A catalyst component for olefin polymerization, the catalyst, and its application.

Abstract

This invention provides a catalyst component, a catalyst, and its application for olefin polymerization. The catalyst component comprises Mg, Ti, halogens, and kojic acid ester internal electron donors. The kojic acid ester internal electron donors have the structure shown in Formula I. This catalyst component and catalyst exhibit high catalytic activity and high biosafety, and can reduce the total ash content of polypropylene resin, catalyst residues, and the toxicity of the residues. It is particularly suitable for the production of medical polypropylene materials.

Description

Technical Field

[0001] This invention relates to a solid catalyst component for olefin polymerization, its preparation method and application, belonging to the field of polyolefin catalysts. Background Technology

[0002] Polypropylene (PP) possesses excellent properties, such as radiation resistance, high heat resistance, high pressure resistance, biodegradability, good mechanical properties, and chemical stability, leading to its increasingly widespread application in the medical field. In medicine, PP is primarily used for medical nonwoven fabrics, disposable medical products, medical transparent tubing, blood filters, and artificial lungs. When used to manufacture disposable medical products, syringes, catheters, and other medical devices, PP offers advantages such as lightweight, durability, high temperature resistance, non-toxicity, ease of processing, low cost, and prevention of iatrogenic cross-infection during use. However, the hygiene performance indicators of ordinary PP do not meet the standards for producing medical products, limiting its application.

[0003] One of the challenges in producing medical-grade clean polypropylene lies in the extremely high requirements for ash control. The total ash content of polypropylene resin and residual catalyst components are key indicators of concern in clean polypropylene production. If clean polypropylene is not obtained directly in the washing reactor using a process, highly active catalysts are often required. To fundamentally improve the properties of the active centers of Ziegler-Natta catalysts (ZN catalysts) and significantly enhance polymerization activity, internal electron donors are added during catalyst preparation, while external electron donors are added during polymerization. Both have a significant impact on olefin polymerization behavior and polymer properties. Among these, altering the internal electron donors in the catalyst can maximally change the properties of the active centers, thereby maximizing the modification of catalyst performance.

[0004] The development of novel electron donors has always been a hot topic in the research and development of Zn polypropylene catalysts. Among the existing technologies, the most distinctive high-performance internal electron donor compounds are: (1) fatty acid esters and aromatic esters, mainly phthalate compounds; (2) diether compounds (e.g., compounds disclosed in EP0361493 and EP0728724); (3) succinate compounds (e.g., compounds disclosed in WO9856834, WO0063261, and WO03022894); (4) glycol ester compounds (e.g., compounds disclosed in WO9856834, WO0063261, and WO03022894); and (5) compounds with other functional groups (e.g., compounds disclosed in CN1105671, CN1242780, and US20060128558), etc. However, in practical applications, the above-mentioned compounds all have certain problems as internal electron donors for olefin polymerization catalysts. Although catalysts using 1,3-diether compounds as internal electron donors have high activity and good hydrogen-modulated sensitivity, the relative molecular mass distribution of the synthesized PP is narrow, which is not conducive to the development of different grades of PP. Succinate compounds as internal electron donors have the advantage of producing PP with a wider relative molecular mass distribution, but the stereoregularity of PP and the hydrogen-modulated sensitivity of the catalyst need to be improved. The activity of glycol ester catalytic systems is generally not as ideal as that of diether systems.

[0005] Currently, phthalate compounds are the most widely used internal electron donors in polyolefin industry. Catalysts prepared from phthalates exhibit moderate activity, good stereoselectivity, and low cost. However, as commonly used plasticizers, phthalates pose significant risks to human reproductive health and the environment, creating a substantial demand for alternatives. The use of most phthalate compounds has already been restricted. To improve the performance of polyolefin catalysts, internal electron donor compounds constitute approximately 5-20% by weight in solid catalysts. However, as residual components in polymerization, they negatively impact the cleanliness of polypropylene. This is especially true when using catalysts containing high amounts of phthalate internal electron donors, which can leave residual components with a certain degree of reproductive toxicity in the polypropylene, limiting its medical applications. Furthermore, lower catalyst activity requires larger amounts of catalyst during polymerization, resulting in more residues and making it less suitable for the production of medical-grade polypropylene. Therefore, developing catalysts containing highly biosafe internal electron donor compounds with high activity will benefit the production of medical-grade polypropylene products and promote the development of medical-grade polypropylene materials. Summary of the Invention

[0006] To address the aforementioned problems, the present invention aims to provide a catalyst component, a catalyst, and its application for olefin polymerization. This catalyst component and catalyst exhibit high catalytic activity and high biosafety, and can reduce the toxicity of residual catalyst components, making them particularly suitable for the production of medical polypropylene materials.

[0007] To achieve the above objectives, the present invention provides a catalyst component for olefin polymerization, comprising: Mg, Ti, halogen, and kojic acid ester internal electron donor; wherein the kojic acid ester internal electron donor has the structure shown in Formula I:

[0008]

[0009] In Equation I, R 1 R 2 R 3 and R 4 Whether the elements are the same or different, they are each independently selected from H, halogens, and C1-C. 20 The hydrocarbon group; preferably, R 1 R 2 R 3 and R 4 Each contains heteroatoms selected from one or more combinations of halogens, N, O, S, P, and Si; preferably, R 1 R 2 R 3 and R 4 Two or more bonds in a ring are formed.

[0010] According to a specific embodiment of the present invention, preferably, in formula I, R 1 R 2 R 3 and R 4 The substituents, whether identical or different, are independently selected from H, halogens, and the following substituents with 20 or fewer carbon atoms: straight-chain or branched alkyl, cycloalkyl, alkenyl, ester, phenyl, alkylphenyl, phenylalkyl, indene, benzyl, haloalkyl, heteroatom-containing alkyl, halocycloalkyl, heteroatom-containing cycloalkyl, halophenyl, heteroatom-containing phenyl, haloalkylphenyl, heteroatom-containing alkylphenyl, halophenylalkyl, heteroatom-containing phenylalkyl, haloindenyl, heteroatom-containing indene, halobenzyl, heteroatom-containing benzyl, heterocyclic aryl substituents; the heteroatoms include one or more combinations of N, O, S, P, and Si.

[0011] According to a specific embodiment of the present invention, preferably, in formula I, R 1 R 2 R 3 and R 4Each is 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 following substituents with 20 or fewer carbon atoms, whether linear or branched alkyl groups: 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, furanyl, pyrroleyl, thiophenyl, indene; more preferably, the alkenyl group includes propenyl, butenyl, pentenyl, and hexenyl.

[0012] According to a specific embodiment of the present invention, preferably, in formula I, R 1 and R 2 Selected from C1-C 20 hydrocarbon group; R 3 and R 4 All are H.

[0013] According to a specific embodiment of the present invention, preferably, the electron donor in the kojic acid ester class includes kojic acid diacetate, kojic acid dipropionate, kojic acid di-n-butyrate, kojic acid diisobutyrate, kojic acid di-n-valerate, kojic acid diisovalerate, kojic acid di-tert-valerate, kojic acid di-n-hexanoate, kojic acid diisohexanoate, kojic acid dicyclopentylcarboxylate, kojic acid di-n-heptanoate, kojic acid dicyclohexylcarboxylate, kojic acid di-octanoate, kojic acid di-nonanoate, kojic acid di-decanoate, kojic acid di(undecanoate), kojic acid dilaurate, kojic acid dimyristate, kojic acid dipalmitate, and kojic acid distearate. Kojic acid dibenzoate, kojic acid diphenylacetate, kojic acid diphenylpropionate, kojic acid di-o-chlorobenzoate, kojic acid di-m-chlorobenzoate, kojic acid di-p-toluene ester, kojic acid di-p-methoxybenzoate, kojic acid m-trimethylbenzoate, kojic acid p-nitrobenzoate, kojic acid p-fluorobenzoate, kojic acid p-trifluoromethylbenzoate, kojic acid dicrotonate, kojic acid di(1-naphthoic acid) ester, kojic acid dinicotinate, kojic acid di(monoethyl succinate) ester, kojic acid dicinnamate, kojic acid di(α-thiophene) carboxylate, and kojic acid difurylate are one or more combinations of these.

[0014] The kojic acid ester compounds shown in Formula I can be synthesized by methods including, but not limited to, the following: prepared by a one-step reaction of kojic acid with an acyl chloride, as shown in Formula I. Various acyl chlorides can be commercially available products, or prepared by reacting the corresponding substituents of an acid with thionyl chloride.

[0015]

[0016] According to a specific embodiment of the present invention, preferably, the catalyst component comprises a titanium compound, a magnesium compound, and the kojic acid ester 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 One or more combinations of MgCl2 / SiO2, MgCl2 / Al2O3, magnesium halides, and titanium alkoxides, wherein m is 0.1-6, 0≤n≤2, X is a halogen, and R a For C1-C 20 The hydrocarbon group; the general formula of the titanium compound is TiX. N (OR b ) 4-N In the formula, R b For C1-C 20 The hydrocarbon group, where X is a halogen and N is 1-4.

[0017] According to a specific embodiment of the present invention, preferably, the magnesium compound is an alkoxide 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 in which at least one halogen atom in a magnesium dihalide molecule is replaced by an alkyl group or a halogenated alkyl group; more preferably, it is an alkyloxy magnesium compound; and even more preferably, it is alkoxy magnesium and / or aryloxy magnesium.

[0018] 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 titanium alkoxyhalides.

[0019] According to a specific embodiment of the present invention, preferably, the alkyl titanium halide includes one or more of titanium methoxytrichloride, titanium ethoxytrichloride, titanium propoxytrichloride, titanium n-butoxytrichloride, titanium dimethoxydichloride, titanium diethoxydichloride, titanium dipropoxydichloride, titanium dibutoxydichloride, titanium dibutoxydichloride, titanium trimethoxytrichloride, titanium triethoxytrichloride, titanium tripropoxydichloride, and titanium dibutoxydichloride; more preferably, the titanium compound is titanium tetrachloride.

[0020] According to a specific embodiment of the present invention, preferably, the molar ratio of the kojic acid ester internal electron donor to the magnesium compound calculated as magnesium element is 0.01-5.0:1, more preferably 0.05-3.0:1.

[0021] The present invention does not specifically limit the preparation method of the above-mentioned solid catalyst components, which can be carried out according to the following listed methods:

[0022] Method 1: A magnesium alkoxide or magnesium chloroalkoxide, excess TiCl4, and an internal electron donor compound are reacted at a temperature of 80-135°C; preferably, a compound of the general formula TiX can be used. N (OR b ) 4-N Titanium compounds (where R) b For C1-C 20 The hydrocarbon group, where X is a halogen and N = 1-4; preferably TiCl4) and the general formula MgCl2·mR a The adduct of OH (where m is a number from 0.1 to 6, preferably 2 to 4, and R) a For C1-C 20 Solid catalyst components are prepared by reacting hydrocarbon groups (or internal electron donors); wherein the general formula is MgCl2·mR a The OH adduct can be suitably prepared into spherical form by mixing an alcohol and magnesium chloride in the presence of an inert hydrocarbon immiscible with the adduct, followed by rapid quenching of the emulsion, thereby solidifying the adduct into spherical particles (see disclosures in US4399054 and US4469648). The spherical adduct obtained by this method can react directly with titanium compounds, or it can be pre-treated with a thermally controlled dealcoholization process (80-130°C) to obtain a dealcoholization adduct (wherein the molar number of alcohol is generally less than 3, preferably between 0.1 and 2.5), before proceeding with subsequent reactions.

[0023] For example, the adduct or dealcohol adduct is suspended in cold TiCl4 (generally -25 to 0°C) to react with a titanium compound, and the mixture is heated to 80 to 130°C and held at this temperature for 0.5 to 2 hours. The treatment with TiCl4 can be performed once or multiple times, and an internal electron donor compound can be added during the TiCl4 treatment. This treatment can be repeated once or multiple times.

[0024] Method 2: A magnesium compound is dissolved in a solvent system consisting of an organic epoxy compound, an organophosphorus compound, and an inert diluent to form a homogeneous solution. This solution is then mixed with a titanium compound, and a solid is precipitated in the presence of a precipitation aid. This solid is treated with an internal electron-donating compound to load the compound onto the solid. If necessary, further treatment with titanium tetrahalide and an inert diluent is performed. The precipitation aid is one of organic anhydrides, organic acids, ethers, or ketones. The components, per mole of magnesium halide, are: organic epoxy compound 0.2-10 mol, organophosphorus compound 0.1-3 mol, precipitation aid 0-1.0 mol, and Ti compound 0.5-150 mol (based on moles of titanium).

[0025] Method 3: React a TiCl4 or hydroxyl-titanium aromatic hydrocarbon solution (e.g., toluene, xylene, etc.) with a dialkoxymagnesium compound such as magnesium (preferably diethoxymagnesium) or diaryloxymagnesium at -25℃ to 0℃, and halogenate at 80-130℃. This treatment with the TiCl4 aromatic hydrocarbon solution can be repeated once or multiple times, and an internal electron donor compound can be 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 as follows: Add magnesium ethoxy, tetraethoxytitanium, o-cresol, ethanol and chlorobenzene sequentially, and stir; quickly add a TiCl4 / chlorobenzene solution to the above liquid, heat until completely dissolved, and continue heating to a specific temperature; use N2 to bubble away the ethanol reactants and continue stirring for a certain period of time, then wash once with hot chlorobenzene, wash twice with isooctane, and then dry with N2 to obtain the support. Alternatively, as in another example: TiCl4, tetraethoxytitanium, ethoxymagnesium and o-cresol are added to chlorobenzene in sequence and stirred; ethanol is added, and after the ethoxymagnesium dissolves at high temperature, stirring is continued for 3 hours; the mixture is filtered while hot, then washed once with warm chlorobenzene, once with isooctane, and finally dried with N2.

[0026] Method 4: Magnesium dichloride is pre-activated using existing methods, and then treated with excess TiCl4 at approximately 80-135°C, wherein the solution contains an internal electron-donating compound. The solid is treated with TiCl4 multiple times and washed with hexane to remove any unreacted TiCl4.

[0027] Method 5: Prepare the titanium-containing solid catalyst component according to the preparation method disclosed in CN1208045: First, contact the liquid magnesium compound and the liquid titanium compound 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. During the contact process, treat with an internal electron donor compound.

[0028] Method Six: Anhydrous magnesium chloride and an internal electron donor compound are co-milled under conditions where magnesium dichloride is activated. The resulting product can be treated once or multiple times with excess TiCl4 at a temperature of 80-130°C, followed by washing with a hydrocarbon solvent until chloride ions are removed. A more detailed method involves co-milling anhydrous magnesium dichloride, a titanium compound, and an internal electron donor compound, followed by treatment with a haloalkane such as 1,2-dichloroethane, chlorobenzene, or dichloromethane for 1-4 hours at a temperature between 40°C and the boiling point of the haloalkane. The product is then typically washed with an inert hydrocarbon solvent such as hexane.

[0029] Method 7: Magnesium compounds supported on inorganic oxides such as SiO2, alumina, or porous silica gel are used as supports for preparation. The mixture is then activated using well-known methods and treated with an excess of TiCl4 at a temperature of approximately 80-135°C. During the treatment process, an internal electron donor compound is added.

[0030] The reaction of the above-mentioned catalyst components leads to the formation of magnesium halides in an active form. Typical crystalline magnesium halides have a regular structure and can support very little Ti, resulting in low catalytic activity. To prepare highly active supported catalysts, magnesium halides must undergo activation treatment. Activation methods include using physical and / or chemical methods to prepare them into microcrystals so that active centers are supported on the surface, edges, and defects of the magnesium halide. These treated magnesium halide microcrystals suitable for supporting Ti are called "activated magnesium halides." Besides these reactions, other methods are known in the literature to form magnesium halides in an active form from starting materials different from magnesium halides.

[0031] In any method for preparing the catalyst component, the aforementioned internal electron donor compound can be added directly or optionally, for example, in situ prepared using a suitable precursor that can be converted in the desired internal electron donor compound via known chemical reactions such as esterification or transesterification. Typically, the aforementioned internal electron donor compound is used at a molar ratio of 0.01-5:1, preferably 0.05-3.0:1, relative to the molar number of MgCl2. Furthermore, the internal electron donor compound can be added simultaneously or separately during the preparation process, either in batches or in any order and combination.

[0032] The present invention also provides a catalyst for olefin polymerization, the composition of which includes the above-described catalyst components and an organoaluminum compound.

[0033] According to a specific embodiment of the present invention, preferably, the organoaluminum compound has the general formula AlR c p X (3-p) , where R c It is hydrogen or C1-C 20 The hydrocarbon group, X is a halogen, and p is an integer 0 ≤ p ≤ 3.

[0034] According to a specific embodiment of the present invention, preferably, the organoaluminum compound includes one or more of the following: trialkylaluminum compound, alkylaluminum halide, alkylaluminum hydride, alkylaluminum sesquichloride, and alkylaluminoxane.

[0035] According to a specific embodiment of the present invention, preferably, the trialkylaluminum compound includes one or more of trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri-n-hexylaluminum, and trioctylaluminum; the alkylaluminum halide includes AlEt2Cl; the alkylaluminum sesquichloride includes Al2Et3Cl3; more preferably, the organoaluminum compound is a mixture of AlEt2Cl and Al2Et3Cl3.

[0036] According to a specific embodiment of the present invention, preferably, the molar ratio of the organoaluminum compound to the titanium atoms in the catalyst component is 1-1000:1, more preferably 50-800:1.

[0037] According to a specific embodiment of the present invention, preferably, the raw material composition of the catalyst further includes an external electron donor.

[0038] According to a specific embodiment of the present invention, preferably, the external electron donor is a siloxane compound.

[0039] According to a specific embodiment of the present invention, preferably, the general formula of the siloxane compound is R'. t Si(OR”) 4-t In this context, R' and R” are each independently selected from C1-C 18 The hydrocarbon group, where t is an integer of 0 ≤ t ≤ 3; more preferably, R' and R” respectively contain heteroatoms; more preferably, the heteroatoms include one or more combinations of N, O, S, P, and Si.

[0040] 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, diisobutyldimethoxysilane, di-tert- ... Silane, di-tert-butyldiethoxysilane, di-n-butyldiethoxysilane, n-butylmethyldimethoxysilane, di(2-ethylhexyl)dimethoxysilane, di(2-ethylhexyl)diethoxysilane, dicyclohexyldimethoxysilane, dicyclohexyldiethoxysilane, dicyclohexyldimethoxysilane, dicyclopentyldimethoxysilane, dicyclopentyldiethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, cyclohexylethyldimethoxysilane, cyclohexylisopropyldimethoxysilane, cyclohexylethyldiethoxysilane, cyclopentylmethyldimethoxysilane, cyclopentylethyldiethoxysilane, cyclopentylisopropyldiethoxysilane, cyclopentylisobutyldimethoxysilane, cyclohexyl-n-propyl Dimethoxysilane, cyclohexyl-n-propyldiethoxysilane, cyclohexyl-n-butyldiethoxysilane, pentylmethyldimethoxysilane, pentylmethyldiethoxysilane, pentylethyldimethoxysilane, pentylethyldiethoxysilane, cyclohexyldimethylmethoxysilane, cyclohexyldiethylmethoxysilane, cyclohexyldiethylmethoxysilane, cyclohexyldiethylethoxysilane, 2-ethylhexyltrimethoxysilane, cyclohexyldimethoxysilane, cyclohexyldiethoxysilane, 2-ethylhexyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane, n-butyl 2-Ethylhexyltrimethoxysilane, 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,One or more combinations of 5-dimethylcyclohexylcyclopentyldimethoxysilane, 3-methylcyclohexylcyclohexyldimethoxysilane, di(3-methylcyclohexyl)dimethoxysilane, 4-methylcyclohexylcyclohexyldimethoxysilane, di(4-methylcyclohexyl)dimethoxysilane, 3,5-dimethylcyclohexylcyclohexyldimethoxysilane, di(3,5-dimethylcyclohexyl)dimethoxysilane, tetrapropoxysilane, and tetrabutoxysilane.

[0041] 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, cyclohexylmethyl dimethoxysilane, and cyclohexylethyl diethoxysilane. One or more combinations of cyclohexylethyldimethoxysilane, cyclohexylethyldiethoxysilane, cyclopentylmethyldimethoxysilane, cyclopentylmethyldiethoxysilane, cyclopentylethyldimethoxysilane, cyclohexylcyclopentyldimethoxysilane, cyclohexylcyclopentyldiethoxysilane, 3-methylcyclohexylcyclopentyldimethoxysilane, 4-methylcyclohexylcyclopentyldimethoxysilane, and 3,5-dimethylcyclopentyldimethoxysilane.

[0042] According to a specific embodiment of the present invention, preferably, the siloxane compound includes one or more combinations of 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)-methyldimethoxysilane, cyclohexyltrimethoxysilane, tert-butyltrimethoxysilane, and tert-hexyltrimethoxysilane.

[0043] 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 even more preferably 0.01-5:1.

[0044] The present invention also provides the application of the above-mentioned catalyst in olefin polymerization.

[0045] According to a specific embodiment of the present invention, preferably, the olefin comprises straight-chain or branched olefins, 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, and vinylcyclohexene, or a combination of two or more of these.

[0046] According to a specific embodiment of the present invention, preferably, the polymerization includes ethylene and / or propylene polymerization.

[0047] According to a specific embodiment of the present invention, preferably, the polymerization includes homopolymerization or copolymerization.

[0048] According to a specific embodiment of the present invention, preferably, the order of adding the components in the catalyst during the catalytic process is arbitrary, with the organoaluminum compound being added to the polymerization system first, followed by the external electron donor, and finally the catalyst components.

[0049] According to a specific embodiment of the present invention, preferably, in the above applications, the polymerization process can be carried out with or without a solvent; the olefin monomer can be in the 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 processes can be applied, and the polymerization reaction can be carried out in one step, two steps or multiple steps.

[0050] According to a specific embodiment of the present invention, preferably, the polymerization temperature is ≤200℃, more preferably 20-100℃, and even more preferably 40-80℃; the polymerization pressure is ≤10MPa, more preferably 0.3-5MPa.

[0051] Kojic acid esters are food, pharmaceutical, and cosmetic additives with antibacterial, preservative, and skin-brightening properties. In food processing, they can be used as food additives to prevent spoilage, preserve freshness, and provide antioxidant effects. They can also be used to preserve fresh flowers, vegetables, and fruits, improving their appearance and internal quality and extending shelf life. In cosmetics, kojic acid esters are known for their significant skin-brightening effects, safety, and widespread application in the treatment of pigmentation disorders.

[0052] This invention utilizes various kojic acid ester compounds as internal electron donors in the preparation of olefin polymerization catalysts, resulting in catalysts with high activity and selectivity. Some of the kojic acid ester compounds are commercially available food and pharmaceutical additives, while other non-commercial kojic acid ester compounds can be prepared by a one-step reaction of appropriate acyl chlorides with kojic acid. This method has low production costs, and the wide range of acyl chloride substituents allows for optimization of the internal electron donor structure through screening various substituents to further improve catalyst performance, making it particularly suitable for industrial applications.

[0053] Kojic acid esters contain various oxygen-containing functional groups such as ketones, ethers, and esters on their six-membered ring skeleton. They have multiple electron-donating groups that play a positive regulating role in the active center of the catalyst, thereby improving catalytic activity and reducing catalyst residue in polypropylene. Kojic acid ester compounds have high stability and no side effects on the human body. As catalysts with internal electron donors, they are particularly suitable for the production of medical polypropylene with high requirements for cleanliness and biotoxicity. Detailed Implementation

[0054] In order to provide a clearer understanding of the technical features, objectives and beneficial effects of the present invention, the technical solution of the present invention will now be described in detail below, but it should not be construed as limiting the scope of implementation of the present invention.

[0055] In the following examples, the preparation of the catalyst was carried out under the protection of high-purity nitrogen.

[0056] The isotacticity of polymers was determined by the heptane extraction method (boiling heptane extraction for 6 hours): two grams of dry polymer sample were placed in an extractor and extracted with boiling heptane for 6 hours. The residue was then dried to constant weight. The ratio of the obtained polymer weight (g) to 2 is the isotacticity.

[0057] The bulk density of the polymer was determined using the method specified in JB / T 2412-2008.

[0058] The molecular weight distribution of the polymer was determined by PL-220 gel permeation chromatography at 150 °C with trichlorobenzene as solvent (standard: polystyrene, flow rate 1.0 mL / min, column: 3xPlgel 10um M1Xed-B300x7.5nm).

[0059] Preparation example: Synthesis of kojic acid ester compounds represented by Formula I

[0060] 1. The synthesis of kojic acid distearate follows these steps:

[0061] 13.5 g of dried kojic acid (0.095 mol) was dissolved in 270 mL of dried pyridine. The mixture was stirred vigorously at 20 °C, and stearyl chloride was rapidly added dropwise at a rate of 10 mL / min. The mixture was cooled with a coolant. After the addition was complete, the temperature was gradually raised to about 30 °C, and the mixture was kept at this temperature and stirred thoroughly for 2 hours to obtain a uniform pale yellow reactant. The reaction product was added to 10 times its volume of distilled water and stirred until homogeneous. The mixture was centrifuged and filtered. The filter cake was washed with a large amount of distilled water until there was no pyridine odor (pyridine wastewater was recycled). The crude product was dissolved in a mixture of 400 mL of ethyl acetate and 10 g of activated carbon. The mixture was heated to reflux and stirred for 20 min to decolorize. The mixture was filtered while hot to remove the activated carbon, resulting in a pale yellow solution. The solution was cooled to room temperature to obtain crystals. The crystals were filtered and washed 2-3 times with cold ethyl acetate. The filter cake was dried thoroughly at 70 °C to remove water and ethyl acetate, yielding kojic acid distearate, with a yield of 80%.

[0062] 2. Other kojic acid ester compounds (a2-a25) were prepared using the above-described route, with the starting materials selected from acyl chlorides and kojic acid with corresponding substituents. The structures and NMR results of compounds a2-a25 are shown in Table 1.

[0063]

[0064] Table 1 shows the kojic acid ester compounds of Formula I.

[0065]

[0066]

[0067]

[0068] Preparation of catalyst components

[0069] Example 1

[0070] This embodiment provides a catalyst component, the preparation method of which is as follows:

[0071] In a 500 mL stirred flask equipped with a stirrer and fully purged with nitrogen, 10 g of MgCl2·2.5C2H5OH microspheres and 150 mL of titanium tetrachloride were added to prepare a suspension. The suspension was then maintained at -15 °C for one hour, and the temperature was slowly increased to 80 °C. 3.1 g (5 mmol) of kojic acid distearate was added, and the temperature was further increased to 110 °C and held for one hour. The liquid was then filtered clean. The resulting solid was washed three times with 120 mL of titanium tetrachloride at 110 °C, and then washed four times with 150 mL of hexane at 60 °C. The liquid was filtered off and dried to obtain solid catalyst component E1. The titanium content, internal electron donor content, and polymerization data of this solid catalyst component are shown in Table 2.

[0072] Example 2-25

[0073] Examples 2-25 each provide a solid catalyst component E2-E25, the preparation process of which is as shown in Example 1, except that kojic acid distearate is replaced with 5 mmol of compounds a2-a25 in Table 1 in sequence.

[0074] Example 26

[0075] This embodiment provides a catalyst component E26, the preparation method of which is as follows:

[0076] In a 500 mL stirred flask equipped with a stirrer and fully purged with nitrogen, 10 g of anhydrous magnesium chloride, 150 mL of toluene, 17 mL of epichlorohydrin, and 16 mL of tributyl phosphate were added at room temperature. The mixture was heated to 50 °C with stirring and maintained for 2 hours until the solid was completely dissolved. Then, 2.40 g of phthalic anhydride was added, and the temperature was maintained for another hour. The solution was cooled to -25 °C, and 110 mL of titanium tetrachloride was added dropwise over 1 hour. The temperature was slowly raised to 80 °C, and the solid was gradually washed away during the heating process. 3.1 g of kojic acid distearate was added, and the temperature was maintained at 80 °C for 1 hour. After filtration, the solution was washed twice with 200 mL of toluene. Then, 120 mL of toluene and 80 mL of titanium tetrachloride were added, and the temperature was further raised to 110 °C and maintained for 2 hours. The liquid was then filtered clean, and the process was repeated once more. The liquid was filtered off, and the resulting solid was washed once with 100 mL of dichloroethane and four times with hexane. After drying, solid catalyst component E26 was obtained. The titanium content, internal electron donor content, and polymerization data of the solid catalyst components are shown in Table 2.

[0077] Example 27

[0078] This embodiment provides a catalyst component E27, the preparation method of which is as follows:

[0079] In a 500 ml stirred flask equipped with nitrogen purging, 8 g of magnesium diethoxy and 100 mL of toluene were added to prepare a suspension. 25 mL of titanium tetrachloride was added dropwise at -15 °C. After the addition was complete, the temperature was slowly raised to 0 °C, and 50 mL of titanium tetrachloride was added dropwise. The temperature was then slowly raised to 80 °C, and 3.1 g of kojic acid distearate was added. The temperature was then raised to 110 °C and held for 2 hours. The liquid was then filtered clean, and the liquid was discarded. The resulting solid was washed three times with 100 mL of titanium tetrachloride at 125 °C, and then washed four times with 120 mL of hexane at 60 °C. The liquid was then filtered off and dried to obtain solid catalyst component E27.

[0080] Comparative Example 1

[0081] This comparative example provides a catalyst component D1, which is prepared in the same manner as in Example 1, except that kojic acid distearate is replaced with 5 mmol of di-n-butyl phthalate (DN).

[0082] Comparative Example 2

[0083] This comparative example provides a catalyst component D2, which is prepared in the same way as in Example 1, except that kojic acid distearate is replaced with 5 mmol of 9,9-dimethoxyfluorene (FLU).

[0084] Comparative Example 3

[0085] This comparative example provides a catalyst component D3, which is prepared in the same way as in Example 1, except that kojic acid distearate is replaced with 5 mmol of acetyl tributyl citrate.

[0086] polymerization

[0087] The solid catalyst components obtained above were used as components for olefin polymerization catalysts for polymerization evaluation:

[0088] After the 5L stainless steel reactor was fully purged with nitrogen, 5 mL of 0.5 mol / L triethylaluminum hexane solution, 1 mL of 0.1 mol / L methylcyclohexyldimethoxysilane hexane solution, and 10 mg of the prepared catalyst component were added. Then, 10 mL of hexane was added to flush the feed line, followed by 2 L (under standard conditions) of hydrogen and 2.5 L of purified propylene. The reaction was prepolymerized at 25°C for 5 minutes, then the temperature was raised to 70°C, and polymerization was carried out at this temperature for 1 hour. After the reaction was completed, the reactor was cooled and stirring was stopped. The reaction product was discharged and dried to obtain the polymer. The polymerization data are shown in Table 2.

[0089] Table 2

[0090]

[0091]

[0092] The kojic acid ester compounds in Examples 1-25, acting as internal electron donors, exhibited significantly higher activity than catalysts using acetylated tributyl citrate (a biosafety-associated additive) as an internal electron donor under the same preparation conditions. Their activity was also higher than that of the most commonly used phthalate internal electron donor catalyst in industry (polymer number 28). This demonstrates that kojic acid ester compounds can serve as a highly efficient alternative to reproductively toxic phthalate internal electron donors. Furthermore, fluorene diether catalysts, due to their high activity, are currently frequently used in the development of low-ash polyolefin products. The kojic acid ester compounds in Examples 1-25 of this invention exhibited comparable activity to fluorene diether catalysts (polymer number 29), with some examples showing even higher activity. Therefore, the kojic acid ester internal electron donors of this invention demonstrate high biosafety, and the prepared catalysts exhibit high activity, making them particularly suitable for the production of medical-grade polypropylene products.

Claims

1. A catalyst component for olefin polymerization, comprising: Internal electron donors of Mg, Ti, halogens, and kojic acid esters; in, The kojic acid ester internal electron donor has the structure shown in Formula I: Formula I, In Equation I, R 1 R 2 R 3 and R 4 Whether the elements are the same or different, they are each independently selected from H, halogens, and C1-C. 20 The hydrocarbon group, or the following substituents with 20 or fewer carbon atoms: ester group, haloalkyl group, heteroatom-containing alkyl group, halocycloalkyl group, heteroatom-containing cycloalkyl group, halophenyl group, heteroatom-containing phenyl group, haloalkylphenyl group, heteroatom-containing alkylphenyl group, halophenylalkyl group, heteroatom-containing phenylalkyl group, haloindenyl group, heteroatom-containing indenyl group, heterocyclic aryl substituent; the heteroatom includes one or more combinations of N, O, S, P, and Si.

2. The catalyst component according to claim 1, wherein, In Equation I, R 1 R 2 R 3 and R 4 Whether the substituents are the same or different, each is independently selected from H, halogens, and the following substituents with up to 20 carbon atoms: straight-chain or branched alkyl, cycloalkyl, alkenyl, phenyl, alkylphenyl, phenylalkyl, indenyl.

3. The catalyst component according to claim 1, wherein, In Equation I, R 1 R 2 R 3 and R 4 Each is 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 Straight-chain or branched alkyl groups, and the following substituents with 20 or fewer carbon atoms: alkenyl, phenyl, m-chlorophenyl, p-chlorophenyl, o-chlorophenyl, m-methoxyphenyl, p-methoxyphenyl, o-methoxyphenyl, p-methylphenyl, p-nitrophenyl, m-nitrophenyl, benzyl, phenethyl, furanyl, pyrroleyl, thiophenyl, indene.

4. The catalyst component according to claim 1, wherein, In Equation I, R 1 and R 2 Selected from C1-C 20 hydrocarbon group; R 3 and R 4 All are H.

5. The catalyst component according to claim 1, wherein, The electron donors in the kojic acid ester class include diacetate kojic acid, dipropionate kojic acid, di-n-butyrate kojic acid, diisobutyrate kojic acid, di-n-valerate kojic acid, diisovalerate kojic acid, di-tert-valerate kojic acid, di-n-hexanoate kojic acid, diisohexanoate kojic acid, dicyclopentyl kojic acid, di-n-heptanoate kojic acid, dicyclohexyl kojic acid, dioctanoate kojic acid, dinonanoate kojic acid, didecanoate kojic acid, di(undecanoate) kojic acid, dilaurate kojic acid, dimyristic acid, dipalmitate kojic acid, distearate kojic acid, and dibenzoate kojic acid. Kojic acid diphenylacetate, kojic acid diphenylpropionate, kojic acid di-o-chlorobenzoate, kojic acid di-m-chlorobenzoate, kojic acid di-p-toluene ester, kojic acid di-p-methoxybenzoate, kojic acid m-trimethylbenzoate, kojic acid p-nitrobenzoate, kojic acid p-fluorobenzoate, kojic acid p-trifluoromethylbenzoate, kojic acid dicrotonate, kojic acid di(1-naphthoic acid) ester, kojic acid dinicotinate, kojic acid di(monoethyl succinate) ester, kojic acid dicinnamate, kojic acid di(α-thiophene) carboxylate, and kojic acid difurylate are one or more of the following.

6. The catalyst component according to any one of claims 1-5, wherein, The catalyst component comprises titanium compounds, magnesium compounds, and the kojic acid ester 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 One or more combinations of MgCl2 / SiO2, MgCl2 / Al2O3, magnesium halides, and titanium alkoxides, wherein m is 0.1-6, 0≤n≤2, X is a halogen, and R a For C1-C 20 hydrocarbon group; The general formula of the titanium compound is TiX. N (OR b ) 4-N In the formula, R b For C1-C 20 The hydrocarbon group, where X is a halogen and N is 1-4.

7. The catalyst component according to claim 6, wherein, The magnesium compound is an alkoxide of magnesium dihalide; Alternatively, the magnesium compound may be a liquid magnesium compound; Alternatively, the magnesium compound is a derivative in which at least one halogen atom in a magnesium dihalide molecule is replaced by a hydrocarbon oxygen atom.

8. The catalyst component according to claim 7, wherein, The magnesium compound is an alkyl oxymagnesium compound.

9. The catalyst component according to claim 7, wherein, The magnesium compound is alkoxymagnesium and / or aryloxymagnesium.

10. The catalyst component according to claim 6, wherein, The titanium compound includes one or more of titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, and titanium alkoxyhalides.

11. The catalyst component according to claim 10, wherein, The alkoxy titanium halide includes one or more combinations of methoxy titanium trichloride, ethoxy titanium trichloride, propoxy titanium trichloride, n-butoxy titanium trichloride, dimethoxy titanium dichloride, diethoxy titanium dichloride, dipropoxy titanium dichloride, di-n-butoxy titanium dichloride, trimethoxy titanium chloride, triethoxy titanium chloride, tripropoxy titanium chloride, and tri-n-butoxy titanium chloride.

12. The catalyst component according to claim 10, wherein, The titanium compound is titanium tetrachloride.

13. The catalyst component according to claim 6, wherein, The molar ratio of the electron donor in the kojic acid ester to the magnesium compound is 0.01-5.0:1, and the magnesium compound is calculated based on magnesium element.

14. The catalyst component according to claim 13, wherein, The molar ratio of the electron donor in the kojic acid ester to the magnesium compound is 0.05-3.0:

1.

15. A catalyst for olefin polymerization, comprising the catalyst component as described in any one of claims 1-13 and an organoaluminum compound.

16. The catalyst according to claim 15, wherein, The general formula of the organoaluminum compound is AlR c p X (3-p) , where R c It is hydrogen or C1-C 20 The hydrocarbon group, X is a halogen, and p is an integer 0 ≤ p ≤ 3.

17. The catalyst according to claim 16, wherein, The organoaluminum compounds include one or more of trialkylaluminum compounds and alkylaluminum halides.

18. The catalyst according to claim 17, wherein, The trialkylaluminum compound includes one or more of trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri-n-hexylaluminum, and trioctylaluminum; the alkylaluminum halide includes AlEt2Cl.

19. The catalyst according to claim 15, wherein, The organoaluminum compound is a mixture of AlEt2Cl and Al2Et3Cl3.

20. The catalyst according to claim 15, wherein, The molar ratio of the organoaluminum compound to the titanium atoms in the catalyst component is 1-1000:

1.

21. The catalyst according to claim 20, wherein, The molar ratio of the organoaluminum compound to the titanium atoms in the catalyst component is 50-800:

1.

22. The catalyst according to claim 15, wherein, The catalyst's feedstock composition also includes an external electron donor.

23. The catalyst according to claim 22, wherein, The external electron donor is a siloxane compound.

24. The catalyst according to claim 23, wherein, The general formula of the siloxane compound is R' t Si(OR'') 4-t Where R' and R'' are each independently selected from any C1-C containing heteroatoms. 18 The hydrocarbon group, where t is an integer 0 ≤ t ≤ 3.

25. The catalyst according to claim 24, wherein, The heteroatoms include one or more combinations of N, O, S, P, and Si.

26. The catalyst according to claim 23, wherein, The molar ratio of silicon in the external electron donor to titanium in the catalyst component is 0.002-100:

1.

27. The catalyst according to claim 26, wherein, The molar ratio of silicon in the external electron donor to titanium in the catalyst component is 0.01-20:

1.

28. The catalyst according to claim 27, wherein, The molar ratio of silicon in the external electron donor to titanium in the catalyst component is 0.01-5:

1.

29. The use of the catalyst according to any one of claims 15-28 in olefin polymerization.

30. The application according to claim 29, wherein, The olefins include one 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.

31. The application according to claim 30, wherein, The polymerization includes the polymerization of ethylene and / or propylene.

32. The application according to claim 29, wherein, The polymerization includes homopolymerization or copolymerization.

33. The application according to claim 29, wherein, The polymerization temperature is ≤200℃. The polymerization pressure is ≤10MPa.

34. The application according to claim 33, wherein, The polymerization temperature is 20-100℃, and the polymerization pressure is 0.3-5MPa.

35. The application according to claim 34, wherein, The polymerization temperature is 40-80℃.

Images