WO1998046650A1

WO1998046650A1 - Catalyst preparations for producing olefin (co)polymers

Info

Publication number: WO1998046650A1
Application number: PCT/EP1998/001787
Authority: WO
Inventors: Michael GEPRÄGS; Walter Heitz; Uwe Peucker
Original assignee: Basf Aktiengesellschaft
Priority date: 1997-04-11
Filing date: 1998-03-26
Publication date: 1998-10-22
Also published as: AU7042098A; DE19715155A1; JP2001518968A; EP0973810A1

Abstract

The invention relates to a catalyst preparation which can be obtained by mixing a metal complex (A) wherein the substituents have the following meaning: M means chromium, molybdenum or wolframium; Z means fluorine, chlorine, bromine, iodine, hydrogen or C1 - C20 alkyl; R1 to R5 independently mean hydrogen, C¿1? - C10 alkyl, C3 to C7 cycloalkyl unsubstituted or substituted by C1 - C10 alkyl, C6 - C18 aryl, and substituted C6 - C18 aryl and 2 adjacent radicals can jointly mean saturated or unsaturated cyclic groups with 4 to 18 C atoms, or Si(R?6)¿3 with R6 meaning independently C1 - C10 alkyl, C3 to C10 cycloalkyl or C6 - C18 aryl, Y means independently C1 - C20 alkyl, C3 to C10 cycloalkyl, C6 - C18 aryl or aralkyl with 1 to 10 C atoms in the alkyl radical and 6 to 18 C atoms in the aryl radical; and a metallocene-ion forming compound (B) in an inert liquid reaction medium.

Description

Catalyst preparations for the production of olefin (co) polymers

description

The present invention relates to a catalyst preparation suitable for the (co) polymerisation of olefins, obtainable by mixing a metal complex of the general formula (A)

in which the substituents have the following meaning:

M independently of one another chromium, molybdenum or tungsten,

Z independently of one another fluorine, chlorine, bromine, iodine, hydrogen or Ci to C ₂₀ alkyl,

R ¹ to R ⁵ independently of one another are hydrogen, Ci- to Cio-alkyl, unsubstituted or substituted by Ci- to Cio-alkyl C- ₃ - to C ₇ -cycloalkyl, C ₆ - to cis-aryl, substituted C ₆ - to Ciβ Aryl, where 2 adjacent radicals can together represent 4 to 18 carbon atoms having saturated or unsaturated cyclic groups, or Si (R ⁶ ) ₃ with

R6 independently of one another Ci - to Cio-alkyl, C ₃ - to Cio - cycloalkyl or C ₆ - Cis-aryl,

independently of one another Ci to C ₀ alkyl, C ₃ to Cio-cycloalkyl, C ₆ to Cis aryl or aralkyl having 1 to 10 C atoms in the alkyl radical and 6 to 18 C atoms in the aryl radical, and a compound (B) forming metallocenium ions in an inert liquid reaction medium.

The present invention further relates to the use of the catalyst preparation mentioned for the (co) polymerization of olefins and to a process for the preparation of olefin (co) polymers from cycloolefinic and / or α-olefinic monomer units.

Heterogeneous catalyst systems based on chromium as transition metal which are suitable for the polymerization of olefins have been known for some time (see also A. Clark, Catal. Rev. 1969, 3, 145 and FJ Karol, GL Brown, JM Davison, J. Polym. , Polym. Chem. Ed. 1973, 11, 413). Homogeneous chromium (III) catalysts such as [Cp * Cr (OMe ₂ ) ₂ CH ₂ SiMe ₃ ] ⁺ B (Ph) ₄ ^" (Cp * = pentamethylcyclopentadienyl; Me = methyl) are according to Theopold et al. (Organometallics 1996, 15, 5473 - 5475) is particularly suitable for the polymerization of ethene, but only oligomer mixtures are obtained from propene or 1-hexene, and the polymerization is successful with the complex Cp * (py) Cr (Me) (Ot-Bu) (py = pyridine) of norbornene in good yields by the mechanism of ring-opening metathesis polymerization, but the polymers have a broad molecular weight distribution.

Binuclear chromium complexes such as [Cp * Cr (CH ₃ ) (μ-Cl)] ₂ or

[Cp * (CH ₃ ) Cr (μ-CH ₃ )] ₂ , on the other hand, have only a very low catalytic activity even for ethylene (cf. Theopold et al., "Homogeneous Chromium Catalysts for Olefin Polymerization" in "Advances in Chemistry "Series 230, Eds. WR Moser, DW Slo-cum, 1992, 591-602).

1,2-linked norbornene is characterized by high temperature and chemical resistance. However, this is eg by means of palladium catalysis according to Risse et al. (J. Mol. Catal. 1992, 76, 219) or Sen et al. (J. Organomet. Chem. 1988, 358, 567) available homopolynorbornene is usually amorphous and has a very high glass transition temperature (T _g value) at which decomposition already occurs, which precludes practical further processing from the outset. By installing comonomers in the polynorbornene framework, its T _g value can be reduced. However, the copolymerization catalysts based on zirconium or titanium complexes (see also Makromol. Chem., Macromol. Symp. 1991, 47, 83 and EP-A 0 283 164) which are suitable for this purpose can only be obtained in a preparatively complex manner, very much sensitive and can also open the ring of the cycloolefin Component lead to polymers with double bond units, which entails the risk of crosslinking during processing and thus a deterioration in the mechanical properties. Homoleptic chromium (III) allyl complexes also polymerize cycloolefins with ring opening and lead to unsaturated polymers with the disadvantages already described (cf. VA Kormer et al., J. Polym. Sei. Part. Al, 1992, 10, 251-258).

There is therefore still a lack of homogeneous catalyst preparations based on metals from group VIB of the Periodic Table of the Elements, which are suitable both for the homo- and for the copolymerization of cycloolefinic and / or α-olefinic monomer units, and at the same time on preparatively simple ones Can be obtained, selectively polymerize cycloolefins while maintaining the ring and ensure a high degree of comonomer incorporation.

The present invention was therefore based on the object of providing catalyst systems based on metals from group VIB of the periodic table of the elements which are suitable for the homo- and copolymerization of cycloolefinic and / or α-olefinic monomer units. The invention was also based on the object of finding a process for the preparation of (co) polymers from cycloolefinic and / or α-olefinic monomer units.

Accordingly, the catalyst preparation described at the outset and its use for the (co) polymerization of cycloolefinic and / or α-olefinic monomer units have been found. Furthermore, a method for the production of

Olefin (co) poly eres from cycloolefinic and / or α-olefinic monomer units found.

Preference is given to those catalyst preparations which can be obtained by mixing a metal complex (A)

in which the substituents have the following meaning:

M chrome,

Z independently of one another chlorine, bromine, iodine, hydrogen or C ₁ -C ₆ -alkyl,

R ¹ to R ⁵ independently of one another hydrogen, Ci to C ₆ alkyl, unsubstituted or substituted by Ci to C ₆ alkyl substituted C ₅ to C cycloalkyl, C ₆ to C ₅ aryl, substituted C ₆ to Cis-aryl, where 2 adjacent radicals together can represent saturated or unsaturated cyclic groups having 4 to 15 carbon atoms, or Si (R ⁶ ) ₃ with

R ⁶ independently of one another are C 1 to C ₆ alkyl, C ₃ to C ₆ cycloalkyl or C ₆ to Cio aryl, and

independently of one another C ₁ to C 10 alkyl, C ₃ to C ₆ cycloalkyl, C ₆ to C ₅ aryl or aralkyl having 1 to 6 C atoms in the alkyl radical and 6 to 15 C atoms in the aryl radical,

and a metallocenium ion-forming compound (B) which, for example, is an open-chain and / or cyclic alumoxane compound of the general formula (BI) or (B-II)

R ⁷

wherein

R ⁷ independently of one another denotes a C 1 -C 4 -alkyl group and

m represents an integer from 5 to 30,

represents in an inert liquid reaction medium.

Suitable metals M in complexes (A) are the metals from group VIB of the Periodic Table of the Elements, that is, in addition to molybdenum and tungsten, especially chromium. Those binuclear complexes (A) which exclusively have chromium as metal M are preferred. The metals mentioned are generally present in the metal complexes (A) with a triple positive charge.

The bridging igand Z of the binuclear complex (A) is, in particular, independently of one another, in particular fluorine, chlorine, bromine, iodine, hydrogen or C 1 -C ₂₀ -alkyl, preferably C ₁ -C ₆ -alkyl, such as methyl, ethyl, n-propyl, n-butyl or n-hexyl, in question. Chlorine, bromine, iodine and C 1 -C 6 -alkyl, such as methyl or n-butyl, are particularly suitable, chlorine, iodine or bromine being preferably used. Z is usually present in (A) as a μ-ligand. The two bridge ligands Z can be the same or different, but in general these ligands are identical.

In addition to cyclopentadienyl (R ¹ to R ⁵ = H), the negatively charged 5-membered carbocycles which can be mono- or polysubstituted, for example linear, with halogen, such as fluorine, chlorine or bromine, are suitable as the monoanionic cyclic ligand or branched Ci- to Cio-alkyl, preferably Ci to _C6 alkyl such as methyl, ethyl, n-propyl, i-propyl, n-butyl or t-butyl, C ₃ - to C cycloalkyl, preferably C ₅ - to C ₇ -cycloalkyl, such as cyclopropyl or cyclohexyl, or C ₆ - to cis-aryl, preferably C ₆ - to cis-aryl, such as phenyl or naphthyl. Among aryl substituents also fall, for example, with Ci to _C6 alkyl such as methyl or 1-propyl, or with halogen, such as fluorine, chlorine or bromine-substituted C ₆ - to C-aryl, preferably C ₆ to -aryl. Two adjacent radicals, for example R ¹ and R ² or R ³ and R ⁴ , can also together form a saturated or unsaturated cyclic group containing 4 to 18, preferably 4 to 15 carbon atoms. This also includes fused-on unsaturated or aromatic rings or ortho-fused aryl units, which gives, for example, indenyl, fluorenyl or benzindenyl systems.

Also suitable as radicals R ¹ to R ^{5 are} silyl substituents Si (R ⁶ ) ₃ , in which the radicals R ⁶ , independently of one another, C 1 to C 10 alkyl, preferably C 1 to C ₆ alkyl, for example methyl, ethyl or i-Propyl, C ₃ - to Cio-cycloalkyl, preferably C ₃ - to C ₆ -cycloalkyl, for example cyclopropyl or cyclohexyl, or C ₆ - to cis-aryl, preferably C ₆ - to Cio-aryl, for example phenyl.

As the metal M complexing ligands are particularly suitable among the aforementioned compounds cyclopentadienyl, penta-Ci to Cβ-alkylcyclopentadienyl, indenyl, fluorenyl or benz - indenyl, the last three ligands mentioned one or more times with Ci to C ₆ - Alkyl groups can be substituted. Cyclopentadienyl, Penta-Ci- are preferred to C ₄ -alkylcyclopenta- dienyl, indenyl, and 1- to 3 -fold Ci- to C-alkylated indenyl. Cyclopentadienyl or pentamethylcyclopentadienyl are particularly preferred. Binuclear complexes (A) are usually used which have two identical complexing cyclic monoanionic ligands. However, these ligands can also differ from one another in their ring system and / or substitution pattern.

The formally monovalent ligand Y preferably represents linear or branched C ₁ -C 20 -alkyl, in particular C ₁ -C 10 -alkyl, for example methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t- Butyl, C ₃ - to Cio-cycloalkyl, preferably C ₃ - to C ₆ -cycloalkyl, such as cyclopropyl or cyclohexyl, C ₆ - to cis-aryl, preferably C ₆ - to cis-aryl, such as phenyl or naphthyl, or aralkyl 1 to 10, in particular with 1 to 6 carbon atoms in the alkyl radical and 6 to 18, in particular 6 to 15 carbon atoms in the aryl radical, for example benzyl. Particularly suitable as ligand Y are n-propyl, i-propyl or naphthyl and in particular methyl, ethyl, n-butyl, i-butyl, t-butyl, phenyl or benzyl. The radicals Y can be either the same or different, but are preferably present as identical ligands. Particularly preferred metal complexes (A) are bis [μ-chloro (methyl) penta ethylcyclopentadienyl chromium (III)], bis [μ-bromo (methyl) pentamethylcyclopentadienyl chromium (III)], bis [μ-chlorocyclopentadienyl (methyl) chromium (III)], Bis tμ-chloro (ethyl) pentamethylcyclopentadienylchrom (III)], bis tμ-chloro (phenyl) pentamethylcyclopentadienylchrom (III)], bis [μ-chloro (benzyl) pentamethylcyclopentadienylchrom (III)], bis [μ-chloropentamethylcyclopentilienyl (trim) chromium (III)] and bis [μ-chlorocyclopentadienyl (trimethylsilylmethyl) chromium (III)]. Very particularly preferred metal catalysts A) are bis [μ-chloro (methyl) pentamethylcyclopentadienyl chromium (III)], bis [μ-chloro (ethyl) pentamethylcyclopentadienyl chromium (III)], bis [μ-chloro (phenyl) pentamethylcyclopentadienyl chromium (III)] and bis [μ-chloro (benzyl) pentamethylcyclopentadienyl chromium (III)].

The catalyst preparation according to the invention can contain only a defined metal complex of the formula (A) and can also comprise any mixture of compounds covered by the general formula (A).

For the preparation of the metal complexes of the general formula (A), methods known from the literature, as in Richeson et al. (Organometallics 1989, 8, 2570 - 2577). The cyclopentadienyl ligand is generally introduced by treating complex salts, such as tris (tetrahydrofuran) chromium (III) chloride, with organometallic compounds, such as pentamethylcyclopentadienyllithium. The complex obtained is then alkylated with Grignard organic compounds, such as benzyl magnesium chloride or lithium organic compounds, such as methyl lithium, to form a binuclear complex. The reactions described are usually carried out at temperatures between -50 ° C and + 70 ° C.

As a further component, the catalyst preparation according to the invention contains a compound (B) which forms metallocenium ions. In addition to the alumoxane compounds mentioned, suitable compounds which form metallocenium ions are strong, neutral Lewis acids and ionic compounds with Lewis acid cations.

As ionic compounds are compounds with Lewis acid cations of the general formula (B-III)

G ¹⁺ (TX ¹ XX ³ X ⁴ ) ₁ ^" (B-III) suitable in the

G represents an element of main group I or II of the Periodic Table of the Elements, such as lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium or barium, in particular lithium or sodium,

T an element of III. Main group of the periodic table of the elements means, in particular boron, aluminum or galium, preferably boron,

X ¹ to X ⁴ independently of one another for hydrogen, linear or branched Ci to Co alkyl, preferably Ci to Ci alkyl, such as methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t -Butyl or n-hexyl, mono- or polysubstituted Ci to C ₂ o alkyl, preferably Ci to Cio alkyl, for example with halogen atoms such as fluorine, chlorine, bromine or iodine, C ₆ to Cis aryl, preferably C ₆ - to Cis-aryl, for example phenyl, which can also be substituted one or more times, for example with halogen atoms such as fluorine, chlorine, bromine or iodine, for example pentafluorophenyl, aralkyl with 1 to 10 C atoms, preferably 1 to 6 carbon atoms in the alkyl radical and 6 to 18 carbon atoms, preferably 6 to 15 carbon atoms in the aryl radical, for example benzyl, fluorine, chlorine, bromine, iodine, Ci to C ₂ o-alkoxy, preferably Ci to

C o-alkoxy, such as methoxy, ethoxy or i-propoxy, or C ₆ - to cis-aryloxy, preferably C ₆ - to cis-aryloxy, for example phenoxy, and

1 means 1 or 2.

The anion in a compound of the general formula (B-III) is preferably a non-coordinating counterion. Boron compounds as mentioned in WO 91/09882, to which express reference is made here; tetrakis (pentafluorophenyl) borate is preferred.

Compounds of the general formula (B-IV) are strong, neutral Lewis acids

TX ⁵ X ⁶ X ⁷ (B-IV)

preferred in the T an element of III. Main group of the periodic table of the elements means, in particular boron, aluminum or galium, preferably boron,

X ⁵ to X ⁷ independently of one another for hydrogen, linear or branched Ci to Co alkyl, preferably Ci to C ₀ alkyl, such as methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t-butyl or n-hexyl, mono- or polysubstituted ci- to co-alkyl, preferably ci- to cio-alkyl, for example with halogen atoms such as fluorine, chlorine,

Bromine or iodine, C ₆ - to cis-aryl, preferably C ₆ - to cis-aryl, for example phenyl, which can also be substituted one or more times, for example with halogen atoms such as fluorine, chlorine, bromine or iodine, for example pentafluorophenyl, aralkyl with 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms in the alkyl radical and 6 to 18 carbon atoms, preferably 6 to 15 carbon atoms in the aryl radical, for example benzyl or fluorine, chlorine, bromine or iodine.

Particularly preferred among the radicals X ⁵ to X ⁷ are those which have halogen substituents. Pentafluorophenyl should preferably be mentioned. Particularly preferred are compounds of the general formula (B-IV) in which X ⁵ , X ⁶ and X ^{7 are the} same, preferably tris (pentafluorophenyl) bora.

In principle, those compounds which have an Al — C bond are suitable as alumoxane compounds.

Open-chain or cyclic alumoxane compounds of the general formula (B-I) or (B-II), in which, are particularly suitable as compounds (B) forming metallocenium ions

R ⁷ independently of one another denotes a C 1 -C 4 -alkyl group, preferably a methyl or ethyl group, and m represents an integer from 5 to 30, preferably 10 to 25.

These oligomeric alumoxane compounds are usually prepared by reacting a solution of trialkylaluminum with water and include in EP-A 0 284 708 and US-A 4,794,096.

As a rule, the oligomeric alumoxane compounds obtained are mixtures of both linear and cyclic chain molecules of different lengths, so that m is to be regarded as the mean. The alumoxane compounds can also be present in a mixture with other metal alkyls, preferably with aluminum alkyls, such as triisobutyl aluminum or triethyl aluminum. Prefers methylalumoxane is used, the production of which is described in detail, for example, in EP-A 284 708.

Furthermore, as metallocenium ion-forming compounds (B) aryloxyalumoxanes, as described in US Pat. No. 5,391,793, amidoaluminoxanes, as described in US Pat , as described in EP-A 0 621 279, or mixtures thereof are used.

The alumoxanes described are used either as such or in the form of a solution or suspension, for example in aliphatic or aromatic hydrocarbons, such as toluene or xylene, or mixtures thereof.

In the event that Z in general formula (A) is halogen, i.e. Fluorine, chlorine, bromine or iodine and especially chlorine, bromine or iodine means, in a particularly preferred embodiment of the catalyst preparation according to the invention, the listed alumoxane compounds (B-I) and / or (B-II) are used as component (B). Alternatively or in a mixture with the alumoxanes, ionic compounds with Lewis acid cations of the general formula (B-IV) can also be used. If, on the other hand, the ligand Z in (A) represents hydrogen or a Ci to Co alkyl radical, the above-mentioned strong, neutral Lewis acids (B-III) preferred.

Components (A) and (B) of the catalyst preparation according to the invention can be mixed together in an inert liquid reaction medium. For the purposes of the present invention, a reaction medium is considered inert if it is essentially free of water, compounds containing hydroxyl groups and oxygen. Suitable inert liquid reaction media are those in which components (A) and (B) are partially or completely soluble. Preferred are liquids which are at least slightly polar, for example aromatic hydrocarbons with 6 to 20 carbon atoms, such as benzene, toluene or xylene. Toluene and xylene and mixtures thereof are particularly preferred. As a rule, aliphatic hydrocarbons or halogenated aliphatic hydrocarbons can also be used, such as pentane, hexane, octane, perfluoromethylcyclohexane, perfluorohexane, perfluorooctane, perfluorodecalin or mixtures thereof. It is also possible to use mixtures consisting of aromatic and / or aliphatic hydrocarbons. The preferred inert reaction medium is toluene. Components (A) and (B) can be added to the reaction medium at the same time or in succession, the sequence of addition generally not being important. The metal complex (A) is usually initially introduced and then component (B) is added with stirring. In general, components (A) and (B) are allowed to act in the reaction medium for a period in the range from 0.1 sec to 60 min, preferably from 0.1 sec to 30 min, before the catalyst preparation with the starting mixture to be polymerized Is brought into contact. The process steps described are advantageously carried out under a protective gas atmosphere in order to avoid contamination with moisture or oxygen. The catalyst preparation according to the invention is generally produced at temperatures in the range from -50 to 50 ° C., preferably in the range from -10 to 40 ° C.

Catalyst preparations in which the molar ratio of the amount of alumoxane compound (B) to the amount of component (A) used are in the range from 10: 1 to 10 ⁶ : 1 and in particular in the range from 10: 1 to 10: 1 are particularly suitable .

If the metallocenium ion-forming compound (B) is based on a component containing boron, it has proven particularly suitable if the molar ratio of boron from the metallocenium ion-forming compound (B) to transition metal from the metal complex (A) is in the range from 0.1 : 1 to 10: 1, in particular from 1: 1 to 5: 1.

The catalyst preparations according to the invention can be used for the production of olefin (co) polymers.

According to a suitable process for the production of olefin (co) polymers, cycloolefinic and / or α-olefinic monomer units are produced at a temperature in the range from -50 to 150 ° C., preferably in the range from -15 to 60 ° C. and particularly preferably in the range polymerized from -5 to 40 ° C in the presence of the inventive catalyst systems described above.

In principle, all monomers of these classes of compounds come as cyclo- or α-olefinic monomer units, e.g. bridged or non-bridged cycloolefins and mono- or diolefins.

Among the cycloolefinic monomer units, strained ring systems are advantageously used which have one or more olefinic bonds in the cycle. Tensioned ring systems are to be understood in particular as those at which the bond geometry of the double bond units shows deviations from corresponding free, untensioned systems. The deviations can either be that the bond angles in the sp ² plane do not allow an optimal overlap of the orbitals involved, or that a bond from the sp ² plane is forced. For example, cyclopropene, cyclopentene, dicyclopentadiene, bicyclo [2.2.1] hept-2-ene or bicyclo [2.2.2] oct-2-ene come as cycloolefinic monomer units, in each case also in substituted form, for example with alkyl, aryl or functional groups based on elements from groups IVA, VA, VIA or VIIA of the Periodic Table of the Elements.

Particularly preferred among the cycloolefinic monomers are norbornene (= bicyclo [2.2.1] hept-2-ene] and derivatives of norbornene. For the purposes of the present invention, norbornene derivatives are, for example, compounds in which the carbon valences that are not at the Ring formation are involved, by alkyl radicals, such as methyl, ethyl, i-, n-propyl, i-, n-, s-, t-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl or their structure analogues Cycloalkyl radicals, such as cyclopropyl, cyclopentyl, cyclohexyl, are substituted by aryl radicals, such as phenyl or naphthyl, or by alkylaryl radicals, such as benzyl Periodic table of the elements, such as silyl, carboxy, ester, amide, amino-hydroxy, alkoxy or phosphate groups.

Both single and multiple substituted norbornene derivatives can be used.

The α-olefinic compounds used in the process according to the invention are, for example, ethylene or C ₃ -C ₁ -alkenes, in particular C ₃ -C 1 -alk-1-enes. Ethylene, propylene, but-1-ene, isobutene, 4-methyl-pent-1-ene, hex-1-ene, oct-1-ene and mixtures thereof are preferred, and ethylene is particularly preferred.

In principle, mixtures of cycloolefinic or α-olefinic monomers or mixtures of cycloolefinic and α-olefinic monomers can also be used.

In a preferred embodiment, the cyclo- and / or α-olefinic monomer units are polymerized in the presence of a catalyst system which comprises a metal complex (A) in which the substituents have the following meaning:

M chrome,

Z independently of one another chlorine, bromine, iodine, hydrogen or C - to C ₆ -alkyl,

R ¹ to R ⁵ independently of one another are hydrogen, Ci to C ₆ alkyl, unsubstituted or substituted by C ₁ to C 10 alkyl, C ₃ to C ₇ cycloalkyl, C ₆ to Cis aryl, substituted Cζ to Cis Aryl, where 2 adjacent radicals together can represent saturated or unsaturated cyclic groups having 4 to 15 carbon atoms, or Si (R ⁶ ) ₃ with

Y Ci to Cio alkyl, C ₃ to C ₆ cycloalkyl, C ₆ to Cis aryl or aralkyl with 1 to 10 C atoms in the alkyl radical and 6 to 15 C atoms in the aryl radical,

and open-chain and / or cyclic alumoxane compounds of the formulas (B-I) and (B-II)

R ⁷

wherein

R ⁷ independently of one another denotes a C 1 -C 4 -alkyl group and

m represents an integer from 5 to 30,

contains. With regard to preferred embodiments for the catalyst components (A) and (B), the statements made above apply accordingly. Accordingly, for example, alumoxane compounds or ionic compounds with Lewis acid cations as component (B) are preferred when Z in (A) is halogen. Strong, neutral Lewis acids, on the other hand, are preferred when Z in (A) is Ci to C o-alkyl or hydrogen.

The process according to the invention comprises both bulk polymerization, i.e. in a monomer which is already in liquid form at atmospheric pressure or which liquefies only under the selected reaction pressures, such as ethylene, propylene, norbornene, tetracyclododecene, cyclopentene or cyclooctene, and also the polymerization in solution. In the case of polymerization in solution, aliphatic or aromatic hydrocarbons having 4 to 20 carbon atoms or mixtures thereof, for example butane, pentane, hexane, cyclohexane, toluene, xylene or ethylbenzene, can be used as suitable solvents.

The polymerization is preferably carried out at temperatures in the range from -50 to 150 ° C., in particular in the range from -5 to 40 ° C., and at a pressure from 0.1 to 100 bar, particularly preferably from 0.1 to 50 bar and in particular from 0.5 to 20 bar. The usual polymerization times are in the range from 0.5 to 100 hours, but satisfactory polymerization results can also be achieved with reaction times in the range from 0.5 to 10 hours.

The starting monomer concentration is usually set to a value in the range from 0.1 to 8.5 mol / 1.

The components (A) and (B) of the catalyst system can be added to the reaction mixture in different ways. The metal complex (A) is usually initially introduced, then the monomer (s) are added and the compound (B) which forms metallocenium ions is then added either as a solid or in dissolved or suspended form. Alternatively, the monomer can be introduced and then components (A) and (B) of the catalyst system can be added, regardless of the order of addition. In a further embodiment, the catalyst preparation according to the invention described above, ie the mixture of components (A) and (B) prepared beforehand in an inert reaction medium, is used. The catalyst preparation according to the invention can either be added to the starting monomer or, if appropriate, placed in a polymerization medium. The polymerization can be terminated, for example, by adding protic compounds, for example alcohols, such as methanol, dilute mineral acids, such as hydrochloric acid (HC1), or carboxylic acids, such as acetic acid, or mixtures thereof. The volume ratio of termination reagent to reaction mixture is generally in the range from 1: 1 to 1:10. The polymer product is isolated in a customary manner, for example by precipitation in an excess alcohol such as methanol.

With the methods according to the invention, both homopolymers and copolymers can be obtained from the olefinic monomer units described above. The polymers mentioned are also summarized here under the name olefin (co) polymers. The term (co) polymerization also includes the homo- and copolymerization of the olefinic monomer units listed.

Examples of homopolymers which are obtainable from cycloolefinic monomers are polymers of norbornene, cyclopentadiene and cyclopentene.

With the aid of the process according to the invention, olefin (co) polymers can be obtained in high molecular weight. Olefin (co) polymers with average molecular weights M _n up to 2 million g / mol can be produced. Polymers with average molecular weights in the range from 5,000 to 1,000,000, particularly preferably in the range from 10,000 to 500,000 g / mol, are preferably obtained.

The molecular weight distributions M _w / M _n obtained generally range from 1.03 to 3.5 and preferably assume values in the range from 1.05 to 2.0. The molecular weights M _n and the molecular weight distributions M _w / M _n can be determined by gel permeation chromatography (GPC), based on a polystyrene standard.

The copolymers of cycloolefinic and α-olefinic monomer units accessible via the process according to the invention can consist of up to 99% by weight, based on the total copolymer, of a copolymerized component which is based on a cycloolefinic monomer unit. Accordingly, copolymers of at least one cycloolefinic component, such as norbornene, and at least one α-olefinic component, such as ethylene, which contain 5 to 95% by weight and in particular 20 to 70% by weight of a component based on a cycloolefinic monomer unit, are accessible . In general, olefin (co) polymers with cycloolefinic monomer units have a T _g value which is considerably reduced in comparison with homopolymers made from these cycloolefins. For example, the τ _g value of a norbornene / ethene copolymer obtained by the process according to the invention with a molar fraction of 60% of ethene is 40.1 ° C. (determined by means of DSC) (the T _g value of polynorbornene is above 300 ° C). In general, copolymers with a proportion of cycloolefinic monomer units whose glass transition temperature value can be set over a wide range are accessible via the processes according to the invention. For example, copolymers are available with Tg values in the range from 100 ° C. to -60 ° C. and in particular from 60 ° C. to -40 ° C. These copolymers containing cycloolefin units are usually crystalline only from a proportion of 80 mol% of α-olefin component, for example ethylene (determined on the basis of X-ray powder spectra with the aid of a wide-angle goniometer (Cu-K _f radiation, 1.54

On .

With the processes according to the invention, cycloolefinic monomer units are linked by a 1, 2 linkage, i.e. while maintaining the ring system, incorporated into homo- or copolymers.

With the method according to the invention, homo- and copolymers containing cycloolefinic monomer units in high molecular form are accessible. In particular, the invention enables

Catalyst system a high comonomer incorporation of cyclolefinic monomers, as a result of which polymer products which are readily soluble in organic solvents and have an adjustable glass transition temperature are obtained. Furthermore, good results can be achieved even with a low ratio of component (B) to metal complex (A) forming metallocenium ions and with a relatively low polymerization temperature. Another advantage is that the metal complex (A) is easily accessible preparatively. The process according to the invention thus permits a process — technically simple preparation of olefin (co) polymers. By doing

Cycloolefin monomers can be polymerized with ring retention is also avoided that the polymers obtained have (additional) double bond units, which ultimately has an advantageous effect on the mechanical and rheological properties of the polymer molding compositions.

The present invention is illustrated by the following examples. Examples

^X H-NMR measurements were taken on the spectrometers AMX 500 (measuring frequency 500 MHz) or AC 300 (measuring frequency 300 MHz) from Bruker. The δ scale was calibrated using the deuterated solvents used in each case. The molecular weights M _n and the molecular weight distribution D = M _w / M _n were determined by gel permeation chromatography (GPC), based on a polystyrene standard.

The DSC data were determined using the Mettler DSC 30 at a heating rate of 10 K / min.

i) Preparation of bis [μ-chloro (methyl) pentamethylcyclopentadienylchrom (III)] (1)

a) Preparation of pentamethylcyclopentadienyllithium

In a 100 ml three-necked flask, 1.5 g (11.01 mmol) of pentamethylcyclopentadiene were first dissolved in 40 ml of tetrahydrofuran (THF) under a protective gas atmosphere. 7 ml (11.20 mmol) of a 1.6 M solution of butyllithium in pentane were slowly added dropwise to this solution. A yellow suspension was formed. The reaction mixture was heated under reflux to form an orange suspension, brought to room temperature and used as such in the following reaction step.

b) Preparation of bis [μ-chloro (methyl) pentamethylcyclopentadienylchrom (III)] (1)

3.98 g (10.62 mmol) of CrCl ₃ × 3 THF were initially weighed in under a protective gas atmosphere and suspended in 40 ml of THF. The pentamethylcyclopentadienyllithium suspension shown above was slowly added dropwise to this suspension. A blue-green solution formed which was stirred at room temperature for 1.5 h.

6.62 ml (10.62 mmol) of a 1.6 M solution of methylthium in diethyl ether were slowly added dropwise to this solution. A dark violet solution formed which was stirred at room temperature for 1.5 h.

The solvent was removed in vacuo and the residue was taken up in 20 ml of toluene

Reaction previously formed lithium chloride remained as a white sediment and was filtered off. After removal a dark purple solid was isolated from the toluene in vacuo and was dried in vacuo at 40.degree. The yield was 2.13 g.

ⁱ H-NMR (500 MHz, C ₆ D ₆ , T = 25 ° C):

- 9.307 ppm (s, 30 H, pentamethylcyclopentadienyl ligand) -41.976 ppm (s, 6 H, CH ₃ ligand)

Elemental analysis: CH ₃₆ ClCr ₂ (475.43 g / mol) calculated C: 55.39%, H: 7.61% found C: 53.45%, H: 7.55%

attempts to merge

Homopolymerization of norbornene

example 1

The metal complex (1) (25.3 mg; 0.05 mmol) was dissolved in 10 ml of toluene and 2 g (21.2 mmol) of norbornene was added.

3.0 ml of 1.53 M methylalumoxane solution (in toluene) were added to this mixture at a temperature of 25.degree. After 2 hours at this temperature, the polymerization was stopped by adding methanol. The polymer was filtered off, washed with methanol and added in vacuo

60 ° C dried. Yield 54%.

Example 2

The polymerization of norbornene was carried out analogously to Example 1, but the polymerization was carried out for 4 hours. After working up, 59% of polynorbornene was obtained.

Examples 3 to 7

The polymerization of norbornene was carried out by dissolving the metal complex (1) in 10 ml of toluene and adding the appropriate amount of norbornene according to Table 1. To this mixture was added methylalumoxane solution (1.53 M in toluene), so that the molar ratio to that used

Amount of metal complex was 100: 1. The polymerization temperature was 25 ° C. After 2 hours, the polymerization was stopped by adding methanol. The polymer was filtered off, washed with methanol and dried in vacuo at 60 ° C. Further information can be found in Table 1: Table 1

Copolymerization of norbornene with ethene

Examples 8 to 12

75.59 mg (0.159 mmol) of [CsMesCrMeCl] ₂ together with 5.0 g (53.1 mmol) of norbornene were weighed into a 50 ml glass autoclave with a pressure syringe under a protective gas atmosphere and dissolved in 10 ml of toluene. The pressure syringe was filled with 9.0 ml of MAO solution (1.53 M toluene), the autoclave was cooled to 0 ° C. and with ethene to an ethene pressure which was 0.25 bar lower than that shown in Table 2 Ethen end pressure, filled. The ethene pressure given in Table 2 was applied to the pressure syringe and the reaction was started by opening the pressure syringe. The ethene pressure applied was kept constant during the reaction time of 3 h. The reaction was stopped by adding a MeOH / HCl mixture and precipitated in excess methanol. The precipitated product was filtered off and dried in vacuo at 60 ° C. The dried samples were examined for crystalline components by means of X-ray wide-angle scattering. Reaction conditions and product parameters can be found in Tables 2 and 3.

Table 2

Number average molecular weight and distribution

M _w / M _n determined by means of GPC against polystyrene as

Standard n.a. not determined

Table 3

Ethene content determined by means of ¹ H-NMR spectroscopy (300 MHz, C ₆ D ₆ , T = 25 ° C) c) T _g determined by means of DSC

iii) Comparative examples

Preparation of (pentamethylcyclopentadienyl) methyl bis (tetrahydrofuran) chromium (III) hexafluoroarsenate (2)

600 mg (1.26 mmol) (1) were dissolved in a Schlenk vessel under a protective gas atmosphere by adding 20 ml of THF, a dark violet solution being formed. 561.5 mg (2.65 mmol) of sodium hexafluoroarsenate were added to this solution while stirring and the mixture was stirred at room temperature for 15 h. The mixture was then filtered and the filtrate was concentrated in vacuo to give a red-violet solid. The yield of (2) was 770 mg. Due to the sensitivity of the compound, the sample was used directly for the polymerization.

Homopolymerization of norbornene:

56.9 mg (0.1 mmol) (2) were dissolved in 10 ml of toluene under a protective gas atmosphere. A solution of 2 g (21.24 mmol) of norbornene in 5 ml of toluene was added to this solution. The mixture was stirred for 15 h, 5 ml of methanol were added and the mixture was concentrated to dryness in vacuo. Only the catalyst used was retained as a residue. No polymer product could be isolated. Copolymerization of norbornene with ethene:

5 g (53.1 mmol) of norbornene and 10 ml of toluene were added to 56.9 mg (0.1 mmol) (2) under a protective gas atmosphere in a glass autoclave. The glass autoclave was cooled to 0 ° C. and filled with ethene (2 bar). The mixture was stirred at 0 ° C. for 2 h while maintaining the ethene pressure. During this time the reaction mixture remained homogeneous. The ethylene pressure was then released, the apparatus was flushed with argon and the reaction was stopped by adding a mixture of 5 ml of HCl and 45 ml of ethanol. No polymer product could be obtained.

Claims

claims

1. Catalyst preparation, obtainable by mixing a metal complex of the general formula (A)

in which the substituents have the following meaning:

M independently of one another chromium, molybdenum or tungsten,

Z independently of one another fluorine, chlorine, bromine, iodine, hydrogen or Ci to C o alkyl,

R ¹ to R ^{5 are} independently hydrogen, Ci to

Cio-alkyl, unsubstituted or substituted by C - to Cio-alkyl, C ₃ - to C ₇ -cycloalkyl, C ₆ - to cis-aryl, substituted C ₆ - to cis-aryl, where 2 adjacent radicals together for 4 to 18 C-containing saturated or unsaturated cyclic groups can stand, or

Si (R ⁶ ) ₃ with

R ⁶ independently of one another Ci - to Cio-alkyl, C ₃ - to Cio-cycloalkyl or C ₆ - to Cis-aryl,

Y independently of one another are C 1 to C ₂ o alkyl, C ₃ to Cio-cycloalkyl, C ₆ to C ₈ aryl or aralkyl with 1 to 10 C atoms in the alkyl radical and 6 to 18 C atoms in the aryl radical,

and a compound (B) forming metallocenium ions in an inert liquid reaction medium. Catalyst preparation according to claim 1, obtainable by mixing a metal complex (A), wherein

M chrome,

R ¹ to R ⁵ independently of one another are hydrogen, Ci to C ₆ alkyl, unsubstituted or by Ci to

C ₆ -alkyl substituted C ₅ - to C ₇ -cycloalkyl, C ₆ - to cis-aryl, substituted C ₆ - to cis-aryl, whereby also two neighboring residues together for 4 to 15 C-atoms have saturated or unsaturated cyclic groups can stand, or

Si (R ⁶ ) ₃ with

R ^{6 is} independently Ci to C ₆ alkyl, C ₃ to C ^■ ₆ cycloalkyl or C ₆ - to Cio-aryl, and

independently of one another Ci to Cio alkyl, C ₃ to C ₆ cycloalkyl, C ₆ to Cis aryl or aralkyl with 1 to 6 C atoms in the alkyl radical and 6 to 15 C atoms in the aryl radical

mean.

3. Catalyst preparation according to claims 1 and 2, obtainable by mixing metal complex (A) with metallocenium ion-forming compounds (B), selected from the group of open-chain and / or cyclic alumoxane compounds of the general formulas (B-I) or (B-II)

R ⁷

wherein R ⁷ independently of one another denotes a C 1 -C 4 -alkyl group and

m represents an integer from 5 to 30.

4. Catalyst preparation according to claims 1 to 3, obtainable by mixing metal complex (A), wherein

M independently of one another chromium, molybdenum or wolf - ram,

Z independently of one another chlorine, bromine or iodine,

Cio-alkyl substituted C ₅ - to C ₇ -cycloalkyl, C ₆ - to cis-aryl, substituted C ₆ - to cis-aryl, whereby also two neighboring residues together for 4 to 15 C-atoms have saturated or unsaturated cyclic Groups can stand, or

Si (R ⁶ ) ₃ with

Y independently of one another Ci to Cio alkyl, C ₃ - to

C ₆ -cycloalkyl, C ₆ - to cis-aryl or aralkyl with 1 to 10 C atoms in the alkyl radical and 6 to 15 C atoms in the aryl radical,

with a metallocenium ion-forming compound (B), which is an ionic compound with Lewis acid cations of the general formula

_G l + ( _T χlχ2χ3χ4) ^" ₁ (B - I II)

represents what

G represents an element of main group I or II of the Periodic Table of the Elements,

T an element of III. Main group of the periodic table of the elements means X ¹ to X ⁴ independently of one another for hydrogen, linear or branched Ci to C o alkyl, substituted Ci to C ₂ o alkyl, C ₆ to Cis aryl, substituted C ₆ to Cis aryl, aralkyl with 1 to 10 carbon atoms in the alkyl radical and 6 to 18 carbon atoms in the aryl radical,

Fluorine, chlorine, bromine, iodine, Ci to C ₂ o-alkoxy or C ₆ - to Cis-aryloxy, and

1 means 1 or 2.

5. Catalyst preparation according to claims 1 and 2, obtainable by mixing metal complex (A), wherein

M independently of one another chromium, molybdenum or tungsten,

Z independently of one another hydrogen or Ci bis

C ₂₀ alkyl,

R ¹ to R ⁵ independently of one another hydrogen, Ci to C ₆ -

Alkyl, unsubstituted or substituted by Ci- to Cio-alkyl C ₅ - to C ₇ -cycloalkyl, C ₆ ^■ to cis-aryl, with 2 adjacent radicals together for 4 to 15 C-atoms having saturated or unsaturated cyclic groups can stand, or Si (R ⁶ ) ₃ with

R ⁶ independently of one another are C 1 to C ₆ alkyl, C ₃ to C ₆ cycloalkyl or C ₆ Cio aryl,

Y Ci to Cio alkyl, C ₃ to C ₆ cycloalkyl, C ₆ to

Cis-aryl or aralkyl with 1 to 10 C atoms in the alkyl radical and 6 to 15 C atoms in the aryl radical,

mean with a metallocenium ion-forming compound (B), which is a strong, neutral Lewis acid of the general formula

TX ⁵ X ⁶ X ⁷ (B-IV)

represents what

T an element of III. Main group of the periodic table of the elements and X ⁵ , X ⁶ , X ^{7 are} independently hydrogen, Ci to C ₂ o -alkyl, substituted Ci- to C o -alkyl, C ₆ - to Cis-aryl, substituted C ₆ - to Cis-aryl, aralkyl with 1 to 10 carbon atoms in the alkyl radical and 6 to 18 carbon atoms in the aryl radical or fluorine, chlorine, bromine or iodine,

mean.

6. Use of the catalyst preparations according to claims 1 to 5 for the production of olefin (co) polymers.

7. A process for the preparation of olefin (co) polymers from cycloolefinic and / or α-olefinic monomer units, characterized in that the polymerization is carried out at a temperature in the range from -50 to 150 ° C in the presence of a catalyst system, which as active constituents is a metal complex of the general formula (A)

wherein

M independently of one another chromium, molybdenum or tungsten,

Z independently of one another fluorine, chlorine, bromine, iodine,

Hydrogen or Ci to C ₂ o-alkyl,

R ¹ to R ^{5 are} independently hydrogen, Ci to

Cio-alkyl, unsubstituted or substituted by Ci- to Cio-alkyl C ₃ - to C ₇ -cycloalkyl, C ₆ to Cis-aryl, substituted C ₆ - to Cis-aryl, where also 2 adjacent radicals together for 4 to 18 C. - Saturated or non-atomic saturated cyclic groups can stand, or Si (R ⁶ ) ₃ with

R ⁶ independently of one another Ci to Cio-alkyl, C ₃ - to Cio-cycloalkyl or C ₆ - to Cis-aryl, and

Y independently of one another are C 1 -C ₂₀ -alkyl, C ₃ - bis

Cio-cycloalkyl, C ₆ - to cis-aryl or aralkyl with 1 to 10 C atoms in the alkyl radical and 6 to 18 C atoms in the aryl radical

mean, and has a metallocenium ion-forming compound (B).

8. The method according to claim 7, characterized in that in the metal complex (A)

M independently of one another chromium, molybdenum or tungsten,

chlorine, bromine or iodine independently of one another,

R ¹ to R ^{5 are} independently hydrogen, Ci to

C ₆ alkyl, unsubstituted or substituted by Ci to Cio alkyl C ₃ to C ₇ cycloalkyl, C ₆ to Cis aryl, substituted C ₆ to C ₈ aryl, where 2 adjacent radicals together for 4 up to 15 carbon atoms can have saturated or unsaturated cyclic groups, or Si (R ⁶ ) ₃ with

Y independently of one another Ci to Cio alkyl, C ₃ - to

and in the compounds (B-I) or (B-II) forming metallocenium ions

R ⁷ independently of one another denotes a C 1 -C ₄ -alkyl group and

m represents an integer from 5 to 30.

9. The method according to claims 7 and 8, characterized in that a compound is used as the metal complex (A) in which

M independently of one another chromium, molybdenum or tungsten,

Z independently of one another chlorine, bromine or iodine,

R ¹ to R ^{5 are} independently hydrogen, Ci to

C ₆ alkyl, unsubstituted or substituted by C ₁ to C 10 alkyl, C ₃ to C cycloalkyl, C ₆ to Cis aryl, substituted C ₆ to Cis aryl, with 2 adjacent radicals together for 4 to 15 Saturated or unsaturated cyclic groups containing C atoms, or Si (R ⁶ ) ₃ with

Y independently of one another are C 1 to C 10 alkyl, C ₃ to C ₆ cycloalkyl, C ₆ to Cis aryl or aralkyl having 1 to 10 C atoms in the alkyl radical and 6 to 15 C atoms in the aryl radical,

and as metallocenium ion-forming compounds (B) ionic compounds with Lewis acid cations of the general formula (B-III)

in the

T an element of III. Main group of the periodic table of the elements means

X ¹ to X ⁴ independently of one another for hydrogen, linear or branched Ci to C ₂ o alkyl, substituted Ci to C ₂ o alkyl, C ₆ to Cis aryl, substituted C ₆ to Cis aryl, aralkyl with 1 to 10 carbon atoms in

Alkyl radical and 6 to 18 carbon atoms in the aryl radical, Fluorine, chlorine, bromine, iodine, Ci to C ₂ o-alkoxy or C ₆ - to Cis-aryloxy, and

1 means 1 or 2,

starts.

10. The method according to claim 7, characterized in that in

Metal complex (A) which have the following meanings:

M independently of one another chromium, molybdenum or tungsten,

Z independently of one another are hydrogen or C 1 -C ₂₀ -alkyl,

R ¹ to R ⁵ independently of one another are hydrogen, Ci to C ₆ alkyl, unsubstituted or substituted by C ₁ to C 10 alkyl, C ₃ to C ₇ cycloalkyl, C ₆ to C ₅ aryl, substituted C ₆ to Cis-aryl, where 2 adjacent radicals together can represent saturated or unsaturated cyclic groups having 4 to 15 carbon atoms, or Si (R ⁶ ) ₃ with

Y Ci to Cio alkyl, C ₃ to C ₆ cycloalkyl, C ₆ to Cis aryl or aralkyl with 1 to 10 C atoms in

Alkyl radical and 6 to 15 carbon atoms in the aryl radical,

and as the metallocenium ion-forming compound (B), a strong, neutral Lewis acid of the general formula

TX ⁵ X ⁶ X ⁷ (B-IV),

in which the substituents have the following meaning:

T an element of III. Main group of the periodic table of the elements and

X ⁵ , X ⁶ , X ^{7 are} independently hydrogen, Ci to C ₂ o -alkyl, substituted Ci to C o -alkyl, C ₆ to Cis-aryl, substituted C ₆ to Cis-aryl, aralkyl with 1 to 10 Carbon atoms in the alkyl radical and 6 to 18 carbon atoms in the aryl radical or fluorine, chlorine, bromine or iodine,

used.

11. The method according to claims 7 to 10, characterized in that there are used as cycloolefinic monomer units norbornene, cyclopentene, cyclohexene, cyclooctene or cyclododecene and as α-olefinic monomer units ethene, propene, butene, hexene, octene or decene.