DE19960123A1 - Process for the homogeneous catalytic production of highly branched amorphous polyolefins - Google Patents

Abstract

The invention relates to a method for the homogeneous catalytic production, starting from ethene, of highly branched amorphous polyolefins which have an elastomeric characteristic profile. In a first step of said method a) ethene is oligomerized in the presence of a transition metal compound of general formula (I), whereby R<1> and R<2> represent C4 to C16 heteroaryl or C6 to C16 aryl with hydrogen substituents in both vicinal or ortho positions in relation to the binding site between the aryl or heteroaryl and N<a> or N<b> and is optionally oligomerized in the presence of a co-catalyst in an inert solvent. In a further step b), a transition metal compound of general formula (II) is added to the oligomerization mixture produced according to step a) and the reaction is continued in the presence of ethene. In a subsequent step c), the polymer product obtained is isolated.

Description

The present invention relates to a method for homogeneous kata lytic production of highly branched amorphous polyolefins with an elastomeric property profile based on ethene.

The person skilled in the art is aware of highly branched polyolefins, provided that they are sufficiently amorphous as an elastomeric component polymer Mixtures and single polymers for the purpose of toughening quantities (see also plastics, 1999, 89, 154-162). Highly ramified Polyolefins generally consist of a polyethylene backbone with statistically distributed data of different lengths Alkyl side branches. Unlike z. B. have polybutadiene rubbers highly branched polyolefins are usually not double bonded and are therefore not very sensitive or not at all against weather influences.

Different approaches have been developed for the production of branched polyolefins. For a font in the U.S. Patent 5,272,236 described provision, 1-alkenes [(η ⁵ -C ₅ Me ₄₎ SiMe ₂ (η ¹ -NCMe _3)] blank as 1-hexene or 1-octene in the presence of TiCl ₂ as Copolymerize the catalyst with ethene to form branched polyethylene. This variant always requires the upstream, separate production of 1-olefins. Beach and Kissin, Polym. Sci., 1984, 22, 3027, combine two Ziegler-Natta catalysts to prepare branched polyolefins based on ethene. By means of a catalyst mixture of titanium alkoxides and triethylaluminum, 1-butene is primarily produced, which is copolymerized with ethene in the presence of titanium tetrachloride supported on magnesium chloride and triethylaluminium. The branching rate, however, is too low with 20 alkyl branches per 1000 carbon atoms to provide sufficient amorphous material. In addition, the low yields of an application of this method are not only opposed to the technical scale.

According to a regulation by Barnhart and Bazan, J. Am. Chem. Soc., 1998, 120, 1082-1083, one also arrives from ethene to branched polyolefins when two metallocene complexes coexist be combined. However, this only works if the polymerization activity of the transition metal ver used ties to ethene is very well coordinated because  otherwise either no polyolefin backbone or none at all polymerizing 2-alkenes are formed. Furthermore is after Barnhart and Bazan make sure that the used over gear metal compounds no dimeric coupling products from the prepared 1-alkenes deliver, resulting in inhomogeneous product would lead to mixing. In addition, the two are allowed in their reak activity of different metallocene compounds with each other do not interact chemically. This diverse project gave for the production of branched polyolefins from ethene according to Barnhart and Bazan, it is only a well-defined zirconocene complex fair, which is complexed with two boratobenzene rings, the free valence on the boron atom each having an ethoxy group has to be saturated. Already exchanging the ethoxy for a phenyl group no longer leads to the desired branched Polyolefins.

Brookhart et al., J. Am. Chem. Soc. 1995, 117, 6414-6425 genes based on ethene using a nickel diinkinkata lysators also to branched polyethylene. In the alkylver branches are mostly methyl groups, which is why the elastomeric property profile of the poly olefine is not very pronounced. Admittedly, will comply with the palladium complexes are highly branched from ethene amorphous polyolefins obtained, however, are Productivities so low that a technical application is out of the question.

The combined use of olefin polymerization catalysts leads at Ahn et al., Polymer Engineering an Science, 1999, 39, 1257-1264, on polyethylene with bimodal particle sizes distribution or to polyethylene with very broad molecular weight distribution. The authors initially have ethene with one Metallocene compound, e.g. B. with bis (cyclopentadienyl) zirconium dichloride or bis (indenyl) zirconium dichloride, implemented, wherein the reactivity of the catalyst used by adding Triethylaluminum had to be reduced, and then the reaction after adding a Ziegler / Natta compound, e.g. B. Titanium tetra chloride-vanadium oxide trichloride, continued.

The synthesis of polyolefin blends starting from ethene Use of a catalyst composition consisting of a poly merization catalyst based on an early transition metal compound and from a polymerization catalyst the basis of a late transition metal compound exists described in DE-A 197 07 236. As an early transition Ziegler / Natta catalysts, e.g. B. on based on titanium tetrachloride or metallocene catalysts  the base of titanium, zirconium or hafnium cyclopentadienylkom plex, as late transition metal compounds z. B. Diimine complexes of nickel or palladium. In the preserved Polymer blends are linear or only slightly branched poly ethylene in addition to branched polyethylene.

Fink et al., Macromol. Chem. Rapid Commun., 1991, 12, 697-701, have nickel-ylide complexes with bridged and unbridged Metallocene complexes combined to branch out from ethene to produce polyethylene. The proportion of incorporated α-olefin however, is regularly very low. In addition, only through coarse amounts of methylalumoxane as a cocatalyst acceptable acti vities, with an increased tendency to dimerization in To buy.

EP-A 0 250 999 describes the combined use of a nickel Ylid complexes as an oligomerization catalyst with one on sili cagel supported heterogeneous chromium polymerization catalyst for the production of branched polyolefins based on ethene knows. In this way, however, only polyolefins with very long alkyl branches, which is why materials with part crystalline or crystalline, but not with amorphous properties profile can be obtained.

WO 99/10391 describes simultaneous and sequential Use of different polymerization catalysts described. However, even with steric sophisticated nickel diimine complexes and bis (cyclopentadienyl) zir Konocendichloridkomplexen only partially crystalline materials ten.

According to WO 99/50318 for the production of branched polyolefins from, for example, ethylenetridentate iron bisimine complex compounds and metallocene catalysts are either added simultaneously or sequentially to the reaction mixture. According to the described method, however, branched polyolefins with sufficiently high alkyl branching rates and suitable alkyl branching patterns, which also have a sufficiently elastomeric property profile, cannot be reproducibly achieved in order to be used as toughness modifiers. This is already contradicted by the thermal properties of the polymers described, which have melting points T _m ≧ 100 ° C. In addition, the α-olefins formed cannot be reliably incorporated into the copolymer chain by the process described, which is why these compounds remain as residues in the copolymer and contaminate it and, if appropriate, have to be removed in a complex manner by additional purification steps.

It would be desirable for the production of highly branched poly olefins based on ethene on two or more components To be able to fall back on catalyst systems that are easy Let it handle, show high activities and too much branching rates and thus lead to amorphous elastomeric products. The present invention was therefore based on the object To make procedures available with the preparative simple and efficient way amorphous or largely amorphous elasto mere polyolefins also on an industrial scale in satisfactory the orphan can be preserved.

Accordingly, a process for the homogeneous catalytic production of highly branched polyolefins with an elastomeric property profile has been found, in which in a first step

• a) ethene in the presence of at least one transition metal compound of the general formula (I)
  in which the substituents and indices have the following meaning:
  R ¹ , R ² C ₄ to C ₁₆ heteroaryl or C ₆ to C ₁₆ aryl with hydrogen substituents in the two vicinal positions to the point of connection between aryl or heteroaryl and N ^a or N ^b ,
  R ³ , R ^{4 are} hydrogen, C ₁ - to C ₁₀ -alkyl, C ₃ - to C ₁₀ -cycloalkyl, C ₆ - to C ₁₆ -aryl, alkylaryl with 1 to 10 C atoms in the alkyl and 6 to 14 C atoms in the aryl part or Si (R ⁸ ) ₃ with
  R ^{8 is} C ₁ to C ₁₀ alkyl, C ₃ to C ₁₀ cycloalkyl, C ₆ to C ₁₆ aryl, alkylaryl with 1 to 10 C atoms in the alkyl and 6 to 14 C atoms in the aryl part,
  R ⁵ , R ⁶ , R ^{7 are} hydrogen, C ₁ - to C ₁₀ -alkyl, C ₃ - to C ₁₀ -cyclo alkyl, C ₆ - to C ₁₆ -aryl, alkylaryl with 1 to 10 C atoms in the alkyl and 6 to 14 carbon atoms in the aryl part or Si (R ⁸ ) ₃ or functional groups based on the elements of groups IVA to VIIA of the Periodic Table of the Elements or R ⁵ and R ⁶ and / or R ⁶ and R ⁷ together form one fused five-, six- or seven-membered aliphatic or aromatic, substituted or unsubstituted carbo- or heterocycle,
  M ^I Fe, Ru, Co, Rh, Ni or Pd
  T, Q neutral or monoanionic monodentate ligands or T and Q together form a diketoenolate unit or a C ₂ or C ₃ alkylene unit with a methyl ketone or a linear C ₁ to C ₄ alkyl ester or nitrile end group,
  A a non or poorly coordinating anion,
  m, p 0, 1, 2 or 3,
  q 1, 2 or 3 and n 1, 2 or 3
  and optionally one or more cocatalysts in the form of strong neutral Lewis acids, ionic compounds with a Lewis acid cation or ionic compounds with a Bronsted acid as a cation oligomerized in an inert solvent, in a further step
• b) at least one transition metal compound of the general formula (II)
  in which the substituents and indices have the following meaning:
  R ⁹ to R ^{12 are} hydrogen, C ₁ to C ₁₀ alkyl, C ₃ to C ₁₀ cycloalkyl, C ₆ to C ₁₆ aryl, alkylaryl having 1 to 10 C atoms in the alkyl and 6 to 14 C atoms in the aryl part or Si (R ⁸ ) ₃ or functional groups based on the elements of groups IVA to VIIA of the periodic table of the elements or R ⁹ and R ¹⁰ and / or R ¹¹ and R ¹² each together form an elliptical five-, six- or seven-membered aliphatic or aromatic, substituted or unsubstituted carbo- or heterocycle,
  M ^{II is} a metal from group IIIB, IVB, VB or VIB of the Periodic Table of the Elements,
  T ', Q' is a hydrogen atom, a C ₁ to C ₁₀ alkyl or C _{6 to} C ₂₀ aryl radical, a halogen atom, -OR ', -SR', -OSiR ' ₃ , -SiR' ₃ , -CR " ₂ SiR ' ₃ , -PR' ₂ , -NR ' ₂ , toluene sulfonyl, trifluoroacetyl, trifluoromethanesulfonyl, nonafluorobutanesulfonyl, 2,2,2-trifluoroethane sulfonyl,
  Z -CR ' ₂ -, -SiR' ₂ -, -GeR ' ₂ -, -SnR' ₂ -, -BR'- or -O- with
  R 'C ₁ to C ₂₀ alkyl, C ₃ to C ₁₀ cycloalkyl, C ₆ to C ₁₆ aryl, alkylaryl having 1 to 10 C atoms in the alkyl and 6 to 10 C atoms in the aryl part, C ₁ to C ₂₀ alkoxy, C ₃ to C ₁₀ cycloalkoxy, C ₆ to C ₁₆ aryloxy or alkylaryloxy having 1 to 10 C atoms in the alkyl and 6 to 10 C atoms in the aryl part,
  k 1, 2 or 3,
  G -O-, -S-, -NR ", -PR", -BR "-, -OR" -, -SR "-, -NR '' ₂ , -PR" ₂ or a radical of the formula (III)
  in which the substituents R ⁹ to R ^{12 have} the abovementioned meaning, R "is hydrogen, C ₁ - to C ₂₀ -alkyl, C ₃ - to C ₁₀ -cycloalkyl, C ₆ - to C ₁₅ -aryl, alkylaryl with 1 to 10 carbon atoms in the alkyl and 6 to 10 carbon atoms in the aryl part or C ₃ - to C ₃₀ organosilyl, or
  Z _k and G together form a substituted or unsubstituted aromatic or heteroaromatic structure of 4 to 16 ring carbon atoms or
  Z _k and R ⁹ and / or R ¹² together form a mono- or polycyclic aliphatic, aromatic or heteroaromatic ring system,
  and optionally further cocatalysts as described under step a) are added to the oligomerization mixture according to a) and the reaction is continued in the presence of ethene and then the polymer product obtained is isolated in step c).

The radicals R ¹ and R ² in the compound (I) represent C ₄ - to C ₁₆ -heteroaryl or C ₆ - to C ₁₆ -aryl groups, each in their two vicinal (ortho) positions to the point of attachment between Imine nitrogen atom N ^a or N ^b and the aryl or heteroaryl radical, ie, for example in the case of a phenyl radical, are ortho-permanently substituted for the covalent bond between the phenyl radical and the imine nitrogen with hydrogen atoms.

The substituents R ¹ or R ² in a compound (I) can match or differ from one another in terms of their aromatic or heteroaromatic ring system and / or further substituents which are not in the vicinal position.

The heteroaryl or aryl radicals R ¹ and R ² can have one or more substituents in addition to the vicinal or ortho hydrogen atoms described in the description. Examples of such substituents are functional groups based on the elements from groups IVA, VA, VIA or VIIA of the Periodic Table of the Elements. Suitable are, for example, straight or branched C ₁ to C ₁₀ alkyl, preferably C ₁ to C ₆ alkyl, such as methyl, ethyl, n- or i-propyl, n-, i- or t-butyl, partially or perhalogenated C ₁ to C ₁₀ alkyl, preferably C ₁ to C ₆ alkyl such as trifluoro or trichloromethyl or 2,2,2-trifluoroethyl, triorganosilyl such as trimethyl, triethyl, tri-t-butyl, triphenyl or t -Butyldiphenylsilyl, the nitro, cyano or sulfonato group, amino, for example NH ₂ , dimethylamino, di-i-propylamino, di-n-butylamino, diphenylamino or dibenzylamino, C ₁ - to C ₁₀ -alkoxy, preferably C ₁ - to C ₆ alkoxy such as methoxy, ethoxy, i-propoxy or t-butoxy, or halogen such as fluoride, chloride, bromide or iodide.

Preferred among the aryl radicals R ¹ , R ² are the phenyl, naphthyl and anthracenyl groups. Phenyl and naphthyl groups are particularly preferred and the phenyl group is particularly preferred, these aryl radicals also each having the aforementioned further substituents in the positions which are not vicinal or. are ortho-permanent, can wear.

Among the aforementioned phenyl radicals, those are particularly suitable which, in the para position to the attachment position to the imine nitrogen, contain a hydrogen atom or a methyl, i-propyl, t-butyl, trichloromethyl, trifluoromethyl, methoxy, ethoxy, chlorine - Or have bromine residue. Particularly preferred radicals R ¹ , R ² are, for example, 4-i-propylphenyl, 4-methylphenyl, 4-methoxyphenyl or phenyl.

The C ₄ to C ₁₆ heteroaryl radicals R ¹ and R ² in the sense of the present invention are to be understood as meaning substituted or unsubstituted heteroaryl radicals insofar as they have hydrogen atoms in their two vicinal positions at the point of attachment to the imine nitrogen. Preferred are C ₄ - to C ₉ heteroaryl radicals such as the pyrrolidyl (linked to the imine nitrogen via a ring carbon atom) or the pyrrolid group (linked to the imine nitrogen via the pyrrole nitrogen) or the imidazolyl (CN linked), imidazolid (NN -linked), benzimidazolyl, benzimidazolid, pyrazolyl, pyrazolid, pyridinyl, pyrimidinyl, quinolyl or the isoquinolyl group. Among these, the pyrrolidyl and especially the pyrroli drest should be emphasized.

The radicals R ³ and R ⁴ in (I) are hydrogen, C ₁ - to C ₁₀ -alkyl, C ₃ - to C ₁₀ -cycloalkyl, C ₆ - to C ₁₆ -aryl, alkylaryl with 1 to 10 C-atoms in Alkyl and 6 to 14 carbon atoms in the aryl part, silyl (Si (R ⁸ ) ₃ ), amino (N (R ⁸ ) ₂ ), ether (OR ⁸ ) or a thioether (SR ⁸ ) in question. Among the radicals R ³ and R ⁴ are hydrogen, methyl, ethyl, i-propyl, t-butyl, methoxy, ethoxy, i-propoxy, t-butoxy, trifluoromethyl, phenyl, naphthyl, tolyl, 2-i-propylphenyl, 2 -t-Butylphenyl, 2,6-di-i-propylphenyl, 2-trifluoromethylphenyl, 4-methoxyphenyl, pyridyl or benzyl and in particular hydrogen, methyl, ethyl, i-propyl or t-butyl are preferred. Ligand compounds with these residues can be found in K. Vrieze and G. von Koten, Adv. Organomet. Chem., 1982, 21, 151-239, and J. Matei, T. Lixandru, Bul. Inst. Politeh. Isai, 1967, 13, 245. In addition, ³ , R ^4, 1,4-dithiane, as described in WO 98/37110, are preferred as heterocyclic systems.

The radicals R ⁵ , R ⁶ and R ^{7 are,} independently of one another, what hydrogen, C ₁ - to C ₁₀ -alkyl, C ₃ - to C ₁₀ -cycloalkyl, C ₆ - to C ₁₆ -aryl, alkylaryl with 1 to 10 C- Atoms in the alkyl and 6 to 14 carbon atoms an aryl part or a silyl radical (Si (R ⁸ ) ₃ ) or a functional group based on the elements of groups VA to VIIA of the periodic table of the elements. Suitable functional groups are, for example, amino, such as NH ₂ , dimethylamino, di-i-propylamino, di-n-butylamino, diphenylamino or dibenzylamino, C ₁ - to C ₁₀ -alkoxy, preferably C ₁ - to C ₆ -alkoxy, for Example methoxy, ethoxy, n- or i-propoxy, n-, i- or t-butoxy, or halogen such as fluoride, chloride, bromide or iodide.

R ⁵ and R ⁶ or / and R ⁶ and R ⁷ can also, together with the pyridyl system, form a fused five-, six- or seven-membered aliphatic or aromatic, substituted or unsubstituted carbo- or heterocycle, for example a substituted one or unsubstituted isoquinoline system.

The radicals R ⁵ , R ⁶ and R ⁷ are preferably hydrogen or methyl, in particular hydrogen.

The radicals R ⁸ are C ₁ to C ₁₀ alkyl, preferably C ₁ to C ₆ alkyl, C ₆ to C ₁₆ aryl, preferably C ₆ to C ₁₀ aryl, or alkylaryl having 1 to 10, preferably 1 to 6 carbon atoms in the alkyl and 6 to 14, preferably 6 to 10 carbon atoms in question. Suitable residues are e.g. B. triorganosilyl such as trimethyl, triethyl, triphenyl or t-butyl-diphenylsilyl.

Unless expressly described otherwise elsewhere, the alkyl, cycloalkyl, aryl and alkyl aryl groups of the radicals ³ to R ⁸ include the following substituents:
C ₁ to C ₁₀ alkyl radicals preferably include, for example, the methyl, ethyl, n- or i-propyl, n-, i- or t-butyl group and the pentyl, hexyl or heptyl group in straight-chain and branched Shape. C ₁ - to C ₁₀ -alkyl radicals also include those which are substituted by functional groups based on the elements of groups IVA, VA, VIA or VIIA of the periodic table, for example partially or perhalogenated alkyl radicals such as trichloromethyl, trifluoromethyl, 2 , 2,2-trifluoroethyl, pentafluoroethyl or pentachloroethyl such as one or more alkyl radicals bearing epoxy groups, for example propenoxy. Among the C ₁ to C ₁₀ alkyl radicals, the C ₁ to C ₆ alkyl radicals are regularly preferred.

Suitable C ₃ to C ₁₀ cycloalkyl radicals include carbocycles and heterocycles, for example substituted and unsubstituted cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclooctyl, pyrrolyl, pyrrolidonyl or piperidinyl. Examples of substituted cycloaliphatic radicals are 1-methylcyclohexyl, 4-t-butylcyclohexyl and 2,3-dimethylcyclopropyl.

Suitable C ₆ to C ₁₆ aryl groups generally include substituted and unsubstituted aryl groups. Among the unsubstituted aryl radicals, the C ₆ to C ₁₀ aryl groups such as phenyl and naphthyl are preferred. Phenyl is particularly preferred. For the unsubstituted as well as the substituted C ₆ - to C ₁₆ aryl groups, the indication of the carbon atoms (e.g. C ₆ -, C ₁₀ - or C ₁₆ -) indicates the number of carbon atoms that the aromatic Form system (with). Carbon atoms from possible alkyl and / or aryl substituents are not yet covered by this information. The statement C ₆ - to C ₁₆ aryl thus also includes, for example, substituted C ₆ to C ₁₆ aryl radicals such as substituted anthracenyl. C ₆ to C ₁₆ aryl radicals accordingly also include those radicals which are single, multiple or persubstituted with functional groups based on the elements from groups IVA, VA, VIA and VIIA of the Periodic Table of the Elements. Suitable functional groups are C ₁ to C ₁₀ alkyl, preferably C ₁ to C ₆ alkyl, C ₆ to C ₁₆ aryl, preferably C ₆ to C ₁₀ aryl, triorganosilyl such as trimethyl, triethyl, Triphenyl- or t-butyl-diphenylsilyl and amino, for example NH ₂ , dimethylamino, di-i-propylamino, di-n-butylamino, diphenylamino or dibenzylamino, C ₁ - to C ₁₀ -alkoxy, before C ₁ - to C ₆ -alkoxy, for example methoxy, ethoxy, n- or i-propoxy, n-, i- or t-butoxy, or halogen such as fluoride, chloride, bromide or iodide.

With regard to the substituents R ³ to R ⁸ , C ₆ to C ₁₆ aryl radicals are also to be understood as meaning substituted and unsubstituted heteroaryl radicals, for example C ₄ to C ₁₃ heteroaryl, preferably C ₄ to C ₉ heteroaryl, such as pyridyl, pyrimidyl , Quinolyl or isoquinolyl.

Suitable alkylaryl radicals R ³ to R ⁸ generally include those having 1 to 10, preferably 1 to 6, carbon atoms in the alkyl and 6 to 14, preferably 6 to 10, carbon atoms in the aryl part, in particular the benzyl group.

The metals M ^I in (I) are the elements iron, cobalt, ruthenium, rhodium, palladium or nickel. In the transition metal compounds (I), iron, cobalt, ruthenium, palladium and nickel are generally formally charged twice or three times positively, rhodium generally formally once or three times positively. Cobalt and iron are preferred among the metals M ^I , and iron is particularly preferred.

In one embodiment, T and Q represent neutral and / or monoanionic monodentate ligands. As a neutral ligand Lewis bases are possible, for example acetonitrile, Benzonitrile, diethyl ether, tetrahydrofuran, amines, ketones, Phosphines, ethyl acetate, dimethyl sulfoxide, dimethyl formamide or hexamethylphosphoric triamide. As a Lewis base sher neutral ligand is also ethene or generally one suitable olefinically unsaturated compound. Monoanionic For example, ligands are carbon ions based on sub substituted or unsubstituted alkyl, aryl or acyl residues or halide ions.

T in (I) preferably denotes a monoanionic radical such as sulfonate, borate, chloride, bromide or iodide, methyl, phenyl, benzyl or a C ₁ - to C ₁₀ -alkyl which has no hydrogen atoms in the β-position to the metal center M ^I . This also includes those radicals which have a C ₁ -C ₄ -alkyl ester or a nitrile end group. Chloride and bromide as halides or trifluoromethyl sulfonate as sulfonate and methyl as alkyl radical are particularly preferred.

The rest Q, like T, preferably represents trifluoromethyl sulfonate, chloride, bromide, iodide, methyl, phenyl, benzyl or a C ₁ - to C ₁₀ -alkyl which has no hydrogen atoms in the β-position to the metal center M ^I and a C ₁ - to C ₄ alkyl ester or a nitrile end group. Furthermore, Q preferably represents acetonitrile, benzonitrile, ethene, triphenylphosphine as monodentate phosphorus compound, pyridine as monodentate aromatic nitrogen compound, acetate, propionate or butyrate, in particular acetate as a suitable carboxylate, a linear alkyl ether, e.g. B. a linear di-C ₂ - to C ₆ -alkyl ether such as diethyl ether or di-i-propyl ether, preferably diethyl ether, a cyclic alkyl ether such as tetrahydrofuran or dioxane, preferably tetrahydrofuran, a linear C ₁ - to C ₄ -alkyl ester, e.g. . B. ethyl acetate, dimethyl sulfoxide, dimethylformamide, hexamethyl phosphoric acid triamide or a halide. In the case of iron complexes (I) (M ^I = Fe) Q is preferably a halide genid, for. B. a chloride or bromide, in the case of cobalt complex (M ^I = Co), Q is preferably chloride.

Furthermore, the radicals T and Q together can be a C ₂ - or C ₃ -alkylene unit with a methyl ketone, a linear C ₁ - to C ₄ -alkyl ester or a nitrile end group or a dike toenolate, for. B. acetylacetonate. T and Q here preferably represent a - (CH ₂ CH ₂ CH ₂ C (O) OCH ₃ unit and in this way form a six-membered cycle together with M ^I. While the terminal methylene unit with M ^{I is} a metal / carbon bond forms, the carbonyl group interacts coordinatively with M ^I.

A non-coordinating or poorly coordinating anion A is to be understood according to the invention to mean those anions whose charge density at the anionic center is reduced due to eletronegative residues and / or whose residues sterically shield the anionic center. Suitable anions A include antimonates, sulfates, sulfonates, borates, phosphates or perchlorates, e.g. B. B [C ₆ H ₃ (CF ₃ ) ₂ ] ₄ - (Tetrakis (3,5-bis- (trifluoromethyl) phenyl) borate), B [C ₆ F ₅ ] ₄ -, BF ₄ -, SbF ₆ -, AlF ₄ -, AsF ₆ -, PF ₆ - or trifluoroacetate (CF ₃ SO ₃ -). B [C ₆ H ₃ (CF ₃ ) ₂ ] ₄ - are preferred. SbF ₆ - and PF ₆ -. Borates, in particular B [C ₆ H ₃ (CF ₃ ) ₂ ] ₄ -, are particularly preferably used. Suitable non-coordinating or poorly coordinating anions A and their preparation are, for. B. at SH Strauss, Chem. Rev. 1993, 93, pp. 927-942, and in W. Beck and K. Sünkel, Chem. Rev. 1988, 88, pp. 1405-1421.

Preferred transition metal compounds (I) are, for example:
2,6-bis [1- (phenylimino) ethyl] pyridine-iron (II) chloride,
2,6-bis [1- (4-methylphenylimino) ethyl] pyridine-iron (II) chloride,
2,6-bis [1- (4-isopropylphenylimino) ethyl] pyridine-iron (II) chloride
2,6-bis [1- (4-methoxyphenylimino) ethyl] pyridine-iron (II) chloride,
2,6-bis [1- (4-trifluoromethylphenylimino) ethyl] pyridine-iron (II) chloride and the corresponding iron (II) bromide and cobalt (II) chloride complexes.

The transition metal compounds (I) have a tridentate bisiminchelate ligand as the structural element (in formula (I) the structural element that is obtained with the components M ^I , T, Q and A omitted). These tridentate ligands can e.g. B. from 2,6-diacetylpyridine by reaction with primary amines such as aniline, 4-methylphenylamine, 4-methoxyphenylamine, 4-trifluoromethylphenyl or 4-t-butylphenylamine (see also J. Org. Chem. 1967, 32, 3246) .

For a process for the production of transition metal compounds (I) is hereby expressly referred to Brookhart et al., Macro molecules, 1999, 32, 2120-2130.

In process step a) one or more transition metal Compounds (I) side by side for olefin oligomerization be used.

The transition metal compound (I) can be added in process step a) as a cocatalyst, a strong neutral Lewis acid, an ionic compound with Lewis acidic cations or an ionic compound with a Brönstadt acid as a cation. Suitable ionic compounds with Lewis acid cations fall, for. B. under the general formula

L ^{l +} (YX ¹ X ² X ³ X ⁴ ) _l⁻ (IVa),

in the
L is an element of main group I or II of the periodic table of the elements, such as lithium, sodium, potassium, rubi dium, cesium, magnesium, calcium, strontium or barium, in particular lithium or sodium, or a silver, carbonium , Oxonium, per or partially alkyl and / or aryl substituted ammonium, sulfonium or 1,1'-dimethylferrocenyl cation,
Y an element of III. Main group of the periodic table of the elements means, in particular boron, aluminum or galium, preferably boron,
X ¹ to X ⁴ independently of one another are hydrogen, linear or branched C ₁ to C ₁₀ alkyl, preferably C ₁ to C ₈ alkyl, such as methyl, ethyl, n-propyl, 1-propyl, n-butyl, i-butyl, t-butyl or n-hexyl, mono- or poly-substituted C ₁ - to C ₁₀ -alkyl, preferably C ₁ - to C ₈ -alkyl, z. B. with halogen atoms such as fluorine, chlorine, bromine or iodine, C ₆ - to C ₁₆ -aryl, preferably C ₆ - to C ₁₀ -aryl, e.g. B. phenyl, which can also be substituted one or more times, for example with halogen atoms such as fluorine, chlorine, bromine or iodine, for. B. pentafluorophenyl, alkylaryl having 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms in the alkyl radical and 6 to 14 carbon atoms, preferably 6 to 10 carbon atoms in the aryl radical, for. B. benzyl, fluorine, chlorine, bromine, iodine, C ₁ - to C ₁₀ alkoxy, preferably C ₁ - to C ₈ alkoxy, such as methoxy, ethoxy or i-propoxy, or C ₆ - to C ₁₆ aryloxy, preferably C ₆ to C ₁₀ aryloxy, e.g. B. phenoxy, and
l means 1 or 2.

The anion (YX ¹ X ² X ³ X ⁴ ) ⁻ in a compound of the general formula (IVa) is preferably a non-coordinating counterion. B. boron compounds as they are mentioned in WO 91/09882, to which reference is expressly made here. Particularly suitable cations L go back to the sodium or triphenylmethyl cation and to tetraalkylammonium cations, such as tetramethyl, tetraethyl or tetra-n-butylammonium, dimethylanilinium, or tetraalkylphosphonium cations, such as tetramethyl, tetraethyl or tetra-n-butylphosphonium. Preferred compounds (IVa) are, for example, sodium tetra kis (pentafluorophenyl) borate or sodium tetrakis [bis (trifluoromethyl) phenyl] borate.

As strong neutral Lewis acids such. B. Compounds of the general formula

YX ⁵ X ⁶ X ⁷ (IVb),

in question in the
Y an element of III. Main group of the periodic table of the elements means, in particular boron, aluminum or gallium, preferably boron,
X ⁵ to X ⁷ independently of one another are hydrogen, linear or branched C ₁ to C ₁₀ alkyl, preferably C ₁ to C ₈ alkyl, such as methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t-butyl or n-hexyl, mono- or poly-substituted C ₁ - to C ₁₀ -alkyl, preferably C ₁ - to C ₈ -alkyl, z. B. with halogen atoms such as fluorine, chlorine, bromine or iodine, C ₆ - to C ₁₆ -aryl, preferably C ₆ - to C ₁₀ -aryl, e.g. B. phenyl, which can also be substituted one or more times, for example with halogen atoms such as fluorine, chlorine, bromine or iodine, for. B. pentafluorophenyl, alkylaryl having 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms in the alkyl radical and 6 to 14 carbon atoms, preferably 6 to 10 carbon atoms in the aryl radical, for. B. benzyl or fluorine, chlorine, bromine or iodine.

Particularly preferred among the radicals X ⁵ to X ⁷ are those which have halogen substituents. Pentafluorophenyl should preferably be mentioned. Particularly preferred are compounds of the general formula (IVb) in which X ⁵ , X ⁶ and X ^{7 are} identical, preferably tris (pentafluorophenyl) borane. Furthermore, Alu miniumalkyl- or aluminum haloalkyl compounds, for. B. tri ethyl, tri (n-hexyl) aluminum or di-i-propyl aluminum chloride, particularly suitable cocatalysts (IVb). In addition, lithium and / or magnesium alkyls, for example (n-butyl) (n-octyl) magnesium, can also be used as compounds (IVb). Any mixtures of compounds (IVb) can also be used.

As a strong neutral Lewis acid, alumoxane compounds are further preferred among the cocatalysts. In principle, those compounds which have an Al — C bond are suitable as alumoxane compounds. Particularly suitable as cocatalysts are open-chain and / or cyclic alumoxane compounds of the general formula (IVc) or (IVd)

in which
R ¹³ independently of one another denotes a C ₁ to C ₄ alkyl group, preferably a methyl or ethyl group, and r represents an integer from 5 to 30, preferably 10 to 25.

These oligomeric alumoxane compounds are prepared usually by reacting a solution of trialkyl aluminum with water and is u. a. in EP-A 0 284 708 and US-A 4,794,096.

As a rule, the oligomeric alumoxane obtained in this way compounds as mixtures of different lengths, both linear as well as cyclic chain molecules, so that r is the mean can be seen. The alumoxane compounds can also be mixed with other metal alkyls, preferably with aluminum alkyls, such as Triisobutylaluminium or Triethylaluminium exist. Prefers is methylalumoxane (MAO), especially in the form of a solution in Toluene used. The production of methylalumoxane can be found e.g. B. described in detail in EP-A 284 708.

Aryloxyalumoxanes, as described in US Pat US-A 5,391,793, amidoaluminoxanes as described in US Pat US-A 5,371,260, aminoaluminoxane hydrochlorides as described in EP-A 0 633 264, siloxyaluminoxanes as described in the EP-A 0 621 279 described, or alumoxane mixtures used become.

The alumoxanes described are either as such or in Form of a solution or suspension, for example in aliphati or aromatic hydrocarbons, such as toluene or Xy lol, or mixtures thereof.  

The cocatalysts described can either as such or can be used in any mixture.

The inventive method for the production of highly branched Polyolefins can be used in both a nonpolar or aliphatic aromatic aprotic solvent, e.g. B. in heptane, 1-butane, Toluene or benzene, as well as in a polar aprotic Solvents are carried out. Suitable polar aprotic Solvents are e.g. B. halogenated hydrocarbons such as Dichloromethane, chloroform, carbon tetrachloride or chlorobenzene as well as linear or cyclic ethers such as diethyl ether or tetrahydrofuran, furthermore acetone, dimethyl sulfoxide, Dimethylformamide, hexamethylphosphoric triamide or aceto nitrile. Of course, any mixtures of the aforementioned solvents can be used as long as these Mixes behave homogeneously. Dichloro is particularly preferred methane, toluene, i-butane, pentane, heptane, chlorobenzene and aceto nitrile and mixtures thereof, in particular toluene, i-butane and Chlorobenzene.

The amount of solvent is usually measured so that the Starting compounds at the beginning of the reaction in dissolved form lie.

The oligomerization after step a) is usually carried out at Tempe temperatures in the range of -40 to 160 ° C, preferably in the range of -20 to 100 ° C and particularly preferably from 0 to 80 ° C. The reaction times are generally dependent on the selected reaction conditions between 0.1 to 120 minutes.

The oligomerization generally takes place at a pressure in the loading range from 0.1 to 1000 bar, preferably from 0.5 to 100 bar and be particularly preferably in the range from 1 to 80 bar instead.

The concentration of transition metal compound (I) is generally set to values in the range from 10 ^-9 to 0.1, preferably from 5 × 10 ^-8 to 10 ^-2 and particularly preferably from 10 ^-6 to 5 × 10 ^-2 mol / l set.

The starting concentration of ethene is usually in the range from 10 ^-3 to 10 mol / l, preferably in the range from 10 ^-2 to 5 mol / l.

One or more transition metal compounds of the general formula (II) are added to the reaction mixture after step a). Preferred transition metal compounds are based on compounds (II) in which
M ^II titanium or zirconium,
R ⁹ to R ^{12 are} C ₁ to C ₁₀ alkyl or C ₃ to C ₂₁ organosilyl, where two adjacent radicals optionally form a condensed aromatic cycle,
T ', Q' is a hydrogen atom, a C ₁ to C ₁₀ alkyl or C ₆ to C ₂₀ aryl radical, a halogen atom, -OR ', -SR', -OSiR ' ₃ , -SiR' ₃ , -CR " ₂ SiR ' ₃ , e.g. -CH ₂ SiMe ₃ , -PR' ₂ , -NR ' ₂ , e.g. -NMe ₂ , toluenesulfonyl, trifluoroacetyl, trifluoromethanesulfonyl, nonafluorobutanesulfonyl, 2,2,2-tri fluoroethanesulfonyl,
Z CH ₂ , CH ₂ CH ₂ , CH (CH ₃ ) CH ₂ , CH (C ₄ H ₉ ) C (CH ₃ ) ₂ , C (CH ₃ ) ₂ , (CH ₃ ) ₂ Si, (CH ₃ ) ₂ Ge, (CH ₃ ) ₂ Sn, (C ₆ H ₅ ) ₂ Si, (C ₆ H ₅ ) (CH ₃ ) Si, (C ₆ H ₅ ) ₂ Sn, (CH ₂ ) ₄ Si or CH ₂ Si ( CH ₃ ) ₂ ,
k 1, 2 or 3,
G -O-, -S-, -NR "- or -PR" or a radical of the formula (III)

in which the substituents R ⁹ to R ^{12 have} the aforementioned meaning, and
R "is methyl, ethyl, n- or i-propyl, n-, i- or t-butyl, cyclohexyl or phenyl or cyclopentadienyl, 3-methyl cyclopentadienyl, 3-n-butylcyclopentadienyl, indenyl, tetrahydroindenyl, tetramethylcyclopentadienyl, 3-tri methylsilylcyclopentadienyl or 3-phenylcyclopenta dienyl, or
Z _k and G together represent a substituted or unsubstituted aromatic or heteroaromatic structure of 4 to 10 ring carbon atoms or
Z _k and R ⁹ and / or R ¹² together form a mono- or polycyclic aliphatic, aromatic or heteroaromatic ring system
mean.

As the central metal M ^II in the transition metal compounds (II) come early transition metals, ie those of group (IIIB), the group of lanthanoids, e.g. B. lanthanum or yttrium, the group IVB, z. B. titanium, zirconium or hafnium, the group VB, z. B. Va nadium, or the group VIB of the periodic table of the elements, for. As chromium or molybdenum, in question (see also textbook of inorganic chemistry, Holleman-Wiberg, de Gruyter Berlin, 1985). Preference is given to titanium, zirconium or hafnium. For the latter case, the metals M ^II are in the mononuclear complexes (II) generally formally four times positively charged.

As a monoanionic η ⁵ -bound cyclic ligand bearing the substituent - (Z _k ) -, in addition to cyclopentadienyl (R ⁹ -R ¹² = H), there are also simply negatively charged five-membered aromatic carbocycles which, in addition to the radical Z, are mono- or multiply are substituted with functional groups, for example with halogen such as fluorine, chlorine or bromine, linear or branched C ₁ -C ₂₀ -alkyl, preferably C ₁ -C ₁₀ -alkyl, such as methyl, ethyl, n-propyl, i-propyl , n-butyl or t-butyl, C ₃ to C ₁₀ cycloalkyl, preferably C ₃ to C ₇ cycloalkyl, such as cyclopropyl or cyclohexyl, or C ₆ to C ₁₆ aryl, preferably C ₆ to C ₁₀ Aryl, such as phenyl or naphthyl. Suitable aryl substituents include z. B. also with C ₁ - to C ₆ -alkyl such as methyl or i-propyl or with C ₆ - to C ₁₆ -aryl substituted by halogen such as fluorine, chlorine or bromine, preferably C ₆ - to C ₁₀ -aryl.

Two adjacent residues, e.g. B. R ⁹ and R ¹⁰ or R ¹⁰ and R ¹¹ , can also together form a 4 to 18, preferably 4 to 15 carbon atoms, saturated or unsaturated cyclic or heterocyclic group. This includes, for example, condensed aryl units. Accordingly, even substituted and unsubstituted indenyl, fluorenyl or benzindenyl systems are suitable monoanionic η ⁵ -bound cyclic ligands.

furthermore suitable radicals R ⁹ to R ^{12 are} C ₃ - to C ₃₀ -, preferably C ₃ - to C ₂₁ -organosilyl groups, -Si (R *) ₃ . The radicals R * can independently of one another C ₁ - to C ₁₀ -alkyl, preferably C ₁ - to C ₇ -alkyl, for. As methyl, ethyl or i-propyl, C ₃ - to C ₁₀ cycloalkyl, preferably C ₃ - to C ₇ cycloalkyl, e.g. B. cyclopropyl or cyclohexyl, C ₆ - to C ₁₀ aryl, preferably phenyl, or alkylaryl with up to 4 carbon atoms in the alkyl and 6 to 10 carbon atoms in the aryl part, for example benzyl.

The radicals R ⁹ to R ¹² in a compound (II) can have meanings which differ from one another and which differ from one another.

As the metal M ^II complexing, η ⁵ -bonded ligands among the aforementioned compounds, those are particularly suitable which are derived from cyclopentadienyl, tetra-C ₁ - to C ₆ -alkylcyclopentadienyl, indenyl, fluorenyl or benzindenyl, the latter three ligands can also be substituted one or more times with C ₁ - to C ₆ -alkyl groups. Accordingly, preferred radicals bearing the Z substituent are cyclopentadienyl, tetra-C ₁ -C ₄ -alkylcyclopentadienyl, indenyl, benzindenyl and 1 to 3-fold C ₁ -C ₄ -alkyl-substituted indenyl or benzindenyl. Cyclo pentadienyl, tetramethylcyclopentadienyl or indenyl, in particular tetramethylcyclopentadienyl, is particularly preferably used.

Usually complexes (II) are used that have two η ⁵ -bonded ligands. In these connections, G represents one. The rest of the formula (III). The η ⁵ -bonded ligands can be identical in their substitution pattern or also differ from one another in their ring system as such and / or their ring substitution pattern.

Suitable radicals Z are bivalent structural units based on monatomic bridge members, the free valences of which may be saturated by organic radicals R '. Suitable as bridge members are, for example, the silylene- (-SiR ' ₂ -), alkylene- (-CR' ₂ -), Germanyl- (-GeR ' ₂ -), stannyl- (-SnR' ₂ -), boronyl- (-BR'-) or the oxo group (-O-). Two covalently linked units Z (k = 2) can also form a bridge segment between the monoanionic η ⁵ -bonded ligand and the unit G. In a two-part bridge segment, Z does not necessarily have to be in the form of two identical structural units. Among the two-part bridge segments are in particular the systems -SiR ' ₂ -SiR' ₂ -, -SiR ' ₂ -CR' ₂ -, -CR ' ₂ -CR' ₂ -, -CR '= CR'-, -O-CR ' ₂ - and -O-SiR' ₂ - in question. However, preference is given to using one-atom bridging bridge segments (k = 1), in particular to the systems -SiR ' ₂ - and -CR' ₂ -. The radicals R 'can be C ₁ to C ₂₀ alkyl, preferably C ₁ to C ₁₀ alkyl, for example methyl, ethyl or i-propyl, C ₃ to C ₁₀ cycloalkyl, preferably C ₃ to C ₇ Cycloalkyl, for example cyclohexyl, C ₆ - to C ₁₅ aryl, preferably C ₆ - to C ₁₀ aryl, in particular phenyl, or alkylaryl with 1 to 10 C atoms in the alkyl and 6 to 10 C atoms in the aryl part, for Example benzyl mean. Z can also form a mono- or polycyclic aliphatic, aromatic or heteroaromatic ring system with one or more radicals R ⁹ to R ¹² . Among the radicals Z, di-C ₁ -C ₇ -alkyl-substituted silyl groups such as dimethylsilyl, diethylsilyl or di-i-propylsilyl are particularly preferred.

The unit G also includes, for example, the oxo (-O-), thio- (-S-), amido ((-NR "-) or the phosphido group (-PR" -). These groups are generally covalently and / or coordinatively linked to the metal center M ^II . Furthermore, G can also mean a neutral two-electron donor such as -OR ", -SR", -NR " ₂ or -PR" ₂ . The last-mentioned residues G mostly have a coordinative connection to the metal center M via a free electron pair. G preferably represents an oxo or thio group, particularly preferably an amido unit. Substitutes R "in the radicals -NR" -, -PR "-, -OR", -SR ", -NR" ₂ or -PR " ₂ is generally a hydrogen atom, C ₁ - to C ₂₀ -alkyl, for example methyl, ethyl, t-butyl or n-octyl, C ₃ - to C ₁₀ -cycloalkyl, for example cyclohexyl, C ₆ - bis C ₁₅ aryl, for example phenyl or naphthyl, C ₄ to C ₁₆ heteroaryl, for example pyridyl, furyl or quinolyl, alkylaryl with 1 to 10 C atoms in the alkyl and 6 to 10 C atoms in the aryl part, or C ₃ - to C ₃₀ organosilyl, eg trimethylsilyl. Particularly suitable radicals R "are sterically demanding groups such as C ₃ - to C ₁₀ -alkyl groups, for example i-propyl or t-butyl, the C ₆ to C ₁₀ aryl group such as phenyl or substituted phenyl, and the alkylaryl group with 1 to 6 C atoms in the alkyl and 6 to 10 C atoms in the aryl part, for example benzyl. -N (t-butyl-) is used particularly frequently as unit G. Furthermore, the unit G together with the unit Z or Z _{k can form} a substituted or unsubstituted aromatic or heteroaromatic structure of 4 to 16, preferably 4 to 10 ring carbon atoms.

The radicals T 'and Q' in compounds (II) can be the same in general assume my meaning as for the corresponding residues T and Q described in formula (I). T 'and Q' preferably represent Halides, preferably chloride or bromide, especially chloride represents.

In connection with suitable transition metal compounds (II) hereby expressly refers to the disclosure of DE-A 197 07 236 referred.

Particularly preferred as compounds (II) are dimethylsilanediyl bis (2-methyl-4- (1-naphthyl) indenyl) zirconium dichloride, dimethylsilanediylbis (indenyl) zirconium dichloride, dimethylsilanediyl bis (2-methylindenyl) zirconium dichloride, dimethylsilanediyl bis (2-methyldilane) ] indenyl) zirconium dichloride, [dimethylsilane dyl (tetramethylcyclopentadienyl) (t-butyl) amido] titanium dichloride,
(Quinolin-8-yl) -2-indenyl titanium (trichloride),
(Quinolin-8-yl) -2-indenyl-titanium (trimethyl),
(Quinolin-8-yl) -2-indenyl titanium (dichloride),
(Quinolin-8-yl) -2-benz [e] indenyl titanium (trichloride),
(Quinolin-8-yl) -2-benz [e] indenyl titanium (trimethyl),
(Quinolin-8-yl) -2-benz [e] indenyl-titanium (dichloride), (2-methyl-quinolin-8-yl) -2,3,4,5-tetramethyl-cyclopentadienyl-titanium (trichloride ), (2-methyl-quinolin-8-yl) -2,3,4,5-tetramethyl-cyclopenta dienyl-titanium (trimethyl) and (2-methyl-quino lin-8-yl) -2,3,4 , 5-tetramethyl-cyclopentadienyl titanium (dichloride).

The polymerization according to step b) can be initiated on the one hand be passed that the transition metal compound (II) to Re action mixture after step a), on the other hand, before addition the compound (II) the reaction mixture by adding further Solvent components are diluted. Furthermore, the Transition metal compound (II) both as such and in ge dissolved form, possibly together with another cocatalyst of the type described above, are added to the reaction mixture.

In step b), preference is given to methyl as cocatalysts alumoxan, magnesium, lithium or aluminum alkyl, e.g. B. Butyl octylmagnesium, butyllithium or triisobutylaluminium, or be any mixtures of these compounds with boranes and / or bora such as tris (pentafluorophenyl) borane or dimethylanilinium tetra kis (pentafluorophenyl) borate added.

The polymerization process after step b) is customary in the temperature range from -100 to 300 ° C, is preferred 0 to 200 ° C and particularly preferably from 25 to 150 ° C and in a pressure range of 0.5 to 300 bar, preferably 1 to 100 bar and particularly preferably carried out from 1 to 60 bar.

The method according to the invention can be carried out in only one Reactor as well as in two or more cascaded Reactors take place. About the addition of transition metal ver bonds (I) and (II) to the respective reactor cascades their ratio can be varied during the manufacturing process. The ratio of the compounds (I) to (II) is in general in the range from 200: 1 to 1:50 and preferably in the range from 50: 1 to 1:10.  

It has a particularly advantageous effect on the number of alkylver branches out if in process step b) the ethene supply ge stops and among those resulting from reaction step a) Printing conditions using the remaining amount of ethene Polymerization is continued. Of course you can too only in the course of process step b) the ethene supply ge be stopped. In a further embodiment, according to interruption of the ethene supply in step b) Course of the polymerization resumed.

The (co) polymerization reaction after step b) can be carried out in the usual way Way interrupted and worked up. For example the reaction mixture into an excess of low molecular weight Alcohol such as methanol, ethanol or i-propanol and given by Treat with a dilute mineral acid, e.g. B. hydrochloric acid, ge possibly in a mixture with a low molecular weight alcohol be felled.

The method according to the invention is reproducibly high branched polyolefins obtained with at least 120, in particular at least 150, preferably at least 170 and particularly preferred at least 205 alkyl branches / 1000 carbon atoms in the polymer back ridge.

The polyolefins obtained by the process according to the invention have average molecular weights M _w in the range from 10,000 to 2,000,000, preferably from 15,000 to 1,000,000 and particularly preferably from 20,000 to 500,000 g / mol. The polydispersities are in the range from 1.5 to 5.0, preferably from 1.5 to 3.0 and particularly preferably from 1.6 to 2.5.

The high ver Branched polymers are further characterized in that they a high proportion of ethyl branches, none or almost none Methyl branches and small amounts of butyl and hexyl or have higher branches. Are preferred with the receive highly branched polyolefins according to the process of the invention, their alkyl branches to at least 60, preferably at least 70 and particularly preferably at least 80% on ethyl side branches and to a maximum of 20, preferably a maximum of 15 and particularly preferred represents a maximum of 10% on butyl, hexyl and higher side branches put.  

The highly branched polyolefins obtained have a elastomeric property profile and are usually complete amorphous. They show no melting points and show glass transition temperature values that are regularly below -10, preferably -30 and are particularly preferably below -50 ° C.

The high ver branched polyolefins are suitable for. B. for impact modification of linear polyolefins or of polymer mixtures from thermo plastically processable materials. Suitable thermoplastic Materials are, for example, polyamides such as so-called poly amide 6 or polyamide 6.6, polyacetals such as polyoxymethylene or Polyesters such as polybutylene terephthalate.

According to the method according to the invention, no dimeric copper Planning products from the 1-alkenes prepared observed. Except between the olefin oligomerization and Polymerization catalysts have no interfering interactions detected. Furthermore, ver branched polyolefins no unreacted, in step a) ge detected 1-alkenes, d. H. these connections are in Step b) completely incorporated into the polymer chain, so that a uniform product is obtained.

The invention is illustrated by the following examples explained.

Examples

Gel permeation chromatography of the polymer from experiment 9 was on a device from Waters (150 C) with 1,2,4-trichlor benzene as eluent (flow rate: 1 ml / min) against polyethylene standards at 140 ° C according to DIN 55 672.

Gel permeation chromatography of the polymers from the experiments 1-6 with tetrahydrofuran as eluent (flow rate: 1.2 ml / min) performed against polystyrene standards at 35 ° C.

The ¹ H-NMR and ¹³ C-NMR spectra were recorded on a device from Bruker (ARX 300) with CD ₂ Cl ₄ as solvent.

The DSC spectra were recorded on a device from Perkin-Elmer (Series 7) at a heating rate of 20 K / min.

Tetrahydrofuran and toluene were added over sodium / benzophenone Reflux heated and distilled under inert gas.  

Methylalumoxane (MAO) was added as a 1.53 molar solution in toluene set. It is a commercially available one Product from Witco.

The preparation of the catalyst complexes (Ia, Ib) and (II) as the polymerization reactions were also carried out with the exclusion of Air and moisture as well as using in the metal organic chemistry known protective gas techniques with nitrogen performed as a protective gas.

A. Preparation of the catalyst complexes 1. Transition metal compounds (Ia, Ib) a) 2,6-bis- [1- (2-methylphenylimino) ethyl)] pyridine

2,6-diacetylpyridine (1.5 g), 2-methylaniline (2.1 g) and p-To luenesulfonic acid (160 mg) was purified using a Water separator in benzene (50 ml) under reflux for 24 h is heating. The cooled reaction mixture was with diethyl ether (100 ml) diluted and with aqueous sodium hydrogen carbonate Washed solution (100 ml) and water (100 ml). The organic Phase was dried over sodium sulfate and in a vacuum narrowed. The residue obtained was washed with cold methanol (50 ml) washed and dried in vacuo. The yield at yellow solid was 80%.

(b) 2,6-bis- [1- (phenylimino) ethyl)] pyridine

The above-mentioned ligand was synthesized analogously to Regulation according to A.1.a) with the difference that instead of 2-methylaniline aniline (1.86 g) was used. The yield was 82%.

c) transition metal compounds (Ia) (comparative catalyst) and (Ib) (catalyst according to the process of the invention)

2,6-bis- [1- (2-methylphenylimino) ethyl)] pyridine (A.1.a)) and 2,6-bis- [1- (phenylimino) ethyl)] pyridine (A.1 .b)) (1 mmol), dissolved in tetrahydrofuran (10 ml), with stirring to FeCl ₂ .4 H ₂ O (1.0 mmol) in tetrahydrofuran (10 ml). After stirring at RT for two hours, the volatile components were removed in vacuo and the residue was washed with diethyl ether (50 ml) and n-pentane (50 ml). The last solvent residues were removed in a high vacuum. The products (Ia) and (Ib) were each obtained in almost quantitative yield.

2) transition metal compound (II) Dimethylsilanediyl bis (2-methyl-4- (1-naphthyl) indenyl) zirconium dichloride

The aforementioned transition metal compound (II) was according to the regulation by Spaleck et al., Organometallics 1994, 13, 954-963.

a.) Production of highly branched polyolefins

In a 2.0 l (experiments 1-6) or 1.6 l (experiments 7-9) pressure autoclave containing toluene (experiments 1-6: 1000 ml, experiments 7-9: 800 ml) and methylalumoxane (1st , 53 molar solution in toluene) were added with stirring (600 rpm) at a temperature of 40 ° C., the transition metal compound (Ib) or (Ia), the reaction vessel having been flushed with ethene gas beforehand. The ethene pressure was set to 2 bar and kept constant at this pressure during the first reaction phase (step a). The ethene feed was interrupted before the addition of the transition metal compound (II). After addition of the transition metal compound (II), the polymerization reaction was carried out using the ethene in the reaction vessel (step b)). After cooling to room temperature, the reaction vessel was let down and the polymer solution was slowly introduced into 200 ml of ethanol, the reaction mixture was concentrated to a volume of approx. 400 ml and the polymer product was then dissolved in an excess of a mixture of dilute hydrochloric acid and methanol (approx. 1.5 l) fails. The filtered product was washed with methanol (300 ml) and freed from the last solvent residues in a high vacuum at 40 ° C. More detailed information on the reaction parameters of the polymerizations carried out according to this general rule and the product properties of the polymers produced can be found in the table below.

• a) In the polyolefins obtained according to experiments 1 to 6, the alkyl branches mentioned are ethyl (80%), butyl (10%) and hexyl and higher side branches (10%); determined by means of ¹³ C-NMR spectroscopy;
• b) First numerical value = reaction time for step a), second Numerical value = reaction time for step b);
• c) comparative tests;
• d) polymerization in the presence of the Catalysts (Ib) and (II) (This experiment demonstrates that with simultaneous use of catalysts Ib) and (II), d. H. when steps a) and b) are carried out simultaneously, not highly branched amorphous polyolefins can be obtained).

Claims (6)

1. A process for the homogeneous catalytic preparation of highly branched amorphous polyolefins with an elastomeric property profile from ethene, characterized in that in a first step

• a) ethene in the presence of at least one transition metal compound of the general formula (I)
  in which the substituents and indices have the following meaning:
  R ¹ , R ² C ₄ to C ₁₆ heteroaryl or C ₆ to C ₁₆ aryl with hydrogen substituents in the two vicinal positions to the point of connection between aryl or heteroaryl and N ^a or N ^b ,
  R ³ , R ^{4 are} hydrogen, C ₁ - to C ₁₀ -alkyl, C ₃ - to C ₁₀ -cycloalkyl, C ₆ - to C ₁₆ -aryl, alkylaryl with 1 to 10 C atoms in the alkyl and 6 to 14 C atoms in the aryl part or Si (R ⁸ ) ₃ with
  R ^{5 is} C ₁ to C ₁₀ alkyl, C ₃ to C ₁₀ cycloalkyl, C ₆ to C ₁₆ aryl, alkylaryl with 1 to 10 C atoms in the alkyl and 6 to 14 C atoms in the aryl part,
  R ⁵ , R ⁶ , R ^{7 are} hydrogen, C ₁ - to C ₁₀ -alkyl, C ₃ - to C ₁₀ -cyclo alkyl, C ₆ - to C ₁₆ -aryl, alkylaryl with 1 to 10 C atoms in the alkyl and 6 to 14 carbon atoms in the aryl part or Si (R ⁸ ) ₃ or functional groups based on the elements of groups IVA to VIIA of the Periodic Table of the Elements or R ⁵ and R ⁶ and / or R ⁶ and R ⁷ together form one fused five-, six- or seven-membered aliphatic or aromatic, substituted or unsubstituted carbo- or heterocycle,
  M ^I Fe, Ru, Co, Rh, Ni or Pd
  T, Q neutral or monoanionic monodentate ligands or T and Q together form a diketoenolate unit or a C ₂ or C ₃ alkylene unit with a methyl ketone or a linear C ₁ to C ₄ alkyl ester or nitrile end group,
  A a non or poorly coordinating anion,
  m, p 0, 1, 2 or 3,
  q 1, 2 or 3 and
  n 1, 2 or 3
  and optionally one or more cocatalysts in the form of strong neutral Lewis acids, ionic compounds with a Lewis acidic cation or ionic compounds with a Bronsted acid as a cation in an inert solvent oligomerized in a further step
• b) at least one transition metal compound of the general formula (II)
  in which the substituents and indices have the following meaning:
  R ⁹ to R ^{12 are} hydrogen, C ₁ to C ₁₀ alkyl, C ₃ to C ₁₀ cycloalkyl, C ₆ to C ₁₆ aryl, alkylaryl having 1 to 10 C atoms in the alkyl and 6 to 14 C atoms in the aryl part or Si (R ⁸ ) ₃ or functional groups based on the elements of groups IVA to VIIA of the periodic table of the elements or R ⁹ and R ¹⁰ and / or R ¹¹ and R ¹² each together form an elliptical five-, six- or seven-membered aliphatic or aromatic, substituted or unsubstituted carbo- or heterocycle,
  M ^{II is} a metal from group IIIB, IVB, VB or VIB of the Periodic Table of the Elements,
  T ', Q' is a hydrogen atom, a C ₁ to X ₁₀ alkyl or C _{6 to} 020 aryl radical, a halogen atom, -OR ', -SR', -OSiR ' ₃ , -SiR' ₃ , -CR " ₂ SiR ' ₃ , -PR' ₂ , -NR ' ₂ , toluene sulfonyl, trifluoroacetyl, trifluoromethanesulfonyl, nonafluorobutanesulfonyl, 2,2,2-trifluoroethanesulfonyl,
  Z -CR ' ₂ -, -SiR' ₂ -, - GeR ' ₂ -, -SnR' ₂ -, -BR'- or- -O- with
  R 'C ₁ to C ₂₀ alkyl, C ₃ to C ₁₀ cycloalkyl, C ₆ to C ₁₆ aryl, alkylaryl having 1 to 10 C atoms in the alkyl and 6 to 10 C atoms in the aryl part, C ₁ to C ₂₀ alkoxy, C ₃ to C ₁₀ cycloalkoxy, C ₆ to C ₁₆ aryloxy or alkylaryloxy having 1 to 10 C atoms in the alkyl and 6 to 10 C atoms in the aryl part,
  k 1, 2 or 3,
  G -O-, -S-, -NR ", -PR", -BR "-, -OR" -, -SR "-, -NR" ₂ , -PR " ₂ or or a radical of the formula (III)
  in which the substituents R ⁹ to R ^{12 have} the abovementioned meaning,
  R "is hydrogen, C ₁ - to C ₂₀ -alkyl, C ₃ - to C ₁₀ -cyclo alkyl, C ₆ - to C ₁₅ -aryl, alkylaryl with 1 to 10 C-atoms in the alkyl and 6 to 10 C-atoms in the aryl part or C ₃ - to C ₃₀ organosilyl, or
  Z _k and G together form a substituted or unsubstituted aromatic or heteroaromatic structure of 4 to 16 ring carbon atoms or
  Z _k and R ⁹ and / or R ¹² together form a mono- or polycyclic aliphatic, aromatic or heteroaromatic ring system,
  and optionally further cocatalysts as described under step a) are added to the oligomerization mixture according to a) and the reaction is continued in the presence of ethene and then the polymer product obtained is isolated in step c).

2. The method according to claim 1, characterized in that one uses transition metal compounds (I) in which the substituents and indices have the following meaning:
R ¹ , R ² 4-i-propylphenyl, 4-methylphenyl, 4-methoxyphenyl or phenyl,
R ³ , R ^{4 are} hydrogen, methyl, ethyl, i-propyl, t-butyl or triorganosilyl,
R ⁵ , R ⁶ , R ^{7 are} hydrogen or methyl,
M ^I iron or cobalt and
T, Q halide ions or trifluoromethanesulfonate. 3. The method according to claims 1 or 2, characterized in that one uses transition metal compounds (I) in which the substituents and indices have the following meaning:
R ¹ , R ² 4-i-propylphenyl, 4-methylphenyl, 4-methoxyphenyl or phenyl,
R ³ , R ^{4 are} hydrogen, methyl, ethyl, i-propyl, t-butyl or triorganosilyl,
R ⁵ , R ⁶ , R ^{7 are} hydrogen or methyl,
M ^I iron or cobalt,
T methyl,
Q chloride, bromide or trifluoromethanesulfonate and
A tetrakis (3,5-bis-trifluoromethyl) phenyl) borate, B [C ₆ F ₅ ] ₄ -, BF ₄ -, SbF ₆ -, AlF ₄ - AsF ₆ -, PF ₆ - or tri fluoroacetate. 4. The method according to claims 1 to 3, characterized in that one uses transition metal compounds (II) in which the substituents and indices have the following meaning:
M ^II titanium or zirconium,
R ⁹ to R ^{12 are} C ₁ to C ₁₀ alkyl or C ₃ to C ₂₁ organosilyl, where two adjacent radicals may form a condensed aromatic cycle,
T ', Q' is a hydrogen atom, a C ₁ to C ₁₀ alkyl or C _{6 to} C ₂₀ aryl radical, a halogen atom, -OR ', -SR', -OSiR ' ₃ , -SiR' ₃ , -CR " ₂ SiR ' ₃ , -PR' ₂ , -NR ' ₂ , toluene sulfonyl, trifluoroacetyl, trifluoromethanesulfonyl, nonafluorobutanesulfonyl or 2,2,2-trifluoroethane sulfonyl,
Z CH ₂ , CH ₂ CH ₂ , CH (CH ₃ ) CH ₂ , CH (C ₄ H ₉ ) C (CH ₃ ) ₂ , C (CH ₃ ) ₂ , (CH ₃ ) ₂ Si, (CH ₃ ) ₂ Ge, (CH ₃ ) ₂ Sn, (C ₆ H ₅ ) ₂ Si, (C ₆ H ₅ ) (CH ₃ ) Si, (C ₆ H ₅ ) ₂ Sn, (CH ₂ ) ₄ Si or CH ₂ Si ( CH ₃ ) ₂ ,
k 1, 2 or 3,
G -O-, -S-, -NR "- or -PR" or a residue of the formula (III)
in which the substituents R ⁹ to R ^{12 have} the abovementioned meaning,
R "methyl, ethyl, n- or 1-propyl, n-, i- or t-butyl, cyclohexyl or phenyl or cyclopentadienyl, 3-methylcyclopentadienyl, 3-n-butylcyclopentadienyl, indenyl, tetrahydroindenyl, tetramethylcyclopentadienyl, 3- Trimethylsilylcyclopentadienyl or 3-phenylcyclopentadienyl. 5. The method according to claims 1 to 4, characterized in that as cocatalysts in steps a) and / or b) Boranes, magnesium, lithium or aluminum alkyls, aluminum halogen alkyls or alumoxanes used. 6. The method according to claims 1 to 5, characterized in net that the process steps a) and b) in one stir boiler cascade.