U.S. patent application number 10/359933 was filed with the patent office on 2003-08-07 for catalyst system and its use in olefin polymerization.
Invention is credited to Kao, Sun-Chueh, Karol, Frederick J., Sher, Jaimes.
Application Number | 20030149202 10/359933 |
Document ID | / |
Family ID | 24869770 |
Filed Date | 2003-08-07 |
United States Patent
Application |
20030149202 |
Kind Code |
A1 |
Kao, Sun-Chueh ; et
al. |
August 7, 2003 |
CATALYST SYSTEM AND ITS USE IN OLEFIN POLYMERIZATION
Abstract
A polymerization catalyst system and a method for preparing the
catalyst system is disclosed. The catalyst system includes a bulky
ligand metallocene catalyst compound, preferably containing a
single cyclopentadienyl or substituted cyclopentadienyl-type ring
system, a Group 13 element containing first modifier, and a
cycloalkadiene second modifier. The present invention also provides
a process for polymerizing olefin(s) utilizing the catalyst systems
described herein.
Inventors: |
Kao, Sun-Chueh; (Belle Mead,
NJ) ; Sher, Jaimes; (Houston, TX) ; Karol,
Frederick J.; (Lakewood, NJ) |
Correspondence
Address: |
UNIVATION TECHNOLOGIES LLC
5555 SAN FELIPE, SUITE 1950
HOUSTON
TX
77056
US
|
Family ID: |
24869770 |
Appl. No.: |
10/359933 |
Filed: |
February 6, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10359933 |
Feb 6, 2003 |
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09714371 |
Nov 16, 2000 |
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6552137 |
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Current U.S.
Class: |
526/133 ;
502/108; 502/128; 502/152; 502/170; 526/134; 526/160; 526/165;
526/943 |
Current CPC
Class: |
Y10S 526/943 20130101;
C08F 210/16 20130101; C08F 210/16 20130101; C08F 210/16 20130101;
C08F 4/65908 20130101; C08F 4/6592 20130101; C08F 4/65912 20130101;
C08F 210/14 20130101; C08F 2500/03 20130101 |
Class at
Publication: |
526/133 ;
526/134; 526/160; 526/165; 526/943; 502/108; 502/128; 502/152;
502/170 |
International
Class: |
C08F 004/44 |
Claims
We claim:
1. A catalyst system for polymerizing olefin(s) comprising a) a
bulky ligand metallocene catalyst compound; b) a first modifier
comprising a Group 13 element containing compound; and c) a second
modifier comprising a cycloalkyldiene.
2. The catalyst system of claim 1 wherein the first modifier may be
represented by: (L'-H).sub.d.sup.+(A.sup.d-) wherein L' is an
neutral Lewis base; H is hydrogen; (L'-H).sup.+ is a Bronsted acid;
A.sup.d- is a non-coordinating anion having the charge d-; and d is
an integer from 1 to 3.
3. The catalyst system of claim 2 wherein (L-H).sub.d.sup.+ is
selected from the group consisting of ammoniums of methylamine,
aniline, dimethylamine, diethylamine, N-methylaniline,
diphenylamine, trimethylamine, triethylamine, N,N-dimethylaniline,
methyldiphenylamine, pyridine, p-bromo N,N-dimethylaniline,
p-nitro-N,N-dimethylaniline, phosphoniums from triethylphosphine,
triphenylphosphine, and diphenylphosphine, oxomiuns from ethers
such as dimethyl ether diethyl ether, tetrahydrofuran and dioxane,
sulfoniums from thioethers, such as diethyl thioethers and
tetrahydrothiophene and cobinations thereof.
4. The catalyst system of claim 2 wherein (L-H)d+is selected from
the group consisting of ammoniums of methylamine, aniline,
dimethylamine, diethylamine, N-methylaniline, diphenylamine,
trimethylamine, triethylamine, N,N-dimethylaniline,
methyldiphenylamine, pyridine, p-bromo N,N-dimethylaniline,
p-nitro-N,N-dimethylaniline, and combinations thereof.
5. The process of claim 2 wherein A.sup.d- may be represented by
the formula [M.sup.k+Q.sub.n].sup.d-wherein k is an integer from 1
to 3; n is an integer from 2 to 6; n-k=d; M is an element selected
from Group 13 of the Periodic Table of the Elements and Q is
independently a hydride, bridged or unbridged dialkylamido, halide,
alkoxide, aryloxide, hydrocarbyl, substituted hydrocarbyl,
halocarbyl, substituted halocarbyl, and halosubstituted-hydrocarbyl
radicals, with Q having up to 20 carbon atoms with the proviso that
in not more than 1 occurrence is Q a halide.
6. The process of claim 5 wherein each Q is a fluorinated
hydrocarbyl group having 1 to 20 carbon atoms.
7. The catalyst system of claim 1 wherein the first modifier is
selected from the group consisting of
tris(pentafluorophenyl)borane, dimethylanilinium
tetra(pentafluorophenyl)borate, dimethylanilinium
tetra(pentafluorophenyl)-aluminate, dimethylanilinium
tetrafluoroaluminate, tri(n-butyl)ammonium)
tetra(pentafluorophenyl)borat- e, tri(n-butyl)ammonium)
tetra(pentafluorophenyl)-aluminate, tri(n-butyl)ammonium)
tetrafluoroaluminate, the sodium, potassium, lithium, tropyliun and
the triphenylearbenium salts of these compounds, and combinations
thereof.
8. The catalyst system of claim 1 wherein the second modifier is
selected from the group consisting of unsubstituted and substituted
cyclopentadienes, indenes, fluorenes, fulvenes, and combinations
thereof.
9. The catalyst system of claim 1 wherein the second modifier is
selected from the group consisting of cyclopentadiene,
methylcyclopentadiene, ethylcyclopentadiene,
t-butylcyclopentadiene, hexylcyclopentadiene, octylcyclopentadiene,
1,2-dimethylcyclopentadiene, 1,3-dimethylcyclopentadiene,
1,2,4-trimethylcyclopentadiene, 1,2,3,4-tetramethylcyclopentadiene,
pentamethylcyclopentadiene, indene, 4-methyl-1-indene,
4,7-dimethylindene, 4,5,6,7-tetrahydroindene, fluorene,
methylfluorene, cycloheptatriene, methylcycloheptatriene,
cyclooctatraene, methylcyclooctatraene, fulvene and
dimethylfulvene. bis-indenylethane,
bis(4,5,6,7-tetrahydro-1-indenyl)ethane,
1,3-propanedinyl-bis(4,5,6,7-tetrahydro)indene,
propylene-bis(1-indene), isopropyl(1-indenyl) cyclopentadiene,
diphenylmethylene(9-fluorenyl), cyclopentadiene,
isopropylcyclopentadienyl-1-fluorene and combinations thereof.
10. The catalyst system of claim 1, wherein said second modifier is
a 1,3-diene.
11. The catalyst system of claim 1, wherein said second modifier is
indene.
12. The catalyst system of claim 1 wherein the molar ratio of the
first modifier to the metal contained in the bulky ligand
metallocene catalyst compound is about 0.01 to 100
13. The catalyst system of claim 1 wherein the molar ratio of the
first modifier to the metal contained in the bulky ligand
metallocene catalyst compound is about 0.01 to 10.
14. The catalyst system of claim 1 wherein the molar ratio of the
second modifier to the metal contained in the bulky ligand
metallocene catalyst compound is about 0.01 to 100
15. The catalyst system of claim 1 wherein the molar ratio of the
second modifier to the metal contained in the bulky ligand
metallocene catalyst compound is about 0.01 to 10.
16. The catalyst system of claim 1 wherein the bulky ligand
metallocene catalyst compound is represented by LMX.sub.n wherein:
M is a metal atom from Groups 3 to 15 or the Lanthanide series of
the Periodic Table of Elements; L is a substituted or
unsubstituted, .pi.-bonded bulky ligand coordinated to M, each X is
independently selected from the group consisting of hydrogen, an
aryl, alkyl, alkenyl, alkylaryl, or arylalkyl radical having 1 to
20 carbon atoms, a hydrocarboboxy radical having 1 to 20 carbon
atoms, a halide, and a nitrogen containing radical having 1 to 20
carbon atoms; and wherein n is 2, 3 or 4 depending on the valence
of M.
17. The catalyst system of claim 1, wherein the bulky ligand
metallocene catalyst compound is represented by either: 5wherein: M
is a metal atom from Groups 3 to 15 or the Lanthanide series of the
Periodic Table of Elements; L is a substituted or unsubstituted,
.pi.-bonded bulky ligand coordinated to M Each Q can be the same or
different and is independently selected from the group consisting
of --O--, --NR--, --CR.sub.2- and --S--; Y is C or S; Z is selected
from the group consisting of --OR, --NR.sub.2, --CR.sub.3, --SR,
--SiR.sub.3, --PR.sub.2, --H, and substituted or unsubstituted aryl
group with the proviso that when Q is --NR-- then Z is selected
from the group consisting of --OR, --NR.sub.2, --SR, --SiR.sub.3,
--PR.sub.2 and --H; n is 1 or 2; A is a univalent anionic group
when n is 2 or A is a divalent anionic group when n is 1; when n is
2, A can be the group formed by QQYZ depicted in formula I above;
and R can be the same or different and is independently a group
containing carbon, silicon, nitrogen, oxygen, and/or phosphorus
wherein one or more R groups may be attached to the L substituent;
or 6wherein: M is a metal atom from Groups 3 to 15 or the
Lanthanide series of the Periodic Table of Elements; L is a
substituted or unsubstituted, .pi.-bonded ligand coordinated to M;
Q can be the same or different and is independently selected from
the group consisting of --O--, --NR--, --CR.sub.2-- and --S--Y is
either C or S; Z is selected from the group consisting of --OR,
--NR.sub.2, --CR.sub.3, --SR, --SiR.sub.3, --PR.sub.2, --H, and
substituted or unsubstituted aryl group with the proviso that when
Q is --NR-- then Z is selected from the group consisting of --OR,
--NR.sub.2, --SR, --SiR.sub.3, --PR.sub.2 and --H; n is 1 or 2; A
is a univalent anionic group when n is 2 or A is a divalent anionic
group when n is 1; when n is 2, A can be the group formed by QQYZ
depicted in formula II above; R can be the same or different and is
independently a group containing carbon, silicon, nitrogen, oxygen,
and/or phosphorus wherein one or more R groups may be attached to
the L substituent; T is a bridging group selected from the group
consisting of an alkylene or arylene group containing from 1 to 10
carbon atoms optionally substituted with carbon or heteroatoms,
germaniun, silicone and alkyl phosphine; and m is 1 to 7.
18. The catalyst system of claim 1 wherein the catalyst system
further comprises an activator compound selected from the group
consisting of methylalumoxane, modified methylalumoxane and
combinations thereof.
19. The catalyst system of claim 1, wherein the bulky ligand
metallocene catalyst is selected from the group consisting of a
mono-cyclopentadienyl zirconium triscarboxylate, a
mono-cyclopentadienyl zirconium trispivalate,
1,3-dimethylcyclopentadienylzirconium and wherein the catalyst
system has an activity at least 400% greater than the activity of a
different catalyst system comprising the same bulky ligand
metallocene catalyst with no modifier.
Description
RELATED APPLICATION DATA
[0001] The present application is a divisional of U.S. patent
application Ser. No. 09/714,371, filed Nov. 16, 2000, now issued as
U.S. Pat. No. ______.
FIELD OF THE INVENTION
[0002] The present invention relates generally to the field of
bulky ligand metallocene catalysts and their use for olefin(s)
polymerization. In particular, the invention is directed to a
catalyst system with enhanced activity, which includes a bulky
ligand metallocene catalyst compound and a method for preparing
such a system. More specifically, the present invention is directed
to a catalyst system comprising a bulky ligand metallocene catalyst
compound, an activator compound, a Group 13 element containing
first modifier, and a cycloalkadiene second modifier, to a method
of preparing such a catalyst system, and for its use in the
polymerization of olefin(s).
BACKGROUND OF THE INVENTION
[0003] Numerous catalysts and catalyst systems have been developed
that provide polyolefins with certain advantageous properties. One
class of these catalysts are now commonly referred to as
metallocenes. Metallocenes are broadly defined as organometallic
coordination complexes containing one or more moieties in
association with a metal atom from Groups 3 to 17 or the Lanthanide
series of the Periodic Table of Elements. These catalysts are
highly useful in the preparation of polyolefins, allowing one to
closely tailor the final properties of a polymer.
[0004] Although metallocene catalysts are used extensively to
obtain polyolefins with molecular weight, polydispersity, melt
index, and other properties well suited for a desired application,
the use of these catalysts is expensive. It is therefore an object
of this invention to increase the activity of metallocene catalyst
systems and thereby reduce the cost associated with utilizing such
a system.
[0005] Organoborate and boron compounds are known as activators for
olefin polymerization systems. The use of these compounds as
activators, instead of alumoxane compounds, to form active olefin
polymerization catalysts is documented in the literature. Marks
(Marks et al. 1991) reported such a transformation for olefin
polymerization using Group 4 metallocene catalysts containing alkyl
leaving groups activated with tris(pentafluorophenyl)borane.
Similarly, Chien et al. (1991) activated a dimethyl zirconium
catalyst with tetra(pentafluorophenyl)borate. However, when Chien
used methylalumoxane (MAO) as well as the borate for the activation
of the dimethyl zirconium catalyst for the polymerization of
propylene, only a small amount of polymer was produced.
[0006] U.S. Pat. No. 5,747,406 discloses an increased catalytic
activity when using indene or other cycloalkadienes with a
half-sandwich transition metal catalyst and MAO as the activating
activator. This catalyst composition demonstrates enhanced activity
in the polymerization of olefins. For the polymerization of
ethylene/1-hexene using indenyl zirconium tris(diethyl-carbamate),
modified MAO and indene, the addition of indene increased the
activity of the system 3.5 times.
[0007] In spite of the advances in the prior art, there exists a
need to provide for a highly active metallocene catalyst systems,
for a method for its preparation and use in the polymerization of
olefin(s).
SUMMARY OF THE INVENTION
[0008] The present invention provides a catalyst system and a
method for preparing a catalyst system which includes a bulky
ligand metallocene catalyst compound, an activator compound, a
Group 13 element containing first modifier, and a cycloalkadiene
second modifier. The first and second modifiers, when utilized
together, act to enhance the activity of the catalyst system. The
present invention also provides a process for polymerizing
olefin(s) utilizing the catalyst systems described herein.
DETAILED DESCRIPTION OF THE INVENTION
[0009] The present invention provides a metallocene catalyst system
having enhanced activity, a method for preparing this catalyst
system and a method for polymerizing olefin(s) utilizing same. More
specifically, the present invention provides for a catalyst system
which includes a bulky ligand metallocene catalyst compound,
preferably a half sandwich bulky ligand metallocene catalyst
compound, an activator compound, a Group 13 element containing
first modifier, and a cycloalkyldiene second modifier.
[0010] Bulky Ligand Metallocene Compounds
[0011] The catalyst system of the invention includes a bulky ligand
metallocene catalyst. Bulky ligand metallocene compounds generally
include both half and full sandwich compounds having one or more
bulky ligands bonded to at least one metal atom. Typical bulky
ligand metallocene compounds are generally described as containing
one or more bulky ligand(s) and one or more leaving group(s) bonded
to at least one metal atom. The bulky ligand metallocene compounds
preferred include one unsubstituted or substituted,
cyclopentadienyl ligand or cyclopentadienyl-type ligand. These
types of bulky ligand metallocene compounds are also referred to as
half-sandwich compounds or mono-cyclopentadienyl compounds
(mono-Cps), and the terms are used interchangeably herein.
[0012] The unsubstituted or substituted, cyclopentadienyl ligand or
cyclopentadienyl-type bulky ligand, is generally represented by one
or more open, acyclic, or fused ring or ring system typically
composed of atoms selected from Groups 13 to 16 atoms of the
Periodic Table of Elements. Preferably the atoms are selected from
the group consisting of carbon, nitrogen, oxygen, silicon, sulfur,
phosphorous, germanium, boron and aluminum or a combination
thereof. The unsubstituted or substituted, cyclopentadienyl ligands
or cyclopentadienyl-type ligands include heteroatom substituted
and/or heteroatom containing cyclopentadienyl-type ligands.
[0013] Non-limiting examples of these bulky ligands include
cyclopentadienyl ligands, cyclopentaphenanthreneyl ligands, indenyl
ligands, benzindenyl ligands, fluorenyl ligands, octahydrofluorenyl
ligands, cyclooctatetraendiyl ligands, cyclopentacyclododecene
ligands, azenyl ligands, azulene ligands, pentalene ligands,
phosphoyl ligands, phosphinimine (WO 99/40125), pyrrolyl ligands,
pyrozolyl ligands, carbazolyl ligands, borabenzene ligands and the
like, including hydrogenated versions thereof, for example
tetrahydroindenyl ligands.
[0014] Bulky ligands which comprise one or more heteroatoms include
those ligands containing nitrogen, silicon, boron, germanium,
sulfur and phosphorous, in combination with carbon atoms to form an
open, acyclic, or preferably a fused, ring or ring system, such as,
for example, a heterocyclopentadienyl ancillary ligand. Other bulky
ligands include but are not limited to bulky amides, phosphides,
alkoxides, aryloxides, imides, carbolides, borollides, porphyrins,
phthalocyanines, corrins and other polyazomacrocycles.
[0015] The cyclopentadienyl ligand or cyclopentadienyl-type bulky
ligand may be unsubstituted or substituted with a combination of
substituent groups R. Non-limiting examples of substituent groups R
include one or more from the group selected from hydrogen, or
linear, branched alkyl radicals, or alkenyl radicals, alkynyl
radicals, cycloalkyl radicals or aryl radicals, acyl radicals,
aroyl radicals, alkoxy radicals, aryloxy radicals, alkylthio
radicals, dialkylamino radicals, alkoxycarbonyl radicals,
aryloxycarbonyl radicals, carbomoyl radicals, alkyl- or
dialkyl-carbamoyl radicals, acyloxy radicals, acylamino radicals,
aroylamino radicals, straight, branched or cyclic, alkylene
radicals, or combination thereof. In a preferred embodiment,
substituent groups R have up to 50 non-hydrogen atoms, preferably
from 1 to 30 carbon, that can also be substituted with halogens or
heteroatoms or the like. Non-limiting examples of alkyl
substituents R include methyl, ethyl, propyl, butyl, pentyl, hexyl,
cyclopentyl, cyclohexyl, benzyl or phenyl groups and the like,
including all their isomers, for example tertiary butyl, isopropyl,
and the like. Other hydrocarbyl radicals include fluoromethyl,
fluroethyl, difluroethyl, iodopropyl, bromohexyl, chlorobenzyl and
hydrocarbyl substituted organometalloid radicals including
trimethylsilyl, trimethylgermyl, methyldiethylsilyl and the like;
and halocarbyl-substituted organometalloid radicals including
tris(trifluoromethyl)-silyl, methyl-bis(difluoromethyl)silyl,
bromomethyldimethylgermyl and the like; and disubstitiuted boron
radicals including dimethylboron for example; and disubstituted
pnictogen radicals including dimethylamine, dimethylphosphine,
diphenylamine, methylphenylphosphine, chalcogen radicals including
methoxy, ethoxy, propoxy, phenoxy, methylsulfide and ethylsulfide.
Non-hydrogen substituents R include the atoms carbon, silicon,
boron, aluminum, nitrogen, phosphorous, oxygen, tin, sulfur,
germanium and the like, including olefins such as but not limited
to olefinically unsaturated substituents including vinyl-terminated
ligands, for example but-3-enyl, prop-2-enyl, hex-5-enyl and the
like. Also, at least two R groups, preferably two adjacent R
groups, are joined to form a ring structure having from 3 to 30
atoms selected from carbon, nitrogen, oxygen, phosphorous, silicon,
germanium, aluminum, boron or a combination thereof. Also, a
substituent group R group such as 1-butanyl may form a carbon sigma
bond to the metal M.
[0016] The metal atom is preferably selected from Groups 3 through
15 and the lanthanide or actinide series of the Periodic Table of
Elements. Preferably the metal is a transition metal from Groups 4
through 12, more preferably Groups 4, 5 and 6, even more preferably
the transition metal is from Group 4 and most preferably titanium,
zirconium or hafnium.
[0017] In one embodiment, the half-sandwich or mono-Cp bulky ligand
catalyst compounds utilized in the catalyst system of the invention
is represented by Formula I as set forth below:
LMX.sub.n Formula I
[0018] wherein:
[0019] M is a metal atom from Groups 3 to 15 or the Lanthanide
series of the Periodic Table of Elements, preferably Groups 4, 5
and 6, even more preferably Group 4 and most preferably Ti, Zr or
Hf;
[0020] L is a substituted or unsubstituted, 7r-bonded bulky ligand
coordinated to M, preferably a substituted or unsubstituted
cyclopentadienyl or cyclopentadienyl-type ligand;
[0021] each X is independently hydrogen, an aryl, alkyl, alkenyl,
alkylaryl, or arylalkyl radical having 1 to 20 carbon atoms, a
hydrocarboxy radical having 1 to 20 carbon atoms, a halide, a
nitrogen containing radical having 1 to 20 carbon atoms; and
wherein
[0022] the value of n depends upon the valence state of M and is
preferably 2, 3 or 4.
[0023] In another embodiment, the half-sandwich or mono-Cp bulky
ligand catalyst compounds utilized in the catalyst system of the
invention is represented by Formula II or Formula III as set forth
below: 1
[0024] wherein:
[0025] M is a metal atom from Groups 3 to 15 or the Lanthanide
series of the Periodic Table of Elements, preferably Groups 4, 5
and 6, even more preferably Group 4 and most preferably Ti, Zr or
Hf;
[0026] L is a substituted or unsubstituted, .pi.-bonded bulky
ligand coordinated to M, preferably a substituted or unsubstituted
cyclopentadienyl or cyclopentadienyl-type ligand;
[0027] Q can be the same or different and is independently selected
from the group consisting of --O--, --NR--, --CR.sub.2 and
--S--;
[0028] Y is either C or S;
[0029] Z is selected from the group consisting of --OR, --NR.sub.2,
--CR.sub.3, --SR, --SiR.sub.3, --PR.sub.2, --H, and substituted or
unsubstituted aryl group with the proviso that when Q is --NR--
then Z is selected from the group consisting of --OR, --NR.sub.2,
--SR, --SiR.sub.3, --PR.sub.2 and --H;
[0030] n is 1 or 2;
[0031] A is a univalent anionic group when n is 2 or A is a
divalent anionic group when n is 1; when n is 2, A can be the group
formed by QQYZ depicted in formula I above; and
[0032] As used above, each R can be the same or different and is
independently a group containing carbon, silicon, nitrogen, oxygen,
and/or phosphorus where one or more R groups may be attached to the
L substituent, preferably R is a hydrocarbon group containing from
1 to 20 carbon atoms, most preferably an alkyl, cycloalkyl or an
aryl group; and 2
[0033] wherein:
[0034] M is a metal atom from Groups 3 to 15 or the Lanthanide
series of the Periodic Table of Elements, preferably Groups 4, 5
and 6, even more preferably Group 4 and most preferably Ti, Zr or
Hf;
[0035] L is a substituted or unsubstituted, .pi.-bonded bulky
ligand coordinated to M, preferably a substituted or unsubstituted
cyclopentadienyl or cyclopentadienyl-type ligand;
[0036] Q can be the same or different and is independently selected
from the group consisting of --O--, --NR--, --CR.sub.2-- and
--S--
[0037] Y is either C or S;
[0038] Z is selected from the group consisting of --OR, --NR.sub.2,
--CR.sub.3, --SR, --SiR.sub.3, --PR.sub.2, --H, and substituted or
unsubstituted aryl group with the proviso that when Q is --NR--
then Z is selected from the group consisting of --OR, --NR.sub.2,
--SR, --SiR.sub.3, --PR.sub.2 and --H;
[0039] n is 1 or 2;
[0040] A is a univalent anionic group when n is 2 or A is a
divalent anionic group when n is 1; when n is 2, A can be the group
formed by QQYZ depicted in formula II above;
[0041] R can be the same or different and is independently a group
containing carbon, silicon, nitrogen, oxygen, and/or phosphorus
where one or more R groups may be attached to the L substituent,
preferably R is a hydrocarbon group containing from 1 to 20 carbon
atoms, most preferably an alkyl, cycloalkyl or an aryl group;
[0042] T is a bridging group selected from the group consisting of
an alkylene or arylene group containing from 1 to 10 carbon atoms
optionally substituted with carbon or heteroatoms, germaniun,
silicone and alkyl phosphine; and
[0043] m is 1 to 7, preferably 2 to 6, most preferably 2 or 3.
[0044] In Formula II and III above, the substituent formed by Q, Q,
Y and Z is preferably a unicharged polydentate ligand exerting
electronic effects due to its high polarizibility, similar to the
cyclopentadienyl group (L) described above. In preferred
embodiments of this invention, the disubstituted carbamates, shown
in Formula IV, 3
[0045] and the carboxylates, shown in Formula V, 4
[0046] are employed.
[0047] Illustrative examples of these mono-Cp bulky ligand
metallocene catalyst compounds are which may be utilized in the
catalyst system of the invention include: indenyl zirconium
tris(pivalate), indenyl zirconium tris(p-toluate), indenyl
zirconium tris(benzoate), (1-methylindenyl) zirconium
tris(pivalate), (2-meth-ylindenyl) zirconium
tris(diethylcarbamate), (methylcyclopentadienyl) zirconium
tris(pivalate), (cyclopentadienyl) zirconium tris(pivalate),
(pentamethylcyclopentadienyl) zirconium tris(benzoate),
n-butylcyclopentadienylzirconium trispivalate,
(n-butylcyclopenta-dienyl)- tris-(benzoate),
(tetrahydroindenyl)zirconium tris(pivalate),
(tetrahydroindenyl)-zirconium tris(benzoate),
(tetrahydroindenyl)zirconiu- m tris(pentenate),
(1,3-dimethylcyclopentadienyl)zirconium tris(pivalate),
(1,3-methylethyl-cyclopentadienyl)zirconium tris(pivalate),
tetramethylcyclopentadienyl)zirconium tris(pivalate),
(pentamethylcyclopentadienyl)zirconium tris(pivalate),
(cyclopenty-lcyclopentadienyl)zirconium tris(benzoate),
(benzylcyclopentadienyl)zirconium tris(benzoate),
(n-butylcyclopentadieny- l)hafnium tris(pivalate),
(n-butylcyclopentadienyl)titanium tris(pivalate).
pentamethylcyclopentadienyltitanium isopropoxide,
pentamethylcyclopentadienyltribenzyl titanium,
dimethylsilyltetramethylcy- clopentadienyl-tert-butylamido titanium
dichloride, pentamethylcyclopentadienyl titanium trimethyl,
dimethylsilyltetramethyl-- cyclopentadienyl-tert-butylamido
zirconium dimethyl,
dimethylsilyltetramethyl-cyclopentadienyl-dodecylamido hafnium
dihydride and
dimethylsilyltetramethyl-cyclopentadienyl-dodecylamido hafnium
dimethyl. Particularly preferred mono-Cp compounds utilized are
1,3-dimethylcyclopentadienylzirconium trispivalate and
indenylzirconium trispivalate.
[0048] The above mono-Cp bulky ligand metallocene catalyst
compounds may be made using any conventional process as is well
known. In one method of manufacturing this catalyst, a source of
cyclopentadienyl-type ligand is reacted with a metal compound of
the formula M(CR.sub.2).sub.4 or M(NR.sub.2).sub.4 in which M and R
are defined above. The resulting product is then dissolved in an
inert solvent, such as toluene, and the heterocummulene such as
CO.sub.2, is contacted with the dissolved product to insert into
one or more M-CR.sub.2 or M-NR.sub.2 bonds to form, in this
instance, a carboxylate or a carbamate. In another method of
manufacturing this catalyst is described in WO 00/10709, published
Jan. 13, 2000, and incorporated herein by reference.
[0049] Activator Compounds
[0050] The above described polymerization catalyst compounds are
typically activated in various ways to yield compounds having a
vacant coordination site that will coordinate, insert, and
polymerize olefin(s). The catalyst system of the invention may
include a single activator compound or a combination of activator
compounds. For the purposes of this patent specification and
appended claims, the term "activator" is defined to be any compound
or component or method which can convert a neutral bulky ligand
metallocene catalyst compound to a catalytically active bulky
ligand metallocene catalyst cation.
[0051] In one embodiment, the catalyst system of the invention
includes an alumoxane as an activator. Alumoxane activators are
generally oligomeric compounds containing --Al(R)--O-- subunits,
where R is an alkyl group. Examples of alumoxanes include
methylalumoxane (MAO), modified methylalumoxane (MMAO),
ethylalumoxane and isobutylalumoxane. Alumoxanes may be produced by
the hydrolysis of the respective trialkylaluminum compound. MMAO
may be produced by the hydrolysis of trimethylaluminum and a higher
trialkylaluminum such as triisobutylaluminum and are generally more
soluble in aliphatic solvents and more stable during storage. There
are a variety of methods for preparing alumoxane and modified
alumoxanes, non-limiting examples of which are described in U.S.
Pat. No. 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, 5,308,815,
5,329,032, 5,248,801, 5,235,081, 5,157,137, 5,103,031, 5,391,793,
5,391,529, 5,693,838, 5,731,253, 5,731,451, 5,744,656, 5,847,177,
5,854,166, 5,856,256 and 5,939,346 and European publications EP-A-0
561 476, EP-B1-0 279 586, EP-A-0 594-218 and EP-B1-0 586 665, and
PCT publication WO 94/10180, all of which are herein fully
incorporated by reference.
[0052] In another embodiment the catalyst system of the invention
includes modified methyl alumoxane in heptane (MMAO3A) commercially
available from Akzo Chemicals, Inc., Holland, under the trade name
Modified Methylalumoxane type 3A.
[0053] In another embodiment, organoaluminum compounds are utilized
as activators. Non limiting examples of suitable organoaluminum
activator compounds include trimethylaluminum, triethylaluminum,
triisobutylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum and
the like.
[0054] In another embodiment, other suitable activators which may
be utilized are disclosed in WO 98/09996, incorporated herein by
reference, which describes activating bulky ligand metallocene-type
catalyst compounds with perchlorates, periodates and iodates
including their hydrates. WO 98/30602 and WO 98/30603, incorporated
by reference, describe the use of lithium
(2,2'-bisphenyl-ditrimethylsilicate).4THF as an activator for a
bulky ligand metallocene catalyst compound.
[0055] In another embodiments, the catalyst system of the invention
may include activators such as those disclosed in WO 99/18135,
which describes the use of organo-boron-aluminum acitivators,
EP-B1-0 781 299 which describes using a silylium salt in
combination with a non-coordinating compatible anion, both
incorporated herein by reference. Additional methods of activation
such as using radiation (see EP-B 1-0 615 981 herein incorporated
by reference), electrochemical oxidation, and the like are also
contemplated as activating methods for the purposes of rendering
the neutral bulky ligand metallocene catalyst compound or precursor
to a bulky ligand metallocene cation capable of polymerizing
olefins. Other activators or methods for activating a bulky ligand
metallocene-type catalyst compound are described in for example,
U.S. Pat. Nos. 5,849,852, 5,859,653 and 5,869,723 and WO 98/32775,
WO 99/42467
(dioctadecylmethylammonium-bis(tris(pentafluorophenyl)borane)
benzimidazolide), which are herein incorporated by reference. Still
other activators include those described in PCT publication WO
98/07515 such as tris (2,2',2"-nonafluorobiphenyl) fluoroaluminate,
also incorporated herein by reference. Combinations of activators
are also contemplated by the invention, please see for example,
EP-B1 0 573 120, PCT publications WO 94/07928 and WO 95/14044 and
U.S. Pat. Nos. 5,153,157 and 5,453,410 all of which are fully
incorporated herein by reference.
[0056] Modifiers for the Catalyst System
[0057] The catalyst system of the present invention also includes a
Group 13 element containing first modifier and a cycloalkadienyl
second modifier which, when utilized together, act to enhance the
activity of the catalyst system.
[0058] Group 13 Element Containing First Modifier
[0059] In one embodiment, the first modifier is utilized in the
catalyst system of the present invention includes a cation and an
anion component, and is represented by Formula VI below:
(L'-H).sub.d.sup.+(A.sup.d-) Formula VI
[0060] wherein L' is an neutral Lewis base;
[0061] H is hydrogen;
[0062] (L'-H).sup.+is a Bronsted acid
[0063] A.sup.d- is a non-coordinating anion having the charge
d-
[0064] d is an integer from 1 to 3.
[0065] The cation component, (L-H).sub.d.sup.+ may include Bronsted
acids such as protons or protonated Lewis bases or reducible Lewis
acids capable of protonating or abstracting a moiety, such as an
akyl or aryl, from the bulky ligand metallocene catalyst compound,
resulting in a cationic transition metal species.
[0066] In one embodiment the cation component (L-H).sub.d.sup.+
includes ammoniums, oxoniums, phosphoniums, silyliums and mixtures
thereof, preferably ammoniums of methylamine, aniline,
dimethylamine, diethylamine, N-methylaniline, diphenylamine,
trimethylamine, triethylamine, N,N-dimethylaniline,
methyldiphenylamine, pyridine, p-bromo N,N-dimethylaniline,
p-nitro-N,N-dimethylaniline, phosphoniums from triethylphosphine,
triphenylphosphine, and diphenylphosphine, oxomiuns from ethers
such as dimethyl ether diethyl ether, tetrahydrofuran and dioxane,
sulfoniums from thioethers, such as diethyl thioethers and
tetrahydrothiophene and mixtures thereof. In a preferred
embodiment, the cation component (L-H).sub.d.sup.+ of the first
modifier is dimethylanaline.
[0067] In another embodiment cation component (L-H).sub.d.sup.+ may
also be an abstracting moiety such as silver, carboniums,
tropylium, carbeniums, ferroceniums and mixtures, preferably
carboniums and ferroceniums. In a preferred embodiment, the cation
component (L-H).sub.d.sup.+ of the first modifier is triphenyl
carbonium.
[0068] In another embodiment, the anion component A.sub.d.sup.- of
the first modifier includes those anions having the formula
[M.sup.k+Q.sub.n].sup.d- wherein k is an integer from 1 to 3; n is
an integer from 2 to 6; n-k=d; M is an element selected from Group
13 of the Periodic Table of the Elements and Q is independently a
hydride, bridged or unbridged dialkylamido, halide, alkoxide,
aryloxide, hydrocarbyl, substituted hydrocarbyl, halocarbyl,
substituted halocarbyl, and halosubstituted-hydrocarbyl radicals,
with Q having up to 20 carbon atoms with the proviso that in not
more than 1 occurrence is Q a halide. In a preferred embodiment,
each Q is a fluorinated hydrocarbyl group having 1 to 20 carbon
atoms, more preferably each Q is a fluorinated aryl group, and most
preferably each Q is a pentafluoryl aryl group.
[0069] In another embodiment, the anion component A.sup.d- of the
first modifier may also include diboron compounds as disclosed in
U.S. Pat. No. 5,447,895, which is fully incorporated herein by
reference.
[0070] In another embodiment the first modifier is a
tri-substituted boron, tellurium, aluminum, gallium, or indium
compound or mixtures thereof. The three substituent groups are each
independently selected from alkyls, alkenyls, halogen, substituted
alkyls, aryls arylhalides, alkoxy and halides. Preferably, the
three groups are independently selected from halogen, mono or
multicyclic (including halosubstituted) aryls, alkyls, and alkenyl
compounds and mixtures thereof, preferred are alkenyl groups having
1 to 20 carbon atoms, alkyl groups having 1 to 20 carbon atoms,
alkoxy groups having 1 to 20 carbon atoms and aryl groups having 3
to 20 carbon atoms (including substituted aryls). In another
embodiment, the three groups are alkyls having 1 to 4 carbon
groups, phenyl, napthyl or mixtures thereof. In another embodiment
each of the three substituent groups is a fluorinated hydrocarbyl
group having 1 to 20 carbon atoms, preferably a fluorinated aryl
group, and more preferably a pentafluoryl aryl group. In another
embodiment the first modifier is trisperfluorophenyl boron or
trisperfluoronapthyl boron.
[0071] In another embodiment the first modifier or activity
promoter is an organometallic compound such as the Group 13
organometallic compounds of U.S. Pat. Nos. 5,198,401, 5,278,119,
5,407,884, 5,599,761 5,153,157, 5,241,025, and WO-A-93/14132,
WO-A-94/07927, and WO-A-95/07941, all documents are incorporated
herein by reference.
[0072] In another embodiment, the first modifier is selected from
tris(pentafluorophenyl)borane (BF-15), dimethylanilinium
tetra(pentafluorophenyl)borate (BF-20), dimethylanilinium
tetra(pentafluorophenyl)aluminate, dimethylanilinium
tetrafluoroaluminate, tri(n-butyl)ammonium)
tetra(pentafluorophenyl)borat- e, tri(n-butyl)ammonium)
tetra(pentafluorophenyl)-aluminate, tri(n-butyl)ammonium)
tetrafluoroaluminate, the sodium, potassium, lithium, tropyliun and
the triphenylcarbenium salts of these compounds, or from
combinations thereof. In preferred embodiment, the first modifier
is N,N-dimethylanilinium tetra(perfluorophenyl)borate or
triphenylcarbenium tetra(perfluorophenyl)borate.
[0073] Cycloalkadienyl Second Modifier
[0074] The use of a second modifier in combination with first
modifiers in the catalyst system of the invention significantly
enhances the catalyst system's activity.
[0075] In one embodiment, the second modifier or activity promotor
utilized in the catalyst system a cycloalkadiene compound. A
cycloalkadiene is an organocyclic compound having two or more
conjugated double bonds, examples of which include cyclic
hydrocarbon compounds having 2 to 4 conjugated double bonds and 4
to 24, preferably 4 to 12, carbons atoms. The cycloalkadiene may
optionally be substituted with a group such as alkyl or aryl of 1
to 12 carbon atoms.
[0076] Examples of activity enhancing cycloalkadienes include
unsubstituted and substituted cyclopentadienes, indenes, fluorenes,
and fulvenes, such as cyclopentadiene, methylcyclopentadiene,
ethylcyclopentadiene, t-butylcyclopentadiene, hexylcyclopentadiene,
octylcyclopentadiene, 1,2-dimethylcyclopentadiene,
1,3-dimethylcyclopentadiene, 1,2,4-trimethylcyclopentadiene,
1,2,3,4-tetramethylcyclopentadiene, pentamethylcyclopentadiene,
indene, 4-methyl-1-indene, 4,7-dimethylindene,
4,5,6,7-tetrahydroindene, fluorene, methylfluorene,
cycloheptatriene, methylcycloheptatriene, cyclooctatraene,
methylcyclooctatraene, fulvene and dimethylfulvene. These compounds
may be bonded through an alkylene group of 2-8, preferably 2-3,
carbon atoms, such as for example bis-indenylethane,
bis(4,5,6,7-tetrahydro-1-indenyl)ethane,
1,3-propanedinyl-bis(4,5,6,7-tet- rahydro)indene,
propylene-bis(1-indene), isopropyl(1-indenyl) cyclopentadiene,
diphenylmethylene(9-fluorenyl), cyclopentadiene and
isopropylcyclopentadienyl-1-fluorene. Preferred cycloalkydienes are
the 1,3-type dienes such cyclopentadiene and indene.
[0077] In the catalyst system of this invention, the addition of
the first and second modifiers, described above, have been found to
have a synergistic effect on the catalytic activity of a bulky
ligand metallocene mono-Cp/MAO catalyst component. When the first
modifier, for example BF-20, is used alone, no enhancement of the
polymerization activity occurs, and when the second modifier, for
example indene, is used alone as a modifier the enhancement is not
as significant as when both are utilized together. It is therefore
an aspect of the present invention that the activity of the
catalyst system for the polymerization of olefins is enhanced
relative to the activity of the same catalyst system without the
addition of the Group 13 element containing and the cycloalkadiene
modifiers. In one embodiment of the invention, the activity of the
catalyst system is increased at least 200%, more preferably at
least 400%, more preferably 600%, more preferably at least 700%,
more preferably at least 800%, more preferably at least 900%, or
more preferably at least 1000% relative to the activity of the same
catalyst system to which no modifier has been added.
[0078] In one embodiment, each of the modifiers are added in an
amount necessary to effect an increase in the catalyst systems
activity. In another embodiment, the molar ratio of the Group 13
element containing first modifier to the metal contained in the
bulky ligand metallocene catalyst compound is about 0.01 to 100,
preferably about 0.01 to 10, more preferably 0.05 to 5 and even
more preferably 0.1 to 2.0. In another embodiment, the molar ratio
of the cycloalkadiene second modifier to the metal contained in the
bulky ligand metallocene catalyst compound is about 0.01 to 100,
preferably about 0.01 to 10, more preferably about 0.05 to 5, and
even more preferably 0.1 to 2.0.
[0079] Polymerization Process
[0080] The catalyst system of the invention described above is
suitable for use in any polymerization process over a wide range of
temperatures and pressures. The temperatures may be in the range of
from -60.degree. C. to about 280.degree. C., preferably from
50.degree. C. to about 200.degree. C., and the pressures employed
may be in the range from 1 atmosphere to about 500 atmospheres or
higher.
[0081] Polymerization processes include solution, gas phase, slurry
phase and a high pressure process or a combination thereof.
Particularly preferred is a gas phase or slurry phase
polymerization of one or more olefins at least one of which is
ethylene or propylene.
[0082] In one embodiment, the process of this invention is directed
toward a solution, high pressure, slurry or gas phase
polymerization process of one or more olefin monomers having from 2
to 30 carbon atoms, preferably 2 to 12 carbon atoms, and more
preferably 2 to 8 carbon atoms. Polyolefins that can be produced
using these catalyst systems include, but are not limited to,
homopolymers, copolymers and terpolymers of ethylene and higher
alpha-olefins containing 3 to about 12 carbon atoms, such as
propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, and
1-octene, with densities ranging from about 0.86 to about 0.97;
polypropylene; ethylene/propylene rubbers (EPR's);
ethylene/propylene/diene terpolymers (EPDM's); and the like.
[0083] Other monomers useful in the process of the invention
include ethylenically unsaturated monomers, diolefins having 4 to
18 carbon atoms, conjugated or nonconjugated dienes, polyenes,
vinyl monomers and cyclic olefins. Non-limiting monomers useful in
the invention may include norbornene, norbornadiene, isobutylene,
isoprene, vinylbenzocyclobutane, styrenes, alkyl substituted
styrene, ethylidene norbornene, dicyclopentadiene and
cyclopentene.
[0084] In the most preferred embodiment of the process of the
invention, a copolymer of ethylene is produced, where with
ethylene, a comonomer having at least one alpha-olefin having from
4 to 15 carbon atoms, preferably from 4 to 12 carbon atoms, and
most preferably from 4 to 8 carbon atoms, is polymerized in a gas
phase process.
[0085] Typically in a gas phase polymerization process a continuous
cycle is employed wherein one part of the cycle of a reactor
system, a cycling gas stream, otherwise known as a recycle stream
or fluidizing medium, is heated in the reactor by the heat of
polymerization. This heat is removed from the recycle composition
in another part of the cycle by a cooling system external to the
reactor. Generally, in a gas fluidized bed process for producing
polymers, a gaseous stream containing one or more monomers is
continuously cycled through a fluidized bed in the presence of a
catalyst under reactive conditions. The gaseous stream is withdrawn
from the fluidized bed and recycled back into the reactor.
Simultaneously, polymer product is withdrawn from the reactor and
fresh monomer is added to replace the polymerized monomer. (See for
example U.S. Pat. Nos. 4,543,399, 4,588,790, 5,028,670, 5,317,036,
5,352,749, 5,405,922, 5,436,304, 5,453,471, 5,462,999, 5,616,661
and 5,668,228, all of which are fully incorporated herein by
reference.)
[0086] The reactor pressure in a gas phase process may vary from
about 60 psig (690 kPa) to about 500 psig (3448 kPa), preferably in
the range of from about 200 psig (1379 kPa) to about 400 psig (2759
kPa), more preferably in the range of from about 250 psig (1724
kPa) to about 350 psig (2414 kPa).
[0087] The reactor temperature in a gas phase process may vary from
about 30.degree. C. to about 120.degree. C., preferably from about
60.degree. C. to about 115.degree. C., more preferably in the range
of from about 70.degree. C. to 11 0.degree. C., and most preferably
in the range of from about 70.degree. C. to about 95.degree. C.
[0088] Other gas phase processes contemplated by the process of the
invention include series or multistage polymerization processes.
Also gas phase processes contemplated by the invention include
those described in U.S. Pat. Nos. 5,627,242, 5,665,818 and
5,677,375, and European publications EP-A-0 794 200 EP-B 1-0 649
992, EP-A-0 802 202 and EP-B-634 421 all of which are herein fully
incorporated by reference.
[0089] In a preferred embodiment, the reactor utilized in the
present invention is capable and the process of the invention is
producing greater than 500 lbs of polymer per hour (227 Kg/hr) to
about 200,000 lbs/hr (90,900 Kg/hr) or higher of polymer,
preferably greater than 1000 lbs/hr (455 Kg/hr), more preferably
greater than 10,000 lbs/hr (4540 Kg/hr), even more preferably
greater than 25,000 lbs/hr (11,300 Kg/hr), still more preferably
greater than 35,000 lbs/hr (15,900 Kg/hr), still even more
preferably greater than 50,000 lbs/hr (22,700 Kg/hr) and most
preferably greater than 65,000 lbs/hr (29,000 Kg/hr) to greater
than 100,000 lbs/hr (45,500 Kg/hr).
[0090] A slurry polymerization process generally uses pressures in
the range of from about 1 to about 50 atmospheres and even greater
and temperatures in the range of 0.degree. C. to about 120.degree.
C. In a slurry polymerization, a suspension of solid, particulate
polymer is formed in a liquid polymerization diluent medium to
which ethylene and comonomers and often hydrogen along with
catalyst are added. The suspension including diluent is
intermittently or continuously removed from the reactor where the
volatile components are separated from the polymer and recycled,
optionally after a distillation, to the reactor. The liquid diluent
employed in the polymerization medium is typically an alkane having
from 3 to 7 carbon atoms, preferably a branched alkane. The medium
employed should be liquid under the conditions of polymerization
and relatively inert. When a propane medium is used the process
must be operated above the reaction diluent critical temperature
and pressure. Preferably, a hexane or an isobutane medium is
employed.
[0091] A preferred polymerization technique of the invention is
referred to as a particle form polymerization, or a slurry process
where the temperature is kept below the temperature at which the
polymer goes into solution. Such technique is well known in the
art, and described in for instance U.S. Pat. No. 3,248,179 which is
fully incorporated herein by reference. Other slurry processes
include those employing a loop reactor and those utilizing a
plurality of stirred reactors in series, parallel, or combinations
thereof. Non-limiting examples of slurry processes include
continuous loop or stirred tank processes. Also, other examples of
slurry processes are described in U.S. Pat. No. 4,613,484, which is
herein fully incorporated by reference.
[0092] In an embodiment the reactor used in the slurry process of
the invention is capable of and the process of the invention is
producing greater than 2000 lbs of polymer per hour (907 Kg/hr),
more preferably greater than 5000 lbs/hr (2268 Kg/hr), and most
preferably greater than 10,000 lbs/hr (4540 Kg/hr). In another
embodiment the slurry reactor used in the process of the invention
is producing greater than 15,000 lbs of polymer per hour (6804
Kg/hr), preferably greater than 25,000 lbs/hr (11,340 Kg/hr) to
about 100,000 lbs/hr (45,500 Kg/hr).
[0093] Examples of solution processes are described in U.S. Pat.
Nos. 4,271,060, 5,001,205, 5,236,998 and 5,589,555, which are fully
incorporated herein by reference
[0094] A preferred process of the invention is where the process,
preferably a slurry or gas phase process is operated in the
presence of a bulky ligand metallocene catalyst system of the
invention and in the absence of or essentially free of any
scavengers, such as triethylaluminum, trimethylaluminum,
tri-isobutylaluminum and tri-n-hexylaluminum and diethyl aluminum
chloride, dibutyl zinc and the like. This preferred process is
described in PCT publication WO 96/08520 and U.S. Pat. No.
5,712,352 and 5,763,543, which are herein fully incorporated by
reference.
[0095] Polymer Products
[0096] The polymers produced by the process of the invention can be
used in a wide variety of products and end-use applications. The
polymers produced by the process of the invention include linear
low density polyethylene, elastomers, plastomers, high density
polyethylenes, low density polyethylenes, polypropylene and
polypropylene or polyethylene copolymers.
[0097] The polymers of the invention may be blended and/or
coextruded with any other polymer. Non-limiting examples of other
polymers include linear low density polyethylenes produced via
conventional Ziegler-Natta and/or bulky ligand metallocene
catalysis, elastomers, plastomers, high pressure low density
polyethylene, high density polyethylenes, polypropylenes and the
like.
[0098] The preferred polymers of this invention contain at least
50% polyethylene. Comonomers such as 1-butene, 1-pentane, 1-hexane,
benzylcyclobutante and styrene are preferred. The preferred polymer
product will have a density of from 0.85 to 0.96 g/cc, more
preferably from about 0.88 to 0.96 g/cc and most preferably from
about 0.90 to 0.96 g/cc.
[0099] Polymers produced by the process of the invention and blends
thereof are useful in such forming operations as film, sheet, and
fiber extrusion and co-extrusion as well as blow molding, injection
molding and rotary molding. Films include blown or cast films
formed by coextrusion or by lamination useful as shrink film, cling
film, stretch film, sealing films, oriented films, snack packaging,
heavy duty bags, grocery sacks, baked and frozen food packaging,
medical packaging, industrial liners, membranes, etc. in
food-contact and non-food contact applications. Fibers include melt
spinning, solution spinning and melt blown fiber operations for use
in woven or non-woven form to make filters, diaper fabrics, medical
garments, geotextiles, etc. Extruded articles include medical
tubing, wire and cable coatings, geomembranes, and pond liners.
Molded articles include single and multi-layered constructions in
the form of bottles, tanks, large hollow articles, rigid food
containers and toys, etc.
Examples
[0100] In order to provide a better understanding of the present
invention including representative advantages thereof, the
following examples are offered.
[0101] The Activity values, shown in Table 1, are normalized values
based upon grams of polymer produced per mmol of transition metal
in the catalyst per hour per 100 psi (689 KPa) of ethylene
polymerization pressure.
[0102] 1H NMR spectra were measured by a Bruker AMX 300
[0103] Polydispersity Index (PDI) is equivalent to Molecular Weight
Distribution (Mw/Mn, where Mw is weight average molecular weight
and Mn is number average molecular weight), as determined by gel
permeation chromatography.
[0104] Methylalumoxane (MAO) was used in toluene (30 wt %). (BF-20)
is dimethylanilinium tetra(pentafluorophenyl)borate (BF-20).
Catalyst Component A is 1,3-dimethylcyclopentadienylzirconium
trispivalate and Catalyst Component B is indenylzirconium
trispivalate.
Example 1
Synthesis of (1,3-Dimethylcyclopentadienyl)zirconium trispivalate
(Catalyst Component A)
[0105] To a solution of bis(1,3-dimethylcyclopentadienyl)zirconium
dichloride (1.390 g, 3.99 mmol) and pivalic acid (1.520 g, 14.9
mmol) in toluene at 25.degree. C. was added neat triethylamine
(1.815 g, 18.10 mmol) with stirring. A white precipitate formed
immediately which was removed by filtration. The compound was
isolated as a pale-yellow powder in 88% yield and exhibited purity
above 99% based on NMR results. .sup.1H NMR (toluene-d.sub.8):
65.84 (m, 2H), 5.53 (m, 1H), 2.18 (s, 6H), 1.13 (s, 27H).
Example 2
Preparation of Indenylzirconium Trispivalate (Catalyst Component
B)
[0106] The compound (Ind)Zr(NEt.sub.2).sub.3 (37 mg, 0.088 mmole)
was dissolved in 1.0 mL of benzene-d6. A solution of pivalic acid
(27 mg, 0.26 mmole) in 1.0 mL benzene-d6 was added with stirring.
.sup.1H NMR exhibited resonances assigned to NEt.sub.2H and
(Ind)Zr(O.sub.2 CCMe.sub.3).sub.3. .sup.1H NMR (C.sub.6 D.sub.6) d
7.41 (AA'BB', indenyl, 2H), 6.95 (AA'BB', indenyl, 2H), 6.74 (t,
J=3.3 Hz, 2-indenyl, 1H), 6.39 (d, J=3.3 Hz, 1-indenyl, 2H), 1.10
(s, CH.sub.3, 27H).
Example 3
Polymerization Process
[0107] Utilizing the catalyst compounds prepared in Examples 1 and
2, polyethylene was produced in a slurry phase reactor.
[0108] For each of Component A and B prepared in Examples 1 and 2,
a solution in toluene (0.0036M) was prepared. An aliquot (0.5 ml)
of this solution was added to a 6 ounce (177 ml) bottle containing
an aliquot (0.2 ml) of MAO in toluene (3.15M). An aliquot (0.6 ml)
of indene in toluene (0.0030M) then an aliquot (1.0 ml) of BF-20 in
toluene (0.001 8M) was added to the mixing bottle. Anhydrous
conditions were maintained. The polymerization time for all the
Examples 1 and 2 was 30 minutes. Table 1 below shows the catalyst
composition makeup for Examples 1 and 2.
[0109] The slurry reactor was a 1.65 liter, stainless steel
autoclave equipped with a mechanical agitator. The reactor was
first dried by heating at 96.degree. C. under a stream of dry
nitrogen for 40 minutes. After cooling the reactor to 5 0.degree.
C., 1000 ml of hexane was added and the reactor components were
stirred under a gentle flow of nitrogen. Hexene-1 (20 ml) was added
to the reactor as well as an aliquot of triisobutylaluminum in
hexane (0.5 ml, 0.86M) to act as a scavenger. The temperature of
the reactor was gradually raised to 70.degree. C. and the reactor
was pressured to 150 psi (1034 KPa) with ethylene. The pre-mixed
catalyst solution prepared above was then injected into the reactor
to start the polymerization. Heating was continued until a
polymerization temperature of 85.degree. C. was attained. Unless
otherwise noted, polymerization was continued for 30 minutes,
during which time ethylene was continually added to the reactor to
maintain a constant pressure. At the end of 30 minutes, the reactor
was vented and opened.
[0110] Comparative Example 4-Comparative Runs C1-C6
[0111] In Comparative Runs C1 to C6, polyethylene was produced
under conditions similar to those of Examples 1 and 2 with the
exception that the mixture of indene and BF-20 was not used. The
polymerization time for each run in Example 4 was 30 minutes.
[0112] The catalyst system activity, the molecular weights (Mw and
Mn), the molecular weight distributions (Mw/Mn, also known as PDI)
of various polyethylene made in from the catalyst compounds
prepared in the Examples shown in Table 1. As shown in Table 1, the
catalyst systems of the invention comprising the Group 13 element
containing first modifier and the cycloalkadiene second modifier
possessed significantly higher activity.
1TABLE 1 Example or Indene/Zr BF-20/Zr 1(MAO)/Zr run Catalyst molar
ratio molar ratio molar ratio Activity Mw Mn PDI C1 A -- -- 420
15058 427424 123358 3.5 C2 A -- 1.0 420 14431 395835 142874 2.8 C3
A 1.0 -- 420 66525 364033 122111 3 1 A 1.0 1.0 420 200296 222391
54609 4.1 C4 B -- -- 420 12549 290792 90980 3.2 C5 B -- 1.0 420
14379 295051 102456 2.9 C6 B 1.0 -- 420 28078 412101 166874 2.5 2 B
1.0 1.0 420 99921 207151 58686 3.5
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