Solid catalyst component for olefin polymerization as well as preparation method, catalyst and application of solid catalyst component

Abstract

The invention belongs to the technical field of olefin polymerization, and relates to a solid catalyst component for olefin polymerization, and a preparation method, a catalyst and application thereof. The catalyst component comprises a reaction product of the following components: a magnesium source, a titanium source and an internal electron donor, the internal electron donor comprises a succinic acid monoester compound, a diol ester compound and a diether compound. The preparation method comprises the following steps: carrying out a contact reaction on a magnesium source and a titanium source, adding an internal electron donor in one or more time periods before, during and after the contact reaction of the magnesium source and the titanium source, carrying out one or more times of treatment by adopting the titanium source, and washing by using an inert solvent to obtain the solid catalyst component. The internal electron donor containing the succinic acid monoester compound, the diol ester compound and the diether compound is adopted, and the catalyst is a non-plasticizing type catalyst and has the advantages of being stable in polymerization activity release, high in stereospecificity, high in activity and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of olefin polymerization, and more specifically, relates to a solid catalyst component for olefin polymerization, a preparation method of the solid catalyst component, a catalyst containing the solid catalyst component, and application of the catalyst in olefin polymerization reactions. Background Art

[0002] The existing continuous process for preparing polyolefins often adopts a process flow of multiple reactors in series, such as two liquid phase bulk polymerization reactors in series, a liquid phase bulk polymerization reactor and a gas phase polymerization reactor in series, two or three gas phase reactors in series, etc. In the production process, the reaction residence time and other parameters in each reactor are controlled according to the performance requirements and process conditions of the specific product. The total residence time in each reactor is generally controlled at 2-4 hours, which requires the ZN catalyst used to release activity smoothly and evenly throughout the polymerization process. Otherwise, there will be problems such as excessive activity in the early stage, the reaction is difficult to control, and insufficient activity in the later stage. This will directly lead to a decrease in product quality or even failure to meet its performance requirements. It can be seen that the smooth and uniform release of the polymerization activity of the ZN catalyst is conducive to the stability and controllability of the polymerization process on the one hand; on the other hand, it is conducive to the adjustment of various parameters in the polymerization process to produce products with better performance.

[0003] In addition, the stereospecificity of the catalyst determines the isotactic index of the polymer. The higher the isotactic index of the polymer, the higher its regularity and crystallinity. The mechanical properties of the product, such as hardness, stiffness, modulus, fracture and yield strength, are increased. The melting point, thermal stability, aging resistance and radiation resistance are also improved accordingly. In order to develop high-performance polyolefin products, the stereospecificity of the catalyst should be further improved.

[0004] As an important component of Ziegler-Natta catalyst, internal electron donor compounds play a decisive role in important indicators such as polymerization activity and activity decay, hydrogen sensitivity, polymer isotacticity, polymer molecular weight and molecular weight distribution of the catalyst. With the development of electron donor compounds, polyolefin catalysts are constantly updated. There are many compounds that can be used as internal electron donors in Ziegler-Natta catalysts: polycarboxylic acids, carboxylates, anhydrides, ketones, ethers, etc. and their derivatives. Among them, dibasic aromatic carboxylic acid esters are more commonly used in industry, such as dibutyl phthalate or diisobutyl phthalate (US6365685B1, US20010020073A1), etc.

[0005] Although catalysts using phthalic acid diesters as internal electron donors have been widely used, the residues of phthalic acid diesters in polypropylene products during the use of such catalysts will affect human fertility. Countries have successively formulated corresponding regulations to restrict the use of plastic products with excessive phthalate content. Therefore, in the development of olefin polymerization catalysts, it is necessary to avoid the use of phthalic acid diester compounds in the preparation process.

[0006] Therefore, it is of great significance to develop a high stereospecific catalyst that does not contain phthalate compounds (plasticizers) and releases polymerization activity smoothly. Summary of the invention

[0007] The purpose of the present invention is to provide a catalyst component for olefin polymerization, a preparation method thereof, a catalyst and an application thereof. The obtained catalyst does not contain phthalate compounds (plasticizers) and has the characteristics of stable release of polymerization activity, high stereospecificity, high activity and the like.

[0008] In order to achieve the object of the present invention, the first aspect of the present invention provides a catalyst component for olefin polymerization, the catalyst component comprising a reaction product of the following components: a magnesium source, a titanium source and an internal electron donor;

[0009] Wherein, the internal electron donor comprises succinic acid monoester compounds, diol ester compounds and diether compounds.

[0010] The second aspect of the present invention provides a method for preparing the solid catalyst component for olefin polymerization, comprising the following steps:

[0011] A magnesium source is contacted with a titanium source for reaction, and an internal electron donor is added in one or more time periods before, during and after the contact reaction of the magnesium source and the titanium source, and then the titanium source is treated once or multiple times, and then washed with an inert solvent to obtain the solid catalyst component.

[0012] The third aspect of the present invention provides a catalyst for olefin polymerization, the catalyst comprising:

[0013] (i) the solid catalyst component;

[0014] (ii) at least one alkylaluminum compound; and

[0015] (iii) Optional external electron donor compound.

[0016] The fourth aspect of the present invention provides use of the catalyst for olefin polymerization in olefin polymerization reactions.

[0017] The present invention adopts an internal electron donor including succinic acid monoester compounds, diol ester compounds and diether compounds, and does not use phthalate compounds. Therefore, the catalyst is a non-plasticizer catalyst and has the characteristics of stable release of polymerization activity, high stereospecificity, high activity and the like.

[0018] Other features and advantages of the present invention will be described in detail in the following detailed description. DETAILED DESCRIPTION

[0019] The specific embodiments of the present invention are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0020] In order to achieve the object of the present invention, the first aspect of the present invention provides a catalyst component for olefin polymerization, the catalyst component comprising a reaction product of the following components: a magnesium source, a titanium source and an internal electron donor;

[0021] Wherein, the internal electron donor comprises succinic acid monoester compounds, diol ester compounds and diether compounds.

[0022] According to the present invention, based on the total weight of the internal electron donor, the total content of the succinic acid monoester compound, the diol ester compound and the diether compound is 70-100 weight %, preferably 80-100 weight %.

[0023] In the present invention, the succinic acid monoester compound may be any succinic acid monoester compound that can be used as an electron donor in a catalyst for olefin polymerization. Preferably, the succinic acid monoester compound is selected from at least one of the compounds represented by formula (1):

[0024]

[0025] In formula (1), R1 is C1-C 20 A straight or branched alkyl, cycloalkyl, aryl, aralkyl or alkaryl group, R2 to R5 are each independently selected from hydrogen, C1-C 20 The straight chain or branched chain alkyl, cycloalkyl, aryl, aralkyl or alkaryl group may contain heteroatoms, and R2 to R5 attached to the same carbon atom may be bonded to form a ring.

[0026] Preferably, the succinic acid monoester compound is selected from at least one of 4-methoxy-4-oxobutyric acid, 4-ethoxy-4-oxobutyric acid, 4-propoxy-4-oxobutyric acid, 4-tert-butoxy-4-oxobutyric acid, and 4-benzyl-4-oxobutyric acid; more preferably, the succinic acid monoester compound is 4-tert-butoxy-4-oxobutyric acid.

[0027] According to the present invention, the diol ester compound may be any diol ester compound that can be used as an electron donor in a catalyst for olefin polymerization, preferably a diol ester compound represented by formula I.

[0028]

[0029] In formula (2), R1 and R2 are the same or different and are each independently C1-C 10 Straight or branched alkyl, C3-C 20 Substituted or unsubstituted cycloalkyl, C6-C 20 Substituted or unsubstituted aryl, C7-C 20 Substituted or unsubstituted aralkyl and C7-C 20 wherein the aromatic ring of the aryl, aralkyl or alkaryl group is optionally substituted by one or more selected from halogen, C1-C6 straight-chain or branched alkyl and C1-C6 alkoxy; in Formula I, the brackets "[]" indicate that there are n carbon atoms bonded in sequence, and each carbon atom is also bonded to two substituents, that is, there are n carbon atoms and R in the brackets. 1 , R 2 , R 3 …R 2n And so on 2n substituents.

[0030] R3, R4, R5, R6 and R 1 -R 2n are the same or different and are each independently hydrogen, halogen, C1-C 20 Straight or branched alkyl, C3-C 20 Substituted or unsubstituted cycloalkyl, C6-C 20 Substituted or unsubstituted aryl, C7-C 20 Substituted or unsubstituted alkylaryl, C7-C 20 Substituted or unsubstituted aralkyl, C2-C 10 The straight chain or branched olefin group and C 10 -C 20 One of the fused ring aromatic groups, R3, R4, R5, R6 and R 1 -R 2n Optionally contain heteroatoms, said heteroatoms being one or more of nitrogen, oxygen, sulfur, silicon, halogen and phosphorus;

[0031] Alternatively, R3, R4, R5, R6 and R 1 -R 2n Two or more of them are bonded to each other to form a saturated or unsaturated ring;

[0032] n is an integer of 0-10. When n=0, in the diol ester compound represented by Formula I, the carbon atoms of the substituents R3 and R4 are directly bonded to the carbon atoms of the substituents R5 and R6;

[0033] In the present invention, C1-C 20 Examples of straight or branched alkyl groups may include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, 1-ethylpropyl, 2-methylbutyl, 3-methylbutyl, 2,2-dimethylpropyl, n-hexyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, n-heptyl, 2-methylhexyl, 3-methylhexyl, 4-methylhexyl, 5-methylhexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, tetrahydrogeranyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-octadecyl, n-nonadecyl, and n-eicosyl.

[0034] In the present invention, C3-C 20 Examples of the substituted or unsubstituted cycloalkyl group may include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 4-ethylcyclohexyl, 4-n-propylcyclohexyl, 4-n-butylcyclohexyl, cycloundecyl, and cyclododecyl.

[0035] In the present invention, C6-C 20 Examples of the substituted or unsubstituted aryl group may include, but are not limited to, phenyl, methylphenyl, ethylphenyl, 4-tert-butylphenyl, and the like.

[0036] In the present invention, C7-C 20 The substituted or unsubstituted aralkyl group refers to an alkyl group having 7 to 20 carbon atoms and having an aryl substituent. 20 Examples of the substituted or unsubstituted aralkyl group may include, but are not limited to, 3-phenylpropyl, benzyl, and the like.

[0037] In the present invention, C7-C 20 The substituted or unsubstituted alkaryl group refers to an aryl group having 7 to 20 carbon atoms and having an alkyl substituent. 20 Examples of the substituted or unsubstituted alkylaryl group may include, but are not limited to, methylphenyl, ethylphenyl, and the like.

[0038] In the present invention, examples of C1-C6 alkoxy groups may include, but are not limited to, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, sec-butoxy, isobutoxy, tert-butoxy, n-pentoxy, isopentyl, tert-pentyl and hexyloxy.

[0039] In the present invention, C2-C 10Examples of the straight or branched olefin group may include, but are not limited to, ethenyl, propenyl, butenyl, pentenyl, octenyl, and the like.

[0040] In the present invention, C 10 -C 20 Examples of the fused ring aromatic group may include, but are not limited to, naphthyl, anthracenyl, phenanthrenyl, pyrenyl, and the like.

[0041] According to the present invention, examples of the diol ester compounds may include, but are not limited to: 1,3-propylene glycol dibenzoate, 2-methyl-1,3-propylene glycol dibenzoate, 2-ethyl-1,3-propylene glycol dibenzoate, 2-propyl-1,3-propylene glycol dibenzoate, 2-butyl-1,3-propylene glycol dibenzoate, 2,2-dimethyl-1,3-propylene glycol dibenzoate, 2-ethyl-2-butyl-1,3-propylene glycol dibenzoate, 2,2-diethyl-1,3-propylene glycol dibenzoate, 2-methyl-2-propyl-1,3-propylene glycol dibenzoate, 2-isopropyl-2-isopentyl-1,3-propylene glycol dibenzoate, 2,4-pentanediol dibenzoate, 3-methyl-2, 4-Pentanediol Dibenzoate, 3-Ethyl-2,4-pentanediol Dibenzoate, 3-Propyl-2,4-pentanediol Dibenzoate, 3-Butyl-2,4-pentanediol Dibenzoate, 3,3-Dimethyl-2,4-pentanediol Dibenzoate, 2-Methyl-1,3-pentanediol Dibenzoate, 2,2-Dimethyl-1,3-pentanediol Dibenzoate, 2-Ethyl-1,3-pentanediol Dibenzoate, 2-Butyl-1,3-pentanediol Dibenzoate, 2-Methyl-1,3-pentanediol Dibenzoate, 2-Ethyl-1,3-pentanediol Dibenzoate, 2-Propyl-1,3-pentanediol Dibenzoate, 2-Butyl-1,3-pentanediol Dibenzoate, 2,2-Dimethyl-1,3-pentanediol Dibenzoate diol dibenzoate, 2-methyl-1,3-pentanediol dibenzoate, 2,2-dimethyl-1,3-pentanediol dibenzoate, 2-ethyl-1,3-pentanediol dibenzoate, 2-butyl-1,3-pentanediol dibenzoate, 2,2,4-trimethyl-1,3-pentanediol dibenzoate, 3-methyl-3-butyl-2,4-pentanediol dibenzoate, 2,2-dimethyl-1,5-pentanediol dibenzoate, 1,6-hexanediol dibenzoate, 6-heptene-2,4-heptanediol dibenzoate, 2-methyl-6-heptene-2,4-heptanediol dibenzoate, 3-methyl-6-heptene-2,4-heptanediol dibenzoate, 4-methyl-6-heptene-2,4-heptanediol dibenzoate 6-ethyl-6-heptene-2,4-heptanediol dibenzoate, 3-ethyl-6-heptene-2,4-heptanediol dibenzoate, 4-ethyl-6-heptene-2,4-heptanediol dibenzoate, 5-ethyl-6-heptene-2,4-heptanediol dibenzoate, 6-ethyl-6-heptene-2,4-heptanediol dibenzoate, 3-propyl-6-heptene-2,4-heptanediol dibenzoate, 4-propyl-6-heptene-2,4-heptanediol dibenzoate, 5-propyl-6-heptene-2,4-heptanediol dibenzoate, 6-propyl-6-heptene-2,4-heptanediol dibenzoate, 3-butyl-6-heptene-2,4-heptene-2,4-heptene diol dibenzoate, 4-butyl-6-heptene-2,4-heptene diol dibenzoate, 5-butyl-6-heptene-2,4-heptene diol dibenzoate, 6-butyl-6-heptene-2,4-heptene diol dibenzoate, 3,5-dimethyl-6-heptene-2,4-heptene diol dibenzoate, 3,5-diethyl-6-heptene-2,4-heptene diol dibenzoate, 3,5-dipropyl-6-heptene-2,4-heptene diol dibenzoate, 3,5-dibutyl-6-heptene-2,4-heptene diol dibenzoate, 3,3-dimethyl-6-heptene-2,4-heptene diol dibenzoate, 3,3-diethyl-6-heptene-2,4-heptene diol dibenzoate, 3,3-dipropyl-6-heptene-2,4-heptene diol dibenzoate Heptene-2,4-heptanediol dibenzoate, 3,3-dibutyl-6-heptene-2,4-heptanediol dibenzoate, 3,5-heptanediol dibenzoate, 2-methyl-3,5-heptanediol dibenzoate, 3-methyl-3,5-heptanediol dibenzoate, 4-methyl-3,5-heptanediol dibenzoate, 5-methyl-3,5-heptanediol dibenzoate, 6-methyl-3,5-heptanediol dibenzoate, 3-ethyl-3,5-heptanediol dibenzoate, 4-ethyl-3,5-heptanediol dibenzoate, 5-ethyl-3,5-heptanediol dibenzoate, 3-propyl-3,5-heptanediol dibenzoate, 4-propyl-3,5-heptanediol dibenzoate, 3-butyl-3,5-heptanediol dibenzoate, 2,3-dimethyl-3,5-heptanediol dibenzoate, 2,4-dimethyl-3,5-heptanediol dibenzoate, 2,5-dimethyl-3,5-heptanediol dibenzoate, 2,6-dimethyl-3,5-heptanediol dibenzoate, 3,3-dimethyl-3,5-heptanediol dibenzoate, 4,4-dimethyl-3,5-heptanediol dibenzoate, 6,6-dimethyl-3,5-heptanediol dibenzoate, 2,6-dimethyl-3,5-heptanediol dibenzoate, 3,4-dimethyl-3,5-heptanediol dibenzoate, 3,5-dimethyl-3,5-heptanediol dibenzoate, 3,6-dimethyl-3,5-heptanediol dibenzoate, 4,5-dimethyl-3, 5-heptanediol dibenzoate, 4,6-dimethyl-3,5-heptanediol dibenzoate, 4,4-dimethyl-3,5-heptanediol dibenzoate, 6,6-dimethyl-3,5-heptanediol dibenzoate, 2-methyl-3-ethyl-3,5-heptanediol dibenzoate, 2-methyl-4-ethyl-3,5-heptanediol dibenzoate, 2-methyl-5-ethyl-3,5-heptanediol dibenzoate, 3-methyl-3-ethyl-3,5-heptanediol dibenzoate, 3-methyl-4-ethyl-3,5-heptanediol dibenzoate, 3-methyl-5-ethyl-3,5-heptanediol dibenzoate, 4-methyl-3-ethyl-3,5-heptanediol dibenzoate, 4-methyl-4-ethyl-3,5-heptanediol dibenzoate, 4-methyl-5-ethyl-3,5-heptanediol dibenzoate, 2-methyl-3-propyl-3,5-heptanediol dibenzoate, 2-methyl-4-propyl-3,5-heptanediol dibenzoate, 2-methyl-5-propyl-3,5-heptanediol dibenzoate, 3-methyl-3-propyl-3,5-heptanediol dibenzoate, 3-methyl-4-propyl-3,5-heptanediol dibenzoate, 3-methyl-5-propyl-3,5-heptanediol dibenzoate, 4-methyl-3-propyl-3,5-heptanediol dibenzoate, 4-methyl-4-propyl-3,5-heptanediol dibenzoate, 4-methyl-5-propyl-3,5-heptanediol dibenzoate, etc.

[0042] More preferably, the diol ester compound is 2,4-pentanediol dibenzoate and / or 3,5-heptanediol dibenzoate.

[0043] According to the present invention, the diether compound may be any diether compound that can be used as an electron donor in a catalyst for olefin polymerization. Preferably, the diether compound is selected from at least one of the diether compounds represented by formula (3):

[0044]

[0045] In formula (3), R Ⅰ , R Ⅱ , R Ⅲ , R Ⅳ , R Ⅴ and R Ⅵ the same or different, each independently selected from hydrogen, halogen atoms, C1-C 20 Straight or branched alkyl, C3-C 20 Cycloalkyl, C6-C 20 Aryl, C7-C 20 Arylalkyl or C7-C 20 The alkylaryl group, R Ⅰ -R Ⅵ The groups of R may be optionally bonded to form a ring; Ⅶ and R Ⅷ The same or different, each independently selected from C1-C 20 Straight or branched alkyl, C3-C 20 Cycloalkyl, C6-C 20 Aryl, C7-C 20 Alkyl or C7-C 20 of aralkyl.

[0046] Preferably, the diether compound is selected from 2-(2-ethylhexyl)-1,3-dimethoxypropane, 2-isopropyl-1,3-dimethoxypropane, 2-butyl-1,3-dimethoxypropane, 2-sec-butyl-1,3-dimethoxypropane, 2-cyclohexyl-1,3-dimethoxypropane, 2-phenyl-1,3-dimethoxypropane, 2-(2-phenylethyl)-1,3-dimethoxypropane, 2-(2-cyclohexylethyl)-1,3-dimethoxypropane, 2-(p-chlorophenyl)-1,3-dimethoxypropane, 2-(diphenylmethyl)-1,3-dimethoxypropane, 2,2-dicyclohexyl-1,3-dimethoxypropane, 2 ,2-dicyclopentyl-1,3-dimethoxypropane, 2,2-diethyl-1,3-dimethoxypropane, 2,2-dipropyl-1,3-dimethoxypropane, 2,2-diisopropyl-1,3-dimethoxypropane, 2,2-dibutyl-1,3-dimethoxypropane, 2-methyl-2-propyl-1,3-dimethoxypropane, 2-methyl-2-benzyl-1,3-dimethoxypropane, 2-methyl-2-ethyl-1,3-dimethoxypropane, 2-methyl-2-isopropyl-1,3-dimethoxypropane, 2-methyl-2-phenyl-1,3-dimethoxypropane, 2-methyl-2-cyclohexyl-1,3-dimethoxypropane, 2,2- Bis(2-cyclohexylethyl)-1,3-dimethoxypropane, 2-methyl-2-isobutyl-1,3-dimethoxypropane, 2-methyl-2-(2-ethylhexyl)-1,3-dimethoxypropane, 2,2-diisobutyl-1,3-dimethoxypropane, 2,2-diphenyl-1,3-dimethoxypropane, 2,2-dibenzyl-1,3-dimethoxypropane, 2,2-bis(cyclohexylmethyl)-1,3-dimethoxypropane, 2-isobutyl-2-isopropyl-1,3-dimethoxypropane, 2-(1-methylbutyl)-2-isopropyl-1,3-dimethoxypropane, 2-isopropyl-2-isopentyl-1,3-dimethoxypropane, At least one of 2-phenyl-2-isopropyl-1,3-dimethoxypropane, 2-phenyl-2-sec-butyl-1,3-dimethoxypropane, 2-benzyl-2-isopropyl-1,3-dimethoxypropane, 2-cyclopentyl-2-isopropyl-1,3-dimethoxypropane, 2-cyclopentyl-2-sec-butyl-1,3-dimethoxypropane, 2-cyclohexyl-2-isopropyl-1,3-dimethoxypropane, 2-cyclohexyl-2-sec-butyl-1,3-dimethoxypropane, 2-isopropyl-2-sec-butyl-1,3-dimethoxypropane, 2-cyclohexyl-2-cyclohexylmethyl-1,3-dimethoxypropane and 9,9-dimethoxymethylfluorene.

[0047] More preferably, the diether compound is 2-isopropyl-2-isopentyl-1,3-dimethoxypropane or 9,9-dimethoxymethylfluorene.

[0048] According to the present invention, the molar ratio of the succinic acid monoester compound, the diol ester compound and the diether compound is 0.1-1.2: 0.1-1.0: 1, and more preferably 0.15-0.75: 0.12-0.65: 1. The above preferred amounts of the three can be better coordinated, the polymerization activity of the catalyst is released smoothly, and it has high stereospecificity.

[0049] In the present invention, the magnesium source can be various magnesium-containing compounds that can be used for olefin polymerization catalysts, for example, the magnesium source can be a magnesium halide, an alcoholate of magnesium, a halogenated alcoholate of magnesium, or a magnesium halide adduct carrier, etc. The magnesium halide can be, for example, magnesium chloride and / or magnesium bromide. The alcoholate of magnesium can be, for example, diethoxymagnesium. The halogenated alcoholate of magnesium can be, for example, ethoxymagnesium chloride. The types of the magnesium halide adduct carrier are well known to those skilled in the art, for example, the magnesium halide adduct carriers disclosed in patent documents CN1091748, CN101050245, CN101486722, CN102796132B, CN102796129B and CN102796128B, and the relevant contents disclosed in these patent documents are all introduced into the present invention as a reference.

[0050] According to the present invention, the titanium source can be a conventional choice in the art, for example, the titanium source can be a titanium source having a general formula of Ti(OR′) 3-a Z a and / or Ti(OR′) 4-b Z b A titanium compound wherein R′ is C1-C 20 alkyl, Z is F, Cl, Br or I, a is an integer of 1 to 3, and b is an integer of 1 to 4. Preferably, the titanium source is one or more of titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, tributoxytitanium chloride, dibutoxytitanium dichloride, butoxytitanium trichloride, triethoxytitanium chloride, diethoxytitanium dichloride, ethoxytitanium trichloride and titanium trichloride.

[0051] In the catalyst component of the present invention, the content of magnesium element is 2-16 parts by weight, preferably 3-15 parts by weight, and more preferably 4-13 parts by weight per part by weight of titanium element; the content of internal electron donor is 2-17 parts by weight, preferably 3-15 parts by weight, and more preferably 4-13 parts by weight.

[0052] The second aspect of the present invention provides a method for preparing the solid catalyst component for olefin polymerization, comprising the following steps:

[0053] A magnesium source is contacted with a titanium source for reaction, and an internal electron donor is added in one or more time periods before, during and after the contact reaction of the magnesium source and the titanium source, and then the titanium source is treated once or multiple times, and then washed with an inert solvent to obtain the solid catalyst component.

[0054] The time period before the reaction of the magnesium source and the titanium source refers to the time period after the magnesium source is added to the reactor and before the temperature is raised to the reaction temperature.

[0055] Preferably, the reaction of the magnesium source and the titanium source can be carried out in the following manner: the titanium source is cooled to below 0°C (preferably -10 to -30°C), and then the magnesium source is added and stirred and mixed at this temperature, preferably for 10-60 minutes, and then the temperature is gradually raised to the reaction temperature (i.e., about 60-130°C), and the succinic acid monoester compound, the diol ester compound and the diether compound are added during the heating process, and the reaction temperature is maintained for 0.2-10 hours, preferably 0.5-5 hours. Then, the titanium source is used for treatment, and then the inert solvent is used for washing.

[0056] In the present invention, the molar ratio of the amount of the magnesium source calculated as magnesium element, the titanium source calculated as titanium element and the internal electron donor can be 1:12-200:0.1-1.5. Preferably, the molar ratio of the amount of the magnesium source calculated as magnesium element, the titanium source calculated as titanium element and the internal electron donor is 1:15-180:0.15-1.2.

[0057] The third aspect of the present invention provides a catalyst for olefin polymerization, the catalyst comprising:

[0058] (i) the solid catalyst component;

[0059] (ii) at least one alkylaluminum compound; and

[0060] (iii) Optional external electron donor compound.

[0061] In the present invention, the alkyl aluminum compound may be any of various alkyl aluminum compounds commonly used in the art. For example, the general formula of the alkyl aluminum may be AlR n X 3-n , wherein R is a C1-C8 alkyl group, the hydrogen on the alkyl group is optionally replaced by a halogen atom, X is a halogen, and n is 1, 2 or 3.

[0062] Specific examples of the C1-C8 alkyl group may include, but are not limited to, methyl, ethyl, propyl, n-butyl, isobutyl, pentyl, hexyl, n-heptyl, and n-octyl, and the halogen may include fluorine, chlorine, bromine, and iodine.

[0063] Specifically, the alkylaluminum compound can be selected from one or more of triethylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri-n-hexylaluminum, diethylaluminum monochloride, diisobutylaluminum monochloride, di-n-butylaluminum monochloride, di-n-hexylaluminum monochloride, monoethylaluminum dichloride, monoisobutylaluminum dichloride, mono-n-butylaluminum dichloride and mono-n-hexylaluminum dichloride.

[0064] According to the present invention, the amount of the alkyl aluminum compound can be the conventional amount in the art. The molar ratio of aluminum in the alkyl aluminum compound to titanium in the catalyst component can be 1-2000:1, preferably 20-500:1, more preferably 30-300:1.

[0065] In the present invention, the external electron donor can be any of various external electron donors commonly used in the art. For example, the external electron donor can be selected from at least one of carboxylic acids, carboxylic anhydrides, carboxylic esters, ketones, ethers, alcohols, lactones, organophosphorus compounds and organosilicon compounds.

[0066] Preferably, the external electron donor is selected from a group containing at least one Si-OR 19 bond, and the general formula is (R 17 ) x (R 18 ) y Si(OR 19 ) z Silicon compounds, where R 17 , R 18 and R 19 C1-C 18 The hydrocarbon group optionally contains heteroatoms, x and y are each independently an integer of 0-2, z is an integer of 1-3, and the sum of x, y, and z is 4. 17 , R 18 Preferably C3-C 10 The alkyl or cycloalkyl group may contain heteroatoms; R 19 Preferably C1-C 10 The alkyl group may contain a heteroatom.

[0067] Specifically, the external electron donor can be selected from at least one of cyclohexylmethyldimethoxysilane, diisopropyldimethoxysilane, di-n-butyldimethoxysilane, diisobutyldimethoxysilane, diphenyldimethoxysilane, methyl-tert-butyldimethoxysilane, dicyclopentyldimethoxysilane, 2-ethylpiperidinyl-2-tert-butyldimethoxysilane, (1,1,1-trifluoro-2-propyl)-2-ethylpiperidinyldimethoxysilane and (1,1,1-, trifluoro-2-propyl)-methyldimethoxysilane.

[0068] According to the present invention, the amount of the external electron donor can be a conventional amount in the art. The molar ratio of the external electron donor to the aluminum in the alkyl aluminum compound can be 1:1-300, preferably 1:2-100.

[0069] The fourth aspect of the present invention provides use of the catalyst for olefin polymerization in olefin polymerization reactions.

[0070] When the catalyst of the present invention is used for olefin polymerization, the catalyst components, alkyl aluminum compound, and optional external electron donor can be added to the polymerization reactor separately, or mixed and added to the polymerization reactor, or the olefin can be prepolymerized by a prepolymerization method known in the industry and then added to the polymerization reactor.

[0071] In the present invention, the specific type of olefin, the polymerization method and conditions of olefin can be conventionally selected according to the prior art.

[0072] The catalyst of the present invention is particularly suitable for the general formula CH2=CHR 1 Homopolymerization and copolymerization of olefins, wherein R 1 is hydrogen, C1-C6 alkyl or C6-C 12 The aromatic group.

[0073] According to the present invention, the polymerization reaction of the olefin can be carried out according to the existing method, specifically, under the protection of an inert gas, in a liquid phase monomer or an inert solvent containing a polymerizable monomer, or in a gas phase, or by a combined polymerization process in a gas-liquid phase. The temperature of the polymerization reaction can generally be 0-150°C, preferably 60-90°C. The pressure of the polymerization reaction can be normal pressure or higher, for example, 0.01-10MPa, preferably 0.01-5MPa, more preferably 0.1-4Mpa, and the pressure of the present invention refers to the gauge pressure. In the polymerization process, hydrogen can be used as a polymer molecular weight regulator and added to the reaction system to adjust the molecular weight and melt index of the polymer. In addition, in the polymerization process of the olefin, the type and amount of the inert gas and solvent are well known to those skilled in the art and will not be repeated here.

[0074] Parameters not limited in the present invention are all conventional technical means in the art.

[0075] The present invention will be further described below in conjunction with embodiments, but the scope of the present invention is not limited to these embodiments.

[0076] The isotactic index of the polymer in the present invention is determined by the heptane extraction method (heptane boiling extraction for 6 hours), that is, 2 g of a dry polymer sample is taken, placed in an extractor and extracted with boiling heptane for 6 hours, then the residue is dried to constant weight, and the ratio of the obtained polymer weight (g) to 2 is the isotactic index.

[0077] Examples 1 to 18 are used to illustrate the catalyst components and catalysts for olefin polymerization and their applications according to the present invention.

[0078] Example 1

[0079] (1) Preparation of catalyst components

[0080] In a 300 mL glass reaction bottle, add 80 mL of titanium tetrachloride and cool to -20°C, add 38 mmol of a magnesium halide carrier (prepared according to the method disclosed in Example 1 of CN1267508C) in terms of magnesium element, then heat to 115°C, and add 1.2 mmol of 4-tert-butoxy-4-oxobutyric acid, 1 mmol of 2,4-pentanediol dibenzoate and 6.5 mmol of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane during the heating process. After maintaining at 115°C for 30 min, filter out the liquid, wash with titanium tetrachloride, then wash with hexane, and vacuum dry to obtain the catalyst component Cat-1 for olefin polymerization.

[0081] (2) Propylene liquid phase bulk polymerization

[0082] The bulk polymerization of propylene in liquid phase was carried out in a 5L stainless steel autoclave. Under nitrogen protection, 2mL of triethylaluminum hexane solution (concentration of 0.5mmol / mL), 0.4mL of cyclohexylmethyldimethoxysilane (CHMMS) hexane solution (concentration of 0.1mmol / mL) and 9.6mg of the above-mentioned catalyst component Cat-1 for olefin polymerization were added to the autoclave in sequence. The autoclave was closed and 2.3L of liquid propylene was added. The temperature was raised to 70°C, and after reacting for 1 hour, the temperature was lowered, the pressure was released, the material was discharged, and the obtained propylene homopolymer was dried, weighed and analyzed. The isotactic index of the obtained polymer was 99.3%.

[0083] Example 2

[0084] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 1, except that 1.5 NL of hydrogen was added after the autoclave was closed.

[0085] Example 3

[0086] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 2, except that the reaction was carried out for 2 hours.

[0087] Example 4

[0088] The catalyst component was prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 1, except that 2.6 mmol of 4-tert-butoxy-4-oxobutyric acid, 1.5 mmol of 2,4-pentanediol dibenzoate and 6.2 mmol of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were added during the heating process to obtain a catalyst component Cat-2 for olefin polymerization. The isotactic index of the obtained polymer was 99.6%.

[0089] Example 5

[0090] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 4, except that 1.5 NL of hydrogen was added after the autoclave was closed.

[0091] Example 6

[0092] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 5, except that the reaction was carried out for 2 hours.

[0093] Example 7

[0094] The catalyst component was prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 1, except that 3.5 mmol of 4-tert-butoxy-4-oxobutyric acid, 2.5 mmol of 3,5-heptanediol dibenzoate and 5.8 mmol of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were added during the heating process to obtain a catalyst component Cat-3 for olefin polymerization. The isotactic index of the obtained polymer was 99.7%.

[0095] Example 8

[0096] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 7, except that 1.5 NL of hydrogen was added after the autoclave was closed.

[0097] Example 9

[0098] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 7, except that the reaction was carried out for 2 hours.

[0099] Example 10

[0100] The catalyst component was prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 1, except that 3.9 mmol of 4-tert-butoxy-4-oxobutyric acid, 3.2 mmol of 2,4-pentanediol dibenzoate and 5.2 mmol of 9,9-dimethoxymethylfluorene were added during the heating process to obtain a catalyst component Cat-4 for olefin polymerization. The isotactic index of the obtained polymer was 99.3%.

[0101] Embodiment 11

[0102] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 10, except that 1.5 NL of hydrogen was added after closing the autoclave.

[0103] Example 12

[0104] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 10, except that the reaction was carried out for 2 hours.

[0105] Embodiment 13

[0106] The catalyst component was prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 1, except that 4.5 mmol of 4-tert-butoxy-4-oxobutyric acid, 3.9 mmol of 2,4-pentanediol dibenzoate and 4.3 mmol of 9,9-dimethoxymethylfluorene were added during the heating process to obtain the catalyst component Cat-5 for olefin polymerization. The isotactic index of the obtained polymer was 98.8%.

[0107] Embodiment 14

[0108] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 13, except that 1.5 NL of hydrogen was added after closing the autoclave.

[0109] Embodiment 15

[0110] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 13, except that the reaction was carried out for 2 hours.

[0111] Example 16

[0112] The catalyst component was prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 1, except that 3 mmol of 2,4-pentanediol dibenzoate, 2 mmol of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane and 4 mmol of 4-tert-butoxy-4-oxobutyric acid were added during the preparation of the catalyst component to obtain a catalyst component Cat-6 for olefin polymerization; the obtained propylene homopolymer was dried, weighed and analyzed. The isotactic index of the obtained polymer was 98.3%.

[0113] Embodiment 17

[0114] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 16, except that 1.5 NL of hydrogen was added after closing the autoclave.

[0115] Embodiment 18

[0116] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 16, except that the reaction was carried out for 2 hours.

[0117] Comparative Example 1

[0118] The catalyst component was prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 1, except that during the preparation of the catalyst component, 4-tert-butoxy-4-oxobutyric acid and 2,4-pentanediol dibenzoate were not added, and only 8.7 mmol of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane was added to obtain a catalyst component DCat-1 for olefin polymerization; the obtained propylene homopolymer was dried, weighed and analyzed. The isotactic index of the obtained polymer was 97.9%.

[0119] Comparative Example 2

[0120] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Comparative Example 1, except that 1.5 NL of hydrogen was added after the autoclave was closed.

[0121] Comparative Example 3

[0122] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Comparative Example 1, except that the reaction was carried out for 2 hours.

[0123] Comparative Example 4

[0124] The catalyst component was prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 1, except that during the preparation of the catalyst component, 4-tert-butoxy-4-oxobutyric acid and 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were not added, and only 8.7 mmol of 2,4-pentanediol dibenzoate was added to obtain a catalyst component DCat-2 for olefin polymerization; the obtained propylene homopolymer was dried, weighed and analyzed. The isotactic index of the obtained polymer was 97.5%.

[0125] Comparative Example 5

[0126] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Comparative Example 4, except that 1.5 NL of hydrogen was added after the autoclave was closed.

[0127] Comparative Example 6

[0128] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Comparative Example 4, except that the reaction was carried out for 2 hours.

[0129] Comparative Example 7

[0130] The catalyst component was prepared and propylene liquid phase bulk polymerization was carried out according to the method of Example 1, except that during the preparation of the catalyst component, 2,4-pentanediol dibenzoate and 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were not added, and only 8.7 mmol of 4-tert-butoxy-4-oxobutyric acid was added to obtain a catalyst component DCat-3 for olefin polymerization; the obtained propylene homopolymer was dried, weighed and analyzed. The isotactic index of the obtained polymer was 68.1%.

[0131] Comparative Example 8

[0132] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Comparative Example 7, except that 1.5 NL of hydrogen was added after the autoclave was closed.

[0133] Comparative Example 9

[0134] The catalyst components were prepared and propylene liquid phase bulk polymerization was carried out according to the method of Comparative Example 7, except that the reaction was carried out for 2 hours.

[0135] The test data of the embodiments and comparative examples are shown in Table 1:

[0136] Table 1

[0137]

[0138]

[0139] It can be seen from the data of the embodiments and comparative examples that when the internal electron donor contains succinic acid monoester compounds, diol ester compounds and diether compounds, the catalyst has both high stereospecificity and low activity decay rate, and the catalyst component of the present invention does not contain phthalate compounds (plasticizers).

[0140] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

[0141] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

Claims

1. A catalyst component for olefin polymerization, characterized in that The catalyst component comprises the reaction product of the following components: a magnesium source, a titanium source and an internal electron donor; Wherein, the internal electron donor comprises succinic acid monoester compounds, diol ester compounds and diether compounds.

2. The catalyst component for olefin polymerization according to claim 1, wherein Based on the total weight of the internal electron donor, the total content of the succinic acid monoester compound, the diol ester compound and the diether compound is 70-100 weight %, preferably 80-100 weight %.

3. The catalyst component for olefin polymerization according to claim 1, wherein The succinic acid monoester compound is selected from at least one of the succinic acid monoester compounds shown in formula (1), In formula (1), R1 is C1-C 20 Straight chain alkyl, C3-C 20 Branched alkyl, C3-C 20 Cycloalkyl, C6-C 20 Aryl, C7-C 20 Alkyl or C7-C 20 R2 to R5 are each independently selected from hydrogen, C1-C 20 Straight chain alkyl, C3-C 20 Branched alkyl, C3-C 20 Cycloalkyl, C6-C 20 Aryl, C7-C 20 Alkyl or C7-C 20 The aralkyl group may contain a heteroatom, and R2 to R5 attached to the same carbon atom may be bonded to form a ring; Preferably, the succinic acid monoester compound is selected from at least one of 4-methoxy-4-oxobutyric acid, 4-ethoxy-4-oxobutyric acid, 4-propoxy-4-oxobutyric acid, 4-tert-butoxy-4-oxobutyric acid and 4-benzyl-4-oxobutyric acid; More preferably, the succinic acid monoester compound is 4-tert-butoxy-4-oxobutanoic acid.

4. The catalyst component for olefin polymerization according to claim 1, wherein The diol ester compound is selected from at least one of the diol ester compounds represented by formula (2), In formula (2), R1 and R2 are the same or different and are each independently C1-C 10 Straight chain alkyl, C3-C 10 Branched alkyl, C3-C 20 Substituted or unsubstituted cycloalkyl, C6-C 20 Substituted or unsubstituted aryl, C7-C 20 Substituted or unsubstituted aralkyl and C7-C 20 wherein the aromatic ring of the aryl, aralkyl or alkaryl group is optionally substituted by one or more selected from halogen, C1-C6 straight-chain or branched alkyl and C1-C6 alkoxy; in formula (2), the brackets "[]" indicate that there are n carbon atoms bonded in sequence, and each carbon atom is also bonded to two substituents, that is, there are n carbon atoms and R in the brackets. 1 , R 2 , R 3 …R 2n etc. 2n substituents; R3, R4, R5, R6 and R 1 -R 2n are the same or different and are independently hydrogen, halogen, C1-C 20 Straight chain alkyl, C3-C 20 Branched alkyl, C3-C 20 Substituted or unsubstituted cycloalkyl, C6-C 20 Substituted or unsubstituted aryl, C7-C 20 Substituted or unsubstituted alkylaryl, C7-C 20 Substituted or unsubstituted aralkyl, C2-C 10 Straight chain olefin groups, C3-C 10 Branched olefin or C 10 -C 20 The condensed ring aromatic group, R3, R4, R5, R6 and R 1 -R 2n Optionally contain heteroatoms, the heteroatoms are one or more of nitrogen, oxygen, sulfur, silicon, halogen and phosphorus; or, R3, R4, R5, R6 and R 1 -R 2n Two or more of them are bonded to each other to form a saturated or unsaturated ring; n is an integer of 0-10. When n=0, in the diol ester compound represented by Formula I, the carbon atoms of the substituents R3 and R4 are directly bonded to the carbon atoms of the substituents R5 and R6; Preferably, the diol ester compound is selected from 1,3-propylene glycol dibenzoate, 2-methyl-1,3-propylene glycol dibenzoate, 2-ethyl-1,3-propylene glycol dibenzoate, 2-propyl-1,3-propylene glycol dibenzoate, 2-butyl-1,3-propylene glycol dibenzoate, 2,2-dimethyl-1,3-propylene glycol dibenzoate, 2-ethyl-2-butyl-1,3-propylene glycol dibenzoate, 2,2-diethyl-1,3-propylene glycol dibenzoate, 2-methyl-2-propyl-1,3-propylene glycol dibenzoate, 2-isopropyl-2-isopentyl-1,3-propylene glycol dibenzoate, 2,4-pentanediol dibenzoate, 3-methyl-2,4-pentanediol dibenzoate, 3-ethyl -2,4-pentanediol dibenzoate, 3-propyl-2,4-pentanediol dibenzoate, 3-butyl-2,4-pentanediol dibenzoate, 3,3-dimethyl-2,4-pentanediol dibenzoate, 2-methyl-1,3-pentanediol dibenzoate, 2,2-dimethyl-1,3-pentanediol dibenzoate, 2-ethyl-1,3-pentanediol dibenzoate, 2-butyl-1,3-pentanediol dibenzoate, 2-methyl-1,3-pentanediol dibenzoate, 2-ethyl-1,3-pentanediol dibenzoate, 2-propyl-1,3-pentanediol dibenzoate, 2-butyl-1,3-pentanediol dibenzoate, 2,2-dimethyl-1,3-pentanediol dibenzoate, 2-methyl-1,3-pentanediol dibenzoate diol dibenzoate, 2,2-dimethyl-1,3-pentanediol dibenzoate, 2-ethyl-1,3-pentanediol dibenzoate, 2-butyl-1,3-pentanediol dibenzoate, 2,2,4-trimethyl-1,3-pentanediol dibenzoate, 3-methyl-3-butyl-2,4-pentanediol dibenzoate, 2,2-dimethyl-1,5-pentanediol dibenzoate, 1,6-hexanediol dibenzoate, 6-heptene-2,4-heptanediol dibenzoate, 2-methyl-6-heptene-2,4-heptanediol dibenzoate, 3-methyl-6-heptene-2,4-heptanediol dibenzoate, 4-methyl-6-heptene-2,4-heptanediol dibenzoate, 5-methyl-6-heptene-2,4-heptanediol dibenzoate 6-Methyl-6-heptene-2,4-heptanediol dibenzoate, 3-ethyl-6-heptene-2,4-heptanediol dibenzoate, 4-ethyl-6-heptene-2,4-heptanediol dibenzoate, 5-ethyl-6-heptene-2,4-heptanediol dibenzoate, 6-ethyl-6-heptene-2,4-heptanediol dibenzoate, 3-propyl-6-heptene-2,4-heptanediol dibenzoate, 4-propyl-6-heptene-2,4-heptanediol dibenzoate, 5-propyl-6-heptene-2,4-heptanediol dibenzoate, 6-propyl-6-heptene-2,4-heptanediol dibenzoate, 3-butyl-6-heptene-2,4-heptanediol dibenzoate, 4-butyl-6-heptene-2,4-heptanediol dibenzoate, 5-butyl-6-heptene-2,4-heptanediol dibenzoate, 6-butyl-6-heptene-2,4-heptanediol dibenzoate, 3,5-dimethyl-6-heptene-2,4-heptanediol dibenzoate, 3,5-diethyl-6-heptene-2,4-heptanediol dibenzoate, 3,5-dipropyl-6-heptene-2,4-heptanediol dibenzoate, 3,5-dibutyl-6-heptene-2,4-heptanediol dibenzoate, 3,3-dimethyl-6-heptene-2,4-heptanediol dibenzoate, 3,3-diethyl-6-heptene-2,4-heptanediol dibenzoate, 3,3-dipropyl-6-heptene-2,4-heptanediol dibenzoate, 3,3-dibutyl -6-heptene-2,4-heptanediol dibenzoate, 3,5-heptanediol dibenzoate, 2-methyl-3,5-heptanediol dibenzoate, 3-methyl-3,5-heptanediol dibenzoate, 4-methyl-3,5-heptanediol dibenzoate, 5-methyl-3,5-heptanediol dibenzoate, 6-methyl-3,5-heptanediol dibenzoate, 3-ethyl-3,5-heptanediol dibenzoate, 4-ethyl-3,5-heptanediol dibenzoate, 5-ethyl-3,5-heptanediol dibenzoate, 3-propyl-3,5-heptanediol dibenzoate, 4-propyl-3,5-heptanediol dibenzoate, 3-butyl-3,5-heptanediol dibenzoate, 2,3-dimethyl-3,5-heptanediol dibenzoate dibenzoate, 2,4-dimethyl-3,5-heptanediol dibenzoate, 2,5-dimethyl-3,5-heptanediol dibenzoate, 2,6-dimethyl-3,5-heptanediol dibenzoate, 3,3-dimethyl-3,5-heptanediol dibenzoate, 4,4-dimethyl-3,5-heptanediol dibenzoate, 6,6-dimethyl-3,5-heptanediol dibenzoate, 2,6-dimethyl-3,5-heptanediol dibenzoate, 3,4-dimethyl-3,5-heptanediol dibenzoate, 3,5-dimethyl-3,5-heptanediol dibenzoate, 3,6-dimethyl-3,5-heptanediol dibenzoate, 4,5-dimethyl-3,5-heptanediol dibenzoate, 4,6-dimethyl-3,5-heptanediol dibenzoate, Heptanediol dibenzoate, 4,4-dimethyl-3,5-heptanediol dibenzoate, 6,6-dimethyl-3,5-heptanediol dibenzoate, 2-methyl-3-ethyl-3,5-heptanediol dibenzoate, 2-methyl-4-ethyl-3,5-heptanediol dibenzoate, 2-methyl-5-ethyl-3,5-heptanediol dibenzoate, 3-methyl-3-ethyl-3,5-heptanediol dibenzoate, 3-methyl-4-ethyl-3,5-heptanediol dibenzoate, 3-methyl-5-ethyl-3,5-heptanediol dibenzoate, 4-methyl-3-ethyl-3,5-heptanediol dibenzoate, 4-methyl-4-ethyl-3,5-heptanediol dibenzoate, 4-methyl-5-ethyl-3,at least one of 2-methyl-5-propyl-3,5-heptanediol dibenzoate, 2-methyl-3-propyl-3,5-heptanediol dibenzoate, 2-methyl-4-propyl-3,5-heptanediol dibenzoate, 2-methyl-5-propyl-3,5-heptanediol dibenzoate, 3-methyl-3-propyl-3,5-heptanediol dibenzoate, 3-methyl-4-propyl-3,5-heptanediol dibenzoate, 3-methyl-5-propyl-3,5-heptanediol dibenzoate, 4-methyl-3-propyl-3,5-heptanediol dibenzoate, 4-methyl-4-propyl-3,5-heptanediol dibenzoate and 4-methyl-5-propyl-3,5-heptanediol dibenzoate; More preferably, the diol ester compound is 2,4-pentanediol dibenzoate and / or 3,5-heptanediol dibenzoate.

5. The solid catalyst component for olefin polymerization according to claim 1, wherein The diether compound is selected from at least one of the diether compounds represented by formula (3): In formula (3), R Ⅰ , R Ⅱ , R Ⅲ , R Ⅳ , R Ⅴ and R Ⅵ The same or different, each independently selected from hydrogen, halogen atoms, C1-C 20 Straight chain alkyl, C3-C 20 Branched alkyl, C3-C 20 Cycloalkyl, C6-C 20 Aryl, C7-C 20 Arylalkyl or C7-C 20 The alkylaryl group, R Ⅰ -R Ⅵ The groups of R can be bonded to form a ring; Ⅶ and R Ⅷ The same or different, each independently selected from C1-C 20 Straight chain alkyl, C3-C 20 Branched alkyl, C3-C 20 Cycloalkyl, C6-C 20 Aryl, C7-C 20 Alkyl or C7-C 20 Aralkyl; Preferably, the diether compound is selected from 2-(2-ethylhexyl)-1,3-dimethoxypropane, 2-isopropyl-1,3-dimethoxypropane, 2-butyl-1,3-dimethoxypropane, 2-sec-butyl-1,3-dimethoxypropane, 2-cyclohexyl-1,3-dimethoxypropane, 2-phenyl-1,3-dimethoxypropane, 2-(2-phenylethyl)-1,3-dimethoxypropane, 2-(2-cyclohexylethyl)-1,3-dimethoxypropane, 2-(p-chlorophenyl)-1,3-dimethoxypropane, 2-(diphenylmethyl)-1,3-dimethoxypropane, 2,2-dicyclohexyl-1,3-dimethoxypropane, ,2-dicyclopentyl-1,3-dimethoxypropane, 2,2-diethyl-1,3-dimethoxypropane, 2,2-dipropyl-1,3-dimethoxypropane, 2,2-diisopropyl-1,3-dimethoxypropane, 2,2-dibutyl-1,3-dimethoxypropane, 2-methyl-2-propyl-1,3-dimethoxypropane, 2-methyl-2-benzyl-1,3-dimethoxypropane, 2-methyl-2-ethyl-1,3-dimethoxypropane, 2-methyl-2-isopropyl-1,3-dimethoxypropane, 2-methyl-2-phenyl-1,3-dimethoxypropane, 2, 2-bis(2-cyclohexylethyl)-1,3-dimethoxypropane, 2-methyl-2-isobutyl-1,3-dimethoxypropane, 2-methyl-2-(2-ethylhexyl)-1,3-dimethoxypropane, 2,2-diisobutyl-1,3-dimethoxypropane, 2,2-diphenyl-1,3-dimethoxypropane, 2,2-dibenzyl-1,3-dimethoxypropane, 2,2-bis(cyclohexylmethyl)-1,3-dimethoxypropane, 2-isobutyl-2-isopropyl-1,3-dimethoxypropane, 2-(1-methylbutyl)-2-isopropyl-1,3-dimethoxypropane, 2-isopropyl-2-isopentyl-1,3-dimethoxy at least one of propane, 2-phenyl-2-isopropyl-1,3-dimethoxypropane, 2-phenyl-2-sec-butyl-1,3-dimethoxypropane, 2-benzyl-2-isopropyl-1,3-dimethoxypropane, 2-cyclopentyl-2-isopropyl-1,3-dimethoxypropane, 2-cyclopentyl-2-sec-butyl-1,3-dimethoxypropane, 2-cyclohexyl-2-isopropyl-1,3-dimethoxypropane, 2-cyclohexyl-2-sec-butyl-1,3-dimethoxypropane, 2-isopropyl-2-sec-butyl-1,3-dimethoxypropane, 2-cyclohexyl-2-cyclohexylmethyl-1,3-dimethoxypropane and 9,9-dimethoxymethylfluorene; More preferably, the diether compound is 2-isopropyl-2-isopentyl-1,3-dimethoxypropane and / or 9,9-dimethoxymethylfluorene.

6. The catalyst component for olefin polymerization according to claim 1, wherein The molar ratio of the succinic acid monoester compound, the diol ester compound and the diether compound is 0.1-1.2:0.1-1.0:1, preferably 0.15-0.75:0.12-0.65:

1.

7. The catalyst component for olefin polymerization according to claim 1, wherein The magnesium source is at least one of magnesium halide, magnesium alcoholate or halogenated alcoholate and magnesium halide adduct carrier; the titanium source is a general formula Ti(OR′) 3-a Z a and Ti(OR′) 4-b Z b At least one of the compounds shown, wherein R′ is C1-C 20 The alkyl group is preferably C1-C 12 An alkyl group, more preferably a C1-C6 alkyl group, Z is a halogen, a is an integer of 1-3, and b is an integer of 1-4; Preferably, the titanium source is at least one of titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, tributoxytitanium chloride, dibutoxytitanium dichloride, butoxytitanium trichloride, triethoxytitanium chloride, diethoxytitanium dichloride, ethoxytitanium trichloride and titanium trichloride.

8. The catalyst component for olefin polymerization according to claim 1, wherein The content of magnesium element in the catalyst component is 2-16 parts by weight, preferably 3-15 parts by weight, and more preferably 4-13 parts by weight per part by weight of titanium element; the content of internal electron donor is 2-17 parts by weight, preferably 3-15 parts by weight, and more preferably 4-13 parts by weight.

9. The method for preparing a solid catalyst component for olefin polymerization according to any one of claims 1 to 8, characterized in that: The steps include: A magnesium source is contacted with a titanium source for reaction, and an internal electron donor is added in one or more time periods before, during and after the contact reaction of the magnesium source and the titanium source, and then the titanium source is treated once or multiple times, and then washed with an inert solvent to obtain the solid catalyst component.

10. The preparation method according to claim 9, wherein: The molar ratio of the magnesium source calculated as magnesium element, the titanium source calculated as titanium element and the internal electron donor is 1:12-200:0.1-1.5, preferably 1:15-180:0.15-1.

2.

11. A catalyst for olefin polymerization, characterized in that: The catalyst comprises the reaction product of: (i) the catalyst component according to any one of claims 1 to 8; (ii) at least one alkylaluminum compound; and (iii) Optional external electron donor.

12. The catalyst for olefin polymerization according to claim 11, wherein The alkyl aluminum compound is selected from the group consisting of AlR n X 3-n At least one of the compounds shown, wherein R is a C1-C8 alkyl group, the hydrogen on the alkyl group is optionally substituted by a halogen atom, X is a halogen, and n is 1, 2 or 3; Preferably, the alkylaluminum compound is selected from at least one of triethylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri-n-hexylaluminum, diethylaluminum monochloride, diisobutylaluminum monochloride, di-n-butylaluminum monochloride, di-n-hexylaluminum monochloride, monoethylaluminum dichloride, monoisobutylaluminum dichloride, mono-n-butylaluminum dichloride and mono-n-hexylaluminum dichloride.

13. The catalyst for olefin polymerization according to claim 11, wherein The external electron donor is selected from at least one of carboxylic acid, carboxylic anhydride, carboxylic ester, ketone, ether, alcohol, lactone, organophosphorus compound and organosilicon compound; preferably, the external electron donor is selected from at least one Si-OR 19 bond, and the general formula is (R 17 ) x (R 18 ) y Si(OR 19 ) z Silicon compounds, where R 17 , R 18 and R 19 C1-C 18 The hydrocarbon group optionally contains heteroatoms, x and y are each independently an integer of 0-2, z is an integer of 1-3, and the sum of x, y, and z is 4, R 17 , R 18 Preferably C3-C 10 The alkyl or cycloalkyl group may contain heteroatoms; R 19 Preferably C1-C 10 An alkyl group optionally containing heteroatoms; Preferably, the external electron donor is selected from at least one of cyclohexylmethyldimethoxysilane, diisopropyldimethoxysilane, di-n-butyldimethoxysilane, diisobutyldimethoxysilane, diphenyldimethoxysilane, methyl-tert-butyldimethoxysilane, dicyclopentyldimethoxysilane, 2-ethylpiperidinyl-2-tert-butyldimethoxysilane, (1,1,1-trifluoro-2-propyl)-2-ethylpiperidinyldimethoxysilane and (1,1,1-, trifluoro-2-propyl)-methyldimethoxysilane.

14. The catalyst for olefin polymerization according to claim 11, wherein The molar ratio of the solid catalyst component calculated as titanium element to the alkyl aluminum compound calculated as aluminum element is 1:1-2000, preferably 1:20-500, more preferably 1:30-300; the molar ratio of the external electron donor to the alkyl aluminum compound calculated as aluminum element is 1:1-300, preferably 1:2-100.

15. Use of the catalyst for olefin polymerization according to any one of claims 11 to 14 in olefin polymerization reactions.

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