WO2023232613A1

WO2023232613A1 - Process for manufacturing of higher functional polyisobutenes

Info

Publication number: WO2023232613A1
Application number: PCT/EP2023/064002
Authority: WO
Inventors: Sergej KOSTJUK; Szilard Csihony; Paul Lederhose; Svenja WESP; Mikalai BOHDAN; Dmitryi SHIMAN; Irina V. VASILENKO
Original assignee: Basf Se
Priority date: 2022-06-03
Filing date: 2023-05-25
Publication date: 2023-12-07

Abstract

The present invention relates to a process for manufacturing of polyisobutenes with a function- ality fPIB of one or more than 1 in which iron halides are used as Lewis acid in a complex with certain donors.

Description

Process for Manufacturing of Higher Functional Polyisobutenes Description The present invention relates to a process for manufacturing of polyisobutenes with a function- ality f_PIB of one or more than 1 in which iron halides are used as Lewis acid in a complex with certain donors. Processes for manufacturing of polyisobutenes with a functionality f_PIB of more than 1 are known in the literature. For such processes initiators are used which bear one or more than one func- tionality with which a polymerisation can be started so that one or more than one polymer chains are started from those functionalities. Wu et al. (Yan, P.-F.; Guo, A.-R.; Liu, Q.; Wu, Y.-X. Living Cationic Polymerization of Isobutyl- ene Coinitiated by FeCl₃ in the Presence of Isopropanol. J. Polym. Sci.: Part A: Polym. Chem. 2012, 50, 3383–3392. DOI:10.1002/pola.26126) describe approximately difunctional chlorine- terminated polyisobutenes based upon di(2-chloro-2-propyl) benzene as initiator using FeCl3 as Lewis acid in the presence of isopropanol. Polymerisation was initiated by separately adding the solutions of FeCl3 and isopropanol in CH2Cl2 as solvent. It is a disadvantage of such manufacturing process that the thus obtained complex exhibits only little reactivity, presumably due to insufficient solubility of the FeCl3 in the solvent under the re- action conditions. Therefore, it was an object of the present invention to develop a manufacturing process which leads to polyisobutenes with a functionality fPIB of one or preferably more than 1 with a higher yield and/or shorter reaction times. This problem was solved by a process for manufacturing of polyisobutenes with a functionality fPIB of one or preferably more than 1 and a Mn of from 500 to 25000 g/mol, comprising the steps of - providing an initiator In with a functionality fIn of one or preferably more than 1 - providing an isobutene-containing monomer feedstock - polymerising the reaction mixture of initiator In and isobutene-containing monomer feedstock in the presence of an iron halide FeX3 , preferably iron chloride FeCl3 catalyst and at least one donor compound R¹-O-R², wherein R¹ and R² independently of another represent are an organic residue of up to 20 carbon atoms, preferably C₁- to C₂₀-alkyl, C₅- to C₈-cycloalkyl radical, C₆- to C₂₀-aryl radical or C₇- to C₂₀-ar- ylalkyl radical, or together with the oxygen atom may form a five-, six- or seven-membered ring, and R² additionally is hydrogen, X independently of another represents halide, characterised in that prior to the polymerisation iron halide and the at least one donor com- pound are brought together in a molar ratio of 1 : 1.1 to 1 : 1.9 forming a complex in the ab- sence of a isobutene-containing monomer feedstock and the thus formed complex is brought into contact with the isobutene-containing monomer feedstock. The advantages of the process according to the invention are as follows: - higher functional polyisobutenes can be obtained in high yield and/or short reaction times - the complex of iron halide and donor complex can be prepared in a separate step and can be stored at a certain maximum temperature without significantly losing its reactivity - the activity of the complex can be significantly increased by the addition of 10 to 20 mol% of H2O - Complexes of FeCl3 with donors show high activity at low concentrations (FeCl3/initiator <1) as compared to widely used TiCl4 - the reaction mixture can easily be converted into a product bearing olefinic end groups, preferably with a high content of alpha olefinic groups - the reaction mixture can easily be converted into e.g. hydroxy-group containing deriva- tives by reaction with phenols - further derivatives can be obtained by employing alkoxyaromates, wherein the alkoxy group may bear further functional groups (see below) Halide is fluoride, chloride, bromide or iodide, preferably fluoride, chloride or bromide, very pref- erably chloride or bromide and especially chloride. Among the halides X fluoride, chloride, and bromide are preferred, chloride and bromide more preferred and chloride is most preferred. Preferred iron halide FeX3 are FeBr3 and FeCl3, most preferred is iron chloride FeCl3. In the donor compound R¹-O-R² the residues R¹ and R² are independently of another an organic residue of up to 20 carbon atoms, preferably C₁- to C₂₀-alkyl, C₅- to C₈-cycloalkyl radical, C₆- to C₂₀-aryl radical or C₇- to C₂₀-arylalkyl radical, or together with the oxygen atom may form a five-, six- or seven-membered ring, and R² additionally is hydrogen. In a preferred embodiment the donor compound R¹-O-R² is an alcohol R¹-O-H, more preferably an alkanol. In the context of the present invention, the following definitions apply to generically defined radi- cals: A C1- to C8-alkyl radical is a linear or branched alkyl radical having 1 to 8 carbon atoms. Exam- ples thereof are methyl, ethyl, n-propyl, isopropyl, n-butyl, 2-butyl, isobutyl, tert-butyl, pentyl, 1- methylbutyl, 2-methylbutyl, 3-methylbutyl, 2,2-dimethyl-propyl, 1-ethylpropyl, n-hexyl, 1,1-dime- thylpropyl, 1,2-dimethylpropyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 1,1-dimethylbutyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl, 2,2-dimethylbutyl, 2,3-dimethylbutyl, 3,3- dimethylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1,1,2-trimethylpropyl, 1,2,2-trimethylpropyl, 1-ethyl-1- methylpropyl, 1-ethyl-2-methylpropyl, n-heptyl, n-octyl and the constitutional isomers thereof, such as 2-ethylhexyl. Such C1- to C8-alkyl radicals may to a small extent also comprise heteroa- toms such as oxygen, nitrogen or halogen atoms, for example chlorine, and/or aprotic functional groups, for example carboxyl ester groups, cyano groups or nitro groups. However, radicals purely consisting of carbon and hydrogen are preferred. A C1- to C4-alkyl radical is methyl, ethyl, n-propyl, isopropyl, n-butyl, 2-butyl, isobutyl or tert-bu- tyl. A C1- to C20-alkyl radical is a linear or branched alkyl radical having 1 to 20 carbon atoms. Ex- amples thereof are the abovementioned C1- to C8-alkyl radicals, and additionally n-nonyl, isononyl, n-decyl, 2-propylheptyl, n-undecyl, n-dodecyl, n-tridecyl, isotridecyl, n-tetradecyl, n- hexadecyl, n-octadecyl and n-eicosyl. Such C₁- to C₂₀-alkyl radicals may to a small extent also comprise heteroatoms such as oxygen, nitrogen or halogen atoms, for example chlorine, and/or aprotic functional groups, for example carboxyl ester groups, cyano groups or nitro groups. However, radicals purely consisting of carbon and hydrogen are preferred. A C5- to C8-cycloalkyl radical is a saturated cyclic radical which may comprise alkyl side chains. Examples thereof are cyclopentyl, 2- or 3-methylcyclopentyl, 2,3-, 2,4- or 2,5- dimethylcyclopentyl, cyclohexyl, 2-, 3- or 4-methylcyclohexyl, 2,3-, 2,4-, 2,5-, 2,6-, 3,4-, 3,5- or 3,6-dimethylcyclohexyl, cycloheptyl, 2-, 3- or 4-methylcycloheptyl, cyclooctyl, 2-, 3-, 4- or 5- methylcyclooctyl. Such C₅- to C₈-cycloalkyl radicals may to a small extent also comprise het- eroatoms such as oxygen, nitrogen or halogen atoms, for example chlorine, and/or aprotic func- tional groups, for example carboxyl ester groups, cyano groups or nitro groups. However, radi- cals purely consisting of carbon and hydrogen are preferred. A C₆- to C₂₀-aryl radical or a C₆- to C₁₂-aryl radical is preferably optionally substituted phenyl, optionally substituted naphthyl, optionally substituted anthracenyl or optionally substituted phe- nanthrenyl. Such aryl radicals may be a 1 to 5 aprotic substituents or aprotic functional groups, for example C1- to C8-alkyl, C1- to C8-haloalkyl such as C1- to C8-chloroalkyl or C1- to C8-fluoro- alkyl, halogens such as chlorine or fluorine, nitro, cyano or phenyl. Examples of such aryl radi- cals are phenyl, naphthyl, biphenyl, anthracenyl, phenanthrenyl, tolyl, nitrophenyl, chlorophenyl, dichlorophenyl, pentafluorophenyl, pentachlorophenyl, (trifluoromethyl)phenyl, bis(tri-fluorome- thyl)phenyl, (trichloro)methylphenyl and bis(trichloromethyl)phenyl. However, radicals purely consisting of carbon and hydrogen are preferred. A C7- to C20-arylalkyl radical or a C7- to C12-arylalkyl radical is preferably optionally substituted C1- to C4-alkylphenyl such as benzyl, o-, m- or p-methylbenzyl, 1- or 2-phenylethyl, 1-, 2- or 3- phenylpropyl or 1-, 2-, 3- or 4-phenylbutyl, optionally substituted C1- to C4-alkylnaphthyl such as naphthylmethyl, optionally substituted C1- to C4-alkylanthracenyl such as anthracenylmethyl, or optionally substituted C1- to C4-alkylphenanthrenyl such as phenanthrenylmethyl. Such arylalkyl radicals may bear 1 to 5 aprotic substituents or aprotic functional groups, especially on the aryl moiety, for example C1- to C8-alkyl, C1- to C8-haloalkyl such as C1- to C8-chloroalkyl or C1- to C8-fluoroalkyl, halogen such as chlorine or fluorine, nitro or phenyl. However, radicals purely consisting of carbon and hydrogen are preferred. Examples for such donor compounds are ethers, phenols and alcohols, preferably ethers and alcohols, more preferably alcohols. Alcohols as donors preferably are C₁-C₁₂-hydrocarbyl alcohols and preferably have only one hy- droxyl group per molecule. Particularly suitable C1-C12-hydrocarbyl alcohols are linear or branched C1-C12-alkanols, preferably linear or branched C1-C8-alkanols, very preferably linear or branched C1-C6-alkanols, especially linear or branched C1-C4-alkanols, C5-C12-cycloalkanols and C7-C12-aryl alkanols. Typical examples of such compounds are methanol, ethanol, n-propa- nol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, n-pentanol, sec-pentanol, tert- pentanol, n-hexanol, n-heptanol, n-octanol, 2-ethylhexanol, n-nonanol, n-decanol, 2-propylheptanol, n-undecanol, n-dodecanol, cyclopentanol, cyclohexanol, 2-, 3- or 4-methylcy- clohexanol, cycloheptanol, benzyl alcohol, 1- or 2-phenylethanol, 1-, 2- or 3-phenylpropanol, 1-, 2-, 3- or 4-phenylbutanol, (o-, m- or p-methylphenyl)methanol, 1,2-ethylene glycol, 1,3-propyl- ene glycol, 1,2,3-propanetriol (glycerol), 1,2-ethylene glycol monomethyl ether, 1,2-ethylene gly- col monoethyl ether, 1,3-propylene glycol monomethyl ether and 1,3-propylene glycol mo- noethyl ether. It is also possible to use mixtures of various C₁-C₁₂-hydrocarbyl alcohols of this type. Particular preference is given to using branched and in particular linear C₁-C₁₂-alkanols, prefera- bly linear or branched C₁-C₈-alkanols, very preferably linear or branched C₁-C₆-alkanols, espe- cially linear or branched C1-C4-alkanols. Preferred examples are methanol, ethanol, n-propanol, iso-propanol, n-butanol, iso-butanol, sek-butanol and tert-butanol, more preferably methanol, ethanol, iso-propanol, n-butanol, and iso-butanol, even more preferably methanol, ethanol, iso-propanol, and n-butanol, and most preferably iso-propanol. Ethers as donors preferably mean dihydrocarbyl ethers of the general formula R¹-O-R² in which the variables R¹ and R² are each independently C1- to C20-alkyl radicals, preferably C1- to C8 al- kyl radicals especially C1- to C4 alkyl radicals, C5- to C8-cycloalkyl radicals, preferably C5- to C6- cycloalkyl radicals, C6- to C20-aryl radicals, especially C6- to C12 aryl radicals, or C7- to C20-ar- ylalkyl radicals, especially C7- to C12-arylalkyl radicals. Furthermore, C1- to C8 haloalkyl radicals, preferably C1- to C8 chloroalkyl radicals are possible. Preference is given to C1- to C4 alkyl radi- cals, C6- to C12 aryl radicals, and C7- to C12-arylalkyl radicals. The dihydrocarbyl ethers mentioned may be open-chain or cyclic, where the two variables R¹ and R² in the case of the cyclic ethers may join to form a ring, where such rings may also com- prise two or three ether oxygen atoms. Examples of such open-chain and cyclic dihydrocarbyl ethers are dimethyl ether, diethyl ether, di-n-propyl ether, diisopropyl ether, di-n-butyl ether, di- sec-butyl ether, diisobutyl ether, di-n-pentyl ether, di-n-hexyl ether, di-n-heptyl ether, di-n-octyl ether, di-(2-ethylhexyl) ether, methyl n-butyl ether, methyl sec-butyl ether, methyl isobutyl ether, methyl tert-butyl ether, ethyl n-butyl ether, ethyl sec-butyl ether, ethyl isobutyl ether, ethyl tert- butyl ether, n-propyl-n-butyl ether, n-propyl sec-butyl ether, n-propyl isobutyl ether, n-propyl tert- butyl ether, isopropyl n-butyl ether, isopropyl sec-butyl ether, isopropyl isobutyl ether, isopropyl tert-butyl ether, methyl n-hexyl ether, methyl n-octyl ether, methyl 2-ethylhexyl ether, ethyl n- hexyl ether, ethyl n-octyl ether, ethyl 2-ethylhexyl ether, n-butyl n-octyl ether, n-butyl 2- ethylhexyl ether, tetrahydrofuran, tetrahydropyran, 1,2-, 1,3- and 1,4-dioxane, dicyclohexyl ether, diphenyl ether, alkyl aryl ethers, such as anisole and phenetole, ditolyl ether, dixylyl ether and dibenzyl ether. Furthermore, bis (2-chloroethyl) ether, 2-chloroethyl ethyl ether, 2-chloro- ethyl methyl ether, chloromethyl methyl ether, and chloromethyl ethyl ether are possible. Furthermore, difunctional ethers such as dialkoxybenzenes, preferably dimethoxybenzenes, very preferably veratrol, and ethylene glycol dialkylethers, preferably ethylene glycol di- methylether and ethylene glycol diethylether, are preferred. Among the dihydrocarbyl ethers mentioned, diethyl ether, diisopropyl ether, di-n-butyl ether and diphenyl ether have been found to be particularly advantageous as donors for the hydro- carbyloxy aluminum compound-donor complexes or mixtures of hydrocarbyloxy aluminum com- pounds-donor complexes. In a further embodiment a mixture of dihydrocarbyl ethers comprises at least one ether with pri- mary dihydrocarbyl groups and at least one ether with at least one secondary or tertary dihydro- carbyl group. Ethers with primary dihydrocarbyl groups are those ethers in which both dihydro- carbyl groups are bound to the ether functional group with a primary carbon atom, whereas ethers with at least one secondary or tertary dihydrocarbyl group are those ethers in which at least one dihydrocarbyl group is bound to the ether functional group with a secondary or tertiary carbon atom. For the sake of clarity, e.g. diisobutyl ether is deemed to be an ether with primary dihydrocarbyl groups, since the secondary carbon atom of the isobutyl group is not bound to the oxygen of the functional ether group but the hydrocarbyl group is bound via a primary carbon atom. Preferred examples for ethers with primary dihydrocarbyl groups are diethyl ether, di-n-butyl ether, and di-n-propyl ether. Preferred examples for ethers with at least one secondary or tertary dihydrocarbyl group are diisopropyl ether, methyl tert-butyl ether, ethyl tert-butyl ether, and anisole. Preferred mixtures of ethers acording to the invention are diethyl ether/diisopropyl ether, diethyl ether/methyl tert-butyl ether, diethyl ether/ethyl tert-butyl ether, di-n-butyl ether/diisopropyl ether, di-n-butyl ether/methyl tert-butyl ether, and di-n-butyl ether/ethyl tert-butyl ether. Very preferred mixtures are diethyl ether/diisopropyl ether, di-n-butyl ether/diisopropyl ether, diethyl ether/me- thyl tert-butyl ether, and di-n-butyl ether/ethyl tert-butyl ether, the mixture of diethyl ether/diiso- propyl ether being especially preferred. The initiators are molecules bearing groups reactive with the iron halide under the reaction con- ditions, for example tert-alkyl-, benzyl- or allyl halides, -esters or -ethers, preferably halides, more preferably chlorides or bromides, even more preferably chlorides. The functionality of the initiators f_In may be one or more than 1, preferably 2 or more, and more preferably 2. The functionality f_In is the number of groups reactive with the iron halide under the reaction conditions employed, preferably the number of halides in the initiator molecule bound to tertiary, allylic or benzylic carbon atoms, and more preferably the number chloride and/or bro- mide groups in the molecule, especially chloride. Initiators bearing one functional group (fIn = 1) are selected from organic hydroxyl compounds, organic halogen compounds and water, preferably organic halogen compounds. It is also possi- ble to use mixtures of the initiators mentioned, for example mixtures of two or more organic hy- droxyl compounds, mixtures of two or more organic halogen compounds, mixtures of one or more organic hydroxyl compounds and one or more organic halogen compounds, mixtures of one or more organic hydroxyl compounds and water, or mixtures of one or more organic halo- gen compounds and water. According to the invention organic halogen compounds as initiators with FeCl3 lead to a faster polymerisation reaction than the corresponding alcohols or water as initiators, therefore, the or- ganic halogen compounds are preferred as initiators. Organic hydroxyl compounds which have only one hydroxyl group in the molecule and are suit- able as monofunctional initiators include especially alcohols and phenols, in particular those of the general formula R¹²-OH, in which R¹² denotes C1- to C20-alkyl radicals, especially C1- to C8- alkyl radicals, C5- to C8-cycloalkyl radicals, C6- to C20-aryl radicals, especially C6- to C12-aryl rad- icals, or C - to C -arylalkyl radicals, especially C - to C -aryla 12 7 20 7 12 lkyl radicals. In addition, the R radicals may also comprise mixtures of the abovementioned structures and/or have other func- tional groups than those already mentioned, for example a keto function, a nitroxide or a car- boxyl group, and/or heterocyclic structural elements. Typical examples of such organic monohydroxyl compounds are methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, isobutanol, tert-butanol, n-pentanol, n-hexanol, n-heptanol, n-octanol, 2-ethylhexanol, cyclohexanol, phenol, p-methoxyphenol, o-, m- and p-cresol, benzyl alcohol, p-methoxybenzyl alcohol, 1- and 2-phenylethanol, 1- and 2-(p-methoxyphenyl)ethanol, 1-, 2- and 3-phenyl-1-propanol, 1-, 2- and 3-(p-methoxyphenyl)-1-propanol, 1- and 2-phenyl-2- propanol, 1- and 2-(p-methoxyphenyl)-2-propanol, 1-, 2-, 3- and 4-phenyl-1-butanol, 1-, 2-, 3- and 4-(p-methoxyphenyl)-1-butanol, 1-, 2-, 3- and 4-phenyl-2-butanol, 1-, 2-, 3- and 4-(p-me- thoxyphenyl)-2-butanol, 9-methyl-9H-fluoren-9-ol, 1,1-diphenylethanol, 1,1-diphenyl-2-propyn-1- ol, 1,1-diphenylpropanol, 4-(1-hydroxy-1-phenylethyl)benzonitrile, cyclopropyldiphenylmethanol, 1-hydroxy-1,1-diphenylpropan-2-one, benzilic acid, 9-phenyl-9-fluorenol, triphenylmethanol, di- phenyl(4-pyridinyl)methanol, alpha,alpha-diphenyl-2-pyridinemethanol, 4-methoxytrityl alcohol (especially polymer-bound as a solid phase), alpha-tert-butyl-4-chloro-4’-methylbenzhydrol, cy- clohexyldiphenylmethanol, alpha-(p-tolyl)-benzhydrol, 1,1,2-triphenylethanol, alpha,alpha-diphe- nyl-2-pyridineethanol, alpha,alpha-4-pyridylbenzhydrol N-oxide, 2-fluorotriphenylmethanol, tri- phenylpropargyl alcohol, 4-[(diphenyl)hydroxymethyl]benzonitrile, 1-(2,6-dimethoxyphenyl)-2- methyl-1-phenyl-1-propanol, 1,1,2-triphenylpropan-1-ol and p-anisaldehyde carbinol. Organic halogen compounds which have one halogen atom in the molecule and are suitable as monofunctional initiators are in particular compounds of the general formula R¹³-Hal in which Hal is a halogen atom selected from fluorine, iodine and especially chlorine and bromine, and R¹³ denotes C₁- to C₂₀-alkyl radicals, especially C₁- to C₈-alkyl radicals, C₅- to C₈-cycloalkyl radi- cals or C - to C 13 7 20-arylalkyl radicals, especially C7- to C12-arylalkyl radicals. In addition, the R radicals may also comprise mixtures of the abovementioned structures and/or have other func- tional groups than those already mentioned, for example a keto function, a nitroxide or a car- boxyl group, and/or heterocyclic structural elements. Typical examples of such monohalogen compounds are methyl chloride, methyl bromide, ethyl chloride, ethyl bromide, 1-chloropropane, 1-bromopropane, 2-chloropropane, 2-bromopropane, 1-chlorobutane, 1-bromobutane, sec-butyl chloride, sec-butyl bromide, isobutyl chloride, isobutyl bromide, tert-butyl chloride, tert-butyl bromide, 1-chloropentane, 1-bromopentane, 1-chloro-hex- ane, 1-bromohexane, 1-chloroheptane, 1-bromoheptane, 1-chlorooctane, 1-bromooctane, 1- chloro-2-ethylhexane, 1-bromo-2-ethylhexane, cyclohexyl chloride, cyclohexyl bromide, benzyl chloride, benzyl bromide, 1-phenyl-1-chloroethane, 1-phenyl-1-bromoethane, 1-phenyl-2-chloro- ethane, 1-phenyl-2-bromoethane, 1-phenyl-1-chloropropane, 1-phenyl-1-bromopropane, 1-phe- nyl-2-chloropropane, 1-phenyl-2-bromopropane, 2-phenyl-2-chloropropane, 2-phenyl-2-bromo- propane, 1-phenyl-3-chloropropane, 1-phenyl-3-bromopropane, 1-phenyl-1-chlorobutane, 1- phenyl-1-bromobutane, 1-phenyl-2-chlorobutane, 1-phenyl-2-bromobutane, 1-phenyl-3-chloro- butane, 1-phenyl-3-bromobutane, 1-phenyl-4-chlorobutane, 1-phenyl-4-bromobutane, 2-phenyl- 1-chlorobutane, 2-phenyl-1-bromobutane, 2-phenyl-2-chlorobutane, 2-phenyl-2-bromobutane, 2-phenyl-3-chlorobutane, 2-phenyl-3-bromobutane, 2-phenyl-4-chlorobutane and 2-phenyl-4- bromobutane. The initiator is more preferably selected from organic hydroxyl compounds in which hydroxyl groups are bonded to an sp³-hybridized carbon atom, organic halogen compounds, in which halogen atoms are bonded to an sp³-hybridized carbon atom, and water. Among these, preference is given in particular to an initiator selected from organic hydroxyl compounds in which hydroxyl groups are bonded to an sp³-hybridized carbon atom. In the case of the organic halogen compounds as initiators, particular preference is further given to those in which the halogen atoms are bonded to a secondary or especially to a tertiary sp³- hybridized carbon atom. Preference is given in particular to initiators which may bear, on such an sp³-hydridized carbon atom, in addition to the hydroxyl group, the R¹², R¹³ and R¹⁴ radicals, which are each inde- pendently hydrogen, C1- to C20-alkyl, C5- to C8-cycloalkyl, C6- to C20-aryl, C7- to C20-alkylaryl or phenyl, where any aromatic ring may also bear one or more, preferably one or two, C₁- to C₄- alkyl, C₁- to C₄-alkoxy, C₁- to C₄-hydroxyalkyl or C₁- to C₄-haloalkyl radicals as substituents, where not more than one of the variables R¹², R¹³ and R¹⁴ is hydrogen and at least one of the variables R¹², R¹³ and R¹⁴ is phenyl which may also bear one or more, preferably one or two, C1- to C4-alkyl, C1- to C4-alkoxy, C1- to C4-hydroxyalkyl or C1- to C4-haloalkyl radicals as substit- uents. For the present invention, very particular preference is given to initiators selected from water, methanol, ethanol, 1-phenylethanol, 1-(p-methoxyphenyl)ethanol, n-propanol, isopropanol, 2- phenyl-2-propanol (cumene), n-butanol, isobutanol, sec.-butanol, tert-butanol, 1-phenyl-1-chlo- roethane, 2-phenyl-2-chloropropane (cumyl chloride), tert-butyl chloride and 1,3- or 1,4-bis(1- hydroxy-1-methylethyl)benzene. Among these, preference is given in particular to initiators se- lected from water, methanol, ethanol, 1-phenylethanol, 1-(p-methoxyphenyl)ethanol, n-propanol, isopropanol, 2-phenyl-2-propanol (cumene), n-butanol, isobutanol, sec.-butanol, tert-butanol, 1-phenyl-1-chloroethane and 1,3- or 1,4-bis(1-hydroxy-1-methylethyl)benzene. Preferred initiators bearing more than one functional group (fIn > 1) are tert-alkyl halides or ben- zyl or allyl halides or the substituted cycloalkanes described in US 7288614 B2, more preferably tert-alkyl halides and benzyl halides, even more preferably tert-alkyl and benzyl chlorides and bromides, and especially benzyl chlorides. Examples for tert-alkyl halides are 1,8-dichloro-4-p-menthane (limonene dihydrochloride), 1,8- dibromo-4-p-menthane (limonene dihydrobromide), 1 -(1-chloroethyl)-3-chlorocyclohexan, 1 -(1- chloroethyl-4-chlorocyclohexane, 1-(1-bromoethyl)-3-bromocyclohexane and 1-(1-bromoethyl)- 4-bromocyclohexane. Examples for benzyl halides are 1,4-bis (2-chloroprop-2-yl)benzene (dicumyl chloride). Examples for allyl halides are 2,5-dichloro-2,5-dimethylhex-3-ene. Examples for substituted cycloalkane halides are 1,5-dichloro-1,5-dimethylcyclooctane and 1,4- dichloro-1,4-dimethylcyclooctane. Among these examples dicumyl chloride, limonene dihydrochloride, and limonene dihydrobro- mide are preferred, more preferably dicumyl chloride and limonene dihydrochloride, and even more preferably dicumyl chloride. For the reaction according to the invention the ratio of iron halide : initiator is at least 0.5 : 1 to 10 : 1, preferably 1.1 : 1 to 8 : 1, more preferably 1.2 : 1 to 6 : 1. For the use of isobutene or of an isobutene-comprising monomer mixture as the monomer to be polymerized, suitable isobutene sources are both pure isobutene and isobutenic C₄ hydrocar- bon streams, for example C4 raffinates, especially "raffinate 1", C4 cuts from isobutane dehydro- genation, C4 cuts from steam crackers and from FCC crackers (fluid catalyzed cracking), pro- vided that they have been substantially freed of 1,3-butadiene present therein. A C4 hydrocar- bon stream from an FCC refinery unit is also known as "b/b" stream. Further suitable isobutenic C4 hydrocarbon streams are, for example, the product stream of a propylene-isobutane cooxida- tion or the product stream from a metathesis unit, which are generally used after customary pu- rification and/or concentration. Suitable C4 hydrocarbon streams generally comprise less than 500 ppm, preferably less than 200 ppm, of butadiene. The presence of 1-butene and of cis- and trans-2-butene is substantially uncritical. Typically, the isobutene concentration in the C4 hydro- carbon streams mentioned is in the range from 40 to 60% by weight. For instance, raffinate 1 generally consists essentially of 30 to 50% by weight of isobutene, 10 to 50% by weight of 1-bu- tene, 10 to 40% by weight of cis- and trans-2-butene, and 2 to 35% by weight of butanes; in the polymerization process according to the invention, the unbranched butenes in the raffinate 1 generally behave virtually inertly, and only the isobutene is polymerized. In a preferred embodiment, the monomer source used for the polymerization is a technical C4 hydrocarbon stream with an isobutene content of 1 to 100% by weight, especially of 1 to 99% by weight, in particular of 1 to 90% by weight, more preferably of 30 to 60% by weight, especially a raffinate 1 stream, a b/b stream from an FCC refinery unit, a product stream from a propylene-isobutane cooxidation or a product stream from a metathesis unit. Especially when a raffinate 1 stream is used as the isobutene source, the use of water as the sole initiator or as a further initiator has been found to be useful, in particular when polymeriza- tion is effected at temperatures of -20°C to +30°C, especially of 0°C to +20°C. At temperatures of -20°C to +30°C, especially of 0°C to +20°C, when a raffinate 1 stream is used as the isobu- tene source, it is, however, also possible to dispense with the use of an initiator. The isobutenic monomer mixture mentioned may comprise small amounts of contaminants such as water, carboxylic acids or mineral acids, without there being any critical yield or selectivity losses. It is appropriate to prevent enrichment of these impurities by removing such harmful substances from the isobutenic monomer mixture, for example by adsorption on solid adsor- bents such as activated carbon, molecular sieves or ion exchangers. It is also possible to convert monomer mixtures of isobutene or of the isobutenic hydrocarbon mixture with olefinically unsaturated monomers copolymerizable with isobutene. When mono- mer mixtures of isobutene are to be copolymerized with suitable comonomers, the monomer mixture preferably comprises at least 5% by weight, more preferably at least 10% by weight and especially at least 20% by weight of isobutene, and preferably at most 95% by weight, more preferably at most 90% by weight and especially at most 80% by weight of comonomers. Useful copolymerizable monomers include: vinylaromatics such as styrene and ^-methylsty- rene, C₁- to C₄-alkylstyrenes such as 2-, 3- and 4-methylstyrene, and 4-tert-butylstyrene, halo- styrenes such as 2-, 3- or 4-chlorostyrene, and isoolefins having 5 to 10 carbon atoms, such as 2-methylbutene-1, 2-methylpentene-1, 2-methylhexene-1, 2-ethylpentene-1, 2-ethylhexene-1 and 2-propylheptene-1. Further useful comonomers include olefins which have a silyl group, such as 1-trimethoxysilylethene, 1-(trimethoxysilyl)propene, 1-(trimethoxysilyl)-2-methylpro- pene-2, 1-[tri(methoxyethoxy)silyl]ethene, 1-[tri(methoxyethoxy)silyl]propene, and 1-[tri(methox- yethoxy)silyl]-2-methylpropene-2. In addition - depending on the polymerization conditions – useful comonomers also include isoprene, 1-butene and cis- and trans-2-butene. When the process according to the invention is to be used to prepare copolymers, the process can be configured so as to preferentially form random polymers or to preferentially form block copolymers. To prepare block copolymers, for example, the different monomers can be supplied successively to the polymerization reaction, in which case the second comonomer is especially not added until the first comonomer is already at least partly polymerized. In this manner, di- block, triblock and higher block copolymers are obtainable, which, according to the sequence of monomer addition, have a block of one or the other comonomer as a terminal block. In some cases, however, block copolymers also form when all comonomers are supplied to the polymerization reaction simultaneously, but one of them polymerizes significantly more rapidly than the other(s). This is the case especially when isobutene and a vinylaromatic compound, especially styrene, are copolymerized in the process according to the invention. This preferably forms block copolymers with a terminal polystyrene block. This is attributable to the fact that the vinylaromatic compound, especially styrene, polymerizes significantly more slowly than isobu- tene. The polymerization can be effected either continuously or batchwise. Continuous processes can be performed in analogy to known prior art processes for continuous polymerization of isobu- tene in the presence of boron trifluoride-based catalysts in the liquid phase. The process according to the invention is suitable either for performance at low temperatures, e.g. at -90°C to 0°C, or at higher temperatures, i.e. at at least 0°C, e.g. at 0°C to +30°C or at 0°C to +50°C. The polymerization in the process according to the invention is, however, prefera- bly performed at relatively low temperatures, generally at -70°C to -10°C, especially at -60°C to -15°C. In a preferred embodiment the polymerisation of the reaction mixture takes place at a tempera- ture of -60 °C or lower, e.g. from -60 to -90 °C. When the polymerization in the process according to the invention is effected at or above the boiling temperature of the monomer or monomer mixture to be polymerized, it is preferably per- formed in pressure vessels, for example in autoclaves or in pressure reactors. The polymerization in the process according to the invention is preferably performed in the pres- ence of an inert diluent. The inert diluent used should be suitable for reducing the increase in the viscosity of the reaction solution which generally occurs during the polymerization reaction to such an extent that the removal of the heat of reaction which evolves can be ensured. Suita- ble diluents are those solvents or solvent mixtures which are inert toward the reagents used. Suitable diluents are, for example, aliphatic hydrocarbons such as n-butane, n-pentane, n-hex- ane, n-heptane, n-octane and isooctane, cycloaliphatic hydrocarbons such as cyclopentane and cyclohexane, aromatic hydrocarbons such as benzene, toluene and the xylenes, and halogen- ated hydrocarbons, especially halogenated aliphatic hydrocarbons, such as methyl chloride, di- chloromethane and trichloromethane (chloroform), 1,1-dichloroethane, 1,2-dichloroethane, tri- chloroethane and 1-chlorobutane, and also halogenated aromatic hydrocarbons and alkylaro- matics halogenated in the alkyl side chains, such as chlorobenzene, monofluoromethylbenzene, difluoromethylbenzene and trifluoromethylbenzene, and mixtures of the aforementioned dilu- ents. The diluents used, or the constituents used in the solvent mixtures mentioned, are also the inert components of isobutenic C₄ hydrocarbon streams. A non-halogenated solvent is preferred over the list of halogenated solvents. The inventive polymerization may be performed in a halogenated hydrocarbon, especially in a halogenated aliphatic hydrocarbon, or in a mixture of halogenated hydrocarbons, especially of halogenated aliphatic hydrocarbons, or in a mixture of at least one halogenated hydrocarbon, especially a halogenated aliphatic hydrocarbon, and at least one aliphatic, cycloaliphatic or aro- matic hydrocarbon as an inert diluent, for example a mixture of dichloromethane and n-hexane, typically in a volume ratio of 10:90 to 90:10, especially of 50:50 to 85:15. Prior to use, the dilu- ents are preferably freed of impurities such as water, carboxylic acids or mineral acids, for ex- ample by adsorption on solid adsorbents such as activated carbon, molecular sieves or ion ex- changers. In a preferred embodiment, the inventive polymerization is performed in halogen-free aliphatic or especially halogen-free aromatic hydrocarbons, especially toluene. For this embodiment, wa- ter in combination with the organic hydroxyl compounds mentioned and/or the organic halogen compounds mentioned, or especially as the sole initiator, have been found to be particularly ad- vantageous. The polymerization in the process according to the invention is preferably performed under sub- stantially aprotic and especially under substantially anhydrous reaction conditions. Substantially aprotic and substantially anhydrous reaction conditions are understood to mean that, respec- tively, the content of protic impurities and the water content in the reaction mixture are less than 50 ppm and especially less than 5 ppm. In general, the feedstocks will therefore be dried before use by physical and/or chemical measures. More particularly, it has been found to be useful to admix the aliphatic or cycloaliphatic hydrocarbons used as solvents, after customary prepurifica- tion and predrying with an organometallic compound, for example an organolithium, organo- magnesium or organoaluminum compound, in an amount which is sufficient to substantially re- move the water traces from the solvent. The solvent thus treated is then preferably condensed directly into the reaction vessel. It is also possible to proceed in a similar manner with the mono- mers to be polymerized, especially with isobutene or with the isobutenic mixtures. Drying with other customary desiccants such as molecular sieves or predried oxides such as aluminum ox- ide, silicon dioxide, calcium oxide or barium oxide is also suitable. The halogenated solvents for which drying with metals such as sodium or potassium or with metal alkyls is not an option are freed of water or water traces with desiccants suitable for that purpose, for example with cal- cium chloride, phosphorus pentoxide or molecular sieves. It is also possible in an analogous manner to dry those feedstocks for which treatment with metal alkyls is likewise not an option, for example vinylaromatic compounds. The polymerization of the isobutene or of the isobutenic starting material generally proceeds spontaneously when the Lewis Acid-donor complex is contacted with the isobutene or the iso- butenic monomer mixture at the desired reaction temperature. The procedure here may be to initially charge the monomers, optionally in the diluent, to bring it to reaction temperature and then to add the Lewis Acid-donor complex. The procedure may also be to initially charge the Lewis Acid-donor complex, optionally in the diluent, and then to add the monomers. In that case, the start of polymerization is considered to be that time at which all reactants are present in the reaction vessel. To prepare isobutene copolymers, the procedure may be to initially charge the monomers, op- tionally in the diluent, and then to add the Lewis Acid-donor complex. The reaction temperature can be established before or after the addition of Lewis Acid-donor complex. The procedure may also be first to initially charge only one of the monomers, optionally in the diluent, then to add the Lewis Acid-donor complex, and to add the further monomer(s) only after a certain time, for example when at least 60%, at least 80% or at least 90% of the monomer has been con- verted. Alternatively, the Lewis Acid-donor complex, can be initially charged, optionally in the diluent, then the monomers can be added simultaneously or successively, and then the desired reaction temperature can be established. In that case, the start of polymerization is considered to be that time at which the Lewis Acid-donor complex, and at least one of the monomers are present in the reaction vessel. In addition to the batchwise procedure described here, the polymerization in the process ac- cording to the invention can also be configured as a continuous process. In this case, the feed- stocks, i.e. the monomer(s) to be polymerized, optionally the diluent and optionally the Lewis Acid-donor complex are supplied continuously to the polymerization reaction, and reaction prod- uct is withdrawn continuously, such that more or less steady-state polymerization conditions are established in the reactor. The monomer(s) to be polymerized can be supplied as such, diluted with a diluent or solvent, or as a monomer-containing hydrocarbon stream. The Lewis Acid-donor complex effective as a polymerization catalyst is generally present in dis- solved, dispersed or suspended form in the polymerization medium. Supporting of the Lewis Acid-donor complex on customary support materials is also possible. Suitable reactor types for the polymerization process of the present invention are typically stirred tank reactors, loop reac- tors and tubular reactors, but also fluidized bed reactors, stirred tank reactors with or without solvent, fluid bed reactors, continuous fixed bed reactors and batchwise fixed bed reactors (batchwise mode). In the process according to the invention, the Lewis Acid-donor complex, is generally used in such an amount that the molar ratio of iron atoms in the Lewis Acid-donor complex to isobutene in the case of homopolymerization of isobutene, or to the total amount of the polymerizable monomers used in the case of copolymerization of isobutene, is in the range from 1:5 to 1:5000, preferably from 1:10 to 1:5000, especially 1:15 to 1:1000, in particular 1:20 to 1:250. To stop the reaction, the reaction mixture is preferably deactivated, for example by adding a protic compound, especially by adding water, alcohols such as methanol, ethanol, n-propanol and isopropanol or mixtures thereof with water, or by adding an aqueous base, for example an aqueous solution of an alkali metal or alkaline earth metal hydroxide such as sodium hydroxide, potassium hydroxide, magnesium hydroxide or calcium hydroxide, an alkali metal or alkaline earth metal carbonate such as sodium, potassium, magnesium or calcium carbonate, or an al- kali metal or alkaline earth metal hydrogencarbonate such as sodium, potassium, magnesium or calcium hydrogencarbonate. The process according to the invention serves to prepare high-reactivity isobutene homo- or co- polymers with a content of terminal functional groups (see below) which are or can easily be converted into vinylidene double bonds ( ^-double bonds) per polyisobutene chain end of at least 70, preferably at least 75 and very preferably at least 80 mol%, preferably of at least 85 mol%, more preferably of at least 90 mol%, more preferably of more than 91 mol% and es- pecially of at least 95 mol%, for example of virtually 100 mol%. More particularly, it also serves to prepare high-reactivity isobutene copolymers which are formed from isobutene and at least one vinylaromatic monomer, especially styrene, and have a content of terminal functional groups, preferably vinylidene double bonds ( ^-double bonds) per polyisobutene chain end of at least 70, preferably at least 75 mol%, preferably of at least 80 mol%, preferably of at least 85 mol%, more preferably of at least 90 mol%, more preferably of more than 91 mol% and es- pecially of at least 95 mol%, for example of virtually 100 mol%. To prepare such copolymers of isobutene and at least one vinylaromatic monomer, especially styrene, isobutene or an isobu- tenic hydrocarbon cut is copolymerized with the at least one vinylaromatic monomer in a weight ratio of isobutene to vinylaromatic of 5:95 to 95:5, especially of 30:70 to 70:30. It is an advantage of the present invention that the reaction yields polymers with a polydispersity PDI of not more than 2.0. The isobutene homo- or copolymers prepared by the process according to the invention and specifically the isobutene homopolymers preferably have a polydispersity (PDI = M_w/M_n) of from 1.0 to 2.0, preferably of 1.05 to less than 2.0, preferably of 1.05 to 1.9, preferably of 1.05 to 1.85, more preferably of 1.05 to 1.80 and especially of 1.1 to 1.7. Typical PDI values in the case of an optimal process regime are 1.1 to 1.6. The high-reactivity isobutene homo- or copolymers prepared by the process according to the invention preferably possess a number-average molecular weight M_n (determined by gel perme- ation chromatography) of preferably 500 to 250000, more preferably of 500 to 100000, even more preferably of 500 to 25000, most preferably of from 750 to 23000 g/mol, especially 1000 to 20000 g/mol. Isobutene homopolymers even more preferably possess a number-aver- age molecular weight Mn of 500 to 10000 and especially of 500 to 5000, for example of about 1000 or of about 2300. The functionality of the polyisobutene f_PIB refers to the sum of reactive double bonds and halide- groups terminating the polymer chains. The reactive double bonds may be both double bonds in the last bond in the polymer chain -C(CH3)=CH2, also referred to as alpha- or exo-double bond, or in the second last bond -CH=C(CH3)2, also referred to as beta- or endo-double bond. The halide groups may originate from the halide of the iron halide or from the initiator employed and, therefore, is the same as the halides used there, preferably chloride. The functionality of the polyisobutene fPIB does not exceed the functionality of the initiator fIn but ideally is equal to fIn. In practice fPIB is from 0.3 to 1 × fIn, preferably from 0.4 to 0.99 × fIn, more preferably from 0.5 to 0.98 × fIn, and most preferably from 0.6 to 0.95 × fIn. The process according to the invention successfully polymerizes isobutene or isobutene-com- prising monomer mixtures under cationic conditions with satisfactory to high conversions of gen- erally 20 to 100%, especially 35 to 90%, in short reaction times of generally 5 to 120 minutes, especially 30 to 120 minutes, to give isobutene homo- or copolymers with a functionality fPIB of one or preferably more than 1 and a content of terminal functional groups per polyisobutene chain end of at least 70, preferably at least 75 and very preferably at least 80 mol% and with a narrow molecular weight distribution. According to the present invention the complex of iron halide and at least one donor compound is being formed complex in the absence of a isobutene-containing monomer feedstock. For the formation of the complex iron halide and the at least one donor compound are brought together in a molar ratio of from 1 : 1.1 to 1 : 1.9, preferably in a molar ratio of from 1 : 1.2 to 1 : 1.8, more preferably of from 1 : 1.2 to 1 : 1.7, even more preferably 1 : 1.3 to 1 : 1.7, most preferably 1 : 1.3 to 1 : 1.6, and especially 1 : 1.4 to 1 : 1.5. After the formation the complex is brought into contact with the isobutene-containing monomer feedstock. The formation of the complex may occur in the presence of at least one of the above-mentioned solvents or inert diluents, preferably in the presence of at least one of the above-mentioned sol- vents or inert diluents, even more preferably in the presence of at least one of the above-men- tioned non-halogenated solvents or inert diluents In a preferred embodiment the temperature during formation and storage of the complex is kept at at most 10 °C, more preferably at most 5 °C, and even more preferably at most 0 °C. The maximum temperature during storage also depends on the solvent in which the complex is pre- pared: A complex prepared in methylene chloride should be kept at a maximum temperature of 0 °C while a complex prepared in hydrocarbons, preferably aromatic hydrocarbons, and very preferably toluene can be stored at a temperature up to room temperature. It has been shown that the thus formed and stored complexes exhibit a higher reactivity, especially at short reac- tion time. On the other hand, an increased temperature during formation and/or storage of the complex may lead to a higher functionality of the polyisobutene although the reactivity is lower. For that purpose, the temperature during formation and/or storage of the complex may exceed 10 °C but should not raise above 30 °C, preferably not more than 25 °C, even more preferably not more than 20 °C. It is an advantage of the present invention that the complexes according to the invention are less sensitive towards water, e.g. in the form of moisture, than other Lewis Acids, especially tita- nium chloride TiCl4. The complex according to the present invention may tolerate up to 60 mol% of water with regard to FeX3, preferably up to 50, more preferably up to 40, and even more pref- erably up to 30 mol% of water. In contrast, the activity of the complex can be significantly increased by the addition of 10 to 20 mol% of water which, therefore, is a preferred embodiment. Reactivity and polydispersity of the complexes according to the invention deteriorates only slightly but remains acceptable compared with conducting the reaction in a water-free manner. Still preferably the amount of water does not exceed 10 mol% with regard to FeX₃, more prefer- ably not more than 5 mol%, even more preferably not more than 2 mol%, especially not more than 1 mol%. In a preferred embodiment the formation and storage of the complex as well as the reaction is carried out under water-free conditions. In one embodiment of the reaction according to the invention the polymerisation is quenched with an ether compound R³-O-R⁴, wherein R³ and R⁴ independently of another represent are an organic residue of up to 20 carbon atoms, preferably C1- to C20-alkyl, C5- to C8-cycloalkyl radi- cal, C6- to C20-aryl radical or C7- to C20-arylalkyl radical, or together with the oxygen atom may form a five-, six- or seven-membered ring, at a temperature of -60 °C or lower. Ethers may be the same as or different from those ethers listed above as compounds R¹-O-R². It is an advantage of this embodiment that on treatment with the ether R³-O-R⁴ the halide-con- taining end groups of the polymerisation are mostly converted into alpha- or beta-double bonds as end groups rather than halide end groups. For quenching the ether compound R³-O-R⁴ is used in a molar ratio of at least 5 : 1 with regard to the initiator, preferably at least 7 : 1, more preferably at least 9 : 1, and especially 10 : 1. Usu- ally the molar ratio should not exceed a molar ratio of 50 : 1, preferably not more than 30 : 1, and more preferably not more than 20 : 1. Higher amounts of ether compound may be advanta- geous if the ether is used as a work up-procedure for purification of the polyisobutene. It is an advantage of the polymerisation of the present invention that the polymer chain ends may undergo further reaction, e.g. with phenols. The further reaction is carried out in the presence of at least one Lewis acid different from the iron halide employed in the polymerisation, preferably selected from the group consisting of alu- minium halides, alkyl aluminium halides, boron halides, titanium halides or zirconium halides, preferably the chlorides or in the case of boron preferably boron fluoride. The phenol is used in molar amounts of at least the functionality fIn of the initiator, preferably at least 1.1 × fIn, more preferably at least 1.2 × fIn, even more preferably at least 1.3 × fIn, and es- pecially at least 1.5 × fIn. Higher amounts of phenol up to 10 × fIn, preferably up to 20 × fIn or even up to 25 × f_In usually lead to higher conversion of the polymer chains. Usually, the phenol and the Lewis acid different from the iron halide are mixed together in a sol- vent and the solution added to the polymerisation mixture at the temperature of polymerisation and the reaction mixture is gradually warmed up to room temperature or even up to 60 °C. The reaction time may be from 0.5 to 10 hours, preferably from 1 to 5 hours. The phenols used may be substituted or preferably unsubstituted. In case substituted phenols are employed, preferably the para position should be unsubstituted. Hence, an example for such a phenol is o-cresol. It is an advantage of the thus obtained reaction product that the polymer bears a phenolic group as end group and the phenolic hydroxy group is available for further derivatives, e.g. reaction with epoxides or transesterification with esters, e.g. (meth)acrylic acid esters so that further functional groups maybe introduced into the polymer. Further to phenols the polymer chain ends may also be reacted with alkoxyaromates, wherein the alkoxy group may bear further functional groups. Such alkoxyaromates may be the above-mentioned phenols bearing optionally substituted alkyl groups at the phenolic OH-group. Unsubstituted alkyl-groups may be C1- to C20-, preferably C1- to C10-, and more preferably C1- to C4-alkyl groups, especially methyl, iso-propyl or tert.-butyl. Such alkyl groups may be one- or multifold, preferably onefold substituted with hydroxy- (-OH), amino- (-NH2) or halide-groups, preferably hydroxy-, chloro- or bromo-groups, very preferably hydroxy-groups. Preferred examples for substituted alkyl groups are 2-hydroxyethyl, 2-chloroethyl, 2-bromoethyl, 3-hydroxypropyl, 3-aminopropyl, 3-chloropropyl, 3-bromopropyl, 4-hydroxybutyl, 4-chlorobutyl, and 4-bromobutyl. The reaction conditions of the reaction of the polymer chain ends with alkoxyaromates are com- parable to those of phenols mentioned above. Examples of such a reaction of the polymer chain ends, although obtained from TiCl₄-catalysed polymerisation reaction, is described in David L. Morgan, Nemesio Martinez-Castro, and Rob- son F. Storey, Macromolecules 2010, 43, 8724–8740. Examples Materials.1,4-Bis(2-hydroxyisopropyl)benzene (dicumyl alcohol, 97%, Sigma–Aldrich), FeCl₃ (97%, Fisher), ethanol (99.5%, Sigma–Aldrich), phenol (PhOH, ≥99%, Sigma–Aldrich), tetrahy- drofuran (THF, Sigma–Aldrich, >99.9 for HPLC), CaH2 (93%, Acros Organics), SnCl2 ^H2O (98%, Sigma–Aldrich) were used as received. ⁱPrOH (iso propanol, 99.5%, Sigma–Aldrich) was refluxed and then distilled over SnCl₂ ^H₂O under argon atmosphere (98%, Sigma–Aldrich) and stored under 4 Å molecular sieves. 2,6-Dimethylpiridine (2,6-lutidine, 98%, Sigma–Aldrich) was dried under CaH2 and distilled from CaH2 under reduced pressure. TiCl4 (Aldrich, ≥99%) was distilled with copper chips under reduced pressure. Isobutylene (IB, 99%, Sigma–Aldrich) was dried in the gaseous state by passing through La- boratory Gas Drying Unit (Stock #26800), condensed at –40 ºC, and stored under molecular sieves. Dichloromethane (>99.5%, Sigma–Aldrich), n-hexane (>95%, Sigma–Aldrich) were treated with sulphuric acid, washed with aqueous sodium bicarbonate, dried over CaCl2, and dis- tilled twice over CaH₂ under an inert atmosphere and stored under 4 Å molecular sieves. Diiso- propyl ether (ⁱPr2O) (99%, Sigma–Aldrich), 1-butanol (BuOH) (99%, Sigma–Aldrich), dibutyl ether (Bu2O) (99,3%, Sigma–Aldrich), bis(2-chloroethyl) ether (CEE, 99%, Sigma–Aldrich) were re- fluxed under CaH2 and distilled over CaH2 under an inert atmosphere (BuOH, ⁱPr2O) or vacuum (Bu₂O, CEE) and stored under 4 Å molecular sieves. Characterization. Size exclusion chromatography was performed on an Ultimate 3000 device with PLgel MIXED-C column (7.5×300 mm, particle size 5 μm) and one pre-column (Agilent PLgel 5 μm guard) thermostated at 30 °C, equipped with a differential refractometer. Solutions of the polymers in THF were eluted at flow rate of 1 mL/min. The calculation of molecular weight and polydispersity was based on polystyrene standards (Polymer Labs) with PDI≤ 1.05 and using Chromeleon 7.0 program. ¹H NMR (500 MHz) spectra were recorded in CDCl₃ at 25 ℃ on a Bruker AC-500 spectrometer calibrated relative to the residual solvent resonance. Synthesis of 1,4-bis(2-chloropropan-2-yl)benzene (dicumyl chloride, DiCumCl). Dicumyl chloride (DiCumCl) was prepared via passing gaseous HCl through a solution of 2 g of 1,4-bis(2- hydroxyisopropyl)benzene (dicumyl alcohol) in 30 mL of CH₂Cl₂ at 0 ºC under stirring. Then, ex- cess of HCl was removed from solution by babbling of dry argon, the solvent was evaporated and the initiator was twice recrystallized from n-hexane and dried in vacuum at room temperature. Purity of the prepared dicumyl chloride was confirmed by ¹H NMR spectroscopy. Synthesis of complexes of FeCl₃. Complexes of FeCl₃ with alcohols or ethers were prepared under argon atmosphere in CH₂Cl₂ at 0 °C. Firstly, FeCl₃ was air-tightly transferred into flask and weighted; then required amount of CH₂Cl₂ was added via a volumetric pipette. After that, the required amount of alcohol or ether was added dropwise to slurry of FeCl₃ in CH₂Cl₂ under vigor- ous stirring. As an example of a typical procedure, the synthesis of FeCl₃×1.4ⁱPrOH (0.22 M) was given bellow: ⁱPrOH (0.198 ml, 2.59 mmol) was added dropwise to slurry of FeCl₃ (0.3 g, 1.85 mmol) in 8.2 ml of CH₂Cl₂. Polymerization. The polymerization reaction was carried out in glass tubes under argon at- mosphere at –80 °C. As an example of the typical procedure, polymerization was initiated by addition of solution of FeCl3×1.4 ⁱPrOH in CH2Cl2 (1 mL, 0.22M) to a mixture of total volume 11 mL consisting of dicumyl chloride (0.025g, 0.11 mmol), isobutylene (1.2 mL, 14.52 mmol), n-hex- ane (6.5 mL) and CH2Cl2 (3.3 mL). After a predetermined time (1-2 min), the polymerization was terminated by 2 mL of ethanol with 0.5% of NaOH. The quenched reaction mixture diluted by n- hexane, centrifuged to remove the iron–containing residues, evaporated to dryness under re- duced pressure, and dried in vacuum at 40 °C to give the product polymers. Monomer conver- sions were determined gravimetrically. The content of chlorine (PIBCl), exo-olefin and olefin end groups as well as the difunctional inititator in the polymer chain (Fn( ^)) were calculated from ¹H NMR spectrum of synthesized pol- yisobutylene (Figure 1): chlorine end groups (mol%) = [∫(h)6] / [∫(h)/6+∫(i)+ ∫(j)/2)] (1) exo-olefin end groups (mol%) = [∫(i)] / [∫(h)/6+∫(i)+ ∫(j)/2)] (2) olefin end groups (mol%) = [∫(i)+ ∫(j)/2)] / [∫(h)/6+∫(i)+ ∫(j)/2)] (3) Fn( α) = [∫(d)/12] / [∫(d)/12+∫(CH3- head group of monofunctional IB at 0.99 ppm)/6] ⁽⁴⁾

Table 1. Effect of Catalyst Preparation on the Cationic Polymerization of IB with Di- CumCl/FeCl₃ ^1.4ⁱPrOH Initiating System^a d di t i

^a Conditions: [IB] = 1.2 M; [DiCumCl] = 9mM; CH2Cl2/n-hexane 40: 60 (v/v); [FeCl3 ^1.4iPrOH]=38 mM;. ^c Total olefinic end groups content including exo-, endo-olefin, tri-, tetra-substituted olefin end groups and coupled polymer chains determined by ¹H NMR spectroscopy (see Figure 1 for details). ^dFraction of difunctional PIB calculated from ¹H NMR spectroscopy. ^eSolutions of iPrOH and FeCl₃ were sequentially added into the reactor containing solvents, IB and initiator to initiate the polymerization (no complex was pre-formed). ^f polymerisation was initiated by the simultane- ous addition of isobutylene and solution of DiCumCl to the reactor containing FeCl₃, solvents and iPrOH (the complex was pre-formed in situ during 2-3 min just before monomer and initiator addition at -80 °C) Catalytic complex preparation: Complex I: FeCl3 ^1.4ⁱPrOH was prepared in CH2Cl2 (0.22 M) at 0 ^C and then heated to room temperature (20 ^C – 25 ^C) before use. Complex II: FeCl₃ ^1.4ⁱPrOH was prepared in CH₂Cl₂ (0.22 M) at 0 ^C and then stored and used at 0 ^C. Entries 1 and 2 for comparison show that separate introduction of neat FeCl3 is not sufficient to start the reaction. Entries 3 vs 4 and 5 vs 6 show that pre-forming the iron halide-catalyst with the donor at contin- uous low temperature (entries 4 and 6) is advantageous over higher temperatures. Table 2: Different Initiator and Co-initiator Concentrations ^a entr DiCumCl FeCl time conv M ^PDI _{F ( ^)}c end rou s

a Polymerization conditions: [IB] = 1.2 M; Temperature: – 80 ºC; CH₂Cl₂/n-hexane 40:60 v/v. c Fraction of difunctional PIB calculated from ¹H NMR spectroscopy. ^d Total olefinic end groups content including exo-, endo-olefin, tri-, tetra-substituted olefin end groups and coupled polymer chains determined by ¹H NMR spectroscopy (see Figure 1 for details). ^e No initiator was added. ^f FeCl₃ ^1.1ⁱPrOH was used as co-initiator instead of FeCl₃ ^1.4ⁱPrOH Table 3. Effect of Temperature on the Cationic Polymerization of Isobutylene with Di- CumCl/FeCl₃ X1.4ⁱPrOH Initiating System ^a

^a Conditions: [IB] = 1.2 M; [DiCumCl]=9mM; [FeCl3 ^1.4iPrOH]=19 mM; CH2Cl2/n-hexane 40:60 v/v; ^c Fraction of difunctional PIB calculated from ¹H NMR spectroscopy It can easily be seen that with increasing temperature conversion decreases and polydispersity increases. Table 4: Effect of H₂O on the Polymerization. The polymerization reaction was carried out in glass tubes under argon atmosphere at –80 °C. As an example of the typical procedure, polymer- ization was initiated by addition of solution of FeCl₃×1.4 ⁱPrOH in CH₂Cl₂ (1 mL, 0.22M) to a mix- ture of total volume 11 mL consisting of dicumyl chloride (0.025g, 0.11 mmol), isobutylene (1.2 mL, 14.52 mmol), n-hexane (6.5 mL) and CH₂Cl₂ (3.3 mL). After a predetermined time (1-2 min), the polymerization was terminated by 2 mL of ethanol with 0.5% of NaOH. The quenched reaction mixture diluted by n-hexane, centrifuged to remove the iron–containing residues, evaporated to dryness under reduced pressure, and dried in vacuum at 40 °C to give the product polymers. Monomer conversions were determined gravimetrically. The content of chlorine (PIBCl), exo-olefin and olefin end groups as well as the difunctional inititator in the polymer chain (F_n( ^)) were calculated from ¹H NMR spectrum of synthesized pol- yisobutylene (Figure 1): chlorine end groups (mol%) = [∫(h)6] / [∫(h)/6+∫(i)+ ∫(j)/2)] (1) exo-olefin end groups (mol%) = [∫(i)] / [∫(h)/6+∫(i)+ ∫(j)/2)] (2) olefin end groups (mol%) = [∫(i)+ ∫(j)/2)] / [∫(h)/6+∫(i)+ ∫(j)/2)] (3) F_n( ^) = [∫(d)/12] / [∫(d)/12+∫(CH₃- head group of monofunctional IB at 0.99 ppm)/6] ⁽⁴⁾ Cationic Polymerization of IB with DiCumCl/LA (LA=FeCl3 ^1.4ⁱPrOH or pure TiCl4) Initiating Sys- tem ^a entr [H₂O]/ LA time conv M ^PDI _{F ( ^)}c end rou s

a Polymerization conditions: [IB] = 1.2 M; [DiCumCl]=9 mM; [FeCl3 ^1.4ⁱPrOH]=[TiCl4]=14 mM. Temperature: –80 ºC; CH2Cl2/n-hexane 40:60 v/v. ^c Fraction of difunctional PIB calculated from ¹H NMR spectroscopy. ^d Total olefinic end groups content including exo-, endo-olefin, tri-, tetra- substituted olefin end groups and coupled polymer chains determined by ¹H NMR spectroscopy (see Figure 1 for details). ^e 2,6-Lutidine (5 mM) was added as a proton trap. It can easily be seen that FeCl3 as a catalyst is less sensitive towards water than TiCl4 for com- parative purposes, especially with regard to conversion and polydispersity. Table 5: One-Step Alkylation of Phenol by Living PIB Synthesized with DiCum/FeCl₃ ^1.4iPrOH Initiating System ^a r

Polymerization: T = –80 ºC; [IB]=1.2 M; [FeCl3 ^1.4ⁱPrOH]=18 mM; [DiCumCl] = 9 mM, CH2Cl2/hex 40:60 v/v; time: 2 min. Alkylation: solution of AlCl₃/PhOH in CH₂Cl₂ ([PhOH]=2.55 M; [AlCl₃] = 0.155 M) was added to the system, the alkylation conducted at room temperature. ^b Alkylation: solution of FeCl3/PhOH in CH2Cl2 ([PhOH]=2.55 M; [FeCl3] = 0.155 M) was added to the system. Table 6: Monofunctional polyisobutene using Cumylchlorid/FeCl₃ ^1.4ⁱPrOH as initiating system I M M /M E d di tib ti r

Conditions: [IB] = 1.2 M; [FeCl₃] = 18 mM; initiator I: cumyl chloride; T: - 80 ºC; CH₂Cl₂/n-hexane 40:60 v/v; ^a Fraction of PIB chains containing fragment of initiator calculated from ¹H NMR spec- troscopy Table 7: Monofunctional polyisobutene using TMPCl/FeCl3 ^1.4ⁱPrOH as initiating system (TMPCl: 2-chloro-2,4,4-trimethylpentane) M M /M E d di tib ti r

Conditions: [IB] = 1.2 M; T: - 70 ºC; [TMPCl]=134 mM; [FeCl3 ^1.4ⁱPrOH]=18 mM; CH2Cl2/n-hex- ane 40:60 v/v. ^aCH₂Cl₂ as a solvent. ^b [TMPCl]=67 mM

Claims

Claims 1. Process for manufacturing of polyisobutenes with a functionality f_PIB of one or preferably more than 1 and a M_n of from 500 to 25000 g/mol, comprising the steps of - providing an initiator In with a functionality f_In of one or preferably more than 1 - providing an isobutene-containing monomer feedstock - polymerising the reaction mixture of initiator In and isobutene-containing monomer feedstock in the presence of an iron halide FeX₃ , preferably iron chloride FeCl₃ catalyst and at least one donor compound R¹-O-R², wherein R¹ and R² independently of another represent are an organic residue of up to 20 carbon atoms, preferably C1- to C20-alkyl, C5- to C8-cycloalkyl radical, C6- to C20-aryl radical or C₇- to C₂₀-arylalkyl radical, or together with the oxygen atom may form a five-, six- or seven-membered ring, and R² additionally is hydrogen, X independently of another represents halide, characterised in that prior to the polymerisation iron halide and the at least one donor compound are brought together in a molar ratio of 1 : 1.1 to 1 : 1.9 forming a complex in the absence of a isobutene-containing monomer feedstock and the thus formed complex is brought into contact with the isobutene-containing monomer feedstock. 2. Process according to Claim 1, wherein the at least one donor compound R¹-O-R² is se- lected from the group consisting of dimethyl ether, diethyl ether, di-n-propyl ether, diiso- propyl ether, di-n-butyl ether, di-sec-butyl ether, diisobutyl ether, di-n-pentyl ether, di-n- hexyl ether, di-n-heptyl ether, di-n-octyl ether, di-(2-ethylhexyl) ether, methyl n-butyl ether, methyl sec-butyl ether, methyl isobutyl ether, methyl tert-butyl ether, ethyl n-butyl ether, ethyl sec-butyl ether, ethyl isobutyl ether, ethyl tert-butyl ether, n-propyl-n-butyl ether, n-propyl sec-butyl ether, n-propyl isobutyl ether, n-propyl tert-butyl ether, isopropyl n-butyl ether, isopropyl sec-butyl ether, isopropyl isobutyl ether, isopropyl tert-butyl ether, methyl n-hexyl ether, methyl n-octyl ether, methyl 2-ethylhexyl ether, ethyl n-hexyl ether, ethyl n-octyl ether, ethyl 2-ethylhexyl ether, n-butyl n-octyl ether, n-butyl 2- ethylhexyl ether, tetrahydrofuran, tetrahydropyran, 1,2-, 1,3- and 1,4-dioxane, dicyclo- hexyl ether, diphenyl ether, alkyl aryl ethers, such as anisole and phenetole, ditolyl ether, dixylyl ether, dibenzyl ether, bis (2-chloroethyl) ether, 2-chloroethyl ethyl ether,

2-chloro- ethyl methyl ether, chloromethyl methyl ether, and chloromethyl ethyl ether.

3. Process according to Claim 1, wherein the at least one donor compound R¹-O-R² is se- lected from the group consisting of diethyl ether, diisopropyl ether, di-n-butyl ether and diphenyl ether.

4. Process according to any one of the preceding claims, wherein the temperature during complex formation and storage does not exceed 10 °C.

5. Process according to Claim 4, wherein complex is prepared in methylene chloride and the temperature during complex formation and storage does not exceed 0 °C.

6. Process according to any of the Claims 1 to 3, wherein complex is prepared in hydrocar- bons, preferably aromatic hydrocarbons, and very preferably toluene and the tempera- ture during complex formation and storage does not exceed 30 °C.

7. Process according to any one of the preceding claims, wherein the ratio of iron halide : initiator is at least 0.5 : 1 to 10 : 1, preferably 1.1 : 1 to 8 : 1, more preferably 1.2 : 1 to 6 : 1.

8. Process according to any one of the preceding claims, wherein the amount of water is up to 60 mol% with regard to the iron halide, preferably up to 50, more preferably up to 40, and especially up to 30 mol%.

9. Process according to any one of the preceding claims, wherein the amount of water is 10 to 20 mol%.

10. Process according to any one of the preceding claims, wherein the polymerisation of the reaction mixture takes place at a temperature of -60 °C or lower.

11. Process according to any one of the preceding claims, wherein the polyisobutene exhib- its a number-average molecular weight Mn of from 500 to 25000 g/mol, preferably of from 750 to 23000 g/mol, more preferably 1000 to 20000 g/mol.

12. Process according to any one of the preceding claims, wherein the reaction mixture of the polymerisation is quenched with an ether compound R³-O-R⁴, wherein R³ and R⁴ in- dependently of another represent are an organic residue of up to 20 carbon atoms, pref- erably C1- to C20-alkyl, C5- to C8-cycloalkyl radical, C6- to C20-aryl radical or C7- to C20- arylalkyl radical, or together with the oxygen atom may form a five-, six- or seven- membered ring, at a temperature of -60 °C or lower.

13. Process according to Claim 12, wherein the ether compound R³-O-R⁴ during quenching is used in a molar ratio of at least 5 : 1 with regard to the initiator.

14. Process according to any one of the Claims 1 to 11, wherein the reaction mixture is fur- ther reacted with phenols or optionally substituted alkoxyaromates.

15. Process according to Claim 14, wherein in the reaction is carried out in the presence of at least one Lewis acid different from the iron halide employed in the polymerisation, preferably selected from the group consisting of aluminium halides, alkyl aluminium hal- ides, boron halides, titanium halides or zirconium halides.