Process for preparing high-reactivity isobutene homo- or copolymers

Abstract

The present invention relates to 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 %, which comprises polymerizing isobutene or an isobutene-comprising monomer mixture in the presence of an aluminum trihalide-donor complex effective as a polymerization catalyst or an alkylaluminum halide-donor complex effective as a polymerization catalyst, wherein the aluminum trihalide or alkylaluminum halide is treated with at least one inorganic hydrate.

Claims

1. A process for preparing high-reactivity isobutene homo- or copolymers having a number-average molecular weight Mn (determined by gel permeation chromatography) of 500 to 25 000 g/mol and a content of terminal vinylidene double bonds per polyisobutene chain end of at least 70 mol % based on a total amount of chain ends, the process comprising: polymerizing isobutene or an isobutene-comprising monomer mixture in the presence of an aluminum trihalide-donor complex or an alkylaluminum halide-donor complex, wherein the aluminum trihalide of the aluminum trihalide-donor complex and the alkylaluminum halide of the alkylaluminum halide-donor complex are each treated with at least one inorganic hydrate, wherein a molar ratio of total water bound as water of crystallization in the at least one inorganic hydrate to the aluminum trihalide or alkylaluminum halide is 0.001:1 to 0.4:1, wherein the at least one inorganic hydrate is an ionic compound of formula:
[M.sup.m+.sub.xA.sup.a−.sub.y]×z H.sub.2O, wherein: a, m, x, and y are positive natural numbers, with the proviso that x×m=y×a; z is a positive rational number; wherein M.sup.m+ is an m-fold positively charged cation; wherein A.sup.a− is an a-fold negatively charged anion; and wherein M is selected from the main groups 1, 2, and 3, and the transition groups 6, 7, 8, and 1 of the Periodic Table of the Elements.

2. The process according to claim 1, wherein the at least one inorganic hydrate is a solid ionic compound which comprises fixed stoichiometric amounts of water of crystallization, wherein at least one water molecule is located at a fixed position of a crystal lattice.

3. The process according to claim 1, wherein the aluminum trihalide-donor complex is an aluminum trichloride-donor complex, and wherein the alkylaluminum halide-donor complex is an alkyl aluminum chloride-donor complex or the alkylaluminum halide-donor complex is a dialkyl aluminum chloride-donor complex.

4. The process according to claim 1, wherein the aluminum trihalide-donor complex is an aluminum trichloride-donor complex, and wherein the alkylaluminum halide-donor complex is a methylaluminum dichloride-donor complex, an ethylaluminum dichloride-donor complex, or an iso-butylaluminum dichloride-donor complex.

5. The process according to claim 1, wherein a, m, x, and y are each independently 1, 2, 3, or 4.

6. The process according to claim 1, wherein z is greater than 0 and less than or equal to 18.

7. The process according to claim 1, wherein cations M.sup.m+ are selected from the group consisting of Cs.sup.+, Rb.sup.+, K.sup.+, NH.sup.4+, Na.sup.+, Li.sup.+, Ba.sup.2+, Sr.sup.2+, Ca.sup.2+, Mg.sup.2+, Zn.sup.2+, Ni.sup.2+, Cu.sup.2+, Al.sup.3+, Mn.sup.2+, Fe.sup.2+, Fe.sup.3+, and Cr.sup.3+.

8. The process according to claim 1, wherein anions A.sup.a− are selected from the group consisting of NO.sup.3−, CN.sup.−, I.sup.−, Br.sup.−, Cl.sup.−, F.sup.−, SO.sub.4.sup.2−, and CO.sub.3.sup.2−.

9. The process according to claim 1, wherein the at least one inorganic hydrate is selected from the group consisting of Na.sub.2CO.sub.3×10H.sub.2O, Na.sub.2CO.sub.3×1H.sub.2O, Na.sub.2SO.sub.4×10H.sub.2O, NiSO.sub.4×7H.sub.2O, ZnSO.sub.4×7H.sub.2O, ZnCl.sub.2×2H.sub.2O, FeSO.sub.4×7H.sub.2O, MnSO.sub.4×1H.sub.2O, MnSO.sub.4×4H.sub.2O, MgCl.sub.2×6H.sub.2O, Mg(OH).sub.2×4H.sub.2O, MgCO.sub.3×4H.sub.2O, MgSO.sub.4×7H.sub.2O, MgSO.sub.4×1H.sub.2O, K.sub.2Mg(SO.sub.4).sub.2×6H.sub.2O, (NH.sub.4).sub.2Mg(SO.sub.4).sub.2×6H.sub.2O, CaCl.sub.2×6H.sub.2O, CaSO.sub.4×2H.sub.2O, CuCl.sub.2×2H.sub.2O, CuSO.sub.4×5H.sub.2O, IOCuSO.sub.4×3H.sub.2O, CuSO.sub.4×1H.sub.2O, CoCl.sub.2×6H.sub.2O, CoCl×4H.sub.2O, CoCl.sub.2×2H.sub.2O, CoCl.sub.2×1.5H.sub.2O, CoCl.sub.2×1H.sub.2O, CoSO.sub.4×7H.sub.2O, Al.sub.2(SO.sub.4).sub.3×18H.sub.2O, Al.sub.2(SO.sub.4).sub.3×16H.sub.2O, Al.sub.2(SO.sub.4).sub.3×10H.sub.2O, Al.sub.2(SO.sub.4).sub.3×6H.sub.2O, and KAl(SO.sub.4).sub.2×12H.sub.2O.

10. The process according to claim 1, wherein the donor of the aluminum trihalide-donor complex and the donor of the alkylaluminum halide-donor complex are each independently selected from the group consisting of compounds with at least one ether function, compounds with at least one carboxylic ester function, alcohols, aldehydes, ketones, phenols, acetals, and hemiacetals.

11. The process according to claim 1, wherein the donor of the aluminum trihalide-donor complex and the donor of the alkylaluminum halide-donor complex are each independently dihydrocarbyl ethers of formula R.sup.1—O—R.sup.2, in which the variables R.sup.1 and R.sup.2 are each independently selected from the group consisting of C.sub.1- to C.sub.4-alkyl radicals, C.sub.6- to C.sub.12-aryl radicals, and C.sub.7- to C.sub.12-arylalkyl radicals.

12. The process according to claim 1, wherein the polymerization is performed at a temperature from −90° C. to +30° C.

13. The process according to claim 1, wherein the aluminum trihalide-donor complex and the alkylaluminum halide-donor complex are prepared separately from the polymerization.

Description

EXAMPLES

(1) 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 10° C.

(2) As an example of a typical procedure, the pre-activation of .sup.iBuAlCl.sub.2 was carried out in glass reactor under argon atmosphere at room temperature. The required amount of MgSO.sub.4×7H.sub.2O (0.026 g) was placed into the flask. Then, 5 mL of 1 M solution of .sup.iBuAlCl.sub.2 in toluene (or n-hexane) was added into the flask and reaction mixture was stirred until complete dissolution of salt.

(3) As an example of a typical procedure, polymerization was initiated by adding isobutylene (3.25 g, 5.8×10.sup.−2 mol) to a mixture of a total volume of 5.25 mL, consisting of solutions of diisopropyl ether (0.18 mL, 1 M) and BuAlCl.sub.2 (0.22 mL, 1M) in n-hexane (or toluene), and n-hexane (4.8 mL). Then, 3 min after beginning of the reaction, 6 μL (3.3×10.sup.−4 mol) of deionized H.sub.2O was introduced into the system via microsyringe. After a predetermined reaction time, ca. 2 mL of ethanol was poured into the reactor to terminate the polymerization. The quenched reaction mixtures were diluted by n-hexane, washed with 0.5 M nitric acid and deionized water to remove the aluminum-containing residues, evaporated to dryness under reduced pressure, and dried in vacuum (≤60° C.) to give the polymeric products.

(4) 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, M.sub.nSEC) 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.

(5) Composition of reaction products was determined by the .sup.1H-NMR method and assigned to structures as described in AnRu Guo, Xiao-Jian Yang, Peng-Fei Yan, Yi-Xian Wu, Journal of Polymer Science, Part A: Polymer Chemistry 2013, 51, 4200-4212, see especially pages 4205 and FIG. 5 on page 4206.

(6) In the context of the present invention the term “exo” refers to terminal ethylenic double bonds, vinylidene groups or α-double bonds, as shown in the formula on page 1. These terms are used synonymously throughout the text.

(7) 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 formula on the right:

(8) ##STR00006##

(9) The term “trisubstituted” refers to β-double bonds, as shown in the formulae bottom left and bottom centre. These terms are used synonymously throughout the text.

(10) Furthermore “tetrasubstituted” structural elements can be found as shown in the formula at the top centre.

Example 1 (Comparative)

(11) A polymerization reaction was run as described above. Reaction time was 10 min. A polyisobutene polymer with M.sub.nSEC=1300 g/mol (M.sub.nNMR=820 g/mol) was obtained in 46% yield. Polydispersity and double bond distribution of the polymer are shown on Table 1.

(12) TABLE-US-00001 TABLE 1 Total Tri- Tetra- Example PDI Exo vinylidene substituted substituted 1 3.8 90 93 3 4

Example 2 (Comparative)

(13) A polymerization reaction was run as described above but .sup.iBuAlCl.sub.12 was previously preactivated by bubbling argon in a slow flow first through a washing flask with water and then through an n-hexane solution of the catalyst during 10 min. Polymerization time was 10 min. A polyisobutene polymer with M.sub.nSEC=1390 g/mol (M.sub.nNMR=1130 g/mol) was obtained in 82% yield. Polydispersity and double bond distribution of the polymer are shown on Table 2.

(14) TABLE-US-00002 TABLE 2 Total Tri- Tetra- Example PDI Exo vinylidene substituted substituted 2 3.9 78 80 9 11

Example 3

(15) A polymerization reaction was run as described above but .sup.iBuAlCl.sub.2 was previously preactivated by dissolving MgCl.sub.2×6H.sub.2O (2 mol % H.sub.2O to catalyst) in a 1M n-hexane solution of the catalyst. Polymerization time was 10 min. A polyisobutene polymer with M.sub.nSEC=1600 g/mol (M.sub.nNMR=1020 g/mol) was obtained in 55% yield. Polydispersity and double bond distribution of the polymer are shown on Table 3.

(16) TABLE-US-00003 TABLE 3 Total Tri- Tetra- Example PDI Exo vinylidene substituted substituted 3 4.2 90 91 4 5

Example 4

(17) A polymerization reaction was run as described above but .sup.iBuAlCl.sub.12 was previously preactivated by dissolving CuSO.sub.4×5H.sub.2O (8 mol % H.sub.2O to catalyst) in a 1M n-hexane solution of the catalyst. Polymerization time was 10 min. A polyisobutene polymer with M.sub.nSEC=1200 g/mol (M.sub.nNMR=910 g/mol) was obtained in 69% yield. Double bond distribution of the polymer is shown on Table 4.

(18) TABLE-US-00004 TABLE 4 Total Tri- Tetra- Example PDI Exo vinylidene substituted substituted 4 4.0 87 88 5 7

Example 5

(19) A polymerization reaction was run as described above but .sup.iBuAlCl.sub.2 was previously preactivated by dissolving CuSO.sub.4×5H.sub.2O (10% mol % H.sub.2O to catalyst) in a 1M n-hexane solution of the catalyst. Polymerization time was 10 min. A polyisobutene polymer with M.sub.nSEC=1190 g/mol (M.sub.nNMR=1390 g/mol) was obtained in 59% yield. Double bond distribution of the polymer is shown on Table 5.

(20) TABLE-US-00005 TABLE 5 Total Tri- Tetra- Example PDI Exo vinylidene substituted substituted 5 4.1 78 80 9 11

Example 6

(21) A polymerization reaction was run as described above but .sup.iBuAlCl.sub.2 was previously preactivated by dissolving MgSO.sub.4×7H.sub.2O (15 mol % H.sub.2O to catalyst) in a 1M n-hexane solution of the catalyst. Polymerization time was 10 min. A polyisobutene polymer with M.sub.nSEC=1070 g/mol (M.sub.nNMR=1250 g/mol) was obtained in 62% yield. Polydispersity and double bond distribution of the polymer are shown on Table 6.

(22) TABLE-US-00006 TABLE 6 Total Tri- Tetra- Example PDI Exo vinylidene substituted substituted 6 2.8 81 84 7 9

Example 7

(23) A polymerization reaction was run as described above but .sup.iBuAlCl.sub.2 was previously preactivated by dissolving MgSO.sub.4×7H.sub.2O (10% mol % H.sub.2O to catalyst) in a 1M n-hexane solution of the catalyst. Polymerization time was 10 min. A polyisobutene polymer with M.sub.nSEC=1070 g/mol (M.sub.nNMR=1250 g/mol) was obtained in 60% yield. Double bond distribution of the polymer is shown on Table 7

(24) TABLE-US-00007 TABLE 7 Total Tri- Tetra- Example PDI Exo vinylidene substituted substituted 7 2.8 78 84 7 9

Example 8

(25) A polymerization reaction was run as described above but .sup.iBuAlCl.sub.2 was previously preactivated by dissolving MgSO.sub.4×7H.sub.2O (30 mol % H.sub.2O to catalyst) in a 1M n-hexane solution of the catalyst. Polymerization time was 10 min. A polyisobutene polymer with M.sub.nSEC=1760 g/mol (M.sub.nNMR=1540 g/mol) was obtained in 70% yield. Polydispersity and double bond distribution of the polymer are shown on Table 8.

(26) TABLE-US-00008 TABLE 8 Total Tri- Tetra- Example PDI Exo vinylidene substituted substituted 8 3.0 81 81 9 10

Example 9 (Comparative)

(27) A polymerization reaction was run as described above but the mixture .sup.iBuAlCl.sub.2+OiPr.sub.2 was previously preactivated by adding 0.033 M water in a 1M n-hexane solution of the catalyst. An intense reaction and formation of a precipitate was observed.

(28) Polymerization time was 10 min. A polyisobutene polymer (non-characterized) was obtained in 4% yield.