U.S. patent application number 09/905331 was filed with the patent office on 2001-11-22 for haloaryl containing group 13 substituents on bridged metallocene polyolefin catalysts.
Invention is credited to Holtcamp, Matthew W..
Application Number | 20010044509 09/905331 |
Document ID | / |
Family ID | 22346446 |
Filed Date | 2001-11-22 |
United States Patent
Application |
20010044509 |
Kind Code |
A1 |
Holtcamp, Matthew W. |
November 22, 2001 |
Haloaryl containing group 13 substituents on bridged metallocene
polyolefin catalysts
Abstract
A process for the preparation of polyolefins from one or more
olefinic monomers is described in which the olefins are combined
with a catalyst complex derived from a catalyst compound having a
bis-haloaryl-Group 13 element substituted Group 13-15
atom-containing bridging element, and a co-catalyst activator a
tri-n-alkyl aluminum compound or aluminoxy derivative thereof The
process is particularly useful with bisarylboron substituted
silicon-bridged metallocenes under gas phase, slurry, solution or
supercritical high pressure coordination polymerization conditions
for polyolefins derived from olefinic monomers selected from the
group consisting of ethylene, .alpha.-olefins, cyclic olefins,
non-conjugated diolefins, vinyl aromatic olefins, and geminally
disubstituted olefins.
Inventors: |
Holtcamp, Matthew W.;
(Huffman, TX) |
Correspondence
Address: |
Univation Technologies L.L.C.
Suite 1950
5555 San Felipe
Houston
TX
77056
US
|
Family ID: |
22346446 |
Appl. No.: |
09/905331 |
Filed: |
July 13, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09905331 |
Jul 13, 2001 |
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09451833 |
Nov 30, 1999 |
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6291610 |
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60112900 |
Dec 18, 1998 |
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Current U.S.
Class: |
526/127 ;
502/152; 526/160; 526/308; 526/335; 526/346; 526/348.2; 526/348.3;
526/348.5; 526/348.6; 526/901; 526/943 |
Current CPC
Class: |
C08F 4/65912 20130101;
C08F 4/65916 20130101; Y10S 526/943 20130101; Y02P 20/544 20151101;
C08F 10/00 20130101; Y02P 20/54 20151101; C08F 210/16 20130101;
C08F 10/00 20130101; C08F 4/65927 20130101; C08F 210/16 20130101;
C08F 210/14 20130101; C08F 2500/02 20130101; C08F 2500/03
20130101 |
Class at
Publication: |
526/127 ;
526/160; 526/943; 526/901; 502/152; 526/348.2; 526/348.3;
526/348.5; 526/348.6; 526/308; 526/335; 526/346 |
International
Class: |
C08F 004/44 |
Claims
I claim:
1. A transition metal organometallic catalyst compound suitable for
the polymerization of olefins comprising the chemical reaction
product of: (i) a metallocene compound having a Group 13-15
bridging element substituted with a Group 13 moiety containing two
halogenated aromatic groups, and (ii) an alkyl aluminum compound or
aluminoxy derivative thereof.
2. The transition metal organometallic catalyst compound of claim 1
having the formula:
(L.sup.A)(E.sup.1RE.sup.2(ArX).sub.2)(L.sup.B)L.sup.C.sub.iM- AB
where, L.sup.A is a substituted cyclopentadienyl or
heterocyclopentadienyl ancillary ligand .pi.-bonded to M; L.sup.B
is a member of the class of ancillary ligands defined for L.sup.A,
or is J, a heteroatom ancillary ligand bonded to M; E.sup.1 is a
Group 13-15 atom-containing linking group covalently bonded to
L.sup.A and L.sup.B; R is a monovalent group covalently bonded to
E.sup.1; E.sup.2(ArX) is a Group 13 moiety containing two
halogenated aromatic groups, said moiety covalently bonded to
E.sup.1; L.sup.C.sub.i is one or more optional, neutral
non-oxidizing ligand having a dative bond to M (i equals 0 to 3); M
is a Group 3-6 transition metal; and, A and B are independently
monoanionic labile ligands, each having a .sigma.-bond to M,
optionally bridged to each other or L.sup.A or L.sup.B, which can
be broken for abstraction purposes by a suitable activator and into
which a polymerizable monomer or macromonomer can insert for
coordination polymerization.
3. The catalyst compound of claim 2 wherein L.sup.B is a member of
the class of ancillary ligands defined for L.sup.A and M is a Group
4 metal.
4. The catalyst compound of claim 2 wherein L.sup.B is J, a Group
15 or 16 heteroatom ancillary ligand bonded to M and M is a Group 3
to 5 metal.
5. The catalyst compound of claim 2 wherein E.sup.1 is silicon and
E.sup.2 is boron.
6. The catalyst compound of claim 2 wherein E.sup.1 is carbon and
E.sup.2 is boron.
7. A process for the preparation of polyolefins from one or more
olefinic monomers comprising combining said olefins with a catalyst
complex derived from: (i) a metallocene compound having a silicon
bridging element substituted with a boron moiety containing two
halogenated aromatic groups, and (ii) an alkyl aluminum compound or
aluminoxy derivative thereof; and optionally, (iii) a support
material.
8. The process of claim 7 wherein said transition metal
organometallic catalyst compound is a metallocene compound having
the formula:
(L.sup.A)(E.sup.1RE.sup.2(ArX).sub.2)(L.sup.B)L.sup.C.sub.iMAB
where, L.sup.A is a substituted cyclopentadienyl or
heterocyclopentadienyl ancillary ligand .pi.-bonded to M; L.sup.B
is a member of the class of ancillary ligands defined for L.sup.A,
or is J, a heteroatom ancillary ligand bonded to M; E.sup.1 is a
Group 13-15 atom-containing linking group covalently bonded to
L.sup.A and L.sup.B; R is a monovalent group covalently bonded to
E.sup.1; E.sup.2(ArX) is a Group 13 moiety containing two
halogenated aromatic groups, said moiety covalently bonded to
E.sup.1; L.sup.C.sub.i is one or more optional, neutral
non-oxidizing ligand having a dative bond to M (i equals 0 to 3); M
is a Group 3-6 transition metal; and, A and B are independently
monoanionic labile ligands, each having a .sigma.-bond to M,
optionally bridged to each other or L.sup.A or L.sup.B, which can
be broken for abstraction purposes by a suitable activator and into
which a polymerizable monomer or macromonomer can insert for
coordination polymerization.
9. The process according to claim 7 or 8 wherein said combining is
done under gas phase, slurry, solution or supercritical high
pressure coordination polymerization conditions.
10. The process according to claim 9 wherein conditions are slurry
conditions and said olefinic monomers are one or more selected from
the group consisting of ethylene, C.sub.3-C.sub.10.alpha.-olefins,
C.sub.5-C.sub.20 cyclic olefins, C.sub.5-C.sub.20 non-conjugated
diolefins, C.sub.7-C.sub.20 vinyl aromatic olefins, and
C.sub.4-C.sub.20 geminally disubstituted olefins.
11. The process according to claim 9 wherein conditions are
solution polymerization conditions and said olefinic monomers are
one or more selected from the group consisting of ethylene,
C.sub.3-C.sub.10 .alpha.-olefins, C.sub.5-C.sub.20 cyclic olefins,
C.sub.5-C.sub.20 non-conjugated diolefins, C.sub.7-C.sub.20 vinyl
aromatic olefins, and C.sub.4-C.sub.20 geminally disubstituted
olefins.
12. The process according to claim 9 wherein conditions are gas
phase polymerization conditions and said olefinic monomers are one
or more selected from the group consisting of ethylene and
C.sub.3-C.sub.10 .alpha.-olefins.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This patent application claims priority from Provisional
U.S. patent application Ser. No. 60/112,900, filed Dec. 18, 1998,
which is herein fully incorporated by reference.
TECHNICAL FIELD
[0002] This invention relates to a process for coordination
polymerization of olefins using metallocenes having pendant, boron
based Lewis acid groups.
BACKGROUND ART
[0003] Boron based Lewis acids having fluorinated aryl substituents
are known to be capable of activating transition metal compounds
into olefin polymerization catalysts. Trisperfluorophenylborane is
taught in EP 0 520 732 to be capable of abstracting a ligand for
certain cyclopentadienyl derivatives of transition metals while
providing a stabilizing, compatible noncoordinating anion. The term
"noncoordinating anion" is now accepted terminology in the field of
olefin polymerization, both by coordination or insertion
polymerization and carbocationic polymerization. See, for example,
EP 0 277 004, U.S. Pat. No. 5,198,401, and Baird, Michael C., et
al, J. Am. Chem. Soc. 1994, 116, 6435-6436, and U.S. Pat. No.
5,668,324. The noncoordinating anions are described to function as
electronic stabilizing cocatalysts, or counterions, for cationic
metallocene complexes which are active for olefin polymerization.
The term noncoordinating anion as used here applies both to truly
noncoordinating anions and coordinating anions that are at most
weakly coordinated to the cationic complex so as to be labile to
replacement by olefinically or acetylenically unsaturated monomers
at the insertion site.
[0004] Organoaluminum compounds are known to be useful with
metallocene based transition metal cationic catalysts, as
cocatalyst activators, or for those stabilized with noncoordinating
anions, for both catalyst poison inhibition and alkylation of
metallocene dihalide compounds, see WO 91/14713 and EP 0 500 944.
See also WO 93/14132 where alumoxane compounds are said to be
useful for inhibiting catalyst poisons in the presence of cationic,
cyclopentadienyl Group 4 complexes activated by
tris(perfluorophenyl)boron.
[0005] Certain metallocene compounds having pendant, boron based
Lewis acid groups are described by R. E. v. H. Spence and W. E.
Piers in "Toward One-Component Group 4 Homogenous Ziegler-Natta
Olefin Polymerization Catalysts: Hydroboration of Zirconium
bisalkyl with Pendant 2-Propenyl Groups Using
[(C.sub.6F.sub.5).sub.2BH].sub.2", Organometallics 1995, 14,
4617-4624. As indicated in the title, compounds having boron based
Lewis acids having fluorinated aryl substituents linked to
cyclopentadienyl ring carbon atoms via hydroboration of propenyl
groups that are pendant to cyclopentadienyl ligands are disclosed.
It is suggested that these compounds will have utility as
zwitterionic, self-activating catalysts. See also the zwitterionic
catalysts of U.S. Pat. No. 5,792,819 where pendant, boron based
Lewis acid groups are attached to a Group 4 metal center.
[0006] The synthesis of Group 13-based compounds derived from
trisperfluorophenylborane are described in EP 0 694 548. These
compounds are said to be represented by the formula
M(C.sub.6F.sub.5).sub.3 and are prepared by reacting the
trisperfluorophenylborane with dialkyl or trialkyl Group 13-based
compounds at a molar ratio of "basically 1:1" so as to avoid mixed
products, those including the type represented by the formula
M(C.sub.6F.sub.5).sub.nR.sub.3--n, where n=1 or 2. Utility for the
trisaryl aluminum compounds in Ziegler-Natta olefin polymerization
is suggested.
BRIEF SUMMARY OF THE INVENTION:
[0007] The invention comprises a process for the preparation of
polyolefins from one or more olefinic monomers comprising combining
said olefins with a novel catalyst complex derived from: (i) a
metallocene catalyst compound having a Group 13-15 bridging element
substituted with a Group 13 moiety containing two halogenated
aromatic groups, and (ii) an alkyl aluminum compound or aluminoxy
derivative thereof. In the invention, the pendant, Lewis acidic
Group 13 moiety is bonded to the metallocene through the bridging
Group 13-15 atom that is also covalently bonded to at least one
cyclopentadienyl ring atom of a metal ligand and to a second
ancillary metal ligand that may be another, same or different,
cyclopentadienyl ring ligand or a heteroatom ligand of the same
metal center. Increased activities, over those with similar
metallocenes not having the pendant boron groups and similarly
activated with alumoxane compounds, have been observed with the
invention catalysts.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 illustrates an example of the invention where the
compound
CH.sub.3((C.sub.6F.sub.5).sub.2BCH.sub.2CH.sub.2)Si(Ind).sub.2ZrCl.sub.2,
where "Ind" refers to an indenyl ligand, is activated with
methylalumoxane ("MAO") and used to prepare an ethylene-hexene
copolymer.
DETAILED DESCRIPTION OF THE INVENTION
[0009] The invention summarized above can be more specifically
represented as an olefin polymerization process using a novel
catalyst composition derived from a metallocene compound having the
formula:
(L.sup.A)(E.sup.1RE.sup.2(ArX).sub.2)(L.sup.B)L.sup.C.sub.iMAB
[0010] where L.sup.A is a substituted or unsubstituted
cyclopentadienyl or heterocyclopentadienyl ancillary ligand
.pi.-bonded to M;L.sup.B is a member of the class of ancillary
ligands defined for L.sup.A, or is J, a heteroatom ancillary ligand
bonded to M; E.sup.1 is a Group 13-15 atom-containing linking group
covalently bonded to L.sup.A and L.sup.B, said Group 13-15 atom
preferably being, Si, C, Ge, N or P; R is a monovalent group
covalently bonded to E.sup.1; E.sup.2(ArX) is a Group 13,
preferably B or A1, moiety containing two halogenated aromatic
groups, said moiety covalently bonded to E.sup.1; L.sup.C.sub.i is
one or more optional, neutral non-oxidizing ligand having a dative
bond to M (i equals 0 to 3); M is a Group 3-6 transition metal;
and, A and B are independently monoanionic labile ligands, each
having a .sigma.-bond to M, optionally bridged to each other or
L.sup.A or L.sup.B, which can be broken or replaced for abstraction
purposes by a suitable activator and into which a polymerizable
monomer or macromonomer can insert for coordination
polymerization.
[0011] The substituted or unsubstituted cyclopentadienyl or
heterocyclopentadienyl ancillary ligands represented by L.sup.A are
generally characterized by a 5-member aromatic ring consisting
essentially of carbon atoms, which may contain as substituents for
one or more ring hydrogen atoms, hydrocarbyl groups, preferably
C.sub.1 to C.sub.30, where one or more carbons may be replaced with
a Group 13-16 heteroatom, including one or more pendant and/or
fused substituted or unsubstituted rings, ring optional
substituents typically consisting of C.sub.1 to C.sub.10
hydrocarbyl or hydrocarbylsilyl groups. As is known in the art, the
5-member aromatic ring may have a ring carbon atom replaced with a
Group 13-15 heteroatom and still be capable of .pi.-bonding to M.
Similarly, the skilled artisan will recognize that all of indenyl,
fluorenyl, azulenyl, and heterocyclic analogs thereof, are suitable
substituted derivatives of 5-member aromatic rings. Typically such
ligands are known in the art for organometallic metallocene
compounds, and accordingly methods for the synthesis of
metallocenes containing such ligands are known. See, for example,
U.S. Pat. Nos. 5,278,264, 5,304,614, 5,324,800, 5,324,801,
5,502,124 and WO 95/04087, each of which is incorporated by
reference for purposes of U.S. patent practice.
[0012] The heteroatom ancillary ligand J is typically a Group 15 or
16 element, where if group 15 is generally substituted with a
C.sub.1 to C.sub.30 hydrocarbyl group as defined for the
substituents for L.sup.A. Compounds having a J ligand are typically
known as monocyclopentadienyl metallocene compounds and the
substantial art relating thereto is instructive as to selection and
synthesis of compounds containing such. See, for example U.S. Pat.
Nos. 5,055,438, 5,264,505, 5,625,016, 5,635,573 and 5,763,556.
[0013] For the bridging group E.sup.1RE.sup.2(ArX).sub.2, R is
typically a C.sub.1 to C.sub.10 hydrocarbyl group covalently
linking the E.sup.2 atom to the E.sup.1 atom. One or more carbon
atoms in the linking chain between the E.sup.2 atom and the E.sup.1
atom may be substituted with a short chain, e.g., C.sub.1 to
C.sub.6, hydrocarbyl or hydrocarbylsilyl group as well. "ArX"
refers to a halogenated aromatic group, preferably a C.sub.6 or a
C.sub.5N aromatic group, or derivative thereof, having at least
three halogen atoms, preferably fluorine, replacing aromatic ring
hydrogen atoms. The halogenated aromatic groups may be derived from
any aromatic ring, ring assembly, or fused ring ligand suitable as
compatible ligands for noncoordinating anions as that term is
recognized in the olefin polymerization art. Typical examples
include phenyl, napthyl, anthracyl and biphenyl rings. See, e.g.,
U.S. Pat. No. 5,198,401, WO 97/29845, and the co-pending U.S.
patent application Ser. No. 09/191922 filed Nov. 13, 1998.
[0014] The A and B groups are monoanionic labile ligands are
typically those hydride, alkyl or halogen ligands known and used
for the metallocene catalysts of the prior art. Typical examples
include hydride, methyl, ethyl, benzyl, methyl trimethylsilyl, and
chlorine. Such alkyl ligands can be generically described as
C.sub.1 to C.sub.20 hydrocarbyl substituents where the carbon atom
attached to the metal center is a primary carbon atom
(--CH.sub.2R').
[0015] Silicon-bridged metallocene compounds suitable for the
preparation of linear polyethylene or ethylene-containing
copolymers (where copolymer means comprising at least two different
monomers) are essentially any of those known in the art, see again
EP-A-277,004, WO-A-92/00333 and U.S. Pat. Nos. 5,001,205,
5,198,401, 5,324,800, 5,308,816, and 5,304,614 for specific
listings. Selection of silicon-bridged metallocene compounds for
use to make isotactic or syndiotactic polypropylene, and their
syntheses, are well-known in the art, specific reference may be
made to both patent literature and academic, see for example
Journal of organometallic Chemistry 369, 359-370 (1989). Typically
those catalysts are bridged asymmetric or bridged chiral
metallocenes. See, for example, U.S. Pat. No. 4,892,851, U.S. Pat.
No. 5,017,714, U.S. Pat. No. 5,296,434, U.S. Pat. No. 5,278,264,
WO-A-(PCT/US92/10066) WO-A-93/19103, EP-A2-0 577 581, EP-A1-0 578
838, and academic literature "The Influence of Aromatic
Substituents on the Polymerization Behavior of Bridged Zirconocene
Catalysts", Spaleck, W., et al, Organometallics 1994, 13, 954-963,
and "ansa-Zirconocene Polymerization Catalysts with Annelated Ring
Ligands-Effects on Catalytic Activity and Polymer Chain Lengths",
Brinzinger, H., et al, Organometallics 1994, 13, 964-970, and
documents referred to therein.
[0016] Exemplary compounds according to the invention include:
(bispentafluorophenyboryl-ethyl)(methyl)silyl(bisindenyl)zirconiumdichlor-
ide or dimethyl,
(bispentafluorophenyboryl-ethyl)(methyl)methene(fluorenyl- )
(cyclopentadienyl) zirconium dichloride or dimethyl,
(bispentafluorophenyboryl-ethyl)(phenyl)silyl
(fluorenyl)(cyclopentadieny- l) zirconium dichloride or dimethyl,
(bispentafluorophenyboryl-ethyl)(phen- yl)silyl(indenyl)
(fluorenyl) zirconium dichloride or dimethyl,
(bispentafluorophenyboryl-propyl) (phenyl) silyl(bisindenyl)
zirconiumdichloride or dimethyl,
(bispenta-fluorophenyboryl-ethyl)(hydryl- )ethane (bisindenyl)
zirconium dichloride or dimethyl,
(bispentafluorophenyborylethyl)(methyl)silyl(bisindenyl)hafiiiumdichlorid-
e or dimethyl,
(bispentafluorophenylboryl-ethyl)(methyl)methene(fluorenyl)
(cyclopenta-dienyl) hafnium dichloride or dimethyl,
(bispentafluorophenyboryl-ethyl)(phenyl)silyl
(fluorenyl)(cyclopentadieny- l) hafnium dichloride or dimethyl,
(bispentafluorophenyboryl-ethyl)(phenyl- )silyl(indenyl)
(fluorenyl) hafnium dichloride or dimethyl,
(bispentafluorophenyboryl-propyl) (phenyl) silyl(bisindenyl)
hafniumdichloride or dimethyl,
(bispenta-fluorophenyborylethyl)(hydryl)et- hane (bisindenyl)
hafnium dichloride or dimethyl, (bispentafluorophenybory- l-ethyl)
(propyl)silyl (fluorenyl) (n-dodecylamido)titaniumdichloride or
dimethyl, and
(bispentafluorophenyboryl-ethyl)(methyl)silyl(tetramethylcy-
clopentadienyl)(tert-butylamido)titaniumdichloride or dimethyl.
Analogs of the titanium compounds can be prepared with trivalent
metals of Groups 3, 5 and 6 within the skill in the art.
[0017] Alkylalumoxanes and modified alkylalumoxanes are suitable as
catalyst activators, particularly for the invention metal compounds
comprising halide ligands. The alumoxane component useful as
catalyst activator typically is an oligomeric aluminum compound
represented by the general formula (R"-A1-O).sub.n, which is a
cyclic compound, or R"(R"-A1-O).sub.nA1R".sub.2, which is a linear
compound. In the general alumoxane formula R" is independently a
C.sub.1 to C.sub.10 alkyl radical, for example, methyl, ethyl,
propyl, butyl or pentyl and "n" is an integer from 1 to about 50.
Most preferably, R" is methyl and "n" is at least 4. Alumoxanes can
be prepared by various procedures known in the art. For example, an
aluminum alkyl may be treated with water dissolved in an inert
organic solvent, or it may be contacted with a hydrated salt, such
as hydrated copper sulfate suspended in an inert organic solvent,
to yield an alumoxane. Generally, however prepared, the reaction of
an aluminum alkyl with a limited amount of water yields a mixture
of the linear and cyclic species of the alumoxane. Methylalumoxane
and modified methylalumoxanes are preferred. For further
descriptions see, U.S. Pat. Nos. 4,665,208, 4,952,540, 5,041,584,
5,091,352, 5,206,199, 5,204,419, 4,874,734, 4,924,018, 4,908,463,
4,968,827, 5,329,032, 5,248,801, 5,235,081, 5,157,137, 5,103,031
and EP 0 561 476 A1, EP 0 279 586 B1, EP 0 516 476 A, EP 0 594 218
A1 and WO 94/10180, each being incorporated by reference for
purposes of U.S. patent practice.
[0018] Organoaluminum compounds are also suitable catalyst
activators for the organometallic catalyst compounds of the
invention. These can be represented by the formulae Al(R.sup.1)3,
wherein R.sup.1 is independently a hydride or C.sub.1 to C.sub.30
hydrocarbyl including aliphatic, alicyclic or aromatic hydrocarbon
radicals. Preferred examples include trimethylaluminum,
triethylaluminum, tri-n-propylaluminum, triisobutylaluminum,
tri-n-butylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum,
tri-n-dodecylaluminum, tri-n-eicosylaluminum, and those aluminum
compounds having mixed substitutents including those generically
described above.
[0019] The catalysts according to the invention may be supported
for use in gas phase, bulk, slurry polymerization processes, or
otherwise as needed. Numerous methods of support are known in the
art for copolymerization processes for olefins, particularly for
catalysts activated by alumoxanes, any is suitable for the
invention process in its broadest scope. See, for example, U.S.
Pat. Nos. 5,057,475 and 5,227,440. An example of supported ionic
catalysts appears in WO 94/03056. A bulk, or slurry, process
utilizing supported, bis-cyclopentadienyl Group 4 metallocenes
activated with alumoxane co-catalysts is described as suitable for
ethylene-propylene rubber in U.S. Pat. Nos. 5,001,205 and
5,229,478, these processes will additionally be suitable with the
catalyst systems of this application. Both inorganic oxide and
polymeric supports may be utilized in accordance with the knowledge
in the field. See U.S. Pat. Nos. 5,422,325, 5,498,582, and
5,466,649. Each of the foregoing documents is incorporated by
reference for purposes of U.S. patent practice.
[0020] In preferred embodiments of the process for this invention,
the catalyst system is employed in liquid phase (solution, slurry,
suspension, bulk phase or combinations thereof), in high pressure
liquid or supercritical fluid phase, or in gas phase. Each of these
processes may be employed in singular, parallel or series reactors.
The liquid processes comprise contacting the olefin monomers with
the above described catalyst system in a suitable diluent or
solvent and allowing said monomers to react for a sufficient time
to produce the invention copolymers. Hydrocarbyl solvents are
suitable, both aliphatic and aromatic, hexane and toluene are
preferred. Bulk and slurry processes are typically done by
contacting the catalysts with a slurry of liquid monomer, the
catalyst system being supported. Gas phase processes similarly use
a supported catalyst and are conducted in any manner known to be
suitable for ethylene homopolymers or copolymers prepared by
coordination polymerization. Illustrative examples may be found in
U.S. Pat. Nos. 4,543,399, 4,588,790, 5,028,670, 5,382,638,
5352,749, 5,436,304, 5,453,471, and 5,463,999, and WO 95/07942.
Each is incorporated by reference for purposes of U.S. patent
practice.
[0021] When using the catalysts of the invention, particularly when
immobilized on a support, the total catalyst system may
additionally comprise one or more scavenging compounds in amounts
effective for the scavenging finction. The term "scavenging" as
used in this application means effective for removing polar
impurities from the reaction environment. Impurities can be
inadvertently introduced with any of the polymerization reaction
components, particularly with solvent, monomer and catalyst feed,
and adversely affect catalyst activity and stability. It can result
in decreasing or even elimination of catalytic activity,
particularly when ionizing anion pre-cursors activate the catalyst
system. The polar impurities, or catalyst poisons include water,
oxygen, metal impurities, etc. Preferably steps are taken before
provision of such into the reaction vessel, for example by chemical
treatment or careful separation techniques after or during the
synthesis or preparation of the various components, but some minor
amounts of scavenging compound will still normally be used in the
polymerization process itself.
[0022] Typically the scavenging compound will be an excess of the
alkylated Lewis acids needed for initiation, as described above, or
will be additional known organometallic compounds such as the
Group-13 organometallic compounds of U.S. Pat. Nos. 5,153,157,
5,241,025 and WO-A-91/09882, WO-A-94/03506, WO-A-93/14132, and that
of WO 95/07941. Exemplary compounds include triethyl aluminum,
triethyl borane, triisobutyl aluminum, methylalumoxane, isobutyl
aluminumoxane, and tri-n-octyl aluminum. Those scavenging compounds
having bulky or C.sub.6-C.sub.20 linear hydrocarbyl substituents
covalently bound to the metal or metalloid center being preferred
to minimize adverse interaction with the active catalyst. Examples
include triethylaluminum, but more preferably, bulky compounds such
as triisobutylaluminum, triisoprenylaluminum, and long-chain linear
alkyl-substituted aluminum compounds, such as tri-n-hexylaluminum,
tri-n-octylaluminum, tri-n-dodecylaluminum and the higher carbon
number tri-n-alkyl aluminum compounds. When alumoxane is used as an
activator, any excess over the amount needed to activate the
catalysts present will act as scavenger compounds and additional
scavenging compounds may not be necessary. Alumoxanes also may be
used in scavenging amounts with other means of activation, e.g.,
methylalumoxane and triisobutyl-aluminoxane. The amount of
scavenging agent to be used with the catalyst compounds of the
invention is minimized during polymerization reactions to that
amount effective to enhance activity and avoided altogether if the
feeds and polymerization medium can be sufficiently free of
adventitious impurities, or if the alumoxane or alkyl aluminum
compounds are present in sufficient excess over that needed to
activate the catalysts.
[0023] The catalyst complexes of the invention are useful in
polymerization of unsaturated monomers conventionally known to be
polymerizable under coordination polymerization using metallocenes.
Such conditions are well known and include solution polymerization,
slurry polymerization, gas-phase polymerization, and high pressure
polymerization. The catalyst of the invention may be supported
(preferably as described above) and as such will be particularly
useful in the known operating modes employing fixed-bed,
moving-bed, fluid-bed, slurry or solution processes conducted in
single, series or parallel reactors. Pre-polymerization of
supported catalyst of the invention may also be used for further
control of polymer particle morphology in typical slurry or gas
phase reaction processes in accordance with conventional
teachings.
[0024] In alternative embodiments of olefin polymerization methods
for this invention, the catalyst system is employed in liquid phase
(solution, slurry, suspension, bulk phase or combinations thereof),
in high pressure liquid or supercritical fluid phase, or in gas
phase polymerization processes. Each of these processes may also be
employed in singular, parallel or series reactors. The liquid
processes comprise contacting olefin monomers with the above
described catalyst system in a suitable diluent or solvent and
allowing said monomers to react for a sufficient time to produce
the invention copolymers. Hydrocarbyl solvents are suitable, both
aliphatic and aromatic, hexane and toluene are preferred. Bulk and
slurry processes are typically done by contacting the catalysts
with a slurry of liquid monomer, the catalyst system being
supported. Gas phase processes typically use a supported catalyst
and are conducted in any manner known to be suitable for ethylene
homopolymers or copolymers prepared by coordination polymerization.
Illustrative examples may be found in U.S. Pat. Nos. 4,543,399,
4,588,790, 5,028,670, 5,382,638, 5,352,749, 5,436,304, 5,453,471,
and 5,463,999, and WO 95/07942. Each is incorporated by reference
for purposes of U.S. patent practice.
[0025] Generally speaking the polymerization reaction temperature
can vary from about 40.degree. C. to about 250.degree. C.
Preferably the polymerization reaction temperature will be from
60.degree. C. to 220.degree., more preferably below 200.degree. C.
The pressure can vary from about 1 mm Hg to 2500 bar, preferably
from 0.1 bar to 1600 bar, most preferably from 1.0 to 500 bar.
[0026] Linear polyethylene, including high and ultra-high molecular
weight polyethylenes, including both homo- and copolymers with
other alpha-olefin monomers, alpha-olefinic and/or non-conjugated
diolefins, for example, C.sub.3-C.sub.20 olefins, diolefins or
cyclic olefins, are produced by adding ethylene, and optionally one
or more of the other monomers, to a reaction vessel under low
pressure (typically <50 bar), at a typical temperature of
40-250.degree. C. with the invention catalyst that has been
slurried with a solvent, such as hexane or toluene. Heat of
polymerization is typically removed by cooling. Gas phase
polymerization can be conducted, for example, in a continuous fluid
bed gas-phase reactor operated at 2000-3000 kPa and 60-160.degree.
C., using hydrogen as a reaction modifier (100-200 PPM),
C.sub.4-C.sub.8 comonomer feedstream (0.5-1.2 mol %), and C.sub.2
feedstream (25-35 mol %). See, U.S. Pat. Nos. 4,543,399, 4,588,790,
5,028,670 and 5,405,922 and 5,462,999, which are incorporated by
reference for purposes of U.S. patent practice.
[0027] Ethylene-.alpha.-olefin (including ethylene-cyclic olefin
and ethylene-.alpha.-olefin-diolefin) elastomers of high molecular
weight and low crystallinity can be prepared utilizing the
catalysts of the invention under traditional solution
polymerization processes or by introducing ethylene gas into a
slurry utilizing the .alpha.-olefin or cyclic olefin or mixture
thereof with other monomers, polymerizable and not, as a
polymerization diluent in which the invention catalyst is
suspended. Typical ethylene pressures will be between 10 and 1000
psig (69-6895 kPa) and the polymerization diluent temperature will
typically be between 40 and 160.degree. C. The process can be
carried out in a stirred tank reactor, or more than one operated in
series or parallel. See the general disclosure of U.S. Pat. No.
5,001,205 for general process conditions. See also, international
application WO 96/33227 and WO 97/22639. All documents are
incorporated by reference for description of polymerization
processes, metallocene selection and useful scavenging
compounds.
[0028] Other olefinically unsaturated monomers besides those
specifically described above may be polymerized using the catalysts
according to the invention, for example, styrene, alkyl-substituted
styrenes, isobutylene, ethylidene norbornene, norbomadiene,
dicyclopentadiene, and other olefinically-unsaturated monomers,
including other cyclic olefins, such as cyclopentene, norbornene,
and alkyl-substituted norbornenes. Additionally, alpha-olefinic
macromonomers of up to 1000 mer units, or more, may also be
incorporated by copolymerization.
[0029] The catalyst compositions of the invention can be used as
described above individually for coordination polymerization or can
be mixed to prepare polymer blends with other known olefin
polymerization catalyst compounds. By selection of monomers, blends
of coordination catalyst compounds, polymer blends can be prepared
under polymerization conditions analogous to those using individual
catalyst compositions. Polymers having increased MWD for improved
processing and other traditional benefits available from polymers
made with mixed catalyst systems can thus be achieved.
[0030] The formation of blended polymers can be achieved ex situ
through mechanical blending or in situ through the use of a mixed
catalyst system. It is generally believed that in situ blending
provides a more homogeneous product and allows the blend to be
produced in one step. The use of mixed catalyst systems for in situ
blending involves combining more than one catalyst in the same
reactor to simultaneously produce multiple distinct polymer
products. This method requires additional catalyst synthesis and
the various catalyst components must be matched for their
activities, the polymer products they generate at specific
conditions, and their response to changes in polymerization
conditions.
[0031] The following examples are presented to illustrate the
foregoing discussion. All parts, proportions and percentages are by
weight unless otherwise indicated. All examples were carried out in
dry, oxygen-free environments and solvents. Although the examples
may be directed to certain embodiments of the present invention,
they are not to be viewed as limiting the invention in any specific
respect. In these examples certain abbreviations are used to
facilitate the description. These include standard chemical
abbreviations for the elements and certain commonly accepted
abbreviations, such as: Me=methyl, THF, or thf, =tetrahydrofuran,
and Cp*, permethylated cyclopentadienyl metal ligand.
[0032] All molecular weights are weight average molecular weight
unless otherwise noted. Molecular weights (weight average molecular
weight (Mw) and number average molecular weight (Mn) were measured
by Gel Permeation Chromatography, unless otherwise noted, using a
Waters 150 Gel Permeation Chromatograph equipped with a
differential refractive index detector and calibrated using
polystyrene standards. Samples were run in either THF (45.degree.
C.) or in 1,2,4-trichlorobenzene (145.degree. C.) depending upon
the sample's solubility using three Shodex GPC AT-80 M/S columns in
series. This general technique is discussed in "Liquid
Chromatography of Polymers and Related Materials III" J. Cazes Ed.,
Marcel Decker, 1981, page 207, which is incorporated by reference
for purposes of U.S. patent practice herein. No corrections for
column spreading were employed; however, data on generally accepted
standards, e.g. National Bureau of Standards Polyethylene 1475,
demonstrated a precision with 0.1 units for Mw/Mn which was
calculated from elution times. The numerical analyses were
performed using Expert Ease software available from Waters
Corporation.
EXAMPLES:
[0033] All reactions were performed under nitrogen in dryboxes or
connected to Schlenk lines unless stated otherwise. Lithium
tetramethylcyclopentadienyl was purchased from Strem and used as
received. 30 wt % methylalumoxane in toluene was purchased from
Albermarle and used as received. Triethylaluminum was purchased
from Akzo Nobel and used as received. HB(C.sub.6F5).sub.2 was
prepared using the method described by Piers et al. (Angew. Chem.
Int. Ed. Engl. 1995, 34, 809). Zr(NMe.sub.2).sub.4 was prepared by
the method described by Jordan et al. (Organometallics 1995, 14,
5.)
[0034] Synthesis of Metallocenes
[0035] 1. CH.sub.3(CH.sub.2=CH)Si(CP*H).sub.2.
[0036] Lithium tetramethylcyclopentadienyl (Cp*) (20 grams) was
combined with dichloromethylvinylsilane (11 grams) in 300 mls of
THF. The resulting slurry was stirred three hours. The solvent was
removed under vacuum. An orange oil was extracted with pentane.
Distillation under a dynamic vacuum with heating removed
CH.sub.3(CH.sub.2=CH)Si(Cp*H)Cl. The residual oil was used without
further purification.
[0037] 2.
CH.sub.3(CH.sub.2=CH)Si(Cp*).sub.2Zr(NMe.sub.2).sub.2.
[0038] CH.sub.3(CH.sub.2=CH)Si(Cp*H).sub.2 (8.4 grams) was combined
with Zr(NMe.sub.2).sub.4 (7.2 grams) in toluene (200 mls). The
solution was stirred at 90.degree. C. overnight. The resulting
solution was concentrated and pentane was added resulting in the
isolation of an orange precipitate. (5 grams) .sup.1H NMR
(C.sub.6D.sub.6); .delta. 0.85(s), 1.92 (s), 1.97(s), 2.10(s),
2.20(s), 2.95(s), 2.96(s), 5.9-6.2 (m), 6.85-7.0 (m).
[0039] 3. CH.sub.3(CH.sub.2=CH)Si(CP*).sub.2ZrCl.sub.2.
[0040] CH.sub.3(CH.sub.2=CH)Si(Cp*).sub.2Zr(NMe.sub.2).sub.2. (5
grams) was combined with TMSC1 (>10 equivalents) in toluene (200
mls). The solution was stirred overnight. The resulting solution
was concentrated and pentane was added resulting in the isolation
of a yellow precipitate. (3.8 grams) .sup.1H NMR (C.sub.6D.sub.6);
.delta. 0.72 (s), 1.79 (s), 1.80(s), 2.05(s), 2.07(s), 5.8-6.1 (m),
6.5-6.7 (m).
[0041] 4.
CH.sub.3((C.sub.6F.sub.5).sub.2BCH.sub.2CH.sub.2)Si(Cp*).sub.2Zr-
Cl.sub.2.
[0042] CH.sub.3(CH.sub.2=CH)Si(CP*).sub.2ZrCl.sub.2 (1.4 grams) was
combined with [HB(C.sub.6F.sub.5).sub.2].sub.2 (1.0 grams) in
dichloromethane (30 mls) at -30.degree. C. The solution was warmed
to room temperature. The resulting solution was concentrated and
pentane was added resulting in the isolation of a yellow
precipitate in quantitative yields. .sup.1H NMR (C.sub.6D.sub.6);
.delta.0.8 (s), 1.4 (m), 1.79 (s), 1.87(s), 2.04(s), 2.09(s), 2.1
(m).
[0043] 5. CH.sub.3(CH.sub.2=CH)Si(IndH).sub.2.
[0044] CH.sub.3(CH.sub.2=CH)Si(IndH).sub.2 was prepared using the
procedure Jordan et al. (Organometallics 1996, 15, 4038) reported
for the synthesis of (CH.sub.3).sub.2Si(IndH).sub.2. An orange oil
was obtained and used without further purification.
[0045] 6.
rac-CH.sub.3(CH.sub.2=CH)Si(Ind).sub.2Zr(NMe.sub.2).sub.2.
[0046] CH.sub.3(CH.sub.2=CH)Si(Ind*H).sub.2 (8.4 grams) was
combined with Zr(NMe.sub.2).sub.4 (7.2 grams) in hexane (300 mls)
and attached to an oil bubbler. The solution was stirred at reflux
overnight. A dark red solution resulted. The solvent was removed
under vacuum. A minimum of pentane was added and the solution was
stored for several days at -30.degree. C. 8.5 grams of ruby red
crystals formed of one isomer. .sup.1H NMR (C.sub.6D.sub.6);
.delta.0.89 (s), 2.46 (s), 2.48(s), 6.2-6.36 (m), 6.67-7.0 (m),
7.47-7.60 (m), 7.76-7.79 (m).
[0047] 7. rac-CH.sub.3(CH.sub.2=CH)Si(Ind).sub.2ZrCl.sub.2.
[0048] CH.sub.3(CH.sub.2=CH)Si(Ind).sub.2Zr(NMe.sub.2).sub.2. (5
grams) was combined with TMSC1(>10 equivalents) in toluene (200
mls). The solution was stirred overnight. The resulting solution
was concentrated and pentane was added resulting in the isolation
of a yellow precipitate. (3.8 grams) .sup.1H NMR (C.sub.6D.sub.6);
.delta. 0.62 (s), 5.76 (d), 5.90 (d), 5.91-6.14 (m), 6.37-6.51 (m),
6.77-6.90 (m), 7.12-7.23 (m), 7.36-7.45 (m).
[0049] 8.
rac-CH.sub.3((C.sub.6F.sub.5).sub.2BCH.sub.2CH.sub.2)Si(Ind).sub-
.2ZrCl.sub.2.
[0050] CH.sub.3(CH.sub.2=CH)Si(Ind).sub.2ZrCl.sub.2 (1.85 grams)
was combined with [HB(C.sub.6F.sub.5).sub.2](1.43 grams) in
dichloromethane (30 mls) at -30.degree. C. The solution was warmed
to room temperature. The resulting solution was concentrated and
pentane was added resulting in the isolation of a yellow
precipitate (2.7 grams). .sup.1H NMR (C.sub.6D.sub.6); .delta. 0.72
(s), 1.37-1.44 (m), 2.08-2.14 (m), 5.80 (d), 5.90 (d), 6.77-6.94
(m), 7.08-7.39 (m).
[0051] Synthesis of Supported Catalysts.
[0052] 9. Catalyst A (Comparative)
[0053] Methylalumoxane (30 wt % in toluene) (37.72 grams) was
combined with 39.0 grams of toluene in a 500 ml flask. The addition
of 0.80 grams of CH.sub.3(CH.sub.2=CH)Si(CP*).sub.2ZrCl.sub.2
formed a gold solution. After several minutes 30.0 grams of Davison
948 (600.degree. C. treated) silica was poured into the solution.
The resulting mixture was stirred by hand with a spatula for ten
minutes. The supported material was dried overnight under vacuum
yielding a yellow powder.
[0054] 10. Catalyst B
[0055] Methylalumoxane (30 wt % in toluene) (37.72 grams) was
combined with 39.0 grams of toluene in a 500 ml flask. The addition
of 1.33 grams of
CH.sub.3((C.sub.6F.sub.5).sub.2BCH.sub.2CH.sub.2)Si(CP*).sub.2ZrCl.sub-
.2 formed a gold solution. After several minutes 30.0 grams of
Davison 948 (600.degree. C. treated) silica was poured into the
solution. The resulting mixture was stirred by hand with a spatula
for ten minutes. The supported material was dried overnight under
vacuum yielding a yellow powder.
[0056] 11. Catalyst C (Comparative)
[0057] Methylalumoxane (30 wt % in toluene) (37.72 grams) was
combined with 39.0 grams of toluene in a 500 ml flask. The addition
of 0.704 grams of rac--CH.sub.3(CH.sub.2=CH)Si(Ind).sub.2ZrCl.sub.2
formed a red solution. After several minutes 30.0 grams of Davison
948 (600.degree. C. treated) silica was poured into the solution.
The resulting mixture was stirred by hand with a spatula for ten
minutes. The supported material was dried overnight under vacuum
yielding a pink powder.
[0058] 12. Catalyst D
[0059] Methylalumoxane (30 wt % in toluene) (37.72 grams) was
combined with 39.0 grams of toluene in a 500 ml flask. The addition
of 1.27 grams of
rac--CH.sub.3((C.sub.6F.sub.5).sub.2BCH.sub.2CH.sub.2)Si(Ind).sub.2ZrC-
l.sub.2 formed a red solution. After several minutes 30.0 grams of
Davison 948 (600.degree. C. treated) silica was poured into the
solution. The resulting mixture was stirred by hand with a spatula
for ten minutes. The supported material was dried overnight under
vacuum yielding a pink powder.
[0060] 13. Catalyst E
[0061] Methylalumoxane (30 wt % in toluene) (37.72 grams) was
combined with 39.0 grams of toluene in a 500 ml flask. The addition
of 0.73 grams of rac--(CH.sub.3).sub.2Si(Ind).sub.2ZrCl.sub.2
formed a red solution. After several minutes 30.0 grams of Davison
948 (600.degree. C. treated) silica was poured into the solution.
The resulting mixture was stirred by hand with a spatula for ten
minutes. The supported material was dried overnight under vacuum
yielding a orange powder.
[0062] 14. Slurry-Phase Ethylene-Hexene Polymerization using
Catalyst A. (Comparative)
[0063] Polymerizations were conducted in a stainless steel, 1-liter
Zipperclave autoclave reactor. The reactor was equipped with
waterjacket for heating and cooling. Injections were performed via
a high pressure nitrogen injection. (400 mls isobutane, 15 mls of
hexene, and 15 mls triethylaluminum) Before polymerizations the
reactor was purged with nitrogen for several hours at 100.degree.
C. Upon injection of catalyst ethylene was fed continuously on
demand keeping the reactor pressure constant (130 psig ethylene)
while maintaining the reaction temperature at 85.degree. C. After
the allotted time the reaction was stopped by cooling and venting
the pressure and exposing the contents of the reactor to air. The
liquid components were evaporated and the
poly(ethylene-co-hexene-1) resin was dried under a N.sub.2 purge.
Weight average molecular weight (Mw), number average molecular
weight (Mn) and their ratio Mw/Mn were obtained by GPC gel
permeation chromotagraphy. Hexene wt % incorporation was obtained
from .sup.1H NMR data.
[0064] The above procedure was performed using 25 mgs of Catalyst
A. After 40 minutes the reaction was stopped. No reactor fouling
was observed. Run 1; 39.9 grams of polymer resin (2660 g pol. /g
cat. h); Mw=74500, Mn=36200, Mw/Mn=2.61; Hexene wt % =2.7. Run 2;
35.6 grams of polymer resin (2370 g pol. /g cat. h); Mw=85100,
Mn=35900, Mw/Mn=2.37; Hexene wt % =2.9.
[0065] 15. Slurry-Phase Ethylene-Hexene Polymerization using
Catalyst B.
[0066] The polymerization was run according to the procedure
outlined in experiment 13 using catalyst B. No reactor fouling was
observed. Run 1; 33.7 grams of polymer resin (2250 g pol. /g cat.
h); Mw=89700, Mn=36500, Mw/Mn=2.5; Hexene wt % =3.0. Run 2; 24.1
grams of polymer resin (1610 g pol. /g cat. h); Mw=89900, Mn=38100,
Mw/Mn=2.36; Hexene wt % =2.9.
[0067] 16. Slurry-Phase Ethylene-Hexene Polymerization using
Catalyst C. (Comparative)
[0068] The polymerization was run according to the procedure
outlined in experiment 13 using catalyst C. No reactor fouling was
observed. Run 1; 35.5 grams of polymer resin (2370 g pol. /g cat.
h); Mw=124000, Mn=34500, Mw/Mn=3.59; Hexene wt % =6.7. Run 2; 35.6
grams of polymer resin (2370 g pol. /g cat. h); Mw=153000,
Mn=38200, Mw/Mn=4.00; Hexene wt % =6.0.
[0069] 17. Slurry-Phase Ethylene-Hexene Polymerization using
Catalyst D.
[0070] The polymerization was run according to the procedure
outlined in experiment 13 using catalyst D. No reactor fouling was
observed. Run 1; 113 grams of polymer resin (7530 g pol. /g cat.
h); Mw=102000, Mn=35300, Mw/Mn=2.89; Hexene wt % =4.9. Run 2; 91.4
grams of polymer resin (6090 g pol. /g cat. h); Mw=92400, Mn=36200,
Mw/Mn=2.55; Hexene wt % =5.5.
[0071] 18. Slurry-Phase Ethylene-Hexene Polymerization using
Catalyst E.
[0072] The polymerization was run according to the procedure
outlined in experiment 14 using catalyst D. No reactor fouling was
observed. Run 1; 36.5 grams of polymer resin (2440 g pol. /g cat.
h); Mw=178000, Mn=42800, Mw/Mn=4.16; Hexene wt % =5.9.
* * * * *