WO1997042235A1

WO1997042235A1 - Process for the production of polymers containing cyclic olefins

Info

Publication number: WO1997042235A1
Application number: PCT/NL1997/000240
Authority: WO
Inventors: Maurits Frederik Hendrik Van Tol; Johannes Antonius Maria Van Beek; Paulus Johannes Jacobus Pieters
Original assignee: Dsm N.V.
Priority date: 1996-05-03
Filing date: 1997-05-01
Publication date: 1997-11-13
Also published as: AU2411697A

Abstract

The invention relates to a process for the production of polymers containing cyclic olefins by contacting, under polymerisation conditions, at least one cyclic and/or polycyclic olefin, optionally in the presence of α-olefins, with a catalyst comprising a transition metal complex and a co-catalyst. The invention is characterized in that the transition metal complex consists of a reduced transition metal, chosen from groups 4-6 of the Periodic Table of the Elements, with a multidentate monoanionic ligand and with two monoanionic ligands. In particular the reduced transition metal is titanium (Ti).

Description

PROCESS FOR THE PRODUCTION OF POLYMERS CONTAINING CYCLIC OLEFINS

The present invention relates to a process for the production of polymers containing cyclic olefins. In particular the invention relates to a process for producing such polymers showing excellent transparency, excellent electrical insulative properties, high heat deflection temperature, high resistance to polar solvents, very good hydrolytic stability and easy processability. It is known, e.g. from Kaminsky (Catalysis

Today 10_. (1994) 257-271), that cycloalkenes can be polymerized by metallocenes to form crystalline polycycloalkenes which show extremely high melting points. Due to this high melting temperature these homopolymers are, however, of limited use.

Copolymers of cyclo-alkenes with ethylene, with a relatively high incorporation (above about 14 mol%) of the cyclo-alkene, are amorphous and transparent with a glass transition temperature that allows the use of these materials, for example, for optical disk fabrication or for polymer optical fibre (POF) applications.

At lower cyclo-olefin contents in the copolymers, the copolymers show elastomeric properties. EP-A-501 370 teaches the polymerisation of polycyclic olefins, in particular norbornene and tetracyclododecene, and the copolymerisation of polycyclic olefins and/or 1-olefins with a very narrow molecular weight distribution (Mw/Mn ≤ 2 , in particular Mw/Mn ≤ 1.4) without ring opening, using a stereo- rigid, chiral metallocene in combination with aluminoxane. This process yields however very narrow molecular weight distributions so that the application of the resins produced is limited, due to difficult processing.

EP-A-407 870 teaches the polymerisation of polycyclic olefins, without ring opening, using stereo- rigid, chiral metallocene/aluminoxane mixtures, in particular at temperatures up to 70 C.

It would be economically advantageous to have availabe a process offering the flexibility of polymerisation of cyclic and polycyclic olefins and copolymerisation of cyclic and polycyclic olefins with or without α-olefins at higher temperatures, allowing high polymerisation rates with a high comonomer affinity, a high molecular weight capability and allowing the production of resins having a relatively broad molecular weight distribution, if required.

The purpose of the present invention is to provide such a process, furthermore offering the possibility to incorporate very low to very high amounts of cyclic and/or polycyclic olefines in the copolymers. The process described in this invention makes the production of the resins concerned very interesting from a commercial point of view as a consequence of the process' flexibility and low catalyst-system costs. The higher polymerisation temperatures not only result in higher polymerisation rates but also allow the use of cocatalysts other than aluminoxanes, e.g. borates.

The process of the invention for the production of polymers containing cyclic olefins by contacting, under polymerisation conditions, at least one cyclic and/or polycyclic olefin, optionally in the presence of α-olefins, in the presence of the present catalyst composition. The catalyst composition includes at least one complex comprising a reduced valency transition metal (M) selected from groups 4-6 of the Periodic Table of Elements, a multidentate monoanionic ligand (X), two monoanionic ligands (L), and, optionally, additional ligands (K). More specifically, the complex of the catalyst composition of the present invention is represented by the following formula (I):

x (i)

I

M - L₂

I κ_m

wherein the symbols have the following meanings:

M a reduced transition metal selected from group 4, 5 or 6 of the Periodic Table of Elements;

X a multidentate monoanionic ligand represented by the formula: (Ar-R_t-)_SY(-R_t-DR'_n)_q;

Y a cyclopentadienyl, amido (-NR'-), or phosphido group (-PR'-), which is bonded to the reduced transition metal M;

R at least one member selected from the group consisting of (i) a connecting group between the Y group and the DR'_n group and (ii) a connecting group between the Y group and the Ar group, wherein when the ligand X contains more than one R group, the R groups can be identical to or different from each other;

D an electron-donating hetero atom selected from group 15 or 16 of the Periodic Table of Elements; R' a substituent selected from the group consisting of a hydrogen, hydrocarbon radical and hetero atom-containing moiety, except that R' cannot be hydrogen when R' is directly bonded to the electron-donating hetero atom D, wherein when the multidentate monoanionic ligand X contains more than one substituent R', the substituents R' can be identical or different from each other;

Ar an electron-donating aryl group;

L a monoanionic ligand bonded to the reduced transition metal M, wherein the monoanionic ligand L is not a ligand comprising a cyclopentadienyl, amido (-NR'-), or phosphido (-PR'-) group, and wherein the monoanionic ligands L can be identical or different from each other;

K a neutral or anionic ligand bonded to the reduced transition metal M, wherein when the transition metal complex contains more than one ligand K, the ligands K can be identical or different from each other; m the number of the K ligands, wherein when the K ligand is an anionic ligand m is 0, 1, or 2, and when K is a neutral ligand, m increases by one for each neutral K ligand; n the number of the R' groups bonded to the electron-donating hetero atom D, wherein when D is selected from group 15 of the Periodic Table of Elements n is 2, and when D is selected from group 16 of the Periodic Table of Elements n is 1; q,s q and s are the number of (-R_t-DR'_n) groups and (Ar-R_t-) groups bonded to group Y, respectively, wherein q + s is an integer not less than 1; and t the number of R groups connecting each of (i) the Y and Ar groups and (ii) the Y and DR'_n groups, wherein t is selected independently as 0 or 1.

A few examples of transition metal complexes according to the invention are presented in Table 1.

The accompanying drawings illustrate the present invention. In such drawings:

FIG. 1 is a schematic view of a cationic active site of a trivalent catalyst complex in accordance with an embodiment of the present invention; and FIG. 2 is a schematic view of a neutral active site of a trivalent catalyst complex of a dianionic ligand of a conventional catalyst complex according to WO-A-93/19104.

Various components (groups) of the transition metal complex are discussed below in more detail.

(a) The Transition Metal (M)

The transition metal in the complex is selected from groups 4-6 of the Periodic Table of Elements. As referred to herein, all references to the Periodic Table of Elements mean the version set forth in the new IUPAC notation found on the inside of the cover of the Handbook of Chemistry and Physics, 70th edition, 1989/1990, the complete disclosure of which is incorporated herein by reference. More preferably, the transition metal is selected from group 4 of the Periodic Table of Elements, and most preferably is titanium (Ti).

The transition metal is present in reduced form in the complex, which means that the transition metal is in a reduced oxidation state. As referred to herein, "reduced oxidation state" means an oxidation state which is greater than zero but lower than the highest possible oxidation state of the metal (for example, the reduced oxidation state is at most M³⁺ for a transition metal of group 4, at most M⁴⁺ for a transition metal of group 5 and at most M⁵⁺ for a transition metal of group 6).

(b) The X Ligand

The X ligand is a multidentate monoanionic ligand represented by the formula: (Ar-R_t-)_SY(-R_t-DR'_n)_q.

As referred to herein, a multidentate monoanionic ligand is bonded with a covalent bond to the reduced transition metal (M) at one site (the anionic site, Y) and is bonded either (i) with a coordinate bond to the transition metal at one other site (bidentate) or (ii) with a plurality of coordinate bonds at several other sites (tridentate, tetradentate, etc.). Such coordinate bonding can take place, for example, via the D heteroatom or Ar group(s). Examples of tridentate monoanionic ligands include, without limitation, Y-R_t-DR ' _n_₁-R_t-OR'„ and Y(-R-DR'_n)₂. It is noted, however, that heteroatom(s) or aryl substituent(s) can be present on the Y group without coordinately bonding to the reduced transition metal M, so long as at least one coordinate bond is formed between an electron-donating group D or an electron donating Ar group and the reduced transition metal M. R represents a connecting or bridging group between the DR'_n and Y, and/or between the electron- donating aryl (Ar) group and Y. Since R is optional, "t" can be zero. The R group is discussed below in paragraph (d) in more detail.

(c) The Y Group

The Y group of the multidentate monoanionic ligand (X) is preferably a cyclopentadienyl, amido (-NR'-), or phosphido (-PR'-) group.

Most preferably, the Y group is a cyclopentadienyl ligand (Cp group). As referred to herein, the term cyclopentadienyl group encompasses substituted cyclopentadienyl groups such as indenyl, fluorenyl, and benzoindenyl groups, and other polycyclic aromatics containing at least one 5-member dienyl ring, so long as at least one of the substituents of the Cp group is an R_t-DR'_n group or R_t-Ar group that replaces one of the hydrogens bonded to the five-member ring of the Cp group via an exocyclic substitution.

Examples of a multidentate monoanionic ligand with a Cp group as the Y group (or ligand) include the following (with the (-R_t-DR'_n) or (Ar-R_t-) substituent on the ring) : R R

R-DR '_n R-Ar

The Y group can also be a hetero cyclopentadienyl group. As referred to herein, a hetero cyclopentadienyl group means a hetero ligand derived from a cyclopentadienyl group, but in which at least one of the atoms defining the five-member ring structure of the cyclopentadienyl is replaced with a hetero atom via an endocyclic substitution. The hetero Cp group also includes at least one R_t-DR'_n group or R_t-Ar group that replaces one of the hydrogens bonded to the five-member ring of the Cp group via an exocyclic substitution. As with the Cp group, as referred to herein the hetero Cp group encompasses indenyl, fluorenyl, and benzoindenyl groups, and other polycyclic aromatics containing at least one 5-member dienyl ring, so long as at least one of the substituents of the hetero Cp group is an R_t-DR'_n group or R_t-Ar group that replaces one of the hydrogens bonded to the five-member ring of the hetero Cp group via an exocyclic substitution.

The hetero atom can be selected from group 14, 15 or 16 of the Periodic Table of Elements. If there is more than one hetero atom present in the five- member ring, these hetero atoms can be either the same or different from each other. More preferably, the hetero atom(s) is/are selected from group 15, and still more preferably the hetero atom(s) selected is/are phosphorus.

By way of illustration and without limitation, representative hetero ligands of the X group that can be practiced in accordance with the present invention are hetero cyclopentadienyl groups having the following structures, in which the hetero cyclopentadienyl contains one phosphorus atom (i.e., the hetero atom) substituted in the five-member ring:

R R-DR

It is noted that, generally, the transition metal group M is bonded to the Cp group via an h_. ⁵ bond.

The other R' exocyclic substituents (shown in formula (III)) on the ring of the hetero Cp group can be of the same type as those present on the Cp group, as represented in formula (II). As in formula (II), at least one of the exocyclic substituents on the five- member ring of the hetero cyclopentadienyl group of formula (III) is the R_t-DR'_n group or the R_t-Ar group. The numeration of the substitution sites of the indenyl group is in general and in the present description based on the IUPAC Nomenclature of Organic Chemistry 1979, rule A 21.1. The numeration of the substituent sites for indene is shown below. This numeration is analogous for an indenyl group:

The Y group can also be an amido (-NR'-) group or a phosphido (-PR'-) group. In these alternative embodiments, the Y group contains nitrogen (N) or phosphorus (P) and is bonded covalently to the transition metal M as well as to the (optional) R group of the (-R_t-DR'_n) or (Ar-R_t-) substituent.

(d) The R Group

The R group is optional, such that it can be absent from the X group. Where the R group is absent, the DR'_n or Ar group is bonded directly to the Y group (that is, the DR'_n or Ar group is bonded directly to the Cp, amido, or phosphido group). The presence or absence of an R group between each of the DR'_n groups and/or Ar groups is independent.

Where at least one of the R groups is present, each of the R group constitutes the connecting bond between, on the one hand the Y group, and on the other hand the DR'_n group or the Ar group. The presence and size of the R group determines the accessibility of the transition metal M relative to the DR'_n or Ar group, which gives the desired intramolecular coordination. If the R group (or bridge) is too short or absent, the donor may not coordinate well due to ring tension. The R groups are each selected independently, and can generally be, for example, a hydrocarbon group with 1-20 carbon atoms (e.g., alkylidene, arylidene, aryl alkylidene, etc.). Specific examples of such R groups include, without limitation, methylene, ethylene, propylene, butylene, phenylene, whether or not with a substituted side chain. Preferably, the R group has the following structure:

(-CR',-). (IV)

where p = 1-4. The R' groups of formula (IV) can each be selected independently, and can be the same as the R' groups defined below in paragraph (g).

In addition to carbon, the main chain of the R group can also contain silicon or germanium. Examples of such R groups are: dialkyl silylene (-SiR'₂-), dialkyl germylene (-GeR'₂-), tetra-alkyl silylene (-SiR '₂-SiR '₂-) , or tetraalkyl silaethylene (-SiR '₂CR '₂-) . The alkyl groups in such a group preferably have 1-4 carbon atoms and more preferably are a methyl or ethyl group.

(e) The DR'_n Group

This donor group consists of an electron¬ donating hetero atom D, selected from group 15 or 16 of the Periodic Table of Elements, and one or more substituents R' bonded to D. The number (n) of R' groups is determined by the nature of the hetero atom D, insofar as n being 2 if D is selected from group 15 and n being 1 if D is selected from group 16. The R' substituents bonded to D can each be selected independently, and can be the same as the R' groups defined below in paragraph (g), with the exception that the R' substituent bonded to D cannot be hydrogen. The hetero atom D is preferably selected from the group consisting of nitrogen (N), oxygen (0), phosphorus (P) and sulphur (S); more preferably, the hetero atom is nitrogen (N). Preferably, the R' group is an alkyl, more preferably an n-alkyl group having 1- 20 carbon atoms, and most preferably an n-alkyl having 1-8 carbon atoms. It is further possible for two R' groups in the DR'_n group to be connected with each other to form a ring-shaped structure (so that the DR'_n group can be, for example, a pyrrolidinyl group). The DR'_n group can form coordinate bonds with the transition metal M.

(f) The Ar Group

The electron-donating group (or donor) selected can also be an aryl group (C₆R'_S), such as phenyl, tolyl, xylyl, mesityl, cumenyl, tetramethyl phenyl, pentamethyl phenyl, a polycyclic group such as triphenylmethane, etc. The electron-donating group D of formula (I) cannot, however, be a substituted Cp group, such as an indenyl, benzoindenyl, or fluorenyl group.

The coordination of this Ar group in relation to the transition metal M can vary from h¹ to ή⁶.

(g) The R' Group

The R' groups may each separately be hydrogen or a hydrocarbon radical with 1-20 carbon atoms (e.g. alkyl, aryl, aryl alkyl and the like as shown in Table

1).

Examples of alkyl groups are methyl, ethyl, propyl, butyl, hexyl and decyl. Examples of aryl groups are phenyl, mesityl, tolyl and cumenyl. Examples of aryl alkyl groups are benzyl, pentamethylbenzyl, xylyl, styryl and trityl. Examples of other R' groups are halides, such as chloride, bromide, fluoride and iodide, methoxy, ethoxy and phenoxy. Also, two adjacent hydrocarbon radicals of the Y group can be connected with each other to define a ring system? therefore the Y group can be an indenyl, a fluorenyl or a benzoindenyl group. The indenyl, fluorenyl, and/or benzoindenyl can contain one or more R' groups as substituents. R' can also be a substituent which instead of or in addition to carbon and/or hydrogen can comprise one or more hetero atoms of groups 14-16 of the Periodic Table of Elements. Thus, a substituent can be, for example, a Si-containing group, such as Si(CH₃)₃.

(h) The L Group

The transition metal complex contains two monoanionic ligands L bonded to the transition metal M. Examples of the L group ligands, which can be identical or different, include, without limitation, the following: a hydrogen atom; a halogen atom; an alkyl, aryl or aryl alkyl group; an alkoxy or aryloxy group; a group comprising a hetero atom selected from group 15 or 16 of the Periodic Table of Elements, including, by way of example, (i) a sulphur compound, such as sulphite, sulphate, thiol, sulphonate, and thioalkyl, and (ii) a phosphorus compound, such as phosphite, and phosphate. The two L groups can also be connected with each other to form a dianionic bidentate ring system.

These and other ligands can be tested for their suitability by means of simple experiments by one skilled in the art.

Preferably, L is a halide and/or an alkyl or aryl group; more preferably, L is a Cl group and/or a C_!-C₄ alkyl or a benzyl group. The L group, however, cannot be a Cp, amido, or phosphido group. In other words, L cannot be one of the Y groups.

(i) The K Ligand

The K ligand is a neutral or anionic group bonded to the transition metal M. The K group is a neutral or anionic ligand bonded to M. When K is a neutral ligand K may be absent, but when K is monoanionic, the following holds for K_m: m = 0 for M³⁺ m = 1 for M⁴⁺ m = 2 for M⁵⁺

On the other hand, neutral K ligands, which by definition are not anionic, are not subject to the same rule. Therefore, for each neutral K ligand, the value of m (i.e., the number of total K ligands) is one higher than the value stated above for a complex having all monoanionic K ligands.

The K ligand can be a ligand as described above for the L group or a Cp group (-C_SR'₅), an amido group (-NR'₂) or a phosphido group (-PR'₂). The K group can also be a neutral ligand such as an ether, an amine, a phosphine, a thioether, among others.

If two K groups are present, the two K groups can be connected with each other via an R group to form a bidentate ring system.

As can also be seen from formula (I), the X group of the complex contains a Y group to which are linked one or more donor groups (the Ar group(s) and/or DR'_n group(s)) via, optionally, an R group. The number of donor groups linked to the Y group is at least one and at most the number of substitution sites present on a Y group. With reference, by way of example, to the structure according to formula (II), at least one substitution site on a Cp group is made by an R_t-Ar group or by an R_t-DR'_n group (in which case q + s = 1). If all the R' groups in formula (II) were R_t-Ar groups, R_t-DR'_n groups, or any combination thereof, the value of (q + s) would be 5.

One preferred embodiment of the catalyst composition according to the present invention comprises a transition metal complex in which a bidentate/monoanionic ligand is present and in which the reduced transition metal has been selected from group 4 of the Periodic Table of Elements and has an oxidation state of +3.

In this case, the catalyst composition according to the invention comprises a transition metal complex represented by formula (V):

X

I M(III) - L₂, (V)

I

where the symbols have the same meaning as described above for formula (I) and where M(III) is a transition metal selected from group 4 of the Periodic Table of Elements and is in oxidation state 3+.

Such a transition metal complex has no anionic K ligands (for an anionic K, m = 0 in case of M³⁺) .

It should be pointed out that in WO-A- 93/19104, transition metal complexes are described in which a group 4 transition metal in a reduced oxidation state (3+) is present. The complexes described in WO-A- 93/19104 have the general formula:

Cp_a(ZY)_bML_c (VI)

The Y group in this formula (VI) is a hetero atom, such as phosphorus, oxygen, sulfur, or nitrogen bonded covalently to the transition metal M (see p. 2 of WO-A- 93/19104). This means that the Cp_a(ZY)_b group is of a dianionic nature, and has the anionic charges residing formerly on the Cp and Y groups. Accordingly, the Cp_a(ZY)_b group of formula (VI) contains two covalent bonds: the first being between the 5-member ring of the Cp group and the transition metal M, and the second being between the Y group and the transition metal. By contrast, the X group in the complex according to the present invention is of a monoanionic nature, such that a covalent bond is present between the Y group (e.g., the Cp group) and transition metal, and a coordinate bond can be present between the transition metal M and one or more of the (Ar-R_t-) and (-R_t-DR'_n) groups. This changes the nature of the transition metal complex and consequently the nature of the catalyst that is active in the polymerization. As referred to herein, a coordinate bond is a bond (e.g., H₃N-BH₃) which when broken, yields either (i) two species without net charge and without unpaired electrons (e.g., H₃N: and BH₃) or (ii) two species with net charge and with unpaired electrons (e.g., H₃N- ⁺ and BH₃ ^"). On the other hand, as referred to herein, a covalent bond is a bond (e.g., CH₃-CH₃) which when broken yields either (i) two species without net charge and with unpaired electrons (e.g., CH₃- and CH₃- ) or (ii) two species with net charges and without unpaired electrons (e.g., CH₃ ⁺ and CH₃:^~). A discussion of coordinate and covalent bonding is set forth in Haaland et al. (Angew. Chem Int. Ed. Eng. Vol. 28, 1989, p. 992), the complete disclosure of which is incorporated herein by reference.

The following explanation is proposed, although it is noted that the present invention is in no way limited to this theory. Referring now more particularly to FIG. 2, the transition metal complexes described in WO-A- 93/19104 are ionic after interaction with the co¬ catalyst. However, the transition metal complex according to WO-A-93/19104 that is active in the polymerization contains an overall neutral charge (on the basis of the assumption that the polymerizing transition metal complex comprises, a M(III) transition metal, one dianionic ligand and one growing monoanionic polymer chain (POL)). By contrast, as shown in FIG. 1, the polymerization active transition metal complex of the catalyst composition according to the present invention is of a cationic nature (on the basis of the assumption that the polymerizing transition metal complex - based on the formula (V) structure - comprises, a M(III) transition metal, one monoanionic bidentate ligand and one growing monoanionic polymer chain (POL)).

Transition metal complexes in which the transition metal is in a reduced oxidation state, but have the following structure:

Cp - M(III) - L₂ (VII)

are generally not active in co-polymerization reactions. It is precisely the presence, in the transition metal complex of the present invention, of the DR'_n or Ar group (the donor), optionally bonded to the Y group by means of the R group, that gives a stable transition metal complex suitable for polymerization.

Such an intramolecular donor is to be preferred over an external (intermolecular) donor on account of the fact that the former shows a stronger and more stable coordination with the transition metal complex.

It will be appreciated that the catalyst system may also be formed in situ if the components thereof are added directly to the polymerization reactor system and a solvent or diluent, including liquid monomer, is used in said polymerization reactor. The catalyst composition of the present invention also contains a co-catalyst. For example, the co-catalyst can be an organometallic compound. The metal of the organometallic compound can be selected from group 1, 2, 12 or 13 of the Periodic Table of Elements. Suitable metals include, for example and without limitation, sodium, lithium, zinc, magnesium, and aluminum, with aluminum being preferred. At least one hydrocarbon radical is bonded directly to the metal to provide a carbon-metal bond. The hydrocarbon group used in such compounds preferably contains 1-30, more preferably 1-10 carbon atoms. Examples of suitable compounds include, without limitation, amyl sodium, butyl lithium, diethyl zinc, butyl magnesium chloride, and dibutyl magnesium. Preference is given to organoaluminium compounds, including, for example and without limitation, the following: trialkyl aluminum compounds, such as triethyl aluminum and tri-isobutyl aluminum; alkyl aluminum hydrides, such as di-isobutyl aluminum hydride; alkylalkoxy organoaluminium compounds; and halogen-containing organoaluminium compounds, such as diethyl aluminum chloride, diisobutyl aluminum chloride, and ethyl aluminum sesquichloride. Preferably, linear or cyclic aluminoxanes are selected as the organoaluminium compound.

In addition or as an alternative to the organometallic compounds as the co-catalyst, the catalyst composition of the present invention can include a compound which contains or yields in a reaction with the transition metal complex of the present invention a non-coordinating or poorly coordinating anion. Such compounds have been described for instance in EP-A-426,637, the complete disclosure of which is incorporated herein by reference. Such an anion is bonded sufficiently unstably such that it is replaced by an unsaturated monomer during the co¬ polymerization. Such compounds are also mentioned in EP-A-277,003 and EP-A-277,004, the complete disclosures of which are incorporated herein by reference. Such a compound preferably contains a triaryl borane or a tetraaryl borate or an aluminum equivalent thereof. Examples of suitable co-catalyst compounds include, without limitation, the following:

- dimethyl anilinium tetrakis (pentafluorophenyl) borate [C₆H₅N(CH₃)₂H]⁺ [B(C₆F₅)₄]-; dimethyl anilinium bis (7,8-dicarbaundecaborate)- cobaltate (III); - tri(n-butyl)ammonium tetraphenyl borate; triphenylcarbenium tetrakis (pentafluorophenyl) borate; dimethylanilinium tetraphenyl borate;

- tris(pentafluorophenyl) borane; and - . tetrakis(pentafluorophenyl) borate.

If the above-mentioned non-coordinating or poorly coordinating anion is used, it is preferable for the transition metal complex to be alkylated (that is, the L group is an alkyl group). As described for instance in EP-A-500,944, the complete disclosure of which is incorporated herein by reference, the reaction product of a halogenated transition metal complex and an organometallic compound, such as for instance triethyl aluminum (TEA), can also be used.

The molar ratio of the co-catalyst relative to the transition metal complex, in case an organometallic compound is selected as the co-catalyst, usually is in a range of from about 1:1 to about 10,000:1, and preferably is in a range of from about 1:1 to about 2,500:1. If a compound containing or yielding a non-coordinating or poorly coordinating anion is selected as co-catalyst, the molar ratio usually is in a range of from about 1:100 to about 1,000:1, and preferably is in a range of from about 1:2 to about 250:1.

As a person skilled in the art would be aware, the transition metal complex as well as the co¬ catalyst can be present in the catalyst composition as a single component or as a mixture of several components. For instance, a mixture may be desired where there is a need to influence the molecular properties of the polymer, such as molecular weight and in particular molecular weight distribution.

In the process according to the invention the polymerization of at least one cyclic and/or polycyclic olefin, with or without α-olefins, is carried out using a catalyst composition as described above.

In particular the cyclic olefin(s) is/are suitably chosen from the group comprising at least one monomer of formula:

CH = CH

\ / IX

(CH₂)_n

in which n is an integer from 2 to 10. Preferably the cyclic olefin is chosen from the group comprising: cyclobutene, cyclopentene, cyclohexene, cycloheptene and cyclooctene. More preferably the cyclic olefin is cyclopentene. The polycyclic olefin(s) are in particular chosen from the group comprising at least one monomer of formula:

in which R_x, R₂, R₃, R₄, R₅, R₆, R₇ and R_θ are the same or different and may represent a hydrogen atom or a C_x- C_θ alkyl group. The substituent groups in these formulae X to XIII may have different meanings. Preferably, the polycyclic olefin is chosen from the group comprising norbornene, dimethano- octahydronaphthalene (DMON) , and substituted norbornene. More preferably the polycyclic olefin is dimethano-octahydronaphthalene (DMON) or norbornene.

The optional α-olefin(s) may in particular be chosen from the group comprising ethene, propene, butene, pentene, hexene, heptene, octene and styrene (substituted or non-substituted), mixtures of which may also be used. More preferably, ethene and/or propene and/or octene and/or styrene are used as α-olefin. Most preferably ethene and/or octene and/or styrene are used as α-olefin. Mixtures of the above mentioned monomers can also be used.

According to the invention the catalyst composition can be used supported as well as non¬ supported. The supported catalysts are used mainly in gas phase and slurry processes. The carrier used may be any carrier known as carrier material for catalysts, for instance Si0_2/ A1₂0₃ or MgCl₂. These carriers may be used as such or modified, for example by silanes and/or aluminium alkyles and/or aluminoxane compounds, etc. Polymerization of the olefins can be effected in a known manner, in the gas phase as well as in a liquid reaction medium. In the latter case, both solution and suspension polymerization are suitable. Polymerisation can also be performed in the pure monomer (bulk polymerisation). The quantity of transition metal to be used in case of solution or suspension polymerisation generally is such that its concentration in the dispersion agent amounts to 10^~8 - IO^-3 mol/1, preferably IO^-7 - 10^"4 mol/1. Those skilled in the art will easily understand that the catalyst system used in accordance with this invention may also be prepared by in-situ methods, e.g. in the polymerisation reactor.

The process according to the invention will hereafter be elucidated with reference to a preparation known per se of a polymer containing cyclic olefins, which is representative of the polymerization of the monomers meant here. For the preparation of other polymers on the basis of olefinic monomers the reader is expressly referred to the multitude of publications on this subject.

The process of the present invention can be conducted as a gas phase polymerisation (e.g. in a fluidized bed reaction), solution or slurry/suspension polymerisation or solid phase powder polymerisation. For a gas phase polymerisation no solvents or dispersion media are required. For solution or slurry polymerisation processes a solvent or a combination of solvents may be employed if desired. Suitable solvents include toluene, ethylbenzene, one or more saturated straight or branched aliphatic hydrocarbons, such as butanes, pentanes, hexanes, heptanes, pentamethyl heptane or mineral oil fractions such as light or regular petrol, naphtha, kerosine or gas oil. For polymerisation under slurry conditions, a suspension utilizing a perfluorinated hydrocarbon or similar liquid may also be used.

Also excess olefinic monomer may be used as the reaction medium (so-called bulk polymerisation processes). Aromatic hydrocarbons, for instance benzene and toluene, can be used, but because of their cost as well as on account of safety considerations, it will be preferred not to use such solvents for production on a technical scale. In polymerization processes on a technical scale, it is preferred therefore to use as solvent the low-priced aliphatic hydrocarbons or mixtures thereof, as marketed by the petrochemical industry. If an aliphatic hydrocarbon is used as solvent, the solvent may yet contain minor quantities of aromatic hydrocarbon, for instance toluene. Thus, if for instance methyl aluminoxane (MAO) is used as co- catalyst, toluene can be used as solvent for the MAO in order to supply the MAO in dissolved form to the polymerization reactor. Drying or purification is desirable if such solvents are used; this can be done without problems by the average person skilled in the art.

A suspension polymerization is preferably carried out at temperatures between -100°C and + 250°C; The polymer solution or suspension resulting from the polymerization can be worked up by a method known per se. In general the catalyst is de-activated at some point during the processing of the polymer. The de-activation is also effected in a manner known per se, e.g. by means of water or an alcohol. Removal of the catalyst residues can mostly be omitted because the quantity of catalyst in the polymer, in particular the content of halogen and transition metal is very low according to the invention.

Polymerization can be effected at atmospheric pressure, at sub-atmospheric pressure, or at elevated pressure of up to 500 MPa, continuously or discontinuously. Preferably, the polymerization is performed at pressures between 1 KPa and 10 MPa. Higher pressures can be applied if the polymerization is carried out in so-called high-pressure reactors. In such a high-pressure process the process according to the present invention can also be used with good results.

The polymerization can also be performed in several steps, in series as well as in parallel. If required, the catalyst composition, temperature, hydrogen concentration, pressure, residence time, etc. may be varied from step to step. In this way it is also possible to obtain products with a wide molecular weight distribution.

The invention also relates to a polymer containing cyclic olefins which can be obtained by means of the polymerization process according to the invention.

The invention will now be elucidated by means of the following non-restrictive examples.

All tests in which organometallic compounds were involved were carried out in an inert nitrogen atmosphere, using standard Schlenk equipment. A method for synthesis of (dimethylaminoethyl)-tetramethyl cyclopentadienyl was published by P. Jutzi et al., Synthesis 1993, 684.

TiCl₃, the esters used and the lithium reagents, 2- bromo-2-butene and 1-chlorocyclohexene were obtained from Aldrich Chemical Company. TiCl₃.3THF was obtained by heating TiCl₃ for 24 hours in THF with reflux. (THF stands for tetrahydrofurane) . In the following 'Me' means 'methyl', 'iPr' means 'isopropyl, 'Bu' means

'butyl', 'iBu' means 'isobutyl', 'tertBu' means 'tertiary butyl' 'Ind' means 'indenyl', 'Flu' means

'fluorenyl', 'Ph' means 'phenyl'. Pressures mentioned are absolute pressures. GPC = gel permeation chromatography = SEC-DV.

Example I

Polymerisation of norbornene using

(dibutylaminoethyl)- tetramethylcyclopentadienyltitanium(III) dichloride

( C₅Me₄ ( CH₂ ) ₂NBu₂TiCl₂ ) as catalyst .

Synthesis of the catalyst a. Preparation of ethyl 3-(N,N-di-n- butylamino)propionate

Ethyl 3-bromopropionate (18.0 g; 0.10 mol) was added carefully to di-n-butylamine (25.8 g; 0.20 mol), followed by stirring for 2 hours. Then diethyl ether (200 ml) and pentane (200 ml) were added. The precipitate was filtered off, the filtrate was evaporated and the residue was distilled at sub- atmospheric pressure. The yield was 7.0 g (31%).

b. Preparation of bis(2-butenyl) (di-n-butylaminoethyl)- methanol

2-Lithium-2-butene was prepared from 2-bromo- 2-butene (16.5 g; 0.122 mol) and lithium (2.8 g; 0.4 mol) as in example I. To this, the ester of a) (7.0 g; 0.031 mol) was added with reflux in approx. 5 minutes, followed by stirring for about 30 minutes. Then was (200 ml) was carefully added dropwise. The water layer was separated off and extracted twice with 50 ml of CH₂C1₂. The combined organic layer was washed once with 50 ml of water, dried with K₂C0₃, filtered and evaporated. The yield was 9.0 g (100%).

c. Preparation of (di-n-butylaminoethyl )tetramethyl- cvclopentadiene) 4.5 g (0.015 mol) of the compound of b) was added dropwise to 40 ml of concentrated sulphuric acid of 0°C, followed by stirring for another 30 minutes at 0°C. Then the reaction mixture was poured out in a mixture of 400 ml of water and 200 ml of hexane. The mixture was made alkaline with NaOH (60 g) while being cooled in an ice bath. The water layer was separated off and extracted with hexane. The combined hexane layer was dried with K₂C0₃, filtered and evaporated. The residue was distilled at sub-atmospheric pressure. The yield was 2.3 g (55%).

d. Preparation of (di-n- butylaminoethyl)tetramethylcyclo¬ pentadienyltitanium(III)diehloride 1.0 equivalent of n-BuLi (0.75 ml; 1.6 M) was added (after cooling to -60°C) to a solution of the C_sMe₄H(CH₂)₂NBu₂ of c) (0.332 g; 1.20 mmol) in THF (50 ml), after which the cooling bath was removed. After warming to room temperature the solution was cooled to -100°C and then TiCl₃.3THF (0.45 g; 1.20 mmol) was added in a single portion. After stirring for 2 hours at room temperature the THF was removed at sub- atmospheric pressure.

After addition of special boiling point gasoline the complex (a green solid) was purified by repeated washing of the solid, followed by filtration and backdistillation of the solvent. It was also possible to obtain the pure complex through sublimation.

e. Polymerisation of norbornene The polymeristion of norbornene was performed at 35°C using the transition metal complex of example I d. Therefore 35 g norbornene were introduced into a three neck vessel containing toluene as a solvent. Then methylaluminoxane (Witco, 10% in toluene) was added to this reaction mixture, followed by the required amount of transition metal complex. The Al/Ti-ratio in the reaction mixture was 2000. After 66 minutes the polymerisation was stopped by the addition of methanol to the reaction mixture and the polymer slurry was washed with, respectively, 10% HCl in water, several portions of water, a saturated solution of NaHC0₃, followed by rinsing of the polymer with water and drying. The polymer formed was studied by wide angle X-ray scattering (WAXS) and solid state NMR and appeared to be polynorbornene having a very high melting temperature (T_mβlt around 600 C).

Example II Co-polymerisation of ethene and norbornene using (dibutylaminoethyl)- tetramethylcyclopentadienyltitanium(III) dichloride (C₅Me₄(CH₂)₂NBu₂TiCl₂) as catalyst.

With the transition metal complex mentioned in example I, a copolymerisation reaction was performed with ethylene and norbornene.

Therefore 600 ml of a dry alkane solvent (pentamethylheptane, PMH) was introduced under a nitrogen blanket into a stainless steel reactor with a reactor volume of 1.5 liters. 40 g norbornene was introduced into the reactor, the temperature of the reaction mixture was increased to 80° C and ethylene was introduced to an ethyle pressure of 600 kPa. In a catalyst dosing vessel with a content of 100 ml, 25 ml of an alkane solvent (PMH) was introduced, followed by the transition metal complex of example Id and the cocatalyst MAO (methylaluminoxane, Witco, 10% in toluene). The Al/Ti-ratio used was 2000. After 1 minute, this mixture was introduced into the reactor. The polymerisation was performed during 30 minutes, the polymer was removed from the reactor and washed and dried as described in example Ie. The copolymer was studied with DSC and was found to show a glass transition temperature (Tg) of -5 C.

Example III

Co-polymerisation of ethene and norbornene using

(dibutylaminoethyl)- tetramethylcyclopentadienyltitanium(III) dichloride

(C₅Me₄(CH₂)₂NBu₂TiCl₂) as catalyst at a lower temperature.

A copolymerisation was performed as described in example II, but at 30°C and with the use of MAO as a scavenger (Al/Ti=600), with 16 g norbornene and at an Al/Ti-ratio of 2000.

The copolymer yield was 16.2 kg copolymer/gTi*hour . The copolymer showed a glass transition temperature (Tg) of 148.6°C in the DSC spectrum.

Comparative example

Co-polymerisation of ethene and norbornene using a catalyst according to the state of the art.

A copolymerisation was performed as described in example III, but with the transition metal complex

Isopropylene-(9-fluorenyl)-cyclopentadienyl zirconium dichloride (prepared according to literature : J. Am. Soc. 110 (1988) 6255) and with Al/Zr-ratio 2000. The polymer produced, at a yield of 14.0 kg copolymer/gZr*hour , showed a weak glass transition temperature in the DSC spectrum at 145.6°C.

Example IV

Co-polymerisation of ethene and cyclopentene using (dibutylaminoethyl)- tetramethylcyclopentadienyltitanium(III) dichloride (C₅Me₄(CH₂)₂NBu₂TiCl₂) as catalyst.

An ethylene/cyclopentene copolymerisation reaction was performed in an experimental set-up as described in example I. Ethene was bubbled through the reaction mixture at an ethene pressure just above 1 bar (101 kPa).

19 g cyclopentene was introduced into the solvent followed by the cocatalyst methylaluminoxane and finally followed by the transition metal complex as described in example Id. The polymerisation was stopped after 60 minutes, the polymer was treated as described in example I and the polymer was analysed by ^Η-NMR. The cyclopentene content in the copolymer was determined to be 9% on a molar basis. It was determined by ¹³C-NMR that no ring opening of the cyclopentene had occurred.

Example V

Co-polymerisation of ethene and norbornene using (dimethylaminoethyl )tetramethylcyclopentadienyltitanium (IΙI)-dichloride (C₅Me₄(CH₂)₂NMe₂TiCl₂) as catalyst.

Synthesis of the catalyst a. Preparation of 4-hydroxy-4-(dimethylamino-ethyl )- 3 ,5-dimethyl-2 ,5-heptadiene 2-bromo-2-butene (108 g; 0.800 mol) was added to 10.0 g of lithium (1.43 mol) in diethyl ether (300 ml) in about 30 minutes with reflux. After stirring overnight (17 hours), ethyl-3-(N,N- dimethylamino)propionate (52.0 g; 0.359 mol) was added to the reaction mixture in about 15 minutes. After stirring for 30 minutes at room temperature 200 ml of water was added dropwise. After separation the water phase was extracted two times with 50 ml of CH₂C1₂. The organic phase was reduced by evaporation and the residue was distilled at reduced pressure. The yield was 51.0 g (67%).

b. Preparation of (dimethylaminoethylRetramethyl- cvclopentadiene

The compound (21.1 g; 0.10 mol) prepared as described under a) was added in a single portion to p- toluenesulphonic acid.H₂0 (28.5 g; 0.15 mol), dissolved in 200 ml of diethyl ether. After stirring for 30 minutes at room temperature the reaction mixture was poured out in a solution of 50 g of Na₂CO₃.10H₂O in 250 ml of water. After separation the water phase was extracted two times with 100 ml of diethyl ether. The combined ether layer was dried (Na₂S0₄), filtered and evaporated. Then the residue was distilled at reduced pressure. The yield was 11.6 g (60%).

c. Preparation of (dimethylaminoethyl)tetramethyl¬ cyclopentadienyltitanium(III)diehloride

1.0 equivalent of n-BuLi (1.43 ml; 1.6 M) was added (after cooling to -60°C) to a solution of the C₅Me₄H(CH₂)₂NMe₂ of b) (0.442 g; 2.29 mmol) in THF (50 ml), after which the cooling bath was removed. After warming to room temperature the solution was cooled to -100°C and then TiCl₃.3THF (0.85 g; 2.3 mmol) was added in a single portion. After stirring for 2 hours at room temperature the THF was removed at reduced pressure. After addition of special boiling point gasoline the complex (a green solid) was purified by repeated washing of the solid, followed by filtration and backdistillation of the solvent. It was also possible to obtain the pure complex through sublimation.

d. Copolymerisation of norbornene and ethylene An experiment was performed as described in example II. 100 ml of a toluene solution of 71.4 grammes of dry norbornene per 100 ml was added to the reactor that had been filled with pentamethylheptane. 0.1 mol MAO (on Al-basis, Witco, 10% in toluene) and 5*10^"5 mol of the reduced transition metal complex of example Vc were pre-mixed during 1 minute in a catalyst dosing vessel in 100 ml PMH. The temperature of the reactor was brought to 80° C and the ethylene pressure was equilibrated at 6 bar (608 kPa). Immediately after the 1 minute of mixing, the transition metal complex/MAO mixture was introduced into the reactor, starting the polymerisation reaction. A very rapid poly-merisation, that was stopped after 10 minutes, resulted in the production of 45.4 g copolymer, indicating a copolymer yield of 114 kg/gTi*hour. No polymer washing step was performed. The copolymer was analysed by DSC and showed a Tg at 45.3°C. The copolymer was a clear product. GPC results (conventional calibration) indicated a molecular weight distribution of 7.3, Mn^* = 1200 g/mol and MW^* = 9 kg/mol.

Example VI

Co-polymerisation of ethene and norbornene using a lower amount of

(dimethylaminoethyl )tetramethylcyclopentadienyltitanium (IΙI)-dichloride (C₅Me₄(CH₂)₂NMe₂TiCl₂) as catalyst.

An experiment was performed as described in example V but with only 2^*10^"5 moles of the reduced transition complex in combination with 0.04 mol MAO (on Al-basis). The reaction temperature was 50°C, the polymerisation time 30 minutes and the copolymer yield 20.9 kg/gTi*hour.

The copolymer was analysed with DSC and showed a Tg at 39.6°C. GPC results (conventional calibration) indicated a molecular weight distribution of 6.5, a number averaged molecular weight Mn^* of 14 kg/mol and Mw^* of 88 kg/mol.

Example VII

The synthesis of [1,2,4-triisopropyl-3- (dimethylaminoethylJcyclopentadienyl]- titanium(III)dimethyl

1. Reaction of cyclopentadiene with isopropyl bromide

Aqueous KOH (50%; 1950g, ca. 31.5 mol in 2.483 1 water) and Adogen 464 (31.5g) were placed in a 3L three-neck flask fitted with a condenser, mechanical stirrer, heating mantle, thermometer, and an inlet adapter.

Freshly cracked cyclopentadiene (55.3g, 0.79 mol) and isopropyl bromide (364 g, 2.94 mol) were added and stirring was begun. The mixture turned brown and became warm (50 °C). The mixture was stirred vigorously over night, after which the upper layer containing the product was removed. Water was added to this layer and the product was extracted with hexane. The combined hexane layer was washed once with water and once with brine, and after drying (MgS0₄) the solvent was evaporated, leaving a yellow-brown oil. GC and GC-MS analysis showed the product mixture to consist of diisopropylcyclopentadien (iPr₂-Cp, 40%) and triisopropylcyclopentadien (iPr₃-Cp, 60%). iPr₂-Cp and iPr₃-Cp were isolated by distillation at reduced (20 mmHg) pressure. Yield depending on distillation accuracy (approx. 0.2 mol iPr₂-Cp (25%) and 0.3 mol iPr₃-Cp (40%)). 2 . Reaction of lithium 1 , 2 , 4- triisopropylcyclopentadienyl with dimethylaminoethyl chloride

In a dry 500 ml flask under dry nitrogen, containing a magnetic stirrer, a solution of 62.5 mL of n- butyllithium (1.6 M in n-hexane; 100 mmol) was added to a solution of 19.2 g (100 mmol) of iPr₃-Cp in 250 mL of THF at -60 °C. The solution was allowed to warm to room temperature after which the solution was stirred over night. After cooling to -60 °C, dimethylaminoethyl chloride (11.3g, 105 mmol, freed from HCl (by the method of Rees W.S. Jr. & Dippel K.A. in OPPI BRIEFS vol 24, No 5, 1992) was added via a dropping funnel in 5 minutes. The solution was allowed to warm to RT after which it was stirred over night. The progress of the reaction was monitored by GC. After addition of water and an alkane mixture, the organic layer was separated, dried and evaporated under reduced pressure. Next to starting material iPr₃-Cp (30%), 5 isomers of the product (dimethylaminoethyl)triisopropylcyclopentadien (LH; 70%) are visible in GC . Two isomers are geminal (together 30%). Removal of the geminal isomers was feasible by precipitation of the potassium salt of the iPr₃-Cp anion and filtration and washing with an alkane mixture (3x). Overall yield (relative to iPr₃-Cp) was 30 mmol (30%) .

3. Applied reaction sequence to [1,2,4-triisopropyl-3- (dimethylaminoethyl)- cyclopentadenyl]titanium(III)dimethyl

Solid TiCl₃-3THF (18.53g, 50.0 mmol) was added to a solution of of K iPr₃-Cp in 160 mL of THF at -60 °C at once, after which the solution was allowed to warm to RT. The color changed from blue to green. After all the TiCl₃.3THF had disappeared the reaction mixture was cooled again to -60 °C after which 2.0 equivalents of MeLi (62.5 ml of a 1.6 M solution in Et₂0) were added. After warming to RT again, the black solution was stirred for an additional 30 minutes after which the THF was removed at reduced pressure.

c. Polymerisation

For the synthesis of an ethene/norbornene copolymer with a broad molecular weight distribution, allowing easy processing, a polymerisation experiment was performed as described in example VI, using 60.7 g norbornene, a temperature of 80°C and a polymerisation time of 10 minutes. The reduced transition metal complex was the compound of example VIIc; the Al/Ti- ratio was 2000.

The copolymer yield was 65 kg/gTi*hour. The copolymer was analysed by DSC. Interesting was the finding of two Tg's in the DSC curve : one at about 15 C and one at about 70°C. This "bimodal" character was also found in the GPC analysis of the copolymer, using universal calibration. These results showed a bimodal molecular weight distribution with Mn^* = 6000g/mol, Mw^* = 190 kg/mol, Mz^* - 850 kg/mol and an MWD (Mw^*/Mn^*) of 33. The expressions "conventional calibration" and "universal calibration" used in examples V to VII above in respect of GPC analysis, refer to the following calibration procedures: Universal Calibration procedure The universal calibration (log [h]*M vs Ve) is performed using polyethylene standards having a linear structure in the molar mass range 400-4000000 g/mol. Conventional Calibration procedure The convention calibration (log M vs Ve) is performed using polyethylene standards having a linear structure in the molar mass range 400-4000000 g/mol. Table 1 Examples of transition metal complexes according to the invention (see formulas I and VI)

10 ωω

15

Claims

C L A I M S

1. A process for the production of polymers containing cyclic olefins by contacting, under polymerisation conditions, at least one cyclic and/or polycyclic olefin, optionally in the presence of α-olefins, in the presence of a catalyst comprising a reduced transition metal complex and a co-catalyst, wherein said reduced transition metal complex has the following structure:

X

I M - L₂

I K_m

wherein: M is a reduced transition metal selected from group 4, 5 or 6 of the Periodic Table of the Elements ; X is a multidentate monoanionic ligand represented by the formula (Ar-R_t-)_SY(-R_t- DR'„)_q ^;

Y is a member selected from the group consisting of a cyclopentadienyl, amido (-NR'-), and phosphido (-PR'-) group; R is at least one member selected from the group consisting of (i) a connecting group between the Y group and the DR'_n group and (ii) a connecting group between the Y group and the Ar group, wherein when the ligand X contains more than one R group, the R groups can be identical as or different from each other ; D is an electron-donating hetero atom selected from group 15 or 16 of the Periodic Table of Elements; R' is a substituent selected from the group consisting of a hydrogen, hydrocarbon radical and hetero atom-containing moiety, except that R' cannot be hydrogen when R' is directly bonded to the electron-donating hetero atom D, wherein when the multidentate monoanionic ligand X contains more than one substituent R', the substituents R' can be identical or different from each other;

Ar is an electron-donating aryl group; L is a monoanionic ligand bonded to the reduced transition metal M, wherein the monoanionic ligand L is not a ligand comprising a cyclopentadienyl, amido (-NR'-), or phosphido

(-PR'-) group, and wherein the monoanionic ligands L can be identical or different from each other ; K is a neutral or anionic ligand bonded to the reduced transition metal M, wherein when the transition metal complex contains more than one ligand K, the ligands K can be identical or different from each other; m is the number of K ligands, wherein when the K ligand is an anionic ligand m is 0 for M³⁺, m is 1 for M⁴⁺, and m is 2 for M⁵⁺, and when K is a neutral ligand m increases by one for each neutral K ligand; n is the number of the R' groups bonded to the electron-donating hetero atom D, wherein when

D is selected from group 15 of the Periodic Table of Elements n is 2 , and when D is selected from group 16 of the Periodic Table of Elements n is 1; q and s are the number of (-R_t-DR'_n) groups and (Ar-R_t-) groups bonded to group Y, respectively, wherein q + s is an integer not less than 1; and t is the number of R groups connecting each of (i) the Y and Ar groups and (ii) the Y and DR'_n groups, wherein t is selected independently as 0 or 1.

2. A process according to claim 1, wherein the Y group is a cyclopentadienyl group.

3. A process according to claim 2, wherein the cyclopentadienyl group is an unsubstituted or substituted indenyl, benzoindenyl, or fluorenyl group.

4. A process according to claim 2, wherein said reduced transition metal complex has the following structure:

Y - R - DR'_n

I M(III) - L₂,

I K_m

wherein:

M(III) is a transition metal from group 4 of the Periodic Table of the Elements in oxidation state 3+.

5. A process according to claim 2, wherein said reduced transition metal is titanium.

6. A process according to claim 2, wherein said electron-donating hetero atom D is nitrogen.

7. A process according to claim 2, wherein the R' group in the DR'„ group is an n-alkyl group.

8. A process according to claim 2, wherein said R group has the following structure:

(-CR'₂-)_p,

wherein p is 1, 2, 3, or 4

9 . A process according to claim 2, wherein said monoanionic ligand L is selected from the group consisting of a halide, an alkyl group, and a benzyl group.

10. A process according to claim 2, wherein the Y group is a di-, tri- or tetraalkyl- cyclopentadienyl.

11. A process according to claim 2, wherein said co¬ catalyst comprises a linear or cyclic aluminoxane or a triaryl borane or tetraaryl borate.

12. A process according to claim 2, wherein at least one member selected from the group consisting of said reduced transition metal complex and said co¬ catalyst is supported on at least one carrier.

13. Process according to any one of claims 1-12, characterized in that at least one cyclic define is chosen from the group comprising: cyclobutene, cyclopentene, cyclohexene, cycloheptene, cyclooctene.

14. Process according to any one of claims 1-12, characterised in that at least one polycyclic olefin is chosen from the group comprising: norbornene, dimethano-octahydronaphtalene (DMON) , substituted norbornene.

15. Process according to any one of claims 1-12, characterized in that at least one cyclic olefine is cyclopentene.

16. Process according to any one of claims 1-12, characterized in that at least one polycyclic olefine is chosen from dimethano octahydronapthalene (DMON) and norbornene.

17. Process according to any one of claims 1-16, characterised in that at least one α-olefin is chosen from the group comprising ethene, propene, butene, pentene, hexene, heptene, octene and styrene (substituted or non-substituted) or mixtures thereof.

18. Polymer to be obtained by a process according to any one of claims 1-17.

19. Articles formed from a polymer according to claim 18.

20. Polymer blend, containing a polymer containing cyclic olefins obtained by a process according to any one of claims 1-17.