HK1024004A - Bridged metallocene complex for the (co)polymerization of olefins - Google Patents

Description

Bridged metallocene complexes for the (co) polymerization of olefins

The present invention relates to a bridged metallocene complex useful for the (co) polymerization of olefins.

More particularly, the present invention relates to a bridged metallocene complex of a particular transition metal, and a catalyst comprising or derived from the complex, which catalyst is suitable for the polymerization or copolymerization of ethylene with other α -olefins, optionally together with a suitable cocatalyst, a process for preparing the metallocene complex and its corresponding ligand, and a process for polymerizing olefins therefrom.

It is generally known in the art that ethylene or alpha-olefins can be polymerized or copolymerized, usually at low, medium or high pressure, using transition metal based catalysts, which are known as ziegler-natta catalysts. A specific type of active catalyst in the polymerization of olefins consists of an organoxy derivative of aluminium (in particular polymeric methylaluminoxane or MAO) and eta of a transition metal of groups 3 to 6 of the periodic Table of the elements (published by IUPAC approved by "CRC Press INC., 1989)⁵-the combined composition of cyclopentadienyl derivatives (metallocenes). Particularly interesting results have been obtained for group 4 metallocene-based catalysts, for example, the more conventional form of the catalyst can be determined as in the following formula (I):(I) wherein M represents a group 4 metal; each R_AEach independently representing a group of anionic character, e.g. hydrogenatedHalides, phosphonate or sulfonate anions, alkyl or alkoxy, aryl or aryloxy, amide groups, silyl groups, and the like; "w" is an index which may be an integer of 1 or 2 depending on the valence of M being 3 or 4; cp represents eta⁵Ligands of cyclopentadienyl type, generally chosen from η⁵-a cyclopentadienyl group,⁵-indenyl r⁵-fluorenyl or substituted derivative thereof; r₈May have ligands Cp or R_ADefinition of one of the groups regardless of the nature of the other substituents. So-called "bridged" metallocenes have also proved to be of particular interest in the known art, in which two Cp groups, which are identical or different, are coordinated to the metal M and are covalently bonded to one another by means of divalent organic groups. For well-known methods of preparing the above compounds, reference is made to the description in h.sinn, w.kaminsky, adv.organomet.chen, volume 18(1980), page 99 and US4,542,199.

These catalysts generally have a high catalytic activity and a certain diversity when applied to the preparation of polyolefins having particular characteristics, in particular for the stereochemical control of the polymerization of alpha-olefins, such as propylene.

In particular, the introduction of a "bridging" group may result in two penta-coordinated rings (. eta.) of the cyclopentadienyl ligand⁵) Maintaining a more rigid accessible position than without the bridge. This improvement enables the preparation of polymers having particular characteristics which are sometimes not obtainable by the use of unbridged metallocenes, depending on the catalyst composition and the olefin to be polymerized.

It is well known that certain "bridged" metallocene catalysts are capable of carrying out the polymerization of alpha-olefins with high stereoregularity. Although the complex (Ind)₂ZrCl₂A polypropylene having a low isotacticity index is provided [ L.Resconi et al, Macromolecules 25, 6814-]However, the corresponding catalysts (racemic isomeric forms) with ethylene and dimethylsilyl bridges give polypropylene with 99% and 97% isotacticity, respectively, as described in, for example, DE3,743,321 and DE3,443,087.

In EP-A310,734, at least two of the above-mentioned complexes of the formula (I) are mixed with one another to give a polymer having a relatively high molecular weight distribution (MWD > 3), which is therefore easier to process in an extruder. "Makromolecular Chemie", Vol 194(1993), page 1745. sub.1755 describes loading on an inorganic matrix (Al)₂O₃，MgCl₂) The "bridged" complexes of (A) in place of MAO in trialkylaluminum AlR during the polymerization of propylene₃The use of cationic "bridged" complexes in EP-A418-044 in the presence of MAO is active in the polymerization even in the absence of MAO.

There is a great deal of patent and scientific literature on "bridged" catalysts. Most of the structures studied and claimed are preferably based on Zr and Hf and contain cyclopentadienyl (Cp), indenyl (Ind) or fluorenyl (Flu) rings as pentadentate ligands, optionally substituted in certain positions on the molecular skeleton by suitable groups. Thereby improving the properties of the catalyst and the resulting polymer. For example, W.Spaleck et al in "Angewandte Chemie, int.Ed.Eng." Vol.31 (1992), p.1347-1349 indicate that if the methyl substituent is placed in the 2-position of the indenyl ring, the catalyst Me₂Si(Ind)₂ZrCl₂It is possible to prepare polypropylene having a higher molecular weight, and the substitution of the naphthylmethyl group in the 4-position according to Organometallics, Vol.13 (1994), pp.954-963 also improves the polymer yield and the tacticity index.

Numerous other examples are cited in the patent literature, such as European patent applications EP-A582,194, EP-A537,130, EP-A574,370 and EP-A581,754.

Despite the many advantages of the prior art, represented by the so-called "classical" ziegler-natta catalysts, which have an intrinsic heterogeneous and multicenter nature, however, the metallocene-based catalysts also have various drawbacks, such as the fact that, in particular when using high temperature polymerization processes, the average molecular weight of the polymers prepared therefrom is still insufficient. Furthermore, also in the case of metallocenes, it is desirable to further increase the stereoselectivity of the polymerization of alpha-olefins when using high temperature and high pressure processes of about 150 ℃ and 250 ℃ and 50-100 MPa. It is also preferred to further increase the activity and polymerization rate imparted by the catalyst in a process characterized by a reduced residence time in the reactor.

Other unsatisfactory aspects of the above catalysts are their performance in the copolymerization of ethylene to prepare low density polyethylene or olefin elastomers, with which it is difficult to obtain copolymers having a sufficiently high molecular weight, which are suitable for many industrial fields. It is known in practice that large amounts of comonomers have to be incorporated into the copolymers in the desired amounts, but this results in an increase in the rate of chain transfer reactions which compete with the polymerization and in the formation of unsatisfactory molecular weights. This drawback becomes more pronounced when operating with high temperature polymerization processes, since in this process chain transfer reactions already become the predominant reaction in the absence of comonomers. In this case, the amount of monomer insertion, and the "means" of insertion to form the comonomer block sequences, are more important than a statistical distribution that is more desirable to obtain.

Despite the above disadvantages and the characteristics of the specific application, the prior art is replete with a variety of different types of substituted η⁵The cyclopentadienyl ligands have been studied in detail, but few publications have been published on the influence of groups which form "bridges" between these ligands, which are virtually essentially limited to the group-CH, on a polymerization process₂-CH₂-，-CMe₂-, and-Si (R)_CR_D)-(R_CAnd R_DIs an alkyl or aryl group).

The publication "Makromolekulare Chemie, Rapid Comm." Vol.14 (1993), page 633. sub.636 describes a bis (. eta.) -based⁵Cyclopentadienyl) complexes containing a bridge between two ligands consisting of 1, 3-phenylene-dimethylene. Although capable of polymerizing ethylene in the presence of MAO, these complexes have poor solubility in aromatic and/or aliphatic hydrocarbons, and are more reactive than comonomeric metallocene complexes such as (. eta.) (eta.)⁵-C₅H₅)₂ZrCl₂And lower.

The publication "Acta Chimica Sinica", Vol.48 (1990), p.298-301 describes the preparation of certain zirconium and titanium biscyclopentadienyl complexes which contain a phenylenedimethylene bridge between two cyclopentadienyl ligands. However, there is no mention in this publication that these complexes can be used for the polymerization of olefins.

EP-A752,428 in the Applicant's European patent application discloses bridged metallocene complexes in which two η⁵-cyclopentadienyl and a compound of formula-CH₂-(A)-CH₂The divalent radical of (a) wherein a is a divalent unsaturated hydrocarbon radical, although these complexes achieve reasonable reaction rates when forming olefin homopolymers and copolymers, the insertion capacity of the comonomers in the copolymerization with ethylene is still unsatisfactory.

The applicant has now found a new class of metallocene complex groups containing specific "bridging" groups, capable of catalyzing the (co) polymerization of α -olefins in the presence of suitable cocatalysts without the drawbacks mentioned above, and capable of obtaining polymers with high yields and high molecular weights.

Accordingly, a first object of the present invention relates to a metallocene complex having the following formula (II):(II) wherein: m represents a metal selected from titanium, zirconium or hafnium;

each A 'or A' independently represents an organic radical containing an anionic character eta coordinated to the metal M⁵-a cyclopentadienyl ring;

each R 'or R' independently represents a group of anionic character sigma-bonded to the metal M; preferably from hydrides, halides, C₁-C₂₀Alkyl or alkylaryl radicals, C₃-C₂₀Alkylsilyl group, C₅-C₂₀Cycloalkyl radical, C₆-C₂₀Aryl or arylalkyl, C₁-C₂₀Alkoxy or thioalkoxy radical, C₂-C₂₀Carboxylates or carbamates, C₂-C₂₀Dialkylamido and C₄-C₂₀An alkylsilylamide group;

b represents an unsaturated divalent organic residue having from 1 to 30 carbon atoms, which is bonded, by means of an unsaturated atom other than hydrogen, to the cyclopentadienyl ring and to the-CH group of the group A', respectively₂-on the methylene group.

A second object of the present invention relates to a process for the (co) polymerization of olefins which comprises polymerizing or copolymerizing ethylene and/or one or more alpha-olefins under suitable conditions of temperature and pressure, in a mixture (contact and reaction) of a metallocene complex as defined above with a suitable activator (or cocatalyst) selected from the compounds of the known art, in particular organometallic M's selected from boron, aluminum, gallium and tin, or mixtures thereof.

Other possible objects of the present invention will be apparent from the description and examples which follow.

The term "unsaturated atom" in the context of the present invention and claims refers to an atom of an organic or organometallic compound which is capable of forming with at least one other atom a double bond of olefinic or aromatic type.

In the complexes of the formula (II) having the catalyst of the invention, -B-CH₂The group bridging the two cyclopentadienyl groups A 'and A' gives the molecule a particular geometry, deriving from the intrinsic asymmetry of the "bridge", and the fact that this B group is bonded to the remainder of the structure of formula (II) by means of a bond adjacent to the unsaturated bond. This generally consists of a cyclic or acyclic unsaturated organic radical containing from 1 to 30 carbon atoms, which may also include one or more non-metallic heteroatoms comprising elements from groups 14 to 17 of the periodic Table of the elements, preferably from Si, N, O, S, P, Cl, Br and F, more preferably from Si, N, O and F. In a particular embodimentThe B group being a C group which is free of hetero atoms₂-C₂₀An unsaturated hydrocarbon group.

Such unsaturated B groups may be ethylenically unsaturated groups which are characterized by double bonds, such as-C ═ C-vinylene or heteroatom-containing-C ═ N-groups. Such ethylenically unsaturated groups may be bonded in the "Z" configuration to the groups-A' -and-CH of the complex of formula (II) with two atoms at the end of the double bond, respectively₂On the-A', e.g. in the form of the following bridging groupAndor it may comprise a single carbon atom bonded to both of the above groups, for example where the B group has the general formula:and

the group B according to the invention may also consist of phenylene, preferably ortho-phenylene, optionally substituted in any of the remaining positions of the ring. Typical substituents are those which match the complexes of the formula (II) used in the catalysis of the polymerization of olefins, i.e.which do not react with the cocatalyst described below. Examples of such substituents are halogen, such as fluorine, chlorine or bromine, C₁-C₁₀Alkyl radicals such as methyl, ethyl, butyl, isopropyl, isopentyl, octyl, benzyl, C₃-C₁₂Alkylsilyl groups, e.g. trimethylsilyl, triethylsilyl or tributylsilyl, cycloalkyl groups, e.g. cyclopentyl or cyclohexyl, C₆-C₁₀Aryl radicals such as phenyl or tolyl, C₁-C₈Alkoxy radicals such as methoxy, ethoxy, iso-or sec-butoxy, or radicals which form additional saturated or unsaturated fused rings with the main ring. Specific examples of phenylene B groups, but not limited thereto, are ortho-phenylene, 2, 5-dimethyl-ortho-phenylene, 3, 4-dimethyl-ortho-phenylene, 3-ethyl-ortho-phenylene, 3-octyl-ortho-phenylene, 3, 4-difluoro-ortho-phenylene, 2-formazanOxy-o-phenylene, m-phenylene, 4, 6-dimethyl-m-phenylene, 5-phenyl-m-phenylene, 1, 2-naphthylene, 2, 3-naphthylene, 1, 3-naphthylene, 2, 3-phenanthrylene, and the like.

A further classification of divalent B groups included within the scope of the present invention consists of fused aryl groups. Wherein two-A' -and-CH having the formula (II) are bonded₂The atoms of the group-A "-are in the" peri "position on two adjacent aromatic rings, and groups such as 1, 8-naphthylene, 4, 5-dimethyl-1, 8-naphthylene, 5, 6-acenaphthylene, etc., belong to this class.

According to the invention, R 'and R' of formula (II) each independently represent a group of anionic character sigma-bonded to the metal M. Typical examples of R 'and R' are hydrides, halides, preferably chlorides or bromides, linear or branched alkyl groups such as methyl, ethyl, butyl, isopropyl, isopentyl, octyl, decyl, benzyl, alkylsilyl groups such as trimethylsilyl, triethylsilyl or tributylsilyl, cycloalkyl groups such as cyclopentyl, cyclohexyl, 4-methylcyclohexyl, aryl groups such as phenyl or tolyl, alkoxy groups such as methoxy, ethoxy, iso-or sec-butoxy, ethylsulfide, carboxylate groups such as acetate, trifluoroacetate, propionate, butyrate, pivalate, stearate, benzoate or dialkylamide groups such as diethylamide, dibutylamide, or alkylsilylamide groups such as bis (trimethylsilyl) amide or ethyltrimethylsilamide. The two R 'and R' can also be chemically bonded to each other to form a ring having 4 to 7 atoms other than hydrogen, also including the metal M. Typical in this respect are divalent anionic groups such as trimethylene or tetramethylene or ethylenedioxy, particularly preferred R' and R "are chloride, methyl and ethyl, on the basis of their availability and the ease of preparation of the complexes containing them.

According to the invention, each A 'or A' group of formula (II) having anionic character contains eta coordinated to the metal M⁵-a cyclopentadienyl ring, usually by extraction of H^＋Ionic, from substituted or unsubstituted cyclopentanediylAn alkenyl molecule is obtained. Usually comprising two η⁵The molecular structure and typical electron and coordination configurations of cyclopentadienyl titanium, zirconium or hafnium metallocene complexes have been widely described in the literature and are well known to the person skilled in the art.

In a more general embodiment of the invention, when A 'and/or A' consist of a fused bicyclic group, such as indenyl or tetrahydroindenyl, the groups-B-CH in formula (II)₂The "bridge" may be bonded to any carbon atom, preferably the 1 or 3 position, of the cyclopentadienyl rings of the groups A' and A ", respectively, as long as the valency of the bond is possible.

Each A 'or A' group in the preferred complexes described above is typically represented by the following formula (III):(III) wherein each substituent R₁，R₂，R₃And R₄Independently represents hydrogen. Halogen, preferably F, Cl or Br, aliphatic or aromatic C₁-C₂₀Hydrocarbyl, optionally comprising one or more heteroatoms different from carbon and hydrogen, especially F, Cl, O, S and Si, or adjacent R₁，R₂，R₃And R₄Wherein at least any two substituents are linked to form a saturated or unsaturated C₄-C₂₀A cyclic structure comprising one bond of the cyclopentadienyl ring, which structure optionally contains one or more of the above heteroatoms.

Preferred groups A 'or A' contained in the above formula (III) are the well-known cyclopentadienyl, indenyl or fluorenyl groups, and their homologues, wherein one or more carbon atoms of the molecular skeleton (with or without the cyclopentadienyl ring) are substituted by, for example, halogen, preferably chlorine or bromine, linear or branched alkyl radicals such as methyl, ethyl, butyl, isopropyl, isopentyl, octyl, decyl, benzyl, alkylsilyl radicals such as trimethylsilyl, triethylsilyl or tributylsilyl, cycloalkyl radicals such as cyclopentyl, cyclohexyl, 4-methylcyclohexyl, aryl radicals such as phenyl or toluene, alkoxy or thioalkoxy radicals such as methoxy, ethoxy, iso-or sec-butoxy, thiolethyldialkylamide radicals such as diethylamide, dibutylamide, or an alkylsilylamide such as bis (trimethylsilyl) amide or ethyltrimethylsilyl amide. These A 'or A' groups may also include several fused aromatic rings, such as 4, 5-benzoindenyl. Particularly preferred A 'or A' groups are cyclopentadienyl, indenyl, 4,5, 6, 7-tetrahydroindenyl, fluorenyl and their corresponding methyl-substituted radicals.

Typical examples of complexes of formula (II) suitable for the purposes of the present invention are the following compounds, without this limiting the full scope of the invention. 1, 3-propenylene- (1-Ind)₂ZrCl₂(ii) a 1, 3-propenylene- (1-Ind)₂TiCl₂；1，8-Naphth-(1-Ind)₂ZrCl₂；1，8-Naphth-(1-Ind)₂Zr(NMe₂)₂(ii) a Ortho-benzylidene- [1 (3-methyl) Ind]₂HfCl₂(ii) a Ortho-benzylidene- (1-Ind)₂ZrCl₂(ii) a Ortho-benzylidene- (Flu)₂HfCl; ortho-benzylidene- (1-Ind)₂TiCl₂(ii) a Ortho-benzylidene- (Flu)₂ZrBz₂(ii) a Ortho-benzylidene- (C)₅H₄)₂Zr(OCOCMe₃)₂(ii) a Ortho-benzylidene- (1-Ind)₂Zr(OCO-CF₃)₂(ii) a Ortho-benzylidene- [ (5, 6-dimethyl) Ind]₂ZrCl₂(ii) a Ortho-benzylidene- [1- (4, 7-dimethyl) Ind]₂TiBr₂(ii) a Ortho-benzylidene- [1- (4, 7-diphenyl) Ind]₂ZrMe₂(ii) a O-benzylidene- [1- (4, 5, 6, 7-THInd)]₂TiCl₂(ii) a Ortho-benzylidene- [1- (3-methyl) Ind]₂TiCl₂(ii) a Ortho-benzylidene- [1- (3, 4, 7-trimethyl) Ind]₂ZrCl₂(ii) a Ortho-benzylidene- [3- (5, 1-dimethyl) Ind]₂ZrMe₂(ii) a (fluoro-o-benzylidene-Cp)^*)Ti(NMe₂)₂(ii) a Ortho-benzylidene- - [1- (4, 7-dimethyl) Ind]₂TiBz₂(ii) a Ortho-benzylidene- (1-Ind)₂Zr(OCO-n-C₃H₇)₂

The following abbreviations are used for the above formulae: 1, 8-Naphth ═ 1, 8-naphthylidene methylene, Me ═ methyl, Bz ═ benzyl, Ind ═ indenyl, Flu ═ fluorenyl, THInd ═ 4,5, 6, 7-tetrahydroindenyl, Cp ═ tetramethylcyclopentadienyl, methyl, ethyl, propyl, butyl,

the above-mentioned complexes of formula (II) can be efficiently prepared by a known process which is described in the literature for the preparation of "bridged" biscyclopentadienyl complexes of transition metals and which is significantly improved to prepare the desired complexes.

The most commonly used method involves the reaction of a salt of the metal M, preferably a chloride, with an alkali metal salt having the dianion of the biscyclopentadienyl ligand of the desired structure. In the more conventional case, such ligands have the general formula (IV):

HA″—CH₂B-A ' H (IV) in which A ', A "and B all have the general meanings given above for the complexes of the formula (II), with the obvious difference that in this case each cyclopentadienyl A ' or A" does not undergo eta formation with the metal M⁵-coordinated and not aromatic in nature, but a neutral group with adjacent hydrogen atoms as represented by formula (IV).

The above-mentioned groups-A' H and HA "-preferably have a structure which can be briefly represented by the following formula (IV-bis):(IV-bis) wherein: each substituent R₁，R₂，R₃And R₄Having the corresponding radical R as in formula (III)₁(i ═ 1, 2, 3, or 4) the same definitions and the same preferred ranges,

the hydrogen atom represented by the center of the ring is then bonded to any carbon atom of the cyclopentadienyl ring,

the dotted ring is briefly represented as two bi-conjugated bonds on the remaining 4 atoms of the cyclopentadienyl ring.

Generally, non-limiting examples of compounds of formula (IV) of the present invention are 1- (1-indenyl) -2- (1-indenyl) methylbenzene, 1- [1- (4, 5, 6, 7-tetrahydro) indenyl ] -2- [1- (4, 5, 6, 7-tetrahydro) indenyl ] methylbenzene, 1- (4, 7-dimethyl-1-indenyl) -2- (4, 7-dimethyl-1-indenyl) methylbenzene, 1- (cyclopentadienyl) -2- (cyclopentadienyl) methylbenzene, 1- (1-indenyl) -8- (1-indenyl) methylnaphthalene.

The preparation of the complexes of the formula (II) generally comprises two steps, the first step, of reacting the ligands of the formula (IV) with alkyllithium, such as methyllithium or butyllithium, or the corresponding magnesium derivatives, in an inert solvent, preferably consisting of an aromatic hydrocarbon or an ether, in particular tetrahydrofuran or diethyl ether. The temperature during the reaction is preferably kept below room temperature to avoid the occurrence of a second reaction, at the end of which the corresponding cyclopentadienyl dianionic lithium salt is obtained.

In a second step, the cyclopentadienyl dianion salt is reacted with a preferably chloride salt of the transition metal M, still in an inert organic solvent, preferably at a temperature below room temperature, which is generally from-50 to 0 ℃. At the end of the reaction, the complex of formula (II) thus obtained is isolated and purified using methods known from organometallic chemistry. As is well known to those skilled in the art, the presence of air is sensitive to the above operations and therefore the reaction must be carried out in an inert atmosphere, preferably nitrogen or argon.

Most of the methods described in the literature, whether general or specific, are substantially similar to the above-described methods, as described in publications D.J.Cardin "Chemistry of organic Zr and Hf compounds" J.Wlley and Sons Ed, New York (1986); halterman "Chemical Review", Vol. 92(1992) p. 965- & 994; duthaler and A.Hafner "Chemical Review", volume 92(1992) pages 807-832.

At the same time, the applicant has found an initial synthesis process for the preparation of a particular class of biscyclopentadienyl ligands comprised in formula (IV), in which the "bridge" B consisting of an ortho-phenylene group and a group a' is different from fluorene or substituted fluorene. This process, which forms another object of the invention, makes it possible to obtain the above ligands in satisfactory yields and with high purity, and also makes it easy to use those ligands in which the A 'and A' groups have different structures (asymmetry).

Another object of the present invention, as defined above, relates to a process for the preparation of a compound having the following formula (V):

HA″—CH₂-B '-A' H (V) wherein: each-a 'H or HA "-group independently represents a cyclopentadienyl group comprised in the preceding formula (IV-bis), with the proviso that a' H is different from fluorenyl or substituted fluorenyl, B represents a divalent organic group having 6 to 30 carbon atoms and comprising a phenyl aromatic ring, the two valencies of which are in adjacent positions (adjacent to each other) of the aromatic ring, characterized in that it comprises the following steps in sequence: a) having the formula HO-CH₂The alcohol radical of o-bromobenzyl alcohol of-B' -Br is reacted with an enol-alkyl ether R having 3 to 10 carbon atoms⁶-O-CR⁷＝CH₂For example 2-methoxypropene, in which B' is as defined above and R is⁶=C₁-C₆Alkyl radical, R⁷Hydrogen or C₁-C₆Alkyl, reacted in an aprotic Lewis acid, preferably POCl₃In the presence of a catalyst to form the corresponding gem-diether Br-B' -CH₂-O-CR⁷(CH₃)-O-R⁶(ii) a b) Metallation of the geminal diether obtained in step (a) with an alkyl compound of lithium or magnesium having 1 to 10 carbon atoms, such as butyllithium or diethylmagnesium, in a non-polar solvent at a temperature of 0 to 30 ℃ by substitution of the bromine atom, to obtain the corresponding lithium or magnesium salt (Li or Mg) -B' -CH₂-O-CR⁷(CH₃)-O-R⁶(ii) a c) The salt thus obtained is condensed with an-A' H precursor consisting of a cyclopentenone having the corresponding structure, wherein the carbonyl oxygen is at the carbon in the ring position which has to be bonded to the magnesium or lithium salt, such as 1-2, 3-dihydro-1-indanone or 2-2, 3-dihydro-1-indanone, the reaction is carried out in THF at a temperature of less than-30 ℃, preferably from-50 to-100 ℃, and the compound having the formula (V-bis) is then obtained by hydrolysis of the reaction product with removal of water:(V-bis) or the corresponding bicyclic helical derivative is preferably obtained by addition of an-OH group to the double bond alpha in B'; wherein the various symbols B', R₁，R₂，R₃And R₄All have the same definitions as above; d) reacting the compound of formula (V-bis) or the corresponding spiro derivative obtained in step (c) with an excess of aqueous hydrochloric or hydrobromic acid, preferably a high HBr solution (> 25 wt%), at a temperature of 50 to 130 ℃, preferably the reflux temperature of the mixture, to obtain an o-cyclopentadienyl benzyl halide compound having the same structure as the compound of formula (V-bis), except that the-OH group is replaced by the corresponding-Cl or-Br, preferably Br, halide; e) reacting the cyclopentadienyl benzyl halide obtained in step (d) with a compound of formula HA' (Li or MgR)⁸) Wherein A' has the same definition as in formula (V), R⁸Selected from Cl, Br or A' such as indenyl, fluorenyl or cyclopentadienyl lithium or various substitutes thereof, in a suitable solvent, preferably a THF/hexane mixture, at a temperature of 10 to 40 ℃ to obtain the desired ligand.

Thus, another aspect of the present invention relates to a catalyst for the (co) polymerization of ethylene and other alpha-olefins, such as the homopolymerization of ethylene and other alpha-olefins, the copolymerization of ethylene with one or more other comonomers, such as alpha-olefins, conjugated or non-conjugated dienes, styrene derivatives, etc., the copolymerization of alpha-olefins with each other or with other copolymerizable monomers. The catalyst comprises at least the following two components, or is obtained by contacting and reacting the following two components:

at least one metallocene complex having the formula (II),

(ii) a cocatalyst consisting of at least one organic compound of an element M' different from carbon, chosen from the elements of groups 2, 12, 13 or 14 of the periodic Table of the elements, as defined above.

In particular, the element M' of the invention is selected from boron, aluminum, zinc, magnesium, gallium and tin, more preferably boron and aluminum.

In a preferred embodiment of the invention, the constituent (ii) is an organic oxidic derivative of aluminium, gallium or tin, this can be defined as an organic compound of M' in which the latter is bonded to at least one oxygen atom and at least one organic group consisting of an alkyl group having from 1 to 6 carbon atoms, preferably a methyl group.

Component (ii) of the present invention is more preferably an aluminoxane. As is known, aluminoxanes are compounds containing Al-O-Al bonds with varying O/Al ratios, obtainable in the prior art by reacting an aluminum alkyl or an aluminum alkyl halide with water or other compounds containing a predetermined amount of available water under controlled conditions, for example, trimethylaluminum with aluminum sulfate hexahydrate, copper sulfate pentahydrate or iron sulfate pentahydrate. Preferred aluminoxanes for use in forming the polymerization catalyst of the present invention are oligomeric or polymeric, cyclic or linear compounds characterized by a repeating unit of the formula:wherein R is₅Is C₁-C₆Alkyl, preferably methyl.

Each aluminoxane molecule preferably contains from 4 to 70 repeating units, which need not be identical to one another, but may contain different R₅A group.

These aluminoxanes, in particular methylaluminoxane, are compounds which can be obtained by known organometallic chemical methods, for example by adding trimethylaluminum to a hexane suspension of aluminum sulfate hydrate.

When used to form the polymerization catalyst of the present invention, the aluminoxane is contacted with a proportion of a complex of the formula (II) in which the atomic ratio between Al and the metal M is from 10 to 10000, preferably 100-5000. The order in which the complex (i) and the aluminoxane (ii) are contacted with each other is not critical.

In addition to the above-mentioned aluminoxanes, also gallium-containing siloxanes (in the above-mentioned formulations, gallium is used instead of aluminum) and stannoxanes are included in the component (ii) according to the present invention, which act as cocatalysts for the copolymerization of olefins in the presence of metallocene complexes, as disclosed for example in US5,128,295 and US5,258,475.

According to another preferred embodiment of the invention, the catalyst is obtainable by: contacting a component (i) consisting of at least one complex of formula (II) with a component (II) consisting of at least one compound or a mixture of organometallic compounds of M 'capable of reacting with the complex of formula (II) to extract the sigma-bonded R' or R 'groups therefrom, to form, on the one hand, at least one neutral compound and, on the other hand, an ionic compound consisting of a metallocene cation containing the metal M and a noncoordinating organic anion containing the gold complex M'. Their negative charges are delocalized in multicenter structures.

Suitable as component (ii) for the above type of ionizing system are preferably bulky organic compounds of boron and aluminum such as those represented by the following general formula: [ (R)_C)_XNH_4-X]^＋×[B(R_D)₄]^－；B(R_D)₃；[Ph₃C]^＋×[B(R_D)₄]^－；[(R_C)₃PH]^＋×[B(R_D)₄]^－；[Li]^＋×[B(R_D)₄]^－；[Li]^＋×[Al(R_D)₄]^－(ii) a Wherein the subscript "X" is an integer of from 0 to 3, and each R_CThe radicals independently represent an alkyl or aryl radical having 1 to 10 carbon atoms, each R_DThe radicals independently represent partially or preferably fully fluorinated aromatic groups having 6 to 20 carbon atoms.

These compounds are generally used in such an amount that the ratio of the atoms M' of component (ii) to the atoms M of the metallocene complex is from 0.1 to 15, preferably from 0.5 to 10, more preferably from 1 to 6.

Component (ii) may be prepared from a single compound, usually an ionic compound, or such a compound with MAO or preferably with an aluminium trialkyl having from 1 to 8 carbon atoms in each alkyl residue, e.g. AlMe₃，AlEt₃,Al(i-Bu)₃And (3) the composition of the mixture.

Generally, the preparation of the ionic metallocene catalysts of the present invention is preferably carried out in an inert liquid medium, more preferably in a hydrocarbon. The choice of components (i) and (ii), preferably mixed with each other and using a particular method, can vary on the basis of the molecular structure and the desired result, according to methods well described in the detailed literature and known to the person skilled in the art.

The following examples of these methods are briefly and qualitatively described, but are not meant to limit the present invention: (m)₁) The metallocene of the above formula (II) in which at least one, preferably both, of the substituents R 'and R' are hydrogen or alkyl, is brought into contact with an ionic compound whose cation is capable of reacting with one of the substituents to form a neutral compound whose anion is bulky, noncoordinating and capable of dissociating from a negative charge. (m)₂) The metallocene of the above formula (II) is reacted with an alkylating agent, preferably trialkylaluminum, in excess, in a molar amount of from 10/l to 300/l, and then with a strong Lewis acid, such as tris (pentafluorophenyl) boron, in practice in stoichiometric or slight excess with respect to the metal M. (m)₃) The metallocene of the above formula (II) is contacted and reacted with a molar excess of a trialkylaluminum or alkylaluminum halide, which may be of the formula AlR, in the range from 10/l to 1000/l, preferably from 100/l to 500/l_mX_3-mWherein R is linear or branched C₁-C₈Alkyl, or mixtures thereof, X is halogen, preferably chlorine or bromine, "m" is a decimal number between 1 and 3; at least one ionic compound of the above-mentioned type is then added to the composition thus obtained in such an amount that, in the metallocene complex, the ratio of B or Al to the atoms M is between 0.1 and 15, preferably between 1 and 6.

Examples of ionizing ionic compounds or multicomponent reaction systems which can be prepared by reaction with the metallocene complexes of the present invention to give ionic catalyst systems are described in the following patents, which are incorporated herein by reference: published european patent application:

EP-A277,003，EP-A277,004，EP-A522,581，EP-A495,375，EP-A520,732，

EP-A478,913, EP-A468,651, EP-A427,697, EP-A421,659, EP-A418,044; -published international patent application: WO92/00333, WO92/05208, WO 91/09882. US5064802, US2827446, US 5066739.

Non-limiting examples of complex-cocatalyst mixtures suitable for preparing the ionic catalytic system of the present invention are briefly described in the following table (1), which are obtainable from the respective precursors of their mixtures. If desired, any compound in each column can be combined with any compound in the other columns according to the specified method. TABLE 1 methods metallocene (i) cocatalyst (ii)

o-BZD- [1- (3, 5-dimethyl) Ind]₂ZrMe₂

o-BZD-[1-(4，5，6，7-THInd)₂TiMe₂

o-BZD-[1-(4，5，6，7-THInd)₂ZrMe₂ [Ph₃C]^＋×[B(C₆F₅)₄]^－

o-BZD- [1- (3-methyl) Ind]₂HfH₂(m₁)o-BZD-(1-Ind)₂ZrMe₂ [Bu₃NH]^＋×[B(C₆F₅)₄]^－

o-BZD-(1-Ind)₂TiPr¹ ₂o-BZD- [1- (3, 4, 7-trimethyl) Ind]₂ZrH₂ [PhNMe₂H]＋×[B(C₆F₅)₄]^－ ₄o-BZD- [1- (4, 7-dimethyl) Ind]₂TiBz₂o-BZD-(Cp^*)₂ZrMe₂o-BZD- [1- (5, 6-dimethyl) Ind]₂ZrCl₂o-BZD- [1- (4, 7-dimethyl) Ind]₂TiBr₂l，8-Naphth-(1-Ind)₂ZrCl₂ [Ph₃C]^＋×[B(C₆F₅)₄]^－l，8-Naphth-(1-Ind)₂Zr(NMe₂)₂o-BZD-(Flu)₂ZrCl₂ AlEt₃o-BZD- [1- (3-methyl) Ind]₂HfCl₂(m₃) o-BZD- [1- (3-methyl) Ind]₂TiCl₂ [PhNMe₂H]^＋×[B(C₆F₅)₄]^－ ₄o-BZD-(1-Ind)₂ZrCl₂o-BZD-(Flu)₂HFCl₂ AlBu₃ ¹o-BZD-(1-Ind)₂Ti(OCOCHEtBu)Cl(Flu-o-BZD-Cp^*)Ti(NMe₂)₂ [Bu₃NH]^＋×[B(C₆F₅)₄]^－o-BZD-[1-(4，5，6，7-THInd)₂TiCl₂o-BZD- [1- (4, 7-dimethyl) Ind]₂TiCl₂o-BZD-(1-Ind)₂Zr[OCO(CH₂)₅C(Me)₃]₂For short: me ═ methyl, Et ═ ethyl, Bu ═ n-butyl, Bu¹Isobutyl, Ph ═ phenyl, Bz ═ benzyl, Pr¹Iso-propyl, ind ═ indenyl, THind ═ 4,5, 6, 7-tetrahydroindenyl, Flu ═ fluorenyl, o-BZD ═ o-benzylidene

Also included within the scope of the present invention are those catalysts comprising two or more complexes of formula (I) in admixture with each other. Catalysts of the invention based on mixtures of complexes having different catalytic activities can be used advantageously in the polymerization when it is desired to prepare polyolefins having a broad molecular weight distribution.

According to another aspect of the invention, for the preparation of the solid component forming the olefin polymerization catalyst, the above-mentioned complexes can also be loaded onto an inert solid preferably consisting of Si and/or Al oxides, such as silica, alumina or aluminosilicates. Known loading techniques can be used for loading these catalysts. Which generally comprises, in a suitable inert liquid medium, contacting a support which can be activated by heating to a temperature in excess of 200 ℃ with one or two of the catalyst components (i) and (II) of the invention, it being not necessary for the purposes of the invention to carry both components, it being possible for each complex of the formula (II) to be present alone or the abovementioned organic compounds B, Al, Ga or Sn to be present on the surface of the support. In the latter case, the component not present at the surface is subsequently contacted with the loaded component, while forming an activated polymerization catalyst.

The scope of the present invention also includes complexes and catalyst systems derived therefrom, which are loaded onto the solid by functionalization of the latter and formation of a covalent bond between the solid and the metallocene complex contained in the formula (II) above.

A particular process for forming a supported catalyst according to the invention comprises prepolymerising a minor portion of a monomer or mixture of monomers in the presence of the catalyst so as to be contained in solid particles, which are then fed to a reactor, the process being completed in the presence of additional alpha-olefin. This allows a better control of the morphology and the size of the polymeric particles obtained.

In addition to two components (i) or (ii), one or more other additives or components may optionally be added to the catalyst of the invention in order to obtain a catalytic system suitable for meeting the specific requirements. The catalytic systems thus obtained are included within the scope of the present invention. The additives or components used for the preparation and/or compounding of the catalysts of the present invention are inert solvents, such as aliphatic and/or aromatic hydrocarbons, aliphatic and aromatic ethers, such as weakly coordinating additives (Lewis bases) selected from the group consisting of non-polymeric olefins, ethers, tertiary amines and alcohols, halogenating agents such as silicon halides, halogenated hydrocarbons, preferably chlorinated hydrocarbons, etc., and furthermore, all other possible components which are generally used in the prior art for the (co) polymerization of ethylene and alpha-olefins for the preparation of conventional homogeneous metallocene-type catalysts.

The components (i) and (ii) are brought into contact with each other to form the catalyst of the invention, preferably at a temperature of from room temperature to 60 ℃ for a period of from 10 seconds to 1 hour, preferably from 30 seconds to 10 minutes.

The catalysts of the invention can be used in virtually all known processes for the (co) polymerization of olefins, which can be continuous or batchwise, in one or more stages, for example, involving low (0.1-1.0MPa), medium (1.0-10MPa) or high (10-150MPa) pressures at temperatures of 20 to 240 ℃ and preferably in the presence of an inert diluent, with excellent results. Hydrogen is conveniently used as a molecular weight regulator.

These processes can be carried out in solution or suspension in a liquid diluent, which generally consists of an aliphatic or cycloaliphatic saturated hydrocarbon having from 3 to 8 carbon atoms. It may also consist of monomers as in the known copolymerization processes of ethylene and liquid propylene, the amount of catalyst introduced into the polymerization mixture being preferably determined in such a way that: which can make the concentration of metal M10^-510^-8Mol/l.

The polymerization can alternatively be carried out in the gas phase, e.g.in a fluidized-bed reactor, which is usually operated at a pressure of from 0.5 to 5MPa and a temperature of from 50 to 150 ℃.

According to a particular aspect of the invention, the catalyst for the (co) polymerization of ethylene and of an alpha-olefin is prepared separately (preformed) by contacting components (i) and (ii) and then introduced into the polymerization environment. The catalyst may be introduced first into the polymerization reactor and then the reagent mixture containing the olefin or olefin mixture to be polymerized, or the catalyst may be introduced into the reactor already containing the reagent mixture, or finally, the reagent and catalyst may be fed simultaneously into the reactor.

According to another aspect of the invention, the catalyst is formed in situ, e.g., by separately introducing components (i) and (ii) into a polymerization reactor containing the preselected olefin monomer.

Excellent results are obtained with the catalyst of the invention, which can be used for the polymerization of ethylene to obtain linear polyethylenes, for the copolymerization of ethylene with propylene or higher alpha-olefins having from 4 to 10 carbon atoms, obtaining copolymers with different characteristics depending on the specific polymerization conditions and on the quantity and structure of the alpha-olefins themselves. For example, a linear polyethylene having a density of 0.880 to 0.940 and a molecular weight of 10,000-2,000,000 can be obtained. In the preparation of low or medium density linear polyethylenes (known in terms of density for short as ULDPE, VLDPE and LLDPE), the alpha-olefins used as comonomers for ethylene are preferably 1-butene, 1-hexene and 1-octene.

The catalyst of the invention can also be conveniently used in a process for the copolymerization of ethylene and propylene, obtaining vulcanizable saturated elastomeric copolymers by means of peroxides, which are very resistant to ageing and degradation, or in the terpolymerization of ethylene, propylene and a non-conjugated diene having from 5 to 20 carbon atoms, to obtain vulcanizable rubbers of the EPDM type, in the case of these latter processes, it has been observed that the catalyst of the invention, under the polymerization conditions, makes it possible to prepare polymers having a particularly high diene content and high average molecular weight.

For the preparation of EPDM, the dienes which can be used to prepare these terpolymers are preferably selected from: dienes having a linear chain, such as 1, 4-hexadiene and 1, 6-octadiene; branched dienes, such as 5-methyl-1, 4-hexadiene; 3, 7-dimethyl-1, 6-octadiene; 3, 7-dimethyl-1, 7-octadiene; dienes having a single ring, such as 1, 4-cyclohexadiene; 1, 5-cyclo-octadiene; 1, 5-cyclododecadiene; dienes having bridged fused rings, such as dicyclopentadiene; bicyclo [2.2.1] hepta-2, 5-diene; alkenyl, alkylene, cycloalkenyl and cycloalkylene norbornenes, such as 5-methylene-2-norbornene, 5-ethylidene-2-norbornene (ENB), 5-propenyl-2-norbornene.

Among the non-conjugated dienes typically used to prepare these copolymers, dienes containing at least one double bond in the strained ring are preferred, and more preferred are 5-ethylidene-2-norbornene (ENB), 1, 4-hexadiene and 1, 6-octadiene.

In the case of EPDM terpolymers, the amount of diene monomer does not exceed 15% by weight, preferably from 2 to 10% by weight. On the other hand, the propylene content is usually from 20 to 50% by weight.

The catalysts of the present invention can also be used in the processes for the homo-and copolymerization of alpha-olefins known in the art to obtain atactic, isotactic or syndiotactic polymers in very high yields, depending on the structure and geometry of the metallocene complexes of formula (II). Suitable alpha-olefins for this purpose are those having from 3 to 20 carbon atoms, optionally including a halogen or aromatic nucleus, such as propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-decene and styrene.

FIGS. 1 and 2 are X-ray structural diagrams and, respectively, of a complex of formula (VIII)¹H-NMR spectrum chart.

FIG. 3 is a drawing of a complex of formula (XV)¹H-NMR spectrum chart.

FIG. 4 shows a scheme for preparing a complex of formula (XXII)¹H-NMR spectrum chart.

The invention is further described by the following examples, which are intended to be illustrative only and not limiting to the scope of the invention itself. Examples

The analytical techniques and methods listed and briefly described below were used in the examples below.

By means of the following examples¹Characterization of H-NMR spectroscopy was performed on a nuclear magnetic resonance spectrometer model Bruker-MSL-300 using CDCl₃As a solvent for each sample.

The measurement of the molecular weight of the olefin polymer was carried out using Gel Permeation Chromatography (GPC). The analysis of the samples was carried out on 1, 2, 4-trichlorobenzene (stabilised with Santonox) at a temperature of 135 ℃ using a WATERS150-CV chromatograph and a Waters differential refractometer as detector.

The chromatographic separation was performed using a set of mu-Styragel HT columns (Waters) with three wells each having a size of 10³，10⁴，10⁵, two holes of size 10⁶ are provided. The flow rate of the eluent was set at 1 ml/min.

Data were obtained and processed using Maxima 820 software version 3.30 (Millipore); the calculation of the number average molecular weight (Mn) and the weight average molecular weight (Mw) was carried out by a general calibration method for which polystyrene standards having a molecular weight of 6,500,000 and 2,000 were selected.

The structure of the novel complexes of the invention was determined on a Siemens AED diffractometer with the aid of X-rays.

The mechanical properties of the product were determined by vulcanizing the copolymer. Corresponding methods, as well as techniques well-defined in the technical literature, which are effective for all these analyses are provided below.

The content of units derived from propylene and possibly diene in the polymer is determined (according to the method of the applicant) by means of IR analysis of the polymer in the form of a film having a thickness of 0.2mm using an FTIR Perkin-Flmer spectrophotometer model 1760. Relative to 4255cm^-1The peak at (A) was determined to be 4390cm for propylene^-1And ENB at 1688cm^-1The intensity of the characteristic peak at (a), the amount of which is determined by using a standard calibration curve.

The flow index (melt flow index, MFI) of the polymer is determined by the rule ASTM D-1238D. Mooney viscosity (1 + 4) was measured at 100 ℃ using a Monsanto "1500S" viscometer according to method STM 1646/68.

As far as the mechanical properties are concerned, their analysis is carried out on vulcanized polymers. (A) Vulcanization formulations, (B) dynamic mechanical properties measurements according to the methods indicated herein are as follows. A) Vulcanization

The vulcanization mixture was prepared using the formulation of table 2 below. TABLE 2

EPDM polymer 100 'low structure of high abrasion furnace' type carbon black FEF in weight portion of formula^(CABOT) 55 Zinc oxide 5 Sulfur 1.5 Tetramethylthiuram disulfide1.5 mercaptobenzothiazole 0.75 Paraffin oil EIL 570^Density 0.88g/cc (EXXON) 30

The mixture homogenized in the roll mixer was vulcanized between platens at a pressure of 18MPa and a temperature of 165 ℃ for a period of 40 minutes. B) Mechanical characteristics

The mechanical properties of the vulcanized copolymers were determined on dumbbell test specimens obtained from vulcanized plaques.

Ultimate tensile strength is measured according to ASTM D412-68, elongation at break is measured according to ASTM D412-68, and Shore A hardness is measured according to ASTM D2240-68.

During the preparation of the samples, the following listed commercial reagents were used: methyllithium (MeLi) in diethyl ether 1.6M butyllithium (BuLi) in ALDRICH Hexane 2.5M ALDRICH zirconium tetrachloride (ZrCl)₄) FLUKA indene FLUKA Methylaluminoxane (MAO) (Eurecene 510010T) WITCO 10% w/v Al ortho bromobenzyl alcohol ALDRICH 2-methoxypropene ALDRICH 1-indanone ALDRICH in toluene

The reagents and/or solvents employed and not indicated above are those commonly used and readily available from manufacturers in the field. Example 1: ortho-benzylidene bis- (. eta.)⁵Synthesis of (E) -1-indenyl) -zirconium dichloride 1) Synthesis of 1- (1-indenyl) -2-methylene- (1-indenyl) -benzene (formula VI)

0.4ml of phosphorus oxychloride (POCl)₃) Was added as a catalyst to a mixture of 14g of o-bromobenzyl alcohol (75mmol) and 72ml of 2-methoxypropene (75 mmol). The alcohol slowly dissolved and the mixture was kept stirring at room temperature for 2 hours. Neutralizing with triethylamine, and drying to obtain20g of an oily residue consisting essentially of 2-methoxy-2- (o-bromobenzyloxy) propane.

The residue was diluted with 150ml of hexane, then 30ml of 2.5MBuLi in hexane was added. A precipitate formed. The mixture was left to stand for 2 hours, then filtered and washed with hexane to obtain the salt 2- [ (1-methyl-1-methoxy) ethoxy-methyl ] phenyl lithium.

10g of 1-indanone (75mmol) dissolved in 50ml of THF are added to a lithium salt dissolved in 100ml of THF and then cooled to-70 ℃. The mixture was allowed to warm to room temperature overnight. It is then poured into water and 50ml of a 1: 1 aqueous HCl solution are added. The mixture was kept under stirring for 2 hours. Extraction is then carried out with ether and the extract is washed with bicarbonate until neutral. The solvent was evaporated and eluted on a silica gel column using 10% ethyl acetate in petroleum ether to give 7.6g of a helical benzofuran derivative having the following structural formula (VI):(VI)

after the following reaction scheme (I), 6.5g of the spirofuran derivative (V) (29mmol) were suspended in 50ml of 48 wt% aqueous HBr, and the thus-obtained mixture was kept stirred at room temperature for 50 hours. Then diluted with 10ml of water, extracted with ether, the organic phase separated, neutralized and then dried by evaporation of the ether. The semi-solid residue was purified by chromatography on a silica gel column eluting with a 9: 1 mixture of petroleum ether and dichloromethane. Finally, after evaporation of the eluent, 6.1g of o- (1-indenyl) -benzyl bromide (21mmol) were isolated.Reaction scheme (I)

8ml of a 2.5 molar solution of butyllithium in hexane (20mmol) were added at room temperature to a solution of 4g of indene (34mmol) in a mixture of 100ml of THF and 30ml of hexane. The mixture was kept stirring for 4 hours and then cooled to-80 ℃. 5.7g of o- (1-indenyl) -benzyl bromide (20mmol) obtained above are added to the mixture, and the temperature is then raised to room temperature in about 2 hours, the mixture thus obtained is hydrolyzed and then extracted with diethyl ether, after neutralization, drying and evaporation of the ether the residue remaining in the organic phase is purified by means of a silica gel column chromatography, eluted with petroleum ether and finally, after evaporation of the eluent, 5.7g of a white solid are obtained, which, after spectroscopic examination, proves to be the desired product of the formula (VII) (17 mmol). 2) Synthesis of zirconium Complex (formula VIII)

Under an argon atmosphere, 1.74g of the compound of formula (VII) (obtained as above (5.44mmol), dissolved in 50ml of anhydrous ether) are introduced into a 100ml tailed test tube equipped with a magnetic stirrer. 8ml of a 1.6 molar solution of butyllithium in hexane (12.8mmol) are added dropwise at room temperature to the pale yellow solution, the mixture is left stirring for about 10 hours, and finally the reaction mixture assumes a dark red solution, the volume of which is reduced to 10ml, and then 30ml of anhydrous n-hexane are added, a suspension forming immediately. Then filtering the mixture; the solid was collected and then washed 3 times with 10ml of n-hexane, and the dilithium derivative of compound (VII) thus obtained was dried under vacuum (about 10Pa) and then transferred under an argon atmosphere to a 100ml tailed test tube containing 50ml of toluene, obtaining a suspension which was cooled to 0 ℃. Weigh 1.5gZrCl alone₄(6.44mmol) and then introduced into the toluene suspension under argon. After stirring at 0 ℃ for about 1 hour, the temperature was raised to room temperature and stirring was continued for a further 30 minutes, after which the mixture was filtered on a porous septum and the mother liquor containing the desired complex was collected, the residue was washed with toluene (3X 10ml) and the wash water was added to the mother liquor. The clear toluene solution thus obtained was left to stand at room temperature for about 2 days, orange crystals formed, these were isolated by filtration, washed with a little toluene and characterized by NMR and X-ray. 0.82g of the desired complex (formula VIII) is obtained in 31% yield, based on the amount of starting ligand.(VIII)

X-ray structures of complexes having formula (VIII) and¹H-NMR Spectroscopy (C)₂D₂Cl₄δ ppm rel.to TMS) are shown in fig. 1 and 2, respectively. Examples2: ortho-benzylidene bis- (5, 6-dimethyl-. eta.) -⁵Synthesis of (E) -1-indenyl) -zirconium dichloride 1) Synthesis of 5, 6-dimethyl-2, 3-dihydro-1-indanone (Xa) and 5, 6-dimethylindene (XIa)

A mixture of 69g (0.543mol) of 3-chloropropionylchloride and 58g (0.547mol) of o-xylene is added to 164g (1.23mol) of AlCl in the course of 1 hour under argon₃In a solution of 500ml of nitromethane, cooling was carried out with a water bath (25 ℃). After the addition was complete, the mixture was stirred for 5 hours, then the reaction mass was poured into 500g of ice containing 100ml of concentrated HCl. Extraction was performed with diethyl ether. The ether extract was washed with 2N hydrochloric acid and then with saturated aqueous NaCl until neutral. Then, dehydration drying over sodium sulfate and evaporation of the solvent gave 106.3g of compound (IX) (98% yield).

106.3g of compound (IX) are slowly added to 420ml of concentrated sulfuric acid. After the addition was complete, the temperature was raised to 90 ℃ and the temperature was maintained for 3 hours, and then the mixture was poured into ice. Extraction with toluene, washing of the organic extract with saturated sodium bicarbonate solution and finally with saturated aqueous NaCl solution to neutrality, after which the solution is treated with activated carbon, filtered and dried over sodium sulfate and the residue obtained after evaporation is recrystallized from petroleum ether to yield 25g (156mmol) of a mixture of 5, 6-dimethyl-and 6, 7-dimethyl-2, 3-dihydro-1-indanone Xa and Xb in a mixing ratio of 1: 1 (29% yield).Xa Xb

3.8g (101mmol) of sodium borohydride are added portionwise to a solution of 25g (156mmol) of the mixture of 2, 3-dihydro-1-indanone Xa and Xb obtained above in THF, which mixture is kept at 10 ℃ under an inert atmosphere. After the addition was completed, the temperature was raised to room temperature, the mixture was stirred for 1 hour, the reaction mixture was poured into water and ice, and extraction was performed with diethyl ether to obtain a mixtureContaining both the reduction products XIa and XIb indicated by the following schemes. The ether extract was washed with water to neutrality and then dried over sodium sulfate. The residue from the evaporation of the solvent was recrystallized from petroleum ether to yield 6.5g of the single isomer 5, 6-dimethyl-1, 2-dihydro-1-indanol (XIa) (26% yield).

6.5g (0.401mol) of 5, 6-dimethyl-1, 2-dihydro-1-indanol (XIa), 10g of silica (MERCK), 70ml of toluene and 70ml of heptane are added and mixed in a Markusson apparatus, heating is carried out under reflux, the water produced is removed by azeotropic distillation, the reaction is carried out for a total of 16 hours, the mixture is filtered, diluted with diethyl ether, washed with water and the organic phase is dried over sodium sulfate. After evaporation of the solvent, 5.2g5, 6-dimethyl-indene (90% yield) were obtained. 2) Synthesis of 1- (5, 6-dimethyl-1-indenyl) -2- (5, 6-dimethyl-1-indenyl) methylbenzene (XIV)Reaction scheme (II)

27ml (0.067mol) of a solution of 2.5M n-BuLi in hexane were added to a solution of 18.2g (0.07mol) of 2-methoxy-2- (o-bromobenzyloxy) propane (obtained as described in paragraph 1 of example 1 above) in 120ml of hexane. The mixture was stirred for 2 hours, then the hexane solution was decanted, and the solid residue was washed with hexane and decanted, then dissolved in THF.

The mixture was cooled to-80 ℃ and a solution of 11.0g (0.068mol) of 4, 7-dimethyl-2, 3-dihydro-1-indanone (formula Xa) dissolved in 30ml of THF was added. The temperature was raised to room temperature overnight, and the mixture was poured into water and ice, to which 50ml 1: l HCl was added. The mixture was stirred at 0 ℃ for 2 hours. Extraction with diethyl ether followed by washing with a saturated solution of sodium bicarbonate and then with water to neutrality. After the organic phase was dried over sodium sulfate, the solvent was evaporated. The residue was purified by chromatography on a silica gel column eluting with a 9: 1 mixture of hexane: ethyl acetate, and after evaporation of the eluent, 7.0g (0.028mol) of the spirofuran derivative of formula (XII) were collected (see scheme II, 42% yield).

The above spirofuran derivative was placed in 48ml of 48% HBr and the reaction was kept at reflux temperature for 16 hours. Finally, dilution with water, extraction with diethyl ether, washing of the ether phase with a saturated solution of sodium bicarbonate and then with water to neutrality, dehydration drying of the organic phase over sodium sulfate and evaporation of the solvent, the residue obtained is purified by chromatography on a silica gel column eluting with a 9: 1 mixture of hexane: ethyl acetate, thus obtaining 5.3g (0.0168mol) of o- [1- (5, 6-dimethyl) -indenyl ] benzyl bromide (formula XIII, scheme III, 60% yield).

14.4ml (36.1mmol) of a solution of 2.5M n-BuLi in hexane are added to 5.2g (0.0388mol) of 5, 6-dimethylindene (obtained as above, formula Xia, dissolved in a solution of 100ml of a mixture of THF and 50ml of hexane). After the addition was complete for 2 hours, the mixture was cooled to-70 ℃ and 5.3g (0.0168mol) of o [1- (5, 6-dimethyl-indenyl) dissolved in 50ml of THF were added]Benzyl bromide (formula XIII). After the addition was complete, the temperature of the mixture was raised to room temperature and stirred for 3 hours, it was poured into water which was slightly acidified with hydrochloric acid and then extracted with diethyl ether, the organic phase was neutralized by washing with water and dried over sodium sulfate. The solvent was then distilled off. The residue was purified on a silica gel column by using petroleum ether as eluent to obtain 60g of a solid which, after characterization by spectroscopy, proved to be the desired ligand: 1- (5, 6-dimethyl-1-indenyl) -2- (5, 6-dimethyl-1-indenyl) methylbenzene (XIV).(XIV) reaction scheme (III)3) Synthesis of zirconium Complex

The same molar amounts of bis-indenyl ligand and zirconium tetrachloride were reacted under the same conditions by the same procedure as in the 2 nd stage of example 1. 1.95g of the compound of the formula (XIV) (5.2mmol) are reacted with 7.5ml of butyllithium solution and then with 1.45g of ZrCl₄Reaction, finally 0.8g of the desired complex of the formula (XV) are obtained.(XV)

FIG. 3 shows a complex of formula (XV)¹H-NMR Spectroscopy (C)₂D₂Cl₄δ ppm rel.to TMS). Example 3: ortho-benzylidene bis- (4, 7-dimethyl-. eta.) -⁵Synthesis of (E) -1-indenyl) -zirconium dichloride 1) Synthesis of 4, 7-dimethyl-2, 3-dihydro-1-indanone (XVII) and 4, 7-dimethyl-indene (XVIII)

The procedure of scheme (IV) was repeated, 10ml of 3-chloropropionyl chloride solution in 14.5g (0.136mol) of p-xylene at 0 ℃ under an inert atmosphere was added dropwise to 16g (0.120mol) of AlCl in about 1 hour₃In a suspension of 70ml dichloromethane. After the addition was completed, the temperature was raised to 10 ℃ and maintained at 10-20 ℃ for about 2 hours, the reaction mixture was poured into ice, extracted with dichloromethane, the organic extract was washed with water to neutrality, the organic phase, after separation, was dried with water over sodium sulfate, and after evaporation of the solvent, a residue was obtained which mainly contained the compound of formula (XVI) indicated in scheme (IV) below.

The residue was added to 90ml of concentrated sulfuric acid at a rate to maintain the temperature in the range of 20-30 ℃. After the addition was complete, the temperature was raised to 80 ℃, the mixture was stirred for 2 hours, then it was poured into ice, extracted with ether, the solution was saturated with sodium bicarbonate, the ether solution was washed with water again to neutrality and finally dried over sodium sulfate. The solid obtained by evaporating the ether was washed with petroleum ether and then dried, thus obtaining 20g of 4, 7-dimethyl-2, 3-dihydro-1-indanone (formula XVII of scheme IV below, yield in two steps 91%).Reaction scheme (IV)

2.9g (0.0181mol) of 4, 7-dimethyl-1-2, 3-dihydro-1-indanone (formula XVII) obtained as described above are slowly added to 0.350g (0.0692mol) of LiAlH under an inert atmosphere, maintained at-30 ℃₄In a suspension of 30ml of diethyl ether. The reaction was complete after 30 minutes. Ice and 2N hydrochloric acid were carefully added untilAcidification, then the mixture is washed with ether, after which the organic phase is separated and washed to neutrality, dried over sodium sulfate and evaporated to give a residue consisting essentially of 4, 7-dimethyl-1-1, 2-indanol. The residue was dissolved in 10ml of THF, a small amount of p-toluenesulfonic acid was added, the mixture was brought to reflux temperature over 1 hour, and then solid sodium bicarbonate and sodium sulfate were added. The mixture was filtered and the solvent was evaporated to give 2.4g of 4, 7-dimethyl-indene (XVIII) (91% yield). 2) Synthesis of 1- (4, 7-dimethyl-1-indenyl) -2- (4, 7-dimethyl-1-indenyl) methylbenzene (XXI)Reaction scheme (V)

30ml (75mmol) of a solution of 2.5M n-BuLi in hexane are added to a solution of 20g (77.22mmol) of 2-methoxy-2- (o-bromobenzyloxy) propane (obtained as described in example 1.1 above) in 150ml of hexane. After the addition, the mixture was stirred for 2 hours and the corresponding lithium salt was precipitated as in example 1 above. The hexane was decanted off, and the solid was washed with hexane again and then dissolved in 100ml of THF. The mixture was cooled to-70 ℃ and then 12.12g (75.75mmol) of the 4, 7-dimethyl-2, 3-dihydro-1-indanone obtained above dissolved in sufficient THF was slowly added. The temperature was raised to room temperature overnight, it was poured into ice acidified with 50ml1/1 aqueous hydrochloric acid, stirred for 2 hours, then extracted with ether, the organic phase was neutralized by washing with sodium bicarbonate and water, dried over sodium sulfate, after evaporation of the solvent, the residue was purified on a silica gel chromatography column by elution with 9: 1 hexane/ethyl acetate to obtain 10g of the alcohol of formula (XIX) (scheme V, 53% yield).Reaction scheme (VI)

Maintaining at 0 deg.C, a small amount of PBr₃Adding to a solution of 6.0g (24mmol) of an alcohol of formula (XIX) in 50ml of dichloromethane, controlling the reaction tendency by Thin Layer Chromatography (TLC) until the alcohol disappears, after which a saturated solution of sodium bicarbonate is added dropwise at 0 deg.C, and the mixture is taken up with 1Extraction with 00ml of dichloromethane, washing of the extract to neutrality, drying by dehydration and evaporation of the solvent the residue obtained is eluted with a mixture of hexane: ethyl acetate 9: 1 and purified by chromatography on a column on silica gel, obtaining, after evaporation of the eluent, 4.0g of the brominated compound of formula (XX) in scheme (VI) (52% yield).

4.12ml (10.3mmol) of 2.5M n-BuLi in hexane were added to a solution of 1.48g of 4, 7-dimethylindene (XVIII) (10.3 mmol; obtained as above) in 55ml of a THF-hexane 2/1 mixture. After the addition was complete, the mixture was stirred for 1 hour, then it was cooled to-70 ℃ and then a solution of 2.3g (7.37mmol) of the bromo compound of formula (XX) in THF/hexane was added dropwise, the temperature of the mixture was raised to room temperature, it was left to stand for 6 hours, then it was poured into water, extraction was carried out with diethyl ether, the organic phase was washed to neutrality, dehydration was carried out over sodium sulfate, the residue obtained by evaporation of the solvent was purified by means of a silica gel column chromatography using petroleum ether, after evaporation of the eluent, 2.0g of the bisindenyl ligand of formula (XXI) indicated below were obtained (72% yield).(XXI)3) Synthesis of zirconium complexes (formula XXXII)

The same molar amounts of bis-indenyl ligand and zirconium tetrachloride were reacted under the same process conditions using the same procedure as in paragraph 2 of example 1. 1.95g of the compound of the formula (XXI) (5.2mmol) are reacted with 7.5ml of butyllithium solution and then with 1.45g of ZrCl₄Reaction, 0.9g of the desired complex of the formula (XXII) is finally obtained.(XXII)

FIG. 4 shows a complex of formula (XXII)¹H-NMR Spectroscopy (C)₂D₂Cl₄Totms, δ ppm rel). Examples 4 to 9: ternary polymerization of ethylene/propylene/ethylidene norbornene

Examples 4 to 9 relate to the terpolymerization tests for the preparation of elastomeric copolymers of EPDM type based on ethylene/propylene/ethylidene norbornene, using a preformedCatalyst system comprising, in one aspect, the metallocene complex o-benzylidene bis- (. eta.) obtained in example 1 above⁵-1-indenyl) zirconium dichloride, on the other hand Methylaluminoxane (MAO) as cocatalyst. The specific polymerization conditions and results obtained for each example are shown in Table 3 below, which sequentially provides the cited example numbers, the amount of zirconium used, the atomic ratio of aluminum to zirconium in MAO, the polymerization pressure, the initial molar concentration of Ethylidene Norbornene (ENB) in liquid propylene, the activity of the zirconium-based catalyst system, C in the polymer₂，C₃Relative amounts (by weight) of the units and ENB, weight average molecular weight Mw and molecular weight distribution index Mw/Mn.

The polymerization was carried out in a 0.5 l pressure reactor equipped with a thermostat and a magnetic stirrer. The reactor was previously washed with a dilute MAO solution in toluene (about 0.1M calculated as Al) in the usual manner and then dried under vacuum (0.1Pa, several hours).

At room temperature, 120g of "polymerization grade" liquid propylene was fed into the reactor together with the amount of ENB necessary to achieve the desired concentration. The polymerization temperature of the reactor was then raised to 40 ℃ and gaseous ethylene was then introduced through the immersion tube until the desired equilibrium pressure of the liquid mixture (22-28ate) was reached with slight agitation. Under these conditions, the molar concentration of ethylene in the liquid phase is between 12 and 24%, depending on the total pressure of the system, which can be easily calculated using an appropriate vapor-liquid equilibrium table.

10ml of toluene were added to a suitable tailed tube, maintaining nitrogen, and components (i) and (ii) were added in the appropriate amounts to prepare the desired catalytic composition. Specifically, about 1X 10 as a toluene solution was added^-3The desired amount of moles of the above metallocene complex was then introduced as 1.5 moles of MAO (Eurecene 510010T commercial product from Witco) in toluene solution (as Al) in such an amount that the resulting catalytic mixture had an aluminum/zirconium molar ratio of 3700-4000, as illustrated in Table 3. The catalyst solution thus formed is left at room temperature for a few minutes, howeverThen under an inert gas flow, through an overpressure of nitrogen. It is poured into a metal container from which it can be transferred to the reactor.

The polymerization is carried out at 40 ℃ and it is to be noted that the reaction pressure is kept constant by continuously feeding ethylene to compensate for the portion that has reacted off, after 5 minutes the feeding of ethylene is stopped, the monomer is degassed at 60 ℃ under vacuum (about 1000Pa) and the polymer is recovered after devolatilization of the monomer. The solid thus obtained is weighed and the activity of the catalyst is calculated, expressed as Kg polymer/g zirconium metal/hour (Kg)_{Polymer and method of making same}/g_zrH). The weight-average molecular weight Mw and the number-average molecular weight Mn are measured on dry, homogeneous solids, and the various C's are measured using known methods based on IR spectroscopy₃Content of monomer units (propylene) and ENB. The results are shown in Table 3.

TABLE 3 ethylene/propylene/ethylidene norbornene copolymerization

Examples	Catalyst Zr mol.. times.106Al/Zr	PTotal pressure(MPa)	ENBFeeding of the feedstock(moles％)	Activity (Kg)Polymer and method of making same/gzr.xh)	C3Polymer and method of making same(wt%)	ENBFeeding of the feedstock(wt%)	Mw	Mw/Mn
									456789	0.6 38500.6 38501.2 38500.7 37501.2 39000.6 3750	252525252228	0.40.81.61.61.61.6	485033101770218013002680	38.336.537.634.548.333.9	2.74.17.47.310.16.5	380,000260,000262,000344,000235,000572,000	2.63.02.82.42.43.7

Examples 10 to 14: copolymerization of ethylene/propylene and its terpolymerization with ENB

Using the same preformed catalyst systems as in the preceding examples 4-9, the copolymerization of ethylene/propylene and its terpolymerization with ENB were conducted, and the specific polymerization conditions and results obtained for each example are shown in Table 4 below, which sequentially provides the cited example numbers, the amount of zirconium used, the atomic ratio of aluminum to zirconium in MAO, the polymerization pressure, the initial molar concentration of Ethylidene Norbornene (ENB) in liquid propylene, the initial amount of hydrogen introduced, the activity of the zirconium-based catalyst system, C in the polymer₂，C₃Relative amounts (moles) of monomer units and ENB, mooney viscosity of the polymer measured at 100 ℃, mechanical properties of the polymer after vulcanization (for EPDM only) (ultimate tensile strength c.r.; elongation at break A.R, shore a hardness at 160 ℃).

The polymerization was carried out in a3 l pressure reactor equipped with a thermostat and a magnetic stirrer. The reactor was flushed with about 500g of liquid propylene containing about 2g of Triisobutylaluminum (TIBA) and the mixture was discharged. The reactor was then flushed with a small amount of fresh propylene and then emptied.

800g of "polymerization grade" liquid propylene were charged into the reactor together with the amount of ENB necessary to achieve the desired concentration, and then about 1ml of a 0.3mol TIBA solution in hexane, which was used only as a scavenger, was added thereto. A small amount of hydrogen was optionally added as a molecular weight regulator, and the polymerization temperature of the reactor was then raised to 45 ℃ and gaseous ethylene was subsequently introduced through a submerged tube until the desired equilibrium pressure of the liquid mixture (22-28ate) was reached with slight stirring. Under these conditions, the molar concentration of ethylene in the liquid phase is between 12 and 20%, depending on the total pressure of the system.

10ml of toluene were added to a suitable tailed tube, maintaining nitrogen, and components (i) and () were added in the appropriate amounts to prepare the desired catalytic composition. Specifically, about 10 as a toluene solution obtained in the above example 1 was added^-3The desired molar amount of the above-mentioned metallocene complex, followed by the addition of MAO, was such that the resulting catalytic mixture had an aluminum/zirconium molar ratio of 6000-7000, which is illustrated in Table 4. The catalyst solution thus formed is kept at room temperature for a few minutes and then passed under an inert gas flow through an overpressure of nitrogen. It is poured into a metal container from which it can be transferred to the reactor.

The polymerization was carried out at 45 ℃ and it should be noted that the reaction pressure was kept constant by continuously feeding ethylene to compensate for the portion which had reacted off. After 1 hour, the ethylene feed was interrupted, the residual monomer was degassed, the autoclave temperature was rapidly cooled to room temperature, the polymer was recovered, the devolatilization of the monomer was completed by calendering at about 80 ℃, the solid copolymer thus obtained was weighed and the activity of the catalyst, expressed as Kg polymer/g zirconium metal/hour (Kg)_{Polymer and method of making same}/g_zr.h)。

These copolymers were characterized by the content of monomer units measured by IR spectroscopy and various mechanical properties measured by the above-mentioned methods after vulcanization, the characteristic results and polymerization conditions of which are shown in Table 4 below.

These examples show that the catalytic systems obtained starting from the metallocene complexes of the invention are active for the preparation of ethylene/propylene elastomeric copolymers and ethylene-propylene-diene terpolymers having a high Mooney viscosity. Example 15: comparative example

Polymerization was conducted by the same equipment and procedure as in example 10 except that 1, 2-ethylene bis- (. eta.⁵-1-indenyl) zirconium dichloride (commercial WITCO) as a component of the catalytic system instead of the complex ortho-benzylidene bis- (. eta.) -of the present invention⁵-1-indenyl) zirconium dichloride, carried out under the process conditions identified in table 4 below. The copolymers thus obtained were characterized as described above, the results obtained being summarized in table 4 below.

TABLE 4 ethylene copolymerization and terpolymerization

Examples	Catalyst Zr mol.. times.106 Al/Zr	PTotal pressure(MPa)	ENBFeeding of the feedstock(moles％)	Total amount H2(mmoles)	Activity (Kg)Polymer and method of making same/gzrxh)	C3Polymer and method of making same(heavy)Volume%)	ENBFeeding of the feedstock(wt%)	Mooney (ML4 + 100)	C.R(Kg/cm2)	A.R(％)	Shore A (minutes)
												1011121314(4)15(1，2)	0.13 72000.21 69000.24 67000.43 61000.70 60000.48 9000	242424242223	--0.40.50.81.1--	0.450.450.450.451.1--	770057605560327016002800	454542432852	--3.03.04.08.5--	65(3)85958492＜10	--101n.m104n.m--	--380n.m325n.m--	--59n.m60n.m--

Note: (¹) As a comparative example; (²) The temperature is 40 ℃; (³) Measured at 125 ℃: (⁴) Feeding: 250g of propylene and 550g of propane; no examples 16-19 were measured: copolymerization of ethylene/propylene and its terpolymerization with ENB

A series of copolymeric and terpolymerised ethylene/propylene/ENB tests were carried out in a 60-liter reactor equipped with a thermostatically-regulated jacket fed with circulating water, a mechanical stirrer and a continuous feeding system of the monomers, connected by a valve at its bottom to a 600-liter stripper for devolatilization of the polymer obtained. For more effective temperature control, the reactor is equipped with a special device which continuously withdraws a portion of the gaseous phase, condenses it and returns it to the reactor in liquid form.

The composition of the reaction mixture, which maintained the liquid/vapor equilibrium, was determined every 6 minutes by using an automatic gas phase analysis system, which is the COMBUSTION ENGINEERING method, gas chromatography model 3100, equipped with a Chromosorb 10260/80 column.

The monomers and propane were introduced into the reactor with a constant temperature of 45 ℃ to a liquid volume of up to 35 l, the amounts being adjusted to give a gas-phase composition as indicated in Table 5 below. Under these conditions, the total pressure is generally maintained between 1.5 and 2.0 MPa.

The catalysts were prepared separately as toluene solutions by mixing the desired amounts of MA0 (10 wt% in toluene) and ortho-benzylidene bis- (. eta. -benzylated)⁵-1-indenyl) zirconium dichloride complex (0.1% weight/volume in toluene) in accordance with the proportions indicated in table 5.

About 4.3g (28mmol) of a solution of triisobutylaluminum in hexane (13% w/v) were introduced into the reactor as scavenger. The mixture was kept stirring for several minutes, and then the catalyst solution was introduced into the reactor using a special vessel connected to the reactor and pressurized with anhydrous nitrogen.

Then, polymerization was carried out for 1 hour while maintaining a constant temperature of 45 ℃ with further continuous feeding of the monomer so that the vapor-liquid equilibrium constant of the components was maintained at the value shown in Table 5, and finally, the contents of the reactor were discharged into a stripping column containing about 300 liters of room-temperature water, from which residual monomer and propane were removed by evaporation. The remaining aqueous suspension was filtered, the obtained polymer was dried on a calender and then characterized, the results of which are shown in table 5.

TABLE 5 copolymerization and terpolymerization of ethylene example 16171819 catalyst mmolZr 0.0040.020.010.01 Al/Zr 5000600060006000 ethylene (mol%) 33.030.128.329.5 propylene (mol%) 16.016.615.418.5 propane (mol%) 51.053.254.047.1 ENB_Initial(ml) - 150 150 250H_{2 initial}(mmol) 0.070.150.080.17 Activity (Kg)_{Polymer and method of making same}/g_zr.h) 1900 1000 1515 700C3_{Polymer and method of making same}(wt％) 27 31 29 27ENB_{Polymer and method of making same}(wt%) -3.73.57.6 intrinsic viscosity (dl/g) 1.61.42.0-Mooney (ML 1 + 4) 574082 (wt%) (¹) 31(1): example 20 was measured at 125 ℃: copolymerization of ethylene/1-hexene I) preparation of the catalyst

The polymerization catalyst solution of the present invention was prepared separately as follows: in 50ml of dry toluene, 23mg (0.048mmol) of the complex of the formula (VIII) prepared as described in example 1 above are dissolved and then, at room temperature, 3ml of a 10 wt% MAO solution in toluene (titre of Al 1.57M) are added to this mixture in such a way that the atomic ratio Al/Zr is around 100. The solution was matured by stirring at room temperature for 30 minutes and then added to the polymerization mixture. II) polymerization

900ml of toluene (distilled beforehand over sodium metal), 60ml of 1-hexene (distilled beforehand over calcium hydride, CaH)₂Upper distillation) and 1.5ml of the above 10% by weight MAO solution in toluene were introduced into a BUCHI autoclave with a 2 litre glass reactor, equipped with a propeller stirrer and a thermostatically regulated jacket, which was kept under vacuum for at least 2 hours during 3 flushes effectively with nitrogen, the autoclave being pressurized to 0.2MPa with ethylene and heated to 40 ℃.

The autoclave was depressurized and then 1.1ml of the above prepared catalyst solution were introduced in the ethylene stream in such a way that the atomic ratio of zirconium in the complex to the total aluminum contained in MAO (resulting from the sum of the introduction together with the catalyst solution and the direct introduction into the autoclave) was 2500. The autoclave was again pressurized to 2ate with ethylene and the polymerization was carried out for 30 minutes, during which the temperature was thermostatically regulated to 40 ℃ and ethylene was fed continuously in order to keep the pressure constant during the entire test. Finally, the reaction was stopped by adding 5ml of acidified methanol, the autoclave was depressurized, and the polymer was recovered by precipitation with 3 liters of acidified methanol, followed by washing with acetone and, after drying, 15g of an ethylene/1-hexene copolymer (LLDPE) were obtained having the following characteristics: number average molecular weight (Mn) is 122,000, weight average molecular weight (Mw) is 327,000 molecular weight distribution (MWD ═ Mw/Mn): 2.7 monomer units derived from 1-hexene (intercalated 1-hexene): reactive product of 8% monomer (r)₁.r₂): 0.64 yield: 330Kg_{Polymer and method of making same}/(g_zrH) example 21: copolymerization of ethylene/1-octene

An ethylene/1-octene copolymerization experiment was carried out using exactly the same procedure and starting material as in the previous example 20, but using 75ml of 1-octene instead of 60ml of 1-hexene.

Finally, after drying, 11g of an ethylene/1-octene copolymer (LLDPE) were obtained, having the following characteristics: number average molecular weight (Mn) of 164,000, weight average molecular weight (Mw) of 362,000 molecular weight distribution (MWD ═ Mw/Mn): 2.2 monomer units derived from 1-octene (inserted 1-octene): 7.3% of reactive product of monomer (r)₁.r₂): 0.45 yield: 242Kg_{Polymer and method of making same}/(g_zrH) example 22: high temperature polymerization

The polymerization test was carried out in a 1 liter adiabatic steel reactor capable of being pressurized to about 100MPa and varying in temperature from 160 to 220 ℃.

Two streams containing monomer and catalyst solution were fed separately to the reactor, the flow rate being controlled at such values that: the residence time was about 40 seconds. The conversion per channel, and consequently the temperature, is controlled and regulated by the flow rate of the catalyst solution so as to maintain the yield of polymer between 3 and 4 Kg/h.

The catalyst solution was prepared as follows: in 90ml of toluene, 550mg (1.14mmol) of o-benzylidene bis- (. eta.⁵-1-indenyl) zirconium dichloride complex, 150ml MAO solution in toluene (titer of Al =4.5M) (Al/Zr =600) was added to this mixture. The solution was stirred at room temperature for about 1 hour and diluted by adding 1800ml Isopar-L with a Zr concentration of 0.507mM in the solution feed before introduction into the reactor. The monomer-containing stream consisted of 64% v of ethylene and 46% v of 1-butene. The polymerization temperature was kept at a constant value of about 160 ℃ and the pressure was set at 80 MPa.

Under these conditions, an ethylene-butene copolymer (LLDPE) is obtained, having the following characteristics:

mn 42,000; mw 115,000; MWD is 2.7; (MFI) 0.42g/10 min; density =0.9218g/cm³(ii) a Short chain branching number 8.3/(1000C); melting point 120.1 deg.C; the catalyst activity was confirmed to be 9,200Kg_{Polymer and method of making same}/g_zr. Example 23: ionic catalysts

The following products were introduced in sequence into an autoclave of the BUCHI type with a 2 litre steel reactor, equipped with an anchor stirrer and a thermostatically-regulated jacket with liquid circulation, previously washed and dried under vacuum (0.1Pa) for at least 2 hours: 1 liter of heptane and 250g of propylene. The mixture was heated to 50 ℃ and ethylene was added through an immersion tube with stirring to bring the total pressure to 1.3 MPa.

1.0ml of a 1.2M solution of triisobutylaluminum in toluene and 4ml of 7.5X 10, with maintenance of nitrogen^-4M ortho-benzylidene bis- (. eta.⁵The (1-indenyl) zirconium dichloride solutions were added separately to suitable tailed test tubes. After keeping the solution stirred at room temperature for 15 minutes, 3ml of 1.8X 10 was added^-3M Triphenylcarbenium tetrakis (pentafluorophenyl) borate [ Ph₃C]^＋.[B(C₆F₅)₄]^－Solution in toluene, the solution obtained was immediately transferred to a vessel placed above the autoclave, which was pressed from the autoclave into the reactor by nitrogen pressure. The polymerization started almost immediately and was continued for 30 minutes, the temperature being maintained at 50 ℃ and the pressure being maintained at 1.3MPa by continuous feeding of ethylene. Finally, after degassing the residual monomers, the polymer was recovered by coagulation by adding 1 liter of methanol, filtered, and then dried, thus obtaining 90.5g of an ethylene/propylene copolymer having a content of propylene units of 26.9 wt%, an Mn average molecular weight of 100,000, and an Mw/Mn dispersion of 1.8. The activity of the catalyst is 332Kg_{Polymer and method of making same}/g_zr。

Claims (23)

1. A metallocene complex useful in forming a catalyst for the (co) polymerization of ethylene with α -olefins, having the formula:(II) wherein: m represents a metal selected from titanium, zirconium or hafnium;

each A 'or A' independently represents an organic radical containing an anionic character eta coordinated to the metal M⁵-a cyclopentadienyl ring;

each R 'or R' independently represents a group of anionic character sigma-bonded to the metal M;

b represents an unsaturated divalent organic residue having 1 to 30 carbon atoms, which is bonded to the ring of the group A' and to the-CH, respectively, by means of an unsaturated atom other than hydrogen₂-on the methylene group.

2. The complex of claim 1 wherein at least one, preferably both, of a' and a "are selected from η⁵-indenyl or η⁵- (4, 5, 6, 7-tetrahydro) indenyl,

3. The complex of any one of claims 1 or 2 wherein the metal M is zirconium.

4. The complex of any preceding claim wherein the divalent organic residue "B" is selected from ortho-phenylene having 6 to 20 carbon atoms, or peri-naphthylene having 10 to 20 carbon atoms.

5. The complex of any preceding claim wherein each R' or R "group having formula (II) is independently selected from hydride, halide, C₁-C₂₀Alkyl or alkylaryl radicals, C₃-C₂₀Alkylsilyl group, C₅-C₂₀Cycloalkyl radical, C₆-C₂₀Aryl or arylalkyl, C₁-C₂₀Alkoxy or thioalkoxy radical, C₁-C₂₀Carboxylates or carbamates, C₂-C₂₀Dialkylamido and C₄-C₂₀An alkylsilylamide group.

6. A catalyst for the (co) polymerization of ethylene with other alpha-olefins, comprising at least the following two components in contact with each other;

at least one metallocene complex according to any of the preceding claims 1 to 5,

(ii) a cocatalyst consisting of at least one organic compound of an element M 'different from carbon, wherein the element M' is selected from the elements of groups 2, 12, 13 or 14 of the periodic Table.

7. The catalyst of claim 6 wherein said component (i) consists of the metallocene complex of the preceding claim 4.

8. The catalyst according to claim 6 or 7, wherein the element M' in component (ii) is selected from boron, aluminium, zinc, magnesium, gallium and tin, more particularly boron and aluminium.

9. A catalyst according to any preceding claim, wherein the component (ii) is a polymeric aluminoxane, preferably methylaluminoxane.

10. The catalyst as claimed in claim 9, wherein the atomic ratio of metal M in the complex of the formula (II) to Al in the aluminoxane is 100-5000.

11. The catalyst of any of claims 6 to 8, wherein the component (II) consists of at least one organometallic compound of M 'or a mixture thereof, which is capable of reacting with the complex of formula (II) to extract the sigma-bonded R' or R 'groups therefrom, on the one hand forming at least one neutral compound and on the other hand forming an ionic compound consisting of the metallocene cation containing the metal M and the non-coordinating organic anion containing the metal M'. Their negative charge is off the multicenter structure.

12. The catalyst of claim 11 wherein the atomic ratio of metal M' in fraction (ii) to metal M in component (i) is from 1 to 6.

13. The catalyst of claim 11 or 12, wherein the component (ii) consists of an ion-ionizing compound. Selected from compounds having the formula: [ (R)_C)_XNH_4－X]^＋×[B(R_D)₄]^－；B(R_D)₃；[Ph₃C]^＋×[B(R_D)₄]^－；[(RC)₃PH]^＋×[B(R_D)₄]^－；[Li]^＋×[B(R_D)₄]^－；[Li]^＋×[Al(R_D)₄]^－；

Wherein subscript "X" is an integer of from 0 to 3;

each R_CThe radicals independently represent an alkyl or aryl radical having 1 to 10 carbon atoms, each R_DThe radicals independently represent partially or preferably partially fluorinated, aromatic radicals having 6 to 20 carbon atoms

14. The catalyst of claim 13, wherein, in addition to the ion-ionizing compound, the component (ii) comprises the formula AlR_mX_3-mWherein R is linear or branched C₁-C₈Alkyl, X is chlorine or bromine, "m" is a decimal number between 1 and 3, preferably 3, and the ratio of B or Al in the ion-ionizing compound to Al in the aluminum alkyl is 100/1 to 500/1.

15. A process for the (co) polymerization of ethylene or α -olefins, which can be continuous or batch, in one or more stages, comprising a low pressure (0.1-1.0MPa), a medium pressure (1.0-10MPa) or a high pressure (10-150MPa), at a temperature of 20 to 240 ℃, optionally in the presence of an inert diluent, characterized in that at least ethylene or at least one α -olefin is brought into contact with a catalyst according to any one of the preceding claims 6 to 14, under one of the above-mentioned conditions.

16. The process of claim 15 wherein ethylene is copolymerized with at least one α -olefin having from 3 to 10 carbon atoms.

17. The process of claim 16 wherein an aliphatic or alicyclic nonconjugated diene having 5 to 20 carbon atoms is copolymerized with ethylene in addition to the at least one α -olefin.

18. Process according to any of the preceding claims 15 to 17, characterized in that the solution or suspension polymerization is carried out in a suitable inert liquid medium having the composition: aliphatic or cycloaliphatic hydrocarbons having from 3 to 15 carbon atoms, or mixtures thereof.

19. Process according to any of the preceding claims 15 to 17, characterized in that it is carried out in the absence of an inert diluent.

20. The process as claimed in any of claims 15 to 19, characterized in that the concentration of the metal M in the formula (II) in the polymerization mixture is 10^-5-10^-8Mol/l.

21. A biscyclopentadienyl compound useful as a ligand to form a complex of formula (II) of claim 1, having the following general formula (IV):

HA″—CH₂-B-A 'H (IV) in which B represents an unsaturated divalent organic residue having 1 to 30 carbon atoms, bonded to the ring of the group A' and to the-CH, respectively, by means of unsaturated atoms other than hydrogen₂-on the methylene group, each a' H or a "H group independently represents a neutral organic group containing a cyclopentadienyl ring which may be represented by the following formula (IV-bis):(IV-bis) wherein each substituent R₁，R₂，R₃And R₄Independently represents hydrogen. Halogen, aliphatic or aromatic C₁-C₂₀Hydrocarbyl, optionally comprising one or more heteroatoms different from carbon and hydrogen, especially F, Cl, O, S and Si, or, adjacent R₁，R₂，R₃And R₄Wherein at least any two substituents are linked to form a saturated or unsaturated C₄-C₂₀A cyclic structure comprising the bond of the cyclopentadienyl ring, which structure optionally contains one or more of the above-mentioned heteroatoms, and a ring system in the center of the ringThe illustrated hydrogen atom is then bonded to any carbon atom in the cyclopentadienyl ring, and the virtual ring is briefly represented as two bi-conjugated bonds at the remaining 4 atoms of the cyclopentadienyl ring.

22. The biscyclopentadienyl compound of claim 21, characterized by the following formula (V):

HA″—CH₂—B′—A′H (V)

wherein each A 'H or A' H group independently represents a neutral organic group containing a cyclopentadienyl ring, which may be represented by the following formula (IV-ter):(IV-ter)

wherein each substituent R₁，R₂，R₃And R₄Independently represents hydrogen. Halogen, aliphatic or aromatic C₁-C₂₀Hydrocarbyl, optionally comprising one or more heteroatoms different from carbon and hydrogen, in particular F, Cl, O, S and Si, or,

adjacent R₁，R₂，R₃And R₄Wherein at least any two substituents are linked to form a saturated or unsaturated C₄-C₂₀A cyclic structure comprising a bond to the cyclopentadienyl ring, which structure optionally contains one or more of the above heteroatoms, with the proviso that A' H is different from fluorenyl or substituted fluorenyl, the hydrogen atom represented at the center of the ring is randomly bonded to any carbon atom in the cyclopentadienyl ring,

the dotted ring is briefly represented as two bi-conjugated bonds on the remaining 4 atoms of the cyclopentadienyl ring.

B' represents a divalent organic group having 6 to 30 carbon atoms and comprising a benzene aromatic ring, the two valency bonds of which are in adjacent positions to the aromatic ring.

23. A process for the preparation of biscyclopentadienyl compounds of formula (V) according to claim 22, characterized in that it comprises the following steps in succession:

a) having the formula HO-CH₂The alcohol radical of o-bromobenzyl alcohol of-B' -Br by reaction with an enol-alkyl ether R having from 3 to 10 carbon atoms⁶-O-CR⁷＝CH₂By reaction, wherein B' is as defined above for formula (V), R⁶＝C₁-C₆Alkyl radical, R⁷Hydrogen or C₁-C₆Alkyl, reacted in catalytic amounts with an aprotic Lewis acid, preferably POCl₃In the presence of a catalyst to form the corresponding gem-diether Br-B' -CH₂-O-CR⁷(CH₃)-O-R⁶；

b) Metallation of the geminal diether obtained in step (a) with a lithium or magnesium alkyl compound having 1-10 carbon atoms, carried out in a non-polar solvent at a temperature of 0-30 ℃ by substitution of the bromine atom to obtain the corresponding lithium or magnesium salt (Li or Mg) -B' -CH₂-O-CR⁷(CH₃)-O-R⁶；

c) The salt thus obtained is condensed with an-a' H precursor consisting of cyclopentenone having the corresponding structure, with the carbonyl oxygen on the carbon bonded to the magnesium or lithium salt in the ring position, the reaction is carried out in an aprotic polar solvent, preferably THF, at a temperature of less than-30 ℃, preferably-50 to-100 ℃, and then the compound (V-bis) having the formula is obtained by hydrolysis of the reaction product with removal of water:(V-bis)

or preferably by addition of an-OH group to the double bond alpha in B' to obtain the corresponding bicyclic helix derivative;

wherein the various symbols B', R₁，R₂，R₃And R₄All have the same definitions as above;

d) a compound having the formula (V-bis); or (c) reacting the corresponding helical derivative obtained in step (c) with an excess of aqueous hydrochloric or hydrobromic acid at a temperature of 50-130 ℃ to obtain an o-cyclopentadienyl benzyl halide having the same structure as the compound of formula (V-bis), wherein the difference is only that the-OH group is replaced by a corresponding-Cl or-Br halide;

e) reacting the cyclopentadienyl benzyl halide obtained in step (d) with a compound of formula HA' (Li or M)gR⁸) Wherein A' has the same definition as in formula (V), R⁸Selected from Cl, Br or A' in a suitable solvent, preferably a THF/hexane mixture, at a temperature of 10 to 40 ℃ to obtain the desired ligand.