PROCESS FOR PREPARING HIGH-REACTIVITY ISOBUTENE HOMO- OR COPOLYMERS

Abstract

The present invention relates to a novel process for preparing high-reactivity isobutene homo- or copolymers with a content of terminal vinylidene double bonds per polyisobutene chain end of at least 70 mol %. The present invention further relates to novel isobutene polymers.

Claims

1. A process for preparing high-reactivity isobutene homo- or copolymers with a content of terminal vinylidene double bonds per polyisobutene chain end of at least 70 mol %, the process comprising: polymerizing isobutene or an isobutene-comprising monomer mixture in the presence at least one Lewis Acid effective as a polymerization catalyst, selected from the group consisting an aluminum trihalide-donor complex, an alkylaluminum halide-donor complex, an iron trihalide-donor complex, a gallium trihalide-donor complex, a titanium tetrahalide-donor complex, a zinc dihalide-donor complex, a tin dihalide-donor complex, and a tin tetrahalide-donor complex, effective as a polymerization catalyst, said complex comprising, as the donor, a mixture of: at least organic compound (II) comprising at least one oxygen or nitrogen atom with at least one lone electron pair, preferably comprising at least one oxygen atom with at least one lone electron pair, very preferably selected from the group consisting of organic compounds with at least one ether function, organic compounds with at least one carboxylic ester function, organic compounds with at least one aldehyde function, organic compounds with at least one keto function, and organic compounds with at least one nitrogen containing heterocyclic ring, and at least one ionic liquid.

2. The process according to claim 1, wherein the ionic liquid comprises a cation selected from the group consisting of formulae (Ia) to (Iw); ##STR00009## ##STR00010## ##STR00011## and oligomers and polymers in which these structures are present, where R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6 and R.sup.7 are each, independently of one another, C.sub.1-C.sub.18-alkyl, C.sub.2-C.sub.18-alkyl interrupted by one or more oxygen and/or sulfur atoms and/or one or more substituted or unsubstituted imino groups, C.sub.6-C.sub.12-aryl, C.sub.5-C.sub.12-cycloalkyl or a five- or six-membered, oxygen-, nitrogen- and/or sulfur-containing heterocycle or two of them together form an unsaturated, saturated or aromatic ring which may be interrupted by one or more oxygen and/or sulfur atoms and/or one or more substituted or unsubstituted imino groups, where the radicals mentioned may each be substituted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halogen, heteroatoms and/or heterocycles.

3. The process according to claim 1, wherein the ionic liquid comprises an anion selected from the group consisting of fluoride, chloride; bromide, iodide; thiocyanate; hexafluorophosphate; trifluoromethanesulfonate; methanesulfonate; carboxylates; mandelate; nitrate; nitrite; trifluoroacetate; sulfate; hydrogensulfate; methylsulfate; ethylsulfate; 1-propylsulfate; 1-butylsulfate; 1-hexylsulfate; 1-octylsulfate; sulfite; hydrogensulfite; phosphate; dihydrogenphosphate; hydrogenphosphate; C.sub.1-C.sub.4-dialkylphosphates; carbonate C.sub.3.sup.2, hydrogencarbonate HCO.sub.3.sup.; propionate; tetrachloroaluminate; Al.sub.2Cl.sub.7.sup.; Al.sub.3Cl.sub.10.sup.; chlorozincate; chloroferrate; chlorocuprate CuCl.sub.2.sup., bis(trifluoromethylsulfonyl)imide, bis(pentafluoroethylsulfonyl)imide, bis(methylsulfonyl)imide; bis(p-tolylsulfonyl)imide; tris(trifluoromethylsulfonyl)methide; bis(pentafluoroethylsulfonyl)methide; p-tolylsulfonate; tetracarbonylcobaltate; dimethyleneglycolmonomethylethersulfate; oleate; stearate; acrylate; methacrylate; maleate; hydrogencitrate; vinylphosphonate; bis(pentafluoroethyl)phosphinate; borates; dicyanamide; tris(pentafluoroethyl)trifluorophosphate; tris(heptafluoropropyl)trifluorophosphate, cyclic arylphosphates such as pyrocatecholphosphate of the formula (C.sub.6H.sub.4O.sub.2)P(O)O; and chlorocobaltate.

4. The process according to claim 1, wherein the ionic liquid is an imidazolium salt of the general formula (I). ##STR00012## wherein: the variables R.sup.a and R.sup.c are each independently an organic radical having 1 to 3000 carbon atoms, the variables R.sup.b, R.sup.d and R.sup.e are each independently hydrogen or an organic radical having 1 to 3000 carbon atoms, X is an anion, and n is the number 1, 2 or 3.

5. The process according to claim 1, wherein isobutene or an isobutene-comprising monomer mixture is polymerized in the presence of an aluminum trihalide-donor complex, an alkylaluminum halide-donor complex, an iron trihalide-donor complex, a gallium trihalide-donor complex or a titanium tetrahalide-donor complex.

6. The process according to claim 1, wherein isobutene or an isobutene-comprising monomer mixture is polymerized in the presence of an aluminum trichloride-donor complex or an alkylaluminum halide-donor complex or an iron-trihalide donor complex effective as a polymerization catalyst.

7. The process according to claim 1, wherein the at least one organic compound (II) is selected from the group consisting of organic compounds with at least one ether function, organic compounds with at least one carboxylic ester function, organic compounds with at least one aldehyde function, and organic compounds with at least one keto function.

8. The process according to claim 5, comprises as compound (II) at least one organic compound with at least one ether function is a dihydrocarbyl ether of the general formula R.sup.8OR.sup.9 in which the variables R.sup.8 and R.sup.9 are each independently C.sub.1- to C.sub.20-alkyl radicals, C.sub.1- to C.sub.20-haloalkyl radicals, C.sub.5- to C.sub.8-cycloalkyl radicals, C.sub.6- to C.sub.20-aryl radicals, C.sub.6- to C.sub.20-haloaryl radicals, or C.sub.7- to C.sub.20-arylalkyl radicals is used.

9. The process according to claim 1, wherein the at least one organic compound with at least one ether function comprises at least one ether with at least one secondary or tertiary dihydrocarbyl group, or a halide-substituted hydrocarbyl group.

10. The process according to claim 1, wherein the at least one organic compound with at least one ether function is selected from the group consisting of diethyl ether, di-n-butyl ether, di-isopropyl ether, and di-n-propyl ether, and chloroethyl ethyl ether.

11. The process according to claim 4, wherein the variables R.sup.a to R.sup.c are each independently C.sub.1- to C.sub.20-alkyl groups, and the variables R.sup.b, R.sup.d and R.sup.e each represent hydrogen.

12. The process according to claim 4, wherein the variables R.sup.a and R.sup.c are each independently C.sub.1- to C.sub.20-alkyl groups, and the variables R.sup.b, R.sup.d and R.sup.e are each hydrogen.

13. The process according to claim 4, wherein the variables R.sup.a and R.sup.c are selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, pentyl, n-hexyl, 2-methylpentyl, n-heptyl, n-octyl, 2-ethylhexyl, n-decyl, n-dodecyl, tallow fatty alkyl radicals, and n-eicosyl.

14. The process according to claim 2, wherein the anion X is selected from the group consisting of sulfate, an alkylsulfate, an alkylsulfonate, an alkylcarbonate, a halide, a pseudohalide, a carboxylate, a phosphate, a phosphonate, nitrate, nitrite, the TFSI anion of the formula N(SO.sub.2CF.sub.3).sub.2.sup., and the tricyanomethanide anion.

15. The process according to claim 1, wherein the molar ratio of the aluminum trihalide or alkylaluminum halide to the isobutene monomer used in the case of homopolymerization of isobutene, or to the total amount of the polymerizable monomers used in the case of copolymerization of isobutene, based on each individual functional site of the aluminum trihalide or alkylaluminum halide, is from 0.001:1 to 0.2:1.

16. The process according to claim 1, wherein the polymerization is performed with additional use of a mono- or polyfunctional initiator which is selected from the group consisting of organic hydroxyl compounds in which one or more hydroxyl groups are each bonded to an spa-hybridized carbon atom, organic halogen compounds in which one or more halogen atoms are each bonded to an spa-hybridized carbon atom and water.

17. The process according to claim 14, wherein the initiator is selected from the group consisting of water, methanol, ethanol, 1-phenylethanol, 1-(p-methoxyphenyl)ethanol, n-propanol, isopropanol, 2-phenyl-2-propanol, n-butanol, isobutanol, sec-butanol, tert-butanol, 1-phenyl-1-chloroethane, 2-phenyl-2-chloropropane, tert-butyl chloride and 1,3- or 1,4-bis(1-hydroxy-1-methylethyl)benzene.

18. The process according to claim 14, wherein the molar ratio of the initiators to the isobutene monomer used in the case of homopolymerization of isobutene, or to the total amount of the polymerizable monomers used in the case of copolymerization of isobutene, based on each individual functional site of the initiator, is from 0.0005:1 to 0.1:1, or when water is used as the sole initiator or in combination with organic hydroxyl compounds and/or organic halogen compounds as further initiators, the molar ratio of water to the isobutene monomer used 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 from 0.0001:1 to 0.1:1.

19. The process according to claim 1, wherein the polymerization is performed at a temperature of 90 C. to +30 C.

20. The process according to claim 1, wherein the Lewis Acid-donor complex is dispersed in an inert solvent prior to polymerization.

Description

EXAMPLES

Example 1

The use of [emim]ClAlCl.SUB.3 .as Catalyst

[0261] The polymerization reactions were carried out in glass tubes equipped with a cold finger condenser or, in some cases, in stainless steel reactor with PTFE lining under argon atmosphere at the temperature given in the Tables. As an example of a typical procedure, polymerization was initiated by adding of isobutylene (2.86 g, 5.110.sup.2 mol) to a mixture of a total volume 4.9 mL consisting of solutions of diisopropyl ether (0.11 mL, 1 M), [emim]ClAlCl.sub.3 (0.056 mL) and n-hexane (4.8 mL). After a predetermined time given in the Tables, ca. 2 mL of aqueous ammonia (25%) was poured into the glass reactor to terminate the polymerization. The quenched reaction mixtures were diluted with n-hexane and filtered, evaporated to dryness under reduced pressure, and dried in vacuum (60 C.) to give the product polymers. Monomer conversions were determined gravimetrically.

Example 2

Effect of Ultrasonication

[0262] Polymerization was performed as in Example 1 but the suspension of [emim]ClAlCl.sub.3 in n-hexane was ultrasonicated during 3 min before the addition of isobutylene.

[0263] Process conditions are shown in Table 1 below

Example 3

The Use of [emim]Cl-FeCl.SUB.3 .as Catalyst

[0264] Polymerization was performed as in Example 1 but [emim]ClFeCl.sub.3 was used as catalyst instead of [emim]ClAlCl.sub.3

Example 4

The Use of [emim]ClGaCl.SUB.3 .as Catalyst

[0265] Polymerization was performed as in Example 1 but [emim]ClGaCl.sub.3 was used as catalyst instead of [emim]ClAlCl.sub.3

Example 5

The Use of [bmim]ClTiCl.SUB.4 .as Catalyst

[0266] Polymerization was performed as in Example 1 but [bmim]ClTiCl.sub.4 was used as catalyst instead of [emim]ClAlCl.sub.3

Example 6

The Use of [emim]ClFeCl3 as Catalyst Without an Addition of Ether

[0267] Polymerization was performed as in Example 3 but without an addition of ether.

[0268] Process conditions are shown in the Table 2 below.

[0269] Product yields were determined gravimetrically. The number average molecular weight M.sub.n and the weight average molecular weight M.sub.w was determined by means of Size Exclusion Chromatography (SEC, MnSEC) with polystyrene standards, or by .sup.1H NMR (M.sub.nNMR). The polydispersity PDI=M.sub.w/M.sub.n was calculated using the thus obtained values.

[0270] Composition of reaction products was determined by the .sup.1H-NMR method and assigned to structures as described in Shiman, D. I.; Vasilenko, I. V.; Kostjuk, S. V. Cationic Polymerization of Isobutylene by AlCl.sub.3/Ether Complexes in Non-Polar Solvents: Effect of Ether Structure on the Selectivity of -H Elimination, Polymer2013, 54, 2235-2242, FIG. 4.

[0271] The .sup.1H-NMR shifts are attributed to the structural elements as follows:

[0272] In the context of the present invention the term exo refers to terminal ethylenic double bonds, vinylidene groups or a-double bonds, as shown in the formula on page 1. These terms are used synonymously throughout the text.

[0273] The term Total vinylidene means the terminal ethylenic double bonds referred to as exo above and additionally double bonds located internally at the polymer backbone as shown in the following formula:

##STR00008##

[0274] The terms endo and trisubstituted refer to -double bonds, as shown in the formulae above in the second line. These terms are used synonymously throughout the text.

[0275] Furthermore tetrasubstituted structural elements can be found as shown in the formula at the top right. Furthermore, a chlorinated polyisobutene (PIBCI) was found.

TABLE-US-00001 TABLE 1 Polymerization of Isobutylene in n-Hexane for 30 min Catalyzed by [emim]ClAlCl.sub.3 ((AlCl.sub.3) = 0.6) Ionic Liquid (IL) in the Presence of Diisopropyl Ether .sup.a temp. ether/IL conv. M.sub.n(SEC) M.sub.n(NMR).sup.b end groups distribution (%) run ( C.) (mol/mol) (%) (g mol.sup.1) (g mol.sup.1) M.sub.w/M.sub.n exo endo + tri tetra PIBCI 1 0 .sup.c 100 1500 1360 6.8 2 74 24 0 2 0 0.5 51 3940 3340 2.0 92 4 3 1 2.1.sup.k 0 0.5 65 4200 3600 2.5 89 5 4 2 3.sup.d 0 0.5 12 9350 5170 1.6 86 6 5 3 4.sup.e 0 0.5 90 2700 1510 4.0 3 69 26 2 5.sup.f 0 1.0 28 4900 3240 1.9 95 2 1 2 6 0 0.4 57 7750 4460 1.7 84 6 8 2 7.sup.g 0 0.35 62 6500 4510 1.9 89 4 4 3 8 0 0.3 71 12900 9570 1.8 47 30 19 4 9 20 0.5 54 9200 4630 3.3 36 45 17 2 10 10 0.5 13 5760 6520 2.9 67 15 15 3 11 10 0.5 59 5600 4650 2.0 90 6 3 1 12.sup.h 10 1.0 57 3470 2900 2.7 69 11 17 3 13.sup.i,j 10 0.9 55 1400 1060 3.6 84 5 7 <1 .sup.a [emim]ClAlCl.sub.3 = 22 mM; [IB] = 5.2M. .sup.bCalculated based on the end groups content as M.sub.n(NMR) = 56.11 [(i/2)/((b + b)/2) + d + e + g + k/6], see formula above. .sup.cNo ether was added to the system (for comparison). .sup.dBu.sub.2O was used instead of .sup.iPr.sub.2O. .sup.etBuOMe was used instead of .sup.iPr.sub.2O. .sup.f[emim]ClAlCl.sub.3 = 11 mM; .sup.g[emim]ClAlCl.sub.3 = 33 mM. .sup.hAlCl.sub.3 OiPr.sub.2 (22 mM) was used as catalyst instead of IL. .sup.iEtAlCl.sub.2 O.sup.iPr.sub.2 was used as catalysts instead of IL. .sup.jAmong exo, endo-, tri- and tetra-substituted olefinic groups 4% of coupled polymer chains are presented. .sup.kHexane/IL mixture was ultrasonicated during 3 min

TABLE-US-00002 TABLE 2 Polymerization of Isobutylene in n-Hexane for 30 min at 0 C. Catalyzed by [emim]ClFeCl.sub.3 ((FeCl.sub.3) = 0.6) Ionic Liquid (IL) in the Presence of Diisopropyl Ether .sup.a [IL] ether/IL conv. M.sub.n(SEC) end groups distribution (%) run mM (mol/mol) (%) (g mol.sup.1) M.sub.w/M.sub.n exo endo + tri tetra PIBCI 14 22 0.5 18 1700 2.2 84 7 3 4 15 33 0.33 32 2600 2.4 85 6 5 2 16 44 0.25 95 1800 2.5 87 8 3 1 17.sup.b 11 1.0 20 3500 1.9 85 7 4 3 18 22 0.5 18 1700 2.2 84 7 3 4 19.sup.b 22 0.5 30 2500 2.6 87 6 3 3 20 33 0.33 32 2600 2.4 85 6 5 2 21.sup.b 33 0.33 71 2900 1.9 85 10 3 1 22 44 0.25 95 1800 2.5 87 8 3 1 23.sup.b,c 44 0.25 61 2700 2.1 84 7 5 1 24.sup.b 44 0.25 100 1800 3.8 77 12 9 1 25.sup.b,d 22 0.5 83 700 2.3 84 8 1 0 26.sup.e 22 0.5 21 1980 1.9 87 3 2 8 27.sup.f 22 0.5 12 2500 5.2 86 5 8 1 28.sup.g 22 27 5400 3.8 54 20 19 7 .sup.a [IB] = 4.8M .sup.bHexane/IL mixture was ultrasonicated during 3 min .sup.cReaction time: 10 min .sup.dClEtOEt was used instead of diisopropyl ether .sup.e[emim]ClGaCl.sub.3 was used as catalyst instead of [emim]ClFeCl.sub.3 .sup.f[bmim]ClTiCl.sub.4 was used as catalyst instead of [emim]ClFeCl.sub.3 .sup.gNo ether was added to the system (for comparison)