U.S. patent application number 10/236543 was filed with the patent office on 2003-08-07 for ethylene interpolymer blend compositions.
Invention is credited to Cardwell, Robert S., Chaudhary, Bharat I., Kolthammer, Brian W.S., Laubach, Adam E., Markovich, Ronald P., Nieto, Jesus.
Application Number | 20030149181 10/236543 |
Document ID | / |
Family ID | 27359333 |
Filed Date | 2003-08-07 |
United States Patent
Application |
20030149181 |
Kind Code |
A1 |
Kolthammer, Brian W.S. ; et
al. |
August 7, 2003 |
Ethylene interpolymer blend compositions
Abstract
Film, molded articles and fibers prepared from
ethylene/.alpha.-olefin interpolymer compositions are disclosed.
The interpolymer compositions are blends prepared by combining
specified amounts of a narrow molecular weight distribution, narrow
composition distribution breadth index interpolymer, and a broad
molecular weight distribution, broad composition distribution
breadth index interpolymer, with each blend component having a
specified density, melt index and degree of branching.
Inventors: |
Kolthammer, Brian W.S.;
(Lake Jackson, TX) ; Cardwell, Robert S.; (Lake
Jackson, TX) ; Markovich, Ronald P.; (Houston,
TX) ; Chaudhary, Bharat I.; (Pearland, TX) ;
Laubach, Adam E.; (Lake Jackson, TX) ; Nieto,
Jesus; (Cambrils, ES) |
Correspondence
Address: |
WHYTE HIRSCHBOECK DUDEK S.C.
111 E. WISCONSIN AVE, SUITE 2100
MILWAUKEE
WI
53202
US
|
Family ID: |
27359333 |
Appl. No.: |
10/236543 |
Filed: |
September 6, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10236543 |
Sep 6, 2002 |
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09645731 |
Aug 24, 2000 |
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6448341 |
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09645731 |
Aug 24, 2000 |
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09121689 |
Jul 23, 1998 |
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09121689 |
Jul 23, 1998 |
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08747419 |
Nov 12, 1996 |
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5844045 |
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08747419 |
Nov 12, 1996 |
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08010958 |
Jan 29, 1993 |
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Current U.S.
Class: |
525/240 ;
264/310; 264/331.17 |
Current CPC
Class: |
C08F 4/65908 20130101;
C08F 297/08 20130101; C08F 2500/03 20130101; C08F 2500/12 20130101;
C08F 210/14 20130101; C08F 4/6555 20130101; C08L 2666/04 20130101;
C08F 2500/06 20130101; C08F 2/001 20130101; C08F 2500/03 20130101;
C08F 2500/08 20130101; C08F 2500/12 20130101; C08L 23/0815
20130101; C08F 210/14 20130101; C08F 210/16 20130101; C08L 23/0815
20130101; C08F 210/16 20130101; C08L 2205/02 20130101; C08F 210/16
20130101; C08L 2314/06 20130101; C08F 210/16 20130101; C08L 2314/02
20130101; C08L 2314/04 20130101; C08F 4/65912 20130101; C08F 210/16
20130101 |
Class at
Publication: |
525/240 ;
264/310; 264/331.17 |
International
Class: |
C08L 023/08 |
Claims
We claim:
1. A molded article comprising an ethylene/.alpha.-olefin
interpolymer composition comprising; (A) an ethylene/.alpha.-olefin
interpolymer which; (i) has a narrow molecular weight distribution,
defined as an M.sub.w/M.sub.n of less than about 3, (ii) has a
narrow composition distribution breadth index, CDBI, (defined as
the weight percent of the polymer molecules having a comonomer
content within 50 percent of the median total molar comonomer
content of Component A) which is greater than about 50 percent;
(iii) has a degree of branching less than or equal to 2
methyls/1000 carbons in about 15 percent or less by weight (based
on the total weight of Component A); (iv) has an aluminum residue
content of less than or equal to about 250 ppm present in the
interpolymer composition, and (v) is present in an amount of from
about 15 to about 85% by weight (based on the combined weight of
Components A and B); and (B) an ethylene/.alpha.-olefin
interpolymer; which (i) has a broad molecular weight distribution,
defined as an M.sub.w/M.sub.n of greater than about 3, (ii) has a
broad composition distribution with a degree of branching less than
or equal to 2 methyls/1000 carbons in about 10 percent or more by
weight (based on the total weight of Component B),; (iii) has a
degree of branching greater than or equal to 25 methyls/1000
carbons in about 25 percent or less by weight (based on the total
weight of Component B); and (iv) is present in an amount of from
about 15 to about 85% by weight based on the combined weight of
Components A and B; and wherein said molded article is made by
rotational molding, injection molding or blow molding.
2. The molded article of claim 1 wherein said interpolymer
composition has a density of from about 0.870 to about 0.965
g/cm.sup.3 and a melt index (I.sub.2) of from about 0.1 to about
100 g/10 min; and wherein (A) Component A is an interpolymer of
ethylene with at least one C.sub.3-8 .alpha.-olefin and has a
density of from about 0.865 to about 0.920 g/cm.sup.3, and (B)
Component B is an interpolymer of ethylene with at least one
C.sub.3-8 .alpha.-olefin and has a density of from about 0.915 to
about 0.965 g/cm.sup.3.
3. The molded article of claim 1 wherein said interpolymer
composition has a density of from about 0.940 to about 0.960 and a
melt index (I2) of from about 3 to about 100 g/10 min; and wherein
(A) Component A is an interpolymer of ethylene with at least one
C.sub.3-8 .alpha.-olefin and present in an amount of from about 5
to about 50% by weight (based on the combined weight of Components
A and B) and has a density of from about 0.850 to about 0.908
g/cm3; and (B) Component B is one or more homopolymers or
interpolymers of ethylene and/or at least one C.sub.3-8
.alpha.-olefin and is present in an amount of from about 50 to
about 95% by weight (based on the combined weight of Components A
and B); and wherein (C) said interpolymer composition has an
improvement in 23.degree. C. Izod Impact of at least 5% over a
blend of the same final melt index and density, but wherein the
density of Component A is greater than or equal to 0.909
g/cm.sup.3.
4. The molded article of claim 1 wherein said interpolymer
composition has a density of from about 0.940 to about 0.955 and a
melt index (I2) of from about 3 to about 50 g/10 min; and wherein
(A) Component A is an interpolymer of ethylene with at least one
C.sub.3-8 .alpha.-olefin and present in an amount of from about 7
to about 50% by weight (based on the combined weight of Components
A and B) and has a density of from about 0.850 to about 0.906
g/cm3; and (B) Component B is one or more homopolymers or
interpolymers of ethylene and/or at least one C.sub.3-8
.alpha.-olefin and is present in an amount of from about 50 to
about 93% by weight(based on the combined weight of Components A
and B); and wherein said interpolymer composition has an
improvement in 23.degree. C. Izod Impact of at least 7% over a
blend of the same final melt index and density, but wherein the
density of Component A is greater than or equal to 0.909
g/cm.sup.3.
5. The molded article of claim 4 wherein said interpolymer
composition has a density of from about 0.940 to about 0.950 and a
melt index (I2) of from about 3 to about 25 g/10 min; and wherein
(A) Component A is an interpolymer of ethylene with at least one
C.sub.3-8 .alpha.-olefin and present in an amount of from about 10
to about 50% by weight (based on the combined weight of Components
A and B) and has a density of from about 0.850 to about 0.903
g/cm3; and (B) Component B is one or more homopolymers or
interpolymers of ethylene and/or at least one C.sub.3-8
.alpha.-olefin and is present in an amount of from about 50 to
about 90% by weight(based on the combined weight of Components A
and B); and wherein said interpolymer composition has an
improvement in 23.degree. C. Izod Impact of at least 10% over a
blend of the same final melt index and density, but wherein the
density of Component A is greater than or equal to 0.909
g/cm.sup.3.
6. The molded article of claim 1 wherein said interpolymer
composition has a density of from about 0.930 to about 0.965 and a
melt index (I2) of from about 0.5 to about 4 g/10 min; and wherein
(A) Component A is an interpolymer of ethylene with at least one
C.sub.3-8 .alpha.-olefin and present in an amount of from about 10
to about 50% by weight (based on the combined weight of Components
A and B) and has a density of from about 0.850 to about 0.903
g/cm3; and (B) Component B is one or more homopolymers or
interpolymers of ethylene and/or at least one C.sub.3-8
.alpha.-olefin and is present in an amount of from about 50 to
about 90% by weight(based on the combined weight of Components A
and B); and wherein said interpolymer composition has an
improvement in 0.degree. C. Izod Impact of at least 5% over a blend
of the same final melt index and density, but wherein the density
of Component A is greater than or equal to 0.909 g/cm.sup.3.
7. The molded article of claim 1 wherein said interpolymer
composition has a density of from about 0.935 to about 0.945 and a
melt index (I2) of from about 0.5 to about 3.3 g/10 min; and
wherein (A) Component A is an interpolymer of ethylene with at
least one C.sub.3-8 .alpha.-olefin and present in an amount of from
about 15 to about 50% by weight (based on the combined weight of
Components A and B) and has a density of from about 0.850 to about
0.890 g/cm3; and (B) Component B is one or more homopolymers or
interpolymers of ethylene and/or at least one C.sub.3-8
.alpha.-olefin and is present in an amount of from about 50 to
about 85% by weight(based on the combined weight of Components A
and B); and wherein said interpolymer composition has an
improvement in -20.degree. C. Izod Impact of at least 5% over a
blend of the same final melt index and density, but wherein the
density of Component A is greater than or equal to 0.909
g/cm.sup.3.
8. A film made from an ethylene/.alpha.-olefin interpolymer
composition comprising; (A) an ethylene/.alpha.-olefin interpolymer
which; (i) has a narrow molecular weight distribution, defined as
an M.sub.w/M.sub.n of less than about 3, (ii) has a narrow
composition distribution breadth index, CDBI, (defined as the
weight percent of the polymer molecules having a comonomer content
within 50 percent of the median total molar comonomer content of
Component A) which is greater than about 50 percent; (iii) has a
degree of branching less than or equal to 2 methyls/1000 carbons in
about 15 percent or less by weight (based on the total weight of
Component A); (iv) has an aluminum residue content of less than or
equal to about 250 ppm present in the interpolymer composition, and
(v) is present in an amount of from about 15 to about 85% by weight
(based on the combined weight of Components A and B); and (B) an
ethylene/.alpha.-olefin interpolymer; which (i) has a broad
molecular weight distribution, defined as defined as an
M.sub.w/M.sub.n of greater than about 3, (ii) has a broad
composition distribution with a degree of branching less than or
equal to 2 methyls/1000 carbons in about 10 percent or more by
weight (based on the total weight of Component B); (iii) has a
degree of branching greater than or equal to 25 methyls/1000
carbons in about 25 percent or less by weight (based on the total
weight of Component B); and (iv) is present in an amount of from
about 15 to about 85% by weight based on the combined weight of
Components A and B; and wherein said film is a cast film or a blown
film or an extrusion coated film.
9. A cast film of claim 8, said interpolymer composition having a
density of from about 0.870 to about 0.965 g/cm.sup.3; a melt index
(I.sub.2) of from about 0.1 to about 100 g/10 min; and wherein (a)
Component A has a density of from about 0.890 to about 0.920
g/cm.sup.3; and is an interpolymer of ethylene with at least one
C.sub.3-8 .alpha.-olefin; and (b) Component B has a density of from
about 0.900 to about 0.965 g/cm.sup.3, and is an interpolymer of
ethylene with at least one C.sub.3-8 .alpha.-olefin.
10. A cast film of claim 8, said interpolymer composition having a
density of from about 0.900 to about 0.935 g/cm.sup.3; a melt index
(I.sub.2) of from about 0.5 to about 10 g/10 min and an I10/I2 of
from about 6.8 to about 10.5; and wherein (a) Component A is
present in an amount of from about 25 to about 75% by weight based
on the combined weight of Components A and B; has a density of from
about 0.890 to about 0.910 g/cm.sup.3 has no high density fraction
measurable by TREF and is an interpolymer of ethylene with at least
one C.sub.3-8 .alpha.-olefin; and (b) Component B is present in an
amount of from about 25 to about 75% by weight based on the
combined weight of Components A and B; has a density of from about
0.915 to about 0.935 g/cm.sup.3; has a high density fraction
measurable by TREF and is an interpolymer of ethylene with at least
one C.sub.3-8 .alpha.-olefin.
11. A blown film of claim 8 wherein the film is fabricated using
tenter frames or the double bubble process.
12. A blown film of claim 11 wherein the film is a biaxially
stretched film.
13. A fiber made from an ethylene/.alpha.-olefin interpolymer
composition comprising; (A) an ethylene/.alpha.-olefin interpolymer
which; (i) has a narrow molecular weight distribution, defined as
an M.sub.w/M.sub.n of less than about 3, (ii) has a narrow
composition distribution breadth index, CDBI, (defined as the
weight percent of the polymer molecules having a comonomer content
within 50 percent of the median total molar comonomer content of
Component A) which is greater than about 50 percent; (iii) has a
degree of branching less than or equal to 2 methyls/1000 carbons in
about 15 percent or less by weight (based on the total weight of
Component A); (iv) has an aluminum residue content of less than or
equal to about 250 ppm present in the interpolymer composition, and
(v) is present in an amount of from about 15 to about 85% by weight
(based on the combined weight of Components A and B); and (B) an
ethylene/.alpha.-olefin interpolymer; which (i) has a broad
molecular weight distribution, defined as defined as an
M.sub.w/M.sub.n of greater than about 3, (ii) has a broad
composition distribution with a degree of branching less than or
equal to 2 methyls/1000 carbons in about 10 percent or more by
weight (based on the total weight of Component B); (iii) has a
degree of branching greater than or equal to 25 methyls/1000
carbons in about 25 percent or less by weight (based on the total
weight of Component B); and (iv) is present in an amount of from
about 15 to about 85% by weight based on the combined weight of
Components A and B; and wherein said fiber is a staple fiber, a
melt blown fiber or spun bonded fiber or gel spun fiber.
14. A structure made from the fiber of claim 13 wherein the
structure is a woven or non-woven fabric.
15. A fabric of claim 14 wherein the fabric is a spunlaced
fabric.
16. A fabric of claim 14 wherein the fabric is a blend of the
fibers of claim 9 with other fibers.
17. A fabric of claim 16 wherein said other fiber is cotton or PET
or combinations thereof.
18. An interpolymer blend composition having a density of from
about 0.940 to about 0.960 and a melt index (I2) of from about 3 to
about 100 g/10 min; comprising (A) one or more
ethylene/.alpha.-olefin interpolymers which; (i) has a narrow
molecular weight distribution, defined as an M.sub.w/M.sub.n of
less than about 3, (ii) has a narrow composition distribution
breadth index, CDBI, (defined as the weight percent of the polymer
molecules having a comonomer content within 50 percent of the
median total molar comonomer content of Component A) which is
greater than about 50 percent; (iii) has a degree of branching less
than or equal to 2 methyls/1000 carbons in about 15 percent or less
by weight (based on the total weight of Component A); (iv) has an
aluminum residue content of less than or equal to about 250 ppm
present in the interpolymer composition, and (v) is present in an
amount of from about from about 5 to about 50% by weight (based on
the combined weight of Components A and B; and (vi) has a density
of from about 0.850 to about 0.908 g/cm3; and (B) an
ethylene/.alpha.-olefin interpolymer; which (i) has a broad
molecular weight distribution, defined as defined as an
M.sub.w/M.sub.n of greater than about 3, (ii) has a broad
composition distribution with a degree of branching less than or
equal to 2 methyls/1000 carbons in about 10 percent or more by
weight (based on the total weight of Component B); (iii) has a
degree of branching greater than or equal to 25 methyls/1000
carbons in about 25 percent or less by weight (based on the total
weight of Component B); and (iv) is present in an amount of from
about 50 to about 95% by weight(based on the combined weight of
Components A and B); and wherein (C) said interpolymer composition
has an improvement in 23.degree. C. Izod Impact of at least 5% over
a blend of the same final melt index and density, but wherein the
density of Component A is greater than or equal to 0.909
g/cm.sup.3.
19. The interpolymer composition of claim 18 having a density of
from about 0.940 to about 0.955 and a melt index (I2) of from about
3 to about 50 g/10 min; and wherein (A) Component A is an
interpolymer of ethylene with at least one C.sub.3-8 .alpha.-olefin
and present in an amount of from about 7 to about 50% by weight
(based on the combined weight of Components A and B) and has a
density of from about 0.850 to about 0.906 g/cm3; and (B) Component
B is one or more homopolymers or interpolymers of ethylene and/or
at least one C.sub.3-8 .alpha.-olefin and is present in an amount
of from about 50 to about 93% by weight(based on the combined
weight of Components A and B); and wherein said interpolymer
composition has an improvement in 23.degree. C. Izod Impact of at
least 7% over a blend of the same final melt index and density, but
wherein the density of Component A is greater than or equal to
0.909 g/cm.sup.3.
20. The interpolymer composition of claim 18 having a density of
from about 0.940 to about 0.950 and a melt index (I2) of from about
3 to about 25 g/10 min; and wherein (A) Component A is an
interpolymer of ethylene with at least one C.sub.3-8 .alpha.-olefin
and present in an amount of from about 10 to about 50% by weight
(based on the combined weight of Components A and B) and has a
density of from about 0.850 to about 0.903 g/cm3; and (B) Component
B is one or more homopolymers or interpolymers of ethylene and/or
at least one C.sub.3-8 .alpha.-olefin and is present in an amount
of from about 50 to about 90% by weight(based on the combined
weight of Components A and B); and wherein said interpolymer
composition has an improvement in 23.degree. C. Izod Impact of at
least 10% over a blend of the same final melt index and density,
but wherein the density of Component A is greater than or equal to
0.909 g/cm.sup.3
21. The interpolymer composition of claim 18 having a density of
from about 0.930 to about 0.965 and a melt index (I2) of from about
0.5 to about 4 g/10 min; and wherein (A) Component A is an
interpolymer of ethylene with at least one C.sub.3-8 .alpha.-olefin
and present in an amount of from about 10 to about 50% by weight
(based on the combined weight of Components A and B) and has a
density of from about 0.850 to about 0.903 g/cm3; and (B) Component
B is one or more homopolymers or interpolymers of ethylene and/or
at least one C.sub.3-8 .alpha.-olefin and is present in an amount
of from about 50 to about 90% by weight(based on the combined
weight of Components A and B); and wherein said interpolymer
composition has an improvement in 0.degree. C. Izod Impact of at
least 5% over a blend of the same final melt index and density, but
wherein the density of Component A is greater than or equal to
0.909 g/cm.sup.3.
22. The interpolymer composition of claim 18 having a density of
from about 0.935 to about 0.945 and a melt index (I2) of from about
0.5 to about 3.3 g/10 min; and wherein (A) Component A is an
interpolymer of ethylene with at least one C.sub.3-8 .alpha.-olefin
and present in an amount of from about 15 to about 50% by weight
(based on the combined weight of Components A and B) and has a
density of from about 0.850 to about 0.890 g/cm3; and (B) Component
B is one or more homopolymers or interpolymers of ethylene and/or
at least one C.sub.3-8 .alpha.-olefin and is present in an amount
of from about 50 to about 85% by weight(based on the combined
weight of Components A and B); and wherein said interpolymer
composition has an improvement in -20.degree. C. Izod Impact of at
least 5% over a blend of the same final melt index and density, but
wherein the density of Component A is greater than or equal to
0.909 g/cm.sup.3.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation in part of application
Ser. No. 09/121,689 filed Jul. 23, 1998, which is a division of
application Ser. No. 08/747,419 filed Nov. 12, 1996, now U.S. Pat.
No. 5,844,045, which is a continuation of application Ser. No.
08/010,958 filed Jan. 29, 1993 now abandoned, all of which are
incorporated herein by reference in their entirety. This
application is related to pending application Ser. No. 07/776,130,
filed Oct. 15, 1991, now U.S. Pat. No. 5,272,236, to pending
application Ser. No. 07/815,716, filed Dec. 30, 1991, now
abandoned, and to pending application Ser. No. 07/939,281, filed
Sep. 2, 1992, now U.S. Pat. No. 5,278,272, the disclosures of all
of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates to articles prepared from ethylene
interpolymers made by an interpolymerization process. The processes
utilize at least one homogeneous polymerization catalyst and at
least one heterogeneous polymerization catalyst in separate
reactors connected in series or in parallel. Interpolymers produced
from such processes are thermoplastic and have surprisingly
beneficial properties, including improved room and low temperature
impact and tear properties, high modulus and higher crystallization
temperatures, while maintaining equivalent or improved
processability as compared to the individual blend components The
resins of the present invention are useful in making molded or
shaped articles, film, and the like.
BACKGROUND OF THE INVENTION
[0003] There are known several polymerization processes for
producing polyethylene and ethylene interpolymers, including
suspension, gas-phase and solution processes. Of these, the
solution process is of commercial significance due to the
advantages described in U.S. Pat. No. 4,330,646 (Sakurai et al.),
the disclosure of which is incorporated herein by reference. A most
advantageous solution process would be found if the temperature of
the polymerization solution could be increased and the properties
of the polymers suitably controlled. U.S. Pat. No. 4,314,912
(Lowery et al.), the disclosure of which is incorporated herein by
reference, describes a Ziegler-type catalyst suitable for use in
high temperature solution polymerization processes. U.S. Pat. No.
4,612,300 (Coleman, III), the disclosure of which is incorporated
herein by reference, and U.S. Pat. No. 4,330,646 describe a
catalyst and solution polymerization process for producing
polyethylenes having a narrow molecular weight distribution. U.S.
Pat. No. 4,330,646 also describes a process for producing
polyethylenes with a broader molecular weight distribution in a
solution process. These processes are based on heterogeneous
Ziegler type catalysts, which produce interpolymers with broad
composition distributions regardless of their molecular weight
distribution. Such ethylene polymers have deficiencies in some
properties, for instance, poor transparency and poor anti-blocking
properties.
[0004] Solution polymerization processes for producing ethylene
interpolymers with narrow composition distributions are also known.
U.S. Pat. No. 4,668,752 (Tominari et al.), the disclosure of which
is incorporated herein by reference, describes the production of
heterogeneous ethylene copolymers with characteristics which
include a narrower composition distribution than conventional
heterogeneous copolymers. The utility of such polymer compositions
in improving mechanical, optical and other important properties of
formed or molded objects is also described. The complex structures
of the copolymers necessary to achieve such advantages are finely
and difficultly controlled by nuances of catalyst composition and
preparation; any drift in which would cause a significant loss in
the desired properties. U.S. Pat. No. 3,645,992 (Elston), the
disclosure of which is incorporated herein by reference, describes
the preparation of homogeneous polymers and interpolymers of
ethylene in a solution process operated at temperatures of less
than 100.degree. C. These polymers exhibit a "narrow composition
distribution", a term defined by a comonomer distribution that,
within a given polymer molecule, and between substantially all
molecules of the copolymer, is the same. The advantages of such
copolymers in improving optical and mechanical properties of
objects formed from them is described. These copolymers, however,
have relatively low melting points and poor thermal resistance.
[0005] U.S. Pat. No. 4,701,432 (Welborn, Jr.), the disclosure of
which is incorporated herein by reference, describes a catalyst
composition for the production of ethylene polymers having a varied
range of composition distributions and/or molecular weight
distributions. Such compositions contain a metallocene and a
non-metallocene transition metal compound supported catalyst and an
aluminoxane. U.S. Pat. No. 4,659,685 (Coleman, III et al.), the
disclosure of which is incorporated herein by reference, describes
catalysts which are composed of two supported catalysts (one a
metallocene complex supported catalyst and the second a
non-metallocene transition metal compound supported catalyst) and
an aluminoxane. The disadvantages of such catalysts in the
commercial manufacture of ethylene polymers are primarily twofold.
Although, the choice of the metallocene and a non-metallocene
transition metal compounds and their ratio would lead to polymers
of controlled molecular structure, the broad range of ethylene
polymer structures required to meet all the commercial demands of
this polymer family would require a plethora of catalyst
compositions and formulations. In particular, the catalyst
compositions containing aluminoxanes (which are generally required
in high amounts with respect to the transition metal) are
unsuitable for higher temperature solution processes as such amount
of the aluminum compounds result in low catalyst efficiencies and
yield ethylene polymers with low molecular weights and broad
molecular weight distributions.
[0006] Thus, it would be desirable to provide an economical
solution process, which would provide ethylene interpolymers with
controlled composition and molecular weight distributions. It would
be additionally desirable to provide a process for preparing such
interpolymers with reduced complexity and greater flexibility in
producing a full range of interpolymer compositions in a
controllable fashion.
[0007] Useful articles which could be made from such interpolymer
compositions include films (e.g., cast film, blown film or
extrusion coated types of film), fibers (e.g., staple fibers, melt
blown fibers or spunbonded fibers (using, e.g., systems as
disclosed in U.S. Pat. No. 4,340.563. U.S. Pat. No. 4,663,220, U.S.
Pat. No. 4,668,566, or U.S. Pat. No. 4,322,027, all of which are
incorporated herein by reference), and gel spun fibers (e.g., the
system disclosed in U.S. Pat. No. 4,413,110, incorporated herein by
reference)), both woven and nonwoven fabrics (e.g., spuntaced
fabrics disclosed in U.S. Pat. No. 3,485,706, incorporated herein
by reference) or structures made from such fibers (including, e.g.,
blends of these fibers with other fibers, e.g., PET or cotton)),
and molded articles (e.g., blow molded articles, injection molded
articles and rotational molded articles).
[0008] Rotational molding (also known as rotomolding), is used to
manufacture hollow objects from thermoplastics. In the basic
process of rotational molding, pulverized polymer is placed in a
mold. While the mold is being rotated, the mold is heated and then
cooled. The mold can be rotated uniaxially or biaxially and is
usually rotated biaxially. i.e. rotated about two perpendicular
axes simultaneously. The mold is typically heated externally and
then cooled while being rotated. As such, rotomolding is a zero
shear process and involves the tumbling, heating and melting of
thermoplastic powder, followed by coalescence, fusion or sintering
and cooling. In this manner, articles may be obtained which are
complicated, large in size, and uniform in wall thickness.
[0009] Many compositions have been employed in rotational molding.
For example, U.S. Pat. No. 4,857,257 teaches rotational molding
compositions comprising polyethylene, peroxide cross-linkers and a
metal cationic compound while U.S. Pat. No. 4,587,318 teaches
crosslinked compositions comprising ethylene terpolymer and organic
peroxide.
[0010] Research disclosure, RD-362010-A describes blends of
traditionally catalyzed polyolefins, especially very low or
ultralow density polyethylenes with densities of 0.89 to 0.915
g/cm3 with polyolefins made using single-site, metallocene
catalysts. These blends are especially suited to rotational molding
providing good control over the balance of processability and
improved environmental stress crack resisitance (ESCR) and tear
properties.
[0011] In the case of rotational molding, the final density and
melt index of the compositions is typically a compromise between
processability and end-product properties. Conventional knowledge
teaches that increasing polymer density (or modulus) results in
decreasing impact, and increasing melt index (or decreasing
molecular weight) results in increased processability and
corresponding decreases in ESCR and impact. Furthermore, increased
branching has been known to result in inferior processability. As a
result, one typically must choose which property to increase with
the expectation that the other property must be decreased.
[0012] Thus it would be highly desirable to prepare molding
compositions with improved processability (even when the zero or
low shear viscosity or branching is increased) and improved room
and low temperature impact and tear properties, improved optical
properties, high modulus and higher thermal stability's, without
necessarily decreasing the polymer density. Such improvements would
be advantageous in a wide range of applications, including but not
limited to molding and especially rotational molding., films,
fibers and foams.
SUMMARY OF THE INVENTION
[0013] We have now discovered fabricated articles prepared by a
polymerization processes for preparing interpolymer compositions of
controlled composition and molecular weight distributions. The
processes utilize at least one homogeneous polymerization catalyst
and at least one heterogeneous polymerization catalyst in separate
reactors connected in series or in parallel.
[0014] The First Process comprises the steps of:
[0015] 1. A process for preparing an ethylene/.alpha.-olefin
interpolymer composition, comprising the steps of:
[0016] (A) reacting by contacting ethylene and at least one other
.alpha.-olefin under solution polymerization conditions in the
presence of a homogeneous catalyst composition containing either no
aluminum cocatalyst or only a small amount of aluminum cocatalyst
in at least one reactor to produce a solution of a first
interpolymer which has a narrow composition distribution and a
narrow molecular weight distribution,
[0017] B) reacting by contacting ethylene and at least one other
.alpha.-olefin under solution polymerization conditions and at a
higher polymerization reaction temperature than used in step (A) in
the presence of a heterogeneous Ziegler catalyst in at least one
other reactor to produce a solution of a second interpolymer which
has a broad composition distribution and a broad molecular weight
distribution, and
[0018] (C) combining the solution of the first interpolymer with
the solution of the second interpolymer to form a high temperature
polymer solution comprising the ethylene/.alpha.-olefin
interpolymer composition, and
[0019] (D) removing the solvent from the polymer solution of step
(C) and recovering the ethylene/.alpha.-olefin interpolymer
composition.
[0020] These polymerizations are generally carried out under
solution conditions to facilitate the intimate mixing of the two
polymer-containing streams. The homogeneous catalyst is chosen from
those metallocene-type catalysts, which are capable of producing
ethylene/.alpha.-olefin interpolymers of sufficiently high
molecular weight under solution process polymerization conditions
(e.g., temperatures greater than or equal to about 100.degree. C.).
The heterogeneous catalyst is also chosen from those catalysts,
which are capable of efficiently producing the polymers under high
temperature (e.g., temperatures greater than or equal to about
180.degree. C.) solution process conditions.
[0021] In addition, there is provided a second process for
preparing interpolymer compositions of controlled composition and
controlled molecular weight distributions.
[0022] The Second Process comprises the steps of:
[0023] A process for preparing an ethylene/.alpha.-olefin
interpolymer composition, comprising the steps of:
[0024] (A) polymerizing ethylene and at least one other
.alpha.-olefin in a solution process under suitable solution
polymerization temperatures and pressures in at least one reactor
containing a homogeneous catalyst composition containing either no
aluminum cocatalyst or only a small amount of aluminum cocatalyst
to produce a first interpolymer solution comprising a first
interpolymer having has a narrow composition distribution and a
narrow molecular weight distribution, and
[0025] (B) sequentially passing the interpolymer solution of (A)
into at least one other reactor containing a heterogeneous Ziegler
catalyst, ethylene and at least one other .alpha.-olefin under
solution polymerization conditions and at a polymerization
temperature higher than that used in (A), to form a high
temperature polymer solution comprising the ethylene/.alpha.-olefin
interpolymer composition, and
[0026] (C) removing the solvent from the polymer solution of step
(B) and recovering the ethylene/.alpha.-olefin interpolymer
composition.
[0027] In either process, the homogeneous catalyst composition
preferably exhibits a high reactivity ratio and very readily
incorporates higher .alpha.-olefins.
[0028] The homogeneous catalysts employed in the production of the
homogeneous ethylene interpolymer are desirably derived from
monocyclopentadienyl complexes of the Group IV transition metals,
which contain a pendant bridging group, attached to the
cyclopentadienyl ring which acts as a bident ligand. Complex
derivatives of titanium in the +3 or +4 oxidation state are
preferred.
[0029] In another aspect of this invention, there are provided
novel interpolymers of ethylene and at least one .alpha.-olefin,
wherein the interpolymers have controlled composition and molecular
weight distributions. The interpolymers have improved mechanical,
thermal and optical properties and, surprisingly, the polymer
compositions obtained by the processes described herein provide
superior properties to materials obtained by merely blending the
solid polymers obtained from process step (A) or (B) individually,
in the First Process listed above.
[0030] The novel polymer compositions of the present invention can
be ethylene or C.sub.3-C.sub.20 .alpha.-olefin homopolymers,
preferably propylene or, more preferably, interpolymers of ethylene
with at least one C.sub.3-C.sub.20 .alpha.-olefin and/or
C.sub.4-C.sub.18 diolefins. Interpolymers of ethylene and 1-octene
are especially preferred. The term "interpolymer" is used herein to
indicate a copolymer, or a terpolymer, or the like. That is, at
least one other comonomer is polymerized with ethylene to make the
interpolymer.
[0031] In another aspect of the invention, thermoplastic
compositions have been discovered which are especially suitable for
rotational and injection molding and have improved physical and/or
mechanical properties. In many cases, processability is also
improved during rotational molding, as reflected in, for example,
shorter cycle times, faster sintering, and/or the ability to
fabricate articles over wide ranges of processing temperatures. For
injection molding, the compositions may also exhibit shorter cycle
times due to decreased set up times.
[0032] Advantageously, the compositions often exhibit one or more
of the following: improved low temperature and/or room temperature
impact, improved environmental stress crack resistance, and
acceptable flexural and secant modulus, increased upper service
temperature.
[0033] The compositions of the present invention with improved
impact properties can also be utilized in other fabrication
processes including, but not limited to blow molding, calendaring,
pulltrusion, cast film, and blown film.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] FIG. 1 illustrates the step change increase in Izod Impact
(in this case measured at 0.degree. C.) when the density of the
homogeneous interpolymer blend component (Component 1) is below
0.909 g/cm.sup.3.
DETAILED DESCRIPTION OF THE INVENTION
[0035] All references herein to elements or metals belonging to a
certain Group refer to the Periodic Table of the Elements published
and copyrighted by CRC Press, Inc., 1989. Also any reference to the
Group or Groups shall be to the Group or Groups as reflected in
this Periodic Table of the Elements using the IUPAC system for
numbering groups.
[0036] Any numerical values recited herein include all values from
the lower value to the upper value in increments of one unit
provided that there is a separation of at least 2 units between any
lower value and any higher value. As an example, if it is stated
that the amount of a component or a value of a process variable
such as, for example, temperature, pressure, time and the like is,
for example, from 1 to 90, preferably from 20 to 80, more
preferably from 30 to 70, it is intended that values such as 15 to
85, 22 to 68, 43 to 51, 30 to 32 etc. are expressly enumerated in
this specification. For values which are less than one, one unit is
considered to be 0.0001, 0.001, 0.01 or 0.1 as appropriate. These
are only examples of what is specifically intended and all possible
combinations of numerical values between the lowest value and the
highest value enumerated are to be considered to be expressly
stated in this application in a similar manner.
[0037] The term "hydrocarbyl" as employed herein means any
aliphatic, cycloaliphatic, aromatic, aryl substituted aliphatic,
aryl substituted cycloaliphatic, aliphatic substituted aromatic, or
aliphatic substituted cycloaliphatic groups.
[0038] The term "hydrocarbyloxy" means a hydrocarbyl group having
an oxygen linkage between it and the carbon atom to which it is
attached.
[0039] The term "interpolymer" is used herein to indicate a polymer
wherein at least two different monomers are polymerized to make the
interpolymer. This includes copolymers, terpolymers, etc.
[0040] As used herein, "Izod impact strength" was measured
according to ASTM test D-256 conducted at a particular temperature,
"2% secant modulus" for films was measured according to ASTM test
D-790, "flexural modulus" was measured according to ASTM test
D-790, "heat distortion temperature" was measured according to ASTM
test D-648 (at 66 psi), "low shear viscosity" was measured at 0.1
s.sup.-1 shear rate using a dynamic mechanical spectrometer, "melt
index" was measured according to ASTM test D-1238 (190.degree. C.,
2.16 kg load), "density" was measured according to ASTM D-792, and
"Environmental Stress Crack Resistance" (ESCR-F50) was measured
according to ASTM D-1524 using 10% Igepal solution.
[0041] The homogeneous polymers and interpolymers used in the
present invention are herein defined as defined in U.S. Pat. No.
3,645,992 (Elston), the disclosure of which is incorporated herein
by reference. Accordingly, homogeneous polymers and interpolymers
are those in which the comonomer is randomly distributed within a
given interpolymer molecule and wherein substantially all of the
interpolymer molecules have the same ethylene/comonomer ratio
within that interpolymer, whereas heterogeneous interpolymers are
those in which the interpolymer molecules do not have the same
ethylene/comonomer ratio.
[0042] The term "narrow composition distribution" used herein
describes the comonomer distribution for homogeneous interpolymers
and means that the homogeneous interpolymers have only a single
melting peak and essentially lack a measurable "linear" polymer
fraction. The narrow composition distribution homogeneous
interpolymers can also be characterized by their SCBDI (Short Chain
Branch Distribution Index) or CDBI (Composition Distribution Branch
Index). The SCBDI or CBDI is defined as the weight percent of the
polymer molecules having a comonomer content within 50 percent of
the median total molar comonomer content. The CDBI of a polymer is
readily calculated from data obtained from techniques known in the
art, such as, for example, temperature rising elution fractionation
(abbreviated herein as "TREF") as described, for example, in Wild
et al, Journal of Polymer Science, Poly. Phys. Ed., Vol. 20, p. 441
(1982), or in U.S. Pat. No. 4,798,081, and U.S. Pat. No. 5,008,204
and WO 93/04486, the disclosures of all of which are incorporated
herein by reference. The SCBDI or CDBI for the narrow composition
distribution homogeneous interpolymers and copolymers of the
present invention is preferably greater than about 30 percent,
especially greater than about 50 percent. The narrow composition
distribution homogeneous interpolymers and copolymers used in this
invention essentially lack a measurable "high density" (i.e.,
"linear" or homopolymer) fraction as measured by the TREF
technique. The homogeneous interpolymners and polymers have a
degree of branching less than or equal to 2 methyls/1000 carbons in
about 15 percent (by weight) or less, preferably less than about 10
percent (by weight), and especially less than about 5 percent (by
weight).
[0043] The term "broad composition distribution" used herein
describes the comonomer distribution for heterogeneous
interpolymers and means that the heterogeneous interpolymers have a
"linear" fraction and that the heterogeneous interpolymers have
multiple melting peaks (i.e., exhibit at least two distinct melting
peaks). The heterogeneous interpolymers and polymers have a degree
of branching less than or equal to 2 methyls/1000 carbons in about
10 percent (by weight) or more, preferably more than about 15
percent (by weight), and especially more than about 20 percent (by
weight). The heterogeneous interpolymers also have a degree of
branching equal to or greater than 25 methyls/1000 carbons in about
25 percent or less (by weight), preferably less than about 15
percent (by weight), and especially less than about 10 percent (by
weight).
[0044] The homogeneous polymers and interpolymers used to make the
novel polymer compositions used in the present invention can be
ethylene or C3-C20 .alpha.-olefin homopolymers, preferably
propylene, or, more preferably, interpolymers of ethylene with at
least one C.sub.3-C.sub.20 .alpha.-olefin and/or C.sub.4-C.sub.18
diolefins. Homogeneous copolymers of ethylene and propylene,
butene-1, hexene-1, 4-methyl-1-pentene and octene-1 are preferred
and copolymers of ethylene and 1-octene are especially
preferred.
[0045] Either, or both, of the homogeneous ethylene polymer and the
heterogeneous ethylene polymer can be an ethylene homopolymer or
C3-C20 .alpha.-olefin homopolymer, preferably propylene.
Preferably, however, either the homogeneous ethylene polymer or the
heterogeneous ethylene polymer is an ethylene/alpha-olefin
interpolymer. Ethylene polymer compositions wherein both the
homogeneous ethylene polymer and the heterogeneous ethylene polymer
are ethylene/alpha-olefin interpolymers are especially
preferred.
[0046] The homogeneous ethylene polymer(s) and the heterogeneous
ethylene polymer(s) used in the compositions described herein can
each be made separately in different reactors, and subsequently
blended together to make the interpolymer compositions of the
present invention, by for example melt or dry blending. Preferably,
though, the homogeneous ethylene polymer(s) and the heterogeneous
ethylene polymer(s) used in the compositions described herein are
made in a multiple reactor scheme, operated either in parallel or
in series. In the multiple reactor scheme, at least one of the
reactors makes the homogeneous ethylene polymer and at least one of
the reactors makes the heterogeneous ethylene polymer. In a
preferred mode of operation, the reactors are operated in a series
configuration to make most advantage of the high polymerization
temperatures allowed by the heterogeneous catalyst. When the
reactors are connected in series, the polymerization reaction
product from step (A) is fed directly (i.e., sequentially) into the
reactor(s) for step (B) along with the ethylene/.alpha.-olefin
reactants and heterogenous catalyst and solvent.
[0047] Other unsaturated monomers usefully polymerized according to
the present invention include, for example, ethylenically
unsaturated monomers, conjugated or nonconjugated dienes, polyenes,
etc. Preferred monomers include the C.sub.2-C.sub.10
.alpha.-olefins especially ethylene, 1-propene, 1-butene, 1-hexene,
4-methyl-1-pentene, and 1-octene. Other preferred monomers include
styrene, halo- or alkyl substituted styrenes,
vinylbenzocyclobutane, 1,4-hexadiene, cyclopentene, cyclohexene and
cyclooctene.
[0048] The density of the ethylene polymer compositions for use in
the present invention is measured in accordance with ASTM D-792 and
is generally from about 0.87 g/cm.sup.3 to about 0.965 g/cm.sup.3,
preferably from about 0.88 g/cm.sup.3 to about 0.95 g/cm.sup.3, and
especially from about 0.90 g/cm.sup.3 to about 0.935 g/cm.sup.3.
The density of the homogeneous ethylene polymer used to make the
ethylene polymer compositions is generally from about 0.865
g/cm.sup.3 to about 0.92 g/cm.sup.3, preferably from about 0.88
g/cm.sup.3 to about 0.915 g/cm.sup.3, and especially from about
0.89 g/cm.sup.3 to about 0.91 g/cm.sup.3. The density of the
heterogeneous ethylene polymer used to make the ethylene polymer
compositions is generally from about 0.9 g/cm.sup.3 to about 0.965
g/cm.sup.3, preferably from about 0.9 g/cm.sup.3 to about 0.95
g/cm.sup.3, and especially from about 0.915 g/cm.sup.3 to about
0.935 g/cm.sup.3.
[0049] Generally, the amount of the ethylene polymer produced using
the homogeneous catalyst and incorporated into the ethylene polymer
composition is from about 15 percent to about 85 percent, by weight
of the composition, preferably about 25 percent to about 75
percent, by weight of the composition.
[0050] The molecular weight of the ethylene polymer compositions
for use in the present invention is conveniently indicated using a
melt index measurement according to ASTM D-1238, Condition 190
C/2.16 kg (formally known as "Condition (E)" and also known as
I.sub.2). Melt index is inversely proportional to the molecular
weight of the polymer. Thus, the higher the molecular weight, the
lower the melt index, although the relationship is not linear. The
melt index for the ethylene polymer compositions used herein is
generally from about 0.1 grams/10 minutes (g/10 min) to about 100
g/10 min, preferably from about 0.3 g/10 min to about 30 g/10 min,
and especially from about 0.5 g/10 min to about 10 g/10 min.
[0051] In an especially preferred embodiment of the present
invention, the polymer compositions exhibit improvements in both
room and low temperature Izod impact. Such improvements are
especially important in the preparation of molded articles
including, but not limited to, rotomolded and injection molded
articles. Improvement in both room and low temperature Izod impact
is also important for other structures including, but not limited
to, films such as cast film and blown film, as well as fibers.
[0052] For blend compositions exhibiting an improvement in
23.degree. C. Izod impact, the final blend composition has a
density of from about 0.940 to about 0.960, preferably from about
0.940 to about 0.955, more preferably from about 0.940 to about
0.950 g/cm3 and a melt index (I2) of from about 3.0 to about 100,
preferably from about 3.0 to about 50, more preferably from about
3.0 to about 25 g/10 min. Such blend compositions comprise from
about 5 to about 50, preferably from about 7 to about 50, more
preferably from about 10 to about 50 percent by weight (based on
the combined weights of the heterogeneous and homogenous
interpolymer components) of one or more homogeneous interpolymers,
which has a density of from about 0.850 to about 0.908, preferably
from about 0.850 to about 0.906, more preferably from about 0.850
to about 0.903 g/cm3. Such blend compositions comprise from about
50 to about 95, preferably from about 50 to about 93, more
preferably from about 50 to about 90 percent by weight (based on
the combined weights of the heterogeneous and homogenous
interpolymer components) of one or more heterogeneous
interpolymers. We have surprisingly found that such blend
compositions exhibit an improvement in 23.degree. C. Izod Impact of
at least 5, preferably at 7, more preferably at least 10 and even
more preferably at least 25%, over a blend of the same final melt
index and density, but wherein the density of homogenous
interpolymer component(s) is greater than or equal to 0.909
g/cm.sup.3.
[0053] For blend compositions exhibiting an improvement in
0.degree. C. Izod impact, the final blend composition has a density
of from about 0.930 to about 0.960 g/cm3 and a melt index (I2) of
from about 0.5 to about 4.0 g/10 min. Such blend compositions
comprise from about 10 to about 50 percent by weight (based on the
combined weights of the heterogeneous and homogenous interpolymer
components) of one or more homogeneous interpolymers, which has a
density of from about 0.850 to about 0.903 g/cm3. Such blend
compositions comprise from about 50 to about 90 percent by weight
(based on the combined weights of the heterogeneous and homogenous
interpolymer components) of one or more heterogeneous
interpolymers. We have surprisingly found that such blend
compositions exhibit an improvement in 0.degree. C. Izod Impact of
at least 5, preferably at 7, more preferably at least 10 and even
more preferably at least 250%, over a blend of the same final melt
index and density, but wherein the density of homogenous
interpolymer component(s) is greater than or equal to 0.909
g/cm.sup.3.
[0054] For blend compositions exhibiting an improvement in
-20.degree. C. Izod impact, the final blend composition has a
density of from about 0.935 to about 0.945 g/cm3 and a melt index
(I2) of from about 0.5 to about 3.3 g/10 min. Such blend
compositions comprise from about 15 to about 50 percent by weight
(based on the combined weights of the heterogeneous and homogenous
interpolymer components) of one or more homogeneous interpolymers,
which has a density of from about 0.850 to about 0.890 g/cm3. Such
blend compositions comprise from about 50 to about 85 percent by
weight (based on the combined weights of the heterogeneous and
homogenous interpolymer components) of one or more heterogeneous
interpolymers. We have surprisingly found that such blend
compositions exhibit an improvement in -20.degree. C. Izod Impact
of at least 5, preferably at 7, more preferably at least 10 and
even more preferably at least 250%, over a blend of the same final
melt index and density, but wherein the density of homogenous
interpolymer component(s) is greater than or equal to 0.909
g/cm.sup.3.
[0055] While not wishing to be held by any theory, we believe the
observed step change in Izod impact which occurs when the density
of Component A is less than 0.909 g/cm3 (as illustrated in FIG. 1)
result from the occurrence of a particular solid state morphology
in Component A. This morphology has been described by Florey as a
"fringed micelle" structure, which occurs because the polymer
chains cannot fold upon themselves and form well ordered
spherulites.
[0056] Typically to select a final blend composition, one would
select Component A such that it has the claimed density range and
other property limitations as well as exhibiting a fringe micelle
structure. The additional blend component(s) are then selected on
the basis of the final desired modulus (typically based on final
blend density) and/or processability (typically based on final
molecular weight and molecular weight distribution) required for
the given application and method of fabrication. Additional
criteria for the selection of the additional blend component(s) may
also include ESCR, creep and other tensile properties.
[0057] Additives such as antioxidants (e.g., hindered phenols such
as, for example, Irganox.TM. 1010 a registered trademark of Ciba
Geigy), phosphites (e.g., Irgafos.TM. 168 a registered trademark of
Ciba Geigy). U.V. stabilizers, fire retardants, crosslinking
agents, blowing agents, compatibilizers, cling additives (e.g.,
polyisobutylene), slip agents (such as erucamide and/or
stearamide), antiblock additives, colorants, pigments, and the like
can also he used in the overall blend compositions employed in the
present invention.
[0058] For the compositions of the present invention having
improved impact properties, processing aids. which are also
referred to herein as plasticizers, can also be used in the overall
blend compositions. These processing aids include, but are not
limited to, the phthalates, such as dioctyl phthalate and
diisobutyl phthalate, natural oils such as lanolin, and paraffin,
naphthenic and aromatic oils obtained from petroleum refining, and
liquid resins from rosin or petroleum feedstocks. Exemplary classes
of oils useful as processing aids include white mineral oil (such
as Kaydol.TM. oil (available from and a registered trademark of
Witco), and Shellflex.TM. 371 naphthenic oil (available from and a
registered trademark of Shell Oil Company). Another suitable oil is
Tuflo.TM. oil (available from and a registered trademark of
Lyondell).
[0059] Tackifiers can also be included in the overall blend
compositions employed in the present invention to alter the
processing performance of the polymer and thus can extend the
available application temperature window of the articles. A
suitable tackifier may be selected on the basis of the criteria
outlined by Hercules in J. Simons, Adhesives Age, "The HMDA
Concept: A New Method for Selection of Resins", November 1996. This
reference discusses the importance of the polarity and molecular
weight of the resin in determining compatibility with the polymer.
In the case of substantially random interpolymers of at least one
.alpha.-olefin and a vinyl aromatic monomer, preferred tackifiers
will have some degree of aromatic character to promote
compatibility, particularly in the case of substantially random
interpolymers having a high content of the vinyl aromatic
monomer.
[0060] Tackifying resins can be obtained by the polymerization of
petroleum and terpene feedstreams and from the derivatization of
wood, gum, and tall oil rosin. Several classes of tackifiers
include wood rosin, tall oil and tall oil derivatives, and
cyclopentadiene derivatives, such as are described in United
Kingdom patent application GB 2,032,439A. Other classes of
tackifiers include aliphatic C5 resins, polyterpene resins,
hydrogenated resins, mixed aliphatic-aromatic resins, rosin esters,
natural and synthetic terpenes, terpene-phenolics, and hydrogenated
rosin esters.
[0061] Also included as a potential component of the polymer
compositions used in the present invention are various organic and
inorganic fillers, the identity of which depends upon the type of
application for which the molded parts are to be utilized. The
fillers can also be included in either blend Component A and/or
blend Component B or the overall blend compositions employed to
prepare the fabricated articles of the present invention.
Representative examples of such fillers include organic and
inorganic fibers such as those made from asbestos, boron, graphite,
ceramic, glass, metals (such as stainless steel) or polymers (such
as aramid fibers) talc, carbon black, carbon fibers, calcium
carbonate, alumina trihydrate, glass fibers, marble dust, cement
dust, clay. feldspar, silica or glass, fumed silica, alumina,
magnesium oxide, magnesium hydroxide, antimony oxide, zinc oxide,
barium sulfate, aluminum silicate, calcium silicate, titanium
dioxide, titanates, aluminum nitride, B203, nickel powder or
chalk.
[0062] Other representative organic or inorganic, fiber or mineral,
fillers include carbonates such as barium, calcium or magnesium
carbonate; fluorides such as calcium or sodium aluminum fluoride;
hydroxides such as aluminum hydroxide; metals such as aluminum,
bronze, lead or zinc; oxides such as aluminum, antimony, magnesium
or zinc oxide, or silicon or titanium dioxide; silicates such as
asbestos, mica, clay (kaolin or calcined kaolin), calcium silicate,
feldspar, glass (ground or flaked glass or hollow glass spheres or
microspheres or beads, whiskers or filaments), nepheline, perlite,
pyrophyllite, talc or wollastonite; sulfates such as barium or
calcium sulfate: metal sulfides, cellulose, in forms such as wood
or shell flour; calcium terephithialate: and liquid crystals.
Mixtures of more than one such filler may be used as well.
[0063] These additives are employed in functionally equivalent
amounts known to those skilled in the art. When used in proper
quantities such ingredients will typically not render the
composition unsuitable for rotational molding or injection
molding.
[0064] For example, the amount of antioxidant employed is that
amount which prevents the polymer or polymer blend from undergoing
oxidation at the temperatures and environment employed during
storage and ultimate use of the polymers. Such amount of
antioxidants is usually in the range of from 0.01 to 10, preferably
from 0.05 to 5, more preferably from 0.1 to 2 percent by weight
based upon the weight of the polymer or polymer blend. Similarly,
the amounts of any of the other enumerated additives are the
functionally equivalent amounts such as the amount to render the
polymer or polymer blend antiblocking, to produce the desired
result, to provide the desired color from the colorant or pigment.
Such additives can suitably be employed in the range of from 0.05
to 50, preferably from 0.1 to 35, more preferably from 0.2 to 20
percent by weight based upon weight of the polymer or polymer
blend, to the extent that they do not interfere with the enhanced
composition properties discovered by Applicants.
[0065] When used in proper quantities such ingredients will
typically not render the composition unsuitable for rotational
molding. However, large amounts of some ingredients, in particular
conventional fillers such as calcium carbonate, may harm the
rotational molding properties of the composition. For this reason,
it is preferable to add less than about 10, preferably less than
about 5 weight percent filler to the compositions used for
rotational molding.
[0066] The Homogeneous Catalysts
[0067] The homogeneous catalysts used in the invention are based on
those monocyclopentadienyl transition metal complexes described in
the art as constrained geometry metal complexes. These catalysts
are highly efficient, meaning that they are efficient enough such
that the catalyst residues left in the polymer do not influence the
polymer quality. Typically, less than or equal to about 10 ppm of
the metal atom (designated herein as "M") is detectable and, when
using the appropriate cocatalyst (e.g., one of the aluminoxanes
described herein) the detectable aluminum residue is less than or
equal to about 250 ppm. Suitable constrained geometry catalysts for
use herein preferably include constrained geometry catalysts as
disclosed in U.S. application Ser. No.: 545,403, filed Jul. 3,
1990; Ser. No. 758,654, filed Sep. 12, 1991; Ser. No. 758,660,
filed Sep. 12, 1991; Ser. No. 720,041, filed Jun. 24, 1991; and
Ser. No. 817,202, filed Jan. 6, 1992, the teachings of all of which
are incorporated herein by reference. The monocyclopentadienyl
transition metal olefin polymerization catalysts taught in U.S.
Pat. No. 5,026,798 (Canich), the teachings of which are
incorporated herein by reference, are also suitable for use in
preparing the polymers of the present invention.
[0068] The foregoing catalysts may be further described as
comprising a metal coordination complex comprising a metal of group
4 of the Periodic Table of the Elements and a delocalized
.pi.-bonded moiety substituted with a constrain-inducing moiety,
said complex having a constrained geometry about the metal atom
such that the angle at the metal between the centroid of the
delocalized, substituted .pi.-bonded moiety and the center of at
least one remaining substituent is less than such angle in a
similar complex containing a similar .pi.-bonded moiety lacking in
such constrain-inducing substituent, and provided further that for
such complexes comprising more than one delocalized, substituted
.pi.-bonded moiety, only one thereof for each metal atom of the
complex is a cyclic, delocalized, substituted .pi.-bonded moiety.
The catalyst further comprises an activating cocatalyst.
[0069] Preferred catalyst complexes correspond to the formula:
1
[0070] wherein:
[0071] M is a metal of group 4 of the Periodic Table of the
Elements;
[0072] Cp* is a cyclopentadienyl or substituted cyclopentadienyl
group bound in an .eta..sup.5 bonding mode to M;
[0073] Z is a moiety comprising boron, or a member of group 14 of
the Periodic Table of the Elements, and optionally sulfur or
oxygen, said moiety having up to 20 non-hydrogen atoms, and
optionally Cp* and Z together form a fused ring system;
[0074] X independently each occurrence is an anionic ligand group
having up to 30 non-hydrogen atoms;
[0075] n is 1 or 2; and
[0076] Y is an anionic or nonanionic ligand group bonded to Z and M
comprising nitrogen, phosphorus, oxygen or sulfur and having up to
20 non-hydrogen atoms, optionally Y and Z together form a fused
ring system.
[0077] More preferably still, such complexes correspond to the
formula: 2
[0078] wherein:
[0079] R' each occurrence is independently selected from the group
consisting of hydrogen, alkyl, aryl, and silyl, and combinations
thereof having up to 20 non-hydrogen atoms;
[0080] X each occurrence independently is selected from the group
consisting of hydride, halo, alkyl, aryl, silyl, aryloxy, alkoxy,
amide, siloxy and combinations thereof having up to 20 non-hydrogen
atoms;
[0081] Y is --O--, --S--, --NR*--, --PR*--, or a neutral two
electron donor ligand selected from the group consisting of OR*,
SR*, NR*.sub.2 or PR*.sub.2;
[0082] M is as previously defined; and
[0083] Z is SiR*.sub.2, CR*.sub.2, SiR*.sub.2SiR*.sub.2,
CR*.sub.2CR*.sub.2, CR*.dbd.CR*, CR*.sub.2SiR*.sub.2, BR*;
wherein
[0084] R* each occurrence is independently selected from the group
consisting of hydrogen, alkyl, aryl, silyl groups having up to 20
non-hydrogen atoms, and mixtures thereof, or two or more R* groups
from Y, Z, or both Y and Z form a fused ring system; and n is 1 or
2.
[0085] Most highly preferred complex compounds are amidosilane- or
amidoalkanediyl-compounds corresponding to the formula: 3
[0086] wherein:
[0087] M is titanium, zirconium or hafnium, bound in an h.sup.5
bonding mode to the cyclopentadienyl group;
[0088] R' each occurrence is independently selected from the group
consisting of hydrogen, alkyl and aryl and combinations thereof
having up to 7 carbon atoms, or silyl;
[0089] E is silicon or carbon;
[0090] X independently each occurrence is hydride, halo, alkyl,
aryl, aryloxy or alkoxy of up to 10 carbons, or silyl;
[0091] m is 1 or 2; and
[0092] n is 1 or 2.
[0093] Examples of the above most highly preferred metal
coordination compounds include compounds wherein the R' on the
amido group is methyl, ethyl, propyl, butyl, pentyl, hexyl,
(including isomers), norbornyl, benzyl, phenyl, etc.; the
cyclopentadienyl group is cyclopentadienyl, indenyl,
tetrahydroindenyl, fluorenyl, octahydrofluorenyl, etc.; R' on the
foregoing cyclopentadienyl groups each occurrence is hydrogen,
methyl, ethyl, propyl, butyl, pentyl, hexyl, (including isomers),
norbornyl, benzyl, phenyl, etc.; and X is chloro, bromo, iodo,
methyl, ethyl, propyl, butyl, pentyl, hexyl, (including isomers),
norbornyl, benzyl, phenyl, etc.
[0094] Specific compounds include:
(tert-butylamido)(tetramethyl-.eta..sup-
.5-cyclopentadienyl)-1,2-ethanediylzirconium dichloride,
(tert-butylamido)(tetramethyl-.eta..sup.5-cyclopentadienyl)-1,2-ethanediy-
ltitanium dichloride,
(methylamido)(tetramethyl-.eta..sup.5-cyclopentadien-
yl)-1,2-ethanediylzirconium dichloride,
(methylamido)(tetramethyl-.eta..su-
p.5-cyclopentadienyl)-1,2-ethanediyl-titanium dichloride,
(ethylamido)(tetramethyl-.eta.5-cyclopentadienyl)-methylenetitanium
dichloride,
(tertbutylamido)dibenzyl(tetramethyl-.eta..sup.5-cyclopentadi-
enyl)silanezirconium dibenzyl,
(benzylamido)dimethyl-(tetramethyl-.eta..su-
p.5-cyclopentadienyl)silanetitanium dichloride,
(phenylphosphido)dimethyl--
(tetramethyl-.eta..sup.5-cyclopentadienyl)silanezirconium dibenzyl,
(tertbutylado)dimethyl(tetramethyl-.eta..sup.5-cyclopentadienyl)silanetit-
anium dimethyl, and the like.
[0095] The catalyst compositions are derived from reacting the
metal complex compounds with a suitable activating agent or
cocatalyst or combination of cocatalysts. Suitable cocatalysts for
use herein include polymeric or oligomeric aluminoxanes, especially
aluminoxanes soluble in non-aromatic hydrocarbon solvent, as well
as inert, compatible, noncoordinating, ion forming compounds; or
combinations of polymeric/oligomeric aluminoxanes and inert,
compatible, noncoordinating, ion forming compounds. Preferred
cocatalysts contain inert, noncoordinating, boron compounds.
[0096] Ionic active catalyst species which can be used to
polymerize the polymers described herein correspond to the formula:
4
[0097] wherein:
[0098] M is a metal of group 4 of the Periodic Table of the
Elements;
[0099] Cp* is a cyclopentadienyl or substituted cyclopentadienyl
group bound in an .eta..sup.5 bonding mode to M;
[0100] Z is a moiety comprising boron, or a member of group 14 of
the Periodic Table of the Elements, and optionally sulfur or
oxygen, said moiety having up to 20 non-hydrogen atoms, and
optionally Cp* and Z together form a fused ring system;
[0101] X independently each occurrence is an anionic ligand group
having up to 30 non-hydrogen atoms;
[0102] n is 1 or 2; and
[0103] A--is a noncoordinating, compatible anion.
[0104] One method of making the ionic catalyst species which can be
utilized to make the polymers of the present invention involve
combining:
[0105] a) at least one first component which is a
mono(cyclopentadienyl) derivative of a metal of Group 4 of the
Periodic Table of the Elements as described previously containing
at least one substituent which will combine with the cation of a
second component (described hereinafter) which first component is
capable of forming a cation formally having a coordination number
that is one less than its valence, and
[0106] b) at least one second component which is a salt of a
Bronsted acid and a noncoordinating, compatible anion.
[0107] Compounds useful as a second component in the preparation of
the ionic catalysts useful in this invention can comprise a cation,
which is a Bronsted acid capable of donating a proton, and a
compatible noncoordinating anion. Preferred anions are those
containing a single coordination complex comprising a
charge-bearing metal or metalloid core which anion is relatively
large (bulky), capable of stabilizing the active catalyst species
(the Group 4 cation) which is formed when the two components are
combined and sufficiently labile to be displaced by olefinic,
diolefinic and acetylenically unsaturated substrates or other
neutral Lewis bases such as ethers, nitrites and the like.
Compounds containing anions which comprise coordination complexes
containing a single metal or metalloid atom are, of course, well
known and many, particularly such compounds containing a single
boron atom in the anion portion, are available commercially. In
light of this, salts containing anions comprising a coordination
complex containing a single boron atom are preferred.
[0108] Highly preferably, the second component useful in the
preparation of the catalysts of this invention may be represented
by the following general formula:
(L--H).sup.+[A].sup.-
[0109] wherein:
[0110] L is a neutral Lewis base;
[0111] (L--H).sup.+ is a Bronsted acid; and
[0112] [A].sup.- is a compatible, noncoordinating anion.
[0113] More preferably [A].sup.- corresponds to the formula:
[BQ.sub.q].sup.-
[0114] wherein:
[0115] B is boron in a valence state of 3; and
[0116] Q independently each occurrence is selected from the Group
consisting of hydride, dialkylamido, halide, alkoxide, aryloxide,
hydrocarbyl, and substituted-hydrocarbyl radicals of up to 20
carbons with the proviso that in not more than one occurrence is Q
halide.
[0117] Illustrative, but not limiting, examples of boron compounds
which may be used as a second component in the preparation of the
improved catalysts of this invention are trialkyl-substituted
ammonium salts such as triethylammonium tetraphenylborate,
tripropylammonium tetraphenylborate, tris(n-butyl)ammonium
tetraphenylborate, trimethylammonium tetrakis(p-tolyl)borate,
tributylammonium tetrakis(pentafluorophenyl)borate,
tripropylammonium tetrakis(2,4-dimethylphenyl)borate,
tributylammonium tetrakis(3,5-dimethylphenyl)borate,
triethylammonium tetrakis(3,5-di-trifluoromethylphenyl)borate and
the like. Also suitable are N,N-dialkylanilinium salts such as
N,N-dimethylanilinium tetraphenylborate, N,N-diethylanilinium
tetraphenylborate, N,N,2,4,6-pentamethylanilinium tetraphenylborate
and the like; dialkylammonium salts such as di(i-propyl)ammonium
tetrakis(pentafluorophenyl)borate, dicyclohexylammonium
tetraphenylborate and the like; and triarylphosphonium salts such
as triphenylphosphonium tetraphenylborate,
tris(methylphenyl)phosphonium tetrakis(pentafluorophen- yl)borate,
tris(dimethylphenyl)phosphonium tetraphenylborate and the like.
[0118] Preferred ionic catalysts are those having a limiting charge
separated structure corresponding to the formula: 5
[0119] wherein:
[0120] M is a metal of group 4 of the Periodic Table of the
Elements;
[0121] Cp* is a cyclopentadienyl or substituted cyclopentadienyl
group bound in an h.sup.5 bonding mode to M;
[0122] Z is a moiety comprising boron, or a member of group 14 of
the Periodic Table of the Elements, and optionally sulfur or
oxygen, said moiety having up to 20 non-hydrogen atoms, and
optionally Cp* and Z together form a fused ring system;
[0123] X independently each occurrence is an anionic ligand group
having up to 30 non-hydrogen atoms;
[0124] n is 1 or 2; and
[0125] XA*.sup.- is .sup.-X(B(C.sub.6F.sub.5).sub.3).
[0126] This class of cationic complexes can also be conveniently
prepared by contacting a metal compound corresponding to the
formula: 6
[0127] wherein:
[0128] Cp*, M, and n are as previously defined, with
tris(pentafluorophenyl)borane cocatalyst under conditions to cause
abstraction of X and formation of the anion
.sup.-X(B(C.sub.6F.sub.5).sub- .3).
[0129] Preferably X in the foregoing ionic catalyst is
C.sub.1-C.sub.10 hydrocarbyl, most preferably methyl or benzyl.
[0130] The preceding formula is referred to as the limiting, charge
separated structure. However, it is to be understood that,
particularly in solid form, the catalyst may not be fully charge
separated. That is, the X group may retain a partial covalent bond
to the metal atom, M. Thus, the catalysts may be alternately
depicted as possessing the formula: 7
[0131] The catalysts are preferably prepared by contacting the
derivative of a Group 4 metal with the
tris(pentafluorophenyl)borane in an inert diluent such as an
organic liquid. Tris(pentafluorphenyl)borane is a commonly
available Lewis acid that may be readily prepared according to
known techniques. The compound is disclosed in Marks, et al. J. Am.
Chem. Soc. 1991, 113, 3623-3625 for use in alkyl abstraction of
zirconocenes.
[0132] The homogeneous catalyst can contain either no aluminum
cocatalyst or only a small amount (i.e., from about 3:1 Al:M ratio
to about 100:1 Al:M ratio) of aluminum cocatalyst. For example, the
cationic complexes used as homogeneous catalysts may be further
activated by the use of an additional activator such as an
alkylaluminoxane. Preferred co-activators include
methylaluminoxane, propylaluminoxane, isobutylaluminoxane,
combinations thereof and the like. So-called modified
methylaluminoxane (MMAO) is also suitable for use as a cocatalyst.
One technique for preparing such modified aluminoxane is disclosed
in U.S. Pat. No. 4,960,878 (Crapo et al.), the disclosure of which
is incorporated herein by reference. Aluminoxanes can also be made
as disclosed in U.S. Pat. No. 4,544,762 (Kaminsky et al.); U.S.
Pat. No. 5,015,749 (Schmidt et al.); U.S. Pat. No. 5,041,583
(Sangokoya); U.S. Pat. No. 5,041,584 (Crapo et al.); and U.S. Pat.
No. 5,041,585 (Deavenport et al.), the disclosures of all of which
are incorporated herein by reference.
[0133] The homogeneous catalysts useful for the production of the
ethylene interpolymers of narrow composition and molecular weight
distribution may also be supported on an inert support. Typically,
the support can be any solid, particularly porous supports such as
talc or inorganic oxides, or resinous support materials such as a
polyolefin. Preferably, the support material is an inorganic oxide
in finely divided form.
[0134] Suitable inorganic oxide materials which are desirably
employed in accordance with this invention include Group IIA, IIIA,
IVA, or IVB metal oxides such as silica, alumina, and
silica-alumina and mixtures thereof. Other inorganic oxides that
may be employed either alone or in combination with the silica,
alumina or silica-alumina are magnesia, titania, zirconia, and the
like. Other suitable support materials, however, can be employed,
for example, finely divided polyolefins such as finely divided
polyethylene.
[0135] The metal oxides generally contain acidic surface hydroxyl
groups which will react with the homogeneous catalyst component
added to the reaction slurry. Prior to use, the inorganic oxide
support is dehydrated, i.e., subjected to a thermal treatment in
order to remove water and reduce the concentration of the surface
hydroxyl groups. The treatment is carried out in vacuum or while
purging with a dry inert gas such as nitrogen at a temperature of
about 100.degree. C. to about 1000.degree. C., and preferably, from
about 300.degree. C. to about 800.degree. C. Pressure
considerations are not critical. The duration of the thermal
treatment can be from about 1 to about 24 hours; however, shorter
or longer times can be employed provided equilibrium is established
with the surface hydroxyl groups.
[0136] The Heterogeneous Catalysts
[0137] The heterogeneous catalysts suitable for use in the
invention are typical supported, Ziegler-type catalysts which are
particularly useful at the high polymerization temperatures of the
solution process. Examples of such compositions are those derived
from organomagnesium compounds, alkyl halides or aluminum halides
or hydrogen chloride, and a transition metal compound. Examples of
such catalysts are described in U.S. Pat. No. 4,314,912 (Lowery,
Jr. et al.), U.S. Pat. No. 4,547,475 (Glass et al.), and U.S. Pat.
No. 4,612,300 (Coleman, III), the teachings of which are
incorporated herein by reference.
[0138] Particularly suitable organomagnesium compounds include, for
example, hydrocarbon soluble dihydrocarbylmagnesium such as the
magnesium dialkyls and the magnesium diaryls. Exemplary suitable
magnesium dialkyls include particularly n-butyl-sec-butylmagnesium,
diisopropylmagnesium, di-n-hexylmagnesium,
isopropyl-n-butyl-magnesium, ethyl-n-hexylmagnesium,
ethyl-n-butylmagnesium, di-n-octylmagnesium and others wherein the
alkyl has from 1 to 20 carbon atoms. Exemplary suitable magnesium
diaryls include diphenylmagnesium, dibenzylmagnesium and
ditolylmagnesium. Suitable organomagnesium compounds include alkyl
and aryl magnesium alkoxides and aryloxides and aryl and alkyl
magnesium halides with the halogen-free organomagnesium compounds
being more desirable.
[0139] Among the halide sources which can be employed herein are
the active non-metallic halides, metallic halides, and hydrogen
chloride.
[0140] Suitable non-metallic halides are represented by the formula
R'X wherein R' is hydrogen or an active monovalent organic radical
and X is a halogen. Particularly suitable non-metallic halides
include, for example, hydrogen halides and active organic halides
such as t-alkyl halides, allyl halides, benzyl halides and other
active hydrocarbyl halides wherein hydrocarbyl is as defined
hereinbefore. By an active organic halide is meant a hydrocarbyl
halide that contains a labile halogen at least as active, i.e., as
easily lost to another compound, as the halogen of sec-butyl
chloride, preferably as active as t-butyl chloride. In addition to
the organic monohalides, it is understood that organic dihalides,
trihalides and other polyhalides that are active as defined
hereinbefore are also suitably employed. Examples of preferred
active non-metallic halides include hydrogen chloride, hydrogen
bromide, t-butyl chloride, t-amyl bromide, allyl chloride, benzyl
chloride, crotyl chloride, methylvinyl carbinyl chloride,
a-phenylethyl bromide, diphenyl methyl chloride and the like. Most
preferred are hydrogen chloride, t-butyl chloride, allyl chloride
and benzyl chloride.
[0141] Suitable metallic halides which can be employed herein
include those represented by the formula MR.sub.y-aX.sub.a
wherein:
[0142] M is a metal of Groups IIB, IIIA or IVA of Mendeleev's
Periodic Table of Elements,
[0143] R is a monovalent organic radical,
[0144] X is a halogen,
[0145] Y has a value corresponding to the valence of M, and
[0146] a has a value from 1 to y.
[0147] Preferred metallic halides are aluminum halides of the
formula AlR.sub.3-aX.sub.a wherein:
[0148] each R is independently hydrocarbyl as hereinbefore defined
such as alkyl,
[0149] X is a halogen and
[0150] a is a number from 1 to 3.
[0151] Most preferred are alkylaluminum halides such as
ethylaluminum sesquichloride, diethylaluminum chloride,
ethylaluminum dichloride, and diethylaluminum bromide, with
ethylaluminum dichloride being especially preferred. Alternatively,
a metal halide such as aluminum trichloride or a combination of
aluminum trichloride with an alkyl aluminum halide or a trialkyl
aluminum compound may be suitably employed.
[0152] It is understood that the organic moieties of the
aforementioned organomagnesium, e.g., R", and the organic moieties
of the halide source, e.g., R and R', are suitably any other
organic radical provided that they do not contain functional groups
that poison conventional Ziegler catalysts.
[0153] The magnesium halide can be preformed from the
organomagnesium compound and the halide source or it can be formed
in situ in which instance the catalyst is preferably prepared by
mixing in a suitable solvent or reaction medium (1) the
organomagnesium component and (2) the halide source, followed by
the other catalyst components.
[0154] Any of the conventional Ziegler-Natta transition metal
compounds can be usefully employed as the transition metal
component in preparing the supported catalyst component. Typically,
the transition metal component is a compound of a Group IVB, VB, or
VIB metal. The transition metal component is generally, represented
by the formulas: TrX'.sub.4-q(OR.sup.1).sub.q,
TrX'.sub.4-qR.sup.2.sub.q, VOX'3 and VO(OR.sup.1).sub.3.
[0155] Tr is a Group IVB, VB, or VIB metal, preferably a Group IVB
or VB metal, preferably titanium, vanadium or zirconium,
[0156] q is 0 or a number equal to or less than 4,
[0157] X' is a halogen, and
[0158] R.sup.1 is an alkyl group, aryl group or cycloalkyl group
having from 1 to 20 carbon atoms, and
[0159] R.sup.2 is an alkyl group, aryl group, aralkyl group,
substituted aralkyls, and the like. The aryl, aralkyls and
substituted aralkys contain 1 to 20 carbon atoms, preferably 1 to
10 carbon atoms. When the transition metal compound contains a
hydrocarbyl group, R.sup.2, being an alkyl, cycloalkyl, aryl, or
aralkyl group, the hydrocarbyl group will preferably not contain an
H atom in the position beta to the metal carbon bond. Illustrative
but non-limiting examples of aralkyl groups are methyl, neo-pentyl,
2,2-dimethylbutyl, 2,2-dimethylhexyl; aryl groups such as benzyl;
cycloalkyl groups such as 1-norbornyl. Mixtures of these transition
metal compounds can be employed if desired.
[0160] Illustrative examples of the transition metal compounds
include TiCl.sub.4, TiBr.sub.4, Ti(OC.sub.2H.sub.5).sub.3Cl,
Ti(OC.sub.2H.sub.5)Cl.sub.3, Ti(OC.sub.4H.sub.9).sub.3Cl,
Ti(OC.sub.3H.sub.7).sub.2Cl.sub.2,
Ti(OC.sub.6H.sub.13).sub.2Cl.sub.2,
Ti(OC.sub.8H.sub.17).sub.2Br.sub.2, and
Ti(OC.sub.12H.sub.25)Cl.sub.3, Ti(O-i-C.sub.3H.sub.7).sub.4, and
Ti(O-n-C.sub.4H.sub.9).sub.4.
[0161] Illustrative examples of vanadium compounds include
VCl.sub.4, VOCl.sub.3, VO(OC.sub.2H.sub.5).sub.3, and
VO(OC.sub.4H.sub.9).sub.3.
[0162] Illustrative examples of zirconium compounds include
ZrCl.sub.4, ZrCl.sub.3(OC.sub.2H.sub.5),
ZrCl.sub.2(OC.sub.2H.sub.5).sub.2, ZrCl(OC.sub.2H.sub.5).sub.3,
Zr(OC.sub.2H.sub.5).sub.4, ZrCl.sub.3(OC.sub.4H.sub.9),
ZrCl.sub.2(OC.sub.4H.sub.9).sub.2, and
ZrCl(OC.sub.4H.sub.9).sub.3.
[0163] As indicated above, mixtures of the transition metal
compounds may be usefully employed, no restriction being imposed on
the number of transition metal compounds which may be contracted
with the support. Any halogenide and alkoxide transition metal
compound or mixtures thereof can be usefully employed. The
previously named transition metal compounds are especially
preferred with vanadium tetachloride, vanadium oxychloride,
titanium tetraisopropoxide, titanium tetrabutoxide, and titanium
tetraehloride being most preferred.
[0164] Suitable catalyst materials may also be derived from an
inert oxide supports and transition metal compounds. Examples of
such compositions suitable for use in the solution polymerization
process are described in U.S. Pat. No. 5,231,151, the entire
contents of which are incorporated herein by reference.
[0165] The inorganic oxide support used in the preparation of the
catalyst may be any particulate oxide or mixed oxide as previously
described which has been thermally or chemically dehydrated such
that it is substantially free of adsorbed moisture.
[0166] The specific particle size, surface area, pore volume, and
number of surface hydroxyl groups characteristic of the inorganic
oxide are not critical to its utility in the practice of the
invention. However, since such characteristics determine the amount
of inorganic oxide to be employed in preparing the catalyst
compositions, as well as affecting the properties of polymers
formed with the aid of the catalyst compositions, these
characteristics must frequently be taken into consideration in
choosing an inorganic oxide for use in a particular aspect of the
invention. In general, optimum results are usually obtained by the
use of inorganic oxides having an average particle size in the
range of about 1 to 100 microns, preferably about 2 to 20 microns;
a surface area of about 50 to 1,000 square meters per gram,
preferably about 100 to 400 square meters per gram; and a pore
volume of about 0.5 to 3.5 cm.sup.3 per gram; preferably about 0.5
to 2 cm.sup.3 per gram.
[0167] In order to further improve catalyst performance, surface
modification of the support material may be desired. Surface
modification is accomplished by specifically treating the support
material such as silica, aluminia or silica-alumina with an
organometallic compound having hydrolytic character. More
particularly, the surface modifying agents for the support
materials comprise the organometallic compounds of the metals of
Group IIA and IIIA of the Periodic Table. Most preferably the
organometallic compounds are selected from magnesium and aluminum
organometallics and especially from magnesium and aluminum alkyls
or mixtures thereof represented by the formulas and
R.sup.1MgR.sup.2 and R.sup.1R.sup.2AIR.sup.3 wherein each of
R.sup.1, R.sup.2 and R.sup.3 which may be the same or different are
alkyl groups, aryl groups, cycloalkyl groups, aralkyl groups,
alkoxide groups, alkadienyl groups or alkenyl groups. The
hydrocarbon groups R.sup.1, R.sup.2 and R.sup.3 can contain between
1 and 20 carbon atoms and preferably from 1 to about 10 carbon
atoms.
[0168] The surface modifying action is effected by adding the
organometallic compound in a suitable solvent to a slurry of the
support material. Contact of the organometallic compound in a
suitable solvent and the support is maintained from about 30 to 180
minutes and preferably form 60 to 90 minutes at a temperature in
the range of 20.degree. to 100.degree. C. The diluent employed in
slurrying the support can be any of the solvents employed in
solubilizing the organometallic compound and is preferably the
same.
[0169] In order to more readily produce interpolymer compositions
of controlled composition and molecular weight distribution, the
constrained-geometry component catalyst and the Ziegler-type
transition metal catalyst component should have different
reactivity ratios. The reactivity ratio of the homogeneous catalyst
may be higher than the reactivity ratio of the heterogeneous
catalyst. In such instances, the contribution of the narrow
composition and molecular weight distribution polymer molecules,
formed in the first reactor, to the whole interpolymer product
would yield improvements in thermal resistance and crystallization
behavior of the resin. Preferably, but not limiting, the reactivity
ratio of the homogeneous catalyst introduced into the first reactor
should be lower than the reactivity ratio of the heterogeneous
catalyst in order to have the most benefit of a simplified process
and to produce interpolymers of the most suitable compositions.
[0170] The reactivity ratios of the metallocenes and transition
metal components in general are obtained by methods well known such
as, for example, as described in "Linear Method for Determining
Monomer Reactivity Ratios in Copolymerization", M. Fineman and S.
D. Ross, J. Polymer Science 5, 259 (1950) or "Copolymerization", F.
R. Mayo and C. Walling, Chem. Rev. 46, 191 (1950), the disclosures
of both of which are incorporated herein in their entirety by
reference.
[0171] For example, to determine reactivity ratios, the most widely
used copolymerization model is based on the following equations:
8
[0172] where M.sub.1, M.sub.2 refer to monomer molecules and
M.sub.1* or M.sub.2* refer to a growing polymer chain to which
monomer M.sub.1 or M.sub.2 has most recently attached. M.sub.1 is
typically ethylene; M.sub.2 is typically an .alpha.-olefin
comonomer.
[0173] The k.sub.ij values are the rate constants for the indicated
reactions. In this case, k.sub.11 represents the rate at which an
ethylene unit inserts into a growing polymer chain in which the
previously inserted monomer unit was also ethylene. The reactivity
rates follows as: r.sub.1=k.sub.11/k.sub.12 and
r.sub.2=k.sub.22/k.sub.21 wherein k.sub.11, k.sub.12, k.sub.22, and
k.sub.21 are the rate constants for ethylene (1) or comonomer (2)
addition to a catalyst site where the last polymerized monomer is
ethylene (k.sub.1X) or comonomer (2) (k.sub.2X). A lower value of
r.sub.1 for a particular catalyst translates into the formation of
an interpolymer of higher comonomer content produced in a fixed
reaction environment. In a preferred embodiment of the invention,
the reactivity ratio, r.sub.1, of the homogeneous catalyst is less
than half that of the heterogeneous catalyst.
[0174] Therefore, in the desirable practice of the invention, the
homogeneous catalyst produces a polymer of higher comonomer content
than that of the polymer produced by the heterogeneous in a
reaction environment which is low in the concentration of the
comonomer. As the contents of the first reactor enter a second
reactor, the concentration of the comonomer in the second reactor
is reduced. Hence, the reaction environment in which the
heterogeneous catalyst forms polymer is such that a polymer
containing a lower comonomer content is produced. Under such
reaction conditions, the polymer so formed with have a well-defined
and narrow composition distribution and narrow molecular weight
distribution. The resulting whole interpolymer product can be
readily controlled by choice of catalysts, comonomers, and reaction
temperatures in an economical and reproducible fashion. In
addition, simple changes in monomer concentrations and conversions
in each reactor allows the manufacture of a broad range of
interpolymer products.
[0175] The heterogeneous polymers and interpolymers used to make
the novel polymer compositions of the present invention can be
ethylene homopolymers or C3-C20 .alpha.-olefin homopolymers,
preferably propylene, or, preferably, interpolymers of ethylene
with at least one C.sub.3-C.sub.20 .alpha.-olefin and/or
C.sub.4-C.sub.18 diolefins. Heterogeneous copolymers of ethylene
and 1-octene are especially preferred.
[0176] Polymerization
[0177] The polymerization conditions for manufacturing the polymers
of the present invention are generally those useful in the solution
polymerization process, although the application of the present
invention is not limited thereto. Slurry and gas phase
polymerization processes are also believed to be useful, provided
the proper catalysts and polymerization conditions are
employed.
[0178] Multiple reactor polymerization processes are particularly
useful in the present invention, such as those disclosed in U.S.
Pat. No. 3,914,342 (Mitchell), the disclosure of which is
incorporated herein by reference. The multiple reactors can be
operated in series or in parallel, with at least one constrained
geometry catalyst employed in one of the reactors and at least one
heterogeneous catalyst employed in at least one other reactor.
Preferably, the polymerization temperature of the constrained
geometry portion of the polymerization is lower than that of the
heterogeneous polymerization portion of the reaction.
[0179] Separation of the interpolymer compositions from the high
temperature polymer solution can be accomplished by use of
devolatilizing apparatus known to those skilled in the art.
Examples include U.S. Pat. No. 5,084,134 (Mattiussi et al.), U.S.
Pat. No. 3,014,702 (Oldershaw et al.), U.S. Pat. No. 4,808,262
(Aneja et al.), U.S. Pat. No. 4,564,063 (Tollar), U.S. Pat. No.
4,421,162 (Tollar) or U.S. Pat. No. 3,239,197 (Tollar), the
disclosures of which are incorporated herein in their entirety by
reference.
[0180] Applications of the Interpolymer Compositions
[0181] Films particularly benefit from such interpolymer
compositions. Films and film structures having the novel properties
described herein can be made using conventional hot blown film
fabrication techniques or other biaxial orientation process such as
tenter frames or double bubble processes. Conventional hot blown
film processes are described, for example, in The Encyclopedia of
Chemical Technology, Kirk-Othmer, Third Edition, John Wiley &
Sons, New York, 1981, Vol. 16, pp. 416-417 and Vol. 18, pp.
191-192, the disclosures of which are incorporated herein by
reference. Biaxial orientation film manufacturing process such as
described in a "double bubble" process as in U.S. Pat. No.
3,456,044 (Pahlke), and the processes described in U.S. Pat. No.
4,865,902 (Golike et al.), U.S. Pat. No. 4,352,849 (Mueller), U.S.
Pat. No. 4,820,557 (Warren), U.S. Pat. No. 4,927,708 (Herran et
al.), U.S. Pat. No. 4,963,419 (Lustig et al.), and U.S. Pat. No.
4,952,451 (Mueller), the disclosures of each of which are
incorporated herein by reference, can also be used to make novel
film structures from the novel interpolymer compositions. Novel
property combinations of such films include unexpectedly high
machine and cross direction secant modulus, both first and second
machine and cross direction yield, dart impact, cross direction
tensile, clarity, 20.degree. gloss, 45.degree. gloss, low haze, low
blocking force and low coefficient of friction (COF). In addition,
these interpolymer compositions have better resistance to melt
fracture (measured by determining onset of gross melt fracture
and/or surface melt fracture, as described in U.S. Pat. Nos.
5,272,236 and 5,278,272, the entire contents of which are herein
incorporated by reference.
[0182] In a preferred embodiment the compositions of the present
invention are used rotational molding and demonstrate improved room
and low temperature impact properties and improved processability.
Typically the rotational molding process with the above-described
compositions comprises the steps of preparing the composition. The
composition can be manufactured in powder or pellet form. For
rotational molding, powders are preferably used having a particle
size smaller than or equal to 35 mesh. The grinding may be done
cryogenically, if necessary. The composition is heated within the
mold as the mold is rotated. The mold is usually rotated biaxially,
i.e., rotated about two perpendicular axes simultaneously. The mold
is typically heated externally (generally with a forced air
circulating oven). The process steps include tumbling, heating and
melting of thermoplastic powder, followed by coalescence, fusion or
sintering and cooling to remove the molded article
[0183] The composition of the present invention can be processed in
most commercial rotational molding machines. The oven temperature
range during the heating step is from 400.degree. F. to 800.degree.
F., preferably about 500.degree. F. to about 700.degree. F., and
more preferably from about 575.degree. F. to about 650.degree.
F.
[0184] After the heating step the mold is cooled. The part must be
cooled enough to be easily removed from the mold and retain its
shape. Preferably the mold is removed from the oven while
continuing to rotate. Cool air is first blown on the mold. The air
can be an ambient temperature. After the air has started to cool
the mold for a controlled time period, a water spray can be used.
The water cools the mold more rapidly. The water used can be at
cold tap water temperature, usually from about 4.degree. C.
(40.degree. F.) to about 16.degree. C. (60.degree. F.). After the
water cooling step, another air cooling step may optionally be
used. This is usually a short step during which the equipment dries
with heat removed during the evaporation of the water.
[0185] The heating and cooling cycle times will depend on the
equipment used and the article molded. Specific factors include the
part thickness in the mold material. Typical conditions for an 1/8
inch thick part in a steel mold are to heat the mold in the oven
with air at about 316.degree. C. (600.degree. F.) for about 15
minutes. The part is then cooled in ambient temperature forced air
for about 8 minutes and then a tap water spray at about 10.degree.
C. (50.degree. F.) for about 5 minutes Optionally, the part is
cooled in ambient temperature forced air for an additional 2
minutes
[0186] During the heating and cooling steps the mold containing the
molded article is continually rotated. Typically this is done along
two perpendicular axes. The rate of rotation of the mold about each
axis is limited by machine capability and the shape of the article
being molded. A typical range of operation which can be used with
the present invention is to have the ratio of rotation of the major
axis to the minor axis of about 1:8 to 10:1 with a range of from
1:2 to 8:1 being preferred.
[0187] Rotational molded articles of the present invention can be
used where durability is essential in the sense that there is crack
and puncture resistance. Examples of articles which can be made
include gasoline tanks, large trash containers, and large bins or
silos for fertilizer, etc.
EXAMPLES
[0188] Useful physical property determinations made on the novel
interpolymer compositions described herein include:
[0189] Molecular Weight Distribution: measured by gel permeation
chromatography (GPC) on a Waters 150 C. high temperature
chromatographic unit equipped with three mixed porosity columns
(Polymer Laboratories 10.sup.3, 10.sup.4, 10.sup.5, and 10.sup.6),
operating at a system temperature of 140.degree. C. The solvent is
1,2,4-trichlorobenzene, from which 0.3 percent by weight solutions
of the samples are prepared for injection. The flow rate is 1.0
milliliters/minute and the injection size is 200 microliters.
[0190] The molecular weight determination is deduced by using
narrow molecular weight distribution polystyrene standards (from
Polymer Laboratories) in conjunction with their elution volumes.
The equivalent polyethylene molecular weights are determined by
using appropriate Mark-Houwink coefficients for polyethylene and
polystyrene (as described by Williams and Word in Journal of
Polymer Science, Polymer Letters, Vol. 6, (621) 1968, incorporated
herein by reference) to derive the following equation:
M.sub.polyethylene=a*(M.sub.polystyrene).sup.b.
[0191] In this equation, a=0.4316 and b=1.0. Weight average
molecular weight, M.sub.w, is calculated in the usual manner
according to the following formula: M.sub.w=R w.sub.i* M.sub.i,
where w.sub.i and M.sub.i are the weight fraction and molecular
weight, respectively, of the ith fraction eluting from the GPC
column.
[0192] For the interpolymer fractions and whole interpolymers
described herein, the term "narrow molecular weight distribution"
means that the M.sub.w/M.sub.n of the interpolymer (or fraction) is
less than about 3, preferably from about 2 to about 3. The
M.sub.w/M.sub.n of the "narrow molecular weight distribution"
interpolymer (or fraction) can also be described by the following
equation:
(M.sub.w/M.sub.n).ltoreq.(I.sub.10/I.sub.2)-4.63.
[0193] For the interpolymer fractions and whole interpolymers
described herein, the term "broad molecular weight distribution"
means that the M.sub.w/M.sub.n of the interpolymer (or fraction) is
greater than about 3, preferably from about 3 to about 5.
[0194] Crystallization Onset Temperature Measurement: measured
using differential scanning calorimetry (DSC). Each sample to be
tested is made into a compression molded plaque according to ASTM D
1928. The plaques are then thinly sliced at room temperature using
a Reichert Microtome or a razor blade to obtain samples having a
thickness of about 15 micrometers. About 5 milligrams of each
sample to be tested is placed in the DSC pan and heated to about
180.degree. C., held at that temperature for 3 minutes to destroy
prior heat history, cooled to -50.degree. C. at rate of 10.degree.
C./minute and held at that temperature for 2 minutes. The
crystallization onset temperature and the peak temperature are
recorded by the DSC as the temperature at which crystallization
begins and the temperature at which the sample is as fully
crystallized as possible, respectively, during the cooling period
from 180.degree. C. to -50.degree. C.
[0195] Melt flow ratio (MPR): measured by determining "I.sub.10"
(according to ASTM D-1238, Condition 190.degree. C./10 kg (formerly
known as "Condition (N)") and dividing the obtained I.sub.10 by the
I.sub.2. The ratio of these two melt index terms is the melt flow
ratio and is designated as I.sub.10/I.sub.2. For the homogeneous
portion of the interpolymer composition, the I.sub.10/I.sub.2 ratio
is generally greater than or equal to 5.63 and preferably from
about 5.8 to about 8.5. For the heterogeneous portion of the
interpolymer composition, the I.sub.10/I.sub.2 ratio is typically
from about 6.8 to about 9.5. The I.sub.10/I.sub.2 ratio for the
whole interpolymer compositions is typically from about 6.8 to
about 10.5.
[0196] 1 and 2% Secant Modulus for bar samples: using a method
similar to ASTM D 882, incorporated herein by reference, except
that 4 specimens are used, a 4 inch gauge length is used and the
conditioning period is 24 hours;
[0197] Clarity: measured by specular transmittance according to
ASTM D 1746, except that the samples are conditioned for 24
hours;
[0198] Haze: measured according to ASTM D 1003, incorporated herein
by reference;
[0199] Young's modulus, yield strength and elongation, break
strength and elongation, and toughness: using a method similar to
ASTM D 882, except that 4 specimens are used and are pulled at 20
inches per minute using a 2 inch gauge length;
[0200] Spencer Impact: using a method similar to ASTM D 3420,
procedure "B", incorporated herein by reference, except that the
maximum capacity is 1600 grams, the values are normalized for
sample thickness and the conditioning period has been shortened
from 40 hours to 24 hours; and
[0201] Tensile Tear: using a method similar to ASTM D 1938,
incorporated herein by reference, except that 4 specimens are
used.
[0202] Notched Izod Impact test ("NI", ASTM D256) indicates the
energy required to break notched specimens under standard
conditions. For MDPE and HDPE, NI can vary from about 0.5 to about
20 ft.lb/in, depending on the exact composition and temperature of
the test. Typically, values between 0.5 and 4 ft.lb/in correspond
to a brittle failure, while values above 6 ft.lb/in correspond to a
ductile failure. A ductile failure mode involves more energy
absorption due to the energy required to yield and stretch the
material. The impact energy concentrated at the tip of the notch
has to find a way to be dissipated, at a very high rate of
deformation. If the material contains rubbery material that can
elastically absorb energy through the interfaces with the harder
matrix, the initiated crack (the notch is actually the initiation
of the crack) will propagate as a yield and stretch mechanism. If
that is not the case, and the material is so stiff that cannot
elongate, the failure will be brittle.
Example 1
[0203] Homogeneous Catalyst Preparation
[0204] A known weight of the constrained-geometry organometallic
complex
[{(CH.sub.3).sub.4C.sub.5)}--(CH.sub.3).sub.2Si--N-(t-C.sub.4H.sub.9)]Ti(-
CH.sub.3).sub.2 was dissolved in Isopar E to give a clear solution
with a concentration of Ti of 0.005M. A similar solution of the
activator complex, tris(perfluoropheny)borane (0.010M) was also
prepared. A catalyst composition of a few mL total volume was
prepared by adding 2.0 mL of Isopar E solution of Ti reagent, 2.0
mL of the borane (for B:Ti=2:1) and 2 mL Isopar E to a 4 oz glass
bottle. The solution was mixed for a few minutes and transferred by
syringe to a catalyst injection cylinder on the polymerization
reactor.
[0205] Heterotieneous Catalyst Preparation
[0206] A heterogeneous Ziegler-type catalyst was prepared
substantially according to U.S. Pat. No. 4,612,300 (Ex. P.), by
sequentially adding to a volume of Isopar E, a slurry of anhydrous
magnesium chloride in Isopar E, a solution of EtAlC.sub.2 in
hexane, and a solution of Ti(O-iPr).sub.4 in Isopar E, to yield a
composition containing a magnesium concentration of 0.17M and a
ratio of Mg/Al/Ti of 40/12/3. An aliquot of this composition
containing 0.064 mmol of Ti which was treated with a dilute
solution of Et.sub.3Al to give an active catalyst with a final
Al/Ti ratio of 8/1. This slurry was then transferred to a syringe
until it was required for injection into the polymerization
reactor.
[0207] Polymerization
[0208] The polymerization described in this example demonstrates a
process for the use of two catalysts, employed sequentially, in two
polymerization reactors. A stirred, one-gallon (3.79 L) autoclave
reactor is charged with 2.1 L of Isopar.TM. E (made by Exxon
Chemical) and 388 mL of 1-octene comonomer and the contents are
heated to 150.degree. C. The reactor is next charged with ethylene
sufficient to bring the total pressure to 450 psig. A solution
containing 0.010 mmol of the active organometallic catalyst
described in the catalyst preparation section is injected into the
reactor using a high pressure nitrogen sweep. The reactor
temperature and pressure are maintained constant at the desired
final pressure and temperature by continually feeding ethylene
during the polymerization run and cooling the reactor as necessary.
After a 10 minute reaction time, the ethylene is shut off and the
reactor is depressured to 100 psig. Hydrogen is admitted to the
reactor and the contents heated. A slurry of the heterogeneous
catalyst containing 0.0064 mmol Ti prepared as described in the
catalyst preparation section is injected into the reactor using a
high pressure nitrogen sweep. The reactor is then continually fed
ethylene at 450 psig and the reaction temperature quickly rose to
185.degree. C. where the polymerization is sustained for an
additional 10 minutes. At this time the reactor is depressured and
the hot polymer-containing solution transferred into a
nitrogen-purged resin kettle containing 0.2 g Irganox 1010
antioxidant as a stabilizer. After removal of all the solvent in
vacuo, the sample is then weighed (yield 270 g) to determine
catalyst efficiencies (344300 g PE/g Ti).
Examples 2 and 3
[0209] Examples 2 and 3 are carried out as in Example 1 except
using the catalyst amounts and reactor temperatures described in
Table 1. The overall catalyst efficiencies are also shown in the
Table.
[0210] The polymer products of Examples 1-3 are tested for various
structural, physical and mechanical properties and the results are
given in Tables 2, 2A and 2B. Comparative Example A is Attane.RTM.
4001 polyethylene and comparative example B is Attane.RTM. 4003.
Both comparative examples are made by The Dow Chemical Company and
are commercial ethylene-octene copolymers produced under solution
process conditions using a typical commercial Ziegler-type
catalyst. The data show the polymers of the invention have more
narrow molecular weight distributions (M.sub.w/M.sub.n), higher
melting points, better crystallization properties (i.e., higher
crystallization onset temperatures) and, surprisingly, higher
modulus than the commercial comparative examples A and B. The
polymers of the invention surprisingly also show better optical
properties (i.e., higher clarity and lower haze) than the
comparative polymers, even though the polymers have about the same
density. In addition, the polymers of the invention show better
strength, toughness, tear and impact properties.
1TABLE 1 Process Conditions for Reactor #1 for Examples 1-3 Monomer
Reactor #1 H.sub.2 Volume Temp. (Reactor #1) Catalyst #1 Ex. (ml)
(.degree. C.) (mmol) (micromoles) 1 300 154 0 10 2 300 141 0 5 3
300 134 0 4
[0211]
2TABLE 1A Process Conditions for Reactor #2 for Examples 1-3
Overall Monomer Reactor # H.sub.2 Titanium Volume 2 Temp. (Reactor
#2) Catalyst #2 Efficiency Ex. (ml) (.degree. C.) (mmol)
(micromoles) (g PE/g Ti) 1 300 185 100 6.4 344300 2 300 191 100 9
410100 3 300 193 100 9 425600
[0212]
3TABLE 2 Examples 1-3 and Comparative Examples A and B Density Melt
Index (I.sub.2) MFR MWD Ex. (g/cm.sup.3) (g/10 min)
(I.sub.10/I.sub.2) M.sub.w M.sub.n (M.sub.w/M.sub.n) A 0.9136 1.06
8.33 122500 32500 3.77 B 0.9067 0.79 8.81 135300 31900 4.25 1
0.9112 1.07 7.4 115400 40000 2.89 2 0.9071 1.23 7.32 117600 40300
2.92 3 0.9062 1.08 7.46 124500 40100 3.1
[0213]
4TABLE 2A Crystl. Melting Onset Young's Clarity Temp. Temp. 2%
Secant Modulus (specular Haze Ex. (.degree. C.) (.degree. C.)
Modulus (psi) trans.) (%) A 121 105 20389 20425 0.85 67 B 121 105
13535 13541 1.32 56 1 124 111 25634 25696 2.7 65 2 123 111 28144
28333 5.5 62 3 123 111 28650 28736 3.7 61
[0214]
5TABLE 2B Yield Yield Break Break Toughness Spencer Tensile Ex.
Strength (psi) Elongation (%) Strength (psi) Elongation (%)
(ft.-lb.) Impact (psi) Strength (g/mil) A 1370 22 3133 693 1003 847
265 B 1108 24 2450 667 793 688 215 1 1541 16 4134 642 1155 897 311
2 1717 16 5070 658 1327 908 290 3 1756 15 4679 637 1234 903 311
Example 4
[0215] Homogeneous Catalyst Preparation
[0216] A known weight of the constrained-geometry organometallic
complex
[{(CH.sub.3).sub.4C.sub.5)}--(CH.sub.3).sub.2Si--N-(t-C.sub.4H.sub.9)]Ti(-
CH.sub.3).sub.2 is dissolved in Isopar E to give a clear solution
with a concentration of Ti of 0.001M. A similar solution of the
activator complex, tris(perfluoropheny)borane (0.002M) is also
prepared. A catalyst composition of a few mL total volume is
prepared by adding 1.5 mL of Isopar E solution of Ti reagent, 1.5
mL of the borane (for B:Ti=2:1) and 2 mL of a heptane solution of
methylaluminoxane (obtained commercially from Texas Alkyls as MMAO
Type 3A) containing 0.015 mmol A1 to a 4 oz glass bottle. The
solution is mixed for a few minutes and transferred by syringe to a
catalyst injection cylinder on the polymerization reactor.
[0217] Heterogeneous Catalyst Preparation
[0218] A heterogeneous Ziegler-type catalyst is prepared similarly
to that in Ex. 1 to give an active catalyst containing 0.009 mmol
Ti and a final Al/Ti ratio of 8/1. This slurry is then transferred
to a syringe in preparation for addition to the catalyst injection
cylinder on the polymerization reactor.
[0219] Polymerization
[0220] A stirred, one-gallon (3.79L) autoclave reactor is charged
with 2.1 L of Isopar.TM. E (made by Exxon Chemical) and 168 mL of
1-octene comonomer and the contents are heated to 120.degree. C.
The reactor is next charged with hydrogen and then with ethylene
sufficient to bring the total pressure to 450 psig. A solution
containing 0.0015 mmol of the active organometallic catalyst
described in the catalyst preparation section is injected into the
reactor using a high pressure nitrogen sweep. The reactor
temperature and pressure are maintained at the initial run
conditions. After a 10 minute reaction time, the ethylene is shut
off and the reactor is depressured to 100 psig. At this time, an
additional 168 mL of 1-octene is added to the reactor along with
additional hydrogen and the contents heated. A slurry of the
heterogeneous catalyst containing 0.009 mmol Ti prepared as
described in the catalyst preparation section is injected into the
reactor using a high pressure nitrogen sweep. The reactor is then
continually fed ethylene at 450 psig and the reaction temperature
quickly rises to 189.degree. C. where the polymerization is
sustained for an additional 10 minutes. At this time the reactor is
depressured and the hot polymer-containing solution transferred
into a nitrogen-purged resin kettle containing 0.2 g Irganox.TM.
1010 (a hindered phenolic antioxidant made by Ciba Geigy Corp.) as
a stabilizer. After removal of all the solvent in vacuo, the sample
is then weighed (yield 202 g) to determine catalyst efficiencies
(401630 g PE/g Ti).
Examples 5-7
[0221] Examples 5-7 are carried out as in Example 4 except using
the catalysts described in Example 1 and the catalyst amounts and
reactor conditions described in Tables 3 and 3A. The overall
catalyst efficiencies are also shown in Tables 3 and 3A.
[0222] These examples show that the reaction conditions can be
readily controlled to vary the composition and molecular weight
distribution of the polymer through a simple change in catalyst
amounts and monomer concentrations. Table 4 shows that the
interpolymers produced in these examples have a broader molecular
weight distribution than those of the earlier examples
demonstrating a unique feature of the process control. The physical
and mechanical properties still show surprising enhancements over
typical commercial copolymers of comparable molecular weight and
composition, particularly in strength, impact and tear properties.
Comparing examples 4 and 5 with comparative example A (as well as
by comparing examples 6 and 7 with comparative example B) shows
that the crystallization properties of the polymers of the
invention are largely unaffected by broadening the
M.sub.w/M.sub.n.
6TABLE 3 Process Conditions for Reactor #1 for Examples 4-7 Monomer
Reactor # Overall Titanium Volume 1 Temp. Reactor #1 Catalyst #1
Efficiency Ex. (ml) (.degree. C.) H.sub.2 (micromoles) (g PE/g Ti)
4 150 + 150 123 10 1.5 401630 5 150 + 150 139 50 5 422670 6 300 +
150 122 0 4 337241 7 300 + 150 133 100 6 434933
[0223]
7TABLE 3A Process Conditions for Reactor #2 for Examples 4-7
Monomer Reactor # Reactor #2 Overall Titanium Volume 2 Temp.
H.sub.2 Catalyst #2 Efficiency Ex. (ml) (.degree. C.) (mmol)
(micromoles) (g PE/g Ti) 4 150 + 150 189 300 9 401630 5 150 + 150
194 50 7.2 422670 6 300 + 150 189 400 9 337241 7 300 + 150 188 50
7.2 434933
[0224]
8TABLE 4 Interpolymer Properties Melt Index Density (I.sub.2) MFR
MWD Ex. (g/cm.sup.3) (g/10 min) (I.sub.10/I.sub.2) M.sub.w M.sub.n
(M.sub.w/M.sub.n) A 0.9136 1.06 8.33 122500 32500 3.77 4 0.913 1.12
7.45 117900 29400 4.003 5 0.9136 1.17 8.07 135000 42100 3.209 B
0.9067 0.79 8.81 135300 31900 4.25 6 0.9108 3.3 7.4 89700 28700
3.122 7 0.9081 1.53 10.17 125700 31000 4.057
[0225]
9TABLE 4A Cryst. Melting Onset Young's Clarity peak Temp. Modulus
2% Secant (specular Haze Ex. (.degree. C.) (.degree. C.) (psi)
Modulus trans.) (%) A 121 105 20425 20389 0.85 67 4 123 110 20333
20292 4.7 72 5 123 110 22648 22609 2.32 72 B 121 105 13541 13535
1.32 56 6 124 112 20100 20074 1.15 72 7 123 112 19836 19800 1.85
67
[0226]
10TABLE 4B Yield Break strength Yield strength Break Toughness
Spencer Tensile Ex. (psi) elongation (%) (psi) elongation (%)
(ft-lbs) Impact (psi) Tear (g/mil) A 1370 22 3133 693 1003 847 265
4 1468 19 3412 671 1012 977 271 5 1659 16 3608 738 1224 994 313 B
1108 24 2450 667 793 688 215 6 1354 16 2737 670 885 1022 255 7 1326
21 2353 729 914 821 238
Example 8
[0227] Homogeneous Catalyst Preparation
[0228] A known weight of the constrained-geometry organometallic
complex
[{(CH.sub.3).sub.4C.sub.5)}--(CH.sub.3).sub.2Si--N-(t-C.sub.4H.sub.9)]Ti(-
CH.sub.3).sub.2 is dissolved in Isopar E to give a clear solution
with a concentration of Ti of 0.001M. A similar solution of the
activator complex, tris(perfluoropheny)borane (0.002M) is also
prepared. A catalyst composition of a few mL total volume is
prepared by adding 1.5 mL of Isopar E solution of Ti reagent, 1.5
mL of the borane (for B:Ti=2:1) and 2 mL of a heptane solution of
methylaluminoxane (obtained commercially from Texas Alkyls as MMAO)
containing 0.015 mmol A1 to a 4 oz glass bottle. The solution is
mixed for a few minutes and transferred by syringe to a catalyst
injection cylinder on the polymerization reactor.
[0229] Heterogeneous Catalyst Preparation
[0230] A heterogeneous Ziegler-type catalyst is prepared similarly
to that in Ex. 1 to give an active catalyst containing 0.009 mmol
Ti and a final Al/Ti ratio of 8/1. This slurry is then transferred
to a syringe in preparation for addition to the catalyst injection
cylinder on the polymerization reactor.
[0231] Polymerization
[0232] The polymerization described in this example demonstrates a
process for the use of two catalysts, employed sequentially, in two
polymerization reactors. A stirred, one-gallon (3.79 L) autoclave
reactor is charged with 2.1 L of Isopar.TM. E (made by Exxon
Chemical) and 168 mL of 1-octene comonomer and the contents are
heated to 120.degree. C. The reactor is next charged with hydrogen
and then with ethylene sufficient to bring the total pressure to
450 psig. A solution containing 0.0015 mmol of the active
organometallic catalyst described in the catalyst preparation
section is injected into the reactor using a high pressure nitrogen
sweep. The reactor temperature and pressure are maintained at the
initial run conditions. After a 10 minute reaction time, the
ethylene is shut off and the reactor is depressured to 100 psig. At
this time, an additional 168 mL of 1-octene is added to the reactor
along with additional hydrogen and the contents heated. A slurry of
the heterogeneous catalyst containing 0.009 mmol Ti prepared as
described in the catalyst preparation section is injected into the
reactor using a high pressure nitrogen sweep. The reactor is then
continually fed ethylene at 450 psig and the reaction temperature
quickly rises to 189.degree. C. where the polymerization is
sustained for an additional 10 minutes. At this time the reactor is
depressured and the hot polymer-containing solution transferred
into a nitrogen-purged resin kettle containing 0.2 g Irganox.TM.
1010 (a hindered phenolic antioxidant made by Ciba Geigy Corp.) as
a stabilizer. After removal of all the solvent in vacuo, the sample
is then weighed (yield 202 g) to determine catalyst efficiencies
(401630 g PE/g Ti).
Examples 9-14
[0233] Examples 9-14 are carried out as in Example 8 except using
the catalysts described in Example 1 and the catalyst amounts and
reactor conditions described in Tables 5 and 5A. The overall
catalyst efficiencies are also shown in the Tables.
[0234] These examples show the ability to readily control the
reaction conditions to vary the composition and molecular weight
distribution of the polymer through a simple change in catalyst
amounts and monomer concentrations. The polymers produced in these
Examples show a broader molecular weight distribution than those of
the earlier examples showing a unique feature of the process
control. The physical and mechanical properties still show
surprising enhancements over typical commercial copolymers of
comparable molecular weight and composition, particularly in
strength, impact and tear properties.
[0235] Comparative Example C is Dowlex.RTM. 2045, a commercial
ethylene/1-octene copolymer made by The Dow Chemical Company.
Comparative Example D is Dowlex.RTM. 2047, a commercial LLDPE
ethylene/1-octene copolymer made by The Dow Chemical Company.
[0236] The data in Table 6 show that the molecular weight
distribution (M.sub.w/M.sub.n) can surprisingly remain relatively
low, demonstrating a unique feature of the process control of the
invention.
11TABLE 5 Process Conditions for Reactor #1 for Examples 8-14
Overall Monomer Reactor #1 Titanium Volume Temp Reactor #1 H.sub.2
Catalyst #1 Efficiency Ex. (ml) (.degree. C.) (mmol) (micromoles)
(g PE/g Ti) 8 155 158 25 12.5 286100 9 155 146 20 7.5 312400 10 155
156 0 7.5 326600 11 205 155 0 10 311900 12 230 149 0 7.5 312400 13
155 152 0 7.5 305300 14 150 + 150 145 0 7.5 298200
[0237]
12TABLE 5 A Process Conditions for Reactor #2 for Examples 8-14
Overall Monomer Reactor #2 Titanium Volume Temp Reactor #2 H.sub.2
Catalyst #2 Efficiency Ex. (ml) (.degree. C.) (mmol) (micromoles)
(g PE/g Ti) 8 155 190 150 7.2 286100 9 155 170 150 7.2 312400 10
155 188 200 7.2 326600 11 205 194 150 7.2 311900 12 230 194 150 7.2
312400 13 155 196 400 7.2 305300 14 150 + 150 195 150 7.2
298200
[0238]
13TABLE 6 Melt Index Density (I.sub.2) MFR MWD Ex. (g/cm.sup.3)
(g/10 min) (I.sub.10/I.sub.2) M.sub.w M.sub.n (M.sub.w/M.sub.n) C
0.9202 1 ND 110000 27300 4.03 8 0.9257 3.1 6.72 80400 32000 2.5 9
0.9225 1.43 6.89 99400 36800 2.7 10 0.9234 1.57 7.04 100400 35200
2.85 D 0.9171 2.3 ND 85500 22000 3.89 11 0.9158 1.39 7.15 100000
35100 2.85 12 0.916 0.91 7.16 113200 37700 3 13 0.915 0.84 7.94
106900 33300 3.21 14 0.9186 1.09 7.1 106200 36400 2.9 ND = Not
Determined
[0239]
14TABLE 6A Crystal. Melt. Onset Young's Clarity Peak Temp. 2%
Secant Modulus (Specular Haze Ex. (.degree. C.) (.degree. C.)
Modulus (psi) Trans.) (%) C ND 107 29169 29253 3.55 55 8 123 111
48123 48209 0.15 75 9 124 111 47815 47906 0.72 78 10 124 114 34077
34742 0.15 72 D ND ND 26094 26094 1.22 49 11 124 113 26245 26304
0.22 69 12 123 111 35492 35599 0.47 67 13 122 110 26466 26534 1.37
63 14 124 111 34989 35032 0.77 66 ND = Not Determined
[0240]
15TABLE 6B Yield Yield Break Break Toughness Spencer Tensile Ex.
Strength (psi) elongation (%) strength (psi) elongation (%) (ft-lb)
Impact (psi) Tear (g/mil) C 1830 13 4395 689 1292 735 316 8 2628 12
3893 620 1335 992 450 9 2403 13 4375 613 1343 753 367 10 2240 13
3619 600 1179 1043 326 D 1600 15 4061 771 1351 716 285 11 1905 15
5079 700 1480 820 334 12 2043 15 5385 610 1404 976 336 13 1818 21
4504 612 1203 977 247 14 1933 16 4755 653 1332 741 283
[0241] In step (B) of the Second Process, the ethylene and
.alpha.-olefin materials may be present as unreacted materials in
the reaction product from step (A) or they can each be added to the
polymerization reaction mixture in step (B) as needed to make the
desired interpolymer. In addition, hydrogen or other telogen can be
added to the polymerization mixture of step (B) to control
molecular weight.
Examples 15-31 and Comparative Examples E-T
[0242] For the blends of Examples 15-31 and Comparative Examples
E-T the following components were used:
[0243] Homogeneous Interpolymer Blend Components
[0244] Affinity.TM. FM 1570 is a product and registered trademark
of The Dow Chemical Company and has a melt index (I2) of 1.00 g/10
min, an I10/I2 of 10.50 and a density of 0.915 g/cm.sup.3.
[0245] Affinity.TM. PL 1840 is a product and registered trademark
of The Dow Chemical Company and has a melt index (I2) of 1.00 g/10
min, an I10/I2 of 10.00, and a density of 0.909 g/cm.sup.3.
[0246] Affinity.TM. PL 1880 is a product and registered trademark
of The Dow Chemical Company and has a melt index (I2) of 1.00 g/10
min, an I10/I2 of 9.00, and a density of 0.902 g/cm.sup.3.
[0247] Affinity.TM. DPL 1842.00 is a product and registered
trademark of The Dow Chemical Company and has a melt index (I2) of
1.00 g/10 min, an I10/I2 of 10.00, and a density of 0.909
g/cm.sup.3.
[0248] Affinity.TM. EG8100 is a product and registered trademark of
The Dow Chemical Company and has a melt index (I2) of 1.00 g/10
min, an I10/I2 of 7.60, and a density of 0.870 g/cm.sup.3.
[0249] Affinity.TM. VP 8770 is is a product and registered
trademark of The Dow Chemical Company and has a melt index (I2) of
1.00 g/10 min, an I10/I2 of 7.60, and a density of 0.870
g/cm.sup.3.
[0250] Heterogeneous Polymer Blend Components
[0251] Dowlex.TM. 2045 is a product and registered trademark of The
Dow Chemical Company and has a melt index (I2) of 1.00 g/10 min, an
I10/I2 of 8.00 and a density of 0.920 g/cm.sup.3.
[0252] Dowlex.TM. 2027A is a product and registered trademark of
The Dow Chemical Company and has a melt index (I2) of 4.00 g/10
min, an I10/I2 of 6.80 and a density of 0.941 g/cm.sup.3.
[0253] Dowlex.TM. 2038 is a product and registered trademark of The
Dow Chemical Company and has a melt index (I2) of 1.00 g/10 min, an
I10/I2 of 7.40 and a density of 0.935 g/cm.sup.3.
[0254] Dowlex.TM. 2431C is a product and registered trademark of
The Dow Chemical Company and has a melt index (I2) of 7.00 g/10
min, an I10/I2 of 7.00, and a density of 0.935 g/cm.sup.3.
[0255] Dowlex.TM. 2429C is a product and registered trademark of
The Dow Chemical Company and has a melt index (I2) of 4.00 g/10
min, an I10/I2 of 7.40, and a density of 0.935 g/cm.sup.3.
[0256] NG 2429N is a product of The Dow Chemical Company and has a
melt index (I2) of 4.00 g/10 min and a density of 0.935
g/cm.sup.3.
[0257] NG 2431N is a product of The Dow Chemical Company and has a
melt index (I2) of 7.00 g/10 min and a density of 0.935
g/cm.sup.3.
[0258] NG 2432N is a product of The Dow Chemical Company and has a
melt index (I2) of 4.00 g/10 min and a density of 0.939
g/cm.sup.3.
[0259] HDPE 04452N is a product of The Dow Chemical Company and has
a melt index (I2) of 4.00 g/10 min and a density of 0.952
g/cm.sup.3.
[0260] HDPE 05862N is a product of The Dow Chemical Company and has
a melt index (I2) of 5.00 g/10 min and a density of 0.962
g/cm.sup.3.
[0261] HDPE 08454N is a product of The Dow Chemical Company and has
a melt index (I2) of 7.00 g/10 min, an I10/I2 of 7.40, and a
density of 0.954 g/cm.sup.3.
[0262] For the blend compositions in Tables 9-12, typically after
Components A and B are initially selected, then the additional
Component(s) C (and sometimes D) if required, are selected to
achieve the target final blend melt index and density. First the
components of each blend were tumble blended for sufficient time to
insure a homogeneous distribution of the components. The dry blends
were subsequently melt blended. The following Examples and
Comparative Examples from Tables 9 and 11 were melt blend
compounded on a 1.5" NRM, single screw extruder: Example 15,
Example 17, Example 18, Example 19, Example 21, Example 23, Example
25, Example 26, Example 27, Example 29, Example 30, Comparative E,
Comparative F, Comparative S and Comparative T. The Set Point
conditions for the NRM are listed below in Table 7. The output rate
was approximately 70-100 pounds/hour and the melt temperature was
381 F.
16TABLE 7 Set Point Conditions for 1.5" NRM, Single Screw Extruder
Feeder 365.degree. F. Zone 1 .degree. C. 365.degree. F. Zone 2
365.degree. F. Zone 3 365.degree. F. Zone 4 365.degree. F. Zone 5
365.degree. F. Zone 6 365.degree. F. Zone 7 365.degree. F. Die
Temperature 365.degree. F. Screw Speed 65 RPM Melt Temperature
(Actual) 338.degree. F.
[0263] The remainder of the Examples and Comparative Examples in
Tables 9 and 11 were melt blend compounded on a Haake Rheocord
300p/Rheomex PTW25p 25 mm twin screw extruder. The Set Point
conditions for the Haake twin screw extruder are listed below in
Table 8. The output rate was approximately 10 pounds/hour and the
melt temperature was 338 F.
17TABLE 8 Set Point Conditions for 1.5" NRM, Single Screw Extruder
Barrel Zone 1 275.degree. F. Barrel Zone 2 325.degree. F. Barrel
Zone 3 350.degree. F. Barrel Zone 4 350.degree. F. Die Zone 3
350.degree. F. Die Zone 2 350.degree. F. Die Zone 1 350.degree. F.
Screw Speed 50 RPM Die Temperature 350.degree. F. Melt Temperature
381.degree. F.
[0264] The various blend compositions and properties are summarized
in Table 9 to 12.
18TABLE 9 Description Example 15 Example 16 Example 17 Example 18
Example 19 Example 20 Resin A EG 8100 VP 8770 PL 1880 EG 8100 VP
8770 PL 1880 Wt % A 0.1500 0.1500 0.1500 0.1500 0.2000 0.1890
Density A 0.8700 0.8850 0.9020 0.8700 0.8850 0.9020 I2 A 1.00 1.00
1.00 1.00 1.00 1.00 Volume Fraction A 0.1613 0.1586 0.1554 0.1618
0.2127 0.1973 Resin B HDPE 08454N Dowlex 2429C Dowlex 2429C Dowlex
2038 Dowlex 2038 Dowlex 2038 Wt % B 0.0851 0.0372 0.1872 0.2669
0.2224 0.1501 Density B 0.9540 0.9350 0.9350 0.9350 0.9350 0.9350
I2 B 7.00 4.00 4.00 1.00 1.00 1.00 Resin C Dowlex 2431C Dowlex
2431C Dowlex 2431C HDPE 04452N HDPE 04452N HDPE 04452N Wt % C
0.2865 0.3716 0.3716 0.0995 0.0594 0.6610 Density C 0.9350 0.9350
0.9350 0.9520 0.9520 0.9520 I2 C 7.00 7.00 7.00 4.00 4.00 4.00
Resin D HDPE 04452N HDPE 04452N HDPE 04452N HDPE 05862N HDPE 05862N
Wt % D 0.4784 0.4412 0.2912 0.4836 0.5181 Density D 0.9520 0.9520
0.9520 0.9620 0.9620 I2 D 4.0000 4.0000 4.0000 5.0000 5.0000 Final
Density 0.9356 0.9357 0.9346 0.9387 0.9410 0.9419 Final I2 3.42
3.89 3.97 2.30 2.54 2.62 Final I10/I2 8.50 7.51 7.43 7.91 7.45 7.20
Description Example 21 Example 22 Example 23 Example 24 Example 25
Example 26 Resin A EG 8100 PL 1880 VP 8770 PL 1880 EG 8100 VP 8770
Wt % A 0.2066 0.2075 0.2075 0.1498 0.0963 0.1791 Density A 0.8700
0.9020 0.8850 0.9020 0.8700 0.8850 I2 A 1.00 1.00 1.00 1.00 1.00
1.00 Volume Fraction A 0.2232 0.2165 0.2201 0.1563 0.1041 0.1907
Resin B Dowlex 2038 Dowlex 2027A Dowlex 2038 Dowlex 2027A Dowlex
2027A HDPE 04452N Wt % B 0.1108 0.1476 0.0422 0.4101 0.3697 0.8209
Density B 0.9350 0.9410 0.9350 0.9410 0.9410 0.9520 I2 B 1.00 4.00
1.00 4.00 4.00 4.00 Resin C HDPE 05862N HDPE 04452N HDPE 04452N
HDPE 04452N HDPE 04452N Wt % C 0.6826 0.6448 0.4883 0.4401 0.5340
Density C 0.9620 0.9520 0.9520 0.9520 0.9520 I2 C 5.00 4.00 4.00
4.00 4.00 Resin D HDPE 05862N Wt % D 0.2620 Density D 0.9620 I2 D
5.0000 Final Density 0.9396 0.9408 0.9387 0.9413 0.9406 0.9425
Final I2 3.07 3.15 3.30 3.30 3.77 3.45 Final I10/I2 7.50 7.06 7.22
7.00 6.99 7.44 Description Example 27 Example 28 Example 29 Example
30 Example 31 Resin A VP 8770 PL 1880 EG 8100 VP 8770 PL 1880 Wt %
A 0.0963 0.0963 0.1192 0.1192 0.1192 Density A 0.8850 0.9020 0.8700
0.8850 0.9020 I2 A 1.00 1.00 1.00 1.00 1.00 Volume Fraction A
0.1024 0.0999 0.1302 0.1280 0.1255 Resin B Dowlex 2027A Dowlex
2027A HDPE 04452N HDPE 04452N HDPE 04452N Wt % B 0.5012 0.6531
0.1406 0.2513 0.3769 Density B 0.9410 0.9410 0.9520 0.9520 0.9520
I2 B 4.00 4.00 4.00 4.00 4.00 Resin C HDPE 04452N HDPE 04452N HDPE
05862N HDPE 08454N HDPE 08454N Wt % C 0.4025 0.2506 0.7402 0.0735
0.1568 Density C 0.9520 0.9520 0.9625 0.9540 0.9540 I2 C 4.00 4.00
5.00 7.00 7.00 Resin D HDPE 05862N HDPE 05862N Wt % D 0.5560 0.3472
Density D 0.9625 0.9625 I2 D 5.0000 5.0000 Final Density 0.9413
0.9408 0.9504 0.9502 0.9499 Final I2 3.70 3.63 4.27 4.30 4.15 Final
I10/I2 6.90 6.87 7.27 7.29 7.49
[0265]
19TABLE 10 Description Example 15 Example 16 Example 17 Example 18
Example 19 Example 20 Density 0.9356 0.9357 0.9346 0.9387 0.9410
0.9419 I2 3.42 3.89 3.97 2.30 2.54 2.62 I10/I2 8.50 7.51 7.43 7.91
7.45 7.20 1% Sec Modulus (psi) 75500 77134 75593 101953 112178 2%
Sec Modulus (psi) 63171 64550 63260 85760 93944 101673 Flex Modulus
(psi) 93864 97589 97220 118274 133755 133488 Yield (psi) 2335 2300
2233 2544 2660 2790 Ultimate (psi) 3841 3544 3855 4404 4448 4368 %
Elongation 989 918 886 947 959 999 Energy to Break (In-Lb) 384 340
342 393 407 Vicat (.degree. C.) 116 117 117 119 119 122 Heat
Distortion 54.1 54.6 52.5 57.4 58.0 55.5 Izod Impact RT (ft.
lbs./in.) 9.9 8.9 8.1 10.9 12.6 11.2 Izod Impact 0 (ft. lbs./in.)
7.2 7.8 4.3 9.9 11.2 10.5 Izod Impact -20 (ft. lbs./in.) 6.6 1.8
1.6 9.9 10.9 1.9 Izod Impact -40 (ft. lbs./in.) 1.5 1.4 Description
Example 21 Example 22 Example 23 Example 24 Example 25 Example 26
Density 0.9396 0.9408 0.9387 0.9413 0.9406 0.9425 I2 3.07 3.15 3.30
3.30 3.77 3.45 I10/I2 7.50 7.06 7.22 7.00 6.99 7.44 1% Sec Modulus
(psi) 109073 112009 103374 115285 2% Sec Modulus (psi) 90851 100353
93753 96752 86119 95746 Flex Modulus (psi) 130763 130694 134287
127737 124082 140036 Yield (psi) 2688 2520 2652 2726 2716 2696
Ultimate (psi) 3751 4256 4310 4143 4159 4401 % Elongation 987 999
1036 1001 1076 932 Energy to Break (In-Lb) 393 451 459 412 Vicat
(.degree. C.) 111 121 118 121 124 122 Heat Distortion 55.4 57.6
55.9 53.2 56.0 59.3 Izod Impact RT (ft. lbs./in.) 11.8 11.1 9.5
10.9 11.0 9.8 Izod Impact 0 (ft. lbs./in.) 10.7 11.0 9.2 9.0 6.6
6.9 Izod Impact -20 (ft. lbs./in.) 10.5 2.0 7.7 2.0 1.8 4.1 Izod
Impact -40 (ft. lbs./in.) 1.9 1.1 1.6 1.5 1.2 Description Example
27 Example 28 Example 29 Example 30 Example 31 Density 0.9413
0.9408 0.9504 0.9502 0.9499 I2 3.70 3.63 4.27 4.30 4.15 I10/I2 6.90
6.87 7.27 7.29 7.49 1% Sec Modulus (psi) 101365 135968 121543
117812 2% Sec Modulus (psi) 84446 99865 112473 100691 97297 Flex
Modulus (psi) 124659 131207 162608 151304 147838 Yield (psi) 2591
2775 3244 3262 3113 Ultimate (psi) 4364 3886 3604 3823 3849 %
Elongation 1233 977 1227 1124 1162 Energy to Break (In-Lb) 555 524
480 509 Vicat (.degree. C.) 123 121 123 128 128 Heat Distortion
56.2 58.4 61.1 66.9 64.6 Izod Impact RT (ft. lbs./in.) 9.8 9.5 10.5
8.9 3.8 Izod Impact 0 (ft. lbs./in.) 2.5 2.5 6.1 2.5 1.3 Izod
Impact -20 (ft. lbs./in.) 1.5 1.8 1.4 1.3 1.2 Izod Impact -40 (ft.
lbs./in.) 1.7
[0266]
20TABLE 11 Description Comparative E Comparative F Comparative G
Comparative H Comparative I Comparative J Resin A PL 1840 FM 1570
DPL 1842.00 FM 1570 Dowlex 2045 Dowlex 2045 Wt % A 0.1500 0.1500
0.2399 0.3118 0.3390 0.3390 Density A 0.909 0.915 0.909 0.915 0.92
0.92 I2 A 1.0 1.0 1.0 1.0 1.0 1.0 Volume Fraction A 0.1543 0.1533
0.2471 0.3198 0.3455 0.3467 Resin B Dowlex 2429C Dowlex 2429C
Dowlex 2038 Dowlex 2038 NG 2432N NG 2429N Wt % B 0.2490 0.3019
0.0992 0.0272 0.0885 0.0677 Density B 0.935 0.935 0.935 0.935 0.939
0.935 I2 B 4.0 4.0 1.0 1.0 4.0 4.0 Resin C Dowlex 2431C Dowlex
2431C HDPE 04452N HDPE 04452N HDPE 04452N HDPE 04452N Wt % C 0.3716
0.3716 0.6610 0.6610 0.5724 0.5933 Density C 0.935 0.935 0.952
0.952 0.952 0.952 I2 C 7.0 7.0 4.0 4.0 4.0 4.0 Resin D HDPE 04452N
HDPE 04452N Wt % D 0.2294 0.1765 Density D 0.952 0.952 I2 D 4.0 4.0
Final Density 0.9352 0.9349 0.9365 0.9384 0.9375 0.9408 Final I2
4.03 4.02 2.62 2.59 2.15 2.58 Final I10/I2 7.4 7.4 7.3 7.6 7.5 6.9
Description Comparative K Comparative L Comparative M Comparative N
Comparative 0 Comparative P Resin A DPL 1842.00 FM 1570 Dowlex 2045
DPL 1842.00 FM1570 DPL 1842.00 Wt % A 0.2075 0.2075 0.2075 0.1498
0.1498 0.0963 Density A 0.909 0.915 0.92 0.909 0.915 0.909 I2 A 1.0
1.0 1.0 1.0 1.0 1.0 Volume Fraction A 0.2149 0.2133 0.2122 0.1551
0.1541 0.0993 Resin B Dowlex 2027A Dowlex 2027A NG 2429N Dowlex
2027A Dowlex 2027A Dowlex 2027A Wt % B 0.2797 0.3929 0.3153 0.5054
0.5871 0.7144 Density B 0.941 0.941 0.935 0.941 0.941 0.941 I2 B
4.0 4.0 4.0 4.0 4.0 4.0 Resin C HDPE 04452N HDPE 04452N HDPE 04452N
HDPE 04452N HDPE 04452N HDPE 04452N Wt % C 0.5128 0.3996 0.4772
0.3448 0.2631 0.1893 Density C 0.952 0.952 0.952 0.952 0.952 0.952
I2 C 4.0 4.0 4.0 4.0 4.0 4.0 Final Density 0.9415 0.9406 0.9408
0.9412 0.9415 0.9410 Final 12 3.04 3.09 2.97 3.39 3.38 3.60 Final
I10/I2 7.2 7.2 7.1 7.1 7.0 6.8 Description Comparative Q
Comparative R Comparative S Comparative T Resin A FM1570 Dowlex
2045 PL 1840 FM1570 Wt % A 0.0963 0.2075 0.1192 0.1192 Density A
0.915 0.92 0.909 0.915 I2 A 1.0 1.0 1.0 1.0 Volume Fraction A
0.0991 0.2119 0.1247 0.1238 Resin B Dowlex 2027A NG2431N HDPE
04452N HDPE 04452N Wt % B 0.7669 0.4123 0.4286 0.4729 Density B
0.941 0.935 0.952 0.952 I2 B 4.0 7.0 4.0 4.0 Resin C HDPE 04452N
HDPE 04452N HDPE 08454N HDPE 08454N Wt % C 0.1368 0.3802 0.1911
0.2205 Density C 0.952 0.952 0.954 0.954 I2 C 4.0 4.0 7.0 7.0 Resin
D HDPE 05862N HDPE 05862N Wt % D 0.2611 0.1875 Density D 0.9625
0.9625 I2 D 5.0 5.0 Final Density 0.9410 0.9394 0.9509 0.9506 Final
I2 3.63 3.73 3.70 4.47 Final I10/I2 7.0 7.1 8.3 7.3
[0267]
21TABLE 12 Comparative Comparative Comparative Comparative
Comparative Comparative Comparative Comparative Description E F G H
I J K L Density 0.9352 0.9349 0.9365 0.9384 0.9375 0.9408 0.9415
0.9406 I2 4.03 4.02 2.62 2.59 2.15 2.58 3.04 3.09 I10/I2 7.42 7.41
7.34 7.57 7.54 6.94 7.23 7.23 1% Sec Modulus (psi) 72971 76995 2%
Sec Modulus (psi) 61335 64186 81563 88222 82578 95217 98803 98230
Flex Modulus (psi) 92740 100596 103989 114934 106039 125597 126879
130327 Yield (psi) 2312 2300 2481 2548 2410 2800 2827 2802 Ultimate
(psi) 3770 3723 4414 4068 4311 4356 4164 4130 % Elongation 966 1119
987 994 1000 998 999 996 Energy to Break (In-Lb) 376 447 Vicat
(.degree. C.) 116 117 118 118 117 121 120 120 Heat Distortion 51.5
49.9 52.1 53.8 52.4 56.7 55.6 55.1 Izod Impact RT (ft. lbs./in.)
8.7 6.4 11.6 10.2 11.6 9.2 8.9 8.2 Izod Impact 0 (ft. lbs./in.) 2.1
1.5 3.8 3.5 4.8 2.7 2.7 2.2 Izod Impact -20 (ft. lbs./in.) 1.4 1.3
1.7 1.8 1.8 1.6 1.8 1.7 Izod Impact -40 (ft. lbs./in.) 1.6 1.6 1.5
1.6 1.4 1.6 Comparative Comparative Comparative Comparative
Comparative Comparative Comparative Comparative Description M N O P
Q R S T Density 0.9408 0.9412 0.9415 0.9410 0.9410 0.9394 0.9509
0.9506 I2 2.97 3.39 3.38 3.60 3.63 3.73 3.70 4.47 I10/I2 7.14 7.06
7.02 6.77 6.97 7.12 8.25 7.34 1% Sec Modulus (psi) 117446 127849 2%
Sec Modulus (psi) 96379 108823 99322 101133 93929 91831 96957
105429 Flex Modulus (psi) 125865 149601 133536 136044 123224 120391
152326 161894 Yield (psi) 2758 2832 2784 2733 2745 2617 3462 3374
Ultimate (psi) 4190 4098 4022 4123 3894 4109 3879 3912 % Elongation
999 1001 1000 1008 1004 999 1214 1351 Energy to Break (In-Lb) 511
574 Vicat (.degree. C.) 120 121 121 121 121 119 128 128 Heat
Distortion 56.4 56.6 59.4 55.5 60.2 56.1 68.0 67.6 Izod Impact RT
(ft. lbs./in.) 7.1 5.5 5.4 3.9 3.5 3.9 1.8 1.4 Izod Impact 0 (ft.
lbs./in.) 2.1 1.9 1.8 2.1 2.0 1.8 1.2 1.2 Izod Impact -20 (ft.
lbs./in.) 1.6 1.7 1.7 1.7 1.6 1.5 1.2 1.1 Izod Impact -40 (ft.
lbs./in.) 1.5 1.7 1.7 1.6 1.7 1.5
[0268] The data in Tables 9-12 and FIG. 1 demonstrate the
surprising step change increase in Izod impact, measured at either
23.degree. C., 0.degree. C. or -20.degree. C., when the density of
Component A is less than 0.909 g/cm.sup.3.
* * * * *