CA 02350451 2001-05-10
WO 00/37511 PCT/US99/27502
OLEFIN POLYMERIZATION CATALYST SYSTEM,
POLYMERIZATION PROCESS AND POLYMER THEREFROM
FIELD OF THE INVENTION
This invention relates to olefin polymerization catalyst systems comprising
activators and catalysts based upon transition metal compounds comprising
bidentate ligands containing pyridine or quinoline moieties and mixtures
thereof,
1o polymerization processes using such catalyst systems and polymer produced
therefrom.
BACKGROUND OF THE INVENTION
15 The intense commercialization of metallocene polyolefin catalysts has led
to
widespread interest in the design of non-metallocene, homogeneous catalysts.
This
field is more than an academic curiosity as new, non-metallocene catalysts may
provide an easier pathway to currently available products and may also provide
product and process opportunities which are beyond the capability of
metallocene
20 catalysts. In addition, certain non-cyclopentadienyl ligands may be more
economical due to the relative ease of synthesis of a variety of substituted
analogs.
Thus there is a need in the art for new novel olefin polymerization catalysts
and for
the unique polymers they produce. Further there is a need for catalysts
systems
25 that can be modified easily by the addition of an additive to a single
catalyst to
form a bimodal product. Additionally, there is need for identifying catalysts
that
can produce both unimodal and bimodal polyolefins. This invention identifies a
unique family of catalysts that can be used alone or in combination to produce
unique polyolefins, particularly bimodal polyethylene.
WO 96/23101, WO 97/02298, WO 96/33202 and Furhmann et al, Inorg. Chem.
35:6742-6745 (1996) all disclose nitrogen containing single site like catalyst
systems.
-1-
1- 1- 1 CA 02350451 2001-05-10 rl~bvG~'"'u' s ru a~:i
VV1 tl.V?WV vn'mttlv:l wl,v - i nV. J1.V
USSN 09/103,620, published as w0 9901460 on January 14,1999, discloses the
use of transitioa raetal compotmds comprising bidentate ligeads containing
pyridine or quinoline moieties and mixtures thereof with activators to
polymerize
olefins. In particular [[1-(2-Pyridal)N-1-Methylethyl~-[1 N-2,6-
Diisopmpylphcnyl
Arnidojj[2-Methyl-1-Phenyl-2-Propoxy] Zirconium Dibenzy~ is coaibintd with
modified methyl alumoxane in the gas phase to produce e~htylene hexane
polymers.
We have found tb~at USSN 091103,620 can be modified by the dirxt addition of
as
additive to produce bimodal products from a single catalyst.
1o WO 98/49208 published November 5, 1998 discloses a nitrogen-containing
metal
complex arid its use in the polymerization of 1-olefins. EP-A 1-0 619 325
dixloses
a process for preparing polyoleftns haviag a multimodai or at least bimodal
molecular weight distribution utilizing at least two metallocencs whcteiz: one
~5
metallocene is bridged and a one metalloccae is uubridged.
For US purposes the following references are mentioned: US 4,845,067; US
4,999,327; JP 1126111; US 4,508,842; and UK 1015054.
SUMMARY OF THE IN'VENTIUN
This invention relates to apt olefin polymerization catalyst system comprisi~
at
least one activator and one a~
a) at Ieast two transition metal catalysts based on bidentate ligands
containing pyridine or quinoline moieties, as described below as reprcscated
by
2s formula I, II, III or IV,
b) the pmduct of the combination of an activator and a transition metal
catalyst based oa bidetttate ligands containing pyridine or quinolirie
moieties,
such as those described as represented by formula III or IV, that has been
allowed to react prior to the introduction into the reactor, preferably for at
least
3o I S minutes, and/or
Replacement Page -2-
AMENDED SHEET
a
Og : 11- 1- 1 ! L ~fts~:co ~ tw-.
:CA 02350451 2001-05-10
nv. J I TV ~ ~v J
~VVI 1l.VTrrrn ullr,~~mtvN Lrr~r rmrr :.~ :..
c) the product of combination of an additive and a tramit3on metal catatyst
based on bldGntate liganda containing pyridine or qu~loline moieties, such as
those described below as regnsepted by formula I or II.
Replacement Pale -?a-
AIVIENI3cD SHEET
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WO 00/37511 PCT/US99/27502
This invention further relates to a polymer produced therefrom, particularly
to
a unique polyethylene resins, more preferably bimodal high density
polyethylene resins produced by this invention.
BRIEF SUMMARY OF THE DRAWINGS
Figures 1-5 are plots of the log of weight average molecular weight versus the
dwt/d(logM), a measure of molecular weight distribution for the runs in Table
1.
1o Figures 6 and 7 are the size exclusion chromatography (SEC) graphs for the
runs in
examples 11 and 12.
Figure 8 is the SEC graph of the polymer produced in Example 14.
15 Figure 9 is the SEC Graph from Example 14 of USSN 09/103,620, filed June
23,
1998, (published as WO 99/01460).
DETAILED DESCRIPTION OF THE INVENTION
A. This invention relates in part to olefin polymerization catalyst system
2o comprising at least one activator and at least two transition metal
catalysts based on
bidentate ligands containing pyridine or quinoline moieties. The activator may
be
any known catalyst activator and in one embodiment is an alkyl aluminum, an
alumoxane, a modified alumoxane, a polyalumoxane, a non-coordinating anion, a
Lewis acid, a borane or a mixture thereof.
There are a variety of methods for preparing alumoxane and modified
alumoxanes,
non-limiting examples of which are described in U.S. Patent No. 4,665,208,
4,952,540, 5,091,352, 5,206,199, 5,204,419, 4,874,734, 4,924,018, 4,908,463,
4,968,827, S,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 and 5,731,451 and European
publications EP-A-0 561 476, EP-B1-0 279 586 and EP-A-0 594-218, and PCT
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WO 00/37511 PCT/US99/27502
publication WO 94/10180, all of which are herein fully incorporated by
reference.
Methyl alumoxane, modified methylalumoxane, trisobutyl alumoxane, and
polymethylalumoxane are preferred activators.
Ionizing compounds (non-coordinating anions) may contain an active proton, or
some other cation associated with but not coordinated to or only loosely
coordinated to the remaining ion of the ionizing compound. Such compounds and
the like are described in European publications EP-A-0 570 982, EP-A-0 520
732,
EP-A-0 495 375, EP-A-0 426 637, EP-A-500 944, EP-A-0 277 003 and EP-A-0
io 277 004, and U.S. Patent Nos. 5,153,157, 5,198,401, 5,066,741, 5,206,197,
5,241,025, 5,387,568, 5,384,299 and 5,502,124 and U.S. Patent Application
Serial
No. 08/285,380, filed August 3, 1994, all of which are herein fully
incorporated by
reference. Other activators include those described in PCT publication WO
98/07515 such as tris (2, 2', 2"- nonafluorobiphenyl) fluoroaluminate, which
is
is fully incorporated herein by reference. Combinations of activators are also
contemplated by the invention, for example, alumoxanes and ionizing activators
in
combinations, see for example, PCT publications WO 94/07928 and WO 95/14044
and U.S. Patent Nos. 5,153,157 and 5,453,410 all of which are herein fully
incorporated by reference. Also, methods of activation such as using radiation
and
20 the like are also contemplated as activators for the purposes of this
invention.
In a preferred embodiment, the activator is selected frm the following:
tris(2,2',2"-
nonafluorobiphenyl)fluoroaluminate, alumoxane, triphenyl boron, triethyl
boron,
tri-n-butyl ammonium tetraethylborate, triaryl borane, tri(n-butyl)ammoniuxn
25 tetrakis(pentafluorophenyl)boron or a trisperfluorophenyl boron, or
diehtylaluminum chloride.
In one embodiment, the transition metal catalyst compound based on bidentate
ligands containing pyridine or quinoline moieties is represented by the
formula:
((Z)XA~(1'J))qMQn (I)
-4-
'r :71- 1- 1 ~ X2350451 2001-05-10 773g~a372U-» ,~~+48 89 a:7i~!~4-
EMCHE.'N 06
~~''''V 1 I I . ~T~wl vna ~m sun tmn
where M is a metal selected, from Group 3 to 13 or IraantbanidC and actinide
series of the Periodic Table of Elements; Q is bonded to M and each Q is a
monovalaut, divalent or trivalent aaiou; X and Y are bonded to M; X and Y are
independently carbon or a heteroatom, provided that at least one of X and Y is
a hetcmatom, preferably both X and Y are heteroatoms; Y is contained in a
heoerocycltc ring J, wherie J comprises from 2 to 50 non-hydt'ogen atomvs,
preferably 2 to 30 carbon sterns; Z is bonded to X, where Z comprises 1 to 50
non-hydrogen atoms, preferably 1 to 50 carbon atoms or a silyl group, as alkyl
silyl group such as a tri811cy1 silyl, preferably Z is a cyclic group
containing 3 to
30 atoms, preferably 3 to 30 carbon atoms; t is 0 or 1; when t is l, A is a
bridging group joined to at least one of X, Y or J, preferably X and J; q is 1
or
2; n is the oxidation state of M minus q if Q is a monovatent anion, n is (the
oxidation state of M -q~/'2, if Q is a bivalent anion or n is (flee oxidation
state of
M - q ~3 if Q is a trivalent anion., typically n is as integer from 1 to 4
depending on the oxidation state of M.
In one crnbodiurent, if X is oxygen or sulfur then Z is optional. In another
embodiment, if X is nitrogen or phosphorous thin Z is present. Tn as
embodiment, Z is preferably an aryl gioup, more prcfarably a substitubal aryl
2o group.
In another embodiment, the transition metal catalyst compouads are
represented by the formula:
((ltr",rr?X~(Y'~Rup~~Qa
where M is a metal selected from Group 3 to 13 of the Periodic Table of
Elements,
preferably a Group 4 to 12 transition metal, more preferably a Group 4, 5 or 6
Replacement Page -5-
AMENDED SHEET
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WO 00137511
PCT/US99/27502
transition metal, even more preferably a Group 4 transition metal such as
titanium,
zirconium or hafnium, and most preferably zirconium;
Each Q is bonded to M and each Q is a monovalent, divalent or trivalent anion.
Preferably each Q is independently selected from the group consisting of
halogens,
hydrogen, alkyl, aryl, alkenyl, alkylaryl, arylalkyl, hydrocarboxy or phenoxy
radicals having 1-20 carbon atoms. Each Q may also be amides, phosphides,
sulfides, silylalkyls, diketonates, and carboxylates. Optionally, each Q may
contain one or more heteroatoms, more preferably each Q is selected from the
group consisting of halides, alkyl radicals and arylalkyl radicals. Most
preferably,
each Q is selected from the group consisting of arylalkyl radicals such as
benzyl.
X and Y are both bound to M and are independently carbon or a heteroatom,
provided that at least one of X and Y is a heteroatom, X and Y are preferably
each
heteroatoms, more preferably X and Y are independently selected from the group
consisting of nitrogen, oxygen, sulfur and phosphorous, even more preferably
nitrogen or phosphorous, and most preferably nitrogen;
Y is contained in a heterocyclic ring or ring system J. J contains from 2 to
30
2o carbon atoms, preferably from 2 to 7 carbon atoms, more preferably from 3
to 6
carbon atoms, and most preferably 5 carbon atoms. Optionally, the heterocyclic
ring J containing Y, may contain additional heteroatoms. J may be substituted
with
R" groups that are independently selected from the group consisting of
hydrogen or
linear, branched, cyclic, alkyl radicals, or alkenyl, alkynyl, alkoxy, aryl or
aryloxy
radicals. Also, two or more R" groups may be joined to form a cyclic moiety
such
as an aliphatic or aromatic ring. Preferably R" is hydrogen or an aryl group,
most
preferably R" is hydrogen. When R" is an aryl group and Y is nitrogen, a
quinoline
group is formed. Optionally, an R" may be joined to A;
3o Z is a hydrocarbyl group bonded to X, preferably Z is a hydrocarbyl group
of from
1 to 50 carbon atoms, preferably Z is a cyclic group having from 3 to 30
carbon
-6-
CA 02350451 2001-05-10
~.v..nu~l vw : ~ t - 1- 1 : 1:389:~3720~ +49 89 2:3994-4
dl~ n 1 1 . ~I/11111 Vlti 1.11 1V11 Ll.lf Y II V. J IZV 1 ~ 1
atoms, preferably Z is a substituted or uasnbatituW cyclic group containing
fxom 3
to 30 carbon atoms. optionally Includitrg one or more hetamatoms, more
preferably
Z is en aryl group, most grefersbly a substituted aryl group in anothor
embodiment
Z may be silyl or as alkyl silyl, preferably a tfialkyl silyl;
Z rnay be substituted with R' groups that arc iadepeudeatly selocted from
group
consisting of hydrogen or linear, branched, ahcyl radicals or cyclic alkyl,
alkenyl,
alkynyl or aryl radicals. Also, two or moos R' groups may be joined to form a
cyclic moiety such as an aliphatic or aromatic ring. Preferably R' is an alkyl
group
having from 1 to 20 carbon atoms, more preferably R' is methyl, ethyl, pmpyl,
butyl, peatyl aad the like, including isomers thereof, more pnfarably R' is a
methyl
group, or a primary, secondary or tertiary hydrocarbon, including isopropyl, t-
butyl
and the Iikc, most preferably R' is an isopropyl group. Optionally, an R'
group may
be joined to A. It is preferred that at least one R' is ortho to X;
IS
A is a bridging gmup joined to at least one ot, preferably both of, X and 7.
Bridging group A contains one or morn Group 13 to 16 elements from Periodic
Table of Elemeats. More preferably A contains ono or more Group 14 elements,
most preferably A, is a substituted carbon group, a di-substituted carboy
8,roup or
2o vinyl group; and
In formula (II) rn and p are independently an integer from 0 to 5, preferably
m
is 2; n is the oxidation state of M minus Q if Q is a monovalcnt anion, n is
(the
oxidation state of M -q~2, if Q is a bivalent anion or n is (the oxidation
state of
25 M - qx3 if Q is a trivalent anion, preferably n is an integer from 1 to 4;
and q is
1 or 2, and where q is 2, the two ((R'mZ~.4(YJR"~,)) of fommla (II) are
bridged to each other via a bridging group, preferably a bridging group
containing a Group 14 element.
3o In a preferred embodiment when n is 2 or 3 in formula I or II, then the
second
catalyst is the same as the first catalyst except that one Q group is a
Replacement Page -7-
~,lvILiVIJ't~ ~HEE~I~
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PCTIUS99/27502
WO 00/37511
hydrocarboxy group, a boronate or an amide. In a particularly preferred
embodiment when n is 2 or 3 in formula I or II, then the second catalyst is
the
same as the first catalyst except that one Q group is an alkoxide, phenoxide,
acetylacetonate, carboxylate, cyclopentadienyl, flourenyls or an indenyl
group.
In another particularly preferred embodiment when n is 2 or 3 in formula I or
II
the second catalyst is the same as the first catalyst except that one Q group
of
the second catalyst is a hydrocarboxy adduct of the analogous Q group on the
first catalyst, preferably an alkoxide adduct, a boronate, a phenoxide adduct,
an
acetylacetonate adduct, a carboxylate adduct, an amide adduct, a
to cyclopentadienyl adduct, a flourenyl adduct or an indenyl adduct.
In preferred embodiment, at least one of the transition metal catalyst
compounds is represented by the formula:
((Z)XAt(YJ))qMQmTs (III)
where M is a metal selected from Group 3 to 13 or lanthanide and actinide
series of the Periodic Table of Elements; T is bonded to M and is an element
from Group 13 to 16, preferably oxygen, boron, nitrogen, silicon, phosphorus,
2o sulfur or aluminum and T may also be bound to one or more C 1 to C50 groups
optionally containing one or more heteroatoms, preferably T is a hydrocarboxy
group, a boronate group or an amide group, preferably an alkoxide, phenoxide,
acetylacetonate, or carboxylate or a cyclopentadienide group such as
cyclopentadienyls, flourenyls and indenyls, Q is bonded to M and each Q is a
monovalent, divalent or trivalent anion; X and Y are bonded to M; X and Y are
independently C or a heteroatom, provided that at least one of X and Y is a
heteroatom, preferably both X and Y are heteroatoms; Y is contained in a
heterocyclic ring J, where J comprises from 2 to 50 non-hydrogen atoms,
preferably 2 to 30 carbon atoms; Z is bonded to X, where Z comprises 1 to SO
3o non-hydrogen atoms, preferably 1 to 50 carbon atoms, preferably Z is a
cyclic
group containing 3 to 50 atoms, preferably 3 to 30 carbon atoms, alternately Z
_g_
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PCT/US99/27502
may be a silyl group, preferably an alkyl silyl group; t is 0 or 1; when t is
1, A
is a bridging group joined to at least one of X, Y or J, preferably X and J; q
is 1
or 2; m is the oxidation state of M minus q minus s if Q is a monovalent
anion,
m is (the oxidation state of M -q-s)~2, if Q is a bivalent anion or m is (the
oxidation state of M - q-s)/3 if Q is a trivalent anion, preferably m is an
integer
from 1 to 3, s is 1, 2 or 3, preferably 1 or 2. In one embodiment, where X is
oxygen or sulfur then Z is optional. In another embodiment, where X is
nitrogen or phosphorous then Z is present. In a preferred embodiment T is
oxygen and is bound to an alkyl, aryl, or alkaryl group.
to
In another embodiment, at least one of the transition metal catalyst compounds
is represented by the formula:
((R~mZ)~(YJR"p))qMQ~Ts (IV)
where M is a metal selected from Group 3 to 13 of the Periodic Table of
Elements,
preferably a Group 4 to 12 transition metal, more preferably a Group 4, 5 or 6
transition metal, even more preferably a Group 4 transition metal such as
titanium,
zirconium or hafnium, and most preferably zirconium;
T is bonded to M and is an element from Group 13 to 16, preferably oxygen,
boron, nitrogen, silicon, phosphorus, sulfur or aluminum and T may also be
bound
to one or more C1 to C50 groups optionally containing one or more heteroatoms,
T
is preferably a hydrocarboxy group, a boronate, or an amide, preferably an
alkoxide, phenoxide, acetylacetonate, or carboxylate or a cyclopentadienide
group
such as cyclopentadienyls, flourenyls and indenyls.
Each Q is bonded to M and each Q is a monovalent, divalent or trivalent anion.
Preferably each Q is independently selected from the group consisting of
halogens,
3o hydrogen, alkyl, aryl, alkenyl, alkylaryl, arylalkyl, hydrocarboxy or
phenoxy
radicals having 1-20 carbon atoms. Each Q may also be amides, phosphides,
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_ WO 001,7511
PCT/US99/27502
sulfides, silylalkyls, diketonates, arid carboxylates. Optionally, each Q may
contain one or more heteroatoms, more preferably each Q is selected from the
group consisting of halides, alkyl radicals and arylalkyl radicals. Most
preferably,
each Q is selected from the group consisting of arylalkyl radicals such as
benzyl.
X and Y are independently C or a heteroatom, provided that at least one of X
and
Y is a heteroatom, X and Y are preferably each heteroatoms, more preferably
independently selected from the group consisting of nitrogen, oxygen, sulfur
and
phosphorous, even more preferably nitrogen or phosphorous, and most preferably
nitrogen;
Y is contained in a heterocyclic ring or ring system J. J contains from 2 to
30
carbon atoms, preferably from 2 to 7 carbon atoms, more preferably from 3 to 6
carbon atoms, and most preferably 5 carbon atoms. Optionally, the heterocyclic
ring J containing Y, may contain additional heteroatoms. J may be substituted
with
R" groups that are independently selected from the group consisting of
hydrogen or
linear, branched, cyclic, alkyl radicals, or alkenyl, alkynyl, alkoxy, aryl or
aryloxy
radicals. Also, two or more R" groups may be joined to form a cyclic moiety
such
as an aliphatic or aromatic ring. Preferably R" is hydrogen or an aryl group,
most
2o preferably R" is hydrogen. When R" is an aryl group and Y is nitrogen, a
quinoline
group is formed. Optionally, an R" may be joined to A;
Z is a hydrocarbyl group bonded to X, preferably Z is a hydrocarbyl group of
from
1 to 50 carbon atoms, preferably Z is a cyclic group having from 3 to 30
carbon
atoms, preferably Z is a substituted or unsubstituted cyclic group containing
from 3
to 30 carbon atoms, optionally including one or more heteroatoms, Z may be a
silyl
group, an alkylsilyl group or a trialkyl, in another embodiment Z is not an
aryl
group;
3o Z may be substituted with R' groups that are independently selected from
group
consisting of hydrogen or linear, branched, alkyl radicals or cyclic alkyl,
alkenyl,
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WO 00137511 PCT/US99/27502
or alkynyl radicals. Also, two or more R' groups may be joined to form a
cyclic
moiety such as an aliphatic or aromatic ring. Preferably R' is an alkyl group
having
from 1 to 20 carbon atoms, more preferably R' is methyl, ethyl, propyl, butyl,
pentyl and the like, including isomers thereof, more preferably R' is a methyl
group
or a primary, secondary or tertiary hydrocarbon, including isopropyl, t-butyl
and
the like, most preferably R' is an isopropyl group. Optionally, an R' group
may be
joined to A. It is preferred that at least one R' is ortho to X;
A is a bridging group joined to at least one of, preferably both of, X and J.
to Bridging group A contains one or more Group 13 to 16 elements from Periodic
Table of Elements. More preferably A contains one or more Group 14 elements,
most preferably A is a substituted carbon group, a di-substituted carbon group
or
vinyl group; and
15 In formula (IV) m and p are independently an integer from 0 to 5,
preferably m is
2; s is an integer from 1 to 3; and q is 1 or 2, n is the oxidation state of M
minus q
minus s if Q is a monovalent anion, n is (the oxidation state of M -q-s)/2, if
Q is a
bivalent anion or n is (the oxidation state of M - q - s)/3 if Q is a
trivalent anion,
and where q is 2, the two ((R'mZ)XA(YJR"rn)) of formula (IV) are bridged to
each
20 other via a bridging group, preferably a bridging group containing a Group
14
element.
In one embodiment J is pyridine in any of the above formulae.
25 The transition metal compounds may be made by any method known in the art.
For example, USSN 09/103,620, filed June 23, 1998 claiming priority from
provisional application number 60/051,581 filed July 2, 1997, now published as
WO 99/01460, discloses methods to produce these compounds.
3o In a preferred embodiment the transition metal compound is [[1-(2-Pyridal)N-
1-
Methylethyl]-[1-N-2,6-Diisopropylphenyl Amido])[2-Methyl-1-Phenyl-2-Propoxy]
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WO 00/37511 PCT/US99/27502
Zirconium Dibenzyl. In another preferred embodiment [[1-(2-Pyridal)N-1-
Methylethyl]-[1-N-2,6-Diisopropylphenyl Amido]][2-Methyl-1-Phenyl-2-Propoxy]
Zirconium Dibenzyl is used in combination with an alumoxane, preferably
methylalumoxane, more preferably a modified methyl alumoxane in a gas or
slurry
phase reactor to produce polyethylene, preferably high density polyethylene.
In
another prefered embodiment a non-coordination anion, such as tri(n-
butyl)ammonium tetrakis (pentafluorophenyl)boron or trisperfluorophenyl boron,
is
used in combination with the [[1-(2-Pyridal)N-1-Methylethyl]-[1-N-2,6-
Diisopropylphenyl Amido]][2-Methyl-1-Phenyl-2-Propoxy] Zirconium Dibenzyl in
to a gas or slurry phase reactor. In another embodiment that activator is
selected from
the following: tris (2,2',2"- nonafluorobiphenyl) fluoroaluminate, alumoxane,
triphenyl boron, triethyl boron, tri-n-butyl ammonium tetraethylborate,
triaryl
borate, tri(n-butyl) ammonium tetrakis (pentafluorophenyl) boron, or a
trisperfluorophenyl boron, or diethylaluminum chloride.
In one embodiment, in the practice if this invention, two or more catalysts
are
selected to produce the desired product. The two or more catalysts are
selected
from any of the above formulae. For example two different catalyst form
formula I
may be selected, or a compound from formula I or II and a compound from
2o formula III or IV can be combined. Likewise, two different catalysts
falling within
the definition of formula IV may be combined. In a preferred embodiment a
compound from formula I or II is used together with at lease one compound from
formulae III or IV. It is possible to obtain a bimodal product by selecting
catalysts
that are know to produce differing molecular weights.
In another embodiment the two catalysts are fed into the reactor separately.
In a preferred embodiment a first catalyst as represented by formula I or II
where at
least one Q group is not an oxy-adduct is chosen and the second catalyst is
the
3o same as the first catalyst system except that one, two or all three of the
Q groups is
an oxy-adduct of the same Q group as is present in the first catalyst. For
example
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if [1-(2-Pyridyl)N-1-Methylethyl][1-N-2,6-Diisopropylphenyl Amido] Zirconium
Tribenzyl is selected as the first catalyst, them [[1-(2-Pyridyl)N-1-
Methylethyl]-
[1-N-2,6-Diisopropylphenyl Amido]][2-Methyl-1-Phenyl-2-Propoxy] Zirconium
Dibenzyl may be a second catalyst.
For purposes of this invention and the claims thereto oxy-adduct is defined to
be O-
R where O is oxygen and R is a C, to Cso group which optionally may contain
one
or more heteroatoms. Preferred R groups include t-butyl, t-amyl, t-hexyl,
isopropyl, 2-[2-methyl-1-phenyl-propyl], 2-[2-benzyl-butyl], 3-[3-benzyl-
pentyl].
1o Other possible R groups include benzyl, methyl benzyl, ethyl benzyl and the
like.
In another embodiment the oxy adduct may be represented by the formula O-B-R,
where O is oxygen, B is boron and R is a C~ to CSO group which optionally may
contain one or more heteroatoms. Preferred R groups include t-butyl, t-amyl, t-
hexyl, isopropyl, 2-[2-methyl-1-phenyl-propyl], 2-[2-benzyl-butyl], 3-[3-
benzyl-
ts pentyl]. Other possible R groups include, benzyl, methyl benzyl, ethyl
benzyl and
the like.
In a preferred embodiment the two catalysts, [1-(2-Pyridyl)N-1-Methylethyl][1-
N-
2,6-Diisopropylphenyl Amido] Zirconium Tribenzyl and [[1-(2-Pyridyl)N-1-
20 Methylethyl]-[1-N-2,6-Diisopropylphenyl Amido]][2-Methyl-1-Phenyl-2-
Propoxy]
Zirconium Dibenzyl, are used in combination with an alumoxane, preferably a
methyl alumoxane, more preferably a modified methyl alumoxane in a gas phase
or
slurry reactor to produce polyethylene, preferably high density polyethylene
or
alternately low density polyethylene. In another preferred embodiment a non-
25 coordinating anion, such as tri (n-butyl) ammonium tetrakis
(pentafluorophenyl)
boron or a trisperfluorophenyl boron, is used in combination with the two
catalysts,
[1-(2-Pyridyl}N-1-Methylethyl][1-N-2,6-Diisopropylphenyl Amido] Zirconium
Tribenzyl and [[1-(2-Pyridyl)N-1-Methylethyl]-[1-N-2,6-Diisopropylphenyl
Amido]][2-Methyl-1-Phenyl-2-Propoxy] Zirconium Dibenzyl, in a gas phase or
3o slurry phase reactor to produce polyolefin, preferably polyethylene.
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In a preferred embodiment, the two catalyst compounds are typically combined
in a
ratio of from 0.001:1 to about 10,000:1, preferably 0.5:1 to 1,000:1. In a
preferred
embodiment the first catalyst is present at from about 0.5 to about 99.5
weight
and the second catalyst is preset at about 99.5 to about 0.5 weight %, based
upon
the weight of the two catalysts but not activators or supports, preferably 5
to 95
weight % first catalyst and 95 to 5 weight % for the second catalyst,
preferably 10
to 90 weight % first catalyst and 90 to 10 weight % for the second catalyst.
In a preferred embodiment the first catalyst is present at from about 0.5 to
about
Io 99.5 weight % and the second and third catalysts are preset at about 99.5
to about
0.5 weight %, based upon the weight of the three catalysts but not actW ators
or
supports, preferably 5 to 95 weight % first catalyst, preferably 10 to 90
weight
first catalyst.
15 B. This invention further relates to olefin polymerization catalyst systems
comprising at least one activator and the product of the combination of an
activator
(as described above) and a transition metal catalyst represented by formula
III or
IV (as described above), that has been allowed to react prior to introduction
into the
reactor, preferably for at least 15 minutes. In such an embodiment a single
2o transition metal compound represented by the formulae III or IV can be used
to
produce unique, preferably bimodal, polyolefins. It has been observed that
temperature apparently affects the catalysts represented by formula III or IV
and
apparently produces additional species. While not wishing to be bound by any
theory, it appears that this conversion provides the ability to produce bi-
modal
25 product. Thus we have noted that higher temperatures produce more bimodal
product from catalysts systems where one transition metal compound was used in
the catalysts preparation. Similarly it has been observed that allowing the
transition metal compound and the activator to react for a period of time also
provides a system that can produce bimodal or mufti-modal polymer. Thus in a
3o preferred embodiment the transition metal compound and the activator are
allowed
to reactor for at least 15 minutes prior to being contacted with olefin,
preferably at
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least 30 minutes, preferably at least 1 hour, preferably at least 4 hours. We
have
however also noted that split second activation of [1-(2-Pyridyl)N-1-
Methylethyl][1-N-2,6-Diisopropylphenyl Amido] Zirconium Tribenzyl just before
it was sprayed into the reactor produced a very active catalyst system that
also
apparently produced a bimodal resin. In another embodiment the polymerization
preferably occurs at a temperature of at least 80 °C, preferably at
least 85°C,
preferably at least 90°C, preferably at least 100 °C.
C. This invention further relates to an olefin polymerization catalyst
to system comprising at least one activator (as described above) and the
product
of combination of an additive and a transition metal catalyst based on
bidentate
ligands containing pyridine or quinoline moieties represented by formula I or
II
(as described above).
The additive is preferably an alkoxy compound. Alkoxy compound is defined to
be compounds represented by the formula R=O where R is a C~ to C» group and
the oxygen may be bound at any point along the R group. The R group may also
contain heteroatoms, in addition to the 1 to 100 carbon atoms. Preferred
alkoxy
compounds include ketones and aldehydes. Particularly preferred alkoxy
2o compounds include acetone, benzophenone, methyl ethyl ketone, diethyl
ketone,
methyl isobutyl ketone, methyl isopropyl ketone, diisopropyl ketone, methyl
tertiary butyl ketone, acetophenone, cyclohexanone, cyclopentanone,
benzaldehyde, pivaldehyde, ethyl n-propyl ketone, ethyl isopropyl ketone, and
the
like.
In a preferred embodiment the additive is combined with the transition metal
catalyst compound in an amount of 0.5 weight % to about 90 weight % based upon
the weight of the transition metal catalyst compound and the additive, but not
any
activators or supports, preferably 1 weight % to about 80 weight %, more
3o preferably 10 to 60 weight %. The additive may be combined with the
transition
metal catalyst compound (with or without the activator) before being added to
the
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polymerization reactor. In one embodiment the additive is added to the
transition
metal catalyst compound in line in the injection tube.
In a preferred embodiment the activator is allowed to react with the
transition metal
catalyst compound (that has already been reacted with the additive) for at
least 5
minutes before being combined with the olefin, preferably 10 minutes, more
preferably 15 minutes. It has been noted that if the transition metal catalyst
compound is simply combined with the additive then added directly to the
reactor,
that less bimodal product is obtained. If the additive and the transition
metal
1o compound are allowed to react then for a period of time then more bimodal
product
is obtained.
In a preferred embodiment the additive and the transition metal catalyst
compound
are combined prior to being combined with the activator. In a alternative
15 embodiment the transition metal catalyst, olefin and the activator are
already
present in the polymerization reactor and the additive is added. In
embodiments
where the additive is to be added after the activator and the transition metal
catalyst
compound are already combined and the activator is alumoxane, then extra
amounts of additive may be required.
Different additives may be used to achieve different effects on the polymer
produced. For example using diethyl ketone as the additive produces a polymer
having a higher molecular weight than does using methyl ethyl ketone as the
additive. Likewise using methyl ethyl ketone as the additive produces a
polymer
having a higher molecular weight than using acetone as the additive does.
In a preferred embodiment the transition metal catalyst compound, [1-(2-
Pyridyl)N-1-Methylethyl][1-N-2, 6-Diisopropylphenyl Amido] Zirconium
Tribenzyl and the additive acetone are used in combination with an alumoxane,
3o preferably a methyl alumoxane, more preferably a modified methyl alumoxane
in a
gas phase or slurry reactor to produce polyethylene, preferably high density
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polyethylene. In another preferred embodiment a non-coordinating anion, such
as
tri (n-butyl} ammonium tetrakis (pentafluorophenyl) boron or a
trisperfluorophenyl
boron, is used in combination with the transition metal catalyst compound, [1-
(2-
Pyridyl)N-1-Methylethyl][1-N-2,6-Diisopropylphenyl Amido] Zirconium
Tribenzyl and acetone, in a gas phase or slurry phase reactor.
The additive may or may not be present when the activator is added to the
transition 15 metal compound before or after being placed in the reactor. In
another preferred embodiment two different transition metal compounds are used
l0 in combination with an activator and an additive in the same reactor. In
another
preferred embodiment the transition metal catalyst compound and activator are
fed
into the reactor separately from the additive. While not wishing to be bound
by
any theory, it appears that the additive reacts with the transition metal
catalyst
compound to provide another active catalyst species. In embodiments of the
15 invention, it has been noted that temperature appears to affect the balance
between
the two forms of the catalyst. It seems that higher temperatures may drive the
conversion of the transition metal catalyst compound in the presence of the
additive
to the second catalyst species. Thus by selecting the amount of additive and
the
temperature at which they are combined and/or used one can select for desired
end
20 products.
In a preferred embodiment the catalyst component that produces the lower
molecular weight is present at 10 ppm to 70 weight % based upon the weight of
all
the catalysts but not the activators or supports, preferably 100 ppm to 8
weight %,
25 even more preferably 1000 ppm to 5 weight %. In another embodiment the
compound that produces the lower molecular weight is present at 30 to 70
weight
based upon the weight of all the catalysts but not the activators or supports,
preferably 40 to 60 weight %, even more preferably 45 to 55 weight %.
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In another embodiment, the component that makes the low molecular weight
portion is present is an amount that will produce 20-70 weight % of the final
polymer product.
If multiple catalysts are used then the two or more catalysts may be activated
at the
same or different times, before or after entry into the reactor, and before or
after
being placed on a support. In one embodiment the multiple catalysts are
activated
by the same activator before being placed in the reactor. In another
embodiment,
one catalyst is activated before being placed in the reactor, and a second
catalyst is
1o added, optionally with no activator, the same activator or a different
activator. In
another embodiment the catalysts are supported on the same support then
activated
with the same activator prior to being placed in the reactor. In another
embodiment
the two catalysts are activated with the same or different activators then
placed
upon a support before being placed in the reactor.
Likewise, one or more of the catalyst systems or components may be supported
on
an organic or inorganic support. Typically the support can be of any of the
solid,
porous supports. Typical support materials include talc; inorganic oxides such
as
silica, magnesium chloride, alumina, silica-alumina; polymeric supports such
as
2o polyethylene, polypropylene, polystyrene; and the like. Preferred supports
include
silica, clay, talc, magnesium chloride and the like. Preferably the support is
used
in finely divided form. Prior to use the support is preferably partially or
completely dehydrated. The dehydration may be done physically by calcining or
by chemically converting all or part of the active hydroxyls. For more
information on how to support catalysts please see US 4,808,561 which teaches
how to support a metallocene catalyst system. The techniques used therein are
generally applicable for this invention.
The catalysts may be placed on separate supports or may be placed on the same
3o support. Likewise the activator may be placed on the same support as the
catalyst
or may be placed on a separate support. The catalysts/catalyst systems and/or
their
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components need not be feed into the reactor in the same manner. For example,
one catalyst or its components may be slurried into the reactor on a support
while
the other catalyst or components may be provided in a solution.
In a preferred embodiment the catalyst system is fed into the reactor in a
solution or
slurry. Hydrocarbons are useful for the solutions or slurries. For example the
solution can be toluene, hexane, isopentane or a combination thereof such as
toluene and isopentane or toluene and pentane. A typical solution would be
0.02 to
0.05 mole catalyst in the hydrocarbon carrier, preferably isopentane or
hexane.
In another embodiment the carrier for the catalyst system or its components is
a
super critical fluid, such as ethane or propane. For more information on
supercritical fluids as catalyst feed agents see EP 0 764 665 A2.
In another preferred embodiment the one or all of the catalysts are combined
with
up to 6 weight % of a metal stearate, (preferably a aluminum stearate, more
preferably aluminum distearate) based upon the weight of the catalyst, any
support
and the stearate, preferably 2 to 3 weight %. In an alternate embodiment a
solution
of the metal stearate is fed into the reactor. These agents may be dry tumbled
with
the catalyst or may be fed into the reactor in a solution with or without the
catalyst
system or its components. In a preferred embodiment the catalysts combined
with
the activators are tumbled with 1 weight % of aluminum distearate and/or 2
weight
of an antistat, such as a methoxylated amine, such as Witco's Kemamine AS
990 from ICI Specialties in Bloomington Delaware. The metal stearate and/or
the
anti-static agent may be slurned into the reactor in mineral oil, ground into
a
powder then suspended in mineral oil then fed into the reactor, or blown
directly
into the reactor as a powder.
More information on using aluminum stearate type additives may be found in
3o USSN 09/113,216 filed July 10,1998, which is incorporated by reference
herein.
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wo oor~~si ~ PcT~s99mso2
POLYMERIZATION PROCESS OF THE INVENTION
The catalysts and catalyst systems described above are suitable for use in a
solution, gas or slurry polymerization process or a combination thereof, most
preferably a gas or slurry phase polymerization process.
In one embodiment, this invention is directed toward the solution, slurry or
gas
phase polymerization reactions involving the polymerization of one or more of
monomers having from 2 to 30 carbon atoms, preferably 2-12 carbon atoms, and
1o more preferably 2 to 8 carbon atoms. Preferred monomers include one or more
of
ethylene, propylene, butene-1, pentene-1, 4-methyl-pentene-1, hexene-1, octene-
1,
decene-1, 3-methyl-pentene-1, and cyclic olefins or a combination thereof.
Other
monomers can include vinyl monomers, diolefins such as dienes, polyenes,
norbornene, norbornadiene, vinyl norbornene, ethylidene norbornene monomers.
15 Preferably a homopolymer of ethylene is produced. In another embodiment, a
copolymer of ethylene and one or more of the monomers listed above is
produced.
In another embodiment ethylene or propylene is polymerized with at least two
different comonomers to form a terpolymer. The preferred comonomers are a
20 combination of alpha-olefin monomers having 4 to 10 carbon atoms, more
preferably 4 to 8 carbon atoms, optionally with at least one dime monomer. The
preferred terpolymers include the combinations such as ethylene/butene-
1/hexene-
1, ethylene/propylene/butene-1, propylene/ethylene/hexene-1,
ethylene/propylenel
norbornene and the like.
In a particularly preferred embodiment the process of the invention relates to
the
polymerization of ethylene and at least one comonomer having from 4 to 8
carbon
atoms, preferably 4 to 7 carbon atoms. Particularly, the comonomers are butene-
1,
4-methyl-pentene-1,3-methyl-pentene-1, hexene-1 and octene-1, the most
preferred
being hexene-1, butene-1 and octene-1.
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Typically in a gas phase polymerization process a continuous cycle is employed
where in 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
l0 is withdrawn from the reactor and fresh monomer is added to replace the
polymerized monomer. (See for example U.S. Patent 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.)
15 The reactor pressure in a gas phase process may vary from about 10 psig (69
kPa)
to about 500 psig (3448 kPa), preferably from about 100 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).
The reactor temperature in the gas phase process may vary from about
30°C to
about 120°C, preferably from about 60°C to about 115°C,
more preferably in the
range of from about 70°C to 110°C, and most preferably in the
range of from about
70°C to about 95°C. In another embodiment when high density
polyethylene is
desired then the reactor temperature is typically between 70 and 105
°C.
The productivity of the catalyst or catalyst system in a gas phase system is
influenced by the main monomer partial pressure. The preferred mole percent of
the main monomer, ethylene or propylene, preferably ethylene, is from about 25
to
90 mole percent and the comonomer partial pressure is in the range of from
about
20 Asia (138 kPa) to about 300 psia (517kPa), preferably about 75 psia (5.17
kPa) to
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about 300 psia (2069 kPa), which are typical conditions in a gas phase
polymerization process. Also in some systems the presence of comonomer can
provide a increase in productivity.
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 preferably
greater than 65,000 lbs/hr (29,000 Kg/hr) to greater than 100,000 lbs/hr
(45,500
Kg/hr), and most preferably over 100,000 Ibslhr ( 45,500 Kg/hr).
Other gas phase processes contemplated by the process of the invention include
those described in U.S. Patent Nos. 5,627,242, 5,665,818 and 5,677,375, and
European publications EP-A- 0 794 200, EP-A- 0 802 202 and EP-B- 634 421 all
of which are herein fully incorporated by reference.
A slurry polymerization process generally uses pressures in the range of from
about
1 to about 50 atmospheres (15 psi to 735 psi, 103 kPa to 5068 kPa) and even
greater and temperatures in the range of 0°C to about 120°C. In
a slurry
polymerization, a suspension of solid, particulate polymer is formed in a
liquid
polymerization diluent medium to which ethylene and comonomers 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
3o medium employed should be liquid under the conditions of polymerization and
relatively inert. When a propane medium is used the process must be operated
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above the reaction diluent critical temperature and pressure. Preferably, a
hexane
or an isobutane medium is employed.
In one embodiment, 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.
Patent
No. 3,248,179 which is fully incorporated herein by reference. The preferred
temperature in the particle form process is within the range of about
185°F (85°C)
to about 230°F (110°C}. Two preferred polymerization methods for
the slurry
process are 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. Patent No. 4,613,484, which
is
herein fully incorporated by reference.
In another embodiment, the slurry process is carried out continuously in a
loop
reactor. The catalyst as a slurry in isobutane or as a dry free flowing powder
is
injected regularly to the reactor loop, which is itself filled with
circulating slurry of
2o growing polymer particles in a diluent of isobutane containing monomer and
comonomer. Hydrogen, optionally, may be added as a molecular weight control.
The reactor is maintained at a pressure of about 525 psig to 625 psig (3620
kPa to
4309 kPa) and at a temperature in the range of about 140 °F to about
220 °F (about
60 °C to about 104 °C) depending on the desired polymer density.
Reaction heat is
removed through the loop wall since much of the reactor is in the form of a
double-
jacketed pipe. The slurry is allowed to exit the reactor at regular intervals
or
continuously to a heated low pressure flash vessel, rotary dryer and a
nitrogen
purge column in sequence for removal of the isobutane diluent and all
unreacted
monomer and comonomers. The resulting hydrocarbon free powder is then
compounded for use in various applications.
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In another 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 lbslhr (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).
In another embodiment in the slurry process of the invention the total reactor
to pressure is in the range of from 400 psig (2758 kPa) to 800 psig (5516
kPa),
preferably 450 psig (3103 kPa) to about 700 psig (4827 kPa), more preferably
500
psig (3448 kPa) to about 650 psig (4482 kPa), most preferably from about 525
psig
(3620 kPa) to 625 psig (4309 kPa).
is In yet another embodiment in the slurry process of the invention the
concentration
of ethylene in the reactor liquid medium is in the range of from about 1 to 10
weight percent, preferably from about 2 to about 7 weight percent, more
preferably
from about 2.5 to about 6 weight percent, most preferably from about 3 to
about 6
weight percent.
Another process of the invention is where the process, preferably a slurry or
gas
phase process is operated 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
process is described in PCT publication WO 96/08520 and U.S. Patent No.
5,712,352, which are herein fully incorporated by reference.
In another embodiment the process is run with scavengers. Typical scavengers
include trimethyl aluminum, tri-isobutyl aluminum and an excess of alumoxane
or
3o modified alumoxane.
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The proportions of the components of the feed catalyst solution can be varied
to
alter molecular weight and other properties. For example altering the catalyst
ratios will alter flow index, melt index, melt flow ratio and/or density. For
example, in a system where a catalyst represented by formula I and a catalyst
represented by formula IV are combined, if the proportion of a catalyst
represented
by formula IV is increased then, more lower molecular weight material is
produced
thus increasing flow index, altering the molecular weight distribution. In a
preferred embodiment the catalyst that produces the lower molecular weight
component is present at a value to produce 45-65 weight % of the final polymer
to product. For some applications such as films the combination of 55-35
weight
of (A). [1-(2-Pyridyl)N-1-Methylethyl][1-N-2,6-Diisopropylphenyl Amido]
Zirconium Tribenzyl and 45-65 weight % of (B). [[1-(2-Pyridyl)N-1-Methylethyl]-
[1-N-2,6-Diisopropylphenyl Amido]][2-Methyl-1-Phenyl-2-Propoxy] Zirconium
Dibenzyl has been found effective.
Another method to alter the molecular weight is to add hydrogen to the system
by
increasing the hydrogen ethylene ratio. A method to control the density is
altering
the comonomer content.
2o A method to control molecular weight distribution (Mw/Mn), flow index,
and/or
density comprising altering on line in a commercial scale gas phase reactor
(i.e.
having a volume of 1500 cubic feet (42.5 m3)or more) the reaction temp and/or
the
catalyst ratio in the intimately mixed catalyst solution and/or the hydrogen
concentration and/or the activator to transition metal ratio, such as the
aluminum/zirconium ratio is also provided herein.
Injection and mixing temperatures also provide a means to alter product
properties
as temperature affects activation and/or solvent evaporation and thus alters
the
catalyst composition and hence alters the final product.
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The sequence and timing of activation also provides an opportunity to alter
the
catalyst composition and thus the final product. For example higher
concentrations
of methyl alumoxane in a system comprising (A). [1-(2-Pyridyl)N-1-
Methylethyl][1-N-2,6-Diisopropylphenyl Amido] Zirconium Tribenzyl and (B).
[[1-(2-Pyridyl)N-1-Methylethyl]-[1-N-2,6-Diisopropylphenyl Amido]][2-Methyl-
1-Phenyl-2-Propoxy] Zirconium Dibenzyl will alter the balance of products
formed
by the two catalysts. This includes higher concentrations during activation
and/or
mixing and/or transport andlor in spraying into the reactor. Likewise we have
noted that increasing the hydrocarbon Garner in the catalyst feed increased
the
1o amount of lower molecular weight fraction produced.
One can also vary the product by altering the reaction temperature. We have
noted
that raising the reaction temperature increased the amount of the higher
molecular
weight component and unusually the two modes in the size exclusion
~ 5 chromatography graph moved closer together (that is the Mw/Mn became lower
when compared to the same system at a lower temperature).
One can also vary the molecular weight distribution by varying the reactor
temperature, varying the temperature of the catalyst system before it enters
the
2o reactor, varying the catalyst to activator ratio, varying the volume of the
carrier,
and/or contacting the transition metal component with solvent prior to
activation
with the activator.
In a preferred embodiment the ratio of the first catalyst to the second or
additional
25 catalyst is 5:95 to 95:5, preferably 25:75 to 75:25, even more preferably
40:60 to
60:40.
In another preferred embodiment the catalyst system in is liquid form and is
introduced into the reactor into a resin particle lean zone. For information
on how
3o to introduce a liquid catalyst system into a fluidized bed polymerization
mto a
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particle lean zone, please see US 5,693,727, which is incorporated by
reference
herein.
An example of a typical polymerization is: Modified methylalumoxane in
hydrocarbon such as hexane or isopentane (about 1 to 10 % aluminum) and 10-30
weight % of [1-(2-Pyridyl)N- 1 -Methylethyl] [1-N-2,6-Diisopropylphenyl
Ainido]
Zirconium Tribenzyl and 70-90 weight% of [[1-(2-Pyridyl)N-1-Methylethyl]-[1-N-
2,6-Diisopropylphenyl Amido]][2-Methyl-1-Phenyl-2-Propoxy] Zirconium
Dibenzyl, are suspended in solution then dried, thereafter they are tumbled
with 2
1o weight % aluminum distearate and then slurried into a fluidized bed gas
phase
reactor held at a temperature of about 85 to about 100°C in an Al to Zr
ratio of
about 500:1 to about 1000:1, thereafter ethylene gas is sparged into the
reactor to
maintain a partial pressure of 70 to 100 psi (0.5-0.7 MPa), the reactor is
then
allowed to run for about 30 nninutes. Polyethylene having a melt index of
between
15 0.01 to 10 dg/rnin is recovered.
In a preferred embodiment, the polyolefin recovered typically has a melt index
as
measured by ASTM D-1238, Condition E, at 190°C of lg/lOmin or less. In
a
preferred embodiment the polyolefin is ethylene homopolymer or copolymer. The
2o comonomer is preferably a C3 to C20 linear branched or cyclic monomer, and
in
one embodiment is a C3 to C12 linear or branched alpha-olefin, preferably
propylene, hexene, pentene, hexene, heptene, octene, nonene, decene, dodecene,
4-
methyl-pentene-1, 3-methyl pentene-1, 3,5,5-trimethyl hexene 1, and the like.
25 In a preferred embodiment the catalyst system described above is used to
make a
high density polyethylene having a density of between 0.925 and 0.965 g/cm3
(as
measured by ASTM 2839), and/or a melt index of 1.0 or less g/1 Omin or less
(as
measured by ASTM D-1238, Condition E, at 190°C). In another embodiment
the
catalyst system described above is used to make a polyethylene of 0.85 to
0.924
30 g/cm3.
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In another embodiment the polymer produced by this invention has a molecular
weight distribution (Mw/Mn) of at least 10, preferably at least 15, preferably
at
least 20, even more preferably at least 30.
Further, while not wishing to be bound by any theory, it is believed that the
polymers produced by this invention have the unique advantage of the two
polymer
products being so intimately blended that there is an even distribution of the
two
polymers across the polymer particles as they exit the reactor. The
unprocessed,
untreated granular polymer is referred to as neat polymer. The neat polymer is
then
to separated into fractions by standard sieve sizes according to ASTM D 1921
particle
size (sieve analysis) of plastic Materials, Method A or PEG Method 507.
Sieve Fraction Collected Fraction Name
size
mesh
> 2000 pm Fraction 1
18 mesh 2000- 1000 ~m Fraction 2
35 mesh <1000 - 500 wm Fraction 3
60 mesh <500-250 pm Fraction 4
120 mesh <250 -125 pm Fraction 5
<125 ~m Fraction 6
P~
The individual fractions (Fraction 1, 4, 6) are then tested for physical
properties.
Melt index is measured according to ASTM 1238, condition E, 190°C.
Crystallinity is measured using X-ray diffraction as described in example 13
below.
A unique attribute of the polymer produced herein is that the melt indices of
the
different fractions do not vary significantly. In a preferred embodiment the
melt
2o indices of Fractions l, 4 and 6 do not vary by more than 20% relative,
preferably
by not more than 15% relative, preferably by not more than 10% relative,
preferably by not more than 8% relative, preferably by not more that 6%
relative,
preferably by not more than 4% relative. Relative means relative to the mean
of
the values for Fractions 1, 4 and 6.
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Another unique attribute of the polymer produced herein is that the percent
crystallinity of the different fractions do not vary significantly. In a
preferred
embodiment the percent crystallinity of Fractions 1, 4 arid 6 do not vary by
more
than 6 % relative, preferably by not more than S% relative, preferably by not
more
than 4 % relative, preferably by not more than 3% relative, preferably by not
more
that 2 % relative. Relative means relative to the mean of the values for
Fractions 1,
4and6.
to Another unique attribute of the polymer produced herein is that the Mw/Mn
of the
different fractions do not vary significantly. In a preferred embodiment the
Mw/Mn of Fractions 1,4, 5 and 6 do not vary by more than 20% relative,
preferably by not more than 10% relative, preferably by not more than 8%
relative,
preferably by not more than 6% relative, preferably by not more that 4%
relative,
15 preferably by not more than 2% relative. Relative means relative to the
mean of
the values for Fractions 1, 4 and 6. Mn and Mw were measured by gel permeation
chromatography on a waters 150 °C GPC instrument equipped with
differential
refraction index detectors. The GPC columns were calibrated by running a
series
of narrow polystyrene standards and the molecular weights were calculated
using
2o broad polyethylene standards National Bureau of Standards 1496 for the
polymer
in question.
In another embodiment the polymer produced herein has an Mw/Mn of 8 or more,
preferably 10 or more, preferably 12 or more.
In another embodiment a parameter of polymer produced is that the crystallite
morphology varies with particle size. Fraction 1 preferably has an aspect
ratio of
0.5-1.5, fraction 4 has an aspect ratio of 1.2 to 4, Fraction 6 has an aspect
ratio of
about 1.75 to 5 provided that the fractions differ by at least 0.3. preferably
by at
least 0.5, more preferably by about 1Ø In one embodiment the aspect ratio of
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Fraction 1 <aspect ration of Fraction 4 <the aspect ratio of Fraction 6. The
aspect
ratio is [<110>/<O11>] as discussed below in example 13.
In another preferred embodiment the polymer produced according to this
invention
comprises 10-90 weight% of low molecular weight polymer (low is 50,000 or less
preferably 40,000 or less), preferably 20 to 80 weight%, more preferably 40-60
weight%, based upon the weight of the polymer.
In another embodiment the polyolefin produced is found to have at least two
1o species of molecular weights present at greater than 20 weight% based upon
the
weight of the polymer.
In another embodiment of this invention the polymer produced is bi- or multi-
modal (on the SEC graph). By bi- or mufti-modal is meant that the SEC graph of
15 the polymer has two or more positive slopes, two or more negative slopes,
and
three or more inflection points (an inflection point is that point where the
second
derivative of the curve becomes negative) OR the graph has at least has one
positive slope, one negative slope, one inflection point and a change in the
positive
and or negative slope greater than 20% of the slope before the change. In
another
20 embodiment the SEC graph has one positive slope, one negative slope, one
inflection point and an Mw/Mn of 10 or more, preferably 15 or more, more
preferably 20 or more. The SEC graph is generated by gel permeation
chromatography on a waters 150 °C GPC instrument equipped with
differential
refraction index detectors. The columns are calibrated by running a series of
25 narrow polystyrene standards and the molecular weights were calculated
using
Mark Houwink coefficients for the polymer in question.
The polyolefins then can be made into films, molded articles, sheets, pipes
and the
like. The films may be formed by any of the conventional technique known in
the
3o art including extrusion, co-extrusion, lamination, blowing and casting. The
film
may be obtained by the flat film or tubular process which may be followed by
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orientation in an uniaxial direction or in two mutually perpendicular
directions in
the plane of the film. Particularly preferred methods to form the polymers
into
films include extrusion or coextrusion on a blown or cast film line.
The films produced may further contain additives such as slip, antiblock,
antioxidants, pigments, fillers, antifog, LTV stabilizers, aritistats, polymer
processing aids, neutralizers, lubricants, surfactants, pigments, dyes and
nucleating
agents. Preferred additives include silicon dioxide, synthetic silica,
titanium
dioxide, polydimethylsiloxane, calcium carbonate, metal stearates, calcium
1o stearate, zinc stearate, talc, BaSOa, diatomaceous earth, wax, carbon
black, flame
retarding additives, low molecular weight resins, glass beads and the like.
The
additives may be present in the typically effective amounts well known in the
art,
such as 0.001 weight % to 10 weight %.
15 The films produced using the polymers of this invention have extremely good
appearance properties. The films have a low gel content and/or have good haze
and gloss. In a preferred embodiment the 1 mil film (1.0 mil =0.25p.m) has a
45°
gloss of 7 or more, preferably 8 or more as measured by ASTM D 2475. In a
preferred embodiment the 1 mil film (1.0 mil = 0.25pm) has a haze of 75 of
less,
2o preferably 70 or less as measured by ASTM D 1003, condition A.
EXAMPLES
IZ and I2, are measured by ASTM 1238, Condition E and F.
MFR Melt Flow Ratio was measured by ASTM 1238.
25 BBF (butyl branch frequency per 1000 carbon atoms) was measured by infrared
spectroscopy
described in US Patent 5,527,752.
PDI (polydispersity index) is equivalent to Mw/Mn and was measured by Size
Exclusion
Chromotography.
Mn and Mw were measured by gel permeation chromatography on a waters 150
°C
3o GPC instrument equipped with differential refraction index detectors. The
GPC
columns were calibrated by running a series of narrow polystyrene standards
and
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the molecular weights were calculated using Mark Houwink coefficients for the
polymer is question.
Melt Index (MI) was measured by the procedure according to ASTM 1238,
condition E.
Melt Index Ratio (MIR) is the ratio of I2, over Iz as measured by the
procedure
according to ASTM D 1238.
Density is measured according to ASTM D 1505.
EXAMPLE 1
1o Y-Preparation Of ~l (2 Pyridyl)N 1 Methvlethyllf 1-N-2 6-
DiisopropvlphenvllAmine
H3C~ CH3
C
N
w H'
In a dry box, 22.45 mmol (6.34 g) 2-acetylpyridine(2,6-diisopropylphenylimine)
were charged to a 250 mL round bottom flask equipped with a stir bar and
septa.
is The flask was sealed, removed from the dry box and placed under nitrogen
purge.
Dry toluene (50 mL) was added and stirred to dissolve the ligand. The vessel
was
chilled to 0° C in a wet ice bath. Trimethyl aluminum (Aldrich, 2.0 M
in toluene)
was added dropwise over ten minutes. The temperature of the reaction was not
allowed to exceed 10° C. When addition of the trimethyl aluminum was
complete,
2o the mixture was allowed to warm slowly to room temperature, and then was
then
placed in an oil bath and heated to 40° C for 25 minutes. The vessel
was removed
from the oil bath and placed in an ice bath. A dropping funnel containing 100
mL
of 5% KOH was attached to the flask. The caustic was charged to the reaction
dropwise over a 1 hour span. The mixture was transferred to a separatory
funnel.
25 The aqueous layer was removed. The solvent layer was washed with 100 mL
water then 100 mL brine. The red-brown liquid product was dried over Na2S04,
vacuum stripped and placed under high vacuum over night. 80 mL of red-brown
liquid was transferred to a 200 mL Schlenk flask equipped with a stir bar. A
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distillation head with a dry ice condenser was attached to the flask. The
mixture
was vacuum distilled yielding approximately 70 g of dark yellow viscous liquid
product.
EXAMPLE 2
Preparation Of f 1 (2 PvridvllN 1-Meth l~ethyllf 1-N-2 6-Diisonronvlphen 1
Amido~ Zirconium Tribenzvl
H3C' CH3 CH3
C ~H3C'~,.,,
/H3C
N N
Z/f
CHz ~ ~ ' 'CH CH3
z
C z v
1o In a darkened room and darkened dry box, 5.0 mmol (1.45 g) of the ligand
made in
Example 1 were charged to a 100 mL Schlenk tube equipped with a stir bar. The
ligand was dissolved in 5 mL of toluene. To a second vessel equipped with a
stir
bar was charged 5.5 mmol (2.Sg) tetrabenzyl zirconium and 10 mL toluene.
The ligand solution was transferred into the tetrabenzyl zirconium solution.
15 The vessel was covered with foil and allowed to stir at room temperature in
the dry
box. After 6 hours at room temperature 80 mL dry hexane was added to the
reaction solution and allowed to stir overnight. The reaction mixture was
filtered
through a medium porosity frit with approximately 2g pale yellow solids
collected.
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EXAMPLE 3
Pr~aration Of ff 1 f2 Pvridvl)N 1 Methyleth~]-f 1-N-2 6-Diisonronyl>7henvl
A_midoj,]f2 Methvl-1-Phenxl-2-Propoxvl Zirconium Dibenzvl
H3C\ CH3 CH3
isC'./.,,.-
H3C-.
~cHz
s
To an oven-dried, cooled, purged and sealed GC vial was charged 0.10 mL dried
acetone. The GC vial was sealed in a shell vial and taken into the dry box. In
a
darkened room and darkened dry box 2.0 mmol (1.3g) of the material made in
1o Example 2 and 9 mL toluene were charged to 1 100 mL Schlenk flask equipped
with a stir bar. To a second GC vial was charged 2.0 mmol (146 uL) acetone and
1.0 mL toluene. The acetone/toluene solution was transferred dropwise via
syringe
into the stirred solution of [1-(2-pyridyl) N-1-methylethyl][1-N-2,6-
diisopropylphenylamido] zirconoum tribenzyl. The vessel was covered with foil
i5 and allowed to stir at room temperature in the dry box overnight. The
reaction
solution was vacuum stripped to a tacky orange residue. Dry hexane (20 mL) was
added and the residue stirred vigorously, then vacuum stripped again to a
yellow-
orange glass. Hexane was added again and vigorously stirred. The vessel was
placed in a freezer (-24° C) for approximately 2 hours. The mixture was
filtered
2o through a medium porosity frit. Pale yellow solids (0.8 g) were collected.
Slow
deliberate feeding of the acetone with good mixing appears best.
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EXAMPLE 4
A series of bimodal ethylene/hexene copolymers were made in a laboratory
scale,
slurry phase reactor using mixed catalyst compositions of the complexes
prepared
in Example 2 and Example 3 according to the invention with modified methyl
alumoxane (MMAO) cocatalyst type 3A (commercially available from Akzo
Chemicals, Inc. under the trade name Modified Methylalumoxane type 3A,
covered under patent number US 5,041,584).
In each case, the catalyst composition was prepared by preparing mixtures of
the
to complexes from Example 2 and Example 3 in toluene, and then contacting with
MMAO solution (7.0 wt % A1 in heptane) in the presence of 0.1 mL 1-hexene.
Polymerization reaction conditions were 85° C, 85 psi (586 kPa)
ethylene, 43 mL
of 1-hexene, 0.5 micromole Zr, and a MMAO/Zr mole ratio of 1,000:1. Complex
ratios are expressed as the mole ratios of the complex prepared in Example 3
to the
complex prepared in Example 2. Results are shown in Table 1 below.
Table 1
Complex Activity Iz MFR BBF PDI
Ratio gPE/mmolcat/
100~si C2/hr dg_/min ner 1000 C's
100:0 139765 162.2 1.82 6.28 11.18
90:10 291765 13.49 61.66 10.08 25.84
80:20 175529 0.05 1,027 7.54 23.74
60:40 235765 0.0085 317.4 9.92 28.24
50:50 189647 0.012 173.1 11.01 30.25
Size Exclusion Chromatography was conducted on the resins prepared in Table 1.
The
results clearly demonstrate an increase in the high molecular weight component
with
increasing concentrations of the complex from Example 2. The relative amounts
of the
3o complexes from Example 3 and Example 2 respectively reflect the low and
high molecular
weight components in these bimodal resins. This shows that the two catalysts
are highly
compatible.
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EXAMPLE 5
An ethylene hexene copolymer was produced in a 14 inch (35.6cm) pilot plant
gas phase
reactor operating at 85 °C, 220 psi ( 1517 kPa) having a water cooled
heat exchanger. The
ethylene was fed in at a rate of about 55 pounds of ethylene per hour
(25kg/hr) and hexene
was fed in at 1.4 pounds per hour(0.64 kg/hr) and hydrogen was fed in at rate
of 0.021
pounds per hour (0.01 kg/hr) to make about 35 pounds per hour (15.9 kg/hr) of
polymer.
Total reactor pressure was 350 psi (2413 kPa). The nitrogen was present at
about 3-7
pounds/hour (1.4 kg-3.2 kg). The reactor was equipped with a plenum set at
1800 pounds
1o per hour (818.2 kg/hr) with a single hole tapered nozzel injector having a
0.055 inch (0.14
cm) inside diameter. (The plenum is a device used to create a particle lean
zone in a
fluidized bed gas phase reactor. For more information on plenum usage see US
Patent
5,693,727) This procedure was repeated and one or more of the reaction
temperature, the
Al/Zr ratio, the reaction temperature, the injection temperature or the
hydrocarbon feed
Garner were varied as reported in Table 2.
Table 2
Exam Rxn tem Wt% low Mw Catalyst Mw/Mn AI:Zr ratio
le ~
A 85 60 3 14 350:1::Al:Zr
B 90 57 3 16 360:1::AL:Zr
C 95 51 3 12 350:1::Al:Zr
D 105 35 3 11 350:1::Al:Zr
E 85 22 60/40 2:3 450:1::Al:Zr
F 85 70 3 72:1::A1:
Zr
"Wt% low Mw" is the weight % of the lower molecular weight species produced as
characterized by Size Exclusion Chromatography using a log normal Gaussian
2o deconvolution.
EXAMPLE 6
The example above was repeated with the catalysts produced in examples 2 and 3
except
that the polymerization conditions were 85 °C, 220 psi ( 1517 kPa)C2,
500:1 Al/Zr,
catalyst feed 10 cc/hr, MMAO feed 300 cc/hr (2.3 wt% AI in hexane). The ratio
of the two
catalysts was varied.
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Table 3
Catalyst ratio Activity IZ MFR density
2/3 f~ PE/mmolZr/hr~dg/min ~/cm3-
60/40 15,651 0.196 51.47 0.9455
40160 17,929 0.150 59.89 0.9475
20/80 16,905 0.165 63.45 0.9498
0/100 16,061 0.167 76.27 0.951
80/20 40,048 0.150 52.08 0.9422
is
EXAMPLE 7
Two ethylene hexene copolymers were produced in an 8 foot (2.4 m) diameter gas
phase
reactor (having a volume of about 2000 cubic feet) having a bed height of 38
feet(/ 1.6 m).
The ethylene feed rate was about 8000 to 9000 pounds per hour (3636-4090
kglhr). The
hexene feed rate was about 200-230 pounds per hour (90.0-104.5 kg/hr). The
hydrogen
feed rate was about 1-2 pounds per hour (2.2 to 4.4 kg/hr). The copolymer was
produced
at 8000-9000 pounds per hour(3636-4090 kg/hr). 30-60 pounds per hour of
nitrogen
(13.6-27.3 kg/hr) were fed into the reactor. The reactor was equipped with a
plenum set at
50,000 pounds per hour (22,727 kg/hr) and three hole nozzel having a diameter
of 0.125
inches (0.32cm) tapering to a diameter of 0.05 inches (0.13cm) at the central
hole and two
other holes 0.30 inches ( 0.76 cm)from the nozzel end perpendicular to the
flow of the gas
and 5/64ths of an inch (0.20cm)wide. The cycle gas velocity was about 2 -2.2
feet per sec
(60-67 cm/sec). The injection temperature was 22 °C for the first run
and 80 ° C for the
second run. The catalyst was the catalyst produced in example 3 combined with
2 weight
modified methyl alumoxane 3A in an AI:Zr ratio of 150:1. The first run
produced an
ethylene hexene copolymer having 44 weight% lower molecular weight portion and
the
second run produced 36 weight% of lower molecular weight portion.
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EXAMPLE 8
Five 0.02 Molar solutions in toluene of the compounds prepared in examples 2
and 3 were
prepared in ratios of 80/20, 60/40, 40/60, 20/80 and 0/100. They were
polymerized
according to the procedure in example 5 using modified methyl alumoxane 3A as
the
cocatalyst. The bed temperature was maintained at 85 °C. The ethylene
partial pressure
was 220 psi (1537kPa) and the AI:Zr ratio was 500:1.
Table 4
80/20 0/40 0/60 0/80 /100
6/C2Ratio 8.1-9.1 6.6-7.7 6.1-6.7 5.4-5.6 5.4-5.7
X 10 3
2/C2 Ratio 3.7 - 25.517.5 - 14.0 12.3 - 12.612.1 -
18.6 12.2
x 10-3
reduction 8 6 6 6 7
ate h
ctivity 19000 17500 15000 16100 17500
PE/mmolZr
elt Index .15-0.26 .17-0.26 .13-0.34 0.12-0.17 .16-0.21
min
low Index 8.07-12.3 .95-12.88 8.81-14.07.68-10.95 12.53-14.50
/min
elt Flow 9.87-55.636.37-64.3932.96-65.7561.24-81.8770.73-77.83
Rati
FR
ensit cc .942-0.944.0945-0.947.947-0.950.950-0.951 .9951-0.952
EXAMPLE 9
SYNTHESIS OF [~2-PYRIDYL),-N-1-METHYLETHYLl(1-N-
2 6DIISOPROPYLPHENYLAMID01[3-BENZYL-3-PENTOXYLZIRCONIUM
DIBENZYL
Diethyl ketone (40 mmol, 4.0 mL, Aldrich, 3-Pentanone, 99.5%, [86.13] ) was
2o dissolved in 96 mL of dry toluene. The diethyl ketone solution was slowly
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transferred into a stirring solution (400 mL, 0.125M in toluene) of the
complex
prepared in Example 2. The resulting solution was allowed to stir over night.
EXAMPLE 10
SYNTHESIS OF f 1 ~2-PYRIDYL)-N-1-METHYLETHYLl[1-N-2,6
DIISOPROPYLPHENYLAMIDO][2-BENZYL-2-BUTOXY] ZIRCONIUM
DIBENZYL
to Methyl ethyl ketone (40 mmol, 3.6 mL, Aldrich, 2-Butanone, 99.5%,) was
dissolved in 100 mL of dry toluene. The methyl ethyl ketone solution was
slowly
transferred into a stirring solution (400 mL, 0.125M in toluene). of the
complex
prepared in Example 2. The resulting solution was allowed to stir over night.
EXAMPLE 11
In a dry box, 1-hexene (0.1 mLs, alumina dried) was charged to an oven dried,
4
dram glass vial. The complex from Example 2 (0.25 micromoles, 2.0 microliters
,
a 0.125M solution in toluene), and the complex prepared in Example 9 (0.25
moles, 3.7 microliters, a 0.067M solution in deuterated benzene) was added to
the
1-hexene resulting in a pale yellow solution. MMAO type 3A (0.25 mmoles) was
then added to the vial resulting in a pale yellow reaction solution. The
reaction
solution was charged to the reactor containing 600 mLs n-hexane, 43 mLs 1-
hexene, and 0.13 mLs (0.25 mmoles) MMAO type 3A, and run at 70°C, 85
psi
2s ethylene, and 10 psi hydrogen for 30 minutes. The reaction produced 26.3g
of
polyethylene resin (activity = 123765 g polyethylene/ mmole Zr/ hour/ 100psi
ethylene, I2 = 28.49, I21 = 838, MFR = 29.4, BBF = 7.63). Size Exclusion
Chromatography (SEC) revealed the following molecular weight Results: Mn =
12611, Mw = 50585, PDI = 4.01. The SEC graph is presented as Figure 6.
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EXAMPLE 12
In a dry box, 1-hexene (0.1 mLs, alumina dried) was charged to an oven dried,
4
dram glass vial. The complex from Example 2 (0.25 pmoles, , a 0.125M solution
in
toluene), and the complex from Example 10 (0.25 pmoles, , an 0.080M solution
in
toluene) was added to the 1-hexene resulting in a yellow solution. MMAO type
3A
(0.25 mmoles) was then added to the vial resulting in yellow reaction
solution. The
reaction solution was charged to a 1L slurry reactor containing 600 mLs n-
hexane,
43 mLs 1-hexene, and 0.13 mLs (0.25 mmoles) MMAO type 3A, and run at
70°C,
85 psi ethylene, and 10 psi hydrogen for 30 minutes The reaction produced
30.7g
of resin (activity = 144471 g polyethylene/ mmole Zr/ hour/ 100psi ethylene,
I2 =
11.47, I21 = 468, MFR = 40.8, BBF 7.53).: Size Exclusion Chromatography (SEC)
revealed the following molecular weight Results: Mn = 12794, Mw = 62404, PDI
= 4.88. The SEC graph is presented as figure 7.
EXAMPLE 13
An ethylene hexene copolymer (A) having a density of about 0.946 g/cc was
produced
according to the procedure in example 5 except that the catalyst from example
3 was added
at a rate of 9cc/hour and the catalyst from example 2 was fed at a rate of
lcc/hour (90:10
ratio). Hexene was fed at about 0.8-0.9 lbs (0.36-0.41 kg) per hour. Ethylene
was fed at a
rate of about 41 to 43 pounds (18.5-19.4kg) per hour. Hydrogen was fed at a
rate of about
17-20 miliipounds (7.7-9.1g) per hour and the hexane Garner was fed at a rate
of about 100
cc/hour. The ethylene partial pressure was 120 psi (827 kPa) and the reactor
temperature
was 75°C The aluminum zirconium ratio was AI:Zr::300: 1.
Another ethylene hexene copolymer (B) was produced using the same procedure
except
that only the catalyst from example 3 was fed into the reactor (10 cc/br), the
reactor
temperature was 95°C, hydrogen was fed at a rate of 12-14 millipounds
(5.4-6.4g)per hour,
3o the ethylene feed was fed at 41 to 45 pounds (18.5-20.3kg)per hour and the
ethylene partial
pressure was 220 psi(827kPa). The copolymer had a density of 0.951 g/cc.
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Another ethylene hexene copolymer (C) was produced using the same procedure
except
that only the catalyst from example 3 was fed into the reactor (12 cc/hr), the
reactor
temperature was 95 °C, hydrogen was fed at a rate of 12-13 millipounds
(5.4-5.9g)per
hour, the ethylene feed was fed at 44 to 47 pounds ( 19.9-21.2kg)per hour, the
ethylene
partial pressure was 220 psi(827kPa), and the hexane carrier was fed in at a
rate of 70/cchr.
The copolymer had a density of 0.951 g/cc.
These copolymers were then fractionated using the following sieves:
Sieve Fraction CollectedFraction Name
size
mesh > 2000 p,m Fraction 1
18 mesh 2000-1000 p,m Fraction 2
35 mesh <1000 - 500 p,m Fraction 3
60 mesh <500 - 250 pm Fraction 4
120 mesh <250-125 pm Fraction 5
pan <125 p,m Fraction 6
The fractions were then characterized as reported in tables A, B, C and D.
Summary of the Experimental Procedure used for X-ray diffraction Data
collection and Techniques used for Percent Crystallinity and Crystallite
t5 Morphology Analysis.
X-ray Diffraction Data Collection:
A Siemens GADDS X-ray diffraction (XRD) unit equipped with a Copper X-ray
2o tube source (~, = 1.54056 l~) running at a power setting of 40 kV and 40
mA, a graphite
monochrameter, a 0.3 mm collimator prior to the sample and a multi-wire
General Area
Diffraction Detector (GADD) with a sample-detector distance of 15 cm was the
condition
used for all data collection. Large individual particles were glued to a thin
glass rod which
allowed the particle to be suspended and rotated in the beam without any
contribution from
25 the glass rod or glue. Fine particles were placed in a thin silica
capillary for the analysis.
All data collection was done in transmission mode with a beam stop 3 cm behind
the
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sample. Spectra were collected at three different diffractometer settings with
the detector
covering the following 28 regions, 4°-34°, 32°-58°
and 56°-76°, with collection times
typically of 600 s per region. These three different regions were unwarped
(distortion
correction) and then spliced together to form a single spectra covering
4°-76° 28. The
GADDS system at the 15 cm sample-detector distance provided a view of
120° arc of the
Debye ring. This clearly showed a uniform intensity along the ring which is
indicative of a
perfectly random homogeneous structure showing no presence of preferred
orientation or
texturing.
Curve Fitting:
The full profile curve fitting program supplied with the GADDS system was used
for peak
profile fitting to the spectra.. For large particles an air scatter pattern
collected under the same
conditions was subtracted from the experimental data prior to fitting, in the
case of small
particles a spectra combining the blank silica capillary and air scatter was
subtracted from
the experimental data prior to fitting. Four components were used to fit the
diffraction
data; {i) diffraction peaks were fitted with a pseudo-voigt profile-shape-
function with a
mixing parameter of 1, (ii) amorphous peaks were fitted with a Lorentzian
profile-shape-
function with the FWHM (full width half maximum) of the peak and peak
positions being
fixed based upon amorphous scattering simulations, (iii) a paracrystalline
component was
fitted with a Pearson VII profile-shape-function with an exponent of 50 and
(iv) a linear fit
for the compton scattering.
Once the Compton scattering was subtracted from the data, the total
diffracted intensity in the pattern was fit with three components, ( 1 )
amorphous
intensity Iam, (2) paracrystalline component Ipa~ and (3) crystalline
diffraction peaks
IXai. The following expression was then used to calculate the percent
crystallinity:
Percent Crystallinity = Ixa~/(Iam + Ipar~ + Ixai x 100
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Crystaillite Size:
The crystallite size was measured using the peak-width at half maximum
intensity
of the {110} and {011 } reflections in X-ray diffraction patterns from
granular
polyethylene resin. These two values allow the size of the crystallite in the
given
crystallographic direction to be calculated using the Schemer equation:
Crystallite Size (t} = 0.9~,/B'cos6$
B' = Bmeasured - Binstrumental broadening
1o Where ~, is the wavelength of the incident X-ray, B' is the corrected peak
width in
radians at half maximum intensity (the instrumental beam broadening component
was measured using a National Bureau of Standards SRM 660 Lanthanum
Hexaboride sample), 8B is the peak position and t is the size of the crystal
in the
crystallographic direction based upon the reflection of interest. The <110>
15 reflection provides crystallite size information in the <110> direction
that lies in
the ab plane of the PE orthorhombic crystal, similarly the {011 } reflection
provides
crystallite size data in the <Ol l> direction which lies in the be plane which
has a c-
axis component, and therefore, information on the crystallite thickness can be
obtained.
Therefore, the magnitude of the crystallite size in these two directions can
provide
information on the crystallite morphology through a shape factor defined as
<110>/<O11>. When the ratio is large, the crystals are large in the ab plane
but
thin in the be plane, hence they are "plate like," as the ratio approaches
unity, both
dimensions are similar and hence the crystallite morphology is more cuboidal
or
spherical in shape.
Table A provides X-ray diffraction data on all three samples studied. The
degree of
crystallinity was found not to change as a function of particle size, with the
small
particles having the same percent crystallinity as the much larger particles.
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The crystallite size in the ab plane was observed to decrease monotonically as
particle size increased in both samples. Conversely, the crystallite size in
the be
plane (estimate of the c-axis component) was observed to increase
monotonically
as a function of particle size.
These results suggest that the crystallite shape is changing as a function of
particle
size. The crystallite shape in the small particles is more "plate-like" with
the aspect
ratio [<110>/<O11 >J - 2.2-3.5, as the particle grows the 'aspect ratio moves
towards - 1-1.5 suggesting a crystallite more cuboidal/spherical in shape.
Thus the
shape of the crystallite domains embedded in the granular resin changes from
"plate-like" to cuboidal/spherical as the particles grow in size from PAN
(<125
Vim) to 10 mesh (>2000 pm). The particles could be viewed as having a graded
type
microstructure.
The observed behavior in this catalyst system is just one example of a graded
microstructure. The opposite structure could form with cuboidal/spherical
crystallites at the center which then transition over to a more "plate-like"
morphology. An alternative crystallite morphology may be "rod-like" in which
the
shape factor becomes < 1. The distribution of different crystallite
morphologies
2o could lead to a wide range of possible graded microstructures that could be
controlled by the type of catalyst.
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Table A - X-ray Diffraction Data From Exam_,ple 13 Samples
Sample %Xal % % Am FWHM FWHM Xal SizeXal
Para 110 011 110 Size
011
A
10-mesh-1 55.8 4.3 39.9 0.4086 0.5883 197.7 143.4
10-mesh-2 56.2 4.7 39.1 0.3926 0.5883 205.8 143.4
10-mesh-3 56.1 5.3 38.6 0.4091 0.5883 197.5 143.4
60-mesh-1 55.6 6.5 37.8 0.3557 0.6647 227.2 126.9
PAN-1 53.7 3.9 42.4 0.3510 0.8433 230.2 100.0
PAN-2 55.1 5.6 39.4 0.3450 0.7190 234.2 117.3
Av. 10 mesh56.0 4.8 39.2 0.40347 0.5883 200.4 143.4
Stdev 10 0.2 0.50 0.6 0.0094 0.0000 4.7 0.0
Av. 60/Pan 54.8 5.3 39.9 0.3506 0.7423 230.5 114.7
Stdev 60/ 1.0 1.3 2.3 0.0054 0.0916 3.5 13.6
an
C
10-mesh-1 61.9 4.1 34.0 0.3028 0.4678 266.9 180.3
10-mesh-2 60.8 3.1 36.1 0.2975 0.4678 271.6 180.3
10-mesh-3 60.0 3.3 36.7 0.2970 0.4695 272.1 179.6
60-mesh-1 61.5 5.3 33.2 0.2672 0.5274 302.4 159.9
PAN-1 59.3 3.8 36.9 0.2393 0.5477 337.7 154.0
PAN-2 59.9 6.9 33.2 0.2517 0.5875 321.0 143.6
Av. 10 mesh60.92 3.5 35.6 0.2991 0.4684 270.2 180.1
Stdev 10 1.0 0.5 1.4 0.0032 0.0010 2.9 0.4
Av. 60/Pan 60.2 5.3 34.4 0.2527 0.5542 320.4 152.5
Stdev 60/ 1.1 1.5 2.1 0.0140 0.0306 17.6 8.3
an
B
10-mesh-1 63.4 7.9 28.6 0.2931 0.3638 275.9 229.2
10-mesh-2 65.2 6.8 28.0 0.2278 0.3638 355.0 229.2
10-mesh-3 63.6 6.8 29.7 0.2518 0.5895 321.2 143.3
60-mesh-1 62.7 6.1 31.2 0.1800 0.6451 449.3 131.0
PAN-1 64.7 6.7 28.6 0.1768 0.6451 457.4 131.0
PAN-2 65.9 6.9 28.2 0.1754 0.6451 461.1 131.0
Av. 10 mesh64.1 7.2 28.8 0.2576 0.4422 317.4 200.6
Stdev 10 1.00 0.7 0.8 0.0330 0.1275 39.7 49.6
Av. 60/Pan 64.1 6.6 29.3 0.1774 0.6451 455.9 131.0
Stdev 60/ 1.2 0.4 1.6 0.0024 0.0000 6.0 0.0
an
For Tables B, C and D CHMS is the high molecular weight species (over 500,000)
CLMS is the low molecular weight species (less than 3000), VLD is very low
density, LD is low density, HD is high Density, CCLDI is crystallizable chain
length distribution index and is defined in US patent 5,698,427. CDI (50) is
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composition distribution index that measures how much polymer is within 25 %
of
either side of the median. CDI (100) is composition distribution index that
measures how much polymer is within 50% of either side of the median. Both
composition distributions are measured using the Temperature Rising Elution
Fractionation (TREF) technique as described in Wild et al (J. Polym. Sci.
Phys. Ed.
Vol 20, p441-445 (1982)). A dilute solution of the polymer in a solvent such
as
1,2,4-trichlorobenzene is loaded into a packed column at high temperature. The
column is allowed to cool slowly at 0.1 °C/min to ambient temperature.
During the
slow cooling process, the ethylene polymer is crystallized onto the packing in
the
order of increasing branching (decreasing crystallinity) with decreasing
temperature. Once cooled, the column is reheated at 0.7 °C/min, with a
constant
so 1 vent flow through the column and the effluent is monitored with an
infrared
concentration detector.
The CDI(100) and CDI(50) indices are similar to the "Composition Distribution
Breadth Index" (CDBI). CDBI is defined as the weigh percent of the copolymer
chains having a comonomer content within 50% (~ 25%) of the median total molar
comonomer content (see US patent 5,470,811). The difference between the CDBI
and the CDI(50) index is that the CDI(50) utilizes the mean branching
frequency
(or comonomer content) instead of the median comonomer content. The CDI(50)
is determined from the TREF data by converting the elution temperature to
branching frequency as follows:
Branching frequency can be expressed as the average distance (in CHz units)
between branches along the main polymer chain backbone or as the
crystallizable
chain length (L) where,
t,=100 and limL ->2260
BF BF-'°
Utilizing moments of distribution analogous to the molecular weight
distribution, one
can define a number average (L") and weight average (LW~ moments for L; where:
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L" =1/E;(w;/L;) and LW = E;w;L;
w; is the weight fraction of the polymer component i having an average
backbone
chain spacing L; between two adjacent branch points. The composition
distribution
index or crystallizable chain length distribution index (CCLDI) is then
defined as:
CCLDI = LW/L"
The mean branching frequency is calculated by: BF = EW;b;
where W; and b; are the weight fraction and branch frequency respectively at
each
slice i of the TREF chromatogram. CDI(50) is then calculated by determining
the
accumulative weight fraction contained within t25% of BF. CDI(100) is defined
as the accumulative weight fraction contained within ~SO% of BF.
Table B characterization Data for Polymer A
Fraction 1 4 5 6
Mn 10,604 8,320 8,815 8,831
Mw 230,395 227,935 234,524 247,901
Mw/Mn 19.2 27.4 26.6 28.1
CHMS % 11.3 13.1 13.7 14.5
CLMS % 1.3 2.2 2.0 2.0
VLD % 3.5 5.7 3.6 7
LD % 5.8 7.6 4.9 8.8
HD % 66.1 62 67.7 64.1
CCLDI 10.9 12.4 10.6 13.9
CDI50% 9.8 10.2 8.7 10
CDL( 100)(%)19.5 ~ 20.2 17.1 19.7
~
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Table C Characterization Data for Pol m~er B
Fraction 1 3 4 S 6
Mn 12,335 11486 10,957 10,408 10,400
Mw 285,402 236,008 249,496 244,990 248,000
Mw/Mn 23.1 22.9 22.8 23.5 238.
CHMS % 17.1 15.9 15.3 15.0 15.2
CLMS % 0.5 0.6 0.7 0.7 0.73
VLD % 4.2 5.9 2.5 3.8 2.3
LD % 5.7 7.6 3.8 5.5 3.8
HD % 65.5 60.9 63.8 58 62.6
CCLDI 11 11.7 9.7 10.5 9.7
CDI 50 % 11 13.9 12.5 15.5 14.1
CDL 100 20.6 26.5 23.5 28.8 25.3
%
Table D Characterization Date for Po~mer C
Fraction 1 ~ 4 5 6
Mn 13,114 13,081 11,451 _11,328
Mw 243,241 236,908 219,370 217,120
Mw/Mn 18.5 18.2 19.2 19.2
CHMS % 13.7 13.6 12.6 12.5
CLMS % 0.7 0.6 0.9 1.0
VLD % 1.5 2.5 1.8 3.9
LD % 1.9 3.3 2.9 4.5
HD % 84.3 77 78.6 75.4
CCLDI 6.6 8.4 8.1 9.2
CDI50 % 4.1 9.2 8.3 11.8
CDL 100 % 9.3 17.7 16.11 21.5
EXAMPLE 14
A bimodal ethylene/hexene copolymer was made in a laboratory scale slurry
phase
1o reactor using the complex prepared in Example 3 according to the invention
with
MMAO type 3A co-catalyst (commercially available from Akzo Chemicals, Inc.
under the trade name Modified Methylalumoxane type 3A, covered under patent
number US 5,041,584). In this experiment MMA03A was allowed to react 4
hours in toluene with the complex prepared in Example 3 prior to conducting
the
polymerization reaction.
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In a dry box, toluene (0.4mLs, alumina dried) was charged to an oven dried, 4
dram glass vial. ANd the complex prepared in Example 3(2.0 micromoles,
0.067mL of an 0.030M solution in deuterated benzene) was added to the toluene
resulting in a pale yellow solution. MMAO type 3A (1.0 mmoles, 0.52 mL, 1.89M,
7.0 wt% in heptane solvent) was then added to the vial resulting in an
0.002026M
pale yellow reaction solution. The vial was then encased in aluminum foil.
After
4.0 hours, 0.25mLs (0.5 p.moles ZR, 0.25 mmoles MMAO) of the reaction solution
was charged to the reactor containing 600 mLs n-hexane, 43 mLs 1-hexene, and
l0 0.13 mLs (0.25 mmoles, 1.89M, 7.0 wt% in heptane solvent) MMAO type 3A.
The reactorwas run at 85degrees C and at 85 psi (0.6MPa) ethylene for 30
minutes.
The reaction produced 44.38 of polyethylene resin (activity =
208471gpolyethylene/mmoleZr/hour/100psi ethylene (to convert psi to
megapascals multiply the psi valuse by 0.0068948.}, IZ =20.9, I21 = 824.1, BBF
=
is 9.5 butyl branches/1000CH2. Size Exclusion Chromatography (SEC) revealed
the
following molecular weight properties: Mn = 9123, Mw = 104,852, Mw/Mn 11.49.
The SEC graph is presented as figure 8.
EXAMPLE 15
25
In a dry box" MMAO type 3A (5.8 mLs, 10 mmoles, 1.74M, 6.42 wt% in heptane)
was charged to an oven dried, 4 dram glass vial. 2-methyl-1-phenyl-2-
propanol(15.5 ,uLs, 0.1 mmoles) was added to the MMAO dropwise while stirring
resulting in a clear solution.
In a dry box, toluene (0.1 mLs, alumina dried) was charged to an oven dried, 4
dram glass vial. The complex prepared in Example 2 (0.5 pmoles, 6.3
microliters
of an 0.080M solution in toluene) was added to the 1-hexene resulting in a
pale
yellow solution. The MMAO/ 2-methyl-1-phenyl-2-propanol solution prepared in
3o the paragraph above (0.25 mmoles, 0.13 mL) was then added to the vial
resulting in
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pale yellow reaction solution. The vial was heated in an oil bath at
50°C for 5
minutes resulting in a reddish brown reaction solution.
The reaction solution was charged to a 1-L slurry reactor containing 600 mLs n-
hexane, 43 mLs 1-hexene, and 0.13 mLs (0.25 mmoles) MMAO/ 2-methyl-1-
phenyl-2-propanol solution, and run at 85°C and 85 psi (0.6 MPa)
ethylene for 30
minutes. The reaction produced 16.3g of polyethylene resin (activity = 76706g
polyethylenel/ mmole Zr/ hour/ 100 psi (0.7MPa) ethylene, IZ = 0.069, I2, =
2.15,
MFR = 31.1, BBF = 7.71). Size Exclusion Chromatography (SEC) revealed the
l0 following molecular weight properties: Mn = 54,637, Mw= 292,411, PDI=5.35.
EXAMPLE 16
In a dry box, MMAO type 3A (5.8 mLs, 10 mmoles, 1.74M, 6.42 wt% in heptane)
was charged to an oven dried, 4 dram glass vial. 2-methyl-1-phenyl-2-propanol
(15.5 ~Ls, 0.1 mmoles) was added to the MMAO dropwise while stirnng resulting
in a clear solution.
In a dry box, toluene (0.1 mLs, alumina dried) was charged to an oven dried, 4
dram
2o glass vial. The complex prepared in Example 2 (0.5 moles, 6.3 microliters
of an
0.080M solution in toluene) was added to the toluene resulting in a pale
yellow
solution. The MMAO/ 2-methyl-1-phenyl-2-propanol solution prepared in the
paragraph above (0.25 mmoles, 0.13 mL) was then added to the vial resulting in
pale
yellow reaction solution. The vial was heated in an oil bath at SO°C
for 15 minutes
resulting in a reddish brown reaction solution.
The reaction solution was charged to a 1-L slurry reactor containing 600 mLs n-
hexane, 43 mLs 1-hexene, and 0.13 mLs (0.25 mmoles) MMAO/ 2-methyl-1-
phenyl-2-propanol solution, and run at 85°C and 85 psi (0.6MPa)
ethylene for 30
3o minutes. The reaction produced 13.2g of polyethylene resin (activity =
62118g
polyethylene/ mmole Zr/ hour/ 100psi (0.7MPa) ethylene, IZ = 0.248, Iz~ =
7.85,
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MFR = 31.6, BBF = 6.30). Size Exclusion Chromatography (SEC) revealed the
following molecular weight properties: Mn = 42,411, Mw = 205,990, PDI = 4.86.
All documents described herein are incorporated by reference herein, including
any
priority documents and/or testing procedures. As is apparent form the
foregoing
general description and the specific embodiments, while forms of the invention
have been illustrated and described, various modifications can be made without
departing from the spirit and scope of the invention. Accordingly it is not
intended
that the invention be limited thereby.
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