanes, benzene, toluene or xylene, preferably C ₁ -C ₄ chlorinated alkanes or toluene, more preferably dichloromethane or dichloroethane. The temperature for dissolving the active component with an organic solvent is preferably 30-100°C, and the dissolving time is preferably 0.1-1.5 hours.

The step (3) of the method is the loading of the active component, the loading temperature is preferably 30-100° C., and the time is preferably 0.5-12 hours. Appropriately increasing the loading time is conducive to fully loading the active component on the carrier, and avoiding the catalyst in the The active center is detached during the polymerization process. After loading, the solvent is removed, and the obtained solid is washed with an inert hydrocarbon to remove components that are not firmly loaded, and the catalyst is obtained after drying.

The inert hydrocarbon solvent used for loading or washing in the preparation method is selected from C ₅ -C ₁₅ alkanes or C ₆ -C ₈ aromatics, preferably C ₅ -C ₁₂ alkanes, most preferably hexane, heptane, Octane and Decane.

The preparation method of the active component pyridine-2-alkylimine titanium tetrachloride of the present invention is: the adduct and pyridine-2-alkylimine made after dissolving TiCl ₄ or TiCl ₄ in an ether solvent The amine derivative is reacted in an organic solvent in an equimolar ratio, and after the reaction is completed, the solid is collected and dried to obtain the catalyst. The organic solvent is selected from C ₁ -C ₄ chlorinated alkanes, C ₁ -C ₄ alcohols or C ₆ -C ₁₂ aromatic compounds, preferably dichloromethane, dichloroethane, toluene or xylene. For the detailed preparation method, refer to CN1331252A.

The catalyst described in the present invention is suitable for the polymerization or copolymerization of α-olefins, and the α-olefins are preferably C ₂ -C ₈ olefins. During the polymerization, the catalyst described in the present invention is used as the main catalyst, and alkylaluminoxane, alkylaluminum, alkylaluminum halide or any mixture of two or more thereof is used as a co-catalyst to make α-olefins polymerize react under conditions. During the reaction, the molar ratio of Al/Ti is 20-2000, preferably 25-1000. The polymerization temperature is 10-110° C., preferably 20-100° C., and the polymerization pressure is 0.1-8.0 MPa, preferably 0.1-1.0 MPa.

Among the cocatalysts, the alkylaluminoxane is preferably methylaluminoxane, the alkylaluminum is preferably triethylaluminum and triisobutylaluminum, and the alkylaluminum halide is preferably monochlorodiethylaluminum. The cocatalyst can also be a mixture of any two or more of methylaluminoxane, triethylaluminum, triisobutylaluminum and diethylaluminum chloride. The α-olefin is preferably ethylene, propylene or butene, and the comonomer is preferably butene, hexene or octene.

Slurry polymerization can be adopted when carrying out olefin polymerization with the catalyst of the present invention, and the solvent during polymerization can be selected alkanes, aromatic hydrocarbons and halogenated alkanes, and the preferred solvent is linear alkanes, such as n-butane, n-hexane and n-heptane, Or branched alkanes, such as isobutane, isopentane, isooctane. In addition, the catalyst of the present invention is also suitable for gas phase bulk polymerization, such as gas phase fluidized bed polymerization.

The present invention will be described in detail below by examples, but the present invention is not limited thereto.

The melting point and crystallinity of the polymers in the examples were determined by differential scanning calorimetry (DSC). The measuring instrument is TA5000DSC2910 thermal analyzer. Test conditions: under N ₂ atmosphere, the heating rate is 10°C/min, and the heating range is 40-300°C. The degree of crystallinity is calculated according to the following formula:

X% = ΔH _f / ΔH _f0 × 100%

ΔH _f is the heat of fusion of polyethylene measured by DSC,

ΔH _f0 is the heat of fusion of crystalline polyethylene, and its value is 291.7 J/g.

The molecular weight and molecular weight distribution of the polymer were determined by gel permeation chromatography (GPC), and the instrument used was an Alliance GPC2000 gel permeation chromatograph from Waters, USA.

Example 1

Preparation of N-(2,6-diisopropylphenyl)-2-pyridinemethanimine titanium tetrachloride [(iPr ₂ Ph)PyH]TiCl ₄ .

(1) Preparation of N-(2,6-diisopropylphenyl)pyridine-2-methanimine (iPr ₂ Ph)PyH

Dissolve 10 mmol of 2,6-diisopropylaniline (Sweden, Acrs Company) in 20 ml of methanol, add 10 mmol of 2-pyridinecarbaldehyde (Sweden, Acrs Company), and then add 5 drops of formic acid. Heated to 65°C and refluxed for 3 hours, cooled to room temperature, removed the solvent under reduced pressure, cooled the resulting solid to -50°C, washed twice with 10ml-30°C ethanol, and dried in vacuo at 30°C to obtain 1.8 g of N-( The yield of 2,6-diisopropylphenyl)pyridine-2-methanimine [(iPr ₂ Ph)PyH] was 68% by mass.

(2) Preparation of [(iPr ₂ Ph)PyH]TiCl ₄

Under ice bathing and stirring, 4.5 mmol of tetrahydrofuran was added dropwise into 20 ml of toluene solution containing 2.1 mmol of titanium tetrachloride, reacted at room temperature for 4 hours, filtered, and vacuum-dried at 30°C for 2 hours to obtain 0.68 g of yellow solid TiCl ₄ 2THF. The yield was 97% by mass.

Add 2.1mmol of TiCl ₄ 2THF to 20ml of dichloromethane, stir to dissolve, then add 10ml of dichloromethane solution containing 2.1mmol (iPr ₂ Ph)PyH, reflux at 25°C for 18 hours, cool, filter, and separate the solids Wash twice with 10 ml of diethyl ether, and dry in vacuum at 30°C for 2 hours to obtain 0.72 g of yellow-green solid complex a: [(iPr ₂ Ph)PyH]TiCl ₄ , the structural formula is as follows, and the yield is 75% by mass.

Example 2

Prepare N-(2,4,6-trimethylphenyl)-2-pyridyl imine titanium tetrachloride by the method of example 1, the difference is to replace with 10mmol of 2,4,6-trimethylaniline 2,6-Diisopropylaniline was reacted to obtain titanium complex b having the following structure with a yield of 60% by mass.

Example 3

Prepare N-(2,6-diisopropylphenyl)-2-pyridine ethylimide titanium tetrachloride according to the method of example 1, the difference is that (1) step is carried out with 2-acetylpyridine instead of 2-formaldehyde pyridine Reaction, the titanium complex c having the following structural formula was obtained, and the yield was 72% by mass.

Example 4

Preparation of the catalyst of the present invention.

(1) Preparation of activated carrier

Take 1.46g (15mmol) of anhydrous magnesium chloride powder, put it into a three-neck flask with reflux condenser and stirring, add 40ml of hexane under nitrogen protection, stir and heat up to 70°C to make a suspension, add 0.12ml (0.35 mmol) of butoxytitanium [Ti(OBu) ₄ ], the magnesium chloride powder was fully dispersed in hexane, continued to stir and reacted at 70°C for 1 hour, slowly added 0.40ml (5.4mmol) of n-butanol dropwise, continued React at this temperature for 1 hour to obtain a hexane suspension of activated carrier MgCl ₂ ·0.36(BuOH).

(2) load active components

Take 1.03g (2.26mmol) of the complex a prepared in Example 1 and add it to a 50ml small glass bottle with stirring, replace it with nitrogen, remove the water and air in the system, add 10ml CH ₂ Cl ₂ , stir to dissolve the complex a , dropwise into 0.5ml (4.56mmol) TiCl ₄ solution, stirred at 50°C for 0.5 hour to dissolve it to obtain a solution containing the active component.

Add the above-mentioned solution containing active components dropwise to the activated carrier hexane suspension prepared in step (1), stir and react at 60°C for 2 hours, stop stirring, let stand until the reaction liquid is separated, remove the supernatant, and then The precipitate was washed three times with 90 ml of hexane until the washing solution was completely colorless, and dried under reduced pressure to obtain a solid catalyst A with good fluidity, wherein the content of titanium was 6.85% by mass and the content of magnesium was 10.7% by mass.

Example 5

Catalyst B was prepared according to the method of Example 4, except that the addition of _TiCl4 solution was 0.10ml (0.92mmol). Catalyst B had a titanium content of 4.51% by mass and a magnesium content of 11.5% by mass.

Example 6

Catalyst C was prepared in the same manner as in Example 4, except that the amount of TiCl solution added was 0.25ml (2.26mmol) _. Catalyst C had a titanium content of 4.83% by mass and a magnesium content of 11.0% by mass.

Example 7

Catalyst D was prepared according to the method of Example 4, except that the added complex was b, the addition amount was 0.95g (2.26mmol), and the addition amount of _TiCl4 solution was 0.25ml (2.26mmol). Catalyst D had a titanium content of 4.97% by mass and a magnesium content of 11.2% by mass.

Example 8

Catalyst E was prepared according to the method of Example 4, except that the added complex was c, the addition amount was 1.06g (2.26mmol), and the addition amount of _TiCl4 solution was 0.25ml (2.26mmol). Catalyst E had a titanium content of 4.61% by mass and a magnesium content of 10.8% by mass.

Example 9

(1) Preparation of activated carrier

Take 1.46g (15mmol) of anhydrous magnesium chloride powder, put it into a three-neck flask with reflux condenser and stirring, add 40ml of hexane under nitrogen protection, stir and heat up to reflux temperature to make a suspension, add 4.74g n-butanol (60 mmol), stirred to completely dissolve the magnesium chloride, the solvent was removed under reduced pressure, and the solid was dealcoholized by heating at 150°C to obtain the carrier MgCl ₂ ·1.5(BuOH).

(2) load active components

Add 1.8 g of carrier MgCl ₂ ·1.5 (BuOH) into 40 ml of hexane to make a suspension. Then take 1.03g (2.26mmol) of complex a prepared in Example 1 and add 10ml CH ₂ Cl ₂ , stir to dissolve it, then drop into 0.5ml (4.56mmol) TiCl ₄ solution, stir at 50°C for 0.5 hours to obtain The solution. Add this solution dropwise to the above-prepared carrier suspension, stir and react at 60°C for 2 hours, let stand until the reaction solution is separated, remove the supernatant, and then wash the precipitate three times with 90ml hexane until the washing solution is complete. It was colorless and dried under reduced pressure to obtain solid catalyst F with good fluidity, wherein the titanium content was 4.87% by mass and the magnesium content was 6.0% by mass.

Comparative example 1

Catalyst M was prepared according to the method of Example 4, except that the supported active component was TiCl ₄ , and the obtained catalyst M had a titanium content of 6.41% by mass and a magnesium content of 13.2% by mass.

Comparative example 2

Catalyst N is prepared according to the method of example 4, and the difference is that the active component of loading is N-(2,6-diisopropylphenyl)-2-pyridinemethanimine titanium tetrachloride, and the catalyst N titanium content that obtains 2.29% by mass and 19.4% by mass of magnesium

Instances 10-17

The following examples carry out high pressure ethylene polymerization.

The 1-liter autoclave was replaced three times with nitrogen, and then replaced with ethylene once, then 300ml of dry hexane, 11ml of triethylaluminum in hexane and 38mg of solid catalyst were added successively, the temperature was raised to 70°C, and then ethylene was introduced The pressure was increased to 0.8MPa, and the polymerization reaction was carried out for 0.5 hours. Catalyst used in each example, catalyst activity and polymer properties are shown in Table 1.

Instances 18-20

Carry out ethylene polymerization reaction by the method for example 10, difference is to pass into hydrogen before passing into ethylene, keep certain hydrogen partial pressure during the polymerization process, and total pressure still maintains as 0.8MPa. The catalysts used in each example, the partial pressure of hydrogen and the properties of the obtained polymers are shown in Table 2, wherein the DSC spectrum and GPC spectrum of the polyethylene product prepared using catalyst C are shown in Figure 1 and Figure 2, respectively.

Instances 21~22

The ethylene copolymerization reaction is carried out with the catalyst of the present invention.

Carry out polymerization reaction by the method for example 10, difference is that 10ml 1-hexene is added during reaction, and feeds hydrogen in reactor, makes hydrogen partial pressure be 0.1MPa, polymerization reaction 0.5 hour under 70 ℃, catalyst activity and polymerization The physical properties are shown in Table 2.

Example 23

The polymerization reaction was carried out according to the method of Example 10, except that 18 ml of a toluene solution of methylaluminoxane with a concentration of 10% by mass was added as a cocatalyst. The catalyst activity and polymer properties are shown in Table 2.

Example 24

Carry out ethylene polymerization with catalyst A according to the method of Example 10, except that the polymerization temperature is 50° C., and the pressure of feeding ethylene is 0.1 MPa. The catalyst activity is 2.32×10 ⁵ gPE·(molTi·hr) ^-1 .

Table 1 instance number Catalyst number Catalytic activity, 10 ⁶ gPE·(molTi·hr) ^-1 Melting point, °C Crystallinity, % M _w , (×10 ⁴ ) M _w /M _n 10 A 3.30 133.9 78.3 49.0 59.56 11 B 3.18 132.64 79.4 31.4 39.50 12 C 3.10 133.9 79.1 125.7 34.53 13 D. 0.75 133.7 68.3 76.3 103.60 14 E. 2.48 130.7 73.5 48.9 12.98 15 f 0.84 130.02 65.2 65.3 9.72 16 m 2.16 133.2 73 65.9 7.73 17 N 1.10 134.2 69.0 94.1 7.15

Table 2 instance number Catalyst number Hydrogen partial pressure, MPa Catalytic activity, 10 ⁶ gPE·(molTi·hr) ^-1 Melting point, °C Crystallinity, % M _w , (×10 ⁴ ) M _w /M _n 18 A 0.2 2.91 133.77 87.1 6.8 15.20 19 B 0.1 2.51 133.65 81.0 14.0 21.84 20 C 0.1 2.45 133.92 78.5 17.2 28.18 twenty one A 0.1 2.34 129.81 68.5 10.2 15.82 twenty two B 0.1 1.32 130.77 73.5 12.7 12.98 twenty three A - 1.61 132.16 74.8 39.3 10.50

Claims (12)

1, a kind of dual-active component polyolefin catalyst comprises carrier MgCl ₂N (ROH), TiCl ₄And the pyridine shown in the formula (I)-2-alkyl imines titanium tetrachloride,

R in the formula (I) ₁, R ₂Be respectively single substituting group or multi-substituent on pyridine ring and the aniline ring, be selected from hydrogen, C independently of one another ₁～C ₆Alkyl or C ₇～C ₈Aralkyl, carrier MgCl ₂N is 0.1～2.0 among the n (ROH), and R is C ₂～C ₈Alkyl; Titanium content is 0.5～12 quality % in the described catalyzer, and Mg content is 5～20 quality %, TiCl ₄With the mol ratio of pyridine-2-alkyl imines titanium tetrachloride be 0.1～5.0: 1.

2, according to the described catalyzer of claim 1, it is characterized in that R ₁And R ₂Be selected from hydrogen or C respectively ₁～C ₄Alkyl, R ₃Be hydrogen, methyl or ethyl, TiCl in the catalyzer ₄With the mol ratio of pyridine-2-alkyl imines titanium tetrachloride be 0.4～3.0: 1.

3,, it is characterized in that described carrier MgCl according to the described catalyzer of claim 1 ₂N is 0.1～1.0 among the n (ROH), and described ROH is selected from ethanol, propyl alcohol, Virahol, propyl carbinol, isopropylcarbinol or hexanol, and titanium content is 2.0～5.0 quality % in the catalyzer, and Mg content is 5～13 quality %.

4, the described Preparation of catalysts method of a kind of claim 1 comprises:

(1) preparation carrier MgCl ₂The suspension of n (ROH) in unreactive hydrocarbons solvent, n is 0.1～2.0 in the carrier, R is C ₂～C ₈Alkyl;

(2) with making solution in the pyridine shown in the formula (I)-2-alkyl imines titanium tetrachloride adding organic solvent, add TiCl again ₄, make TiCl ₄With the mol ratio of the pyridine shown in the formula (I)-2-alkyl imines titanium tetrachloride be 0.1～5.0: 1,

(3) solution made of (2) step is joined in the suspension that (1) step makes, fully stirs in 0～150 ℃ and make carrier and the abundant contact reacts of active ingredient, then with unreactive hydrocarbons solvent wash, drying.

5, in accordance with the method for claim 4, it is characterized in that (1) step preparation carrier MgCl ₂The method of n (ROH) suspension is with anhydrous MgCl ₂Be suspended in the unreactive hydrocarbons solvent, elder generation carries out Magnesium Chloride Anhydrous at 30～200 ℃ of adding dispersion agents pre-dispersed, and then adds C ₂～C ₈Alcohol activate, wherein the mol ratio of dispersion agent and Magnesium Chloride Anhydrous is 0.01～2.0, it is Ti (OR ') that dispersion agent is selected from general formula ₄Alkoxy titanium compound or C ₃～C ₈Alcohol, wherein R ' is C ₂～C ₆Alkyl, n is 0.1～1.0 in the described carrier, ROH is selected from ethanol, propyl alcohol, Virahol, propyl carbinol, isopropylcarbinol or hexanol.

6, in accordance with the method for claim 5, it is characterized in that described dispersion agent is selected from ethanolato-titanium, titanium propanolate or titanium butoxide.

7,, it is characterized in that described unreactive hydrocarbons solvent is selected from C according to claim 4 or 5 described methods ₅～C ₁₅Alkane or C ₆～C ₈Aromatic hydrocarbons.

8, in accordance with the method for claim 4, it is characterized in that (1) described carrier is made through hot dealcoholysis by the adducts of magnesium chloride alcohol.

9, in accordance with the method for claim 4, it is characterized in that described organic solvent of (2) step is selected from C ₁～C ₄Chloroparaffin, benzene, toluene or dimethylbenzene.

10, in accordance with the method for claim 4, it is characterized in that the temperature that carrier contacts with active ingredient in (3) step is 30～100 ℃, the reaction times is 0.5～12 hour.

11, the method for a kind of alpha-olefine polymerizing or copolymerization, comprise that with the described catalyzer of claim 1 be Primary Catalysts, with alkylaluminoxane, aluminum alkyls, alkyl aluminum halide or any two or more the mixture in them is promotor, alpha-olefin is reacted under polymerizing condition, and the Al/Ti mol ratio is 25～1000 during reaction.

12, according to the described polymerization process of claim 11, it is characterized in that described alkylaluminoxane is a methylaluminoxane, aluminum alkyls is triethyl aluminum, triisobutyl aluminium, alkyl aluminum halide is an aluminium diethyl monochloride, alpha-olefin is ethene, propylene or butylene, and comonomer is selected from butylene, hexene or octene.

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