Catalyst component

Abstract

The present invention relates to components useful in propylene polymerization catalysts, and particularly provides a solid hydrocarbon insoluble catalyst component containing magnesium, titanium and halogen and further comprising a modifier compound having the structure (1): # imgabs0 # wherein R1 is selected from H, aryl or alkyl groups having 1 to 10 carbon atoms, R2 is selected from alkyl groups having 1 to 10 carbon atoms, and R3 is selected from alkyl groups having 1 to 10 carbon atoms. R3 to R6 are each independently selected from H, alkylaryl, aryl or an alkyl group having 1 to 10 carbon atoms and halogen, with the proviso that at least one of R4 and R5 is H, any alkylaryl, aryl or alkyl group optionally comprises one or more heteroatoms and / or optionally wherein R3 and R4 or R5 and R6 are linked to form a cyclic group.

Description

[0001] The present invention relates to components that can be used in catalysts, and particularly to modifier components used in combination with magnesium-containing supported titanium-containing catalyst components.

[0002] The use of solid transition metal-based olefin polymerization catalyst components is well known in the art, including such solid components supported on metal oxides, halides, or other salts, such as the widely described magnesium-containing titanium halide-based catalyst components. Although many polymerization and copolymerization methods and catalyst systems for polymerizing or copolymerizing α-olefins have been described, it would be advantageous to tailor the methods and catalyst systems to obtain a specific set of properties of the resulting polymer or copolymer product. For example, in certain applications, a combination of high activity, good morphology, desired particle size distribution, acceptable bulk density, etc., as well as polymer characteristics such as stereospecificity, molecular weight distribution, etc., is required.

[0003] Typically, supported catalyst components that can be used for polymerizing propylene and higher carbon α-olefins and that can be used for polymerizing propylene and higher carbon olefins with small amounts of ethylene and other α-olefins contain an electron donor component as an internal modifier. Such an internal modifier is an integral part of the solid supported component and is different from any external electron donor component, and together with an alkylaluminum component, it can constitute a catalyst system. Typically, the combination is contacted with an olefin monomer either shortly after combining a cocatalyst such as an alkylaluminum and any external electron donor with the solid catalyst component, or the cocatalyst such as an alkylaluminum and any external electron donor is combined with the solid catalyst component in the presence of the olefin monomer.

[0004] The choice of internal modifier and other electron donor components can affect catalyst performance and the resulting polymer formed. A large number of organic electron donors have been described as being useful for preparing stereospecific supported catalyst components, including organic compounds containing oxygen, nitrogen, sulfur, and / or phosphorus. Such compounds include organic acids, organic acid anhydrides, organic acid esters, alcohols, ethers, aldehydes, ketones, amines, amine oxides, amides, thiols, various phosphoric acid esters and amides, etc. Mixtures of organic electron donors have been described as being useful for incorporation into supported catalyst components. Specific examples of organic electron donors commonly used as internal modifiers include dicarboxylic acid esters, such as alkyl phthalates, succinates, and other bidentate donors, such as diether.

[0005] It is also known that, in addition to the cocatalyst, the external donor component of the catalyst can include several components. For example, WO2005 / 30815 and WO 2009 / 85649 describe propylene polymerization catalysts that, in addition to one or more aluminum-containing cocatalysts, also include a combination of external donors, particularly a combination of at least one alkoxysilane referred to as a "selectivity control agent" (SCA) and at least one aliphatic or cycloaliphatic mono- or poly-carboxylic acid or its ester derivative referred to as an "activity limiter" (ALA).

[0006] In addition, many individual methods or method steps have been disclosed for producing improved supported magnesium, titanium, and electron donor-containing olefin polymerization or copolymerization catalysts. For example, US 4866022 discloses a method for forming a favorable α-olefin polymerization or copolymerization catalyst or catalyst component, which involves a specific sequence of individual method steps. US 4540679 discloses a method for preparing alkyl magnesium carbonate by reacting a suspension of magnesium alkoxide in alcohol with carbon dioxide and reacting the alkyl magnesium carbonate with a transition metal component. US 4612299 discloses a method for preparing magnesium carboxylate by reacting a solution of an alkyl magnesium compound with carbon dioxide to precipitate magnesium carboxylate and reacting the magnesium carboxylate with a transition metal component.

[0007] The specific use of the polymer that can be produced depends on the physical properties of the polymer, such as molecular weight, viscosity, stiffness, flexural modulus, and polydispersity index (molecular weight distribution (M w / M n ))). Additionally, the morphology of the polymer or copolymer generally depends on the morphology of the catalyst.

[0008] The present invention relates to catalyst components and catalysts, particularly catalysts containing a novel modifier component.

[0009] Accordingly, in a first aspect, the present invention provides a hydrocarbon-insoluble solid catalyst component containing magnesium, titanium, and halogen and further comprising a modifier compound having structure (1):

[0010]

[0011] wherein

[0012] R 1 is selected from H, aryl, or an alkyl group having 1 to 10 carbon atoms,

[0013] R 2 is selected from alkyl groups having 1 to 10 carbon atoms,

[0014] R 3 to R 6 are each independently selected from H, alkylaryl, aryl, or an alkyl group having 1 to 10 carbon atoms, and halogen, provided that at least one of R 4 and R 5 is H

[0015] Any alkylaryl, aryl, or alkyl group optionally contains one or more heteroatoms and / or optionally R 3 and R 4 or R 5 and R 6 are linked to form a cyclic group.

[0016] The catalyst component, in combination with a cocatalyst, is particularly useful as a catalyst for olefin polymerization.

[0017] Accordingly, in a second aspect, the present invention also provides a catalyst useful for polymerizing olefins, the catalyst comprising:

[0018] (i) a solid catalyst component insoluble in hydrocarbons, the component containing magnesium, titanium and halogen and further comprising a modifier compound having structure (1):

[0019]

[0020] wherein

[0021] R 1 is selected from H, aryl or an alkyl group having 1 to 10 carbon atoms,

[0022] R 2 is selected from alkyl groups having 1 to 10 carbon atoms,

[0023] R 3 to R 6 are each independently selected from H, alkylaryl, aryl or an alkyl group having 1 to 10 carbon atoms and halogen, provided that at least one of R 4 and R 5 is H,

[0024] any alkylaryl, aryl or alkyl group optionally contains one or more heteroatoms and / or optionally wherein R 3 and R 4 or R 5 and R 6 are linked to form a cyclic group; and

[0025] (ii) at least one cocatalyst component.

[0026] For the avoidance of doubt, the modifier is an electron donor compound and may also be regarded as an electron donor compound. The claimed modifier can be used as an external electron donor in the first and second aspects of the present invention, but is used as an internal electron donor in a preferred embodiment, or specifically an "internal modifier".

[0027] (As used herein, the term "modifier" is used as a shorthand expression for referring to the modifier compound of structure (1), and the terms "modifier" and "modifier compound" may be used interchangeably. The term "modifier" is used in the present invention to clearly distinguish the modifier of structure (1) from other electron donors that may be present in any aspect or embodiment.)

[0028] As used in this context, the terms "internal" and "external" are well understood in the art. Generally, and as used herein, the term "internal", when used to refer to a modifier (or other electron donor), refers to a compound that is an integral part of the solid-supported catalyst component. Typically, this is achieved by adding the internal modifier (or other electron donor) during the catalyst preparation process. In contrast, the term "external", when used to refer to a modifier (or other electron donor), refers to a compound that either contacts the combination shortly after combining it with the other parts of the solid catalyst component or is combined with the other parts of the solid catalyst component in the presence of an olefin monomer, such as in a reactor.

[0029] In the present invention:

[0030] R 1 is selected from H (hydrogen), aryl, or an alkyl group having 1 to 10 carbon atoms,

[0031] R 2 is selected from alkyl groups having 1 to 10 carbon atoms, and

[0032] R 3 to R 6 are each independently selected from H (hydrogen), alkylaryl, aryl, or an alkyl group having 1 to 10 carbon atoms, and halogen, provided that at least one of R 4 and R 5 is H.

[0033] Any alkylaryl, aryl, or alkyl group present may optionally contain one or more heteroatoms. Optionally, R 3 and R 4 may be linked to form a cyclic group. Optionally, R 5 and R 6 may be linked to form a cyclic group.

[0034] R 1 is selected from hydrogen, aryl, or an alkyl group having 1 to 10 carbon atoms. Preferably, R 1 does not contain any heteroatoms. It is also preferred that R 1 is not linked to any of the groups of R 2 to R 6 to form a cyclic group (i.e., is not linked to other groups other than as shown in structure (1)). R 1 is preferably selected from hydrogen, aryl, or an alkyl group having 1 to 6 carbon atoms. When R 1 is an aryl group, it is preferably a phenyl group. R 1 is more preferably selected from hydrogen and alkyl groups having 1 to 6 carbon atoms. Most preferably, R 1Selected from hydrogen, methyl, ethyl, and propyl, such as selected from hydrogen and methyl. Most preferably, R 1 is hydrogen.

[0035] R 2 is selected from alkyl groups having 1 to 10 carbon atoms. Preferably, R 2 does not contain any heteroatoms. Also preferably, R 2 is not connected to R 1 and R 3 to R 6 to form a cyclic group (i.e., not connected to other groups except as shown in structure (1)). R 2 is preferably selected from alkyl groups having 1 to 6 carbon atoms. More preferably, R 2 is selected from methyl, ethyl, propyl, and butyl, most preferably methyl, ethyl, and butyl.

[0036] R 3 to R 6 are each independently selected from hydrogen, alkylaryl, aryl, or alkyl groups having 1 to 10 carbon atoms, and halogen, provided that at least one of R 4 and R 5 is H. R 3 to R 6 which are alkylaryl, aryl, or alkyl groups having 1 to 10 carbon atoms preferably do not contain heteroatoms (i.e., if R 3 to R 6 themselves are not halogen, then they do not contain heteroatoms). Optionally, R 3 and R 4 can be connected to form a cyclic group. Optionally, R 5 and R 6 can be connected to form a cyclic group. (It should be noted that since at least one of R 4 and R 5 is H, if R 3 and R 4 are connected to form a cyclic group, then R 5 must be H, and R 5 and R 6 cannot be connected to form a cyclic group in the same structure, and vice versa.)

[0037] In the first embodiment, R 3 to R 6 are each hydrogen. In three particularly preferred structures according to this embodiment, R 1 is also hydrogen, and R 2 is an alkyl selected from methyl, ethyl, or butyl, respectively. In a further preferred structure according to this embodiment, R 1 and R 2are both methyl. In a further preferred structure according to this embodiment, R 1 is phenyl and R 2 is methyl.

[0038] In the second embodiment, at least one of R 3 to R 6 is a halogen. In this embodiment, it is preferred that R 5 is a halogen, and most preferably bromine. (And in this case, obviously R 4 must be H.) In a preferred structure, R 5 is a halogen, most preferably bromine, while each of R 3 , R 4 and R 6 is hydrogen. Most preferably, R 1 is hydrogen, R 2 is methyl, R 3 , R 4 and R 6 are each hydrogen, R 5 is a halogen, and in a particularly preferred structure according to this embodiment, most preferably bromine.

[0039] In the third embodiment, at least one of R 3 to R 6 is an alkyl group and preferably has 1 to 6 carbon atoms. In this embodiment, it is also possible that at least one of R 3 to R 6 can be a halogen. However, this is not preferred. Preferably, at least two of R 3 to R 6 are hydrogen, that is, at most two of R 3 to R 6 are alkyl groups. In a preferred option, at least one of R 3 and R 5 is an alkyl group. In a particularly preferred structure according to this option, R 1 is hydrogen, R 2 is methyl, R 3 and R 5 are tert-butyl groups, and R 4 and R 6 are each hydrogen. In another preferred option, at least R 6 is an alkyl group. In a particularly preferred structure according to this option, R 1 is hydrogen, R 2 is butyl, R 3 to R 5 are each hydrogen, and R 6 is methyl.

[0040] As previously mentioned, optionally R3 and R 4 or R 5 and R 6 may be connected to form a cyclic group. In many of the preferred alternative embodiments disclosed above, R 3 and R 4 do not connect to form a cyclic group and R 5 and R 6 do not connect to form a cyclic group. In these embodiments, it is generally more preferred that none of R 1 to R 6 is connected to any other group among R 1 to R 6 to form a cyclic group (i.e., there is no cyclic group other than the aromatic ring of structure (1)).

[0041] In the case where there is a cyclic group (other than the aromatic ring of structure (1)), it is most preferred that R 3 and R 4 are connected to form the cyclic group. In this case, R 5 is H. It is also preferred that in this case, none of R 1 , R 2 and R 6 is connected to any other group among R 1 , R 2 and R 6 or to the group formed by R 3 and R 4 (i.e., there are no more cyclic groups).

[0042] In this embodiment, a particularly preferred structure is the following structure (2):

[0043]

[0044] wherein

[0045] R 1 , R 2 and R 6 are as defined above,

[0046] R 5 is H, and

[0047] R 7 to R 10 are each independently selected from H, alkylaryl, aryl or an alkyl group having 1 to 6 carbon atoms, and halogen, and the alkylaryl, aryl and alkyl groups optionally contain one or more heteroatoms.

[0048] R 1 , R 2 and R 6Preferably as defined previously for structure (1).

[0049] R 7 to R 10 are each independently selected from hydrogen, alkylaryl, aryl or an alkyl group having 1 to 6 carbon atoms, and halogen, and the alkylaryl, aryl and alkyl groups optionally contain one or more heteroatoms. Preferably R 7 to R 10 do not contain heteroatoms (most preferably, none of R 1 , R 2 and R 6 to R 10 contains any heteroatoms).

[0050] Also preferably in this structure (2), none of R 1 , R 2 and R 6 to R 10 is connected to any other group among R 1 , R 2 and R 6 to R 10 (i.e., there are no more cyclic groups).

[0051] Preferably, R 7 to R 10 are each independently selected from hydrogen and an alkyl group having 1 to 6 carbon atoms, more preferably selected from hydrogen, methyl, ethyl and propyl. Most preferably R 7 to R 10 are each hydrogen.

[0052] In a preferred structure according to structure (2), R 2 is ethyl, and R 1 and R 5 to R 10 are all hydrogen.

[0053] More generally in the present invention, and although not preferred, any one of the alkylaryl, aryl or alkyl groups may be substituted by a heteroatom. Examples include oxygen, sulfur, nitrogen, phosphorus, silicon or halogen. For example, the alkyl groups used in the present invention may be substituted by nitrogen in the form of an amine group, by nitrogen and oxygen in the form of an amide group, or by chlorine, bromine or a silyl group. The cyclic alkyl or aryl structures may contain heteroatoms such as oxygen, sulfur, nitrogen, silicon and phosphorus.

[0054] As described previously, except in the case where one or more of R 3 to R 6 are halogen, preferably none of R 1 to R 6 in structure (1) or R 1, R 2 or R 6 to R 10 None of which contains a heteroatom, i.e., they contain only H atoms or only C and H atoms.

[0055] In a preferred embodiment, the modifier (particularly one of the aforementioned preferred modifiers) is present as an internal modifier in the catalyst component.

[0056] It should also be noted that mixtures of modifier compounds described by structure (1) and mixtures of such compounds with other donor compounds known in the art can be used. Examples thereof are further described below. (For the avoidance of doubt, the reference herein to compounds of structure (1) also includes "subsets" of such compounds described by structure (2), even if the structure is not directly mentioned. This is because the compounds of structure (2) are also compounds according to structure (1).)

[0057] The solid catalyst component insoluble in hydrocarbons generally comprises a titanium compound supported on a magnesium compound, in combination with a modifier compound. In a preferred embodiment, when the modifier is an internal modifier, the supported titanium-containing olefin polymerization catalyst component is generally formed by reacting a titanium compound, a modifier compound, and a magnesium compound. Optionally, such a supported titanium-containing reaction product can be further processed or modified by further chemical treatment.

[0058] Suitable magnesium compounds include magnesium halides; reaction products of magnesium halides such as magnesium chloride or magnesium bromide with organic compounds such as alcohols or organic acid esters or with organometallic compounds of metals of Groups I-III; magnesium alkoxides; or alkylmagnesiums.

[0059] A particularly preferred titanium compound for such steps is TiCl4, but many other species such as other titanium(IV) halides or titanium alkoxides are known to be suitable.

[0060] The present invention is not limited to catalyst components prepared by any particular preparation method.

[0061] For example, a catalyst component containing an internal modifier can be prepared by reacting magnesium and titanium compounds and a modifier compound in any suitable order. For example, a catalyst component can be prepared by first reacting magnesium and titanium compounds and then incorporating a modifier compound. Alternatively, the modifier can be incorporated before, during, or (in multiple steps) in combination with the titanium compound.

[0062] Generally, the aforementioned modifier compound and titanium compound can be contacted with solid particles of the magnesium compound in the presence of an inert hydrocarbon or a halogenated diluent, but other suitable techniques can also be employed. Suitable diluents are substantially inert to the components employed and are liquid at the temperatures and pressures employed.

[0063] Most commonly, one or more solutions of titanium tetrachloride and modifier compounds are contacted with a magnesium-containing material, for example by addition to a slurry of magnesium-containing particles in a suitable hydrocarbon. Such magnesium-containing materials are typically in the form of discrete particles and may contain other materials such as transition metals and organic compounds. Additionally, a mixture of magnesium chloride, titanium tetrachloride, and a modifier can be formed into an active catalyst component by ball milling.

[0064] However, in a preferred method, a slurry of the magnesium-containing material is first contacted with a solution of the modifier, typically with stirring. The resulting solution is then treated with a suitable titanium-containing species. Several steps can be applied to add an internal donor or titanium or both.

[0065] In a particularly advantageous procedure, magnesium chloride-based carrier particles suspended in a liquid hydrocarbon diluent such as toluene are first contacted with titanium tetrachloride and then with a modifier compound, these two contacting steps being repeated one or more times, followed by a final contacting step with titanium tetrachloride (i.e., no subsequent step of adding more modifier). The diluent used can be decanted between steps and fresh diluent added before the next step. After the final step, the diluent is removed, the product is washed one or more times with a liquid hydrocarbon such as heptane, and then dried.

[0066] The conditions in such steps are known in the art. These steps are typically carried out at elevated temperatures, usually 75 to 135 °C, and at normal pressure or slightly elevated pressure of 1 to 3 bar. The typical individual treatment time for each step can vary from a few minutes to several hours, usually 0.25 to 3 hours.

[0067] As a result of the preparation steps, a solid reaction product suitable for use as a catalyst or catalyst component is obtained. Prior to such use, it is desirable to remove unreacted starting materials from the solid reaction product. This is conveniently achieved by washing the solid with a suitable solvent such as a liquid hydrocarbon or a chlorocarbon after separation from any preparation diluent, preferably within a short time after completion of the preparation reaction, since prolonged contact between the catalyst component and unreacted starting materials can adversely affect the performance of the catalyst component.

[0068] Although not essential, the final solid reaction product can be washed with an inert liquid hydrocarbon or a halogenated hydrocarbon prior to contact with a Lewis acid. If such washing is carried out, it is preferred to substantially remove the inert liquid before contacting the washed solid with the Lewis acid.

[0069] In a typical catalyst component of the present invention, the molar ratio of magnesium to titanium is at least 1:1, preferably at most 20:1. Larger amounts of magnesium can be employed without adversely affecting the performance of the catalyst component, but a ratio of magnesium to titanium exceeding 20:1 is generally not required. More preferably, the ratio of magnesium to titanium is in the range of 2:1 to 20:1, such as 5:1 to 20:1.

[0070] The catalyst component of the present invention generally contains 1 to 6 weight percent of titanium, 10 to 25 weight percent of magnesium, and 45 to 65 weight percent of halogen. Preferably, the catalyst component contains 2 to 4 weight percent of titanium, 15 to 21 weight percent of magnesium, and 55 to 65 weight percent of chlorine.

[0071] When used as an internal modifier, the modifier component is typically incorporated into the solid catalyst component at a molar ratio of modifier to titanium of at least 0.1:1 and / or at most 10:1. This molar ratio is preferably at least 0.2:1, more preferably at least 0.4:1. This molar ratio is preferably at most 5:1, such as at most 2:1. A molar ratio of modifier to titanium in the range of 0.4:1 to 1.2:1 is most preferred.

[0072] As previously mentioned, in one embodiment of the present invention, mixtures of electron donors can be used. This includes mixtures of two or more modifier compounds described by structure (1) and mixtures of such compounds with other electron donor compounds known in the art.

[0073] For example, when using a modifier of structure (1) as an internal modifier (internal electron donor), the modifier can be used as a component of an internal donor mixture. Preferably, in these embodiments, the internal donor mixture is a mixture of at least one compound of structure (1) and at least one other electron donor compound known in the art (hereinafter referred to as "additional internal donor").

[0074] In one embodiment, the additional internal donor can be a dialkyl phthalate. For example, the additional internal donor can be a dialkyl phthalate in which each alkyl group can be the same or different and contains 3 to 5 carbon atoms, preferably dibutyl phthalate, more preferably di-n-butyl phthalate or diisobutyl phthalate. Alternatively, the additional internal donor can be a dialkyl phthalate in which each alkyl group can be the same or different and each contains at least 6 carbon atoms, preferably at most 10 (carbon) atoms. Suitable specific dialkyl phthalates include dihexyl phthalate and dioctyl phthalate.

[0075] In an alternative, the additional internal donor can be a dicycloaliphatic ester of an aromatic dicarboxylic acid, where each cycloaliphatic moiety can be the same or different and each contains 5 to 7 carbon atoms, preferably 6 carbon atoms. Preferably, the ester is a dicycloaliphatic diester of an o-aromatic dicarboxylic acid. Specific dicycloaliphatic esters that are suitable include dicyclopentyl phthalate, dicyclohexyl phthalate, and bis(methylcyclopentyl) phthalate.

[0076] In another alternative, the additional internal donor can be an alkyl-arylalkyl phthalate, where the alkyl moiety contains 2 to 10, preferably 3 to 6 carbon atoms, and the arylalkyl moiety contains 7 to 10, preferably up to 8 carbon atoms. In particular, suitable alkyl-arylalkyl phthalates include benzyl n-butyl phthalate and benzyl isobutyl phthalate.

[0077] In addition, the additional internal donor can be an alkyl ester of an aliphatic monocarboxylic acid, where the carboxylic acid moiety contains 2 to 20, preferably 3 to 6 carbon atoms, and the alkyl moiety contains 1 to 3 carbon atoms. Preferably, the additional internal donor is an alkyl ester of an aliphatic monocarboxylic acid. Specific alkyl esters that are suitable include methyl valerate, ethyl pivalate, methyl pivalate, methyl butyrate, and ethyl propionate.

[0078] In another alternative, such an additional internal donor can also be an alkyl ester of an aromatic monocarboxylic acid, where the monocarboxylic acid moiety contains 6 to 8 carbon atoms and the alkyl moiety contains 1 to 3 carbon atoms. Specific alkyl esters that are suitable in this case include methyl toluate, ethyl toluate, methyl benzoate, ethyl benzoate, and propyl benzoate.

[0079] In yet another alternative, the additional internal donor can also be a 1,3-diether, particularly a 2,2-disubstituted-1,3-diether. Preferred examples include 2-isopropyl-2-isobutyl-1,3-dimethoxypropane, 2,2-diisobutyl-1,3-dimethoxypropane, 2-isopropyl-2-isopentyl-1,3-dimethoxypropane, 2,2-dicyclohexyl-1,3-dimethoxypropane, 2,2-bis(cyclohexylmethyl)-1,3-dimethoxypropane, and 9,9-bis(methoxymethyl)fluorene. Among these, 2-isopropyl-2-isobutyl-1,3-dimethoxypropane, 2-isopropyl-2-isopentyl-1,3-dimethoxypropane, and 9,9-bis(methoxymethyl)fluorene are preferred.

[0080] In all of the above alternatives, the molar ratio of the additional internal donor to the (internal) modifier can be, for example, in the range of 5:95 to 95:5.

[0081] The catalyst or catalyst component of the present invention can be used in the polymerization or copolymerization of α-olefins. The prepolymerization or encapsulation of the catalyst or catalyst component can be carried out before being used in the polymerization. A particularly useful prepolymerization procedure is described in US 4579836.

[0082] Generally, the catalyst component of the present invention is combined with a cocatalyst component for polymerization. The cocatalyst component can be a Group II or Group III metal alkylide. The available Group II and Group IIIA metal alkylides are compounds of the formula MR m where M is a Group II or Group III metal, each R is independently an alkyl group having 1 to 20 carbon atoms, and m corresponds to the valence of M. Examples of available metals M include magnesium, calcium, zinc, cadmium, aluminum, and gallium. Examples of suitable alkyl groups R include methyl, ethyl, butyl, hexyl, decyl, tetradecyl, and eicosyl. From the perspective of the performance of the catalyst or catalyst component, preferred Group II and Group IIIA metal alkylides are alkylides of magnesium, zinc, and aluminum in which the alkyl group contains 1 to 12 carbon atoms. Specific examples of such compounds include Mg(CH3)2, Mg(C2H5)2, Mg(C2H5)(C4H9), Mg(C4H9)2, Mg(C6H 13 )2, Mg(C 12 H 25 )2, Zn(CH3)2, Zn(C2H5)2, Zn(C4H9)2, Zn(C4H9)(C8H 17 ), Zn(C6H 13 )2, Zn(C6H 13 )3, and AI(C 12 H 25 )3. Alkylides of magnesium, zinc, or aluminum in which each alkyl group contains 1 to 6 carbon atoms can be preferably used.

[0083] Most preferably, alkylaluminum is used as the cocatalyst, and even more preferably, trialkylaluminum in which each alkyl group contains 1 to 6 carbon atoms. In particular, triethylaluminum and triisobutylaluminum or a combination thereof can be used.

[0084] However, if necessary, metal alkylides having one or more halogen or hydride groups, such as ethylaluminum dichloride, diethylaluminum chloride, etc., can be employed.

[0085] A catalyst for the polymerization or copolymerization of α-olefins can be formed by combining the supported titanium-containing catalyst component of the first aspect of the present invention with a cocatalyst component, preferably an alkylaluminum compound.

[0086] Generally, in such a catalyst system, the available molar ratio of aluminum to titanium is from 10:1 to 2000:1, preferably from 50:1 to 1500:1.

[0087] Typically, the catalyst component of the present invention is combined with a cocatalyst and one or more other electron donor compounds for polymerization. In particular, in one embodiment of the present invention, the modifier of structure (1) can be used as both an internal and an external electron donor of the catalyst either alone or in combination with other suitable electron donors.

[0088] However, in a preferred embodiment, the modifier is used as an internal modifier (or internal electron donor), optionally as part of the internal donor mixture as described, and further in combination with one or more other external electron donors.

[0089] The typical molar ratio of aluminum to the external electron donor in such catalyst systems is from 2 to 60.

[0090] A preferred external electron donor is a silane. The typical molar ratio of aluminum to the silane compound in such catalyst systems is from 3 to 50. Preferred silanes include alkyl-, aryl-, and / or alkoxy-substituted silanes containing a hydrocarbon moiety having 1 to 20 carbon atoms. Particularly preferred are silanes having the formula: SiY4, wherein each Y group is the same or different and is an alkyl or alkoxy group containing 1 to 20 carbon atoms. Preferred silanes include isobutyltrimethoxysilane, diisobutyldimethoxysilane, diisopropyldimethoxysilane, n-propyltriethoxysilane, isobutylmethyldimethoxysilane, isobutylisopropyldimethoxysilane, dicyclopentyldimethoxysilane, tetraethyl orthosilicate, dicyclohexyldimethoxysilane, diphenyldimethoxysilane, di-tert-butyldimethoxysilane, and tert-butyltrimethoxysilane.

[0091] Other compounds that can be used as external electron donors (as an alternative or supplement to one or more silanes) are organic compounds containing oxygen, nitrogen, sulfur, and / or phosphorus. Such compounds include organic acids, organic acid anhydrides, organic acid esters, alcohols, ethers, aldehydes, ketones, amines, amine oxides, amides, thiols, various phosphoric acid esters and amides, etc. Mixtures of external electron donors can be used.

[0092] Specific organic acids and esters are benzoic acid, halogenated benzoic acids, phthalic acid, isophthalic acid, terephthalic acid, and their alkyl esters, wherein the alkyl group contains 1 to 6 carbon atoms, such as methyl chlorobenzoate, butyl benzoate, isobutyl benzoate, methyl anisate, ethyl anisate, methyl p-toluate, hexyl benzoate, cyclohexyl benzoate, and diisobutyl phthalate, because these organic acids and esters have good effects in terms of activity and stereospecificity and are convenient to use.

[0093] The catalyst or catalyst component of the present invention can be used in the stereospecific polymerization or copolymerization of α-olefins having 3 or more carbon atoms, such as propylene, 1-butene, 1-pentene, 4-methyl-1-pentene and 1-hexene, and mixtures thereof and mixtures thereof with ethylene.

[0094] Accordingly, in a third aspect, the present invention provides a process for polymerizing propylene or a mixture of propylene with ethylene or C4-C5 α-olefins, the process comprising using the catalyst according to the second aspect.

[0095] The catalyst or catalyst component of the present invention is particularly effective in the stereospecific polymerization or copolymerization of propylene or a mixture thereof with up to 30 mol% of ethylene or a higher carbon α-olefin. By contacting at least one α-olefin with the catalyst or catalyst component under polymerization or copolymerization conditions, highly crystalline poly-α-olefin homopolymers or copolymers can be prepared. Such conditions include the polymerization or copolymerization temperature and time, the pressure of the monomer, the avoidance of catalyst contamination, the choice of the polymerization or copolymerization medium in the slurry process, the use of additives to control the molecular weight of the homopolymer or copolymer, and other conditions well known to those skilled in the art. Slurry-, bulk- and gas-phase polymerization or copolymerization processes are contemplated herein.

[0096] The amount of the catalyst or catalyst component to be used varies with the choice of the polymerization or copolymerization technique, the reactor size, the monomer to be polymerized or copolymerized, and other factors known to those skilled in the art, and can be determined based on the examples set forth hereinafter. Generally, the catalyst or catalyst component of the present invention is used in an amount in the range of 0.2 to 0.02 mg of catalyst per gram of polymer or copolymer produced.

[0097] Regardless of the polymerization or copolymerization process employed, the polymerization or copolymerization should be carried out at a temperature high enough to ensure a reasonable polymerization or copolymerization rate and to avoid unduly long reactor residence times, but the temperature should not be so high as to result in an unreasonably high level of stereoirregular products due to an overly rapid polymerization or copolymerization rate. Generally, the temperature range is from 0 °C to 120 °C, and from the viewpoint of obtaining good catalyst performance and high productivity, a range of 20 °C to 95 °C is preferred. More preferably, the polymerization is carried out at a temperature in the range of 50 °C to 80 °C.

[0098] Olefin polymerization or copolymerization can be carried out at a monomer pressure of atmospheric pressure or above. Generally, the monomer pressure is in the range of 140 to 4100 kPa, but in gas-phase polymerization or copolymerization, the monomer pressure should not be lower than the vapor pressure of the α-olefin to be polymerized or copolymerized at the polymerization or copolymerization temperature.

[0099] In the batch process, the polymerization or copolymerization time will typically be in the range of 1 / 2 to several hours, with a corresponding average residence time in the continuous process. In autoclave type reactions, polymerization or copolymerization times in the range of 1 to 4 hours are typical. In the slurry process, the polymerization or copolymerization time can be adjusted as desired. In the continuous slurry process, polymerization or copolymerization times in the range of 1 / 2 to several hours are usually sufficient.

[0100] Diluents suitable for use in the slurry polymerization or copolymerization process include alkanes and cycloalkanes such as pentane, hexane, heptane, n-octane, isooctane, cyclohexane and methylcyclohexane; alkyl aromatic compounds such as toluene, xylene, ethylbenzene, cumene, ethyltoluene, n-propylbenzene, diethylbenzene and monoalkylnaphthalenes and dialkylnaphthalenes; halogenated and hydrogenated aromatic compounds such as chlorobenzene, chloronaphthalene, o-dichlorobenzene, tetralin, decalin; high molecular weight liquid paraffins or mixtures thereof, and other well-known diluents. It is generally desirable to purify the polymerization or copolymerization medium prior to use, such as by distillation, by percolation through molecular sieves, by contact with compounds capable of removing trace impurities such as alkylaluminum compounds, or by other suitable means.

[0101] Examples of gas phase polymerization or copolymerization processes in which the catalysts or catalyst components of the present invention can be used include both stirred bed reactors and fluidized bed reactor systems, and are described in US 3957448, US 3965083, US 3971786, US 3970611, US 4129701, US 4101289, US 3652527 and US 4003712. Typical gas phase olefin polymerization or copolymerization reactor systems include at least one reactor vessel into which olefin monomers and catalyst components can be added and which contains a stirred bed forming polymer particles. Generally, the catalyst components are added together or separately through one or more valve-controlled ports in the single or first reactor vessel. The olefin monomers are typically supplied to the reactor through a recycle gas system, where unreacted monomers removed as off-gas are mixed with freshly fed monomers and injected into the reactor vessel. To produce impact copolymers, the homopolymer formed from the first monomer in the first reactor is reacted with the second monomer in the second reactor. A quench liquid (which can be a liquid monomer) can be added to the polymerizing or copolymerizing olefins through the recycle gas system to control the temperature.

[0102] Regardless of the polymerization or copolymerization technique, polymerization or copolymerization is typically carried out under conditions that exclude water and other materials that act as catalyst poisons. Additionally, polymerization or copolymerization can be carried out in the presence of additives to control the molecular weight of the polymer or copolymer. Hydrogen gas is typically employed in a manner well known to those skilled in the art for this purpose. Although not typically required, after polymerization or copolymerization is complete, or when it is desired to terminate the polymerization or copolymerization or at least temporarily deactivate the catalyst or catalyst component of the present invention, the catalyst can be contacted with water, an alcohol, acetone, or other suitable catalyst deactivator in a manner known to those skilled in the art.

[0103] The resulting product is typically a solid, mainly isotactic poly-α-olefins. The yield of the homopolymer or copolymer is high enough relative to the amount of catalyst employed such that a useful product can be obtained without separating the catalyst residue. Additionally, the level of atactic by-products is low enough such that a useful product can be obtained without separating them. The polymer or copolymer product produced in the presence of the catalyst or catalyst component can be fabricated into useful articles by extrusion, injection molding, and other common techniques.

[0104] The polymer product mainly contains highly crystalline propylene polymers. Propylene polymers having a high degree of polypropylene crystallinity are now well known in the art. It has long been recognized that crystalline propylene polymers (described as "isotactic" polypropylene) contain crystalline domains interspersed with some non-crystalline domains. The non-crystalline domains may be due to defects in the regular isotactic polymer chains that hinder the formation of perfect polymer crystals. The degree of stereoregularity of the polypropylene in the polymer can be measured by well-known techniques such as the isotactic index, the crystallization melting temperature, the flexural modulus, and more recently by determining the relative percentage of meso pentads (%m4) by carbon-13 nuclear magnetic resonance ( 13 C NMR).

[0105] The invention described herein will be illustrated by the following examples, but is not limited thereto.

[0106] Example 1

[0107] As described below, a supported catalyst component according to the present invention was prepared and tested for propylene polymerization.

[0108] Each example used a magnesium alkoxide support prepared according to the examples of WO 2005044873A1.

[0109] To a slurry of 0.15 g of the Mg alkoxide support was added 2 ml of toluene and 0.1 mmol of the corresponding modifier. The resulting slurry was stirred at 100 °C for 10 minutes. The mixture was then allowed to settle for 30 minutes, and the liquid phase was decanted off with a pipette.

[0110] The remaining solid was then mixed with 1 ml of toluene and 1 ml of TiCl4 and then heated to 100 °C. Then, a modifier (0.1 mmol) was added at 100 °C (see Table 1) and the reaction mixture was stirred at the above temperature for 1 hour. The slurry was allowed to settle and cooled to room temperature and kept for 30 minutes. The liquid was decanted with a pipette.

[0111] The solid residue was mixed with 1 ml of toluene and 1 ml of TiCl4 and the reaction mixture was stirred at 120 °C for 30 minutes. The resulting suspension was cooled to room temperature and allowed to settle for 30 minutes. The liquid was decanted and the resulting catalyst was washed with heptane (4 x 2.5 ml, 10 min). The catalyst was then dried under reduced pressure.

[0112] Examples 2-9

[0113] The procedure of Example 1 was repeated, except that the modifier shown in Table 1 was used.

[0114] Propylene polymerization.

[0115] A batch slurry-phase propylene polymerization reaction was carried out in a 2-liter autoclave reactor at 71 °C with a total reactor pressure of 1.0 MPa, while stirring at 500 revolutions per minute and the reaction time was 2 hours.

[0116] Triethylaluminum (TEA) was used as a cocatalyst and diisobutyl dimethoxysilane was used as an external donor together. TEA / donor, catalyst component, hydrogen, and propylene were charged into the reactor in sequence.

[0117] In a typical procedure, a catalyst (-20 mg), triethylaluminum (3.6 mL of a 0.75 M heptane solution), diisobutyl dimethoxysilane (1.0 mL of a 0.15 M heptane solution), and 850 mL of heptane were charged into a dry, nitrogen-purged 2-liter stainless-steel autoclave reactor at 40 °C. 7 millimoles of hydrogen were introduced at about 85 kPa. Stirring and heating were started and a 100 kPa pressure drop was introduced into the reactor from a 75 mL container filled with hydrogen, followed by the introduction of about 30 grams of a propylene portion. When the temperature reached 71 °C, the propylene storage tank towards the reactor was opened and a constant propylene pressure of 1.0 MPa psig was maintained for one hour. Then the reactor was vented and the resulting polymer slurry was poured out of the reactor, filtered, and dried.

[0118] The results are shown in Table 1:

[0119] Table 1

[0120]

[0121]

[0122] The results showed that the catalyst according to the present invention produced polypropylene in good yields.

Claims

1. A hydrocarbon-insoluble solid catalyst component, said component containing magnesium, titanium and a halogen and further comprising a modifier compound having structure (1): wherein R 1 selected from H, aryl or an alkyl group having 1 to 10 carbon atoms, R 2 selected from alkyl groups having 1 to 10 carbon atoms, R 3 to R 6 each independently selected from H, alkylaryl, aryl or an alkyl group having 1 to 10 carbon atoms, and halogen, provided that at least one of R 4 and R 5 is H, Any alkylaryl, aryl or alkyl group optionally contains one or more heteroatoms and / or optionally wherein R 3 and R 4 or R 5 and R 6 are linked to form a cyclic group.

2. The catalyst component according to claim 1, wherein R 1 is hydrogen or methyl.

3. The catalyst component according to claim 1 or claim 2, wherein R 2 is an alkyl group selected from methyl, ethyl, propyl and butyl.

4. The catalyst component according to any one of the preceding claims, wherein R 3 to R 6 are each hydrogen.

5. The catalyst component according to claim 4, wherein R 1 is hydrogen and R 2 is an alkyl group selected from methyl, ethyl, and butyl.

6. The catalyst component according to any one of claims 1 to 3, wherein at least one of R 3 to R 6 is a halogen.

7. The catalyst component according to claim 6, wherein R 1 is hydrogen, R 2 is methyl, R 3 , R 4 and R 6 are hydrogen, and R 5 is bromine.

8. The catalyst component according to any one of claims 1 to 3 and 6, wherein at least one of R 3 to R 6 is an alkyl group having 1 to 6 carbon atoms.

9. The catalyst component according to claim 8, wherein R 1 is hydrogen, R 2 is methyl, R 3 and R 5 are tert-butyl, and R 4 and R 6 are hydrogen.

10. The catalyst component according to claim 8, wherein R 1 is hydrogen, R 2 is butyl, R 3 to R 5 are hydrogen, and R 6 is methyl.

11. The catalyst component according to claim 1, wherein the modifier has the following structure: wherein R 5 is H, and R 7 to R 10 each independently selected from H, alkylaryl, aryl or an alkyl group having 1 to 6 carbon atoms, and halogen, and the alkylaryl, aryl and alkyl groups optionally contain one or more heteroatoms.

12. The catalyst component according to claim 11, wherein R 2 is ethyl, and R 1 and R 5 to R 10 are all hydrogen.

13. The catalyst component according to any one of the preceding claims, wherein the modifier compound having structure (1) is an internal modifier.

14. A catalyst useful for polymerizing olefins, said catalyst comprising: i) a hydrocarbon-insoluble solid catalyst component according to any one of claims 1 to 13, and ii) at least one cocatalyst component.

15. A process for polymerizing propylene or a mixture of propylene with ethylene or a C4-C5 α-olefin, said process comprising using the catalyst according to claim 14.

Images