U.S. patent application number 15/522961 was filed with the patent office on 2017-11-02 for compositions comprising an alternative to di-isotridecyl adipate.
The applicant listed for this patent is OLEON NV. Invention is credited to Matthieu CHATILLON, Maarten GHYSEL, Lieven VAN HECKE, Ben VERHAEGHE.
Application Number | 20170313953 15/522961 |
Document ID | / |
Family ID | 52465517 |
Filed Date | 2017-11-02 |
United States Patent
Application |
20170313953 |
Kind Code |
A1 |
VAN HECKE; Lieven ; et
al. |
November 2, 2017 |
COMPOSITIONS COMPRISING AN ALTERNATIVE TO DI-ISOTRIDECYL
ADIPATE
Abstract
The present invention concerns compositions, and more
specifically lubricating compositions, comprising an alternative to
di-iso tridecyl adipate (DITA). The present invention therefore
discloses compositions comprising di-(2-hexyldecyl) succinate,
advantageously from a renewable source, and the uses thereof as
lubricating compositions, in particular as hydraulic oils or engine
oils.
Inventors: |
VAN HECKE; Lieven;
(Antwerpen, BE) ; CHATILLON; Matthieu; (Compiegne,
FR) ; VERHAEGHE; Ben; (Rijkevorsel, BE) ;
GHYSEL; Maarten; (Roeselare, BE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
OLEON NV |
Evergem (Ertvelde) |
|
BE |
|
|
Family ID: |
52465517 |
Appl. No.: |
15/522961 |
Filed: |
October 28, 2015 |
PCT Filed: |
October 28, 2015 |
PCT NO: |
PCT/FR2015/052908 |
371 Date: |
April 28, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10M 2215/064 20130101;
C10M 2207/401 20130101; C10N 2030/02 20130101; C10M 2207/2835
20130101; C10N 2070/00 20130101; C10M 2205/0285 20130101; C10N
2030/26 20200501; C10N 2030/12 20130101; C10M 2203/1025 20130101;
C10N 2030/10 20130101; C10N 2040/08 20130101; C10N 2040/04
20130101; C10N 2030/36 20200501; C10M 2215/04 20130101; C10M 105/36
20130101; C10M 2229/02 20130101; C10M 2207/026 20130101; C10N
2040/25 20130101; C10N 2030/64 20200501; C10M 2215/223 20130101;
C10M 2207/2825 20130101; C10N 2040/20 20130101; C10M 169/04
20130101; C10N 2030/08 20130101 |
International
Class: |
C10M 105/36 20060101
C10M105/36 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 29, 2014 |
FR |
1460395 |
Claims
1. A composition comprising: di-(2-hexyldecyl) succinate, and an
antioxidant for lubricants and/or an anti-wear agent for
lubricants.
2. A process for the preparation of the composition according to
claim 1, comprising a step of mixing di-(2-hexyldecyl) succinate
with the antioxidant and/or the anti-wear agent.
3. A method of lubricating an engine comprising applying an engine
oil comprising the composition according to claim 1 to an
engine.
4. Engine oil comprising a composition according to claim 1.
5. Hydraulic oil comprising a composition according to claim 1.
6. Gear oil comprising a composition according to claim 1.
7. Metalworking oil comprising a composition according to claim
1.
8. A process for improving the lubricating power and/or the
hydrolytic stability and/or the oxidation stability and/or the
compatibility with elastomers and/or the solvent power of a
composition, comprising introducing di-(2-hexyldecyl) succinate
into the composition.
9. (canceled)
10. A composition consisting of di-(2-hexyldecyl) succinate and a
base oil.
11. (canceled)
12. The composition according to claim 1, wherein the
di-(2-hexyldecyl) succinate comprises at least 90% carbon of
renewable origin.
13. (canceled)
14. (canceled)
15. The engine oil according to claim 4, wherein the
di-(2-hexyldecyl) succinate comprises at least 90% carbon of
renewable origin.
16. The hydraulic oil according to claim 5, wherein the
di-(2-hexyldecyl) succinate comprises at least 90% carbon of
renewable origin.
17. The gear oil according to claim 6, wherein the
di-(2-hexyldecyl) succinate comprises at least 90% carbon of
renewable origin.
18. The metalworking oil according to claim 7, wherein the
di-(2-hexyldecyl) succinate comprises at least 90% carbon of
renewable origin.
19. The composition according to claim 10, wherein the
di-(2-hexyldecyl) succinate comprises at least 90% carbon of
renewable origin.
Description
[0001] The present invention relates to compositions comprising a
specific diester, as well as to uses thereof, for example as
lubricant compositions, in particular as hydraulic oils or engine
oils. The invention also relates to processes for the preparation
thereof.
[0002] A lubricant composition generally comprises a base oil and
one or more additive(s).
[0003] A base oil is usually the majority constituent (i.e. the
constituent the content of which is the highest) of a lubricant
composition. A base oil is constituted by one or more oil(s)
selected from:
[0004] mineral oils,
[0005] natural oils, and/or
[0006] synthetic oils.
[0007] Mineral oils are oils originating from oil refining. They
are essentially constituted by carbon and hydrogen atoms, such as
paraffinic oils, hydrorefined oils, hydrocracked oils and
hydroisomerized oils.
[0008] By natural oils, is meant more particularly vegetable oils,
animal oils or those originating from algae.
[0009] The synthetic oils are obtained by chemical reaction between
molecules of petrochemical origin and/or renewable origin, with the
exception of usual chemical reactions making it possible to obtain
mineral oils (such as hydrorefining, hydrocracking,
hydroisomerization, etc.). Among the different families of
synthetic oil, there may be mentioned in particular esters,
polyalkylene glycols (PAG) and polyalphaolefins (PAO).
[0010] Preferably, the oil or oils for the base oil is/are selected
from the group constituted by mineral oils and synthetic oils.
[0011] Preferentially, the oil comprises between 15 and 80 carbon
atoms, preferentially between 18 and 65 carbon atoms.
[0012] It will be noted that, within the context of the present
application, and unless stated otherwise, the ranges of values
indicated are understood to be inclusive.
[0013] In particular, the oil has a boiling-point temperature
comprised between 250 and 900.degree. C., more preferentially
between 280 and 870.degree. C., even more preferentially between
310 and 855.degree. C. (under normal pressure conditions).
[0014] A lubricant composition has many functions, such as reducing
friction between surfaces, protection against wear, heat transfer,
energy transmission, corrosion prevention. Depending on the
function(s) envisaged for the composition, the latter must have
specific properties.
[0015] Now, the base oil generally represents between 50 and 99.9%,
preferentially between 70% and 99% by weight of this composition.
Thus, the properties of the lubricant composition are dependent on
the properties of the base oil.
[0016] As indicated above, apart from the base oil, a lubricant
composition contains at least one additive. This additive is
generally used in order to reinforce one or more intrinsic property
or properties of the base oil and/or to provide one or more
additional property or properties.
[0017] Among the additives usually used in the field of lubricants,
there may be mentioned in particular antioxidants, anti-wear
agents, viscosity index improvers, friction modifiers,
extreme-pressure modifiers, pour point depressants, anti-foam
agents, de-emulsifiers, anti-corrosion or anti-rust agents,
thickeners, detergents and dispersants.
[0018] The applicant has taken a particular interest in lubricant
compositions employed in particularly demanding utilizations, such
as hydraulic oils and engine oils, requiring high-performance
lubrication and a degree of longevity. These compositions must
comply with strict specifications, like having properties such as
good lubricating power, a given viscosity range, good hydrolytic
stability, good oxidation stability, good low-temperature
stability, good compatibility with elastomers and/or good solvent
power.
[0019] The lubricating power of a composition or an oil is its
ability to reduce friction (rubbing or deformation between moving
parts) and/or to reduce wear of the parts.
[0020] The reduction in friction can be measured using a device of
the ball-on-flat type, for which the frictional force is measured
as a function of different contact parameters, such as a Mini
Traction Machine (MTM) device.
[0021] The reduction in wear can be measured by the 4-ball
test.
[0022] The choice of the viscosity of the composition and thus of
the base oil, is very important for the efficiency of the
lubrication.
[0023] The viscosity is generally assessed using a viscosity index
and by measuring the kinematic viscosity at at least a given
temperature. These measures are well known to a person skilled in
the art. For example, the viscosity index can be measured according
to the standard ASTM D 2270 and the kinematic viscosity can be
assessed according to the standard ASTM D 445 which is equivalent
to the standard ISO 3104.
[0024] Throughout the present application, the standards are those
current at the filing date of the application.
[0025] The hydrolytic stability is the ability of a composition or
an oil to remain stable in the presence of water, i.e. not to
become hydrolyzed. This stability can be assessed by means of
measuring the difference in acid value, the variation in the
kinematic viscosity and/or the variation in the weight of the
copper plate, following the presence of water. By way of example,
the hydrolytic stability can be measured according to the standard
ASTM D 2619.
[0026] Oxidation stability is the ability of a composition or an
oil to resist oxidation, in the presence of oxygen, and possibly
following a temperature increase. This stability can be measured
according to the standard ASTM D 2272.
[0027] The low-temperature stability of a composition or an oil is
the ability thereof to withstand low temperatures. The
low-temperature stability can be assessed by measuring the pour
point of a composition or an oil. Measurement of the pour point can
be carried out according to the standard ASTM D 97.
[0028] The compatibility with elastomers of a composition or an oil
is the ability thereof, in particular, not to cause swelling of the
elastomer when the latter is in contact with the composition or the
oil. By elastomer, is meant in particular acrylonitrile butadiene
rubber, hydrogenated nitrile butadiene rubber and/or fluorinated
rubber. This swelling, or volume difference, can be measured
according to the standard ISO 1817. The compatibility with
elastomers can also relate to the ability of a composition or an
oil not to cause variations in the hardness of the elastomer and
not to affect the tensile strength and/or the elongation at break
of the elastomer. This compatibility is important because
elastomers are frequently present in the envisaged applications. By
way of example, the materials constituting the seals for engines
and transmissions are made from elastomer.
[0029] By solvent power of a composition or an oil is meant more
particularly the solubilization of the additives and/or any
degradation products originating from oxidation of other compounds
in the presence of the composition or the oil.
[0030] A synthetic oil, particularly suitable due to its properties
for a use such as in hydraulic oils or engine oils, is available on
the market. This is di-isotridecyl adipate (DITA), described in
U.S. Pat. No. 3,481,873 published in 1969, which contains a large
number of the aforementioned properties.
[0031] In fact, DITA has: [0032] a kinematic viscosity at
40.degree. C. of 27.3 mm.sup.2/s and a kinematic viscosity at
100.degree. C. of 5.3 mm.sup.2/s, measured according to the
standard ASTM D 445, [0033] good hydrolytic stability
characterized, according to the standard ASTM D 2619, by a small
difference in acid value (0.08 mg KOH/g), a small kinematic
viscosity variation at 40.degree. C. (0.8%) and a small variation
in the weight of the copper plate (0.05 mg/cm.sup.2), [0034] good
oxidation stability, [0035] good low-temperature stability linked
to the low pour point of -64.degree. C., measured according to the
standard ASTM D 97, and [0036] good compatibility with elastomers
selected from acrylonitrile-butadiene rubber, such as NBR 1,
hydrogenated nitrile butadiene rubber, such as HNBR 1, fluorinated
rubber, such as FKM 2.
[0037] NBR 1 is an elastomer based on acrylonitrile butadiene
rubber with an acrylic nitrile content of 28% by weight based on
the total weight of rubber.
[0038] FKM 2 is an elastomer based on fluorinated rubber. It is
more particularly constituted by vinylidene fluoride,
hexafluoropropylene and tetrafluoroethylene and has a fluorine
content comprised between 68 and 69% by weight based on the total
weight of rubber.
[0039] HNBR 1 is an elastomer based on hydrogenated
acrylonitrile-butadiene rubber with an acrylonitrile content of 35%
based on the total weight of rubber.
[0040] All these properties make DITA a synthetic oil of choice
used in hydraulic oils and/or engine oils. This explains that the
worldwide consumption of DITA is estimated today at over 10,000
tonnes annually. However, the toxicity of DITA is currently open to
question since DITA is listed in the "Community Rolling Action
Plan" of the ECHA (European CHemical Agency) intended to assess
substances from a toxicological and ecotoxicological point of
view.
[0041] Although DITA is a relatively long-established product, and
despite numerous attempts towards the substitution of DITA, no
molecule combining all the properties of DITA has to date been
identified, allowing DITA to be replaced.
[0042] In order to replace DITA, the molecule must fulfil the
following specifications (set of properties to be satisfied):
[0043] good viscosity and in particular a kinematic viscosity at
40.degree. C. comprised between 24 and 29 mm.sup.2/s, a kinematic
viscosity at 100.degree. C. comprised between 5.00 and 5.54
mm.sup.2/s, measured according to the standard ASTM D 445, [0044]
good hydrolytic stability, [0045] good oxidation stability, [0046]
good low-temperature stability, in particular with a pour point
less than -45.degree. C., measured according to the standard ASTM D
97, and [0047] good compatibility with the elastomers selected from
acrylonitrile butadiene rubber, such as NBR 1, hydrogenated
acrylonitrile-butadiene rubber, such as HNBR 1, fluorinated rubber,
such as FKM 2.
[0048] Therefore there is still a need for a molecule comprising
most of the properties of DITA, that is more environmentally
friendly (plant or animal) and accessible by means of an
economically acceptable process.
[0049] The molecule identified by the inventors responds to this
need. The work of the inventors has in fact made it possible to
demonstrate that a specific diester combined not only most of the
properties of DITA, but also superseded DITA for some of its
properties. In addition, this diester can also be prepared from
renewable resources and is therefore more environmentally friendly.
It can therefore advantageously replace DITA. This diester is
di-(2-hexyldecyl) succinate (also known by the abbreviation DHDS),
shown in FIG. 1.
[0050] Di-(2-hexyldecyl) succinate was described in the application
WO2005/014764 as being capable of forming part of the composition
of an emulsion in order to lubricate conveyor chains in the
agri-food sector. The purpose of this composition is to be able to
reduce friction by forming a film over the conveyor chain, which
can be easily washable. These conveyor chains must in fact be
capable of being cleaned frequently in order to comply with the
hygiene conditions required in the agri-food sector. For this
reason, the lubricant composition is presented in this case in the
form of emulsion, which allows easier washing with water.
Hydrolytic stability, oxidation stability, low-temperature
stability and longevity are therefore not properties that are
sought for this composition, because these are not necessary for
lubrication that is repeated over a short period of time. For
example, the emulsion disclosed in WO2005/014764 is applied every
10 minutes to be conveyor chains.
[0051] Such an emulsion is not suitable for use as an engine oil or
hydraulic oil. On the one hand, the presence of a large quantity of
water in a hydraulic oil or motor oil is to be avoided. On the
other hand, in such uses, the compositions or oils are utilized
over long periods of time that may extend over at least several
months, requiring properties of stability, in particular in the
presence of water and air. In particular, it is important to have a
composition or an oil that is hydrolytically stable.
[0052] As indicated above, DHDS thus has properties that are
equivalent to those of DITA. Some are even improved, namely the
hydrolytic stability and the compatibility with elastomers.
[0053] In particular, DHDS has: [0054] good viscosity and in
particular a kinematic viscosity at 40.degree. C. of 27.3
mm.sup.2/s, a kinematic viscosity at 100.degree. C. of 5.37
mm.sup.2/s, measured according to the standard ASTM D 445, [0055]
good hydrolytic stability, measured according to the standard ASTM
D 2619, demonstrated in particular by a small difference in acid
value (0.06 mg KOH/g), a low kinematic viscosity variation at
40.degree. C. (-0.4%) and a small variation in the weight of the
copper plate (0.05 mg/cm.sup.2), [0056] good oxidation stability,
[0057] good low-temperature stability, in particular with a pour
point equal to -64.degree. C., measured according to the standard
ASTM D 97, and [0058] good compatibility with the elastomers
selected from acrylonitrile butadiene rubber, such as NBR 1,
hydrogenated acrylonitrile-butadiene rubber, such as HNBR 1,
fluorinated rubber, such as FKM 2.
[0059] DHDS thus fully corresponds to the specifications.
[0060] For further details, the properties of DITA and DHDS are
grouped together and compared in the Table 1 of Example 2
hereinafter.
[0061] It will be noted that for the hydrolytic stability, the
difference in acid value and the viscosity variation are lower for
DHDS than for DITA, demonstrating the better hydrolytic stability
of DHDS.
[0062] As regards the low-temperature stability, the pour point of
DHDS is less than that of DITA, which demonstrates a better
low-temperature stability.
[0063] As regards the compatibility with elastomers, the volume
difference (or swelling) observed for DHDS is 6.8% with the NBR 1,
whereas it is 15% with DITA under the same conditions. The volume
difference observed for DHDS is 4.4% with the HNBR 1, whereas it is
11.2% with DITA under the same conditions. No variation in volume
was observed for DHDS with the FKM 2, whereas a variation in volume
of 0.5% was observed with DITA under the same conditions. DHDS thus
has a better compatibility with elastomers than DITA.
[0064] DHDS is therefore an excellent alternative to DITA and can
thus advantageously be used in compositions in which the hydrolytic
stability, the low-temperature stability and/or the compatibility
with elastomers are of prime importance.
[0065] The present invention thus relates to specific compositions
containing DHDS, in particular lubricant compositions such as those
utilized under demanding conditions of use.
[0066] According to a first aspect of the invention, the present
invention discloses a composition containing: [0067]
di-(2-hexyldecyl) succinate, and [0068] an antioxidant and/or an
anti-wear agent.
[0069] The antioxidants and/or the anti-wear agents are in fact
among the main additives used in the lubricant compositions
utilized under demanding conditions of use. It will be noted more
particularly that these lubricant compositions, which are oily
compositions, are generally intended to have a certain longevity,
of at least a few months. By oily composition, is meant a
composition that does not contain water (such as, for example, a
water content less than 5000 ppm, preferentially less than or equal
to 1000 ppm).
[0070] More particularly, the invention relates to a composition
comprising: [0071] di-(2-hexyldecyl) succinate, and [0072] an
antioxidant for lubricants and/or an anti-wear agent for
lubricants.
[0073] The antioxidant makes it possible to slow, or even to
eliminate, oxidation of the product with which it is in a mixture.
In a composition comprising di-(2-hexyldecyl) succinate, the
antioxidant will improve the oxidation stability of the composition
containing di-(2-hexyldecyl) succinate, even if the latter is
already good due to the presence of DHDS, which has good oxidation
stability.
[0074] The antioxidant of the composition according to the
invention is thus an antioxidant used in the field of lubricants. A
person skilled in the art knows how to select the most suitable
antioxidant(s) according to the lubricating application. By way of
example, reference may be made to the following manuals: "Fuels and
Lubricants Handbook: technology, properties performance and
testing", by George E. Totten, 2003 and "Handbook of lubrication
and tribology, vol II: Theory and Design", by Robert W. Bruce,
2012.
[0075] The antioxidant is preferably selected from the group
constituted by saturated organic monosulphides; organic
polysulphides, such as dialkyl disulphides and dialkyl
trisulphides; sulphurized olefins (SO); dithiocarbamic acid
derivatives, such as dithiocarbamates; sulphurized phenols, such as
sulphurized alkylphenols (SAP); (alkyl or aryl) phosphites such as
tributyl phosphate and triaryl phosphites; dithiophosphoric acid
derivatives, such as dithiophosphates and dialkyldithiophosphates,
for example zinc dialkyldithiophosphates (ZDTP); hindered
substituted phenols, such as 2,6-di-t-butyl-4-methylphenol (BHT),
4,4'-methylenebis(2,6-di-tert-butylphenol) (MBDTBP) or
dibutylparacresol (DBPC), 3,5-di-tert-butyl-4-hydroxyhydrocinnamate
(ABHHC) optionally alkylated,
4,4'-thiobis(2-methyl-6-tert-butylphenol) and
2,6-di-tert-butylphenol (DTBP); sulphurized hindered phenols (SHP);
arylamines or aromatic amines, such as mono and dialkyl
diphenylamines (DPA) like dioctyldiphenylamine, optionally
alkylated N-phenyl-1-naphthylamines (PANA), phenothiazines and
alkylated derivatives thereof, tetramethyldiaminophenylmethane and
N,N'-disecbutyl-p-phenylenediamine; and mixtures thereof.
[0076] By hindered substituted phenols is meant a phenol comprising
at least one bulky group, such as a tert-butyl, at ortho position
of the hydroxyl group of the phenol, preferentially at both ortho
positions of the hydroxyl group, exerting steric hindrance
thereon.
[0077] Advantageously, the antioxidant can be selected from dialkyl
dithiophosphates, substituted phenols, aromatic amines or mixtures
thereof.
[0078] Alternatively, the antioxidant is selected from zinc dialkyl
dithiophosphates, sulphurized phenols, aromatic amines or mixtures
thereof.
[0079] The anti-wear agent makes it possible to reinforce the
anti-wear action performed by the oil vis-a-vis the elements
lubricated thereby. The anti-wear agent is therefore an anti-wear
agent used in the field of lubricants. A person skilled in the art
will know how to select the most suitable anti-wear agent(s)
according to the lubricating application. By way of example,
reference may be made to the following manuals: "Fuels and
Lubricants Handbook: technology, properties performance and
testing", published by George E. Totten, 2003 and "Handbook of
lubrication and tribology, vol II: Theory and Design", published by
Robert W. Bruce, 2012. It is preferably selected from the group
constituted by saturated organic monosulphides; organic
polysulphides, such as dialkyl disulphides and dialkyl
trisulphides; sulphurized olefins; dithiocarbamic acid derivatives,
such as dithiocarbamates, such as zinc dithiocarbamates; (alkyl or
aryl) phosphites, such as dialkyl hydrogen phosphites and
triaryl-phosphites; dithiophosphoric acid derivatives, such as
dithiophosphates and dialkyldithiophosphates such as zinc
dialkyldithiophosphates (ZDTP); arylphosphates, such as
tricresylphosphates (TCP); amine phosphates; chlorinated compounds,
such as chlorowaxes; potassium triborate; compounds containing
molybdenum; and mixtures thereof.
[0080] Advantageously, the anti-wear agent can be selected from
zinc dialkyl dithiophosphates, phosphorus-containing derivatives or
mixtures thereof.
[0081] Alternatively, the anti-wear agent is selected from
saturated organic monosulphides, organic polysulphides,
dithiocarbamates, such as zinc dithiocarbamates, zinc
dialkyldithiophosphates (ZDTP), or mixtures thereof.
[0082] By an antioxidant and an anti-wear agent, the invention
relates not only to the case where the composition contains an
additive having an antioxidant function and another additive having
an anti-wear function, but also to the case where the composition
contains an additive having both an antioxidant function and an
anti-wear function. In particular, the composition can comprise one
or more antioxidant(s) and/or one or more anti-wear agent(s).
[0083] Advantageously, the composition contains at least one
antioxidant and at least one anti-wear agent (i.e. two different
additives).
[0084] The composition can also contain at least one other
additive, which can be selected from: [0085] viscosity index
improvers, such as polymers of the olefin copolymer type (OCP),
polyisobutenes, polymethacrylates, diene polymers,
polyalkylstyrenes and/or molybdenum derivatives; [0086] friction
modifiers, such as glycerol monooleate (GMO); [0087]
extreme-pressure additives, such as organometallic molybdenum
derivatives, fatty-acid derived compounds, phosphorus and
sulphur-containing molecules and/or borates; [0088] pour point
depressants, such as metallic soaps, carboxylic acids,
polymethacrylates, alkylphenols, dialkyl aryl phthalic acid esters,
maleate-styrene copolymers, naphthalene paraffins and/or polyesters
of the fumarate-vinyl acetate type; [0089] anti-foaming agents,
such as silicone oils, silicone polymers and/or alkyl acrylates;
[0090] de-emulsifiers, such as propylene oxide copolymers; [0091]
anti-corrosion (or anti-rust) agents such as alkali and/or
alkaline-earth metal sulphonates (Na, Mg, Ca salts), fatty acids,
fatty amines, alkenylsuccinic acids and/or derivatives thereof,
benzotriazole, and/or tolyltriazole; [0092] thickening agents, such
as fatty esters; [0093] detergents, such as calcium and/or
magnesium salts of alkylaryl sulphonates, alkylphenates,
alkylsalicylates and/or derivatives thereof; [0094] dispersants,
such as alkenylsuccinimides, succinic esters and/or derivatives
thereof, and/or Mannich bases; [0095] metal deactivators, such as
heterocyclic compounds containing nitrogen and/or sulphur, for
example triazole, tolutriazole, and benzotriazole;
[0096] or mixtures thereof.
[0097] It should be noted that an additive can have several
properties, for example antioxidant and anti-wear, like zinc
dialkyl dithiophosphate which is an antioxidant additive, anti-wear
agent, anti-corrosion agent and slightly dispersant.
[0098] Moreover, the composition can also comprise at least one oil
which is selected from the aforementioned mineral, natural and/or
synthetic oils, preferentially from the mineral oils and/or the
synthetic oils, more preferentially from the synthetic oils and/or
the hydrorefined oils (oils from Group II according to the
classification of oils established by the American Petroleum
Institute (API) and followed by the Association Technique de
I'Industrie Europeenne des Lubricants (ATIEL)) and/or hydrocracked
oils (oils from Group III according to the API classification).
[0099] The process for the preparation of a composition according
to the first aspect of the invention comprises a step of mixing
di-(2-hexyldecyl) succinate with the antioxidant and/or the
anti-wear agent. During this mixing step, the different
constituents, namely the DHDS, the antioxidant and/or the anti-wear
agent, can be introduced individually. Alternatively, prior to the
mixing step, one or more of the different constituents of the
mixture may have undergone pre-mixing with one or more other
products selected from the aforementioned additives and/or
oils.
[0100] According to a first particular embodiment of a composition
according to the first aspect of the invention, the composition
contains a quantity of DHDS comprised between 50 and 99% by weight,
the percentage by weight being based on the total weight of the
composition. Preferentially, the quantity of DHDS is comprised
between 60 and 98%, more preferentially between 80 and 98% by
weight. These quantities of DHDS are more particularly utilized
when the DHDS is used as base oil in a lubricant composition. In
fact, as DHDS is a synthetic diester, it belongs to the group of
synthetic oils and can therefore constitute a base oil of a
lubricant composition or form part of the composition of a base
oil. However, in the present application, when the term "synthetic
oil" is used, this means any synthetic oil with the exclusion of
DHDS.
[0101] According to a second particular embodiment of a composition
according to the first aspect of the invention, the composition
contains a quantity of DHDS comprised between 2 and 95%,
preferentially, between 5 and 30%, more preferentially, between 7
and 25%, even more preferentially between 10 and 20% by weight, for
example 15% by weight, the percentages by weight being based on the
total weight of the composition.
[0102] These quantities of DHDS are more particularly utilized when
DHDS is used in association with other oils for the base oil in a
lubricant composition.
[0103] In this composition, the quantity of the base oil,
constituted by the DHDS and one or more other oils for the base
oil, is then comprised between 60 and 99.9%, preferentially between
70 and 99.5%, even more preferentially between 75 and 99% by
weight, the percentage by weight being based on the total weight of
the composition.
[0104] Advantageously, the composition according to the first
aspect of the invention can be used as a lubricant composition.
[0105] According to a second aspect of the invention, the present
invention discloses a composition consisting of di-(2-hexyldecyl)
succinate and a base oil. In particular, in this composition, the
base oil is not constituted by di-(2-hexyldecyl) succinate.
[0106] The base oil can be selected from the group constituted by
one or more oils selected from the aforementioned mineral, natural
and/or synthetic oils, preferentially from the mineral oils and/or
the synthetic oils, even more preferentially from the hydrorefined
oils (oils of Group II according to the API classification) and/or
the hydrocracked oils (oils of Group III according to the API
classification).
[0107] The process for the preparation of a composition according
to the second aspect of the invention comprises a step of mixing
di-(2-hexyldecyl) succinate with the base oil.
[0108] According to a particular embodiment of a composition
according to the second aspect of the invention, the quantity of
DHDS in the composition is comprised between 3 and 49.9% by weight,
preferentially between 5 and 35% by weight, more preferentially
between 10 and 30% by weight, even more preferentially between 15
and 25% by weight, the percentages by weight being based on the
total weight of the composition.
[0109] The composition according to the second aspect of the
invention can itself be used as base oil.
[0110] In certain cases in which DHDS is used in small quantities,
the DHDS could be considered as an additive, such as a dispersant.
However, in the present application, when the term "additive" is
used, any additive is meant, with the exclusion of DHDS.
[0111] Advantageously, the compositions according to the first and
the second aspect of the invention (hereinafter denoted "the
compositions according to the invention"), can be used for the
preparation of a lubricant composition, in particular for the
automotive sector, the industrial sector and the metalworking
sector.
[0112] In fact, the composition according to the first aspect of
the invention can be used directly as a lubricant composition or as
a pre-mix for a lubricant composition, pre-mix to which may be
added one or more additive(s) and/or one or more oil(s) for the
base oil.
[0113] Examples of lubricant compositions for the automotive sector
are hydraulic oils (or fluids), transmission fluids, cooling
fluids, engine oils, oils for axles, gearbox fluids, brake fluids,
shock-absorber oils and damper oils. In the present application,
the terms "oil" and "fluid" are used interchangeably in the
designation of the applications/utilizations of the compositions
according to the invention.
[0114] By industrial sector lubricant compositions is meant more
particularly industrial transmission oils, compressor oils, turbine
oils, gear oils and/or hydraulic oils. These oils all have a water
content less than 5000 ppm, preferentially less than or equal to
1000 ppm.
[0115] Examples of lubricant compositions of the metalworking
sector are rolling oils, cutting oils, grinding oils, quenching
oils, drawing and stamping oils and casting oils.
[0116] Preferentially, the lubricant compositions are used as
engine oil and/or hydraulic oil and/or gear oil and/or metalworking
oil, more preferentially for engine oil and/or hydraulic oil.
[0117] Thus the compositions according to the invention can be used
for the preparation of an engine oil, a hydraulic oil, a gear oil,
and/or a metalworking oil.
[0118] In fact, DITA is frequently used in this type of lubricant
composition. In view of the properties of DHDS, it can be used as a
substitute product for DITA and advantageously replace the latter
in such lubricant compositions.
[0119] In addition, the lubricant compositions are utilized under
demanding conditions of use, in particular in terms of operating
temperatures.
[0120] Now, DHDS has a low pour point (-64.degree. C.) and a high
flash point (264.degree. C.), which makes it usable over a wide
range of temperatures, in particular at extreme winter or summer
temperatures, which are the temperatures to which an engine oil, a
hydraulic oil, a gear oil and a metalworking oil may be
exposed.
[0121] DHDS also has very good compatibility with the elastomers
which constitute, for example, the seals present in engines.
[0122] All these properties make DHDS a product of choice for use
in the automotive sector, the industrial sector and/or the
metalworking sector.
[0123] According to a third, fourth, fifth and sixth aspect of the
invention, the latter also relates to: [0124] an engine oil
containing di-(2-hexyldecyl) succinate, [0125] a hydraulic oil
containing di-(2-hexyldecyl) succinate, [0126] a gear oil
containing di-(2-hexyldecyl) succinate, or [0127] a metalworking
oil containing di-(2-hexyldecyl) succinate.
[0128] The third aspect of the invention relates to an engine oil
containing DHDS. An engine oil makes it possible in particular to
lubricate the engine of a vehicle. Such an oil contains at least
one base oil and at least one additive.
[0129] Preferentially, the quantity of base oil is comprised
between 55 and 90% by weight, more preferentially between 80 and
85% by weight, the percentages by weight being based on the total
weight of engine oil.
[0130] The base oil can be constituted by DHDS.
[0131] Alternatively, the base oil can be constituted by DHDS and
one or more oil(s) for the base oil. The quantity of DHDS present
in the base oil is then comprised between 1 and 30% by weight,
preferentially between 5 and 25% by weight, more preferentially
between 10 and 20% by weight, the percentages by weight being based
on the total weight of engine oil.
[0132] Preferably, the base oil is constituted by DHDS and one or
more oils selected from the aforementioned mineral, natural and/or
synthetic oils, preferentially from mineral oils and/or synthetic
oils, even more preferentially from synthetic oils, hydrorefined
oils (oils from Group II according to the API classification)
and/or hydrocracked oils (oils from Group III according to the API
classification).
[0133] Advantageously, the additive(s) is/are chosen from
antioxidants, anti-wear agents, dispersants, viscosity index
improvers and/or friction modifiers. Preferably, the engine oil
contains at least one antioxidant and one dispersant, more
preferentially an antioxidant and a dispersant, an anti-wear agent
and/or a viscosity index improver. Optionally, a detergent and/or
an anti-foaming agent can be present in the engine oil.
[0134] According to a particular embodiment of an engine oil
according to the third aspect of the invention, the engine oil
comprises one of the compositions according to the invention.
[0135] Preferably, an engine oil, regardless of the embodiment,
comprises an antioxidant selected from the group constituted by
zinc dialkyldithiophosphates (ZDTP), sulphurized olefins,
sulphurized phenols, aromatic amines, or mixtures thereof.
[0136] By way of example, a 4-stroke engine oil for a car
"Passenger Car Motor Oil" (PCMO) can contain: [0137] 55 to 90% by
weight of a base oil (containing for example one or more
polyalphaolefins (PAO), one or more hydrocracked oils, one or more
hydrorefined oils, one or more esters and/or one or more other base
oils) including 1 to 20% by weight of DHDS, [0138] 2 to 18% by
weight of viscosity index improvers, [0139] 5 to 23% by weight of
at least one additive (at least an anti-wear agent, an antioxidant
and a dispersant; a single additive, such as zinc
dialkyldithiophosphate, being able to carry out these 3 functions,
and optionally a detergent, an anti-foaming agent and/or one or
more other additives), [0140] 0 to 4% by weight of a friction
modifier, the percentages by weight being based on the total weight
of motor oil.
[0141] Preferably, the antioxidant and/or the anti-wear agent of
this 4-stroke engine oil is/are selected from the antioxidants used
in the field of lubricants and/or the anti-wear agents used in the
field of lubricants such as those described in the first aspect of
the invention and more particularly, the antioxidants may be
selected from those preferred for this third aspect of the
invention.
[0142] A fourth aspect of the invention relates to a hydraulic oil
containing DHDS. A hydraulic oil makes it possible in particular to
lubricate a cylinder. Such an oil contains at least one base oil.
Preferentially, the quantity of base oil is comprised between 90
and 99.5% by weight, more preferentially between 95 and 99% by
weight, the percentages by weight being based on the total weight
of hydraulic oil. Advantageously, the quantity of DHDS present in
the base oil is comprised between 5 and 99.5% by weight,
preferentially between 10 and 99% by weight, more preferentially
between 15 and 98% by weight, the percentages by weight being based
on the total weight of hydraulic oil.
[0143] The base oil can be constituted by DHDS. Alternatively, the
base oil is constituted by DHDS and one or more oil(s) selected
from the aforementioned mineral, natural and/or synthetic oils,
preferentially from the mineral oils and/or the synthetic oils,
even more preferentially from the esters and/or the
polyalphaolefins.
[0144] Advantageously, the additives are selected from
antioxidants, anti-wear agents and/or anti-foaming agents.
Preferably, the hydraulic oil contains at least an antioxidant.
[0145] According to a particular embodiment of a hydraulic oil
according to the fourth aspect of the invention, the hydraulic oil
contains one of the compositions according to the invention.
[0146] Preferably, a hydraulic oil, regardless of the embodiment,
contains an antioxidant selected from the group constituted by
hindered substituted phenols, aromatic amines, saturated organic
monosulphides, organic polysulphides, sulphurized olefins,
sulphurized phenols, phosphites, dithiophosphates, or mixtures
thereof.
[0147] Preferably, the anti-wear agent used in a hydraulic oil,
regardless of the embodiment, is selected from the group
constituted by saturated organic monosulphides, organic
polysulphides, such as dialkyl disulphides and dialkyltrisulphide,
sulphurized olefins, dithiocarbamates such as zinc
dithiocarbamates, zinc dialkyldithiophosphates (ZDTP),
tricresylphosphates (TCP), phosphate amines, chlorinated compounds,
compounds comprising molybdenum, or mixtures thereof.
[0148] By way of example, a hydraulic oil can contain: [0149] 95 to
99.5% by weight of a base oil constituted by DHDS or containing
DHDS and one or more polyalphaolefin(s) and/or one or more ester(s)
such as diesters and/or polyol esters such as trimethylolpropane
oleate, [0150] 0.5 to 3% by weight of antioxidant(s), [0151] 0 to
1% by weight of anti-wear agent(s), [0152] 0 to 0.1% by weight of
anti-foaming agent(s), [0153] 0 to 0.5% by weight of yellow metal
deactivator, [0154] 0 to 1.5% by weight of other additives, the
percentages by weight being based on the total weight of hydraulic
oil.
[0155] Preferably, the antioxidant and/or the anti-wear agent of
this hydraulic oil is/are selected from the antioxidants used in
the field of lubricants and/or the anti-wear agents used in the
field of lubricants such as those described in the first aspect of
the invention and more particularly, the antioxidants and/or the
anti-wear agents may be selected from those preferred for this
fourth aspect of the invention.
[0156] A fifth aspect of the invention relates to a gear oil
containing DHDS. The gear oil according to the fifth aspect of the
invention contains at least one base oil and at least one
additive.
[0157] Preferentially, the quantity of base oil is comprised
between 70 and 98% by weight, more preferentially between 70 and
95% by weight, the percentages by weight being based on the total
weight of gear oil.
[0158] The base oil can be constituted by DHDS.
[0159] Alternatively, the base oil can be constituted by DHDS and
one or more oil(s) for the base oil. The quantity of DHDS present
in the base oil is then comprised between 5 and 60% by weight,
preferentially between 5 and 30% by weight, more preferentially
between 10 and 25% by weight, the percentages by weight being based
on the total weight of gear oil.
[0160] Preferably, the base oil is constituted by DHDS and one or
more oils selected from the aforementioned mineral, natural and/or
synthetic oils, preferentially from mineral oils and/or synthetic
oils, even more preferentially from synthetic oils, hydrorefined
oils (oils from Group II according to the API classification)
and/or hydrocracked oils (oils from Group III according to the API
classification).
[0161] Advantageously, the additives are selected from
antioxidants, viscosity improvers, anti-corrosion agents,
dispersants, pour point depressants and/or anti-wear agents.
Preferably, the gear oil comprises at least one antioxidant and/or
one viscosity improver.
[0162] According to a particular embodiment of a gear oil according
to the fifth aspect of the invention, the gear oil comprises one of
the compositions according to the invention.
[0163] Preferably, a gear oil, regardless of the embodiment,
comprises an antioxidant selected from the group constituted by
hindered substituted phenols, sulphurized phenols, sulphurized
hindered substituted phenols, aromatic amines, saturated organic
monosulphides, organic polysulphides such as dialkyl disulphides
and dialkyl trisulphides, zinc dialkyldithiophosphates (ZDTP),
aromatic amines, or mixtures thereof. More preferentially, the
antioxidant is selected from the group constituted by
2,6-di-t-butyl-4-methylphenol (BHT),
4,4'-methylenebis(2,6-di-tert-butylphenol) (MBDTBP),
3,5-di-tert-butyl-4-hydroxyhydrocinnamate (ABHHC),
2,6-di-tert-butylphenol (DTBP), sulphurized alkylphenols, aromatic
amines, dialkyl disulphides, dialkyl trisulphides, zinc
dialkyldithiophosphates (ZDTP), or mixtures thereof.
[0164] Preferably, the anti-wear agent used in a gear oil,
regardless of the embodiment, is selected from the group
constituted by saturated organic monosulphides, organic
polysulphides such as dialkyl disulphides and dialkyltrisulphides,
sulphurized olefins, dithiocarbamates, such as zinc
dithiocarbamates, phosphites, zinc dialkyldithiophosphates (ZDTP),
chlorowaxes, potassium triborate, or mixtures thereof.
[0165] By way of example, a gear oil can contain: [0166] 70 to 95%
by weight of a base oil comprising 10 to 25% of DHDS and one or
more mineral oil(s) and/or one or more synthetic oil(s), [0167] 5
to 30% by weight of additives, including at least one antioxidant,
a viscosity improver, a dispersant, a pour point depressant, an
anti-corrosion agent, a friction modifier, and/or an anti-foaming
agent,
[0168] the percentages by weight being based on the total weight of
the gear oil.
[0169] Preferably, the antioxidant and/or the anti-wear agent of
this gear oil is/are selected from the antioxidants used in the
field of lubricants and/or the anti-wear agents used in the field
of lubricants such as those described in the first aspect of the
invention and more particularly, the antioxidants and/or the
anti-wear agents may be selected from those preferred for this
fifth aspect of the invention.
[0170] A sixth aspect of the invention relates to an oil for metal
working containing DHDS. The metalworking oil according to the
sixth aspect of the invention contains at least one base oil and at
least one additive.
[0171] Preferably, the metalworking oil is used as a rolling oil, a
cutting oil, a grinding oil, a quenching oil, a drawing and
stamping oil, or a casting oil.
[0172] Preferentially, the quantity of base oil is comprised
between 60 and 98% by weight, more preferentially between 70 and
95% by weight, the percentages by weight being based on the total
weight of metalworking oil.
[0173] The base oil can be constituted by DHDS.
[0174] Alternatively, the base oil can be constituted by DHDS and
one or more oil(s) for the base oil. The quantity of DHDS present
in the base oil, is then comprised between 2 and 60% by weight,
preferentially between 5 and 30% by weight, more preferentially
between 10 and 20% by weight, the percentages by weight being based
on the total weight of metalworking oil.
[0175] Preferably, the base oil is constituted by DHDS and one or
more oils selected from the aforementioned mineral, natural and/or
synthetic oils, preferentially from mineral oils and/or synthetic
oils, even more preferentially from synthetic oils, hydrorefined
oils (oils from Group II according to the API classification)
and/or hydrocracked oils (oils from Group III according to the API
classification).
[0176] Advantageously, the additives are selected from antioxidants
and/or anti-wear agents. Preferably, the metalworking oil comprises
at least an antioxidant and/or a anti-wear agent.
[0177] According to a particular embodiment of a metalworking oil
according to the sixth aspect of the invention, the metalworking
oil comprises one of the compositions according to the
invention.
[0178] By way of example, a metalworking oil can comprise: [0179]
70 to 95% by weight of a base oil comprising 3 to 18% of DHDS and
one or more mineral oil(s) and/or one or more synthetic oil(s),
[0180] 5 to 30% by weight of additives, including at least an
antioxidant and/or an anti-wear agent,
[0181] the percentages by weight being based on the total weight of
the metalworking oil.
[0182] Preferably, the antioxidant and/or the anti-wear agent of
this metalworking oil is/are selected from antioxidants used in the
field of lubricants and/or anti-wear agents used in the field of
lubricants such as those described in the first aspect of the
invention.
[0183] Preferably, the compositions according to the invention, the
engine oil, the hydraulic oil, the gear oil and the metalworking
oil are oily compositions, each having a water content less than
5000 ppm, preferentially less than or equal to 1000 ppm.
[0184] The present invention also discloses a process for improving
the lubricating power and/or the hydrolytic stability and/or the
oxidation stability and/or the compatibility with elastomers and/or
the solvent power of a composition, comprising the introduction of
di-(2-hexyldecyl) succinate into the composition.
[0185] The improvement provided by the introduction of DHDS depends
on the compounds of the composition. In particular, the greater the
quantity of DHDS introduced into the composition, the greater will
be the improvement in one or more of the aforementioned
properties.
[0186] The introduction of DHDS can be carried out either by the
addition of DHDS to a pre-existing composition, or by the partial
or total substitution of one or more compound(s) of the
pre-existing composition by DHDS.
[0187] The improved composition according to the aforementioned
process is advantageously a lubricant composition, such as an
engine oil, a hydraulic oil, a gear oil and/or a metalworking oil.
In this case, the improvement(s) depend(s) on the base oil present
in the lubricant composition. In fact, the properties of the base
oil can in particular vary according to whether it is constituted
by mineral, natural and/or synthetic oil(s). Among the synthetic
oils, the properties also differ between the polyalphaolefins
(moderate lubricating power), the saturated esters (pour point
temperature a little high) and the unsaturated esters (low
oxidation stability).
[0188] In particular, if the composition comprises a compound that
has a low lubricating power such as one or more mineral oil(s), one
or more polyalphaolefin(s) (PAO), or mixtures thereof, or any
compound that has a lubricating power less than that of DHDS, the
introduction of DHDS into this composition will improve the
lubricating power of the composition.
[0189] Similarly, if the composition comprises a compound that has
a low hydrolytic stability such as one or more mineral oil(s), the
introduction of DHDS into this composition will improve the
hydrolytic stability of the composition.
[0190] For example, a low hydrolytic stability corresponds to a
measurement of the difference in acid value greater than 0.2 mg
KOH/g, a measurement of the kinematic viscosity variation at
40.degree. C. greater than 2%, and/or a measurement of the
variation in the weight of the copper plate greater than 0.15
mg/cm.sup.2; the measurements being carried out according to the
standard ASTM D 2619.
[0191] Furthermore, if the composition comprises a compound that
has a low oxidation stability, such as trimethylolpropane trioleate
(TMPTO), the introduction of DHDS into this composition will
improve the oxidation stability of the composition.
[0192] For example, a low oxidation stability corresponds to a
measurement of less than 300 minutes, according to the standard
ASTM D 2272 in the presence of Additin RC 9321.
[0193] Similarly, if the composition comprises a compound that has
a compatibility with elastomers less than that of DHDS, such as
DITA, the introduction of DHDS into this composition will improve
the compatibility with elastomers of the composition.
[0194] Finally, if the composition comprises a compound having a
low solvent power, such as one or more mineral oil(s), the
introduction of DHDS into this composition will improve the solvent
power of the composition.
[0195] Preferably, the introduction of DHDS will make it possible
to improve the lubricating power and/or the hydrolytic stability
and/or the compatibility with elastomers of a composition.
[0196] Preferentially, the DHDS is introduced into the composition
in order to improve the lubricating power and/or the hydrolytic
stability, even more preferentially, in order to improve the
hydrolytic stability of a composition.
[0197] In fact, the hydrolytic stability of DHDS is particularly
good (see Example 2 Table 1). As a result, di-(2-hexyldecyl)
succinate can advantageously be used in order to improve the
hydrolytic stability of a composition, in particular of a lubricant
composition.
[0198] Moreover, DHDS has a biodegradability greater than 60%
(measured according to OECD test 301 B) and an aquatic toxicity
greater than 100 mg/L (measured according to OECD tests 201, 202
and 203), making it possible to obtain the European EcoLabel
according to Decision No. 2005/360/EC of 26 Apr. 2005 establishing
the ecological criteria and the associated requirements in respect
of evaluation and verification pour attribution of the Community
ecological label to lubricants.
[0199] Apart from the specific advantageous properties of
di-(2-hexyldecyl) succinate, the latter has a further advantage,
which is that of the ability to be prepared from renewable
resources.
[0200] By renewable resources is meant the products originating
from plants, animals or algae.
[0201] One means of obtaining di-(2-hexyldecyl) succinate is the
esterification of succinic acid with 2-hexyldecanol.
[0202] Succinic acid can be produced by fermentation, using glucose
originating from wheat, for example according to the process
developed by BioAmber.RTM.. Apart from the fact of using a raw
material of renewable origin, this process has the advantage of
requiring the consumption of CO.sub.2 and therefore in addition
participates in the reduction of greenhouse gases. After extraction
and crystallization, succinic acid is obtained in the form of a
white powder. Analysis of the carbon 14 level thereof revealed the
presence of 97% carbon of renewable origin according to the
standard ASTM D 6866.
[0203] Determination of the percentage of carbon of renewable
origin or renewability content can be carried out preferably
according to the standard ASTM D 6866, by measuring the content of
carbon 14 present in the product. A molecule of renewable origin
(originating from a plant, animal or alga) in fact contains a
characteristic quantity of carbon 14, which distinguishes it from
products of fossil origin, which do not contain carbon 14.
[0204] 2-hexyldecanol can be obtained from octanol via the Guerbet
reaction, the octanol being able to be prepared from vegetable
oils.
[0205] For example, starting from coco oil, it is possible to
prepare a caprylic acid methyl ester, by transesterification of
this oil with methanol, followed by purification by distillation.
This caprylic acid ester is then reduced in order to obtain
octanol. During this last step, methanol is eliminated from the
chemical structure of the octanol. Then only the carbons of plant
origin remain in the octanol.
[0206] As indicated above, 2-hexyldecanol can be synthesized from
octanol following the Guerbet reaction. Such a reaction is
described in U.S. Pat. No. 4,518,810. For example, octanol, in the
presence of water and a catalyst, is heated at 180.degree. C.,
preferentially at 200.degree. C., even more preferentially at
220.degree. C.
[0207] The inventors carried out the esterification reaction
between succinic acid and 2-hexyldecanol of renewable origin.
Analysis of the renewability content according to standard ASTM D
6866 of the di-(2-hexyldecyl) succinate thus obtained revealed that
the DHDS contained 96% carbon of renewable origin.
[0208] The invention also relates to di-(2-hexyldecyl) succinate
containing at least 80% carbon of renewable origin, preferentially
at least 90%, even more preferentially at least 95%, in particular
96%, the determination of the percentage of carbon of renewable
origin being carried out according to the standard ASTM D 6866.
[0209] Such a di-(2-hexyldecyl) succinate is advantageously
obtained by esterification of succinic acid with 2-hexyldecanol,
the succinic acid being obtained by fermentation using wheat
glucose and the 2-hexyldecanol being obtained from octanol via the
Guerbet reaction, the octanol being prepared from vegetable oils.
Consequently, DHDS represents an effective alternative to DITA, and
due to its renewable origin, one that is more environmentally
friendly.
[0210] Advantageously, the compositions according to the invention,
the engine oil, the hydraulic oil, the gear oil and the
metalworking oil according to the invention, comprise
di-(2-hexyldecyl) succinate that contains at least 90% carbon of
renewable origin.
[0211] The di-(2-hexyldecyl) succinate that contains at least 90%
carbon of renewable origin is advantageously used in a lubricant
composition.
[0212] In particular, the di-(2-hexyldecyl) succinate containing at
least 90% carbon of renewable origin is used in a base oil.
[0213] In particular, the di-(2-hexyldecyl) succinate containing at
least 90% carbon of renewable origin is used in order to increase
the percentage of carbon of renewable origin of a composition, in
particular of a lubricant composition.
[0214] In particular, the compositions according to the invention
in which the di-(2-hexyldecyl) succinate contains at least 90%
carbon of renewable origin can be used in order to increase the
percentage of carbon of renewable origin of a composition, in
particular of a lubricant composition.
[0215] Preferentially, the di-(2-hexyldecyl) succinate contains at
least 95%, even more preferentially 96% carbon of renewable
origin.
[0216] Other characteristics and advantages of the invention will
become apparent from the following examples, given by way of
illustration only, and with reference to FIG. 1 which is a
graphical representation of the chemical structure of DHDS.
EXAMPLE 1
Preparation of di-(2-hexyldecyl) Succinate
[0217] The di-(2-hexyldecyl) succinate shown in FIG. 1 can be
prepared via a conventional esterification process by heating
succinic acid with at least a stoichiometric quantity of
2-hexyldecanol.
[0218] Preparation of 2-hexyldecanol
[0219] 30 g of an aqueous solution of KOH and 0.2 g of a Cu/Ni
catalyst (in a proportion 80/20) were added to 1020 g of octanol
prepared from renewable resources. While bubbling nitrogen through
the medium at a flow rate of 30 L/hour, the reaction medium was
heated until reaching 220.degree. C. after 2 h30. After 1 hour at
this temperature, the medium was cooled down and filtered. The
filtrate was distilled under reduced pressure in order to give
2-hexyldecanol.
[0220] Esterification of Succinic Acid
[0221] 2.05 mol of 2-hexyldecanol as prepared above, 1 mol of
succinic acid (BioAmber.RTM.) and 0.05% of a metallic catalyst were
introduced into a reactor equipped with a mechanical stirrer, under
a nitrogen atmosphere. The temperature of the reaction medium was
taken rapidly to 150.degree. C., then gradually increased
(10.degree. C./hour) until reaching 220.degree. C.
[0222] When the acid value had stabilized at a value less than 0.5
mg KOH/g, the reaction medium was neutralized by the addition of a
stoichiometric quantity of a 50% soda solution.
[0223] The residue was filtered through a Gauthier filter in the
presence of 1% of a silicate type filtration adjuvant.
[0224] In this way, DHDS is obtained, prepared from resources of
renewable origin.
EXAMPLE 2
Determination of the Properties of di-(2-hexyldecyl) Succinate and
Comparison with di-isotridecyl Adipate
[0225] 1. Materials
[0226] The following three esters were tested: [0227] DHDS was
prepared according to the process described in Example 1. [0228]
DITA was prepared according to a process similar to that of Example
1, from adipic acid and isotridecanol. [0229] Di-isostearyl
succinate (DISu) was prepared according to a process similar to
that of Example 1, from succinic acid and isostearyl alcohol.
[0230] 2. Methods
[0231] 2.1 Acid Value
[0232] The acid value was measured according to the standard ASTM D
664.
[0233] 2.2 Hydroxyl Value
[0234] The hydroxyl value was measured according to the standard
AOCS Cd 13-60.
[0235] 2.3 Saponification Number
[0236] The saponification number was measured according to the
standard AOCS Cd 3-25.
[0237] 2.4 Kinematic Viscosity
[0238] The kinematic viscosities at 40.degree. C. and at
100.degree. C. were measured according to the standard ASTM D
445.
[0239] 2.5 Viscosity Index
[0240] The viscosity index was calculated according to the standard
ASTM D 2270.
[0241] 2.6 Flash Point
[0242] The flash point was measured according to the standard ASTM
D 92.
[0243] 2.7 Pour Point
[0244] The pour point was measured according to the standard ASTM D
97.
[0245] 2.8 Fire Point
[0246] The fire point was measured according to the standard ASTM D
92.
[0247] 2.9 Hydrolytic Stability
[0248] The hydrolytic stability was measured according to the
standard ASTM D 2619 (Beverage bottle method).
[0249] A mixture of 75 g of one of the esters tested and 25
cm.sup.3 of water as well as a copper plate were enclosed in a
capped Coca Cola bottle. The whole was placed under slow rotation
for 48 h in an oven at 93.degree. C. At the end of the test, the
acid value and the kinematic viscosity at 40.degree. C. of the
ester, the weight of the copper plate, as well as the acidity of
the aqueous phase were measured.
[0250] 2.10 Oxidation Stability
[0251] The oxidation stability was measured according to the
standard ASTM D 2272 method A (Rotating Pressure Vessel Oxidation
Test (RPVOT)) with 1.5% of Additin RC9321).
[0252] The RPVOT method measures the resistance to oxidation by the
air of an oil under specific conditions. It makes it possible to
evaluate the service life of an oil by determining the break point
or the induction period of a sample of oil in the presence of
oxygen, water and a copper-based catalyst. In the present
application, DHDS and DITA formulated respectively with 1.5% of
Additin RC 9321.RTM. (mixture of antioxidant and anti-corrosion
agent well known to a person skilled in the art, used as reference,
marketed by RheinChemie-Lanxess.RTM.) were tested. Each sample was
placed in a container under pressure and rotated at an angle of
30.degree. at a speed of 100 rpm in an oil bath heated to a high
temperature (150.degree. C.). The number of minutes necessary in
order to reach a specific pressure drop represents the oxidation
stability of the sample.
[0253] 2.11 Compatibility with Elastomers
[0254] The compatibility with elastomers was measured according to
the standard ISO 1817 by heating at 80.degree. C. for 168
hours.
[0255] 2.12 Renewability
[0256] The renewability was measured according to the standard ASTM
D 6866.
[0257] 3. Results
[0258] The results are presented in Table 1 below:
TABLE-US-00001 TABLE 1 DITA DHDS DISu Acid value (mg KOH/g) 0.1
0.02 0.09 Hydroxyl value (mg KOH/g) <4 0 13.5 Saponification
number (mg KOH/g) 215-225 206 176 Kinematic viscosity at 40.degree.
C. 27.3 26.8 44.2 (mm.sup.2/s) Kinematic viscosity at 100.degree.
C. 5.37 5.30 8.50 (mm.sup.2/s) Viscosity index 135 142 Flash point
(.degree. C.) 236 264 234 Pour point (.degree. C.) -57 -64 -7 Fire
point (.degree. C.) 266 286 262 Hydrolytic stability Acid value
before test (mg KOH/g) 0.03 0.02 0.09 Acid value after test (mg
KOH/g) 0.11 0.08 0.27 Difference in acid value (mg KOH/g) 0.08 0.06
0.18 Acidity of the aqueous phase 0.07 0.07 0.01 (mg KOH/g)
Kinematic viscosity at 40.degree. C. 23.7 26.8 44.2 before test
(mm.sup.2/s) Kinematic viscosity at 40.degree. C. 23.9 26.7 40.0
after test (mm.sup.2/s) Kinematic viscosity variation at 0.8 -0.4
-10.5 40.degree. C. (%) Appearance of the copper plate 3a* 2c* 3a*
Weight of the copper plate before 4.9877 5.2623 5.3640 test (g)
Weight of the copper plate after 4.9870 5.2613 5.3637 test (g)
Variation in the weight of the 0.05 0.05 0.02 copper plate
(mg/cm.sup.2) Oxidation stability (min) 1120 835 Compatibility with
elastomers Volume difference of the NBR 1 15 6.8 (%) Volume
difference of the HNBR 1 11.2 4.4 (%) Volume difference of the FKM
2 0.5 0 (%) Renewability (% carbon 14) 0 96 *The appearance of the
copper was determined according to the colour scale, varying from
light orange (1a) to glassy black (4c), given in the standard ASTM
D 130.
[0259] It is noted that the DHDS has: [0260] good viscosity and in
particular a kinematic viscosity at 40.degree. C. of 27.3
mm.sup.2/s, a kinematic viscosity at 100.degree. C. of 5.37
mm.sup.2/s, measured according to the standard ASTM D 445, [0261]
good hydrolytic stability, measured according to the standard ASTM
D 2619, by a small difference in acid value (0.06 mg KOH/g), a low
kinematic viscosity variation at 40.degree. C. (-0.4%) and a low
variation in the weight of the copper plate (0.05 mg/cm.sup.2),
[0262] good oxidation stability, [0263] good low-temperature
stability, in particular with a pour point equal to -64.degree. C.,
measured according to the standard ASTM D 97, and [0264] good
compatibility with elastomers selected from acrylonitrile butadiene
rubber, such as NBR 1, hydrogenated acrylonitrile-butadiene rubber,
such as HNBR 1, fluorinated rubber, such as FKM 2.
[0265] The improved hydrolytic stability of the DHDS compared to
the DITA can be observed by the difference in acid value and the
viscosity variation that are lower for the DHDS than for the
DITA.
[0266] The pour point of the DHDS (-64.degree. C.) is lower than
that of the DITA (-57.degree. C.), which demonstrates a better
low-temperature stability.
[0267] As regards the compatibility with elastomers, the volume
difference (or swelling) observed for the DHDS is 6.8% with the NBR
1, whereas it is 15% with the DITA under the same conditions. The
volume difference observed for the DHDS is 4.4% with the HNBR 1,
whereas it is 11.2% with the DITA under the same conditions. No
volume variation was observed for the DHDS with the fluorinated
rubber (FKM 2), whereas a volume variation of 0.5% was observed
with the DITA under the same conditions. The DHDS thus has a better
compatibility with elastomers than the DITA.
[0268] The viscosity index of DHDS (142) is also better than that
of DITA (135). DHDS therefore has a viscosity that is more stable
under temperature variations than DITA, which makes it possible to
reduce the impact of temperature on the performance of the
composition constituted by DHDS, in particular a lubricant
composition (as the performance of a lubricant composition is very
closely linked to the viscosity).
[0269] The flash point of DHDS (264.degree. C.) is higher than that
of DITA (236.degree. C.), which makes DHDS usable over a wide range
of temperatures, in particular at higher temperatures than
DITA.
[0270] DISu does not have good hydrolytic stability. Its kinematic
viscosity at 40.degree. C. is higher (44 mm.sup.2/s) than that of
DITA and its pour point is too high (-7.degree. C.) with respect to
the desired properties. Therefore this diester does not have the
necessary properties to be able to substitute for DITA.
EXAMPLE 3
Composition of an Engine Oil Comprising Only Synthetic Oils
[0271] An engine oil based on synthetic oils is prepared by mixing
the following compounds (in % by weight of the total weight of the
composition): [0272] PAO 40 (polyalphaolefin having a kinematic
viscosity at 100.degree. C. comprised between 38 and 42 cSt): 52%,
[0273] PAO 6 (polyalphaolefin having a kinematic viscosity at
100.degree. C. comprised between 5.8 and 6.2 cSt): 22%, [0274]
DHDS: 15%, [0275] HiTEC.RTM. 1255 (additive package comprising
dispersants and inhibitors): 10%, [0276] HiTEC.RTM. 4702
(antioxidant): 0.5%, [0277] Irganox.RTM. L-57 (antioxidant):
0.5%.
[0278] This engine oil has a kinematic viscosity at 100.degree. C.
comprised between 16.3 and 21.9 cSt, which makes this an SAE 50
grade oil.
[0279] "cSt" represents centistoke, which is a unit of measurement
that is usual in the field of lubricants (1 cSt=1 mm.sup.2/s).
EXAMPLE 4
Composition of an Engine Oil Comprising a Vegetable Oil
[0280] An engine oil based on vegetable oil is prepared by mixing
the following compounds (in % by weight of the total weight of the
composition): [0281] Vegetable oil esters: 40.4%, [0282]
Hydrorefined oils (Group II): 24%, [0283] DHDS: 20%, [0284]
Viscosity improvers: 2.5%, [0285] Dispersants: 12%, [0286] Pour
point depressant: 0.1%, [0287] Antioxidant: 1%.
EXAMPLE 5
Composition of a Hydraulic Oil
[0288] The hydraulic oil is prepared by mixing the following
compounds (in % by weight of the total weight of the composition):
[0289] DHDS: 97.75%, [0290] Dioctyldiphenylamine (antioxidant): 1%,
[0291] Butylated hydroxytoluene (antioxidant): 1%, [0292] Alkylated
benzotriazole (anti-corrosion agent): 0.1%, [0293] Succinic
anhydride amine (anti-rust agent): 0.1%, [0294] Silicone polymer
(anti-foaming agent): 0.05%.
EXAMPLE 6
Composition of a Gear Oil
[0295] A gear oil was prepared by mixing the following compounds
(in % by weight of the total weight of the composition): [0296] PAO
8 (polyalphaolefin having a kinematic viscosity at 100.degree. C.
comprised between 7.7 and 8.2 cSt): 50.6%, [0297] DHDS: 15%, [0298]
Polyol ester (Radialub.RTM. 7257 marketed by Oleon.RTM.): 25%,
[0299] Viscosity improvers (Viscobase.RTM. 11-574, marketed by
Evonik.RTM.): 6% [0300] Additive package (HiTEC.RTM. 307
(comprising antioxidants and anti-corrosion agents, marketed by
BASF.RTM.): 2.65% [0301] Antioxidant (Irganox.RTM. L135, marketed
by BASF.RTM.): 0.3% [0302] Antioxidant (Irganox.RTM. L06, marketed
by BASF.RTM.): 0.45%.
EXAMPLE 7
Composition of a Metalworking Oil
[0303] A rolling oil was prepared by mixing the following compounds
(in % by weight of the total weight of the composition): [0304]
DHDS: 56%, [0305] Hydrorefined oil: 20%, [0306] Trimethylolpropane
trioleate: 3%, [0307] Additive package comprising an antioxidant, a
dispersant and a detergent: 21%.
* * * * *