U.S. patent application number 17/048012 was filed with the patent office on 2021-06-10 for lubricant composition for industrial engines with increased fe potential.
The applicant listed for this patent is TOTAL MARKETING SERVICES. Invention is credited to Stephane GAVAND, Bernard LAMY, Sophie OPPILLIART.
Application Number | 20210171854 17/048012 |
Document ID | / |
Family ID | 1000005443223 |
Filed Date | 2021-06-10 |
United States Patent
Application |
20210171854 |
Kind Code |
A1 |
GAVAND; Stephane ; et
al. |
June 10, 2021 |
LUBRICANT COMPOSITION FOR INDUSTRIAL ENGINES WITH INCREASED FE
POTENTIAL
Abstract
The present invention relates to the field of multipurpose
lubricants which may be used in the various components of
automotive vehicles, notably in the engine, the transmission or the
hydraulic circuit. The invention relates to the use of at least one
polymer which improves the viscosity index, chosen from
hydrogenated copolymers of diene and of aromatic vinyl, in a
lubricant composition for decreasing the viscosity of said
lubricant composition in the course of the use of said lubricant
composition during the lubrication of the various components of an
industrial vehicle, notably of a diesel engine industrial vehicle,
such as the engine, the gearbox and the hydraulic circuit, said
lubricant composition undergoing at least one thermal shear during
its use.
Inventors: |
GAVAND; Stephane; (DARDILLY,
FR) ; OPPILLIART; Sophie; (LYON, FR) ; LAMY;
Bernard; (TRIEL SUR SEINE, FR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TOTAL MARKETING SERVICES |
PUTEAUS |
|
FR |
|
|
Family ID: |
1000005443223 |
Appl. No.: |
17/048012 |
Filed: |
April 19, 2019 |
PCT Filed: |
April 19, 2019 |
PCT NO: |
PCT/EP2019/060237 |
371 Date: |
February 17, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10N 2030/02 20130101;
C10N 2040/04 20130101; C10N 2020/073 20200501; C10M 143/10
20130101; C10N 2040/08 20130101; C10M 2205/04 20130101; C10M
2205/06 20130101; C10M 143/12 20130101; C10N 2030/54 20200501; C10N
2020/065 20200501; C10N 2040/252 20200501; C10N 2020/019
20200501 |
International
Class: |
C10M 143/12 20060101
C10M143/12; C10M 143/10 20060101 C10M143/10 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 20, 2018 |
FR |
1853494 |
Claims
1-15. (canceled)
16. A method for preparing a lubricant composition for an
industrial vehicle, the method comprising: forming a lubricant
composition by adding a copolymer to a base oil, in an amount
sufficient to reduce the viscosity of the lubricant composition
when the lubricant composition is thermally sheared while
lubricating components of an industrial vehicle, wherein the
copolymer comprises hydrogenated diene monomers and hydrogenated
aromatic vinyl monomers.
17. The method of claim 16, wherein the diene monomer is chosen
from conjugated diene monomers comprising from 4 to 20 carbon
atoms.
18. The method of claim 16, wherein the aromatic vinyl monomer
comprises from 8 to 16 carbon atoms.
19. The method of claim 16, wherein the copolymer is a block
copolymer or a star copolymer.
20. The method of claim 16, wherein the copolymer is chosen from a
hydrogenated copolymer of isoprene and styrene (HCIS), a
hydrogenated copolymer of isoprene, butadiene and styrene, a
hydrogenated copolymer of butadiene and styrene (HCBS), and a
mixture thereof.
21. The method of claim 16, wherein the lubricant composition
comprises from 0.1% to 10% by weight of the copolymer, relative to
the total weight of the lubricant composition.
22. The method of claim 16, wherein the lubricant composition
further comprises one or more additives chosen from
friction-modifying additives, anti-wear additives, extreme-pressure
additives, detergent additives, antioxidant additives, viscosity
index (VI) enhancers other than the hydrogenated copolymers of
diene and of aromatic vinyl, pour-point depressant (PPD) additives,
dispersants, antifoams, thickeners, or mixtures thereof.
23. The method of claim 16, wherein the lubricant composition has a
kinematic viscosity at 100.degree. C. of between 9.3 and 16.3 cSt,
as measured by the ASTM D445 standard, after being thermally
sheared.
24. The method of claim 16, wherein the viscosity reduction is
sufficient to improve the fuel economy of the industrial
vehicle.
25. The method of claim 16, wherein the lubricant composition is
configured to undergo mechanical shearing while lubricating the
components of the industrial vehicle.
26. The method of claim 16, wherein the copolymer is a hydrogenated
copolymer of isoprene and styrene.
27. The method of claim 26, wherein the hydrogenated copolymer of
isoprene and styrene has formula (I) or (II) below: ##STR00003##
wherein, R1, R2, R3 and R4 are respectively hydrogenated
isoprene/styrene/isoprene copolymers, and l, m, n and o are,
independently integers greater than or equal to 0, such that the
number-average molar mass of the hydrogenated copolymer of isoprene
and styrene ranges from 10,000 to 700,000.
28. The method of claim 16, wherein the copolymer is a hydrogenated
copolymer of butadiene and styrene.
29. The method of claim 28, wherein the hydrogenated copolymer of
butadiene and styrene has formula (I') or (II') below: ##STR00004##
wherein, R.sup.1', R2', R3' and R4' are respectively hydrogenated
butadiene/styrene/butadiene copolymers, and l, m, n, and o are
independently integers greater than or equal to 0, such that the
number-average molar mass of the hydrogenated copolymer of
butadiene and styrene ranges from 10,000 to 700,000.
30. A method for lubricating components of an industrial vehicle,
the method comprising: lubricating the components of the industrial
vehicle with a lubricant composition during operation of the
industrial vehicle, such that the lubricant composition is
thermally sheared and the viscosity index of the lubricant
composition is reduced over time, wherein the lubricant composition
comprises a base oil and a copolymer comprising hydrogenated diene
monomers and hydrogenated aromatic vinyl monomers.
31. The method of claim 30, wherein the components of the
industrial vehicle comprise a diesel engine, a gearbox, and a
hydraulic circuit.
32. The method of claim 16, wherein the diene monomer is chosen
from a conjugated diene monomers comprising from 2 to 12 carbon
atoms.
33. The method of claim 16, wherein the lubricant composition
comprises from 0.1% to 2% by weight of the copolymer, relative to
the total weight of the lubricant composition.
34. The method of claim 16, wherein the lubricating comprises
lubricating an engine, a gearbox and a hydraulic circuit of the
industrial vehicle.
35. The method of claim 34, wherein the lubricating comprises
thermally and mechanically shearing the lubricant composition,
without supplying external oxygen to the lubricant composition.
Description
[0001] The present invention relates to the field of multipurpose
lubricants which may be used in the various components of
automotive vehicles, notably in the engine of a vehicle, the
transmission or the hydraulic circuit. More precisely, the
invention relates to the field of lubricants for industrial
machines, such as civil engineering machines, typically equipped
with industrial diesel engines. The present invention is directed
in particular toward proposing the use of specific polymers which
improve the viscosity index for the purpose of developing lubricant
compositions which show enhanced "FE (fuel economy) potential" over
time or CIFE (continuously increasing fuel economy), as explained
hereinbelow. This terminology covers lubricants whose FE potential
increases in the course of use, which is reflected not only by the
fact that the viscosity of the lubricant does not increase
significantly in the course of its use in the industrial diesel
engine, but also that it is less than the viscosity of the same
lubricants before their use.
[0002] Lubricant compositions, also referred to as "lubricants",
are commonly used in engines for the main purposes of reducing the
friction forces between the various metal parts in motion in the
engines, the transmission and the hydraulic circuit. They are also
efficient for preventing premature wear or even damage of these
parts, and in particular of their surface.
[0003] To do this, a lubricant composition is conventionally
composed of a base oil which is generally combined with several
additives intended for stimulating the lubricant performance of the
base oil, such as polymers which improve the viscosity index and
friction-modifying additives.
[0004] In the field of industrial engines, a single lubricant
composition is used directly in several types of application, in
particular in the various components of automotive vehicles such as
the engines, the transmission devices (gearboxes and transfer
boxes), the hydraulic circuits and other secondary components
without necessitating modification; in other words, the composition
of this fluid is directly suitable for the various types of use in
question.
[0005] Thus, a multipurpose lubricant composition must from the
outset meet particular viscosity constraints associated with the
fact that the functioning of the various components gives rise to
particular viscosities of said lubricant composition in the course
of its use. In other words, these constraints make it necessary to
target compromises in terms of viscosity and, as a corollary, in
the choice of the polymers, which has an impact on the viscosity
index.
[0006] Furthermore, industrial diesel engines are often subjected
to harsh or even drastic use.
[0007] Having available a single lubricant composition or
multipurpose composition for lubricating different components of a
vehicle, relative to the use of several multipurpose oils, offers
advantages notably in terms of ease of maintenance and storage, of
servicing of the vehicle or of a fleet of vehicles, of conditioning
and of logistics. This is particularly true for large fleets of
civil engineering vehicles, which are often used on isolated work
sites and subjected to inclement climatic conditions and which do
not have suitable storage devices.
[0008] Finally, added to the need to meet these intrinsic
constraints due to the architecture of industrial engines and to
the unique use for the various components which constitute them,
and also to a potentially prolonged use of these engines, is the
need to find lubricant compositions whose viscosity decreases in
the course of its use.
[0009] Lubricant compositions known as "fuel-eco" (FE) (meaning
fuel economy) lubricants are known, using polymers with a high
viscosity index (VI) and low shear, which have notably been
developed for the lubrication of industrial equipment used, for
example, in civil engineering or in mines and quarries. These
compositions afford a saving in fuel consumption.
[0010] Thus, when used, the lubricants of the prior art
conventionally undergo an increase in viscosity, which has a
negative impact on the FE nature of the lubricants.
[0011] In the case of these lubricants of FE nature, the viscosity
of the lubricant composition is reduced, thus enabling FE to be
achieved. However, this FE property is not enhanced over time.
Effectively, the viscosity of the fluid decreases due to the shear
of the polymer, but this is compensated for in service by the
appearance of soot and oxidation products, which increase the
overall viscosity of the lubricant.
[0012] GB1575449 discloses a copolymer of conjugated diene and of
aromatic vinyl which can be used as a viscosity index enhancer,
notably since it improves the oxidation stability of lubricant
compositions.
[0013] WO 2013/066915 discloses a lubricant oil composition
comprising a base oil of lubricant viscosity, a viscosity modifier
with a low shear stability index, and a viscosity modifier with a
high shear stability index.
[0014] These prior art documents are not directed toward improving
the FE potential over time, during the use of the lubricant
composition, notably under stress, such as the shear stresses that
are conventionally encountered during the use of a lubricant
composition in an industrial vehicle, notably a diesel engine
industrial vehicle.
[0015] In other words, there is a need for polymers which improve
the viscosity index, for the preparation of multipurpose lubricant
compositions whose viscosity decreases in the course of the use of
an industrial vehicle, notably of a diesel engine industrial
vehicle, and the viscosity of which is lower after use than that of
these same lubricant compositions before use, and in particular for
all three of the applications, namely the engine, the transmission
and the hydraulic circuit.
[0016] It follows therefrom that the decrease in viscosity that may
be observed in the course of the use of the lubricant compositions
which correspond to these properties increases over time.
[0017] Such lubricant compositions, the preparation of which is
targeted in the context of the present invention, may thus be
termed lubricant compositions with continuously increasing FE
(CIFE) properties.
[0018] In the context of the present invention, said FE properties
are also referred to as the FE potential or fuel economy
potential.
[0019] Thus, the invention is directed toward the use of at least
one polymer which improves the viscosity index, chosen from
hydrogenated copolymers of diene and of aromatic vinyl, in a
lubricant composition for improving the fuel economy potential of
the lubricant composition in the course of its use during the
lubrication of the various components of an industrial vehicle,
notably of a diesel engine industrial vehicle, such as the engine,
the gearbox and the hydraulic circuit.
[0020] The invention is directed, precisely, toward proposing the
use of at least one polymer which improves the viscosity index,
chosen from hydrogenated copolymers of diene and of aromatic vinyl,
for the purpose of preparing a lubricant composition intended for
lubricating the various components of an industrial vehicle,
notably of a diesel engine industrial vehicle, such as the engine,
the gearbox and the hydraulic circuit, characterized in that the
measured viscosity of said lubricant composition decreases in the
course of its use for lubricating said vehicle.
[0021] The invention is also directed toward proposing the use of
at least one polymer which improves the viscosity index, chosen
from hydrogenated copolymers of diene and of aromatic vinyl, in a
lubricant composition for decreasing the viscosity of said
lubricant composition in the course of the use of said lubricant
composition during the lubrication of the various components of an
industrial vehicle, notably of a diesel engine industrial vehicle,
such as the engine, the gearbox and the hydraulic circuit, said
lubricant composition undergoing at least one thermal shear during
its use.
[0022] The lubricant composition thus obtained may be used for
lubricating the various components of an industrial vehicle and in
particular the engine of an industrial vehicle, notably of a diesel
engine industrial vehicle, such as the machines used in civil
engineering or in mines and quarries. Said lubricant composition
thus has a viscosity profile suited to the conditions of use
required in each target component, namely the engine, the gearbox
and the hydraulic circuit. For the purposes of the present
invention, an industrial vehicle is to be distinguished from a
motor vehicle. Typically, the conditions of use impose long-term
mechanical stresses, such as mechanical shear and thermal shear. In
the context of the present invention, the term "thermal shear"
means thermal stresses or thermal shear stresses.
[0023] This thermal shear typically arises during exposure to at
least 70.degree. C., in particular at least 90.degree. C., more
particularly at least 100.degree. C., even more particularly from
170 to 300.degree. C., for example from 90 to 250.degree. C. or,
for example, from 100 to 200.degree. C.
[0024] The inventors have discovered that the polymer defined in
the present invention in a lubricant composition can reduce the
viscosity of said lubricant composition during its use, and can do
so even when the lubricant composition undergoes at least thermal
shear during its use, and more particularly thermal shear and
mechanical shear.
[0025] According to a particular embodiment of the invention, the
lubrication under the conditions of use comprising at least thermal
shear lasts at least 24 hours, for example at least 30 hours, or
even at least 40 hours, 80 hours or 120 hours.
[0026] According to another embodiment of the invention, the
polymer is used in order to reduce the viscosity of the lubricant
composition on conclusion of the dynamic road cycle, notably over a
period of at least 80 hours, in particular of at least 180 hours
and even more particularly of at least 250 hours, for instance that
described for step 2 of the engine test of example 3 of the
experimental section.
[0027] Contrary to all expectation, the inventors have discovered
that the lubricant composition obtained in accordance with the
invention has, on conclusion of prolonged use in an industrial
vehicle, a viscosity lower than that of a fresh lubricant
composition, this being the case under normal conditions of use.
Such normal conditions of use are, for example, understood as being
favorable to shear stresses, and more particularly without
supplying any external oxygen, i.e. other than the oxygen of the
ambient air. Typically, the use targeted in the present invention
is to be distinguished from a use for improving the oxidation
stability.
[0028] In other words, the present invention is directed toward
proposing the use of at least one polymer which improves the
viscosity index, chosen from hydrogenated copolymers of diene and
of aromatic vinyl, in a lubricant composition for decreasing the
viscosity of said lubricant composition in the course of the use of
said lubricant composition during the lubrication of the various
components of an industrial vehicle, notably of a diesel engine
industrial vehicle, such as the engine, the gearbox and the
hydraulic circuit, said lubricant composition undergoing at least
one thermal shear during its use, without supplying external
oxygen.
[0029] The examples hereinbelow thus demonstrate that the
composition in accordance with the invention, as obtained on
conclusion of the use, which is the subject of the present
invention, makes it possible to conserve the grade according to the
classification SAEJ300 after prolonged use in a diesel engine
industrial vehicle.
[0030] To model and prove this property, the inventors thus in
particular demonstrated that the compositions obtained with the use
of the copolymers for improving the viscosity in accordance with
the present invention [0031] (i) have a kinematic viscosity after
firing at 150.degree. C. for 504 hours lower than that of the
composition before firing, and [0032] (ii) have a kinematic
viscosity after the Bosch-90 cycles cycle lower than that of the
composition before this test, [0033] (iii) enable CIFE to be
achieved after an endurance test performed on an industrial engine,
notably a diesel industrial engine.
[0034] The inventors also demonstrated the decrease in the
viscosity of said lubricant composition in the course of these two
tests (i) and (ii) notably as illustrated in example 3.
[0035] The inventors also demonstrated that the decrease in the
viscosity of said lubricant composition in the course of test
(iii), notably as illustrated in example 4, enables CIFE to be
achieved.
[0036] Thus, as also emerges from the examples below and notably
from example 2, the hydrogenated copolymers of diene and of
aromatic vinyl are the only polymers improving the viscosity index
which have this property of gradually decreasing the viscosity of
said lubricant composition in the course of the use in a diesel
engine industrial vehicle and thus of producing lubricant
compositions that enable CIFE to be achieved.
[0037] The present invention also relates to the use of a
composition comprising at least one base oil and at least one
polymer which improves the viscosity index, chosen from
hydrogenated copolymers of diene and of aromatic vinyl, for
lubricating the various components of an industrial vehicle, and
notably of a diesel engine industrial vehicle, such as the engine,
the gearbox and the hydraulic circuit, in particular the engine of
an industrial vehicle, notably of a diesel engine industrial
vehicle, characterized in that the measured viscosity of said
lubricant composition decreases in the course of its use for
lubricating said vehicle.
[0038] According to one embodiment of the invention, the polymer is
used in order to reduce the viscosity of the lubricant composition
by at least 4%, preferably by at least 8%, more preferably by at
least 10%, preferentially by at least 12% after conditioning the
lubricant composition at 150.degree. C. for 504 hours.
[0039] According to one embodiment of the invention, the polymer is
used in order to reduce the viscosity of the lubricant composition
by at least 5%, preferably by at least 10%, more preferably by at
least 12%, preferentially by at least 15% on conclusion of the
dynamic road cycle, for instance that described for step 2 of the
engine test of example 3 of the experimental section.
[0040] The invention also relates to a process for lubricating the
various components of an industrial vehicle, and notably of a
diesel engine industrial vehicle, such as the engine, the gearbox
and the hydraulic circuit, in particular the engine of an
industrial vehicle, notably of a diesel engine industrial vehicle,
comprising the placing of said components in contact with a
lubricant composition comprising at least one base oil and at least
one polymer which improves the viscosity index, chosen from
hydrogenated copolymers of diene and of aromatic vinyl,
characterized in that the measured viscosity of said lubricant
composition decreases in the course of the lubrication of said
components, said lubricant composition undergoing at least one
thermal shear in the course of the lubrication, more particularly
undergoing at least one thermal shear and at least one mechanical
shear, in particular without supplying external oxygen.
[0041] As indicated above, according to another embodiment of the
invention, the lubrication in the course of the process comprising
at least the thermal shear lasts at least 24 hours, for example at
least 30 hours, or even at least 40 hours, 80 hours or 120
hours.
[0042] As indicated above, according to another embodiment of the
invention, the polymer makes it possible to reduce the viscosity of
the lubricant composition on conclusion of the dynamic road cycle,
notably over a period of at least 80 hours, in particular of at
least 180 hours and even more particularly of at least 250 hours,
for instance that described for step 2 of the engine test of
example 3 of the experimental section.
[0043] FIG. 1 illustrates the behavior of the viscosity of
compositions in accordance and not in accordance with the invention
at 100.degree. C. after Bosch 90 cycles tests (example 2).
[0044] FIGS. 2 and 3 illustrate the CIFE behavior of the
compositions in accordance with the invention during the endurance
test performed on an industrial diesel engine and relate to example
3 (viscosity measurement curves).
[0045] In the context of the invention, the lubricant compositions
under consideration are graded according to the SAEJ300
classification, defined by the formula (X)W(Y), in which X
represents 5, 10 or 15 and Y represents 30 or 40.
[0046] This SAEJ300 classification defines the viscosity grades of
new engine oils notably by measuring their kinematic viscosities at
100.degree. C.
[0047] The grade qualifies a selection of lubricant compositions
specifically intended for industrial vehicle use and which notably
meet quantified specificities with respect to various parameters
such as the multipurpose nature with respect to the various
components, the cold start viscosity, the cold pumpability, the
low-shear kinematic viscosity and the high-shear dynamic viscosity
at high temperature.
[0048] An engine oil is of grade 30 according to SAEJ300 if its
kinematic viscosity at 100.degree. C. is from 9.3 to 12.5 cSt.
[0049] An engine oil is of grade 40 according to SAEJ300 if its
kinematic viscosity at 100.degree. C. is from 12.5 to 16.3 cSt.
[0050] The ACEA standards define in detailed manner a certain
number of additional specifications for engine oils, and notably
impose the maintenance of a certain viscosity level for the oils in
service subjected to shear in the engine.
[0051] Thus, according to the sequence ACEA E7 or E9, the kinematic
viscosity of grade 30 and 40 engine oils, measured at 100.degree.
C., after the Bosch-90 cycles test, must be, respectively, greater
than 9.3 and 12.5 cSt.
[0052] These lubricant compositions in accordance with the present
invention have a kinematic viscosity at 100.degree. C. of greater
than 9.3 cSt, preferably in the range from 9.3 to 12.5 cSt after
the Bosch-90 cycles test according to the standard CEC-L-14-A-93
for a starting oil of grade 30.
[0053] These lubricant compositions in accordance with the present
invention have a kinematic viscosity at 100.degree. C. of greater
than 13.0 cSt, preferably in the range from 13.0 to 15.0 cSt after
the Bosch-90 cycles test according to the standard CEC-L-14-A-93
for a starting oil of grade 40.
[0054] Other characteristics, variants and advantages of the
lubricant compositions in accordance with the invention will emerge
more clearly on reading the description and the examples that
follow, which are given as nonlimiting illustrations of the
invention.
[0055] In the continuation of the text, the expressions "between .
. . and . . . ", "ranging from . . . to . . . " and "varying from .
. . to . . . " are equivalent and are intended to mean that the
limits are included, unless otherwise mentioned.
[0056] In the context of the present invention, the standard
CEC-L-14-A-93 (or ASTM D6278) defines the tests representative of
the shear conditions in the engine, known as the Bosch-90 cycles
test.
[0057] Without further mention in the continuation of the text, the
term "Bosch-90 cycles" refers to said standard.
[0058] To characterize the lubricant composition in accordance with
the present invention, the Applicant defined the representative
shear conditions of the engine.
[0059] Lubricant Composition in Accordance with the Invention
[0060] Polymer for Improving the Viscosity Index Chosen from
Hydrogenated Copolymers of Diene and of Aromatic Vinyl
[0061] In the context of the present invention, the diene may be a
conjugated diene comprising from 4 to 20 carbon atoms, preferably
from 2 to 12 carbon atoms.
[0062] In particular, the diene may be a conjugated diene
comprising from 2 to 20 carbon atoms, preferably from 4 to 12
carbon atoms.
[0063] Preferably, the diene may be chosen from butadiene,
isoprene, piperylene, 4-methylpenta-1,3-diene,
2-phenyl-1,3-butadiene, 3,4-dimethyl-1,3-hexadiene and
4,5-diethyl-1,3-octadiene.
[0064] Advantageously, the diene may be an isoprene or a
butadiene.
[0065] In the context of the present invention, the aromatic vinyl
may comprise from 8 to 16 carbon atoms.
[0066] Preferably, the aromatic vinyl may be chosen from styrene,
alkoxystyrene, vinylnaphthalene and alkylvinylnaphthalene.
Typically, the alkoxy and alkyl groups comprise from 1 to 6 carbon
atoms.
[0067] Advantageously, the aromatic vinyl is styrene.
[0068] Advantageously, the polymer in accordance with the invention
may be chosen from a hydrogenated copolymer of isoprene and styrene
(HCIS), a hydrogenated copolymer of isoprene, butadiene and
styrene, a hydrogenated copolymer of butadiene and styrene (HCBS),
and a mixture thereof.
[0069] According to a preferred embodiment, the polymer in
accordance with the invention may be chosen from a hydrogenated
copolymer of isoprene and styrene (HCIS), a hydrogenated copolymer
of butadiene and styrene (HCBS), and a mixture thereof.
[0070] According to this preferred embodiment, the copolymer used
in the present invention is not a copolymer of isoprene, butadiene
and styrene. Still according to this preferred embodiment, the
copolymer used in the present invention is not a terpolymer.
[0071] For example, the hydrogenated copolymers of isoprene and
styrene and the hydrogenated copolymers of isoprene, butadiene and
styrene for the purposes of the invention are described in patent
application EP 2 363 454 and the structures and definitions of
these polymers as described in EP 2 363 454 are incorporated into
the description of the present patent application.
[0072] In the context of the present invention, the hydrogenated
copolymer of diene and styrene may be a block copolymer or a star
copolymer.
[0073] In the context of the present invention, the polymers
according to the present invention may have a number-average
molecular mass from about 10 000 to 700 000, preferably from about
30 000 to 500 000. The term "number-average molecular mass" as used
herein denotes the number-average weight measured by gel permeation
chromatography (GPC) with a polymer standard, after
hydrogenation.
[0074] According to a preferred embodiment, the HCIS and HCBS
copolymers do not comprise any monomer additional to the monomers,
respectively, of hydrogenated isoprene and styrene and of
hydrogenated butadiene and styrene.
[0075] According to a particular embodiment, the polymer is a
hydrogenated copolymer of isoprene and styrene (HCIS).
[0076] For example, among the HCIS copolymers that are suitable for
use in the present invention, mention may be made of the copolymers
having the formula (I) or (II) below:
##STR00001##
[0077] with R1, R2, R3 and R4: (hydrogenated)
isoprene/styrene/isoprene copolymers, l, m, n and o are,
independently of each other, integers greater than or equal to 0
such that the number-average molar mass of the copolymer ranges
from 10 000 to 700 000.
[0078] These copolymers of formula (II) are star copolymers,
obtained by reaction of isoprene/styrene/isoprene block copolymers
with divinylbenzene followed by hydrogenation, according to
techniques known to those skilled in the art.
[0079] For the purposes of the invention, hydrogenated copolymers
of isoprene and styrene (HCIS) or hydrogenated copolymers of
isoprene, butadiene and styrene that may notably be mentioned
include those sold under the names linear SV154, star SV300 (pure
or diluted in the form SV301), star SV260 (pure or diluted in the
form SV 261) by the company Infineum and Lz 7306 by the company
Lubrizol.
[0080] According to a particular embodiment, the polymer is a
hydrogenated copolymer of butadiene and styrene (HCBS).
[0081] For example, among the HCBS copolymers that are suitable for
use in the present invention, mention may be made of the copolymers
having the formula (I') or (II') below:
##STR00002##
[0082] with R1', R2', R3' and R4': (hydrogenated)
butadiene/styrene/butadiene copolymers, l, m, n and o are,
independently of each other, integers greater than or equal to 0
such that the number-average molar mass of the copolymer ranges
from 10 000 to 700 000.
[0083] These copolymers of formula (II') are star copolymers,
obtained by reaction of butadiene/styrene/butadiene block
copolymers with divinylbenzene followed by hydrogenation.
[0084] As HCBS copolymers, mention may notably be made of those
sold under the name Lz 7408 (pure or diluted in the form Lz 7418A)
by the company Lubrizol or Hitec 6005 by the company Afton
Chemicals.
[0085] Thus, according to a particular embodiment of the invention,
the hydrogenated copolymer of isoprene and styrene (HCIS) and the
hydrogenated copolymer of butadiene and styrene (HCBS) are of star
type.
[0086] In particular, the content of polymer(s) for improving the
viscosity index in the lubricant composition according to the
invention is from 0.1% to 10% by weight, relative to the total
weight of the lubricant composition, preferably from 0.1% to 8%,
more preferentially from 0.1% to 5%, even more preferentially from
0.1% to 2%. This amount is understood as an amount of polymer
active material. Specifically, the polymer used in the context of
the present invention may be in the form of a dispersion in a
mineral or synthetic or pure oil.
[0087] In particular also, a composition used according to the
invention may comprise from 1% to 25% by weight, preferably from 2%
to 20% by weight, more preferentially from 4% to 20% by weight of
polymer(s) for improving the viscosity index diluted in a base oil,
relative to the total weight of the composition.
[0088] It falls to a person skilled in the art to adapt the content
of copolymer as defined above to be used in a lubricant
composition.
[0089] Thus, according to a particular embodiment, the present
invention also relates to the use of a composition comprising at
least one base oil and a polymer which improves the viscosity
index, chosen from a hydrogenated copolymer of isoprene and styrene
(HCIS) and a hydrogenated copolymer of butadiene and styrene
(HCBS), for lubricating the various components of an industrial
vehicle, and notably of a diesel engine industrial vehicle, such as
the engine, the gearbox and the hydraulic circuit, in particular
the engine of an industrial vehicle, notably of a diesel engine
industrial vehicle, characterized in that the measured viscosity of
said lubricant composition decreases in the course of its use for
lubricating said vehicle, said lubricant composition undergoing at
least one thermal shear during its use, more particularly
undergoing at least one thermal shear and at least one mechanical
shear, in particular without supplying any external oxygen.
[0090] The copolymers defined above may be mixed with one or base
oils, in particular as defined below, to form a ready-to-use
lubricant composition. Alternatively, they may be added alone or as
a mixture with one or more other additives, as defined below, as
additives intended to be added to a mixture of base oils for
improving the properties of the lubricant composition.
[0091] According to one embodiment of the invention, the use in
accordance with the present invention is characterized in that the
lubricant composition comprises a base oil from groups I to V, more
particularly II or III, and optionally an additive pack and
optionally a pour-point enhancer.
[0092] Base Oil
[0093] The base oils used in the lubricant formulation according to
the present invention are oils, of mineral, synthetic or natural
origin, used alone or as a mixture, belonging to groups I to V
according to the API classification (table A), or the equivalents
thereof according to the ATIEL classification, or mixtures thereof,
one of the characteristics of which is that they are insensitive to
shear, i.e. their viscosity is not modified under shear.
TABLE-US-00001 TABLE A Content of Sulfur Viscosity saturates
content index (VI) Group I <90% >0.03% 80 .ltoreq. VI <
120 Mineral oils Group II .gtoreq.90% .ltoreq.0.03% 80 .ltoreq. VI
< 120 Hydrocracked oils Group III .gtoreq.90% .ltoreq.0.03%
.gtoreq.120 Hydrocracked or hydroisomerized oils Group IV
Poly-.alpha.-olefins (PAO) Group V Esters and other bases not
included in groups I to IV
[0094] The mineral base oils include all types of bases obtained by
atmospheric and vacuum distillation of crude oil, followed by
refining operations such as solvent extraction, deasphalting,
solvent deparaffinning, hydrotreating, hydrocracking,
hydroisomerization and hydrofinishing.
[0095] The synthetic base oils may be esters of carboxylic acids
and of alcohols or poly-.alpha.-olefins or polyalkylene glycols.
The poly-.alpha.-olefins used as base oils are obtained, for
example, from monomers comprising 4 to 32 carbon atoms, for example
from decene, octene or dodecene, and with a viscosity at
100.degree. C. of between 1.5 and 15 mm.sup.2s.sup.-1 according to
the standard ASTM D445. Their average molecular mass is generally
between 250 and 3000 according to the standard ASTM D5296.
[0096] The polyalkylene glycols are obtained by polymerization or
copolymerization of alkylene oxides comprising from 2 to 8 carbon
atoms, in particular from 2 to 4 carbon atoms.
[0097] Mixtures of synthetic and mineral oils may also be used.
[0098] There is generally no limit as regards the use of different
lubricant bases to produce the lubricant compositions according to
the invention, other than the fact that they must have properties,
notably in terms of viscosity, viscosity index, sulfur content and
oxidation resistance, which are suitable for use for the various
components of an industrial vehicle, such as the engine, the
gearbox and the hydraulic circuit, in particular for industrial
vehicle engines. Needless to say, they must also not affect the
properties afforded by the oil(s) with which they are combined.
[0099] According to a particular embodiment, the lubricant
composition in accordance with the present invention, the use of
which is the subject of the present invention, uses a base oil from
group II.
[0100] They represent in the lubricant composition in accordance
with the invention at least 50% by weight, relative to the total
weight of the composition, in particular at least 60% by weight and
more particularly between 60% and 90% by weight.
[0101] Additives
[0102] The composition in accordance with the present invention may
also comprise additives or "an additive pack" according to the
terminology conventionally used in the field of multipurpose
lubricant compositions.
[0103] The additive packs used in the lubricant formulations in
accordance with the invention are conventional and also known to a
person skilled in the art and meet performance levels defined,
inter alia, by the ACEA (Association des Constructeurs Europeens
d'Automobiles) and/or the API (American Petroleum Institute).
[0104] A lubricant composition according to the invention may thus
comprise one or more additives chosen from friction-modifying
additives, antiwear additives, extreme-pressure additives,
detergent additives, antioxidant additives, viscosity index (VI)
enhancers other than the hydrogenated copolymers of diene and of
aromatic vinyl, pour-point depressant (PPD) additives, dispersants,
antifoams, thickeners, and mixtures thereof.
[0105] As regards the friction-modifying additives, they may be
chosen from compounds providing metal elements and ash-free
compounds.
[0106] Among the compounds providing metal elements, mention may be
made of complexes of transition metals such as Mo, Sb, Sn, Fe, Cu
or Zn, the ligands of which may be hydrocarbon-based compounds
comprising oxygen, nitrogen, sulfur or phosphorus atoms.
[0107] The ash-free friction-modifying additives are generally of
organic origin and may be chosen from fatty acid monoesters of
polyols, alkoxylated amines, alkoxylated fatty amines, fatty
epoxides, borate fatty epoxides, fatty amines or fatty acid esters
of glycerol. According to the invention, the fatty compounds
comprise at least one hydrocarbon-based group comprising 10 to 24
carbon atoms.
[0108] According to an advantageous variant, a lubricant
composition according to the invention comprises at least one
friction-modifying additive, in particular based on molybdenum.
[0109] In particular, the molybdenum-based compounds may be chosen
from molybdenum dithiocarbamates (Mo-DTC), molybdenum
dithiophosphates (Mo-DTP), and mixtures thereof.
[0110] According to a particular embodiment, a lubricant
composition according to the invention comprises at least one
Mo-DTC compound and at least one Mo-DTP compound. A lubricant
composition may notably comprise a molybdenum content of between
1000 and 2500 ppm.
[0111] Advantageously, such a composition makes it possible to make
additional fuel savings.
[0112] Advantageously, a lubricant composition according to the
invention may comprise from 0.01% to 5% by weight, preferably from
0.01% to 5% by weight, more particularly from 0.1% to 2% by weight
or even more particularly from 0.1% to 1.5% by weight, relative to
the total weight of the lubricant composition, of
friction-modifying additives, advantageously including at least one
molybdenum-based friction-modifying additive.
[0113] As regards the antiwear additives and the extreme-pressure
additives, they are more particularly directed toward protecting
the friction surfaces by forming a protective film adsorbed onto
these surfaces. A wide variety of antiwear additives exists.
[0114] Antiwear additives chosen from polysulfide additives,
sulfur-based olefin additives or phospho-sulfur-based additives,
such as metal alkylthiophosphates, in particular zinc
alkylthiophosphates and more specifically zinc
dialkyldithiophosphates or ZnDTP, are most particularly suitable
for use as lubricant compositions according to the invention. The
preferred compounds are of formula Zn((SP(S)(OR)(OR')).sub.2, in
which R and R', which may be identical or different, independently
represent an alkyl group preferentially including from 1 to 18
carbon atoms.
[0115] Advantageously, a lubricant composition according to the
invention may comprise from 0.01% to 6% by weight, preferentially
from 0.05% to 4% by weight and more preferentially from 0.1% to 2%
by weight, relative to the total weight of the composition, of
antiwear additives and of extreme-pressure additives.
[0116] As regards the antioxidant additives, they are essentially
dedicated toward retarding the degradation of the lubricant
composition in service. This degradation may notably be reflected
by the formation of deposits, the presence of sludges, or an
increase in the viscosity of the lubricant composition. They act
notably as free-radical inhibitors or hydroperoxide destroyers.
Among the commonly used antioxidant additives, mention may be made
of antioxidants of phenolic type, antioxidant additives of amine
type and phospho-sulfur-based antioxidant additives. Some of these
antioxidant additives, for example the phospho-sulfur-based
antioxidant additives, may be ash generators. The phenolic
antioxidants additives may be ash-free or may be in the form of
neutral or basic metal salts. The antioxidants additives may
notably be chosen from sterically hindered phenols, sterically
hindered phenol esters and sterically hindered phenols comprising a
thioether bridge, diphenylamines, diphenylamines substituted with
at least one C.sub.1-C.sub.12 alkyl group,
N,N'-dialkyl-aryl-diamines, and mixtures thereof.
[0117] Preferably, the sterically hindered phenols are chosen from
compounds comprising a phenol group, in which at least one carbon
vicinal to the carbon bearing the alcohol function is substituted
with at least one C.sub.1-C.sub.10 alkyl group, preferably a
C.sub.1-C.sub.6 alkyl group, preferably a C.sub.4 alkyl group,
preferably with a tert-butyl group.
[0118] Amine compounds are another class of antioxidant additives
that may be used, optionally in combination with the phenolic
antioxidants additives. Examples of amine compounds are aromatic
amines, for example the aromatic amines of formula
NR.sup.5R.sup.6R.sup.7 in which R.sup.5 represents an optionally
substituted aliphatic or aromatic group, R.sup.6 represents an
optionally substituted aromatic group, R.sup.7 represents a
hydrogen atom, an alkyl group, an aryl group or a group of formula
R.sup.8S(O).sub.zR.sup.9 in which R.sup.8 represents an alkylene
group or an alkenylene group, R.sup.9 represents an alkyl group, an
alkenyl group or an aryl group and z represents 0, 1 or 2.
[0119] Sulfurized alkylphenols or the alkali metal or
alkaline-earth metal salts thereof may also be used as antioxidant
additives.
[0120] The lubricant composition according to the invention may
contain any type of antioxidant additive known to those skilled in
the art. Advantageously, the lubricant composition comprises at
least one ash-free antioxidant additive.
[0121] Advantageously also, a lubricant composition according to
the invention may comprise from 0.1% to 2% by weight, relative to
the total weight of the composition, of at least one antioxidant
additive.
[0122] As regards the detergent additives, they generally make it
possible to reduce the formation of deposits on the surface of
metal parts by dissolving the oxidation and combustion
by-products.
[0123] The detergent additives that may be used in a lubricant
composition according to the invention are generally known to those
skilled in the art. The detergent additives may be anionic
compounds comprising a long lipophilic hydrocarbon-based chain and
a hydrophilic head. The associated cation may be a metal cation of
an alkali metal or alkaline-earth metal.
[0124] The detergent additives are preferentially chosen from
alkali metal or alkaline-earth metal salts of carboxylic acids,
sulfonates, salicylates and naphthenates, and also phenate salts.
The alkali metals and alkaline-earth metals are preferentially
calcium, magnesium, sodium or barium. These metal salts generally
comprise the metal in a stoichiometric amount or in excess, thus in
an amount greater than the stoichiometric amount. They are then
overbased detergent additives; the excess metal giving the
overbased nature to the detergent additive is then generally in the
form of a metal salt that is insoluble in the base oil, for example
a carbonate, a hydroxide, an oxalate, an acetate or a glutamate,
preferentially a carbonate.
[0125] A lubricant composition according to the invention may
comprise from 0.5% to 8% by weight and preferably from 0.5% to 4%
by weight of detergent additive relative to the total weight of the
lubricant composition.
[0126] Advantageously, a lubricant composition according to the
invention may comprise less than 4% by weight of detergent
additive(s), in particular less than 2% by weight, notably less
than 1% by weight, or may even be free of detergent additive.
[0127] As regards the pour-point depressant (PPD) additives, they
make it possible, by slowing down the formation of paraffin
crystals, to improve the cold-weather behavior of the lubricant
composition according to the invention.
[0128] Examples of pour-point depressants that may be mentioned
include polyalkyl methacrylates, polyacrylates, polyarylamides,
polyalkylphenols, polyalkylnaphthalenes and polyalkylstyrenes.
[0129] As regards the dispersants, they ensure the holding in
suspension and the removal of insoluble solid contaminants
constituted by the oxidation by-products that are formed when the
lubricant composition is in service. They may be chosen from
Mannich bases, succinimides and derivatives thereof.
[0130] In particular, a lubricant composition according to the
invention may comprise from 0.2% to 10% by weight of dispersant(s)
relative to the total weight of the composition.
[0131] Additional viscosity index (VI) enhancers, other than the
hydrogenated copolymers of diene and of aromatic vinyl, may also be
present in a lubricant composition in accordance with the present
invention. These viscosity index (VI) enhancers may be present in a
composition in accordance with the present invention in contents
which do not disrupt the effect desired in the context of the
present invention, namely the CIFE effect. These additional
viscosity index (VI) enhancers, in particular the additional
viscosity index-enhancing polymers, make it possible to ensure good
cold-weather behavior and a minimal viscosity at high temperature.
Examples of viscosity index-enhancing polymers that may be
mentioned include polymeric esters, homopolymers or copolymers of
olefins, such as ethylene or propylene, polyacrylates and
polymethacrylates (PMA).
[0132] In particular, a lubricant composition according to the
invention may comprise from 1% to 15% by weight of additional
viscosity index-enhancing additive(s) relative to the total weight
of the lubricant composition.
[0133] The antifoam additives may be chosen from polar polymers
such as polymethylsiloxanes or polyacrylates.
[0134] In particular, a lubricant composition according to the
invention may comprise from 0.01% to 3% by weight of antifoam
additive(s) relative to the total weight of the lubricant
composition.
[0135] The additive packs ready to be incorporated into a lubricant
composition comprise between 20% and 30% by weight of a diluent
consisting of base oil. The weight percentage of additive pack
relative to the weight of the lubricant composition in accordance
with the invention is at least 5%, the diluent being included in
this percentage.
[0136] According to one embodiment, the lubricant composition in
accordance with the invention comprises from 10% to 25% by weight,
notably from 10% to 20% by weight and more particularly from 13% to
18% by weight of an additive pack, relative to the weight of the
composition.
[0137] Characterization of the Lubricant Composition in Accordance
with the Invention
[0138] Preferably, a composition in accordance with the present
invention has a kinematic viscosity at 100.degree. C. of between
9.3 and 16.3 cSt measured by the standard ASTM D445 (grade SAE 30
and 40).
[0139] According to a particular embodiment, the grade according to
the classification SAEJ300 of a lubricant composition according to
the invention is chosen from 5W30, 10W30, 10W40 and 15W40.
[0140] According to a particular embodiment, a composition in
accordance with the present invention has a viscosity index VI of
between 140 and 165.
[0141] In the context of the present invention, the viscosity index
is measured according to the standard ASTM D2270-93, as is the case
in example 1 below. According to a particular embodiment of the
invention, the use, which is the subject of the invention, is also
characterized in that the measured kinematic viscosity of said
lubricant composition decreases by at least 0.5 mm.sup.2/s,
preferably by at least 0.6 mm.sup.2/s, even more preferably by at
least 0.8 mm.sup.2/s, for example by at least 1 mm.sup.2/s, when
said lubricant composition is used in the test described below,
relative to the initial kinematic viscosity before using said
lubricant composition in said test:
[0142] 150 g of lubricant composition are placed in a ventilated
oven heated at 150.degree. C. for 504 hours. On conclusion of this
test, a sample of the lubricant composition is taken and the
kinematic viscosity of this composition at 100.degree. C. according
to the standard ASTM D445-97 (mm.sup.2/s) is measured.
[0143] Examples of this decrease in kinematic viscosity observed
for the compositions in accordance with the present invention after
the thermal stability test are given in example 2.
[0144] Use of the Copolymers for Preparing a Lubricant
Composition
[0145] The lubricant compositions in accordance with the invention
find a particularly advantageous application as lubricants for the
various components of an industrial vehicle, such as the engines,
the transmission systems (gearbox and transfer box), the hydraulic
circuits and other secondary components, and notably for an
industrial vehicle engine, in particular a diesel engine.
[0146] They make it possible, by virtue of their viscosity
properties, not only to lubricate these various components but also
to extend the intervals between oil changes and to achieve fuel
savings.
[0147] Process for Preparing a Lubricant Composition
[0148] A lubricant composition in accordance with the invention may
be prepared according to the conventional methods known to those
skilled in the art.
[0149] The invention will now be described by means of the examples
that follow, which are, needless to say, given as nonlimiting
illustrations of the invention.
EXAMPLES
Example 1: Preparation of the Lubricant Compositions
[0150] Table 1 below shows the detail of the lubricant compositions
according to the invention (LC) and of the comparative compositions
(CC), for which the contents are expressed as mass percentages, and
also the physicochemical properties thereof.
[0151] The lubricant compositions are obtained by simple mixing at
room temperature of the following components:
TABLE-US-00002 TABLE 1 CC1 CC2 LC1 LC2 LC3 LC4 LC5 LC6 CC3 CC4 Base
oil 1 .sup.(1) 5.1 0 0 0 0 0 0 0 0 0 Base oil 2 .sup.(2) 34.5 33.3
34.5 34.8 25.1 26.7 38.9 39.4 35.3 36.2 Base oil 3 .sup.(2) 44 39.6
44 44 44 44 44 44 44 44 Additive pack .sup.(3) 16.2 16.2 16.2 16.2
16.2 16.2 16.2 16.2 16.2 16.2 Pour point 0.2 0.2 0.2 0.2 0.2 0.2
0.2 0.2 0.2 0.2 depressant additive .sup.(4) Polymer 1 .sup.(5) 0
10.7 0 0 0 0 0 0 0 0 Polymer 2 .sup.(6) 0 0 0 0 0 12.8 0 0 0 0
Polymer 3 .sup.(7) 0 0 0 0 0 0 0.7 0 0 0 Polymer 4 .sup.(8) 0 0 0
4.8 0 0 0 0 0 0 Polymer 5 .sup.(9) 0 0 5.1 0 0 0 0 0 0 0 Polymer 6
.sup.(10) 0 0 0 0 14.5 0 0 0 0 0 Polymer 7 .sup.(11) 0 0 0 0 0 0 0
0.2 0 0 Polymer 8 .sup.(12) 0 0 0 0 0 0 0 0 4.3 0 Polymer 9
.sup.(13) 0 0 0 0 0 0 0 0 0 3.4 KV 40.degree. C. 54.3 92.5 84.2
84.9 77.1 74.9 86.0 79.3 70.3 75.6 ASTM D445-97 (mm.sup.2/s) KV
100.degree. C. 8.4 12.1 12.3 12.4 12.2 12.4 12.4 12.4 12.3 12.4
ASTM D445-97 (mm.sup.2/s) Viscosity index 128 123 142 142 155 164
140 153 175 163 (VI) ASTM D2270-93 .sup.(1) Base oil 1 is a base
oil from group I (kinematic viscosity at 100.degree. C. measured
according to the standard ASTM D445 = 5.30 mm.sup.2/s) commercially
available, for example, from the company TOTAL under the trade name
150 NS .sup.(2) Base oil 2 is a base oil from group II (kinematic
viscosity at 100.degree. C. measured according to the standard ASTM
D445 = 4.10 mm.sup.2/s) commercially available, for example, from
the company Chevron under the trade name 100R Base oil 3 is a base
oil from group II (kinematic viscosity at 100.degree. C. measured
according to the standard ASTM D445 = 6.4 mm.sup.2/s) commercially
available, for example, from the company Chevron under the trade
name 220R .sup.(3) A conventional additive pack comprising, at
least, a dispersant, detergents, an antiwear agent, antioxidants
and friction modifiers .sup.(4) A pour point depressant additive
which is a conventional polymethacrylate polymer commercially
available from the company Evonik under the trade name Viscoplex
.RTM. .sup.(5) Polymer 1 (outside the invention) is a
polyisobutylene polymer commercially available from the company
Ineos under the trade name Indopole .RTM. H300 .sup.(6) Polymer 2
is a hydrogenated styrene-butadiene polymer commercially available
from the company Lubrizol under the trade name Lz .RTM. 7418
.sup.(7) Polymer 3 is a hydrogenated styrene-butadiene polymer
commercially available from the company Afton under the trade name
Hitec .RTM. 6005 .sup.(8) Polymer 4 is a star hydrogenated
isoprene-styrene polymer commercially available from the company
Infineum under the trade name SV .RTM. 301 .sup.(9) Polymer 5 is a
star hydrogenated isoprene-styrene polymer commercially available
from the company Infineum under the trade name SV .RTM. 261
.sup.(10) Polymer 6 is a linear hydrogenated isoprene-styrene
polymer commercially available (from the company Infineum under the
trade name SVC) 154 .sup.(11) Polymer 7 is a hydrogenated
isoprene-styrene polymer commercially available from the company
Lubrizol under the trade name Lz .RTM. 7306 .sup.(12) Polymer 8 is
a polymethacrylate polymer commercially available from the company
Evonik under the trade name Viscoplex .RTM. 6-950 .sup.(13) Polymer
9 is a polymethacrylate polymer commercially available from the
company Evonik under the trade name Viscoplex .RTM. 6-850 .sup.(14)
Polymer 10 is a polymethacrylate polymer commercially available
from the company Sanyo Chemical under the trade name AClub .RTM.
V10-70
Example 2: Compared Viscosity Behavior for Illustrating the
Decrease in Viscosity in the Course of its Use
[0152] The present examples were performed for the purpose of
demonstrating the selection made from among the viscosity
index-enhancing polymers, for preparing lubricant compositions
which have CIFE properties as targeted in the context of the
present invention.
[0153] The tests performed are the following: [0154] Thermal
stability at 150.degree. C.
[0155] 150 g of lubricant composition are placed in a ventilated
oven heated at 150.degree. C. for 504 hours. On conclusion of this
test, a sample of the lubricant composition is taken and the
kinematic viscosity of this composition at 100.degree. C. is
measured according to the standard ASTM D445-97 (mm.sup.2/s).
[0156] The kinematic viscosities of the comparative compositions
and of the compositions according to the invention as described in
table 1, which were first subjected to the thermal stability test
as described above, were measured and collated in table 2
below.
TABLE-US-00003 TABLE 2 KV 100.degree. C. KV 100.degree. C. ASTM
D445-97 ASTM D445-97 (mm.sup.2/s) (mm.sup.2/s) before after thermal
stability thermal stability test test at 150.degree. C. CC1 8.4 8.6
CC2 12.1 13.1 LC1 12.3 10.6 LC2 12.4 10.3 LC3 12.2 10.9 LC4 12.4
10.8 LC5 12.4 11.8 LC6 12.4 10.8 CC3 12.3 12.7 CC4 12.4 13.1
[0157] It emerges from these results that the compositions
according to the invention have a kinematic viscosity at
100.degree. C., measured according to the standard ASTM D445-97
after the thermal stability test, which decreases over time
relative to their kinematic viscosities measured before the
stability test.
[0158] It also emerges from these results that the comparative
compositions have a kinematic viscosity at 100.degree. C., measured
according to the standard ASTM D445-97 after the thermal stability
tests, which increases over time relative to their kinematic
viscosities measured before the stability tests.
[0159] These results illustrate the change in the decrease in
viscosity of the compositions according to the invention as a
function of time and, consequently, the behavior as required
according to the present invention, namely the decrease in
viscosity as a function of time of the compositions in accordance
with the invention, during a thermal shear, in contrast with the
comparative compositions for which an increase in viscosity is
observed during a thermal shear.
[0160] These results also demonstrate the impact of the chemistry
of the polymers on the viscosity profile of the lubricant
compositions during a thermal shear.
[0161] Specifically, the polymers according to the invention make
it possible to obtain compositions whose viscosity decreases during
a thermal shear, in contrast with the polymers outside the
invention, which, when they are in a lubricant composition, do not
make it possible to reduce the viscosity of said composition during
a thermal shear; quite to the contrary, the viscosity of said
composition increases.
[0162] Mechanical Stability
[0163] Viscosity Measurement at 100.degree. C. of the Oil Sheared
after Bosch 90 Cycles Tests (KV100.degree. C. Bosch 90 Cycles)
[0164] The compositions described in example 1 were subjected to a
mechanical shear (Bosch 90 cycles injector test).
[0165] FIG. 1 illustrates the phenomenon of the decrease in
viscosity of the compositions as a function of the Bosch cycle
number.
[0166] This figure also illustrates the behavior as required
according to the present invention, including after a mechanical
shear.
[0167] As a general conclusion to example 2, following the thermal
and mechanical shears, it is observed that only the lubricant
compositions in accordance with the invention have viscosity values
lower than that of the same composition before shear.
[0168] Consequently, the kinematic viscosities of the compositions
according to the invention after thermal and mechanical stability
tests do not increase over time, but quite to the contrary
decrease. This demonstrates that the compositions according to the
invention correspond to the CIFE properties. Specifically, the more
the viscosity of a composition increases, the more the various
lubricated components of the engine consume energy and,
consequently, fuel.
Example 3: Engine Tests
[0169] Engine tests were performed on the lubricant compositions as
described in example 1.
[0170] Test Principle
[0171] The engine tests are performed on a Volvo D11 5 engine (440
HP), for which the thermal management of the oil is deliberately
set at 118.degree. C. of oil sump temperature, in order to be
representative of hot running conditions and thus to promote the
shear of the lubricant compositions via the thermal effect.
[0172] Each lubricant composition test is characterized as follows:
[0173] Step 1: fresh oil, measurement of fuel consumptions on a
WHSC normalized cycle (World Harmonized Stationary Cycle, 13
stabilized mode points, full regime). [0174] Step 2: aging of the
lubricant composition over an endurance cycle, which consists in
reproducing on an engine test bed a dynamic road cycle
representative of road use, which was recorded under real
conditions by a heavy-duty vehicle OEM. The test lasted 300 hours.
The dynamism of the test road cycle is favorable to shear of the
tested lubricant compositions by a mechanical effect. The fuel
consumption is monitored in dynamic mode throughout the endurance
test as a guide. Intermediate oil samples are taken during the test
to perform various measurements (kinematic viscosity at 100.degree.
C. in particular, shown in FIGS. 2 and 3). [0175] Step 3: after the
endurance test, the lubricant composition present in the test
engine is once again measured according to the WHSC normalized
cycle in order to characterize the fuel consumptions after the
endurance test. The fuel consumption results for each of the 13
measurement mode points (regime/load) are compared with the results
obtained from step 1, in order to evaluate the CIFE performance of
the tested lubricant composition.
[0176] It is thus the result obtained from step 3 which will
characterize the CIFE potential of the tested lubricant composition
relative to a reference lubricant tested under the same conditions
(steps 1, 2, 3). The savings in fuel consumption are established on
the entire engine field.
[0177] Results Composition LC2 was evaluated before and after the
endurance test on the WHSC cycle. FIG. 2 shows the measurement
curve for the viscosity at 100.degree. C. of this composition LC2
during the engine test. A 0.87% saving in fuel consumption was
measured on the sheared oil which underwent the endurance test
relative to the oil before the endurance test. This saving is
significant relative to the threshold of the method for
discrimination between two products (0.34%).
[0178] A comparative lubricant composition CC5 was then evaluated
according to the same criteria.
[0179] Said comparative lubricant composition is detailed in table
3 below:
[0180] The contents are expressed as mass percentages.
TABLE-US-00004 TABLE 3 CC5 Base oil 2 .sup.(2) 30 Base oil 3
.sup.(2) 38.6 Additive pack .sup.(3) 16.2 Pour point depressant
additive .sup.(4) 0.2 Polymer 10 .sup.(14) 15 KV 40.degree. C.
82.25 ASTM D445-97 (mm.sup.2/s) KV 100.degree. C. 12.39 ASTM
D445-97 (mm.sup.2/s) Viscosity index (VI) 147 ASTM D2270-93
[0181] The meanings of the components defined by indices are those
given in example 1.
[0182] A 0.25% excess fuel consumption was measured on the sheared
oil which underwent the endurance test relative to the oil before
the endurance test. FIG. 3 shows the measurement curve for the
viscosity at 100.degree. C. of this comparative composition during
the engine test.
[0183] This example very clearly shows the difference in behavior
in terms of viscosity and more particularly the satisfaction of the
CIFE characteristic required in the context of the invention, for
the lubricant compositions in accordance with the invention, namely
those comprising at least one polymer for improving the viscosity
index chosen from hydrogenated copolymers of diene and of aromatic
vinyl, compared with lubricant compositions comprising polymers of
another nature which improve the viscosity index.
Example 4: Compared Viscosity Behavior for Illustrating the
Decrease in Viscosity in the Course of its Use in the Gearbox and
in the Hydraulic Circuit
[0184] The present examples were performed for the purpose of
demonstrating the selection made from among the viscosity
index-enhancing polymers, for preparing lubricant compositions
which have CIFE properties when they are used in the gearbox and in
the hydraulic circuit.
[0185] It is known that the temperatures prevailing in the gearbox
and in the hydraulic circuit are lower than those in the engine and
generally do not exceed 110.degree. C. It is also known that the
interval between oil changes is longer for the gearbox and the
hydraulic circuits when compared with that for the engine.
Consequently, this thermal stability test performed at a lower
temperature and over a period corresponding to the interval between
oil changes makes it possible to demonstrate the viscosity behavior
of the compositions according to the invention in gearboxes and
hydraulic circuits.
[0186] The tests performed are the following:
[0187] Thermal Stability at 80.degree. C.
[0188] 150 g of lubricant composition are placed in a ventilated
oven heated at 80.degree. C. for 1008 hours. On conclusion of this
test, a sample of the lubricant composition is taken and the
kinematic viscosity of this composition at 100.degree. C. is
measured according to the standard ASTM D445-97 (mm.sup.2/s).
[0189] Thermal Stability at 100.degree. C.
[0190] 150 g of lubricant composition are placed in a ventilated
oven heated at 100.degree. C. for 1008 hours. On conclusion of this
test, a sample of the lubricant composition is taken and the
kinematic viscosity of this composition at 100.degree. C. is
measured according to the standard ASTM D445-97 (mm.sup.2/s).
[0191] The kinematic viscosities of the comparative compositions
and of the compositions according to the invention as described in
table 1, which were first subjected to the thermal stability test
as described above, were measured and collated in table 4
below.
TABLE-US-00005 TABLE 4 KV 100.degree. C. KV 100.degree. C. KV
100.degree. C. ASTM D445-97 ASTM D445-97 ASTM D445-97 (mm.sup.2/s)
after (mm.sup.2/s) after (mm.sup.2/s) before thermal stability
thermal stability thermal stability test test at 80.degree. C. test
at 100.degree. C. CC2 12.5 12.5 12.5 LC1 12.3 12.1 11.8 LC2 12.3
11.8 11.0
[0192] It emerges from these results that the compositions
according to the invention have a kinematic viscosity at
100.degree. C., measured according to the standard ASTM D445-97
after the thermal stability test, which decreases over time
relative to their kinematic viscosities measured before the
stability test.
[0193] It also emerges from these results that the comparative
composition has a kinematic viscosity at 100.degree. C., measured
according to the standard ASTM D445-97 after the thermal stability
tests, which remains constant over time relative to its kinematic
viscosity measured before the stability tests.
[0194] These results illustrate the change in the decrease in
viscosity of the compositions according to the invention as a
function of time and, consequently, the behavior as required
according to the present invention, namely the decrease in
viscosity as a function of time of the compositions in accordance
with the invention, during a thermal shear, in contrast with the
comparative composition for which maintenance of the viscosity
during a thermal shear is observed.
[0195] These results also demonstrate the impact of the chemistry
of the polymers on the viscosity profile of the lubricant
compositions during a thermal shear.
[0196] Specifically, the polymers according to the invention make
it possible to obtain compositions whose viscosity decreases during
a thermal shear, in contrast with the polymers outside the
invention, which, when they are in a lubricant composition, do not
make it possible to reduce the viscosity of said composition during
a thermal shear.
[0197] In conclusion, following the thermal shears, it is observed
that only the lubricant compositions in accordance with the
invention have viscosity values lower than that of the same
composition before shear.
[0198] Consequently, this demonstrates that the compositions
according to the invention correspond to the CIFE properties when
the composition is used in the gearbox and in the hydraulic
circuit. Specifically, the more the viscosity of a composition
increases, the more the various lubricated components of the
gearbox and of the hydraulic circuit consume energy and,
consequently, fuel.
Example 5
[0199] Compositions LC1 and LC2 according to the invention
underwent a KRL shear test for 3 hours and 20 hours according to
the standard CEC-L-45-A-99. This test is representative of the
shear conditions of gearboxes when it is performed over a period of
20 hours and of the conditions of the hydraulic circuit when it is
performed over 3 hours. The viscosities before the test and after
the test were measured at 100.degree. C. and at 40.degree. C.
(standard ASTM D445-97), and are collated in table 5 below, in
which the viscosities are indicated in mm.sup.2/s.
TABLE-US-00006 TABLE 5 LC1 LC2 KV 100.degree. C. before the KRL
test 12.3 12.4 KV 100.degree. C. after the KRL 3 h test 9.1 9.0 KV
100.degree. C. after the KRL 20 h test 8.3 8.2 KV 40.degree. C.
before the KRL test 84.2 84.9 KV 40.degree. C. after the KRL 3 h
test 59.8 59.4 KV 40.degree. C. after the KRL 20 h test 54.0
53.2
[0200] It emerges from these results that the compositions
according to the invention have a kinematic viscosity at
100.degree. C., measured according to the standard ASTM D445-97
after the KRL shear test, which decreases over time relative to
their kinematic viscosities measured before the shear test.
[0201] These results illustrate the change in the decrease in
viscosity of the compositions according to the invention as a
function of time and, consequently, the behavior as required
according to the present invention, namely the decrease in
viscosity as a function of time of the compositions in accordance
with the invention, during a shear such as that which a lubricant
composition undergoes in a gearbox and a hydraulic circuit, notably
of an industrial vehicle, in particular of a diesel engine
industrial vehicle.
* * * * *