High- and low-viscosity estolide base oils and lubricants
Provided herein are compounds of the formula: in which n is an integer equal to or greater than 1; R 2 is selected from hydrogen and optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched; and R 1 , R 3 , and R 4 , independently for each occurrence, are selected from optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched, wherein compositions comprising the compounds are characterized by particular combinations of values for estolide number, kinematic viscosity, and pour point. Also provided are compositions containing the compounds and methods of making both the compounds and compositions thereof.
1. A composition comprising two or more estolide compounds, said composition having:
an EN selected from an integer or fraction of an integer that is equal to or greater than 4, wherein the EN is the average number of estolide linkages in compounds according to Formula I;
a kinematic viscosity equal to or greater than 200 cSt when measured at 40° C.; and
a pour point equal to or lower than −40° C.,
wherein said two or more estolide compounds are selected from compounds of Formula I:
wherein
x is, independently for each occurrence, an integer selected from 0 to 20;
y is, independently for each occurrence, an integer selected from 0 to 20;
n is an integer selected from 0 to 12;
R 1 is an optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched; and
R 2 is an optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched,
wherein each fatty acid chain residue of said two or more estolide compounds is independently optionally substituted.
2. The composition according to claim 1 , wherein
x is, independently for each occurrence, an integer selected from 1 to 10;
y is, independently for each occurrence, an integer selected from 1 to 10;
n is an integer selected from 0 to 8;
R 1 is an optionally substituted C 1 to C 22 alkyl that is saturated or unsaturated, and branched or unbranched; and
R 2 is an optionally substituted C 1 to C 22 alkyl that is saturated or unsaturated, and branched or unbranched,
wherein each fatty acid chain residue is unsubstituted.
3. The composition according to claim 1 , wherein
x+y is, independently for each fatty acid chain residue, an integer selected from 13 to 15; and
n is an integer selected from 0 to 6.
4. The composition according to claim 1 , wherein x+y is 15 for at least one fatty acid chain residue.
5. The composition according to claim 1 , wherein R 2 is a branched or unbranched C 1 to C 20 alkyl that is saturated or unsaturated.
6. The composition according to claim 5 , wherein R 2 is selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decanyl, undecanyl, dodecanyl, tridecanyl, tetradecanyl, pentadecanyl, hexadecanyl, heptadecanyl, octadecanyl, nonadecanyl, and icosanyl, which are saturated or unsaturated and branched or unbranched.
7. The composition according to claim 1 , wherein R 2 is selected from C 6 to C 12 alkyl.
8. The composition according to claim 7 , wherein R 2 is 2-ethylhexyl.
9. The composition according to claim 1 , wherein R 1 is selected from unsubstituted C 7 to C 17 alkyl that is unbranched and saturated or unsaturated.
10. The composition according to claim 1 , wherein R 1 is selected from C 13 to C 17 alkyl that is unsubstituted, unbranched, and saturated or unsaturated.
11. The composition according to claim 10 , wherein R 1 is selected from saturated C 13 alkyl, saturated C 15 alkyl, and saturated or unsaturated C 17 alkyl, which are unsubstituted and unbranched.
12. The composition according to claim 1 , wherein R 1 and R 2 are independently selected from optionally substituted C 1 to C 18 alkyl that is saturated or unsaturated, and branched or unbranched.
13. The composition according to claim 1 , wherein R 1 is selected from optionally substituted C 7 to C 17 alkyl that is saturated or unsaturated, and branched or unbranched; and R 2 is selected from an optionally substituted C 3 to C 20 alkyl that is saturated or unsaturated, and branched or unbranched.
14. The composition according to claim 1 , wherein said composition has an EN that is an integer or fraction of an integer selected from 4 to 5.
15. The composition according to claim 14 , wherein said composition has an EN that is a fraction of an integer selected from 4.2 to 4.8.
16. The composition according to claim 1 , wherein said composition has an EN selected from an integer or fraction of an integer that is equal to or greater than 5.
17. The composition according to claim 1 , wherein said composition has a kinematic viscosity of 200 cSt to 250 cSt at 40° C.
18. The composition according to claim 17 , wherein said composition has a kinematic viscosity of 210 cSt to 230 cSt at 40° C.
19. The composition according to claim 1 , wherein said composition has a pour point of −40° C. to −50° C.
20. The composition according to claim 19 , wherein said composition has a pour point of −42° C. to −48° C.
21. The composition according to claim 1 , wherein said composition has a pour point of less than −50° C.
22. The composition according to claim 21 , wherein said composition has a pour point of −50° C. to −60° C.
23. The composition according to claim 21 , wherein said composition has a pour point of −52° C. to −58° C.
24. The composition according to claim 1 , wherein said composition exhibits an iodine value (IV) of less than 15 cg/g.
25. The composition according to claim 24 , wherein said composition exhibits an iodine value (IV) of less than 10 cg/g.
26. The composition according to claim 1 , wherein said composition consists essentially of the two or more estolide compounds of Formula I.
27. The composition according to claim 1 , wherein R 2 is an unsubstituted alkyl that is saturated or unsaturated, and branched or unbranched.
28. The composition according to claim 1 , wherein R 1 is an unsubstituted alkyl that is saturated or unsaturated, and branched or unbranched.
29. The composition according to claim 1 , wherein R 1 is optionally substituted with a group that is not hydroxyl.
30. The composition according to claim 1 , wherein said two or more estolide compounds are derived from a process that comprises forming a covalent bond between an oxygen of a carboxylic group of at least one first fatty acid and a carbon of at least one site of unsaturation of at least one second fatty acid.