HK1015791B - Metallocenes, their preparation and use in the polymerization of alphaolefins - Google Patents

Description

Metallocenes, method for the production thereof and use thereof for the polymerization of α -olefins

The invention relates to a catalytic component of the metallocene type and to the preparation thereof, in the optional presence of a diene, of C₂-C₂₀(Co) polymers of olefins, in particular ethylene with C₃-C₂₀Preferably C₃-C₁₀More preferably C₃Use of a copolymer of α -olefins.

Metallocenes containing cyclopentadienyl derivatives as ligands are known as catalytic components in the preparation of olefin (co) polymers. For example, EP-A-185.918 discloses ｃA process for preparing isotactic polypropylene in the presence of ｃA catalytic system comprising an aluminoxane and ethylene bis (4, 5, 6, 7-tetrahydro-1-indenyl) zirconium dichloride.

U.S. Pat. No. 3, 5.268.495 discloses A novel process for preparing metallocenes bridged to cyclopentadienyl rings. According to this document, bridged metallocenes containing cyclopentadienyl derivatives as ligands have interesting properties and are capable of (co) polymerizing a wide range of olefins.

It has now been found that novel metallocenes are capable of (co) polymerizing C, optionally in the presence of a diene₂-C₂₀Olefins, especially copolymerisation of ethylene with C₃-C₂₀Preferably C₃-C₁₀More preferably C₃α -olefins.

The (co) polymers thus obtained may have a broad molecular weight, may or may not be elastic, and thus can be applied to various fields.

Accordingly, the present invention relates to a process for the copolymerization of ethylene with C in the optional presence of a diene₃-C₂₀Preferably C₃-C₁₀More preferably C₃α -olefin, said catalytic component having the following general formula (I):wherein: a is a cyclopentadienyl derivative containing general formula (II)

Wherein R is₁And R₂Selected from H and C₁-C₃Alkyl, preferably R₂H and two R₁Is H; n is a positive integer from 2 to 18, preferably from 3, 5, 6 and 10;

b is selected from: 1) any one of the cyclopentadienyl derivatives a defined above; 2) a monofunctional cyclopentadienyl group (F) selected from the group consisting of cyclopentadienyl, indenyl, fluorenyl, and corresponding alkyl, aryl, trialkylsilyl substituted derivatives;

the bridge Q between A and B is a bifunctional group selected from: a) c₁-C₂₀Linear, branched, cyclic alkylene; b) a silylene or disilylene alkyl substituted group; c) alkyl-substituted silalkylene;

m is selected from titanium, zirconium, hafnium, vanadium, niobium, preferably zirconium;

x is selected from halogen, hydrogen, C₁-C₁₀Alkyl radical, C₁-C₁₀Alkoxide group, C₂-C₂₀Amide group, C₂-C₂₀Carboxyl group, C₆-C₁₀Aryl radical, C₆-C₁₀Aryloxy radical, C₂-C₁₀Alkenyl radical, C₇-C₄₀Aralkyl radical, C₇-C₄₀Alkylaryl group, C₈-C₄₀Aralkenyl, preferably C₁-C₃Alkyl or halogen, preferably chlorine.

The bridged ligands A-Q-B and their preparation have been disclosed in Italian pending patent application IT-A-MI 95/002284 filed by the same applicant.

Some examples of compounds of general formula (I) are shown in FIG. 1.

In particular, the compounds belonging to formula (I) and given in FIG. 1 are: dimethylsilyl-bis (4, 5, 6, 7, 8-pentahydroazulen-2-yl) zirconium dichloride (CP136A, example 1.1 in fig. 1); [1- (3-methyl-inden-1-yl) -1-methyl-ethyl-4, 5, 6, 7, 8-pentahydroazulen-2-yl]zirconium dichloride (CP172, example 1.2 in FIG. 1); [1- (inden-1-yl) -1-methyl-ethyl-4, 5, 6, 7, 8-pentahydroazulen-2-yl]zirconium dichloride (CP138E, example 1.3 in FIG. 1); dimethylsilyl-bis (4, 5, 6, 7, 8, 9, 10, 11, 12, 13-decahydrocyclopentano-cyclododecen-2-yl) zirconium dichloride (CP192, example 1.4 in fig. 1); 1, 2-bis (4, 5, 6, 7, 8-pentahydroazulen-2-yl) -tetramethyldisilyl-zirconium dichloride (CP191C, example 1.5 in fig. 1); 1- [4, 5, 6, 7, 8-pentahydroazulen-2-yl]-2- [ 3-methyl-indenyl-1-yl]-tetramethyldisilyl-zirconium dichloride (CP266E, example 1.6 in fig. 1);

in one embodiment, Q is a linear, branched or cyclic alkylene group containing from 1 to 20 carbon atoms. Typical examples are: methylene, ethylene, propylene, butylene, pentylene, hexylene, isopropylene (CH)₃-C-CH₃) Isobutylene (CH)₃-C-C₂H₅)，(C₂H₅-C-C₂H₅)。

In another embodiment, Q is a silylene or disilylene alkyl substituted group, such as dimethylsilylene, or-Si (CH)₃)₂-, tetramethyldisilylene, or-Si (CH)₃)₂-Si(CH₃)₂-methylethylsilylene, diethylsilylene.

In yet another embodiment, the Q group consists of a silicon-carbon sequence, i.e., a sila-alkylene alkyl substituted group, such as-Si (R')₂-C(R″)₂-, wherein R 'is a lower alkyl group and R' is hydrogen or a lower alkyl group. Typical examples of sila-alkylenes are: 1-sila-1, 1-dimethylethylene; 2-sila-2, 2-dimethylpropylene; 1, 3-disiloxa-1, 1, 3, 3-tetramethylpropylene.

In a preferred embodiment, Q is selected from branched alkylene, dialkylsilylene derivatives, more preferably from isopropylidene, dimethylsilylene and tetramethyldisilylene.

In the case where B is any group (A) as defined for formula (II), in the product of formula (I) the group Q forms a bridge comprising two cyclopentadienyl derivatives connected to Q in the 2-position of the cyclopentadienyl ring.

When B is a derivative (F) different from (A), it is a monofunctional cyclopentadienyl group selected from the group consisting of cyclopentadienyl, indenyl, fluorenyl and the corresponding alkyl, aryl, trialkylsilyl substituted derivatives; in a preferred embodiment, (F) is selected from the group consisting of cyclopentadienyl, indenyl and fluorenyl. For simplicity, we will refer to these compounds as A-X-C.

In the case where B is chosen from the group F, the point of attachment of the above derivative to the bridge Q is well known to the skilled person, for example, the indenyl group itself will be bonded to Q from the 1 position, while the fluorenyl group will be bonded to Q from only the non-fused position of the ring containing 5 chain ends.

The invention also relates to a process for the preparation of metallocenes of the general formula (I), which comprises reacting a compound of the general formula HA-Q-BH, in which Q, A and B have the meanings defined above, with a metal alkyl, preferably an alkyllithium, to give the corresponding dianion, which is then reacted with MX₄Preferably zirconium tetrachloride, to give the compounds of the general formula (I). Elucidation of butyl lithium and ZrCl₄The reaction scheme of (a) is as follows:

another subject of the invention relates to a process for preparing C in the presence of an optional diene₂-C₂₀α homopolymerization and copolymerization of olefins, especially ethylene and C₃-C₁₀α -Process for the copolymerization of olefins, more preferably propylene, using a catalytic system comprising a compound of formula (I).

In the α -olefin (co) polymerization, the catalytic system comprises, in addition to the metallocene of the formula (I), another component (known as cocatalyst) chosen from aluminoxanes and those of the formula (III) (Ra)_xNH_4-xB(Rd)₄Or of the general formula (IV) (Ra)₃PHB(Rd)₄Or of the formula (V) B (Rd)₃Or a compound of the formula (VI) CPh₃[B(Rd)₄]Which is capable of generating an ionic catalytic system by reaction with a metallocene of the general formula (I). In the compounds of the above formula (III), (IV), (V) or (VI), the same or different Ra groups are monofunctional alkyl or aryl groups and the same or different Rd groups are monofunctional aryl groups, preferably partially or fully fluorinated, more preferably fully fluorinated. When compounds of the formula (III), (IV), (V) or (VI) are used, the catalyst system consists essentially of the reaction product of any one of the compounds of the formula (III), (IV), (V) or (VI) or a mixture thereof of one or more metallocenes of the formula (I) in which X is H or a hydrocarbon radical, as described in EP-A277.007, wherein the molar ratio between the compound of the formula (III), (IV), (V) or (VI) and the metallocene of the formula (I) is from 0.1 to 19, preferably from 0.5 to 6, more preferably from 0.7 to 4.

In the compounds of formula (I), when X is a non-hydrogen or non-hydrocarbyl group, the catalytic system consists of one or more metallocenes of formula (I), an alkylate (VII) selected from trialkylaluminium, dialkylmagnesium, or alkyllithium or other alkylating agents known to those skilled in the art, and any compound of formula (III), (IV), (V) or (VI), or mixtures thereof.

The step of forming the catalytic system comprises premixing the metallocene compound of formula (I) with a suitable alkylating agent (VII) in an aliphatic or aromatic hydrocarbon solvent or a mixture thereof at a temperature ranging from-20 ℃ to +100 ℃, preferably from 0 ℃ to 60 ℃, more preferably from +20 ℃ to +50 ℃ for a period ranging from 1 minute to 24 hours, preferably from 2 minutes to 12 hours, more preferably from 5 minutes to 2 hours. This mixture is then brought into contact with the compound of the formula (III), (IV), (V) or (VI) at the abovementioned temperatures for between 1 minute and 2 hours, preferably between 2 minutes and 30 minutes, and is then introduced into the polymerization reactor.

The molar ratio between the alkylate (VII) and the compound of formula (I) may be from 1 to 1000, preferably from 10 to 500, more preferably from 30 to 300.

The molar ratio between the compound of the formula (III), (IV), (V) or (VI) and the metallocene (I) can be from 0.1 to 10, preferably from 0.5 to 6, more preferably from 0.7 to 4.

As regards the aluminoxane, it is an aluminum-containing compound of the general formula (VIII) when it is linear,

(R^e)₂-Al-O-[-Al(R^e)-O-]_p-Al(R^e)₂(VIII) when cyclic, has the general formula: (IX) - [ -O-Al (R)^e)-]_p+2Wherein the same or different variables R^eIs selected from C₁-C₆Alkyl radical, C₆-C₁₈Aryl, or H, "P" is an integer from 2 to 50, preferably from 10 to 35. Variable R^ePreferably identical, from the group consisting of methyl, isobutyl, phenyl or benzyl, preferably methyl.

When variable R^eWhen different, methyl and hydrogen or methyl and isobutyl are preferred, hydrogen or isobutyl as R^eThe radicals are preferably present in an amount of from 0.01 to 40% by weight.

Aluminoxanes can be prepared using various methods known to those skilled in the art. For example, one of the processes comprises reacting a trialkylaluminum compound and/or a dialkylaluminum monohydride with water (gaseous, solid, liquid or critical, for example water of crystallization) in an inert solvent such as toluene. To prepare compounds having different R^eAlkyl aluminoxane, two different trialkylaluminums (AlR)₃+AlR′₃) Reacted with water (see S.Pasynkiewicz, Polyhedron 9(1990)429-430 and EP-a-302.424).

The exact structure of the aluminoxane is not known.

The metallocene may be preactivated with alumoxane prior to use in the polymerization stage. This greatly increases the polymerization activity. The preactivation described above is preferably carried out by dissolving the metallocene in an inert hydrocarbon solution, preferably an aliphatic or aromatic hydrocarbon, more preferably toluene. The concentration of the aluminoxane in the solution is from 1% by weight to its saturation value, preferably from 5 to 30% by weight, based on the entire solution. The metallocene can be used in the same concentration, butin an amount of 10 per mole of aluminoxane^-4-1 mole. The preactivation is carried out for 5 minutes to 60 hours, preferably 50 minutes to 60 minutes. The temperature is-78 deg.C-100 deg.C, preferably 0 deg.C-70 deg.C.

The catalytic system of the invention (catalyst and cocatalyst of general formula I) can be prepared by contacting the procatalyst with the cocatalyst, either inside or outside the reactor, in the presence or absence of the monomer to be polymerized.

The amounts of the main catalyst and the cocatalyst are not particularly limited. For example, in the case of slurry polymerization, the catalyst concentration is preferably 10^-8-10^-1Mol/liter, more preferably 10^-7-10^-5Moles per liter (based on transition metal M). When an aluminoxane is used, the molar ratio between aluminum and the transition metal M is preferably more than 10 and less than 10,000.

In addition to the procatalyst and cocatalyst, the catalyst system may comprise a third optional component, usually one or more substances containing active hydrogen atoms, such as water, alkanols (e.g.methanol, ethanol, butanol), or electron donor compounds, such as ethers, esters, amines, alkoxy-containing compounds, such as phenyl borate, dimethylmethoxyaluminum, phenyl phosphate, tetraethoxysilane, diphenyldimethoxysilane.

The main catalyst and the cocatalyst may be added to the reactor separately or after having been previously contacted with each other. In the latter case, the mutual contact can be carried out in the presence of a monomer to be polymerized, thus carrying out a so-called "prepolymerization".

In the case of the polymerization process, it is then advantageous to eliminate catalyst poisons which may be present in the monomers, in particular propylene. In this case, the purification may be carried out with an alkylaluminum such as AlMe₃，AlEt₃，Al(iso-Bu)₃Is carried out. The purification can be carried out in the polymerization system itself, or the monomers are brought into contact with an aluminum alkyl before the polymerization and subsequently separated off.

The catalytic system of the invention is used in slurry phase polymerization (where an inert medium such as propane or butane is used as suspending agent, or the suspending agent may be propylene itself or its corresponding mixture), gas phase polymerization and solution polymerization. It is clear that the catalyst of the invention can be used for continuous or batch polymerizations.

When the polymerization is carried out in a solvent, the aliphatic and aromatic hydrocarbons may be conveniently used as diluents, either alone or in admixture with one another.

Suitable processes for loading the metallocene component on porous solids such as silica and alumina in the presence of possible cocatalysts are well known in the literature.

The polymerization temperature is about-78 ℃ to 200 ℃, preferably-20 ℃ to 100 ℃. The pressure of the olefin in the reaction system is not particularly limited, although it is preferably from atmospheric pressure to 5 MPa.

The molecular weight during the reaction can be controlled by any known method, such as by appropriately selecting the polymerization temperature and pressure, or by introducing hydrogen.

The olefins which can be polymerized by the process of the present invention are α -olefins (including ethylene) having from 2 to 20 carbon atoms, preferably from 2 to 10 carbon atoms typical examples of α -olefins which can be (co) polymerized by the process of the present invention are ethylene, propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene and 1-eicosene.

As is known to those skilled in the art, it is possible to react with α -olefins, in particular with C₂-C₃The olefin copolymerized diolefin is selected from: linear dienes, such as 1, 4-hexadiene and 1, 6-octadiene; acyclic dienes with branched chains, such as 5-methyl-1, 4-hexadiene, 3, 7-dimethyl-1, 6-octadiene, 3, 7-dimethyl-1, 7-octadiene, dihydromyrcene, and dihydroocimene; monocyclic alicyclic dienes, such as 1, 4-cyclohexadiene, 1, 5-cyclooctadiene, 1, 5-cyclododecadiene; alicyclic bridged cyclodiolefins, such as methyltetrahydroindene, dicyclopentadiene, bicyclo (2, 2, 1) hepta-2, 5-diene, alkenyl, alkylidene, cycloalkenyl and cycloalkylidene norbornenes, e.g. 5-methylene-2-norbornene (MNB), 5-ethylidene-2-norbornene (ENB), 5-propenyl-2-norbornene, 5-isopropenyl-2-norbornene, 5-cyclolideneHexyl-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; the most preferred third monomer is 5-ethylidene-2-norbornene (ENB).

When preparing EPDM, the diene content of the polymer is less than 15% by weight, preferably from 2 to 10% by weight, with the propylene content being as defined above.

More particularly, a further object of the present invention relates to a process for preparing ethylene/α -olefin copolymers or ethylene/α -olefin/diene terpolymers, preferably ethylene-propylene (EPM) or ethylene-propylene-diene (EPDM), in a slurry phase, wherein the propylene content is from 10 to 75% by weight, preferably from 15 to 70% by weight, which comprises the steps of 1) feeding a α -olefin, optionally diluted with a hydrocarbon, and possibly a diene, to a polymerization reactor at a pressure such that the α -olefin is liquid, 2) adding a sufficient amount ofethylene to the mixture obtained in step (1) to maintain the desired ethylene/α -olefin ratio in the liquid phase, 3) optionally in the presence of an alkylate (VII), adding a catalytic system comprising one or more metallocenes and one or more cocatalysts selected from the group consisting of aluminoxanes (III) (Ra)_xNH_4-xB(Rd)₄Or (IV) (Ra)₃PHB(Rd)₄Or (V) B (Rd)₃Or (VI) CPh₃[B(Rd)₄]4) the mixture obtained in step (3) is reacted for a time sufficient to polymerize an ethylene/α -olefin system with possible diolefins, characterized in that the catalytic system comprises a metallocene chosen from the following general formulae (I):wherein: the meanings of A, B, Q, M, X are as defined above.

When preparing EPDM, the diene content of the polymer is less than 15% by weight, preferably from 2 to 10% by weight, with the propylene content being as defined above.

EP (D) M is prepared by polymerizing ethylene with α -olefins, preferably propylene, and possibly diolefins (optionally with hydrocarbons, preferably of low boiling point C) in a slurry phase₃-C₅A hydrocarbon, more preferably propaneAlkane dilution). A catalytic system is suspended in this mixture, the composition of which is: a metal of the formula (I)Metallocenes and cocatalysts selected from MAO and compounds of the general formulae (III) to (VI) and possibly alkylates (VII). The catalytic system is maintained in an amount to produce a sufficient amount of polymer including possible diolefins.

The possible diene concentrations in the reactor are between 0.05 and 10%, preferably between 0.2 and 4%, in volume percent.

One embodiment of the slurry process of the present invention is described below:

liquid propylene is continuously fed into a stirred reactor together with ethylene and possibly diolefins, optionally with a low boiling point C₃-C₅And (5) diluting the hydrocarbon. The reactor contains a liquid phase consisting essentially of liquid propylene, possibly diene monomer, and optionally a low boiling hydrocarbon in which gaseous ethylene is dissolved, and a vapor phase comprising all of the component vapors. The ethylene feed is either passed as a gas into the gas phase of the reactor or dispersed in the liquid phase, as is known to those skilled in the art.

The components of the catalytic system (catalyst, cocatalyst, optionally alkylate and a possible scavenger) can be introduced into the reactor in the gas or liquid phase, preferably in the liquid phase, through additional valves.

The polymerization is carried out in the liquid phase, obtaining a copolymer soluble or insoluble in this phase, the residence time of the suspension in the reactor being between 10 minutes and 10 hours, preferably between 30 minutes and 2 hours; longer residence times result in a final polymer with a low content of catalyst residues.

The reactor temperature can be controlled by cooling the reactor by means of coils or jackets in which a cooling liquid is circulated, or more preferably by evaporating and condensing α -olefins (and possibly low-boiling hydrocarbons) and returning them back to the reactor.

The ethylene content of the polymer depends on the ratio of the partial pressure of ethylene to the total pressure in the polymerization reactor, the partial pressure of ethylene is generally maintained between 0.5 and 50 bar, preferably between 1 and 15 bar, the temperature of the reactor is maintained between-10 ℃ and 90 ℃, more preferably between 20 ℃ and 60 ℃ under these operating conditions, the ethylene,α -olefin and possibly diolefin are polymerized to obtain an EP (D) M copolymer.

The work-up of the reaction mixture depends on the molecular weight of the copolymer produced, and in fact, the process of the invention makes it possible to obtain copolymers of different molecular weights (depending on the operating conditions, and in particular on the metallocene used in the polymerization), and therefore can be applied in a wide range of fields.

M_wUp to a value of 10⁵Can be used, for example, to produce a copolymer having dispersed and viscous phase characteristics or bothBoth have bases for lubricating oil and gasoline additives.

For high M_wValues, corresponding to Mooney viscosities (ML1+4) greater than 25, the copolymers and terpolymers of the present invention can be applied to structures having cured end products, such as pipes, seals, cable coatings, and other items of technology, using well known formulations, such as crosslinking agents, peroxides (in the case of copolymers) or sulfur-containing accelerators (in the case of terpolymers).

For a better understanding of the present invention, the following examples are provided.

Example 1 synthesis of dimethylsilyl-bis (4, 5, 6, 7, 8-pentahydroazulen-2-yl) zirconium dichloride (CP 136A).

8.5ml (0.0136 mol) of 1.6M LiMe in ether were added at room temperature to a solution of 2.2 g (0.0068mol) of bis- (2, 4, 5, 6, 7, 8-h mutexahydroazulen-2-yl) dimethylsilane, the preparation of which is disclosed in mutexample 1 of Italian patent application IT-A-MI 95/002284, dissolved in 100ml of ether. The mixture was stirred for 4 hours, then cooled to-70 ℃ and 1.8 g (0.0077 mol) of ZrCl were added₄. Thereafter, the temperature was raised to room temperature and further stirred for 2 hours, and then the mixturewas filtered and washed with diethyl ether and then hexane. Extraction with dichloromethane, concentration and filtration. The solid was washed with a small amount of dichloromethane, then with hexane and finally dried to give 0.4 g of the complex (12% yield of ligand used).¹H NMR(CDCl₃δ ppm vs TMS): 5.38(s, 4H); 2.8(m, 8H); 2.0(m, 8H); 1.65(m, 4H); 0.81(s, 6H).¹³CNMR(CDCl₃δ vs TMS): -4.49; 29.26; 31.30, respectively; 32.60 parts of; 101.60；115.50；143.16.

Example 2 synthesis of [1- (3-methyl-inden-1-yl) -1-methyl-ethyl]-4, 5, 6, 7, 8-pentahydroazulen-2-yl zirconium dichloride (CP 172).

0.3 g of t-BuOK was added to a mixture of 4.5 g (0.0336 mol) of 2, 4, 5, 6, 7, 8-h mutexahydroazulene, 70ml MeOH and 10ml acetone as disclosed in mutexample 1 of Italian patent application IT-A-MI95/002707, which was prepared and maintained at reflux for 20 h. An additional 2.7 g of t-BuOK was added and the reflux was maintained for an additional 25 hours. Finally the mixture was poured into water and extracted with ether. After neutralization and drying, the ether extracts were evaporated and the residue was purified by elution on a silica gel column using petroleum ether to give 3.8 g of a yellow solid (65% yield) of the methylenecyclopentadiene derivative 2-isopropylidene-2, 4, 5, 6, 7, 8-hexahydroazulene.

At room temperature, 12.4ml of a 2.5M solution of LiBu in hexane are added to an ether solution of 4.2 g (0.032 mol) of 1-methylindene in 100ml of diethyl ether. The mixture was stirred for 3 hours, then 3.8 g (0.022 moles) of 2-isopropylidene-2, 4, 5, 6, 7, 8-hexahydroazulene were added at-70 ℃. The temperature was raised and the mixture was stirred for 48 hours. The reaction mixture was hydrolyzed in water, extracted with ether, evaporated and purified on a silica gel column using petroleum ether as eluent to obtain a solid. 4.5 g (0.0148 mol) of 2- [1- (3-methyl-1H-inden-1-yl) -1-methyl-ethyl are prepared]1, 4, 5, 6, 7, 8-hexahydroazulene, which was dissolved in 200ml of diethyl ether, 18.8ml of a 1.6M solution of LiMe in diethyl ether were added and the mixture was stirred overnight to form a yellowish precipitate. After cooling the mixture to-70 ℃ 3.51 g (0.015 mol) of zirconium tetrachloride were added. When the temperature is raised to room temperature, the material tends to be dark brown-yellow. The mixture was filtered, washed with diethyl ether and gradually turned yellow, then extracted with dichloromethane (2X 100 ml). The solution is concentrated and 20ml of diethyl ether are added. The solid precipitate was filtered, washed with ether and then hexane and dried to obtain 1.0 g of the complex. After two days, a large amount of orange crystals were separated from the yellow diethyl ether mother liquor, then filtered and washed with hexane to obtain 2.1 g of pure complex (depending on the used one) of 3.1 g total45% yield calculated for ligand).¹H NMR(CDCl₃δ ppm vs TMS): 7.55(d, 2H); 7.25(m, 1H); 6.95(m, 1H); 5.65(s, 1H); 5.43(d, 1H); 2.8-2.5(m, 4H); 2.45(s, 3H); 1.9-1.6(m, 7H); 1.40(m, 2H).

Example 3 synthesis of [1- (indenyl-1-yl) -1-methyl-ethyl]-4, 5, 6, 7, 8-pentahydroazulen-2-yl zirconium dichloride (CP 138E).

3.5 g (0.0121 mol) of 2- [1- (1H-indenyl-1-yl) -1-methylethyl radical, the preparation of which is as disclosed in mutexample 2 of Italian patent application IT-A-MI95/A002284]-1, 4, 5, 6, 7, 8-hexahydroazulene was dissolved in 200ml of ether and 15.2ml of 1.6mli me solution in diethyl ether were added at room temperature. After the addition the mixture was stirred overnight to form a yellowish precipitate. After cooling the mixture to-70 ℃ 2.83 g (0.0121 mol) of solid zirconium tetrachloride were added. When the temperature is raised to room temperature, the material tends to be dark brown-yellow. The mixture was filtered, washed with diethyl ether and gradually turned yellow, then extracted with dichloromethane (2X 100 ml). The solution was concentrated and 20ml were addedDiethyl ether. The solid precipitate was filtered, washed with ether and then hexane and dried to obtain 0.8 g of complex. After two days, a large amount of orange crystals were separated from the yellow diethyl ether mother liquor, then filtered and washed with hexane to obtain 1.6 g of pure complex (0.0053 mol, 44% yield) in a total of 2.4 g.¹H NMR(CDCl₃δ ppm vs TMS): 7.59(m, 2H); 7.30(m, 1H); 7.05(m, 1H); 6.90(d, 1H); 6.00(d, 1H); 5.42(d, 1H); 5.25(d, 1H); 2.60(m, 4H); 2.51(s, 3H); 1.86(S, 3H); 1.80(m, 4H); 1.40(m, 2H).

Example 4 synthesis of dimethylsilyl-bis (4, 5, 6, 7, 8, 9, 10, 11, 12, 13-decahydrocyclopentano-cyclododecen-2-yl) zirconium dichloride (CP 192).

2.2 g (0.0047 mol) of bis- (4, 5, 6, 7, 8, 9, 10, 11, 12, 13-decahydro-2H-cyclopentacyclododecen-2-yl) dimethylsilane, the preparation of which is disclosed in mutexample 3 of Italian patent application IT-A-MI95/002707, are dissolved in 50ml of diethyl ether, 5.9ml of a 1.6M ether solution of LiMe are added, the mixture is stirred for 1.5 hours, cooled to-70 ℃ and 1.1M LiMe is addedGrams (0.0047 moles) of solid zirconium tetrachloride. The suspension was warmed to room temperature, stirred for a further 2 hours, filtered and extracted with dichloromethane. The solution was concentrated, and the precipitate was filtered, washed with a small amount of ether and then with hexane, and finally dried to obtain 0.66 g (0.0011 mol) of the complex in 23% yield with respect to the zirconium chloride used.¹H NMR(CDCl₃δ ppm vs TMS): 5.51(s, 4H); 2.59(t, 8H); 1.6(m, 8H); 1.30(m, 24H); 0.63(s, 6H).¹H NMR(CDCl₃δ vs TMS): -5.01; 22.84; 25.12 of; 25.14 of the total weight of the mixture; 25.94 of; 29.50; 114.18, respectively; 141.07.

example synthesis of 51, 2-bis (4, 5, 6, 7,8-pentahydro azulen-2-yl) -tetramethyldisilyl-zirconium dichloride (CP 191C).

A suspension of 5.1 g (0.036 mol) of the lithium salt of 2, 4, 5, 6, 7, 8-pentahydroazulene, prepared as disclosed in Italian patent application IT-A-MI95/002731, was cooled to-70 ℃ and 3.4 g (0.018 mol) of 1, 2-dichlorotetramethyldisilane were added dropwise. The temperature rose to room temperature during the overnight period. The reaction mixture was hydrolyzed and extracted with petroleum ether. In the case of solvent evaporation, obtaining6.5 g of solid product, after trituration in methanol, gave 4.6 g (0.012 mol, 67% yield) of pure 1, 2-bis (2, 4, 5, 6, 7, 8-hexahydroazulen-2-yl) -tetramethyldisilane. The ligand was dissolved in 160ml of diethyl ether and 15ml of a 1.6M solution of LiMe in diethyl ether were added. A solid of rubbery appearance was isolated. 50ml of THF were added and the solid was subsequently dissolved therein, forming a white crystalline precipitate. The mixture was stirred for one hour and then cooled to-70 ℃. Then 3.2 g (0.0137 mol) of ZrCl were added₄The temperature was raised to room temperature. The mixture was filtered and the white solid was washed with diethyl ether followed by hexane. The raffinate was extracted with dichloromethane (3X 50 ml). The volume was reduced to 20ml and the resulting solid was filtered and washed with a small amount of dichloromethane to yield 0.82 g of complex (13% yield).¹H NMR (δ ppm relative to TMS): 6.29(s, 4H); 2.8(dt, 4H); 2.55(dd, 4H); 2.05(m, 2H); 1.90(m, 4H); 1.55(q, 2H); 1.18(q, 4H); 0.40(s, 12H).¹³C NMR (δ ppm relative to TMS): -2.3; 28; 30, of a nitrogen-containing gas; 32, a first step of removing the first layer; 116; 124;138.5.

example synthesis of 61- [4, 5, 6, 7, 8-Pentahydroazulen-2-yl]-2- [ 3-methyl-inden-1-yl]-tetramethyldisilyl-zirconium dichloride (CP 266E).

5.1 g (0.036 mol) of the lithium saltof 2, 4, 5, 6, 7, 8-hexahydroazulene, prepared as in example 5, were dissolved in 200ml THF and maintained at-70 ℃. 9.0 g (0.048 mol) of 1, 2-dichloro-tetramethyldisilane are added dropwise. The temperature was then raised to room temperature, followed by evaporation of the solvent. The residue was dissolved in pentane and then filtered. The pentane was evaporated and the solid was dissolved in 75ml of THF and then added at-70 ℃ to a 1-methyl-indenyllithium solution consisting of a solution of 8.5 g (0.065 mol) of 1-methylindene in 150ml of THF and 25ml of a 2.5M solution of LiBu in hexane. The temperature was then raised to room temperature, and the mixture was hydrolyzed in water and extracted with petroleum ether. After evaporation of the solvent, the residue was purified by elution on a silica gel column using petroleum ether and then petroleum ether containing 5% of dichloromethane, thus obtaining 10.4 g.

3.1 g (0.0082 mol) of the ligand prepared previously were dissolved in 150ml of diethyl ether, and 6.5ml of a 2.5M solution of LiBu in hexane were added. A precipitate is formed by rapid reaction. The mixture was stirred for 8 hours, cooled to-60 ℃ and 2.1 g (0.009 moles) of solid zirconium tetrachloride were added. Then, the temperature was raised to room temperature, and the mixture was stirred for 3 hours. The suspension was then filtered and the filtrate was concentrated to 15 ml. The obtained solid is filtered and first usedA small amount of ether was washed twice with pentane. After drying, 1.3 g of complex (29% yield) were obtained.¹H NMR (δ ppm relative to TMS): 7.74(dd, 1H); 7.62(dd, 1H); 7.26(m, 2H); 6.68(s, 1H); 6.38(d, 1H); 5.78(d, 1H); 2.66(m, 4H); 2.50(s, 3H).1.88(m, 4H); 1.40(m, 2H); 0.59(s, 3H); 0.52(s, 3H); 0.48(s, 3H); polymerization runs 1-16-Synthesis of ethylene/propylene copolymer and ethylene/propylene/diene terpolymer (s, 3H).

In a 3.3 l pressure-resistant reactor, thermostatically adjustable and equipped with a magnetic scraper stirrer, the polymerization is carried out according to the following procedure:

after flushing with propylene containing 5 wt%/v triisobutylaluminum and washing of the reactor with fresh propylene, 2 liters of "polymerization grade" liquid propylene and possibly a third monomer (ENB) were fed at 23 ℃. The reactor was then warmed to the predetermined temperature for polymerization. A10% TIBA (triisobutylaluminum) solution in hexane (equivalent to 1.5 moles of Al) was added. The optional hydrogen and ethylene are then passed in gaseous form through a submerged tube into the reactor at a predetermined ratio to achieve the desired partial pressure.

The catalyst was prepared as follows:

a solution of metallocene in 10ml of anhydrous toluene was prepared in a glass funnel maintained under nitrogen and to this solution was added the necessary amount of Methylaluminoxane (MAO) solution (commercial product WITCO known as Eurocen Al5100/30T) at 30% in toluene to obtain the desired Al/Zr ratio.

The resulting solution was poured into a steel drum kept under nitrogen atmosphere, and rapidly introduced into the reactor by means of an overpressure of nitrogen. The pressure of the reactor was kept constant by feeding ethylene from a controlled weight tank. After one hour, the ethylene feed was discontinued, the residual monomer was degassed and the reactor was cooled to room temperature.

The polymer is discharged, homogenized with a roller mixer and finally characterized.

Table 1 specifies: c₂Ethylene content in the liquid phase (mol%); ENB ═ ENB content in the liquid phase (mol%); t-temperature, H₂The amount of hydrogen (molecular weight regulator) which enters the reactor before polymerization and is expressed in moles/liter; MAO/Zr-cocatalyst moles with ZrA ratio; yield-polymerization yield (kg of obtained polymer/g of Zr fed); c₃Propylene content (wt%) in the resulting polymer; ENB ═ ENB content in the resulting polymer (wt%); intrinsic viscosity of the polymer, dl/g; mooney ═ mooney viscosity ML (1+4, 100 ℃); m_wWeight average molecular weight; m_w/M_nThe ratio of weight average molecular weight to number average molecular weight. Polymerization test 17

Unlike the previous examples, this experiment was carried out by using a catalytic system prepared according to the ion-pair technique.

2ml of toluene, 0.3mg (5.53X 10)^-7Molar) metallocene prepared as described in example 5 CP191C, and 10% Al (iso-Bu) to give an Al/Zr ratio of 300₃The hexane solution was introduced into a 100ml glass test tube into which nitrogen was pumped.

The solution is thermostatically regulated at 20 ℃ for 1 hour with stirring, then diluted with 1ml of toluene, and a 0.2% (C) is added₆H₅)₃C[B(C₆H₅)₄]The B/Zr molar ratio of the toluene solution of (1) was 4.

The solution obtained is then immediately introduced into a pressure-resistant reactor, before which 2 l of propylene and 0.9X 10 l of propylene are introduced^-3Mole Al (i-Bu)₃Has been introduced into the reactor, thermostatically adjusted at 45 ℃ and saturated with ethylene so that the content of ethylene in the liquid phase is 20% by moles.

After 1 hour of polymerization, 270 g of a copolymer having a propylene content of 39% by weight and a Mooney viscosity ML (1+4, 100 ℃) of 23 were discharged.

The polymerization yield was 5400 kg/g Zr-h.

This example shows that the catalyst of the present invention providesa high yield ethylene/propylene copolymer using an activator capable of generating ion pairs by reaction with the metallocene of the general formula (I) as a co-catalyst replacing MAO. Physical-chemical analysis and characterization

The following measurements were carried out on the resulting polymer:

propylene content and ENB content:

the polymer was characterized by IR using a FTIR Perkin-Elmer spectrophotometer model 1760 with 0.2mm thick film.

Intrinsic viscosity:

the assay was carried out at a temperature of 135 ℃ with the polymer dissolved in o-dichlorobenzene. The falling time of the solvent and solution was measured by increasing the concentration of the polymer to be measured using an Ubbelohde viscometer.

By reducing the polymer concentration, the intrinsic viscosity value is obtained by extrapolating the viscosity to zero concentration.

Molecular weight distribution:

the test was carried out in o-dichlorobenzene using a Waters ALC/GPC 135 instrument using gel permeation chromatography at a temperature of 135 ℃. Calibration curves for calculating molecular weight were obtained using monodisperse polystyrene standards using the Mark-Houwink equation for linear polyethylene and polypropylene. Molecular weight correction was performed using the Sholte equation with respect to its composition (J.Appl.Polym.Sci.1984, 29, Pages 3363-.

Mooney viscosity (1+4)

The test was carried out using a Monsanto "1500S" viscometer at a temperature of 100 ℃ according to ASTM D1646/68. Run 18-vulcanization

The preparation of the mixture to be vulcanized uses the following formulation (relative to 100 parts of the amount of EPDMprepared in test 15): 55 parts of carbon black; 5 parts of zinc oxide; 5 parts of peroxide; 1.5 parts of sulfur; 2.25 parts of an accelerator; 30 parts of paraffin oil.

The vulcanization of the mixture is carried out on a plate press at 165 ℃ and 18MPa for 40 minutes.

The mechanical properties were measured on vulcanization test specimens taken from molded plaques.

The ultimate tensile strength obtained was 101Kg/cm²(ASTM D412-68 method), elongation at break 925% (ASTM D412-68), permanent set at 200% 12(ASTM D412-68), shore a 54.

TABLE 1

Method of producing a composite material	Test of	C2％	ENB％	T(℃)	H2	MAO/Zr(mol)	Yield of	C3％	ENB％	ηdl/g	Mooney viscosity	Mw1/1000	Mw/Mn
														CP172	1	20	_	40	_	4200	3600	38	_	_	_	3	2.7
CP172	2	20	0.4	40	_	3800	2550	38	3.7	_	_	5	2.4
														CP138	3	20	_	40	_	3000	1740	54	_	_	_	2.5	2.5
CP266E	4	20	_	45	_	5000	1800	32	_	_	＞120	_	_
														CP266E	5	10	_	45	_	4200	1300	49	_	_	100	244	2.5
CP266E	6	12	_	45	0.45	2500	900	49	_	_	68	198	2.4
														CP266E	7	14	0.5	45	0.45	2600	610	43	0.5	_	53	_	_
CP266E	8	14	1	45	0.45	2000	500	43	1.5	_	56	_	_
														CP136A	9	3	_	40	_	1170	100	37	_	0.45	_	_	_
CP136A	10	4.5	_	40	_	940	250	23	_	0.7	_	46	2.2
														CP136A	11	8	_	40	_	2300	240	17	_	0.8	_	_	_
CP191C	12	16	_	40	0.45	4040	2000	48	_	1.7	66	197	2.3
														CP191C	13	20	_	45	0.45	4900	4600	54	_	1.6	76	_	_
CP191C	14	18	0.4	40	0.45	4800	2570	45	1.3	1.9	90	_	_
														CP191C	15	18	1	40	0.45	4800	2580	55	2.1	1.8	79	251	2.6
CP192	16	15	_	40	_	5050	300	38	_	0.47	_	26.5	1.9

Using the metallocenes CP172 (runs 1 and 2), CP138E (run 3), CP136A (runs 9-11) and CP192 (run 16), low molecular weight copolymers suitable for use in preparing lubricating oil additives can be obtained; in particular the metallocene CP192, a particularly narrow molecular weight distribution copolymer was obtained (run 16), whereas the metallocene CP172 was characterized by a high catalytic activity. Experiment 2 shows that low molecular weight ENB-containing terpolymers can be obtained using the same metallocene CP 172.

Using the metallocenes CP191C and CP266E, high molecular weight copolymers and terpolymers can be obtained, particularly suitable for the preparation of vulcanized elastomers, which can also be reflected in the mechanical property data obtained after vulcanization of the polymer from test 15.

Claims (12)

1. In the presence of an optional diene, ethylene and C₃-C₂₀α -catalytic component for the copolymerization of olefins, having general formula (I):wherein: a is a cyclopentadienyl derivative having the general formula (II)Wherein R is₁And R₂Selected from H and C₁-C₃An alkyl group; n is a positive integer from 2 to 18; b is selected from: 1) any cyclopentadienyl derivative a defined above; 2) a monofunctional cyclopentadienyl group (F) selected from the group consisting of cyclopentadienyl, indenyl, fluorenyl, and corresponding alkyl, aryl, trialkylsilyl substituted derivatives; the bridge Q between A and B is a bifunctional group selected from: a) c₁-C₂₀Linear, branched, cyclic alkylene; b) an alkyl-substituted silylene or disilylene group; c) an alkyl-substituted silalkylene group; m is selected from the group consisting of titanium, zirconium,hafnium, vanadium, niobium; x is chlorine; except for compounds in which a ═ B and n ═ 4.

2. A catalytic component according to claim 1 characterised in that M is zirconium.

3. A catalytic component according to claim 1 characterised in that n is selected from 3, 5, 6 and 10.

4. A catalytic component according to claim 1 wherein Q is selected from the group consisting of branched alkylene derivatives, dialkylsilylene and tetraalkyl-substituted disilylene groups.

5. A catalytic component according to claim 4 characterised in that Q is selected from isopropylidene, dimethylsilylene and tetramethyldisilylene.

6. A catalytic component according to claim 1 characterised in that when group B is different from group A, group B is selected from the group consisting of cyclopentadienyl, indenyl and fluorenyl.

7. A catalytic component according to claim 1 wherein R₂H and two R₁Is H.

8. A process for the preparation of a catalytic component of formula (I) comprising reacting a compound of formula HA-Q-BH, wherein Q, A and B are as defined above, with an alkyl metal to obtain the corresponding dianion, followed by reaction with MX₄Reacting to obtain the compound of the general formula (I).

9. A process for the preparation of a compound of formula (I) according to claim 8, wherein M ═ Zr, characterized in that the metal alkyl is lithium alkyl and compound MX is₄Is zirconium tetrachloride.

10. C₂-C₂₀α -Process for the homo-and copolymerization of olefins, optionally in the presence of diolefins, using a catalytic system comprising a compound of formula (I).

11. A slurry process for preparing an ethylene/α -olefin copolymer or an ethylene/α -olefin/diene terpolymer comprising the steps of:

1) feeding an α -olefin, optionally diluted with a hydrocarbon, and possibly a diolefin, to a polymerization reactor at a pressure such that the α -olefin is in the liquid state;

2) adding a sufficient amount of ethylene to the mixture obtained in step (1) to maintain the desired ethylene/α -olefin ratio in the liquid phase;

3) optionally in the presence of an alkylate (VII), with a catalyst system comprising one or more metallocenes and one or more cocatalysts selected from the group consisting of aluminoxanes and compounds of formula (III) (Ra)_xNH_4-xB(Rd)₄Or (IV) (Ra)₃PHB(Rd)₄Or (V)B (Rd)₃Or (VI) CPh₃[B(Rd)₄]A compound of (1);

4) the mixture obtained in step (3) being reacted for a time sufficient to polymerize an ethylene/α -olefin system with possible diolefins, characterized in that the catalytic system comprises a metallocene chosen from the group consisting of the metallocenes of general formula (I):wherein: a, B, Q, M, X have the meanings given in claim 1.

12. The process of claim 11, wherein ethylene-propylene (EPM) or ethylene-propylene-diene (EPDM) copolymers are prepared having a propylene content of from 10 to 70 wt.%.