Catalyst component for olefin polymerization, catalyst and application thereof

Abstract

The invention provides a catalyst component for olefin polymerization, a catalyst and application thereof. The catalyst component is prepared from the following components: Mg, Ti, halogen and a 2, 6-diformate 4-pyrone internal electron donor, wherein the 2, 6-dicarboxylate-4-pyrone internal electron donor has a structure shown as a formula I: # imgabs0, the catalytic activity of the catalyst component and the catalyst is high and is generally higher than that of common phthalate and diether internal electron donor catalysts in the industry, and a polymer obtained by catalytic polymerization is regular in particle size, high in bulk density and high in isotacticity, and has a good application prospect. The molecular weight distribution is moderate.

Description

Technical Field

[0001] The invention relates to a solid catalyst component for olefin polymerization, belonging to the field of polyolefin catalysts. Background Art

[0002] At present, Ziegler-Natta catalysts (ZN catalysts) still occupy a dominant position in polyolefin production. The development focus of most ZN catalysts is on the development of highly active and highly stereospecific catalysts and improving the copolymerization ability of catalysts. In addition, due to the high catalytic efficiency of traditional ZN catalysts (transition metal compounds such as titanium chemically bonded to a magnesium-containing carrier), the polymer produced has good comprehensive performance and low cost. At present, most catalysts for producing polypropylene in the world are still based on ZN catalytic systems, which are characterized by high activity, high stereoregularity, long life and customized product structure. From the development process of ZN catalysts, it can be seen that as early as the emergence of the first generation of catalysts, it was found that adding a third component (mostly electron donors, also known as Lewis bases, among which those added during the catalyst preparation process are called internal electron donors, and those added during the polymerization process are called external electron donors) will have a great influence on the polymerization behavior of olefins and the properties of polymers; changing the internal electron donor in the catalyst can change the properties of the catalyst active center to the greatest extent possible, thereby changing the performance of the catalyst to the greatest extent. Therefore, the development of new electron donors has always been a hot spot in the research and development of ZN polypropylene catalysts.

[0003] The relatively distinctive high-performance internal electron donor compounds in the prior art mainly include: (1) fatty acid esters and aromatic acid ester compounds, mainly represented by phthalate compounds; (2) diether compounds (for example, compounds disclosed in EP0361493 and EP0728724); (3) succinate compounds (for example, compounds disclosed in WO9856834, WO0063261, and WO03022894); (4) glycol ester compounds (for example, compounds disclosed in WO9856834, WO0063261, and WO03022894); (5) compounds with other functional groups (compounds disclosed in CN1105671, CN1242780, and US20060128558), etc. However, in practical applications, the above compounds have certain problems as internal electron donors for olefin polymerization catalysts. Although the catalysts using 1,3-diether compounds as internal electron donors have higher activity and good hydrogen tuning sensitivity, the relative molecular mass distribution of the produced PP is narrow, which is not conducive to the development of different grades of PP; the advantage of using succinate compounds as internal electron donors is that the relative molecular mass distribution of the synthesized PP is relatively wide, but the disadvantage is that the stereoregularity of PP and the hydrogen tuning sensitivity of the catalyst need to be improved; and the overall activity of the diol ester catalytic system is not as ideal as the diether system.

[0004] At present, the most widely used polyolefin internal electron donor in industry is phthalate compounds, which have medium catalyst activity, good stereoselectivity and low price. However, phthalate compounds, as commonly used plasticizers, have great harm to human reproductive health and the environment, and there is a great demand for replacement. At present, the use of most phthalate substances has been restricted. Therefore, it is one of the common research and development goals in the field of polyolefin catalysts in recent years to develop a new electron donor with excellent activity, good stereospecificity, good comprehensive performance and low cost to replace the phthalate electron donor compounds widely used in the prior art and apply them to the preparation of efficient Ziegler-Natta catalysts. Summary of the invention

[0005] In order to solve the above problems, the purpose of the present invention is to provide a catalyst component, a catalyst and its application for olefin polymerization, the catalyst component and the catalyst have high catalytic activity, which is generally higher than the phthalate ester and diether internal electron donor catalysts commonly used in industry, and the polymer obtained by catalytic polymerization has regular particle size, high bulk density, high isotacticity and moderate molecular weight distribution.

[0006] In order to achieve the above object, the present invention provides a catalyst component for olefin polymerization, which comprises: Mg, Ti, halogen, and 2,6-dicarboxylic acid ester-4-pyrone internal electron donor; wherein the 2,6-dicarboxylic acid ester-4-pyrone internal electron donor has a structure shown in Formula I:

[0007]

[0008] In Formula I, R 1 , R 2 , R 3 and R 4 are the same or different, each independently selected from H, halogen, C1-C 20 More preferably, R 1 , R 2 , R 3 and R 4 Each of the above mentioned heteroatoms contains one or more heteroatoms selected from N, O, S, P, Si and halogen; more preferably, R 1 , R 2 , R 3 and R 4 Two or more of them are bonded to each other to form a ring.

[0009] According to a specific embodiment of the present invention, preferably, in Formula I, R 1 , R 2 , R 3 and R 4the same or different, each independently selected from H, halogen, the following substituents with less than 20 carbon atoms: straight-chain or branched alkyl, cycloalkyl, alkenyl, ester, phenyl, alkylphenyl, phenylalkyl, indenyl, benzyl, halogenated alkyl, alkyl containing heteroatoms, halogenated cycloalkyl, cycloalkyl containing heteroatoms, halogenated phenyl, phenyl containing heteroatoms, halogenated alkylphenyl, alkylphenyl containing heteroatoms, halogenated phenylalkyl, phenylalkyl containing heteroatoms, halogenated indenyl, indenyl containing heteroatoms, halogenated benzyl, benzyl containing heteroatoms, heterocyclic aromatic substituents; the heteroatoms include one or a combination of two or more of N, O, S, P, and Si.

[0010] According to a specific embodiment of the present invention, preferably, in Formula I, R 1 , R 2 , R 3 and R 4 are each independently selected from H, halogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, cyclopentyl, n-hexyl, cyclohexyl, heptyl, octyl, nonyl, decyl, C 11 -C 20 The straight chain or branched alkyl group of 20 carbon atoms or the following substituents within 20 carbon atoms: alkenyl, phenyl, m-chlorophenyl, p-chlorophenyl, o-chlorophenyl, m-methoxyphenyl, p-methoxyphenyl, o-methoxyphenyl, p-methylphenyl, p-nitrophenyl, m-nitrophenyl, benzyl and its derivatives, phenethyl and its derivatives, furyl, pyrrolyl, thienyl and indenyl; more preferably, the alkenyl group includes propenyl, butenyl, pentenyl and hexenyl.

[0011] According to a specific embodiment of the present invention, preferably, R 1 , R 2 Each is independently selected from phenyl and its derivatives, and is further preferably selected from halogenated phenyl.

[0012] According to a specific embodiment of the present invention, preferably, the 2,6-dicarboxylic acid ester-4-pyrone internal electron donor includes 2,6-dicarboxylic acid di-n-butyl ester-4-pyrone, 2,6-dicarboxylic acid diethyl ester-4-pyrone, 2,6-dicarboxylic acid diisobutyl ester-4-pyrone, 2,6-dicarboxylic acid dicyclohexyl ester-4-pyrone, 2,6-dicarboxylic acid di (tetradecyl) ester-4-pyrone, 2,6-dicarboxylic acid diphenyl ester-4-pyrone, 2,6- 2,6-dicarboxylic acid diphenyl ethyl ester-4-pyrone, 2,6-dicarboxylic acid di-m-chlorophenyl ester-4-pyrone, 2,6-dicarboxylic acid di-p-chlorophenyl ester-4-pyrone, 2,6-dicarboxylic acid di-o-chlorophenyl ester-4-pyrone, 2,6-dicarboxylic acid di-p-methylphenyl ester-4-pyrone, 2,6-dicarboxylic acid di-m-methoxyphenyl ester-4-pyrone, 2,6-dicarboxylic acid di-p-methoxyphenyl ester-4-pyrone, 2,6-dicarboxylic acid di-o-methoxyphenyl ester-4-pyrone, 2, 2,6-dicarboxylic acid di(α-furanylmethyl)-4-pyrone, 2,6-dicarboxylic acid di(5-pentenyl)-4-pyrone, 2,6-dicarboxylic acid di-p-nitrophenyl-4-pyrone, 2,6-dicarboxylic acid di-n-butyl-4-pyrone, 2,6-dicarboxylic acid di-n-butyl-3,5-dimethyl-4-pyrone, 2,6-dicarboxylic acid diethyl-3-phenyl-4-pyrone, 2,6-dicarboxylic acid diethyl-3-chloro ... One or a combination of two or more of diethyl 2,6-dicarboxylate-3-bromo-4-pyrone, diisopropyl 2,6-dicarboxylate-4-pyrone, dibenzyl 2,6-dicarboxylate-4-pyrone, ethyl 2-carboxylate-6-n-butyl carboxylate-4-pyrone, ethyl 2-carboxylate-6-phenyl carboxylate-4-pyrone, di-n-butyl 2,6-dicarboxylate-3-methyl-4-pyrone, and di-n-butyl 2,6-dicarboxylate-3-methyl-5-ethyl-4-pyrone.

[0013] The 2,6-dicarboxylate-4-pyrone compound shown in Formula I can be synthesized by the following preparation methods including but not limited to:

[0014] The synthetic route is shown in Reaction Formula I. Esterification of oxalic acid is performed to obtain the corresponding oxalic acid diester (part of the oxalic acid diester can be purchased directly), and then the corresponding product can be obtained by reacting with acetone or other substituted ketones.

[0015] Reaction formula Ⅰ:

[0016]

[0017] It can also be prepared by a synthetic route as shown in reaction formula II. The raw materials used in this route are cheap diethyl oxalate and acetone or other substituted ketones, which are then reacted with an alcohol to obtain a substituted 2,6-dicarboxylate-4-pyrone compound. Only two steps are required to obtain the target product, and a variety of alcohols R can be selected. 1OH to enrich the product structure; or react with a mixture of two alcohols (the synthesis route is shown in Reaction Formula III) to obtain a mixture of three substituted 2,6-dicarboxylic acid ester-4-pyrone, which can be directly used as an internal electron donor without separation. The ratio of each component in the mixture can be adjusted by the addition ratio of the two alcohols in the reactants, and the ratio of each component can be characterized and determined by analytical methods such as chromatography-mass spectrometry technology and nuclear magnetic resonance. In addition, the product of the first step, 2,6-dicarboxylic acid-4-pyrone (CAS No.: 99-32-1), can also be directly purchased, and 2,6-dicarboxylic acid ester-4-pyrone can be obtained through a one-step esterification reaction;

[0018] Reaction formula II:

[0019]

[0020] Reaction formula III:

[0021]

[0022] According to a specific embodiment of the present invention, preferably, the catalyst component comprises a titanium compound, a magnesium compound, and the 2,6-dicarboxylate-4-pyrone internal electron donor; the precursor of the magnesium compound is selected from X n Mg(OR a ) 2-n 、MgCl2·mR a OH, R a 2-n MgX n , MgCl2 / SiO2, MgCl2 / Al2O3, a mixture of magnesium halide and titanium alkoxide, or a combination of two or more thereof, wherein m is 0.1-6, 0≤n≤2, X is a halogen, R a C1-C 20 The general formula of the titanium compound is TiX N (OR b ) 4-N , where R b C1-C 20 The hydrocarbon group is: X is halogen, and N is 1-4.

[0023] According to a specific embodiment of the present invention, preferably, the magnesium compound is an alcoholate of magnesium dihalide; or, the magnesium compound is a liquid magnesium compound (a magnesium compound dissolved in a liquid); or, the magnesium compound is a derivative of a magnesium dihalide molecule in which at least one halogen atom is replaced by a hydrocarbonoxy group or a halogenated hydrocarbonoxy group; more preferably, it is a hydrocarbonoxy magnesium compound; further preferably, it is an alkoxy magnesium and / or an aryloxy magnesium.

[0024] According to a specific embodiment of the present invention, preferably, the titanium compound includes one or a combination of two or more of titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, and alkoxy titanium halide.

[0025] According to a specific embodiment of the present invention, preferably, the alkyl titanium halide includes one or a combination of two or more of methoxytitanium trichloride, ethoxytitanium trichloride, propoxytitanium trichloride, n-butoxytitanium trichloride, dimethoxytitanium dichloride, diethoxytitanium dichloride, dipropoxytitanium dichloride, di-n-butoxytitanium dichloride, trimethoxytitanium chloride, triethoxytitanium chloride, tripropoxytitanium chloride, and tri-n-butoxytitanium chloride.

[0026] According to a specific embodiment of the present invention, preferably, the titanium compound is titanium tetrachloride.

[0027] According to a specific embodiment of the present invention, preferably, the molar ratio of the 2,6-dicarboxylate-4-pyrone internal electron donor to the magnesium compound calculated as magnesium element is 0.01-5.0:1, preferably 0.05-3.0:1.

[0028] The present invention does not particularly limit the preparation method of the above-mentioned solid catalyst component, which can be carried out according to the following methods:

[0029] Method 1: A magnesium alcoholate or a magnesium chloroalcoholate is reacted with an excess of TiCl4 and an internal electron donor compound at a temperature of 80°C to 135°C; preferably, a compound of the general formula TiX N (OR b ) 4-N Titanium compounds (where R b C1-C 20 A hydrocarbon group, X is a halogen, N = 1-4; preferably TiCl4) and a general formula of MgCl2·mR a OH adduct (wherein m is a number of 0.1-6, preferably 2-4, and R a C1-C 20 The solid catalyst component is prepared by reacting an internal electron donor with a hydrocarbon group; wherein the general formula is MgCl2·mR a The adduct of OH can be suitably made into spherical shape by the following method: in the presence of an inert hydrocarbon immiscible with the adduct, alcohol and magnesium chloride are mixed, and the emulsion is rapidly quenched, thereby solidifying the adduct in the form of spherical particles (refer to the disclosures of US4399054 and US4469648). The spherical adduct obtained in this way can be directly reacted with the titanium compound, or it can be previously subjected to heat-controlled dealcoholation (80°C-130°C) to obtain a dealcoholated adduct (wherein the molar number of alcohol is generally less than 3, preferably between 0.1-2.5), and then subjected to the subsequent reaction;

[0030] For example, the adduct or dealcohol adduct is suspended in cold TiCl4 (generally -25°C-0°C) to react with the titanium compound, and the mixture of the two is heated to 80°C-130°C and maintained at this temperature for 0.5-2 hours, wherein the treatment with TiCl4 can be carried out once or more, and an internal electron donor compound can be added during the treatment with TiCl4, and this treatment can be repeated once or more;

[0031] Method 2: Dissolve the magnesium compound in a solvent system consisting of an organic epoxy compound, an organic phosphine compound and an inert diluent to form a uniform solution, and then mix it with a titanium compound, and precipitate a solid in the presence of a precipitation aid; the solid is treated with an internal electron donor compound to load the internal electron donor compound on the solid, and if necessary, further treated with titanium tetrahalide and an inert diluent; the precipitation aid is one of an organic anhydride, an organic acid, an ether, and a ketone. The components are calculated per mole of magnesium halide, and the organic epoxy compound is 0.2-10 mol, the organic phosphine compound is 0.1-3 mol, the precipitation aid is 0-1.0 mol, and the Ti compound is 0.5-150 mol (calculated as mole of titanium element);

[0032] Method 3: Use TiCl4 or an aromatic hydrocarbon solution of alkoxy titanium (e.g., toluene, xylene, etc.) to react with a dialkoxy magnesium compound such as dialkoxy magnesium (preferably diethoxy magnesium) or diaryloxy magnesium at -25-0°C, and halogenate at 80°C-130°C. The treatment with the aromatic hydrocarbon solution of TiCl4 can be repeated once or multiple times, and the internal electron donor compound is added once or in batches during multiple such treatments. For example, the preparation method of the titanium-containing solid catalyst component disclosed in US5077357 can be used for preparation: add ethoxy magnesium, tetraethoxy titanium, o-cresol, ethanol and chlorobenzene in sequence, and stir; quickly add the TiCl4 / chlorobenzene solution to the above liquid, heat it until it is completely dissolved, and then continue to heat it to a specific temperature; use N2 bubbling to take away the ethanol reactant and continue stirring for a certain time, then use hot chlorobenzene to wash once, isooctane to wash twice, and then N2 to dry to obtain the carrier. Or according to another example: TiCl4, tetraethoxytitanium, ethoxymagnesium and o-cresol are added to chlorobenzene in sequence and stirred; ethanol is added and stirred for 3 hours at high temperature after the ethoxymagnesium is dissolved; hot filtering is performed and then washed once with warm chlorobenzene and once with isooctane, and finally dried with N2;

[0033] Method 4: Magnesium dichloride is preactivated according to existing methods and then treated with excess TiCl4 at a temperature of about 80°C to 135°C, wherein an internal electron donor compound is contained in the solution. The TiCl4 is treated multiple times and the solid is washed with hexane to remove any unreacted TiCl4;

[0034] Method 5: Prepare with reference to the preparation method of titanium-containing solid catalyst component disclosed in CN1208045: first, a liquid magnesium compound and a liquid titanium compound are contacted at low temperature in the presence of a compound selected from alcohols, phenols, ketones, aldehydes, ethers, amines, pyridines and esters to precipitate a solid, the contact temperature is generally -70°C to 200°C, preferably -30°C to 130°C, and an internal electron donor compound is used during the contact process;

[0035] Method 6: Grind anhydrous magnesium chloride and an internal electron donor compound together under conditions where magnesium dichloride is activated, and the product obtained in this way can be treated once or multiple times with excess TiCl4 at a temperature of 80°C-130°C, and then washed with a hydrocarbon solvent until it is free of chloride ions. A further detailed method is: the product obtained by co-grinding anhydrous magnesium dichloride, a titanium compound and an internal electron donor compound is treated with a halogenated hydrocarbon such as 1,2-dichloroethane, chlorobenzene, dichloromethane, etc., the treatment being carried out at a temperature between 40°C and the boiling point of the halogenated hydrocarbon for 1-4 hours, and then the product is usually washed with an inert hydrocarbon solvent such as hexane;

[0036] Method 7: A magnesium compound supported on an inorganic oxide such as SiO2, alumina or porous silica gel is used as a carrier for preparation, and then activated by a well-known method, and then treated with an excess of TiCl4 at a temperature of about 80°C-135°C, and an internal electron donor compound is added during the treatment process.

[0037] The reaction of the above catalyst components leads to the formation of magnesium halide in an active form; general crystalline magnesium halide has a regular structure and can carry very little Ti, so the catalytic activity is low. To prepare a highly active supported catalyst, the magnesium halide must be activated; the activation treatment method includes using physical and / or chemical methods to make it into microcrystals so that the active center is loaded on the surface, edge and defect of the magnesium halide. The treated magnesium halide microcrystal suitable for loading Ti is "active magnesium halide". In addition to these reactions, other methods are also known in the literature to make compound starting materials other than magnesium halide form magnesium halide in an active form.

[0038] In any of the methods for preparing the catalyst components, the internal electron donor compound can be added directly as such or in an alternative manner, such as by preparing it in situ using a suitable precursor that can be converted in the desired internal electron donor compound, such as by known chemical reactions such as esterification, transesterification, etc. Typically, the internal electron donor compound is used in a molar ratio of 0.01-5:1, preferably 0.05-3.0:1, relative to the molar number of MgCl2; in addition, the internal electron donor compound can be added simultaneously or separately during the preparation process in batches or in parts, in any order and in any combination.

[0039] The present invention also provides a catalyst for olefin polymerization, which comprises the above catalyst component and an organic aluminum compound.

[0040] According to a specific embodiment of the present invention, preferably, the general formula of the organoaluminum compound is AlR c p X (3-p) , where R c is hydrogen or C1-C 20 wherein X is a halogen and p is an integer of 0≤p≤3.

[0041] According to a specific embodiment of the present invention, preferably, the organoaluminum compound includes one or a combination of two or more of trialkylaluminum compounds, alkylaluminum halides, alkylaluminum hydrides, alkylaluminum sesquichlorides, and alkylaluminoxanes.

[0042] According to a specific embodiment of the present invention, preferably, the trialkylaluminum compound includes one or a combination of two or more of trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri-n-hexylaluminum, and trioctylaluminum; the alkylaluminum halide includes AlEt2Cl; and the alkylaluminum sesquichloride includes Al2Et3Cl3.

[0043] According to a specific embodiment of the present invention, preferably, the molar ratio of the organic aluminum compound to the titanium atom in the catalyst component is 1-1000:1, more preferably 50-800:1.

[0044] According to a specific embodiment of the present invention, preferably, the raw material composition of the catalyst also includes an external electron donor.

[0045] According to a specific embodiment of the present invention, preferably, the external electron donor is a siloxane compound.

[0046] According to a specific embodiment of the present invention, preferably, the general formula of the siloxane compound is R' t Si(OR”) 4-t , wherein R' and R" are each independently selected from C1-C18 A hydrocarbon group, t is an integer of 0≤t≤3; more preferably, R' and R" each contain a heteroatom; more preferably, the heteroatom includes one or a combination of two or more of N, O, S, P, and Si.

[0047] According to a specific embodiment of the present invention, preferably, the siloxane compound includes trimethylmethoxysilane, trimethylethoxysilane, tri-n-propylmethoxysilane, tri-n-propylethoxysilane, tri-n-butylmethoxysilane, triisobutylethoxysilane, tricyclohexylmethoxysilane, tricyclohexylethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, di-n-propyldimethoxysilane, diisopropyldimethoxysilane, di-n-propyldiethoxysilane, diisopropyldiethoxysilane, di-n-butyldiethoxysilane, diisobutyldiethoxysilane, di-tert-butyldimethoxysilane, di-tert-butyldimethoxysilane, di-n-butyldimethoxysilane, diisobutyldimethoxysilane silane, di-tert-butyldiethoxysilane, di-n-butyldiethoxysilane, n-butylmethyldimethoxysilane, di(2-ethylhexyl)dimethoxysilane, di(2-ethylhexyl)diethoxysilane, dicyclohexyldimethoxysilane, dicyclohexyldiethoxysilane, dicyclopentyldimethoxysilane, dicyclopentyldiethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, cyclohexylethyldimethoxysilane, cyclohexylisopropyldimethoxysilane, cyclohexylethyldiethoxysilane, cyclopentylmethyldimethoxysilane, cyclopentylethyldiethoxysilane, cyclopentylisopropyldiethoxysilane, cyclopentylisobutyldimethoxysilane, cyclohexyl-n-propyl Dimethoxysilane, cyclohexyl-n-propyldiethoxysilane, cyclohexyl-n-butyldiethoxysilane, amylmethyldimethoxysilane, amylmethyldiethoxysilane, amylethyldimethoxysilane, amylethyldiethoxysilane, cyclohexyldimethylmethoxysilane, cyclohexyldiethylmethoxysilane, cyclohexyldiethylmethoxysilane, cyclohexyldiethylethoxysilane, 2-ethylhexyltrimethoxysilane, cyclohexyldimethoxysilane, cyclohexyldiethoxysilane, 2-ethylhexyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane, n-butyl trimethoxysilane, isobutyltrimethoxysilane, tert-butyltrimethoxysilane, n-butyltriethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, cyclopentyltrimethoxysilane, cyclopentyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-ethylhexyltrimethoxysilane, 2-ethylhexyltriethoxysilane, pentyltrimethoxysilane, pentyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, cyclohexylcyclopentyldimethoxysilane, cyclohexylcyclopentyldiethoxysilane, cyclohexylcyclopentyldipropoxysilane, 3-methylcyclohexylcyclopentyldimethoxysilane, 4-methylcyclohexylcyclopentyldimethoxysilane, 3,5-dimethylcyclohexylcyclopentyldimethoxysilane, 3-methylcyclohexylcyclohexyldimethoxysilane, bis(3-methylcyclohexyl)dimethoxysilane, 4-methylcyclohexylcyclohexyldimethoxysilane, bis(4-methylcyclohexyl)dimethoxysilane, 3,5-dimethylcyclohexylcyclohexyldimethoxysilane, bis(3,5-dimethylcyclohexyl)dimethoxysilane, tetrapropoxysilane, tetrabutoxysilane, or a combination of two or more thereof.

[0048] According to a specific embodiment of the present invention, preferably, the siloxane compound includes di-n-propyl dimethoxysilane, diisopropyl dimethoxysilane, di-n-butyl dimethoxysilane, diisobutyl dimethoxysilane, di-tert-butyl dimethoxysilane, di-n-butyl diethoxysilane, tert-butyl trimethoxysilane, dicyclohexyl dimethoxysilane, dicyclohexyl diethoxysilane, cyclohexyl methyl dimethoxysilane, cyclohexyl ethyl diethoxysilane, One or a combination of two or more of cyclohexylethyldimethoxysilane, cyclohexylethyldiethoxysilane, cyclopentylmethyldimethoxysilane, cyclopentylmethyldiethoxysilane, cyclopentylethyldimethoxysilane, cyclohexylcyclopentyldimethoxysilane, cyclohexylcyclopentyldiethoxysilane, 3-methylcyclohexylcyclopentyldimethoxysilane, 4-methylcyclohexylcyclopentyldimethoxysilane and 3,5-dimethylcyclopentyldimethoxysilane.

[0049] According to a specific embodiment of the present invention, preferably, the siloxane compound includes cyclohexylmethyldimethoxysilane, diisopropyldimethoxysilane, di-n-butyldimethoxysilane, diisobutyldimethoxysilane, diphenyldimethoxysilane, phenyltriethoxysilane, methyl-tert-butyldimethoxysilane, dicyclopentyldimethoxysilane, 2-ethylpiperidinyl-2-tert-butyldimethoxysilane, (1,1,1-trifluoro-2-propyl)-2-ethylpiperidinyldimethoxysilane, (1,1,1-trifluoro-2-propyl)-methyl-methoxysilane, cyclohexyltrimethoxysilane, tert-butyltrimethoxysilane, tert-hexyltrimethoxysilane, or a combination of two or more thereof.

[0050] According to a specific embodiment of the present invention, preferably, the molar ratio of silicon in the external electron donor to titanium in the catalyst component is 0.002-100:1, more preferably 0.01-20:1, and further preferably 0.01-5:1.

[0051] The invention also provides application of the catalyst in olefin polymerization.

[0052] According to a specific embodiment of the present invention, preferably, the olefin includes a linear or branched olefin, such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 3-methyl-1-butene, 4-methyl-1-pentene, butadiene, vinylcyclopentene, vinylcyclohexene, one or a combination of two or more thereof.

[0053] According to a specific embodiment of the present invention, preferably, the polymerization comprises ethylene and / or propylene polymerization.

[0054] According to a specific embodiment of the present invention, preferably, the polymerization includes homopolymerization or copolymerization.

[0055] According to a specific embodiment of the present invention, preferably, during the catalytic process, the order of adding the components in the catalyst is arbitrary, preferably the organoaluminum compound is first added to the polymerization system, then the external electron donor is added, and finally the catalyst component is added.

[0056] According to a specific embodiment of the present invention, preferably, in the above application, the polymerization process can be carried out with or without a solvent; the olefin monomer can be in gas phase or liquid phase; more preferably, hydrogen can be further added as a molecular weight regulator (polymerization can also be carried out without a molecular weight regulator); continuous polymerization or batch polymerization process can be applied, and the polymerization reaction can be carried out in one step, two steps or multiple steps.

[0057] According to a specific embodiment of the present invention, preferably, the polymerization temperature is ≤200°C, more preferably 20-100°C, and further preferably 40-80°C; the polymerization pressure is ≤10MPa, more preferably 0.3-5MPa.

[0058] The present invention has the following beneficial effects:

[0059] The present invention provides a catalyst component with 2,6-dicarboxylic acid ester-4-pyrone as an internal electron donor. The internal electron donor compound contained in the catalyst component contains multiple oxygen-containing functional groups such as ketone, ether, ester, etc. on the six-membered ring structure, which is easier to coordinate with the catalyst active center than the internal electron donor with single oxygen or double oxygen functional groups. In addition, the skeleton stereo configuration of the structure and the steric hindrance of different substituents are conducive to the functional groups participating in the formation of the active center; the catalyst prepared by the internal electron donor compounds with multiple different substituents in the same series generally has higher activity than the catalyst of phthalate internal electron donors, and higher than diether catalysts, and has good stereoselectivity, high isotacticity of the obtained polymer, and moderate molecular weight distribution. The polyolefin catalyst prepared by using this type of internal electron donor can avoid the use of phthalate internal electron donors with reproductive and environmental toxicity, and has broader industrial application prospects in countries and regions that restrict the use of phthalate plasticizers. DETAILED DESCRIPTION

[0060] In order to have a clearer understanding of the technical features, purposes and beneficial effects of the present invention, the technical solution of the present invention is now described in detail below, but it should not be construed as limiting the applicable scope of the present invention.

[0061] The operations for preparing the catalysts in the following examples were all carried out under the protection of high-purity nitrogen.

[0062] The isotacticity of a polymer is determined by the heptane extraction method (extraction with boiling heptane for 6 hours): two grams of a dry polymer sample is placed in an extractor and extracted with boiling heptane for 6 hours. The residue is then dried to a constant weight, and the ratio of the obtained polymer weight (g) to 2 is the isotacticity.

[0063] The bulk density of the polymer was determined using the JB / T 2412-2008 method.

[0064] The molecular weight distribution of the polymer was determined by a PL-220 gel permeation chromatograph using trichlorobenzene as solvent at 150°C (standard sample: polystyrene, flow rate 1.0 mL / min, column: 3xPlgel 10um M1Xed-B 300x7.5nm).

[0065] Preparation Example: Synthesis of 2,6-dicarboxylate-4-pyrone compounds shown in Formula I

[0066] 1. The synthesis of 2,6-di-n-butyl dicarboxylate-4-pyrone is as follows:

[0067] (1) Sodium (11.8 g, 0.5 mol, 2.04 eq.) was dissolved in anhydrous ethanol (180 mL) to obtain a solution for use; anhydrous acetone (14.5 g, 19 mL, 0.25 mol, 1 eq.) and diethyl oxalate (77.5 g, 72 mL, 0.53 mol, 2.12 eq.) were added to the solution obtained above within 15 minutes to form a yellow precipitate; the reaction mixture was maintained at 60° C. for one hour, and HCl (aq. 37%, 100 mL) and water (50 mL) were added. The solution was stirred at 50°C for 20 hours, after which water and ethanol (about 230 mL) were removed under reduced pressure, and then water (150 mL) and HCl (aq. 37%, 25 mL) were added to the mixture and stirred until silica gel TLC (eluent: 3 / 7 (v / v), 10% NaCl aqueous solution / ethanol) showed only one point. After cooling to room temperature, the crystals were filtered out, washed with water, and then washed with cold acetone, and the crude product was recrystallized to obtain white powder 4-pyrone-2,6-dicarboxylic acid (35.0 g, yield: 76%);

[0068] (2) In a 1 L three-necked flask, 4-pyrone-2,6-dicarboxylic acid (5.5 g), n-butanol (100 mL), and concentrated sulfuric acid (0.6 mL) were added, heated to reflux for 2 hours, and cooled to room temperature; the reaction solution was poured into a saturated sodium bicarbonate solution, extracted twice with ethyl acetate (100 mL×2), the organic phases were combined, washed with saturated brine (100 mL×2), concentrated and recrystallized to obtain the product 2,6-di-n-butyl dicarboxylate-4-pyrone (a1, 7.1 g, yield 79%). 1 H NMR (500 MHz, Chloroform-d) δ / ppm: 6.81 (s, 2H), 4.14 (t, J = 8.7 Hz, 4H), 1.77 (p, J = 8.9 Hz, 4H), 1.52–1.41 (m, 4H), 0.97 (t, J = 5.6 Hz, 6H). The specific structural information is shown in Table 1.

[0069] 2. Other 2,6-dicarboxylic acid ester-4-pyrone compounds (a2-a25) are synthesized by the above-mentioned route (other existing synthetic routes may also be used), the starting material is selected from oxalic acid or diethyl oxalate, and is subjected to addition reaction with acetone or other ketones, and then esterified with one or two alcohols to obtain the corresponding 2,6-dicarboxylic acid ester-4-pyrone products. When reacting with two alcohols, a mixture of three products is obtained, which can be directly used as an internal electron donor composition without separation. The structures and NMR results of other 2,6-dicarboxylic acid ester-4-pyrone compounds (a2-a25) are shown in Table 1.

[0070]

[0071] Table 1 2,6-dicarboxylate-4-pyrone compounds shown in formula I

[0072]

[0073]

[0074]

[0075]

[0076] Preparation of catalyst components

[0077] Example 1

[0078] This embodiment provides a catalyst component, and the preparation method thereof is as follows:

[0079] In a 500 ml 5-necked flask with nitrogen fully replaced and stirred, 10 g of MgCl2·2.5C2H5OH microspheres and 150 mL of titanium tetrachloride were added to prepare a suspension, then maintained at -15°C for 1 hour, slowly heated to 80°C, 3 g (10 mmol) of 2,6-di-n-butyl dicarboxylate-4-pyrone was added, and the temperature was continued to rise to 110°C and kept constant for 1 hour, then the liquid was filtered clean, and the obtained solid was washed 3 times with 120 mL of titanium tetrachloride at 110°C, and then washed 4 times with 150 mL of hexane at 60°C, the liquid was filtered off and dried to obtain a solid catalyst component E1. The titanium content, internal electron donor content and polymerization data of the solid catalyst component are shown in Table 2.

[0080] Example 2-25

[0081] Examples 2-25 each provide a catalyst component E2-E25, the preparation process of which is as shown in Example 1, except that 2,6-di-n-butyl dicarboxylate-4-pyrone is replaced with 10 mmol of compounds a2-a25 in Table 1 in sequence.

[0082] Embodiment 26

[0083] This embodiment provides a catalyst component, and the preparation method thereof is as follows:

[0084] In a 500ml 5-necked flask with nitrogen fully replaced and stirred, add 10g anhydrous magnesium chloride, 150mL toluene, 17mL epichlorohydrin and 16mL tributyl phosphate at room temperature, heat to 50℃ with stirring, and maintain for 2 hours, the solid is completely dissolved, then add 2.40g phthalic anhydride and maintain for another hour. Cool the solution to -25℃, add 110mL titanium tetrachloride dropwise within 1 hour, slowly heat to 80℃, and gradually wash out the solid during the heating process. Add 3g 2,6-di-n-butyl-4-pyrone dicarboxylate, maintain at 80℃ for 1 hour; after filtering, wash twice with 200mL toluene, then add 120mL toluene and 80mL titanium tetrachloride, continue to heat to 110℃, keep the temperature for 2 hours, then filter the liquid clean, and repeat the process once. The liquid was filtered off, and the obtained solid was washed once with 100 mL of dichloroethane and four times with hexane, and then dried to obtain solid catalyst component E26. The titanium content, internal electron donor content and polymerization data of the solid catalyst component are shown in Table 2.

[0085] Embodiment 27

[0086] This embodiment provides a catalyst component, and the preparation method thereof is as follows:

[0087] In a 500ml 5-necked flask with nitrogen fully replaced and stirred, 8g of diethoxymagnesium and 100mL of toluene were added to prepare a suspension, 25mL of titanium tetrachloride was added dropwise at -15°C, the temperature was slowly raised to 0°C after the addition was completed, and 50mL of titanium tetrachloride was added dropwise, and then the temperature was slowly raised to 80°C, 2.5g of 2,6-di-n-butyl dicarboxylate-4-pyrone was added, and the temperature was continued to rise to 110°C and kept constant for 2 hours, and then the liquid was filtered clean, the liquid was filtered off, and the obtained solid was washed 3 times with 100mL of titanium tetrachloride at 125°C. The obtained solid was washed 4 times with 120mL of hexane at 60°C, the liquid was filtered off and dried to obtain the solid catalyst component E27.

[0088] Comparative Example 1

[0089] This comparative example provides a catalyst component D1, and its preparation process is the same as that of Example 1, except that 2,6-di-n-butyl dicarboxylate-4-pyrone is replaced by 10 mmol of di-n-butyl phthalate (DN).

[0090] Comparative Example 2

[0091] This comparative example provides a catalyst component D2, and its preparation process is the same as that of Example 1, except that 2,6-di-n-butyl dicarboxylate-4-pyrone is replaced by 10 mmol of 9,9-dimethoxyfluorene (FLU).

[0092] polymerization

[0093] The solid catalyst component obtained above was used as a component of an olefin polymerization catalyst to carry out polymerization evaluation:

[0094] After nitrogen is fully replaced in a 5L stainless steel reactor, 5mL of 0.5mol / L triethylaluminum hexane solution and 1mL of 0.1mol / L methylcyclohexyldimethoxysilane hexane solution and 10mg of the prepared catalyst are added, and then 10mL of hexane is added to flush the feed line, and then 2L (under standard conditions) of hydrogen and 2.5L of refined propylene are added, and the reaction is controlled to prepolymerize at 25°C for 5 minutes, and the temperature is raised to 70°C, and the polymerization reaction is carried out at this temperature for 1 hour. After the reaction is completed, the reactor is cooled and stirring is stopped, the reaction product is discharged, and the polymer is obtained by drying. The polymerization data is shown in Table 2.

[0095] Table 2

[0096]

[0097]

[0098] As can be seen from Table 2, the catalysts of Examples 1-25 containing different substituents as internal electron donors of 2,6-dicarboxylic acid ester-4-pyrone compounds are all more active than the catalyst of the phthalate internal electron donor of Comparative Example 1 under the same preparation conditions, and are higher than the diether catalyst of Comparative Example 2, and have good stereoselectivity, high isotacticity of the obtained polymer, and moderate molecular weight distribution. The catalyst has regular particle size and high bulk density. Examples 26 and 27 are catalysts prepared by using 2,6-di-n-butyl dicarboxylate-4-pyrone using different preparation methods, and also show excellent performance of high activity and high stereoselectivity.

Claims

1. A catalyst component for olefin polymerization, comprising: Mg, Ti, halogen, 2,6-dicarboxylate-4-pyrone internal electron donors; in, The 2,6-dicarboxylate-4-pyrone internal electron donor has a structure shown in Formula I: In Formula I, R 1 , R 2 , R 3 and R 4 are the same or different, each independently selected from H, halogen, C1-C 20 The hydrocarbon group; Preferably, R 1 , R 2 , R 3 and R 4 Each of the heteroatoms comprises one or a combination of two or more selected from N, O, S, P, Si and halogen; Preferably, R 1 , R 2 , R 3 and R 4 Two or more of them are bonded to each other to form a ring.

2. The catalyst component according to claim 1, wherein In Formula I, R 1 , R 2 , R 3 and R 4 the same or different, each independently selected from H, halogen, the following substituents with less than 20 carbon atoms: straight-chain or branched alkyl, cycloalkyl, alkenyl, ester, phenyl, alkylphenyl, phenylalkyl, indenyl, benzyl, halogenated alkyl, alkyl containing heteroatoms, halogenated cycloalkyl, cycloalkyl containing heteroatoms, halogenated phenyl, phenyl containing heteroatoms, halogenated alkylphenyl, alkylphenyl containing heteroatoms, halogenated phenylalkyl, phenylalkyl containing heteroatoms, halogenated indenyl, indenyl containing heteroatoms, halogenated benzyl, benzyl containing heteroatoms, heterocyclic aromatic substituents; the heteroatoms include one or a combination of two or more of N, O, S, P, and Si.

3. The catalyst component according to claim 2, wherein In Formula I, R 1 , R 2 , R 3 and R 4 are each independently selected from H, halogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, cyclopentyl, n-hexyl, cyclohexyl, heptyl, octyl, nonyl, decyl, C 11 -C 20 a straight-chain or branched alkyl group having less than 20 carbon atoms, or the following substituents: alkenyl, phenyl, m-chlorophenyl, p-chlorophenyl, o-chlorophenyl, m-methoxyphenyl, p-methoxyphenyl, o-methoxyphenyl, p-methylphenyl, p-nitrophenyl, m-nitrophenyl, benzyl and its derivatives, phenethyl and its derivatives, furyl, pyrrolyl, thienyl, indenyl; Preferably, R 1 , R 2 Each is independently selected from phenyl and its derivatives, more preferably a halogenated phenyl group.

4. The catalyst component according to claim 1, wherein The 2,6-dicarboxylate-4-pyrone internal electron donor includes 2,6-dicarboxylic acid di-n-butyl ester-4-pyrone, 2,6-dicarboxylic acid diethyl ester-4-pyrone, 2,6-dicarboxylic acid diisobutyl ester-4-pyrone, 2,6-dicarboxylic acid dicyclohexyl ester-4-pyrone, 2,6-dicarboxylic acid di(tetradecyl) ester-4-pyrone, 2,6-dicarboxylic acid diphenyl ester-4-pyrone, 2,6-dicarboxylic acid diphenylethyl ester-4-pyrone. , 2,6-dicarboxylic acid di-m-chlorophenyl ester-4-pyrone, 2,6-dicarboxylic acid di-p-chlorophenyl ester-4-pyrone, 2,6-dicarboxylic acid di-o-chlorophenyl ester-4-pyrone, 2,6-dicarboxylic acid di-p-methylphenyl ester-4-pyrone, 2,6-dicarboxylic acid di-m-methoxyphenyl ester-4-pyrone, 2,6-dicarboxylic acid di-p-methoxyphenyl ester-4-pyrone, 2,6-dicarboxylic acid di-o-methoxyphenyl ester-4-pyrone, 2,6-dicarboxylic acid di-(α- Furan methyl ester)-4-pyrone, 2,6-dicarboxylic acid di (5-pentenyl)-4-pyrone, 2,6-dicarboxylic acid di-p-nitrophenyl ester-4-pyrone, 2,6-dicarboxylic acid di-n-butyl ester-4-pyrone, 2,6-dicarboxylic acid di-n-butyl ester-3,5-dimethyl-4-pyrone, 2,6-dicarboxylic acid diethyl ester-3-phenyl-4-pyrone, 2,6-dicarboxylic acid diethyl ester-3-chloro-4-pyrone, 2,6-dicarboxylic acid diethyl ester- 3-bromo-4-pyrone, 2,6-diisopropyl dicarboxylate-4-pyrone, 2,6-dibenzyl dicarboxylate-4-pyrone, 2-ethyl carboxylate-6-n-butyl carboxylate-4-pyrone, 2-n-butyl ethyl carboxylate-6-phenyl carboxylate-4-pyrone, 2,6-dicarboxylate-3-methyl-4-pyrone, 2,6-dicarboxylate-di-n-butyl-3-methyl-5-ethyl-4-pyrone, or a combination of two or more thereof.

5. The catalyst component according to any one of claims 1 to 4, wherein The catalyst component comprises a titanium compound, a magnesium compound, and the 2,6-dicarboxylate-4-pyrone internal electron donor; The precursor of the magnesium compound is selected from X n Mg(OR a ) 2-n 、MgCl2·mR a OH, R a 2-n MgX n , MgCl2 / SiO2, MgCl2 / Al2O3, a mixture of magnesium halide and titanium alkoxide, or a combination of two or more thereof, wherein m is 0.1-6, 0≤n≤2, X is a halogen, R a C1-C 20 The hydrocarbon group; The general formula of the titanium compound is TiX N (OR b ) 4-N , where R b C1-C 20 The hydrocarbon group is: X is halogen, and N is 1-4.

6. The catalyst component according to claim 5, wherein The magnesium compound is an alcoholate of magnesium dihalide; Alternatively, the magnesium compound is a liquid magnesium compound; Alternatively, the magnesium compound is a derivative of a magnesium dihalide molecule in which at least one halogen atom is replaced by a hydrocarbonoxy group or a halogenated hydrocarbonoxy group; preferably, it is a hydrocarbonoxy magnesium compound; more preferably, it is an alkoxy magnesium and / or an aryloxy magnesium.

7. The catalyst component according to claim 5, wherein The titanium compound includes one or a combination of two or more of titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, and alkoxy titanium halide; Preferably, the alkyl titanium halide includes one or a combination of two or more of methoxytitanium trichloride, ethoxytitanium trichloride, propoxytitanium trichloride, n-butoxytitanium trichloride, dimethoxytitanium dichloride, diethoxytitanium dichloride, dipropoxytitanium dichloride, di-n-butoxytitanium dichloride, trimethoxytitanium chloride, triethoxytitanium chloride, tripropoxytitanium chloride, and tri-n-butoxytitanium chloride; Preferably, the titanium compound is titanium tetrachloride.

8. The catalyst component according to claim 5, wherein The feeding molar ratio of the 2,6-dicarboxylate-4-pyrone internal electron donor to the magnesium compound is 0.01-5.0:1, preferably 0.05-3.0:1, and the magnesium compound is calculated as magnesium element.

9. A catalyst for olefin polymerization, comprising the catalyst component according to any one of claims 1 to 8 and an organic aluminum compound.

10. The catalyst according to claim 9, wherein The general formula of the organoaluminum compound is AlR c p X (3-p) , where R c is hydrogen or C1-C 20 A hydrocarbon group, X is a halogen, and p is an integer of 0≤p≤3; Preferably, the organoaluminum compound comprises one or a combination of two or more of trialkylaluminum compounds, alkylaluminum halides, alkylaluminum hydrides, alkylaluminum sesquichlorides, and alkylaluminoxanes; Preferably, the trialkylaluminum compound includes one or a combination of two or more of trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri-n-hexylaluminum, and trioctylaluminum; the alkylaluminum halide includes AlEt2Cl; and the alkylaluminum sesquichloride includes Al2Et3Cl3.

11. The catalyst according to claim 9, wherein The molar ratio of the organic aluminum compound to the titanium atom in the catalyst component is 1-1000:1, preferably 50-800:

1.

12. The catalyst according to claim 9, wherein The raw material composition of the catalyst also includes an external electron donor.

13. The catalyst according to claim 12, wherein The external electron donor is a siloxane compound.

14. The catalyst according to claim 13, wherein The general formula of the siloxane compound is R' t Si(OR”) 4-t , wherein R' and R" are each independently selected from C1-C 18 A hydrocarbon group, t is an integer of 0≤t≤3; Preferably, said R' and R" each contain a heteroatom; Preferably, the heteroatom includes one or a combination of two or more of N, O, S, P and Si.

15. The catalyst according to claim 12, wherein The molar ratio of silicon in the external electron donor to titanium in the catalyst component is 0.002-100:1, preferably 0.01-20:1, and more preferably 0.01-5:

1.

16. Use of the catalyst according to any one of claims 9 to 15 in olefin polymerization; Preferably, the olefin includes one or a combination of two or more of ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 3-methyl-1-butene, 4-methyl-1-pentene, butadiene, vinylcyclopentene, and vinylcyclohexene; Preferably, the polymerization comprises ethylene and / or propylene polymerization; Preferably, the polymerization comprises homopolymerization or copolymerization.

17. The use according to claim 16, wherein: The polymerization temperature is ≤200°C, preferably 20-100°C, more preferably 40-80°C; The polymerization pressure is ≤10 MPa, preferably 0.3-5 MPa.

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