A NEW TRANSITION METAL COMPLEX, ITS PREPARATION AS WELL AS A CATALYST SYSTEM COMPRISING BASED THEREUPON AND ITS USE FOR THE POLYMERIZATION OF OLEFINS

Abstract: The invention relates to new triaza transition metal complexes and their use as polymerization catalysts. They have the formula (1): LnMXm-n, wherein each L is independently a ligand which is multidentate by adjacent cooordinating atoms, M is the central atom which is a metal selected from Groups 4-8 of the Periodic Table of the Elements (IUPAC 1990), each X is independently a unidentate organic or halogen ligand, m is the coordination number or number of coordination sites on the central atom M, and n is the number of the ligands L which is an integer from 1 to m. At least one of the ligands L has formula (2), wherein each of R1-R6 is independently selected from hydrogen and organic groups having from 1 to 10 carbon atoms and the ligand L is coordinated to the central atom M by one to four of the three nitrogen atoms and/or the carbon atom of the ligand L according to formula (2).

Description: A new transition metal complex, its preparation as well as a catalyst system comprising based thereupon and its use for the polymerization of olefins The invention relates to a triaza transition metal complex having the formula (1) L n MX m . n (1) wherein each L is independently a multidentate ligand, M is the central atom which is a metal selected from Groups 4-8 of the Periodic Table of the Elements (IUPAC 1990), each X is independently a unidentate organic or halogen ligand, m is the coordination number or number of coordination sites on the central atom M, and n is the number of the ligands L which is an integer from 1 to m. The complex may also be ionic. The invention also relates to a process for the preparation of a transition metal complex of the above type. Further, the invention relates to another new complex, which can be used in the preparation of the above mentioned transition metal complex. Finally, the invention relates to a polymerization catalyst system comprising the above mentioned transition metal complex, and the use of such a catalyst system for the polymerization of ethylenically unsaturated compounds. In the above mentioned triaza transition metal complex of the invention, each of the ligands L and X can be connected by bivalent L-L, X-X or L-X bridges. Such bridges are e.g. al ylene bridges as well as silylene and other heteroatomic bridges. Aza transition metal complexes are disclosed e.g. in Chem. Ber. 129(1996)1087- 1091, Chem. Abstr. 127(1997)248532, DE 27 35 286, EP 82 415 and J. Am. Chem. Soc. 92(1970)5118-5126. They all relate to >C=N- groups coordinated to the central atom by a π-bond, or N-atoms coordinated to the central atom by a σ-bond. In the present invention, it was surprisingly found that aza complexes could be prepared, in which the ligand was bound to the central atom in a totally new way. The new triaza transition metal complexes could be used in the polymerization of olefins. With the above mentioned transition metal complex according to formula (1), it was found possible to prepare and use for polymerization complexes, in which at least one of the ligands L of the above formula (1) has the formula (2) wherein each of R Rβ is independently selected from hydrogen and organic groups having from 1 to 10 carbon atoms. This ligand is coordinated to the central atom M by one, two, three or four of the three nitrogen atoms and/or the carbon atom of the ligand L according to the formula (2). Note especially the fact that the carbon atom connecting the three nitrogen atoms is three-valent and thus gives rise to a carbanion or the like. In said ligand of formula (2), the groups RpRβ can be hydrogen or any organic group with or without heteroatoms. According to certain embodiments of the invention, RpRβ are independently selected from hydrogen, Cι-C 1 alkyls, CpC 12 alkenyls, C 6 -C 18 aryls and silyls such as tri- Cι-C 1 alkylsilyls. According to a preferred embodiment of the invention, adjacent groups selected from Ri-Rβ of the ligand may be interconnected to form rings. Thus some or all of the pairs: R t and R 2 , R 3 and t , and R 5 and R <5 may form ring structures. Most preferably, at least one of the pairs: R 2 and R 3 , R 4 and R 5 , and Rg and R t are interconnected to form a ring structure. These ring structures may be substituted further or fused with other rings. If the ring structures are substituted, typical substituents are C Cι 2 alkyls, Cι-Cι 2 alkenyls, C 6 -C 18 aryls and silyls. The ring structure may be fused with a further aliphatic or aromatic ring. The ring structures of the ligand may also contain other heteroatoms than the nitrogen atoms of formula (2). According to the most preferred embodiment of the invention, the groups of all of the pairs: R 2 and R 3 , R and R 5 , as well as Re and Ri of the above defined L ligand are interconnected to form bridge structures which are selected from 2 carbon and 3 carbon chains. Then, the ligands L of the claimed complex may e.g. have the following formulas: in which formulas any of the ring structures may independently from the other ring structures contain a π bond in any position. The most preferred ligands N are l,5,9-triazatricyclo[7.3.1.0] ' tridecanyl (1) and l,4,7-triazatricyclo[5.2.1.0 4 10 ] decanyl (2). Said ligand N is a tetradentate ligand and according to formulas (l)and (2) coordinated by four adjacent atoms to a transition metal M belonging to any of Groups 4 to 8 of the Periodic Table of the Elements (IUPAC 1990). Preferably, the transition metal M is selected from iron Fe, chromium Cr, titanium Ti and zirconium Zr. As was said initially, not necessary all of the multidentate ligands L of the complex of formula (1) have the general formula (2). Other ligands may be present, as well, as long as at least one of the L ligands fulfill the definition given in formula (2). Such other L ligands may e.g. be π-bonded alkenes and polyenes, as well as π- bonded charged aromatic rings such as the cyclobutadiene dianion and the cyclo- pentadienide ion (cyclopentadienyl anion). They are well-known as multidentate ligands for transition metal complexes. In addition to the ligand L of formula (2), which is a multidentate ligand by adjacent cooordinating atoms (3 N + 1 C), another type of ligand is also bound to the transition metal M, namely the unidentate organic or halogen ligand X. If X is an organic ligand, it may or may not contain a heteroatom. It may also form a bridge to another ligand X or to at least one of the ligands L, in which case it preferably is an amino bridge. Typical non-bridge organic ligands X are alkyls and alkylamido groups, preferably C C 3 alkyls such as methyl. It is preferable, if the ligand X is a halogen, most preferably chlorine Cl. In principle, the ligands L may alone saturate the central atom M coordinatively. However, it is preferable, if the complex also has an X ligand coordinated thereto. Most preferably, the number n of ligands L is selected from 1 and 2, whereby the number of X ligands exceeds 1. In the following, examples of preferred transition metal complexes according to the present invention is given. Any of the one, two, three or four atoms (one C and three N atoms) may be coordinated to the transition metal. The complex may be a l,5,9-triazatricyclo[7.3.1.0] ' tridecanyl chromium dichloride of the formula (3): a l,5,9-triazatricyclo[7.3.1.0] -5,'13 tridecanyl zirconium trichloride of the formula (4): a bis{ l,5,9-triazatricyclo[7.3.1.0] ' tridecanyl} zirconium dichloride of the formula (5): a l,4,7-triazatricyclo[5.2.1.0 vU ' O ] decanyl chromium dichloride of the formula (6): a l,4,7-triazatricyclo[5.2.1.0 -,4,'10 ] decanyl titanium trichloride of the formula (7): or a bis{ l,4,7-triazatricyclo[5.2.1.0 4 ' 10 ] decanyl} zirconium dichloride of the formula (8): Typical complex structures are l-5,9-triazatricyclo[7.3.1.0] " tridecanyl chromium trichloride l,5,9-triazatricyclo[7.3.1.0] tridecanyl iron trichloride l,5,9-triazatricyclo[7.3.1.0] 5 13 tridecanyl iron dichloride l,5,9-triazatricyclo[7.3.1.0] tridecanyl chromium dichloride l,5,9-triazatricyclo[7.3.1.0] 5 13 tridecanyl titanium trichloride l,4,7-triazatricyclo[5.2.1.0 4 10]decanyl chromium trichloride l,4,7-triazatricyclo[5.2.1.0 4 10]decanyl iron trichloride l,4,7-triazatricyclo[5.2.1.0 4 10]decanyl iron dichloride l,4,7-triazatricyclo[5.2.1.0 4 10]decanyl chromium dichloride l,4,7-triazatricyclo[5.2.1.0 4 10]decanyl titanium trichloride As was said initially, the invention also relates to a process for the preparation of the transition metal complex described above. The preparation process is characerized by reacting a triaza compound of the formula (9) wherein R is an organic group such as a hydro carbyl, a silyl or a siloxy or a hydrogen, and each of Ri-Rβ is the same as above (see formula (2)), a transition metal compound of the formula (10) MX m (10) wherein M, X and m are the same as above (see formula (1)), and a strong base, in the sequence (triaza compound + transition, metal compound) + strong base, or the order (triaza compound + strong base) + transition metal compound, to give said transition metal complex. R is preferably a C C 6 alkyl, a tri-CrCβ alkylsilyl or a hydrogen. With respect to the details and specific definitions of the structures of compounds (9) and (10), see the product specifications concerning the above ligand (2) and transition metal complex (1), respectively. According to said first reaction sequence, the triaza compound and the transition metal compound are reacted into an intermediate, which is in this connection called a precursor complex. Then, the precursor complex is reacted with the strong base to form the claimed triaza transition metal complex. Preferably, a complexing agent is used to facilitate the formation of the precursor complex. Thus, the triaza compound is reacted with the transition metal compound and a complexating electron donor compound to form said precursor complex comprising said triaza compound, said transition metal compound and said complexating electron donor compound. Most preferably, the triaza compound is reacted with a starting complex of said transition metal compound and said complexating electron donor compound. A suitable complexating electron donor compound is e.g. tetrahydrofurane. When preparing a precursor complex, it preferably has the following formula (11) wherein R, R Rβ, M, X, m and n are as defined above (see formulas (1), (2) and (9)), CED is said complexating electron donor and p is an integer 1 to 3. The strong base may be any base which is capable of removing the substituent R from the carbon atom connected with all three nitrogen atoms, see above. Preferably, it is an organoalkali compound having the formula R'A, wherein R' is a C C 12 hydrocarbyl and A is an alkali metal. Most preferably, it is benzyl potassium. Above, a transition metal complex having a tri-N-uni-C-dentate ligand as at least one of the ligands L was described. During the synthesis of that complex, another new useful compound was found. As an immediate reaction product between the triaza compound (9) and the transition metal compound (10), a transition metal complex having a tri-N-dentate ligand was formed. See the precursor complex (11) above. The triaza compound was coordinated to the transition metal through the three nitrogen atoms without losing the substituent on its central carbon. With some metals, this product was formed spontaneously and could be isolated. Thus, the present invention also relates to a transition metal complex containing a tri-N-dentate triaza ligand (within brackets) of the formula (12) wherein the R of the triaza ligand within brackets is an organic group or hydrogen, each of R Rβ is independently selected from organic groups having from 1 to 10 carbon atoms, M is a central atom which is a metal selected from Groups 4-8 of the Periodic Table of the Elements, each X is independently an unidentate organic or halogen ligand, CED is a complexating dectron donor, m is the coordination number or number of coordination sites on the central atom M, n is the number of the triaza ligands, and p is an integer 1 to 3. R may be any organic group such as an alkyl, aryl, silyl or siloxy group. Typically R is a C C 6 alkyl or a trialkyl silyl group. Most preferably, R is hydrogen. With the tri-N-dentate triaza ligand, the same structural details prevail as for the tri- N-uni-C-dentate ligand described above. Thus, said organic groups of at least one of the pairs: R 2 and R 3 , R-j and R 5 , and Re and R. are preferably interconnected to form a bridge structure. The groups of all of the pairs: R 2 and R 3 , R-t and R 5 , R^ and Ri are most preferably interconnected to form bridge structures which are selected from 2 carbon and 3 carbon chanis. M of formula (12) is preferably selected from chromium Fe, Cr, titanium Ti and zirconium Zr. X is preferably selected from a C C 3 alkyl and a halogen, most preferably from methyl and chlorine Cl. The integer n of formula (12) is preferably 1 or 2. The complex of formula (12) is preferably an intermediate when preparing the complex according to formula (1). Under proper reaction conditions the complex of formula (12) may react further to form a complex of the formula (1) and RX may then be bound to the complex of formula (1) or they may escape from the system. The invention also relates to a catalyst system for the polymerization of ethylenically unsaturated compounds. It comprises a transition metal complex according to the above description and a cocatalyst selected from an aluminoxane having one of the following formulas (13) (13 linear) (13 cyclic) (OAlR") c (13 general) wherein each R" is independently selected from a Ci-Cio alkyl and q is an integer between 1 and 40, and an organic compound having the formula (14) (R" M'X s . T ) t (14) wherein R"' is a CpCio hydrocarbyl, X is a halogen, r is 1, 2 or 3, s is the valency of M', M' is a metal selected from Groups 1 to 3 and 13 of the Periodic Table of the Elements (IUPAC 1990), and t is 1 or 2. Said organic compound, also called an ionic catalyst activator, can for example be a boron or aluminium compound, such as triphenylpentafluoroboron B(C 6 F 5 ) 3 or triphenylcarbenium tetraphenylpentafluoroborate (C 6 H 5 ) 3 C + B " (C 6 F 5 ) 4 . Preferably, said cocatalyst is a Cι-C 10 aluminoxane, preferably a C C 6 aluminoxane, most preferably methyl aluminoxane. Further, the invention relates to the use of the above described catalyst system for the polymerization of one or several ethylenically unsaturated compounds. In the claimed polymerization process, at least one polymerizable ethylenically unsaturated compound is under polymerization conditions contacted with a catalyst system of the above described type. In the polymerization process according to the invention, the atomic ratio Al/M or M'/M is preferably between 10 and 10000, most preferably between 100 and 2000. The polymerizable ethylenically unsaturated compound is preferably selected from ethylene, a C 3 -C 20 -α-olefin, a conjugated C -C 12 diene and a C 5 -C 1 -α-ω-diolefin and polymerizable combinations thereof. Most preferably, it is ethylene. Examples All operations were carried out in argon or nitrogen atmosphere using standard Schlenk, vacuum and dry box techniques. Solvents were dried with potassium benzophenone cetyl and distilled under argon prior to use. 1,5,9-triazatricyclo- [7.3.1.0] 5,13 tridecane was synthesized from l,5,7-triaza[4.4.0]bicyclo-dec-5-ene (Fluka) using methods described in the literature. 1,4,7-triazatricyclo [5.2.1.0 4 ' 10 ] decane was synthesized from 1,4,7-triazacyclononane (Fluka) via a published method. FeCl 2 (Fluka). FeCl 3 (Merck) and TiCL t (Aldrich) were used without further purification. CrCl 3 (Merck) was converted into CrCl 3 -3 (THF) prior to use. The Η-NMR spectra were recorded using a JEOL JNM-EX 270 Mhz FT NMR spectrometer with tetramethylsilane (TMS) as an internal reference. The MS spectra were recorded by a VG Quadrupole TRIO 2 electronic ionization method and direct probe 70 eV spectrometer. The polymerization tests were carried out using MAO, 30% solution in toluene purchased from Albermarle. Test polymerizations were carried out in pentane at 80 °C with no hydrogen present using an Al/Zr ratio of 1000 unless otherwise stated. A Buchi 2 L stirred reactor with mantle heating was used for the polymerization tests. Example 1 Preparation of the 1,5,9-triazatricyclo [7.3.1.0] 5 ' 13 tridecanyl chromium trichloride (THF) 2 complex, C 18 H 35 Cl 3 CrN 3 θ 2 . Solid CrCl 3 (THF) 3 (1.31 mmol) was dissolved under argon atmosphere at room temperature into 20 ml of dry THF to give a blue- violet solution. Then 1,5,9-triazatricyclo [7.3.1.0] ' tridecane (1.31 mmol, 238 mg) was dissolved in 20 ml or dry THF to give a transparent and colorless solution. The CrCl 3 (THF) 3 solution was then added dropwise during 2 hours at -78 °C into the triazatricyclotridecane solution and stirred overnight at -30 °C to give a dark green solution and a green precipitate. The solid green product was filtered and washed with more THF. All solvents were removed in a vacuum and the green solid product was analyzed. The yield was 20%. Example 2 Preparation of the 1,5,9-triazatricyclo [7.3.1.0] ' tridecanyl chromium dichloride (THF) complex, C 14 H 26 Cl 2 CrN 3 O. Solid CrCl 3 (THF) 3 (1.31 mmol) was dissolved under argon atmosphere at room temperature into 20 ml of dry THF to give a blue- violet solution. Then 1,5,9-triazatricyclo [7.3.1.0] 5 13 tridecane (1.31 mmol, 238 mg) was dissolved in 20 ml of dry THF to give a transparent and colorless solution. CrCi 3 (THF) 3 solution was then added dropwise during 2 hours at 78 °C into the tri- azatricyclotridecane solution and then stirred 2 hours at -30 °C to give a dark green solution and a green precipitate. Solid benzyl potassium (1.31 mmol, 171 mg) was then added at -30 °C and the mixture the stirred 18 h at 0 °C to give a light green precipitate and a transparent whitish solution. All solvents were removed in a vacuum and the solid light green raw product was analyzed. The yield was 90%. The purity of the product was 80,3%^,. The product contained 19,7% w KC1 and approximately 1 eq. of THF. The product is insoluble in THF, toluene, dichloromethane, ether and pentane. Example 3 Preparation of (l,4,7-triazatricyclo[5.2.1.0 4,10 ]decane) TiC- . (1,4,7-triazatricyclo- [5.2.1.0 4,10 ]decane (500 mg, 2.76 mmol) was added to 30 ml of ether followed by addition of TiC (524 mg, 2.76 mmol) at -30 °C resulting in bright yellow solution. The mixture was stirred at +25 °C overnight. Ether was removed and 30 ml of toluene was added followed by refluxing for 1.5 hours. The yellow slurry was filtered and washed 2x10 ml of toluene. Removal of remaining solvent resulted in powdery yellow solid. Test polymerization data Polymerizations were carried out in a 2 1 stainless steel autoclave reactor equipped with a paddle stirred and a continuous supply of ethylene. Hydrogen and comonomer, if used were fed to the reactor simultaneously with ethylene. MFR's of the produced polymers were measured according to the ISO-1133 method. GPC was used to determine the average molecular weights and molecular weight distributions of the produced polymers. Polymerization temperature was 80 °C and ethylene pressure 10 bar. The amount of substances and the polymerization results are shown in Table 1. Table 1 Polymerization of ethylene with various homogenous TAT catalysts in pentane. Polymerization temperature 80 °C. Ethylene pressure 10 bar. Comonomer used was 1-hexene. TAT-13 = 1,5,9-triazatricyclo [7.3.1.0] 5 13 tridecanyl. t

Claims: Claims 1. A triaza transition metal complex having the formula (1) „MX m - n (1) wherein each L is independently a ligand which is multidentate by adjacent cooordinating atoms, M is the central atom which is a metal selected from Groups 4-8 of the Periodic Table of the Elements (IUPAC 1990), each X is independently a unidentate organic or halogen ligand, m is the coordination number or number of coordination sites on the central atom M, and n is the number of the ligands L which is an integer from 1 to m, characterized in that at least one of the ligands L has the formula (2) wherein each of R 1 - - 5 is independently selected from hydrogen and organic groups having from 1 to 10 carbon atoms and the ligand L is coordinated to the central atom M by one, two, three or four of the three nitrogen atoms and/or the carbon atom of the ligand L according to the formula (2). 2. A transition metal complex according to claim 1, characterized in that said organic groups of at least one of the pairs: R 2 and R 3 , t and R 5 , and Rs and are interconnected to form a bridge structure. 3. A transition metal complex according to claim 1 or 2, characterized in that the groups of all of the pairs: R 2 and R 3 , R 4 and R 5 , R ό and R t are interconnected to form bridge structures which are selected from unsubstituted 1,3-propylene and ethylene. 4. A transition metal complex according to claim 1, 2 or 3, characterized in that M of formula (1) is selected from iron Fe, chromium Cr, titanium Ti and zirconium Zr. 5. A transition metal complex according to any preceding claim, characterized in that X of formula (1) is selected from a -C 3 alkyl and a halogen. 6. A transition metal complex according to claim 5, characterized in that X is selected from methyl and chlorine Cl. 7. A transition metal complex according to any preceding claim, characterized in that n of formula (1) is selected from 1 and 2. 8. A transition metal complex according to any preceding claim, characterized in that it is a l,5,9-triazatricyclo[7.3.1.0] 5 ' 13 tridecanyl chromium dichloride of the formula (3): 9. A transition metal complex according to any of claims 1-7, characterized in that it is a l,5,9-triazatricyclo[7.3.1.0] 5 ' 13 tridecanyl zirconium trichloride of the formula (4): 10. A transition metal complex according to any of claims 1-7, characterized in that it is a bis{ l,5,9-tπazatricyclo[7.3.1.0] ' tridecanyl} zirconium dichloride of the formula (5): 11. A transition metal complex according to any of claims 1-7, characterized in that it is a l,4,7-triazatricyclo[5.2.1.0 4 ' 10 ] decanyl chromium dichloride of the formula (6): 12. A transition metal complex according to any of claims 1-7, characterized in that it is a l,4,7-triazatricyclo[5.2.1.0 4 ' 10 ] decanyl titanium trichloride of the formula (7): 13. A transition metal complex according to any of claims 1-7, characterized in that it is a bis{l,4,7-triazatricyclo[5.2.1.0 4 ' 10 ] decanyl} zirconium dichloride of the formula (8): 14. A process for the preparation of a transition metal complex according to any of claims 1-13, characterized by reacting a triaza compound of the formula (9) wherein R is a Cι-C 6 alkyl, a tri-C C6 alkylsilyl or a hydrogen and each of R 1 -R 5 is the same as above, a transition metal compound of the formula (10) MX„ (10) wherein M, X and m are the same as above, and preferably a strong base, most preferably in the order (triaza compound + transition metal compound) + strong base or the order (triaza compound + strong base) + transition metal compound, to give said transition metal complex. 15. A process according to claim 14, characterized in that said triaza compound is reacted with said transition metal compound and, preferably, a complexating electron donor compound to form a precursor complex comprising said triaza compound, said transition metal compound and, preferably, said complexating electron donor compound, and that said precursor complex is then reacted with said strong base. 16. A process according to claim 15, characterized in that said triaza compound is reacted with a starting complex of said transition metal compound and said complexating electron donor compound. 17. A process according to claim 15 or 16, characterized in that said complexating electron donor compound is tetrahydrofurane. 18. A process according to any of claim 14-17, characterized in that said precursor complex has essentially the following formula (11) wherein R, R R δ , M, X, m and n are as defined above, CED is said complexating electron donor and p is an integer 1 to 3. 19. A process according to any of claims 14-18, characterized in that said strong base is an organoalkali compound having the formula R'A, wherein R' is a -C 12 hydrocarbyl and A is an alkali metal. 20. A process according to claim 19, characterized in that said strong base is benzyl potassium. 21. A tri-N-dentate transition metal complex, characterized in that it has the formula (12) wherein the R of the triaza ligand within brackets is a C C 6 alkyl, a tri-Ci-C ό alkylsilyl or a hydrogen, each of RpRβ is independently selected from organic groups having from 1 to 10 carbon atoms, M is a central atom which is a metal selected from Groups 4-8 of the Periodic Table of the Elements, each X is independently an unidentate organic or halogen ligand, m is the coordination number or number of coordination sites on the central atom M, and n is the number of the triaza ligands. 22. A transition metal complex according to claim 21, characterized in that said organic groups of at least one of the pairs: R 2 and R , R4 and R 5 , and R and Ri are interconnected to form a bridge structure. 23. A transition metal complex according to claim 21 or 22, characterized in that the groups of all of the pairs: R 2 and R 3 , R 4 and R 5 , Rs and R \ are interconnected to form bridge structures which are selected from unsubstituted 1,3-propylene and ethylene. 24. A transition metal complex according to claim 21, 22 or 23, characterized in that M of formula (12) is selected from chromium Fe, Cr, titanium Ti and zirconium Zr. 25. A transition metal complex according to any of claims 21-24, characterized in that X of formula (12) is selected from a C C 3 alkyl and a halogen. 26. A transition metal complex according to claim 25, characterized in that X is selected from methyl and chlorine Cl. 27. A transition metal complex according to any of claims 21-26, characterized in that n of formula (12) is selected from 1 and 2. 28. A catalyst system for the polymerization of ethylenically unsaturated compounds, characterized in that it comprises a transition metal complex according to any of claims 1-13 or 18-27 and a cocatalyst selected from an aluminoxane having one of the following formulas (13) (13 linear) (13 cyclic) (OAlR") q (1 general) wherein each R" is independently selected from a Ci-Cio alkyl and q is an integer between 1 and 40, and an organic compound having the formula (14) (R-VM'X - (14) wherein R"' is a CrC 10 hydrocarbyl, X' is a halogen, r is 1, 2 or 3, s is the valency of M', M' is a metal selected from Groups 1 to 3 and 13 of the Periodic Table of the Elements (IUPAC 1990), and t is 1 or 2. 29. A catalyst system according to claim 28, characterized in that said cocatalyst is a C Cio aluminoxane, preferably a Cι-C 6 aluminoxane, most preferably methyl aluminoxane. 30. Process for the polymerization of one or several ethylenically unsaturated compounds, characterized in that, under polymerization conditions, at least one polymerizable ethylenically unsaturated compound is contacted with a catalyst system according to one of claims 28 or 29. 31. Process according to claim 30, characterized in that the atomic ratio Al/M or M'/M is between 10 and 10000, preferably between 100 and 2000. 32. Process according to claim 30 or 31, characterized in that said polymerizable ethylenically unsaturated compound is selected from ethylene, a C 3 -C 20 -α-olefin, a conjugated C -Cι 2 diene and a C 5 -C 14 -α-ω-diolefin and polymerizable combinations thereof. 33. Process according to claim 32, characterized in that said polymerizable ethylenically unsaturated compound is ethylene.

Inventors: ANDELL OVE, KETOLA LASSE, MAARANEN JANNE, ANDELL, OVE, KETOLA, LASSE, MAARANEN, JANNE
Applicants: ANDELL OVE, BOREALIS AS, KETOLA LASSE, MAARANEN JANNE, ANDELL, OVE, BOREALIS A/S, KETOLA, LASSE, MAARANEN, JANNE
Application year: 2000
Main classification: B01J31
IPC codes: B01J31, C07F7, C07F11, C08F10