U.S. patent application number 13/006057 was filed with the patent office on 2012-02-02 for viscosity modifiers comprising blends of ethylene-based copolymers.
Invention is credited to Sudhin DATTA, Liehpao O. Farng, Rainer Kolb, Vera Minak-Bernero, Eric B. Sirota, Diana Smirnova, Mun F. Tse.
Application Number | 20120028866 13/006057 |
Document ID | / |
Family ID | 45527317 |
Filed Date | 2012-02-02 |
United States Patent
Application |
20120028866 |
Kind Code |
A1 |
DATTA; Sudhin ; et
al. |
February 2, 2012 |
Viscosity Modifiers Comprising Blends of Ethylene-Based
Copolymers
Abstract
The present invention is directed to polymer blend compositions
for use as viscosity modifiers comprising at least two
ethylene-based copolymer components. The viscosity modifiers
described herein comprise a first ethylene-based copolymer having
an ethylene content of from about 44 to about 52 wt % and/or a heat
of fusion of from about 0 to about 15 J/g and a second
ethylene-based copolymer having an ethylene content of from about
68 to about 75 wt % and/or a heat of fusion of from about 40 to
about 65 J/g. The invention is also directed to lubricant
compositions comprising a lubricating basestock and a polymer blend
of the invention.
Inventors: |
DATTA; Sudhin; (Houston,
TX) ; Farng; Liehpao O.; (Lawrenceville, NJ) ;
Minak-Bernero; Vera; (Bridgewater, NJ) ; Tse; Mun
F.; (Seabrook, TX) ; Sirota; Eric B.;
(Flemington, NJ) ; Smirnova; Diana; (High Bridge,
NJ) ; Kolb; Rainer; (Kingwood, TX) |
Family ID: |
45527317 |
Appl. No.: |
13/006057 |
Filed: |
January 13, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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61368473 |
Jul 28, 2010 |
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Current U.S.
Class: |
508/591 ;
525/240 |
Current CPC
Class: |
C08L 2205/025 20130101;
C10N 2030/68 20200501; C10M 2219/046 20130101; C08L 2205/03
20130101; C10M 2205/022 20130101; C10M 107/04 20130101; C10M
2203/1025 20130101; C10N 2030/02 20130101; C10M 169/047 20130101;
C08L 23/16 20130101; C10N 2030/74 20200501; C10M 107/06 20130101;
C08L 23/0815 20130101; C08L 23/08 20130101; C08L 23/0815 20130101;
C08L 23/0815 20130101; C08L 23/0815 20130101; C08L 2205/025
20130101; C08L 2205/03 20130101; C08L 23/16 20130101; C08L 23/16
20130101; C08L 23/16 20130101; C08L 2205/025 20130101; C08L 2205/03
20130101; C10M 2205/022 20130101; C10M 2205/022 20130101; C10M
2205/022 20130101; C10M 2205/022 20130101; C10M 2205/024 20130101;
C10M 2205/022 20130101; C10N 2020/04 20130101; C10M 2219/046
20130101; C10N 2010/04 20130101; C10M 2205/022 20130101; C10N
2020/04 20130101; C10M 2219/046 20130101; C10N 2010/04
20130101 |
Class at
Publication: |
508/591 ;
525/240 |
International
Class: |
C10M 143/02 20060101
C10M143/02; C08L 23/04 20060101 C08L023/04 |
Claims
1. A polymer blend composition comprising a first ethylene-based
copolymer and a second ethylene-based copolymer, wherein: (a) the
first copolymer has an ethylene content from about 44 to about 52
wt %; (b) the second copolymer has an ethylene content from about
68 to about 75 wt %; (c) the first and second copolymers have a
weight-average molecular weight (Mw) less than or equal to about
130,000; (d) the ratio of the melt index of the first copolymer to
the melt index of the second copolymer is less than or equal to
about 3.0; and (e) the composition comprises from about 35 to about
65 wt % of the first copolymer, based on the total weight of the
first and second copolymers.
2. The polymer blend composition of claim 1, wherein the first
copolymer has an ethylene content from about 45 to about 51 wt %
and the second copolymer has an ethylene content from about 69 to
about 74 wt %.
3. The polymer blend composition of claim 2, wherein the first
copolymer has an ethylene content from about 46 to about 50 wt %,
and the second copolymer has an ethylene content from about 70 to
about 73 wt %.
4. The polymer blend composition of claim 1, wherein the first and
second copolymers each comprise one or more comonomers selected
from the group consisting of C.sub.3-C.sub.20 alpha-olefins.
5. The polymer blend composition of claim 1, wherein the ethylene
content of the second copolymer is at least about 17 wt % greater
than the ethylene content of the first copolymer.
6. The polymer blend composition of claim 5, wherein the ethylene
content of the second copolymer is at least about 21 wt % greater
than the ethylene content of the first copolymer.
7. The polymer blend composition of claim 1, wherein the
composition comprises from about 38 to about 62 wt % of the first
copolymer, based on the total weight of the first and second
copolymers.
8. The polymer blend composition of claim 7, wherein the
composition comprises from about 40 to about 60 wt % of the first
copolymer, based on the total weight of the first and second
copolymers.
9. A polymer blend composition comprising a first ethylene-based
copolymer and a second ethylene-based copolymer, wherein: (a) the
first copolymer has a heat of fusion from about 0 to about 15 J/g;
(b) the second copolymer has a heat of fusion from about 40 to
about 65 J/g; (c) the first and second copolymers have a
weight-average molecular weight (Mw) less than or equal to about
130,000; (d) the ratio of the melt index of the first copolymer to
the melt index of the second copolymer is less than or equal to
about 3.0; and (e) the composition comprises from about 35 to about
65 wt % of the first copolymer, based on the total weight of the
first and second copolymers.
10. The polymer blend composition of claim 9, wherein the first
copolymer has a heat of fusion from about 0 to about 10 J/g and the
second copolymer has a heat of fusion from about 42 to about 62
J/g.
11. The polymer blend composition of claim 10, wherein the first
copolymer has a heat of fusion from about 0 to about 5 J/g and the
second copolymer has a heat of fusion from about 45 to about 60
J/g.
12. The polymer blend composition of claim 9, wherein the first and
second copolymers each comprises one or more comonomers selected
from the group consisting of C.sub.3-C.sub.20 alpha-olefins.
13. The polymer blend composition of claim 9, wherein the ethylene
content of the second copolymer is at least about 17 wt % greater
than the ethylene content of the first copolymer.
14. The polymer blend composition of claim 13, wherein the ethylene
content of the second copolymer is at least about 21 wt % greater
than the ethylene content of the first copolymer.
15. The polymer blend composition of claim 9, wherein the
composition comprises from about 38 to about 62 wt % of the first
copolymer, based on the total weight of the first and second
copolymers.
16. The polymer blend composition of claim 15, wherein the
composition comprises from about 40 to about 60 wt % of the first
copolymer, based on the total weight of the first and second
copolymers.
17. A lubricating oil composition comprising a lubricating oil
basestock, a first ethylene-based copolymer, and a second
ethylene-based copolymer, wherein: (a) the first copolymer has an
ethylene content from about 44 to about 52 wt %; (b) the second
copolymer has an ethylene content from about 68 to about 75 wt %;
(c) the first and second copolymers have a weight-average molecular
weight (Mw) less than or equal to about 130,000; (d) the ratio of
the melt index of the first copolymer to the melt index of the
second copolymer is less than or equal to about 3.0; and (e) the
composition comprises from about 35 to about 65 wt % of the first
copolymer, based on the total weight of the first and second
copolymers.
18. The lubricating oil composition of claim 17, wherein the first
copolymer has an ethylene content from about 46 to about 50 wt %,
and the second copolymer has an ethylene content from about 70 to
about 73 wt %.
19. The lubricating oil composition of claim 17, wherein the first
and second copolymers each comprise one or more comonomers selected
from the group consisting of C.sub.3-C.sub.20 alpha-olefins.
20. The lubricating oil composition of claim 17, wherein the
ethylene content of the second copolymer is at least about 21 wt %
greater than the ethylene content of the first copolymer.
21. A lubricating oil composition comprising a lubricating oil
basestock, a first ethylene-based copolymer, and a second
ethylene-based copolymer, wherein: (a) the first copolymer has a
heat of fusion from about 0 to about 15 J/g; (b) the second
copolymer has a heat of fusion from about 40 to about 65 J/g; (c)
the first and second copolymers have a weight-average molecular
weight (Mw) less than or equal to about 130,000; (d) the ratio of
the melt index of the first copolymer to the melt index of the
second copolymer is less than or equal to about 3.0; and (e) the
composition comprises from about 35 to about 65 wt % of the first
copolymer, based on the total weight of the first and second
copolymers.
22. The lubricating oil composition of claim 21, wherein the first
copolymer has a heat of fusion from about 0 to about 5 J/g and the
second copolymer has a heat of fusion from about 45 to about 60
J/g.
23. The lubricating oil composition of claim 21, wherein the first
and second copolymers each comprise one or more comonomers selected
from the group consisting of C.sub.3-C.sub.20 alpha-olefins.
24. The lubricating oil composition of claim 21, wherein the
ethylene content of the second copolymer is at least about 21 wt %
greater than the ethylene content of the first copolymer.
Description
PRIORITY CLAIM
[0001] This application claims the benefit of and priority to U.S.
Patent Application Ser. No. 61/368,473, entitled "Discrete
Ethylene-Based Copolymers as Viscosity Modifiers" and filed Jul.
28, 2010, which is incorporated by reference herein in its
entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to polymer blends useful as
rheology modifiers. More particularly, the invention relates to
compositionally disperse and/or crystallinity disperse polymer
blends that are useful in modifying the rheological properties of
fluids, wherein the individual components of the polymer blend have
large differences in crystallinity and include at least one
component having no observable crystallinity.
BACKGROUND OF THE INVENTION
[0003] Lubrication fluids are applied between moving surfaces to
reduce friction, thereby improving efficiency and reducing wear.
Lubrication fluids also often function to dissipate the heat
generated by moving surfaces.
[0004] One type of lubrication fluid is a petroleum-based
lubrication oil used for internal combustion engines. Lubrication
oils contain additives that help the lubrication oil to have a
certain viscosity at a given temperature. In general, the viscosity
of lubrication oils and fluids is inversely dependent upon
temperature. When the temperature of a lubrication fluid is
increased, the viscosity generally decreases, and when the
temperature is decreased, the viscosity generally increases. For
internal combustion engines, for example, it is desirable to have a
lower viscosity at low temperatures to facilitate engine starting
during cold weather, and a higher viscosity at higher ambient
temperatures when lubrication properties typically decline.
[0005] Additives for lubrication fluids and oils include rheology
modifiers, such as viscosity index (VI) improvers. VI improving
components, many of which are derived from ethylene-alpha-olefin
copolymers, modify the rheological behavior of a lubricant to
increase viscosity and promote a more constant viscosity over the
range of temperatures at which the lubricant is used. Higher
ethylene content copolymers efficiently promote oil thickening and
shear stability. However, higher ethylene content copolymers also
tend to flocculate or aggregate in oil formulations leading to
extremely viscous and, in the limit, solid formulations.
Flocculation typically happens at ambient or subambient conditions
of controlled and quiescent cooling. This deleterious property of
otherwise advantageous higher ethylene content viscosity improvers
is measured by low temperature solution rheology. Various remedies
have been proposed for these higher ethylene content copolymer
formulations to overcome or mitigate the propensity towards the
formation of high viscosity flocculated materials.
[0006] It is anticipated that the performance of VI improvers can
be substantially improved, as measured by the thickening efficiency
(TE) and the shear stability index (SSI), by appropriate and
careful manipulation of the structure of the VI improver.
Particularly, it has been discovered that performance improves when
the distribution of the monomers and the chain architecture are
controlled and segregated into at least three compositionally
disperse and/or crystallinity disperse polymeric populations. These
disperse polymeric populations may be achieved by the use of a
synthesis process that employs metallocene-based catalysts in the
polymerization process.
[0007] One proposed solution is the use of blends of amorphous and
semi-crystalline ethylene-based copolymers for lubricant oil
formulations. The combination of two such ethylene-propylene
copolymers allows for increased thickening efficiency, shear
stability index, low temperature viscosity performance and pour
point. See, e.g., U.S. Pat. Nos. 7,402,235 and 5,391,617, and
European Patent 0 638,611, the disclosures of which are
incorporated herein by reference.
[0008] There remains a need, however, for novel rheology modifier
compositions comprised of ethylene and alpha-olefin-based
comonomers suitable for use in VI improvers which have unexpectedly
high thickening efficiency compared to prior compositions while
still being equivalent in their beneficial low temperature solution
rheology properties. The present invention meets this and other
needs. The combined components of the invention deliver a viscosity
modifier which does not show an adverse effect on viscosity due to
lowering the temperature from ambient to -35.degree. C. in solution
in synthetic and petroleum basestocks.
[0009] Contrary to the teachings of the prior art, it has been
found that there is a preferred relationship between the amount and
composition of the discrete distributions of the ethylene-based
alpha-olefin copolymers used in the polymeric blends for VI
improvers. This relationship leads to ethylene-based alpha-olefin
copolymers having a distribution of at least two individual
ethylene-based copolymers with C.sub.3-C.sub.20 alpha olefin
comonomers. Each of the individual ethylene-based copolymers
(hereinafter components) is a single copolymer made in a single
polymerization environment having a predefined composition and
molecular weight. In one or more embodiments, each of the
components is a most probable distribution of molecular weights.
The components differ in their molecular weight and composition.
The invention describes the combination of these polymers in a
predetermined weight ratio such that the less crystalline polymer
(typically one with a lower wt % ethylene in the composition of the
component) is present in an amount of from about 35 to about 65 wt
% based on the total weight of the combination. The balance of the
composition is a component with greater crystallinity and thus a
higher wt % ethylene. It is preferred if the less crystalline
polymer comprises from about 38 to about 62 wt %, or from about 40
to about 60 wt % of the weight of the entire viscosity
modifier.
[0010] The present invention describes the ranges of the
composition and crystallinity for the components of the viscosity
modifier. In some embodiments of the invention, the components,
when they are copolymers of ethylene and propylene, are separated
by no less than 17 wt % and preferably no less than 21 wt %
ethylene content. In addition, the less crystalline polymer has an
ethylene content from about 44 to about 52 wt % and preferably from
about 46 to about 50 wt %.
SUMMARY OF THE INVENTION
[0011] The present invention is directed to polymer blend
compositions for use as viscosity modifiers comprising at least two
ethylene-based copolymer components. The viscosity modifiers
described herein comprise a first ethylene-based copolymer having
an ethylene content of from about 44 to about 52 wt % and/or a heat
of fusion of from about 0 to about 30 J/g and a second
ethylene-based copolymer having an ethylene content of from about
68 to about 75 wt % and/or a heat of fusion of from about 30 to
about 50 J/g. The invention is also directed to lubricant
compositions comprising a lubricating basestock and a polymer blend
as described herein.
DETAILED DESCRIPTION OF THE INVENTION
[0012] The present invention relates to polymer blends comprising
polymer components including, but not limited to, compositionally
disperse ethylene-based copolymers and/or crystallinity disperse
ethylene-based copolymers that are useful in modifying the
rheological properties of lubrication fluids. The compositionally
disperse polymer blends are formed from at least two discrete
compositions of ethylene-based copolymers. The crystallinity
disperse polymer blends are formed from ethylene-based copolymers
having at least two discrete values of residual crystallinity.
[0013] The performance of ethylene-based rheology modifiers as
viscosity index (VI) improvers is measured by the thickening
efficiency (TE) and the shear stability index (SSI), particularly
by the ratio of TE to SSI. It is generally believed that the
composition of an olefin copolymer at a given SSI largely
determines the TE, and that higher ethylene content is preferred
because of its inherent higher TE. While increasing the ethylene
content of rheology modifiers leads to improved TE/SSI ratios, it
also leads to increasing crystallinity of the olefin copolymer.
Increasing crystallinity, however, detracts from the performance of
a rheology modifier as a VI improver because crystalline polymers
tend to flocculate, either by themselves or in association with
other components of the lubrication oil, and precipitate out of
lubrication oils. These precipitates are apparent as regions (e.g.,
"lumps") of high viscosity or essentially complete solidification
(e.g., "gels") and can lead to clogs and blockages of pumps and
other passageways for the lubrication fluid and can harm and in
some cases cause failure of moving machinery.
[0014] While not wishing to be bound by any particular theory, it
is believed that rheology modifiers for lubrication fluids
comprising ethylene-based copolymers which are compositionally
disperse and/or crystallinity disperse will be less prone to the
deleterious effects of macroscopic crystallization in dilute
solution, as measured by the change in the rheology of the fluid
solution compared to an equivalent amount of a single
ethylene-based copolymer of the same average composition as the
disperse blend. It is also believed that these compositionally
and/or crystallinity disperse components will have lower
crystallization on cooling from ambient to sub-ambient
temperatures, resulting in better low temperature flow properties
in solution as compared to equivalent compositionally uniform
polymers of similar molecular weight and thickening efficiency.
These polymer blends and their use in lubrication oil compositions
with basestocks can be distinguished from other compositionally
non-disperse olefin copolymers by physical separation of the
compositionally disperse polymer blend into components as well as
by a higher ratio of the melting point by DSC to the heat of fusion
than would be observed for a non-disperse polymer of the same
average ethylene content, melt viscosity, and composition.
[0015] This invention is directed to a selection of blend
compositions for use as viscosity modifiers comprising at least two
ethylene-based copolymer components. The viscosity modifiers
described herein comprise a first ethylene-based copolymer having
an ethylene content from about 44 to about 52 wt % and/or a heat of
fusion of from about 0 to about 15 J/g and a second ethylene-based
copolymer having an ethylene content of from about 68 to about 75
wt % and/or a heat of fusion of from about 40 to about 65 J/g. The
copolymers each have a weight average molecular weight (Mw) less
than or equal to about 130,000, and MIA/MIB is less than or equal
to about 3.0. The invention is also directed to lubricant
compositions comprising a lubricating basestock and a polymer blend
as described herein.
DEFINITIONS
[0016] For purposes of this invention and the claims herein, the
definitions set forth below are used.
[0017] As used herein, the term "complex viscosity" means a
frequency-dependent viscosity function determined during forced
small amplitude harmonic oscillation of shear stress, in units of
Pascal-seconds, that is equal to the difference between the dynamic
viscosity and the out-of-phase viscosity (imaginary part of complex
viscosity).
[0018] As used herein, the term "Composition Distribution Breadth
Index" (CDBI) is as defined in U.S. Pat. No. 5,382,630, which is
incorporated by reference herein. CDBI is defined as the weight
percent of the copolymer molecules having a comonomer content
within 50% of the median total molar comonomer content. The CDBI of
a copolymer is readily determined utilizing well known techniques
for isolating individual fractions of a sample of the copolymer.
One such technique is Temperature Rising Elution Fraction (TREF),
as described in L. Wild, et al., J. Poly. Sci., Poly. Phys. Ed.,
vol. 20, p. 441 (1982) and U.S. Pat. No. 5,008,204, both of which
are incorporated herein by reference.
[0019] As used herein, the term "compositionally disperse" means a
polymer blend comprised of at least three discrete compositions of
ethylene-based copolymers.
[0020] As used herein, the term "copolymer" includes any polymer
having two or more monomers.
[0021] As used herein, the term "crystallinity disperse" means a
polymer blend comprised of at least three ethylene-based copolymers
having discrete values of residual crystallinity.
[0022] As used herein, the term "disperse" means that the
compositions include constituent polymer fractions which have
different compositions and/or different crystallinity due, in part,
to different molecular weight distributions and/or different
monomer compositional or sequence distributions.
[0023] As used herein, the term "EA" means the weight percent of
ethylene-derived units in the first ethylene-based copolymer based
on the weight of the first ethylene-based copolymer.
[0024] As used herein, the term "EB" means the weight percent of
ethylene-derived units in the second ethylene-based copolymer based
on the weight of the second ethylene-based copolymer.
[0025] As used herein, the term "ethylene-based copolymer" means a
copolymer comprised of ethylene and one or more C.sub.3-C.sub.20
comonomers.
[0026] As used herein, the term "HA" means the heat of fusion in
units of joules/gram on a first melt of the first ethylene-based
copolymer.
[0027] As used herein, the term "HB" means the heat of fusion in
units of joules/gram on the first melt of the second ethylene-based
copolymer.
[0028] As used herein, the term "intermolecular composition
distribution," (also "InterCD" or "intermolecular CD"), defines the
compositional heterogeneity in terms of ethylene content, among
polymer chains. It is expressed as the minimum deviation, analogous
to a standard deviation, in terms of weight percent ethylene from
the average ethylene composition for a given copolymer sample
needed to include a given weight percent of the total copolymer
sample, which is obtained by excluding equal weight fractions from
both ends of the distribution. The deviation need not be
symmetrical. When expressed as a single number, for example, an
intermolecular composition distribution of 15 wt % shall mean the
larger of the positive or negative deviations. For example, at 50
wt % intermolecular composition distribution the measurement is
akin to conventional composition distribution breadth index.
[0029] As used herein, the term "intramolecular composition
distribution" (also "IntraCD" or "intramolecular CD") defines the
compositional variation, in terms of ethylene, within a copolymer
chain. It is expressed as the ratio of the alpha-olefin to ethylene
along the segments of the same chain.
[0030] As used herein, the term "MIA" means the melt index, in
units of g/10 min or dg/min, of the first ethylene-based
copolymer.
[0031] As used herein, the term "MIB" means the melt index, in
units of g/10 min or dg/min, of the second ethylene-based
copolymer.
[0032] As used herein, the term "MnA" means the number-average
molecular weight of the first ethylene-based copolymer, as measured
by GPC.
[0033] As used herein, the term "MnB" means the number-average
molecular weight of the second ethylene-based copolymer, as
measured by GPC.
[0034] As used herein, the term "MwA" means the weight-average
molecular weight of the first ethylene-based copolymer in units of
grams/mole in terms of polystyrene, as measured by GPC.
[0035] As used herein, the term "MwB" means the weight-average
molecular weight of the second ethylene-based copolymer in units of
grams/mole in terms of polystyrene, as measured by GPC.
[0036] As used herein, the term "MWD" means the molecular weight
distribution, or ratio of weight-average molecular weight (Mw) to
number-average molecular weight (Mn).
[0037] As used herein, the term "melting point" means the highest
peak among principal and secondary melting peaks as determined by
DSC during the second melt, as discussed in further detail
below.
[0038] As used herein, the term "polyene" means monomers or
polymers having two or more unsaturations, e.g., dienes, trienes,
and the like.
[0039] As used herein, the term "polypropylene" means a polymer
made of at least 50% propylene units, preferably at least 70%
propylene units, more preferably at least 80% propylene units, even
more preferably at least 90% propylene units, even more preferably
at least 95% propylene units or 100% propylene units.
[0040] As used herein, the term "substantially linear structure"
means a polymer characterized as having less than 1 branch point
pendant with a carbon chain larger than 19 carbon atoms per 200
carbon atoms along a backbone.
[0041] For purposes of this specification and the claims appended
thereto, when a polymer or copolymer is referred to as comprising
an olefin, including, but not limited to ethylene, propylene, and
butene, the olefin present in such polymer or copolymer is the
polymerized form of the olefin. For example, when a copolymer is
said to have an "ethylene" content of 35-55 wt %, it is understood
that the mer unit in the copolymer is derived from ethylene in the
polymerization reaction and said derived units are present at 35-55
wt %, based upon the weight of the copolymer.
Polymeric Compositions
[0042] In some embodiments of the invention, the rheology modifiers
for lubrication fluids described herein comprise compositionally
disperse polymer blends and/or crystallinity disperse polymer
blends. These polymer blends comprise a first ethylene-based
copolymer and a second ethylene-based copolymer. Unless otherwise
specified, all references to first ethylene-based copolymer and
second ethylene-based copolymer refer to both compositionally
disperse polymer blends and crystallinity disperse polymer
blends.
[0043] The first ethylene-based copolymer, having a relatively
lower ethylene content, is a copolymer of ethylene, an alpha-olefin
comonomer, and optionally an internal olefin and optionally a
polyene, such as a diene.
[0044] The second ethylene-based copolymer, having a relatively
higher ethylene content, is a copolymer of ethylene, an
alpha-olefin and optionally an internal olefin and optionally a
polyene such as a diene.
[0045] The polymer blends of the invention comprise from about 35
to about 65 wt % of a first ethylene-based copolymer, with the
balance of the blend comprising the second ethylene-based
copolymer. In some embodiments, the blend comprises from about 38
to about 62 wt % of the first ethylene-based copolymer and from
about 38 to about 62 wt % of the second ethylene-based copolymer.
In further embodiments, the blend comprises from about 40 to about
60 wt % of the first ethylene-based copolymer and from about 40 to
about 60 wt % of the second ethylene-based copolymer.
[0046] For compositionally disperse polymer blends, the first
ethylene-based copolymer is characterized by an ethylene weight
percent (EA).
[0047] For crystallinity disperse polymer blends, the first
ethylene-based copolymer is characterized by a heat of fusion
(HA).
[0048] The first ethylene-based copolymer may be further
characterized by a melt index (MIA), a number-average molecular
weight (MnA), and a weight-average molecular weight (MwA).
[0049] In some embodiments, the EA of the first ethylene-based
copolymer (in wt %) is in the range of about
44.ltoreq.EA.ltoreq.52, or about 45.ltoreq.EA.ltoreq.51, or about
46.ltoreq.EA.ltoreq.50.
[0050] In the same or other embodiments, the HA of the first
ethylene-based copolymer (in J/g) is in the range of about
0.ltoreq.HA.ltoreq.15, or about 0.ltoreq.HA.ltoreq.10, or about
0.ltoreq.HA.ltoreq.5.
[0051] For compositionally disperse polymer blends, the second
ethylene-based copolymer is characterized by an ethylene weight
percent (EB).
[0052] For crystallinity disperse polymer blends, the second
ethylene-based copolymer is characterized by a heat of fusion
(HB).
[0053] The second ethylene-based copolymer may be further
characterized by a melt index (MIB), a number-average molecular
weight (MnB), and a weight-average molecular weight (MwB).
[0054] In some embodiments, the EB of the second ethylene-based
copolymer (in wt %) is in the range of about
68.ltoreq.EB.ltoreq.75, or about 69.ltoreq.EB.ltoreq.74, or about
70.ltoreq.EB.ltoreq.73.
[0055] In the same or other embodiments, the HB of the second
ethylene-based copolymer (in J/g) is in the range of about
40.ltoreq.HB.ltoreq.65, or about 42.ltoreq.HB.ltoreq.62, or about
45.ltoreq.HB.ltoreq.60.
[0056] In some embodiments of the compositionally disperse polymer
blend, the ethylene weight percent EA of the first ethylene-based
copolymer may be less than the ethylene weight percent EB of the
second ethylene-based copolymer.
[0057] In some embodiments, the compositionally disperse polymer
blends may be characterized by the difference in the ethylene
weight percent between the second and first ethylene-based
copolymers, EB and EA. In some embodiments, EB-EA.gtoreq.17, or
EB-EA.gtoreq.19, or EB-EA.gtoreq.21, or EB-EA.gtoreq.23. In some
embodiments, the difference in ethylene weight percent, EB and EA,
is in the range of about 17.ltoreq.EB-EA.ltoreq.25.
[0058] In some embodiments of the crystallinity disperse polymer
blends, the first melt heat of fusion HA of the first
ethylene-based copolymer may be less than the first melt heat of
fusion HB of the second ethylene-based copolymer.
[0059] In some embodiments, the crystallinity disperse polymer
blends may be characterized by the difference between the heats of
fusion of the second ethylene-based copolymer and the first
ethylene-based copolymer, HB and HA. In some embodiments,
HB-HA.gtoreq.15; in other embodiments, HB-HA.gtoreq.25; in still
other embodiments, HB-HA.gtoreq.35; in still yet other embodiments,
HB-HA.gtoreq.45. In some embodiments, the difference in the heat of
fusion, HB and HA, is in the range of
35.ltoreq.HB-HA.ltoreq.60.
[0060] The compositionally disperse and/or crystallinity disperse
polymer blends may be further characterized by the ratio of the
melt index of the first ethylene-based copolymer to the melt index
of the second ethylene-based copolymer, MIA/MIB. In some
embodiments, MIA/MIB is less than or equal to 3, less than or equal
to 2, less than or equal to 1.
[0061] The compositionally disperse and/or crystallinity disperse
polymer blends may be further characterized by the absolute value
of the difference in the melt index of the first ethylene-based
copolymer MIA and the melt index of the second ethylene-based
copolymer MIB. In some embodiments, |MIA-MIB|.ltoreq.3.0, or
|MIA-MIB|.ltoreq.2.5, or |MIA-MIB|.ltoreq.2.0, or
|MIA-MIB|.ltoreq.1.5, or |MIA-MIB|.ltoreq.1.1, or
|MIA-MIB|.ltoreq.1.0.
[0062] The first and second ethylene-based copolymers may be
characterized by a weight-average molecular weight (MwA and MwB,
respectively) of less than or equal to 130,000, or less than
120,000, or less than 110,000, or less than 100,000, or less than
90,000, or less than 80,000, or less than 70,000. Preferably, MwA
and MwB are from 70,000 to 95,000.
[0063] The first and second ethylene-based copolymers may be
characterized by a molecular weight distribution (MWD). Each of the
first and second ethylene-based copolymers has an MWD of less than
3.0, or less than 2.4, or less than 2.2, or less than 2.0.
Preferably, the MWD of each copolymer is from about 1.80 to about
1.95.
[0064] The MFR of the compositionally disperse and/or crystallinity
disperse polymer blends will be intermediate to the MFR of the
lower and higher ethylene content copolymers when these copolymers
have different MFRs. In some embodiments of the present invention,
the first and second ethylene-based copolymers each have an MFR of
from about 0.2 to about 25.
[0065] The first and second ethylene-based copolymers each comprise
ethylene and one or more comonomers. The comonomers are selected
from the group consisting of C.sub.3 to C.sub.20 alpha-olefins and
mixtures thereof. Preferably, the comonomer in each copolymer is
propylene, butene, hexene, octene or mixtures thereof.
[0066] In some embodiments, the first and second ethylene-based
copolymers may each further comprise a polyene monomer. In such
embodiments, each copolymer may further comprise up to 5 mole %, up
to 4 mole %, up to 3 mole %, up to 2 mole %, or up to 1 mole %
polyene-derived units.
[0067] In some embodiments, the first and second ethylene-based
copolymers may each comprise one or more polymer fractions having a
different Mn, a different Mw, or a different MWD.
[0068] In some embodiments, the first and/or second ethylene-based
copolymers may have different comonomer insertion sequences.
[0069] In some embodiments, the first and/or second ethylene-based
copolymers of a compositionally disperse polymer blend have a
substantially linear structure.
[0070] The substantially linear structure of the first and/or
second ethylene-based copolymer has less than 1 branch point
pendant with a carbon chain larger than 19 carbon atoms per 200
carbon atoms along a backbone, less than 1 branch point pendant
with a carbon chain larger than 19 carbon atoms per 300 branch
points, less than 1 branch point pendant with a carbon chain larger
than 19 carbon atoms per 500 carbon atoms, or less than 1 branch
point pendant with a carbon chain larger than 19 carbon atoms per
1000 carbon atoms, notwithstanding the presence of branch points
due to incorporation of the comonomer.
[0071] The discrete ethylene-based copolymers can be combined such
that the first ethylene-based copolymer, which is the less
crystalline ethylene-based copolymer (and typically the
ethylene-based copolymer with the lower wt % ethylene) can be
present in an amount of from about 35 to about 65 wt %, based on
the combined weight of the first and second ethylene-based
copolymers. In one or more embodiments, the first ethylene-based
copolymer can be present in an amount from about 38 to about 62 wt
%, or about 40 to about 60 wt %, based on the total weight of the
first and second copolymers.
[0072] The polymer blend can have an overall concentration or
content of ethylene-derived units ranging from about 55 mol % to
about 75 mol %. For example, the polymer blend can have a
concentration of ethylene-derived units ranging from a low of about
58 mol %, about 72 mol %, or about 60 mol % to a high of about 65
mol %, about 68 mol %, about 70 mol %, or about 72 mol %. The MFR
of the polymer blend can be intermediate to the MFR of the lowest
and highest ethylene content copolymers when the copolymers have
different MFRs.
Comonomer Components
[0073] Suitable comonomers include, but are not limited to,
propylene (C.sub.3) and other alpha-olefins, such as C.sub.4 to
C.sub.20 alpha-olefins (also referred to herein as
".alpha.-olefins"), and preferably propylene and C.sub.4 to
C.sub.12 .alpha.-olefins. The .alpha.-olefin comonomer can be
linear or branched, and two or more comonomers can be used, if
desired. Thus, reference herein to "an alpha-olefin comonomer"
includes one, two, or more alpha-olefin comonomers.
[0074] Examples of suitable comonomers include propylene, linear
C.sub.4 to C.sub.12 .alpha.-olefins, and .alpha.-olefins having one
or more C.sub.1 to C.sub.3 alkyl branches. Specific examples
include: propylene; 1-butene; 3-methyl-1-butene;
3,3-dimethyl-1-butene; 1-pentene; 1-pentene with one or more
methyl, ethyl or propyl substituents; 1-hexene with one or more
methyl, ethyl or propyl substituents; 1-heptene with one or more
methyl, ethyl or propyl substituents; 1-octene with one or more
methyl, ethyl or propyl substituents; 1-nonene with one or more
methyl, ethyl or propyl substituents; ethyl, methyl or
dimethyl-substituted 1-decene, or 1-dodecene. Preferred comonomers
include: propylene, 1-butene, 1-pentene, 3-methyl-1-butene,
1-hexene, 3-methyl-1-pentene, 4-methyl-1-pentene,
3,3-dimethyl-1-butene, 1-heptene, 1-hexene with a methyl
substituents on any of C.sub.3 to C.sub.5, 1-pentene with two
methyl substituents in any stoichiometrically acceptable
combination on C.sub.3 or C.sub.4, 3-ethyl-1-pentene, 1-octene,
1-pentene with a methyl substituents on any of C.sub.3 or C.sub.4,
1-hexene with two methyl substituents in any stoichiometrically
acceptable combination on C.sub.3 to C.sub.5, 1-pentene with three
methyl substituents in any stoichiometrically acceptable
combination on C.sub.3 or C.sub.4, 1-hexene with an ethyl
substituents on C.sub.3 or C.sub.4, 1-pentene with an ethyl
substituents on C.sub.3 and a methyl substituents in a
stoichiometrically acceptable position on C.sub.3 or C.sub.4,
1-decene, 1-nonene, 1-nonene with a methyl substituents on any of
C.sub.3 to C.sub.9, 1-octene with two methyl substituents in any
stoichiometrically acceptable combination on C.sub.3 to C.sub.7,
1-heptene with three methyl substituents in any stoichiometrically
acceptable combination on C.sub.3 to C.sub.6, 1-octene with an
ethyl substituents on any of C.sub.3 to C.sub.7, 1-hexene with two
ethyl substituents in any stoichiometrically acceptable combination
on C.sub.3 or C.sub.4, and 1-dodecene.
[0075] Other suitable comonomers can include internal olefins.
Preferred internal olefins are cis 2-butene and trans 2-butene.
Other internal olefins are contemplated. When an internal olefin is
present, negligible amounts, such as about 2 wt % or less of the
total amount of the internal olefin, can be present in the low
ethylene-content copolymer, and most of the internal olefin, such
as about 90 wt % or more of the total amount of the internal
olefin, can be present in the high ethylene-content copolymer.
[0076] Suitable comonomers can also include one or more polyenes.
Suitable polyenes can include non-conjugated dienes, preferably
those that are straight chain, hydrocarbon di-olefins or
cycloalkenyl-substituted alkenes, having about 6 to about 15 carbon
atoms, for example: (a) straight chain acyclic dienes, such as
1,4-hexadiene and 1,6-octadiene; (b) branched chain acyclic dienes,
such as 5-methyl-1,4-hexadiene; 3,7-dimethyl-1,6; (c) single ring
alicyclic dienes, such as 1,4-cyclohexadiene; 1,5-cyclo-octadiene
and 1,7-cyclododecadiene; (d) multi-ring alicyclic fused and
bridged ring dienes, such as tetrahydroindene, norbornadiene,
methyl-tetrahydroindene, dicyclopentadiene (DCPD),
bicyclo-(2.2.1)-hepta-2,5-diene, alkenyl, alkylidene, cycloalkenyl
and cycloalkylidene norbornenes, such as 5-methylene-2-norbornene
(MNB), 5-propenyl-2-norbornene, 5-isopropylidene-2-norbornene,
5-(4-cyclopentenyl)-2-norbornene, 5-cyclohexylidene-2-norbornene,
and 5-vinyl-2-norbornene (VNB); and (e) cycloalkenyl-substituted
alkenes, such as vinyl cyclohexene, allyl cyclohexene, vinyl
cyclooctene, 4-vinyl cyclohexene, allyl cyclodecene; and vinyl
cyclododecene. Of the non-conjugated dienes typically used, the
preferred dienes are dicyclopentadiene (DCPD), 1,4-hexadiene,
1,6-octadiene; 5-methyl-1,4-hexadiene; 3,7-dimethyl-1,6-octadiene;
5-methylene-2-norbornene, 5-ethylidene-2-norbornene (ENB), and
tetracyclo (.DELTA.-11,12) 5,8 dodecene. It is preferred to use
dienes that do not lead to the formation of long chain branches,
and non- or lowly branched polymer chains are preferred. Other
polyenes that can be used include cyclopentadiene and
octatetra-ene; and the like.
[0077] When a polyene is present, the ethylene-based copolymers can
include up to 5 mole %, up to 4 mole %, up to 3 mole %, up to 2
mole %, and up to 1 mole % polyene-derived units. In some
embodiments, the amount of polyene, when present, can range from
about 0.5 mole % to about 4 mole %; about 1.0 mole % to about 3.8
mole %; or about 1.5 mole % to about 2.5 mole %.
Catalyst
[0078] The terms "metallocene" and "metallocene catalyst
precursor," as used herein, refer to compounds possessing a
transition metal M, with cyclopentadienyl (Cp) ligands, at least
one non-cyclopentadienyl-derived ligand X, and zero or one
heteroatom-containing ligand Y, the ligands being coordinated to M
and corresponding in number to the valence thereof. The metallocene
catalyst precursors are generally neutral complexes but when
activated with a suitable co-catalyst yield an active metallocene
catalyst, which refers generally to an organometallic complex with
a vacant coordination site that can coordinate, insert, and
polymerize olefins. The metallocene catalyst precursor is
preferably one of, or a mixture of metallocene compounds, of either
or both of the following types:
[0079] (1) cyclopentadienyl (Cp) complexes that have two Cp ring
systems for ligands. The Cp ligands form a sandwich complex with
the metal and can be free to rotate (unbridged) or locked into a
rigid configuration through a bridging group. The Cp ring ligands
can be like or unlike unsubstituted, substituted, or a derivative
thereof such as a heterocyclic ring system, which may be
substituted, and the substitutions can be fused to form other
saturated or unsaturated rings systems such as tetrahydroindenyl,
indenyl, or fluorenyl ring systems. These cyclopentadienyl
complexes have the general formula:
(Cp.sup.1R.sup.1.sub.m)R.sup.3.sub.n(Cp.sup.2R.sup.2.sub.p)MX.sub.q
where Cp.sup.1 of ligand (Cp.sup.1R.sup.1.sub.m) and Cp.sup.2 of
ligand (Cp.sup.2R.sup.2.sub.p) are the same or different
cyclopentadienyl rings; R.sup.1 and R.sup.2 each is, independently,
a halogen or a hydrocarbyl, halocarbyl, hydrocarbyl-substituted
organometalloid or halocarbyl-substituted organometalloid group
containing up to about 20 carbon atoms; m is 0 to 5; p is 0 to 5;
and two R.sup.1 and/or R.sup.2 substituents on adjacent carbon
atoms of the cyclopentadienyl ring associated there with can be
joined together to form a ring containing from 4 to about 20 carbon
atoms; R.sup.3 is a bridging group; n is the number of atoms in the
direct chain between the two ligands and is 0 to 8, preferably 0 to
3; M is a transition metal having a valence of from 3 to 6,
preferably from group 4, 5, or 6 of the periodic table of the
elements and is preferably in its highest oxidation state; each X
is a non-cyclopentadienyl ligand and is, independently, a halogen
or a hydrocarbyl, oxyhydrocarbyl, halocarbyl,
hydrocarbyl-substituted organometalloid, oxyhydrocarbyl-substituted
organometalloid or halocarbyl-substituted organometalloid group
containing up to about 20 carbon atoms; q is equal to the valence
of M minus 2; and
[0080] (2) monocyclopentadienyl complexes that have only one Cp
ring system as a ligand. The Cp ligand forms a half-sandwich
complex with the metal and can be free to rotate (unbridged) or
locked into a rigid configuration through a bridging group to a
heteroatom-containing ligand. The Cp ring ligand can be
unsubstituted, substituted, or a derivative thereof such as a
heterocyclic ring system which may be substituted, and the
substitutions can be fused to form other saturated or unsaturated
rings systems such as tetrahydroindenyl, indenyl, or fluorenyl ring
systems. The heteroatom containing ligand is bound to both the
metal and optionally to the Cp ligand through the bridging group.
The heteroatom itself is an atom with a coordination number of
three from group VA or VIA of the periodic table of the elements.
These mono-cyclopentadienyl complexes have the general formula:
(Cp.sup.1R.sup.1.sub.m)R.sup.3.sub.n(Y.sub.rR.sup.2)MX.sub.s
wherein R.sup.1 is, each independently, a halogen or a hydrocarbyl,
halocarbyl, hydrocarbyl-substituted organometalloid or
halocarbyl-substituted organometalloid group containing up to about
20 carbon atoms; m is 0 to 5; and two R.sup.1 substituents on
adjacent carbon atoms of the cyclopentadienyl ring associated
therewith can be joined together to form a ring containing from 4
to about 20 carbon atoms; R.sup.3 is a bridging group; n is 0 to 3;
M is a transition metal having a valence of from 3 to 6, preferably
from group 4, 5, or 6 of the periodic table of the elements and is
preferably in its highest oxidation state; Y is a heteroatom
containing group in which the heteroatom is an element with a
coordination number of three from Group VA or a coordination number
of two from group VIA preferably nitrogen, phosphorous, oxygen, or
sulfur; R.sup.2 is a radical selected from a group consisting of
C.sub.1 to C.sub.20 hydrocarbon radicals, substituted C.sub.1 to
C.sub.20 hydrocarbon radicals, where one or more hydrogen atoms is
replaced with a halogen atom, and when Y is three coordinate and
unbridged there may be two R groups on Y each independently a
radical selected from a group consisting of C.sub.1 to C.sub.20
hydrocarbon radicals, substituted C.sub.1 to C.sub.20 hydrocarbon
radicals, where one or more hydrogen atoms is replaced with a
halogen atom, and each X is a non-cyclopentadienyl ligand and is,
independently, a halogen or a hydrocarbyl, oxyhydrocarbyl,
halocarbyl, hydrocarbyl-substituted organometalloid,
oxyhydrocarbyl-substituted organometalloid or
halocarbyl-substituted organometalloid group containing up to about
20 carbon atoms; s is equal to the valence of M minus 2.
[0081] Examples of suitable biscyclopentadienyl metallocenes of the
type described in group 1 above can be as discussed and described
in U.S. Pat. Nos. 5,324,800; 5,198,401; 5,278,119; 5,387,568;
5,120,867; 5,017,714; 4,871,705; 4,542,199; 4,752,597; 5,132,262;
5,391,629; 5,243,001; 5,278,264; 5,296,434; and 5,304,614, which
are incorporated by reference herein.
Noncoordinating Anions
[0082] The term "noncoordinating anion" (NCA) means an anion that
either does not coordinate to the transition metal cation or that
is only weakly coordinated to the cation thereby remaining
sufficiently labile to be displaced by a neutral Lewis base.
"Compatible" noncoordinating anions are those that are not degraded
to neutrality when the initially formed complex decomposes.
Further, the anion will not transfer an anionic substituents or
fragment to the cation so as to cause it to form a neutral four
coordinate metallocene compound and a neutral by-product from the
anion. Noncoordinating anions useful in accordance with this
invention are those that are compatible, stabilize the metallocene
cation in the sense of balancing its ionic charge in a +1 state,
and yet retain sufficient lability to permit displacement by an
ethylenically or acetylenically unsaturated monomer during
polymerization. Additionally, the anions useful in this invention
will be large or bulky in the sense of sufficient molecular size to
largely inhibit or prevent neutralization of the metallocene cation
by Lewis bases other than the polymerizable monomers that may be
present in the polymerization process. Typically the anion will
have a molecular size of greater than or equal to about 4
angstroms. NCAs are preferred because of their ability to produce a
target molecular weight polymer at a higher temperature than tends
to be the case with other activation systems such as alumoxane.
[0083] Descriptions of ionic catalysts for coordination
polymerization using metallocene cations activated by
non-coordinating anions appear in the early work in EP-A-0 277 003;
EP-A-0 277 004; WO92/00333; U.S. Pat. Nos. 5,198,401 and 5,278,119,
which are incorporated by reference herein. These references
disclose a preferred method of preparation where metallocenes
(bisCp and monoCp) are protonated by an anionic precursors such
that an alkyl/hydride group is abstracted from a transition metal
to make it both cationic and charge-balanced by the
non-coordinating anion. The use of ionizing ionic compounds not
containing an active proton but capable of producing both the
active metallocene cation and a noncoordinating anion are also
known. See, e.g., EP-A-0 426 637, EP-A-0 573 403 and U.S. Pat. No.
5,387,568, which are incorporated by reference herein. Reactive
cations other than Bronsted acids capable of ionizing the
metallocene compounds include ferrocenium triphenylcarbonium and
triethylsilylinium cations. Any metal or metalloid capable of
forming a coordination complex that is resistant to degradation by
water (or other Bronsted or Lewis Acids) may be used or contained
in the anion of the second activator compound. Suitable metals
include, but are not limited to, aluminum, gold, platinum and the
like. Suitable metalloids include, but are not limited to, boron,
phosphorus, silicon and the like.
[0084] An additional method for making the ionic catalysts uses
ionizing anionic pre-cursors which are initially neutral Lewis
acids but form the cation and anion upon ionizing reaction with the
metallocene compounds, for example, tris(pentafluorophenyl) boron
acts to abstract an alkyl, hydride or silyl ligand to yield a
metallocene cation and stabilizing non-coordinating anion. See,
e.g., EP-A-0 427 697 and EP-A-0 520 732, which are incorporated by
reference herein. Ionic catalysts for addition polymerization can
also be prepared by oxidation of the metal centers of transition
metal compounds by anionic precursors containing metallic oxidizing
groups along with the anion groups. See, e.g., EP-A-0 495 375,
which is incorporated by reference here.
Non-Ionic Activators
[0085] Where the metal ligands include halide moieties, for
example, (methyl-phenyl) silylene (tetra-methyl-cyclopentadienyl)
(tert-butyl-amido) zirconium dichloride, which are not capable of
ionizing abstraction under standard conditions, they can be
converted via known alkylation reactions with organometallic
compounds such as lithium or aluminum hydrides or alkyls,
alkylalumoxanes, Grignard reagents, etc. See, e.g., EP-A-0 500 944,
EP-A1-0 570 982 and EP-A1-0 612 768 for processes describing the
reaction of alkyl aluminum compounds with dihalide substituted
metallocene compounds prior to or with the addition of activating
anionic compounds. For example, an aluminum alkyl compound may be
mixed with the metallocene prior to its introduction into the
reaction vessel. Since the alkyl aluminum is also suitable as a
scavenger its use in excess of that normally stoichiometrically
required for alkylation of the metallocene will permit its addition
to the reaction solvent with the metallocene compound. Normally,
alumoxane would not be added with the metallocene so as to avoid
premature activation, but can be added directly to the reaction
vessel in the presence of the polymerizable monomers when serving
as both scavenger and alkylating activator. Alumoxanes may also
fulfill a scavenging function.
[0086] Known alkylalumoxanes are additionally suitable as catalyst
activators, particularly for those metallocenes comprising halide
ligands. The alumoxane component useful as catalyst activator
typically is an oligomeric aluminum compound represented by the
general formula (R--Al--O) n, which is a cyclic compound, or
R(R--Al--O)nAlR.sub.2, which is a linear compound. In the general
alumoxane formula R is a C.sub.1 to C.sub.5 alkyl radical, for
example, methyl, ethyl, propyl, butyl or pentyl, and "n" is an
integer from 1 to about 50. Most preferably, R is methyl and "n" is
at least 4, i.e., methylalumoxane (MAO). Alumoxanes can be prepared
by various procedures known in the art. For example, an aluminum
alkyl may be treated with water dissolved in an inert organic
solvent, or it may be contacted with a hydrated salt, such as
hydrated copper sulfate suspended in an inert organic solvent, to
yield an alumoxane. Generally, however prepared, the reaction of an
aluminum alkyl with a limited amount of water yields a mixture of
the linear and cyclic species of the alumoxane.
Polymerization Process
[0087] Each discrete ethylene-based copolymer can be polymerized in
a single, well stirred tank reactor in solution. The viscosity of
the solution during polymerization can be less than 10000 cPs, or
less than 7000 cPs, and preferably less than 500 cPs. The reactor
is preferably a liquid filled, continuous flow, stirred tank
reactor providing full back mixing for random copolymer production.
Solvent, monomers, and catalyst(s) are fed to the reactor. When two
or more reactors are utilized, solvent, monomers, and/or
catalyst(s) is fed to the first reactor or to one or more
additional reactors.
[0088] Reactors may be cooled by reactor jackets or cooling coils,
autorefrigeration, prechilled feeds or combinations of all three to
absorb the heat of the exothermic polymerization reaction.
Autorefrigerated reactor cooling requires the presence of a vapor
phase in the reactor. Adiabatic reactors with prechilled feeds are
preferred in which the polymerization exotherm is absorbed by
permitting a temperature rise of the polymerizing liquid.
[0089] Use of hydrogen to control molecular weight may be avoided
or reduced, if desired. The reactor temperature may be used to
control the molecular weight of the polymer fraction produced. In
series operation, this gives rise to a temperature difference
between reactors, which is helpful for controlling polymer
molecular weight.
[0090] Reactor temperature can be selected depending upon the
effect of temperature on catalyst deactivation rate and polymer
properties and/or extent of monomer depletion. When using more than
one reactor, generally temperatures should not exceed the point at
which the concentration of catalyst in the second reactor is
insufficient to make the desired polymer component in the desired
amount. Therefore, reaction temperature can be determined by the
details of the catalyst system.
[0091] In general, a single reactor or first reactor in a series
will operate at a reactor temperature from about 0.degree. C. to
about 200.degree. C., or from about 10.degree. C. to about
110.degree. C., or from about 20.degree. C. to about 90.degree. C.
Preferably, reaction temperatures are from about 20.degree. C. to
about 90.degree. C. or from about 20.degree. C. to about 70.degree.
C. When using on or more additional reactors, the additional
reactor temperature will vary from about 40.degree. C. to about
200.degree. C., with about 50.degree. C. to about 140.degree. C.
preferred, and about 60.degree. C. to about 120.degree. C. more
preferred. Ranges from any of the recited lower limits to any of
the recited upper limits are contemplated by the inventors and
within the scope of the present description. In copolymerization
techniques that utilize one or more bis-Cp catalysts with one or
more mono-Cp catalysts, a lower reaction temperature is preferred
for reactions utilizing mono-Cp catalyst when compared to the
bis-Cp catalyst.
[0092] Reaction pressure is determined by the details of the
catalyst system. In general a reactor, whether a single reactor or
each of a series of reactors, operates at a reactor pressure of
less than 2500 pounds per square inch (psi) (17.23 MPa), or less
than 2200 psi (15.16 MPa) or less than 2000 psi (13.78 MPa).
Preferably, reactor pressure is from about atmospheric pressure to
about 2000 psi (13.78 MPa), or from about 200 psi (1.38 MPa) to
about 2000 psi (13.78 MPa), or from about 300 psi (2.07 MPa) to
about 1800 psi (12.40 MPa). Ranges from any of the recited lower
limits to any of the recited upper limits are contemplated and
within the scope of the present description.
[0093] In the case of less stable catalysts, catalyst can also be
fed to a second reactor when the selected process uses reactors in
series. Optimal temperatures can be achieved, particularly for
series operation with progressively increasing polymerization
temperature, by using bis cyclopentadienyl catalyst systems
containing hafnium as the transition metal, especially those having
a covalent, single atom bridge coupling the two cyclopentadienyl
rings.
[0094] Particular reactor configurations and processes suitable for
use in the processes described herein are described in detail in
U.S. Pat. No. 6,319,998 and U.S. Provisional Patent Application
having Ser. No. 60/243,192, filed Oct. 25, 2000, which are
incorporated by reference herein.
[0095] Branching is introduced by the choice of polymerization
catalysts or process. The copolymerization process may occur with
or without hydrogen present. However, operation without hydrogen is
preferred because it inhibits branching in the copolymers since it
lead to chain ends which are completely or substantially saturated.
Without being limited by theory, it is believed that these
saturated polymers cannot participate in the principal branching
pathway where preformed polymers with unsaturated chain ends are
reincorporated into new growing chains, which lead to branched
polymers.
[0096] In alternative embodiments, the first and second
ethylene-based copolymers can be polymerized in an alkane solvent,
either hexane in a solution process or propylene in a slurry
process and finished to remove the solvent. The first and second
ethylene-based copolymers can have a medium viscosity and a
molecular weight in excess of that needed in the final lubricant
formulation. For example, most of the traditional EPDM
manufacturing plants cannot "finish" low viscosity polymers having
the right viscosity for lubricant formulations. In another example,
low viscosity copolymers tend to cold flow upon storage. The second
example can be particularly true for amorphous copolymers, which
have a lower plateau modulus. The bales are then processed by a
series of steps to create the final lubricant composition.
[0097] In some embodiments, ethylene and a first comonomer can be
polymerized in the presence of a first metallocene catalyst in a
first polymerization reaction zone under first polymerization
conditions to produce a first effluent comprising a first
ethylene-based copolymer. Ethylene and a second comonomer can also
be polymerized in the presence of a second metallocene catalyst in
a second polymerization reaction zone under second polymerization
conditions to produce a second effluent comprising a second
ethylene-based copolymer. The resulting discrete copolymers can
then be mixed or otherwise blended to provide the rheology
modifier.
[0098] In one or more embodiments, the first and second
polymerization conditions can be independently selected from the
group consisting of slurry phase, solution phase and bulk phase.
When the first and second polymerization conditions are solution
phase, forming the polymer blend can further include substantial
removal of the solvent from the first effluent, the second
effluent, or both to produce a solid polymer blend.
[0099] In one or more embodiments, separate polymerizations can be
performed in parallel with the effluent polymer solutions from
three reactors combined downstream before the finishing. In another
embodiment, separate polymerizations may be performed in series,
where the effluent of one reactor is fed to the next reactor. In
still another embodiment, the separate polymerization may be
performed in the same reactor, preferably in sequential
polymerizations.
[0100] The ethylene-based copolymers can be polymerized by a
metallocene catalyst to form the first ethylene-based copolymer in
one reactor and the second ethylene-based copolymer in another
reactor. The first and second ethylene-based copolymers can be
combined and then subjected to finishing steps to produce the
polymer blend. The first ethylene-based copolymer can be made
first; alternatively, the second ethylene-based copolymer can be
made first in a series reactor configuration or the ethylene-based
copolymers can be made simultaneously in a parallel reactor
configuration.
[0101] The metallocene catalysts, and their use with
non-coordinating ions and non-ionic activators used in the
polymerization process can be as discussed and described in U.S.
Provisional Patent Application having Ser. No. 61/173,528, entitled
"Ethylene-Based Copolymers and Lubricating Oil Compositions
Containing the Same," bearing attorney docket number 2009EM079-PRV,
filed on Apr. 28, 2009, which is incorporated by reference
herein.
[0102] Examples of suitable bis-cyclopentadienyl metallocenes,
include, but are not limited to the type disclosed in U.S. Pat.
Nos. 5,324,800; 5,198,401; 5,278,119; 5,387,568; 5,120,867;
5,017,714; 4,871,705; 4,542,199; 4,752,597; 5,132,262; 5,391,629;
5,243,001; 5,278,264; 5,296,434; and 5,304,614, which are
incorporated by reference herein.
Lubrication Oil Composition
[0103] Lubricating oil compositions containing the polymer blend
and one or more base oils (or basestocks) are also provided. The
basestock can be or include natural or synthetic oils of
lubricating viscosity, whether derived from hydrocracking,
hydrogenation, other refining processes, unrefined processes, or
re-refined processes. The basestock can be or include used oil.
Natural oils include animal oils, vegetable oils, mineral oils and
mixtures thereof. Synthetic oils include hydrocarbon oils,
silicon-based oils, and liquid esters of phosphorus-containing
acids. Synthetic oils may be produced by Fischer-Tropsch
gas-to-liquid synthetic procedure as well as other gas-to-liquid
oils.
[0104] In one embodiment, the basestock is or includes a
polyalphaolefin (PAO) including a PAO-2, PAO-4, PAO-5, PAO-6, PAO-7
or PAO-8 (the numerical value relating to Kinematic Viscosity at
100.degree. C.). Preferably, the polyalphaolefin is prepared from
dodecene and/or decene. Generally, the polyalphaolefin suitable as
an oil of lubricating viscosity has a viscosity less than that of a
PAO-20 or PAO-30 oil. In one or more embodiments, the basestock can
be defined as specified in the American Petroleum Institute (API)
Base Oil Interchangeability Guidelines. For example, the basestock
can be or include an API Group I, II, III, IV, V oil or mixtures
thereof.
[0105] In one or more embodiments, the basestock can include oil or
blends thereof conventionally employed as crankcase lubricating
oils. For example, suitable basestocks can include crankcase
lubricating oils for spark-ignited and compression-ignited internal
combustion engines, such as automobile and truck engines, marine
and railroad diesel engines, and the like. Suitable basestocks can
also include those oils conventionally employed in and/or adapted
for use as power transmitting fluids such as automatic transmission
fluids, tractor fluids, universal tractor fluids and hydraulic
fluids, heavy duty hydraulic fluids, power steering fluids and the
like. Suitable basestocks can also be or include gear lubricants,
industrial oils, pump oils and other lubricating oils.
[0106] In one or more embodiments, the basestock can include not
only hydrocarbon oils derived from petroleum, but also include
synthetic lubricating oils such as esters of dibasic acids; complex
esters made by esterification of monobasic acids, polyglycols,
dibasic acids and alcohols; polyolefin oils, etc. Thus, the
lubricating oil compositions described can be suitably incorporated
into synthetic base oil basestocks such as alkyl esters of
dicarboxylic acids, polyglycols and alcohols; polyalpha-olefins;
polybutenes; alkyl benzenes; organic esters of phosphoric acids;
polysilicone oils; etc. The lubricating oil composition can also be
utilized in a concentrate form, such as from 1 wt % to 49 wt % in
oil, e.g., mineral lubricating oil, for ease of handling, and may
be prepared in this form by carrying out the reaction of the
invention in oil as previously described.
[0107] The lubrication oil composition can include a basestock and
one or more compositionally disperse polymer blends and/or one or
more crystallinity disperse polymer blends, and optionally, a pour
point depressant. The lubrication oil composition can have a
thickening efficiency greater than 1.5, or greater than 1.7, or
greater than 1.9, or greater than 2.2, or greater than 2.4 or
greater than 2.6. The lubrication oil composition can have a shear
stability index less than 55, or less than 45, or less than 35, or
less than 30, or less than 25, or less than 20, or less than 15.
The lubrication oil composition can have a complex viscosity at
-35.degree. C. of less than 500, or less than 450, or less than
300, or less than 100, or less than 50, or less 20, or less than 10
centistokes (cSt). The lubrication oil composition can have a Mini
Rotary Viscometer (MRV) viscosity at -35.degree. C. in a 10W-50
formulation of less than 60,000 cps according to ASTM 1678. The
lubrication oil composition can have any combination of desired
properties. For example, the lubrication oil composition can have a
thickening efficiencies greater than about 1.5 or greater than
about 2.6, a shear stability index of less than 55 or less than 35
or less than 25, a complex viscosity at -35.degree. C. of less than
500 cSt or less than 300 cSt or less than 50 cSt, and/or a Mini
Rotary Viscometer (MRV) viscosity at -35.degree. C. in a 10W-50
formulation of less than about 60,000 cps according to ASTM
1678.
[0108] The lubrication oil composition preferably comprises about
2.5 wt %, or about 1.5 wt %, or about 1.0 wt % or about 0.5 wt % of
the compositionally disperse and/or crystallinity disperse polymer
blend. In some embodiments, the amount of the polymer blend in the
lubrication oil composition can range from a low of about 0.5 wt %,
about 1 wt %, or about 2 wt % to a high of about 2.5 wt %, about 3
wt %, about 5 wt %, or about 10 wt %.
Oil Additives
[0109] The lubricating oil compositions of the invention can
optionally contain one or more conventional additives, such as, for
example, pour point depressants, antiwear agents, antioxidants,
other viscosity-index improvers, dispersants, corrosion inhibitors,
anti-foaming agents, detergents, rust inhibitors, friction
modifiers, and the like.
[0110] Corrosion inhibitors, also known as anti-corrosive agents,
reduce the degradation of the metallic parts contacted by the
lubricating oil composition. Illustrative corrosion inhibitors
include phosphosulfurized hydrocarbons and the products obtained by
reaction of a phosphosulfurized hydrocarbon with an alkaline earth
metal oxide or hydroxide, preferably in the presence of an
alkylated phenol or of an alkylphenol thioester, and also
preferably in the presence of carbon dioxide. Phosphosulfurized
hydrocarbons are prepared by reacting a suitable hydrocarbon such
as a terpene, a heavy petroleum fraction of a C.sub.2 to C.sub.6
olefin polymer such as polyisobutylene, with from 5 to 30 wt % of a
sulfide of phosphorus for 1/2 to 15 hours, at a temperature in the
range of 66.degree. C. to 316.degree. C. Neutralization of the
phosphosulfurized hydrocarbon may be effected in the manner known
by those skilled in the art.
[0111] Oxidation inhibitors, or antioxidants, reduce the tendency
of mineral oils to deteriorate in service, as evidenced by the
products of oxidation such as sludge and varnish-like deposits on
the metal surfaces, and by viscosity growth. Such oxidation
inhibitors include alkaline earth metal salts of
alkylphenolthioesters having C.sub.5 to C.sub.12 alkyl side chains,
e.g., calcium nonylphenate sulfide, barium octylphenate sulfide,
dioctylphenylamine, phenylalphanaphthylamine, phosphosulfurized or
sulfurized hydrocarbons, etc. Other oxidation inhibitors or
antioxidants useful in this invention include oil-soluble copper
compounds, such as described in U.S. Pat. No. 5,068,047.
[0112] Friction modifiers serve to impart the proper friction
characteristics to lubricating oil compositions such as automatic
transmission fluids. Representative examples of suitable friction
modifiers are found in U.S. Pat. No. 3,933,659, which discloses
fatty acid esters and amides; U.S. Pat. No. 4,176,074 which
describes molybdenum complexes of polyisobutenyl succinic
anhydride-amino alkanols; U.S. Pat. No. 4,105,571 which discloses
glycerol esters of dimerized fatty acids; U.S. Pat. No. 3,779,928
which discloses alkane phosphonic acid salts; U.S. Pat. No.
3,778,375 which discloses reaction products of a phosphonate with
an oleamide; U.S. Pat. No. 3,852,205 which discloses
S-carboxyalkylene hydrocarbyl succinimide, S-carboxyalkylene
hydrocarbyl succinamic acid and mixtures thereof; U.S. Pat. No.
3,879,306 which discloses N(hydroxyalkyl)alkenyl-succinamic acids
or succinimides; U.S. Pat. No. 3,932,290 which discloses reaction
products of di-(lower alkyl) phosphites and epoxides; and U.S. Pat.
No. 4,028,258 which discloses the alkylene oxide adduct of
phosphosulfurized N-(hydroxyalkyl) alkenyl succinimides. Preferred
friction modifiers are succinate esters, or metal salts thereof, of
hydrocarbyl substituted succinic acids or anhydrides and
thiobis-alkanols such as described in U.S. Pat. No. 4,344,853.
[0113] Dispersants maintain oil insolubles, resulting from
oxidation during use, in suspension in the fluid, thus preventing
sludge flocculation and precipitation or deposition on metal parts.
Suitable dispersants include high molecular weight N-substituted
alkenyl succinimides, the reaction product of oil-soluble
polyisobutylene succinic anhydride with ethylene amines such as
tetraethylene pentamine and borated salts thereof. High molecular
weight esters (resulting from the esterification of olefin
substituted succinic acids with mono or polyhydric aliphatic
alcohols) or Mannich bases from high molecular weight alkylated
phenols (resulting from the condensation of a high molecular weight
alkylsubstituted phenol, an alkylene polyamine and an aldehyde such
as formaldehyde) are also useful as dispersants.
[0114] Pour point depressants ("ppd"), otherwise known as lube oil
flow improvers, lower the temperature at which the fluid will flow
or can be poured. Any suitable pour point depressant known in the
art can be used. For example, suitable pour point depressants
include, but are not limited to, one or more C.sub.8 to C.sub.18
dialkylfumarate vinyl acetate copolymers, polymethyl methacrylates,
alkylmethacrylates and wax naphthalene.
[0115] Foam control can be provided by any one or more
anti-foamants. Suitable anti-foamants include polysiloxanes, such
as silicone oils and polydimethyl siloxane.
[0116] Anti-wear agents reduce wear of metal parts. Representatives
of conventional antiwear agents are zinc dialkyldithiophosphate and
zinc diaryldithiosphate, which also serves as an antioxidant.
[0117] Detergents and metal rust inhibitors include the metal salts
of sulphonic acids, alkyl phenols, sulfurized alkyl phenols, alkyl
salicylates, naphthenates and other oil soluble mono- and
dicarboxylic acids. Highly basic (viz, overbased) metal sales, such
as highly basic alkaline earth metal sulfonates (especially Ca and
Mg salts) are frequently used as detergents.
[0118] Compositions containing these conventional additives can be
blended with the basestock in amounts effective to provide their
normal attendant function. Thus, typical formulations can include,
in amounts by weight, a VI improver (from about 0.01% to about
12%); a corrosion inhibitor (from about 0.01% to about 5%); an
oxidation inhibitor (from about 0.01% to about 5%); depressant (of
from about 0.01% to about 5%); an anti-foaming agent (from about
0.001% to about 3%); an anti-wear agent (from about 0.001% to about
5%); a friction modifier (from about 0.01% to about 5%); a
detergent/rust inhibitor (from about 0.01 to about 10%); and a base
oil.
[0119] When other additives are used, it may be desirable, although
not necessary, to prepare additive concentrates that include
concentrated solutions or dispersions of the VI improver (in
concentrated amounts), together with one or more of the other
additives, such a concentrate denoted an "additive package,"
whereby several additives can be added simultaneously to the
basestock to form a lubrication oil composition. Dissolution of the
additive concentrate into the lubrication oil can be facilitated by
solvents and by mixing accompanied with mild heating, but this is
not essential. The additive-package can be formulated to contain
the VI improver and optional additional additives in proper amounts
to provide the desired concentration in the final formulation when
the additive-package is combined with a predetermined amount of
base oil.
Blending With Basestock Oils
[0120] Conventional blending methods are described in U.S. Pat. No.
4,464,493, which is incorporated by reference herein. This
conventional process requires passing the polymer through an
extruder at elevated temperature for degradation of the polymer and
circulating hot oil across the die face of the extruder while
reducing the degraded polymer to particle size upon issuance from
the extruder and into the hot oil. The pelletized, solid polymer
compositions of the present invention, as described above, can be
added by blending directly with the base oil so as give directly
viscosity for the VI improver, so that the complex multi-step
process of the prior art is not needed. The solid polymer
composition can be dissolved in the basestock without the need for
additional shearing and degradation processes.
[0121] The polymer compositions will be soluble at room temperature
in lube oils at up to 10 percent concentration in order to prepare
a viscosity modifier concentrate. Such concentrates, including
eventually an additional additive package including the typical
additives used in lube oil applications as described above, are
generally further diluted to the final concentration (usually
around 1%) by multi-grade lube oil producers. In this case, the
concentrate will be a pourable homogeneous solid free solution.
[0122] The polymer blend compositions preferably have an SSI
(determined according to ASTM D97) of from about 10 to about
50.
Specific Embodiments
[0123] In one or more specific embodiments, the present invention
is directed to a polymer blend composition for use as a VI improver
comprising a first ethylene-based copolymer and a second
ethylene-based copolymer. The first copolymer has an ethylene
content from about 44 to about 52 wt %, or from about 45 to about
51 wt %, or from about 46 to about 50 wt %; the second copolymer
has an ethylene content from about 68 to about 75 wt %, or from
about 69 to about 74 wt %, or from about 70 to about 73 wt %.
Additionally, the ethylene content of the second copolymer is at
least about 17 wt %, or at least about 19 wt %, or at least about
21 wt % greater than that ethylene content of the first
copolymer.
[0124] In the same or other embodiments, the first copolymer has a
first melt heat of fusion from about 0 to about 15 J/g, or from
about 0 to about 10 J/g, or from about 0 to about 5 J/g; the second
copolymer has a first melt heat of fusion from about 40 to about 65
J/g, or from about 42 to about 62 J/g, or from about 45 to about 60
J/g. Additionally, the heat of fusion of the second copolymer is at
least about 25 J/g, or at least about 35 J/g, or at least about 45
J/g greater than that ethylene content of the first copolymer.
[0125] Further, the first and second copolymers have a
weight-average molecular weight (Mw) less than or equal to about
130,000. In the same or other embodiments, the ratio of the melt
index of the first copolymer to the melt index of the second
copolymer is less than or equal to about 3.0. Additionally, the
composition comprises from about 35 to about 65 wt %, or from about
38 to about 62 wt %, or from about 40 to about 60 wt % of the first
copolymer, based on the total weight of the first and second
copolymers.
[0126] The first and second copolymers of the invention may each
comprise one or more comonomers selected from the group consisting
of C.sub.3-C.sub.20 alpha-olefins.
[0127] Further embodiments of the present invention include
lubricating oil compositions comprising a lubricating oil basestock
and any of the polymer blend compositions of the invention
described herein.
Polymer Analyses
[0128] The ethylene contents as an ethylene weight percent (C.sub.2
wt %) for the ethylene-based copolymers were determined according
to ASTM D1903.
[0129] DSC Measurements of the crystallization temperature,
T.sub.c, and melting temperature, T.sub.m, of the ethylene-based
copolymers were measured using a TA Instruments Model 2910 DSC.
Typically, 6-10 mg of a polymer was sealed in a pan with a hermetic
lid and loaded into the instrument. In a nitrogen environment, the
sample was first cooled to -100.degree. C. at 20.degree. C./min. It
was then heated to 220.degree. C. at 10.degree. C./min and melting
data (first heat) were acquired. This provides information on the
melting behavior under as-received conditions, which can be
influenced by thermal history as well as sample preparation method.
The sample was then equilibrated at 220.degree. C. to erase its
thermal history. Crystallization data (first cool) were acquired by
cooling the sample from the melt to -100.degree. C. at 10.degree.
C./min and equilibrated at -100.degree. C. Finally the sample was
heated again to 220.degree. C. at 10.degree. C./min to acquire
additional melting data (second heat). The endothermic melting
transition (first and second heat) and exothermic crystallization
transition (first cool) were analyzed for peak temperature and area
under the peak. The term "melting point," as used herein, is the
highest peak among principal and secondary melting peaks as
determined by DSC during the second melt, discussed above. The
thermal output was recorded as the area under the melting peak of
the sample, which was typically at a maximum peak at about
30.degree. C. to about 175.degree. C. and occurred between the
temperatures of about 0.degree. C. and about 200.degree. C. The
thermal output was measured in Joules as a measure of the heat of
fusion. The melting point is recorded as the temperature of the
greatest heat absorption within the range of melting of the
sample.
Gelation Visual Test
[0130] A 10 ml sample of the solution was placed into a 40 ml glass
vial with screw cap. A typical vial is available from VWR
Corporation as catalog number (VWR cat #: C236-0040). The sample
was heated in an 80.degree. C. oven for 1 hour to remove any
thermal history. The vial was stored at 10.degree. C. for 4 to 6
hours in a Low Temperature Incubator. A typical incubator is
available from VWR Corporation as catalog number 35960-057. The
vial was then stored at -15.degree. C.+/-0.5.degree. C. overnight
in a chest freezer. A typical chest freezer is Revco Model UTL
750-3-A30. A thermocouple was placed into a reference vial,
identical to the sample, but containing only the solvent or base
oil to monitor the actual sample temperature. After 16 hours the
vial was removed from the freezer, while maintaining the cap in
place and the vial was immediately tilted from about 80.degree. to
90.degree. to an almost horizontal position. If condensation formed
on the outside of the vial, the condensation was wiped off with a
paper towel. The following visual grading was used to rate the
sample visually.
TABLE-US-00001 GRADE DESCRIPTION DETAILED COMMENTS 0 No gel Free
flowing fluid with mirror surface 1 Light gel Slight
non-homogeneity, surface roughness 2 Medium gel Large
non-homogeneity, slight pulling away from vial 3 Heavy gel Pulls
away from vial, large visible lumps 4 Solid Solid gel
[0131] Molecular weight (weight-average molecular weight, Mw,
number-average molecular weight, Mn, and molecular weight
distribution, Mw/Mn or MWD) were determined using a High
Temperature Size Exclusion Chromatograph (either from Waters
Corporation or Polymer Laboratories), equipped with a differential
refractive index detector (DRI), an online light scattering (LS)
detector, and a viscometer. Experimental details not described
below, including how the detectors were calibrated, are described
in: T. Sun, P. Brant, R. R. Chance, and W. W. Graessley,
MACROMOLECULES, Volume 34, Number 19, 6812-6820, (2001).
[0132] Three Polymer Laboratories PLgel 10 mm Mixed-B columns were
used. The nominal flow rate was 0.5 cm.sup.3/min, and the nominal
injection volume was 300 .mu.L. The various transfer lines, columns
and differential refractometer (the DRI detector) were contained in
an oven maintained at 145.degree. C. Solvent for the SEC experiment
was prepared by dissolving 6 grams of butylated hydroxy toluene as
an antioxidant in 4 liters of Aldrich reagent grade 1, 2, 4
trichlorobenzene (TCB). The TCB mixture was then filtered through a
0.7 .mu.m glass pre-filter and subsequently through a 0.1 .mu.m
Teflon filter. The TCB was then degassed with an online degasser
before entering the SEC. Polymer solutions were prepared by placing
dry polymer in a glass container, adding the desired amount of TCB,
then heating the mixture at 160.degree. C. with continuous
agitation for about 2 hours. All quantities were measured
gravimetrically. The TCB densities used to express the polymer
concentration in mass/volume units are 1.463 g/ml at room
temperature and 1.324 g/ml at 145.degree. C. The injection
concentration ranged from about 1.0 mg/ml to about 2.0 mg/ml, with
lower concentrations being used for higher molecular weight
samples. Prior to running each sample the DRI detector and the
injector were purged. Flow rate in the apparatus was then increased
to 0.5 ml/minute, and the DRI was allowed to stabilize for about 8
to 9 hours before injecting the first sample. The LS laser was
turned on from about 1 hour to about 1.5 hours before running
samples.
[0133] The concentration, c, at each point in the chromatogram is
calculated from the baseline-subtracted DRI signal, I.sub.DRI,
using the following equation:
c=K.sub.DRII.sub.DRI/(dn/dc)
where K.sub.DRI is a constant determined by calibrating the DRI,
and (dn/dc) is the same as described below for the light scattering
(LS) analysis. Units on parameters throughout this description of
the SEC method are such that concentration is expressed in
g/cm.sup.3, molecular weight is expressed in g/mole, and intrinsic
viscosity is expressed in dL/g.
[0134] The light scattering detector used was a Wyatt Technology
High Temperature mini-DAWN. The polymer molecular weight, M, at
each point in the chromatogram is determined by analyzing the LS
output using the Zimm model for static light scattering (M. B.
Huglin, LIGHT SCATTERING FROM POLYMER SOLUTIONS, Academic Press,
1971):
K o c .DELTA. R ( .theta. ) = 1 MP ( .theta. ) + 2 A 2 c
##EQU00001##
Here, .DELTA.R(.theta.) is the measured excess Rayleigh scattering
intensity at scattering angle .theta., c is the polymer
concentration determined from the DRI analysis, A.sub.2 is the
second virial coefficient [for purposes of this invention and the
claims thereto, A.sub.2=0.0006 for propylene polymers and 0.001
otherwise], P(.theta.) is the form factor for a monodisperse random
coil (M. B. Huglin, LIGHT SCATTERING FROM POLYMER SOLUTIONS,
Academic Press, 1971), and K.sub.o is the optical constant for the
system:
K o = 4 .pi. 2 n 2 ( n / c ) 2 .lamda. 4 N A ##EQU00002##
in which N.sub.A is Avogadro's number, and (dn/dc) is the
refractive index increment for the system. The refractive index,
n=1.500 for TCB at 145.degree. C. and k=690 nm. For purposes of
this invention and the claims thereto (dn/dc)=0.104 for propylene
polymers and 0.1 otherwise.
[0135] A high temperature Viscotek Corporation viscometer, which
has four capillaries arranged in a Wheatstone bridge configuration
with two pressure transducers, was used to determine specific
viscosity. One transducer measures the total pressure drop across
the detector, and the other, positioned between the two sides of
the bridge, measures a differential pressure. The specific
viscosity, .eta..sub.s, for the solution flowing through the
viscometer is calculated from their outputs. The intrinsic
viscosity, [.eta.], at each point in the chromatogram is calculated
from the following equation:
.eta..sub.s=C[.eta.]+0.3(c[.eta.]).sup.2
where c is concentration and was determined from the DRI
output.
[0136] The branching index (g') is calculated using the output of
the SEC-DRI-LS-VIS method as follows. The average intrinsic
viscosity, [.eta.].sub.avg, of the sample is calculated by:
[ .eta. ] avg = c i [ .eta. ] i c i ##EQU00003##
where the summations are over the chromatographic slices, i,
between the integration limits.
[0137] The branching index g' is defined as:
g ' = [ .eta. ] avg kM v .alpha. ##EQU00004##
where, for purpose of this invention and claims thereto,
.alpha.=0.695 for ethylene, propylene, and butene polymers; and
k=0.000579 for ethylene polymers, k=0.000228 for propylene
polymers, and k=0.000181 for butene polymers. M.sub.v is the
viscosity-average molecular weight based on molecular weights
determined by LS analysis.
[0138] Anton-Parr Low Temperature Solution Rheology (low
temperature rheology) experiments were done on an Anton-Parr Model
MCR501 rheometer using a 1'' cone and plate setup. The cone has a
nominal 1 degree angle and 50 micron gap. About 100 microliters of
sample is deposited on the bottom plate using a syringe-pipette.
The cone is then lowered onto the plate so that the volume between
the cone and plate is fully occupied by solution. The temperature
is then lowered at a cooling rate of 1.5.degree. C./min. while
measuring the complex viscosity at an angular frequency of 0.1
radians/sec. applying a 10% strain and recording a value every
minute. The viscosity at 0.1 rad/sec is then plotted as a function
of temperature to observe the effect of gelation.
Scanning Brookfield Viscometer
[0139] The Scanning Brookfield Viscometer was operated according to
ASTM D5133. 25 ml to 30 ml of the sample was poured into a glass
stator to the fill line, which was immersed into an oil bath. The
oil bath was programmed to cool from -5.degree. C. to -40.degree.
C. at 1.degree. C./hour scanning speed. The sample was preheated to
90.degree. C. for 90 minutes to remove thermal history. The
temperature ramping program was set to cool from -5.degree. C. to
-40.degree. C. at 1.degree. C./hour scanning speed. In sample
collection mode, the Gelation Index (GI) and maximum viscosity can
be viewed. The torque versus temperature data set can be converted
to a viscosity-temperature plot at which a gelation point and/or
corresponding gelation index can be established.
[0140] Melt Index (MI) was measured according to ASTM D1238 at
190.degree. C. under a 2.16 kilogram load.
[0141] Melt Flow Rate (MFR) was measured according to ASTM D1238 at
230.degree. C. under a 2.16 kilogram load or a 21.6 kilogram
load.
[0142] Thickening Efficiency (TE) was determined according to ASTM
D445.
[0143] Shear Stability index (SSI) was determined according to ASTM
D6278 at 30 and 90 cycles using a Kurt Orbahn machine.
[0144] Shear stress data was accomplished by first heating the
sample to -15.degree. C., and waiting for 15 minutes. Then while
measuring the shear stress, applying a logarithmically increasing
strain by varying the shear rate logarithmically from 10.sup.-3 to
10 with 20 points/decade and 1 second per point.
[0145] The number of branch points was determined by measuring the
radius of gyration of polymers as a function of the molecular
weight by the methods of size exclusion chromatography augmented by
laser light scattering. These procedures are described in the
publications "A Study of the Separation Principle in Size Exclusion
Chromatography" by T. Sun, R. R. Chance, W. W. Graessley and D. J.
Lohse in the journal MACROMOLECULES, 2004, Volume 37, Issue 11, pp.
4304-4312, and "Effect of Short Chain Branching on the Coil
Dimensions of Polyolefins in Dilute Solution" by T. Sun, R. R.
Chance, W. W. Graessley and P. Brant in the journal MACROMOLECULES,
2001, Volume 34, Issue 19, pp. 6812-6820, which are incorporated by
reference herein.
[0146] Branching in polymers having narrow, and most probably, low
polydispersity index with essentially uniform intramolecular and
intermolecular distribution of composition can also be described by
the ratio of the TE to the MFR@230.degree. C. measured at a load of
2.16 Kg. High values of this parameter indicate low levels of
branching while low levels indicate substantial levels of
branching.
[0147] Intermolecular composition distribution, unlike CDBI,
contemplates weight percent of copolymer content within a smaller
range from a median total molar comonomer content, e.g., within 25
wt % of median. For example, for a Gaussian compositional
distribution, 95.5% of the polymer, used herein for this example as
"Polymer Fraction", is within 20 wt % ethylene of the mean if the
standard deviation is 10%. The intermolecular composition
distribution for the Polymer Fraction is 20 wt % ethylene for such
a sample, i.e., 10% standard deviation yields 20 wt %
intermolecular composition distribution.
[0148] Compositional Heterogeneity, both intermolecular-CD and
intramolecular-CD can be determined by carbon-13 NMR. Conventional
techniques for measuring intermolecular-CD and intramolecular-CD
are described in MACROMOLECULES, H. N. Cheng, Masahiro Kakugo,
entitled "Carbon-13 NMR analysis of compositional heterogeneity in
ethylene-propylene copolymers," Volume 24, Issue 8, pp. 1724-1726,
(1991), and in the publication MACROMOLECULES, C. Cozewith,
entitled "Interpretation of carbon-13 NMR sequence distribution for
ethylene-propylene copolymers made with heterogeneous catalysts,"
Volume 20, Issue 6, pp. 1237-1244, (1987).
[0149] Generally, conventional carbon-13 NMR measurements of diad
and triad distribution is used to characterize the ethylene-based
copolymer. Any conventional technique for measuring carbon-13 NMR
may be utilized. For example, ethylene-based copolymer samples are
dissolved in a solvent, e.g., trichlorobenzene at 4.5 wt %
concentration. The carbon-13 NMR spectra are obtained at elevated
temperature, e.g., 140.degree. C., on a NMR spectrometer at 100
MHz. An exemplary spectrometer is a pulsed Fourier transform Varian
XL-400 NMR spectrometer. Deuteriated o-dichlorobenezene is placed
in a coaxial tube to maintain an internal lock signal. The
following instrument conditions are utilized: pulse angle,
75.degree.; pulse delay, 25 second; acquisition time, 0.5 second,
sweep width, 16000 Hz. The carbon-13 NMR peak area measurements
were determined by spectral integration. Diad and triad
concentrations were calculated from the equations presented in
MACROMOLECULES, Kakugo et al., Volume 15, Issue 4, pp. 1150-1152,
(1982). The diad and triad concentrations were then normalized to
give a mole fraction distribution. Polymer composition was
calculated from the methane peaks, the methylene peaks, and the
diad balance. These values may be considered individually or an
average of the three values may be utilized. Unless stated
otherwise, this application utilizes an average of these three
values. The results are then compared to conventional model
equations as disclosed in the above references.
[0150] One aspect of these measurements involves the determination
of the reactivity ratios (r.sub.1r.sub.2) of the polymerization
system for the ethylene-based polymers according to the procedures
in the publication. Polymers that have a compositional
heterogeneity, either intramolecular or intermolecular, have a much
larger reactivity ratio than the polymers that have only a small or
negligible amount.
[0151] Without being limited to theory or one method of
calculation, it is believed that an one exemplary model for, so
called ideal copolymerizations, is described by the terminal
copolymerization model:
m=M(r.sub.1M+1)/(r.sub.2+M) (1)
wherein r.sub.1 and r.sub.2 are the reactivity ratios, m is the
ratio of monomers in the copolymer, m.sub.1/m.sub.2, M is the ratio
of monomers in the reactor, M.sub.1/M.sub.2, and the diad and triad
concentrations follow first order Markov statistics. For this
model, nine equations are derived that related to the diad and
triad concentrations P.sub.12 and P.sub.21, the probability of
propylene adding to an ethylene-ended chain, and the probability of
propylene adding to a propylene-ended chain, respectively. Thus a
fit of carbon-13 NMR data to these equations yields P.sub.12 and
P.sub.21 as the model parameters from which r.sub.1 and r.sub.2 can
be obtained from the relationships:
r.sub.1M=(1-P.sub.12)/P.sub.12
r.sub.2/M=(1-P.sub.21)/P.sub.21
[0152] The corresponding equations for random copolymerizations
with r.sub.1r.sub.2=1 can also be used to simplify equation (1),
above, to m=r.sub.1M. The ethylene fraction in the polymer, E, is
equal to 1-P.sub.12. This allows the diad and triad equations to be
written in terms of polymer composition:
EE=E.sup.2
EE=2E(1-E)
PP=(1-E).sup.2
EEE=E.sup.3
EEP=2E.sup.2(1-E)
EPE=E.sup.2(1-E)
PEP=E(1-E).sup.2
PPE=2E(1-E).sup.2
PPP=(1-E).sup.3
[0153] Variations and extensions of these equations are provided in
the references incorporated herein, including use of catalysts with
different active sites, equations for estimating the number of
catalyst species present, or complex models such as those with
three or more species present, etc.
[0154] From these modeling equations, and those equations presented
by MACROMOLECULES, C. Cozewith, Ver Strate, Volume 4, pp. 482-489,
(1971), the average values of r.sub.1, r.sub.2, and r.sub.1r.sub.2
arising from the copolymerization kinetics are given by:
r.sub.1=(.SIGMA.r.sub.1if.sub.i/G.sub.i)/(.SIGMA.f.sub.i/G.sub.i)
r.sub.2=(.SIGMA.r.sub.2if.sub.i/G.sub.i)/(.SIGMA.f.sub.i/G.sub.i)
r.sub.1r.sub.2=(.SIGMA.r.sub.1if.sub.i/G.sub.i)(.SIGMA.r.sub.2if.sub.i/-
G.sub.i)/(.SIGMA.f.sub.i/G.sub.i).sup.2 [0155] where
G.sub.i=r.sub.1iM.+-.2+r.sub.2i/M These equations and the models
presented in the references cited above may be utilized by those
skilled in the art to characterize the ethylene-based copolymer
composition distribution.
[0156] Further information and techniques for measuring
intramolecular-CD are found in MACROMOLECULES, Randel, James C.,
Volume 11, Issue 1, pp. 33-36, (1978), MACROMOLECULES, Cheng, H.
N., Volume 17, Issue 10, pp. 1950-1955, (1984), and MACROMOLECULES,
Ray, G. Joseph, Johnson, Paul E., and Knox, Jack R., Volume 10
Issue 4, pp. 773-778, (1977), which are incorporated by reference
herein. Such techniques are readily known to those skilled in the
art of analyzing and characterizing olefin polymers.
[0157] Temperature Rising Elution Fractionation (TREF). The
determination of intermolecular compositional heterogeneity was
determined by the fractionation of the EP copolymer carried out by
a Polymer Char TREF 200 based on a well-known principle that the
solubility of a semi-crystalline copolymer is a strong function of
temperature. A corresponding method is described in U.S. Pat. No.
5,008,204. The instrument is a column packed with solid
stainless-steel beads. The copolymer of interest was dissolved in
1,2 ortho-dichlorobenzene (oDCB) at 160.degree. C. for 60 min. Half
of a milliliter (ml) of the polymer solution (concentration=4-5
mg/ml) was injected in the column and it was stabilized there at
140.degree. C. for 45 min. The solution was cooled from 140.degree.
C. to -15.degree. C. at 1.degree. C./min and equilibrated at this
temperature for 10 min. This caused the copolymer to crystallize
out of the quiescent solution in successive layers of decreasing
crystallinity onto the surface of the beads. Pure solvent (oDCB)
was pumped for 5 min at -15.degree. C. at a flow rate of 1 ml/min
through an infrared detector. A valve was then switched to allow
this chilled oDCB to flow through the column at the same flow rate
at -15.degree. C. for 10 min. The material eluted was designated as
the soluble fraction of the copolymer. At this point, the heater
was on and the solvent continued to flow through both the column
and the infrared detector while the temperature was programmed
upward at a controlled rate of 2.degree. C./min to 140.degree. C.
The infrared detector continuously measured the concentration of
the copolymer in the effluent from the column, and a continuous
solubility distribution curve was obtained.
[0158] Described below are further embodiments of the inventions
provided herein:
A. A polymer blend composition comprising a first ethylene-based
copolymer and a second ethylene-based copolymer, wherein the first
copolymer has an ethylene content from about 44 to about 52 wt %;
the second copolymer has an ethylene content from about 68 to about
75 wt %; the first and second copolymers have a weight-average
molecular weight (Mw) less than or equal to about 130,000; the
ratio of the melt index of the first copolymer to the melt index of
the second copolymer is less than or equal to about 3.0; and the
composition comprises from about 35 to about 65 wt % of the first
copolymer, based on the total weight of the first and second
copolymers. B. The polymer blend composition of paragraph A,
wherein the first copolymer has an ethylene content from about 45
to about 51 wt % and the second copolymer has an ethylene content
from about 69 to about 74 wt %. C. The polymer blend composition of
any of paragraphs A and B, wherein the first copolymer has an
ethylene content from about 46 to about 50 wt %, and the second
copolymer has an ethylene content from about 70 to about 73 wt %.
D. The polymer blend composition of any of paragraphs A through C,
wherein the first and second copolymers each comprise one or more
comonomers selected from the group consisting of C.sub.3-C.sub.20
alpha-olefins. E. The polymer blend composition of any of
paragraphs A through D, wherein the ethylene content of the second
copolymer is at least about 17 wt % greater than the ethylene
content of the first copolymer. F. The polymer blend composition of
any of paragraphs A through E, wherein the ethylene content of the
second copolymer is at least about 21 wt % greater than the
ethylene content of the first copolymer. G. The polymer blend
composition of any of paragraphs A through F, wherein the
composition comprises from about 38 to about 62 wt % of the first
copolymer, based on the total weight of the first and second
copolymers. H. The polymer blend composition of any of paragraphs A
through G, wherein the composition comprises from about 40 to about
60 wt % of the first copolymer, based on the total weight of the
first and second copolymers. I. A polymer blend composition
comprising a first ethylene-based copolymer and a second
ethylene-based copolymer, wherein the first copolymer has a heat of
fusion from about 0 to about 15 J/g; the second copolymer has a
heat of fusion from about 40 to about 65 J/g; the first and second
copolymers have a weight-average molecular weight (Mw) less than or
equal to about 130,000; the ratio of the melt index of the first
copolymer to the melt index of the second copolymer is less than or
equal to about 3.0; and the composition comprises from about 35 to
about 65 wt % of the first copolymer, based on the total weight of
the first and second copolymers. J. The polymer blend composition
of any of paragraphs A through I, wherein the first copolymer has a
heat of fusion from about 0 to about 10 J/g and the second
copolymer has a heat of fusion from about 42 to about 62 J/g. K.
The polymer blend composition of any of paragraphs A through J,
wherein the first copolymer has a heat of fusion from about 0 to
about 5 J/g and the second copolymer has a heat of fusion from
about 45 to about 60 J/g. L. The polymer blend composition of any
of paragraphs A through K, wherein the first and second copolymers
each comprise one or more comonomers selected from the group
consisting of C.sub.3-C.sub.20 alpha-olefins. M. The polymer blend
composition of any of paragraphs A through L, wherein the ethylene
content of the second copolymer is at least about 17 wt % greater
than the ethylene content of the first copolymer. N. The polymer
blend composition of claim 1 any of paragraphs A through M, wherein
the ethylene content of the second copolymer is at least about 21
wt % greater than the ethylene content of the first copolymer. O.
The polymer blend composition of any of paragraphs A through N,
wherein the composition comprises from about 38 to about 62 wt % of
the first copolymer, based on the total weight of the first and
second copolymers. P. The polymer blend composition of any of
paragraphs A through O, wherein the composition comprises from
about 40 to about 60 wt % of the first copolymer, based on the
total weight of the first and second copolymers. Q. A lubricating
oil composition comprising a lubricating oil basestock, a first
ethylene-based copolymer, and a second ethylene-based copolymer,
wherein the first copolymer has an ethylene content from about 44
to about 52 wt %; the second copolymer has an ethylene content from
about 68 to about 75 wt %; the first and second copolymers have a
weight-average molecular weight (Mw) less than or equal to about
130,000; the ratio of the melt index of the first copolymer to the
melt index of the second copolymer is less than or equal to about
3.0; and the composition comprises from about 35 to about 65 wt %
of the first copolymer, based on the total weight of the first and
second copolymers. R. The lubricating oil composition of paragraph
Q, wherein the first copolymer has an ethylene content from about
46 to about 50 wt %, and the second copolymer has an ethylene
content from about 70 to about 73 wt %. S. The lubricating oil
composition of any of paragraphs Q and R, wherein the first and
second copolymers each comprise one or more comonomers selected
from the group consisting of C.sub.3-C.sub.20 alpha-olefins. T. The
lubricating oil composition of any of paragraphs Q through S,
wherein the ethylene content of the second copolymer is at least
about 21 wt % greater than the ethylene content of the first
copolymer. U. A lubricating oil composition comprising a
lubricating oil basestock, a first ethylene-based copolymer, and a
second ethylene-based copolymer, wherein the first copolymer has a
heat of fusion from about 0 to about 15 J/g; the second copolymer
has a heat of fusion from about 40 to about 65 J/g; the first and
second copolymers have a weight-average molecular weight (Mw) less
than or equal to about 130,000; the ratio of the melt index of the
first copolymer to the melt index of the second copolymer is less
than or equal to about 3.0; and the composition comprises from
about 35 to about 65 wt % of the first copolymer, based on the
total weight of the first and second copolymers. V. The lubricating
oil composition of any of paragraphs Q through U, wherein the first
copolymer has a heat of fusion from about 0 to about 5 J/g and the
second copolymer has a heat of fusion from about 45 to about 60
J/g. W. The lubricating oil composition of any of paragraphs Q
through V, wherein the first and second copolymers each comprise
one or more comonomers selected from the group consisting of
C.sub.3-C.sub.20 alpha-olefins. X. The lubricating oil composition
of any of paragraphs Q through W, wherein the ethylene content of
the second copolymer is at least about 21 wt % greater than the
ethylene content of the first copolymer.
EXAMPLES
Preparation of the Ethylene-Based Copolymers
[0159] A variety of ethylene-based copolymers as described above
were synthesized as follows. Ethylene and propylene were
polymerized in solution in a continuous stirred tank reactor, using
hexane as a solvent. Polymerization in the reactor was performed at
a temperature of about 110-115.degree. C., an overall pressure of
about 20 bar, and ethylene and propylene feed rates of about 1.3
and 2.0 kg/hr, respectively. N,N-dimethylanilinium
tetrakis(pentafluorophenyl)boron was used to activate
di(p-triethylsilylphenyl)methenyl
[cyclopentadienyl)(2,7-di-tert-butylfluorophenyl)]hathium dimethyl
as the catalyst. During the polymerization process, hydrogen
addition and temperature control were used to achieve the desired
melt flow rate. The catalyst, activated externally to the reactor,
was added as needed in amounts effective to maintain the target
polymerization temperature.
[0160] The copolymer solution exiting the reactor was stopped from
further polymerization by the addition of water and then
devolatilized using conventional techniques such as, for example,
flashing or liquid phase separation, first by removing the bulk of
the hexane to provide a concentrated solution, then by stripping
the remainder of the solvent in anhydrous conditions using a
devolatilizer or a twin screw devolatilizing extruder so as to
result in a molten polymer composition comprising less than 0.5 wt
% solvent and other volatiles. The molten polymer was cooled until
solid.
[0161] The compositions and other properties of the polymers thus
prepared are set forth in Table 1. Polymers that meet the
description of the first ethylene-based copolymer as described
above are designated "A" and polymers that meet the description of
the second ethylene-based copolymer as described above are
designated "B."
TABLE-US-00002 TABLE 1 A1 A2 A3 A4 B1 B2 B3 B4 B5 B6 Mw, g/mol
92958 96720 100016 110133 74883 65983 73675 94434 77890 80194 Mw/Mn
2.25 2.20 2.22 2.03 2.28 2.23 2.08 2.23 2.24 2.18 C.sub.2, wt %
48.98 45.65 46.00 49.94 70.41 72.57 72.44 76.42 66.82 79.28 MFR,
g/10 min 5.53 5.97 5.61 2.90 6.40 8.32 6.61 1.49 4.99 2.64 (2.16
kg, 230.degree. C.) Tm,.degree. C. (1.sup.st melt) -35.0 n/a n/a
-34.3 43.6 44.8 44.3 48.6 15.0 55.5 Hf, J/g (1.sup.st melt) 0.4 n/a
n/a 2.1 45.0 58.5 52.4 70.4 44.0 73.6 Tc, .degree. C. (2.sup.nd
cool) -50.6 n/a n/a -48.1 14.6 18.5 18.1 37.9 11.6 44.6 Hc, J/g
(2.sup.nd cool) 2.4 n/a n/a 3.4 46.4 52.1 43.8 61.4 36.2 59.6 Tm,
.degree. C. (2.sup.nd melt) -36.4 n/a n/a -35.0 19.2 30.2 29.9 48.5
11.0 53.8 Hf, J/g (2.sup.nd melt) 0.6 n/a n/a 2.3 46.5 51.2 51.1
63.5 43.3 67.9 Tg, .degree. C. -58.6 -57.5 -57.6 -58.3 -48.1 -45.0
-37.1 -40.3 -48.1 -40.3
Examples 1-115
[0162] Polymer blend compositions were prepared comprising a first
ethylene-based copolymer and a second ethylene based copolymer,
both of which were selected from the polymers listed in Table 1.
The blends were made by melt blending in a Brabender mixer having
an internal cavity of 250 ml at a temperature of from about 120 to
about 150.degree. C. for 3 to 5 minutes using low shear blades
rotating at a speed of 15 to 200 rpm. The ethylene-based copolymers
were protected during the mixing operation with a nitrogen blanket
and by the addition of 1000 ppm of a 3:1 mixture of Irganox 1076
and Irgafos 168 (both available from BASF Corporation) before
blending. The compositions of the resulting polymer blends are set
forth in Table 2 below, and the amounts of each component are given
in grams.
TABLE-US-00003 TABLE 2 Example No. A1 A2 A3 A4 B1 B2 B3 B4 B5 B6 1
160 240 2 160 240 3 160 240 4 200 200 5 200 200 6 200 200 7 240 160
8 240 160 9 240 160 10 280 120 11 280 120 12 280 120 13 320 80 14
320 80 15 320 80 16 160 240 17 160 240 18 160 240 19 200 200 20 200
200 21 200 200 22 240 160 23 240 160 24 240 160 25 280 120 26 280
120 27 280 120 28 320 80 29 320 80 30 320 80 31 160 240 32 160 240
33 160 240 34 200 200 35 200 200 36 200 200 37 240 160 38 240 160
39 240 160 40 280 120 41 280 120 42 280 120 43 320 80 44 320 80 45
320 80 46 160 240 47 160 240 48 160 240 49 200 200 50 200 200 51
200 200 52 240 160 53 240 160 54 240 160 55 280 120 56 280 120 57
280 120 58 320 80 59 320 80 60 320 80 61 160 240 62 160 240 63 160
240 64 200 200 65 200 200 66 200 200 67 240 160 68 240 160 69 240
160 70 280 120 71 280 120 72 280 120 73 320 80 74 320 80 75 320 80
76 160 240 77 160 240 78 160 240 79 200 200 80 200 200 81 200 200
82 240 160 83 240 160 84 240 160 85 280 120 86 280 120 87 280 120
88 320 80 89 320 80 90 320 80 91 160 240 92 160 240 93 160 240 94
200 200 95 200 200 96 200 200 97 240 160 98 240 160 99 240 160 100
280 120 101 280 120 102 280 120 103 320 80 104 320 80 105 320 80
106 160 240 107 160 240 108 200 200 109 200 200 110 240 160 111 240
160 112 280 120 113 280 120 114 320 80 115 320 80
[0163] Molecular weight, thermal properties, and other
characteristics of the polymer blends of Examples 1-115 are given
in Table 3, below.
TABLE-US-00004 TABLE 3 MFR, g/10 min DSC: 1.sup.st Heat DSC:
2.sup.nd Heat Ex. (2.16 kg, Mw, Mw/ Tm, Hf, Tm, Hf, Tm, .degree. C.
Tg, No. 230.degree. C.) FTIR g/mol Mn .degree. C. J/g .degree. C.
J/g (onset) .degree. C. 1 2.52 64.05 95093 2.28 2 6.95 61.37 79671
2.34 3 5.71 58.47 83858 2.31 4 2.87 60.82 94642 2.26 5 6.86 57.59
81822 2.33 6 5.87 56.47 85255 2.28 7 3.34 58.09 94529 2.29 8 6.43
54.90 85279 2.29 43.3 20.2 29.9 23.7 -43.8 -27.1 9 5.75 54.27 87204
2.26 43.3 21.1 20.7 23.1 -49.4 -57 10 3.87 54.96 96128 2.21 46.4
15.2 48.4 12.5 0.03 -55.8 11 6.38 53.29 89363 2.31 43.4 17.4 32.2
15.6 -38.6 -57.4 12 5.82 51.87 91674 2.26 43.4 10.4 32 10.2 -33.3
-57.1 13 4.48 51.71 98892 2.19 46.8 13.5 48.3 10.5 -21.7 -57.3 14
6.23 50.37 93073 2.22 43.6 9.2 32.7 6.8 -23.2 -57.5 15 5.72 49.71
94320 2.29 n/a n/a 16.7 10.1 -49.6 -57.4 16 2.61 63.98 94969 2.27
47.4 35.8 48.8 33.6 -20.6 -57 17 7.23 61.15 78927 2.27 43.5 32.4
32.5 27.1 -28.6 -57 18 6.32 59.28 81765 2.31 22.3 49.7 22.4 22.6
-35.3 -57.2 19 2.99 60.78 95133 2.19 46.5 38.7 47.9 32.9 -31.2
-56.8 20 7.18 58.06 81095 2.26 43.5 40.7 33.6 18.8 -14 -56.9 21
6.06 56.84 84432 2.30 43.8 26.0 27.4 15.9 -17.6 -57.0 22 3.47 57.76
96930 2.18 47.1 27.7 47.7 26.5 -28.8 -56.8 23 7.05 56.22 93627 2.34
43.5 18.1 32.2 19.6 -36.5 -57.1 24 6.44 54.63 85046 2.31 44.1 19.9
24.8 12.7 -26.7 -56.9 25 4.14 55.21 96796 2.22 47.4 26.5 47.0 16.5
-22.8 -57.0 26 6.88 53.23 86536 2.31 44.0 15.8 31.1 15.5 -39.3
-57.0 27 6.33 52.21 88950 2.22 43.4 14.3 22.9 9.0 -29.9 -57.2 28
4.84 51.97 96810 2.22 47.6 12.9 48.5 10.6 4.4 -57.2 29 6.71 50.94
89667 2.29 44.1 8.7 36.7 5.2 1.3 -57.3 30 6.49 49.56 89962 2.23
43.7 6.6 21.4 5.9 -38.9 -57.0 31 2.51 65.43 93794 2.18 46.9 31.5
48.9 28.8 -13 -57.8 32 7.30 63.36 76288 2.30 44.3 35.4 31.6 31.7
-36.3 -58.0 33 5.88 61.14 79103 2.26 18.8 36.3 19.3 27.1 -39.9
-57.7 34 2.91 62.77 119213 2.55 47 47.6 48.3 31.5 -26.5 -58.1 35
7.17 60.96 78222 42.8 44.8 32.6 28.6 -35.4 -57.6 36 6.08 58.66
82102 2.24 43.4 28.9 21.3 22.6 -40.9 -57.9 37 3.49 60.28 95618 2.23
47.6 40.2 49.1 18.6 -5.7 -57.8 38 6.59 58.63 81354 2.29 43.6 23.1
31.4 20.9 -41.1 -58 39 5.62 57.10 82973 2.26 45.2 20.9 20.3 18.7
-45.2 -58 40 3.91 57.68 95467 2.20 46.9 21 48.5 13.9 -3.6 -58.3 41
6.19 55.99 82554 2.23 43.2 14.6 32.3 10.8 -22.8 -58.2 42 6.08 54.55
84467 2.26 43.3 13.0 22.1 11.5 -40.6 -58.1 43 4.55 54.58 94512 2.28
46.8 12.5 48.4 11.8 -46.9 -58.2 44 6.14 53.85 85698 2.27 44.5 13.3
33.0 8.0 -41.5 -58.0 45 6.11 52.53 90563 2.18 44.1 7.7 18.5 10.0
-51.3 -58.4 46 1.91 64.32 94846 2.31 46.2 38 47.7 45.2 -40.4 -57.7
47 4.46 59.91 85782 2.23 47.0 34.0 -41.0 48 4.32 58.93 84834 2.42
49 2.11 61.71 99282 2.23 46.0 38.2 47.0 34.0 -41.0 -57.9 50 4.27
58.71 89631 2.28 51 4.24 57.66 89587 2.24 52 2.34 59.13 99203 2.21
45.9 26.5 48.5 24.4 -42.0 -57.9 53 56.20 93288 2.12 54 55.70 90920
2.36 55 56.57 100524 2.15 47.8 19.2 47.8 19.2 -44.5 -58.0 56 54.29
95962 2.19 57 4.34 54.64 95549 2.27 58 2.54 54.10 102038 2.19 47.3
17.8 47.3 17.8 -51.9 -58.0 59 3.32 52.39 99714 2.24 60 3.28 52.48
97990 2.23 61 3.85 65.17 85288 2.07 62 5.86 59.99 78486 2.14 63
5.52 57.64 82261 2.14 64 4.06 62.08 88459 2.09 65 5.99 57.14 88095
2.05 66 5.50 55.09 80126 2.14 67 4.44 59.12 84846 2.16 68 6.00
54.14 87994 2.07 69 4.75 52.93 84369 2.15 70 4.68 55.09 86641 2.11
71 5.64 51.02 87145 2.13 72 5.64 50.87 92196 1.99 73 5.05 52.30
91295 2.11 74 5.86 49.93 88464 2.14 75 5.65 49.22 89994 2.02 76
3.92 64.18 83998 2.14 77 6.22 58.65 79938 2.09 78 5.49 56.56 82872
2.09 79 4.23 61.11 87868 2.17 80 5.98 57.13 83214 2.27 51.5 38.3
53.9 31.8 -17.9 -56.8 81 5.65 54.04 87118 2.17 45.2 26.7 28.8 20.6
-31.5 -57.1 82 4.60 58.48 89933 2.07 18.1 18 12.9 16.7 -39.7 -57.1
83 6.08 54.23 86110 2.16 50.6 31.2 53.9 26 -17.2 -57.1 84 5.67
52.03 88439 2.13 44.9 21 29.3 17.4 -33.3 -57.2 85 4.92 56.34 17.7
15.9 14.4 14.8 -42.7 -57.3 86 6.50 52.02 87648 2.12 87 5.87 50.95
88328 2.25 45.8 13.7 29.9 13 -35.6 -57.3 88 5.49 52.12 89 6.29
49.86 90 6.06 49.03 91 3.82 65.26 92 5.90 60.18 93 5.24 58.11 94
4.10 62.43 85077 2.27 50.4 41.1 53.9 33.6 -23.8 -58 95 5.98 57.88
80693 2.28 43.5 26.8 28.5 28.6 -45.1 -57.8 96 5.48 56.39 85583 2.21
17.5 26.2 13.4 21.1 -45.4 -58 97 4.33 59.72 86157 2.18 49.4 30.4
53.9 22.5 -5 -58.1 98 5.88 55.99 83169 2.24 43.6 18.2 27.9 21 -43.1
-58.1 99 5.66 53.97 84973 2.21 17.8 13.4 13.9 14.1 -45.1 -58.1 100
4.72 56.91 87276 2.17 49.3 21.4 52.8 20 -34.6 -58.3 101 5.87 53.6
85803 2.17 44.4 13.8 28 16.1 -47.1 -58.3 102 5.65 52.59 88254 2.18
17.4 11.2 14.7 11.7 -48.7 -58.1 103 5.02 54.74 104 6.01 52.28 105
5.73 52.14 106 4.10 57.75 88340 2.18 19.6 22.9 9.8 19.8 -44 -57.6
107 2.91 65.82 89295 2.16 51 40.5 53.6 39.5 -28.8 -57.9 108 3.74
57.37 17 20.1 14.4 17.2 -44 -57.8 109 2.94 59.61 49.7 35.6 53.4
29.2 12.8 -57.8 110 3.73 54.75 17.2 14.5 14.7 15.9 -47.6 -57.8 111
2.92 59.03 47.4 23.5 53.5 24.9 -32.2 -57.9 112 3.52 53.3 17.1 9.7
13.9 14.4 -50.9 -58.1 113 3.04 58.21 49.1 25 53 22.4 -45.3 -58.1
114 3.34 51.24 97683 2.19 -33.5 8.7 -34 8.6 -52.5 -58.2 115 3.01
54.53 100152 2.15 52 16.7 53 15.5 -49.6 -58.3
[0164] Tables 2 and 3 demonstrate the diversity in composition and
crystallinity of the ethylene-based copolymer blends of the
invention.
Examples 116-220
[0165] 10W-50 lubricating oil compositions were prepared
sequentially comprising the ethylene-based copolymer blends of
Examples 1-115. Thus Example 116 comprises the formulation based on
the Polymer blend of Example 1, while Example 117 comprises the
formulation based on Example 2. In general in the data in Table 4
only the formulation data for Example (115+x) comprises the polymer
blend in Example x. All of the lubricating oil formulations
comprised the following: 52 g of a group 11 lubricating oil
basestock having a viscosity of 4.5 cSt, 30.6 g of a group 11
lubricating oil basestock having a viscosity of 6.1 cSt, 1.4 g of
the inventive polymer blend composition of one of Examples 1-115,
14 g of an additive package (Infineum D3426), 0.7 g of a magnesium
sulfonate additive having a base number of 400 (Infineum 9340), 1.0
g of a calcium sulfonate additive having a base number of 300
(Infineum 9330), and 0.3 g of a pour point depressant (Infineum
V387). Viscosity characteristics of the resulting compositions were
tested as follows. Kinematic viscosity (KV) at 100.degree. C. was
determined according to ASTM D445-5. Apparent viscosity was
measured using a cold cranking simulator (CCS) at -20.degree. C.
and -25.degree. C. according to ASTM D5293-4 and ASTM D5293-5,
respectively. Yield stress and viscosity were determined using a
mini rotary viscometer (MRV) at -25.degree. C. and -30.degree. C.
according to ASTM D4684-4 (-25.degree. C.) and ASTM D4684-5
(-30.degree. C.). Results of these tests are reported in Table 4,
below.
TABLE-US-00005 TABLE 4 Ex. KV, cSt CCS, CCS, Yield Stress, MRV
Visc., Yield Stress, MRV Visc., Pour Point, No. (100.degree. C.) cP
(-20.degree. C.) cP (-25.degree. C.) MRV (-25.degree. C.) cP
(-25.degree. C.) MRV (-30.degree. C.) cP (-30.degree. C.) .degree.
C. 116 20.81 3350 6750 <35 15700 <35 53800 -34 117 18.03 3340
6750 <35 13400 <35 36600 -35 118 18.45 3330 6220 <35 16500
<35 52300 -35 119 20.64 3420 6800 <35 16600 <35 45700 -39
120 18.42 3380 6710 <35 15400 <35 43400 -37 121 18.71 3390
6420 <35 17300 <35 48000 -35 122 20.55 3470 6890 <35 18200
<35 52600 -36 123 18.22 3460 6780 <35 14600 <35 40900 -37
124 18.78 3370 6750 <35 16800 <35 47900 -37 125 19.89 3470
6900 <35 16900 <35 51100 -37 126 18.77 3470 6690 <35 16700
<35 47000 -40 127 18.85 3470 6750 <35 17200 <35 43200 -36
128 19.47 3540 7040 <35 18600 <35 53900 -39 129 19.20 3540
7020 <35 17800 <35 49300 -38 130 19.63 3740 7420 <35 19100
<35 53600 -40 131 20.28 3290 6530 <35 14800 <35 45100 -34
132 17.75 3300 6660 <35 13600 <35 38700 -36 133 18.02 3280
6450 <35 15300 <35 44100 -36 134 19.90 3360 6700 <35 14600
<35 43000 -37 135 17.88 3340 6640 <35 13800 <35 38900 -37
136 18.30 3330 6290 <35 15500 <35 44700 -37 137 19.75 3400
6780 <35 16200 <35 46400 -38 138 18.15 3390 6670 <35 15000
<35 40800 -38 139 18.89 3410 6440 <35 16700 <35 43300 -36
140 19.49 3470 6810 <35 16700 <35 44500 -36 141 18.34 3430
6740 <35 16000 <35 41400 -36 142 18.40 3430 6710 <35 16200
<35 42400 -37 143 19.13 3540 6860 <35 17400 <35 44300 -37
144 18.53 3490 6840 <35 16800 <35 43200 -38 145 18.52 3490
6650 <35 17200 <35 41900 -38 146 20.15 3260 6600 <35 13600
<35 39100 -39 147 18.09 3310 6640 <35 13000 <35 34800 -37
148 18.20 3260 6500 <35 14900 <35 38300 -43 149 20.47 3340
6720 <35 14400 <35 40800 -37 150 17.90 3310 6680 <35 13600
<35 34700 -41 151 18.43 3310 6580 <35 15300 <35 39200 -35
152 19.92 3360 6740 <35 14800 <35 39700 -38 153 18.10 3370
6730 <35 14700 <35 35400 -42 154 18.56 3360 6590 <35 15800
<35 39600 -39 155 19.91 3430 6840 <35 15700 <35 41500 -41
156 18.29 3420 6740 <35 15500 <35 40000 -43 157 18.24 3410
6680 <35 16000 <35 41400 -38 158 19.31 3520 6900 <35 16600
<35 44500 -40 159 18.46 3480 6850 <35 16300 <35 43200 -42
160 18.62 3500 6850 <35 17000 <35 44100 -38 161 20.51 3090
6300 <35 13400 <35 35900 -38 162 17.69 3100 6300 <35 12300
<35 31200 -37 163 18.11 3090 6310 <35 14700 <35 40500 -35
164 20.09 3140 6510 <35 13800 <35 37600 -37 165 17.9 3120
6430 <35 13700 <35 35100 -37 166 18.32 3160 6390 <35 15400
<35 41200 -35 167 19.99 3200 6510 <35 14800 <35 40300 -37
168 18.25 3190 6440 <35 14400 <35 37500 -37 169 18.38 3210
6430 <35 14700 <35 39800 -37 170 19.76 3270 6580 <35 15000
<35 39700 -38 171 18.45 3240 6510 <35 14900 <35 37700 -36
172 18.65 3280 6520 <35 41600 <35 41600 -35 173 19.48 3350
6680 <35 16000 <35 42200 -37 174 18.66 3310 6610 <35 16200
<35 41800 -38 175 18.70 3320 6640 <35 16600 <35 43000 -38
176 19.26 3340 6740 <70 20800 <105 78700 -37 177 19.24 3360
6800 <35 20800 <70 75200 -36 178 19.00 3380 6870 <35 19500
<35 63900 -34 179 18.96 3420 6890 <35 18300 <35 53800 -35
180 19.24 3500 6980 <35 18600 <35 52300 -36 181 19.65 3230
6710 <35 18700 <70 73700 -33 182 18.59 3230 6580 <35 14500
<35 47000 -34 183 19.33 3340 6760 <70 20900 <105 75700 -33
184 19.02 3310 6600 <35 16600 <70 49400 -36 185 18.49 3300
6500 <35 14300 <35 38400 -38 186 18.60 3410 6710 <35 17100
<70 49700 -37 187 19.28 3410 6750 <35 16900 <35 48100 -37
188 18.41 3360 6530 <35 14600 <35 37300 -38 189 19.11 3480
6620 <35 17600 <35 48000 -37 190 19.22 3400 6730 <35 17300
<35 48600 -37 191 18.54 3440 6500 <35 15900 <35 41000 -37
192 18.82 3530 6470 <35 17200 <35 45200 -39 193 19.66 3570
7000 <35 19400 <70 58400 -39 194 20.26 3340 6580 <35 17200
<35 53000 -38 195 19.85 3490 6600 <35 18700 <35 51100 -36
196 20.61 3430 6700 <35 17500 <35 49500 -40 197 20.10 3530
6840 <35 18600 <35 49100 -35 198 20.71 3480 6840 <35 18200
<35 47600 -33 199 19.15 3290 6690 <35 20100 <105 75500 -35
200 19.98 3220 6520 <35 18700 <70 75500 -38 201 20.21 3510
7100 <35 20000 <35 49800 -39 202 20.04 3460 6940 <35 18200
<35 53800 -41 203 19.39 3480 7070 <35 17600 <35 50900 -35
204 18.95 3430 6790 <35 16600 <35 41800 -38 205 19.11 3500
7000 <35 17400 <35 46800 -35 206 20.62 3280 6570 <35 15600
<35 54400 -33 207 19.13 3310 6560 <35 14800 <35 44900 -33
208 18.79 3350 6620 <35 16100 <35 45900 -32 209 20.62 3390
6760 <35 16900 <35 52400 -32 210 19.33 3300 6610 <35 15700
<35 44900 -32 211 19.14 3380 6730 <35 17000 <35 46600 -31
212 20.63 3450 6890 <35 17600 <35 52600 -34 213 19.38 3440
6710 <35 16700 <35 46800 -31 214 19.40 3460 6810 <35 17300
<35 47600 -30 215 20.74 3220 6650 <35 15600 <35 59200 -31
216 19.09 3270 6510 <35 14100 <35 50900 -31 217 18.46 3290
6550 <35 15000 <35 50200 -33 218 20.47 3520 6920 <35 17800
<35 52900 -31 219 19.68 3440 6860 <35 17500 <35 48900 -32
220 19.60 3500 6910 <35 17900 <35 48200 -34
Examples 221-318
[0166] Lubricating oil compositions were prepared comprising the
ethylene-based copolymer blends of Examples 1-115. All of the
lubricating oil formulations comprised 1 wt % of the ethylene-based
copolymer blend in a Group I basestock (Americas Core 150,
available from Imperial Oil Ltd.) having the following lubricant
properties: kinematic viscosity (KV) at 100.degree. C. (ASTM
D445-5) of 5.189 cSt, KV at 40.degree. C. (ASTM D445-3) of 29 cSt
(min), viscosity index (ASTM D2270) of 95 (min), flash point (ASTM
D92) of 210.degree. C. (min), pour point (ASTM D97) of -15.degree.
C. (max), and Noack volatility (ASTM D5800) of 20 wt % (max). For
each formulation, shear stability properties (reflected by the Kurt
Orbahn (KO) test at 30 and 90 cycles) and thickening efficiency
(TE) were measured. Results of these tests are reported in Table 5,
below.
TABLE-US-00006 TABLE 5 Blend No. from Example No. Table 2 KO (30
cycles) KO (90 cycles) TE 221 1 25.08 30.47 2.20 222 2 20.33 24.31
1.88 223 3 20.44 24.49 1.93 224 4 26.37 30.47 2.17 225 5 21.90
25.61 1.90 226 6 22.44 26.25 1.94 227 7 27.08 32.29 2.16 228 8
21.97 26.00 1.94 229 9 24.75 28.06 1.98 230 10 28.13 32.79 2.11 231
11 25.83 29.94 1.98 232 12 26.69 30.75 2.00 233 13 26.60 31.60 2.11
234 14 27.11 30.96 2.00 235 15 27.08 31.05 2.03 236 16 23.57 29.12
2.20 237 17 20.42 24.21 1.88 238 18 22.96 27.03 1.93 239 19 25.69
30.34 2.17 240 20 21.02 25.50 1.92 241 21 20.72 24.74 1.94 242 22
24.91 30.21 2.13 243 23 23.24 26.85 1.94 244 24 23.85 27.83 1.96
245 25 26.52 28.85 2.11 246 26 24.80 28.57 1.96 247 27 26.19 29.76
1.96 248 28 26.83 32.35 2.07 249 29 27.00 30.91 1.98 250 30 27.65
31.72 2.00 251 31 21.90 26.99 2.19 252 32 17.29 21.45 1.89 253 33
20.73 24.59 1.93 254 34 23.55 28.49 2.18 255 35 22.93 26.65 1.90
256 36 23.22 27.55 1.97 257 37 25.52 30.38 2.16 258 38 22.11 24.90
1.95 259 39 24.26 28.00 1.97 260 40 26.79 30.12 2.14 261 41 24.26
28.00 1.97 262 42 24.50 28.68 1.95 263 43 27.67 32.39 2.14 264 44
22.35 25.88 1.98 265 45 24.71 28.67 2.03 266 46 24.67 30.03 2.26
267 47 18.80 23.00 1.95 268 48 20.35 24.30 1.96 269 49 24.87 30.25
2.20 270 50 19.32 23.50 1.95 271 51 20.94 25.09 1.96 272 52 25.08
29.69 2.18 273 53 21.49 25.83 1.97 274 54 23.22 27.25 2.01 275 55
25.73 30.39 2.16 276 56 22.78 26.64 2.00 277 57 23.41 27.44 2.01
278 58 27.32 31.69 2.14 279 59 25.23 29.44 2.01 280 60 25.97 30.05
2.06 281 63 18.83 22.22 2.03 282 66 23.82 27.25 2.10 283 69 23.71
28.85 2.07 284 72 26.37 30.95 2.08 285 75 25.92 30.92 2.06 286 79
22.45 27.27 2.12 287 80 22.07 25.97 1.98 288 81 23.69 27.98 2.05
289 82 22.46 27.35 2.09 290 83 23.63 27.53 1.98 291 84 24.52 28.73
2.01 292 86 23.91 28.43 2.03 293 87 25.55 30.14 2.06 294 91 19.60
24.64 2.10 295 92 18.85 23.41 1.95 296 93 22.71 27.00 2.05 297 94
20.96 25.62 2.11 298 95 21.26 25.47 2.01 299 96 22.79 26.65 2.07
300 97 21.47 23.71 2.07 301 98 22.63 27.27 2.00 302 99 21.57 26.07
2.04 303 100 23.96 28.64 2.10 304 101 23.81 27.59 2.03 305 102
25.27 29.18 2.05 306 103 25.32 29.38 2.05 307 104 24.80 29.77 2.01
308 105 26.12 30.07 2.04 309 106 23.92 28.95 2.10 310 107 23.68
28.59 2.19 311 108 25.74 29.94 2.14 312 109 24.23 28.64 2.19 313
110 26.40 30.80 2.13 314 111 25.50 30.83 2.22 315 112 28.30 32.93
2.17 316 113 27.51 32.12 2.24 317 114 28.49 32.98 2.16 318 115
27.92 32.27 2.21
[0167] Further ethylene-based copolymers according to the invention
were prepared in a manner similar to that described above.
Properties of the copolymers are set forth in Table 6, below.
TABLE-US-00007 TABLE 6 MFR MFR Copolymer Mw, C.sub.2, (2.16 kg,
(21.6 kg, Tm, .degree. C. Hf, J/g Tc, .degree. C. Hc, J/g Tm,
.degree. C. Hf, J/g No. g/mol Mw/Mn wt % 230.degree. C.)
230.degree. C.) (1.sup.st melt) (1.sup.st melt) (2.sup.nd cool)
(2.sup.nd cool) (2.sup.nd melt) (2.sup.nd melt) E1 82000 1.84 63.6
9.2 175 -1.3 26.8 -2.3 30.9 -3.2 41.5 E2 71000 1.85 70.5 13.0 238
45.5 35.9 13.8 43.7 28.3 38.4 E3 97000 1.95 59.0 15.0 280 -17.7
22.9 -17.5 29.6 -17.8 29.7 E4 80000 1.93 69.2 12.0 239 43.5 38.4
12.4 45.1 24.5 39.9 E5 89000 2.07 62.3 12.0 259 -6.0 25.7 -6.3 37.5
-6.8 32.7 E6 99000 2.00 74.2 15.0 111 47.9 45.3 17.7 51.8 35.6 45.7
E7 103000 2.07 57.3 8.0 184 -18.6 19.4 -18.8 21.9 -19.8 20.8 E8
110000 2.04 60.7 7.9 159 -13.4 24.1 -13.5 25.0 -14.3 24.4 E9 109000
1.91 53.4 4.9 155 -28.5 8.6 -39.2 11.6 -29.6 8.3 E10 98000 1.85
49.2 12.0 377 -33.8 2.4 -51.3 11.4 -36.0 2.9 E11 108000 1.98 47.2
12.0 288 59.3 1.7 -54.8 11.7 78.6 4.1 E12 82000 1.84 63.6 9.2 175
-1.3 26.8 -2.3 30.9 -3.2 41.5
Examples 319-328
[0168] Blends of the copolymers listed in Table 6 were formed and
evaluated using dynamic mechanical thermal analysis (DMTA). In the
DMTA procedure, samples having approximate dimensions of
23.times.6.42 mm were die-cut from compression molded plaques
(molded at 180.degree. C. for 15 min) having a thickness of about
0.7 mm. The samples were conditioned under ambient conditions for
24 hours before DMTA measurements were taken using a DMTA V
instrument in tension mode (0.05% strain, 1 Hz frequency, 2.degree.
C./min heating rate, temperature range of -100 to 150.degree. C.).
Composition and DMTA properties of the blends are reported in Table
7, below. Multiple DMTA Tg results indicate multiple melting
peaks.
TABLE-US-00008 TABLE 7 Example No. Composition, wt %
.DELTA.C.sub.2, wt % DMTA Tg, .degree. C. 319 80% E1 + 20% E2 6.9
-44 320 30% E4 + 70% E5 6.9 -46 321 30% E2 + 70% E5 8.2 -46 322 70%
E3 + 30% E2 11.5 -48 323 70% E5 + 30% E6 11.9 -46 324 20% E4 + 80%
E10 15.8 -52 325 50% E4 + 50% E12 22.0 -54, -42 326 50% E2 + 50%
E12 23.3 -54, -40 327 50% E6 + 50% E11 25.0 -54, -36 328 50% E6 +
50% E12 27.0 -56, -34
Examples 329-338
[0169] The polymer blends of examples 319-328 were then mixed with
Americas Core 150 (AC150) basestock according to the following
procedure. A 50 g Brabender mixer was heated to 150.degree. C., and
the run was started at 30 rpm with the temperature kept stable. One
of the polymer blends of Examples 319-328 was added to the mixer
followed by 0.2 wt % Irganox 1076 and 0.07 wt % Irgafos 168 while
maintaining the torque below 1500. The mixer speed was increased to
65 rpm for 1 minute, then reduced to 35 rpm. 50 phr of AC150
basestock was then added slowly using a syringe (to prevent pooling
in the molten polymer) and the compositions were mixed for 5
minutes to fully incorporate the AC150. The resulting compositions
were then tested using the DMTA procedure set forth above.
Composition and DMTA properties of the blends are reported in Table
8, below. Multiple DMTA Tg results indicate multiple melting
peaks.
TABLE-US-00009 TABLE 8 Example DMTA Tg, No. C.sub.2, wt %
Composition, wt % w.DELTA.C.sub.2, t % .degree. C. 329 65.0 80% E1
+ 20% E2 6.9 -56 330 64.2 30% E4 + 70% E5 6.9 -54 331 64.4 30% E2 +
70% E5 8.2 -56 332 63.2 70% E3 + 30% E2 11.5 -58 333 65.5 70% E5 +
30% E6 11.9 -56 334 56.6 20% E4 + 80% E10 15.8 -56 335 58.7 50% E4
+ 50% E12 22.0 -62, -46 336 59.4 50% E2 + 50% E12 23.3 -60, -44 337
63.8 50% E6 + 50% E11 25.0 -62, -42 338 62.7 50% E6 + 50% E12 27.0
-62, -40
[0170] Certain embodiments and features have been described using a
set of numerical upper limits and a set of numerical lower limits.
It should be appreciated that ranges from any lower limit to any
upper limit are contemplated unless otherwise indicated. Certain
lower limits, upper limits and ranges appear in one or more claims
below. All numerical values are "about" or "approximately" the
indicated value, and take into account experimental error and
variations that would be expected by a person having ordinary skill
in the art.
[0171] Various terms have been defined above. To the extent a term
used in a claim is not defined above, it should be given the
broadest definition persons in the pertinent art have given that
term as reflected in at least one printed publication or issued
patent. Furthermore, all patents, test procedures, and other
documents cited in this application are fully incorporated by
reference to the extent such disclosure is not inconsistent with
this application and for all jurisdictions in which such
incorporation is permitted.
[0172] While the foregoing is directed to embodiments of the
present invention, other and further embodiments of the invention
may be devised without departing from the basic scope thereof, and
the scope thereof is determined by the claims that follow.
* * * * *