Alkylated alkoxydiarylamine antioxidants
Alkylated diaryl amines further substituted by an alkoxy group on one or more aryl carbon atoms exhibit excellent antioxidant activity in lubricant compositions.
1. An alkylated alkoxydiarylamine of formula III
wherein x is 0, 1 or 2 and y is 1, 2 or 3;
R′ is C 1-12 alkyl or C 1-12 alkyl substituted by one or more hydroxyl or alkoxy;
each R is independently C 4-24 alkyl, C 7-18 aralkyl, or C 4-24 alkyl substituted by one or more hydroxyl and/or interrupted by one or more oxygen atom;
wherein the total number of carbon atoms of the combined groups R is 12 or higher,
and wherein the alkoxy group R′O is on the phenyl ring at the 2- or 3-position relative to the nitrogen atom.
2. The alkylated alkoxydiarylamine according to claim 1 , wherein x is 0 or 1 and y is 1 or 2.
3. The alkylated alkoxydiarylamine according to claim 1 , wherein R′ is C1-12 alkyl.
4. The alkylated alkoxydiarylamine according to claim 1 , wherein each R is independently C4-24 alkyl.
5. The alkylated alkoxydiarylamine according to claim 4 , wherein R′ is C1-6.
6. The alkylated alkoxydiarylamine according to claim 5 , wherein x is 0 or 1 and y is 1 or 2.
7. The alkylated alkoxydiarylamine according to claim 1 , wherein the total number of carbon atoms of the combined groups R is 16 or higher.
8. The alkylated alkoxydiarylamine according to claim 1 , wherein the alkoxy group R′O is on the phenyl ring at the 3-position relative to the nitrogen atom.
9. The alkylated alkoxydiarylamine according to claim 1 , wherein x is 1 and y is 1.
10. The alkylated alkoxydiarylamine according to claim 1 , wherein both aryl groups in the formula III are alkylated.
11. The alkylated alkoxydiarylamine according to claim 1 , wherein x is 0, y is 1, R′ is methyl or ethyl, and R is selected from dodecyl, octadecyl, and icosane.
12. The alkylated alkoxydiarylamine according to claim 1 , wherein x is 1, y is 1, R′ is methyl or ethyl, and R is selected from hexyl, octyl, nonyl, decyl, and dodecyl.
13. The alkylated alkoxydiarylamine according to claim 1 , wherein x is 1, y is 1, R′ is methyl or ethyl, and one R is n-butyl, sec-butyl, tert-butyl or hexyl and the other R is t-octyl, nonyl, dodecyl, hexadecyl or octadecyl.
14. The alkylated alkoxydiarylamine according to claim 1 , wherein x is 1, y is 1, R′ is butyl or hexyl, and R is selected from n-butyl, sec-butyl, iso-amyl, hexyl, octyl, nonyl, and dodecyl.