U.S. patent application number 12/504727 was filed with the patent office on 2011-01-20 for lubricant compositions containing stable boric acid suspension.
Invention is credited to William E. Olliges.
Application Number | 20110015104 12/504727 |
Document ID | / |
Family ID | 43450228 |
Filed Date | 2011-01-20 |
United States Patent
Application |
20110015104 |
Kind Code |
A1 |
Olliges; William E. |
January 20, 2011 |
Lubricant Compositions Containing Stable Boric Acid Suspension
Abstract
A lubricant composition including a lubricant comprising at
least one of a hydrocarbon oil or grease, a surfactant, an ester of
adipic acid, and a suspension of boric acid.
Inventors: |
Olliges; William E.; (Palm
City, FL) |
Correspondence
Address: |
CAHN & SAMUELS LLP
1100 17th STREET NW, SUITE 401
WASHINGTON
DC
20036
US
|
Family ID: |
43450228 |
Appl. No.: |
12/504727 |
Filed: |
July 17, 2009 |
Current U.S.
Class: |
508/160 |
Current CPC
Class: |
C10N 2050/10 20130101;
C10M 2207/282 20130101; C10M 2203/1006 20130101; C10M 2209/104
20130101; C10N 2020/06 20130101; C10M 2201/087 20130101; C10M
169/04 20130101; C10M 2209/104 20130101; C10M 2209/108
20130101 |
Class at
Publication: |
508/160 |
International
Class: |
C10M 125/26 20060101
C10M125/26 |
Claims
1. A lubricant composition, comprising: a lubricant comprising at
least one of a hydrocarbon oil or grease; about 0.001 wt.% to about
0.5 wt .% of a surfactant comprising octylphenol ethoxylate or
polyalkylene plycol ether; an ester of adipic acid
chemically-linked to the at least one lubricant; and a suspension
of particulate boric acid, wherein the boric acid has a particle
size of 0.5 to 2.5 microns.
2. A lubricant composition according to claim 1, wherein the ester
of adipic acid comprises diisodecyl adipate.
3. A lubricant composition according to claim 1, wherein the
lubricant comprises at least one of a synthetic oil, a mineral oil,
a silicon oil, a cutting oil, a transmission fluid, a hydraulic
fluid, or a grease.
4. (canceled)
5. A lubricant composition according to claim 1, wherein the boric
acid has a particle size of 0.5 to about 1 micron.
6. (canceled)
7. A lubricant composition according to claim 1, comprising 5 wt.%
to about 25 wt.% boric acid based on the weight of the lubricant
composition.
8-10. (canceled)
11. A lubricant composition, comprising: a lubricant comprising at
least one of a hydrocarbon oil or grease; about 0.001 wt.% to about
0.5 wt.% of a surfactant comprising polyalkylene glycol ether; and
a boric acid suspension comprising particulate boric acid and
diisodecyl adipate chemically linked to the lubricant, wherein the
boric acid has a particle size of 0.5 to 2.5 microns.
12. (canceled)
13. A method of making a lubricant composition comprising a stable
boric acid suspension, said method comprising: mixing an ester of
adipic acid, a surfactant comprising octylphenol ethoxylate or
polyalkylene glycol ether, and boric acid having a particle size of
0.5 to 2.5 microns to form a mixture by high shear blending,
wherein a temperature of the mixture does not exceed 120.degree.
F.; adding a lubricant comprising at least one of a hydrocarbon oil
or grease to the mixture; chemically linking the ester of adipic
acid to the at least one lubricant and forming a suspension of
boric acid in the at least one lubricant.
14. A method according to claim 13, further comprising dissolving
an ester of adipic acid comprising diisodecyl adipate in a
solvent.
15-16. (canceled)
17. A method according to claim 13, wherein a graft initiator and
catalyst are not used in making the lubricant composition.
18. A lubricant composition according to claim 1, wherein the ester
of adipic acid comprises a monomer or prepolymer that is chemically
linked to the at least one lubricant via polymer chains.
19. A lubricant composition according to claim 18, wherein polar
sites on the polymer chains form bridges between the particulate
boric acid and the at least one lubricant.
20. A lubricant composition according to claim 1, wherein the ester
of adipic acid is chemically-linked to the at least one lubricant
via hydrogen-carbon bonds.
21. A lubricant composition according to claim 1, wherein the
surfactant comprises octylphenol ethoxylate.
22. A lubricant composition according to claim 1, comprising about
200,000 ppm of boric acid.
23. A lubricant composition according to claim 1, wherein the
surfactant comprises polyalkylene glycol ether.
24. A lubricant composition according to claim 1, comprising: 30
wt.% to 60 wt.% of at least one lubricant comprising a hydrocarbon
oil or grease, based on the total weight of the lubricant
composition; 5 wt.% to 50 wt.% of diisodecyl adipate
chemically-linked to the at least one lubricant; and 5 wt.% to 25
wt.% of particulate boric acid, suspended in the at least one
lubricant.
25. A lubricant composition according to claim 1, comprising 20
wt.% to about 25 wt.% of particulate boric acid, suspended in the
at least one lubricant.
26. A lubricant composition according to claim 1, wherein the
lubricant comprises a silicon oil.
27. A lubricant composition according to claim 1, wherein the
lubricant comprises a hydraulic fluid.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates to a lubricant composition comprising
a boric acid suspension.
[0002] Lubricity is an essential element for lengthening the
usefulness of various motor and mechanical components which rely on
lubricants such as petroleum-based greases and oils, synthetic
oils, mineral oils, silicon oils, cutting oils, transmission
fluids, hydraulic fluids, and the like.
[0003] Boric acid is environmentally safe, inexpensive, and has an
unusual capacity to enhance the antifriction and antiwear
properties of sliding metal surfaces. Boric acid is a crystalline
compound, insoluble in hydrocarbons such as greases and oils.
[0004] There remains a great need for lubricants that provide high
lubricity and low wear. There is a further need for stable
suspensions that contain high concentrations of particulate boric
acid in the lubricants and that have long shelf-lives. The present
invention meets these needs and provides related advantages as
well.
SUMMARY OF THE INVENTION
[0005] According to an aspect of the present invention a lubricant
composition is provided comprising a lubricant comprising at least
one of a hydrocarbon oil or grease; a surfactant; an ester of
adipic acid linked to the lubricant; and a suspension of boric
acid.
[0006] According to another aspect of the invention, a lubricant
composition is provided comprising a lubricant comprising at least
one of a hydrocarbon oil or grease and a boric acid reaction
product comprising particulate boric acid and an ester of adipic
acid linked to the lubricant.
[0007] It is an object of the present invention to provide a
lubricant composition having superior lubricity thereby reducing
wear on treated mechanical parts.
[0008] It is another object of the present invention to provide a
lubricant composition having a high concentration of boric acid
remaining suspended in both a concentrate and a finished lubricant
composition.
[0009] It is an advantage of the present invention that the
lubricant composition provides a shelf-life of up to about five
years.
[0010] As used herein "substantially", "generally", "relatively",
and "about" are relative modifiers intended to indicate permissible
variation from the characteristic so modified. It is not intended
to be limited to the absolute value or characteristic which it
modifies but rather approaching or approximating such a physical or
functional characteristic.
DETAILED DESCRIPTION OF INVENTION
[0011] According to the present invention, a lubricant composition
comprises a boric acid suspension.
[0012] In this detailed description, references to "one
embodiment", "an embodiment", or "in embodiments" mean that the
feature being referred to is included in at least one embodiment of
the invention. Moreover, separate references to "one embodiment",
"an embodiment", or "in embodiments" do not necessarily refer to
the same embodiment; however, neither are such embodiments mutually
exclusive, unless so stated, and except as will be readily apparent
to those skilled in the art. Thus, the invention can include any
variety of combinations and/or integrations of the embodiments
described herein.
[0013] The lubricant composition comprises a lubricant comprising
at least one of a hydrocarbon-based oil or grease. Examples of such
an oil or grease include, but are not limited to, cutting oils,
synthetic oils, mineral oils, silicon oils, engine oils, hydraulic
fluids, mineral oils, vegetable oils, transmission fluids, e.g.,
oils for automatic transmissions, dry film lubricants, grease for
bearings and jet turbines, mixtures thereof, and other lubricants
that are non-reactive to boric acid. In specific embodiments, the
lubricant may comprise a light petroleum base oil. Examples
include, but are not limited to, ExxonMobil EHC-45 and Flint Hills
Resources.RTM. 100-HC or 100-SN. In specific embodiments, the
lubricant composition may comprise about 30 wt. % to about 60 wt. %
of lubricant, based on the total weight of the lubricant
composition.
[0014] According to the present invention, the lubricant
composition comprises a monomer or prepolymer. The monomer or
prepolymer may comprise adipic acid or a derivative thereof, such
as an ester of adipic acid (an adipate). In specific embodiments,
the monomer or prepolymer comprises diisodecyl adipate (DIDA),
commercially available as Hatcol 2910 or Jayflex.RTM. DIDA (e.g.,
CAS 27178-16-1).
[0015] The monomer or prepolymer chemically links onto the
lubricant via hydrogen-carbon bonds. Chemically linking polymer
chains to the lubricant is effective because the polymer chains may
double as surfactants. Polar sites on the polymer chains form
bridges between boric acid and the lubricant, thus stabilizing the
interaction between the two. In specific embodiments, the monomer
or prepolymer may be dissolved in a solvent before adding to the
lubricant.
[0016] According to the present invention, the lubricant
composition comprises a surfactant. Suitable surfactants include,
but are not limited to, dispersants such as Dow Triton.TM. X-100
(octylphenol ethoxylate), Uniquema Atlas.TM. G-5000 (polyalkylene
glycol ether), and Lubrizol Ircosperse.RTM. 2174. Sufficient
surfactant is used so that when particulate boric acid is added to
the lubricant, the macro globule particles of the boric acid are
broken up and prevented from reforming. In specific embodiments the
lubricant composition comprises from 0.001 to about 0.5 wt. %
(about 100 ppm to about 5000 ppm) surfactant, for example from
about 0.025 to about 0.045 wt. % (about 250 ppm to about 450 ppm)
surfactant, based on the weight of the lubricant composition.
[0017] According to the present invention, the lubricant
composition comprises particulate boric acid. In specific
embodiments, the boric acid is advantageously produced by the low
temperature jet-milling of commercially available boric acid. The
conditions of the low temperature jet-milling process can be
adjusted to produce boric acid particles having an average particle
size of 65 microns or less, as desired. In specific embodiments,
the boric acid has a particle size in the range of from about 0.1
to about 2.5 microns, for example in the range of from about 0.5 to
about 1 micron.
[0018] A boric acid reaction product is formed with a
chemically-linked lubricant. Without wishing to be bound by a
theory, it is believed that the boric acid's hydroxyl groups may
become loosely associated with lubricant. When the monomer or
prepolymer is chemically linked onto the lubricant, the resulting
polymer chains effectively stabilize the boric acid-lubricant
association and create a stable reaction product, effectively
suspending the boric acid particles in the lubricant.
[0019] According to the present invention, the lubricant
composition may be made by mixing boric acid, surfactant,
monomer/prepolymer, and lubricant to obtain a concentrate
containing the boric acid reaction product or suspension. In
specific embodiments, the components may be high shear blended, for
example, for about 15 minutes at about 5000 rpm, and at ambient
pressure, not to exceed 120.degree. F. In specific embodiments, a
graft initiator and/or catalyst is not used in the process of
making the concentrate or final lubricant composition.
[0020] In specific embodiments, the concentrate comprises about 5
to about 25 wt. % (about 50,000 ppm to about 250,000 ppm)
particulate boric acid, based on the total weight of the
concentrate, suspended in the lubricant.
[0021] In specific embodiments, the concentration of the ester of
adipic acid in the concentrate solution may vary within practically
any limits, for example, from between about 0.1 to about 50 wt. %
(about 1,000 ppm to 500,000 ppm), for example, between about 1 to
about 20 wt. % (about 10,000 ppm and about 200,000 ppm), based on
the weight of the concentrate.
[0022] The concentrate may be diluted with additional lubricant to
form a final lubricant composition comprising from about 0.001 to
about 20 wt. % (about 10 ppm to about 200,000 ppm) boric acid, for
example about 0.003 to about 0.5 wt. % (about 30 ppm to about 5,000
ppm) boric acid, based on the total weight of the finished
lubricant composition. The concentration of surfactant in the
finished lubricant composition may be from about 0.0002 to about
0.0006 wt. % (about 2 ppm to about 6 ppm). The concentration of
adipic acid ester in the finished lubricant composition may be from
about 5 wt. % to about 50 wt. % (about 50,000 to about 500,000
ppm).
[0023] Both the concentrate and the finished lubricant composition
remain stable, even when subjected to a variety of potentially
destabilizing conditions. For example, the boric acid remains
suspended at temperatures ranging from about to about -30.degree.
F. to 150.degree. F. and is shelf stable for up to about five
years. Moreover, the finished lubricant compositions provide
superior lubricity and reduced wear on mechanical components of the
internal combustion engine, while preventing corrosion.
[0024] The following are non-limiting examples of embodiments of
the present invention.
EXAMPLE 1
[0025] Five thousand, 5000, parts Dow Triton X-100 surfactant are
added to 500,000 parts Hatco 2910 diisodecyl adipate in a reaction
vessel and 200,000 parts boric acid are slowly added to the
reaction vessel and a homogeneous slurry is formed. 395,000 parts
lubricant ExxonMobil EHC-45 oil is slowly added to the slurry and
is stirred for thirty minutes in a high shear blender.
EXAMPLE 2
TABLE-US-00001 [0026] COMPONENT Wt. % (ppm) Diisodecyl 40 (400,000)
Adipate (DIDA) Boric Acid (1 um) 20 (200,000) High Shear, do not
exceed 120.degree. F. Dow Triton X-100 .5 (5,000) High Shear 15
minutes, do not exceed 120.degree. F. Add lubricant (10%/minute)
100-SN or EHC-45 39.5 (395,000) Lubricant High Shear 30 minutes, do
not exceed 120.degree. F. When complete, cool to Room Temperature
Store in Airtight Container
[0027] While various aspects of the present invention have been
particularly shown and described with reference to the exemplary,
non-limiting, embodiments above, it will be understood by those
skilled in the art that various additional aspects and embodiments
may be contemplated without departing from the spirit and scope of
the present invention.
[0028] Other aspects, objects and advantages of the present
invention can be obtained from a study of the drawings, the
disclosure and the appended claims.
* * * * *