High performance grease compositions

Patent metadata

Field	Value
Publication number	US-12570918-B2
Application number	US-202318166531-A
Country	US
Kind code	B2
Filing date	Feb 9, 2023
Priority date	Feb 10, 2022
Publication date	Mar 10, 2026
Grant date	Mar 10, 2026

Abstract

This invention relates to overbased calcium sulfonate complex grease compositions prepared without boric acid and alcohol promotors containing anti-wear, anti-friction, thermal & oxidation stability additives.

First claim

The invention claimed is:

1 . A method for making a high performance overbased calcium sulfonate complex grease composition prepared without boric acid and without the use of any alcohol-based promotors comprising reacting and mixing
(a) a primary overbasing material comprising overbased oil-soluble calcium sulfonate having amorphous calcium carbonate dispersed therein; (b) a suitable base oil of an amount appropriate to provide a final acceptable product consistency; (c) in the presence of a functionalized polymer, a stoichiometric excess of finely divided calcium carbonate as an oil-insoluble solid calcium containing base added to the primary overbasing material and base oil before conversion; and (d) a doping agent in the form of an extreme-pressure, anti-wear, antioxidant, metal deactivator or polymeric additive, or combination thereof wherein the mixture is heated at a rate of less than 1° C. per minute to a temperature of 45-50° C.

2 . The method of claim 1 , further comprising the addition of a carboxylic acid between steps (c) and (d) selected from the group consisting of a long chain aliphatic carboxylic acid with at least 12 carbon atoms.

3 . The method of claim 2 wherein the amount of overbased oil-soluble calcium sulfonate is between 10 and 35% by weight.

4 . The method of claim 3 , wherein the amount of the overbased oil-soluble calcium sulfonate is between 18 and 25% by weight.

5 . The method of claim 4 , wherein the total amount of base oil added is between 25% and 80% by weight.

6 . The method of claim 5 , wherein the total amount of base oil added is between 35% and 75% by weight.

7 . The method of claim 6 , wherein the total amount of base oil added is between 40% and 70% by weight.

8 . The method of claim 5 , wherein the amount of long chain carboxylic acid is between 1% and 6% by weight.

9 . The method of claim 8 , wherein the amount of long chain carboxylic acid is between 2.0% and 3.5% by weight.

10 . The method of claim 8 , wherein the amount of doping agent is between 0.5-15% by weight.

11 . The method of claim 10 , wherein the amount of doping agent is between 5-12% by weight.

12 . The method of claim 10 wherein the resulting grease composition contains an insoluble portion of crystalline capsule morphology.

13 . The method of claim 12 , wherein the crystalline capsule morphology has a length of about 16.4+/−6.4 nm and a width of about 5.7+/−1.3 nm.

14 . The method of claim 1 , further comprising increasing the temperature to 90±10° C.; raising the temperature to 160±10° C.; and cooling to 110±10° C.

15 . The method of claim 1 , further comprising adding an anionic surfactant selected from the group consisting of a hydrophilic sulfonate head-group and a hydrophobic alkylbenzene tail-group.

16 . The method of claim 15 , wherein the anionic surfactant is alkyl benzene sulfonic acid.

17 . The method of claim 12 , wherein the grease composition has a weld load of at least 800 kgs according to ASTM D2596.

18 . The method of claim 12 , wherein the grease composition has a high temperature life greater than 280 hours according to ASTM D3527.

19 . A grease composition comprising the reaction product made from components which comprise:
(a) an overbased oil-soluble calcium sulfonate having amorphous calcium carbonate dispersed therein present in an amount of 18-25 weight percent; (b) a base oil present in an amount of 40-70 weight percent; (c) a functionalized polymer that acts as a binding medium between the overbased calcium sulfonate and base oil; (d) a long chain carboxylic acid having at least 12 carbon atoms present in an amount of 2.0-3.5 weight percent; (e) acetic acid present in an amount of 0.5-1.0 weight percent; (f) an anionic surfactant comprising a hydrophilic sulfonate head-group and a hydrophobic alkylbenzene tail-group; and (g) a doping agent selected from the group consisting of extreme-pressure additives, anti-wear additives, antioxidants, metal deactivators, polymeric additives, and combinations thereof present in an amount of 5-12 weight percent; wherein the grease composition comprises an insoluble portion having crystalline capsule morphology with a length of 16.4+/−6.4 nm and a width of 5.7+/−1.3 nm, and wherein the grease composition exhibits a weld load of at least 800 kgs according to ASTM D2596 and a high temperature life greater than 280 hours according to ASTM D3527.

Assignees

• Chevron Usa Inc

Inventors

• Kumar Anoop

Classifications

• C10N2050/10

  semi-solid; greasy · CPC title

• C10N2020/06

  Particles of special shape or size · CPC title

• C10M2219/0466

  used as thickening agents · CPC title

• C10M2207/128

  containing hydroxy groups; Ethers thereof · CPC title

• C10M2207/122

  monocarboxylic · CPC title