US3862981A

US3862981A - New lubricating oil additives

Info

Publication number: US3862981A
Application number: US267048A
Authority: US
Inventors: Bernard Demoures; Daniel Llauro; Francois Giolito
Original assignee: Rhone Progil SA
Current assignee: Rhone Progil SA
Priority date: 1971-07-08
Filing date: 1972-06-28
Publication date: 1975-01-28
Anticipated expiration: 1992-01-28
Also published as: FR2144631A1; DE2233295C3; BR7204515D0; PL84994B1; SU436487A3; AT322079B; ES404631A1; AT325030B; GB1354442A; IT958068B; SE395448B; NL7208506A; DD102727A5; ZA724628B; BE786032A; RO62306A; LU65684A1; DE2233295A1; CA960640A; CH562315A5

Abstract

New lubricating oil additives are provided comprising the reaction product of diphenylolpropane with an aliphatic chain substituted-succinic anhydride or acid, which aliphatic chain substituent is substantially saturated and contains at least about 30 carbon atoms, said reaction product being neutralized with an amine, preferably a polyamine, such as a polyalkylenepolyamine. Lubricating oils, fuel oils, and carburants containing the new additives have excellent detergent, dispersing and anti-rust properties.

Description

United States Patent 1 1 Demoures et al.

1 1 Jan. 28, 1975 NEW LUBRICATING ()IL ADDITIVES [75] Inventors: Bernard Demoures, Puteaux', Daniel Llauro, Crepieux Le Papc; Francois Giolito, Lyon, all of France [30] Foreign Application Priority Data July 8. 1971 France 71/26025 [52] LBS. Cl. 260/479 S, 44/71, 252/51.5 A [51] Int. Cl C07c 69/00, COlm 3/26 [58] Field of Search 260/479 R, 479 S; 252/515 A [56] References Cited UNITED STATES PATENTS 3.278.550 10/1966 Norman et al 252/515 A Le Suer 252/515 A Honnen et al. 252/515 A 7/1970 ll/l97l Primary I:'.ruminw-Paul F. Shaver [57] ABSTRACT New lubricating oil additives are provided comprising the reaction product of diphenylolpropane with an aliphatic chain substituted-succinic anhydride or acid. which aliphatic chain substituent is substantially saturated and contains at least about 30 carbon atoms. said reaction product being neutralized with an amine, preferably a polyamine, such as a polyalkylenepolyamine. Lubricating oils, fuel oils, and carburants containing the new additives have excellent detergent, dispersing and anti-rust properties.

8 Claims, N0 Drawings 1 NEW LUBRICATING OIL ADDITIVES BACKGROUND OF THE INVENTION The present invention relates to new lubricating oil additives which impart to lubricating oils good detergent, dispersing and anti-rust properties. This invention relates also to lubricating oils and to fuels and carbura'nts containing said additives.

There are known to the prior art, additives for lubricating oils which consist of derivatives of succinic acid or anhydride substituted with slightly unsaturated hydrocarbons. This class of additives, which has been known for some years, was an important development to the lubricating oil art. They consist mainly of reaction products of succinic acylating agents, substituted with a fairly saturated hydrocarbon radical containing an aliphatic chain of at least about 50 carbon atoms, with amines or alcohols.

Though the performances of such prior art additives are acceptable, it is desirable and even necessary to improve them. Those additives of the prior art which are esters have deficiencies with regard to their behavior to high temperatures and to their lack of resistance to hydrolysis. The esters are good anti-rust agents, but they have a limited dispersing power. Those additives which are aminated derivatives are good ashless dispersing agents, but they possess poor anti-rust properties.

It is an object of the present invention to provide a lubricating oil additive which does not have the shortcomings of the prior art additives.

It is also an object of the present invention to provide lubricating oils containing the new additives and which oils have improved dispersing, detergent and anti-rust properties.

Another object of the present invention is the provision of a lubricating oil additive having improved properties over those of the prior art alkyl substituted succinic esters described, for example, in U.S. Pat. No. 3,381,022 granted Apr. 30, 1968, and also with regard to the amide derivatives described in U.S. Pat. No. 3,172,892 of Mar. 9, 1965.

Other objects of the invention will be apparent to those skilled in the art from the present description.

GENERAL DESCRIPTION OF THE INVENTION The lubricating oil additives of the present invention comprise reaction products of diphenylolpropane with an hydrocarbon chain substituted succinic anhydride or acid, which hydrocarbon chain substituent is substantially saturated and contains at least 30 and preferably at least 50, carbon atoms, said resulting product being then neutralized with a polyamine, such as a polyalkylenepolyamine. After an extensive research investigation it has been found that these additives impart improved detergency, dispersing and anti-rust properties to lubricating oils, fuel oils and carburants.

These novel additives and products of the invention are produced in the form of a complex mixture, rather than a precise chemical compound, of which it is difficult to determine the exact chemical composition and the relative proportions present of the various constituents. It is for this reason that the products must be described in terms of the process of manufacturing them. The presence of the ester grouping resulting from the reaction of the diphenylolpropane and the substituted succinic anhydride or acid has been confirmed by infrared analysis. The esterification reaction between the substituted succinic acid or anhydride and diphenylolpropane results in an equilibrium difficult to displace; the resulting product contains in solution a variable proportion of the unreacted succinic acylating agent and, as a dispersion in said solution, unreacted diphenylolpropane. It is essential, in order to obtain good dispersing properties when employing the product as a lubricating oil additive, to neutralize the unreacted acylating agent with an amino compound. The unreacted diphenylolpropane may be removed, if it is in a large excess, by any convenient way such as filtration, centrifugation, etc.

The hydrocarbon chain-substituted succinic acid or anhydride starting materials used in the present invention are those resulting from the reaction ofmaleic acid or anhydride with a polyolefin, such as polyethylene, polypropylene, polybutylene, polyisobutylene, etc. having a molecular weight sufficient to provide a carbon content of at least about 30 atoms, preferably at least about 50 carbon atoms. The hydrocarbon chain is preferably aliphatic in nature. As a practical matter, the molecular weight of such polyolefins is at least about 400. It is also possible to use a chlorinated polyolefin, such as chloropolyethylene, which is reacted with maleic acid or anhydride. All that is necessary is to react the maleic anhydride with the polyolefin or chlorinated polyolefin at a temperature of between about 150 and 250C. The reaction product is the polyolefin-substituted succinic anhydride. The substantially saturated hydrocarbon substituent of the succinic radical may contain polar groups in minor proportions: chloro, nitro, etc. Hydrolysis of this product by water or steam treatment will produce the corresponding succinic acid.

The esterification reaction of diphenylolpropane with the aliphatic substituted succinic anhydride or acid may be achieved in the presence of a classical esterification catalyst, i.e., a base or acid, such as pyridine or its hydrochloride, sulfuric acid, para-toluenesulfonic acid and ion exchange resins having a strongly or moderately acid character. It may also be achieved without any catalyst. This esterification reaction occurs preferably at a temperature from about 50 to 300C, preferably between about and 200C, with or without a solvent such as xylene, toluene, etc. The solvent simplifies both temperature control and water removal from the reaction mixture.

The relative proportions of the two constituents, diphenylolpropane and aliphatic substituted succinic acid or anhydride, may vary within large limits. But in any event, since esterification is usually not complete, the remaining acid or anhydride must afterwards be neutralized with an aminated compound. Such neutralization is an important feature of the invention, as it is necessary to obtain good dispersing properties. The unreacted diphenylolpropane, finely dispersed in the product resulting from the esterification reaction, may be removed if it is in a substantial quantity. Otherwise it may remain in the product in a divided form without involving any disadvantage or incompatibility.

The esterification reaction involves a time duration of between about 1 and 10 hours, preferably 2 to 6 hours. It may occur under the normal atmospheric pressure, or under an elevated or reduced pressure, or in an atmosphere of inert gas.

The unreacted substituted succinic acid or anhydride present in the product resulting from esterification is DETAILED DESCRIPTION OF THE INVENTION In order to disclose more clearly the nature of the present invention, the following examples illustrating the invention are given. It should be understood, however, that this is done solely by way of example and is intended neither to delineate the scope of the invention nor limit the ambit of the appended claims. In the examples which follow, and through the specification, the quantities of material are expressed in terms of parts by weight, unless otherwise specified. The acylating agent used in Examples 1 to 6 hereinbelow is the reaction product of 350 grams of maleic anhydride and 2500 grams of polyisobutene with a molecular weight equal to about 1000.

EXAMPLE 1 2 kilograms of polyisobutylene substituted-succinic anhydride, prepared as hereinabove [Pibsa index 53 Pibsa index (for polyisobutenyl succinic anhydride) is the number of potash milligrams which are necessary for neutralizing 1 gram of product] were reacted with 107 grams of diphenylol propane in the presence of 21 grams of p-toluenesulfonic acid catalyst for 4 hours at a temperature of 160C. The product was then vaporized under vacuum at 160C. for 1 hour, and neutralized with 82 grams of tetraethylenepentamine at 155C. for 2 hours, under a partial vacuum (400 mm. Hg. pressure, approximately). This treatment was followed with a vaporization at mm. Hg. pressure for 30 minutes. Nitrogen content in the final product was 1.29%.

EXAMPLE 2 62.5 grams of diphenylolpropane were heated at 170C. 484 grams of polyisobutylene substitutedsuccinic acid prepared as hereinabove (Pibsa Index 63.5) were introduced over 15 minutes at 170C. under 400 mm. Hg. pressure. The reaction proceeded for 4 hours (170C. under partial vacuum). 543 grams of the resulting product were treated afterwards with 21.5 grams of tetraethylenepentamine under the same conditions as in Example 1. Nitrogen content in final product was 1.40%.

EXAMPLE 3 64 grams of diphenylolpropane were heated in the presence of 472 grams of xylene at 1 l0-115C. Then 1257 grams of polyisobutylene substituted-succinic anhydride prepared as hereinabove, (Pibsa Index 62.5 were introduced over a period of minutes. After 1 hour of reaction at 110115C., 13.2 grams ofpyridine were added. A second addition of an equal amount of pyridine was made after 2 hours of reaction. After 3.5 hours of reaction, the product is vapourized at 140C. under 20 mm. Hg. pressure for minutes.

EXAMPLE 4 200 grams ofthe product of Example 3 were neutralized with 5.6 grams of tetraethylene pentamine under the same conditions as in Example 1. Nitrogen content of the final product was 1%.

EXAMPLE 5 200 grams of the product of Example 3 were neutralized with 7.7 grams of triethylenetetramine under the same conditions as in Example 1. Nitrogen content of the final product was 1.42%.

EXAMPLE 6 6640 grams of polyisobutylene substituted-succinic anhydride (Pibsa Index 76.3) were reacted with 465 grams of diphenylolpropane in the presence of 53 grams of para-toluene sulfonic acid for 2.5 hours at 162.5C. Then the product was vapourized under vacuum for 1.5 hours. 667 g. of the resulting product were neutralized with 23.1 grams of tetraethylenepentamine under the same conditions as in Example 1. Nitrogen content of the final product obtained in this way was 1.23%.

EXAMPLE 7 The acylating agent employed in this example was the reaction product of maleic anhydride with a polyisobutene having a molecular weight equal to about 455, heated at a temperature between 190 and 240C. for 10 hours.

200 grams of the resulting polyisobutylene substituted-succinic anhydride (Pibsa Index 81) were reacted with 16.46 grams of diphenylolpropane and 2.1 grams of p-toluene-sulfonic acid over 4 hours at 170C. and for 30 minutes under vacuum at 170C. 201 grams of the resulting product were reacted with 9 grams of tetraethylenepentamine at C. for 2 hours under partial vacuum (about 400 mm. Hg. pressure). Treatment was completed under vacuum of 20 mm. Hg. pressure for 30 minutes. Nitrogen content of the final product was 1.44%.

It will be apparent that in the foregoing examples other polyolefin substituted succinic anhydrides may be employed such as those of polyethylene, polypropylene and polypentene, etc. Also, the amine employed for neutralization may be diethylenetriamine or pentaethylenehexamine, etc.

The additive products of the invention, including the products of the foregoing examples, are desirably employed in lubricating oils, fuel oils and carburants. in amounts of between about 0.01 and 10%, preferably between 0.1 and 3%, by weight of oil.

The foregoing products according to the present invention were tested with regard to anti-rust and dispersing properties in lubricating agents.

The tests of the dispersing power were conducted according to the stain method described in Volume 1 of A. Schillings book Les huiles pour moteurs et le graissage des moteurs (Oils for motors and motor greasing), edition of 1962, pages 89-90. Stains were achieved with the additive dissolved in a lubricating oil of SAE 30. Sludge was added in order to obtain a content of carbonaceous substances of 0.36%. There are five stains obtained:

1. after heating at 200C. for 10 minutes 2. after heating at 250C. for 10 minutes 3. after-heating at 200C. for minutes (at the outset 1% of water was added) 4. after heating at 200C. during 1 minute (initially 1% of water was added) 5. after adding of 1% of water, in the cold state Readings were made after 48 hours. For every stain, the dispersed sludge percentage is expressed with regard to the oil stain and calculated from the respective diameters. The higher the percentages of dispersed product; the better is the dispersion with regard to sludge.

For the products in accordance with the present invention of the foregoing examples the following values were obtained:

Example 1 product= 308 Example 2 product 306 Example 4 product 301 Example 5 product 312 A comparison was made of the dispersing values obtained by the same test method with other products such as a non-neutralized ester and prior products commonly used,'considered as typical of the present state of the art. Listed below are the values obtained:

Product of Example 3'(non-neutralized product) 200 Monosuccinimide 268 Bis succinimide 274 Ester of substituted succinic acid and pentaerythritol 265 Ester of substituted succinic acid and glycerol 250 Ester of substituted succinic acid and phenol MONOSUCCINIMIDE PREPARATION 250' grams of polyisobutylene substituted-succinic anhydride having a Pibsa index 53 were reacted with 18 grams of tetraethylenepentamine at 155C. for 2 hours, under partial vacuum (about 400 mm. Hg. pressure). Treatment was followed with a vapourization under 20 mm. Hg. pressure for minutes. Nitrogen content of the final product was 2.46%.

BIS-SUCCINIMIDE PREPARATION 250 grams of polyisobutylene substituted-succinic anhydride having a Pibsa index 55 were reacted with 8.6 grams of triethylenetetramine at 155C. for 2 hours, under a partial vacuum (about 400 mm. Hg. pressure). Treatment was followed by a vapourization under 20 mm. Hg. pressure for 30 minutes. Nitrogen content of the final product was 1.32%.

PREPARATION OF SUBSTITUTED SUCCINIC ACID AND PENTAERYTHRITOL ESTER 1258 grams of polyisobutylene substituted-succinic anhydride (Pibsa index 62.5 were reacted with 94 grams of pentaerythritol for 3.5 hours at 135-145C.

then for 2 hours at 175185C. Unreacted pentaerythritol was removed by filtration. The filtrate constituted ester.

PREPARATION OF GLYCEROL AND SUBSTITUTED SUCCINIC ANHYDRIDE ESTER 898 grams of polyisobutylene substituted-succinic anhydride with a Pibsa Index 62.5 were reacted with 46 grams of glycerol for 3 hours at C., then for 3 hours at 190C. The reaction product was the desired ester.

PREPARATION OF PHENOL AND SUBSTITUTED SUCCINIC ACID ESTER 898 grams of polyisobutylene substituted-succinic anhydride with a Pibsa index 62.5 were reacted with 376 grams of phenol in the presence of 190 grams of xylene for 1 hour at -l65C. Afterwards 12.7 grams of p-toluene sulfonic acid were added. The reaction proceeded for 30 minutes at l60-l65C. This operation was repeated twice. Finally, xylene, residual phenol and catalyst were removed under vacuum (160165C. during 30 minutes 10 to 20 mm. Hg. pressure). The final product was the ester.

The anti-rust characteristics of the products according to the invention have been tested in the laboratory with favorable results. The general tendency has been confirmed by motor tests (sequence II B, gasoline motor V-8 of a 1967 Oldsmobile). The basic formulation to which the additive was added was composed of a calcium sulfonate, a calcium phenate and a zinc dithiophosphate. The following values expressing average engine rust (AER), were obtained (ideal value 10):

Basic formula plus Example 1 product AER 8.6

Basic formula plus Example 5 product AER 7.9

As a comparison of the prior art, the following value was obtained:

Basic formula plus bis succinimide AER 7.2

The entirety of the test results set forth hereinabove shows quite well the important improvement provided by the additives for lubricating oils produced according to the invention and characterizes the technical progress that such new products have achieved.

The terms and expressions which have been employed are used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed.

What is claimed is:

1. An additive consisting of the ester reaction product of diphenylolpropane with an hydrocarbon substituted-succinic anhydride or acid, wherein the said hydrocarbon substituent is substantially saturated and contains at least about 30 carbon atoms, said reaction product being neutralized with a polyamine.

2. An additive in accordance with claim 1, wherein said polyamine is a polyalkylenepolyamine.

3. An additive in accordance with claim 2, wherein said polyalkylenepolyamine is a member selected from the class consisting of diethylenetriamine, triethylenetetramine, tetraethylenepentamine and pentaethylenehexamine.

4. An additive in accordance with claim 1, wherein said hydrocarbon substituent is a polyolefin radical.

8 class consisting of polyethylene, polypropylene polybutylene. polyisobutylene. polypentene-l and chlorinated polyolefins.

8. An additive in accordance with claim 1. wherein the esterification reaction is conducted at a temperature of between about 50 and 300C.

Claims

2. An additive in accordance with claim 1, wherein said polyamine is a polyalkylenepolyamine.
3. An additive in accordance with claim 2, wherein said polyalkylenepolyamine is a member selected from the class consisting of diethylenetriamine, triethylenetetramine, tetraethylenepentamine and pentaethylenehexamine.
4. An additive in accordance with claim 1, wherein said hydrocarbon substituent is a polyolefin radical.
5. An additive in accordance with claim 1, wherein said hydrocarbon substituent is a chlorinated polyolefin radical.
6. An additive in accordance with claim 1, wherein said hydrocarbon substituent contains at least about 50 carbon atoms.
7. An additive in accordance with claim 4, wherein said polyolefin radical is derived from a member of the class consisting of polyethylene, polypropylene, polybutylene, polyisobutylene, polypentene-1 and chlorinated polyolefins.
8. An additive in accordance with claim 1, wherein the esterification reaction is conducted at a temperature of between about 50* and 300*C.