Supplemental rust inhibitors and rust inhibition in internal combustion engines

• US 5,204,012 A
• Filed: 01/31/1989
• Issued: 04/20/1993
• Est. Priority Date: 01/31/1989
• Status: Expired due to Fees

• Current Assignee: Ethyl Corporation (Newmarket Corporation)
• Original Assignee: Ethyl Corporation (Newmarket Corporation)
• Inventors: Schaffhausen, John G.
• Primary Examiner(s): MEDLEY, MARGARET B
• Application Number:
  US07/304,765
• Time in Patent Office: 1,540 Days
• Field of Search: 252/56 R, 252/52 A, 252/396, 252/407, 252/32.7 E, 252/51.5 R, 252/57, 252/396, 252/407, 560/183, 560/186
• US Class Current: 508/399
• CPC Class Codes: C10M 137/10 Thio derivatives
• CPC Class Codes: C10M 145/38 esterified
• CPC Class Codes: C10M 159/16 obtained by Mannich reactions
• CPC Class Codes: C10M 159/24 containing sulfonic radicals
• CPC Class Codes: C10M 167/00 Lubricating compositions characterised by the additive being a mixture of a macromolecular compound, a non-macromolecular compound and a compound of unknown or incompletely defined constitution, each of these compounds being essential
• CPC Class Codes: C10M 2209/104 of alkylene oxides containing two carbon atoms only
• CPC Class Codes: C10M 2209/107 of two or more specified different alkylene oxides covered by groups C10M2209/104 - C10M2209/106
• CPC Class Codes: C10M 2209/109 esterified
• CPC Class Codes: C10M 2215/04 having amino groups bound to acyclic or cycloaliphatic carbon atoms
• CPC Class Codes: C10M 2215/26 Amines
• CPC Class Codes: C10M 2217/043 Mannich bases
• CPC Class Codes: C10M 2217/046 Polyamines, i.e. macromoleculars obtained by condensation of more than eleven amine monomers
• CPC Class Codes: C10M 2217/06 Macromolecular compounds obtained by functionalisation op polymers with a nitrogen containing compound
• CPC Class Codes: C10M 2219/022 of hydrocarbons, e.g. olefines polyolefins C10M2221/041
• CPC Class Codes: C10M 2219/046 Overbasedsulfonic acid salts
• CPC Class Codes: C10M 2219/087 containing hydroxy groups; Derivatives thereof, e.g. sulfurised phenols
• CPC Class Codes: C10M 2219/088 Neutral salts
• CPC Class Codes: C10M 2219/089 Overbased salts
• CPC Class Codes: C10M 2223/045 Metal containing thio derivatives
• CPC Class Codes: C10N 2010/04 Groups 2 or 12
• CPC Class Codes: C10N 2040/25 : Internal-combustion engines
• CPC Class Codes: C10N 2040/251 : Alcohol fueled engines
• CPC Class Codes: C10N 2040/252 : Diesel engines
• CPC Class Codes: C10N 2040/253 : Small diesel engines
• CPC Class Codes: C10N 2040/255 : Gasoline engines
• CPC Class Codes: C10N 2040/28 : Rotary engines

Abstract

An esterification product obtained by reacting ethylene oxide/propylene oxide block copolymer with a long-chain monocarboxylic acid, when employed as a supplemental rust inhibitor in lubricating oils for internal combustion engines, has been found to furnish excellent rust inhibition in the engines and to be compatible with other components in the lubricating oils.

A lubricating oil composition containing such product may be used to inhibit rust formation in an internal combustion engine.

Claims

1. A lubricating oil composition comprising a major amount of a hydrocarbon oil of lubricating viscosity, a minor amount of a dispersant, a minor amount of a primary rust inhibitor, and from about 0.03% to about 1 wt. %, based on the weight of the oil composition, of an esterification product having a total acid number (TAN) that is in the range of about 10 to about 40 and being prepared by reacting in the presence of a catalyst and at a temperature in the range of about 25°

C. (77°

F.) to about 111°

C. (232°

F.) ethylene oxide/propylene oxide block copolymer with a long-chain monocarboxylic acid having an alkyl radical with sufficient carbon atoms to provide solubility of said product in said composition.

2. The composition of claim 1, wherein said monocarboxylic acid is oleic acid or linoleic acid.

3. The composition of claim 1, wherein said monocarboxylic acid is oleic acid and is present in an amount to provide a ratio of oleic acid to said copolymer that is in the range of about 1 to about 5 equivalents of oleic acid per equivalent of copolymer.

4. The composition of claim 3, wherein said reacting is carried out in the presence of p-toluene sulfonic acid catalyst, said p-toluene sulfonic acid being present in an amount in the range of about 1 mole % to about 20 mole % p-toluene sulfonic acid, based on the amount of copolymer.

5. The composition of claim 1, wherein said reacting is carried out in the presence of a catalyst and at a temperature in the range of about 25°

C. (77°

F.) to about 111°

C. (232°

F.).

6. The composition of claim 5, wherein said catalyst is p-toluene sulfonic acid, said p-toluene sulfonic acid being present in an amount in the range of about 1 mole % to about 20 mole % p-toluene sulfonic acid, based on the amount of copolymer.

7. The composition of claim 6, wherein said reacting is carried out in the presence of a solvent.

8. The composition of claim 1, wherein said reacting is carried out in the presence of a solvent.

9. The composition of claim 1, wherein said dispersant is a Mannich polyamine dispersant and wherein said composition further comprises (i) a minor amount of overbased metal sulfonate selected from the group consisting of overbased calcium sulfonate and overbased magnesium sulfonate and (ii) a minor amount of zinc dialkyldithiophosphate.

10. A method for operating an internal combustion engine to inhibit rust formation, which method comprises lubricating said engine with a lubricating oil composition comprising a major amount of a hydrocarbon oil of lubricating viscosity, a minor amount of a dispersant, a minor amount of a primary rust inhibitor, and from about 0.03% to about 1 wt. % based on the weight of the oil composition of a compatible lubricating oil supplemental rust inhibitor consisting essentially of a reaction product having a total acid number (TAN) that is in the range of about 10 to about 40 of a nonionic polyol ether ethylene oxide/propylene oxide block copolymer of a molecular weight of from about 2000 to about 3000, which is borderline water dispersible to water insoluble, with a long-chain monocarboxylic acid having an alkyl radical with sufficient carbon atoms to provide solubility of said product in said composition.

11. The method of claim 10, wherein said monocarboxylic acid is oleic acid or linoleic acid.

12. The method of claim 10, wherein said monocarboxylic acid is oleic acid and is present in an amount to provide a ratio of oleic acid to said copolymer that is in the range of about 1 to about 5 equivalents of oleic acid per equivalent of copolymer.

13. The method of claim 12, wherein said reacting is carried out in the presence of p-toluene sulfonic acid catalyst, said p-toluene sulfonic acid being present in an amount in the range of about 1 mole % to about 20 mole % p-toluene sulfonic acid, based on the amount of said copolymer.

14. The method of claim 10, wherein said reacting is carried out in the presence of a catalyst and at a temperature in the range of about 25°

C. (77°

F.) to about 111°

C. (232°

F.)

15. The method of claim 14, wherein said catalyst is p-toluene sulfonic acid, said p-toluene sulfonic acid being present in an amount in the range of about 1 mole % to about 20 mole % p-toluene sulfonic acid, based on the amount of copolymer.

16. The method of claim 15, wherein said reacting is carried out in the presence of a solvent.

17. The method of claim 10, wherein said reacting is carried out in the presence of a solvent.

18. The method of claim 10, wherein said dispersant is a Mannich polyamine dispersant and wherein said composition further comprises (i) a minor amount of overbased metal sulfonate selected from the group consisting of overbased calcium sulfonate and overbased magnesium sulfonate and (ii) a minor amount of zinc dialkyldithiophosphate.