Abstract
Unsymmetrical metallocene compounds based on cyclopentadienyl ligands are disclosed, as well as catalytic compositions comprising the compounds supported on solid support materials. The compounds and compositions are useful as catalysts in the polymerisation of olefins. In particular, the compounds and compositions are useful catalysts in the preparation of low molecular weight polyethylene (e.g. polyethylene wax) and copolymers formed from the polymerisation of ethylene and other -olefins.
Claims
1. A compound of formula (I): ##STR00023## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are each independently selected from hydrogen or (1-4C)alkyl; R.sub.a and R.sub.b are each independently (1-4C)alkyl; X is zirconium or hafnium; and each Y is independently selected from halo, phenyl, aryl(1-2C)alkyl, or (CH.sub.2).sub.zSi(CH.sub.3).sub.3, any of which is optionally substituted with one or more (1-3C)alkyl or halo; wherein z is 1, 2 or 3; or each Y is independently chloro, methyl, propyl, neopentyl, phenyl, benzyl, or CH.sub.2Si(CH.sub.3).sub.3; with the proviso that at least one of R.sub.1, R.sub.2, R.sub.3 and R.sub.4 is not hydrogen.
2. The compound of claim 1, wherein each Y is independently chloro, methyl, propyl, neopentyl, phenyl, benzyl, or CH.sub.2Si(CH.sub.3).sub.3.
3. The compound of claim 1, wherein at least one Y group is chloro, methyl or benzyl.
4. The compound of claim 1, wherein both Y groups are chloro, methyl or benzyl.
5. The compound of claim 1, wherein the compound of formula (I) has a structure according to formula (Ia) or (Ib): ##STR00024## wherein R.sub.a and R.sub.b are each independently (1-4C)alkyl; each Y is independently selected from halo, phenyl, aryl(1-2C)alkyl, or (CH.sub.2).sub.zSi(CH.sub.3).sub.3, any of which is optionally substituted with one or more (1-3C)alkyl or halo; m is 1, 2, 3, or 4; and Q is n-butyl or t-butyl.
6. The compound of claim 1, wherein the compound has a structure according to formula (Ie) or (If): ##STR00025## wherein m is 1, 2 3 or 4; and Q is n-butyl or t-butyl.
7. The compound of claim 1, wherein the compound has any one of the following structures: ##STR00026##
8. A composition comprising the compound of formula (I) of claim 1, and a support material.
9. The composition of claim 8, wherein the support material is solid MAO.
10. The composition of claim 9, wherein a mole ratio of support material to the compound of formula (I) is 50:1 to 500:1.
11. A polymerisation process comprising the step of polymerising one or more olefins in the presence of the composition of claim 8.
12. The process of claim 11, wherein the one or more olefins is ethylene.
13. The process of claim 12, wherein ethylene is polymerised in the presence of hydrogen.
14. The process of claim 13, wherein a mole ratio of hydrogen to ethylene ranges from 0.005:1 to 0.08:1.
15. The process of claim 11, wherein the one or more olefins is ethylene and one or more (3-8C)-olefin.
16. The process of claim 15, wherein a quantity of the one or more (3-8C)-olefin, relative to a quantity of ethylene, is 0.05-10 mol %.
17. The process of claim 15, where the step of polymerizing is conducted in the presence of one of more compounds selected from triethyl aluminium, methyl aluminoxane, trimethyl aluminium and triisobutyl aluminium.
18. A polymerisation process comprising a step of: polymerising ethylene in the presence of hydrogen and a composition comprising solid MAO and a compound according to formula (II) ##STR00027## wherein X is zirconium or hafnium; wherein a mole ratio of hydrogen to ethylene ranges from 0.0365:1 to 0.3:1.
19. The process of claim 18, wherein a mole ratio of solid MAO to the compound of formula (II) is 125:1 to 400:1.
20. The process of claim 18, where the step of polymerizing is conducted in the presence of one of more compounds selected from triethyl aluminium, methyl aluminoxane, trimethyl aluminium or triisobutyl aluminium.
Description
EXAMPLES
(1) Examples of the invention will now be described, for the purpose of illustration only, with reference to the accompanying figures, in which:
(2) FIG. 1 shows the .sup.1H NMR spectrum of .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 (298 K, 400 MHz, chloroform-d.sub.1).
(3) FIG. 2 shows the .sup.1H NMR spectrum of .sup.Me.sup.2SB(Cp.sup.nBu,I*)ZrCl.sub.2 (298 K, 400 MHz, chloroform-d.sub.1).
(4) FIG. 3 shows activity vs temperature of polymerisation of ethylene using solid MAO supported/.sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2: [Al].sub.0/[Zr].sub.0=300 (black square), [Al].sub.0/[Zr].sub.0=200 (red circle), [Al].sub.0/[Zr].sub.0=150 (blue triangle) and [Al].sub.0/[Zr].sub.0=100 (inverted pink triangle). Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 30 minutes, and 150 mg of TIBA.
(5) FIG. 4 shows activity vs time of polymerisation of ethylene using solid MAO supported/.sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2: [Al].sub.0/[Zr].sub.0=300 (black square), [Al].sub.0/[Zr].sub.0=200 (red circle), [Al].sub.0/[Zr].sub.0=150 (blue triangle) and [Al].sub.0/[Zr].sub.0=300 (inverted pink triangle). Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 70 C., and 150 mg of TIBA.
(6) FIG. 5 shows activity vs temperature of polymerisation of ethylene using solid MAO supported/.sup.Me.sup.2SB(Cp,I*)HfCl.sub.2: [Al].sub.0/[Zr].sub.0=200 (black square), [Al].sub.0/[Zr].sub.0=150 (red circle), and [Al].sub.0/[Zr].sub.0=100 (blue triangle). Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 30 minutes, and 150 mg of TIBA.
(7) FIG. 6 shows activity vs time of polymerisation of ethylene using solid MAO supported/.sup.Me.sup.2SB(Cp,I*)HfCl.sub.2: [Al].sub.0/[Zr].sub.0=200 (black square), [Al].sub.0/[Zr].sub.0=150 (red circle), and [Al].sub.0/[Zr].sub.0=100 (blue triangle). Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 30 minutes, and 150 mg of TIBA.
(8) FIG. 7 shows Productivity vs temperature for solid MAO supported/.sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2: [Al].sub.0/[Zr].sub.0=300 (black square), [Al].sub.0/[Zr].sub.0=200 (red circle), [Al].sub.0/[Zr].sub.0=150 (blue triangle) and [Al].sub.0/[Zr].sub.0=100 (inverted pink triangle). Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 30 minutes, and 150 mg of TIBA.
(9) FIG. 8 shows Productivity vs temperature for solid MAO supported/.sup.Me.sup.2SB(Cp,I*)HfCl.sub.2: [Al].sub.0/[Zr].sub.0=300 (black square), [Al].sub.0/[Zr].sub.0=200 (red circle), [Al].sub.0/[Zr].sub.0=150 (blue triangle) and [Al].sub.0/[Zr].sub.0=100 (inverted pink triangle). Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 30 minutes, and 150 mg of TIBA.
(10) FIG. 9 shows productivity (black, left vertical axis) and molecular weights (blue, right vertical axis) vs H.sub.2 content used as co-feed using solid MAO supported/.sup.Me2SB(Cp,I*)ZrCl.sub.2 with [Al].sub.0/[Zr].sub.0 ratio of 200 (square), 150 (circle) and 100 (triangle). Polymerisation conditions: 0.05 mg of catalyst, 5 mL heptane, 8 bar and 80 C.
(11) FIG. 10 shows Molecular weights, M.sub.w, (horizontal axis) for the homopolymerisation and PE wax formation using Solid MAO/.sup.Me2SB(Cp,I*)ZrCl.sub.2 catalyst using various [Al].sub.0/[Zr].sub.0 ratio. Polymerisation conditions: 0.05 mg of catalyst, 5 mL heptane, 8 bar and 80 C.
(12) FIG. 11 shows uptake rate of ethylene for ethylene polymerisation with hydrogen response using Solid MAO/.sup.Me2SB(Cp,I*)ZrCl.sub.2 catalyst using [Al].sub.0/[Zr].sub.0 ratio of 100 (left) and 150 (right). Polymerisation conditions: 0.05 mg of catalyst, 5 mL heptane, 8 bar and 80 C.
(13) FIG. 12 shows molecular weights, M.sub.w, of ethylene polymerisation with hydrogen response using Solid MAO/.sup.Me2SB(Cp,I*)ZrCl.sub.2 catalyst using [Al].sub.0/[Zr].sub.0 ratio of 100 (left) and 150 (right). Polymerisation conditions: 0.05 mg of catalyst, 5 mL heptane, 8 bar and 80 C.
(14) FIG. 13 shows uptake rate of ethylene for copolymerisation of ethylene and 1-hexene; using Solid MAO/.sup.Me2SB(Cp,I*)ZrCl.sub.2 catalyst using [Al].sub.0/[Zr].sub.0 ratio of 100 (left) and 150 (right). Polymerisation conditions: 0.05 mg of catalyst, 5 mL heptane, 8 bar and 80 C.
(15) FIG. 14 shows molecular weights, M.sub.w, for copolymerisation of ethylene and 1-hexene using Solid MAO/.sup.Me2SB(Cp,I*)ZrCl.sub.2 catalyst using [Al].sub.0/[Zr].sub.0 ratio of 100 (left) and 150 (right). Polymerisation conditions: 0.05 mg of catalyst, 5 mL heptane, 8 bar and 80 C.
(16) FIG. 15 shows CEF traces for the copolymerisation of ethylene and 1-hexene using Solid MAO/.sup.Me2SB(Cp,I*)ZrCl.sub.2 catalyst using [Al].sub.0/[Zr].sub.0 ratio of 100 (left) and 150 (right). Polymerisation conditions: 0.05 mg of catalyst, 5 mL heptane, 8 bar and 80 CC.
(17) FIG. 16 shows the .sup.1H NMR spectrum of two isomers of .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 in a 40:60 ratio with the methyl group on the cyclopentadienyl ring (298 K, 400 MHz, benzene-d.sub.6).
(18) FIG. 17 shows the .sup.1H NMR spectrum of one isomer of .sup.Me.sup.2SB(Cp.sup.nBu,I*)ZrCl.sub.2 with the n-butyl group on the cyclopentadienyl ring (298 K, 400 MHz, benzene-d.sub.6).
(19) FIG. 18 shows the .sup.1H NMR spectrum of the other isomer of .sup.Me.sup.2SB(Cp.sup.nBu,I*)ZrCl.sub.2 with the n-butyl group on the cyclopentadienyl ring (298 K, 400 MHz, benzene-d.sub.6).
(20) FIG. 19 shows the .sup.1H NMR spectrum of one isomer of .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrBr.sub.2 (298 K, 400 MHz, benzene-4).
(21) FIG. 20 shows the .sup.1H NMR spectrum of two isomers of .sup.Me.sup.2SB(Cp.sup.Me,I*)Zr(CH.sub.2Ph).sub.2 in a 40:60 ratio with the methyl group on the cyclopentadienyl ring (298 K, 400 MHz, benzene-d.sub.6).
(22) FIG. 21 shows the .sup.1H NMR spectrum of two isomers of .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrMe.sub.2 in a 40:60 ratio with the methyl group on the cyclopentadienyl ring (298 K, 400 MHz, benzene-d.sub.6).
(23) FIG. 22 shows the crystal structures for .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 and .sup.Me.sup.2SB(Cp.sup.nBu,I*)ZrCl.sub.2.
(24) FIG. 23 shows activity vs temperature of polymerisation of ethylene using solid MAO supported/.sup.Me.sup.2SB(Cp.sup.Me,I*)ZrMe.sub.2 (circle), .sup.Me.sup.2SB(Cp.sup.Me, I*)Zr(CH.sub.2Ph).sub.2 (inverted triangle), .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 (triangle). Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 30 minutes, 150 mg of TIBA and [Al].sub.0/[Zr].sub.0=200.
(25) FIG. 24 shows activity vs time of polymerisation of ethylene using solid MAO supported/.sup.Me.sup.2SB(Cp.sup.Me,I*)ZrMe.sub.2 (circle), .sup.Me.sup.2SB(Cp.sup.Me, I*)Zr(CH.sub.2Ph).sub.2 (inverted triangle), .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 (triangle). Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 80 C., 150 mg of TIBA and [Al].sub.0/[Zr].sub.0=200.
(26) FIG. 25 shows productivity vs temperature of polymerisation of ethylene using solid MAO supported/.sup.Me.sup.2SB(Cp.sup.Me,I*)ZrMe.sub.2 (circle), .sup.Me.sup.2SB(Cp.sup.Me,I*)Zr(CH.sub.2Ph).sub.2 (inverted triangle), .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 (triangle). Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 30 minutes, 150 mg of TIBA and [Al].sub.0/[Zr].sub.0=200.
(27) FIG. 26 shows productivity vs time of polymerisation of ethylene using solid MAO supported/.sup.Me.sup.2SB(Cp.sup.Me,I*)ZrMe.sub.2 (circle), .sup.Me.sup.2SB(Cp.sup.Me, I*)Zr(CH.sub.2Ph).sub.2 (inverted triangle), .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 (triangle). Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 80 C., 150 mg of TIBA and [Al].sub.0/[Zr].sub.0=200.
(28) FIG. 27 shows activity vs temperature (left) and activity vs. time (right) of polymerisation of ethylene using .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 supported on Solid MAO (square), MAO modified LDH, LDHMAO/Mg.sub.3AlCO.sub.3, (triangle) and MAO modified silica, ssMAO, (circle). Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 150 mg of TIBA and [Al].sub.0/[Zr].sub.0=200.
(29) FIG. 28 shows activity vs temperature (left) and activity vs. time (right) of polymerisation of ethylene using .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 supported on Solid MAO (square), MAO modified LDH, LDHMAO/Mg.sub.3AlCO.sub.3, (triangle) and MAO modified silica, ssMAO, (circle). Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 150 mg of TIBA and [Al].sub.0/[Zr].sub.0=200.
(30) FIG. 29 shows activity vs amount of immobilised complex for polymerising ethylene using solid MAO supported/.sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2. Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 150 mg of TIBA, 30 min and 80 CC.
(31) FIG. 30 shows activity vs amount of TIBA for polymerising ethylene using solid MAO supported/.sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 (square) and solid MAO supported/.sup.Me.sup.2SB(Cp.sup.Me, I*)Zr(CH.sub.2Ph).sub.2 (inverted triangle). Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 30 min and 80 C.
(32) FIG. 31 shows activity vs varying activators for polymerising ethylene using solid MAO supported/.sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 and solid MAO supported/.sup.Me.sup.2SB(Cp.sup.Me,I*)Zr(CH.sub.2Ph).sub.2. Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 30 min and 80 (C.
(33) FIG. 32 shows SEM images for the polyethylene produced from solid MAO supported/.sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2, .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 and .sup.Me.sup.2SB(Cp,I*)HfCl.sub.2, and MAO modified LDH, LDHMAO/Mg.sub.3AlCO.sub.3, supported .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2, Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 30 min and 80 CC.
(34) FIG. 33 shows uptake rate of ethylene for ethylene polymerisation with hydrogen response using Solid MAO/.sup.Me2SB(Cp.sup.Me,I*)ZrCl.sub.2 catalyst with [Al].sub.0/[Zr].sub.0 ratio of 200. Polymerisation conditions: 0.05 mg of catalyst, 5 mL heptane, 8 bar and 80 C.
(35) FIG. 34 shows molecular weights, M.sub.w, of ethylene polymerisation with hydrogen response using Solid MAO/.sup.Me2SB(Cp.sup.Me,I*)ZrCl.sub.2 catalyst with [Al].sub.0/[Zr].sub.0 ratio of 200. Polymerisation conditions: 0.05 mg of catalyst, 5 mL heptane, 8 bar and 80 C.
(36) FIG. 35 shows uptake rate of ethylene for copolymerisation of ethylene and 1-hexene; using Solid MAO/.sup.Me2SB(Cp.sup.Me,I*)ZrCl.sub.2 catalyst with [Al].sub.0/[Zr].sub.0 ratio of 200. Polymerisation conditions: 0.05 mg of catalyst, 5 mL heptane, 8 bar and 80 C.
(37) FIG. 36 shows molecular weights, M.sub.w, for copolymerisation of ethylene and 1-hexene using Solid MAO/.sup.Me2SB(Cp.sup.Me,I*)ZrCl.sub.2 catalyst with [Al].sub.0/[Zr].sub.0 ratio of 200. Polymerisation conditions: 0.05 mg of catalyst, 5 mL heptane, 8 bar and 80 C.
(38) FIG. 37 shows CEF traces for the copolymerisation of ethylene and 1-hexene using Solid MAO/.sup.Me2SB(Cp.sup.Me,I*)ZrCl.sub.2 catalyst with [Al].sub.0/[Zr].sub.0 ratio of 200. Polymerisation conditions: 0.05 mg of catalyst, 5 mL heptane, 8 bar and 80 C.
(39) FIG. 38 Shows molecular weight vs temperature of polymerisation of ethylene using solid MAO supported/.sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2. Polymerisation conditions: 10 mg of catalyst, 50 mL hexanes, 2 bar, 30 minutes, 80 C., 150 mg of TIBA and [Al].sub.0/[Zr].sub.0=200.
EXAMPLES
Example 1Synthesis of Compounds
(40) Scheme 1a below illustrates the synthesis of various unsymmetrical .sup.Me.sup.2SB(Cp.sup.R,I*)ZrCl.sub.2 compounds of the invention (in which SB denotes silicon bridged, Cp.sup.R denotes cyclopentadienyl substituted with R, and I* denotes per-methyl indenyl). All the reactions were carried out in pseudo one-pot synthesis from the chloro silane synthon, Ind*SiMe.sub.2Cl, using the corresponding alkali salt in tetrahydrofuran, followed by a lithiation reaction in tetrahydrofuran and finally the complexation step using zirconium tetrachloride in benzene.
(41) ##STR00017##
(42) FIG. 1 shows the .sup.1H NMR spectrum of .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 (298 K, 400 MHz, chloroform-d.sub.1). FIG. 2 shows the .sup.1H NMR spectrum of .sup.Me.sup.2SB(Cp.sup.nBu,I*)ZrCl.sub.2 (298 K, 400 MHz, chloroform-d.sub.1). The .sup.1H NMR spectra of the bulk materials for .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 and .sup.Me.sup.2SB(Cp.sup.nBu,I*)ZrCl.sub.2 demonstrated the presence of two isomers based around the cyclopentadienyl ligand.
(43) Scheme 1b below illustrates the synthesis of various unsymmetrical .sup.Me.sup.2SB(Cp.sup.R,I*)ZrCl.sub.2 compounds of the invention (in which SB denotes silicon bridged, Cp.sup.R denotes cyclopentadienyl substituted with R, and I* denotes per-methyl indenyl). All the reactions were carried out in pseudo one-pot synthesis from the chloro silane synthon, Ind*SiMe.sub.2Cl, using the corresponding alkali salt in tetrahydrofuran, followed by a lithiation reaction in tetrahydrofuran and finally the complexation step using zirconium tetrachloride in benzene.
(44) ##STR00018##
(45) FIGS. 16 to 21 shows the .sup.1H NMR spectroscopy for .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2, .sup.Me.sup.2SB(Cp.sup.nBu,I*), .sup.Me.sup.2SB(Cp.sup.nBu,I*)ZrCl.sub.2, .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrBr.sub.2, .sup.Me.sup.2SB(Cp.sup.Me,I*)Zr(CH.sub.2Ph).sub.2 and .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrMe.sub.2 at 25 C. in benzene-d highlighting the resonances due to each complex. FIG. 22 shows the molecular structures for .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 and .sup.Me.sup.2SB(Cp.sup.nBu,I*)ZrCl.sub.2.
Example 2Ethylene Homopolymerisation Studies
(46) In addition to those compounds synthesised in Example 1, .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 and .sup.Me.sup.2SB(Cp.sup.Me,I*)HfCl.sub.2 (in which the Cp group is unsubstituted, shown below) were also prepared, which were then reacted with solid MAO at various loadings (aluminium to Hf/Zr ratio).
(47) The solid MAO used in this Example may be prepared via an adaptation of the optimised procedure in Kaji et al. in the U.S. Pat. No. 8,404,880 B2 embodiment 1 (Scheme 1). For brevity, each synthesised solid MAO is represented as solid MAO(Step 1 Al:O ratio/Step 2 temperature in C.,time in h/Step 3 temperature in C.,time in h). Hence, the synthesis conditions outlined in Scheme 2 below would yield solid MAO(1.2/70,32/100,12).
(48) ##STR00019##
(49) A Rotaflo ampoule containing a solution of trimethyl aluminium (2.139 g, 2.967 mmol) in toluene (8 mL) was cooled to 15 C. with rapid stirring, and benzoic acid (1.509 g, 1.239 mmol) was added under a flush of N.sub.2 over a period of 30 min. Effervescence (presumably methane gas, MeH) was observed and the reaction mixture appeared as a white suspension, which was allowed to warm to room temperature. After 30 min the mixture appeared as a colourless solution and was heated in an oil bath at 70 C. for 32 h (a stir rate of 500 rpm was used). The mixture obtained was a colourless solution free of gelatinous material, which was subsequently heated at 100 C. for 12 h. The reaction mixture was cooled to room temperature and hexane (40 mL) added, resulting in the precipitation of a white solid which was isolated by filtration, washed with hexane (240 mL) and dried in vacuo for 3 h. Total yield=1.399 g (71% based on 40 wt % Al).
(50) Once the solid MAO is prepared, different quantities of the various metallocene compounds were supported on it (represented by varying aluminium to Hf/Zr ratios). In the glovebox, the solid MAO and the complex are weighed out in a Schlenk tube. Toluene (50 mL) is added to the Schlenk and the reaction mixture swirled at 60 C. for one hour. The coloured solid is allowed to settle from the clear, colourless solution which is decanted, and the solid is dried in vacuo (40 C., 110.sup.2 mbar). The product is scraped out in the glovebox in quantitative yield.
(51) The catalytic properties of the solid MAO supported .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 and .sup.Me.sup.2SB(Cp.sup.Me,I*)HfCl.sub.2 metallocenes were investigated.
(52) ##STR00020##
(53) FIG. 3 shows the catalytic activity of various solid MAO supported .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 compositions as a function of temperature, in the homopolymerisation of ethylene. FIG. 4 shows the catalytic activity of various solid MAO supported .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 compositions as a function of time, in the homopolymerisation of ethylene. FIGS. 3 and 4 demonstrate that the aluminium to zirconium ratio [Al].sub.0/[Zr].sub.0 of 300 afforded the highest activity over time and temperature of polymerisation.
(54) FIG. 5 shows the catalytic activity of various solid MAO supported .sup.Me.sup.2SB(Cp,I*)HfCl.sub.2 compositions as a function of temperature, in the homopolymerisation of ethylene. FIG. 6 shows the catalytic activity of various solid MAO supported .sup.Me.sup.2SB(Cp,I*)HfCl.sub.2 compositions as a function of time, in the homopolymerisation of ethylene. FIGS. 5 and 6 show that when solid MAO/.sup.Me.sup.2SB(Cp,I*)HfCl.sub.2 was used, the [Al].sub.0/[Zr].sub.0 of 150 demonstrated higher activity than 200:1 or 100:1 over time and temperature of polymerisation of ethylene. This suggests a partial deactivation of the catalyst with high loadings of the hafnium compound.
(55) FIG. 7 shows the catalytic productivity of various solid MAO supported .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 compositions as a function of temperature, in the homopolymerisation of ethylene. FIG. 8 shows the catalytic productivity of various solid MAO supported .sup.Me.sup.2SB(Cp,I*)HfCl.sub.2 compositions as a function of temperature, in the homopolymerisation of ethylene.
(56) In addition to investigating the catalytic properties of the solid MAO supported .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 and .sup.Me.sup.2SB(Cp.sup.Me,I*)HfCl.sub.2 metallocenes, the catalytic properties of the solid MAO supported metallocenes depicted in Schemes 1a and 1b were also investigated. FIGS. 23 to 26 shows the activities and productivities for the slurry phase polymerisation of ethylene using the solid MAO supported metallocenes depicted in Schemes 1a and 1b. The figures show that .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrMe.sub.2 is particularly active.
(57) FIGS. 27 and 28 show the activities for the slurry phase polymerisation of ethylene using .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 and .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 supported on three different supports, namely solid polymethylaluminoxane (sMAO), methylaluminoxane modified layered double hydroxide (LDHMAO) and methylaluminoxane modified silica (ssMAO). These graphs demonstrate that sMAO supported complexes show the highest activities followed by LDHMAO and ssMAO.
(58) FIG. 29 shows the various complex loading on solid polymethylaluminoxane (sMAO) for .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2, demonstrating that as expected, higher activities were obtained with lower loading of complex on the surface.
(59) FIG. 30 shows the effect of varying the amount of triisobutylaluminium (TIBA) scavenger on the catalytic properties of solid MAO supported .sup.Me.sup.2SB(Cp.sup.Me, I*)Zr(CH.sub.2Ph).sub.2 and .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 in the slurry phase polymerisation of ethylene, demonstrating that only a small amount of TIBA is needed to obtain the highest activity.
(60) Table 1 below shows slurry phase ethylene polymerisation data for the solid MAO supported .sup.Me.sup.2SB(Cp.sup.Me, I*)Zr(CH.sub.2Ph).sub.2 and .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 where the polymerisation is conducted on a larger lab scale. The data show that the activity of the catalyst increases with increasing reaction volume, but that an increasing TIBA content gives a negligible improvement in activity and productivity.
(61) TABLE-US-00001 TABLE 1 Activity results (kg.sub.PE g.sub.CAT.sup.1 h.sup.1 bar.sup.1) and productivity (kg.sub.PE g.sub.CAT.sup.1 h.sup.1), for the polymerisation of ethylene in slurry using .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 and .sup.Me.sup.2SB(Cp.sup.Me,I*)Zr(CH.sub.2Ph).sub.2 supported on Solid MAO with [Al].sub.0/[Zr].sub.0 = 200. Polymerisation conditions: 10 mg of catalyst, 250 mL hexane, 2 bar and 80 C. Catalyst TIBA Activity Productivity Catalyst mg mg kg.sub.PE g.sub.CAT.sup.1 h.sup.1 bar.sup.1 kg.sub.PE g.sub.CAT.sup.1 h.sup.1 .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 9.6 150 mg 10014 1.52 .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 9.5 750 mg 9160 1.39 .sup.Me.sup.2SB(Cp.sup.Me,I*)Zr(CH.sub.2Ph).sub.2 9.8 150 mg 10612 1.61 .sup.Me.sup.2SB(Cp.sup.Me,I*)Zr(CH.sub.2Ph).sub.2 9.8 750 mg 11898 1.81
(62) FIG. 31 shows the effect of varying the scavenger on the catalytic properties of solid MAO supported .sup.Me.sup.2SB(Cp.sup.Me,I*)Zr(CH.sub.2Ph).sub.2 and .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 in the slurry phase polymerisation of ethylene, demonstrating that triethylaluminium affords the lowest overall activity. It is believed that fouling occurred when MAO was used in combination with solid MAO supported .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 leading to low activity.
(63) FIG. 32 shows SEM images for polyethylene synthesised using various supported metallocenes. The solid MAO supported metallocenes appear to afford the best polyethylene morphology.
(64) FIG. 38 shows the molecular weight of polyethylene produced from solid MAO supported .sup.Me.sup.2SB(Cp.sup.M,I*)ZrCl.sub.2 as a function of polymerisation temperature.
Example 3Low Molecular Weight Polyethylene Studies
(65) Solid MAO supported .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 (in which the Cp group is unsubstituted, shown below) was selected to investigate the ability of the compositions of the invention to catalyse the polymerisation of ethylene into low molecular weight polyethylene, including polyethylene wax, using hydrogen to control the molecular weight of the growing polymer chains.
(66) ##STR00021##
(67) FIG. 9 shows the productivity (left vertical axis) and polyethylene molecular weight (right vertical axis) of various solid MAO supported .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 compositions as a function of varying hydrogen concentration in ethylene feed stream. The data are tabulated in Table 2 below.
(68) TABLE-US-00002 TABLE 2 Activity results (kg.sub.PE/g.sub.CAT/h) and molecular weight, M.sub.w, (kg/mol) for the polymerization of ethylene in slurry using supported on Solid MAO/.sup.Me2SB(Cp,I*)ZrCl.sub.2 in function of H.sub.2 feeding content. Polymerisation conditions: 0.05 mg of catalyst, 5 mL heptane, 8 bar and 80 C. H.sub.2 [Al].sub.0/ Activity M.sub.w T.sub.el,max (mol %) [Zr].sub.0 kg.sub.PE/g.sub.CAT/h (kg/mol) M.sub.w/M.sub.n ( C.) 0 200 14.2 35 14.2 0.8 200 9.7 29 9.7 1.6 200 5.7 22 5.7 0 150 13.2 50 2.4 111.6 0.8 150 9.6 25 2.7 110.4 1.6 150 4.2 13 3.3 109.8 0 100 12.5 40 4.3 111.6 0.8 100 11.6 25 2.5 110.6 1.6 100 4.8 14 2.7 109.8
(69) FIG. 10 shows the molecular weight (horizontal axis) for the homopolymerisation and polyethylene wax formation using solid MAO/.sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 composition at various [Al].sub.0/[Zr].sub.0 ratios.
(70) FIGS. 9 and 10, and Table 2 show that for the solid MAO/.sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 composition, as the [Al].sub.0/[Zr].sub.0 ratio decreases (meaning an increase in the amount of complex immobilised on the catalyst), there is a decrease in the molecular weight (22000 to 13000 kg/mol) with a constant productivity.
(71) FIG. 11 shows the uptake rate of ethylene for ethylene polymerisation with hydrogen response using Solid MAO/.sup.Me2SB(Cp,I*)ZrCl.sub.2 catalyst using [Al].sub.0/[Zr].sub.0 ratio 100 (left) and 150 (right). FIG. 12 shows molecular weights, M.sub.w, of ethylene polymerisation with hydrogen response using Solid MAO/.sup.Me2SB(Cp,I*)ZrCl.sub.2 catalyst using [Al].sub.0/[Zr].sub.0 ratio of 100 (left) and 150 (right). FIGS. 11 and 12 demonstrate the capability of Solid MAO/.sup.Me2SB(Cp,I*)ZrCl.sub.2 to produce polyethylene wax with [Al].sub.0/[Zr].sub.0 ratio of 100 and 150.
(72) Table 3 below compares the catalytic properties, in the preparation of polyethylene wax, of .sup.Me2SB(Cp,I*)ZrCl.sub.2 and the commercial standard, (.sup.nBuCp).sub.2ZrCl.sub.2, both of which were supported on solid MAO at a [Al].sub.0/[Zr].sub.0 ratio of 200.
(73) TABLE-US-00003 TABLE 3 Activity results (kg.sub.PE/g.sub.CAT/h/bar) and molecular weight (kg/mol) for the polymerisation of ethylene with hydrogen response in slurry using supported on Solid MAO. Activity M.sub.w [Al].sub.0/ Mol ratio Time k.sub.PE/ (kg/ M.sub.w/ Catalyst [Zr].sub.0 H.sub.2:C.sub.2 (h) g.sub.CAT/h/bar mol) M.sub.n (nBuCp).sub.2ZrCl.sub.2 200 0.044:1 2 1.38 3.26 2.5 .sup.Me2SB(Cp,I*)ZrCl.sub.2 200 0.0459:1 1 2.5 2.74 3.8 Polymerisation conditions: 80 C., 8.5 bar, 1000 mL Hexane
(74) The data presented in Table 3 show that Solid MAO/.sup.Me2SB(Cp,I*)ZrCl.sub.2 is two times faster than Solid MAO/(.sup.nBuCp).sub.2ZrCl.sub.2 (commercial standard) when used with the same amount of hydrogen. Solid MAO/.sup.Me2SB(Cp,I*)ZrCl.sub.2 demonstrated particularly low molecular weight, M.sub.w=2743 Kg/mol, which underlines the ability of such compositions to be effective catalysts in the preparation of polyethylene wax.
(75) In addition to the data presented above in respect of solid MAO supported .sup.Me2SB(Cp,I*)ZrCl.sub.2, solid MAO supported .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 (depicted in Scheme 1a) was also selected to investigate the ability of the compositions of the invention to catalyse the polymerisation of ethylene into low molecular weight polyethylene, including polyethylene wax, using hydrogen to control the molecular weight of the growing polymer chains.
(76) Table 4 and FIGS. 33 and 34 show data for the slurry phase polymerisation of ethylene with varying hydrogen content using solid MAO supported .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2.
(77) TABLE-US-00004 TABLE 4 Activity results (kg.sub.PE g.sub.CAT.sup.1 h.sup.1 bar.sup.1) and molecular weight, M.sub.w (kg mol.sup.1), for the polymerisation of ethylene in slurry using .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 supported on Solid MAO with [Al].sub.0/[Zr].sub.0 = 200 in function of H.sub.2 feeding content. Polymerisation conditions: 0.05 mg of catalyst, 5 mL heptane, 8 bar and 80 C. H.sub.2 H.sub.2 Activity M.sub.w Complex (psi) (mol %) kg.sub.PE g.sub.CAT.sup.1 h.sup.1 bar.sup.1 kg mol.sup.1 M.sub.w/M.sub.n .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 0 0 1.30 320 3.0 .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 1 0.8 0.33 23 3.5 .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 2 1.6 0.85 15 2.9
(78) Table 4, as well as FIGS. 33 and 34, shows that when solid MAO supported .sup.Me2SB(Cp.sup.Me,I*)ZrCl.sub.2 was used the uptake rate and molecular weights decrease with increasing hydrogen feeding leading to polyethylene having a molecular weight tending towards that of polyethylene wax.
Example 4Copolymerisation Studies
(79) Solid MAO supported .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 (in which the Cp group is unsubstituted, shown below) was selected to investigate the ability of the compositions of the invention to catalyse the copolymerisation of ethylene and (3-8C)-olefins, in particular 1-hexene.
(80) ##STR00022##
(81) Table 5 below shows the activity results, molecular weight and CEF value for the polymerisation of ethylene and co-polymerisation of ethylene and 1-hexene in slurry using .sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 supported on Solid MAO.
(82) TABLE-US-00005 TABLE 5 Activity results (kg.sub.PE/g.sub.CAT/h), molecular weight (kg/mol) and CEF value for the polymerisation of ethylene and co-polymerisation of ethylene and 1-hexene in slurry using supported on Solid MAO. Activity [Al].sub.0/ [Hexene].sub.feed [Hexene].sub.cop kg.sub.PE/ M.sub.w M.sub.w/ T.sub.el,max [Zr].sub.0 (L) (mol %) g.sub.CAT/h (kg/mol) M.sub.n ( C.) 200 0 0 14.2 73 2.6 111.1 200 125 0.6 20.2 85 2.4 107.2 200 250 1.0 18.5 60 2.1 104.1 150 0 0 15.0 440 3.3 111.7 150 125 0.45 16.6 403 3.0 107.5 150 250 0.8 19.1 363 2.8 105.0 100 0 0 15.9 396 3.0 111.5 100 125 0.5 26.2 417 3.2 107.4 100 250 0.9 28.2 349 3.4 104.6 Polymerisation conditions: 80 C., 8 bar, 5 mL Heptane
(83) FIG. 13 shows the uptake rate of ethylene for copolymerisation of ethylene and 1-hexene; using Solid MAO/.sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 catalyst using [Al].sub.0/[Zr].sub.0 ratio of 100 (left) and 150 (right). FIG. 14 shows the molecular weights, M.sub.w, for copolymerisation of ethylene and 1-hexene using Solid MAO/.sup.Me.sup.2SB(Cp,I*)ZrCl.sub.2 catalyst using [Al].sub.0/[Zr].sub.0 ratio of 100 (left) and 150 (right). FIG. 15 shows the CEF traces for the copolymerisation of ethylene and 1-hexene using Solid MAO/.sup.kh*SB(Cp,I*)ZrCl.sub.2 catalyst using [Al].sub.0/[Zr].sub.0 ratio of 100 (left) and 150 (right). FIGS. 13 to 15 shows that in the copolymerisation of ethylene and 1-hexene, the uptake of 1-hexene increases as the amount of 1-hexene increases. FIGS. 13-15 also demonstrate that the molecular weight of the copolymer does not vary with increasing amounts of 1-hexene, but that the temperature of elution does decrease. This is seen to be the case for both [Al].sub.0/[Zr].sub.0 ratios.
(84) In addition to the data presented above in respect of solid MAO supported .sup.Me2SB(Cp,I*)ZrCl.sub.2, solid MAO supported .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 (depicted in Scheme 1a) was also selected to investigate the ability of the compositions of the invention to catalyse the copolymerisation of ethylene and (3-8C)-olefins, in particular 1-hexene.
(85) Table 6 and FIGS. 35 to 37 show data for the slurry phase copolymerisation of ethylene and 1-hexene using solid MAO supported .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2.
(86) TABLE-US-00006 TABLE 6 Activity results (kg.sub.PE g.sub.CAT.sup.1 h.sup.1 bar.sup.1), molecular weight, M.sub.w (kg mol.sup.1), and CEF value for the polymerisation of ethylene and co-polymerisation of ethylene and 1-hexene in slurry using .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 supported on Solid MAO with [Al].sub.0/[Zr].sub.0 = 200. Polymerisation conditions: 0.05 mg of catalyst, 5 mL heptane, 8 bar and 80 C. [Hexene].sub.feed Activity M.sub.w T.sub.el,max Complex L kg.sub.PE g.sub.CAT.sup.1 h.sup.1 bar.sup.1 kg mol.sup.1 M.sub.w/M.sub.n C. .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 0 1.51 371 3.0 113.1 .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 125 1.58 294 2.4 108.1 .sup.Me.sup.2SB(Cp.sup.Me,I*)ZrCl.sub.2 250 2.06 289 2.5 105.1
(87) FIGS. 35 and 36 shows that when Solid MAO supported .sup.Me2SB(Cp.sup.Me,I*)ZrCl.sub.2 was used the uptake rate increase (up to deactivation with 250 L) and molecular weights stays similar with increasing comonomer (1-hexene) feeding. Similarly, FIG. 37 shows the CEF traces related and that increased 1-hexene feeding led to decrease in the elution temperature highlighting an increase in incorporation. Table 6 corroborates these data.
(88) While specific embodiments of the invention have been described herein for the purpose of reference and illustration, various modifications will be apparent to a person skilled in the art without departing from the scope of the invention as defined by the appended claims.
