U.S. patent application number 16/333068 was filed with the patent office on 2019-07-25 for lubricant composition.
This patent application is currently assigned to Dow Global Technologies LLC. The applicant listed for this patent is Dow Global Technologies LLC. Invention is credited to John B. Cuthbert, Brian A. Jazdzewski, Ashish Kotnis.
Application Number | 20190225907 16/333068 |
Document ID | / |
Family ID | 60002116 |
Filed Date | 2019-07-25 |
United States Patent
Application |
20190225907 |
Kind Code |
A1 |
Kotnis; Ashish ; et
al. |
July 25, 2019 |
LUBRICANT COMPOSITION
Abstract
A lubricant composition including (a) a first low viscosity
polyalkylene oxide based fluid such as a combination of propylene
oxide (PO) and butylene oxide (BO) based fluid with a first alcohol
as an initiator; wherein the first low viscosity PO/BO based fluid
has a number average molecular weight of less than about 5 600 Da;
and (b) a second high viscosity polyalkylene oxide based fluid such
as a combination of ethylene oxide (EO) and propylene oxide (PO)
based fluid with a second alcohol as an initiator; wherein the
second high viscosity EO/PO based fluid has a number average
molecular weight greater than about 600 Da; a process for
manufacturing the above lubricant; and a driveline fluid made from
the above lubricant composition.
Inventors: |
Kotnis; Ashish; (Troy,
MI) ; Cuthbert; John B.; (Midland, MI) ;
Jazdzewski; Brian A.; (Pearland, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Dow Global Technologies LLC |
Midland |
MI |
US |
|
|
Assignee: |
Dow Global Technologies LLC
Midland
MI
|
Family ID: |
60002116 |
Appl. No.: |
16/333068 |
Filed: |
September 22, 2017 |
PCT Filed: |
September 22, 2017 |
PCT NO: |
PCT/US2017/052858 |
371 Date: |
March 13, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62398791 |
Sep 23, 2016 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10M 2209/1055 20130101;
C10N 2020/04 20130101; C10N 2030/06 20130101; C10N 2030/02
20130101; C10N 2040/04 20130101; C10M 2209/1065 20130101; C10M
2209/1075 20130101; C10M 2209/1045 20130101; C10M 107/34 20130101;
C10M 2209/1033 20130101; C10M 2209/103 20130101; C10M 2209/1075
20130101; C10M 2209/1085 20130101; C10M 2209/1045 20130101; C10M
2209/1055 20130101; C10M 2209/1055 20130101; C10M 2209/1065
20130101; C10M 2209/1085 20130101; C10M 2209/1045 20130101; C10M
2209/1055 20130101; C10M 2209/1085 20130101 |
International
Class: |
C10M 107/34 20060101
C10M107/34 |
Claims
1. A lubricant composition comprising: (a) a first low viscosity
polyalkylene oxide based fluid with a first alcohol as an
initiator; wherein the first low viscosity polyalkylene oxide based
fluid is copolymer formed with a combination of propylene oxide and
butylene oxide and has a number average molecular weight of less
than about 600; and (b) a second high viscosity polyalkylene oxide
based fluid with a second alcohol as an initiator; wherein the
second high viscosity polyalkylene oxide based fluid is a copolymer
formed with 50/50 or 45/55 ethylene oxide/propylene oxide and has a
number average molecular weight of 1,590 to 3,930; and wherein the
first low viscosity polyalkylene oxide based fluid is different
from the second high viscosity polyalkylene oxide based fluid.
2.-4. (canceled)
5. The composition of claim 1, wherein the first low viscosity
propylene oxide/butylene oxide combination based fluid is an about
50/50 propylene oxide/butylene oxide based fluid.
6. The composition of claim 1, wherein the first alcohol initiator
for the first low viscosity polyalkylene oxide based fluid is
dodecanol.
7. (canceled)
8. The composition of claim 1, wherein the second alcohol initiator
for the second high viscosity polyalkylene oxide based fluid is
butanol.
9. The composition of claim 1, wherein the molecular weight of the
first low viscosity polyalkylene oxide based fluid is from about
300 to about 600.
10. (canceled)
11. The composition of claim 1, wherein the concentration of the
first low viscosity polyalkylene oxide based fluid is from about 40
weight percent to about 80 weight percent.
12. The composition of claim 1, wherein the concentration of the
second high viscosity polyalkylene oxide based fluid is from about
20 weight percent to about 60 weight percent.
13. The composition of claim 1, wherein the lubricant composition
has an 11 to 12 centistokes viscosity at 100.degree. C. has a
viscosity index of greater than about 215 to about 225; a dynamic
viscosity of lower than about 40,000 centipoise at a temperature of
-40.degree. C.; in the absence of a pour point depressant or a
viscosity index improver.
14. A process for manufacturing a lubricant composition comprising
admixing: (a) a first low viscosity polyalkylene oxide based fluid
with a first alcohol as an initiator, wherein the first low
viscosity polyalkylene oxide is copolymer formed with a combination
of propylene oxide and butylene oxide and has a number average
molecular weight of less than about 600; and (b) a second high
viscosity polyalkylene oxide based fluid with a second alcohol as
an initiator, wherein the second high viscosity polyalkylene oxide
is a copolymer formed with 50/50 or 45/55 ethylene oxide/propylene
oxide and has a number average molecular weight of 1,590 to 3,930;
wherein the first low viscosity polyalkylene oxide based fluid is
different from the second high viscosity polyalkylene oxide based
fluid.
15. The process of claim 14, wherein the lubricant composition
having an about 11 centistokes to about 12 centistokes viscosity at
100.degree. C. has a viscosity index of greater than about 215 to
about 225; a dynamic viscosity of lower than about 40,000
centipoise at a temperature of -40.degree. C.; in the absence of a
pour point depressant or a viscosity index improver.
16. A driveline fluid made from a lubricant composition comprising:
(a) a first low viscosity polyalkylene oxide based fluid with a
first alcohol as an initiator; wherein the first low viscosity
polyalkylene oxide based fluid has a number average molecular
weight of less than 600; and (b) a second high viscosity
polyalkylene oxide based fluid with a second alcohol as an
initiator; wherein the second high viscosity polyalkylene oxide
based fluid has a number average molecular weight greater than 600;
and wherein the first low viscosity polyalkylene oxide based fluid
is different from the second high viscosity polyalkylene oxide
based fluid.
17. The driveline fluid of claim 16, wherein the first low
viscosity polyalkylene oxide based fluid has a number average
molecular weight of less than 580; and wherein the second high
viscosity polyalkylene oxide based fluid has a number average
molecular weight greater than 1,500.
18. The driveline fluid of claim 16, wherein the first low
viscosity polyalkylene oxide based fluid is a combination of a
propylene oxide and a butylene oxide.
19. The driveline fluid of claim 16, wherein the second high
viscosity polyalkylene oxide based fluid is a combination of an
ethylene oxide and a propylene oxide.
20. The driveline fluid of claim 16, wherein the lubricant
composition has an 11 to 12 centistokes viscosity at 100.degree. C.
has a viscosity index of greater than 215 to 225; a dynamic
viscosity of lower than 40,000 centipoise at a temperature of
-40.degree. C.; in the absence of a pour point depressant or a
viscosity index improver.
Description
FIELD
[0001] The present invention is related to a lubricant composition;
and more specifically, to a polyalkylene oxide-based lubricant
composition that exhibits improved properties when used in
applications such as for gear lubricants.
BACKGROUND
[0002] Heretofore, mineral oil-based lubricants (Groups I, II and
III base oils) and polyalphaolefin (PAO)-based lubricants (Group IV
base oils) have been used as driveline fluids for applications such
as engine oil, axle oils, and transmission fluids for decades. For
some of the applications, the known fluids are characterized as
"fill for life" meaning that once the lubricant has been
incorporated into a vehicle no oil change is required over the
useful life of the vehicle. The 2025 CAFE (Corporate Average Fuel
Economy) regulations related to the requirement that automobiles
perform at 54.5 miles per gallon (mpg) are prompting original
manufacturers (OEMs) to look at different compositions of
lubricants as a possible option that can further enhance fuel
economy without compromising durability.
[0003] One approach to improve the fuel economy of an automobile is
to improve the lubricant fluid used as gear lubricants for axles,
transfer cases and the like of an automobile. For example, reducing
the kinematic viscosity of the lubricant from about 11-12
centistokes (cSt) to about 5-6 cSt will, in turn, reduce spinning
losses by about 50 percent (%) to about 60%; and will reduce power
losses by about 30% to about 40%, thereby achieving an improvement
in fuel economy of from about 1% to about 2%. The challenge with
the above approach is that reducing the viscosity of a lubricant
can result in thin films which will cause metal to metal contact
which will ultimately cause higher friction and wear that can
result in premature failures, for example, of a gear system.
[0004] In an attempt to solve the above problems, conventional
compounds known as "viscosity modifiers" have been added to
conventional mineral oil-based oils (Groups I, II and III base
oils) to try to impart to the oils a high viscosity index (V.I.)
(e.g., a V.I. of from about 170 to about 190) which, in turn, would
provide oils with a low dynamic viscosity at a low temperature that
would help to reduce spinning losses. However, there is a limit to
the use of V.I. improvers (viscosity modifiers) because such V.I.
improvers have a tendency to shear degrade over a period of time
that causes permanent viscosity loss of lubricants. Fluids
(lubricants) with a V.I. of up to 180 have been used in the
industry with the help of viscosity modifiers to achieve a low
viscosity (e.g., <70,000 centipoise (cP) at -40 degrees
Centigrade (.degree. C.) for an 11-12 cSt fluid at 100.degree. C.)
at low temperatures. The above known lubricants can also use
compounds known as "friction modifiers" such as glycerol oleates
for friction reduction of the lubricant to achieve energy
efficiency.
[0005] Another challenge with the use of Groups I to III base oils
is that such oils have a high pour point; and hence, an additive
known as a "pour point depressant" is required to be added to the
oils to achieve the desired viscosities at -40.degree. C. of such
oils such that pumping losses of the oils at a low temperature are
minimized. Pumping losses are the energy losses due to moving a
liquid through a device. Higher viscosity liquids require more
energy to move (pump) than lower viscosity liquids. At start-up
conditions a higher viscosity liquid will take more energy to move,
resulting in higher fuel consumption.
[0006] Heretofore, in an attempt to solve the above problem of
pumping losses and to maximize the decrease of pumping losses,
Group IV base oils such as polyalphaolefin base fluids have been
used in place of Groups I to III base oils because Group IV base
oils inherently have, for example: (1) a good low temperature
property, (2) a better V.I. compared to Group III base oils, and
(3) a lower traction coefficient compared to Group III oils. In
addition, Group IV base oils in combination with V.I. improvers and
friction modifiers provide a better alternative compared to Group
III base oils in achieving fuel economy. Fluids (lubricants) with a
V.I. of up to 190 have been used in the industry with the help of
V.I. improvers and friction modifiers to achieve energy
efficiency.
[0007] Group V base oils, such as polyalkylene oxide based oils
made from 50/50 ethylene oxide (EO)/propylene oxide (PO) with
butanol as the initiator, have inherently a higher V.I. compared to
Group III and Group IV base oils (e.g., from about 30% to about 40%
higher); and the Group V base oils also have a significantly lower
(e.g., from about 30% to about 50% lower) traction coefficients and
hence are ideally suited for applications where energy efficiency
is required. One of the challenges with the Group V base oils is
that these fluids have a 15-20% higher density compared to Group
III base oils and Group IV base oils. And, the higher density of
the Group V base oils increases the dynamic viscosity at low
temperatures (e.g., from about 20.degree. C. to about 60.degree.
C.). The churning losses are directly proportional to the dynamic
viscosity; and hence, when the performance of formulated alcohol
initiated 50/50 EO/PO fluids without the use of V.I. improvers is
compared with formulated Group III and Group IV base oil with V.I.
improvers, the churning losses at low temperatures (e.g., from
about 20.degree. C. to about 60.degree. C.) are similar. Therefore,
the only benefit obtainable with the use of a formulated alcohol
initiated 50/50 EO/PO fluid (e.g., UCON.TM. 50-HB fluid; a
trademark of The Dow Chemical Company) is from about a 30% to about
50% lower traction coefficient which can help in achieving energy
efficiency to only a limited extent.
[0008] "Churning" or "spin" losses are energy losses due to a
mechanical element (gear) spinning in a liquid (oil). The drag
forces are calculated using the following equation:
Force=C.sub.d*v.sup.2*.rho.*A.
In above equation, C.sub.d is the drag coefficient and is a
function of the Reynolds number, V is velocity of the spinning
element, p is the density of the liquid, and A is a characteristic
wetted cross sectional area.
[0009] Mixtures of polyalkylene oxides are known in general.
However, a specific mixture of butanol initiated EO/PO copolymers
and dodecanol initiated PO/butylene oxide (BO) copolymers has
heretofore not been disclosed. Some lubricant formulations are
known as "oils of lubricating viscosity" and such "oils of
lubricating viscosity" are frequently defined as "Groups I, II,
III, IV and V base oils". Of the Group V base oils, polyalkylene
oxides and esters are generally specified as Group V base oils.
And, the known polyalkylene oxides are further defined generally as
including diether, monol, diol, C1-C20 alcohol initiated, any and
all combination of EO/PO/BO and higher oxides in any ratio, and
polymer blends thereof. However, the prior art does not disclose
specific blends of butanol initiated EO/PO copolymers and dodecanol
initiated PO/BO copolymers at ratios required to maintain the
miscibility of such copolymer components. Not all blends of
polyalkylene glycols are miscible, such immiscible blends are
impractical for use as a lubricant base stock. Typically, a
required additive or combination of additives is added to the
lubricant formulation to make the formulation useful.
SUMMARY
[0010] The present invention, in one embodiment, is directed to a
lubricant composition including: (a) a first low viscosity
polyalkylene oxide based fluid with a first alcohol as an
initiator; wherein the first low viscosity polyalkylene oxide based
fluid has a number average molecular weight of less than about 600
Da; and (b) a second high viscosity polyalkylene oxide based fluid
with a second alcohol as an initiator; wherein the second high
viscosity polyalkylene oxide based fluid has a number average
molecular weight greater than about 600 Da; and wherein the first
low viscosity polyalkylene oxide based fluid is different from the
second high viscosity polyalkylene oxide based fluid.
[0011] The problems of known lubricant compositions of the prior
art are addressed by the present invention lubricant composition.
The present invention lubricant composition provides important and
beneficial properties including for example: (i) a low temperature
viscosity (e.g., -40.degree. C. dynamic viscosity of less than
40,000 cP for an 11-12 cSt fluid at 100.degree. C.), (ii) a high
viscosity index (e.g., a viscosity index of greater than (>215),
and (iii) a low traction coefficient inter alia.
[0012] In another embodiment, the process of manufacturing the
above lubricant composition is provided herein.
[0013] In still another embodiment, the present invention is
directed to the use of the above lubricant composition in a
driveline fluid.
DETAILED DESCRIPTION
[0014] As described in ASTM D2270, viscosity index, abbreviated
V.I. and used with reference to a lubricant composition in this
disclosure, is an arbitrary number used to characterize the
variation of the kinematic viscosity of a petroleum product with
temperature. For oils of similar kinematic viscosity, the higher
the V.I. the smaller the effect of temperature on its kinematic
viscosity. The V.I. number is a widely used and accepted measure of
the variation in kinematic viscosity due to changes in the
temperature of a petroleum product between 40.degree. C. and
100.degree. C. A higher V.I. indicates a smaller decrease in
kinematic viscosity with increasing temperature of the lubricant.
The V.I. is used in practice as a single number indicating
temperature dependence of kinematic viscosity. V.I. is sometimes
used to characterize base oils for purposes of establishing engine
testing requirements for engine oil performance categories.
[0015] Dynamic viscosity, with reference to a lubricant
composition, herein means a viscosity as measured by a Stabinger
viscometer in units of mPa s. See ASTM D 7042, "Standard Test
Method for Dynamic Viscosity and Density of Liquids by Stabinger
Viscometer (and the Calculation of Kinematic Viscosity)".
[0016] "Pour point" herein, with reference to a lubricant
composition and petroleum products, means the lowest temperature at
which movement of the test specimen is observed under prescribed
conditions of test. The units of this measurement are in .degree.
C. Pour point can be measures using the procedure described in ASTM
D 6892, "Standard Test Method for Pour Point of Petroleum Products
(Robotic Tilt Method)".
[0017] "Traction" is a force transmitted through a lubricant film
between to surfaces in relative motion. A "traction coefficient" is
the measured traction force/normal applied force.
[0018] As used herein, Group I, II, III, IV and/or V base oils are
those as defined by the American Petroleum Institute (Annex E-API
Base Oil Interchangeability Guidelines for Passenger Car Motor Oils
and Diesel Engine Oils, March 2015 Version).
[0019] In its broadest scope, the present invention includes a
lubricant composition including: (a) a first low viscosity
polyalkylene oxide based fluid with a first alcohol as an
initiator; wherein the first low viscosity polyalkylene oxide based
fluid has a number average molecular weight of less than about 600
Da; and (b) a second high viscosity polyalkylene oxide based fluid
with a second alcohol as an initiator; wherein the second high
viscosity polyalkylene oxide based fluid has an average molecular
weight greater than about 600 Da; and wherein the first low
viscosity polyalkylene oxide based fluid is different from the
second high viscosity polyalkylene oxide based fluid. The number
average molecular weights provided herein are as reported by
manufacturer.
[0020] The viscosity of the first low viscosity polyalkylene oxide
based fluid, in general, can be from about 2 cSt to about 8 cSt in
one embodiment, from about 2 cSt to about 6 cSt in another
embodiment, and from about 2 cSt to about 4 cSt in still another
embodiment. The kinematic viscosity is calculated according to ASTM
D 7042.
[0021] The first low viscosity polyalkylene oxide based fluid with
a first alcohol as an initiator, in general, has a number average
molecular weight of less than about 600 Da in one embodiment, less
than about 550 Da in another embodiment, and less than about 400 Da
in still another embodiment.
[0022] The polyalkylene oxide of the first low viscosity
polyalkylene oxide based fluid can include for example, a
polyethylene oxide, a polypropylene oxide, a polybutylene oxide,
polyalkylene oxide copolymers derived from EO/PO/BO and polymer
mixtures thereof. For example, in one embodiment the first low
viscosity polyalkylene oxide based fluid is a combination of a
propylene oxide and a butylene oxide. In another embodiment, for
example, the combination of a propylene oxide and a butylene oxide
to arrive at a first low viscosity polyalkylene oxide based fluid
can include a 50/50 propylene oxide/butylene oxide based fluid (wt.
% basis).
[0023] The first low viscosity polyalkylene oxide based fluid may
include a lower molecular weight capped oil soluble polyalkylene
oxides (e.g., a capped UCON.TM. OSP, an oil soluble polyalkylene
oxide having less than about 600 Da average molecular weight, where
UCON.TM. is a trademark of The Dow Chemical Company). As used
herein, capped indicates that the terminal hydroxyl groups of the
polyalkylene oxide(s) are substituted with a hydrocarbyl group of
C1 to C12 or a C8 alkyl phenyl group (i.e., a benzyl group).
Preferably, capped oil soluble polyalkylene oxides are substituted
with a C1 to C4 hydrocarbyl group.
[0024] Generally, the first low viscosity polyalkylene oxide based
fluid (the "low viscosity fluid") used as component (a) of the
lubricant composition, includes for example UCON.TM. OSP-12 (a C12
alcohol initiated 50/50 PO/BO UCON.TM. OSP fluid with 3 cSt
viscosity at 100.degree. C., commercially available from The Dow
Chemical Company), UCON.TM. OSP-18 (a C12 alcohol initiated 50/50
PO/BO UCON.TM. OSP fluid with 4 cSt viscosity at 100.degree. C. and
550 Da), and mixtures thereof. The first low viscosity polyalkylene
oxide based fluid may also be formed using a C4-C18 alcohol
initiator, where different ratios of PO/BO can be used.
[0025] In a preferred embodiment, the low viscosity fluid useful in
the lubricant composition of the present invention may include for
example, UCON.TM. OSP-12 (a C12 alcohol initiated 50/50 PO/BO
UCON.TM. OSP fluid with 3 cSt viscosity at 100.degree. C.).
[0026] The concentration of the low viscosity fluid used in the
lubricant composition of the present invention may range generally
from about 30 weight percent (wt %) to about 90 wt % in one
embodiment, from about 40 wt % to about 80 wt % in another
embodiment, and from about 50 wt % to about 70 wt % in still
another embodiment, based on the total weight of the components in
the lubricant composition. When the concentration of the low
viscosity fluid is greater than 80 wt % concentration, it is
difficult to achieve a target viscosity of 11-12 cSt at 100.degree.
C.; and even if it were possible to achieve the target viscosity,
the V.I. of the resulting fluid is lower.
[0027] The first alcohol initiator useful for the first low
viscosity polyalkylene oxide based fluid can include for example,
an alcohol selected from ethanol, methanol, propanol, butanol,
dodecanol, and mixtures thereof.
[0028] The viscosity of the second high viscosity polyalkylene
oxide based fluid, in general, can be from about 16 cSt at
100.degree. C. to about 250 cSt at 100.degree. C. in one
embodiment, from about 25 cSt at 100.degree. C. to about 164 cSt at
100.degree. C. in another embodiment, and from about 25 cSt at
100.degree. C. to about 70 cSt at 100.degree. C. in still another
embodiment.
[0029] The second high viscosity polyalkylene oxide based fluid
with a second alcohol as an initiator, in general, has a number
average molecular weight of greater than about 600 in one
embodiment, greater than about 2,000 in another embodiment, and
greater than about 2,660 in still another embodiment.
[0030] Generally, the second high viscosity polyalkylene oxide
based fluid (the "high viscosity fluid") used as component (b) of
the lubricant composition includes for example a 50/50 EO/PO
copolymer blend having a molecular weight in the range of from
about 1,590 Da (e.g., UCON.TM. 50-HB-660, commercially available
from The Dow Chemical Company) to about 3,930 Da (e.g., UCON.TM.
50-HB-5100, commercially available from The Dow Chemical Company);
and mixtures thereof. The second high viscosity polyalkylene oxide
based fluid also includes for example a 45/55 EO/PO copolymer blend
with molecular weight in the range of from about 1,590 Da to about
3,930 Da.
[0031] In a preferred embodiment, the high viscosity fluid useful
in the lubricant composition of the present invention may include
for example, UCON.TM. 50-HB-2000 (a 50/50 EO/PO copolymer
commercially available from The Dow Chemical Company) with butanol
as initiator and molecular weight of 2,660 Da; SYNALOX.TM. 55-150B
(a 45/55 EO/PO copolymer blend, commercially available from The Dow
Chemical Company) with butanol as the initiator and molecular
weight of 2,200 Da; and mixtures thereof.
[0032] The concentration of the high viscosity fluid used in the
lubricant composition of the present invention may range generally
from about 10 wt % to about 70 wt % in one embodiment, from about
20 wt % to about 60 wt % in another embodiment, and from about 30
wt % to about 50 wt % in still another embodiment, based on the
total weight of the components in the lubricant composition. When
the concentration of the high viscosity fluid is greater than 50 wt
% concentration, the resulting fluid will have a viscosity of
greater than about 11-12 cSt target viscosity at 100.degree. C.
[0033] The ratio of component (a) such as UCON.TM. OSP-12, UCON.TM.
OSP-18 to component (b) such as UCON.TM. 50-HB-2000, UCON.TM.
50-HB-3520, UCON.TM. 50-HB-5100 or SYNALOX.TM. 55-150B, can be
generally from about 90 to about 10 in one embodiment; from about
70 to about 30 in another embodiment; and from about 50 to about 50
in still another embodiment.
[0034] The second alcohol useful as an initiator for the second
high viscosity polyalkylene oxide based fluid can include for
example, an alcohol selected from ethanol, methanol, propanol,
butanol, dodecanol, alcohols up to a carbon chain length of 18
(C18), and mixtures thereof. The second alcohol can also be
alcohols with mixed chain lengths. The second initiator alcohol,
when used, is different than the first initiator alcohol.
[0035] The lubricant composition of the present invention may also
include any number of optional components such as for example one
or more of antioxidants; antiwear compounds; extreme pressure, rust
and corrosion inhibitors; sulfur scavengers; detergents;
dispersants; antifoaming additives; and mixtures thereof.
[0036] The concentration of the optional additives for the
lubricant composition of the present invention may range generally
from 0 wt % to about 20 wt % in one embodiment, from about 0.01 wt
% to about 10 wt % in another embodiment, and from about 0.1 wt %
to about 5 wt % in still another embodiment, based on the total
weight of the components in the lubricant composition.
[0037] The process and type of equipment used to prepare the
lubricant composition of the present invention includes blending or
mixing of the above components in conventional mixing equipment or
vessels known in the art. For example, the preparation of the
lubricant composition of the present invention is achieved by
blending, in known mixing equipment, (a) the low viscosity fluid,
and (b) the high viscosity fluid, and (c) optionally any other
desirable additive.
[0038] All the above compounds of the lubricant composition are
typically mixed and dispersed in a vessel at a temperature enabling
the preparation of an effective working lubricant fluid. For
example, the temperature during the mixing of the above components
may be generally from about 25.degree. C. to about 75.degree. C. in
one embodiment, and from about 25.degree. C. to about 55.degree. C.
in another embodiment. Components (a)-(c) of the present invention
are miscible at room temperature (about 25.degree. C.) and at low
temperatures. (e.g., down to about -5.degree. C.).
[0039] The preparation of the lubricant composition of the present
invention, and/or any of the steps thereof, may be a batch or a
continuous process. In a preferred embodiment, the mixing process
of the components for preparing the lubricant composition; and the
mixing equipment used in the process may be any vessel and
ancillary equipment well known to those skilled in the art.
[0040] In one embodiment, the present invention includes a
combination or blend of at least two components including, for
example: (a) a first low viscosity (e.g., less than about 4 cSt)
polyalkylene oxide based fluid made from a combination of at least
two different polyalkylene oxide fluids with a first alcohol such
as dodecanol as the initiator and a average molecular weight of
less than about 600 Da; and (b) a high viscosity (e.g., greater
than about 4 cSt) polyalkylene oxide based fluid made from a
combination of at least two different polyalkylene oxide fluids
with a second alcohol such as butanol as the initiator and a number
average molecular weight of greater than about 600 Da. This unique
combination or mixture of two different polyalkylene oxide based
fluids of the present invention, one having a low viscosity and the
other having a high viscosity, provides several benefits including
based fluids having a low density, a high V.I. index, a low
traction coefficient, and good low temperature properties. One of
the surprising results of the fluid mixture of the present
invention is that the low temperature property at -40.degree. C. of
the combination of a low and a high viscosity or molecular weight
polyalkylene oxide base fluids as previously defined is better than
the baseline or control polyalkylene oxide fluid.
[0041] In one preferred embodiment, for example, the present
invention includes a blend of at least two components including (a)
a first low viscosity 50/50 PO/BO based fluid with a first alcohol
such as dodecanol as the initiator and the fluid having a number
average molecular weight of less than about 580 Da; and (b) a
second high viscosity 50/50 EO/PO or 45/55 EO/PO based fluid with a
second alcohol such as butanol as the initiator and the fluid
having a number average molecular weight greater than about 2,660
Da. For example, SYNALOX.TM. 55-150B, which can be one embodiment
of the second high viscosity 50/50 EO/PO or 45/55 EO/PO based
fluid, has a molecular weight of about 2,200 Da.
[0042] By using a combination of the above described EO/PO and
PO/BO based fluids in a lubricant composition, beneficial
properties are imparted to the lubricant composition including for
example, the composition has: (1) a higher V.I. for the same
100.degree. C. viscosity base oil compared to a dodecanol initiated
50/50 PO/BO base fluid and butanol initiated 50/50 EO/PO base
fluid; (2) a lower traction coefficient compared to dodecanol
initiated 50/50 PO/BO base fluid and similar traction coefficients
compared to butanol initiated 50/50 EO/PO base fluid; (3) a higher
V.I. compared to dodecanol initiated 50/50 PO/BO base fluid and
butanol initiated 50/50 PO/BO base fluid; (4) a lower dynamic
viscosity at -40.degree. C. and 40.degree. C. compared to butanol
initiated 50/50 EO/PO base fluid and dodecanol initiated 50/50
PO/BO base fluid; and (5) a lower density compared to the 50/50
EO/PO base fluids.
[0043] One of the surprising results of the lubricant composition
of the present invention is that the properties of the composition
at sub-zero temperature, e.g., at a temperature of about
-40.degree. C., are better (e.g., less than about 40,000 cP at
-40.degree. C. for a 11-12 cSt fluid at 100.degree. C.) than the
baseline 50/50 EO/PO based fluid. For example, using the unique
combination of the above described two fluids in a lubricant
composition, provides the composition with a higher V.I. (e.g., up
to about 229 V.I.), a lower dynamic viscosity (e.g., from about 10%
to about 20% lower dynamic viscosity) over the operating
temperature range of from about 20.degree. C. to about 100.degree.
C., a lower traction coefficient for base fluids, and extremely
good low temperature properties, without the need to use pour point
depressants or V.I. improvers.
[0044] In one embodiment, the present invention is directed to a
lubricant composition with a target 11-12 cSt viscosity at
100.degree. C. including: (a) a low viscosity (e.g., a viscosity of
from about 2 cSt to about 4 cSt at 100.degree. C.) 50/50 PO/BO
based fluid with dodecanol as the initiator and molecular weight of
less than about 580 Da; and (b) a high viscosity (e.g., a viscosity
of greater than about 25 cSt at 100.degree. C.) 50/50 EO/PO based
fluid with butanol as the initiator and a molecular weight greater
than about 1,500 Da; wherein the lubricant composition has a
viscosity index of greater than about 215; a dynamic viscosity of
lower than about 40,000 cP at a temperature of -40.degree. C.; and
a lower traction coefficient for the base fluid in the absence of a
pour point depressant or a V.I. improver. Examples of the low
viscosity 50/50 PO/BO based fluid include the UCON.TM. OSPs and
their capped analogs, as both discussed herein, and examples of the
high viscosity 50/50 EO/PO based fluids include UCON.TM. 50-HB
fluids and their capped analogs, also as both discussed herein.
[0045] In one preferred embodiment, the lubricant composition of
the present invention relates to compositions of a polyalkylene
oxides based base oil wherein a PO/BO co-polymer with a dodecanol
initiator and with a molecular weight of less than or equal to
about 550 Da is mixed with a EO/PO co-polymer with a butanol
initiator and with a molecular weight of greater than about 2,000.
The mixing ratios can vary, for example, a 67/33 (UCON.TM.
OSP-18/UCON.TM. 50-HB-2000) ratio can be used to achieve a
lubricant composition's target viscosity of about 11-12 cSt at
100.degree. C. for applications such as gear oils. In another
example, an 87/13 (UCON.TM. OSP-128/UCON.TM. 50-HB-2000) ratio can
be used to achieve a lubricant composition's target viscosity of
about 6 cSt at 100.degree. C. to target applications such as gear
oils, ATF oils, or engine oils in transportation applications.
[0046] The lubricant composition prepared by the above process of
the present invention exhibits several unexpected and unique
properties. For example, the dynamic viscosity of the lubricant
composition of the present invention is such that the composition
can be easily handled and processed. The lubricant composition with
a 11-12 cSt kinematic viscosity at 100.degree. C. may have a
dynamic viscosity in the range of from about 45 millipascals second
(mPa-s) to about 60 mPa-s at 40.degree. C. in one embodiment, from
about 47 mPa-s to about 55 mPa-s at 40.degree. C. in another
embodiment, and from about 47 mPa-s to about 52 mPa-s at 40.degree.
C. in still another embodiment. Greater than 60 mPa-s at 40.degree.
C. does not provide any improvement in fuel economy.
[0047] Another property that the lubricant composition exhibits is
a high V.I. value. Generally, the V.I. property can be between 209
and 229 in one embodiment, between about 215 and 229 in another
embodiment, and between about 220 and 229 in still another
embodiment. Below a V.I. of 209 for the combination mixture, the
40.degree. C. dynamic viscosities are similar to compounds similar
to the UCON.TM. 50-HB series of copolymers and lower spinning
losses cannot be achieved.
[0048] In another embodiment, the V.I. of the composition may be
further increased by using a low viscosity base oil as defined
above which is a C12 alcohol initiated PO/BO polyalkylene oxide
diether or capped base oil. It is known that the use of capped base
oils as the lower molecular weight component can impact the
solubility of the overall composition. Since homogenous mixtures
are desirable, the solubility of the C12 alcohol initiated PO/BO
polyalkylene oxide diether component can be further improved in the
higher molecular weight base oil, if necessary. Examples of
modification of the higher molecular base oil include, but are not
limited to, using a longer initiator such as a C12 alcohol
initiator or by using a combination of longer initiator and capping
the EO/PO polymer. The capped 50/50 EO/PO polymer may further
enhance the V.I. Another way of improving the solubility of C12
alcohol initiated PO/BO diether is by changing the EO/PO ratio in
the higher molecular weight base oil, for example, from 50/50 to
40/60 or 30/70. There may be a limitation on how much the ratio can
be altered as adding more PO will increase the traction
coefficients and will also adversely affect the -40.degree. C.
viscosity.
[0049] The lubricant composition can also exhibit a low traction
coefficient. Generally, the traction coefficient (e.g., at
80.degree. C. and 500 millimeters per second (mm/s) speed with 150%
slide to roll ratio) can be between about 0.025 and about 0.04 in
one embodiment, between about 0.025 and about 0.035 in another
embodiment, and between about 0.025 and about 0.03 in still another
embodiment. The traction coefficients under the same conditions may
be between about 0.045 and about 0.05 for a Group III base oil; and
between about 0.035 and about 0.04 for a Group IV base oil. The
fluids of the present invention have a traction coefficient which
is from about 25% to about 30% lower than a Group IV base oil
(polyalpha olefin or PAO). Fluids having lower traction
coefficients are desired as these fluids may provide benefit in
terms of fuel economy. A fluid having a traction coefficient close
to 0.035 under these conditions may not provide a fuel economy
benefit over a Group IV base oil.
[0050] Yet another property that the lubricant composition of the
present invention exhibits is an excellent viscosity at a lower
temperature, such as -40.degree. C. Generally, the -40.degree. C.
dynamic viscosity property can be between about 20,000 cP and about
50,000 cP in one embodiment, between about 20,000 cP and about
40,000 cP in another embodiment, and between about 20,000 cP and
about 30,000 cP in still another embodiment without the use of pour
point depressants.
[0051] After the lubricant composition is prepared as described
above, the lubricant composition can be used in various driveline
fluids. For example, the lubricant composition can be used for
driveline fluids for applications such as engine oil, axle oils,
transmissions fluids, worm gear oils, industrial gear oils, and the
like.
[0052] For applications such as automatic and manual transmission
fluids, axle oils and industrial gear oils, the gears are submerged
in the lubricant to a certain depth (e.g., a depth of from about
25% to about 50%) for lubrication. For such applications, churning
or spinning losses can be significant especially at low
temperatures and during start up and such losses can have a
negative impact on fuel economy and energy efficiency of an
automobile. These churning losses are directly dependent on the
dynamic viscosity of the fluid at that temperature and hence
reducing the dynamic viscosity can reduce the churning losses.
OEM's are contemplating lowering viscosity grade oils for these
types of applications to minimize these spinning losses and improve
fuel economy. The challenge with going to lower viscosity grades is
thinner films and faster transition to boundary and mixed
lubrication regime which can cause higher wear and affect the
durability and life of the gears. One way to achieve lower
viscosity at lower temperatures is by using V.I. improvers but
there are limitations when using V.I. improvers due to the shear
stability requirement.
[0053] To address this problem similar viscosity grades of fluids
are targeted; and by taking the advantage of lower density and
higher V.I. of UCON.TM. OSPs (e.g., UCON.TM. OSP-12 and/or UCON.TM.
OSP-18) and the better traction coefficient of UCON.TM. 50-HB
fluids, unique combinations of fluids can be developed that provide
lower dynamic viscosity at low temperatures, significantly improved
cold temperature viscosity, and traction coefficients similar to
the UCON.TM. 50-HB fluids. UCON.TM. OSPs have a 7-8% lower density
compared to the UCON.TM. 50-HB fluids whereas for the same
viscosity grades, UCON.TM. 50-HB fluids have 30% higher VI compared
to UCON.TM. OSP's.
EXAMPLES
[0054] The following Examples and Comparative Examples further
illustrate the present invention in more detail but are not to be
construed to limit the scope thereof.
[0055] In the following Examples and Comparative Examples, various
terms and designations were used and are explained as follows:
[0056] "EO" stands for ethylene oxide.
[0057] "PO" stands for propylene oxide.
[0058] "BO" stands for butylene oxide.
[0059] "UCON.TM. OSP" stands for oil soluble polyalkylene
glycols.
[0060] Traction coefficients as reported herein are derived from
Stribeck curves formed from data measured on a PCS Mini-Traction
Machine using 3/4 inch ball on a disc both made of AISI 52100
steel. Both ball and disc had surface finishes of Ra (arithmetical
mean deviation) better than 0.01 micron. The measurements were done
at 80.degree. C. and 120.degree. C., a load of 50 Newton, a slide
to roll ratio (SRR) of 150% and from speeds of 2000 mm/s to 100
mm/s. The test measurements were conducted 12 times in succession
at each temperature. The traction coefficient at 500 mm/s+/-2 mms
of the 12.sup.th repeat was reported.
[0061] In the following Examples, the following base oils described
in Table I were used for preparing lubricant compositions and for
evaluating the performance of such compositions.
TABLE-US-00001 TABLE I List of Base Oils BASE OIL CHEMISTRY OF BASE
OIL SUPPLIER UCON .TM. 50- Butanol initiated 50/50 weight per
weight The Dow HB-260 (w/w) EO/PO random co-polymer typical
Chemical kinematic viscosity of 11.1 cSt at 100.degree. C. Company
UCON .TM. 50- Butanol initiated 50/50 w/w EO/PO The Dow HB-400
random co-polymer typical kinematic Chemical viscosity of 16.3 cSt
at 100.degree. C. Company UCON .TM. 50- Butanol initiated 50/50 w/w
EO/PO The Dow HB-2000 random co-polymer typical kinematic Chemical
viscosity of 70.2 cSt at 100.degree. C. Company UCON .TM. 50-
Butanol initiated 50/50 w/w EO/PO The Dow HB-5100 random co-polymer
typical kinematic Chemical viscosity of 164 cSt at 100.degree. C.
Company UCON .TM. Dodecanol initiated 50/50 w/w PO/BO The Dow
OSP-12 random co-polymer typical kinematic Chemical viscosity of 3
cSt at 100.degree. C. Company UCON .TM. Dodecanol initiated 50/50
w/w PO/BO The Dow OSP-18 random co-polymer typical kinematic
Chemical viscosity of 3.9 cSt at 100.degree. C. Company UCON .TM.
Dodecanol initiated 50/50 w/w PO/BO The Dow OSP-32 random
co-polymer typical kinematic Chemical viscosity of 6.5 cSt at
100.degree. C. Company UCON .TM. Dodecanol initiated 50/50 w/w
PO/BO The Dow OSP-68 random co-polymer typical kinematic Chemical
viscosity of 12 cSt at 100.degree. C. Company SYNALOX .TM. Butanol
initiated BO homo polymer with The Dow OA-25 typical kinematic
viscosity of 4.9 cSt at Chemical 100.degree. C. Company SYNALOX
.TM. Butanol initiated BO homo polymer with The Dow OA-60 typical
kinematic viscosity of 9 cSt at Chemical 100.degree. C. Company
SYNALOX .TM. Butanol initiated 45/55 w/w EO/PO The Dow 55-150B
random co-polymer typical kinematic Chemical viscosity of 40-45 cSt
at 100.degree. C. Company SYNALOX .TM. Diol initiated 60/40 w/w
EO/PO random The Dow 40-D300 co-polymer typical kinematic viscosity
Chemical of 78 cSt at 100.degree. C. Company
[0062] In the following Examples and Comparative Examples, standard
measurements, analytical equipment and methods were used to measure
the properties of the lubricants as follows:
[0063] Dynamic Viscosity, Kinematic Viscosity, and Viscosity
Index
[0064] A viscometer, Stabinger Viscometer.TM. SVM 3000, measures
the dynamic viscosity and density of oils and fuels according to
ASTM D7042. From the above measurements, the viscometer
automatically calculates the kinematic viscosity and delivers
measurement results which are equivalent to ASTM D445. The
Stabinger Viscometer.TM. SVM 3000 is a rotational viscometer with a
cylinder geometry which works according to the modified Couette
principle with a rapidly rotating outer tube and an inner measuring
bob which rotates more slowly. A 2.5 milliliter (mL) sample is
placed in the viscometer and the dynamic viscosity and density are
measured as a function of temperature of from about 20.degree. C.
to about 100.degree. C.
[0065] Cold Temperature Viscosity Measurement
[0066] Cold temperature viscosity measurements are obtained using a
Brookfield viscometer. The principle of operation of the viscometer
is to rotate a spindle (which is immersed in a test sample fluid)
through a calibrated spring. The viscous drag of the fluid against
the spindle is measured by spring deflection. Spring deflection is
measured with a rotary transducer which provides a torque signal.
Approximately 7 mL of sample are placed in a cup, containing a
number 31 spindle, and placed in a small sample adapter that
connects to a Brookfield programmable rheometer. (The software
accounts for the specific geometry of this setup). The temperature
of the sample is controlled by an external bath that cools the
sample to the desired temperature.
[0067] Viscosity measurements are made starting at 0.degree. C. and
continuing down to -30.degree. C. At each temperature, 3 rotational
speeds are selected (based on previous data) to measure the
viscosity (each rotational speed is applied for 5 minutes in order
to reach steady-state). The measurement that has a torque reading
closest to 50% (must be +/-2% for -30.degree. C.) is recorded. A
single sample is used to record all desired temperatures (usually
0.degree. C., -10.degree. C., -20.degree. C., -30.degree. C., and
-40.degree. C.).
Examples 1-2 and Comparative Examples A-I
[0068] Table II describes the composition or formulation of various
base fluids. Table III describes the results of evaluating the
various formulations with the components listed in Table II. Table
III highlights the kinematic and dynamic viscosities, viscosity
index, low temperature dynamic viscosity, solubility, and traction
coefficients of different combinations of base fluids making up the
formulations. All of the fluids have a target viscosity of 11.7 cSt
at 100.degree. C.
TABLE-US-00002 TABLE II Various Base Fluids C. Ex A Ex. 1 Ex. 2 C.
Ex. B C. Ex. C C. Ex. D C. Ex. E C. Ex. F C. Ex. G C. Ex. H C. Ex.
I Components Wt % Wt % Wt % Wt % Wt % Wt % Wt % Wt % Wt % Wt % Wt %
UCON .TM. 50- 80.5000 HB-260 UCON .TM. 50- 19.5000 26.9000 HB-400
UCON .TM. 50- 33.1000 23.3000 10.0000 31.7000 22.4000 14.4000
29.5000 HB-2000 UCON .TM. 50- 23.2000 HB-5100 UCON .TM. OSP-
66.9000 76.8000 18 UCON .TM. OSP- 76.7000 32 UCON .TM. OSP- 73.1000
100.0000 68 Synalox OA60 90.0000 Capped 68.3000 UCON .TM. OSP- 18
(97060) Capped 77.6 UCON .TM. OSP- 32 (97061) Capped 85.6 UCON .TM.
OSP- 46 (97062) SYNALOX .TM. 70.5 OA-25 Total 100.00 100.00 100.00
100.00 100.00 100.00 100.00 100.00 100.00 100.00
TABLE-US-00003 TABLE III Test Results of Various Base Fluids Test
Results C. Ex. C. Ex. C. Ex. Test C. Ex. A Ex. 1 Ex. 2 C. Ex. B C.
Ex. C C. Ex. D C. Ex. E F* G* H* C. Ex. I Kinematic Viscosity 12
11.7 11.7 11.7 12.03 11.7 11.3 NM NM NM 11.71 at 100.degree. C.
Dynamic Viscosity 11.68 10.5 10.4 10.6 11.06 10.7 10.2 NM NM NM
10.75 at 100.degree. C. Dynamic Viscosity 57.5 51.4 50.2 55.7 62.2
68.7 61.5 NM NM NM 57.3 at 40.degree. C. Viscosity Index (V.I.) 221
217 221 199 186 155 168 NM NM NM 196 -(minus) 40.degree. C. 52800
31199 20994 49825 101000 94000 NM NM NM 75282 Dynamic Viscosity
(cP) Solubility Soluble Soluble Soluble Slightly Soluble Soluble
N/A Turbid Turbid Turbid Soluble turbid Traction coefficient at
0.027 0.028 0.03 Not -- -- 0.043 -- -- -- -- 80.degree. C. and 500
mm/s evaluated due to insolubility Traction coefficient at 0.021
0.021 0.022 Not -- -- 0.037 -- -- -- -- 120.degree. C. and 500 mm/s
evaluated due to insolubility *These examples were not measured due
to insolubility. NM = "not measured".
[0069] As described in Table III above, Comparative Example A (C.
Ex. A) shows the viscometrics and traction coefficients of standard
UCON.TM. 50-HB-260 with UCON.TM. 50-HB-400 and compares these
properties to an UCON.TM. OSP-68 base fluid highlighted in
Comparative Example E (C. Ex. E). These comparisons are made for
similar viscosity grades (75W85) which is dictated, in part, by
kinematic viscosity at 100.degree. C. UCON.TM. OSPs, in general,
have about 15% to about 20% higher dynamic viscosity at 40.degree.
C. compared to a UCON.TM. 50-HB fluid when the kinematic
viscosities are matched at 100.degree. C. UCON.TM. OSPs also have
about 75% to about 80% higher dynamic viscosity at -40.degree. C.
and about 60% higher traction coefficients when compared to
UCON.TM. 50-HB fluids.
[0070] A mixture of a similar viscosity UCON.TM. OSP and UCON.TM.
50-HB fluids was tested and the results of which are highlighted in
Comparative Example C (C. Ex. C). The mixture improved the V.I. of
the combination fluid when compared to UCON.TM. OSP alone but
didn't have any impact on dynamic viscosity at 40.degree. C. and
-40.degree. C. When lower viscosity UCON.TM. OSP (UCON.TM. OSP-18)
and higher viscosity UCON.TM. 50-HB fluids are combined, the
resulting fluid provides some unique low temperature viscometrics
as well as the traction coefficients of UCON.TM. 50-HB base fluids
are retained. Example 1 (Ex. 1) and Example 2 (Ex. 2) of the
present invention highlight the properties of these unique
combinations of fluids. At approximately 67/33 weight % of UCON.TM.
OSP-18 and UCON.TM. 50-HB-2000 which is required to achieve a
kinematic viscosity of 11.7 cSt at 100.degree. C., the resulting
fluid has a VI of 217 which is similar to that of the UCON.TM.
50-HB-260+UCON.TM. 50-HB-400 (221) fluid. Also this combination
provides 11% lower dynamic viscosity at 40.degree. C. and 40% lower
dynamic viscosity at -40.degree. C. These properties are further
enhanced when UCON.TM. OSP-18 is mixed with even a higher molecular
weight UCON.TM. 50-HB-5100 as highlighted in Ex. 2.
[0071] Surprisingly, it has been found that higher molecular weight
UCON.TM. OSPs (e.g., UCON.TM. OSP-32 and above) are not soluble in
the higher molecular weight UCON.TM. 50-HB-2000 fluids as
highlighted in Comparative Example B (C. Ex. B). Thus, dodecanol
initiated PO/BO copolymers with molecular weight less than 550 Da
and butanol initiated EO/PO copolymers with molecular weight
greater than 2,660 Da is a unique combination found to provide
benefits in terms of improved low temperature viscometrics and
lower traction coefficients. When combining capped UCON.TM. OSPs
with UCON.TM. 50-HB-2000 fluids, the resulting mixtures are not
soluble at room temperatures. This is highlighted in Comparative
Example G [C. Ex. G] to Comparative Example I (C. Ex. I).
[0072] A combination of lower molecular weight butanol initiated BO
homopolymer (SYNALOX.TM. OA-25) and higher molecular weight butanol
initiated EO/PO copolymer (UCON.TM. 50-HB-2000) were used as shown
in C. Ex. I. This combination was found to be miscible but the
composition of C. Ex. I did not provide as good of a low
temperature viscometrics compared to the Examples of the present
invention.
Examples 3-4 and Comparative Examples J-L
[0073] Table IV describes the composition of various base fluids.
Table V describes the results of evaluating the several
formulations with the components listed in Table IV. Table IV
highlights the kinematic and dynamic viscosities, viscosity index,
low temperature dynamic viscosity, solubility and traction
coefficients of different combinations of base fluids. All of the
fluids have a target viscosity of 11.7 cSt at 100.degree. C.
TABLE-US-00004 TABLE IV Various Base Fluids C. Ex A Ex. 1 Ex. 3 C.
Ex. J C. Ex. K Ex. 4 C. Ex. L Components Wt % Wt % Wt % Wt % Wt %
Wt % Wt % UCON .TM. 50-HB-260 80.5000 UCON .TM. 50-HB-400 19.5000
UCON .TM. 50-HB-660 56.5000 UCON .TM. 50-HB-2000 33.1000 39.0000
SYNALOX .TM. 55-150B 40.0000 48.0000 SYNALOX .TM. 40D300 33.0000
UCON .TM. OSP-12 61.0000 52.0000 UCON .TM. OSP-18 66.9000 43.5000
60.0000 67.0000 Total 100.00 100.00 100.00 100.00 100.00 100.00
100.00
TABLE-US-00005 TABLE IV Test Results of Various Base Fluids Test
Results Test C. Ex. A Ex. 1 Ex. 3 C. Ex. J C. Ex. K Ex. 4 C. Ex. L
Kinematic Viscosity 12 11.7 11.6 12 11.04 11.1 at 100.degree. C.
Dynamic Viscosity 11.68 10.5 10.3 11 10 10 at 100.degree. C.
Dynamic Viscosity 57.5 51.4 48 56 49.9 47 at 40.degree. C.
Viscosity Index (V.I.) 221 217 229 211 209 225 minus 40.degree. C.
Dynamic 52,800 31,199 Viscosity (cP) Solubility Soluble Soluble
Soluble Soluble Soluble Soluble Not soluble
[0074] The impact of even lower molecular weight UCON.TM. OSP such
as the UCON.TM. OSP-12 and a combination of UCON.TM. 50-HB-2000
were evaluated. The properties of this combination are show in
Example 3 (Ex. 3) in Table V. This combination further improves the
V.I. from 217 to 229 and reduces the low temperatures viscosities
even further compared to Ex. 1. In order to evaluate the impact of
using lower molecular weight 50/50 EO/PO copolymer, a blend of
UCON.TM. OSP-18 and UCON.TM. 50-HB-660 (Molecular weight of 1,590
and 26 cSt viscosity at 100.degree. C.) were produced labeled as
Comparative Example J (C. Ex. J) in Tables IV and V. This blend
renders a V.I. of 209 and its 40.degree. C. dynamic viscosity is
slightly lower compared to C. Ex. A. Therefore, no significant
benefits were achieved in terms of the V.I. and in terms of the low
temperature viscosities.
[0075] To evaluate the impact of change in EO/PO ratios and choice
of initiator, production of a blend of UCON.TM. OSP-18 and
SYNALOX.TM. 40-D300 was attempted as described in Comparative
Example L (C. Ex. L). This blend was insoluble with UCON.TM. OSP
suggesting that the EO/PO ratio cannot be increased beyond 50/50
unless changes are made in the initiators. In order to assess the
impact of molecular weights between 1,500 Da and 2,600 Da for the
EO/PO structures, a blend of SYNALOX.TM. 55-150B was made with
UCON.TM. OSP-18 (Comparative Example K) and UCON.TM. OSP-12
(Example 4). It was found that similar to the UCON.TM. OSP-18 and
UCON.TM. 50-HB-660 blends (C. Ex. J) a blend of SYNALOX.TM. 55-150B
and UCON.TM. OSP-18 had a V.I. of 209 and had no significant
advantage in terms of reducing the dynamic viscosity at 40.degree.
C. However, a blend of SYNALOX.TM. 55-150B and UCON.TM. OSP-12
(Example 4) did provide a significantly higher V.I. of 225 and also
a dynamic viscosity at 40.degree. C. which was significantly lower
compared to the baseline.
[0076] Overall, a combination of multiple blends of base oils
including those that include UCON.TM. OSP-12 and/or UCON.TM. OSP-18
with UCON.TM. 50-HB-2000, UCON.TM. 50-HB-5100 and/or SYNALOX.TM.
55-150B provided V.I. of above 217, 40.degree. C. dynamic
viscosities that were 10-15% lower than individual UCON.TM. 50-HB
fluids, similar traction coefficients as 50/50 EO/PO fluids and
10-50% lower dynamic viscosity compared to a baseline 50/50 EO/PO
copolymer of similar kinematic viscosity at 100.degree. C.
* * * * *