U.S. patent application number 11/006436 was filed with the patent office on 2006-06-08 for dual catalyst on a single support.
This patent application is currently assigned to NOVA Chemicals (International) S.A.. Invention is credited to Cliff Robert Baar, Gail Baxter, Peter Phung Minh Hoang, Peter Zoricak.
Application Number | 20060122054 11/006436 |
Document ID | / |
Family ID | 35929702 |
Filed Date | 2006-06-08 |
United States Patent
Application |
20060122054 |
Kind Code |
A1 |
Hoang; Peter Phung Minh ; et
al. |
June 8, 2006 |
DUAL CATALYST ON A SINGLE SUPPORT
Abstract
Bimodal polyolefins having a reverse or partial reversed
comonomer incorporation may be prepared in the presence of a dual
catalyst on the same support wherein each catalyst has a different
response to temperature, ethylene partial pressures, partial
pressure of non-polymerizable hydrocarbons present in the reaction
mixture and hydrogen partial pressure.
Inventors: |
Hoang; Peter Phung Minh;
(Calgary, CA) ; Baar; Cliff Robert; (Calgary,
CA) ; Zoricak; Peter; (Calgary, CA) ; Baxter;
Gail; (Calgary, CA) |
Correspondence
Address: |
KENNETH H. JOHNSON
P.O. BOX 630708
HOUSTON
TX
77263
US
|
Assignee: |
NOVA Chemicals (International)
S.A.
|
Family ID: |
35929702 |
Appl. No.: |
11/006436 |
Filed: |
December 7, 2004 |
Current U.S.
Class: |
502/103 ;
502/129; 526/118; 526/119; 526/172 |
Current CPC
Class: |
C08F 10/00 20130101;
C08F 210/16 20130101; C08F 210/16 20130101; C07F 17/00 20130101;
C08F 210/16 20130101; C07F 7/003 20130101; C08F 4/65912 20130101;
C08F 4/65904 20130101; C08F 2500/05 20130101; C08F 4/64048
20130101; C08F 210/14 20130101; C08F 10/00 20130101; C08F 2410/04
20130101; C08F 4/6592 20130101; C08F 4/65916 20130101 |
Class at
Publication: |
502/103 ;
502/129; 526/118; 526/119; 526/172 |
International
Class: |
C08F 4/02 20060101
C08F004/02 |
Claims
1. A dual catalyst system suitable for producing a bimodal resin
having at least one higher molecular weight fraction having a
greater comonomer incorporation than that of a lower molecular
weight fraction wherein: (i) the first component of which comprises
the formula: ##STR7## wherein M is a group IV transition metal;
R.sup.1 and R.sup.6 are independently selected from the group
consisting of a hydrogen atom, alkyl radicals having up to 15,
carbon atoms, aryl radicals having up to 25, carbon atoms, alkoxy
radicals having up to 15 carbon atoms, and amido radicals which are
unsubstituted or substituted by up to two alkyl radicals containing
up to 15 carbon atoms, R.sup.2 and R.sup.7 are independently
selected from the group consisting of alkyl radicals having up to
15 carbon atoms, aryl radicals having up to 25 carbon atoms and
silyl radicals of the formula Si(R.sup.11).sub.3 wherein each
R.sup.11 is independently selected from the group consisting of
alkyl radicals having up to 15, carbon atoms, and aryl radicals
having up to 25 carbon atoms; R.sup.3, R.sup.4, R.sup.5, R.sup.8,
R.sup.9 and R.sup.10 are independently selected from the group
consisting of a hydrogen atom, a heteroatom containing group having
up to 20 carbon atoms, and a hydrocarbon group containing up to 25
carbon atoms, provided that none of these groups has a Hammett
.sigma..sub..rho. value greater than 0.20; X and X' are selected
from the group consisting of a halogen atom, alkyl radicals having
up to 15 carbon atoms, aryl radicals having up to 25 carbon atoms,
alkoxy radicals having up to 15 carbon atoms, amido radicals which
are unsubstituted or substituted by up to two alkyl radicals
containing up to 15 carbon atoms, and phenoxy radicals having up to
18 carbon atoms; (ii) the second component of which comprises a the
formula: ##STR8## wherein M is a group 4 metal; Pl is a
phosphinimine ligand; L is a monoanionic ligand selected from the
group consisting of a cyclopentadienyl-type ligand or a bulky
heteroatom ligand; Y is an activatable ligand; m is 1 or 2; n is 0
or 1; and p is an integer and the sum of m+n+p equals the valence
state of M.
2. The dual catalyst system according to claim 1, wherein the molar
ratio of the first component to the second component is from 80:20
to 20:80.
3. The catalyst according to claim 2, wherein in the first
component M is a group 4 transition metal.
4. The catalyst according to claim 3, further including an
activator selected from the group consisting of: (i) a complex
aluminum compound of the formula
R.sup.12.sub.2AlO(R.sup.12AlO).sub.mAlR.sup.12.sub.2 wherein each
R.sup.12 is independently selected from the group consisting of
C.sub.1-20 hydrocarbyl radicals and m is from 3 to 50, and
optionally a hindered phenol to provide a molar ratio of
Al:hindered phenol from 2:1 to 5:1 if the hindered phenol is
present; (ii) ionic activators selected from the group consisting
of: (A) compounds of the formula [R.sup.13].sup.+
[B(R.sup.14).sub.4].sup.- wherein B is a boron atom, R.sup.13 is a
cyclic C.sub.5-7 aromatic cation or a triphenyl methyl cation and
each R.sup.14 is independently selected from the group consisting
of phenyl radicals which are unsubstituted or substituted with 3 to
5 substituents selected from the group consisting of a fluorine
atom, a C.sub.1-4 alkyl or alkoxy radical which is unsubstituted or
substituted by a fluorine atom; and a silyl radical of the formula
--Si--(R.sup.15).sub.3; wherein each R.sup.15 is independently
selected from the group consisting of a hydrogen atom and a
C.sub.1-4 alkyl radical; and (B) compounds of the formula
[(R.sup.18).sub.t ZH].sup.+ [B(R.sup.14).sub.4].sup.- wherein B is
a boron atom, H is a hydrogen atom, Z is a nitrogen atom or
phosphorus atom, t is 2 or 3 and R.sup.18 is selected from the
group consisting of C.sub.1-8 alkyl radicals, a phenyl radical
which is unsubstituted or substituted by up to three C.sub.1-4
alkyl radicals, or one R.sup.18 taken together with the nitrogen
atom may form an anilinium radical and R.sup.14 is as defined
above; and (C) compounds of the formula B(R.sup.14).sub.3 wherein
R.sup.14 is as defined above; and (iii) mixtures of (i) and
(ii).
5. The dual catalyst system according to claim 4, wherein both the
first and second catalyst components are supported on the same
support.
6. The dual catalyst system according to claim 5, wherein the
support is an inorganic support or organic support.
7. The dual catalyst system according to claim 6, wherein the
support is silica.
8. The dual catalyst system according to claim 7, wherein the
support has an average particle size from about 10 to 150 microns,
a surface area greater than 100 m.sup.2/g, and a pore volume from
about 0.3 to 5.0 ml/g.
9. The dual catalyst system according to claim 8, wherein in the
first and second component M is selected from the group consisting
of Ti, Hf and Zr.
10. The dual catalyst according to claim<wherein in the second
component L is a cyclopentadienyl type ligand selected from the
group consisting of a C.sub.5-13 ligand containing a 5-membered
carbon ring having delocalized bonding within the ring and bound to
the metal atom through .eta..sup.5 bonds and said ligand being
unsubstituted or up to fully substituted with one or more
substituents selected from the group consisting of C.sub.1-10
hydrocarbyl radicals in which hydrocarbyl substituents are
unsubstituted or further substituted by one or more substituents
selected from the group consisting of a halogen atom and a
C.sub.1-8 alkyl radical; a halogen atom; a C.sub.1-8 alkoxy
radical; a C.sub.6-10 aryl or aryloxy radical; an amido radical
which is unsubstituted or substituted by up to two C.sub.1-8 alkyl
radicals; a phosphido radical which is unsubstituted or substituted
by up to two C.sub.1-8 alkyl radicals; silyl radicals of the
formula --Si--(R).sub.3 wherein each R is independently selected
from the group consisting of hydrogen, a C.sub.1 -8 alkyl or alkoxy
radical, and C.sub.6-10 aryl or aryloxy radicals; and germanyl
radicals of the formula Ge--(R).sub.3 wherein R is as defined
above.
11. The dual catalyst system according to claim 10, wherein in the
second component Y is selected from the group consisting of a
hydrogen atom; a halogen atom, a C.sub.1-10 hydrocarbyl radical; a
C.sub.1-10 alkoxy radical; a C.sub.5-10 aryl oxide radical; each of
which said hydrocarbyl, alkoxy, and aryl oxide radicals may be
unsubstituted by or further substituted by one or more substituents
selected from the group consisting of a halogen atom; a C.sub.1-8
alkyl radical; a C.sub.1-8 alkoxy radical; a C.sub.6-10 aryl or
aryloxy radical; an amido radical which is unsubstituted or
substituted by up to two C.sub.1-8 alkyl radicals.
12. The dual catalyst system according to claim 11, wherein in the
second component the phosphinimine ligand has the formula
((R.sup.21).sub.3P.dbd.N)-- wherein each R.sup.21 is independently
selected from the group consisting of C.sub.1-6 alkyl radicals.
13. The dual catalyst system according to claim 12, wherein in the
second component Cp is selected from the group consisting of a
cyclopentadienyl radical, an indenyl radical and a fluorenyl
radical.
14. The dual catalyst system according to claim 13, wherein in the
second component Y is selected from the group consisting of a
hydrogen atom, a chlorine atom and a C.sub.1-4 alkyl radical.
15. The dual catalyst system according to claim 14, wherein in the
second component the phosphinimine ligand is tris t-butyl
phosphinimine.
16. The dual catalyst according to claim 15, wherein the activator
is a complex aluminum compound wherein R.sup.12 is a methyl radical
and m is from 10 to 40.
17. The dual catalyst according to claim 16, wherein the molar
ratio of Al to transition metal is from 10:1 to 500:1.
18. The dual catalyst according to claim 17, wherein the activator
is a mixture of a complex aluminum compound and a hindered
phenol.
19. The dual catalyst according to claim 18, wherein the molar
ratio of Al:hindered phenol is from 3.25:1 to 4.50:1.
20. The dual catalyst according to claim 19, wherein the hindered
phenol is 2,6-di-t-butyl4-ethyl phenol.
21. The dual catalyst according to claim 15, wherein the activator
is an ionic activator.
22. The dual catalyst according to claim 21, wherein the molar
ratio of transition metal to boron is from 1:1 to 1:3.
23. The dual catalyst according to claim 22, wherein the ionic
activator is tritylborate.
24. The dual catalyst according to claim 20, wherein the molar
ratio of transition metal to boron is from 1:1.05 to 1:1.20.
25. The dual catalyst according to claim 15, wherein the activator
is a mixture of an aluminum compound together with a hindered
phenol and an ionic activator to provide a molar ratio of
transition metal:Al:boron from 1:20:1 to 1:120:3.
26. The dual catalyst according to claim 25, wherein the molar
ratio of Al:hindered phenol is from 3.25:1 to 4.50:1.
27. The dual catalyst according to claim 26, wherein the catalyst
system has a molar ratio of transition metal:Al:boron from 1:30:1
to 1:45:1.5.
28. The dual catalyst according to claim 27, wherein the ionic
activator is tritylborate.
29. The dual catalyst according to claim 28, wherein the hindered
phenol is 2,6-di-t-butyl-4-ethyl phenol.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a dual catalyst system on
the same support.
BACKGROUND OF THE INVENTION
[0002] The original single site catalysts of the mid 1980's, such
as metallocene catalysts, produced resin having a narrow
polydispersity (Mw/Mn) typically in the range from about 2.5 to
3.5. Early on it was recognized that either blending such resins or
the use of different metallocene catalysts in the same reactor
could produce bimodal resins, each component having a narrow
polydispersity and the blend having a broader polydispersity. It
was felt such resins would provide a good balance of processability
and physical properties such as resin toughness. There are an
increasing number of patents and applications in this field.
[0003] U.S. Pat. No. 4,530,914 issued Jul. 23, 1985 to Ewen et al.,
assigned to EXXON Research & Engineering Co. teaches the use in
the same reactor of two metallocene catalysts each having different
propagation and termination rate constants for ethylene
polymerizations. The catalyst combination taught in the patent is
not the same as that contemplated by the present invention.
[0004] There are a number of patents wherein a bimodal resin is
produced having a controlled molecular weight distribution by using
different single site catalysts such as metallocene in two or more
tandem reactors. United States patent application 2002/0045711 in
the name of Backman et al., published Apr. 18, 2002 is illustrative
of this type of art. The reference teaches away from the present
invention in that the present invention contemplates the use of a
single reactor, not tandem reactors.
[0005] U.S. Pat. No. 6,309,997 issued Oct. 30, 2001 teaches an
olefin polymerization catalyst using a phenoxide (preferably a
salicylaldimine) ligand for use in the polymerization of olefins.
The patent does not teach the use of mixed catalysts systems for
bimodal resins nor does it teach process control to adjust the
polymer characteristics such as bimodality and comonomer
incorporation.
[0006] United States patent application 2002/0077431 published Jun.
20, 2002 in the name of Whiteker discloses a process for the
polymerization and oligomerization of olefins in the presence of a
mixed catalyst system in a single reactor. The catalyst system as
disclosed comprises a first component similar to the first
component in the catalyst system of the present invention except
that at least one of substituents R.sup.3, R.sup.4, R.sup.5,
R.sup.8, R.sup.9 and R.sup.10 must have a Hammett .sigma..sub.92
value (Hansch et al., Chem. Rev. 1991, 91, 165) greater than 0.2
(i.e. at least one of these substituents needs to be a sufficiently
electron withdrawing group (e.g. CF.sub.3, Br, etc.)). In the
catalysts and process according to the present invention none of
R.sup.3, R.sup.4, R.sup.5, R.sup.8, R.sup.9 and R.sup.10 have a
Hammett (.sigma..sub..rho.) value of greater than 0.2. Further the
reference fails to teach or suggest the molecular weight
distribution of the components in the resulting polymer may be
altered or controlled by altering or controlling the reaction
conditions.
[0007] The present invention seeks to provide novel useful
catalysts suitable for the polymerization of bimodal polyolefins
(e.g. polyethylene) having reverse or partial reverse comonomer
incorporation.
SUMMARY OF THE INVENTION
[0008] The present invention provides a dual catalyst system
suitable for producing a bimodal resin having at least one higher
molecular weight fraction having a greater comonomer incorporation
than that of a lower molecular weight fraction wherein:
[0009] (i) the first component of which comprises a catalyst of the
formula: ##STR1## wherein M is a transition metal, preferably a
group 4 transition metal, most preferably selected from the group
consisting of Ti, Hf and Zr; R.sup.1 and R.sup.6 are independently
selected from the group consisting of a hydrogen atom, alkyl
radicals having up to 15, preferably from 1 to 8, most preferably
from 1 to 6 carbon atoms, aryl radicals having up to 25, preferably
from 6 to 18, most preferably from 6 to 12 carbon atoms, alkoxy
radicals having up to 15, preferably from 1 to 8, most preferably
from 1 to 6 carbon atoms, and amido radicals which are
unsubstituted or substituted by up to two alkyl radicals containing
up to 15, preferably from 1 to 8, most preferably from 1 to 6
carbon atoms, R.sup.2 and R.sup.7 are independently selected from
the group consisting of alkyl radicals having up to 15, preferably
from 1 to 8, most preferably from 1 to 6 carbon atoms, aryl
radicals having up to 25, preferably from 6 to 18, most preferably
from 6 to 12 carbon atoms and silyl radicals of the formula
Si(R.sup.11).sub.3 wherein each R.sup.11 is independently selected
from the group consisting of alkyl radicals having up to 15,
preferably from 1 to 8, most preferably from 1 to 6 carbon atoms,
and aryl radicals having up to 25, preferably from 6 to 18, most
preferably from 6 to 12 carbon atoms; R.sup.3, R.sup.4, R.sup.5,
R.sup.8, R.sup.9 and R.sup.10 are independently selected from the
group consisting of a hydrogen atom, a heteroatom containing group
having up to 20, preferably from 1 to 18, most preferably from 1 to
12 carbon atoms, and a hydrocarbon group containing up to 25 carbon
atoms, provided that none of these groups has a Hammett
.sigma..sub.92 value greater than 0.20; X and X' are activatable
groups;
[0010] (ii) the second component of which comprises a catalyst of
the formula: ##STR2## wherein M is a group 4 metal; Pl is a
phosphinimine ligand; L is a monoanionic ligand selected from the
group consisting of a cyclopentadienyl-type ligand or a bulky
heteroatom ligand; Y is an activatable ligand; m is 1 or 2; n is 0
or 1; and p is an integer and the sum of m+n+p equals the valence
state of M.
[0011] The present invention further provides a gas phase process
for controlling the ratio of high molecular weight polymer to low
molecular weight polymer in a single reactor at a temperature from
50 to 120.degree. C. of a reaction mixture comprising one or more
of hydrogen, nitrogen, C.sub.1-7 non polymerizable hydrocarbons,
and C.sub.2-8 olefins polymerized in the presence of a dual
catalyst as described above, which comprises one or more steps
selected from the group consisting of:
[0012] (a) altering the temperature of the reaction by at least
2.degree. C. within the range from 50 to 120.degree. C.;
[0013] (b) altering the partial pressure of the hydrogen component
of the reaction mixture by at least 0.02 psi (0.138 KPa);
[0014] (c) altering the partial pressure of one or more of the
C.sub.2-8 olefins in the reaction mixture by not less than 10 psi
(68.94 KPa); and
[0015] (d) altering the amount of non polymerizable hydrocarbon in
the reaction mixture by not less than 0.5 mole %.
[0016] In a slurry process (a) through (c) would be used to control
the polymer characteristics.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a GPC-FTIR profile of the resin produced in
Example 1.
[0018] FIG. 2 is a GPC-FTIR profile of the resin produced in
Example 2.
[0019] FIG. 3 is a GPC-FTIR profile of the resin produced in
Example 3.
[0020] FIG. 4 is a GPC-FTIR profile of the resin produced in
Example 4.
[0021] FIG. 5 is a GPC-FTIR profile of the resin produced in
Example 5.
DETAILED DESCRIPTION
[0022] As used in this specification the following words or phrases
have the following meanings.
[0023] Polydispersity is the ratio of the weight average molecular
weight (as determined by GPC) to the number average molecular
weight (as determined by GPC) (i.e. Mw/Mn) of any component in the
blend or the blend per se.
[0024] Cyclopentadienyl refers to a 5-member carbon ring having
delocalized bonding within the ring and typically being bound to
the active catalyst site, generally a group 4 metal (M) through
.eta..sup.5-bonds.
[0025] The phrase mixed catalyst or dual catalyst or catalyst
system on a single support means that both components are on the
same support (e.g. the catalyst components are deposited (either
sequentially or concurrently) on the same support particles). It
does not mean that the catalyst is a blend of two or more catalysts
each of which happen to be on the same type of or a similar type of
support.
[0026] The phrase reverse or partial reverse comonomer
incorporation means that on deconvolution of the GPC-FTIR (or TREF)
data (profiles) (typically using molecular weight distribution
segments of not less than 10,000) there is one or more higher
molecular component having a higher comonomer incorporation than
the comonomer incorporation in one or more lower molecular
segments. If the comonomer incorporation is rising with molecular
weight the distribution would be reverse. However the comonomer
incorporation may rise with increasing molecular weight then
decline in which case the comonomer distribution would be partially
reverse (or partially regular).
[0027] The gas phase polymerization of olefins and particularly
alpha-olefins has been known for at least about 30 years. Generally
a gaseous mixture comprising from 0 to 15 mole % of hydrogen, from
0 to 30 mole % of one or more C.sub.3-8 alpha-olefins, from 15 to
100 mole % of ethylene, and from 0 to 75 mole % of
non-polymerizable gas at a temperature from 50.degree. C. to
120.degree. C., preferably from 60.degree. C. to 120.degree. C.,
most preferably from 75.degree. C. to about 110.degree. C., and at
pressures typically not exceeding 3,500 kPa (about 500 psi),
preferably not greater than 2,400 kPa (about 350 psi) are
polymerized in the presence of a mixed catalyst system on a single
support in a single rector.
[0028] The slurry phase polymerization of olefins has been known
for about 30 years. Generally a mixture comprising from 0 to 15
mole % of hydrogen, from 0 to 30 mole % of one or more C.sub.3-8
alpha olefins, from 15 to 100 mole % of ethylene, and from 0 to 75
mole % of an inert gas is dissolved in an inert hydrocarbyl diluent
such as C.sub.4-10 hydrocabons and C.sub.6-10 aryl or arylalkyl
hydrocarbons. The mixture is then polymerized at a temperature from
50.degree. C. to 120.degree. C., preferably from 60.degree. C. to
120.degree. C., most preferably from 70.degree. C. to about
110.degree. C., and at pressures typically not exceeding 3,500 kPa
(about 500 psi), preferably not greater than 2,400 kPa (about 350
psi) is polymerized in the presence of a mixed catalyst system on a
single support in a single rector.
[0029] Suitable olefin monomers may be ethylene and C.sub.3-20
mono- and di-olefins. Preferred monomers include ethylene and
C.sub.3-8 alpha olefins which are unsubstituted or substituted by
up to two C.sub.1-6 alkyl radicals. Illustrative non-limiting
examples of such alpha olefins are one or more of propylene,
1-butene, 1-pentene, 1-hexene and 1-octene.
[0030] The polyethylene polymers which may be prepared in
accordance with the present invention typically comprise not less
than 60, preferably not less than 70, most preferably not less than
80 weight % of ethylene with the balance being one or more
C.sub.3-8 alpha olefins, preferably selected from the group
consisting of 1-butene, 1-hexene and 1-octene.
[0031] The polymers prepared in accordance with the present
invention have a bimodal or multimodal molecular weight
distribution. Overall, the weight average molecular weight (Mw)
will preferably be greater than about 50,000 ranging up to
10.sup.7, preferably 10.sup.5 to 10.sup.7. There will be a lower
molecular weight component seen as a peak or shoulder on a GPC
analysis and there will be one or more higher molecular weight
components also seen as a separate peak or shoulder on a GPC
analysis. Generally the lower molecular weight component will be
present in an amount from 20 to 80, preferably from 30 to 70, most
preferably from 35 to 65 weight % of the total bimodal resin. The
high molecular component may be present in amounts from 80 to 20,
preferably 70 to 30, most preferably from about 65 to 35 weight %
of the total polymer.
[0032] The low molecular weight polyethylene may have a weight
average molecular weight greater than 5,000, typically from 10,000
to 140,000, preferably from about 15,000 to about 100,000, most
preferably from about 20,000 to 100,000 as estimated by
deconvolution of a GPC curve. The low molecular weight polyethylene
may have a polydispersity (Mw/Mn) greater than about 3, typically
from 3 to 15, preferably from about 5 to 12.
[0033] The high molecular weight polyethylene may have a weight
average molecular a weight greater than 200,000, typically from
250,000 to 600,000 as determined by deconvolution of a GPC curve.
The high molecular weight polyethylene may have a polydispersity
(Mw/Mn) less than about 10, typically from 2 to 8.
[0034] The catalyst system of the present invention may be
supported on a refractory support or an organic support (including
polymeric support). That is both catalyst components are supported
on the same refractory support or an organic support (e.g.
polymeric). Some refractories include silica which may be treated
to reduce surface hydroxyl groups and alumina. The support or
carrier may be a spray-dried silica. Generally the support will
have an average particle size from about 0.1 to about 1000,
preferably from about 10 to 150 microns. The support typically will
have a surface area of at least about 100 m.sup.2/g, preferably
from about 150 to 1,500 m.sup.2/g. The pore volume of the support
should be at least 0.2, preferably from about 0.3 to 5.0 ml/g.
[0035] Generally the refractory or inorganic support may be heated
at a temperature of at least 200.degree. C. for up to 24 hours,
typically at a temperature from 500.degree. C. to 800.degree. C.
for about 2 to 20, preferably 4 to 10 hours. The resulting support
will be free of adsorbed water and should have a surface hydroxyl
content from about 0.1 to 5 mmol/g of support, preferably from 0.5
to 3 mmol/g.
[0036] A silica suitable for use in the present invention has a
high surface area and is amorphous. For example, commercially
available silicas are marketed under the trademark of Sylopol.RTM.
958 and 955 by the Davison Catalysts, a Division of W. R. Grace and
Company and ES-70W by Ineos Silica.
[0037] The amount of the hydroxyl groups in silica may be
determined according to the method disclosed by J. B. Peri and A.
L. Hensley, Jr., in J. Phys. Chem., 72 (8), 2926, 1968, the entire
contents of which are incorporated herein by reference.
[0038] While heating is the most preferred means of removing OH
groups inherently present in many carriers, such as silica, the OH
groups may also be removed by other removal means, such as chemical
means. For example, a desired proportion of OH groups may be
reacted with a suitable chemical agent, such as a hydroxyl reactive
aluminum compound (e.g. triethyl aluminum) or a silane compound.
This method of treatment has been disclosed in the literature and
two relevant examples are: U.S. Pat. No. 4,719,193 to Levine in
1988 and by Noshay A. and Karol F. J. in Transition Metal Catalyzed
Polymerizations, Ed. R. Quirk, 396, 1989. For example, the support
may be treated with an aluminum compound of the formula
Al((O).sub.aR.sup.1).sub.bX.sub.3-b wherein a is either 0 or 1, b
is an integer from 1 to 3, R.sup.1 is a C.sub.1-8 alkyl radical,
and X is a chlorine atom. The amount of aluminum compound is such
that the amount of aluminum on the support prior to adding the
remaining catalyst components will be from about 0 to 2.5 weight %,
preferably from 0 to 2.0 weight % based on the weight of the
support.
[0039] The polymeric support may be cross linked polystyrene
containing up to about 20 weight % preferably less than 10 weight
%, most preferably from about 2 to 8 weight % of a cross linking
agent such as divinyl benzene.
[0040] In accordance with the present invention the two catalysts
are deposited on the same support (i.e. both catalysts must be on
each particle of support). The catalysts may be used in a molar
ratio of the active transition metal of the first catalyst to the
second catalyst from 80:20 to 20:80 preferably from 60:40 to 40:60.
While the present invention is directed to both catalysts being on
the same support, it is expected it would be possible to achieve
similar results by blending two catalysts on similar or comparable
supports to provide the same ratio of catalysts.
[0041] In accordance with the present invention the first catalyst
comprises a catalyst of the formula I: ##STR3## wherein M is a
Group IV transition metal preferably Ti or Zr; R.sup.1 and R.sup.6
are independently selected from the group consisting of a hydrogen
atom, alkyl radicals having up to 15, preferably from 1 to 8, most
preferably from 1 to 6 carbon atoms, aryl radicals having up to 25,
preferably from 6 to 18, most preferably from 6 to 12 carbon atoms,
alkoxy radicals having up to 15, preferably from 1 to 8, most
preferably from 1 to 6 carbon atoms, and amido radicals which are
unsubstituted or substituted by up to two alkyl radicals containing
up to 15, preferably from 1 to 8, most preferably from 1 to 6
carbon atoms, R.sup.2 and R.sup.7 are independently selected from
the group consisting of alkyl radicals having up to 15, preferably
from 1 to 8, most preferably from 1 to 6 carbon atoms, aryl
radicals having up to 25, preferably from 6 to 18, most preferably
from 6 to 12 carbon atoms and silyl radicals of the formula
Si(R.sup.11).sub.3 wherein each R.sup.11 is independently selected
from the group consisting of alkyl radicals having up to 15,
preferably from 1 to 8, most preferably from 1 to 6 carbon atoms,
and aryl radicals having up to 25, preferably from 6 to 18, most
preferably from 6 to 12 carbon atoms; R.sup.3, R.sup.4, R.sup.5,
R.sup.8, R.sup.9 and R.sup.10 are independently selected from the
group consisting of a hydrogen atom, a heteroatom containing group
having up to 20, preferably from 1 to 18, most preferably from 1 to
12 carbon atoms, and a hydrocarbon group containing up to 25 carbon
atoms, provided that none of these groups has a Hammett
.sigma..sub.92 value greater than 0.20; X and X' are activatable or
leaving groups.
[0042] In the first catalyst (first component) preferably R.sup.3,
R.sup.4, R.sup.5, R.sup.8, R.sup.9 and R.sup.10 are selected from
the group consisting of a hydrogen atom and C.sub.1-15, preferably
C.sub.1-8, most preferably C.sub.1-6 alkoxy radicals. Preferably
R.sup.3, R.sup.5, R.sup.8 and R.sup.10 are hydrogen.
[0043] As noted above none of R.sup.3, R.sup.4, R.sup.5, R.sup.8,
R.sup.9 and R.sup.10 has a Hammett .sigma..sub..rho. value (Hansch
et al., Chem Rev. 1991, 91, 165) greater than 0.2.
[0044] Activatable or leaving groups are well known to those
skilled in the art. Generally, they may be selected from the group
consisting of a halogen atom, alkyl radicals having up to 15,
preferably from 1 to 8, most preferably from 1 to 6 carbon atoms,
aryl radicals having up to 25, preferably from 6 to 18, most
preferably from 6 to 12 carbon atoms, alkoxy radicals having up to
15, preferably from 1 to 8, most preferably from 1 to 6 carbon
atoms, amido radicals which are unsubstituted or substituted by up
to two alkyl radicals containing up to 15, preferably from 1 to 8,
most preferably from 1 to 6 carbon atoms, and phenoxy radicals
having up to 18, preferably from 6 to 12 carbon atoms.
[0045] The synthesis of desired ligands of the first catalyst can
be accomplished by reaction of salicylaldehydes with amines.
Preparation of the requisite salicylaldehydes can be accomplished
using standard synthetic techniques.
[0046] Metallation of the ligands can be accomplished by reaction
with basic reagents such as Zr(CH.sub.2Ph).sub.4. Reaction of the
ligands with Zr(CH.sub.2Ph).sub.4 occurs with elimination of
toluene. Alternately, ligands can be deprotonated with reagents
such as BuLi, KH or Na metal and then reacted with metal halides,
such as ZrCl.sub.4.
[0047] The second component of the catalyst system (second
catalyst) is a catalyst of the formula II: ##STR4## wherein M is a
group 4 metal; Pl is a phosphinimine ligand; L is a monoanionic
ligand selected from the group consisting of a
cyclopentadienyl-type ligand or a bulky heteroatom ligand; Y is an
activatable ligand; m is 1 or 2; n is 0 or 1; and p is an integer
and the sum of m+n+p equals the valence state of M.
[0048] The preferred metals (M) are from Group 4 (especially
titanium, hafnium or zirconium) with titanium being most
preferred.
[0049] The phosphinimine ligand is defined by the formula: ##STR5##
wherein each R.sup.21 is independently selected from the group
consisting of a hydrogen atom; a halogen atom; C.sub.1-20,
preferably C.sub.1-10 hydrocarbyl radicals which are unsubstituted
by or further substituted by a halogen atom; a C.sub.1-8 alkoxy
radical; a C.sub.6-10 aryl or aryloxy radical; an amido radical; a
silyl radical of the formula: --Si--(R.sup.22).sub.3 wherein each
R.sup.22 is independently selected from the group consisting of
hydrogen, a C.sub.1-8 alkyl or alkoxy radical, and C.sub.6-10 aryl
or aryloxy radicals; and a germanyl radical of the formula:
Ge--(R.sup.22).sub.3 wherein R.sup.22 is as defined above.
[0050] In the second catalyst preferably Y is selected from the
group consisting of a hydrogen atom; a halogen atom, a C.sub.1-10
hydrocarbyl radical; a C.sub.1-10 alkoxy radical; a C.sub.5-10 aryl
oxide radical; each of which said hydrocarbyl, alkoxy, and aryl
oxide radicals may be unsubstituted by or further substituted by
one or more substituents selected from the group consisting of a
halogen atom; a C.sub.1-8 alkyl radical; a C.sub.1-8 alkoxy
radical; a C.sub.6-10 aryl or aryloxy radical; an amido radical
which is unsubstituted or substituted by up to two C.sub.1-8 alkyl
radicals; and a phosphido radical which is unsubstituted or
substituted by up to two C.sub.1-8 alkyl radicals. Most preferably
Y is selected from the group consisting of a hydrogen atom, a
chlorine atom and a C.sub.1-4 alkyl radical.
[0051] In the second component of the catalyst system (second
catalyst) L is a monoanionic ligand selected from the group
consisting of a cyclopentadienyl-type ligand or a bulky heteroatom
ligand, preferably L is a cyclopentadienyl type ligand.
[0052] As used herein, the term "bulky heteroatom ligand" refers to
a ligand which contains at least one heteroatom selected from the
group consisting of boron, nitrogen, oxygen, phosphorus or sulfur.
The heteroligand may be sigma or pi-bonded to the metal. Exemplary
heteroligands include ketimide ligands, silicone-containing
heteroligands, amido ligands, alkoxy ligands, boron heterocyclic
ligands (e.g. borabenzene ligands) and phosphole ligands, as all
described below.
[0053] As used herein, the term "ketimide ligand" refers to a
ligand which:
[0054] (a) is bonded to the transition metal via a metal-nitrogen
atom bond;
[0055] (b) has a single substituent on the nitrogen atom, (where
this single substituent is a carbon atom which is doubly bonded to
the N atom); and
[0056] (c) has two substituents Sub 1 and Sub 2 (described below)
which are bonded to the carbon atom.
[0057] Conditions a, b and c are illustrated below: ##STR6##
[0058] The substituents "Sub 1" and "Sub 2" may be the same or
different and can be bonded to each other to form a ring. Exemplary
substituents include hydrocarbyls having from 1 to 20 carbon atoms,
silyl groups, amido groups and phosphido groups. For reasons of
cost and convenience it is preferred that these substituents both
be hydrocarbyl radicals, especially simple alkyl radicals (e.g.
C.sub.1-6, preferably C.sub.1-4) and most preferably tertiary
butyl.
[0059] Silicon containing heteroligands are defined by the formula:
--(.mu.)SiR.sub.xR.sub.yR.sub.z wherein the--denotes a bond to the
transition metal and .mu. is sulfur or oxygen.
[0060] The substituents on the Si atom, namely R.sub.x, R.sub.y and
R.sub.z are required in order to satisfy the bonding orbital of the
Si atom. The use of any particular substituent R.sub.x, R.sub.y or
R.sub.z is not especially important to the success of this
invention. It is preferred that each of R.sub.x, R.sub.y and
R.sub.z is a C.sub.1-2 hydrocarbyl group (i.e. methyl or ethyl)
simply because such materials are readily synthesized from
commercially available materials.
[0061] The term "amido" is meant to convey its broad, conventional
meaning. Thus, these ligands are characterized by (a) a
metal-nitrogen bond; and (b) the presence of two substituents,
which are typically simple alkyl (C.sub.1-6, preferably C.sub.1-4)
or silyl groups on the nitrogen atom.
[0062] The terms "alkoxy" and "aryloxy" are also intended to convey
their conventional meaning. Thus, these ligands are characterized
by (a) a metal oxygen bond; and (b) the presence of a hydrocarbyl
group bonded to the oxygen atom. The hydrocarbyl group may be a
C.sub.1-10 straight chained, branched or cyclic alkyl radical or a
C.sub.6-13 aromatic radical which radicals are unsubstituted or
further substituted by one or more C.sub.1-4 alkyl radicals (e.g.
2,6 di-tertiary butyl phenoxy).
[0063] Boron heterocyclic ligands are characterized by the presence
of a boron atom in a closed ring ligand (e.g. borabenzene ligands
which are unsubstituted or may be substituted by one or more
halogen atoms, C.sub.1-10 alkyl group, C.sub.1-10 alkyl group
containing a hetero atom (e.g. O, or N atoms)). This definition
includes heterocyclic ligands which may also contain a nitrogen
atom in the ring. These ligands are well known to those skilled in
the art of olefin polymerization and are fully described in the
literature (see, for example, U.S. Pat. Nos. 5,637,659; 5,554,775
and the references cited therein).
[0064] The term "phosphole" is also meant to convey its
conventional meaning. "Phospholes" are cyclic dienyl structures
having four carbon atoms and one phosphorus atom in the closed
ring. The simplest phosphole is C.sub.4PH.sub.4 (which is analogous
to cyclopentadiene with one carbon in the ring being replaced by
phosphorus). The phosphole ligands may be substituted with, for
example, C.sub.1-20 hydrocarbyl radicals (which may, optionally,
contain halogen substituents); phosphido radicals; amido radicals;
or silyl or alkoxy radicals. Phosphole ligands are also well known
to those skilled in the art of olefin polymerization and are
described as such in U.S. Pat. No. 5,434,116 (Sone, to Tosoh).
[0065] In the second component of the catalyst system (second
catalyst) preferably L is a cyclopentadienyl-type ligand.
Preferably L is a 5-membered carbon ring having delocalized bonding
within the ring and bound to the metal atom through .mu..sup.5
bonds and said ligand being unsubstituted or up to fully
substituted with one or more substituents selected from the group
consisting of C.sub.1-10 hydrocarbyl radicals in which hydrocarbyl
substituents are unsubstituted or further substituted by one or
more substituents selected from the group consisting of a halogen
atom and a C.sub.1-8 alkyl radical; a halogen atom; a C.sub.1-8
alkoxy radical; a C.sub.6-10 aryl or aryloxy radical; an amido
radical which is unsubstituted or substituted by up to two
C.sub.1-8 alkyl radicals; a phosphido radical which is
unsubstituted or substituted by up to two C.sub.1-8 alkyl radicals;
silyl radicals of the formula --Si--(R).sub.3 wherein each R is
independently selected from the group consisting of hydrogen, a
C.sub.1-8 alkyl or alkoxy radical, and C.sub.6-10 aryl or aryloxy
radicals; and germanyl radicals of the formula Ge--(R).sub.3
wherein R is as defined above. Most preferably the cyclopentadienyl
type ligand is selected from the group consisting of a
cyclopentadienyl radical, an indenyl radical and a fluorenyl
radical.
[0066] The catalyst systems (e.g. first and second catalyst) in
accordance with the present invention may be activated with an
activator selected from the group consisting of:
[0067] (i) a complex aluminum compound of the formula
R.sup.12.sub.2AlO(R.sup.12AlO).sub.mAlR.sup.12.sub.2 wherein each
R.sup.12 is independently selected from the group consisting of
C.sub.1-20 hydrocarbyl radicals and m is from 3 to 50, and
optionally a hindered phenol to provide a molar ratio of
Al:hindered phenol from 2:1 to 5:1 if the hindered phenol is
present;
[0068] (ii) ionic activators selected from the group consisting of:
[0069] (A) compounds of the formula [R.sup.13].sup.+
[B(R.sup.14).sub.4].sup.- wherein B is a boron atom, R.sup.13 is a
cyclic C.sub.5-7 aromatic cation or a triphenyl methyl cation and
each R.sup.14 is independently selected from the group consisting
of phenyl radicals which are unsubstituted or substituted with 3 to
5 substituents selected from the group consisting of a fluorine
atom, a C.sub.1-4 alkyl or alkoxy radical which is unsubstituted or
substituted by a fluorine atom; and a silyl radical of the formula
--Si--(R.sup.15).sub.3; wherein each R.sup.15 is independently
selected from the group consisting of a hydrogen atom and a
C.sub.1-4 alkyl radical; and [0070] (B) compounds of the formula
[(R.sup.18).sub.t ZH].sup.+ [B(R.sup.14).sub.4].sup.- wherein B is
a boron atom, H is a hydrogen atom, Z is a nitrogen atom or
phosphorus atom, t is 2 or 3 and R.sup.18 is selected from the
group consisting of C.sub.1-8 alkyl radicals, a phenyl radical
which is unsubstituted or substituted by up to three C.sub.1-4
alkyl radicals, or one R.sup.18 taken together with the nitrogen
atom may form an anilinium radical and R.sup.14 is as defined
above; and [0071] (C) compounds of the formula B(R.sup.14).sub.3
wherein R.sup.14 is as defined above; and
[0072] (iii) mixtures of (i) and (ii).
[0073] Preferably the activator is a complex aluminum compound of
the formula R.sup.12.sub.2AlO(R.sup.12AlO).sub.mAlR.sup.12.sub.2
wherein each R.sup.12 is independently selected from the group
consisting of C.sub.1-20 hydrocarbyl radicals and m is from 3 to
50, and optionally a hindered phenol to provide a molar ratio of
Al:hindered phenol from 2:1 to 5:1 if the hindered phenol is
present. In the aluminum compound preferably, R.sup.12 is methyl
radical and m is from 10 to 40. The preferred molar ratio of
Al:hindered phenol, if it is present, is from 3.25:1 to 4.50:1.
Preferably the phenol is substituted in the 2, 4 and 6 position by
a C.sub.2-6 alkyl radical. Desirably the hindered phenol is
2,6-di-tert-butyl-4-ethyl-phenol.
[0074] The aluminum compounds (alumoxanes) are typically used in
substantial molar excess compared to the amount of metal in the
catalyst. Aluminum:transition metal molar ratios of from 10:1 to
10,000:1 are preferred, most preferably 10:1 to 500:1 especially
from 10:1 to 50:1.
[0075] Ionic activators are well known to those skilled in the art.
The "ionic activator" may abstract one activatable ligand so as to
ionize the catalyst center into a cation, but not to covalently
bond with the catalyst and to provide sufficient distance between
the catalyst and the ionizing activator to permit a polymerizable
olefin to enter the resulting active site.
[0076] Examples of ionic activators include: [0077]
triethylammonium tetra(phenyl)boron, [0078] tripropylammonium
tetra(phenyl)boron, [0079] tri(n-butyl)ammonium tetra(phenyl)boron,
[0080] trimethylammonium tetra(p-tolyl)boron, [0081]
trimethylammonium tetra(o-tolyl)boron, [0082] tributylammonium
tetra(pentafluorophenyl)boron, [0083] tripropylammonium
tetra(o,p-dimethylphenyl)boron, [0084] tributylammonium
tetra(m,m-dimethylphenyl)boron, [0085] tributylammonium
tetra(p-trifluoromethylphenyl)boron, [0086] tributylammonium
tetra(pentafluorophenyl)boron, [0087] tri(n-butyl)ammonium
tetra(o-tolyl)boron, [0088] N,N-dimethylanilinium
tetra(phenyl)boron, [0089] N,N-diethylanilinium tetra(phenyl)boron,
[0090] N,N-diethylanilinium tetra(phenyl)n-butylboron, [0091]
di-(isopropyl)ammonium tetra(pentafluorophenyl)boron, [0092]
dicyclohexylammonium tetra(phenyl)boron, [0093]
triphenylphosphonium tetra(phenyl)boron, [0094]
tri(methylphenyl)phosphonium tetra(phenyl)boron, [0095]
tri(dimethylphenyl)phosphonium tetra(phenyl)boron, [0096]
tropillium tetrakispentafluorophenyl borate, [0097]
triphenylmethylium tetrakispentafluorophenyl borate, [0098]
tropillium phenyltrispentafluorophenyl borate, [0099]
triphenylmethylium phenyltrispentafluorophenyl borate, [0100]
benzene (diazonium) phenyltrispentafluorophenyl borate, [0101]
tropillium tetrakis (2,3,5,6-tetrafluorophenyl) borate, [0102]
triphenylmethylium tetrakis (2,3,5,6-tetrafluorophenyl) borate,
[0103] tropillium tetrakis (3,4,5-trifluorophenyl) borate, [0104]
benzene (diazonium) tetrakis (3,4,5-trifluorophenyl) borate, [0105]
tropillium tetrakis (1,2,2-trifluoroethenyl) borate, [0106]
triphenylmethylium tetrakis (1,2,2-trifluoroethenyl) borate, [0107]
tropillium tetrakis (2,3,4,5-tetrafluorophenyl) borate, and [0108]
triphenylmethylium tetrakis (2,3,4,5-tetrafluorophenyl) borate.
[0109] Readily commercially available ionic activators include:
[0110] N,N-dimethylaniliniumtetrakispentafluorophenyl borate;
[0111] triphenylmethylium tetrakispentafluorophenyl borate
(tritylborate); and trispentafluorophenyl borane.
[0112] The ionic activators may be used in amounts to provide a
molar ratio of transition metal to boron that will be from 1:1 to
1:6 preferably from 1:1 to 1:2.
[0113] As noted above, the reaction mixture in a gas phase process
typically comprises from 0 to 15 mole % of hydrogen, from 0 to 30
mole % of one or more C.sub.3-8 alpha-olefins, from 15 to 100 mole
% of ethylene, and from 0 to 75 mole % of one or more non reactive
gases. The non reactive gas may be selected from the group
consisting of nitrogen, a C.sub.1-7 non polymerizable hydrocarbon
such as an alkane (e.g. iso-pentane) or a mixture thereof.
[0114] Applicants have found in polymerizations using the catalyst
of the present invention that it is possible to control the ratio
of the high and low molecular weight components and the comonomer
content in the high and low molecular weight fractions merely by
controlling (changing) one or more of the following conditions: one
or more steps selected from the group consisting of:
[0115] (a) altering the temperature of the reaction by at least
1.degree. C., typically from 3.degree. C. to 20.degree. C., most
preferably from 4.degree. C. to 12.degree. C. within the range from
50 to 120.degree. C.;
[0116] (b) altering the partial pressure of the hydrogen component
of the reaction mixture by at least 0.02 psi (0.138 KPa); typically
from 0.05 to 1 psi (0.345 to 6.894 KPa);
[0117] (c) altering the partial pressure of ethylene in the
reaction mixture by not less than 10 psi (69 KPa) typically from 15
to 50 psi (103.4 KPa to 344.8KPa); and
[0118] (d) altering the amount of non polymerizable hydrocarbon in
the reaction mixture by not less than 0.5 mole %, typically from 1
to 20, most preferably form 3 to 12 mole %.
[0119] Generally in conventional processes the comonomer tends to
be more highly incorporated in to the lower molecular weight
components in the product (e.g. there are higher molecular weight
components having lower comonomer incorporation). However, the
process of the present invention permits the comonomer to be
incorporated in a manner such that there is more comonomer in the
higher molecular weight segments of the polymer (sometimes called
reverse comonomer incorporation). The comonomer distribution could
be a mixture of the above types. That is, the comonomer
incorporation could rise (or fall) until a certain molecular weight
is obtained and then it could fall (or rise) with increasing
molecular weight of the polymer (resulting in a peak or a valley).
The reaction takes place in a single gas phase or slurry phase
reactor. The product is removed from the reactor by conventional
means and separated from diluent and/or residual monomers and
further treated.
[0120] The resulting resin may typically be compounded either by
the manufacturer or the converter (e.g. the company converting the
resin pellets into the final product). The compounded polymer may
contain fillers, pigments and other additives. Typically the
fillers are inert additives such as clay, talc, TiO.sub.2 and
calcium carbonate which may be added to the polyolefin in amounts
from 0 weight % up to about 50 weight %, preferably less than 30
weight %. The resin may contain typical amounts of antioxidants and
heat and light stabilizers such as combinations of one or more of
hindered phenols, phosphates, phosphites and phosphonites typically
in amounts of less than 0.5 weight % based on the weight of the
resin. Pigments such as carbon black may also be added to the resin
in small amounts.
[0121] In the manufacture of pipe and other products, the
polyethylene resin blend may contain a nucleating agent in amounts
from about 1,500 to about 10,000 parts per million (ppm) based on
the weight of the polyolefin. Preferably the nucleating agent is
used in amounts from 2,000 to 8,000 ppm, most preferably from 2,000
to 5,000 ppm based on the weight of the polyolefin.
[0122] The nucleating agent may be selected from the group
consisting of dibenzylidene sorbitol, di (p-methyl benzylidene)
sorbitol, di (o-methyl benzylidene) sorbitol, di
(p-ethylbenzylidene) sorbitol, bis (3,4-dimethyl benzylidene)
sorbitol, bis (3,4-diethylbenzylidene) sorbitol and bis
trimethylbenzylidene) sorbitol. One commercially available
nucleating agent is bis (3,4-dimethyl benzylidene) sorbitol.
[0123] The polymer may be converted into sheet material such as
blown or cast film (such as geomembranes), extruded articles such
as pipes, rotomolded articles such as drums, tanks and sporting
goods such as kayaks, blow molded articles such as bottles and
small jars.
[0124] The present invention will now be illustrated by the
following non-limiting examples.
EXAMPLES
Experimental
[0125] In the experiments the following abbreviations were used.
[0126] THF=tetrahydrofuran [0127] TMS=trimethyl silyl
[0128] Molecular weight distribution and molecular weight averages
(Mw, Mn, Mz) of resins were determined using high temperature Gel
Permeation Chromatography (GPC) according to the ASTM D6474:
"Standard Test Method for Determining Molecular Weight Distribution
and Molecular Weight Averages of Polyolefins". The system was
calibrated using the 16 polystyrene standards (Mw/Mn<1.1) in Mw
range 5.times.10.sup.3 to 8.times.10.sup.6 and 3 hydrocarbon
Standards C.sub.60, C.sub.40, and C.sub.20.
[0129] The operating conditions are listed below: [0130] GPC
instrument: Polymer Laboratories.RTM. 220 equipped with a
refractive index detector [0131] Software: Viscotek.RTM. DM 400
Data Manager with Trisec.RTM. software [0132] Columns: 4
Shodex.RTM. AT-800/S series cross-linked styrene-divinylbenzene
with pore sizes 10.sup.3 .ANG., 10.sup.4 .ANG., 10.sup.5 .ANG.,
10.sup.6 .ANG. [0133] Mobile Phase: 1,2,4-trichlorobenzene [0134]
Temperature: 140.degree. C. [0135] Flow Rate: 1.0 ml/min [0136]
Sample Preparation: Samples were dissolved in
1,2,4-trichloro-benzene by heating on a rotating wheel for four
hours at 150.degree. C. [0137] Sample Filtration: No [0138] Sample
Concentration: 0.1% (w/v) The determination of branch frequency as
a function of molecular weight was carried out using high
temperature Gel Permeation Chromatography (GPC) and FT-IR of the
eluent. Polyethylene standards with a known branch content,
polystyrene and hydrocarbons with a known molecular weight were
used for calibration.
[0139] Operating conditions are listed below: [0140] GPC
instrument: Waters.RTM. 150 equipped with a refractive index
detector [0141] IR Instrument: Nicolet Magna.RTM. 750 with a
Polymer Labs.RTM. flow cell. [0142] Software: Omnic.RTM. 5.1 FT-IR
[0143] Columns: 4 Shodex.RTM. AT-800/S series cross-linked
styrene-divinylbenzene with pore sizes 10.sup.3 .ANG., 10.sup.4
.ANG., 10.sup.5 .ANG., 10.sup.6 .ANG. [0144] Mobile Phase:
1,2,4-Trichlorobenzene [0145] Temperature: 140.degree. C. [0146]
Flow Rate: 1.0 ml/min [0147] Sample Preparation: Samples were
dissolved in 1,2,4-trichlorobenzene by heating on a rotating wheel
for five hours at 150.degree. C. [0148] Sample Filtration: No
[0149] Sample Concentration: 4 mg/g Synthesis of Catalyst Component
1
[0150] EtMgBr (100 mL, 3M solution in diethyl ether) was added
dropwise to a solution of 4-methoxy-2-tert-butyl-phenol (290 mol)
in tetrahydrofuran (THF) (350 mL) at ambient temperature to give an
amber solution. After 2 hours of stirring, toluene (250 mL) was
added, and the ether and THF were removed by distillation.
Triethylamine (60.6 mL) and paraformaldehyde (21.8 g) were then
added as a white slurry in toluene. The reaction was stirred
overnight, followed by heating for 2 hours at 95.degree. C. to give
a cloudy orange solution. The resulting reaction mixture was poured
into 1 M HCl while cooling to 0.degree. C. The organic layer was
separated and the aqueous phase extracted with diethyl ether. The
combined organic phases were dried over Na.sub.2SO.sub.4, and then
evaporated to give an oily orange material. The oil was dissolved
in ethanol (250 mL) and to the clear orange solution was added
cyclohexylamine (32.9 mL). The reaction was stirred for 48 hours
giving a dark orange solution. The solution was cooled in a freezer
causing a yellow crystalline solid to separate. The product was
isolated by filtration and washed with cold ethanol. The imine
product (54 mmol) was dissolved in THF (200 mL) and added dropwise
to a stirring suspension of excess NaH (70 mmol) in THF (250 mL).
The yellow suspension was stirred for 48 hours, the excess NaH
removed by filtration and the solvent removed to give a bright
yellow solid. The sodium salt (46 mmol) was dissolved in THF (150
mL) and added to a suspension of ZrCl.sub.4.THF.sub.2 (23 mmol) in
THF (150 mL). The resulting yellow suspension was stirred for 48
hours. The solvent was removed giving impure product as a very
sparingly soluble yellow residue. The crude material was extracted
with several portions of CH.sub.2Cl.sub.2 followed by solvent
removal to give a yellow solid which was washed with cold
CH.sub.2Cl.sub.2/ether to remove unreacted ligand.
Synthesis of (tBu.sub.3PN)(n-Butyl Indenyl)TiCl.sub.2
[0151] N-BuLi (173 mmol) was added to indene (173 mmol) in THF (70
mL) at ambient temperature using an oil bath as a heat sink. The
reaction was stirred for 40 minutes, then added to n-butyl bromide
(223 mmol) in THF (70 mL) at 0.degree. C. The reaction was stirred
overnight at ambient temperature, followed by standard aqueous
workup. Evaporation of solvent followed by distillation under
reduced pressure gave pure n-butylindene. n-BuLi (13.5 mmol) was
added to n-butylindene (13.5 mmol) in THF (50 mL) and stirred for 1
hour. The solution was then added to ((tBu).sub.3PN)TiCl.sub.3
(which was prepared by the reaction of TiCl.sub.4 with
(tBu).sub.3PN-TMS) slurried in toluene at -78.degree. C. After
stirring overnight at ambient temperature and the solvent was
removed under vacuum. The residue was extracted into toluene,
filtered and the filtrate concentrated. Addition of heptane
precipitated the product that was isolated by filtration.
Synthesis of (tBu.sub.3PN)(C.sub.6F.sub.5CH.sub.2Cp)TiCl.sub.2
[0152] N-BuLi (60 mmol) was added to a solution of
trimethylsilylcyclopentadiene, TMS-C.sub.5H.sub.5 (60 mmol) in THF
(40 mL). After 30 minutes, the solution was added to
pentafluorobenzylbromide (60 mmol) in THF at -45.degree. C. The
reaction was stirred for 2 hours and the solvent removed under
vacuum. The crude residue was distilled under reduced pressure
until it was mostly free of unreacted TMSCpH. The
(TMS)(C.sub.6F.sub.5CH.sub.2)C.sub.5H.sub.4 (22.8 mmol) was added
to TiCl.sub.4 (27 mmol) dropwise over a period of 30 minutes.
Toluene was added to ensure continued stirring. Repeated
trituration with heptane gave the desired product as a solid that
could be isolated by filtration.
Synthesis of (tBu.sub.3PN)(n-BuCpC.sub.6F.sub.5)TiCl.sub.2
[0153] Sodium cyclopentadiene (615 mmol) was dissolved in
tetrahydrofuran and a solution of perfluorobenzene (309 mmol) was
added as a 1:1 solution with THF over a 20 minute period. The
resulting mixture was for 3 hours at 60.degree. C., allowed to
cool, then added by cannula transfer to neat chlorotrimethylsilane
(60 mL) at 0.degree. C. over 15 minutes. The reaction was allowed
to warm to ambient temperature for 30 minutes, followed by slow
concentration over a 3 hour period to remove excess
chlorotrimethylsilane and solvents. The resulting wet solid was
slurried in heptane and filtered. Concentration of the heptane
filtrate gave crude (TMS)(C.sub.6F.sub.5)C.sub.5H.sub.4 as a brown
oil which was used without further purification.
(TMS)(C.sub.6F.sub.5)C.sub.5H.sub.4 (50 mmol) was dissolved in THF
and cooled to 0.degree. C. The solution was treated with n-BuLi (50
mmol), which was added dropwise. After stirring for 10 minutes at
0.degree. C., the reaction was allowed to warm to ambient
temperature and stirred for a further 1 hour. A cold solution of
n-butyl bromide (50 mmol) was prepared in THF (35 mL), and to this
was added the [(TMS)(C.sub.6F.sub.5)C.sub.5H.sub.3]Li solution. The
resulting mixture was stirred for 2 hours and the THF was removed
by evaporation under vacuum. The residue was extracted into heptane
(150 mL), filtered and the solvent was evaporated. TiCl.sub.4 (60
mmol) was added to the (n-Bu)(TMS)(C.sub.6F.sub.5)C.sub.5H.sub.3
via pipette and the solution was heated to 60.degree. C. for 3
hours. Removal of excess TiCl.sub.4 under vacuum gave a thick oil.
Addition of pentane caused immediate precipitation of product
((nBu)(C.sub.6F.sub.5) C.sub.5H.sub.3)TiCl.sub.3 which was isolated
by filtration. ((nBu)(C.sub.6F.sub.5)C.sub.5H.sub.3)TiCl.sub.3
(15.6 mmol) was mixed with (tBu).sub.3PN-TMS (15.6 mmol) in toluene
and stirred overnight at ambient temperature. The solution was
filtered and the solvent removed to give desired product.
Preparation of Silica-Supported Aluminoxane (MAO)
[0154] Sylopol XPO-2408 silica purchased from Grace Davison was
calcined by fluidizing with air at 200.degree. C. for 2 hours and
subsequently with nitrogen at 600.degree. C. for 6 hours. 44.6
grams of the calcined silica was added in 100 mL of toluene. 150.7
g of a MAO solution containing 4.5 weight % Al purchased from
Albemarle was added to the silica slurry. The mixture was stirred
for 1 hour at ambient temperature. The solvent was removed by
vacuum, yielding a free flowing solid containing 11.5 weight %
Al.
Example 1
Preparation of Catalyst A
[0155] In a glovebox, 1.95 g of silica-supported MAO prepared above
was slurried in 15 mL of toluene. Separately, 35 mg of catalyst
component 1 was dissolved in 20 mL of toluene, and 12 mg of
(tBu.sub.3PN)(n-butyl indenyl)TiCl.sub.2 was dissolved in 20 mL of
toluene. Both catalyst solutions were added simultaneously to the
silica slurry. After 1 hour of stirring, the slurry was filtered,
yielding a clear filtrate. The solid component was washed twice
with toluene, and once with heptane. The final product was dried in
vacuo to 300 mtorr (40 Pa) and stored under nitrogen until use.
Polymerization
[0156] A 2 L stirred autoclave reactor was heated at 100.degree. C.
for 1 hour and thoroughly purged with nitrogen. 160 g of NaCl
predried in an oven at 160.degree. C. for at least a week was added
in the reactor which was subsequently pressure purged three times
with nitrogen and twice with ethylene at 100.degree. C. The reactor
was then cooled to 90.degree. C. and an aliquot of 25 weight %
triisobutyl aluminum (TiBAL) was added. The amount of TiBAL was
such that the molar ratio of TiBAL to the total transition metal in
the catalyst to be added was around 500:1. 2 mL of purified
1-hexene was then added and the reactor was pressurized with 100
psig of ethylene. 200 psig of ethylene was used to push 19.2 mg of
Catalyst A from a catalyst tubing into the reactor to start the
reaction. During the polymerization, the reactor pressure was
maintained constant with 200 psig of ethylene and 1-hexene was
continuously fed into the reactor as 10 weight % of ethylene
feeding rate using a mass flow controller. The polymerization was
carried out at 90.degree. C. for 1 hour, yielding 20.0 g of
polymer.
[0157] FIG. 1 shows the GPC-FTIR plot of the polymer. The profile
shows a clear bimodality with most of the comonomer incorporation
being in the high molecular weight fraction.
Example 2
Preparation of Catalyst B
[0158] In a glovebox, 1.95 grams of silica-supported MAO prepared
above was slurried in 15 mL of toluene. Separately, 26 mg of
catalyst component 1 was dissolved in 20 mL of toluene, and 21 mg
of (tBu.sub.3PN)(C.sub.6F.sub.5CH.sub.2Cp)TiCl.sub.2 was dissolved
in 20 mL of toluene. Both catalyst solutions were added
simultaneously to the silica slurry. After one hour of stirring,
the slurry was filtered, yielding a clear filtrate. The solid
component was washed twice with toluene, and once with heptane. The
final product was dried in vacuo to 300 mTorr and stored under
nitrogen until use.
Polymerization
[0159] The polymerization was the same as Example 1, except that
26.7 mg of Catalyst B was used for polymerization, producing 46.8 g
of polymer.
[0160] As seen in FIG. 2, the GPC-FTIR plot shows that the polymer
is bimodal with most of comonomer incorporation in the high
molecular weight fraction.
Example 3
Preparation of Catalyst C
[0161] In a glovebox, 2.92 grams of silica-supported MAO prepared
above was slurried in 30 mL of toluene. Separately, 63.0 mg of
catalyst component 1 was dissolved in 25 mL of toluene, and 13.3 mg
of (tBU.sub.3PN)(C.sub.6F.sub.5)(n-Bu)CpTiCl.sub.2 was dissolved in
10 mL of toluene. Both catalyst solutions were added simultaneously
to the silica slurry. After one hour of stirring, the slurry was
filtered, yielding a clear filtrate. The solid component was washed
twice with toluene, and once with heptane. The final product was
dried in vacuo to 300 mTorr (40 10.sup.2 Pa) and stored under
nitrogen until use.
Polymerization
[0162] The polymerization was the same as Example 1, except that
20.9 mg of Catalyst C was used for polymerization, producing 45.8 g
of polymer
Example 4
Preparation of Catalyst D
[0163] Catalyst D was prepared in the same manner as Catalyst C,
except that the molar ratio of catalyst component 1 to
(tBu.sub.3PN)(C.sub.6F.sub.5)(n-Bu)CpTiCl.sub.2 was 1:1 M/M. The
loading of catalyst components on silica was 0.0355 mmol/g of
catalyst.
Polymerization
[0164] The polymerization was the same as Example 3, except that
19.6 mg of Catalyst D was used for polymerization, producing 17.8 g
of polymer.
Example 5
Preparation of Catalyst E
[0165] Catalyst E was prepared in the same manner as Catalyst C,
except that the molar ratio of catalyst component 1 to
(tBu.sub.3PN)(C.sub.6F.sub.5)(n-Bu)CpTiCl.sub.2 was 1:2 M/M. The
loading of catalyst components on silica 355 mmol/g of
catalyst.
Polymerization
[0166] The polymerization was the same as Example 3, except that
20.7 mg of Catalyst E was used for polymerization, producing 38.0 g
of polymer.
[0167] The GPC-FTIR profiles of the resins produced in Examples 3-5
are shown in FIGS. 3-5, respectively. In all of these examples,
bimodal resins with high comonomer contents in the high molecular
fraction are produced. As the molar ratio of
(tBu.sub.3PN)(C.sub.6F.sub.5CH.sub.2Cp)TiCl.sub.2 to catalyst
component 1 increases (from Example 3 to 5), the ratio of the high
MW fraction to the low MW fraction increases and the Mw of the
bimodal resins also increases steadily (Table 1). This implies that
the composition of the bimodal resins is readily controlled by the
ratio of the two catalyst components in the supported catalyst.
TABLE-US-00001 TABLE 1 Effect of Component Ratio on Supported
(tBu.sub.3PN)(C.sub.6F.sub.5)(n- Bu)CpTiCl.sub.2/Catalyst Component
1 (tBu.sub.3PN)(C.sub.6F.sub.5)(n- Bu)CpTiCl.sub.2/Catalyst
Component 1 Productivity Mn Mw Example (M/M) (g/g) (.times.
10.sup.3) (.times. 10.sup.3) 3 1:4 2,191 9.38 97.5 4 1:2 908 10.90
127.4 5 1:1 1,836 15.80 192.4
* * * * *