EP0896596A1

EP0896596A1 - Process for the production of functional polyolefins

Info

Publication number: EP0896596A1
Application number: EP97918423A
Authority: EP
Inventors: Maurits Frederik Hendrik Van Tol; Johannes Antonius Maria Van Beek; Paulus Johannes Jacobus Pieters
Original assignee: DSM NV
Current assignee: Koninklijke DSM NV
Priority date: 1996-05-03
Filing date: 1997-05-01
Publication date: 1999-02-17
Also published as: JP2000513761A; AU2653097A; WO1997042236A1

Abstract

The present process produces functionalized polyolefins by copolymerizing at least one polar monomer and at least one olefin under effective copolymerization conditions using a catalyst system containing a transition metal complex and a cocatalyst. The at least one olefin can be the predominate monomer forming the functionalized polyolefin chain. The transition metal complex includes a transition metal having a reduced valency which is selectable from groups 4-6 of the Periodic Table of the Elements, with a multidentate monoanionic ligand and with two monoanionic ligands. A polar monomer has at least one polar group and that group is reacted with or coordinated to a protecting compound prior to the copolymerization step. In particular, the reduced valency transition metal is titanium (Ti(III)).

Description

PROCESS FOR THE PRODUCTION OF FUNCTIONAL POLYOLEFINS

BACKGROUND OF THE INVENTION

1. Field of the Invention The present invention relates to a process for the production of functionalized polyolefins, and particularly of polyolefins which have polar functional groups incorporated in the polymer chain (backbone). These functionalized polyolefins are desirable for their chemical and physical properties such as good adhesion, dyeability, compatibility, permeability and paintability.

2. Description of Related Art In recent years several reports have been published describing the synthesis of functional polyolefins using both conventional Ziegler-Natta catalysts and metallocene catalysts.

The direct polymerization of heteroatom- containing functional monomers by conventional Ziegler- Natta processes is difficult because these catalysts are easily poisoned due to the formation of coordination complexes between the active polymerization site and the non-bonded electrons of the heteroatoms present in the functional monomers. Methods heretofore applied for the incorporation of polar monomers in polyolefin chains are summarized in Lofgren and Aaltonen, Proceedings Metallocenes '95, Houston, pages 333-343 (May 1995), the complete disclosure of which is incorporated herein by reference. These methods include isolation of the double bond from the heteroatom in the monomer by a spacer group, increasing the steric hindrance around the heteroatom or decreasing of the electron donating character of the heteroatom via attachment of electron withdrawing substituents on or adjacent to it. A method for allowing the direct copolymerization of an olefin and a polar comonomer with a soluble catalyst system composed of a metallocene component with methylaluminoxane is also presented in the article. The particularly proposed metallocene compounds are (n-butylCp)₂ZrCl₂,

Et(Indenyl)₂ZrCl₂ and Et(Indenyl)₂HfCl₂. This latter proposed method presents, however, a number of disadvantages of which include high Al/(transition metal)-ratios (4000), insufficient (low) catalytic activity. The alcohol incorporation was 1.1 mole % for 5-hexen-l-ol.

Despite these and other recent proposals, a need still remains for a process which enables directly incorporating polar monomers, into an olefinic-type polymer, while avoiding the heretofore encountered disadvantages, including a reguired high Al/transition metal ratio and excessive catalyst deactivation.

SUMMARY OF THE INVENTION It is, therefore an object of the present invention to solve the aforementioned problems, and enable incorporation of polar monomers directly into the polymer backbone during the preparation of a polyolefinic polymer. The present process enables directly incorporating polar monomers in a polyolefin chain without the need for an increased use of (methyl)aluminoxane ("MAO") as cocatalyst.

The present process enables directly incorporating functional monomers in a polyolefin chain using catalyst systems activatable by other non-MAO cocatalysts, such as, for instance, boranes and borates.

The present process does not suffer from excessive catalyst deactivation.

The present process can also be used to introduce a very broad range of polar monomers into a polyolefin chain.

The present process concerns the production of functional polyolefins by copolymerizing at least one polar monomer, and, as the predominant monomer, at least one α-olefin under effective copolymerization conditions using a catalyst system and a cocatalyst. In the present process functional polyolefins result from incorporating polar monomers into a polyolefin chain by copolymerization, using a catalyst system of a transition metal complex and a cocatalyst and in that the polar group(s) to be incorporated is (are) reacted with or coordinated to a protecting compound. 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

I K„

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-)_βY(-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 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 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.

BRIEF DESCRIPTION OF THE DRAWINGS 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.

DETAILED DESCRIPTION OF THE INVENTION

The present process concerns the production of functionalized polyolefins by copolymerizing at least one polar monomer and, as a main monomer, at least one α-olefin, under effective copolymerization conditions, using a catalyst system of a transition metal complex and a cocatalyst. The transition metal complex consists of a transition metal having a reduced valency which can be selected from groups 4-6 of the Periodic Table of the Elements (see IUPAC notation on the inside cover of the Handbook of Chemistry and

Physics, 7th Edition, 1989/1990), with a multidentate monoanionic ligand and with two monoanionic ligands. According to the process, a polar monomer has at least one polar group and that group is reacted with or coordinated to a protecting compound prior to the copolymerization step. In particular, the reduced valency transition metal is titanium (Ti (III)).

The term functionalized polyolefin (sometimes referred to herein a s a funtionalized polymer) means a polyolefin comprising at least one polar group. The polar group(s) comprised in the functionalized polyolefin can still be protected with a protecting compound.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

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__!-R_t-DR'_n 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 R-DR

It is noted that, generally, the transition metal group M is bonded to the Cp group via an h_, ^s 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 analo group:

Indene

The Y gro mido (-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'₂-)_p (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'„ 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'₅), 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 ή¹ to Y\⁶.

(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 Cj_-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 f or 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'_S), 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 ( I I I ) - 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 of the invention the polar group of the polar comonomer is protected by reaction with or coordination to a suitable protecting compound. Methods to sterically and/or chemically protect polar groups to be incorporated into polymers are generally available to a person skilled in the art.

In accordance with the invention the polar group to be incorporated in the polyolefin is preferably protected by an organoaluminum compound, an organo zinc compound or an organo magnesium compound. By preference, the protection is effected using an organoaluminum compound. Suitable organoaluminum compounds include alkyl aluminum compounds, alkyl aluminum hydrides, alkylalkoxy aluminum compounds, halogen-containing organoaluminum compounds like alkyl aluminum halides, aryl aluminum halides; aryl aluminum compounds, aluminoxanes (preferably methyl aluminoxane) , modified aluminoxanes, modified aluminum alkyls and related compounds that can be chosen by those skilled in the art. The aluminum alkyls are the most preferred compounds to react with or coordinate to the polar compounds to be incorporated in the polyolefin chain. Preferably, trimethylaluminum, triethylaluminum and triisobutylaluminum are used as a protecting compound.

Before the polar monomer is contacted with the catalyst system, the polar monomer is contacted, e.g., reacted or coordinated, with the protecting chemical compound. The contacting of the polar monomer with the protecting the chemical compound should be done with great care, especially in those cases were gas evolution or heat evolution can occur. The contacting is preferably performed at low temperature and/or in diluted solutions. Most preferably the contacting is performed under very controlled conditions at or below 50°C, under rapid stirring and under conditions where the gases that might be formed are allowed to escape from the reaction system without excessive pressure build-up in the reactor system equipment. A person skilled in the art can, however, elect to perform the contacting treatment at temperatures greater than 50°C, if required.

In the process of the present invention the copolymerization of the at least one olefin monomer (s) and the at least one polar monomer is carried out under effective copolymerization conditions using a catalytically effective anionic of the described catalyst composition, Suitable polar monomers copolymerizable with olefinic compounds, alpha-olefins, dienes and the like, are selectable from the class of monomers having the general formula:

H

I

H₂C = C-R (XI)

in which R is the polar group. The polar group is a group containing next to, or instead of carbon atoms at least one hetero atom from group 15-17 of the Periodic System of the Elements, the hetere atom can be directly bonded to the

H₂C=C-group

I H or it can be bonded to this group via a spacer group.

The spacer group is, for instance, an alkylene group, R can be selected from for instance, primary, secondary or tertiary alcohol, amine or alkyl halide, aldehyde, α-ketone, ether, amide, imine, thiol, sulfide, disulfide, borane, borate, carboxylic acid, ester, acylhalide, nitrile, nitro- or nitroso-group imide, anhydride, isocyanate, urea, acrylate, sulfone, sulfonic acid, silane, chloro-, bromo- or iodo-silane, silanol, halogen-containing groups, azo-groups, thioether, and urethane, among others. Mixtures of these polar groups can also be used. Also monomers with more than one polar group can be used. These groups may also be of a different nature. The copolymerizable polar monomer represented by Formula XI may contain any polar group which may be protected in accordance with this invention. The persons skilled in the art will easily understand how to determine such polar groups. The main monomer for the polyolefin chain comprises at least one olefin which can be suitably selected from among α-olefin, internal olefin, cyclic olefin and di-olefin. Mixtures of these can also be used. In particular, the α-olefin, is preferably selected from among ethylene, propane, butene, pentene, hexene, heptene, octene and styrene. Mixtures of any of these may also be used. More preferably, the α-olefin is at least one from among ethylene, propylene, octene and propene. Most preferably, the α-olefin is at least one from among ethylene, octene, and styrene.

The process according to the invention can also be used to prepare functionalized amorphous or rubber-like copolymers based on ethylene and another α- olefin. Propylene is preferably used as the other α- olefin, so that a functionalized EPM rubber is formed. It is also quite possible to use a diene besides ethylene and the other α-olefin, so that a functionalized ethylene, α-olefin, diene monomer rubber (a so-called functionalized EADM rubber) is formed. In particular, a functionalized ethylene propylene diene rubber ("EPDM") is preferred. In this way functionalized rubbers can be prepared.

According to the present invention, the catalyst composition can be used as is, or optionally the catalyst can be supported. The supported catalysts are used mainly in gas phase and slurry processes. A suitable carrier, e.g., support, includes any known carrier material for catalysts, for instance Si0₂₍ (silica) A1₂0₃ (alumina) or MgCl₂ to provide a heterogeneus supported catalyst. These carriers can be used as such, or modified with, for example, by one or more of silanes, aluminum alkyls and/or aluminoxane compounds. The catalyst system used in accordance with the present invention can also be prepared by in-situ methods which are known to those skilled in the art. The process of the present invention will hereafter be elucidated with reference to a polyolefin preparation, which is a representative polymerization. For the preparation of other polymers on the basis of an olefin, a person skilled in the art is expressly referred to the multitude of publications on this subject. The preparation of a functional polyolefin involves copolymerizing of one or more polar olefins, including polar cyclic and vinyl aromatic olefin monomers, as described above, having 3-32 carbon atoms and with an olefin monomer and optionally one or more non-conjugated dienes.

The process of the present invention can be conducted as a gas phase polymerization (such as, in a fluidized bed reactor), a liquid phase polymerization, such as a solution or slurry/suspension polymerization, or solid phase powder polymerization. For a gas phase polymerization no solvents or dispersion media are required. For solution or slurry polymerization processes a solvent or a combination of solvents may be employed if desired. In general, the quantity of transition metal to be used in case of solution or suspension polymerization is such that its concentration in the dispersion agent amounts to IO"⁸ - IO^-3 mol/1, preferably IO^-7 - 10^-4 mol/1. 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 polymerization under slurry conditions, a suspension utilizing a perfluorinated hydrocarbon or similar liquid may in particular be used.

Also excess olefinic monomer may be used as the reaction medium (so-called bulk polymerization processes). Aromatic hydrocarbons such as, for instance, benzene and toluene, can be used, but because

polymerizable polar monomer by further reactions. This de-protecting step can be effected by treating the protected-functionalized copolymer with, for instance, an acid such as a suitable inorganic acid such as HCl. The present co-polymerization can be effected at atmospheric pressure, at sub-atmospheric pressure, or at an elevated pressure of up to 500 MPa, continuously or discontinuously. By preference, the polymerization is performed at pressures between about 1 KPa and 35 MPa. Higher pressures can be applied if the polymerization is carried out in so-called high- pressure reactors. The present process can yield good results when practiced using such high pressure reactors. The co-polymerization can also be performed in several steps, in series, or in parallel. If required, process parameters, such as, the catalyst composition, temperature, hydrogen concentration, pressure, residence time, or the like, may be varied from step to step. In this way it is also possible to obtain products with a wide molecular weight distribution.

The present invention also relates to a functionalized polymer which can be obtained by means of the co-polymerization process according to the invention.

EXAMPLES 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 under 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, the complete disclosure of which is incorporated herein by reference. 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 tetrahydrofuran). 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.

Example I

Copolymer izat ion of ethene with 5-hexen-l-ol us ing

Et ( Cp ( iPr ) ₃ ) NMe₂TiCl₂ as catalyst .

Synthesis of the catalyst

a. 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 3 1 three-neck flask fitted with a condenser, mechanical stirrer, heating mantle, thermometer, and an inlet adapter. Freshly cracked cyclopen-tadiene (55.3 g, 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 arid 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 diisopropyl-cyclopentadien (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%)).

b. Reaction of lithium 1,2,4-triisopropylcvclo- pentadienyl 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; lOOmmol) 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 (in approx. 1 hour) 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 room temperature after which it was stirred over night. The progress of the reaction was monitored by GC. After addition of water (and pet-ether), 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 pet-ether (3x). Overall yield (relative to iPr₃-Cp) was 30 mmol (30%).

c. Reaction sequence to ri,2 ,4-triisopropyl-3-

(dimethylaminoethyl )-cvclopentadenyl1titanium fill) dichloride.

Solid TiCl₃3THF (18.53g, 50.0 mmol) was added to a solution of the potassium salt of iPr₃-Cp in 160 ml of THF at-60°C at once, after which the solution was allowed to warm to room temperature. The color changed from blue to green. After all the TiCl₃.3THF had disappeared the reaction mixture was cooled again to - 60°C. After warming to room temperature again, the solution was stirred for an additional 30 minutes after which the THF was removed at reduced pressure.

d. Polymerization

In a 1.5 L stainless steel reactor pentamethylheptane (PMH) solvent was introduced, followed by 0.02 moles of triethylaluminum and 1.0 ml of 5-hexen-l-ol that had been dried beforehand. This reaction mixture was mixed for 15 minutes at 40°C under an ethylene pressure of 600 kPa. In a catalyst premixing vessel 0.09 mol (on Al-basis) methylaluminoxane (Witco, 10% in toluene) was introduced in 25 ml PMH that had been pre-dosed. Then 5*10^~smoles of the reduced transition metal complex of example Ic were added to this mixture in the premixing vessel (Al/Ti-ratio= 1800). The resulting mixture was stirred during one minute. the polymerization reaction was started by addition of the catalyst/cocatalyst mixture to the stainless steel reactor. The polymerization reaction was stopped by closing the ethylene supply. The resulting polymer slurry was drained from the reactor and the polymer was recovered. The polymerization activity was 167 kg copolymer produced per gramme Ti per hour (polymer yield 167 kg/gTi*hour) . The polymer was studied by SEC- DV using conventional calibration. Mw was found to be 10.7 kg/mol, Mn was found to amount to 1.7 kg/mol.

The hexenol content in the polymer chain was found with ^-NMR to be 5 wt.%.

Example II Copolymerization of ethene with 5-norbornene-

2-carboxaldehyde using Et(Cp(iPr)₃)NMe₂TiCl₂ as catalyst. Catalyst Synthesis

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 3 1 three-neck flask fitted with a condenser, mechanical stirrer, heating mantle, thermometer, and an inlet adapter. Freshly cracked cyclopen-tadiene (55.3 g, 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 diisopropyl-cyclopentadien (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%)).

Reaction of lithium 1,2,4-triisopropylcyclopentadienyl with dimethylaminoethyl chloride.

(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 pet-ether (3x). Overall yield (relative to iPr₃-Cp) was 30 mmol (30%).

Reaction sequence to T1,2 ,4-triisopropyl-3-

(dimethylaminoethyl )-cvclopentadenyl ltitanium (III) dichloride.

Copolymerization

Under the conditions described in example Id an experiment was performed using the functional monomer 5-norbornene-2-carboxaldehyde as the comonomer and using the same type and amount of catalyst and cocatalyst.

0.15 moles of triethylaluminum were added to the reactor, followed by 10 ml 5-norbornene-2- carboxaldehyde. The rest of the procedure followed was exactly the same as described in example I. The polymer yield was 228 kg copolymer/gTi*hour . The polymer was studied by SEC-DV using conventional calibration. Mw was found to be 26 kg/mol, Mn was found to be 3.7 kg/mol, and Mz was found to be 132 kg/mol. ^-H-NMR showed a comonomer content in the copolymer of 6.4 wt.%.

Comparative example 1

50 ml of dry toluene were added to a dry three neck vessel. Then 1 ml dried 5-hexene-l-ol was added followed by 0.01 moles of triethyl aluminum and 0.075 moles (on Al-basis) of methylaluminoxane (Witco, 10% in toluene). The ethylene pressure was equilibrated at 1.5 bar (150 kPa), the temperature was set at 40 C and the polymerization was started after 15 minutes of stirring by the addition of 5^*10^~5 moles of the transition metal complex isopropylene-(9-fluorenyl)- cyclopentadienyl zirconium dichloride (prepared according to literature : J. Am. Chem. Soc. 110 (1988) 6255), Al/Zr-ratio applied : 1500. After 60 minutes the polymerization reaction was stopped by the addition of methanol, the polymer was washed with HCl (10% in water), water, a saturated solution of NaHC0₃ in water, and finally several times with water and with acetone. The polymer was dried under vacuum at 70 C.

The polymer yield was 0,55 kg/gZr.hour. The polymer was studied by ^-NMR and DSC and was found to contain 4 mole % of hexenol, incorporated in the polymer chain. The OH-groups were clearly resolved. This percentage of 5-hexen-l-ol incorporated in the polymer chain shows the advantage of the method described in the present invention: it is almost 4 times as high as described so far in literature. The activity of this catalyst system in which the transition metal is in its highest formal oxidation state, is, however, low.

A few examples of transition metal complexes according to the invention are presented in Table 1. Table 1 Examples of transition metal complexes according to the invention (see formulas I and VI)

10 cu

15

Claims

WHAT IS CLAIMED IS:

1. A process for the production of functional polyolefins comprising the steps of: copolymerizing polar monomers and, as the main monomer, at least one olefin under effective copolymerization conditions 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

Km

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'_n)_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 M*⁺, 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'_n 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. A process according to claim 1, wherein the polar group of the polar comonomer is protected by reaction with or coordination to a protecting compound selected from the group consisting of organoaluminum compounds, organo zinc compounds and organo magnesium compounds.

14. A process according to claim 13, wherein the polar group of the polar comonomer is protected by reaction with or coordination to an organoaluminum compound.

15. A process according to claim 1, wherein the polar group of the polar comonomer is protected by reaction with or coordination to a protecting compound selected from the group consisting of alkyl aluminum compounds, alkyl aluminum hydrides, alkylalkoxy aluminum compounds, alkyl aluminum halides, aryl aluminum halides; aryl aluminum compounds, aluminoxanes, and a mixture of any thereof.

16. A process according to claim 15, wherein the polar group of the polar comonomer is protected by a compound selected from the group consisting of trimethylaluminum, triethylaluminum, triisobutylaluminum.

17. A process according to claim 1,wherein the polar monomer is at least one from the class of monomers represented by the formula:

H

H₂C = C-R wherein R is the polar group.

18. A process according to claim 17, wherein the polar group R can be selected from primary, secondary or tertiary alcohol, amine or alkyl halide, aldehyde, a ketone, ether, amide, imine, thiol, sulfide, disulfide, borane, borate, carboxylic acid, ester, acylhalide, nitrile, nitro- or nitroso-group imide, anhydride, isocyanate, urea, acrylate, sulfone, sulfonic acid, silane, chloro-, bromo- or iodo-silane, silanol, halogen-containing groups.

19. A process according to claim 1, wherein the main monomer of the polymer chain is at least one from the group consisting of ethylene, propylene, butene, pentene, hexene, heptene, octene and styrene.

20. A polymer to be obtained by a process according to claim 1.

21. A blend of polymers comprising at least two functionalized polyolefins obtained by a process according to claim 1.