Catalyst component for olefin polymerization, preparation method therefor and use thereof

Abstract

The present invention relates to an olefin polymerization catalyst. Disclosed are a catalyst component for olefin polymerization, a preparation method therefor and a use thereof. The catalyst component of the present invention comprises a magnesium element, a titanium element, a halogen and an electron donor, wherein the electron donor comprises furan compounds and diether compounds. The molecular weight distribution of a low melt index polymer prepared when the catalyst component is used for olefin polymerization is broader than that of a high melt index polymer.

Description

Catalyst component for olefin polymerization, preparation method and use thereof

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Chinese patent applications 202310721613.3 and 202310722783.3 filed on June 16, 2023, the contents of which are incorporated herein by reference. Technical Field

[0003] The present invention belongs to the field of olefin polymerization catalysts, and in particular relates to a catalyst component for olefin polymerization, a preparation method thereof and an application thereof. Background Art

[0004] As we all know, since its advent, ZN catalyst has been continuously developed and has become the main catalyst for industrial olefin polymerization reactions.

[0005] Internal electron donors driving the development of ZN catalysts have evolved from monobasic acid esters, such as ethyl benzoate and ethyl p-ethoxybenzoate, in third-generation ZN catalysts, to dibasic acid esters, such as diisobutyl phthalate, in fourth-generation ZN catalysts. Phthalate esters (plasticizers) are currently the most commonly used internal electron donors in polypropylene catalysts. However, studies have shown that they can cause serious damage to the growth, development, and reproductive systems of animals, and may also have similar effects on humans. The United States, the European Union, and other countries and regions have successively designated these compounds as toxic chemicals, placing strict restrictions on their use (particularly in infant toys). Therefore, the development of high-performance catalysts that do not contain phthalates is imperative.

[0006] High-fluidity polypropylene is one of the main development directions of polypropylene in the future due to its good processing properties. In order to obtain olefin polymers with high melt flow rate, it is generally necessary to add a large amount of hydrogen during polymerization to make the polymer low-molecular. However, the upper limit of the amount of hydrogen that can be added is limited by the pressure resistance of the polymerization reactor. In order to add more hydrogen, the partial pressure of the olefin gas to be polymerized has to be reduced, in which case productivity will decrease. At the same time, the polymers obtained by olefin polymerization catalysts in the prior art when used for olefin polymerization have the problem of insufficient processing properties of low-fluidity polymers and the problem of many precipitates of high-fluidity polymers.

[0007] Summary of the Invention

[0008] The present invention provides an olefin polymerization catalyst that, when used in olefin polymerization, narrows the molecular weight distribution of the resulting polymer as the melt index increases, thereby enabling low-melt-index polymers to have good processability and high-melt-index polymers to have low precipitates, thereby achieving both good processability and environmental friendliness. Furthermore, the catalyst component of the present invention does not contain phthalate compounds (plasticizers).

[0009] The first aspect of the present invention provides a catalyst component for olefin polymerization, which comprises magnesium, titanium, halogen and an electron donor; wherein the electron donor comprises a furan compound and a diether compound; the furan compound is selected from at least one of the furan compounds represented by formula (I),

[0010] In formula (I), R1 and R3 are each independently selected from hydrogen, C1-C 20 Straight or branched alkyl, C3-C 20 Cycloalkyl, C6-C 20 Aryl, C7-C 20 Arylalkyl or C7-C 20 R2 and R4 are each independently selected from C1-C 10 Straight or branched alkyl, C3-C 10 Cycloalkyl, C6-C 10 Aryl, C7-C 10 Arylalkyl or C7-C 10 Alkaryl.

[0011] A second aspect of the present invention provides a method for preparing a catalyst component for olefin polymerization, the method comprising: mixing a magnesium source, a titanium source, and an electron donor, wherein the electron donor comprises a furan compound and a diether compound; the furan compound is selected from at least one of the furan compounds represented by formula (I),

[0012] In formula (I), R1 and R3 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 Arylalkyl or C7-C 20 R2 and R4 are each independently selected from C1-C 10 Straight chain alkyl, C3-C 10 Branched alkyl, C3-C 10 Cycloalkyl, C6-C 10Aryl, C7-C 10 Arylalkyl or C7-C 10 Alkaryl.

[0013] A third aspect of the present invention provides a catalyst system for olefin polymerization, the catalyst system comprising:

[0014] (1) the catalyst component described in the first aspect and / or the catalyst component prepared by the method described in the second aspect;

[0015] (2) at least one aluminum alkyl; and

[0016] (3) Optional other electron donors.

[0017] The fourth aspect of the present invention provides use of the catalyst component described in the first aspect and / or the catalyst component prepared by the method described in the second aspect and / or the catalyst system described in the third aspect in olefin polymerization.

[0018] The fifth aspect of the present invention provides an olefin polymerization method, which comprises: conducting an olefin polymerization reaction in the presence of the catalyst component described in the first aspect and / or the catalyst component prepared by the method described in the second aspect and / or the catalyst system described in the third aspect.

[0019] Through the above technical solution, the present invention achieves the following beneficial effects:

[0020] (1) The present invention utilizes a furan compound represented by formula (I) and a diether compound as the electron donor catalyst component. The polymer prepared under low-hydrogen polymerization conditions has a broad molecular weight distribution, which can effectively improve the processing properties of the polymer. However, as hydrogen is added, the molecular weight distribution of the polymer prepared under high-hydrogen polymerization conditions becomes narrower, which can reduce the content of small molecules in the high melt index polymer, thereby reducing the content of precipitates. Furthermore, the high melt index product itself has good processing properties. Furthermore, the catalyst component exhibits a good balance between hydrogen sensitivity and stereospecificity when used in olefin polymerization.

[0021] (2) Preferably, the catalyst component of the present invention, which uses a magnesium-containing solid component containing sulfur as a carrier and a furan compound and a diether compound as an electron donor, has a narrow particle size distribution. When used for olefin polymerization, the catalyst component not only has a good balance between hydrogen sensitivity and stereospecificity, but also the molecular weight distribution of the prepared polymer can be narrowed with the increase of melt index, and the polymer has a low fine powder content. DETAILED DESCRIPTION

[0022] The endpoints of the ranges and any values ​​disclosed herein 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 endpoints of each range, the endpoints of each range and 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 to be specifically disclosed herein.

[0023] In the present invention, unless otherwise specified, electron donors generally refer to internal electron donors in the art, and other electron donors generally refer to external electron donors in the art.

[0024] The first aspect of the present invention provides a catalyst component for olefin polymerization, which comprises magnesium, titanium, halogen and an electron donor; wherein the electron donor comprises a furan compound and a diether compound; the furan compound is selected from at least one of the furan compounds represented by formula (I),

[0025] In formula (I), R1 and R3 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 Arylalkyl or C7-C 20 R2 and R4 are each independently selected from C1-C 10 Straight chain alkyl, C3-C 10 Branched alkyl, C3-C 10 Cycloalkyl, C6-C 10 Aryl, C7-C 10 Arylalkyl or C7-C 10 Alkaryl.

[0026] According to the present invention, in formula (I), R1 and R3 can each independently be hydrogen, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, or decyl; preferably, in formula (I), R1 and R3 are each independently selected from hydrogen, a C1-C6 straight-chain alkyl group, or a C3-C6 branched-chain alkyl group.

[0027] According to the present invention, in formula (I), R2 and R4 can each independently be methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, or decyl; preferably, in formula (I), R2 and R4 are each independently selected from a C1-C6 straight-chain alkyl group or a C3-C6 branched-chain alkyl group; more preferably, selected from a C1-C3 straight-chain alkyl group.

[0028] The inventors of the present invention unexpectedly discovered that when a diether compound is combined with a furan compound represented by formula (I) of the present application as an electron donor, a synergistic effect is achieved. When used in olefin polymerization, the molecular weight distribution of the resulting polymer narrows as the melt index increases, thereby achieving both good processability and environmental friendliness. Furthermore, the catalyst component exhibits a good balance between hydrogen sensitivity and stereospecificity.

[0029] According to the present invention, preferably, in the catalyst component, the content of the furan compound per mole of the diether compound is 0.01-2 moles; for example, in the catalyst component, the content of the furan compound per mole of the diether compound can be 0.01 mole, 0.05 mole, 0.06 mole, 0.07 mole, 0.08 mole, 0.09 mole, 0.1 mole, 0.15 mole, 0.2 mole, 0.25 mole, 0.3 mole, 0.35 mole, 0.4 mole, 0.45 mole, 0.5 mole, 0.6 mole, 0.7 mole, 0.8 mole, 0.9 mole, 1 mole, 1.1 mole, 1.2 mole, 1.5 mole, 2 moles, or ranges consisting of any two of the foregoing. More preferably, in the catalyst component, the content of the furan compound per mole of the diether compound is 0.03-1.2 moles, and even more preferably 0.05-0.4 moles. When the molar ratio of the diether compound to the furan compound in the catalyst component is within the above-mentioned further preferred range, the synergistic effect of the two electron donors is more obvious, which can further improve the hydrogen sensitivity and stereospecificity, and the molecular weight distribution of the polymer under high hydrogen conditions is narrower.

[0030] According to the present invention, preferably, based on the total weight of the electron donor, the total content of the furan compound and the diether compound in the electron donor is 70 wt%-100 wt%, more preferably 80 wt%-100 wt%, and further preferably 90-100 wt%.

[0031] According to the present invention, preferably, the furan compound is selected from at least one of the furan compounds represented by formula (I-1),

[0032] In formula (I-1), R1, R2, R3, and R4 are as described in formula (I) and are not repeated here.

[0033] According to the present invention, preferably, the furan compound is selected from at least one of (3R,3aR,6S,6aR)-3-methoxy-6-propoxyhexahydrofuro[3,2-b]furan, (3R,3aR,6S,6aR)-3-methoxy-6-ethoxyhexahydrofuro[3,2-b]furan, (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan, (3R,3aR,6S,6aR)-3,6-diethoxyhexahydrofuro[3,2-b]furan, and (3R,3aR,6S,6aR)-3,6-dipropoxyhexahydrofuro[3,2-b]furan. More preferably, the furan compound is (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan.

[0034] According to the present invention, the diether compound can 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 (II).

[0035] In formula (II), 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 may be optionally linked 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 Alkaryl or C7-C 20 of aralkyl.

[0036] According to the present invention, preferably, in formula (II), R Ⅰ 、R Ⅱ 、R Ⅲ 、R Ⅳ 、R Ⅴand R Ⅵ Each independently selected from hydrogen, C1-C 20 Straight chain alkyl, C3-C 20 branched alkyl; or, R Ⅲ 、R Ⅳ More preferably, in formula (II), R Ⅰ 、R Ⅱ 、R Ⅲ 、R Ⅳ 、R Ⅴ and R Ⅵ Each is independently selected from hydrogen, C1-C7 straight-chain alkyl, and C3-C7 branched-chain alkyl.

[0037] According to the present invention, preferably, in formula (II), R Ⅲ 、R Ⅳ When the fluorene ring is formed by bonding, the diether compound has the structure of formula (II-1),

[0038] Among them, in formula (II-1), R Ⅰ 、R Ⅱ 、R Ⅴ 、R Ⅵ 、R Ⅶ and R Ⅷ As shown in formula (II).

[0039] According to the present invention, preferably, in formula (II), R Ⅶ and R Ⅷ Each is independently selected from C1-C5 straight-chain alkyl and C3-C5 branched-chain alkyl.

[0040] According to the present invention, 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-dimethoxy 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 , 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 at least one of 9,9-bis(methoxymethyl)fluorene. More preferably, the diether compound is 2-isopropyl-2-isopentyl-1,3-dimethoxypropane and / or 9,9-bis(methoxymethyl)fluorene.

[0041] In the catalyst component of the present invention, the content of magnesium element may be 2-18 parts by weight, preferably 3-16 parts by weight, per part by weight of titanium element.

[0042] In the catalyst component of the present invention, the content of the electron donor can be 2-17 parts by weight, preferably 3-15 parts by weight, calculated per part by weight of titanium element.

[0043] According to the present invention, the catalyst component may further contain a halogen. The halogen in the catalyst component may be at least one of fluorine, chlorine, bromine, and iodine. The source of the halogen in the catalyst component may be a halogen contained in a source of magnesium and / or a source of titanium.

[0044] According to the present invention, the source of the magnesium element can be any magnesium-containing compound that can be used to prepare a polyolefin catalyst component; preferably, the source of the magnesium element is selected from at least one of magnesium halides (e.g., magnesium chloride and / or magnesium bromide), magnesium alcoholates (e.g., diethoxymagnesium), magnesium halogenated alcoholates (e.g., ethoxymagnesium chloride), magnesium halide alcohol adducts, magnesium halide adducts (e.g., magnesium halide adducts disclosed in patent applications CN1091748, CN101050245, CN101486722, CN102796132B, CN102796129B, and CN102796128B, and the relevant contents disclosed in these patent applications are all incorporated herein by reference) and magnesium-containing solid components.

[0045] In the present invention, the magnesium halide alcohol adduct may be, for example, at least one of the structures shown in formula (IV); MgX2·m'R7OH Formula (IV)

[0046] In formula (IV), X is a halogen, preferably chlorine or bromine; m' is 1-5; and R7 is a C1-C6 straight-chain or branched alkyl group, such as methyl, ethyl, propyl, butyl, pentyl, or hexyl.

[0047] In the present invention, the magnesium-containing solid component may be, for example, at least one of the structures represented by formula (III);

[0048] In formula (III), R1 is a C1-C6 straight chain or branched alkyl group; R2 and R3 are the same or different and are independently hydrogen or a C1-C5 straight chain or branched alkyl group, wherein the hydrogen on the alkyl group may be optionally replaced by a halogen atom; X is a halogen, preferably chlorine or bromine; m is 0.1-1.9, n is 0.1-1.9, m+n=2, 0 <q≤0.5。

[0049] According to the present invention, preferably, the average particle diameter of the magnesium-containing solid component is 12-30 microns, and the particle size distribution is less than 1.2, more preferably 0.2-0.8. In the present invention, the average particle diameter and particle size distribution of the olefin polymerization catalyst support (magnesium-containing solid component) can be measured using a Master Sizer 2000 laser particle size analyzer (manufactured by Malvern Instruments Ltd).

[0050] The magnesium-containing solid component synthesis raw material contains a sulfur source, a general formula of MgX 2 Y magnesium halide, compound of general formula R4OH, ethylene oxide compound; in general formula MgX 2 In Y, X 2 is halogen, Y is halogen or C1-C6 alkyl, C1-C5 alkoxy, C6-C 10 Aryl or C6-C 10 In the general formula R4OH, R4 is a C1-C8 alkyl group or a C3-C8 cycloalkyl group; the structure of the oxirane compound is shown in formula (V):

[0051] In formula (V), R5 and R6 are each independently hydrogen, C1-C5 alkyl or C1-C5 haloalkyl.

[0052] According to the present invention, the sulfur source is anhydrous sulfur or sulfur containing crystal water, sulfur or sulfur bromide, sulfur chloride or sulfur iodide, preferably sulfur and / or sulfur chloride; more preferably α-sulfur and / or β-sulfur.

[0053] According to the present invention, in the general formula MgX 2 In Y, X 2 Preferably, chlorine or bromine, Y is preferably chlorine, bromine, C1-C5 alkyl, C1-C5 alkoxy, C6-C 10 Aryl or C6-C 10 The C1-C5 alkyl group may be, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl or neopentyl; the C1-C5 alkoxy group may be, for example, methoxy, ethoxy, propoxy, isopropoxy, butoxy or isobutoxy; the C6-C 10 The aryl group may be, for example, phenyl, o-tolyl, m-tolyl, p-tolyl, o-ethylphenyl, m-ethylphenyl, p-ethylphenyl or naphthyl. 10 The aryloxy group may be, for example, a phenoxy group or a naphthoxy group.

[0054] The general formula is MgX 2 The magnesium halide of Y can be a single magnesium halide or a mixture of multiple magnesium halides. 2Specific examples of the magnesium halide of Y may include, but are not limited to, one or more of magnesium chloride, magnesium bromide, phenoxymagnesium chloride, isopropoxymagnesium chloride, and n-butoxymagnesium chloride. Magnesium chloride is preferred from the perspective of raw material availability.

[0055] According to the present invention, in the general formula R4OH, R4 is preferably a C1-C8 alkyl group; the C1-C8 alkyl group may be, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, hexyl, isohexyl, heptyl, isoheptyl, octyl, or isooctyl. Specific examples of the compound of the general formula R4OH may include, but are not limited to, one or more of ethanol, propanol, isopropanol, n-butanol, isobutanol, amyl alcohol, isopentanol, n-hexanol, n-octanol, and 2-ethylhexanol.

[0056] According to the present invention, in the oxirane compound represented by formula (V), R5 and R6 are preferably each independently hydrogen, a C1-C3 alkyl group, or a C1-C3 haloalkyl group. Specific examples of the oxirane compound may include, but are not limited to, one or more of ethylene oxide, propylene oxide, butylene oxide, epichlorohydrin, epichlorobutane, epibromohydrin, and epibromobutane.

[0057] According to the present invention, the water contained in the magnesium-containing solid component comes from trace water in the synthesis raw materials and the reaction medium.

[0058] The method for preparing the magnesium-containing solid component of the present invention comprises the following steps:

[0059] (a) a sulfur source, a general formula of MgX 2 A magnesium halide of Y, a compound of the general formula R4OH, and an optional inert liquid medium are mixed and heated to obtain a liquid mixture;

[0060] (b) emulsifying the liquid mixture obtained in step (a), and contacting the emulsified product with an oxirane compound for reaction.

[0061] In the general formula MgX 2 In Y, X 2 is halogen, Y is halogen or C1-C6 alkyl; in the general formula R4OH, R4 is C1-C8 alkyl or C3-C8 cycloalkyl; the structure of the oxirane compound is shown in formula (V):

[0062] Among them, the general formula is MgX 2 The types of magnesium halide Y, compound of the general formula R4OH, sulfur source, and ethylene oxide compound have been described above and will not be repeated here.

[0063] According to the present invention, wherein 1 mol of the general formula MgX 2 The amount of the sulfur source is 0.0001-0.1 mol, the amount of the compound of the general formula R4OH is 4-30 mol, and the amount of the ethylene oxide compound of the structure shown in formula (V) is 1-10 mol; preferably, 1 mol of the general formula MgX 2 Based on the magnesium halide of Y, the amount of the compound with the general formula R4OH is 6-20 mol, and the amount of the ethylene oxide compound with the structure shown in formula (V) is 2-6 mol.

[0064] According to the present invention, a trace amount of water in the above-mentioned reactants can also participate in the reaction of forming the magnesium-containing solid component.

[0065] According to the present invention, a surfactant can be added to the liquid mixture described in step (a), and the surfactant is selected from the group consisting of polyvinyl pyrrolidone (PVP), polyethylene glycol (PEG), polyacrylic acid, polyacrylate, polystyrene sulfonate, naphthalenesulfonic acid formaldehyde condensate, condensed alkyl phenyl ether sulfate, condensed alkylphenol polyoxyethylene ether phosphate, oxyalkyl acrylate copolymer modified polyethyleneimine, 1-dodecan-4-vinylpyridinium bromide polymer, polyvinyl benzyltrimethylamine salt, polyvinyl alcohol, polyacrylamide, polyethylene oxide propylene oxide block copolymer, polyvinyl pyrrolidone vinyl acetate copolymer, alkylphenyl polyoxyethylene ether and polyalkyl methacrylate compounds, or a combination thereof, preferably polyvinyl pyrrolidone, polyvinyl pyrrolidone vinyl acetate copolymer and polyethylene glycol, or a combination thereof.

[0066] According to the present invention, in step (a), for the sulfur source, the general formula MgX 2 The conditions for heating the mixture of the magnesium halide of Y, the compound of the general formula R4OH, and optionally the inert liquid medium are not particularly limited, as long as the heating conditions can make the general formula MgX 2 The magnesium halide of Y is melted and fully reacted with the sulfur source. Generally, the heating conditions include: a temperature of 80-120°C and a heating time of 0.5-5 hours; preferably, the heating temperature is 80-100°C and the heating time is 0.5-3 hours.

[0067] According to the present invention, the amount of the inert liquid medium can be determined according to the general formula: MgX 2 The amount of magnesium halide Y is selected. Generally, 1 mol of the general formula is MgX 2The amount of the inert liquid medium can be 0.8-10 L, preferably 2-8 L, based on the magnesium halide of Y. The inert liquid medium can be any liquid medium that does not chemically interact with the reactants and reaction products commonly used in this area. For example, the inert liquid medium can be silicone oil and / or an inert liquid hydrocarbon solvent. Specifically, the inert liquid medium can be one or more of kerosene, paraffin oil, vaseline, white oil, methyl silicone oil, ethyl silicone oil, methylethyl silicone oil, phenyl silicone oil and methylphenyl silicone oil. The inert liquid medium of the present invention is particularly preferably white oil.

[0068] According to the present invention, the liquid mixture obtained in step (a) can be emulsified using various methods known to those skilled in the art. For example, the liquid mixture can be emulsified by subjecting it to low-speed shearing or high-speed shearing. The stirring rate of the low-speed shearing is generally 400-800 rpm. The high-speed shearing method is well known to those skilled in the art, such as the high-speed stirring method disclosed in CN1151183C (i.e., stirring the solution containing the liquid magnesium halide adduct at a speed of 2000-5000 rpm). In addition, the liquid mixture can also be emulsified with reference to the methods disclosed in the following patents: CN1267508C discloses that a solution containing a liquid magnesium halide adduct is subjected to rotational dispersion in a supergravity bed (the rotation speed may be 100-3000 rpm); CN1463990A discloses that a solution containing a liquid magnesium halide adduct is output in an emulsifier at a speed of 1500-8000 rpm; US6020279 discloses that a solution containing a liquid magnesium halide adduct is emulsified by a spray method.

[0069] According to the present invention, in step (b), the conditions for the contact reaction of the emulsified product with the ethylene oxide compound can be various existing conditions that can form an olefin polymerization catalyst support. For example, the contact reaction conditions include a temperature of 50-120°C and a time of 20-60 minutes; preferably, the temperature is 60-100°C and the time is 20-50 minutes.

[0070] According to the present invention, in step (b), the method may further include performing solid-liquid separation on the product obtained by the contact reaction, washing the solid phase product and drying it. The solid-liquid separation may be any of the existing methods capable of achieving separation of the solid phase and the liquid phase, such as suction filtration, filter press or centrifugal separation. Preferably, the solid-liquid separation method is filter press. The present invention does not particularly limit the conditions for filter press, so as to achieve the separation of the solid phase and the liquid phase as fully as possible. The washing may be performed by methods well known to those skilled in the art, for example, the solid phase product may be washed with an inert hydrocarbon solvent (for example, pentane, hexane, heptane, petroleum ether and gasoline). The present invention does not particularly limit the conditions for the drying, for example, the drying temperature may be 20-70°C, and the drying time may be 0.5-10 hours. According to the present invention, the drying may be performed under normal pressure or reduced pressure.

[0071] Preferably, the magnesium-containing solid component particles obtained in the above process of preparing the magnesium-containing solid component are washed with an inert hydrocarbon solvent (such as hexane, heptane, octane, decane, toluene, etc.) and dried before being used in the subsequent step to prepare the catalyst component for olefin polymerization.

[0072] According to the present invention, the source of the titanium element can be any titanium-containing compound capable of preparing a polyolefin catalyst component; preferably, the source of the titanium element is selected from the group consisting of compounds having the general formula Ti(OR′) 3-a Z a and / or Ti(OR′) 4-b Z b A titanium compound wherein R′ is C1-C 20 Alkyl, preferably C1-C 14 wherein the titanium element is an aliphatic hydrocarbon group, preferably a C1-C8 alkyl group, such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, etc.; Z is F, Cl, Br, or I; a is an integer of 1-3; b is an integer of 0-4, preferably an integer of 1-4. More preferably, the source of the titanium element is selected from 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.

[0073] According to a specific embodiment of the present invention, the present invention also provides a catalyst component for olefin polymerization, wherein the catalyst component comprises a reaction product of the following components: a magnesium source, a titanium source and an electron donor, wherein the electron donor comprises a furan compound and a diether compound.

[0074] According to a specific embodiment of the present invention, the present invention also provides a catalyst component for olefin polymerization, which comprises the reaction product of the following components:

[0075] (1) a magnesium-containing solid component;

[0076] (2) at least one titanium-containing compound (titanium source); and

[0077] (3) electron donor;

[0078] The electron donor contains a furan compound and a diether compound; and the magnesium-containing solid component is at least one of the structures represented by formula (III).

[0079] A second aspect of the present invention provides a method for preparing a catalyst component for olefin polymerization, the method comprising: mixing a magnesium source, a titanium source, and an electron donor, wherein the electron donor comprises a furan compound and a diether compound; the furan compound is selected from at least one of the furan compounds represented by formula (I),

[0080] In formula (I), R1 and R3 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 Arylalkyl or C7-C 20 R2 and R4 are each independently selected from C1-C 10 Straight chain alkyl, C3-C 10 Branched alkyl, C3-C 10 Cycloalkyl, C6-C 10 Aryl, C7-C 10 Arylalkyl or C7-C 10 Alkaryl.

[0081] The catalyst component for olefin polymerization of the present invention can be prepared by conventional methods. For example, the mixing method includes: contacting a magnesium source with a titanium source, and adding an electron donor in one or more time periods before, during, and after the contact reaction of the magnesium source and the titanium source. The components of the electron donor can be added separately or simultaneously. The electron donor comprises a furan compound and a diether compound. Specifically, the reaction of the magnesium source and the titanium source can be carried out in the same manner as in the prior art. For example, the titanium source can be cooled to below 0°C (preferably -5 to -30°C), then the magnesium source is added, and stirred and mixed at this temperature for 10-60 minutes, then the temperature is raised to the reaction temperature (i.e., about 60-130°C), and maintained at the reaction temperature for 0.5-10 hours, preferably 0.5-5 hours. 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.

[0082] According to a particularly preferred embodiment of the present invention, a method for preparing a catalyst component for olefin polymerization comprises: adding a titanium source (e.g., a titanium halide) to a reaction vessel, cooling to -30°C to 0°C, then adding a magnesium source to the reaction vessel, and stirring and mixing at this temperature for 10-60 minutes; then heating to 0-130°C (preferably 80°C-130°C), adding an electron donor during the heating process, and then maintaining the temperature at 0-130°C (preferably 80°C-130°C) for 10-900 minutes (preferably 20-240 minutes) after filtering off the liquid. Then, adding a titanium source (e.g., a titanium halide) for washing, then washing with a non-polar solvent (e.g., hexane), and drying to obtain the catalyst component.

[0083] In the present invention, the types of furan compounds and diether compounds used in the method for preparing the catalyst component for olefin polymerization are as described in the first aspect and will not be repeated here.

[0084] In the present invention, the types of magnesium source and titanium source used in the method for preparing the catalyst component for olefin polymerization are the same as those described for the source of magnesium and titanium in the first aspect, and will not be repeated here.

[0085] According to the present invention, in the method for preparing a catalyst component for olefin polymerization, the amount of the furan compound used per mole of the diether compound can be 0.1-3 moles. For example, the amount of the furan compound used per mole of the diether compound can be 0.1 mole, 0.2 mole, 0.3 mole, 0.4 mole, 0.5 mole, 0.6 mole, 0.7 mole, 0.8 mole, 0.9 mole, 1 mole, 1.1 mole, 1.2 moles, 1.3 moles, 1.4 moles, 1.5 moles, 1.6 moles, 1.7 moles, 1.8 moles, 1.9 moles, 2 moles, 2.1 moles, 2.5 moles, 3 moles, or ranges consisting of any two of the foregoing. Preferably, the amount of the furan compound used per mole of the diether compound is 0.1-2 moles, more preferably 0.15-1.8 moles. When the molar ratio of the diether compound to the furan compound in the catalyst component is within the preferred range, the synergistic effect of the two electron donors is more pronounced, further improving hydrogen sensitivity and stereospecificity, and yielding a polymer with a higher melt index and a narrower molecular weight distribution. The furan compound can also be used in an amount of 0.1-1.5 mol, 0.15-1.5 mol, 0.15-1.2 mol, 0.15-1 mol, or 0.2-1 mol per mol of the diether compound.

[0086] In the method for preparing a catalyst component for olefin polymerization of the present invention, the molar ratio of the magnesium source calculated as magnesium element to the titanium source calculated as titanium element can be 1:5, 1:15, 1:20, 1:25, 1:30, 1:35, 1:40, 1:45, 1:50, 1:60, 1:70, 1:80, 1:90, 1:100, 1:110, 1:120, 1:130, 1:140, 1:150, 1:160, 1:170, 1:180, 1:200, 1:220, or any range consisting of any two of the above. Preferably, in the method for preparing a catalyst component for olefin polymerization, the molar ratio of the magnesium source calculated as magnesium element to the titanium source calculated as titanium element is 1:5-220, more preferably 1:15-180, and even more preferably 1:18-150.

[0087] In the method for preparing a catalyst component for olefin polymerization of the present invention, the molar ratio of the magnesium source to the electron donor, calculated as magnesium element, can be 1:0.05, 1:0.1, 1:0.15, 1:0.2, 1:0.25, 1:0.3, 1:0.35, 1:0.4, 1:0.45, 1:0.5, 1:0.55, 1:0.6, 1:0.65, 1:0.7, 1:0.75, 1:0.8, 1:0.85, 1:0.9, 1:0.95, 1:1, 1:1.2, or any range consisting of any two of the above. Preferably, in the method for preparing a catalyst component for olefin polymerization, the molar ratio of the magnesium source to the electron donor, calculated as magnesium element, is 1:0.05-1.2, more preferably 1:0.1-1, and even more preferably 1:0.15-0.9.

[0088] According to the present invention, preferably, in the method for preparing the catalyst component for olefin polymerization, the molar ratio of the magnesium source calculated as magnesium element, the titanium source calculated as titanium element and the electron donor is 1:15-180:0.1-1, more preferably 1:18-150:0.15-0.9.

[0089] According to one embodiment of the present invention, a method for preparing a catalyst component for olefin polymerization is provided, comprising: contacting a magnesium-containing solid component with a titanium compound for reaction, and adding an electron donor comprising a furan compound and a diether compound. During the preparation of the catalyst component of the present invention, the titanium compound may be used in an amount of 5-220 mol, preferably 10-200 mol, per mol of magnesium; and the electron donor may be used in an amount of 0.05-1.2 mol, preferably 0.07-1.0 mol, and more preferably 0.1-0.8 mol, per mol of magnesium.

[0090] A third aspect of the present invention provides a catalyst system for olefin polymerization, the catalyst system comprising:

[0091] (1) The catalyst component described in the first aspect and / or the catalyst component prepared by the method described in the second aspect;

[0092] (2) At least one alkylaluminum; and

[0093] (3) Optional other electron donors.

[0094] According to the present invention, the amount of the alkylaluminum used can be a conventional amount in the art. Preferably, the molar ratio of the alkylaluminum in terms of aluminum element to the catalyst component in terms of titanium element is 1 - 2000:1, more preferably 20 - 500:1, and further preferably 30 - 300:1.

[0095] According to the present invention, the amount of the other electron donor used can be a conventional amount in the art. Preferably, the molar ratio of the other electron donor to the alkylaluminum compound in terms of aluminum element is 1:1 - 300, more preferably 1:2 - 100.

[0096] According to the present invention, the alkylaluminum can be various alkylaluminums conventionally used in the art. For example, the general formula of the alkylaluminum can be AlR″ n1 X′ 3-n1 , where R″ is an alkyl group of C1 - C8, the hydrogen on the alkyl group is optionally substituted by a halogen atom, X′ is a halogen, and n1 is an integer of 0 < n1 ≤ 3. Specific examples of the C1 - C8 alkyl group can include, but are not limited to: methyl, ethyl, propyl, n - butyl, isobutyl, pentyl, hexyl, n - heptyl, n - octyl, and the halogen can be fluorine, chlorine, bromine, iodine.

[0097] According to the present invention, preferably, the alkylaluminum is selected from one or more of triethylaluminum, triisobutylaluminum, tri - n - butylaluminum, tri - n - hexylaluminum, monochlorodiethylaluminum, monochlorodiisobutylaluminum, monochlorodi - n - butylaluminum, monochlorodi - n - hexylaluminum, dichloroethylaluminum, dichloroisobutylaluminum, dichloro - n - butylaluminum, and dichloro - n - hexylaluminum.

[0098] According to the present invention, the other electron donor can be various external electron donors commonly used in the art. For example, the other 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.

[0099] Preferably, the other electron donor is selected from a silicon compound containing at least one Si - OR 19 bond and having a general formula of (R 17 ) x (R 18 ) y Si(OR 19 ) z , where R17 、R 18 and R 19 Each independently is C1-C 18 A hydrocarbon group optionally containing 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 Alkyl, C3-C 10 The cycloalkyl group optionally contains heteroatoms; R 19 Preferably C1-C 10 alkyl, optionally containing heteroatoms. More preferably, the other electron donors are 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.

[0100] According to the present invention, in the preparation process of the catalyst system for olefin polymerization, the alkyl aluminum compound and the optional other electron donor can be mixed with the catalyst components for olefin polymerization separately and then reacted, or the alkyl aluminum compound and the optional other electron donor can be mixed first and then mixed with the catalyst components for olefin polymerization and reacted.

[0101] The fourth aspect of the present invention provides use of the catalyst component described in the first aspect and / or the catalyst component prepared by the method described in the second aspect and / or the catalyst system described in the third aspect in olefin polymerization.

[0102] When the catalyst system of the present invention is used in an olefin polymerization reaction, the catalyst components, aluminum alkyl, and optional other electron donors can be added to the polymerization reactor separately, mixed, or prepolymerized using a prepolymerization method known in the industry before being added to the polymerization reactor. According to a preferred embodiment of the present invention, after the catalyst components, aluminum alkyl, and optional other electron donors are pre-contacted, the catalyst is preferably prepolymerized with propylene and / or other α-olefin monomers before polymerization. The prepolymerization temperature can be 5-40°C, preferably 10-30°C.

[0103] In the present invention, the specific type of olefin, the polymerization method and conditions of olefin can be conventionally selected according to the existing technology.

[0104] The fifth aspect of the present invention provides an olefin polymerization method, which comprises: conducting an olefin polymerization reaction in the presence of the catalyst component described in the first aspect and / or the catalyst component prepared by the method described in the second aspect and / or the catalyst system described in the third aspect.

[0105] According to the present invention, preferably, the olefin is selected from at least one compound represented by the formula CH2=CHR"', wherein R"' is hydrogen, C1-C6 alkyl, C6-C 12 of aromatic groups.

[0106] According to the present invention, the olefin polymerization reaction can be carried out according to existing methods, specifically, under the protection of an inert gas, in a liquid monomer or an inert solvent containing the polymerizable monomer, in the gas phase, or through a combined polymerization process in the 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 atmospheric pressure or higher, for example, 0.01-10 MPa, preferably 0.01-5 MPa, and more preferably 0.1-4 MPa. The pressure in the present invention refers to gauge pressure. During the polymerization process, hydrogen can be added to the reaction system as a polymer molecular weight regulator to adjust the molecular weight and melt index of the polymer. In addition, the types and amounts of the inert gas and solvent used in the olefin polymerization reaction are well known to those skilled in the art and will not be elaborated here. According to the present invention, before the polymerization reaction, the catalyst components and the olefin can also be prepolymerized; the temperature of the prepolymerization reaction is 5-40°C, preferably 10-30°C.

[0107] Parameters not limited in the present invention are all conventional technical means in this field.

[0108] The present invention will be described in detail below through examples.

[0109] Unless otherwise specified, the raw materials used in the examples and comparative examples are all disclosed in the prior art, for example, they can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0110] The titanium content in the catalyst component of the present invention can be measured by colorimetry. Specifically, 0.2-0.5 g of a sample is dissolved in 50 mL of 2N H2SO4, the supernatant is filtered, and the clear solution is used for colorimetry. A 2N H2SO4 solution is used as a blank in a 1 cm thick cuvette at a wavelength of 410 μm, and the absorbance E1 is measured. Then, one drop of 30 wt% H2O2 is added, shaken, and the absorbance E2 is measured. The titanium content (%) is calculated according to the following formula:

[0111] Ti%=[(E2-E1)×100) / (K·L·W·100)]×100%

[0112] Where: W is sample weight (g); L is cuvette thickness (cm); K is specific extinction coefficient (K=15.52); E1 is blank absorbance; E2 is sample absorbance.

[0113] The magnesium content in the catalyst component of the present invention can be measured according to the EDTA titration method. Specifically, take 0.2-0.5g of sample into a 250mL conical flask, add 20-30mL 2N H2SO4 solution to dissolve, add 20mL triethanolamine (1+2) standard solution, adjust pH to 10 with 20 wt% NaOH solution, shake, add 10mL pH=10 buffer solution, add 6 drops of 30% H2O2 and 30-50mL distilled water, add a small amount of chrome black T indicator, shake well, and titrate with 0.02NEDTA solution until the color changes from purple-red to blue (the purple light disappears) as the end point. The magnesium content Mg(%) is calculated according to the following formula: Mg(%)=[(VE·NE×24.31) / (G·1000)]×100%

[0114] Where: G is the mass of the sample (g); VE is the amount of EDTA consumed (mL); NE is the equivalent number of EDTA solution; 24.31 is the atomic weight of magnesium.

[0115] In the present invention, the catalyst component is weighed, dissolved in methanol, and then filtered through a membrane to test the content of furan compounds in the catalyst component. The content of furan compounds in the catalyst component of the present invention is tested using an Agilent 7890A-5975C gas chromatograph-mass spectrometer. Chromatographic conditions: HP-5 MS UI gas chromatograph column (30m×0.25mm×0.25μm), programmed temperature, hold at 35°C for 3 minutes, increase to 250°C at a rate of 10°C / min, and hold for 3 minutes. Carrier gas He, flow rate 1.0mL / min, split injection, split ratio 50:1, injection port temperature 250°C, transfer line temperature 250°C. Mass spectrometry conditions: quadrupole mass spectrometer, EI ionization source, electron energy 70eV, source temperature 200°C, full scan acquisition mode, mass range m / z 20-400.

[0116] In the present invention, the catalyst component is weighed, hydrolyzed with dilute hydrochloric acid, extracted with cyclohexane, and then the content of the diether compound in the catalyst component is measured. The content of the diether compound in the catalyst component of the present invention is measured using an Agilent 7890 gas chromatograph. The chromatographic column is: HP-INNO WAX (60m×0.530mm×1μm), and the internal standard method is: amyl ester.

[0117] The molecular weight distribution (Mw / Mn) of the polymers of the present invention was measured using a PL-GPC220 gel permeation chromatograph manufactured by Polymer Laboratories, UK, using trichlorobenzene as the solvent, a test temperature of 150°C, polystyrene as the standard, a flow rate of 1.0 mL / min, and a 3×Plgel 10 mMlXED-B 300×7.5 nm column.

[0118] The polymer melt index in the present invention is measured according to GB3682-2000 at 230° C. and a load of 2.16 kg.

[0119] The isotactic index of the polymer in the present invention is determined by the heptane extraction method.

[0120] The average particle diameter and particle size distribution of the catalyst components and their carriers in the present invention were measured using a Masters Sizer 2000 particle size analyzer (manufactured by Malvern Instruments Ltd);

[0121] The fine powder content of the polymer in the present invention is tested using a MICROTRAC MRB camsizer P4. The data in the table are the polymer content with a mesh size of less than 100 after sieving using a standard sieve, that is, the polymer content that can pass through a sieve with an aperture of 150 μm.

[0122] The following Example A is used to illustrate the preparation method of a catalyst component using an alcohol adduct of magnesium halide as a carrier and a furan compound and a diether compound as electron donors and the process of preparing a polymer.

[0123] Example 1A

[0124] (1) Preparation of catalyst components

[0125] A 300 mL glass reaction bottle was filled with 90 mL of titanium tetrachloride and cooled to -20°C. A carrier (38 mmol, calculated as magnesium element) of a magnesium dichloride alcohol adduct (structural formula: MgCl2·2.6C2H5OH) was added and stirred at this temperature for 40 minutes. The temperature was then raised to 112°C. During this heating period, 2.6 mmol of (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan and 8 mmol of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were added. The reaction mixture was maintained at 110°C for 30 minutes. The liquid was filtered, washed with titanium tetrachloride and then with hexane, and dried under vacuum to obtain catalyst component Cat-1A for olefin polymerization. The molar ratio of furan compound to diether compound in the catalyst component is shown in Table 1. The catalyst component Cat-1A was tested to have a magnesium content of 5.65 parts by weight and an electron donor content of 5.55 parts by weight per part by weight of titanium.

[0126] (2) Propylene liquid phase bulk polymerization

[0127] Liquid-phase bulk polymerization of propylene was carried out in a 5L stainless steel autoclave. Under nitrogen, 2mL of a 0.5mmol / mL hexane solution of triethylaluminum, 0.4mL of a 0.1mmol / mL hexane solution of cyclohexylmethyldimethoxysilane (CHMMS), and 9mg of the aforementioned olefin polymerization catalyst component, Cat-1A, were added to the autoclave. The autoclave was closed, and hydrogen (the amount of hydrogen is shown in Table 1) and 2.3L of liquid propylene were added. The temperature was raised to 70°C, and the reaction was allowed to proceed for 1 hour. The temperature was then lowered, the pressure was released, and the product was discharged. The resulting propylene homopolymer was dried, weighed, and analyzed. The results are shown in Table 1.

[0128] Example 2A

[0129] A catalyst component was prepared and liquid-phase bulk polymerization of propylene was carried out according to the method of Example 1A, except that 2-isopropyl-2-isopentyl-1,3-dimethoxypropane was not added during the heating process. Instead, 5 mmol of (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan and 7.5 mmol of 9,9-bis(methoxymethyl)fluorene were added to obtain a catalyst component Cat-2A for olefin polymerization. Testing of the catalyst component Cat-2A revealed that, per part by weight of titanium, the magnesium content was 5.22 parts by weight, and the electron donor content was 5.63 parts by weight.

[0130] Example 3A

[0131] A catalyst component was prepared and liquid-phase bulk polymerization of propylene was carried out according to the method of Example 1A, except that 7 mmol of (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan and 6 mmol of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were added during the heating process to obtain catalyst component Cat-3A for olefin polymerization. Testing of catalyst component Cat-3A revealed that, per part by weight of titanium, the magnesium content was 5.20 parts by weight, and the electron donor content was 4.71 parts by weight.

[0132] Example 4A

[0133] A catalyst component was prepared and liquid-phase bulk polymerization of propylene was carried out according to the method of Example 1A, except that 2 mmol of (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan and 8 mmol of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were added during the heating process to obtain catalyst component Cat-4A for olefin polymerization. Testing of catalyst component Cat-4A revealed that, based on part weight of titanium, the magnesium content was 5.74 parts by weight, and the electron donor content was 5.48 parts by weight.

[0134] Example 5A

[0135] A catalyst component was prepared and liquid-phase bulk polymerization of propylene was carried out according to the method of Example 1A, except that 8.7 mmol of (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan and 3.2 mmol of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were added during the heating process to obtain catalyst component Cat-5A for olefin polymerization. Testing of catalyst component Cat-5A revealed that, per part by weight of titanium, the magnesium content was 4.67 parts by weight, and the electron donor content was 3.62 parts by weight.

[0136] Example 6A

[0137] (1) Preparation of catalyst components

[0138] A 300 mL glass reaction bottle was charged with 80 mL of titanium tetrachloride and cooled to -15°C. 38 mmol of a magnesium dichloride alcohol adduct (structural formula: MgCl2·2.6C2H5OH) was added as a support, calculated as magnesium. The mixture was stirred at this temperature for 30 minutes, then heated to 115°C. During this heating process, 3 mmol of (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan and 8.2 mmol of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were added. The reaction mixture was maintained at 115°C for 45 minutes, after which the liquid was filtered and washed with titanium tetrachloride and then with hexane. After vacuum drying, the catalyst component Cat-6A for olefin polymerization was obtained. Testing revealed that the magnesium content of the catalyst component Cat-6A was 6.19 parts by weight, and the electron donor content was 6.63 parts by weight, per part by weight of titanium.

[0139] (2) Liquid phase bulk polymerization of propylene was the same as in Example 1A.

[0140] Comparative Example 1A

[0141] A catalyst component was prepared and propylene liquid-phase bulk polymerization was carried out according to the method of Example 1A, except that during the preparation of the catalyst component, (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan was not added, and only 11 mmol of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane was added to obtain a catalyst component DCat-1A for olefin polymerization.

[0142] Comparative Example 2A

[0143] A catalyst component was prepared and propylene liquid-phase bulk polymerization was carried out according to the method of Example 1A, except that during the preparation of the catalyst component, 2-isopropyl-2-isopentyl-1,3-dimethoxypropane was not added, and only 11 mmol of (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan was added to obtain a catalyst component DCat-2A for olefin polymerization.

[0144] Comparative Example 3A

[0145] The catalyst component was prepared and propylene liquid-phase bulk polymerization was carried out according to the method of Example 1A, except that during the preparation of the catalyst component, 2-isopropyl-2-isopentyl-1,3-dimethoxypropane was replaced with an equimolar amount of 4-ethyl-3,5-heptanediol dibenzoate to obtain a catalyst component DCat-3A for olefin polymerization.

[0146] Table 1

[0147] Note: n 呋喃：二醚 It represents the molar ratio of furan compounds to diether compounds.

[0148] As can be seen from Table 1, when the electron donor contains a certain proportion of furan compounds and diether compounds, the catalyst has high hydrogen modulation sensitivity and stereospecificity, and its balance is good. In addition, the molecular weight distribution of the prepared low melt index polymer is wider than that of the high melt index polymer. In addition, the catalyst component of the present invention does not contain phthalate compounds (plasticizers).

[0149] The following Preparation Examples and Example B are used to illustrate the preparation method of a catalyst component using a magnesium-containing solid component as a carrier and a furan compound and a diether compound as electron donors, and the process of preparing a polymer.

[0150] Preparation Example 1 Magnesium-containing solid component (catalyst support)

[0151] This preparation example is used to illustrate the olefin polymerization catalyst carrier and the preparation method thereof provided by the present invention.

[0152] In a 0.6L reactor, 0.08 mol of magnesium chloride, 0.96 mol of ethanol, 1 g of α-sulfur, and 0.5 g of PVP (polyvinylpyrrolidone) as a surfactant were added and the mixture was heated to 90°C with stirring. After a 2-hour isothermal reaction, 0.48 mol of epichlorohydrin was added. After a half-hour reaction, the mixture was filtered and washed five times with hexane and dried in vacuo to obtain the catalyst support Z1 for olefin polymerization.

[0153] The average particle diameter (D50) of the olefin polymerization catalyst support Z1 was 15 microns, and the particle size distribution ((D90-D10) / D50) was 0.6. Observation under an optical microscope revealed that the particles of the olefin polymerization catalyst support Z1 were relatively regular, smooth, and essentially spherical. The particle size distribution was relatively concentrated, and there were essentially no irregularly shaped particles.

[0154] According to GC-MS, elemental analysis and NMR characterization, the structural formula of Z1 is:

[0155] Preparation Example 2: Magnesium-containing solid component (catalyst support)

[0156] This preparation example is used to illustrate the olefin polymerization catalyst carrier and the preparation method thereof provided by the present invention.

[0157] In a 0.6L reactor, 300mL of white oil, 0.08mol of magnesium chloride, 0.48mol of ethanol, 0.3g of β-sulfur, and 1g of PVP (polyvinylpyrrolidone) as a surfactant were added and heated to 100°C with stirring. After 1 hour of isothermal reaction, 0.16mol of epichlorohydrin was added. The reaction was continued at 100°C for 20 minutes before filter pressing. The filter press product was washed five times with hexane and finally vacuum dried to obtain olefin polymerization catalyst support Z2.

[0158] The average particle diameter (D50) of the olefin polymerization catalyst support Z2 was 18 microns, and the particle size distribution ((D90-D10) / D50) was 0.7. Observation under an optical microscope revealed that the particles of the olefin polymerization catalyst support Z2 were relatively regular, smooth, and essentially spherical. The particle size distribution was relatively concentrated, and there were essentially no irregularly shaped particles.

[0159] According to GC-MS, elemental analysis and NMR characterization, the structural formula of Z2 is:

[0160] Example 1B

[0161] (1) Preparation of catalyst components

[0162] In a 300 mL glass reaction bottle, 80 mL of titanium tetrachloride was added, the mixture was cooled to -20°C, and 8 g of the solid component Z1 was added. The mixture was stirred at this temperature for 40 minutes and then heated to 115°C. During the heating process, 2.3 mmol of (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan and 8.9 mmol of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were added. The reaction mixture was maintained at 110°C for 1 hour. The liquid was filtered, the mixture was washed with titanium tetrachloride and then with hexane, and vacuum dried to obtain solid catalyst component Cat-1B. The molar ratio of furan compound to diether compound in the catalyst component is shown in Table 2. Testing showed that the content of magnesium in catalyst component Cat-1B was 5.06 parts by weight, and the content of electron donor was 5.87 parts by weight per part by weight of titanium.

[0163] (2) Propylene liquid phase bulk polymerization

[0164] Liquid-phase bulk polymerization of propylene was carried out in a 5-liter stainless steel autoclave. Under nitrogen, 5 mL of a hexane solution of triethylaluminum (0.5 mmol / mL), 1 mL of a hexane solution of cyclohexylmethyldimethoxysilane (CHMMS) (0.1 mmol / mL), and 7.5 mg of the solid catalyst Cat-1B were added to the autoclave in that order. The autoclave was closed, and hydrogen (the amount of hydrogen is shown in Table 2) and 2.3 L of liquid propylene were added. The temperature was raised to 70°C, and the reaction was continued for 1 hour. The temperature was then lowered, the pressure was released, and the product was discharged. The resulting propylene homopolymer was dried, weighed, and analyzed. The results are shown in Table 3.

[0165] Example 2B

[0166] A catalyst component was prepared and propylene liquid-phase bulk polymerization was carried out according to the method of Example 1B, except that the solid component Z2 was added. During the heating process, 3.2 mmol of (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan and 7.0 mmol of 9,9-bis(methoxymethyl)fluorene were added to obtain a solid catalyst component Cat-2B. Testing of the catalyst component Cat-2B revealed that, per part by weight of titanium, the magnesium content was 4.85 parts by weight, and the electron donor content was 5.53 parts by weight.

[0167] Example 3B

[0168] A catalyst component was prepared and propylene liquid-phase bulk polymerization was carried out according to the method of Example 1B, except that the solid component Z2 was added. During the heating process, 4.7 mmol of (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan and 6.5 mmol of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were added to obtain a solid catalyst component Cat-3B. Testing of the catalyst component Cat-3B revealed that, per part by weight of titanium, the magnesium content was 4.63 parts by weight, and the electron donor content was 4.45 parts by weight.

[0169] Example 4B

[0170] A catalyst component was prepared and liquid-phase bulk polymerization of propylene was carried out according to the method of Example 1B, except that 5.8 mmol of (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan and 6.3 mmol of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were added during the heating process to obtain catalyst component Cat-4B for olefin polymerization. Testing revealed that the magnesium content of catalyst component Cat-4B was 4.78 parts by weight, and the electron donor content was 4.64 parts by weight, per part by weight of titanium.

[0171] Example 5B

[0172] A catalyst component was prepared and liquid-phase bulk polymerization of propylene was carried out according to the method of Example 1B, except that 7.5 mmol of (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan and 4.2 mmol of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were added during the heating process to obtain a catalyst component Cat-5B for olefin polymerization. Testing of the catalyst component revealed that, per part by weight of titanium, the magnesium content was 4.64 parts by weight, and the electron donor content was 4.22 parts by weight.

[0173] Comparative Example 1B

[0174] A catalyst component was prepared and propylene liquid-phase bulk polymerization was carried out according to the method of Example 1B, except that, during the preparation of the catalyst component, 8 g of a magnesium halide support (prepared according to the method disclosed in Example 1 of CN1267508C) was added instead of the solid component Z1, and the (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan was replaced with an equal molar amount of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane to obtain a catalyst component DCat-1B for olefin polymerization.

[0175] Comparative Example 2B

[0176] A catalyst component was prepared and propylene liquid-phase bulk polymerization was carried out according to the method of Example 1B, except that, during the preparation of the catalyst component, 8 g of a magnesium halide support (prepared according to the method disclosed in Example 1 of CN1267508C) was added instead of the solid component Z1, and the 2-isopropyl-2-isopentyl-1,3-dimethoxypropane was replaced by an equal molar amount of (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan to obtain a catalyst component DCat-2B for olefin polymerization.

[0177] Table 2

[0178] Note: Span represents the width of particle size distribution, Span = (D90-D10) / D50; n 呋喃：二醚 It represents the molar ratio of furan compounds to diether compounds.

[0179] Table 3

[0180] As can be seen from the results of the examples and comparative examples in Tables 2-3, the particle size distribution of the catalyst component of the present invention is narrow, and when the catalyst component of the present invention is used, the catalyst has high hydrogen regulation sensitivity and stereospecificity as well as high polymerization activity, the content of the obtained polypropylene fine powder is low, and the molecular weight distribution of the prepared low melt index polymer is wider than the molecular weight distribution of the high melt index polymer, and the catalyst component of the present invention does not contain phthalate compounds (plasticizers).

[0181] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A catalyst component for olefin polymerization, It is characterized in that The catalyst components include magnesium, titanium, halogen and an electron donor; wherein the electron donor includes a furan compound and a diether compound; the furan compound is selected from at least one of the furan compounds shown in formula (I), In formula (I), R1 and R3 are each independently selected from hydrogen, C 1 -C 20 Straight chain alkyl, C 3 -C 20 Branched alkyl, C 3 -C 20 Cycloalkyl, C 6 -C 20 The aromatic group, C 7 -C 20 Arylalkyl or C 7 -C 20 R2 and R4 are each independently selected from C 1 -C 10 Straight chain alkyl, C 3 -C 10 Branched alkyl, C 3 -C 10 Cycloalkyl, C 6 -C 10 The aromatic group, C 7 -C 10 Arylalkyl or C 7 -C 10 Alkyl.

2. The catalyst component according to claim 1, in, The content of the furan compound is 0.01-2 moles, preferably 0.03-1.2 moles, per mole of the diether compound; And / or, R2 and R4 are each independently selected from C 1 -C 3 of a straight chain alkyl group.

3. The catalyst component according to claim 1 or 2, in, The furan compound is selected from at least one of the furan compounds represented by formula (I-1), Wherein, in formula (I-1), R1, R2, R3, and R4 are as described in claim 1 or 2; Preferably, the furan compound is selected from (3R, 3aR, 6S, 6aR)-3-methoxy-6-propoxyhexahydrofurano[3,2-b]furan, (3R, 3aR, 6S, 6aR)-3-methoxy-6-ethoxyhexahydrofurano[3,2-b]furan, At least one of (3R,3aR,6S,6aR)-3,6-dimethoxyhexahydrofuro[3,2-b]furan, (3R,3aR,6S,6aR)-3,6-diethoxyhexahydrofuro[3,2-b]furan, and (3R,3aR,6S,6aR)-3,6-dipropoxyhexahydrofuro[3,2-b]furan.

4. The catalyst component according to any one of claims 1 to 3, in, The diether compound is selected from at least one of the diether compounds represented by formula (II), In formula (II), R Ⅰ , R Ⅱ , R Ⅲ , R Ⅳ , R Ⅴ and R Ⅵ are the same or different, each independently selected from hydrogen, halogen atoms, C 1 -C 20 Straight chain alkyl, C 3 -C 20 Branched alkyl, C 3 -C 20 Cycloalkyl, C 6 -C 20 The aromatic group, C 7 -C 20 Arylalkyl or C 7 -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 C 1 -C 20 Straight chain alkyl, C 3 -C 20 Branched alkyl, C 3 -C 20 Cycloalkyl, C 6 -C 20 The aromatic group, C 7 -C 20 Alkyl or C 7 -C 20 of aralkyl.

5. The catalyst component according to claim 4, in, R Ⅰ , R Ⅱ , R Ⅲ , R Ⅳ , R Ⅴ and R Ⅵ are each independently selected from hydrogen, C 1 -C 20 Straight chain alkyl, C 3 -C 20 Branched alkyl; and / or, R Ⅲ , R Ⅳ Bonding to form a fluorene ring; and / or, R Ⅶ and R Ⅷ Each independently selected from C 1 -C 5 Straight chain alkyl, C 3 -C 5 of branched chain alkyl.

6. The catalyst component according to any one of claims 1 to 5, in, 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-(diphenylethyl)-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, 2,2-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-iso Propyl-1,3-dimethoxypropane, 2-isopropyl-2-isopentyl-1,3-dimethoxypropane, 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- At least one of 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-bis(methoxymethyl)fluorene.

7. The catalyst component according to any one of claims 1 to 6, in, Based on each weight part of titanium element, the content of magnesium element is 2-18 weight parts, preferably 3-16 weight parts; the content of electron donor is 2-17 weight parts, preferably 3-15 weight parts; And / or, the source of the magnesium element is at least one selected from magnesium halide, magnesium alcoholate, magnesium halogenated alcoholate, magnesium halide alcohol adduct, magnesium halide adduct and magnesium-containing solid component.

8. The catalyst component according to any one of claims 1 to 7, in, The source of the titanium element is selected from the general formula Ti(OR′) 3-a Z a and / or Ti(OR′) 4-b Z b A titanium compound wherein R′ is C 1 -C 20 alkyl, Z is F, Cl, Br or I, a is an integer of 1-3, and b is an integer of 1-4; Preferably, the source of the titanium element is selected from 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.

9. A method for preparing a catalyst component for olefin polymerization, It is characterized in that The method comprises: mixing a magnesium source, a titanium source and an electron donor, wherein the electron donor comprises a furan compound and a diether compound; the furan compound is selected from at least one of the furan compounds shown in formula (I), In formula (I), R1 and R3 are each independently selected from hydrogen, C 1 -C 20 Straight chain alkyl, C 3 -C 20 Branched alkyl, C 3 -C 20 Cycloalkyl, C 6 -C 20 The aromatic group, C 7 -C 20 Arylalkyl or C 7 -C 20 R2 and R4 are each independently selected from C 1 -C 10 Straight chain alkyl, C 3 -C 10 Branched alkyl, C 3 -C 10 Cycloalkyl, C 6 -C 10 The aromatic group, C 7 -C 10 Arylalkyl or C 7 -C 10 Alkyl.

10. The method according to claim 9, in, The amount of the furan compound used is 0.1-3 moles per mole of the diether compound; more preferably 0.1-2 moles, and further preferably 0.15-1.8 moles.

11. A catalyst system for olefin polymerization, It is characterized in that The catalyst system comprises: (1) The catalyst component according to any one of claims 1 to 8 and / or the catalyst component prepared by the method according to claim 9 or 10; (2) at least one aluminum alkyl; and (3) Optional other electron donors.

12. The catalyst system according to claim 11, in, The molar ratio of the alkyl aluminum calculated as aluminum element to the catalyst component calculated as titanium element is 1-2000:1, preferably 20-500:1, more preferably 30-300:1; And / or, the molar ratio of the other electron donor to the alkyl aluminum compound calculated as aluminum element is 1:1-300, preferably 1:2-100.

13. The catalyst system according to claim 11 or 12, in, The general formula of the alkylaluminum is AlR″ n1 X 1 3-n1 , where R″ is an alkyl group of C 1 -C 8 , the hydrogen on the alkyl group is optionally substituted by a halogen atom, and X 1 is a halogen, and n1 is an integer where 0 < n1 ≤ 3; Preferably, the alkylaluminum is 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.

14. The catalyst system according to any one of claims 11 to 13, in, The other 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 other 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.

15. Use of the catalyst component according to any one of claims 1 to 8 and / or the catalyst component prepared by the method according to claim 9 or 10 and / or the catalyst system according to any one of claims 11 to 14 in olefin polymerization.

16. A method for the polymerization of olefins, It is characterized in that The olefin polymerization method comprises: carrying out an olefin polymerization reaction in the presence of the catalyst component described in any one of claims 1 to 8 and / or the catalyst component prepared by the method described in claim 9 or 10 and / or the catalyst system described in any one of claims 11 to 14; Preferably, the olefin is selected from the formula CH 2 =CHR"', wherein R"' is hydrogen, C 1 -C 6 Alkyl, C 6 -C 12 The aromatic group; Preferably, the polymerization reaction conditions include: temperature of 0-150° C., preferably 60-90° C.; pressure of 0.01-10 MPa, preferably 0.01-5 MPa.

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