KR20090004532A - Lubricating oils having improved friction stability - Google Patents

Abstract

A lubricating oil composition is provided to improve rubbing stability achieving excellent stability by acylating a plurality of second amino radicals existing in the friction modifier in case that one or more second amino radicals exist in a polyamine chain. A lubricating oil composition includes a base lubricating oil, one or more oil soluble phosphorus-containing compounds and one or more polyalkylene polyamine friction modifiers. The hydrocarbyl substituent includes a carbon atom of 6 to 30.

Description

LUBRICATING OILS HAVING IMPROVED FRICTION STABILITY

The present invention is useful for providing excellent frictional stability to lubricating oils, especially power transmission fluids such as automatic transmission fluid (ATF), continuous variable transmission fluid (CVTF) and double clutch transmission fluid (DCTF), and furthermore, An additive composition useful for imparting good frictional properties to the fluid.

In addition, the present invention provides a method for imparting frictional stability to a lubricating oil comprising an additive composition; The use of additive compositions in lubricating oils to improve frictional stability; And other aspects as defined herein below.

Transmissions to which the present invention can be applied are transmissions comprising a wet clutch in a lubricated state used under high energy consumption conditions. Uses of this kind include clutches of automatic transmissions used to achieve ratio or speed changes; Wet start clutch of automatic, continuously variable or double clutch transmission; Or clutches for torque vectoring or mid-axis differential applications. These clutches are characterized by having a high differential speed between the two clutch members and consuming high energy when clutch "engagement" or "lock up".

Thus, a further aspect of the present invention relates to a power transmission device comprising a single-plate or multi-plate clutch element lubricated by the power transmission fluid of the present invention, wherein the clutch is in high energy conditions in use, i.e. At about 500 rpm (rpm) or more, in particular at speeds above 500 rpm.

A common goal for car manufacturers is to produce vehicles that are durable and reliable over the years of operation. A first aspect for increasing durability and reliability is to produce a vehicle that minimizes maintenance during service years. A second aspect is to have a vehicle continuously running over the "life". In the case of automatic transmissions, not only should the transmission not fail during the life of the vehicle, but also the transmission characteristics should not change significantly over the above period. Since the transmission characteristics of the automatic transmission are highly dependent on the friction characteristics of the ATF, the fluid needs to have a very stable friction performance according to the period, and thus the mileage. This aspect of ATF performance is known as friction stability. Many vehicle manufacturers are now moving to "fill-for-life" type automatic transmission fluids, and this trend further increases the need for frictional stability of the ATF, which translates into 15,000 to 50,000 miles of service. It will not change fluids anymore.

A common way to determine the friction durability of an ATF is to use a SAE # 2 friction tester. These devices use the clutch as a brake to simulate a high speed linkage of the clutch, thereby absorbing a certain amount of energy. The energy of the system is chosen to be equivalent to the energy absorbed by the clutch when one shift is achieved in the actual vehicle application. The instrument provides the test clutch and fluid with the required amount of energy using a specific interlock speed, typically 3600 rpm and calculated inertia. The clutch is lubricated by the volatilized fluid and makes each deceleration (ie, braking) of the system one cycle. Many cycles are run continuously to evaluate the frictional stability. As OEMs increasingly stress on frictional stability, the total number of cycles required to demonstrate satisfactory frictional stability has increased from hundreds of times in the 1980s to more than 10,000 in some current specifications. See, eg, Ford MERCON® V Automatic Transmission Fluid for Sevice specification.

There are two ways to evaluate the improvement of friction stability. The first is to maintain certain frictional properties over a long period of time (ie, over more cycles). The second is to make each friction variable less variable over the same number of cycles. The implications of these two methods are that the vehicle shift characteristics will be consistent over an extended number of miles.

Friction control in power transmission fluids such as ATF, CVTF or DCTF is primarily a function of friction modifier in the fluid. However, the thermal and oxidative stresses encountered by the fluids when using a transmission change the fluid properties by causing additional degradation. Oxidation or thermal breakdown of the friction modifiers often occurs first in the fluid as increasing static friction. The increase in static friction results in a sudden shift that may give the vehicle occupant a sudden pull or staggering when the shift is complete. The increase in static friction is a common failure mode of power transmission fluid. In some cases, however, oxidation of the friction modifiers can transform the friction modifiers into more active species. In these situations, static friction can actually be reduced during travel. The reduction of static friction, which is not usually a problem for the vehicle occupant, can lower the bearing capacity of the clutch in the transmission. If the bearing capacity is low, the clutch can slide under high loads, for example traction or rapid acceleration, so it is likely to overheat and eventually breaks down. Thus, the best power transmission fluids have a very stable static friction that is always well maintained in use.

Typically, there are two ways to improve the frictional stability of the power transmission fluid. One method is to increase the amount of friction modifier in the fluid. This provides the desired effect of improving the friction stability by providing a large reservoir of friction modifiers in the oil, but the undesirable incidentality of lowering the coefficient of friction of the fluid to an undesirable level, especially the static coefficient of friction, due to the increased amount of friction modifier. Affects. The second method is to use oxidation inhibitor additives together to improve the oxidation resistance of the fluid, in particular reducing the occurrence of polarized oxidation products, and then competing with friction modifiers on the friction surface. Thus, reducing fluid oxidation has the potential to improve friction control for a long time.

US Pat. Nos. 5,750,476 and 5,840,662 report that a combination of antioxidants, oil soluble phosphorus compounds and certain low potency friction modifiers can impart significant frictional durability to ATF. Such low titer friction modifiers are characterized in that once the saturation concentration of the friction modifier in the fluid is achieved, the measured friction level no longer decreases with increasing concentration. Since low titer friction modifier molecules are consumed through shear or oxidation, it is believed that there is always a concentration sufficient to replace them on the friction surface. In addition, oil soluble phosphorus-containing compounds must be present to prevent wear of the system.

However, such solutions require the use of high amounts of additives. There is a need for more efficient use of chemical feeds and more cost-effective solutions.

Similarly, the additional need for oxidation inhibitors results in more complex formulations and increases development and use costs.

Thus, the inventors have given a further improved thermal and oxidative stability to a class of friction modifiers, i.e. polyalkylene polyamine-based friction modifiers, by controlling the friction thereof by acylation of at least one secondary amino group present at its polyamine moiety. It has been found that it can be given without loss of ability. When at least one secondary amino group is present in the polyamine chain, good stability can be achieved by acylating a plurality, preferably all, of the secondary amino groups present in the friction modifier.

The friction modifiers exhibit improved physical properties compared to conventional solutions and provide a more cost-effective solution to the friction durability problems in oils, especially power transmission fluids.

A first aspect of the invention relates to a lubricating oil (particularly power transmission fluid) composition comprising an oil-soluble phosphorus compound and a polyalkylene polyamine-based friction modifier having at least one hydrocarbyl substituent comprising 6 to 30 carbon atoms. Wherein at least one secondary amino group in the polyamine chain of the friction modifier is acylated with the corresponding amide group.

In particular, the present invention relates to lubricating oil (particularly, power transmission fluid) compositions,

(a) a major amount of lubricant; And

(b) the reaction product of (i) an acylating agent R ₃ COX, wherein R ₃ is a hydrocarbyl group and X is a leaving group, and at least one compound selected from the group of compounds represented by formulas (I), (II) and (III) A friction modifier comprising a; And (ii) an oil-soluble phosphorus-containing compound, wherein the friction stability improving effective amount of the additive combination

It includes.

[Formula I]

[Formula II]

[Formula III]

(In the above formulas (I) to (III), R is a C ₆ to C ₃₀ alkyl or alkenyl group; R ₁ is a polyalkylene polyamine group represented by the following formula IV))

[Formula IV]

(In Formula IV, n and m are each independently an integer of 1 to 6; R ₂ is selected from an alkyl or aryl group or a heteroatom containing derivative thereof, or of the following Formulas V, VI and VII):

[Formula V]

[Formula VI]

[Formula VII]

In this embodiment, at least one, preferably each secondary nitrogen in formula (IV) of each of formulas (I), (II) and (III) is converted to an amide by reaction with an acylating agent so that To yield Formulas (VIII), (IX) and (X).

[Formula VIII]

[Formula IX]

[Formula X]

Wherein R, R ₁ , R ₂ , R ₃ and n are as defined above and p + q = m, where m is as defined above, provided that p≥1

In all of the above formulas, R ₃ is preferably one of C ₁ to C ₂₀ hydrocarbyl substituents, more preferably alkyl or aryl groups, or heteroatom-containing analogs thereof. Even more preferably, R ₃ is a C ₁ to C ₁₀ alkyl or aryl group, most preferably R ₃ is a C ₁ to C ₆ alkyl or aryl group, in particular methyl, ethyl, propyl or butyl.

Another aspect of the invention is a polyalkylene polyamine-based friction modifier as defined above (b) (i) itself; An additive composition comprising a friction modifier as defined above in combination with an oil-soluble phosphorus-containing compound; A method of imparting frictional stability to lubricating oil, comprising using an additive composition of the frictional stability improving effective amount as defined above; And the use of an additive composition as defined above in lubricants in an amount effective to improve frictional stability.

Further aspects and embodiments of the invention will be apparent from the detailed description below.

The present invention relates to a method of improving the frictional stability of lubricating oil without adversely lowering the coefficient of friction. The present invention includes the use of a combination of oil-soluble phosphorus and friction modifiers derived from certain polyalkylene polyamines in oils. The combination of these additives provides significant frictional stability to lubricating oils, in particular transmission fluids.

The advantages of the present invention are expected to be applicable to a variety of lubricating oils (e.g., crankcase engine oils, etc.) where friction modifiers are usefully employed, and particularly preferred compositions are power transmission fluids, in particular automatic transmission fluids (ATFs), continuously variable Transmission fluid (CVTF) and double clutch transmission fluid (DCTF). Other examples include gear oils, hydraulic oils, tractor fluids, universal tractor fluids, and the like, which are within the scope of the present invention but are less preferred types of power transmission fluids. These power transmission fluids can be formulated with a variety of additional performance additives and various base oils.

Of the present invention Polyalkylene Polyamine -Friction system Modifier

Preferred friction modifiers of the invention are prepared from succinimides comprising one or more hydrocarbyl substituents, wherein said or each hydrocarbyl substituent comprises 6 to 30 carbon atoms, preferably an alkenyl group or fully saturated Alkyl analogues); It is prepared from a carboxyl amide which has at least one alkenyl or alkyl chain comprising 6 to 30 carbon atoms and is at least one structure formed from the reaction of a corresponding alkenyl or alkyl carboxylic acid with a polyalkylene polyamine.

Most preferred types of friction modifiers are first produced by the reaction of alkyl or alkenyl succinic anhydrides, wherein the alkyl or alkenyl substituents are isomerized chains with at least one polyalkylene polyamine, preferably at least one polyethylene polyamine. In this preferred material, the isomerized chain is bonded to the α-carbon atom of the succinimide ring to form a bi-branched substituent bonded to the ring α-carbon atom via a tertiary carbon atom, e.g., with polyethylene polyamine The reacted alkenyl-substituted structure is represented by the following formula.

(Wherein x and y are each independently an integer whose sum is 1 to 25, and z is an integer of 1 to 10)

Methods of preparing such isomerized alkenyl succinic anhydrides are well known and are described, for example, in US Pat. No. 3,382,172. Typically, these materials are prepared by heating the alpha-olefins with an acidic catalyst to move the double bonds into their internal positions. The mixture of olefins (2-ene, 3-ene, etc.) is then heated with maleic anhydride. Typically, olefins of C ₆ (1-hexene) to C ₃₀ (1-triacontin) are used. Suitable formula (I) of isomerized alkenyl succinic anhydrides include iso-decylsuccinic anhydride (x + y = 5), iso-dodecylsuccinic anhydride (x + y = 7), iso-tetradecylsuccinic anhydride ( x + y = 9), iso-hexadecylsuccinic anhydride (x + y = 11), iso-octadecylsuccinic anhydride (x + y = 13) and iso-ecoxysuccinic anhydride (x + y = 15) do. Preferred materials are iso-hexadecylsuccinic anhydride and iso-octadecylsuccinic anhydride, which show particularly good performance.

The material produced by this process contains one double bond (alkenyl group) in the alkyl chain. Alkenyl substituted succinic anhydrides are readily converted to saturated alkyl analogs by hydrogenation.

The isomerized-alkenyl or -alkyl substituted succinic anhydride can then be reacted with a suitable amine to produce a friction modifier of the type of formula (I), which is then subjected to acylation with R ₃ COX to provide a friction modifier of the invention. (b) (i) is formed.

As an alternative to isomerized-alkenyl or -alkyl succinic anhydrides, carboxylic acids having one or more alkenyl or alkyl chains containing from 6 to 30 carbon atoms are reacted with a suitable amine type of formulas (II) and (III) To prepare a friction modifier. The acid is preferably an alkyl or alkenyl acid comprising 12 to 22 carbon atoms, in particular 16 to 20 carbon atoms. The friction modifier of the present invention is then formed by acylation with R ₃ COX.

Suitable amines for producing the friction modifiers of formulas (I), (II) and (III) are represented by the following formula (XI).

Formula XI

(Wherein n and m are each independently an integer of 1 to 6 and R ₂ is as defined above)

The amines of formula (XI) may be produced from the reaction of primary polyamines. Particularly suitable classes of such amines are the polyalkylene polyamines of the general formula (XII).

[Formula XII]

(Wherein a is an integer of 1 to 5, preferably 2 to 4; each n is independently an integer of 1 to 6, preferably 1 to 4)

Non-limiting examples of suitable polyamine compounds include diethylene triamine, triethylene tetraamine, tetraethylene pentamine and pentaethylene hexamine. Low cost mixtures of polyamines having 5 to 7 nitrogen atoms per molecule are available from Dow Chemical Co. as polyamine H, polyamine 400 and polyamine E-300.

Said polyamines may be reacted with the aforementioned succinic anhydrides substituted by alkenyl groups or their fully saturated alkyl analogs to form formula (I); It may be reacted with the alkenyl or alkyl carboxylic acid described above to form formula (II) or (III).

Preferred friction modifiers of the present invention are typically prepared by heating the aforementioned isomerized alkenyl succinic anhydride with the polyamine and removing the water formed. However, other manufacturing methods are also known and may be used. The ratio of primary amine groups to succinic anhydride groups is usually one to one. In the case of diamines or polyamines whose ends are terminated with primary amines, it may be desirable to react all of the amine terminators of the molecule with the substituted succinic anhydride to produce a substance of formula (XIII).

[Formula XIII]

Wherein R, a and n are as defined above

The acylating agent of the present invention is a substance capable of converting secondary amines into amides. The material is of formula R ₃ COX, wherein R ₃ is a hydrocarbyl group, X is a leaving group, and the leaving group is also linked to the R ₃ group of the acylating agent to form a ring structure.

R ₃ is preferably one of C ₁ to C ₂₀ hydrocarbyl substituents, preferably alkyl or aryl groups, or heteroatom-containing analogs thereof. More preferably, R ₃ is a C ₁ to C ₁₀ alkyl or aryl group, most preferably a C ₁ to C ₆ alkyl or aryl group. Most preferably alkyl, for example methyl, ethyl, propyl or butyl.

Preferred acylating agents for use are acetic anhydride, propionic anhydride, butyric anhydride, trifluoroacetic anhydride, acetyl chloride, propionyl chloride, butyryl bromide, butyrolactone, caprolactone, methyl acetate, ethyl acetate, butyl acetate , Butyl propionate and butyl butrate. Most preferred is acetic anhydride.

Preferred friction reducing agents of the present invention are those prepared by first reacting alkenyl succinic anhydride with polyamines (XI) and then with acetic anhydride. Most preferred products of the present invention are those prepared by reacting the isomerized-alkenyl succinic anhydride with polyamines (XII) followed by acetic anhydride.

Most preferred friction modifier (b) (i) of the present invention has the formula

It is suitably formed by the acetylation of the reaction product of diethylene triamine and the essential isomerized octadecenyl succinic anhydride. Such materials have been found to provide particularly good performance for the present invention. Both the friction modifier additive comprising the compound and the compound itself represent further embodiments of the present invention.

Although any effective amount of friction modifier can be used in various embodiments of the present invention, the throughput of the friction modifier is typically about 0.1 to about 10, preferably 0.5 to 7, most preferably 1.0 to 5.0 weight percent in the lubricant composition. .

Examples of the preparation of typical friction modifier materials of the present invention are described below. These examples are for illustrative purposes and the invention is not limited to the specific details set forth in the examples below.

Production Example

Example  A ( Isomerized Succinimide  Produce)

352 gm (1.00 mole) of iso-octadecenylsuccinic anhydride (ODSA, Dixie Chemical) in a 1 liter round bottom flask equipped with mechanical stirrer, nitrogen sweep, Dean Starke trap and condenser Co.)). The nitrogen sweep was started slowly and the material was heated to 130 ° C. while starting the stirrer. Immediately, 95 gm (0.50 mole) of commercial tetraethylene pentamine was added slowly to the hot water stirred iso-octadecenylsuccinic anhydride via an addition funnel. The temperature of the mixture was increased to 150 ° C. and maintained for 2 hours. During this heating period, 100 ml of water (theoretical yield of about 50%) was collected in the Dean Starke trap. The flask was cooled to give the product. Yield: 435 gm. Nitrogen%: 8.1.

Example  B ( Isomerized Succinimide  Produce)

The same procedure was followed as in Example A, except that the following amounts were used: 700 gm (2.0 moles) of iso-octadecenylsuccinic anhydride, and 103 gm (1.0 moles) of diethylenetriamine. The recovered water was 32 ml. Yield: 765 gm. Nitrogen%: 5.5.

Example  C (of the present invention Acylated Isomerized Succinimide  Produce)

765 gm (1.0 mole) of the product of Example B was placed in a 1 liter round bottom flask equipped with a mechanical stirrer, nitrogen sweep, Dean Starke trap and condenser. The nitrogen sweep was started slowly and the material was heated to 90 ° C. while starting the stirrer. Acetic anhydride, 102 gm (1.0 mole) was added dropwise via an addition funnel. When the addition was complete, the temperature was increased to 140 ° C. and maintained for 3 hours. Residual acetic acid was removed by distillation at 150 ° C. at 50 mmHg. Yield: 805 gm. Nitrogen%: 5.2.

Example  D (of the present invention Acylated Isomerized Succinimide  Produce)

The same procedure was followed as in Example C, except that the following amounts were used: 765 gm (1.0 mole) of the product of Example B, and 131 gm (1.15 mole) of caprolactone. The mixture was heated at 170 ° C. for 6 hours and then 2 ml of stannous octanoate was added. After addition of octanoate, the temperature was increased to 180 ° C. for an additional 4 hours. Yield: 895 gm. Nitrogen%: 4.7.

Example  E (of the present invention Acylated Isomerized Succinimide  Produce)

429 gm (0.50 mole) of Example A's product was placed in a 1 liter round bottom flask equipped with a mechanical stirrer, nitrogen sweep, Dean Starke trap and condenser. The nitrogen sweep was started slowly and the material was heated to 90 ° C. while starting the stirrer. Acetic anhydride, 61 gm (0.5 mole) was added dropwise via an addition funnel. When the addition was complete, the temperature was increased to 140 ° C. and maintained for 3 hours. Residual acetic acid was removed by distillation at 150 ° C. at 50 mmHg. Yield: 485 gm. Nitrogen%: 7.1.

Example  F ( Isostearic acid - TEPA of Acylated  Preparation of the product)

402 gm (1.37 moles) of iso-stearic acid was placed in a 1 liter round bottom flask equipped with a mechanical stirrer, nitrogen sweep, Dean Starke trap and condenser. The nitrogen sweep was started slowly and the material was heated to 100 ° C. while starting the stirrer. Tetraethylene pentamine (TEPA), 130 gm (0.69 moles) was added dropwise via an addition funnel over 1 hour. When the addition was complete, the temperature was increased to 160 ° C. for 6 hours, during which time 24 gm of water was recovered (98% of theory). The material was cooled to 100 ° C. and 71 gm (0.69 mole) of acetic anhydride was added dropwise through an addition funnel. When the addition was complete, the temperature was increased to 140 ° C. and maintained for 3 hours. Residual acetic acid was removed by distillation at 130 ° C. at 50 mmHg. Yield: 560 gm. Nitrogen%: 8.8.

Usability -Containing compounds

In its broadest aspect, oil soluble phosphorus-containing compounds useful in the present invention can vary widely and the type of species is not limited. The only limitation is that the material is useful, such that the phosphorus-containing compound in the lubrication system must be dispersed and transported to its active site. Examples of suitable phosphorus compounds include phosphites and thiophosphites (mono-alkyl, di-alkyl, tri-alkyl and partially hydrated analogs thereof); Phosphates and thiophosphates; Amines treated with inorganic phosphorus such as phosphorous acid, phosphoric acid or thio analogs thereof; Zinc dithiophosphate; Amine phosphate. Examples of particularly suitable phosphorus compounds include mono-n-butyl-hydrogen-acid-phosphite; Di-n-butyl-hydrogen phosphite; Triphenyl phosphite; Triphenyl thiophosphite; Tria-n-butylphosphate; 900MW polyisobutenyl succinic anhydride (PIBSA) polyamine dispersant post-treated with dimethyl octadecanyl phosphonate, H ₃ PO ₃ and H ₃ BO ₃ ; Zinc (di-2-ethylhexyldithiophosphate).

Preferred oil-soluble phosphorus compounds are esters of phosphoric acid and phosphorous acid. These materials include di-alkyl, tri-alkyl and tri-aryl phosphites and phosphates. Preferred oil-soluble phosphorus compounds are, for example, mixed thioalkyl phosphite esters prepared in US Pat. No. 5,314,633, which is incorporated herein by reference. Most preferred phosphorus compounds are thioalkyl phosphites, for example as illustrated by Example G below.

The phosphorus compounds of the present invention can be used in the oil in any effective amount. However, a typical effective concentration of the compound is to deliver about 5 to about 5000 ppm of phosphorus to the oil. Preferred concentration ranges are from about 10 to about 1000 ppm of phosphorus in the final oil and most preferred concentration range is from about 50 to about 500 ppm.

Example

Example  G

The alkyl phosphite mixture was prepared by putting 194 grams (1.0 mole) of dibutyl hydrogen phosphite into a round bottom four-neck flask equipped with a reflux condenser, a stirrer and a nitrogen aeration device. The flask was washed with nitrogen and sealed to start the stirrer. Dibutyl hydrogen phosphite was heated to 150 ° C. under vacuum (−90 kPa) and 190 grams (1 mol) of hydroxyethyl-n-octyl sulfide was added via dropwise funnel over about 1 hour. During the addition, approximately 35 ml of butanol was recovered in the cold trap. After the addition of hydroxyethyl-n-octyl sulfide was complete, heating continued for 1 hour, and no butanol was recovered. The reaction mixture was cooled down and the amounts of phosphorus and sulfur analyzed. The final product had a TAN of 115 and contained 8.4% phosphorus and 9.1% sulfur.

Other additives known in the art may also be added to the lubricating oil of the present invention or may be included in the additive composition of the present invention. These additives include dispersants, antiwear agents, corrosion inhibitors, detergents, extreme pressure agents and the like. These are typically described, for example, in "Lubricant Additives" by C.V. Smallheer and R. Kennedy Smith, 1967, pp. 1-11 and US Pat. No. 4,105,571.

Representative amounts of these additives in ATF are summarized in the table below.

additive % By weight (wide) % By weight (preferred) VI enhancer 1-12 1-4 Corrosion inhibitor 0.01-3 0.02-1 Dispersant 0.10-10 2-5 Antifoam 0.001-5 0.001-0.5 Detergent 0.01-6 0.01-3 Abrasion resistant 0.001-5 0.2-3 Pour point depressant 0.01-2 0.01-1.5 Seal swellant 0.1-8 0.5-5 lubricant Balance Balance

Suitable dispersants include long chain (ie more than 40 carbon atoms) substituted hydrocarbyl succinimides and hydrocarbyl succinimates, mixed chain ester / amides of long chain (ie more than 40 carbon atoms) hydrocarbyl-substituted succinic acids, Hydroxyesters of hydrocarbyl-substituted succinic acids, and Mannich condensation products of long chain (ie, more than 40 carbon atoms) hydrocarbyl-substituted phenols, formaldehyde and polyamines. Mixtures of the above dispersants may also be used.

Preferred dispersants are long chain alkenyl succinimides. These include acyclic hydrocarbyl substituted succinimides formed by various amines or amine derivatives as widely disclosed in the patent literature. Alkenyl succinimides treated with inorganic acids of phosphorus (or their anhydrides) and boronating agents are also compatible with elastomeric seals made of materials such as fluoro- and silicone-containing elastomers, It may be suitable for use in the composition. Polyisobutenyl succinic anhydrides, and polyisobutenyl succinimides formed from alkylene polyamines such as triethylene tetraamine or tetraethylene pentamine, wherein the polyisobutenyl substituents range from 500 to 5000 (preferably between 800 and Particularly derived from polyisobutene having a number average molecular weight of 2500). Dispersants may be post-treated with various reagents known to those skilled in the art (see, eg, US Pat. Nos. 3,254,025, 3,502,677 and 4,857,214).

The additive combinations of the present invention can be mixed with other necessary lubricant additives to form concentrates. Typically, the active ingredient (a.i.) level of the concentrate is 20 to 90% by weight, preferably 25 to 80% by weight, most preferably 35 to 75% by weight. The remainder of the concentrate is a diluent, which typically consists of a lubricant or a solvent.

Lubricants useful in the present invention are derived from natural lubricants, synthetic lubricants, and mixtures thereof. Generally, both the natural and synthetic lubricants will each have a kinematic viscosity in the range of about 1 to 100 mm 2 / s (cSt) at 100 ° C., but in typical applications about 2 to 8 mm 2 at 100 ° C. for each oil Requires a viscosity in the range of / s (cSt).

Natural lubricating oils include animal oils, vegetable oils (eg, castor oil and lard oil), petroleum, mineral oil, and oils derived from coal or shale. Preferred natural lubricants are mineral oils.

Suitable mineral oils include all conventional mineral oil basestocks. This includes naphthalene or paraffinic oils in chemical structure. The oil is purified in a conventional manner using other agents such as acids, alkalis and clays, for example aluminum chloride, or by solvents such as, for example, phenol, sulfur dioxide, furfural, dichlorodiethyl ether, and the like. Extraction oil produced by solvent extraction. They may be hydrotreated or hydrorefined, dewaxed by a cooling or catalytic dewaxing process, or hydrolyzed. Mineral oils may be produced from natural crude sources or may consist of isomerized wax materials or residues from other refining processes.

Typically, the mineral oil will have a dynamic viscosity in the range of 2.0 to 8.0 mm 2 / s (cSt) at 100 ° C. Preferred mineral oils have a dynamic viscosity in the range of 2 to 6 mm 2 / s (cSt) at 100 ° C., and most preferred mineral oils have a dynamic viscosity in the range of 3 to 5 mm 2 / s (cSt).

Synthetic lubricating oils are hydrocarbon oils and halo-substituted hydrocarbon oils such as oligomerized, polymerized, interpolymerized olefins [eg, polybutylene, polypropylene, propylene, isobutylene copolymers, chlorinated poly Lactenes, poly (1-hexene), poly (1-octene), poly (1-decene) and the like and mixtures thereof; Alkylbenzenes (eg dodecylbenzene, tetradecylbenzene, dinonyl-benzene, di (2-ethylhexyl) benzene, etc.); Polyphenyls [eg, biphenyls, terphenyls, alkylated polyphenyls, etc.]; And alkylated diphenyl ethers, alkylated diphenyl sulfides, as well as derivatives, analogs and homologs thereof, and the like. Preferred oils in these classes of synthetic oils are oligomers of α-olefins, in particular oligomers of 1-decene.

Synthetic lubricants also include alkylene oxide polymers, interpolymers, copolymers and derivatives thereof, wherein the hydroxyl end groups are modified by esterification, etherification and the like. Examples of these synthetic oil classes include polyoxyalkylene polymers prepared by polymerization of ethylene oxide or propylene oxide; Alkyl and aryl ethers of these polyoxyalkylene polymers (eg, methyl-polyisopropylene glycol ethers having an average molecular weight of 1000, diphenyl ethers of polypropylene glycols having a molecular weight of 1000-1500); And mono- and poly-carboxyl esters thereof (eg, acetic acid esters, mixed C ₃ -C ₈ fatty acid esters, and C ₁₂ oxoacid diesters of tetraethylene glycol).

Another suitable class of synthetic lubricants include various alcohols (eg, butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl alcohol, ethylene glycol, diethylene glycol monoether, propylene glycol, and the like). Having dicarboxylic acids (e.g., phthalic acid, succinic acid, alkyl succinic acid and alkenyl succinic acid, maleic acid, azelaic acid, suveric acid, sebacic acid, fumaric acid, adipic acid, linoleic acid dimer, malonic acid, alkylmalonic acid, alkenyl malonic acid Etc.). Specific examples of these esters include dibutyl adipate, di (2-ethylhexyl) sebacate, dioctyl phthalate, didecyl phthalate, diecosyl sebacate, 2-ethylhexyl diester of linoleic acid dimer, and 1 mole seba Complex esters formed by reacting succinic acid with 2 moles of tetraethylene glycol and 2 moles of 2-ethyl-hexanoic acid, and the like. Preferred types of oils in this class of synthetic oils are adipates of C ₄ to C ₁₂ alcohols.

Esters useful as synthetic lubricants are also C ₅ to C ₁₂ monocarboxylic acids, and polyols and polyol ethers such as neopentyl glycol, trimethylolpropane pentaerythritol, dipentaerythritol, tripentaeryth It includes those produced from lititol and the like.

Silicon-based oils (eg, polyalkyl-, polyaryl-, polyalkoxy-, or polyaryloxy-silicone oils and silicate oils) include another useful class of synthetic lubricants. These oils include tetra-ethyl silicate, tetraisopropyl silicate, tetra- (2-ethylhexyl) silicate, tetra- (4-methyl-2-ethylhexyl) silicate, tetra- (p-tert-butylphenyl) silicate, Hexa- (4-methyl-2-pentoxy) -disiloxane, poly (methyl) -siloxane, poly (methylphenyl) siloxane, and the like. Other synthetic lubricants include liquid esters of phosphorus-containing acids (eg, tricresyl phosphate, trioctyl phosphate, and diethyl ester of decylphosphonic acid), polymeric tetra-hydrofuran, poly-α-olefins, and the like.

Lubricants can be derived from refined oils, refined oils, or mixtures thereof. Unrefined oils are obtained directly from natural or synthetic sources (eg, coal, shale or tar sands bitumen) without further purification or treatment. Examples of unrefined oils include shale oils obtained directly from the retorting process, petroleum directly obtained from the distillation, or ester oils obtained directly from the esterification process, each of which is then used without further treatment. do. Refined oils are similar to unrefined oils, except that refined oils are treated in one or more purification steps to improve one or more physical properties. Suitable purification techniques include distillation, hydrotreating, dewaxing, solvent extraction, acid or base extraction, filtration and perfusion, all of which are known to those skilled in the art. Rerefined oils are obtained by treating the oils used in processes similar to those used to obtain the refined oils. Such re-refined oils are also known as recycled or reprocessed oils and are often further processed by techniques for removing waste additives and oil breakages.

Another class of suitable lubricating oils is basestocks resulting from oligomerization of natural gas feed stocks or isomerization of waxes. These basestocks can be referred to in a variety of ways, but are commonly known as Gas-to-Liquid (GTL) or Fischer-Tropsch basestocks.

Where the lubricating oil is a mixture of natural and synthetic lubricating oils (ie partial synthesis), the choice of partial synthetic oil components can vary widely, but particularly useful combinations are oligomers of mineral oil and poly-α-olefins (PAO), in particular 1-decene to be.

The following examples are provided as specific examples of the claims invention. However, it should be understood that the invention is not limited to the specific details disclosed in the examples. Unless otherwise specified, units are parts by weight and weight percent.

Test Example

A variant of the Ford MERCON® Friction Test (MERCON® Automatic Transmission Fluid Specification for Service, September 1, 1992, section 3.8) was chosen to demonstrate the friction durability of the fluids of the present invention. The pod test measures friction durability by using a low volume of fluid and high test energy per cycle. This high energy test fluid is repeatedly flown into small volumes for 10,000 cycles to assess the ability of the fluid to maintain constant frictional properties. The pod test method was modified as shown below.

Tests performed:

Friction material: Borg Warner 6100 (without grooves)

Test temperature: 115 ℃

Total test cycles: 10,000

Cycles Per Minute: 3

Total energy per cycle: 20,400 J

Piston Application Pressure: 275 kPa

Static Friction Measurement:

Speed: 4.37 rpm

Applied Pressure: 275 kPa

Static friction: measured after 2 seconds of rotation

Since the main role of the friction modifier of the present invention is to reduce static friction and to maintain that level for the life of the fluid, the product of the present invention is compared to the non-acylated materials in the SAE # 2 friction tester described above. The stability of the static friction coefficient (Mu-s or μ _s ) was compared.

Three test fluids were blended using the same base lubricant, dispersant, antioxidant and viscosity modifier. The test blend contained the most preferred oil soluble phosphorus source (Example G) and was prepared as disclosed in US Pat. No. 5,314,633. Into each fluid 3.0% by mass of friction modifier was added as follows.

Fluid A: containing the product of Example B

Fluid B: Contains the Product of Example C

Fluid C: containing the product of Example D

The composition of the test fluid and its test results are summarized in Table 1 below.

Test Formulations and Test Results ingredient Blend One 2 3 Boron-Added PIBSA / PAM Dispersant 3.60 3.60 3.60 PIBSA / PAM Dispersant Without Boron 1.50 1.50 1.50 Alkylated Diphenyl Amine Antioxidants 0.75 0.75 0.75 Sterically hindered phenolic antioxidants 0.25 0.25 0.25 Alkyl mercaptothiadiazole 0.09 0.09 0.09 Product of Example G 0.40 0.40 0.40 Product of Example A 0.30 0.30 0.30 Product of Example B 3.30 - - Product of Example C - 3.30 - Product of Example D - - 3.30 Thioalkyl ester 0.10 0.10 0.10 Long-chain fatty acids 0.10 0.10 0.10 Long chain fatty amide 0.10 0.10 0.10 Calcium Sulfate, 300 TBN 0.20 0.20 0.20 Sulfolane seal swelling agent 1.5 1.5 1.50 Polymethacrylate viscosity modifier 3.00 3.00 3.00 Group III base stock 84.81 84.81 84.81 gun 100.00 100.00 100.00 Static friction change 500 to 10,000 cycles  0.013  0.002  0.003

As can be seen from Table 1, the conventional friction modifier (fluid A) of Example B exhibits a decrease in static friction of 0.013 over a 500 to 10,000 cycle period. Fluids containing the products of the present invention, examples C and D, show lower static friction changes, a decrease of 0.002 for fluid B, and a decrease of 0.003 for fluid C.

Therefore, it is evident from the above test that the friction stability is improved due to the acylation of the alkylene amine-based friction modifier.

The principles, preferred embodiments and modes of operation of the present invention have been described above. However, the invention intended to be protected herein is not to be construed as limited to the specific forms disclosed, which are to be regarded as illustrative rather than restrictive. Those skilled in the art will be able to make various changes and modifications to the invention without departing from the spirit of the invention.

Claims (7)

At least one polyalkylene polyamine-based friction modifier comprising a base lubricant, at least one oil soluble phosphorus-containing compound, and at least one hydrocarbyl substituent, Wherein said or each hydrocarbyl substituent comprises 6 to 30 carbon atoms and at least one secondary amino group present in the polyamine chain of the friction modifier is acylated with a corresponding amide group. (a) a large amount of base lubricant; And (b) (i) acylating agent R ₃ COX, wherein R ₃ is a hydrocarbyl group and X is a leaving group, and one selected from the group of compounds represented by the following formulas (I), (II) and (III) At least one friction modifier comprising a reaction product of at least one compound; And (ii) one or more oil-soluble phosphorus-containing compounds A combination of additives of a friction stability improving effective amount comprising a Comprising a composition. [Formula I]

[Formula II]

[Formula III]

(In the above formulas (I) to (III), R is a C ₆ to C ₃₀ alkyl or alkenyl group; R ₁ is a polyalkylene polyamine group represented by the following formula IV)) [Formula IV]

(In Formula IV, n and m are each independently an integer of 1 to 6; R ₂ is selected from an alkyl or aryl group or a heteroatom containing derivative thereof, or of the following Formulas V, VI and VII): [Formula V]

[Formula VI]

[Formula VII]

The method of claim 2, Wherein the friction modifier (b) (i) comprises a reaction product represented by one or more of the following formulas (VIII), (IX) and (X). [Chemical City VIII]

[Formula IX]

[Formula X]

(Wherein R, R ₂ , R ₃ , n and m are as defined in claim 2 and p + q = m where p ≧ 1) The method of claim 1, Wherein said composition is a power transmission fluid. An additive composition comprising at least one hydrocarbyl substituent comprising 6 to 30 carbon atoms and comprising at least one secondary amino group present in the polyamine chain, together with the oil-soluble phosphorus-containing compound, a friction modifier acylated with a corresponding amide group. . The method of claim 5, wherein The phosphorus compound is an ester of phosphoric acid or phosphorous acid. Friction stability to lubricating oils, comprising adding to the lubricating oil a friction modifier comprising at least one hydrocarbyl substituent comprising 6 to 30 carbon atoms and at least one secondary amino group present in the polyamine chain is acylated with the corresponding amide group. How to give.