U.S. patent application number 10/275368 was filed with the patent office on 2003-09-11 for stabilizing compositions for lubricating oils.
Invention is credited to Holt, Alan, Mulqueen, Gerard.
Application Number | 20030171227 10/275368 |
Document ID | / |
Family ID | 9891265 |
Filed Date | 2003-09-11 |
United States Patent
Application |
20030171227 |
Kind Code |
A1 |
Holt, Alan ; et al. |
September 11, 2003 |
Stabilizing compositions for lubricating oils
Abstract
Stabilising compositions for lubricant base stocks and lubricant
formulations are composed of a mixture of (a) at least one aromatic
aminic amine antioxidant optionally blended with at least one
hindered phenolic antioxidant and (b) at least one neutral organo
phosphate or phosphite, optionally blended with at least one acid
organo phosphate or phosphite. These stabilising composition
mixtures are characterised by their stabilising capacity which is
considerably higher than that of either the single antioxidants or
the single phosphate or phosphite additives. These stabilising
compositions can be used in all fields where the single components
of the mixtures are generally used and where deterioration due to
oxidation processes takes place.
Inventors: |
Holt, Alan; (Manchester,
GB) ; Mulqueen, Gerard; (Cheshire, GB) |
Correspondence
Address: |
Thomas Q Henry
Woodard Emhardt Naughton Moriarty & McNett
Bank One Tower Suite 3700
111 Monument Circle
Indianapolis
IN
46204
US
|
Family ID: |
9891265 |
Appl. No.: |
10/275368 |
Filed: |
November 5, 2002 |
PCT Filed: |
May 10, 2001 |
PCT NO: |
PCT/GB01/02058 |
Current U.S.
Class: |
508/438 ;
508/436; 508/442; 508/465; 508/563; 508/571; 508/572 |
Current CPC
Class: |
C10N 2040/20 20130101;
C10M 2223/04 20130101; C10M 141/10 20130101; C10M 133/12 20130101;
C10N 2040/04 20130101; C10N 2040/042 20200501; C10M 137/04
20130101; C10N 2040/25 20130101; C10N 2040/255 20200501; C10M
2215/06 20130101; C10N 2040/044 20200501; C10M 2215/066 20130101;
C10M 2223/041 20130101; C10N 2040/28 20130101; C10M 2219/087
20130101; C10M 2215/064 20130101; C10M 2219/084 20130101; C10N
2040/046 20200501; C10M 2223/02 20130101; C10M 2219/089 20130101;
C10N 2040/251 20200501; C10M 2215/067 20130101; C10N 2040/02
20130101; C10M 2215/068 20130101; C10M 2290/02 20130101; C10M
129/12 20130101; C10M 2207/289 20130101; C10M 2215/065 20130101;
C10M 2207/025 20130101; C10M 2207/024 20130101; C10M 2223/049
20130101; C10M 2223/10 20130101; C10N 2050/10 20130101; C10M
2207/288 20130101; C10M 137/02 20130101; C10M 2223/042 20130101;
C10M 135/30 20130101; C10M 129/76 20130101; C10M 135/24 20130101;
C10M 2219/088 20130101; C10N 2040/08 20130101; C10M 2207/287
20130101; C10M 2223/02 20130101; C10M 2223/02 20130101; C10M
2223/04 20130101; C10M 2223/04 20130101; C10M 2223/041 20130101;
C10M 2223/041 20130101; C10M 2223/049 20130101; C10M 2223/049
20130101; C10M 2223/10 20130101; C10M 2223/10 20130101 |
Class at
Publication: |
508/438 ;
508/436; 508/442; 508/465; 508/563; 508/571; 508/572 |
International
Class: |
C10M 141/10 |
Claims
1. A stabilising composition comprising a mixture of: (a) at least
one aromatic aminic antioxidant having the general formula: 13
wherein R.sub.1 and R.sub.2 are the same or different and may be H,
an alkyl group with 4 to 9 carbon atoms or an aralkyl group with 8
carbon atoms and m and n are 0 to 2 but m+n is not greater than 3,
either alone or optionally blended with at least one hindered
phenolic antioxidant selected from those corresponding to one of
the following general formulae: 14 wherein R.sub.3, R.sub.4,
R.sub.5 and R.sub.6 are the same or different and may be an alkyl
group with 1 to 4 carbon atoms and X is --S-- or --CH.sub.2-- or
--CH.sub.2CH.sub.2--S--CH.sub.2CH.sub.2-- or
--CH.sub.2--S--CH.sub.2-- or
--CH.sub.2CH.sub.2CO.sub.2CH.sub.2CH.sub.2---
S--CH.sub.2CH.sub.2CO.sub.2CH.sub.2CH.sub.2-- 15 wherein R.sub.7 is
an alkyl group with 6 to 20 carbon atoms; and 16 with (b) at least
one neutral organo phosphate or phosphite optionally mixed with at
least one acid organo phosphate or phosphite selected from those
corresponding to the following general formulae (i) neutral triaryl
phosphates: 17 wherein R.sub.8, R.sub.9 and R.sub.10 are the same
or different and may be H, CH.sub.3, isopropyl or tertiary butyl
and m is 0 to 2; (ii) neutral trialkyl phosphates: 18 wherein
R.sub.11, R.sub.12 and R.sub.13 are all the same and are alkyl
groups with 4 to 12 carbon atoms; (iii) neutral alkyl aryl
phosphates: 19 wherein R.sub.14 is different from R.sub.15 and
R.sub.16 and R.sub.14 is an alkyl group with 4 to 12 carbon atoms
and R.sub.15 is phenyl or substituted phenyl with 7 to 10 carbon
atoms and R.sub.16 may be an alkyl group with 4 to 12 carbon atoms
or phenyl or substituted phenyl with 7 to 10 carbon atoms; (iv)
alkyl acid phosphates: 20 wherein R.sub.17 is an alkyl group with 5
to 12 carbon atoms and m is 1 or 2 and n is 1 or 2 but m+n is not
greater than 3; (v) neutral triaryl phosphites: 21 wherein
R.sub.18, R.sub.19, R.sub.20 are the same or different and are H or
alkyl with 1 to 9 carbon atoms. (vi) neutral trialkyl phosphites 22
wherein R.sub.21, R.sub.22, and R.sub.23 are the same or different
and are alkyl groups with 1 to 18 carbon atoms. (vii) neutral alkyl
aryl phosphites: 23 wherein R.sub.24 and R.sub.25 are the same or
different and are alkyl groups with 1 to 12 carbon atoms or
R.sub.24 is phenyl or substituted phenyl where R26 is alkyl with 1
to 9 carbon atoms. (viii) alkyl acid phosphites: 24 wherein
R.sub.27 may be an alkyl group with 4 to 18 carbon atoms, phenyl or
substituted phenyl with 7 to 10 carbon atoms and m is 1 or 2, n is
1 or 2 but m+n is not greater than 3, and wherein the antioxidants
and the phosphate(s) and/or phosphite(s) are utilised in a weight
ratio from 10:1 to 1:10.
2. The stabilising composition in accordance with claim 1 wherein
the antioxidant(s) and the phosphate(s) and/or phosphite(s) are
utilised in a weight ratio from 1:1 to 1:5.
3. The stabilising composition in accordance with claim 1 or claim
2 which has been prepared by heating the antioxidant(s) and the
phosphate(s) and/or phosphite(s) for 0.2 to 6 hours at a
temperature between 40.degree. C. and 150.degree. C.
4. A lubricant base stock or lubricant composition stabilised by
the stabilised composition of any one of claims 1 to 3.
Description
[0001] This invention relates to stabilising compositions for
lubricant base stocks and lubricant formulations.
[0002] We have unexpectedly found that mixtures of certain aromatic
aminic antioxidants, optionally in admixture with certain hindered
phenol antioxidants, when mixed with certain organo phosphate
esters and organo phosphite esters offer unique synergy and
improved performance in terms of stability when used within
lubricant base stocks and lubricant formulations.
[0003] By lubricant base stocks is meant lubricants such as mineral
and synthetic base oils chosen from Group I, Group II, Group III,
Group IV and Group V base stocks as classified by the American
Petroleum Institute, as well as natural and synthetic esters
including polyol esters, more particularly, but not limited to
automotive oils, circulatory oils, gear oils, greases, hydraulic
fluids, turbine fluids and metal working fluids.
[0004] By lubricant formulations, is meant a lubricant base stock
as described above, plus additional additives including but not
limited to antioxidants, rust inhibitors, metal passivators,
ashless dispersants, antiwear additives, extreme pressure additives
and detergents, viscosity index improvers and antifoam agents.
[0005] According to the present invention a stabilising composition
for lubricant base stocks and lubricant compositions comprises:
[0006] (a) at least one aromatic aminic antioxidant having the
general formula: 1
[0007] wherein R.sup.1 and R.sub.2 are the same or different and
may be H, an alkyl group with 4 to 9 carbon atoms or an aralkyl
group with 8 carbon atoms and m and n are 0 to 2 but m+n is not
greater than 3, either alone or optionally blended with at least
one hindered phenolic antioxidant selected from those corresponding
to one of the following general formulae: 2
[0008] wherein R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are the same
or different and may be an alkyl group with 1 to 4 carbon atoms and
X is --S-- or --CH.sub.2-- or
--CH.sub.2CH.sub.2--S--CH.sub.2CH.sub.2-- or
--CH.sub.2--S--CH.sub.2-- or
--CH.sub.2CH.sub.2CO.sub.2CH.sub.2CH.sub.2---
S--CH.sub.2CH.sub.2CO.sub.2CH.sub.2CH.sub.2-- 3
[0009] wherein R.sub.7 is an alkyl group with 6 to 20 carbon atoms;
and 4
[0010] with (b) at least one neutral organo phosphate or phosphite
optionally mixed with at least one acid organo phosphate or
phosphite selected from those corresponding to the following
general formulae:
[0011] (i) neutral triaryl phosphates: 5
[0012] wherein R.sub.8, R.sub.9 and R.sub.10 are the same or
different and may be H, CH.sub.3, isopropyl or tertiary butyl and m
is 0 to 2;
[0013] (ii) neutral trialkyl phosphates: 6
[0014] wherein R.sub.11, R.sub.12 and R.sub.13 are all the same and
are alkyl groups with 4 to 12 carbon atoms;
[0015] (iii) neutral alkyl aryl phosphates: 7
[0016] wherein R.sub.14 is different from R.sub.15 and R.sub.16 and
R.sub.14 is an alkyl group with 4 to 12 carbon atoms and R.sub.15
is phenyl or substituted phenyl with 7 to 10 carbon atoms and
R.sub.16 may be an alkyl group with 4 to 12 carbon atoms or phenyl
or substituted phenyl with 7 to 10 carbon atoms;
[0017] (iv) alkyl acid phosphates: 8
[0018] wherein R.sub.17 is an alkyl group with 5 to 12 carbon atoms
and m is 1 or 2 and n is 1 or 2 but m+n is not greater than 3;
[0019] (v) neutral triaryl phosphites: 9
[0020] wherein R.sub.18, R.sub.19, R.sub.20 are the same or
different and are H or alkyl with 1 to 9 carbon atoms;
[0021] (vi) neutral trialkyl phosphites: 10
[0022] wherein R.sub.21, R.sub.22 and R.sub.23 are the same or
different and are alkyl groups with 1 to 18 carbon atoms.
[0023] (vii) neutral alkyl aryl phosphites: 11
[0024] wherein R.sub.24 and R.sub.25 are the same or different and
are alkyl groups with 1 to 12 carbon atoms or R.sub.24 is phenyl or
substituted phenyl where R.sub.26 is alkyl with 1 to 9 carbon
atoms.
[0025] (viii) alkyl acid phosphites: 12
[0026] wherein R.sub.27 may be an alkyl group with 4 to 18 carbon
atoms, phenyl or substituted phenyl with 7 to 10 carbon atoms and m
is 1 or 2, m is 1 or 2 but m+n is not greater than 3, and wherein
the antioxidants and the phosphate(s) and/or phosphite(s) are
utilised in a weight ratio from 10:1 to 1:10, preferably 1:1 to
1:5.
[0027] In one embodiment of the invention, the stabilising
composition is prepared by heating the antioxidant(s) and the
phosphate(s) and/or phosphite(s) for 0.2 to 6 hours at a
temperature range of 40.degree. C. to 150.degree. C.
[0028] The treat rates of the antioxidant(s) and the phosphate(s)
and/or phosphite(s) in the lubricant base stocks and lubricant
compositions preferably are within the following weight ranges:
[0029] (a) aromatic amine antioxidants--0.1 to 5%;
[0030] (b) hindered phenol antioxidants--0.1 to 5%;
[0031] (c) neutral aryl phosphates--0.2 to 10%;
[0032] (d) neutral alkyl phosphates--0.2 to 10%;
[0033] (e) neutral alkyl aryl phosphates--0.2 to 10%;
[0034] (i) alkyl acid phosphates--0.01 to 5%;
[0035] (g) neutral aryl phosphites--0.2 to 10%;
[0036] (h) neutral alkyl phosphites--0.2 to 10%;
[0037] (i) neutral alkyl aryl phosphites--0.2 to 10%;
[0038] (j) alkyl acid phosphites--0.01 to 5%;
[0039] Preferably, the amine and hindered phenol antioxidants are
used at 0.5 to 2.0% each. The neutral alkyl, aryl and alkyl aryl
phosphates and phosphites are used at 0.5 to 4%. The acid
phosphates and phosphites at 0.025 to 0.05% (when used together
with the neutral phosphates).
[0040] Examples of formula I compounds are 4-tert-butyl,
4'-tert-octyl diphenylamine; 4,4'-di-tert-octyl diphenyl amine and
4,4'-di-iso-nonyl diphenylamine.
[0041] Examples of formula II compounds are 4,4'-methylene bis (2,6
ditertiary butyl phenol); 2,2' thiodiethylene
bis[3-(3,5-di-tert-butyl-4-- hydroxy-phenyl) propionate];
4,4'-thiobis(2-t-butyl-5-methyl phenol); 6,6'-thiobis
(2-methyl-4-t-butylphenol).
[0042] Examples of fonmula III compounds are C.sub.7-9 alkyl ester
of 3,5-di-tert-butyl-4-hydroxy benzene-3-propionic acid;
C.sub.14-16 alkyl ester of 3,5-di-tert-butyl-4-hydroxy
benzene-3-propionic acid.
[0043] An Example of formula IV compounds is pentaerythritol tetra
ester of 3,5 di-tert-butyl-4-hydroxy benzene-3-propionic acid.
[0044] Examples of formula V compounds are tri-dimethyl phenyl
phosphate; tri-isopropyl phenyl phosphate; mono-phenyl-di
(-tert-butyl phenyl) phosphate.
[0045] Examples of formula VI compounds are tributyl phosphate;
trioctyl phosphate.
[0046] Examples of formula VII compounds are octyldiphenyl
phosphate; dibutyl-mono-phenyl phosphate.
[0047] Examples of formula VIII compounds are dipentyl hydrogen
phosphate; di C.sub.10-12 alkyl-hydrogen phosphate; C.sub.10-12
alkyl-dihydrogen phosphate.
[0048] An Example of formula IX is tris nonyl phenyl phosphite.
[0049] Examples of formula X are trilauryl phosphite; trioctyl
phosphite.
[0050] Examples of formula XI are decyl diphenyl phosphite; didecyl
monophenyl phosphite.
[0051] Examples of formula XII are dibutyl hydrogen phosphite;
dioctyl hydrogen phosphite; cetyl stearyl hydrogen phosphite.
[0052] Using stabilising compositions of the invention, lubricant
base stocks and lubricant formulations can have varying levels of
stability dependent on:
[0053] (i) proper choice of the antioxidant(s) and phosphate(s)
and/or phosphite(s) to provide for the best performance, in tenns
of stability, within particular lubricant base stocks or particular
lubricant formulations; or
[0054] (ii) by changing the ratio of the antioxidant to the
phosphate(s) and/or phosphite(s); or
[0055] (iii) keeping the ratio of the antioxidant(s) to the
phosphate(s) and/or pbosphite(s) constant while altering or
decreasing the treat rate of the antioxidant(s) and phosphate(s)
and/or phosphite(s).
[0056] (iv) changing the ratio of neutral phosphate to acid
phosphate and neutral phosphite to acid phosphite.
[0057] In other words, the components of the mixtures of the
invention, either individually or in combination, can be tailored
to provide the required performance characteristics in terms of
stability, in a particular base stock and/or lubricant
formulation.
[0058] Embodiments of the invention will now be described by way of
example with reference to the Table set out below.
[0059] The Table shows the relative oxidation stability results
obtained by adding certain antioxidant(s) and phosphate(s) and/or
phosphite(s) mixtures to Group III base stocks. The relative
oxidation stabilities of the lubricant base stock is determined by
the rotating bomb oxidation stability test (RBOT), IP test method
number 229. The oxidation stability is defined as the number of
minutes required to effect a reduction in oxygen pressure of 25.4
PSI or 1.75 bar when the oil and additives are heated at
150.degree. C. in an oxygen pressurised vessel.
[0060] The results in the Table show that there is a synergistic
effect (in terms of stability) when a blend of additives according
to the invention is added to Group III lubricant base stocks.
1 ASTM IP 229 ROTARY BOMB OXIDATION TEST DATA Conc Conc RBOT LIFE
BASE OIL (%) ANTIOXIDANT (%) PHOSPHATE ESTER (mins) Group III
Mineral oil 25 " 1.0 Neutral Tri Aryl Phosphate (Isopropylated
phenyl phosphate) 40 " 1.0 Neutral Tri Aryl Phosphate (Tertiary
Butylated phenyl phosphate) 22 " 1.0 Neutral Tri Alkyl Phosphate
(Tri Octyl phosphate)) 17 " 1.0 Alkyl Aryl Phosphate (Octyl
diphenyl phosphate) 30 " 1.0 Alkyl Aryl Phosphate (Iso decyl
diphenyl phosphate) 25 " 1.0 Acid Alkyl Phosphate (C10-C12) 18 "
0.05 Acid Alkyl Phosphate (C10-C12) 21 " 1.0 95:5 Neutral Tri Aryl
Phosphate (Isopropylated phenyl 20 phosphate) + Acid Alkyl
phosphate (C10-C12) " 0.5 Butyl/Octyl diphenylamine 1088 0.5
Butyl/Octyl diphenylamine 1.0 Neutral Tri Aryl Phosphate
(Isopropylated phenyl phosphate) 1250 " 0.5 Butyl/Octyl
diphenylamine 1.0 Neutral Tri Aryl Phosphate (Tertiary Butylated
phenyl phosphate) 1430 " 0.5 Butyl/Octyl diphenylamine 1.0 Neutral
Tri Alkyl Phosphate (Tri Octyl phosphate) 1795 " 0.5 Butyl/Octyl
diphenylamine 1.0 Acid Alkyl phosphate (C10-C12) 880 " 0.5
Butyl/Octyl diphenylamine 1.0 3:1 Neutral Tri Aryl Phosphate
(Isopropylated phenyl phosphate) + 1415 Acid Alkyl phosphate
(C10-C12) " 0.5 Butyl/Octyl diphenylamine 1.0 9:1 Neutral Tri Aryl
Phosphate (Isopropylated phenyl phosphate) + 1811 Acid Alkyl
phosphate (C10-C12) " 0.5 Butyl/Octyl diphenylamine 1.0 95:5
Neutral Tri Aryl Phosphate (Isopropylated phenyl phosphate) + 2068
Acid Alkyl phosphate (C10-C12) " 0.5 Butyl/Octyl diphenylamine 1.0
95:5 Alkyl Aryl Phosphate (Octyl diphenyl phosphate) + Acid 1967
Alkyl phosphate (C10-C12) " 0.5 Butyl/Octyl diphenylamine 1.0 95:5
Alkyl Aryl Phosphate (Iso decyl diphenyl phosphate) + Acid 1915
Alkyl phosphate (C10-C12) " 0.5 Di Nonyl diphenylamine 640 " 0.5 Di
Nonyl diphenylamine 1.0 Neutral (Isopropylated phenyl phosphate) +
Acid 833 Alkyl phosphate (C10-C12) 95:5 " 0.5 1:4 High molecular
weight 730 phenolic (Form 4) + Butyl/Octyl diphenylamine " 0.5 1:4
High molecular weight 1.0 95:5 Neutral Tri Aryl Phosphate
(Isopropylated phenyl phosphate) 1537 phenolic (Form 4) + Tri Aryl
Phosphate + Acid Alkyl phosphate (C10-C12) Butyl/Octyl
diphenylamine " 0.5 15:15:70 Sulphur 372 containing phenolic (Form
2) + High molecular weight phenolic (Form 4) + Butyl/Octyl
diphenylamine " 0.5 15:15:70 Sulphur contain- 1.0 95:5 Neutral Tri
Aryl Phosphate (Isopropylated phenyl phosphate) + 646 ing phenolic
(Form 2) + Acid Alkyl phosphate (C10-C12) High molecular weight
phenolic (Form 4) + Butyl/Octyl diphenylamine " 0.5 1:4 Sulphur
containing 355 phenolic (Form 2) + Otcyl/Styryl diphenylamine " 0.5
1:4 Sulphur containing 1.0 95:5 Neutral Tri Aryl Phosphate
(Isopropylated phenyl phosphate) + 908 phenolic (Form 2) + Acid
Alkyl phosphate (C10-C12) 4-Octyl/Styryl diphenylamine " 0.5 1:4
Sulphur containing 365 phenolic (Form 2) + Butyl/Octyl
diphenylamine " 0.5 1:4 Sulphur containing 1.0 95:5 Neutral Tri
Aryl Phosphate 755 phenolic (Form 2) + (Isopropylated phenyl
phosphate) + Butyl/Octyl diphenylamine Acid Alkyl phosphate
(C10-C12)
* * * * *