U.S. patent application number 11/016104 was filed with the patent office on 2006-06-22 for soluble magnesium complexes useful for the production of polyolefin catalysts and catalysts prepared therewith.
This patent application is currently assigned to Fina Technology, Inc.. Invention is credited to Tim J. Coffy, Steven D. Gray.
Application Number | 20060135354 11/016104 |
Document ID | / |
Family ID | 36588421 |
Filed Date | 2006-06-22 |
United States Patent
Application |
20060135354 |
Kind Code |
A1 |
Coffy; Tim J. ; et
al. |
June 22, 2006 |
SOLUBLE MAGNESIUM COMPLEXES USEFUL FOR THE PRODUCTION OF POLYOLEFIN
CATALYSTS AND CATALYSTS PREPARED THEREWITH
Abstract
A method of forming a polyolefin catalyst component includes
halogenating metal complexes. The metal complexes result from
reacting a metal alkoxide with an alcohol-ether. A particular
non-limiting example is a magnesium complex formed by reacting
magnesium alkoxide with an ethylene alcohol-ether, and then
chlorinating the magnesium complex. Catalyst components, catalysts,
catalyst systems, polyolefin polymers and methods of making each
are disclosed.
Inventors: |
Coffy; Tim J.; (Houston,
TX) ; Gray; Steven D.; (Houston, TX) |
Correspondence
Address: |
FINA TECHNOLOGY INC
PO BOX 674412
HOUSTON
TX
77267-4412
US
|
Assignee: |
Fina Technology, Inc.
Houston
TX
|
Family ID: |
36588421 |
Appl. No.: |
11/016104 |
Filed: |
December 17, 2004 |
Current U.S.
Class: |
502/150 ;
502/103; 502/104; 502/117; 526/119 |
Current CPC
Class: |
C07C 43/13 20130101;
C08F 10/00 20130101; C07C 41/18 20130101; C08F 10/00 20130101; C07C
43/13 20130101; C08F 4/6555 20130101; C08F 4/651 20130101; C08F
4/6548 20130101; C08F 10/00 20130101; C08F 10/00 20130101; C07F
3/003 20130101; C07C 41/18 20130101 |
Class at
Publication: |
502/150 ;
502/103; 502/104; 502/117; 526/119 |
International
Class: |
C08F 4/44 20060101
C08F004/44; B01J 31/00 20060101 B01J031/00 |
Claims
1. A process for making a catalyst precursor comprising contacting
a metal compound of the formula M(OR).sub.2 with alcohol-ethers of
the formula HOCR.sup.1R.sup.2CR.sup.3R.sup.4OR.sup.5 to form a
three- or four-coordinate catalyst precursor having the general
formula: ##STR7## where M is a metal from Group IIA of the Periodic
Table, n=1 or 2, R is a hydrocarbyl having from 1 to 20 carbon
atoms; R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are the same
or different; and R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5
are a substituted or unsubstituted alkyl or aryl moiety having from
about 1 to about 20 carbons atoms or hydrogen.
2. The process of claim 1 wherein M is magnesium, and wherein R is
ethyl.
3. The process of claim 1 wherein the alcohol-ether is ethylene
glycol monopropyl ether.
4. The process of claim 1 further comprising contacting the
catalyst precursor with an organometallic agent.
5. The process of claim 1 further comprising contacting the
catalyst precursor with a first halogenating and/or
halogenating/titanating agent to form a halogenated catalyst
precursor.
6. The process of claim 5 further comprising contacting the
halogenated catalyst precursor with a second halogenating and/or
halogenating/titanating agent.
7. The process of claim 1 further comprising contacting the
catalyst precursor with a titanating agent to form a catalyst.
8. The process of claim 7 further comprising contacting the
catalyst with a halogenating agent.
9. The process of claim 5 wherein the first halogenating and/or
halogenating/titanating agent is a mixture of Ti(OBu).sub.4 and
TiCl.sub.4.
10. The process of claim 6 wherein the second halogenating and/or
halogenating/titanating agent is TiCl.sub.4.
11. The process of claim 4 wherein the organometallic agent
comprises an organo-aluminum compound.
12. The process of claim 4 further comprising adding at least one
internal electron donor.
13. The process of claim 4 further comprising precipitating the
catalyst with a support template.
14. A process for olefin polymerization, the process comprising
contacting one or more olefin monomers together in the presence of
a catalyst under polymerization conditions, wherein the catalyst is
produced by a process comprising contacting a metal compound of the
formula M(OR).sub.2 with alcohol-ethers of the formula
HOCR.sup.1R.sup.2CR.sup.1R.sup.4OR.sup.5 to form a three- or
four-coordinate catalyst precursor having the general formula:
##STR8## where M is a metal from Group IIA of the Periodic Table,
n=1 or 2, R is a hydrocarbyl having from 1 to 20 carbon atoms;
R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are the same or
different; and R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are a
substituted or unsubstituted alkyl or aryl moiety having from about
1 to about 20 carbons atoms or hydrogen.
15. The process of claim 14 further comprising extracting
polyolefin polymers.
16. A catalyst produced by a process comprising contacting a metal
compound of the formula M(OR).sub.2 with alcohol-ethers of the
formula HOCR.sup.1R.sup.2CR.sup.3R.sup.4OR.sup.5 to form a three-
or four-coordinate catalyst precursor having the general formula
##STR9## where M is a metal from Group IIA of the Periodic Table,
n=1 or 2, R is a hydrocarbyl having from 1 to 20 carbon atoms;
R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are the same or
different; and R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are a
substituted or unsubstituted alkyl or aryl moiety having from about
1 to about 20 carbons atoms or hydrogen.
17. The catalyst of claim 16 wherein M is magnesium, and wherein R
is ethyl.
18. The catalyst of claim 16 where the alcohol-ether is is ethylene
glycol monopropyl ether.
19. The catalyst of claim 16 wherein the catalyst precursor is
contacted with an organometallic agent.
20. The catalyst of claim 16 wherein the catalyst precursor is
contacted with a first halogenating and/or halogenating/titanating
agent to form a halogenated catalyst precursor.
21. The catalyst of claim 20 wherein the halogenated catalyst
precursor is contacted with a second halogenating and/or
halogenating/titanating agent.
22. The catalyst of claim 16 wherein the catalyst precursor is
contacted with a titanating agent to form a catalyst component.
23. The catalyst of claim 22 wherein the catalyst component is
contacted with a halogenating agent.
24. The catalyst of claim 20 wherein the first halogenating and/or
halogenating/titanating agent is a mixture of Ti(OBu).sub.4 and
TiCl.sub.4.
25. The catalyst of claim 21 wherein the second halogenating and/or
halogenating/titanating agent is TiCl.sub.4.
26. The catalyst of claim 16 wherein the process further comprises
the addition of an internal electron donor.
27. The catalyst of claim 17 wherein the process further comprises
precipitating the catalyst in the presence of a support
template.
28. A polymer produced by a process comprising contacting one or
more olefin monomers in the presence of a catalyst, the catalyst
being produced by a process comprising contacting a metal compound
of the formula M(OR).sub.2 with alcohol-ethers of the formula
HOCR.sup.1R.sup.2CR.sup.3R.sup.4OR.sup.5 to form a three- or
four-coordinate catalyst precursor having the general formula:
##STR10## where M is a metal from Group IIA of the Periodic Table,
n=1 or 2, R is a hydrocarbyl having from 1 to 20 carbon atoms;
R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are the same or
different; and R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are a
substituted or unsubstituted alkyl or aryl moiety having from about
1 to about 20 carbons atoms or hydrogen.
29. The polymer of claim 28 wherein M is magnesium, and wherein R
is ethyl.
30. The polymer of claim 28 where the alcohol-ether is is ethylene
glycol monopropyl ether.
31. The polymer of claim 28 wherein the catalyst precursor is
contacted with an organometallic agent.
32. The polymer of claim 28 wherein the catalyst precursor is
contacted with a first halogenating and/or halogenating/titanating
agent to form a halogenated catalyst precursor.
33. The polymer of claim 32 wherein the halogenated catalyst
precursor is contacted with a second halogenating and/or
halogenating/titanating agent.
34. The polymer of claim 28 wherein the catalyst precursor is
contacted with a titanating agent to form a catalyst component.
35. The polymer of claim 34 wherein the catalyst component is
contacted with a halogenating agent.
36. The polymer of claim 32 wherein the first halogenating and/or
halogenating/titanating agent is a mixture of Ti(OBu).sub.4 and
TiCl.sub.4.
37. The polymer of claim 33 wherein the second halogenating and/or
halogenating/titanating agent is TiCl.sub.4.
38. The polymer of claim 28 wherein the process further comprises
the addition of an internal electron donor.
39. The polymer of claim 28 wherein the process further comprises
precipitating the catalyst in the presence of a support
template.
40. An article of manufacture comprising an article comprising a
polymer of claim 28 wherein the polymer is converted into a film
and the article is a food wrapper; the polymer is converted by blow
molding and the blown molded article is a milk bottle, bleach
bottle or a toy part; or the polymer is converted into pipe and the
article is a PE-100 pressure-rated pipe.
Description
FIELD OF THE INVENTION
[0001] The invention relates to catalysts, methods of making
catalysts, and processes for polymerizing olefins, and relates more
particularly to polyolefin catalysts, methods of making polyolefin
catalysts, and methods of polymerizing olefins.
BACKGROUND OF THE INVENTION
[0002] Olefins, also called alkenes, are unsaturated hydrocarbons
whose molecules contain one or more pairs of carbon atoms linked
together by a double bond. When subjected to a polymerization
process, olefins are converted to polyolefins, such as polyethylene
and polypropylene. Ziegler-type polyolefin catalysts, their general
methods of making, and subsequent use, are known in the
polymerization art. While much is known about Ziegler-type
catalysts, there is a constant search for improvements in their
polymer yield, catalyst life, catalyst activity, amenability to use
in large scale production processes, and in their ability to
produce polyolefins having certain properties.
[0003] Conventional Ziegler-Natta catalysts comprise a transition
metal compound generally represented by the formula: MR.sup.+.sub.x
where M is a transition metal, R.sup.+ is a halogen or a
hydrocarboxyl, and x is the valence of the transition metal.
Typically, M is a group IVB metal such as titanium, chromium, or
vanadium, and R.sup.+ is chlorine, bromine, or an alkoxy group. The
transition metal compound is typically supported on an inert solid,
e.g., magnesium chloride.
[0004] The properties of the polymerization catalyst may affect the
properties of the polymer formed using the catalyst. For example,
polymer morphology typically depends upon catalyst morphology.
Acceptable polymer morphology differs for each class of production
process (e.g., slurry loop, bimodal, gas phase, etc.), but
typically includes uniformity of particle size and shape and an
acceptable bulk density. Furthermore, there is a need in the art of
preparing polymers to minimize the number of very small polymer
particles (i.e., fines) to avoid plugging polymer transfer lines or
solvent recovery systems.
SUMMARY OF THE INVENTION
[0005] In one aspect, the invention is a process for making a
catalyst precursor that involves contacting a metal compound of the
formula M(OR).sub.2 with alcohol-ethers of the formula
HOCR.sup.1R.sup.2CR.sup.3R.sup.4OR.sup.5 to form a three- or
four-coordinate catalyst precursor having the general formula:
##STR1## where M is a metal from Group IIA of the Periodic Table,
n=1 or 2, R is a hydrocarbyl having from 1 to 20 carbon atoms;
R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are the same or
different; and R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are a
substituted or unsubstituted alkyl or aryl moiety having from about
1 to about 20 carbons atoms or hydrogen. In one specific,
non-limiting embodiment of the invention M is magnesium and R is
ethyl.
[0006] In another aspect, the invention is a process for olefin
polymerization, the process including contacting one or more olefin
monomers together in the presence of a catalyst under
polymerization conditions, wherein the catalyst is produced by a
process including contacting a metal compound of the formula
M(OR).sub.2 with alcohol-ethers of the formula
HOCR.sup.1R.sup.2CR.sup.3R.sup.4OR.sup.5 to form a three- or
four-coordinate catalyst precursor having the general formula:
##STR2## where M is a metal from Group IIA of the Periodic Table,
n=1 or 2, R is a hydrocarbyl having from 1 to 20 carbon atoms;
R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are the same or
different; and R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are a
substituted or unsubstituted alkyl or aryl moiety having from about
1 to about 20 carbons atoms or hydrogen.
[0007] Another aspect of the invention is a catalyst produced by a
process contacting a metal compound of the formula M(OR).sub.2 with
alcohol-ethers of the formula
HOCR.sup.1R.sup.2CR.sup.3R.sup.4OR.sup.5 to form a three- or
four-coordinate catalyst precursor having the general formula:
##STR3## where M is a metal from Group IIA of the Periodic Table,
n=1 or 2, R is a hydrocarbyl having from 1 to 20 carbon atoms;
R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are the same or
different; and R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are a
substituted or unsubstituted alkyl or aryl moiety having from about
1 to about 20 carbons atoms or hydrogen.
[0008] An aspect of the invention is a polymer produced by a
process including contacting one or more olefin monomers in the
presence of a catalyst, the catalyst being produced by a process
including contacting a metal compound of the formula M(OR).sub.2
with alcohol-ethers of the formula
HOCR.sup.1R.sup.2CR.sup.3R.sup.4OR.sup.5 to form a three- or
four-coordinate catalyst precursor having the general formula
##STR4## where M is a metal from Group IIA of the Periodic Table,
n=1 or 2, R is a hydrocarbyl having from 1 to 20 carbon atoms;
R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are the same or
different; and R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are a
substituted or unsubstituted alkyl or aryl moiety having from about
1 to about 20 carbons atoms or hydrogen.
[0009] In still another aspect, the invention is an article of
manufacture including an article prepared using a polymer produced
by a process including contacting one or more olefin monomers in
the presence of a catalyst, the catalyst being produced by a
process including contacting a metal compound of the formula
M(OR).sub.2 with alcohol-ethers of the formula
HOCR.sup.1R.sup.2CR.sup.3R.sup.4OR.sup.5 to form a three- or
four-coordinate catalyst precursor having the general formula:
##STR5## where M is a metal from Group IIA of the Periodic Table,
n=1 or 2, R is a hydrocarbyl having from 1 to 20 carbon atoms;
R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are the same or
different; and R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are a
substituted or unsubstituted alkyl or aryl moiety having from about
1 to about 20 carbons atoms or hydrogen. The polymer may be formed
into a film and employed in food packaging; the polymer may be
formed by blow molding and the blown molded article may be a milk
bottle, bleach bottle or a toy part; or the polymer may be formed
into pipe and the article is a PE 100 pressure-rated pipe.
DETAILED DESCRIPTION OF THE INVENTION
[0010] One commonly used polymerization process involves contacting
an olefin monomer with a catalyst system that includes a
conventional Ziegler-Natta catalyst, a co-catalyst, and one or more
electron donors. Examples of such catalyst systems are provided in
U.S. Pat. Nos. 4,107,413; 4,294,721; 4,439,540; 4,114,319;
4,220,554; 4,460,701; 4,562,173; and 5,066,738, which are
incorporated herein by reference.
[0011] The invention relates to the production of novel, three or
four coordinate, metal complexes as precursors for Ziegler-Natta
catalysts, in one non-restrictive version magnesium catalysts. The
discovery of new magnesium complexes with high solubility in
hydrocarbon solvents is important to the development of
Ziegler-Natta catalysts and was not predicted.
[0012] It has been surprisingly and unexpectedly discovered that
magnesium complexes of the general class,
Mg(OCH.sub.2CH.sub.2OR).sub.2 are readily generated in situ by the
reaction of Mg(OEt).sub.2 and ethylene alcohol-ethers as shown
below:
Mg(OEt).sub.2+2HOCH.sub.2CH.sub.2OR'.fwdarw.Mg(OCH.sub.2CH.sub.2OR').sub.-
2+2EtOH These above-mentioned complexes are soluble in hydrocarbon
solvents such as heptane and toluene. The central metal or
magnesium core in these complexes can be be four coordinate. In an
alternative embodiment, one equivalent of the ethylene
alcohol-ether can be used to produce a 3 coordinate catalyst
precursor. The steric bulk afforded by these ligands allows their
conversion to magnesium chloride-supported Ziegler-Natta catalysts
by treatment with titanium chlorides of the general class
Ti(OR).sub.nCl.sub.4-z (where z=0-4) to occur in a very controlled
fashion. This feature is important to the development of catalysts
capable of providing polyolefins with a controlled morphology.
[0013] The catalyst precursor components of the invention have the
general type of formula: ##STR6##
[0014] where M is a metal from Group IIA of the Periodic Table, n=1
or 2, R is a hydrocarbyl having from 1 to 20 carbon atoms; R.sup.1,
R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are the same or different;
and R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are a
substituted or unsubstituted alkyl or aryl moiety having from about
1 to about 20 carbons atoms or hydrogen. Substituted alkyl radicals
such as --CF.sub.3, --CCl.sub.3, and the like; radicals including
Si and silicon ethers such as --O--SiO.sub.2; and aryl radicals
such as a nitrobenzyl radical and an anisole radical may be
used.
[0015] Suitable metal alkoxides may generally be described as
having two alkoxide groups. The alkoxide groups may each be
independently selected from among unsubstituted and substituted
alkoxides having alkyl groups in the range of 1 to 10 carbons
atoms. In one embodiment, the alkoxide groups have 1 to 4 carbon
atoms, such as 2 to about 4 carbons atoms. Non-limiting examples of
metal alkoxides suitable for use include magnesium alkoxides such
as, for example, magnesium ethoxide.
[0016] A wide variety of alcohol-ethers are available both
commercially and via the treatment of epoxides with alcohols and
amines which afford the opportunity to "fine tune" both the steric
and the electronic properties of the magnesium complex. Specific
examples of suitable alcohol-ethers include, but are not
necessarily limited to: ethylene glycol monopropyl ether, ethylene
glycol monoethyl ether, ethylene glycol monobutyl ether, propylene
glycol monomethyl ether, and the like.
[0017] In the invention, suitable metal alkoxides may generally be
described as having two alkoxide groups. The alkoxide groups can
each be independently selected from among unsubstituted and
substituted alkoxides having alkyl groups in the range of 1 to 10
carbons atoms. In another non-limiting embodiment of the invention,
the alkoxide groups have 1 to 4 carbon atoms, such as 2 to about 4
carbons atoms. Non-limiting examples of metal alkoxides suitable
for use in the invention include, but are not necessarily limited
to, magnesium alkoxides such as, for example, magnesium
ethoxide.
[0018] In the practice of forming the catalyst components of the
invention, the metal alkoxide is generally contacted with the
alkylene alcohol-ether at conditions suitable to yield the desired
metal catalyst precursor complex. Suitable temperatures for the
contacting of the metal alkoxide with the alkylene alcohol-ether
are generally in the range of about -20.degree. C. to about
100.degree. C., desirably in the range of about 0.degree. C. to
about 50.degree. C., and may be in the range of about 0.degree. C.
to about 25.degree. C. The slurry may be heated to facilitate
displacement substitution of the OR group with the alkylene
alcohol-ether. In the practice of the invention, the metal alkoxide
and alkylene alcohol-ether may be contacted together in any
suitable solvent or reaction medium. Non-limiting examples of
suitable solvents or reaction media include toluene, heptane,
hexane, octane and the like.
[0019] The catalyst precursor may be further modified by contacting
the precursor with an organometallic agent. Suitable organometallic
agents include but are not limited to aluminum alkyls, aluminum
alkyl hydrides, lithium aluminum alkyls, zinc alkyls, magnesium
alkyls and the like. Contacting the precursor with the
organometallic agents may reduce solution viscosity and may also
reduce byproducts such as alcohols.
[0020] The catalyst precursor may be halogenated to form a catalyst
support. It may also be titanated or titanated and halogenated to
form a supported catalyst. Agents useful for halogenating the metal
bis(alkylene alcohol-ether) include any halogenating agent which,
when utilized in the invention, will yield a suitable catalyst.
Some of the halogenating agents may also serve as titanating agents
useful for incorporating titanium into the catalyst precursor which
is necessary to impart catalytic properties to the catalysts
precursor. For example, TiCl.sub.4 may both titanate and halogenate
a catalyst precursor.
[0021] Metal chlorides may be desirable halogenating agents and/or
titanating/halogenating agents. Non-limiting examples of suitable
halogenating and/or titanating/halogenating agents include Group
III, Group IV and Group V halides, hydrogen halides, or the
halogens themselves. Specific examples of halogenating and/or
titanating/halogenating agents are BCl.sub.3, AlCl.sub.3,
CCl.sub.4, SiCl.sub.4, TiCl.sub.4, ZrCl.sub.4, VOCl.sub.4,
VOCl.sub.2, CrOCl.sub.2, SbCl.sub.5, POCl.sub.2, PCl.sub.5,
HfCl.sub.4, and Ti(OR).sub.nCl.sub.4-n, wherein R is an alkyl
having 1 to 8 carbon atoms, and n is from 0 to 4. Mixtures of any
of two or more of the foregoing may also be used as halogenating
and/or titanating/halogenating agents. Other halogenating and/or
titanating/halogenating agents include alkyl halo silanes of the
formula R'.sub.nSiX.sub.(4-n), wherein X is a halogen, R' is a
substituted or unsubstituted hydrocarbyl having 1 to 20 carbon
atoms, and n is 1-3
[0022] Possible halogenating and/or titanating/halogenating agents
are SiCl.sub.4, TiCl.sub.4, TiCl.sub.n(OR).sub.4-n, and mixtures of
any of two or more of the foregoing. One embodiment employs as the
halogenating agent a mixture of TiCl.sub.4, and Ti(OR).sub.4,
wherein R is a butyl group. The molar ratio of TiCl.sub.4 to
Ti(OR).sub.n is generally in the range of about 4 to about 0.1, may
be in the range of about 3 to about 1, and may be in the narrower
range of about 2 to about 1.
[0023] In the practice of the invention, there is generally at
least one halogenation step, and there may be two or more. A
non-limiting example of a suitable halogenation treatment includes
a first halogenation treatment with a mixture of TiCl.sub.4 and
Ti(OR).sub.4, followed by a second halogenation treatment with
TiCl.sub.4. Halogenation and titanation of catalysts and catalyst
precursors is disclosed in U.S. Pat. No. 6,693,058 to Coffy, et
al., the contents of which are incorporated herein by
reference.
[0024] The halogenation and titanation of the metal bis(alkylene
alcohol-ether) may be carried out under conditions suitable to
yield the desired catalyst component. Suitable temperatures for
halogenating and titanating are generally in the range of about
-20.degree. C. to about 100.degree. C., may be in the range of
about 0.degree. C. to about 75.degree. C. and may be in the
narrower range of about 25.degree. C. to about 65.degree. C.
[0025] In the practice of the invention, halogenation may be
conducted at a molar ratio of halogenating agent to metal
bis(alkylene alcohol-ether) generally in the range of about 1 to
about 20, may be in the range of about 1 to about 10, and may be in
the narrower range of about 1 to about 8.
[0026] In the practice of the invention, the halogenating agent and
the metal bis(alkylene alcohol-ether) may be contacted together in
any suitable solvent or reaction medium. Non-limiting examples of
suitable solvents or reaction media include toluene, heptane,
hexane, octane and the like.
[0027] In contrast to conventional practice, in an embodiment of
the invention, a solid product precipitated in the halogenation
and/or titanation step is the desired catalyst or support component
that is then recovered by any suitable recovery technique. This
desired catalyst or support component may then be utilized as a
catalyst for the production of a controlled morphology
Ziegler-Natta-type catalyst. The catalyst can be formed by direct
precipitation of the three- or four-coordinate soluble
intermediate, or it can be precipitated in the presence of a
support template to form a supported catalyst. Silica or magnesium
chloride can be used as a support template.
[0028] An internal electron donor for treating the catalyst or
catalyst precursor may be used. The internal electron donor may be
added during or after the halogenation step. Internal electron
donors for use in the preparation of polyolefin catalysts are
known, and any suitable internal electron donor may be utilized in
the invention that will provide a suitable catalyst. Internal
electron donors, also known as Lewis bases, are organic compounds
of oxygen, nitrogen, phosphorous, or sulfur which are capable of
donating an electron pair to the catalyst. The internal electron
donor may be a monofunctional or polyfunctional compound, and may
be selected from among the aliphatic or aromatic carboxylic acids
and their alkyl esters, the aliphatic or cyclic ethers, ketones,
vinyl esters, acryl derivatives, particularly alkyl acrylates or
methacrylates and silanes. The amount of internal electron donor
utilized may vary over a broad range and is generally in the range
of about 0.01 to about 2 equivalents, but may be in the range of
about 0.05 to about 0.5 equivalents. The catalyst precursor may be
contacted with the internal electron donor for a contacting period
in the range of about 0.5 hours to about 4 hours. In one embodiment
a range of about 1 hour to about 2 hours is employed.
[0029] The catalyst made by the above described process may be
combined with an organo-aluminum cocatalyst component to generate a
catalyst system suitable for the polymerization of olefins.
Typically, the cocatalysts which are used together with the
transition metal containing catalyst are organometallic compounds
of Group Ia, IIa, and IIIa metals such as aluminum alkyls, zinc
alkyls, magnesium alkyls and the like. Organometallic compounds
that may be employed in the practice of the invention are
trialkylaluminum compounds.
[0030] External electron donors that may be added at the end of the
preparation or utilized with the use of catalyst during
polymerization and include those known in the art, including, but
not limited to alkoxysilanes.
[0031] The catalysts described herein may be used for the
polymerization of olefins, including .alpha.-olefins. For example,
the present catalyst is useful for catalyzing ethylene, propylene,
butylene, pentene, hexene, 4-methylpentene and other alkenes having
at least 2 carbon atoms, and also for mixtures thereof. These
catalysts may be utilized for the polymerization of ethylene to
produce polyethylene, such as polyethylene with controlled powder
morphology. Olefin polymerization methods are well known in
general, and any suitable method may be utilized. The catalysts of
the invention may offer improvements in one or more of the
following properties: activity, morphology control, fines
reduction, and hydrogen response.
[0032] In one embodiment, the polymers of the invention are
converted into a film and the film used in food packaging. In
another embodiment, the polymer is converted by blow molding and
the molded article is a milk bottle, bleach bottle or toy part. In
still another embodiment, the polymer is formed into pipe and the
pipe is a PE-100 pressure-rated pipe.
[0033] The following non-limiting example is provided merely to
illustrate the invention, and is not meant to limit the scope of
the claims.
EXAMPLE
[0034] In a drybox a four-necked, one-liter flask is equipped with
a 125 ml addition funnel, a magnetic stir bar, a condenser with a
gas inlet, a thermometer, and a septum. The flask is charged with
Mg(OEt).sub.2 (2.5 g, 22 mmol) and brought to the Schlenk line
where it is placed under a rapid argon purge. Heptane (100 ml) is
added to the flask and the mixture is rapidly stirred.
[0035] A solution of ethylene glycol monopropyl ether (EPH, 4.58 g,
44 mmol) diluted to 100 ml total volume with heptane is added
dropwise to the Mg(OEt).sub.2 slurry. Immediate reaction is seen as
the solution grew cloudy. The solution is next heated to reflux.
Gradually with heating, the solution became slightly yellow in
color and the solid completely dissolved. Upon reaching 78.degree.
C., a component of the solution is seen to reflux. Heating is
continued until the solution temperature reached 90.degree. C. The
mixture is allowed to react at this temperature for 1 hour.
[0036] The solution is cooled to 75.degree. C. and a solution of
TEAl (1.67 g, 14.7 mmol) in heptane (diluted to 50 ml total volume)
is next added dropwise to the slurry. Addition is complete in 45
minutes and the solution is mobile and clear at this time. The
mixture is allowed to stir at 55.degree. C. for 30 minutes.
[0037] After 1 hour, the solution is allowed to cool to room
temperature. No solid formation is seen upon cooling the solution.
The solvent is next removed under reduced pressure to yield
Mg(OCH.sub.2CH.sub.2OCH.sub.2CH.sub.2CH.sub.3).sub.2 as a yellow
gel.
[0038] This complex and others of the class are subjected to
treatment with titanium chlorides of the general class
TiCl.sub.z(OR).sub.4-z (z=0-4) to provide magnesium chloride
supported Ziegler-Natta catalysts for the production of
polyolefins.
[0039] While the illustrative embodiments of the invention have
been described with particularity, it will be understood that
various other modifications will be apparent to, and may be readily
made by, those skilled in the art without departing from the scope
of the invention. Accordingly, it is not intended that the scope of
the claims appended hereto be limited to the examples and
descriptions set forth herein but rather that the claims be
construed as encompassing all the features of patentable novelty
which reside in the invention, including all features which would
be treated as equivalents thereof by those skilled the art to which
this invention pertains.
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