1,3-dithiolane-2-thione additives for lubricants and fuels
View Patent ↗Fuels, especially hydrocarbon fuels, and lubricants, especially lubricating oils, contain a class of anti-corrosion, anti-wear, anti-fatigue, and extreme pressure additives that are derived from 1,3-dithiolane-2-thiones.
1. A composition comprising:
(A) a lubricant or a hydrocarbon fuel, and
(B) at least one 1,3-dithiolane-2-thione of formula (I):
wherein:
R 1 is a carboxy alkyl of the structure: (CH 2 ) p CO 2 R 5
wherein:
p is from 1 to 50, and
R 5 is selected from the group consisting of hydrocarbyl, chain-substituted saturated hydrocarbyl, and chain-substituted unsaturated hydrocarbyl;
R 2 , R 3 , and R 4 are independently selected from the group consisting of hydrogen, alkyl, and alkenyl;
wherein said alkyl and alkenyl groups are unsubstituted or substituted with OH, SH, oxirane, thiirane, or 1,3-dithiolane-2-thione.
2. The composition of claim 1 wherein the 1,3-dithiolane-2-thione is prepared by The reaction of an alkali metal xanthate with an epoxidized olefin of from 8 to 36 carbons.
3. The composition of claim 2 wherein the epoxidized olefin is an α-olefin.
4. The composition of claim 2 wherein the epoxidized olefin is an epoxidized tallate ester.
5. The composition of claim 1 further comprising at least one phosphorus-containing additive.
6. The composition of claim 5 wherein at least one phosphorus-containing additive is a dihydrocarbyldithiophosphate.
7. The composition of claim 1 wherein the 1,3-dithiolane-2-thione is selected from the group consisting of hexahydro-1-3-benzodithiole-2-thione, 4-octyl-1,3-dithiolane-2-thione, 4-decyl-1,3-dithiolane-2-thione, 4-dodecyl-1,3-dithiolane-2-thione, 4-tetradecyl-1,3-dithiolane-2-thione, and a 1,3-dithiolane-2-thione derivative of epoxidized 2-ethylhexyl tallate.
8. The 1,3-dithiolane-2-thione derivative of epoxidized 2-ethylhexyl tallate.
9. A method for improving the anti-corrosion, anti-fatigue, anti-wear, and extreme pressure properties of lubricants and hydrocarbon fuels comprising adding to said lubricants and hydrocarbon fuels a functional property-improving amount of at least one 1,3-dithiolane-2-thione of formula (I):
wherein:
R 1 is a carboxy alkyl of the structure: (CH 2 ) p CO 2 R 5
wherein:
p is from 1 to 50, and
R 5 is selected from the group consisting of hydrocarbyl, chain-substituted saturated hydrocarbyl, and chain-substituted unsaturated hydrocarbyl;
R 2 , R 3 , and R 4 are independently selected from the group consisting of hydrogen, alkyl, and alkenyl;
wherein said alkyl and alkenyl groups are unsubstituted or substituted with OH, SH, oxirane, thiirane, or 1,3-dithiolane-2-thione.
10. The method of claim 9 wherein a phosphorus-containing additive is also added to The lubricants and hydrocarbon fuels.
11. The method of claim 10 wherein the phosphorus-containing additive is a dihydrocarbyldithiophosphate.
12. The method of claim 9 wherein the 1,3-dithiolane-2-thione is selected from the group consisting of hexahydro-1-3-benzodithiole-2-thione, 4-octyl-1,3-dithiolane-2-thione, 4-decyl-1,3-dithiolane-2-thione, 4-dodecyl-1,3-dithiolane-2-thione, 4-tetradecyl-1,3-dithiolane-2 -thione, and a 1,3-dithiolane-2-thione derivative of epoxidized 2-ethylhexyl tallate.
13. A method for producing a 1 ,3-dithiolane-2-thione of formula (I):
wherein:
R 1 is selected from the group consisting of hydrogen, alkyl, alkoxy, and carboxy alkyl of the structure: (CH 2 ) p CO 2 R 5
wherein:
p is from 1to 50;
R 5 is selected from the group consisting of hydrocarbyl, chain-substituted saturated hydrocarbyl, and chain-substituted unsaturated hydrocarbyl;
R 2, R 3, and R 4 are independently selected from the group consisting of hydrogen, alkyl, and alkenyl;
wherein said alkyl and alkenyl groups are unsubstituted or substituted with OH, SH, oxirane, thiirane, or 1 ,3-dithiolane-2-thione; or
R 1 and R 3 are fused together to form a ring of from 3 to 10 carbon atoms, which can be further substituted with alkyl, cycloalkyl, alkenyl, aryl or alkoxy groups, and can contain ether or ester functionalities, the method comprising:
reacting a sodium xanthate with an epoxidized 2-ethylhexyl tallate.