Dispersant reaction product with antioxidant capability

• US 7,645,726 B2
• Filed: 12/10/2004
• Issued: 01/12/2010
• Est. Priority Date: 12/10/2004
• Status: Active Grant

• Current Assignee: Afton Chemical Corporation
• Original Assignee: Afton Chemical Corporation
• Inventors: Loper, John T.
• Primary Examiner(s): Caldarola; Glenn
• Assistant Examiner(s): Goloboy; Jim
• Application Number:
  US11/008,198
• Publication Number:
  US 20060128571A1
• Time in Patent Office: 1,859 Days
• Field of Search: 508/242, 508/463
• US Class Current: 508/242
• CPC Class Codes: C07D 207/412 Acyclic radicals containing more than six carbon atoms
• CPC Class Codes: C10L 1/238 obtained otherwise than by reactions involving only carbon-to-carbon unsaturated bonds C10L1/221 takes precedence
• CPC Class Codes: C10L 10/04 for minimising corrosion or incrustation
• CPC Class Codes: C10L 10/06 for facilitating soot removal
• CPC Class Codes: C10L 10/18 use of detergents or dispersants for purposes not provided for in groups C10L10/02 - C10L10/16
• CPC Class Codes: C10M 133/16 Amides; Imides
• CPC Class Codes: C10M 159/12 Reaction products
• CPC Class Codes: C10M 2207/023 having hydroxy groups bound to carbon atoms of six-membered aromatic rings
• CPC Class Codes: C10M 2207/026 with tertiary alkyl groups
• CPC Class Codes: C10M 2207/289 containing free hydroxy groups
• CPC Class Codes: C10M 2215/26 Amines
• CPC Class Codes: C10M 2215/28 Amides; Imides
• CPC Class Codes: C10N 2030/04 Detergent property or dispersant property
• CPC Class Codes: C10N 2030/10 Inhibition of oxidation, e.g. anti-oxidants
• CPC Class Codes: C10N 2040/25 Internal-combustion engines
• CPC Class Codes: C10N 2040/252 Diesel engines
• CPC Class Codes: C10N 2070/02 Concentrating of additives

Abstract

A novel crankcase dispersant reaction product having fused therein an antioxidant moiety whereby the dispersant reaction product can function as an antioxidant while retaining at least two structural domains, one being a polar domain for association with sludge and a hydrocarbyl domain for oil solubility, so that the dispersant can function as a chemical agent to suspend sludge and prevent agglomeration of sludge precursors and soot so the latter can be readily removed from the system, such as by filtering, instead of being deleteriously deposited on internal engine components, as well as lubricant compositions incorporating such novel dispersant and, for instance, engines lubricated with such lubricant compositions.

Claims

1. A dispersant reaction product having an antioxidant moiety, at least one polar structural domain, and at least one hydrocarbyl structural domain, is obtained under conditions effective to react reactants that consist essentially of a hindered phenolic antioxidant ester and a reactable dispersant, said reactable dispersant comprising a Mannich dispersant.

2. A dispersant reaction product according to claim 1, wherein said hindered phenolic antioxidant ester is represented by the structure:

3. A dispersant reaction product according to claim 2, wherein R represents —

OC_1-6.

4. A dispersant reaction product according to claim 2, wherein R₁ is on alkyl group of 1 to 6 carbon atoms.

5. A dispersant reaction product according to claim 2, wherein R₂ represents an alkyl group of 1 to 6 carbon atoms.

6. A dispersant reaction product according to claim 2, wherein at least one of R₁ and R₂ represents a tert-butyl group.

7. A dispersant reaction product according to claim 3, wherein R represents —

OCH₃.

8. A dispersant reaction product according to claim 3, wherein R₃ represents a methyl group of hydrogen.

9. A dispersant reaction product according to claim 1, wherein the conditions include using a radio of molar equivalents of hindered phenolic compound to reactable dispersant of 0.01 n to n, wherein n represents the number of nitrogen atoms in said reactable dispersant.

10. A lubricating composition comprising

a major amount of base oil;

and

a minor amount of a dispersant reaction product according to claim 1.

11. An internal combustion engine lubricated with a lubricating composition according to claim 10.

12. A method for lowering soot and sludge deposits in an internal combustion engine comprising lubricating an internal combustion engine with a lubricating composition according to claim 10.

13. A method for improving dispersion of soot in a diesel engine comprising lubricating said diesel engine with a composition according to claim 10.

14. A formulated additive package comprising a dispersant according to claim 1, optionally at least one other additive suitable for an oil-based lubricating composition, and a minor amount of an oil.

15. A formulated additive package according to claim 14, wherein said additive package comprises 10 wt. % to 80 wt. % of said dispersant.

16. A dispersant reaction product having an antioxidant moiety, at least one polar structural domain, and at least one hydrocarbyl structural domain, obtained under conditions effective to react reactants that consist essentially of a hindered phenolic antioxidant ester and a reactable dispersant, said reactable dispersant comprising a succinimide-based dispersant or a Mannich-based dispersant, said hindered phenolic antioxidant ester being represented by the structure: