WO2006048634A1

WO2006048634A1 - Polymerisation catalysts

Info

Publication number: WO2006048634A1
Application number: PCT/GB2005/004221
Authority: WO
Inventors: Vernon Charles Gibson; Grant Berent Jacobsen; Atanas Kostadinov Tomov
Original assignee: Ineos Europe Limited
Priority date: 2004-11-04
Filing date: 2005-11-01
Publication date: 2006-05-11
Also published as: GB0424422D0

Abstract

A supported transition metal complex comprising (a) a vanadium metal complex having at least one atom selected from boron, nitrogen, oxygen, phosphorus, sulphur and selenium, covalently bonded to (b) a particulate inorganic support material. The support material and complex have complimentary groups, eg -OH and alkylsilyl, which react to form a covalent bond to fix the complex on the support. The complexes are useful for making catalysts, preferably with an organoaluminium or organoboron cocatalyst, for polymerisation of olefinic monomers. The complex ligands preferably contain an imidazole group coordinated to the transition metal.

Description

POLYMERISATION CATALYSTS

Commodity polyethylenes are commercially produced in a variety of different types and grades. Homopolymerisation of ethylene with transition metal based catalysts leads to the production of so-called "high density" grades of polyethylene. These polymers have relatively high stiffness and are useful for making articles where inherent rigidity is required. Copolymerisation of ethylene with higher 1 -olefins (eg butene, hexene or octene) is employed commercially to provide a wide variety of copolymers differing in density and in other important physical properties. Particularly important copolymers made by copolymerising ethylene with higher 1 -olefins using transition metal based catalysts are the copolymers having a density in the range of 0.91 to 0.93. These copolymers which are generally referred to in the art as "linear low density polyethylene" are in many respects similar to the so-called "low density" polyethylene produced by the high pressure free radical catalysed polymerisation of ethylene. Such polymers and copolymers are used extensively in the manufacture of flexible blown film. Polypropylenes are also commercially produced in a variety of different types and grades. Homopolymerisation of propylene with transition metal based catalysts leads to the production of grades with a wide variety of applications. Copolymers of propylene with ethylene or terpolymers with ethylene and higher 1 -olefins are also useful materials. In recent years the use of certain metallocene catalysts (for example biscyclopentadienylzirconiumdichloride activated with alumoxane) has provided catalysts with potentially high activity. Other derivatives of metallocenes have been shown to be potentially useful for producing polypropylene with good activity, molecular weight and tacticity control. However, metallocene catalysts of this type suffer from a number of disadvantages, for example, high sensitivity to impurities when used with commercially available monomers, diluents and process gas streams, the need to use large quantities of expensive alumoxanes to achieve high activity, difficulties in putting the catalyst on to a suitable support and synthetic difficulties in the production of more complex catalyst structures suitable for polymerising propylene in a tactic manner.

Another type of catalyst system disclosed, for example, in EP 1238989 is based on (A) a transition metal compound or lanthanoid compound containing two or more atoms selected from the group consisting of boron, nitrogen, oxygen, phosphorus, sulfur, and selenium; and (B) a Lewis acid. Transition metal complexes of the type disclosed in EP1238989 can be activated to form highly active polymerisation catalysts using the special activators disclosed in EP1238989 or using alumoxanes or alkylboron compounds as activators. It is highly desirable to use catalysts of this type on supports, especially inorganic supports, for example, silica, alumina, and magnesium chloride. Although the latter are perhaps the most frequently used inorganic support materials there are also many other relatively inert inorganic solid substances that can be employed in this manner.

In many commercial processes for the production of polyolefins it is desirable to use a polymerisation catalyst which is supported on an inorganic support material. For example, the use of supported catalysts under gas phase or slurry phase process conditions enables good control of particle morphology and the bulk density of the produced polymer. The use of supported catalysts also provides increased bulk density leading to increased production rate per reactor unit volume. Also, the use of properly supported catalysts can reduce reactor fouling. However, certain catalysts are difficult to support or become detached from the support during use in polymerisation processes. Failure to support the catalyst in a stable manner renders it useless for many commercial polymerisation processes. Detachment of the catalyst from the support during polymerisation can lead to poor morphology of the produced polymer and / or to reactor fouling.

There have been a number of attempts in the prior art to provide supported catalysts comprising a catalyst complex chemically bonded to a support material. US 2002/0187892 relates to a method for forming supported late transition metal olefin polymerisation catalysts by supporting a transition metal complex having a reactive functional group on a support having a complementary reactive functional group.

US 633160 IB relates to a process for making a supported single site polymerization catalyst. The transition metal of the catalyst is tethered through a bridged, bidentate ligand that is covalently bound to the support. The catalyst is prepared in a two step process that involves preparation of a supported ligand from an amine-functionalised support, followed by reaction of the supported ligand with a transition metal compound to give the "tethered" catalyst. EPl 134225 relates to the. preparation of supported catalysts for polymerizing olefins comprising the product of reacting certain functionalized diimino compounds with a reactive support material, and then treating the product with a Group 8, 9 or 10 transition metal. The diimine is group is functionalized with a silyl group which reacts with the support.

WO2000056786 relates to non-ionic (neutral) late transition metal catalysts that are covalently bound to an inert support through a molecular tether. The catalyst is represented by the formula

S-T-Cat wherein

"S" represents an inert support or surface modified support material, "t" represents a C₂ - C₄₀ hydrocarbylene, C₂ - C₄₀ hydrocarbyloxyene, C₂ - C₄0 fluorinated hydrocarbylene, silyloxyl-functionalised C₂ - C₄₀ hydrocarbylene, or borane- fiinctionalized hydrocarbylene which is covalently bonded to both the "S" and to the catalyst group "Cat", and "Cat" represents a non-ionic (neutral) late transition metal chelate. The transition metals disclosed in WO2000056786 are Group 8 transition metals selected from Fe, Co, Ni, Ru, Pd, Os. Ir, Pt (preferably in +2 oxidation state) or Ti, Zr or Hf (preferably in the +4 oxidation state). Ni and Pd are preferred.

Hitherto is has been very difficult to satisfactorily support transition metal complexes of vanadium on a support material. The complexes do not bind well to support materials. Applicants have now found that by suitable selection of special vanadium complexes it is possible to form useful supported catalysts based on vanadium complexes.

It is an object of the present invention is to provide a novel supported transition metal complex comprising a vanadium complex which can be used, preferably with an activator, for polymerising unsaturated monomers. A further object of the present invention is to provide a process for making the novel supported catalysts system. A further object is to provide supported catalyst system and to provide a process for polymerising monomers, for example, olefins, and especially for polymerising ethylene alone or propylene alone, or for copolymerising ethylene with higher 1 -olefins with high activity.

The present invention provides a novel supported transition metal complex comprising a) a vanadium metal complex comprising at least one atom selected from boron, nitrogen, oxygen, phosphorus, sulphur and selenium, covalently bonded to b) a particulate inorganic support material. A further aspect of the present invention provides a process for preparing the novel supported transition metal complex comprising reacting together c) a vanadium complex precursor comprising at least one atom selected from boron, nitrogen, oxygen, phosphorus, sulphur and selenium, and having at least one functional group capable of reacting with d) a functional group on a solid particulate support material to form at least one covalent bond.

The transition metal complex of the present invention comprises vanadium alone or vanadium together with one or more other transition metals.

By "covalently bonded" is meant throughout this specification that at least 50 weight %, preferably at least 80 wt %, most preferably at least 90 wt % of the molecules of the transition metal complex have at least one covalent bond connecting them to the support material.

By the term" vanadium complex" is meant a vanadium atom having one or more ligands bonded thereto. The transition metal complex can be a neutral complex or an ionic complex. Preferably the defined atom (ie the one selected from boron, nitrogen, oxygen, phosphorus, sulphur and selenium) chemically bonds the ligand to the transition metal. The transition metal complex precursor is hereinafter called "the precursor". The chemical bond connecting the transition metal complex to the support material can be a direct bond between a carbon atom in the complex and the support material, or a direct bond between a hetero atom in the complex and the support, or a direct bond from the transition metal to the support.

The transition metal complex of the present invention is preferably a non- metallocene complex.

Preferably the transition metal complex contains at least two atoms selected from boron, nitrogen, oxygen, phosphorus, sulphur and selenium. More preferably the complex contains two or more nitrogen atoms; or a nitrogen and an oxygen atom; or a phosphorus and an oxygen atom; these atoms being optionally together with one or more other atoms selected from boron, nitrogen, oxygen, phosphorus, sulphur and selenium.

The transition metal complex is chemically bonded to the support material by reacting together a transition metal complex precursor having one or more functional groups that react with functional groups on the support material to form the chemical bonds. Preferably the bonding is by means of covalent bonds. For the avoidance of doubt, mere absorption is not regarded as chemical bonding throughout this specification.

The functional group on the transition metal complex precursor capable of reacting with the support material is preferably selected from hydroxyl, acetal, ketal, tertiaryalkoxyalkyl, benzoyloxyalkyl, monothioacetal, monothioketal and reactive silicon containing groups. Examples of suitable reactive silicon-containing groups are those represented by the formula -Si(OR)_n (X)_m (R)_p wherein n, m and p can each be 0, 1, 2 or 3 provided that n+m+p = 1 to 3, R is hydrocarbyl, preferably C₁ to C₁₀ alkyl, most preferably methyl, ethyl or n-propyl, X is halogen, preferably Cl or F. If desired the support material can be modified to provide suitable functionality complimentary to the functionality on the transition metal compound to provide a desired covalent bond between the support and the transition metal complex. Suitable pairs of complementary functional groups are shown in the following table:

The support material employed in the present invention is suitably any support material capable of forming a covalent bond with the transition metal complex. Examples of suitable support materials are silica, alumina, zirconia, magnesia, calcium carbonate, natural or synthetic clays, talc, and magnesium chloride. Silica is preferred.

The support preferably has a particle size in the range 0.1 - 1000 micron preferably 1- 250 micron. The particles are preferably spheroidal in shape. The quantity of the transition metal complex relative to support material is preferably such as to provide a weight ratio of transition metahsupport material in the range 1:1,000,000 to 1 : 1, more preferably 1:10000 to 1:10..

The reactive functional group on the support material employed in the process for making the supported transition metal complex can be, for example, a surface siloxane group, -Cl, -OH, a reactive organometal group or any other group capable of being displaced to form a covalent bond with the support substrate. Silica is particularly preferred, especially silica that has been heated to a temperature above 600⁰C to eliminate a substantial quantity of the surface hydroxyl groups to form reactive surface siloxane groups. In a preferred embodiment of the present invention the support material is an inorganic oxide support material, preferably silica or alumina, most preferably silica that has been dried to render it free from absorbed water. Preferably the silica is heated to a temperature sufficiently high to cause the formation of highly reactive siloxane groups. The hydroxyl groups and/or the reactive siloxane groups on the silica support material can be reacted functional groups on the transition metal complex precursor to form the supported transition metal complexes of the present invention

The support material employed in the process of the present invention can, if desired, be chemically modified prior to reacting it with the transition metal complex precursor. For example, an inorganic oxide support material bearing surface hydroxyl groups, for example, silica, alumina or magnesia, can be reacted with a reactive metal alkyl, for example aluminium or magnesium alkyl to provide a support having surface organometallic groups, for example, -M-R groups wherein M is the metal and R is an alkyl group having 1 to 10, preferably 1 to 3 carbon atoms. The support material, so modified; can be reacted, for example, with a transition metal complex precursor having a hydroxyl functional group to form the desired covalent bond. For example a silica support can be reacted with triethylaluminium to yield a support with surface -Al-Et₂ groups. This could then be reacted with a transition metal complex precursor containing, for example, an OH group to form a bond to the surface of the support material and the elimination of volatile ethane by product.

The transition metal compound precursors employed in the process of the present invention preferably have the general formula of Formula A below:

FG

Ligand A ] M(X)_y(L)_z ' Formula A n

wherein "Ligand A" is a mono-, di- , tri- or tetradentate organic ligand having one or more functional groups "FG" capable of reaction with a reactive group on an inorganic support to form a covalent bond, X is an anionic group, L is a ligand or neutral donor group; n is 1 , 2 ,3 or 4, y and z are independently zero or integers such that the number of Ligand, X and L groups satisfy the valency and oxidation state of the metal M. The metal M is either solely vanadium, or a mixture of vanadium with one or more other transition metals. In a first preferred embodiment of the present invention "Ligand A" in Formula A is represented by the bidentate group having Formula B

Formula B

wherein the monovalent groups R¹ and R² are independently selected from -R^a, -OR^b,

-NR^cR^d, and-NHR^e: the monovalent groups R^a, R^b, R^c, R^d, and R^e, and the divalent group R³ are independently selected from (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic B2005/004221

hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups and (vi) heterosubstituted derivatives of said groups (i) to (v);

M is vanadium or vanadium and a metal from Group 3 to 11 of the Periodic Table or a lanthanide metal; E is phosphorus or arsenic; X is an anionic group, L is a neutral donor group; n is 1 or 2, y and z are independently zero or integers such that the number of X and

L groups satisfy the valency and oxidation state of the metal M and "FG" is a substituent functional group pendant from at least one of the groups R¹, R² and R³.

FG is preferably selected from hydroxyl, acetal, ketal, tertiaryalkoxyalkyl, benzoyloxyalkyl, monothioacetal, monothioketal and reactive silicon containing groups. Examples of suitable reactive silicon-containing groups are those represented by the formula -Si(OR)_n (X)_m (R)_p wherein n, m and p can each be 0, 1, 2 or 3 provided that n+m+p = 1 to 3, R is hydrocarbyl, preferably C₁ to C₁₀ alkyl, most preferably methyl, ethyl or n-propyl, X is halogen, preferably Cl or F.

Thus a preferred transition metal complex precursor employed in the process of the present invention preferably has the Formula C

Formula C

wherein the monovalent groups R¹ and R² are independently selected from -R^a, -OR^b, -NR^cR^d, and~NHR^e: the monovalent groups R^a, R^b, R^c, R^d, and R^e, and the divalent group R³ are independently selected from (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups and (vi) heterosubstituted derivatives of said groups (i) to (v); M is vanadium, or vanadium and a metal from Group 3 to 11 of the Periodic Table or a lanthanide metal; E is phosphorus or arsenic; X is an anionic group, L is a neutral donor group; n is 1 or 2, y and z are independently zero or integers such that the number of X and L groups satisfy the valency and oxidation state of the metal M and "FG" is a substituent functional group pendant from at least one of the groups R¹, R² and R³.

The monovalent groups R^a, R^b, R^c, R^d, and R^e, and the divalent group R³ are defined above as (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups, (vi) heterosubstituted derivatives of said groups (i) to (v). These defined groups preferably contain 1 to 30, more preferably 2 to 20, most preferably 2 to 12 carbon atoms. Examples of suitable monovalent aliphatic hydrocarbon groups are methyl, ethyl, ethenyl, butyl, hexyl, isopropyl and tert-butyl. Examples of suitable monovalent alicyclic hydrocarbon groups are adamantyl, norbornyl, cyclopentyl and cyclohexyl. Examples of suitable monovalent aromatic hydrocarbon groups are phenyl, biphenyl, naphthyl, phenanthryl and anthryl. Examples of suitable monovalent alkyl substituted aromatic hydrocarbon groups are benzyl, tolyl, mesityl, 2,6-diisopropylphenyl and 2,4,6-triisopropyl. Examples of suitable monovalent heterocyclic groups are 2-pyridinyl, 3-pyridinyl, 2-thiophenyl, 2- furanyl, 2-pyrrolyl, 2-quinolinyl. As regards the divalent group R³, this, for example, can be selected from any of the aforementioned monovalent groups wherein one of the hydrogen atoms on the said monovalent group is replaced by a valency bond to form the second bond on the divalent group R³.

Suitable substituents for forming heterosubstituted derivatives of said groups R^a, R^b, R^c, R^d, R^e and R³ are, for example, chloro, bromo, fluoro, iodo, nitro, amino, cyano, alkoxy, mercapto, hydroxyl and silyl. Examples of alkoxy groups are methoxy, ethoxy, phenoxy (i.e. -OC₆Hs), tolyloxy (i.e. -OC₆Pl₄(CHs)), xylyloxy, mesityloxy. Examples of amino groups are dimethylamino, diethylamino, methylethylamino. Examples of mercapto groups are thiomethyl, thiophenyl. Examples of silyl groups are trimethylsilyl and triethylsilyl. Examples of suitable heterosubstituted derivatives of said groups (i) to (v) are 2-chloroethyl, 2-bromocyclohexyl, 2-nitrophenyl, 4-ethoxyphenyl, 4-chloro-2-pyridinyl, 4- dimethylaminophenyl and 4-methylaminophenyl.

R¹ and R² can, if desired, form a single integral divalent group R⁴, wherein R⁴ is independently selected from the divalent groups -R^a'- , -O-R^b'- , -O-R^b'-O- , -N-(R^c)R^d'- , -N(R⁰)- , -N(R^C)-R^d'-N(R> , -Si(R^c)₂-R^a'-Si(R^c)₂- , and -Si(RV 5 and wherein the divalent groups R^a , R^b , and R^d are independently selected from divalent (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups and (vi) heterosubstituted derivatives of said groups (i) to (v), and R° is as defined above.

Although R¹ and R² can form integral unit R⁴ it is preferred that they are separate groups. Preferably R¹ and R² are separate, identical groups. Preferably, R¹ and R² are separate, identical aliphatic hydrocarbon, alicyclic hydrocarbon, aromatic hydrocarbon or alkyl substituted aromatic hydrocarbon groups.

When n = 2, there are two phosphorus or arsenic-containing ligands on the transition metal M. Under these circumstances there are two separate R¹ groups ( R¹ and R¹ ) and two separate R² groups (R² and R² ). It is preferred that at least one of the pairs of these groups, R¹ and R¹ or R² and R² are linked. For example, R¹' and R^1" can be linked to form R⁵ as illustrated in Formula D below.

Formula D

The divalent group R⁵ is preferably selected from the divalent groups recited above for the divalent group R⁴. At least one of the groups R¹ , R¹ , R^2', R² and R⁵ has a pendant functional group "FG" as defined above. The groups R¹ , R^{1 "}, R² , R^2" and R⁵ are otherwise as defined above.

M is either vanadium alone, or a mixture of vanadium with one or more Group 3 to 11 transition metal, more preferably Group 5 to 7 transition metal. Most preferably M is vanadium alone.

Examples of groups suitably used as the divalent group R⁵ are -CH₂-, -CH₂CH₂-, -CH₂CH₂CH₂-, tr<ms-l,2-cyclopentane, trarø-l,2-cyclohexane, 2,3-butane, l,l'-biphenyl, U'-binaphthyl, -N(Me)-, -N(Et)-, U'-biphenol and -Si(Me)₂-.

The divalent group R³ is defined above as independently selected from (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups and (vi) heterosubstituted derivatives of said groups (i) to (v);. It is preferred that R³ is an alkyl substituted or heterosubstituted aromatic hydrocarbon group. More preferably R³ is an alkyl substituted or heterosubstituted divalent 1,2-phenylene group. The 1,2-phenylene group preferably has the said alkyl substituent or hetero atom in the position ortho to the ring-carbon atom bonded to the oxygen atom in Formula C. The 1,2-phenylene group is optionally substituted in one of more of the other remaining positions of the 1,2-phenylene group.

When any of the defined monovalent groups R^a, R^b, R^c, R^d, and R^e, and the divalent groups R^a , R^b , R^d , R³, R⁴, and R⁵ are heterocyclic, the atom or atoms present in the rings as the heteroatom can be, for example, oxygen, nitrogen, sulphur, phosphorus or silicon. E is preferably phosphorus. The anionic group X can be, for example, a halide, preferably chloride or bromide; or a hydrocarbyl group, for example, methyl, benzyl or phenyl; a carboxylate, for example, acetate or acetylacetate; an oxide; an amide, for example diethyl amide; an alkoxide, for example, methoxide, ethoxide or phenoxide; an acetylacetonate; or a hydroxyl. Or, for example, X can be a non-coordinating or weakly-coordinating anion, for example, tetrafluoroborate, a fluorinated aryl borate or a triflate. The anionic groups X may be the same or different and may independently be monoanionic, dianionic or trianionic.

The neutral donor group L can be, for example, a solvate molecule, for example diethyl ether or THF (tetrahydrofuran); an amine, for example, diethyl amine, trimethylamine or pyridine; a phosphine, for example trimethyl phosphine or triphenyl phosphine; an olefin; water; a conjugated or non-conjugated diene.

The value of y in Formulae A, C and D depends on the value of n, the charge on the anionic group X and the oxidation state of the metal M. For example, if M is vanadium alone in oxidation state +3 and n is 2, then y is 1. If M is vanadium alone in the oxidation state of +3 and n is 1, then y is 2. IfM comprises one or more other transition metals, then the stoicheiometry of the Formulae can be worked out for each of the separate metals. For example, if M is titanium in oxidation state +4 and n is 2, then y is 2 if X is a monoanionic group (eg. chloride) or y is 1 if X is a dianionic group (eg. oxide); if M is titanium in oxidation state +4 and n is 1, then y is 3 if all X groups are monoanionic groups (eg. chloride) or y is 2 if one X group is a dianionic group (eg. oxide) and the other is monoanionic. It is preferred that n is 2.

Particularly preferred complex precursors are those having the formulae

wherein at least one functional group "FG" (as defined above) is pendant from at least one of the phenyl and / or ortho-phenylene groups, and / or from the linkage group corresponding to R⁵ in Formula D ie from the C₂ group connecting the two phosphorus atoms. For example, the functional groups FG can be present as follows:

In a second preferred embodiment of the present invention "Ligand A" in Formula A is represented by the tridentate group having Formula E*

Formula E*

wherein Z comprises a fϊve-membered heterocyclic group, the five membered heterocyclic group containing at least one carbon atom, at least one nitrogen atom and at least one other hetero atom selected from nitrogen, sulphur and oxygen, the remaining atoms in said ring being selected from nitrogen and carbon; M is solely vanadium or a mixture of vanadium and a metal from Group 3 to 11 of the Periodic Table or a lanthanide metal; K¹ and K² are divalent groups independently selected from (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups and (vi) heterosubstituted derivatives of said groups (i) to (v); D¹ and D² are donor atoms or groups; X is an anionic group, L is a neutral donor group; n = m = zero or 1; y and z are independently zero or integers such that the number of X and L groups satisfy the valency and oxidation state of the metal M and "FG" is a substituent functional group,as defined above, pendant from at least one of the groups D¹, D², K¹, K² and Z.

Thus, a preferred transition metal complex precursor employed in the process of the present invention preferably has the Formula E

wherein Z comprises a five-membered heterocyclic group, the five membered heterocyclic group containing at least one carbon atom, at least one nitrogen atom and at least one other hetero atom selected from nitrogen, sulphur and oxygen, the remaining atoms in said ring being selected from nitrogen and carbon; M is solely vanadium or a mixture of vanadium and metal from Group 3 to 11 of the Periodic Table or a lanthanide metal; K¹ and K² are divalent groups independently selected from (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups and (vi) heterosubstituted derivatives of said groups (i) to (v); D¹ and D² are donor atoms or groups; X is an anionic group, L is a neutral donor group; n = m = zero or 1; y and z are independently zero or integers such that the number of X and L groups satisfy the valency and oxidation state of the metal M, and "FG" is a substituent functional group,as defined above, pendant from at least one of the groups D¹, D², K¹, K² and Z.

Preferably FG is pendant from D¹ and / or D². FG is preferably selected from hydroxyl, acetal, ketal, tertiaryalkoxyalkyl, benzoyloxyalkyl, monothioacetal, monothioketal and reactive silicon containing groups. Examples of suitable reactive silicon-containing groups are those represented by the formula -Si(OR)_n (X)_m (R)_P wherein n, m and p can each be 0, 1, 2 or 3 provided that n+m+p = 1 to 3, R is hydrocarbyl, preferably C₁ to C_1O alkyl, most preferably methyl, ethyl or n-propyl, X is halogen, preferably Cl or F. Preferably the divalent groups K¹ and K² are not linked other than through the donor atom or group D¹.

At least one of the atoms present in the ring of the fϊve-membered heterocyclic group Z is preferably bonded directly to K¹ and preferably a second atom in the ring is bonded directly to M. Most preferably the atom in the fϊve-membered ring bonded directly to K¹ is adjacent to a second atom in said ring, said second atom being bonded directly to M.

The five-membered heterocyclic group Z preferably contains at least 2 carbon atoms in its ring and more preferably at least 3 carbon atoms in its ring. Examples of suitable 5-membered heterocyclic groups are (but are not restricted to):

When the 5-membered heterocyclic group is selected from the above formulae, at least one of the hydrogen atom substituents thereon is substituted by a functional group FG as defined above.

In a further preferred embodiment of the present invention Z, in Formula E, is specifically an imidazole-containing group. Under these circumstances the imidazole- containing group Z is preferably a group of Formula I, π or III wherein at least one of the substituents R¹ to R^π has a pendant functional group "FG" as hereinbefore defined.

R¹ to R¹¹ are independently hydrogen or a monovalent (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups, (vi) heterosubstituted derivatives of said groups (i) to (v), and (vii) hydrocarbyl-substituted heteroatom groups. The "free" valence bond on the left of Formulae I, II and IQ provides at least one of the links of K into the rest of Formula E. The other link or links are preferably provided by at least one of the nitrogen atoms in the imidazole-containing group. These defined groups R^! to R^{1 !} preferably contain 1 to 30, more preferably 2 to 20, most preferably 2 to 12 carbon atoms. Examples of suitable aliphatic hydrocarbon groups are methyl, ethyl, ethylenyl, butyl, hexyl, isopropyl and tert- butyl. Examples of suitable alicyclic hydrocarbon groups are adamantyl, norbornyl, cyclopentyl and cyclohexyl. Examples of suitable aromatic hydrocarbon groups are phenyl, biphenyl, naphthyl, phenanthryl and anthryl. Examples of suitable alkyl substituted aromatic hydrocarbon groups are benzyl, tolyl, mesityl, 2,6-diisopropylphenyl and 2,4,6- triisopropyl. Examples of suitable heterocyclic groups are 2-pyridinyl, 3-pyridinyl, 2- thiophenyl, 2-furanyl, 2-pyrrolyl, 2-quinolinyl. Suitable substituents for forming heterosubstituted derivatives of said groups R¹ to R^u are, for example, chloro, bromo, fluoro, iodo, nitro, amino, cyano, ether, hydroxyl and silyl, methoxy, ethoxy, phenoxy (i.e. -OC₆H5), tolyloxy (i.e. -OCeH₄(CHs)), xylyloxy, mesityloxy, dimethylamino, diethylamino, methylethylamino, thiomethyl, thiophenyl and trimethylsilyl. Examples of suitable heterosubstituted derivatives of said groups (i) to (v) are 2-chloroethyl, 2- bromocyclohexyl, 2-nitrophenyl, 4-ethoxyphenyl, 4-chloro-2-pyridinyl, 4- dimethylaminophenyl and 4-methylaminophenyl. Examples of suitable hydrocarbyl- substituted heteroatom groups are chloro, bromo, fluoro, iodo, nitro, amino, cyano, ether, hydroxyl and silyl, methoxy, ethoxy, phenoxy (i.e. -OC₆H₅), tolyloxy (i.e. -OCeH₄(CHs)), xylyloxy, mesityloxy, dimethylamino, diethylamino, methylethylamino, thiomethyl, thiophenyl and trimethylsilyl. Any of the substituents R¹ to R¹¹ may be linked to form cyclic structures. Substituents R² to R¹¹ may also suitably be inorganic groups such as fluoro, chloro, bromo, iodo, nitro, amino, cyano and hydroxyl. Further suitable imidazole-containing groups may be obtained by removal of substituent R¹, for example by deprotonation when R¹ is hydrogen, to give formally monoanionic imidazole-containing groups.

It is preferred that the imidazole-containing group has a structure described in Formula in (a "benzimidazole"). At least one of the substituent R⁸ to R¹¹ groups is preferably the functional group "FG". R¹ is preferably hydrogen, an aliphatic hydrocarbon group, an aromatic hydrocarbon group or is removed to give a formally monoanionic benzimidazole group. The remaining R⁸ to R¹¹ groups are preferably hydrogen, an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

K¹ and K² (hereinafter referred to as "K") can be the same or different. K is independently selected from divalent (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups, (vi) heterosubstituted derivatives of said groups (i) to (v), and (vii) hydrocarbyl-substituted heteroatom groups. Examples of suitable divalent groups K are -CH₂-, -CH₂CH₂-, -CH₂ CH₂CH₂-, 1,2- phenylene, fr<ms- 1,2-cyclopentane, frαrø-l^-cyclohexane, 2,3-butane, l,l'-biphenyl, 1,1'- binaphthyl, and -Si(Me)₂-. It is preferred that K is an aliphatic or aromatic hydrocarbon group. More preferably the divalent group K is -CH₂-.

D¹ and D² can be the same or different donor groups, for example oxygen, sulfur, an amine, an imine or a phosphine. Preferably D¹ and D² are selected from oxygen, sulfur, an amine of formula -N(R¹²)- or a phosphine of formula -P(R¹³)- wherein R¹² and R¹³ are hydrogen or (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon^ (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups, (vi) heterosubstituted derivatives of said groups (i) to (v), (vii) hydrocarbyl-substituted heteroatom groups and (viii) further imidazole-containing groups. Alternatively R¹² or R¹³ may be removed, for example by deprotonation when they are hydrogen, to give a formally monoanionic fragment; or if both R¹² or R¹³ are removed they provide a formally dianionic fragment. More preferably D² is an amine of formula -N(R¹²)- as defined above. R¹² is preferably hydrogen, an aliphatic hydrocarbon, an aromatic hydrocarbon or a further imidazole containing group. Preferably D² is an imidazole-containing group.

M is vanadium or a mixture of vanadium and a metal selected from Groups 3 to 11 of the periodic table, preferably from Groups 3 to 7, more preferably selected from Sc₃ Ti, Zr, Hf, Nb, Ta, Cr, Mo, W, Mn and most preferably Cr, Ti, Zr and Hf

The anionic group X can be, for example, a halide, preferably chloride or bromide; or a hydrocarbyl group, for example, methyl, benzyl or phenyl; a carboxylate, for example, acetate or an acetylacetonate; an oxide; an amide, for example diethyl amide; an alkoxide, for example, methoxide, ethoxide or phenoxide; or a hydroxyl. Alternatively, X can be a non-coordinating or weakly-coordinating anion, for example, tetrafluoroborate, a fluorinated aryl borate or a triflate. The anionic groups X may be the same or different and may independently be monoanionic, dianionic or trianionic.

The neutral donor group L can be, for example, a solvate molecule, for example diethyl ether or THF; an amine, for example, diethyl amine, trimethylamine or pyridine; a phosphine, for example trimethyl phosphine or triphenyl phosphine; or water; or an olefin or a neutral, conjugated or nonconjugated diene, optionally substituted with one or more groups selected from hydrocarbyl or trimethylsilyl groups, said group having up to 40 carbon atoms and forming a pi-complex with M. When L is a diene ligand, it can be, for example s-trans-η⁴-l,4-diphenyl-l,3-butadiene; s-trans-η⁴-3-methyl-l,3-pentadiene; s- trans-η⁴-l,4-dibenzyl-l,3-butadiene; s-trans-η⁴-2,4-hexadiene; s-trans-η⁴-l,3-pentadiene; s- trans-η⁴- 1 ,4-ditolyl- 1 ,3-butadiene; s-trans-η⁴- 1 ,4-bis(trimethylsilyl)- 1 ,3-butadiene; s-trans- η⁴- 1 ,4-diphenyl- 1 ,3 -butadiene; s-cis-η⁴-3 -methyl- 1 ,3 -pentadiene; s-cis-η⁴- 1 ,4-dibenzyl- 1,3- butadiene; s-cis-η⁴-2,4-hexadiene; s-cis-η⁴-l,3-pentadiene; s-cis-η⁴-l,4-ditolyl-l,3- butadiene; or s-cis-η⁴-l,4-bis(trimethylsilyl)-l,3-butadiene, said s-cis isomers forming a .pi.-bound diene complex; The value of y depends on the formal charge on each group Z and D, the charge on the anionic group X and the oxidation state of the metal M. For example, if M is chromium in oxidation state +3, Z is a neutral group and both D groups are neutral, then y is 3 if X is a monoanionic group (eg. chloride); if M is chromium in oxidation state +3, the Z group is neutral, one D group is monoanionic and the other D is neutral, then y is 2 if all X groups are monoanionic groups (e.g. chloride).

Preferred vanadium complexes which are covalently bonded to a support material in accordance with the present invention are selected from the following formulae:

R²⁰ to R²² are independently hydrogen or a monovalent (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups, (vi) heterosubstituted derivatives of said groups (i) to (v), and (vii) hydrocarbyl-substituted heteroatom groups.

Any one or more of the hydrogen atoms in the above formulae can be substituted by a functional group capable of reaction with a complimentary group on the support material to form a covalent linkage thereto. Examples of complexes that will react to form a covalent bond with supports having, for example, surface hydroxyl groups are

In the present invention the novel supported transition metal complexes can be catalytically active alone, or may require the use of an activator to render them sufficiently active for use in commercial polymerisation processes.

Accordingly the present invention further provides a polymerisation catalyst comprising a supported transition metal complex catalyst comprising e) a vanadium complex comprising at least one atom selected from boron, nitrogen, oxygen, phosphorus, sulphur and selenium, covalently bonded to f) a particulate inorganic support material, and g) an activating quantity of an activator selected from organoaluminium and organoboron compounds.

The supported transition metal complexes are preferably selected from those comprising a complex of Formula A, C, D and E described above.

The optional activator (g) for the catalyst of the present invention is suitably selected from organoaluminium compounds and organoboron compounds or mixtures thereof. Examples of organoaluminium compounds include trialkyaluminium compounds, for example, trimethylaluminium, triethylaluminium, tributylaluminium, tri-n-octylaluminium, ethylaluminium dichloride, diethylaluminium chloride, tris(pentafluorophenyl)aluminium and alumoxanes. Alumoxanes are well known in the art as typically the oligomeric compounds which can be prepared by the controlled addition of water to an alkylaluminium compound, for example trimethylaluminium. Such compounds can be linear, cyclic or mixtures thereof. Commercially available alumoxanes are generally believed to be mixtures of linear, cyclic and cage compounds. The cyclic alumoxanes can be represented by the formula [R¹⁶A1O]_S and the linear alumoxanes by the formula R^I7(R¹⁸A1O)_S wherein s is a number from about 2 to 50, and wherein R¹⁶, R¹⁷, and R¹⁸ represent hydrocarbyl groups, preferably Cj to Ce alkyl groups, for example methyl, ethyl or butyl groups. Examples of suitable organoboron compounds are dimethylphenylammoniumtetra(phenyl)borate, trityltetra(phenyl)borate, triphenylboron, dimethylphenylammonium tetra(pentafluorophenyl)borate, sodium tetrakistCbis-S^-trifluorpmethyOphenyyborate^COEt^tCbis-S^- trifluoromethyl)phenyl]borate, trityltetra(pentafluorophenyl)borate and tris(pentafluoroρhenyl) boron. Mixtures of organoaluminium compounds and organoboron compounds may be used.

In the preparation of the catalysts of the present invention the quantity of activating compound selected from organoaluminium compounds and organoboron compounds to be employed is easily determined by simple testing, for example, by the preparation of small test samples which can be used to polymerise small quantities of the monomer(s) and thus to determine the activity of the produced catalyst. It is generally found that the quantity employed is sufficient to provide 0.1 to 20,000 atoms, preferably 1 to 2000 atoms of aluminium or boron per atom of M present in the compound of Formula E. Mixtures of different activating compounds may be used. EP1238989 discloses the use of activators (Lewis acids), which also function as support materials, selected from

(b-1) ionic-bonding compounds having a CdCl₂ type or a CdI₂ type of layered crystal structure;

(b-2) clays, clay minerals, or ion-exchange layered compounds; (b-3) heteropoly-compounds; and

(b-4) halogenated lanthanoid compounds. Combined activator/support materials of this type can be used as the support in the present invention provided they are capable of reacting with the defined precursor transition metal complex to form the desired supported transition metal complex. The Lewis acid activators disclosed in EP1238989 can also be used in the present invention as the activator per se. Such Lewis acids are those compounds which capable of receiving at least one electron pair and is capable of forming an ion pair by reaction with the transition metal complex. The Lewis acid includes the afore-mentioned (b-1) ionic-bonding compounds having a layered crystal structure of a CdCl₂ type or CdI₂ type (b-2) clay . clay minerals, or ion- exchange layered compounds, (b-3) heteropoly compounds, and (b-4) halogenated lanthanoid compounds. The Lewis acid further includes SiO₂, Al₂O₃, natural and synthetic zeolites which have Lewis acid points formed by heating or a like treatment, and complexes and mixtures thereof. Combined activator/support materials of the type described on pp 124 - 129 of EP1238989 can suitably be used as the support material in the present invention, provided that such support can form a covalent bond with the transition metal complex precursor.

For example, the support can be a catalyst-activating support which is a solid particulate substance, insoluble in hydrocarbons, comprising at least magnesium and aluminium atoms and hydrocarbyloxy groups containing 1 to 20 carbons atoms, the molar ratio of Mg/Al being in the range 1.0 to 300 and the molar ratio of hydrocarbyloxy groups to aluminium atoms being in the range 0.05 to 2.0, the average particle size of the support being in the range 3 to 80 micrometres (μm). Under these circumstances the support preferably contains a Mg/Al ratio in the range 40 to 150 and has a molar ratio of hydrocarbyloxy to Al in the range 0.2 to 2.0. Such a material is preferably prepared by at least partially dissolving a magnesium halide, preferably magnesium dichloride, in an alcohol containing 1 to 20 carbons atoms and contacting the product with an organoaluminium compound having the formula AlR_nX_3-H wherein X is halogen or hydrogen and n is 1 to 3. Supports of this type are disclosed in WO 2004/037870 and for details of their preparation this disclosure provides useful information. Examples of organoaluminium compounds that can be employed to make catalyst-activating hydrocarbon-insoluble support are R3AI, R₂AlX and RAlX₂ wherein R is preferably Cj to C₂₀ hydrocarbyl, and X is chlorine or bromine, preferably chlorine. R is preferably selected from methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, tert butyl, n-pentyl, n-hexyl, n- octyl and n-decyl. Examples of alcohols that can be employed to make the catalyst- activating hydrocarbon-insoluble support are R¹OH wherein R¹ is aliphatic, alicyclic or aralkyl, for example, methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, tert butyl, n- pentyl, n-hexyl, n-octyl, n-decyl, cyclohexyl, ethylcyclohexyl and benzyl. The magnesium halide is preferably dissolved completely in the alcohol, heating or refluxing the mixture if necessary. Any undissolved magnesium halide is preferably separated before reacting the solution with the organoaluminium compound. Reacting the solution with the organoaluminium compound using quantities having the afore-recited Mg/Al ratios produces a solid having the desired chemical characteristics. The particle size of the product can be adjusted if desired by conventional methods, for examples, milling, sieving, pressing and the like. The catalyst-activating hydrocarbon-insoluble support and its preparation are suitably protected to exclude air and moisture. Preferably the preparation and storage are in an inert gas atmosphere. US Patent 6399535 discloses a coordinating catalyst system capable of polymerizing olefins comprising:

(I) as a pre-catalyst, at least one non-metallocene, non-constrained geometry, bidentate ligand containing transition metal compound or tridentate ligand containing transition metal compound capable of (A) being activated upon contact with the catalyst support- activator agglomerate of (H) or (B) being converted, upon contact with an organometallic compound, to an intermediate capable of being activated upon contact with the catalyst support-activator agglomerate of (IT), wherein the transition metal is at least one member selected from Groups 3 to 10 of the Periodic table; in intimate contact with

(II) catalyst support-activator agglomerate comprising a composite of (A) at least one inorganic oxide component selected from SiO₂, Al₂O₃, MgO, AlPO₄, TiO₂, ZrO₂, and

Cr₂O₃ and (B) at least one ion containing layered material having interspaces between the layers and sufficient Lewis acidity, when present within the catalyst support-activator agglomerate, to activate the pre-catalyst when the pre-catalyst is in contact with the catalyst support-activator agglomerate, said layered material having a cationic component and an anionic component, wherein said cationic component is present within the interspaces of the layered material, said layered material being intimately associated with said inorganic oxide component within the agglomerate in an amount sufficient to improve the activity of the coordinating catalyst system for polymerizing ethylene monomer, expressed as Kg of polyethylene per gram of catalyst system per hour, relative to the activity of a ^• corresponding catalyst system employing the same pre-catalyst but in the absence of either Component A or B of the catalyst support-activator agglomerate; wherein the amounts of the pre-catalyst and catalyst support-activator agglomerate which are in intimate contact are sufficient to provide a ratio of micromoles of pre-catalyst to grams of catalyst support- activator agglomerate of from about 5:1 to about 500:1. The layered material can be, for example, a smectite clay. The support material employed in the present invention can be a catalyst support-activator agglomerate as described in US 6399535 if desired provided that the support is capable of forming a covalent bond with the transition metal complex precursor.

In addition to the activator compound, it can be advantageous to employ catalytic quantities of certain halogenated compounds that are capable of promoting catalyst activity. Promotors of this type are especially useful in the case that the transition metal in the complex is vanadium. US Patent.5191042 discloses that certain vanadium-based catalysts activated with organoaluminium compounds can be promoted using a variety of halogenated organic compounds, for example, carbon tetrachloride, hexachloroethylene, benzylbromide, benzylchloride and 2,3- or 1,3-dichloropropylene. Other examples of halogenated organic compounds that can be used in this manner are ethyl trichloroacetate, chloroform (CHCI₃) and n-butylchloride. US Patent.5191042 also refers to the disclosure of Cooper (T. A Cooper, Journ. Am. Chem. Soc, 4158 (1973), which defines in Table 1 an organic halide activity index based on the ability of the halide to oxidize certain vanadium compounds under standard conditions. For example, carbon tetrachloride is assigned a reactivity of 1 in tetrahydrofuran at 20 ⁰C, and other listed halogenated organic compounds have reactivities of from about 0.02 to greater than 200 relative to carbon tetrachloride. When it is desired to use a halogenated promotor, it is preferred to use those having a Cooper Index ranging from about 0.01 up to about 30. The use of such promoters, especially in combination with vanadium-based catalysts is generally well known in the art, and for details of use of the such promoters reference may be made to US Patent.5191042 and to other prior art in this field. In the present invention it is possible to employ any halogenated organic compound as a promoter, but the compounds mentioned above are preferred.

The catalysts of the present invention can if desired comprise the defined vanadium complex together with one or more similar or different complexes of one or more other transition metal compounds.

In addition to said one or more defined transition metal compounds, the catalysts of the present invention can also include one or more other catalysts for polymerising 1 -olefins. Preferably such catalysts are other types of transition metal compounds or catalysts, for example, transition metal compounds of the type used in conventional Ziegler-Natta catalyst systems, metallocene-based catalysts, or heat activated supported chromium oxide catalysts (eg Phillips-type catalyst). The catalysts of the present invention may also used in conjunction with other catalysts producing only 1 -olefins, either inside or outside the polymerisation reactor, and in this way make copolymers of ethylene or propylene and these 1 -olefins. Suitable catalysts for producing 1 -olefins may produce only 1-butene, only 1-hexene or a distribution (for example, a Schulz-Flory distribution) of 1- olefins.

The catalyst or catalysts of the present invention can be employed, if desired, using processes analogous to those disclosed in WO02/46246 and US6605675. For example, a . catalyst component slurry and a catalyst component solution can be combined before or during introduction into the polymerisation reactor. The properties of polymers produced using such methods can be advantageously controlled thereby. The catalysts of the present invention can also be employed in the process disclosed in US6610799. In this process, mixtures of two or more supported catalysts can be utilised containing differing amounts of catalyst components wherein the concentrations of the individual catalyst components can be independently controlled within the polymerisation reactor.

The present invention further provides a process for the polymerisation and copolymerisation of 1 -olefins, cycloolefins or dienes, comprising contacting the monomer under polymerisation conditions with the polymerisation catalyst of the present invention. Suitable monomers for use in making homopolymers using the polymerisation process of the present invention are, for example, ethylene, propylene, butene, hexene, styrene or conjugated or non-conjugated dienes. Preferred monomers are ethylene and propylene.

Suitable monomers for use in making copolymers using the polymerisation process of the present invention are two or more of ethylene, propylene, 1-butene, 1-hexene, 4- methylpentene-1, 1-octene, norbornene, substituted norbornenes, dienes, eg butadiene, ethylidene norbornene, methyl methacrylate, methyl acrylate, butyl acrylate, acrylonitrile, vinyl acetate, vinyl chloride, and styrene.

A particularly preferred process in accordance with the present invention is the copolymerisation of ethylene and or propylene with comonomers selected from 1 -olefins, acrylic acid esters, vinyl esters and vinyl aromatic compounds. Examples of suitable comonomers are 1-butene, 1-hexene, 4-methylpentene-l, methyl methacrylate, methyl acrylate, butyl acrylate, acrylonitrile, vinyl acetate, and styrene.

Preferred polymerisation processes are the homopolymerisation of ethylene or the homopolymerisation of propylene or copolymerisation of ethylene with one or more of propylene, butene, hexene-1 and 4-methylpentene-l or copolymerisation of propylene with one or more of ethylene or butene.

The polymerisation conditions can be, for example, bulk phase, solution phase, slurry phase or gas phase. If desired, the catalyst can be used to polymerise ethylene under high pressure/high temperature process conditions wherein the polymeric material forms as a melt in supercritical ethylene. Preferably the polymerisation is conducted under gas phase fluidised or stirred bed conditions.

Slurry phase polymerisation conditions or gas phase polymerisation conditions are particularly useful for the production of high-density grades of polyethylene. In these processes the polymerisation conditions can be batch, continuous or semi-continuous. In the slurry phase polymerisation process the solid particles of supported catalyst, are fed to a polymerisation zone either as dry powder or as a slurry in the polymerisation diluent. Preferably the particles are fed to a polymerisation zone as a suspension in the polymerisation diluent. The polymerisation zone can be, for example, an autoclave or similar reaction vessel, or a continuous loop reactor, e.g. of the type well know in the manufacture of polyethylene by the Phillips Process. When the polymerisation process of the present invention is carried out under slurry conditions the polymerisation is preferably carried out at a temperature above 0⁰C, most preferably above 15°C. The polymerisation temperature is preferably maintained below the temperature at which the polymer commences to soften or sinter in the presence of the polymerisation diluent. If the temperature is allowed to go above the latter temperature, fouling of the reactor can occur. Adjustment of the polymerisation within these defined temperature ranges can provide a useful means of controlling the average molecular weight of the produced polymer. A further useful means of controlling the molecular weight is to conduct the polymerisation in the presence of hydrogen gas which acts as chain transfer agent. Generally, the higher the concentration of hydrogen employed, the lower the average molecular weight of the produced polymer.

The use of hydrogen gas as a means of controlling the average molecular weight of the polymer or copolymer applies generally to the polymerisation process of the present invention. For example, hydrogen can be used to reduce the average molecular weight of polymers or copolymers prepared using gas phase, slurry phase or solution phase polymerisation conditions. The quantity of hydrogen gas to be employed to give the desired average molecular weight can be determined by simple "trial and error" polymerisation tests.

Methods for operating gas phase polymerisation processes are well known in the art. Such methods generally involve agitating (e.g. by stirring, vibrating or fluidising) a bed of catalyst, or a bed of the target polymer (i.e. polymer having the same or similar physical properties to that which it is desired to make in the polymerisation process) containing a catalyst, and feeding thereto a stream of monomer at least partially in the . gaseous phase, under conditions such that at least part of the monomer polymerises in contact with the catalyst in the bed. The bed is generally cooled by the addition of cool gas (eg recycled gaseous monomer) and/or volatile liquid (eg a volatile inert hydrocarbon, or gaseous monomer which has been condensed to form a liquid). The polymer produced in, and isolated from, gas phase processes forms directly a solid in the polymerisation zone and is free from, or substantially free from liquid. As is well known to those skilled in the art, if any liquid is allowed to enter the polymerisation zone of a gas phase polymerisation process the quantity of liquid is small in relation to the quantity of polymer present in the polymerisation zone. This is in contrast to "solution phase" processes wherein the polymer is formed dissolved in a solvent, and "slurry phase" processes wherein the polymer forms as a suspension in a liquid diluent.

The gas phase process can be operated under batch, semi-batch, or so-called "continuous" conditions. It is preferred to operate under conditions such that monomer is continuously recycled to an agitated polymerisation zone containing polymerisation catalyst, make-up monomer being provided to replace polymerised monomer, and continuously or intermittently withdrawing produced polymer from the polymerisation zone at a rate comparable to the rate of formation of the polymer, fresh catalyst being added to the polymerisation zone to replace the catalyst withdrawn form the polymerisation zone with the produced polymer.

A problem that can occur in the gas and slurry phase polymerisation of olefins is that of fouling of the reactor walls, any stirrer that may be present and spalling or agglomeration of the polymer due, for example, to the presence of static electricity. The problem can be reduced or eliminated by judicious use of suitable antistatic agents. One example of a family of antistatic agents suitable for use in the polymerisation of olefins are commercially available under the trade name "STADIS".

When using the catalysts of the present invention under gas phase polymerisation conditions, the supported transition metal complex can be introduced into the reactor as a dry powder or as a slurry in a suitable inert volatile solvent, preferably a C₃ to C₆ hydrocarbon, for example n-hexane. The activator may be introduced separately from, or together with the complex. The activator can be fed, for example, as vapour, or liquid or solid. Preferably it is fed either as part of the pre-activated catalyst system, or as a spray in a suitable inert solvent, for example a volatile hydrocarbon. Alternatively, the components for making the supported transition metal complex can be fed separately to the reactor so they react therein to from the complex. For example the complex precursor can be dissolved in a suitable volatile hydrocarbon solvent and introduced into a gas fluidised bed simultaneously with or separately from the support material. The support material can be in the form of a slurry in volatile hydrocarbon, or fed as dry powder. The preactivated catalyst or the supported transition metal complex can be fed to the reactor as a dry powder or as a slurry in a suitable volatile hydrocarbon diluent. References in the foregoing paragraph to volatile hydrocarbons include any hydrocarbon or other suitable volatile inert diluent. For example, ethane, propane, n-butane, isobutene, and one or more isomers of pentane, hexane, heptane.

The catalyst of the present invention can be used in conventional commercial polymerisation facilities and its use can be sandwiched between production runs using other commercial catalyst systems of the supported or unsupported type, eg, using Ziegler Natta catalysts, metallocene catalysts, heat activated chromium oxide catalysts and late transition metal catalyst systems. Transitioning between catalyst systems of these types has been extensively described in the prior art and reference may be made to the prior art methods for analogously suitable methods readily adaptable to use of the catalyst of the present invention. For example, see EP 751965, US 5442019, US5672665, US5747612, US 5753786, EP 830393, US 5672666, EPl 171486, EP885247, EPl 182216, US6284849. US2004/0127655, WO04/060938, US2004/0138391, WO, 04/060921, WO04/060922, WO04/060929, WO04/060930, and WO04/060931.

The present invention also provides a process for the oligomerisation and cooligomerisation of 1 -olefins, comprising contacting the monomeric olefin Under oligomerisation conditions with the catalyst of the present invention.

Suitable monomers for use in making homooligomers using the oligomerisation process of the of the present invention are, for example, ethylene, propylene, butene, hexene, and styrene. The preferred monomer is ethylene. Suitable monomers for use in making co-oligomers using the oligomerisation process of the present invention are ethylene, propylene, 1 -butene, 1 -hexene, 1-octene, 1- decene, 1-dodecene and further 1 -olefins of the series C(n)H(2n) where n is an integer. There exist a number of options for the oligomerisation reactor including batch, semi- batch, and continuous operation. The oligomerisation and co-oligomerisation reactions of the present invention can be performed under a range of process conditions that are readily apparent to those skilled in the art: as a homogeneous liquid phase reaction in the presence or absence of an inert hydrocarbon diluent such as toluene or heptanes; as a two-phase liquid/liquid reaction; as a slurry process where the catalyst is in a form that displays little or no solubility; as a bulk process in which essentially neat reactant and/or product olefins serve as the dominant medium; as a gas-phase process in which at least a portion of the reactant or product olefm(s) are transported to or from a supported form of the catalyst via the gaseous state. Evaporative cooling from one or more monomers or inert volatile liquids is but one method that can be employed to effect the removal of heat from the reaction. The (co-)oligomerisation reactions may be performed in the known types of gas-phase reactors, such as circulating bed, vertically or horizontally stirred-bed, fixed-bed, or fluidised-bed reactors, liquid-phase reactors, such as plug-flow, continuously stirred tank, or loop reactors, or combinations thereof. A wide range of methods for effecting product, reactant, and catalyst separation and/or purification are known to those skilled in the art and may be employed: distillation, filtration, liquid-liquid separation, slurry settling, extraction, etc. One or more of these methods may be performed separately from the (co-)oligomerisation reaction or it may be advantageous to integrate at least some with a (co-)oligomerisation reaction; a non-limiting example of this would be a process employing catalytic (or reactive) distillation. Also advantageous may be a process which includes more than one reactor, a catalyst kill system between reactors or after the final reactor, or an integrated reactor/separator/purifier. While all catalyst components, reactants, inerts, and products could be employed in the present invention on a once- through basis, it is often economically advantageous to recycle one or more of these materials; in the case of the catalyst system, this might require reconstituting one or more of the catalysts components to achieve the active catalyst system. It is within the scope of this invention that a (co)oligomerisation product might also serve as a reactant (e.g. 1- hexene, produced via the oligomerisation of ethylene, might be converted to decene products via a subsequent co-oligomerisation reaction with two further ethylene units). The catalyst systems of the present invention can present a variety of advantages over the prior art systems. In general the catalysts are easy to synthesise, have high activity and good catalyst life when employed under conventional industrial polymerisation conditions. Example 1 1.1 Synthesis of N,N-bis(lH-benzimidazoI-2-yImethyI)-N-methylamine (L-I)

190⁰C

A mixture of 4.00 g (27.2 mmol) N-methyliminodiacetic acid and 5.99 g (54.4 mmol) o-phenylene diamine in 30 ml ethylene glycol was stirred at 19O⁰C for 4 hours. The water produced during was distilled off continuously. At the end of the reaction, the reaction mixture was allowed to cool down to room temperature and then poured in 150 ml water. The obtained slurry was triturated for 30 min, filtered, washed with water (3 x 30 ml) and dried at 6O⁰C under reduced pressure for 48 hours. Yield 6.88 g (87.0%).

1.2 Synthesis of 2-(2-{[(lH-benzimidazol-2-ylmethyl)(methyl)amino]methyI}-lH- benzimidazol-l-yl)hexyloxydimethyl-terf-butylsilane (L-4)

A mixture of 1.0 g (3.4 mmol) N,N-bis(lH-benzimidazol-2-ylmethyl)-N-methylamine and 0.082 g (3.4 mmol) NaH in 20 ml THF was stirred until obtaining a clear solution. 6- Bromohexyloxydimethyl-tert-butylsilane (1.0 g, 3.4 mmol) was added and the reaction mixture stirred for 24 hours. The volatiles were evaporated under vacuum and the pale yellow residue extracted with DCM (3 x 30 ml). The solvent was evaporated and the residue dried under reduced pressure for 12 hours. Yield - 0.3 g (17.5 %).

1.3 Synthesis of N,N,N-[2-(2-{[(l£-^r-benzimidazoI-2-ylmethyl)(methyl)amino]methyl}- lH-benzimidazol-l-yl)hexyloxydimethyl-tert-butylsilane]di-propoxyoxovanadium(V)

(V-4)

A solution of 0.1 Ig (0.21 mmol) 2-(2-{[(lH-benzimidazol-2-ylmethyl)(methyl)- amino]methyl}-lH-benzimidazol-l-yl)hexyloxydimethyl-tert-butylsilane in 10 ml TΗF cooled to -78° C was mixed with 0.05 ml (0.21 mmol) tris(propoxy)oxovanadium(V), allowed to warm up to room temperature and stirred for 30 min. The reaction mixture was concentrated to about 1 ml and 50 ml heptane were added. The formed precipitate was filtered, washed with heptane (2 x 5 ml) and dried under reduced pressure. Yield - 0.1 g (67%).

1.4 Preparation of Silica supported catalyst (SV-4)

A solution of 2.1 mg (3 μmol) V-4 in 10 ml toluene was added to 0.1 g silica 948 ( 2h at 250⁰C). The resulting slurry was stirred at reflux for Ih, mixed with 1 ml 2M TMA and stirred for another 5 min at reflux.

1.5 Ethylene polymerization using catalyst SV-4

The supported catalyst SV-4 described above was mixed with 200 ml toluene and then 3 ml IM dimethylaluminium chloride in hexanes and 2.2 ml 0.4M ethyl trichloroacetate in toluene were added. The polymerisation was carried out in a 450 ml magnetically stirred Schlenk tube at 1 bar ethylene pressure and 6O⁰C for 15 min. Polymer yield - 2.1 g. Catalyst activity - 2800 g mmorVbar^"1.

Example 2

2.1 Synthesis of N,N-bis(lΗ-benzimidazol-2-ylmethyl)amine (L-2)

19O⁰C

A mixture of 3.62 g (27.2 mmol) N-imlnodiacetic acid and 4.40 g (54.4 mmol) o-phenylene diamine in 30 ml ethylene glycol was stirred at 19O⁰C for 4 hours. The water produced during was distilled off continuously. At the end of the reaction, the reaction mixture was allowed to cool down to room temperature and then poured in 150 ml water. The obtained slurry was triturated for 30 min, filtered, washed with water (3 x 30 ml) and dried at 60⁰C under reduced pressure for 48 hours. Yield 5.28 g (70.0%).

2.2 Synthesis of (Bis{[10-carboxydecyI)-lH-benzimidazol-2-yl]methyl}amino)-ll- undecanoic acid (L-3)

2M HCI

A suspension of 1.Og (3.6 mmol) N,N-bis(lH-benzimidazol-2-ylmethyl)amine, 1.Og (7.2 mmol) anhydrous potassium carbonate and 2.9 g (10.8 mmol) 11-bromoundecanoic acid in 20 ml dry dimethylformamide was stirred at room temperature for 72 hours. The reaction mixture was poured in a beaker containing 200 ml water, stirred for 30 min and then carefully neutralized with 2M HCl. The precipitate was washed with water (4 x 20 ml) and dried under reduced pressure for 24 hours. Yield 2. Lg (74.0 %).

2.3 Synthesis of NjNjN-^islllO-carboxydecyO-lH-benzimidazoI^-yllmethyl}-!!- carboxydecyIamiήe)vanadium(IH) chloride (V-3)

A solution of 0.5g (0.6 mmol) (Bis{[10-carboxydecyl)-lH-benzimidazol-2- yl]methyl} amino)- 11-undecanoic acid and 0.22 g (0.6 mmol) VC1₃.3THF in 20 ml THF was stirred for 4 hours. The formed pale green precipitate was filtered, washed with THF (3 x 10 ml) and dried under vacuum. Yield 0.5 g (85%).

2.4 Preparation of Silica supported catalyst (SV-3) ^l

A solution of 1 mg (1 μmol) V-3 in 10 ml toluene was mixed with 0.02 ml 2M TMA in toluene. The reaction mixture was stirred at 7O⁰C for 30 min and then added to 0.1 g silica 948 ( 2h at 25O⁰C). The resulting slurry was stirred at 70⁰C for Ih, mixed with 1 ml 2M TMA and stirred for another 30 min at 7O⁰C.

2.5 Ethylene polymerization using supported catalyst SV3 The supported catalyst SV-3 described in 2.4 above, was mixed with 200 ml toluene and then 1 ml IM dimethylaluminium chloride in hexanes and 19 ml 25 mM ethyl trichloroacetate in toluene were added. The polymerisation was carried out in a 450 ml magnetically stirred Schlenk tube at 1 bar ethylene pressure and 6O⁰C for 40 min. Polymer yield 2.7 g. Activity- 4050 g mmol^'Vbar^"1.

In Example 2, during the activation of the catalyst, the carboxylic groups on the vanadium complex are reacted with TMA thus forming an active catalyst containing -(CH₂)_!o-C(0)- 0-AlMe₂ groups. When this is added to the silica, covalent bonds of the type:

(Silica)-0-Al(Me)-0-(0)C-(CH₂)io-(complex residue) or

(Silica)-O-Al(-O-)-O(O)C-(CH₂)₁₀-(complex residue) . thus anchoring the complex residue to the silica.

Claims

2005/00422!38Claims

1. A supported transition metal complex comprising

(a) a vanadium metal complex comprising at least one atom selected from boron, nitrogen, oxygen, phosphorus, sulphur and selenium, covalently bonded to

(b) a particulate inorganic support material.

2. A complex as claimed in Claim 1 wherein the transition metal in the complex is vanadium alone.

3. A complex as claimed in Claim 1 or 2 wherein the transition metal complex contains at least two atoms selected from boron, nitrogen, oxygen, phosphorus, sulphur and selenium.

4. A complex as claimed in Claim 1, 2 or 3 wherein the complex contains two or more nitrogen atoms; or a nitrogen and an oxygen atom; or a phosphorus and an oxygen atom.

5. A complex as claimed in any one of the preceding Claims wherein the support material is selected from silica, alumina, zirconia, magnesia, calcium carbonate, natural or synthetic clays, talc, and magnesium chloride.

6. A process for preparing a supported transition metal complex comprising reacting together c) a vanadium complex precursor comprising at least one atom selected from boron, nitrogen, oxygen, phosphorus, sulphur and selenium, and having at least one functional group capable of reacting with d) a functional group on a solid particulate support material to form at least one covalent.

7. A process as claimed in Claim 6 wherein the functional group on the transition metal complex precursor capable of reacting with the support material is selected from hydroxyl, acetal, ketal, tertiaryalkoxyalkyl, benzoyloxyalkyl, monothioacetal, monothioketal and a reactive silicon containing group.

8. A process as claimed in Claim 7 wherein the reactive silicon-containing group has the formula -Si(OR)_n (X)m (R)p wherein n, m and p are each 0, 1, 2 or 3 provided that n+m+p = 1 to 3, R is hydrocarbyl and X is selected from Cl and F. T/GB2005/004221

39

9. A process as claimed in any one of Claims 6 to 8 wherein the transition metal compound precursor the general formula of Formula A below:

FG

Ligand A ] M(X)_y(L)_z Formula A n

wherein "Ligand A" is a mono-, di- , tri- or tetradentate organic ligand having one or more functional groups "FG" capable of reaction with a reactive group on an inorganic support to form a covalent bond, M comprises vanadium, X is an anionic group, L is a ligand or neutral donor group; n is 1 , 2 ,3 or 4, y and z are independently zero or integers such that the number of Ligand, X and L groups satisfy the valency and oxidation state of the metal M.

10. A process as claimed in Claim 9 wherein "Ligand A" in Formula A is represented by the bidentate group having Formula B

Formula B

wherein the monovalent groups R¹ and R² are independently selected from -R^a, -OR^b, -NR^cR^d, and-NHR^e: the monovalent groups R^a, R^b, R^c, R^d, and R^e, and the divalent group R³ are independently selected from (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups and (vi) heterosubstituted derivatives of said groups (i) to (v);

M is vanadium, or vanadium and a metal from Group 3 to 11 of the Periodic Table or a lanthanide metal; E is phosphorus or arsenic; X is an anionic group, L is a neutral donor group; n is 1 or 2, y and z are independently zero or integers such that the number of X and L groups satisfy the valency and oxidation state of the metal M and "FG" is a substituent functional group pendant from at least one of the groups R¹, R² and R³.

11. A process as claimed in Claim 9 wherein the transition metal complex precursor has the Formula C

Formula C

wherein the monovalent groups R¹ and R² are independently selected from -R^a, -OR^b, -NR^cR^d, and-NHR^e: the monovalent groups R^a, R^b, R^c, R^d, and R^e, and the divalent group R³ are independently selected from (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups and (vi) heterosubstituted derivatives of said groups (i) to (v); M is vanadium, or vanadium and a metal from Group 3 to 11 of the Periodic Table or a lanthanide metal; E is phosphorus or arsenic; X is an anionic group, L is a neutral donor group; n is 1 or 2, y and z are independently zero or integers such that the number of X and L groups satisfy the valency and oxidation state of the metal M and "FG" is a substituent functional group pendant from at least one of the groups R¹, R² and R³.

12. A process as claimed in Claim 6 wherein the complex precursor is selected from those having the formulae

wherein the at least one functional group on the complex is pendant from at least one of the phenyl and / or ortho-phenylene groups, and / or from the C₂ group connecting the two phosphorus atoms.

13. A process as claimed in Claim 9 wherein "Ligand A" in Formula A is represented by the tridentate group having Formula E*

Formula E*

wherein Z comprises a five-membered heterocyclic group, the five membered heterocyclic group containing at least one carbon atom, at least one nitrogen atom and at least one other hetero atom selected from nitrogen, sulphur and oxygen, the remaining atoms in said ring being selected from nitrogen and carbon; M is solely vanadium or a mixture of vanadium and a metal from Group 3 to 11 of the Periodic Table or a lanthanide metal; K¹ and K² are divalent groups independently selected from (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups and (vi) heterosubstituted derivatives of said groups (i) to (v); D¹ and D² are donor atoms or groups; X is an anionic group, L is a neutral donor group; n = m = zero or 1; y and z are independently zero or integers such that the number of X and L groups satisfy the valency and oxidation state of the metal M and the substituent functional group "FG" is pendant from at least one of the groups D¹, D², K¹, K² and Z.

14. A process as claimed in Claim 9 wherein the transition metal complex precursor has the Formula E

wherein Z comprises a five-membered heterocyclic group, the five membered heterocyclic group containing at least one carbon atom, at least one nitrogen atom and at least one other hetero atom selected from nitrogen, sulphur and oxygen, the remaining atoms in said ring being selected from nitrogen and carbon; M is solely vanadium or a mixture of vanadium and metal from Group 3 to 11 of the Periodic Table or a lanthanide metal; K¹ and K² are divalent groups independently selected from (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups and (vi) heterosubstituted derivatives of said groups (i) to (v); D¹ and D² are donor atoms or groups; X is an anionic group, L is a neutral donor group; n = m = zero or 1 ; y and z are independently zero or integers such that the number of X and L groups satisfy the valency and oxidation state of the metal M, and the substituent functional group "FG" is pendant from at least one of the groups D¹, D², K¹, K² and Z.

15. A process as claimed in Claim 14 wherein Z is an imidazole-containing group.

16. A process as claimed in Claim 15 wherein the imidazole-containing group Z is a group of Formula I, II or HI wherein at least one of the substituents R¹ to R¹¹ has a pendant functional group "FG".

Formula I Formula II Formula III

R¹ to R¹¹ are independently hydrogen or a monovalent (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups, (vi) heterosubstituted derivatives of said groups (i) to (v), and (vii) hydrocarbyl-substituted heteroatom groups, the valence bond oh the single carbon atom between the two nitrogen atoms of Formulae I, II and HI provides at least one of the links of K into the rest of Formula E, the other link or links being provided by at least one of the nitrogen atoms in the imidazole-containing group.

17. A polymerisation catalyst comprising a supported transition metal complex catalyst comprising e) a vanadium complex comprising at least one atom selected from boron, nitrogen, oxygen, phosphorus, sulphur and selenium, covalently bonded to f) a particulate inorganic support material, and g) an activating quantity of an activator selected from organoaluminium and organoboron compounds.

18. A polymerisation catalyst comprising the supported transition metal complex claimed in any one of Claims 1 to 6 and an activating quantity of an activator selected from organoaluminium and organoboron compounds

19. A polymerisation catalyst comprising the supported transition metal complex prepared by the process claimed in any one of Claims 7 to 16 and an activating quantity of an activator selected from organoaluminium and organoboron compounds.

20. A polymerisation catalyst as claimed in anyone of Claims 17 to 19 wherein the activator is selected from trimethylaluminium, triethylaluminium, tributylaluminium, tri-n- octylaluminium, ethylaluminium dichloride, diethylaluminium chloride, tris(pentafluorophenyl)aluminium, an alumoxane, dimethylphenylammoniumtetra(phenyl)borate, trityltetra(phenyl)borate, triphenylboron, dimethylphenylammonium tetra(pentafluorophenyl)borate, sodium tetrakis[(bis-3,5-trifluoromethyl)phenyl]borate, H⁺(OEt₂)[CbIs-S₅S- trifluoromethyl)phenyl]borate, trityltetra(pentafluorophenyl)borate and tris(pentafluorophenyl) boron.

21. A polymerisation catalyst as claimed in any one of Claims 17 to 20 wherein in addition to the activator compound, a promoter is employed comprising a halogenated compound selected from carbon tetrachloride, hexachloroethylene, benzylbromide, benzylchloride and 2,3- or 1,3-dichloropropylene, ethyl trichloroacetate, chloroform and n- butylchloride.

22. A process for polymerisation and copolymerisation of 1-olefins, cycloolefins or dienes, comprising contacting the monomer under polymerisation conditions with the polymerisation catalyst claimed in any one of Claims 17 to 21

23. A process as claimed in Claim 22 wherein the the polymerisation is homopolymerisation of monomer selected from ethylene, propylene, butene, hexene, styrene, conjugated diene and non-conjugated diene

24. A process as claimed in Claim 22 wherein the polymerisation is copolymerisation of two or more monomers selected from ethylene, propylene, 1 -butene, 1 -hexene, 4- methylpentene-1, 1-octene, norbornene, substituted norbornenes, butadiene, ethylidene norbornene, methyl methacrylate, methyl acrylate, butyl acrylate, acrylonitrile, vinyl acetate, vinyl chloride, and styrene.

25. A process as claimed in Claim 22 wherein the polymerisation is copolymerisation of ethylene and/or propylene with comonomers selected from 1-olefins, acrylic acid esters, vinyl esters and vinyl aromatic compounds. 26 A process as claimed in Claim 25 wherein the comonomer is selected from 1- butene, 1 -hexene, 4-methylpentene-l, methyl methacrylate, methyl acrylate, butyl acrylate, acrylonitrile, vinyl acetate, and styrene.