Description
The invention relates to the field of lubricating compositions for motor vehicles. The
5 invention provides a lubricating composition of a grade according to the SAEJ300
classification defined by the formula (X) W (Y) wherein X represents 0 or 5 and Y
represents an integer ranging from 4 to 20. This lubricating composition comprises at
least one polyalphaolefinic oil (PAO), from 10 to 80% by weight of the composition of at
least one oil of group V and at least one comb polymer. The invention also relates to the
10 use of this lubricating composition for improving the Fuel Eco (FE) of a lubricant or for
reducing the fuel consumption of an engine, in particular a motor vehicle engine, notably a
motor of a hybrid vehicle.
The needs for high performance lubricants increase. In particular, because of the
15 conditions of use for which severity increases, for example because of very high
temperatures or very high mechanical stresses.
The spacing out of the oil changes and the reduction in the size of the lubrication systems
also cause an increase in the need of high performance lubricants.
The energy efficiency and notably the improvement of the Fuel Eco (FE) of the lubricants
20 or the reduction of the fuel consumption of the engines, in particular vehicle engines, are
increasingly significant goals and lead to the increasing use of high performance
lubricants.
The high performance lubricants should therefore have improved properties, in particular
as regards the cinematic viscosity, the viscosity index, the volatility, the dynamic viscosity
25 or the cold pour point.
The thermal stability and the resistance to oxidation are also properties to be improved for
high performance lubricants.
Reduced toxicity and good miscibility with other lubricants or other materials are also
properties to be sought for high performance lubricants.
30 These needs are particularly increased during the lubrication of an engine of a hybrid
vehicle, in particular as regards the reduction of the friction processes within the engine.
The improvement of the conditions of use, for example at particular operating
temperatures, should also be targeted, in particular during the rise in temperature of the
engine.
35 In order to improve the energy efficiency of automobile engines via the reduction of the
friction processes, the engine lubricants may be used with a viscosity grade increasingly
2
fluid. This phenomenon is all the more significant when the engines operate under low
temperature cycles as often imposed by urban paths in most of the large cities of the
planet. And this need is all the more significant for hybrid engines. Beyond the reduction
in the viscosity grade other solutions give the possibility of increasing the FE gains
5 provided by the engine lubricant.
The lubricating compositions for an engine should also give the possibility of improving the
cleanliness of the engine. They should also be compliant with the limits set by the
automotive industry.
10 Therefore there exists a need for high perfonmance lubricants giving the possibility of
providing a solution to all or part of the problems of lubricants of the state of the art.
15
Thus, the invention provides a lubricant composition of a grade according to the SAEJ300
classification defined by the formula (I)
wherein
• X represents 0 or 5;
(X) W (Y)
(I)
• Y represents an integer ranging from 4 to 20; and
20 comprising
25
30
(a) at least one polyalphaolefinic oil (PAO) for which the cinematic viscosity measured
at 1 OO"C according to the ASTM 0445 standard ranges from 1.5 to 8 mm2 s·';
(b) from 10 to 80 % by weight of the composition of at least one oil of group V for
which the cinematic viscosity measured at 1 00" C according to the ASTM 0445
standard ranges from 1.5 to 8 mm2 s·1
;
(c) at least one comb polymer for which the pendant chains comprise at least 50
carbon atoms ·end selected from copolymers of at least one polyolefin and of at
least one poly(alkyl)methacrylate; the copolymers of at least one polyolefin and of
at least one poly(alkyl)acrylate.
The lubricating composition according to the invention has a particularly advantageous
viscosity grade. The viscosity grade of the lubricant composition according to the
invention may notably be selected from among
• a grade according to the SAEJ300 classification defined by the formulae (II) or (Ill)
OW(Y) 5W(Y)
(II) (Ill)
3
wherein Y represents an integer ranging from 4 to 20, in particular ranging from 4
to 16 or from 4 to 12; or
• a grade according to the SAEJ300 classification defined by the formulae (IV} or (V)
(X)W8 (X)W12
(IV) (V)
wherein X represents 0 or 5.
5 Preferably, the grade according to the SAEJ300 classification of the lubricant composition
according to the invention is selected from among OW4, OW8, OW12, OW16, OW20, 5W4,
5W8, 5W12, 5W16, 5W20. More preferably, the lubricant composition according to the
invention has a grade according to the SAEJ300 classification of OW12.
10 Also preferably, the cinematic viscosity measured at 40 "C according to the ASTM 0445
standard of the lubricant composition according to the invention ranges from 12 to 30
mm2 s·1
, preferably from 14 to 25 mm2 s-1
.
The composition according to the invention comprises at least one polyalphaolefinic oil
15 (PAO), from 10 to 80% by weight of the composition of at least one oil of group V and at
least one comb polymer.
Preferably, the lubricant composition according to the invention comprises a PAO for
which the cinematic viscosity, measured at 100 "C according to the ASTM 0445 standard,
20 ranges from 1.5 to 6 mm2 s-1 or from 2 to 8 mm2 s·1 or further from 2 to 6 mm2 _s-1
.
The average weight molecular mass of the PAO may vary quite considerably. Preferably,
the average weight molecular mass of the PAO is less than 500 Oa. The weight average
molecular mass of the PAO may also range from 50 to 500 Oa, from 50 to 350 Oa or
further from 50 to 300 Oa.
25 Also preferably, th€ lubricant composition according to the invention comprises a
lightweight PAO, in particular a PAO for which the cinematic viscosity at 100"C, measured
according to the ASTM 0445 standard, ranging from 3 to 4 mm2 .s·', and which comprises
more than 50 % by weight of 9-methyl-11-octyl-henicosane, a trimer of the 1-decene of
formula (A)
30
(A)
4
In addition to the PAO, the lubricant composition according to the invention comprises an
oil of group V in an amounts ranging from 10 to 80 % by weight of the lubricant
composition. Preferably, the lubricant composition according to the invention comprises
from 20 to 80%, from 20 to 60%, from 20 to 50% or from 30 to 80%, from 30 to 60%, from
5 30 to 50% by weight of the composition of an oil of group V. More preferably, the lubricant
composition according to the invention comprises from 35 to 45%, for example 40%, by
weight of the oil composition of group V.
Also preferably, the lubricant composition according to the invention comprises an oil of
group V selected from among a monoester, a diester, a polyester, an estolide, a
10 polyalkylene-glycol (PAG). Preferably, the oil of group V is selected from among a
monoester or a polyalkylene-glycol (PAG).
As a preferred monoester, mention may be made of a monoester of formula (B1 );
0
R1)lOR2
(61)
15 wherein
• R1 represents a saturated or unsaturated, linear or branched hydrocarbon
group comprising from 14 to 24 carbon atoms;
• R2 represents a linear or branched, saturated or unsaturated hydrocarbon
group comprising from 2 to 18 carbon atoms;
20 As a more preferred monoester, mention may be made of a monoester of formula (61)
wherein
• R1 is a saturated group and R2 is an unsaturated group; or
• R 1 is an unsaturated group and R2 is a saturated group; or
• R1 and R2 are saturated groups; or
25 • R1 and R2 are unsaturated groups; or further
30
one monoester of formula (61) wherein
• R1 represents a linear or branched saturated or unsaturated hydrocarbon
group, comprising from 14 to 20 carbon atoms, preferentially from 14 to 18
carbon atoms, more preferentially from 16 to i 8 carbon atoms; or
• R2 represents a linear or branched saturated or unsaturated hydrocarbon
group, comprising from 3 to 14 carbon atoms, preferentially from 4 to 12
carbon atoms, more preferentially from 4 to 10 carbon atoms; or
• R1 is a linear group and R2 is a branched group; or
' R1 is a branched group and R2 is a linear group; or
5
10
15
5
• R1 and R' are linear groups; or
• R1 and R2 are branched groups.
As a particularly preferred monoester, mention may be made of a monoester of formula
(81) in which only R', only R2 or R1 and R'are selected from among
• a linear saturated group;
• a branched saturated group comprising from 1 to 5 branched chains;
• a branched saturated group for which the branched chains comprised from 1
to 5 carbon atoms;
• a branched saturated group comprising from 1 to 5 branched chains and for
which the branched chains comprised from 1 to 5 carbon atoms.
As examples of preferred monoesters, mention may be made of
• stearates, preferably alkyl stearates and alkenyl stearates, more preferentially
C4-C10-alkyl stearates, in particular butyl stearate, pentyl stearate, hexyl
stearate, heptyl stearate, octyl stearate, nonyl stearate, decyl stearate;
• oleates, preferably alkyl oleates and alckenyl oleates, more preferentially C4-
Cwalkyl oleates, in particular butyl oleate, pentyl oleate, hexyl oleate, heptyl
oleate, octyl oleate, nonyl oleate, decyl oleate.
As examples of preferred monoesters, mention may also be made of alkene monoesters
and alkyl monoesters, preferably C,-C10-alkyl monoesters, in particular ethyl monoesters,
20 propyl monoesters, butyl monoesters, pentyl monoesters, hexyl monoesters.
As a preferred polyalkylene-glycol (PAG), mention may be made of a PAG of formula (82)
(82)
25 wherein
• R3 represents a linear and branched C,-C30-alkyl group;
• m and n represent independently an average number ranging from 1 to 5.
Preferably for the PAG of formula (82), R3 represents a group selected from among a
linear C8-alkyl group; a branched C8-alkyl group; a linear C9-alkyl group; a branched C9-
30 alkyl group; a linear C10-alkyl group; a branched Cw-alkyl group; a linear C,,-alkyl group; a
branched C11 -alkyl group; a linear C12-alkyl group; a branched C12-alkyl group; a linear
C13-alkyl group; a branched C13-alkyl group; a linear C1.-alkyl group; a branched C14-alkyl
group; a linear C15-alkyl group; a branched Cwalkyl group.
6
Also preferably for the PAG of formula (82),
• m is greater than or equal to n; or
• m represents an average number ranging from 2 to 4.5, notably an average
number ranging from 2 to 3.5; or
5 • n represents an average number ranging from 1.5 to 4, notably an average
number ranging from 1.5 to 3.
More preferably for the PAG of formula (82), m represents an average number equal to
2.5 and n represents an average number equal to 2 or m represents an average number
equal to 3.5 and n represents an average number equal to 2.8.
10 Advantageously for the lubricant composition according to the invention, the PAG of
formula (82) has
• a cinematic viscosity at 1 oooc, measured according to the ASTM 0445 standard,
ranging from 2.5 to 4.5 mm2 s.1
' or
• a viscosity index greater than 160 or comprised between 160 and 210; or
15 • a pour point of less than -40°C; or
• a dynamic viscosity (CCS) at -35°C, measured according to the ASTM 05293
standard of less than 1,200 mPa.s.
A preferred exemplary PAG is a PAG of formula (82) wherein m represents an average
number equal to 2.5 and n represents an average number equal to 2 and for which the
20 cinematic viscosity at 1 00°C, measured according to the ASTM 0445 standard, ranges
from 2.5 to 3.5 mm2.s-1
' the viscosity index is comprised between 160 and 180; the pour
point is less than -40 oc; the dynamic viscosity (CCS) at -35°C, measured according to
the ASTM 05293 standard is less than 500 mPa.s.
Another preferred exemplary PAG is a PAG of formula (82) wherein m represents an
25 average number equal to 3.5 and n represents an average number equal to 2.8 and for
which the cinematic viscosity at 100°C, measured according to the ASTM 0445 standard,
ranges from 3.5 to4.5-mm2.s·1
' the viscosity index is comprised between 180 and 210; the
pour point is less than -50°C; the dynamic viscosity (CCS) at -35°C, measured according
to the ASTM 05293 standard is less than 1 ,200 mPa.s.
30
As another polyalkylene-glycol (PAG), mention may be made of a polymer with blocks of
formula (83) or a random polymer of formula (83)
Rs
R40~0--h--H
R6
7
(B3)
wherein
• R4 represents a linear or branched C,-C30-alkyl group, preferably a linear or
branched c,-c1,_alkyl group;
5 • p represents a number ranging from 2 to 60, preferably from 5 to 30 or from 7 to
15;
• R5 and R6
, either identical or different, represent independently a hydrogen atom
or a C1-Cralkyl group.
As other particular polyalkylene-glycol groups (PAG), mention may be made of
1 0 o a polymer with blocks of formula (B4) or a random polymer of formula (B4)
15
20
25
30
R7
R40~0--h--H
Rs
(B4)
wherein
• R4 represents a linear or branched C,-C30-alkyl group, preferably a linear or
branched C8-C1ralkyl group;
• q represents a number ranging from 2 to 60, preferably from 5 to 30 or from 7
to 15;
• R7 and R8 represent a hydrogen atom; or R7 represents a hydrogen atom and
R8 represents a methyl group; or R7 represents a methyl group and R8
represents a hydrogen atom; wherein R7 and R8 represent a methyl group; or
R7 represents an ethyl group and R8 represents a hydrogen atom; or R7
represents a hydrogen atom and R8 represents an ethyl group;
o a polymer with blocks of formula (B5) or a random polymer of formula (B5)
Rg R12
R40~0-MCo---+t-H
R 10 R 11
(85)
wherein
• R4 represents a linear or branched C1-C30-alkyl group, preferably a linear or
branched C8-C12-alkyl group;
• rand t represent independently a number ranging from 1 to 30, preferably from
2 to 15 or from 2 to 8;
8
• R9 and R10 represent a hydrogen atom; or R9 represents a hydrogen atom and
R10 represents a methyl group; or R9 represents a methyl group and R10
represents a hydrogen atom; or R9 and R10 represent a methyl group; or R9
represents an ethyl group and R10 represents a hydrogen atom; or R9
5 represents a hydrogen atom and R10 represents an ethyl group;
10
15
20
• R11 and R12 represent a hydrogen atom; or R11 represents a hydrogen atom
and R12 represents a methyl group; or R11 represents a methyl group and R12
represents a hydrogen atom; or R11 and R12 represent a methyl group; or R11
represents an ethyl group and R12 represents a hydrogen atom; or R11
represents a hydrogen atom and R12 represents an ethyl group.
Like other particular polyalkylene-glycol (PAG) groups, mention may be made of a
polymer with blocks of formula (86) or a random polymer of formula (86)
(86)
wherein
• R13 represents a linear or branched C8-C12-alkyl group;
• v represents a number ranging from 2 to 6;
• w represents a number ranging from 2 to 5.
In addition to a PAO and an oil of group V, the lubricant composition according to the
invention comprises a comb polymer.
Preferably, the comb polymer comprises pendant chains obtained by polymerization or by
25 copolymerization of olefins. In a more preferred way, the comb polymer comprises
pendant chains obtained by polymerization or by copolymerization of olefins comprising
from 8 to 17 carbon atoms, in particular of olefins selected from among styrenes,
substituted styrenes, butadiene with an addition in 1 ,4, butadiene with an addition in 1 ,2,
the compounds of formula (C1)
30
(C1)
5
10
15
20
25
9
wherein Q 1 and Q 2 represent independently a hydrogen atom or a C1-C18-alkyl group.
More preferably, the comb polymer is prepared by copolymerization
• of an olefinic monomer of formula (C2)
Q4
Q3-+--L~L2~0nA
0
(C2)
wherein
o Q3 represents a linear or branched C,-C8-alkyl group; a C3-C8-cycloalkyl
group; a Cs-C1o-aryl group;
o Q4 represents a hydrogen atom or a methyl group;
o L 1 represents a residue of 1,4 addition of butadiene; a residue of 1,4
addition of butadiene substituted with at least one C,-C6-alkyl group; a
residue of vinyl addition of styrene; a residue of vinyl addition of styrene
substituted with at least one C1-C6-alkyl group;
o L 2 represents a residue of vinyl addition of butadiene; a residue of vinyl
addition of butadiene substituted with a C1-Coalkyl group; a residue of vinyl
addition of styrene; a residue of vinyl addition of styrene substituted with at
least one C1-C6-alkyl group;
o k and j represent independently 0 or an integer ranging from 1 to 3,000 and
the sum (k + j) is equal to an integer ranging from 7 to 3,000, preferably
ranging from 10 to 3,000; et
• of a acrylic-alkyl ester monomer or methacrylic-alkyl ester of formula (C3)
Q5
wherein
)yo'd
0
(C3)
o Q5 represents a hydrogen atom or a methyl group;
o Q6 represents a linear or branched C1-C26-alkyl group.
More preferably, Q3 represents a phenyl group or a linear or branched butyl group, in
particular an n-butyl group.
30 In a more particularly preferred way, the comb polymer is prepared by copolymerization
5
10
• of an olefinic monomer of formula (C4)
Q7
(C4)
wherein
o Q7 represents a C1-C6-alkyl; a C6-aryl group;
0~
0
o Q8 represents a hydrogen atom or a methyl group;
o Q9
, Q10 et Q11 represent independently a hydrogen atom or a C1-C18-alkyl
group;
o x, y and z represent independently 0 or an integer ranging from 1 to 3,000
10 and the sum (x + y + z) is equal to an integer ranging from 7 to 3,000,
preferably ranging from 10 to 3,000; and
15
• of an acrylic-alkyl ester monomer or methacrylic-alkyl ester of formula (C3)
Qs
wherein
)yo'd
0
(C3)
o Q5 represents a hydrogen atom or a methyl group;
o Q 6 represents a linear or branched C1-C26-alkyl group.
More preferably, Q7 represents a phenyl group or a linear or branched butyl group, in
particular an n-butyl group.
20 In a more particularly preferred way, the comb polymer is prepared by copolymerization
• of an olefinic monomer of formula (C5)
(C5)
wherein
25 o Q8 represents a hydrogen atom or a methyl group;
5
11
o x and y represent independently 0 or an integer ranging from 1 to 3,000
and the sum (x + y + z) is equal to an integer ranging from 7 to 3,000,
preferably ranging from 10 to 3,000; and
• of an acrylic-alkyl ester monomer or methacrylic-alkyl ester of formula (C3)
Q5
wherein
)yo"o"
0
(C3)
o Q5 represents a hydrogen atom or a methyl group;
o Q6 represents a linear or branched C1-C26-alkyl group.
10 An example of a comb polymer is the product Viscoplex 3-200 (Evonik Corporation).
Within the lubricant composition according to the invention, the respective amounts (a) of
PAO, (b) of an oil of group V and (c) of a comb polymer may vary. Preferably, the weight
ratio (alb) between the polyalphaolefinic oil (PAO) (a) and the oil of group V (b) ranges
15 from 0.1 to 4, preferably from 0.3 to 3.6.
The lubricant composition according to the invention has a particularly high VI.
Preferably, the VI of the lubricant composition according to the invention is greater than
220. More preferably, the VI of the lubricant composition according to the invention is
20 greater than 250, or even greater than 270 or than 300.
Generally, the lubricant composition according to the invention may comprise other base
oils, mineral, synthetic or natural, animal or vegetable oils, adapted to its use.
The base oils.used.inlhe.l.ubricant compositions according to the invention may be oils of
25 mineral or synthetic origins belonging to the groups I to V according to the classes defined
by the API classification (or their equivalents according to the A TIEL classification) (table
A) or mixtures thereof.
Contents of
Viscosity index
saturated Sulfur content
substances
(VI)
Group I <90% > 0.03% 80 <;VI < 120
Mineral oils
Group II
<:90% <; 0.03% 80 <;VI< 120
Hydrocracked oils
12
Group Ill
Hydrocracked or hydro- :o-90% "0.03% "'120
isomerized oils
Group IV Polyalphaolefins (PAO)
Group V
Esters and other bases not included in the groups I to
IV
Table A
The mineral base oils according to the invention include all types of bases obtained by
atmospheric and in vacuo distillation of crude oil, followed by refining operations such as
5 extraction with a solvent, de-asphalting, de-waxing with a solvent, hydro-treatment,
hydrocracking, hydroisomerization and hydrofinishing.
Mixtures of synthetic and mineral oils may also be used.
Generally there does not exit any limitation as to the use of different lubricant bases for
producing the lubricant compositions according to the invention, except that they have to
1 0 have properties, notably viscosity properties, a viscosity index, a sulfur content, a
resistance to oxidation, adapted to the use for engines or for vehicle transmissions.
The base oils of the lubricant compositions according to the invention may also be
selected from among synthetic oils, such as certain esters of carboxylic acids and of
alcohols, and from among polyalphaolefins. The polyalphaolefins used as base oils are
15 for example obtained from monomers comprising from 4 to 32 carbon atoms, for example
from octene or decene, and for which the viscosity at 1 OO'C is comprised between 1.5
and 15 mm2 s·1 according to the ASTM 0445 standard. Their average molecular mass is
generally comprised between 250 and 3,000 according to the ASTM 05296 standard.
20 The lubricant composition according to the invention may comprise at least 50% by mass
of base oils based .on the total mass of the composition. More advantageously, the
lubricant composition according to the invention comprises at least 60% by mass, or even
at least 70% by mass, of base oils based on the total mass of the composition. In a more
particularly advantageous way, the lubricant composition according to the invention
25 comprises from 75 to 99.9% by mass of base oils based on the total mass of the
composition.
The invention also provides a lubricant composition for engines of vehicles comprising at
least one lubricant composition according to the invention, at least one base oil and at
30 least one additive.
13
Many additives may be used for this lubricant composition according to the invention.
The preferred additives for the lubricant composition according to the invention are
selected from among detergent additives, anti-wear additives, friction modifier additives,
extreme pressure additives, dispersants, enhancers of the pour point, anti-foam agents,
5 thickeners and mixtures thereof.
Preferably, the lubricant composition according to the invention comprises at least one
anti-wear additive, at least one extreme pressure additive or mixtures thereof.
The anti-wear additives and the extreme pressure additives protect the friction surfaces by
forming a protective film adsorbed on these surfaces.
10 There exist a large variety of anti-wear additives. Preferably for the lubricant composition
according to the invention, the anti-wear additives are selected from among phosphorussulfur-
containing additives like metal alkylthiophosphates, in particular zinc
alkylthiophosphates, and more specifically zinc dialkyldithiophosphates or ZnDTP. The
preferred compounds are of formula Zn((SP(S)(OR)(OR)b wherein R and R·, either
15 identical or different, represent independently an alkyl group, preferentially an alkyl group
including from 1 to 18 carbon atoms.
The amine phosphates are also anti-wear additives which may be used in the lubricant
composition according to the invention. However, the phosphorus brought by these
additives may act as a poison of catalytic systems of automobiles since these additives
20 are ash generators. It is possible to minimize these effects by partly substituting the
amine phosphates with additives not providing any phosphorus, such as for example,
polysulfides, notably sulfur-containing olefins.
Advantageously, the lubricant composition according to the invention may comprise from
0.01 to 6% by mass, preferentially from 0.05 to 4% by mass, more preferentially from 0.1
25 to 2% by mass based on the total mass of lubricant composition, of anti-wear additives
and extreme pressure additives.
Advantageously, the ·lubricant composition according lo the invention may comprise at
least one friction modifier additive. The friction modifier additive may be selected from
among a compound providing metal elements and a compound free of ashes. Among the
30 compounds providing metal elements, mention may be made of complexes of transition
metals such as Mo, Sb, Sn, Fe, Cu, Zn for which the ligands may be hydrocarbon
compounds comprising oxygen, nitrogen, sulfur or phosphorus atoms. The friction
modifier additives free of ashes are generally of organic origin and may be selected from
among fatty acid monoesters and from polyols, alkoxylated amines, alkoxylated fatty
35 a mines, fatty epoxides, borate fatty epoxides; fatty amines or esters of fatty acid glycerol.
14
According to the invention, the fatty compounds comprise at least one hydrocarbon group
comprising from 10 to 24 carbon atoms.
Advantageously, the lubricant composition according to the invention may comprise from
0.01 to 2% by mass or from 0.01 to 5% by mass, preferentially from 0.1 to 1.5% by mass
5 or from 0.1 to 2% by mass based on the total mass of the lubricant composition, of a
friction modifier additive.
Advantageously, the lubricant composition according to the invention may comprise at
least one antioxidant additive.
10 The antioxidant additive may generally delay the degradation of the lubricant composition
being used_ This degradation may notably be expressed by the formation of deposits, by
the presence of sludges or by an increase in the viscosity of the lubricant composition_
The antioxidant additives notably act as radical inhibitors or hydroperoxide destructive
inhibitors. From among the currently used antioxidant additives, mention may be made of
15 the antioxidant additives of the phenolic type, of the antioxidant additives of the aminated
type, of the phosphorus-sulfur-containing antioxidant additives. Certain of these
antioxidant additives, for example the phosphorus-sulfur-containing antioxidant additives
may be generators of ashes. The antioxidant phenolic additives may be free of ashes or
else be in the form of metal salts either neutral or basic_ The antioxidant additives may
20 notably be selected from among sterically hindered phenols, sterically hindered phenol
esters and sterically hindered phenols comprising a thioether bridge, diphenylamines,
diphenylamines substituted with at least one C1-C12 alkyl group, N,N'-dialkyl-aryl-diamines
and mixtures thereof_
Preferably according to the invention, the sterically hindered phenols are selected from
25 among the compounds comprising a phenol group for which at least one carbon in the
neighborhood of the carbon bearing the alcohol function is substituted with at least one
C1- C10 alkyl group, preferably a C1-C6 alkyl group, preferably a C4 alkyl group, preferably
by the ter-butyl group.
The aminated compounds are another class of antioxidant additives which may be used,
30 optionally in combination with phenolic antioxidant additives. Examples of aminated
compounds are aromatic amines, for example aromatic amines of formula NR'RbR'
wherein Ra represents an aliphatic group or an aromatic group, optionally substituted, Rb
represents an aromatic group, optionally substituted, R' represents a hydrogen atom, an
alkyl group, an aryl group or a group of formula RdS(O)zRe wherein Rd represents an
35 alkylene group or an alkenylene group, R' represents an alkyl group, an alkenyl group or
an aryl group and z represents 0, 1 or 2.
15
Sulfur-containing phenol alkyls or their alkaline metal and earth-alkaline metal salts may
also be used as antioxidant additives.
Another class of antioxidant additives is that of copper-containing compounds, for
examples copper thio- or dithio-phosphates, copper salts and of carboxylic acids,
5 dithiocarbamates, sulphonates, phenates, copper acetylacetonates. The copper salts I
and II, salts of succinic acid or anhydride may also be used.
The lubricant composition according to the invention may contain any types of antioxidant
additives known to one skilled in the art.
Advantageously, the lubricant composition comprises at least one antioxidant additive free
10 of ashes.
Also advantageously, the lubricant composition according to the invention comprises from
0.1 to 2% by weight based on the total mass of the composition, of at least one
antioxidant additive.
15 The lubricant composition according to the invention may also comprise at least one
detergent additive.
Detergent additives generally give the possibility of reducing the formation of deposits at
the surface of metal parts by dissolving secondary oxidation and combustion products.
The detergent additives which may be used in the lubricant composition according to the
20 invention are generally known to one skilled in the art. The detergent additives may be
anionic compounds comprising a long lipophilic hydrocarbon chain and a hydrophilic
head. The associated cation may be a metal cation of an alkaline or earth-alkaline metal.
The detergent additives are preferentially selected from among salts of alkaline metals or
of earth-alkaline metals of carboxylic acids, sulfonates, salicylates, naphthenates, as well
25 as salts of phenates. The alkaline and earth-alkaline metals are preferentially calcium,
magnesium, sodium or barium.
These metal salts geoorelly·comprise the metal in a stoichiometric amount or else in an
excess amount, therefore in an amount greater than the stoichiometric amount. These
are then overbased detergent additives; the excess metal providing the overbased nature
30 to the detergent additive is then generally in the form of a metal salt insoluble in oil, for
example a carbonate, a hydroxide, an oxalate, an acetate, a glutamate, preferentially a
carbonate.
Advantageously, the lubricant composition according to the invention may comprise from
0.5 to 8% or from 2 to 4% by weight of a detergent additive based on the total mass of the
35 lubricant composition.
16
Also advantageously, the lubricant composition according to the invention may also
comprise at least one pour point lowering additive.
By slowing down the formation of paraffin crystals, the pour point lowering additives
generally improve the cold behavior of the lubricant composition according to the
5 invention.
As an example of
polymethacrylates,
pour point lowering
polyacrylates,
polyalkylnaphthalenes, alkyl polystyrenes.
additives, mention may
polyarylamides,
be made of alkyl
polyalkylphenols,
10 Advantageously, the lubricant composition according to the invention may also comprise a
dispersant agent.
The dispersant agent may be selected from among Mannich bases, succinimides and
derivatives thereof.
Also advantageously, the lubricant composition according to the invention may comprise
15 from 0.2 to 10% by mass of a dispersant agent based on the total mass of the lubricant
composition.
Advantageously, the lubricant composition may also comprise at least one additional
polymer improving the viscosity index. As examples of an additional polymer improving
20 the viscosity index, mention may be made of polymeric esters, homopolymers or
copolymers, either hydrogenated or not, hydrogenated, of styrene, of butadiene and of
isoprene, polymethacrylates (PMA). Also advantageously, the lubricant composition
according to the invention may comprise from 1 to 15% by mass based on the total mass
of the lubricant polymeric composition improving the viscosity index.
25
In addition to a lubricant composition, the invention also relates to the use of this lubricant
composition. In -particCJiar; the invention relates to the use of a lubricant composition
according to the invention for the lubrication of a vehicle engine, in particular 14 for the
lubrication of an engine of a hybrid vehicle.
30 Preferably, the use of a lubricant composition according to the invention gives the
possibility of improving the lubrication of a vehicle engine. In a particularly preferred way,
the use of a lubricant composition according to the invention gives the possibility of
improving the lubrication of a vehicle engine during an urban cycle defined according to
the European cycle NEDC or during an urban cycle defined according to the European
35 cycle WL TP or further during a cold cycle defined according to the European cycle ECE.
17
The invention also relates to the use of a lubricant composition according to the invention
for improving the Fuel Eco (FE) of a lubricant.
The invention also relates to the use of a lubricant composition according to the invention
for reducing the fuel consumption of an engine, in particular of a vehicle engine, notably of
5 an engine of a hybrid vehicle.
10
According to the invention, the particular, advantageous or preferred features of the
lubricant composition according to the invention, give the possibility of defining the uses
according to the invention which are also particular, advantageous or preferred.
The different aspects of the invention may be illustrated by the following examples.
Example 1: preparation of lubricant compositions according to the invention
The different components of the lubricant compositions according to the invention are
15 mixed depending on the nature and on the amounts of products shown in table 1.
Lubricant compositions
according to the invention (% by
weight)
CL1 CL2 CL3 CL4
PAO- (Durasyn 164 lneos) 64.2 44.2 24.2 44.2
Oil of Group V - Monoester (Priolube 1414
20 40 60 0
Croda)
Oil of Group V - PAG of formula (82) with R3
-
0 0 0 40
C12H25, m = 2.45 and n = 1.97
Comb polymer - Comb polymethacrylate
6.2 6.2 6.2 6.2
(Viscoplex 3-200 Evonik)
Packet of additives -Ca sulfonates, anti-oxidant
agents of the alkylaled and hindered phenol
8.6 8.6 8.6 8.6
diphenylamine type, ZnDTP secondary,
dispersant of the bisuccinimide type
Anti-friction agent MoDTC (Sakuralube 525
1.0 1.0 1.0 1.0
Adeka)
Table 1
The characteristics of these lubricant compositions according to the invention are shown
in table 2.
18
Lubricant composition
CL1 CL2 CL3 CL4
SAEJ300 Grade OW12 OW12 OW12 OW16
calculated KV 130 (mm2 .s.1
) 4.62 4.32 4.63 4.79
KV100 -ISO 3104 (mm2.s 1
) 6.950 6.43 6.995 7.191
KV40 -1803104 (mm2 s-1
) 23.31 20.92 23.79 24.45
Vl-1802909 284 296 283 287
HTHS at 150 C- CEC L-036 (mPa.s) 2.24 2.17 2.15 2.83
CCS at -35 C- ASTM 05293 (mPa.s) I 839 I 1,415
Table 2
5 Example 2: preparation of comparative lubricant compositions
The different components of the comparative lubricant compositions according to the
nature and to the amounts of the products presented in table 3.
Comparative composition
(% by weight)
CC1 CC2
PAO- (Durasyn 164 lneos) 44,2 84,2
Group V Oil- Monoester (Priolube 1414 Croda) 40 0
Polymer- Linear Polymethacrylate (Viscoplex 6-054
6,2 0
Evonik)
Comb polymer - Comb Polymethacrylate (Viscoplex 3-
0 6,2
200 Evonik)
Packet of additves - Ca sulfonates, antioxidant agents
of the alkylated and hindered phenol and
8,6 8,6
diphenylamine type, secondary ZnDTP, dispersant of
the bisuccinimide type
Anti-friction agent MoDTC (Sakuralube 525 Adeka) 1,0 1,0
Table 3
10 The first comparative lubricant composition (CC1) does not comprise any comb
polymethacrylate but a linear polymethacrylate. The second comparative lubricant
5
19
composition (CC2) does not comprise any oil of group V but only the oil of group IV. The
characteristics of these comparative lubricant compositions are shown in table 4.
Comparative lubricant composition
CC1 CC2
SAEJ300 Grade OW12 OW16
calculated KV 130 (mm".s.1
) 3.84 4.03
KV100 -ISO 3104 (mm".s.1
) 5.970 6.358
KV40 -1803104 (mm".s.1
) 23.08 26.19
Vl-IS02909 225 210
HTHS at 150 C- CEC L-036 (mPa.s) 2.14 2.30
CCS at -35 C- ASTM 05293 (mPa.s) 968 2,268
Table4
Example 3: evaluation of the fuel saving performances of the lubricant compositions
according to the invention (CL2 and CL4) and of the comparative lubricant composition
(CC1l
During several tests according to the conditions described in the examples of WO
10 2012-025901, the fuel consumption during the lubrication by means of the lubricant
composition according to the invention is compared with the fuel consumption during the
use of a reference lubricant composition (base oil and packet of additives similar to the
packet of additives of the composition according to the invention - SAEJ300 grade 5W30).
The fuel consumption gains are evaluated by taking as a reference the fuel consumptions
15 resulting from the use of this reference lubricant composition. The obtained results are
shown in table 5.
Gain obtained by means of the lubricant
composition(%)
CL2 CL4 CC1
Full NEDC cycle 4.89 4.01 4.73
NEDC cycle cold ECE phase 12.84 10.34 11.11
NEDC cycle mixed urban cycle phase 7.48 5.58 6.03
Table 5
It is seen that the lubricant compositions CL2 and CL4 according to the invention give the
20 possibility of obtaining very significant fuel consumption gains. Thus, the lubricant
composition according to the invention CL2 allows gains larger than those obtained with
20
the comparative lubricant composition CC1 which does not comprise any comb
polymethacrylate. Moreover, the lubricant composition according to the invention CL4
comprises an oil of group V of the PAG type also gives the possibility of significant gains.
More particularly it is seen that these lubricant compositions according to the invention
5 give the possibility of highly significant fuel savings gains on the engine cycle at a low
temperature and at a low engine speed, which demonstrates the benefit of these lubricant
compositions according to the invention for obtaining even more significant fuel savings
under urban conditions.
10 Example 4: evaluation of the performances of the traction coefficient of the lubricant
compositions according to the invention (CL 1, CL2 and CL3) and of a comparative
lubricant composition (CC2)
15
The traction coefficient of the lubricant compositions is evaluated and the obtained results
are shown in table 6.
Lubricant composition
CL1 CL2 CL3 CC2
traction coefficient (MTM: T - 40 C, Ve- 1 m.- ,
0.019 0.018 0.016 0.023
SRR = 20% of load = 25 N)
Table 6
The lubricant compositions according to the invention therefore have very good traction
coefficients. These results confirm that the lubricant compositions according to the
invention give the possibility of reducing the friction coefficient and therefore to improve
20 the fuel savings gain as compared with a comparative lubricant composition comprising a
PAO and a comb polymer according to the invention but not comprising any oil of group V
according to the invention, and this with different oil contents of group V.
Example 5: evaluation of the engine cleanliness performances of the lubricant
25 compositions according to the invention (CL 1, CL2, CL3 and CL4) and of a comparative
lubricant composition (CC2)
The engine cleanliness properties are evaluated by the TEOST MHT test according to the
standard ASTM 07097 and the obtained results are shown in table 7 and expressed in
milligrams. The maximum acceptable value, notably for most automobile manufacturers,
30 is equal to 35 mg according to the ILSAC classification for an oil of grade OWxx.
Lubricant composition
21
CL 1 CL2 CL3 CL4 CC2
Deposit on the Teas! MHT rod -
12.2 11.9 22.7 10.7 7.6
ASTM 07097 (mg)
Table 7
The lubricant compositions according to the invention therefore give the possibility of
retaining good engine cleanliness, or even to improve the engine cleanliness and to be
5 compliant with the limits set by the automobile industry. It should be noted that these
good results in engine cleanliness are obtained with different contents of oil of group V
according to the invention.

Claims
1. A lubricant composition of a grade according to the SAEJ300 classification defined by
5 the formula (I)
wherein
• X represents 0 or 5;
(X) W (Y)
(I}
10 • Y represents an integer ranging from 4 to 20; and
15
20
25
comprising
(a) at least one polyalphaolefinic oil (PAO) for which the cinematic viscosity measured
at 100 C according to the ASTM 0445 standard ranges from 1.5 to 8 mm2.s-1
;
(b) from 1 0 to 80% by weight of the composition of at least one oil of group V for
which the cinematic viscosity measured at 100 oc according to the ASTM 0445
standard ranges from 1.5 to 8 mm2.s-1
;
(c) at least one comb polymer for which the three pendant chains comprise at least 50
carbon atoms and selected from among the copolymers of at least one polyolefin
and of at least one poly(alkyl}methacrylate; the copolymers of at least one
polyolefin and of at least one poly(alkyl)acrylate.
2. The lubricant composition according to claim 1 of a grade according to the SAEJ300
classification selected from among OW4, OW8, OW12, OW16, OW20, 5W4, 5W8, 5W12,
5W16, 5W20.
3. The lubricant composition according to one of claims 1 or 2, for which the cinematic
viscosity measured at 40 oc according to the ASTM 0445 standard ranges from 12 to 30
mm2 s·1
, preferably from 14 to 25 mm2 s·1
.
30 4. The lubricant composition according to one of claims 1 to 3 for which the cinematic
viscosity of the PAO, measured at 100 oc according to the ASTM 0445 standard, ranges
from 1.5 to 6 mm2 .s·1 or from 2 to 8 mm2 .s·1 or further from 2 to 6 mm2.s·'-
5. The lubricant composition according to one of claims 1 to 4 for which the average
35 molecular mass by weight of the PAO is less than 500 Oa or ranges from 50 to 500 Oa or
ranges from 50 to 350 Oa or from 50 to 300 Oa.
23
6. The lubricant composition according to one of claims 1 to 5 comprising from 20 to 80%,
from 30 to 60% or from 35 to 45% by weight of the oil composition of group V.
5 7. The lubricant composition according to one of claims 1 to 6, for which the oil of group V
is selected from among a monoester, a polyalkylene-glycol (PAG).
8. The lubricant composition according to one of claims 1 to 7, for which the oil of group V
is selected from among
10 • a monoester of formula (81);
(81)
wherein
o R1 represents a linear or branched, saturated or unsaturated hydrocarbon
15 group, comprising from 14 to 24 carbon atoms;
20
o R2 represents a linear or branched, saturated or unsaturated hydrocarbon
group, comprising from 2 to 18 carbon atoms;
• a polyalkylene-glycol (PAG) of formula (82)
(82)
wherein
o R3 represents al.inear or branched C1-C30-alkyl group;
o m and n represent independently an average number ranging from 1 to 5.
25 9. The lubricant composition according to one ol claims 1 to 8, for which the comb
polymer lor which the pendant chains are obtained by polymerization or by
copolymerization ol olefins, preferably of olefins comprising from 8 to 17 carbon atoms
and selected from among styrenes, substituted styrenes, butadiene added in 1 ,4, the
butadiene added in 1 ,2, the compounds of formula (C1)
(C1)
wherein a' and a2 represent independently a hydrogen atom or a C1-C18-alkyl group.
5 10. The lubricant composition according to one of claims 1 to 9, for which the comb
polymer is prepared by copolymerization
10
15
20
• of an olefinic monomer of formula (C2)
a4
a3-+--L~L2~0~
0
(C2)
wherein
o a3 represents a linear or branched C2-C8-alkyl group; a C3-C8-cycloalkyl
group; a C6-C10-aryl group;
o a• represents a hydrogen atom or a methyl group;
o L 1 represents a residue of 1 ,4 addition of butadiene; a residue of 1 ,4
addition of butadiene substituted with at least one C1-C6-alkyl group; a
residue of vinyl addition of styrene; a residue of vinyl addition of styrene
substituted with at least one C1-C6-alkyl group;
o L 2 represents a residue of vinyl addition of butadiene; a residue of vinyl
addition of butadiene substituted with a C1-C6-alkyl group; a residue of vinyl
addition of styrene; a residue of vinyl addition of styrene substituted with at
least one C1-C6-alkyl group;
o k andj represent independently 0 or an integer ranging from 1 to 3,000 and
the sum (k + j) is equal to an integer ranging from 7 to 3,000, preferably
ranging from 10 to 3,000; and
25 • of an alkyl-acrylic ester monomer or alkyl-methacrylic ester of formula (C3)
as
)yo"d
0
(C3)
wherein
25
o Q5 represents a hydrogen atom or a methyl group ;
o Q 6 represents a linear or branched C1-C26-alkyl group.
11. The lubricant composition according to one of claims 1 to 10 for which the comb
5 polymer is prepared by copolymerization
10
15
20
• of an olefinic monomer of formula (C4)
•
0~
0
(C4)
wherein
o Q 7 represents a C1-C6-alkyl group; a C6-aryl group;
o Q8 represents a hydrogen atom or a methyl group;
o Q9
, Q10 and Q11 represent independently a hydrogen atom or a C1-C18-alkyl
group;
o x, y and z represent independently 0 or an integer ranging from 1 to 3,000
and the sum (x + y + z) is equal to an integer ranging from 7 to 3,000,
preferably ranging from 10 to 3,000; and
of a alkyl-acrylic ester monomer or methacrylic- alkyl ester of formula (C3)
wherein
a'
~o,06
0
(C3)
o Q5 represents a hydrogen atom or a methyl group;
o Q6 represents a linear or branched C1-C26-alkyl group.
12. The lubricant composition according to one of claims 1 to 11 for which the weight ratio
25 (a/b) between the polyalphaolefinic oil (PAO) (a) and the oil of group V (b) ranges from 0.1
to 4, preferably from 0.3 to 3.6.
13. The lubricant composition according to one of claims 1 to 12, for which the VI is
greater than 220, preferably greater than 250, or even greater than 270 or 300.
26
14. The use of a lubricant composition according to one of claims 1 to 13, for the
lubrication of a vehicle engine or for improving the lubrication of a vehicle engine during
an urban cycle according to the European cycle NEDC.
5 15. The use of a lubricant composition according to one of claims 1 to 13, for the
lubrication of a vehicle engine or for improving the lubrication of a vehicle engine during
an urban cycle according to the European cycle WL TP.
16. The use of a lubricant composition according to one of claims'1 to 13, for the
1 0 lubrication of a vehicle engine or for improving the lubrication of a vehicle engine during a
cold cycle according to the European cycle ECE.
15
20
17. The use according to one of claims 14 to 16 for lubricating an engine of a hybrid
vehicle.
18. The use of a lubricant composition according to one of claims 1 to 17 for improving the
Fuel Eco (FE) of a lubricant or for reducing the fuel consumption of an engine, in particular
of a vehicle engine, notably of an engine of a hybrid vehicle.