CN1931885B - Catalyst for olefin polymerization and preparation method thereof - Google Patents

Abstract

The present invention relates to catalyst for polymerization and copolymerization of olefin and its preparation process. The catalyst is obtained through dissolving magnesium halide in homogeneous solution of organic epoxy compound, organophosphorus compound and electron donor compound, and the reaction with the mixture solution of titanium halide or its derivative and liquid co-precipitant. Using the liquid co-precipitant intersoluble with titanium compound can omit the step of dissolving separating assistant, is favorable to the depositing separation of catalyst mother liquid system, raises the yield of the catalyst, avoids the residue of co-precipitant in catalyst product and raises the quality of polymer. The catalyst for polymerization and copolymerization of olefin has high activity and results in good polymer state.

Description

Catalyst for olefin polymerization and preparation method thereof

Field of invention:

The present invention relates to a catalyst for olefin polymerization or copolymerization and its preparation method.

Background of the invention:

Since the 1970s, Japan's Mitsui Petrochemical Industry Co., Ltd. and other companies have successfully developed a variety of Ti-Mg high-efficiency carrier catalysts with magnesium chloride as the carrier, which has enabled the rapid development of the world's slurry production of polyolefin industry. A more representative technology is the method of ethylene polymerization and copolymerization disclosed by Mitsui Oil & Chemical in Japanese Patent JP49-51378. The specific preparation method of the catalyst is: the reaction of magnesium dichloride and ethanol after grinding and pulverizing in a lamp oil medium to form MgCl ₂ 6C ₂ H ₅ OH alcoholate slurry, and then undergo esterification reaction with diethylaluminum chloride to remove most of the ethanol, and finally use titanium tetrachloride for titanium loading reaction to obtain Ti/MgCl ₂ high-efficiency carrier catalyst . The preparation process of the catalyst is simple, the reaction conditions are not harsh, the operation is easy, and the catalyst has high activity when used for ethylene polymerization or copolymerization. However, in the whole catalyst preparation process, since the catalyst uses alcohols and alkane solvents with large differences in polarity to dissolve magnesium halide, this is a very difficult process, because in this case, even if heated to a relatively high If the temperature is above 100°C, for example, the magnesium halide cannot be completely dissolved to form a homogeneous solution, but only a fine colloidal suspension or a swollen magnesium halide slurry is produced. This brings some shortcomings related to the layered crystallization characteristics of magnesium halide to the prepared catalyst. The carrier magnesium chloride basically retains the irregular sheet form formed during the original grinding and pulverization in the slurry reaction system, resulting in the final obtained Ti/MgCl ₂ The particle shape of the solid catalyst is poor, the thickness is uneven, and there are many fine powders. In order to ensure that a catalyst with better performance is obtained, the specification of this patent particularly emphasizes that the amount of alcohol used in the alcoholation reaction is at least four moles per mole of magnesium chloride, especially six moles. Therefore, the amount of aluminum alkyl and titanium tetrachloride Both are larger. If the amount of alcohol is less, the obtained catalyst will have lower activity when used in ethylene polymerization, poor particle shape, and uneven particle size distribution. Due to the poor particle shape of the polymer, the slurry concentration during slurry polymerization is low, which directly affects Improve the production efficiency of production equipment.

Chinese patent 8510097.2 discloses a catalyst system for olefin homopolymerization and copolymerization, the catalyst system comprising: (a) Ti-containing solid catalyst component, (b) alkylaluminum compound, (c) organosilicon, wherein (A) Component is a homogeneous solution formed by dissolving magnesium halide in organic epoxy compounds and organic phosphorus compounds. The solution is mixed with titanium tetrahalide or its derivatives, and the precipitation aids such as organic anhydrides, organic acids, ethers, ketones, etc. In the presence of the compound, a solid is precipitated; the solid is treated with a polycarboxylic acid ester to attach it to the solid, and then treated with titanium tetrahalide and an inert diluent. The catalyst adopts a mixed solvent system composed of chlorine-containing epoxides, organic phosphorus compounds and toluene to replace alcohols and alkane solvent systems to dissolve magnesium halide. Due to the similar polarity of these components. Therefore, the magnesium halide can be completely dissolved at a relatively low temperature, such as 50° C., to form a homogeneous solution. This leads to improvements in catalysts associated with the lamellar crystalline character of magnesium halides. Especially in terms of apparent density, regularity and particle shape, the improvement is obvious. However, when the catalyst system is used for propylene polymerization, the catalyst activity is high, the isotacticity of the obtained polymer is high, and the apparent density is also high. When used for ethylene polymerization, the catalyst activity is relatively low. For example, under the conditions of 85° C., hydrogen pressure of 0.25 MPa, and ethylene pressure of 0.75 MPa disclosed in Example 24, ethylene was polymerized for 2 hours, and the polymerization activity was 537 Kg polyethylene/ gTi (10.7kgPE/gcat), and the hydrogen adjustment is not sensitive enough.

Chinese patent 98101108.X proposes a catalyst for homopolymerization or copolymerization of ethylene and a preparation method of the catalyst, wherein the catalyst is dissolved in an organic epoxy compound and an organic phosphorus compound by magnesium halide and then added to an electron donor to form a uniform solution , obtained by reacting with at least one precipitation aid and transition metal titanium halide or its derivatives, and combined with organoaluminum compounds during polymerization. The catalyst has a simple preparation process and shows high activity for ethylene polymerization, and at the same time The particle shape of the obtained polymer is better, the apparent density is higher, and the content of low molecular matter is less.

Although the catalyst systems of the above two patents have good performance for olefin polymerization, the former is more inclined to propylene polymerization, and the latter is more inclined to ethylene polymerization, but in order to obtain catalyst solids in the preparation process of the above two catalyst systems, both The method of adding a precipitation aid is adopted. The more effective precipitation aid is one of organic acid anhydrides, organic acids, ethers, and ketones. Especially when phthalic anhydride is used as a precipitation aid, the effect is better. The method is Phthalic anhydride must be completely dissolved in the mixed solvent system first, and then cooled and mixed with the titanium compound. During the mixing process, the catalyst solid grows from scratch in the mother liquor system and gradually aggregates and grows. In order to obtain a good catalyst particle shape, therefore The mixing speed and reaction temperature of the system need to be strictly controlled, and generally a longer heating time is required, so the use of such precipitation aids prolongs the preparation period of the catalyst accordingly. In addition, the above-mentioned precipitation aid system is relatively more toxic, has higher requirements on operating conditions, and is also more costly.

Invention content:

In view of the shortcomings of the above catalyst system, the present invention preferably uses a specific inert solvent that is miscible with the titanium compound used as a co-precipitant to successfully prepare a new type of titanium-based polyolefin catalyst. The catalyst prepared by this method has properties equivalent to or better than the above-mentioned patent catalyst. Good performance, and omits the dissolution reaction step of the precipitation aid, and the method also has the following advantages: firstly, the addition of this type of coprecipitant is beneficial to the sedimentation and separation of the catalyst mother liquor system, and secondly, the method can improve the catalyst yield , Finally, this type of co-precipitant does not remain in the finished catalyst, which helps to reduce the ash content of the polymerization product, thereby improving the quality of the resin.

The present invention is used for the catalyst of olefin polymerization or copolymerization, comprises following component:

A. The titanium-containing solid catalyst component is formed by dissolving magnesium halide in organic epoxy compounds and organic phosphorus compounds and then adding electron donors to form a uniform solution, and then co-precipitating with liquid and transition metal titanium halides or their derivatives obtained by the action of a mixture solution, wherein the electron donor is selected from one of organic alcohols and organic ethers or a mixture thereof;

B. An organoaluminum compound, the general formula of which is AlR _n X _3-n , where R is hydrogen, a hydrocarbon group with 1 to 20 carbon atoms, X is a halogen, and n is an integer of 0<n≤3;

The ratio between component B and component A is 5-1000 in terms of molar ratio of aluminum to titanium.

The magnesium halide described in the catalyst component A of the present invention is magnesium dihalide, the complex of water and alcohol of magnesium dihalide, and in the derivative of magnesium dihalide molecular formula wherein one halogen atom is replaced by hydrocarbyl or hydrocarbyloxy one, or a mixture of them. The above-mentioned magnesium dihalides are specifically: magnesium dichloride, magnesium dibromide, magnesium diiodide, preferably magnesium dichloride.

The organic epoxy compound described in the catalyst component A of the present invention is selected from the oxides, glycidyl ethers and inner ethers of aliphatic olefins, diolefins or halogenated aliphatic olefins or diolefins with 2 to 8 carbon atoms and other compounds. Specifically, such as: ethylene oxide, propylene oxide, butylene oxide, butadiene oxide, butadiene double oxide, epichlorohydrin, methyl glycidyl ether, diglycidyl ether, tetrahydrofuran, etc. Among them, ethylene oxide, propylene oxide, epichlorohydrin, and tetrahydrofuran are preferred, and tetrahydrofuran and epichlorohydrin are the best.

Organophosphorus compounds include hydrocarbyl or halogenated hydrocarbyl esters of orthophosphoric acid or phosphorous acid. Specific examples: trimethyl orthophosphate, triethyl orthophosphate, tributyl orthophosphate, triphenyl phosphite, trimethyl phosphite, triethyl phosphite, tributyl phosphite, triphenyl phosphite , Benzyl phosphite, etc. Among them, trimethyl orthophosphate, triethyl orthophosphate and tributyl orthophosphate are preferred, and tributyl orthophosphate is the best.

The organic alcohol in the electron donor described in the catalyst component A of the present invention includes _C1 ～ _C12 straight chain alcohol or isomeric alcohol, for example: methanol, ethanol, propanol, isopropanol, butanol, isobutanol Alcohol, 2-ethylhexanol, n-octanol, dodecyl alcohol, glycerol, ethanol, butanol, 2-ethylhexanol, glycerol are the best; the organic Ether is a lower aliphatic ether, such as: methyl ether, diethyl ether, propyl ether, butyl ether, pentyl ether, diethyl ether, etc.

During the process of dissolving the magnesium halide described in the catalyst component A of the present invention to form a homogeneous solution, a metal halide regulator can also be added, wherein the metal halide is selected from one or more of the halides of zinc, vanadium, iron, and cobalt. their mixture. The effect of adding the metal halide is to make the effect of using hydrogen to regulate the molecular weight of the polymer more obvious when the catalyst is used in the ethylene polymerization process.

In the process of dissolving the magnesium halide described in catalyst component A of the present invention to form a homogeneous solution, metal alkyl compounds such as zinc alkyl and/or aluminum alkyl can also be added, wherein triethylaluminum, triisobutyl Aluminum and Diethylzinc.

The selection principle of the liquid co-precipitating agent described in the catalyst component A of the present invention is that it is a precipitating agent for the magnesium halide solution system when used alone within a selected temperature range. The liquid coprecipitant described in the catalyst component A of the present invention is _C1 ～ _C10 aliphatic hydrocarbon, alicyclic hydrocarbon or their mixture, preferably hexane, heptane, octane, decane and cyclohexane, Heptane and decane are the best.

Inert diluents such as benzene, toluene, xylene, 1,2-dichloroethane, chlorobenzene and other hydrocarbons or halogenated hydrocarbons can also be added appropriately when the magnesium halides described in the catalyst component A of the present invention are dissolved. Compound, wherein preferred benzene, toluene, xylene, with toluene, xylene being the best.

The halide of the transition metal Ti or its derivatives described in the catalyst component A of the present invention has the general formula TiX _n (OR) _4-n , wherein X is a halogen, and R is an aliphatic hydrocarbon group of C ₁ to C ₁₄ or Aromatic hydrocarbon group, n is an integer from 0 to 4, such as titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, tetrabutoxytitanium, tetraethoxytitanium, chlorotriethoxytitanium, dichloro One of diethoxytitanium, trichloromonoethoxytitanium or their mixture, preferably titanium tetrachloride.

When the catalyst component A of the present invention is used for propylene polymerization, it is necessary to add polycarboxylic acid ester before or after the precipitation of solids. Described polycarboxylic acid ester comprises aliphatic polycarboxylic acid ester and aromatic polycarboxylic acid ester, specifically as: diethyl malonate, dibutyl malonate, diethyl adipate, adipate diethyl Butyl ester, diethyl sebacate, dibutyl sebacate, di-n-butyl phthalate, diisobutyl phthalate, diisooctyl phthalate, di-maleic acid Ethyl ester, di-n-butyl maleate, diethyl naphthalene dicarboxylate, dibutyl naphthalene dicarboxylate, triethyl trimellitate, tributyl pyromellitate, tetramellitic acid ethyl ester, etc., preferably di-n-butyl phthalate, diisobutyl phthalate, and di-isooctyl phthalate.

The molar ratio between the various components described in the catalyst component A of the present invention is based on each mole of magnesium halide, the organic epoxy compound is 0.01 to 10 moles, preferably 0.02 to 4 moles; the organic phosphorus compound is 0.01 to 10 moles, preferably 0.01 to 10 moles 0.02 to 4 moles is better; electron donor is 0.005 to 15 moles, preferably 0.05 to 10 moles; metal halide is 0 to 0.2 moles, preferably 0 to 0.08 moles; alkyl metal compound is 0 to 2 moles, preferably 0 ～0.5 mole is good; transition metal Ti halide 0.2～20 mole, multi-carboxylate 0～2 mole, the volume ratio of liquid coprecipitant and Ti halide is 0.1～10, preferably 0.5～2.5.

Component B is an organoaluminum compound, its general formula is AlR _n X _3-n , where R is hydrogen, a hydrocarbon group with 1 to 20 carbon atoms, especially an alkyl group, an aralkyl group, an aryl group, etc.; X is Halogen, especially chlorine and bromine; n is an integer of 0<n≤3. Specific compounds such as: trimethylaluminum, triethylaluminum, triisobutylaluminum, trioctylaluminum and other trialkylaluminums; monohydrogen diethylaluminum, monohydrogen diisobutylaluminum and other alkylaluminum hydrides; Alkyl aluminum chlorides such as diethylaluminum monochloride, diisobutylaluminum monochloride, sesquiethylaluminum chloride, ethylaluminum dichloride, etc. Among them, triethylaluminum and triisobutylaluminum are preferred.

The molar ratio of aluminum in component B of the catalyst system of the present invention to titanium in component A is 5-1000, preferably 20-800.

When the catalyst system of the present invention is used for propylene polymerization, it is also necessary to add an external electron donor, whose general formula is an organosilane of R _n Si(OR') _4-n , and R and R' are the same or different hydrocarbon groups , halogenated hydrocarbon group, where 0≤n≤3. Specifically, such as: trimethylmethoxysilane, trimethylethoxysilane, trimethylphenoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethylsilane Oxysilane, diphenyldiethoxysilane, monophenyltrimethoxysilane, monophenyltriethoxysilane, dicyclohexyldimethoxysilane, dicyclohexyldiethoxysilane, etc.

The molar ratio of aluminum in component B of the catalyst system of the present invention to silicon in the external electron donor is 50-0.5.

The preparation method of component A in the catalyst of the present invention is as follows: under stirring, magnesium halide is dissolved in organic epoxy compound and organic phosphorus compound, and then electron donor is added, and metal halide and/or alkyl metal compound can also be added to form Uniform and transparent solution, at a temperature of -35 to 60°C, preferably -30 to 10°C, drop the mixture solution of titanium compound and liquid coprecipitant into the uniform solution of magnesium halide or drop the magnesium halide solution into the titanium compound and liquid In the mixture solution of the coprecipitant, when the method of adding titanium halide dropwise is adopted, the dropping time is preferably controlled within 5 hours. When the temperature is gradually raised, the heating rate is preferably 4-100 ° C per hour; and then the reaction Stir the mixture for 1 minute to 10 hours at a temperature of 0-130°C, preferably 20-130°C, stop stirring, settle, filter, remove the mother liquor, and wash the solids with toluene and hexane. A titanium-containing solid catalyst component is produced. When the catalyst component A of the present invention is used for propylene polymerization, polycarboxylate should be added before or after solid precipitation.

When component B is used for washing, the amount of component B is 100-0.001, preferably 10-0.01, most preferably 1-0.1, based on the molar ratio of aluminum to titanium.

The solid component A obtained in the present invention is a powdery solid particle with an average particle size of about 2-100 microns, and the particle size can be controlled by changing the preparation conditions. The specific surface area is generally above 100 ^m2 /g.

Through the above steps, the A component of the catalyst system of the present invention is obtained, which can be used in the form of solid or suspension. The catalyst A and B components of the present invention can be directly applied to the polymerization system, and can also be pre-complexed Then applied to the polymerization system.

The catalyst of the present invention can be used for the homopolymerization of ethylene, and can also be used for the copolymerization of ethylene and α-olefin. The comonomers can be propylene, butene, pentene, hexene, octene, 4-methyl-1-pentene ; Can also be used for homopolymerization and copolymerization of propylene.

During polymerization, either liquid phase polymerization or gas phase polymerization can be used. For liquid phase polymerization, propane, hexane, heptane, cyclohexane, isobutane, isopentane, naphtha, raffinate, hydrogenated gasoline, kerosene, benzene, toluene, xylene, etc. can be used Inert solvents such as saturated aliphatic hydrocarbons or aromatic hydrocarbons are used as the reaction medium, and prepolymerization can be carried out before polymerization. The polymerization method can be batch, semi-continuous or continuous.

The polymerization temperature is from room temperature to 150°C, preferably from 50°C to 100°C. In order to adjust the molecular weight of the polymer, hydrogen is used as a molecular weight regulator.

Compared with the prior art, the present invention has the following obvious advantages: the catalyst component A of the present invention selects a specific inert solvent that is miscible with the titanium compound used as a coprecipitant to successfully produce a novel titanium-based polyolefin catalyst, and adopts the method The prepared catalyst has performance equivalent to or better than that of the catalyst described in the prior art, and the dissolution reaction step of the precipitation aid is omitted, and the method also has the following advantages: firstly, the addition of this type of coprecipitant is beneficial to the catalyst mother liquor Sedimentation and separation of the system, and secondly, the catalyst yield can be increased by using this method. Finally, this type of co-precipitant does not remain in the finished catalyst product, which helps to reduce the ash content of the polymerization product, thereby improving the quality of the polymer product.

Detailed ways:

(1) Preparation of catalyst

Example 1: In a reactor fully replaced by high-purity N ₂ , add 4.0 g of anhydrous MgCl ₂ , 50 ml of toluene, 2.0 ml of epichlorohydrin, and 3.0 ml of tributyl phosphate in sequence, and heat up to 50°C while stirring. And keep it for 15 minutes, add 6.0ml ethanol, continue to react for 15 minutes, cool the solution to -5°C, then drop the mixture of 30ml titanium tetrachloride and 30ml heptane into it, then raise the temperature to 40°C, filter After that, it was washed 4 times with hexane and dried in vacuum to obtain a solid catalyst.

Embodiment 2: same as embodiment 1, only the temperature at the end of heating is increased from 40°C to 105°C.

Embodiment 3: same as embodiment 1, only the heptane addition is changed into 20ml.

Embodiment 4: same as embodiment 1, only the heptane addition is changed into 40ml.

Embodiment 5: same as embodiment 1, only the heptane addition is changed into 60ml.

Embodiment 6: same as embodiment 1, only change heptane to decane, and the end temperature of heating is raised from 40 ℃ to 110 ℃.

Embodiment 7: same as embodiment 1, only change heptane into hexane.

Embodiment 8: same as embodiment 1, only change heptane into cyclohexane.

Example 9: Same as Example 1, only after the second washing with hexane, washing with a mixture of triethylaluminum and hexane is added, wherein the amount of triethylaluminum used is 0.002 moles.

Embodiment 10: same as embodiment 9, only when adding anhydrous magnesium chloride, add 0.5 gram of anhydrous zinc chloride.

Example 11: In a reactor fully replaced by high-purity N ₂ , add 4.0 g of anhydrous MgCl ₂ , 60 ml of toluene, 0.08 mole of epichlorohydrin, and 0.024 mole of tributyl phosphate in sequence, and raise the temperature to 50°C while stirring. And maintain it for 120 minutes, cool the solution to -25～-20°C, then drop the mixture of 45ml titanium tetrachloride and 45ml heptane into it, then slowly raise the temperature to 80°C, add diisophthalic acid 0.01 mol of butyl ester, maintained at 80°C for 60 minutes, filtered and washed twice with 60 ml of toluene. Then 60 ml of toluene and 40 ml of titanium tetrachloride were added, treated at 90° C. for 2 hours, filtered and then treated again. After filtration, it was washed twice with toluene and hexane respectively, and dried in vacuum to obtain a solid catalyst.

Comparative Example 1: In a reactor fully replaced by high-purity N ₂ , add 4.0g of anhydrous MgCl ₂ , 50ml of toluene, 2.0ml of epichlorohydrin, and 3.0ml of tributyl phosphate in sequence, and heat up to 50°C under stirring. And keep it for 15 minutes, add 6.0ml of ethanol, continue to react for 15 minutes, then add 0.5g of phthalic anhydride, keep it for another 30 minutes, cool the solution to -5～0℃, and then drop 20mL of titanium tetrachloride into Inside, the temperature was slowly raised to 40° C., filtered, washed with hexane four times, and dried in vacuum to obtain a solid catalyst.

Comparative example 2: same as embodiment 1, only change heptane into toluene.

Comparative example 3: same as embodiment 1, only heptane is canceled.

Comparative Example 4: In a reactor fully replaced by high-purity N ₂ , add 4.0 g of anhydrous MgCl ₂ , 60 ml of toluene, 0.08 mole of epichlorohydrin, and 0.024 mole of tributyl phosphate in sequence, and heat up to 50°C while stirring. And maintain it for 120 minutes, add 0.0064 moles of phthalic anhydride, continue the reaction for 60 minutes, cool the solution to -25～-20°C, then drop 45ml of titanium tetrachloride into it, and then slowly raise the temperature to 80°C, Add 0.01 mol of diisobutyl phthalate, maintain at 80° C. for 60 minutes, filter and wash twice with 60 ml of toluene. Then 60 ml of toluene and 40 ml of titanium tetrachloride were added, treated at 90° C. for 2 hours, filtered and then treated again. After filtration, it was washed twice with toluene and hexane respectively, and dried in vacuum to obtain a solid catalyst.

Comparative Example 5: Except that phthalic anhydride was not added, the rest of the operations were the same as in Comparative Example 4, but a solid catalyst could not be obtained.

(2) Ethylene polymerization: After the stainless steel kettle with a volume of 2 liters is fully replaced by H ₂ , add 1,000 ml of hexane and 1.5 ml of triethylaluminum in a hexane solution with a concentration of 1 mol/L, and measure (5 to 6 mg) of the above-mentioned The prepared solid catalyst component was heated up to 70°C and hydrogenated to 0.18MPa (gauge pressure), and then ethylene was introduced to make the inside of the kettle reach 0.73MPa (gauge pressure). At 80°C, it was polymerized for 2 hours. The polymerization results are shown in Table 1 .

(3) Copolymerization of ethylene: a stainless steel kettle with a volume of 2 liters was fully replaced by H ₂ , and 1000 ml of hexane, 10 ml of hexene, 1.5 ml of triethylaluminum (1mol/L hexane solution) were added therein, and metered ( 5-6 mg) of the solid catalyst component prepared in the above example 1, the temperature was raised to 70° C. for hydrogenation of 0.18 MPa (gauge pressure), and then ethylene was introduced to make the inside of the kettle reach 0.73 MPa (gauge pressure). At 80° C., polymerization After 2 hours, the polymerization results are shown in Table 1.

(4) Propylene polymerization: After the stainless steel kettle with a volume of 5 liters is fully replaced by propylene gas, 0.0008 moles of triethylaluminum and 0.0001 moles of diphenyldimethoxysilane are added therein, and the measured amount (6-8 mg) of the above-mentioned To the prepared solid catalyst component, 2.5 liters of liquid propylene was added, and then 1.0 standard liter of hydrogen was added, the temperature was raised to 70° C., and polymerization was carried out for 2 hours. The polymerization results are shown in Table 2.

Table 1:

Comparative example 1 Example 1 Example 2 Example 3 Example 4 Catalyst output (g) 4.0 6.2 6.0 5.1 6.5 Polymerization activity (10,000 gPE/gcat) 3.3 4.1 4.2 4.0 4.2 Example 5 Example 6 Example 7 Example 8 Example 9 Catalyst output (g) 6.3 6.5 6.4 5.6 6.3 Polymerization activity (10,000 gPE/gcat) 4.1 4.0 3.3 3.6 4.0 Example 10 Comparative example 2 Comparative example 3 Copolymerization Catalyst output (g) 6.2 1.2 0.8 6.2 Polymerization activity (10,000 gpE/gcat) 3.9 3.3 3.4 2.9

Table 2:

Comparative example 4 Comparative Example 5 Example 11 Catalyst output (g) 5.2 0 6.5 Polymerization activity (10,000 gPP/gcat) 5.4 ------ 5.8

Claims (15)

1. A catalyst for olefin polymerization, characterized in that it comprises the following components: A. The titanium-containing solid catalyst component is dissolved in an organic epoxy compound and an organic phosphorus compound by magnesium halide, and then added to an electron donor to form a uniform solution, and then mixed with a liquid co-precipitant and transition metal titanium halide or its derivatives obtained by the action of the mixture solution, wherein the electron donor is selected from one of organic alcohols and organic ethers or their mixture; the liquid coprecipitant is selected from hexane, heptane, octane, decane and cyclohexane ; B. An organoaluminum compound, the general formula of which is AlR _n X _3-n , where R is hydrogen, a hydrocarbon group with 1 to 20 carbon atoms, X is a halogen, and n is an integer of 0<n≤3; The ratio between component B and component A is 5-1000 in terms of molar ratio of aluminum to titanium. 2. The catalyst for olefin polymerization according to claim 1, characterized in that, the magnesium halide described in component A is dissolved in the process of forming a homogeneous solution, and an alkyl metal compound is added, wherein the alkyl metal compound refers to One or a mixture of alkylaluminum compounds or alkylzinc compounds. 3. The catalyst for olefin polymerization according to claim 2, characterized in that the metal alkyl compound added is triethylaluminum, triisobutylaluminum or diethylzinc. 4. The catalyst for olefin polymerization according to claim 1, characterized in that, the organic alcohol in the electron donor of component A includes C ₁ -C ₁₂ straight chain alcohol or isomeric alcohol. 5. according to the catalyst for olefin polymerization described in claim 4, it is characterized in that, the organic alcohol in the electron donor described in component A is methyl alcohol, ethanol, propanol, butanol, octanol, dodecyl alcohol Alcohol, glycerin, or a mixture thereof. 6. The catalyst for olefin polymerization according to claim 1, wherein the organic ether in the electron donor described in component A is one of methyl ether, diethyl ether, propyl ether, butyl ether, and pentyl ether species, or their mixtures. 7. The catalyst for olefin polymerization according to claim 1, characterized in that, the halide or derivative thereof of the transition metal Ti described in component A is titanium tetrachloride, titanium tetrabromide, tetraiodide One of titanium, tetrabutoxytitanium, tetraethoxytitanium, monochlorotriethoxytitanium, dichlorodiethoxytitanium, trichloromonoethoxytitanium or a mixture thereof. 8. The catalyst for olefin polymerization according to claim 1, characterized in that the volume ratio of the liquid coprecipitant to the halide of Ti is 0.1-10. 9. The catalyst for olefin polymerization according to claim 1, characterized in that the volume ratio of the liquid co-precipitant to the halide of Ti is 0.5-2.5. 10. The catalyst for olefin polymerization according to claim 1, characterized in that the molar ratio of the magnesium halide to the electron donor compound in the component A is 1:0.005-15. 11. The catalyst for olefin polymerization according to claim 1, characterized in that, when used for propylene polymerization, it is also necessary to add an external electron donor, whose general formula is R _n Si (OR') _4-n Organosilane, R and R' are the same or different hydrocarbon groups, halogenated hydrocarbon groups, where 0≤n≤3. 12. The preparation method of component A in the catalyst described in one of claims 1 to 10, under stirring, magnesium halide is dissolved in the organic epoxy compound and the organic phosphorus compound and then added to the electron donor, optionally adding the metal alkyl compound To form a uniform transparent solution, drop the mixture solution of transition metal titanium halide or its derivatives and liquid co-precipitation agent into the magnesium halide uniform solution or drop the magnesium halide solution into the transition metal titanium at a temperature of -35 ~ 60 °C In the mixture solution of the halide or its derivatives and the liquid co-precipitant, the reaction mixture is stirred at 0-130°C for 1 minute to 10 hours, the stirring is stopped, settled, filtered, the mother liquor is removed, and washed with toluene and hexane Solid matter, to prepare a titanium-containing solid catalyst component. 13. according to the preparation method of the described catalyst component A of claim 12, it is characterized in that, after stirring, settling, filtering, after removing mother liquor, with toluene and hexane and therein blending component B washes solid thing, makes containing Titanium solid catalyst component. 14. According to the preparation method of the catalyst component A described in claim 12, when it is used for propylene polymerization, it is also necessary to add polycarboxylic acid ester before or after the precipitation of solids for treatment. 15. according to the preparation method of the described catalyst component A of claim 12, it is characterized in that, in magnesium halide dissolving process, add alkyl metal compound, at-30～10 ℃, the halide of transition metal titanium or derivative thereof and The mixture solution of the liquid co-precipitation agent is dropped into the homogeneous magnesium halide solution or the magnesium halide solution is dropped into the mixture solution of the transition metal titanium halide or its derivatives and the liquid co-precipitation agent.