LUBRICATING COMPOSITIONS FOR MOTOR VEHICLES

Abstract

Disclosed are lubricating compositions and base oils for motor vehicles, specifically for engines, gearboxes, or vehicle axle assemblies. The lubricating composition contains an oil-soluble polymer that is a specific polyalkyl glycol or a specific polyalkylene glycol (PAG). Also described is use of the lubricating composition for reducing fuel consumption in a vehicle provided with an engine, an axle assembly, or a gearbox that are lubricated using the lubricating composition or the specific PAG.

Claims

1-15. (canceled)

16. A lubricating composition comprising at least one oil of formula (I) ##STR00008## wherein R represents a linear or branched C.sub.1-C.sub.30 alkyl group; m and n represent independently an average number ranging from 1 to 5.

17. The lubricating composition according to claim 16 wherein R represents a group selected from among a linear C.sub.8 alkyl group; a branched C.sub.8 alkyl group; a linear C.sub.9 alkyl group; a branched C.sub.9 alkyl group; a linear C.sub.10 alkyl group; a branched C.sub.10 alkyl group; a linear C.sub.11 alkyl group; a branched C.sub.11 alkyl group; a linear C.sub.12 alkyl group; a branched C.sub.12 alkyl group; a linear C.sub.13 alkyl group; a branched C.sub.13 alkyl group; a linear C.sub.14 alkyl group; a branched C.sub.14 alkyl group; a linear C.sub.15 alkyl group; a branched C.sub.15 alkyl group.

18. The lubricating composition according to claim 16 wherein m is greater than or equal to n; or m represents an average number ranging from 2 to 4.5; or n represents an average number ranging from 1.5 to 4.

19. The lubricating composition according to claim 16 wherein m represents an average number ranging from 2.5 to 3.5; or n represents an average number ranging from 2 to 3.

20. The lubricating composition according to claim 16 wherein 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.

21. The lubricating composition according to claim 16 comprising at least one oil of formula (I) wherein (a) the kinematic viscosity at 100° C., measured according to the ASTM D445 standard, ranges from 2.5 to 4.5 mm.sup.2.Math.s.sup.−1; or for which (b) the viscosity index is greater than 160 or is comprised between 160 and 210; or for which (c) the pour point is less than −40° C.; or for which (d) the dynamic viscosity (CCS) at −35° C., measured according to the ASTM D5293 standard is less than 1,200 mPa.Math.s.

22. The lubricating composition according to claim 16, comprising at least one oil of formula (I) wherein (a) the kinematic viscosity at 100° C., measured according to the ASTM D445 standard, ranges from 2.5 to 4.5 mm.sup.2.Math.s .sup.−1; (b) the viscosity index is greater than 160 or is comprised between 160 and 210; (c) the pour point is less than −40° C.; (d) the dynamic viscosity (CCS) at −35° C., measured according to the ASTM D5293 standard is less than 1,200 mPa.Math.s.

23. The lubricating composition according to claim 16, comprising at least one oil of formula (I) wherein m represents an average number equal to 2.5 and n represents an average number equal to 2 and wherein (a) the kinematic viscosity at 100° C., measured according to the ASTM D445 standard, ranges from 2.5 to 3.5 mm.sup.2.Math.s.sup.−1; (b) the viscosity index is comprised between 160 and 180; (c) the pour point is less than −40° C.; (d) the dynamic viscosity (CCS) at −35° C., measured according to the ASTM D5293 standard is less than 500 mPa.Math.s.

24. The lubricating composition according to claim 16, comprising at least one oil of formula (I) wherein m represents an average number equal to 3.5 and n represents an average number equal to 2.8 and wherein (a) the kinematic viscosity at 100° C., measured according to the ASTM D445 standard, ranges from 3.5 to 4.5 mm.sup.2.Math.s.sup.−1; (b) the viscosity index is comprised between 180 and 210; (c) the pour point is less than −50° C.; (d) the dynamic viscosity (CCS) at −35° C., measured according to the ASTM D5293 standard is less than 1,200 mPa.Math.s.

25. The lubricating composition according to claim 16, comprising from 2 to 60% by weight of at least one oil of formula (I).

26. The lubricating composition according to claim 23, comprising from 5 to 40% by weight of at least one oil of formula (I).

27. The lubricating composition according to claim 24, comprising from 5 to 35% by weight of at least one oil of formula (I).

28. The lubricating composition according to claim 16, also comprising at least one other base oil selected from oils of group III, oils of group IV and oils of group V; or at least one additive; or at least one other base oil selected from oils of the group III, oils of group IV and oils of group V and at least one additive. A method for reducing the fuel consumption of an engine, or for reducing the fuel consumption of a vehicle equipped with a transmission, comprising providing and applying a suitable amount of at least one lubricating composition according to claim 16.

29. A method for reducing the traction coefficient of a transmission oil, comprising providing and applying at least one lubricating composition according to claim 16.

Description

EXAMPLE 1

Preparation of a PAG Oil of Formula (I) According to the Invention—Oil (1)

[0187] ##STR00004##

average values: m=3.53 and n=2.84

[0188] In an autoclave stainless steel reactor, dodecanol (2,647 g) is introduced as an initiator followed by a solution of 45% by mass of potassium hydroxide (28.2 g). The mixture is heated to 115° C. under a nitrogen atmosphere.

[0189] Next, the water is removed by flash evaporation (115° C., 3 MPa) up to a concentration of water of less than 0.1% by weight.

[0190] A mixture of 1,2-propylene oxide (2,910 g) and of 1,2-butylene oxide (2,910 g) are introduced into the reactor at a temperature of 130° C. and at a pressure of 490 kPa. The mixture is stirred and is left to react for 14 hours at 130° C.

[0191] The residual catalyst is separated by filtration through magnesium silicate at 50° C. in order to obtain the intermediate product (A) for which the kinematic viscosity measured at 40° C. according to the ASTM D445 standard is of 22.4 mm.sup.2.Math.s.sup.−1, the kinematic viscosity measured at 100° C. according to the ASTM 445 standard is 4.76 mm.sup.2.Math.s.sup.−1, the viscosity index is 137 and the pour point is −48° C.

[0192] In an autoclave reactor in stainless steel, the product (A) (8,266 g) is introduced. A solution of sodium methoxide at 25% by mass in methanol (3,060 g) is added and is stirred (180 revolutions per minute), at 120° C. for 12 hours, at a reduced pressure (less than 1 kPa) with a nitrogen flow (200 mL per minute).

[0193] Methyl chloride (751 g) is added at 80° C. and under pressure (260 kPa).

[0194] The mixture is stirred and is left to react for 1.5 hours at 80° C.

[0195] Next, flash evaporation is carried out (10 mins, 80° C., under reduced pressure) for separating dimethyl ether and methyl chloride not having reacted.

[0196] Water (2,555 g) is added and then is stirred for 40 minutes at 80° C. for washing the sodium chloride from the mixture. Stirring is stopped and the mixture is left at rest for 1 hour at 80° C.

[0197] The saline aqueous phase is separated by decantation (3,283 g), magnesium silicate (50 g) is added to the remaining mixture and flash evaporation is carried out (1 hour, 100° C., at a pressure of less than 1 kPa) under a nitrogen flow (200 mL per minute) and with stirring (180 revolutions per minute) in order to separate the residual water.

[0198] The mixture is left to cool at 60° C. and then is filtered on magnesium silicate at 50° C. for separating the oil (1) (8,359 g). The yield of the methylation step is of 98.6% by mass.

[0199] For this oil (1), the kinematic viscosity measured at 40° C. according to the ASTM D445 standard is 14.4 mm.sup.2.Math.s.sup.−1, the kinematic viscosity measured at 100° C. according to the ASTM D445 standard is 3.98 mm.sup.2.Math.s.sup.−1 and the pour point measured according to the ISO 3016 standard is −54° C.

[0200] The viscosity index of this oil is 194 and its dynamic viscosity (CCS) at −35° C., measured according to the ASTM D5293 standard is 1,120 mPa.Math.s.

EXAMPLE 2

Preparation of a PAG Oil of Formula (I) According to the Invention—Oil (2)

[0201] ##STR00005##

average values: m=2.45 and n=1.97

[0202] In an autoclave stainless reactor, dodecanol (2,369 g) is introduced as an initiator and then a solution of 45% by mass of potassium hydroxide (20.02 g). The mixture is heated to 115° C. under a nitrogen atmosphere. Flash evaporation is carried out (115° C. and 3 MPa) of the mixture for separating the water. The water concentration of the mixture is lowered to less than 0.1% by mass.

[0203] A mixture of 1,2-propylene oxide (1,808.5 g) and of 1,2-butylene oxide (1,808.5 g) are introduced into the reactor at a temperature of 130° C. and at a pressure of 490 kPa. The mixture is stirred and left to react for 14 hours at 130° C.

[0204] The residual catalyst is separated by filtration through magnesium silicate at 50° C. in order to obtain the intermediate product (B) for which the kinematic viscosity measured at 40° C. according to the ASTM D445 standard is 16.1 mm.sup.2.Math.s.sup.−1, the kinematic viscosity measured at 100° C. according to the ASTM D445 standard is 3.7 mm.sup.2.Math.s.sup.−1 and the pour point is −39° C.

[0205] In an autoclave stainless steel reactor, some product (B) (5,797 g) is introduced. A solution of sodium methoxide at 25% by mass in methanol (2,765 g) is added and is stirred (180 revolutions per minute), at 120° C. for 12 hours, at a reduced pressure (less than 1 kPa) with a nitrogen flow (200 mL per minute).

[0206] A portion of the mixture (3,825 g) of the reactor is emptied.

[0207] Next, in the other portion of the mixture (2,264 g) having remained in the reactor, methyl chloride (252 g) at 80° C. and under pressure (260 kPa) is added.

[0208] The mixture is stirred and is left to act for 1.5 hours at 80° C.

[0209] Next, flash evaporation is carried out (10 mins, 80° C., under reduced pressure) for separating dimethyl ether and the unreacted methyl chloride.

[0210] Water (796 g) is added and then stirred for 40 minutes at 80° C. for washing the sodium chloride of the mixture. The stirring is stopped and the mixture is left at rest for 1 hour at 80° C.

[0211] The saline aqueous phase (961 g) is separated by decantation, magnesium silicate (50 g) is added to the remaining mixture and flash evaporation is carried out (1 hour, 100° C., at a pressure of less than 1 kPa) under a flow of nitrogen (200 mL per minute) and with stirring (180 revolutions per minute).

[0212] The mixture is left to cool at 60° C. and then it is filtered on magnesium silicate at 50° C. for separating the oil (2) (2,218 g). The yield of the methylation step is 93.7% by mass.

[0213] For this oil (2), the kinematic viscosity measured at 40° C. according to the ASTM D445 standard is 9.827 mm.sup.2.Math.s.sup.−1,

[0214] the kinematic viscosity measured at 100° C. according to the ASTM D445 standard is 2.97 mm.sup.2.Math.s.sup.−1 and the pour point measured according to the ISO 3016 standard is −48° C.

[0215] The viscosity index of this oil is 172 and its dynamic viscosity (CCS) at −35° C. measured according to the ASTM D5293 standard is 450 mPa.Math.s.

COMPARATIVE EXAMPLE 3

Preparation of a Known PAG Oil—Comparative Oil (1)

[0216] ##STR00006##

average values: m=1.76 and n=1.42

[0217] In an autoclave stainless steel reactor, dodecanol (4,364 g) is introduced as an initiator followed by a solution of 45% by mass of potassium hydroxide (39.68 g). The mixture is heated to 115° C. under a nitrogen atmosphere.

[0218] Flash evaporation is carried out (115° C. and 3 MPa) of the mixture for separating the water. The water concentration of the mixture is lowered to 0.1% by mass.

[0219] 1,2-propylene oxide (2,276 g) and 1,2-butylene oxide (2,276 g) are introduced into the reactor at a temperature of 130° C. and at a pressure of 370 kPa. The mixture is stirred and left to act for 12 hours at 130° C.

[0220] The residual catalyst is separated by filtration through magnesium silicate at 50° C. in order to obtain the comparative oil (1) for which the kinematic viscosity measured at 40° C. according to the ASTM D445 standard is 12.2 mm.sup.2.Math.s.sup.−1, the kinematic viscosity measured at 100° C. according to the ASTM D445 standard is 3.0 mm.sup.2.Math.s.sup.−1 and the pour point is −29° C.

[0221] The viscosity index of this oil is 60 and its dynamic viscosity (CCS) at −35° C., measured according to the ASTM D5293 standard is 4,090 mPa.Math.s.

COMPARATIVE EXAMPLE 4

Preparation of a Known PAG Oil—Comparative Oil (2)

[0222] ##STR00007##

average values: m=2.79 and n=2.25

[0223] In an autoclave stainless steel reactor, dodecanol (3,141 g) is introduced as an initiator followed by a solution of 45% by mass of potassium hydroxide (38.4 g). The mixture is heated to 115° C. under a nitrogen atmosphere. Flash evaporation is carried out (115° C. and 3 MPa) of the mixture for separating the water. The water concentration of the mixture is lowered to 0.1% by mass.

[0224] A mixture of 1,2-propylene oxide (2,735.5 g) and of 1,2-butylene oxide (2,735.5 g) is introduced into the reactor at a temperature of 130° C. and at a pressure of 370 kPa. The mixture is stirred and left to react for 12 hours at 130° C.

[0225] The residual catalyst is separated by filtration through magnesium silicate at 50° C. in order to obtain the comparative oil (2) for which the kinematic viscosity measured at 40° C. according to the ASTM D445 standard is 18.0 mm.sup.2.Math.s.sup.−1, the kinematic viscosity measured at 100° C. according to the ASTM D445 standard is 4.0 mm.sup.2.Math.s.sup.−1 and the pour point is −41° C.

[0226] The viscosity index of this comparative oil (2) is 116 and its dynamic viscosity (CCS) at −35° C., measured according to the ASTM D5293 standard is 3,250 mPa.Math.s.

EXAMPLE 5

Preparation of Lubricating Compositions According to the Invention, of Comparative Lubricating Compositions and Evaluation of the Properties of These Compositions for the Lubrication of the Transmission of a Motor Vehicle

[0227] The lubricating compositions are prepared by mixing the oil (2) according to Example 2 and oils known with other base oils and with additives for preparing lubricating compositions according to the amounts (% by mass) of table 1.

TABLE-US-00002 TABLE 1 Composition Composition (1) according (2) according Comparative to the to the composition invention invention (1) base oil of group III (KV100/ 20.0 / 40.75 ASTM D445 = 3) base oil of group III (KV100/ 41.75 43.3 41.0 ASTM D445 = 4) oil (2) according to the 20.0 38.45 / invention additive improving the 6.0 6.0 6.0 viscosity index (polymethacrylate - PMA) additive improving viscosity 5.0 5.0 5.0 (polyethylene- polypropylene - PEPP) mixture of additives 7.0 7.0 7.0 (dispersant, detergent, antioxidant, extreme pressure agent, anti-wear, anti-foam agent) friction reducing additive 0.2 0.2 0.2 (organo-molybdenum) siliconed anti-foam additive 0.05 0.05 0.05

[0228] The characteristics of the prepared lubricating compositions are evaluated and the obtained results are shown in table 2.

TABLE-US-00003 TABLE 2 Composition Composition (1) according (2) according Comparative to the to the composition invention invention (1) viscosity index (ISO 2909) 197 205 185 traction coefficient (MTM: 0.045 0.043 0.053 T = 40 C., V.sub.e = 1 m/s, SRR = 20% load = 75 N) Energy yield deviation 0.20 0.21 0.06 relatively to a commercial oil resistance to oxidation (CEC 1517) (160 C.-192 h) KV 40 variation (%) −5.0 8.6 21.01 KV100 variation (%) 5.4 4.3 18.95 TAN variation (mg KOH/g) 0.23 0.22 1.3 amount of insoluble materials 0.0012 0.0032 0.004 (% by mass) Compatibility of elastomers (variation of hardness for RE1 fluorocarbon 2 1 3 RE2 polyacrylate ACM 1 −3 −2 HNBR1 −1 −3 1 75FKM595 8 9 ND 4 beads wear test (464 PSA 0.80 0.74 0.73 D55-1078/RENAULT D55 1994) diameter of wear (mm) 4 beads extreme pressure test 0.47 0.46 ND (4B6 ASTM D551136) diameter of wear before jamming (mm) last load before jamming 90 90 ND (kg) diameter of wear at the first 1.36 0.87 ND jamming (mm) first systematic jamming 120 120 ND load (kg) ND: no-availability

[0229] The energy yield is evaluated by comparison with a commercial oil for a gear box based on oils of group III (KV100=7.46 mm.sup.2.Math.s.sup.−1, KV40=33.97 mm.sup.2.Math.s.sup.−1, VI=196). The energy yield deviation between the evaluated compositions and this commercial oil is measured.

[0230] This test therefore gives the possibility of evaluating the energy yield and of quantifying the yield of the gear box used by comparing the output torque with the input torque.

[0231] The Fuel Eco property of the oils for gear boxes applied may thereby be evaluated.

[0232] During this test, a manual gear box with five gears was used. The oil temperatures are 20° C. and 50° C. They give the possibility of well differentiating the oils with their Fuel Eco properties, in particular under cold conditions (20° C.). The input torque is set to 30 Nm and then to 90 Nm. The input conditions are set to 1,000 rpm and then to 3,000 rpm. For each oil temperature and for each gear ratio, the conditions of use are shown in table B.

TABLE-US-00004 TABLE B Temperature of Torque at the input Conditions at the the oil (° C.) Gear ratio (Nm) input (rpm) 20 R2 30 1,000 90 3,000 30 1,000 90 3,000 R3 30 1,000 90 3,000 30 1,000 90 3,000 50 R4 30 1,000 90 3,000 30 1,000 90 3,000 R5 30 1,000 90 3,000 30 1,000 90 3,000

[0233] This test gives the possibility of simulating an NEDC European test and of determining CO.sub.2 emission and the fuel consumption of a gear box lubricated by means of a particular oil. The higher the yield value, better is the reduction in fuel consumption.

[0234] Thus, it is ascertained that as compared with a lubricating composition comprising two oils of group III of the state of the art, the lubricating compositions comprising the oil (2) according to the invention have improved properties.

[0235] The viscosity index is highly superior. The traction coefficient is lowered to at least 7%. The energy yield is also strongly improved and allows a gain of more than 3 times greater relatively to a composition based on a commercial oil based on oils of group III. These parameters therefore give the possibility of demonstrating the Fuel Eco gain of the composition according to the invention.

[0236] The lubricating compositions according to the invention also have a resistance to oxidation which is of the same level or even greater than that of the lubricating composition according to the state of the art. Their compatibility with the different elastomers may be used in transmission gaskets with which they are in contact, is also of the same level or even better than that of the lubricating composition of the state of the art.

[0237] Further, the compositions according to the invention allow good resistance to wear of the mechanical parts of a transmission for automobiles.

[0238] Finally it is ascertained that the improvements in the properties of the lubricating composition comprising 20% of oil (2) according to the invention are of the same order or even greater than those of the lubricating composition comprising 38.45% of oil (2) according to the invention.

EXAMPLE 6

Preparation of Lubricating Compositions According to the Invention, of Comparative Lubricating Compositions and Evaluations of the Properties of These Compositions for the Lubrication of a Vehicle Engine

[0239] The lubricating compositions are prepared by mixing oil (1) according to Example 1 and known oils with other base oils and with additives for preparing lubricating compositions according to the amounts (% by mass) of table 3.

TABLE-US-00005 TABLE 3 Composition Composition (3) according (4) according Comparative to the to the composition invention invention (2) base oil of group III (KV100/ 45.45 37.45 37.45 ASTM D445 = 4.16 mm.sup.2 .Math. s.sup.−1) base oil of group III: Neste 29.0 17.3 15.0 Nexbase 3050 base of group IV PAO / / 30.0 (KV100/ASTM D445 = 4.08 mm.sup.2 .Math. s.sup.−1) oil (1) according to the 8.0 27.7 / invention mixture of additives 10.9 10.9 10.9 (dispersants, detergent, DTPZn, amine antioxidant, phenolic antioxidant) additive improving the 3.2 3.2 3.2 viscosity index (hydrogenated polyisoprene-styrene - PISH) additive improving the 2.9 2.9 2.9 viscosity index (PMA) friction reducing additive 0.5 0.5 0.5 (MoDTC) anti-corrosion additive of the 0.05 0.05 0.05 amine type

[0240] The characteristics of the prepared lubricating compositions are evaluated and the obtained results are shown in table 4.

TABLE-US-00006 TABLE 4 Composition Composition (3) according (4) according Comparative to the to the composition invention invention (2) viscosity index (ISO 2909) 192 202 190 Noack volatility 10.3 9.5 10.4 (CEC L-40-93) (%) dynamic viscosity (CCS) 6,790 4,970 4,970 at −35° C. (ASTM D5293) (mPa .Math. s) resistance to oxidation (method GFC Lu-36-T-03) (170 C.-144 h) KV100 variation after 144 h −13.7 −10.6 −6.74 (ISO 3,405) (%) TAN variation after 144 h 3.1 4.8 7.1 (ASTM D664) (mg KOH/g) PAI variation after 144 h 55 173 102 (ASTM D7214) (A .Math. cm.sup.−1 .Math. mm.sup.−1) detergency - global score 1 6.0 5.4 5.5 (average) (CEC M-02-A-78) (merit/10) compatibility of elastomers hardness variation for RE1 fluorocarbon ND 0 0 RE2 polyacrylate ACM ND 1 4 RE3 silastic MCQ ND −22 −21 RE4 nitrile HNBR ND 0 1 ND: not available

[0241] As compared with a lubricating composition comprising two oils of group III and an oil of group IV of the state of the art, the lubricating compositions comprising the oil (1) according to the invention have improved properties.

[0242] The viscosity index is superior, or even highly superior, and the Noack volatility is improved. These parameters therefore give the possibility of demonstrating the <<Fuel-Eco>> gain of the composition according to the invention.

[0243] The lubricating compositions according to the invention also have a resistance to oxidation which is greater than that of the lubricating composition of the state of the art. The detergency of the lubricating compositions according to the invention is at the same level or even better than that of the lubricating composition of the state of the art.

[0244] The compatibility of the lubricating compositions according to the invention with the different elastomers may be used in the transmission gaskets with which they are in contact, is also on the same level or even better than that of the lubricating composition of the state of the art.

[0245] Finally it is ascertained that the improvements in the properties of the lubricating composition comprising 8% of oil (1) according to the invention are of the same order or even superior to those of the lubricating composition comprising 27.7% of oil (1) according to the invention.

EXAMPLE 7

Preparation of a Lubricating Compositions According to the Invention, of a Comparative Lubricating Composition and Evaluation of the Properties of These Compositions for the Lubrication of a Vehicle Engine

[0246] The lubricating compositions are prepared by mixing the oil (1) according to Example 1 and known oils with other base oils according to the amounts (% by mass) of table 5. A comparative lubricating composition (3) is also prepared from a comparative oil (2) according to the comparative example (3).

TABLE-US-00007 TABLE 5 Composition (5) according Comparative to the composition invention (3) base oil group III (KV100/ASTM 37.45 37.45 D445 = 4.16 mm.sup.2 .Math. s.sup.−1) base oil group III: Neste Nexbase 17.3 17.3 3050 oil (1) according to the invention 27.7 / Comparative oil (2) / 27.7 mixture of additives (dispersants, 10.9 10.9 detergent, DTPZn, amine antioxidant, phenolic antioxidant) additive improving the viscosity index 3.2 3.2 (PISH) additive improving the viscosity index 2.9 2.9 (PMA) friction reducing additive (MoDTC) 0.5 0.5 anti-corrosion additive of the amine 0.05 0.05 type

[0247] The characteristics of the prepared lubricating compositions are evaluated and the obtained results are shown in table 6.

TABLE-US-00008 TABLE 6 Composition (5) according to the Comparative invention composition (3) kinematic viscosity measured at 9.672 9.858 100 C. (ASTM D445) (mm.sup.2 .Math. s.sup.−1) viscosity index (ISO 2909) 202 193 Noack volatility (CEC L-40-93) (%) 9.5 12.3 dynamic viscosity (CCS) 4,970 6,250 at −35° C. (ASTM D5293) (mPa .Math. s)

[0248] As compared with a lubricating composition comprising two oils of group III and the comparative oil (2) of the state of the art, the lubricating composition comprising the oil (1) according to the invention has improved properties.

[0249] The kinematic viscosity measured at 100° C. is lower. The dynamic viscosity (CCS at −35° C.) is lower, which puts forward an improvement in the cold behavior of the composition according to the invention.

[0250] Further, the viscosity index is highly superior and the Noack volatility is strongly improved. These parameters therefore give the possibility of demonstrating the <<Fuel-Eco>> gain of the composition according to the invention.

EXAMPLE 8

Preparation of a Lubricating Composition According to the Invention, of a Comparative Lubricating Composition and Evaluation of the Properties of These Compositions for the Lubrication of a Vehicle Engine

[0251] The lubricating compositions are prepared by mixing the oil (1) according to Example 1 and known oils with other base oils and with additives for preparing lubricating compositions according to the amounts (% by mass) of table 7.

TABLE-US-00009 TABLE 7 Composition (6) according Comparative to the composition invention (4) base oil of group III (KV100/ASTM D445 = 48.7 48.7 4.38 mm.sup.2 .Math. s.sup.−1) base oil of group IV PAO (KV100/ASTM 20.0 20.0 D445 = 4.08 mm.sup.2 .Math. s.sup.−1) oil (1) according to the invention 10.0 / Comparative oil (2) / 10.0 mixture of additives (dispersants, detergent, 12.6 12.6 DTPZn, amine antioxidant, phenolic antioxidant) friction modifier additive (glycerol 0.5 0.5 monooleate) additive improving the pour point (PMA) 0.2 0.2 additive improving the viscosity index 8.0 8.0 (PISH)

[0252] The characteristics of the prepared lubricating compositions are evaluated and the obtained results are shown in table 8.

TABLE-US-00010 TABLE 8 Composition (6) according to the Comparative invention composition (4) viscosity index (ISO 2909) 195 192 kinematic viscosity measured at 100 C. 8.115 8.043 (ISO 31404) (mm.sup.2 .Math. s.sup.−1) dynamic viscosity (CCS) 4,480 4,950 at −35° C. (ASTM D5293) (mPa .Math. s) basicity number (total base number: 7.3 7.8 TBN) (ASTM D2896) resistance to oxidation (Daimler −9.1 −13.3 oxidation test FO - DIN 51453) (100 C.- 168 h) (%) resistance to oxidation (Daimler 18.8 14.2 oxidation test 5% B100 - DIN 51453) (100 C.-168 h) (%) Fuel Eco (W24 C250 CDI/engine - 3.84 2.62 OM651 vs MB RL002) (%)

[0253] As compared with a lubricating composition comprising an oil of group III, an oil of group IV and the comparative oil (2) of the state of the art, the lubricating composition comprising the oil (1) according to the invention has improved properties, and more particularly in “Fuel-Eco” gain.

[0254] The viscosity index is superior. The dynamic viscosity (CCS at −35° C.) is inferior.

[0255] The resistance to oxidation is improved.

EXAMPLE 9

Preparation of a Lubricating Composition According to the Invention, of a Comparative Lubricating Composition and Evaluation of the Properties of These Compositions for the Lubrication of the Transmission of a Motor Vehicle

[0256] The lubricating compositions are prepared by mixing the oil (2) according to Example 2 and known oils with other base oils and with additives for preparing lubricating compositions according to the amounts (% by mass) of table 9.

TABLE-US-00011 TABLE 9 Composition (7) according Comparative to the invention composition (5) base oil of group IV mPAO 55 55 (KV100/ASTM D445 = 3.5 mm.sup.2 .Math. s.sup.−1) oil (2) according to the 16.3 / invention comparative oil (1) / 16.3 additive improving the viscosity 6.0 6.0 index (PMA) additive improving the viscosity 14.0 14.0 index (PMA) Mixture of additives 8.7 8.7 (dispersants, detergent, antioxidant, extreme pressure agent, anti-wear agent, anti- foam agent, DTPZn)

[0257] The characteristics of the prepared lubricating compositions are evaluated and the obtained results are shown in table 10.

TABLE-US-00012 TABLE 10 Composition (7) according Comparative to the invention composition (5) viscosity index (ISO 2909) 212 200 traction coefficient (MTM: T = 0.036 0.041 40° C., V.sub.e = 1 m/s, SRR = 20% charge = 75 N)

[0258] As compared with a lubricating composition comprising an oil of group IV and the comparative oil (1) of the state of the art, the lubricating composition comprising the oil (2) according to the invention has improved properties.

[0259] The viscosity index is much superior and the traction coefficient is lowered by more than 12%. These parameters therefore give the possibility of demonstrating the Fuel-Eco gain of the composition according to the invention.