U.S. patent application number 13/878825 was filed with the patent office on 2013-08-08 for motor having improved properties.
This patent application is currently assigned to Evonik Oil Additives GmbH. The applicant listed for this patent is Trilby Cressman, Justin August Langston, Peter Moore, Jen-Lung Wang, Michael E. Webb. Invention is credited to Trilby Cressman, Justin August Langston, Peter Moore, Jen-Lung Wang, Michael E. Webb.
Application Number | 20130199482 13/878825 |
Document ID | / |
Family ID | 44510986 |
Filed Date | 2013-08-08 |
United States Patent
Application |
20130199482 |
Kind Code |
A1 |
Langston; Justin August ; et
al. |
August 8, 2013 |
MOTOR HAVING IMPROVED PROPERTIES
Abstract
The present invention describes a motor designed for Fuel
compatibility comprising a lubricant composition comprises at least
one ester group containing polymer having a high polarity.
Inventors: |
Langston; Justin August;
(Kutztown, PA) ; Webb; Michael E.; (Sellersville,
PA) ; Moore; Peter; (Glenside, PA) ; Cressman;
Trilby; (Palmyra, NJ) ; Wang; Jen-Lung;
(Villanova, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Langston; Justin August
Webb; Michael E.
Moore; Peter
Cressman; Trilby
Wang; Jen-Lung |
Kutztown
Sellersville
Glenside
Palmyra
Villanova |
PA
PA
PA
NJ
PA |
US
US
US
US
US |
|
|
Assignee: |
Evonik Oil Additives GmbH
Darmstadt
DE
|
Family ID: |
44510986 |
Appl. No.: |
13/878825 |
Filed: |
August 23, 2011 |
PCT Filed: |
August 23, 2011 |
PCT NO: |
PCT/EP2011/064412 |
371 Date: |
April 11, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61393076 |
Oct 14, 2010 |
|
|
|
Current U.S.
Class: |
123/1A ;
508/459 |
Current CPC
Class: |
C10M 2219/046 20130101;
C10N 2040/255 20200501; C10N 2030/24 20200501; C10M 2201/066
20130101; C10M 149/10 20130101; C10M 2219/022 20130101; C10N
2040/25 20130101; C10M 2209/086 20130101; C10N 2040/251 20200501;
C10M 149/02 20130101; C10M 2201/041 20130101; C10M 2209/084
20130101; C10M 2211/00 20130101; C10M 2219/024 20130101; C10M
145/02 20130101; C10N 2060/09 20200501; C10M 2209/084 20130101;
C10M 2217/028 20130101; C10N 2020/04 20130101; C10M 2209/084
20130101; C10M 2217/028 20130101; C10M 2209/084 20130101; C10M
2217/06 20130101; C10M 2209/084 20130101; C10M 2217/06 20130101;
C10N 2020/04 20130101; C10M 2209/086 20130101; C10M 2217/028
20130101; C10M 2209/084 20130101; C10M 2217/028 20130101; C10N
2020/04 20130101; C10M 2209/084 20130101; C10M 2217/06 20130101;
C10N 2020/04 20130101 |
Class at
Publication: |
123/1.A ;
508/459 |
International
Class: |
C10M 145/02 20060101
C10M145/02 |
Claims
1: A motor, comprising a lubricant composition, wherein the motor
is suitable for a flexible-fuel vehicle or a dual-fuel vehicle and
the lubricant composition comprises at least one ester group
containing polymer having a high polarity.
2: The motor according to claim 1, comprising a compression rate of
at least 10:1.
3: The motor according to claim 1, comprising a fuel injection
pump.
4: The motor according to claim 1, comprising a multi valve.
5: The motor according to claim 1, wherein the motor meets a
requirement of exhaust emission standard Euro 5.
6: The motor according to claim 1, comprising an exhaust gas
recirculation.
7: The motor according to claim 1, comprising a secondary-air
system.
8: The motor according to claim 1, wherein the at least one ester
group containing polymer is a statistical copolymer comprising at
least 7% by weight of dispersing repeat units derived from a
dispersing monomer.
9: The motor according to claim 8, wherein the at least one ester
group containing polymer is a statistical copolymer comprising at
least 7% by weight of dispersing repeat units derived from at least
one heterocyclic vinyl compound.
10: The motor according to claim 1, wherein the at least one ester
group containing polymer is a graft copolymer having an nonpolar
polymer as a graft base and a dispersing monomer as a graft
layer.
11: The motor according to claim 10, wherein the at least one ester
group containing polymer comprises at least one heterocyclic vinyl
compound as the graft layer.
12: The motor according to claim 11 wherein the at least one ester
group containing polymer is the graft copolymer comprising from 0.5
to 10% by weight of dispersing repeat units derived from the at
least one heterocyclic vinyl compound.
13: The motor according to claim 12, wherein the at least one ester
group containing polymer is the graft copolymer comprising from 1
to 5% by weight of dispersing repeat units derived from the at
least one heterocyclic vinyl compound.
14: The motor according to claim 1, wherein the at least one ester
group containing polymer has a --CO--NR.sub.2-- peak of 1689 to
1692 cnf.sup.1 as measured by FTIR spectroscopy.
15: The motor according to claim 1, wherein the at least one ester
group containing polymer is selected from the group consisting of a
polyalkyl (meth)acrylate (PAMA), a polyalkyl fumerate, a polyalkyl
maleate, and a combination thereof.
16: The motor according to claim 1, wherein the at least one ester
group containing polymer has a weight-average molecular weight of
from 10 000 to 600 000 g/mol.
17: The motor according to claim 1, wherein the at least one ester
group containing polymer is a graft copolymer comprising a graft
base obtained by a process comprising polymerizing a monomer
composition comprising: a) from 0 to 40% by weight, based on a
weight of the monomer composition for preparing a nonpolar segment,
of an ethylenically unsaturated ester compound of formula (I):
##STR00005## wherein R is hydrogen or methyl, R.sup.1 is a linear
or branched alkyl radical having 1 to 6 carbon atoms, and R.sup.2
and R.sup.3 are each independently hydrogen or a group of formula
--COOR' in which R' is hydrogen or an alkyl group having 1 to 6
carbon atoms, b) from 5 to 100% by weight, based on the weight of
the monomer composition for preparing the nonpolar segment, of an
ethylenically unsaturated ester compound of formula (II):
##STR00006## wherein R is hydrogen or methyl, R.sup.4 is a linear
or branched alkyl radical having 7 to 15 carbon atoms, and R.sup.5
and R.sup.6 are each independently hydrogen or a group of the
formula --COOR' in which R'' is hydrogen or an alkyl group having 7
to 15 carbon atoms, c) from 0 to 80% by weight, based on the weight
of the monomer composition for preparing the nonpolar segment, of
an ethylenically unsaturated ester compound of formula (III):
##STR00007## wherein R is hydrogen or methyl, R.sup.7 is a linear
or branched alkyl radical having 16 to 30 carbon atoms, and R.sup.8
and R.sup.9 are each independently hydrogen or a group of formula
--COOR''' in which R''' is hydrogen or an alkyl group having 16 to
30 carbon atoms, and d) from 0 to 50% by weight, based on the
weight of the monomer composition for preparing the hydrophobic
segments, of a comonomer.
18: The motor according to claim 1, wherein the at least one ester
group containing polymer comprises at least one heterocyclic vinyl
compound selected from the group consisting of 2-vinylpyridine,
3-vinylpyridine, 2-methyl-5-vinylpyridine, 3-ethyl-4-vinylpyridine,
2,3-dimethyl-5-vinylpyridine, vinylpyrimidine, vinylpiperidine,
9-vinylcarbazole, 3-vinylcarbazole, 4-vinylcarbazole,
1-vinylimidazole, N-vinylimidazole, 2-methyl-1-vinylimidazole,
N-vinylpyrrolidone, 2-vinylpyrrolidone, N-vinylpyrrolidine,
3-vinylpyrrolidine, N-vinylcaprolactam, N-vinylbutyrolactam,
vinyloxolane, vinylfuran, vinylthiophene, vinylthiolane, a
vinylthiazole and a hydrogenated vinylthiazole, a vinyloxazole, a
hydrogenated vinyloxazole, and a combination thereof.
19: The motor according to claim 1, wherein the lubricant
composition comprises at least one additional additive which is not
a polymer comprising an ester group having a high polarity.
20: The motor as claimed in claim 19, wherein the at least one
additive is a viscosity index improver, a pour point improver, a
dispersant, a detergent, a defoamer, a corrosion inhibitor, an
antioxidant, an antiwear additive, an extreme pressure additive, a
friction modifier, or a combination thereof.
21: The motor as claimed in claim 20, wherein the antiwear
additive, the extreme pressure additive, or both is selected from
the group consisting of a phosphorous compound, a compound
comprising sulfur and phosphorous, a compound comprising sulfur and
nitrogen, a sulfur compound comprising elemental sulfur and
3/4S-sulfurized hydrocarbon, a sulfurized glyceride and a fatty
acid ester, an overbased sulfonate, a chlorine compound, graphite,
molybdenum disulfide, and a combination thereof.
22: A process for producing an emulsion stabilizer in a lubricant,
comprising: contacting the lubricant with a polymer comprising an
ester group having a high polarity.
Description
[0001] The present application relates to a motor having improved
properties. Furthermore the present invention describes a use of
polymers to improve the emulsion stability of lubricants.
[0002] Fuels are nowadays generally obtained from fossil sources.
However, these resources are limited, so that replacements are
being sought. Therefore, interest is rising in renewable raw
materials which can be used to produce fuels.
[0003] Alternate fuels for transportation, such as methanol,
ethanol, etc. have been studied by the automotive industry for a
number of years. While such fuels offer some advantages of reduced
engine emissions, their use is accompanied by a number of
deficiencies and limitations which must be addressed if they are to
become viable alternatives to gasoline.
[0004] In view of the declining ecological quality and decreasing
world crude oil reserves, the use of pure bio alcohols, such as
ethanol (E100) or methanol (M100) has been an important target in
many countries. However, many issues, ranging from different
combustion characteristic to corrosion of seal materials, have been
reported as hindrances to the use of bio alcohols as a replacement
for fossil gasoline. Another major obstacle is the high amount of
water formed by the combustion process or being present based on
the production process of the alcohol in comparison to conventional
gasoline.
[0005] The water formed during combustion, along with alcohol which
bypasses the piston rings or is carried away by the blow-by gases,
tends to accumulate in the oil.
[0006] The alcohol and water may accumulate in the lubricating oil
resulting from the use of such alternate fuels increase corrosion
and wear problems in engines using such alternate fuels, especially
alcohol.
[0007] The problems mentioned above depend of the type of use of
the passenger car. Using the car on very short range circles lead
to very critical problems resulting in short time lubricant
changes. Furthermore, the issues are more critical to motors having
a high sophisticated emission control system and further technical
approaches for fuel savings. The more sophisticated the motor the
more sensitive the motor on lubricant decline, e.g. based on undue
water content.
[0008] Lubricant decline, especially high water content and phase
separation have detrimental effects on various properties of the
motor. These are especially critical for motors having Flex Fuel
compatibility. High water content usually may cause problems
regarding cold start and cold run characteristics of the motor. In
addition thereto, the life time and the fuel consumption of the
motor are negatively influenced by a high water content of the
lubricant.
[0009] There have been many attempts to date to improve cold start
and cold run characteristics of the motors by engineering
techniques and new facilities. However, these options are connected
with disadvantages based on high costs and the fact that usually
only the latest cars can benefit from such improvements. Therefore,
further opportunities to improve the cold start and cold run
characteristics, the life time and the fuel consumption of the
motor would be helpful.
[0010] The use of ester group containing polymers is known in prior
art, e.g. U.S. Pat. No. 4,290,925 described grafted
polymethacrylates containing N-vinyl-2-pyrrolidone which are useful
for preparing stable emulsions of olefin copolymers.
[0011] U.S. Pat. No. 4,057,623 described copolymers of alkyl
methacrylates and N-vinyl-2-pyrrolidone which are useful for
producing water-in-oil emulsions for cosmetic applications. U.S.
Pat. No. 3,519,565 described copolymers of alkyl methacrylates and
N-vinylthiopyrrolidone which are useful for reducing engine sludge
and varnish.
[0012] In addition thereto GB2307916A discloses that
multifunctional olefinic copolymer viscosity index improver with
dispersant properties in combination with further additives can
improve the emulsion stability of lubricants. However, no hints are
mention with regard to ester group containing polymer having a high
polarity. In addition thereto, no specific motor type has been
disclosed.
[0013] In view of the prior art, it was thus an object of the
present invention to provide a solution which is not limited to new
motor designs and can be applied to existing flex-fuel motors.
Especially the cold start and cold run characteristics of flex-fuel
motors should be improved. Furthermore, the improvement of life
time and fuel consumption is a further object of the present
invention.
[0014] These improvements should be achieved without environmental
drawbacks.
[0015] It was a further object of the invention to provide
additives for lubricating oils which provide improved cold start
and cold run characteristics of flex-fuel motors. In addition
thereto the additive should improve the life time and the fuel
consumption of flex-fuel motors.
[0016] Furthermore, the additives should be producible in a simple
and inexpensive manner, and especially commercially available
components should be used. In this context, they should be
producible on the industrial scale without new plants or plants of
complicated construction being required for this purpose.
[0017] It was a further aim of the present invention to provide an
additive which brings about a multitude of desirable properties in
the lubricant. This can minimize the number of different
additives.
[0018] Furthermore, the additive should not exhibit any adverse
effects on the fuel consumption or the environmental compatibility
of the lubricant.
[0019] Moreover, the additive should improve the emulsion stability
of lubricating oils comprising a high amount of water.
[0020] These objects and also further objects which are not stated
explicitly but are immediately derivable or discernible from the
connections discussed herein by way of introduction are achieved by
a motor having all features of claim 1. Appropriate modifications
to the inventive motor are protected in the claims referring back
to claim 1. With regard to the use, claim 22 provides a solution to
the underlying problem.
[0021] The present invention accordingly provides a motor designed
for Flex Fuel compatibility comprising a lubricant composition,
characterized in that the lubricant composition comprises at least
one ester group containing polymer having a high polarity.
[0022] It is thus possible in an unforeseeable manner to provide a
motor designed for Flex Fuel compatibility having an improved cold
start and cold run characteristics. In addition thereto, the motor
of the present invention shows an enhanced life time and lowered
fuel consumption.
[0023] In addition thereto, the motor of the present invention
enables extended oil change intervals. Thus the motor provides
significant improvements in economic aspects based on lower amounts
of motor oil based on a specific mileage.
[0024] Moreover, the solution presented by the present invention is
not limited to new motor designs and can be applied to existing
flex-fuel motors.
[0025] Furthermore, the motor of the present invention can have a
very high compression without being detrimental effected regarding
the cold start and cold run characteristics and life time and the
fuel consumption of flex-fuel motors.
[0026] Furthermore, the additives used in order to obtain a
lubricant being able to solve the problems mentioned above can be
prepared in a simple and inexpensive manner, and it is possible to
use commercially available components in particular. At the same
time, production is possible on the industrial scale, without new
plants or plants of complex construction being required for that
purpose.
[0027] Furthermore, the polymers for use in accordance with the
invention exhibit a particularly favorable profile of properties.
For instance, the polymers can be configured so as to be
surprisingly shear-stable, such that the lubricants have a very
long service life. In addition, the additive for use in accordance
with the invention may bring about a multitude of desirable
properties in the lubricant. For example, it is possible to produce
lubricants with outstanding low-temperature properties or viscosity
properties, which comprise the present polymers comprising ester
groups. This allows the number of different additives to be
minimized. Furthermore, the present polymers comprising ester
groups are compatible with many additives. This allows the
lubricants to be adjusted to a wide variety of different
requirements.
[0028] Furthermore, the additives for use do not exhibit any
adverse effects on fuel consumption or the environmental
compatibility of the lubricant.
[0029] Surprisingly, present polymers comprising ester groups
improve the emulsion stability of lubricating oils comprising a
high amount of water.
[0030] The present invention provides a new motor designed for Flex
Fuel compatibility. These motors are usually part of flex-fuel
vehicles.
[0031] A flexible-fuel vehicle (FFV) or dual-fuel vehicle
(colloquially called a flex-fuel vehicle) is an alternative fuel
vehicle with an internal combustion engine designed to run on more
than one fuel, usually gasoline blended with either ethanol or
methanol fuel, and both fuels are stored in the same common tank.
Flex-fuel engines are capable of burning any proportion of the
resulting blend in the combustion chamber as fuel injection and
spark timing are adjusted automatically according to the actual
blend detected by electronic sensors. Flex-fuel vehicles are
distinguished from bi-fuel vehicles, where two fuels are stored in
separate tanks and the engine runs on one fuel at a time, for
example, compressed natural gas (CNG), liquefied petroleum gas
(LPG), or hydrogen.
[0032] Though technology exists to allow ethanol FFVs to run on any
mixture of gasoline and ethanol, from pure gasoline up to 100%
ethanol (E100), North American and European flex-fuel vehicles are
optimized to run on a maximum blend of 15% gasoline with 85%
anhydrous ethanol (called E85 fuel). This limit in the ethanol
content is set to reduce ethanol emissions at low temperatures and
to avoid cold starting problems during cold weather, at
temperatures lower than 11.degree. C. (52.degree. F.). The alcohol
content is reduced during the winter in regions where temperatures
fall below 0.degree. C. (32.degree. F.) to a winter blend of E70 in
the U.S. or to E75 in Sweden from November until March. Brazilian
flex fuel vehicles are optimized to run on any mix of E20-E25
gasoline and up to 100% hydrous ethanol fuel (E100). The Brazilian
flex vehicles are built-in with a small gasoline reservoir for cold
starting the engine when temperatures drop below 15.degree. C.
(59.degree. F.).
[0033] Preferably, the motor of the present invention is designed
to fuels comprising at least 5%, especially at least 10%,
particularly 20%, more especially at least 50% and more preferably
at least 80% by volume of alcohol, e.g. methanol and/or ethanol.
Furthermore, the motor of the present invention is preferably
designed to fuels comprising at least 5%, especially at least 10%,
particularly 20%, more especially at least 50% and more preferably
at least 80% by volume of gasoline.
[0034] Preferably, the motor comprises a compression of at least
10:1, more preferably at least 12:1.
[0035] According to a special aspect of the present invention, the
motor may comprise a fuel injection pump.
[0036] Unforeseeable advantages can be achieved by a motor
comprising a multi valve technique.
[0037] Furthermore, the motor of the present invention may comprise
an exhaust gas recirculation and/or a secondary-air system.
[0038] Preferably, the motor comprises an engine management for
optimization of the fuel injection and the spark timing.
[0039] Preferred motor of the present invention meet the
requirements of exhaust emission standard Euro 5, more preferably
EURO 6 as defined in Directive No. 715/2007/EC.
[0040] The motor of the present invention comprises a lubricant
composition including at least one ester group containing polymer
having a high polarity.
[0041] Polymers comprising ester groups are understood in the
context of the present invention to mean polymers obtainable by
polymerizing monomer compositions which comprise ethylenically
unsaturated compounds having at least one ester group, which are
referred to hereinafter as ester monomers. Accordingly, these
polymers contain ester groups as part of the side chain. These
polymers include especially polyalkyl (meth)acrylates (PAMA),
polyalkyl fumarates and/or polyalkyl maleates.
[0042] Ester monomers are known per se. They include especially
(meth)acrylates, maleates and fumarates, which may have different
alcohol radicals. The expression "(meth)acrylates" encompasses
methacrylates and acrylates, and mixtures of the two. These
monomers are widely known.
[0043] The polymer comprising ester groups comprises preferably at
least 40% by weight, more preferably at least 60% by weight,
especially preferably at least 80% by weight and most preferably at
least 90% by weight of repeat units derived from ester
monomers.
[0044] Polymers usable in accordance with the invention have a high
polarity. Consequently, the polymer may be a statistical copolymer
comprising a high amount of dispersing repeat units being derived
from a dispersing monomer. Preferably, the statistical copolymer
comprises at least 7%, more preferably at least 9% by weight of
dispersing repeat units being derived from a dispersing monomer. In
addition thereto, the polymer may be a graft copolymer having an
nonpolar polymer as graft base and an dispersing monomer as graft
layer. Surprising improvements can be achieved with graft
copolymers preferably comprising 0.5 to 10% by weight, especially
0.8 to 7% by weight, more preferably 1 to 5% by weight of
dispersing repeat units being derived from at least one dispersing
monomer, preferably a heterocyclic vinyl compound.
[0045] The term "repeat unit" is widely known in the technical
field. The present polymers can preferably be obtained by means of
free-radical polymerization of monomers. This opens up double bonds
to form covalent bonds. Accordingly, the repeat unit arises from
the monomers used.
[0046] Dispersing monomers are understood to mean especially
monomers with functional groups, for which it can be assumed that
polymers with these functional groups can keep particles,
especially soot particles, in solution (cf. R. M. Mortier, S. T.
Orszulik (eds.): "Chemistry and Technology of Lubricants", Blackie
Academic & Professional, London, 2.sup.nd ed. 1997). These
include especially monomers which have boron-, phosphorus-,
silicon-, sulfur-, oxygen- and nitrogen-containing groups,
preference being given to oxygen- and nitrogen-functionalized
monomers.
[0047] The nonpolar graft base may comprise a small proportion of
dispersing repeat units, which is preferably less than 20% by
weight, more preferably less than 10% by weight and most preferably
less than 5% by weight, based on the weight of the nonpolar graft
base. In a particularly appropriate configuration, the nonpolar
graft base comprises essentially no dispersing repeat units.
[0048] The nonpolar graft base of the polymer comprising ester
groups may have 5 to 100% by weight, especially 20 to 98% by
weight, preferably 30 to 95 and most preferably 70 to 92% by weight
of repeat units derived from ester monomers having 7 to 15 carbon
atoms in the alcohol radical.
[0049] In a particular aspect, the nonpolar graft base of the
polymer comprising ester groups may have 0 to 80% by weight,
preferably 0.5 to 60% by weight, more preferably 2 to 50% by weight
and most preferably 5 to 20% by weight of repeat units derived from
ester monomers having 16 to 40 carbon atoms in the alcohol
radical.
[0050] In addition, the nonpolar graft base of the polymer
comprising ester groups may have 0 to 40% by weight, preferably 0.1
to 30% by weight and more preferably 0.5 to 20% by weight of repeat
units derived from ester monomers having 1 to 6 carbon atoms in the
alcohol radical.
[0051] The nonpolar graft base of the polymer comprising ester
groups comprises preferably at least 40% by weight, more preferably
at least 60% by weight, especially preferably at least 80% by
weight and most preferably at least 90% by weight of repeat units
derived from ester monomers.
[0052] Mixtures from which the graft base of the useful polymers
comprising ester groups or the statistical polymers are obtainable
may contain 0 to 40% by weight, especially 0.1 to 30% by weight and
more preferably 0.5 to 20% by weight of one or more ethylenically
unsaturated ester compounds of the formula (I)
##STR00001##
in which R is hydrogen or methyl, R.sup.1 is a linear or branched
alkyl radical having 1 to 6 carbon atoms, R.sup.2 and R.sup.3 are
each independently hydrogen or a group of the formula --COOR' in
which R' is hydrogen or an alkyl group having 1 to 6 carbon
atoms.
[0053] Examples of component (I) include
(meth)acrylates, fumarates and maleates which derive from saturated
alcohols, such as methyl (meth)acrylate, ethyl (meth)acrylate,
n-propyl (meth)acrylate, iso-propyl (meth)acrylate, n-butyl
(meth)acrylate, tert-butyl (meth)acrylate and pentyl
(meth)acrylate, hexyl (meth)acrylate; cycloalkyl (meth)acrylates
such as cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate;
(meth)acrylates which derive from unsaturated alcohols, such as
2-propynyl (meth)acrylate, allyl (meth)acrylate and vinyl
(meth)acrylate.
[0054] The compositions to be polymerized to prepare the graft base
or the statistical polymers preferably contain 5 to 100% by weight,
preferably 10 to 98% by weight and especially preferably 20 to 95%
by weight of one or more ethylenically unsaturated ester compounds
of the formula (II)
##STR00002##
in which R is hydrogen or methyl, R.sup.4 is a linear or branched
alkyl radical having 7 to 15 carbon atoms, R.sup.5 and R.sup.6 are
each independently hydrogen or a group of the formula --COOR'' in
which R'' is hydrogen or an alkyl group having 7 to 15 carbon
atoms.
[0055] Examples of component (II) include:
(meth)acrylates, fumarates and maleates which derive from saturated
alcohols, such as 2-ethylhexyl (meth)acrylate, heptyl
(meth)acrylate, 2-tert-butylheptyl (meth)acrylate, octyl
(meth)acrylate, 3-isopropylheptyl (meth)acrylate, nonyl
(meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate,
5-methylundecyl (meth)acrylate, dodecyl (meth)acrylate,
2-methyldodecyl (meth)acrylate, tridecyl (meth)acrylate,
5-methyltridecyl (meth)acrylate, tetradecyl (meth)acrylate,
pentadecyl (meth)acrylate; (meth)acrylates which derive from
unsaturated alcohols, for example oleyl (meth)acrylate; cycloalkyl
(meth)acrylates, such as 3-vinylcyclohexyl (meth)acrylate, bornyl
(meth)acrylate; and the corresponding fumarates and maleates.
[0056] In addition, preferred monomer compositions for preparing
the graft base or the statistical polymers comprise 0 to 80% by
weight, preferably 0.5 to 60% by weight, more preferably 2 to 50%
by weight and most preferably 5 to 20% by weight of one or more
ethylenically unsaturated ester compounds of the formula (III)
##STR00003##
in which R is hydrogen or methyl, R.sup.7 is a linear or branched
alkyl radical having 16 to 40, preferably 16 to 30, carbon atoms,
R.sup.8 and R.sup.9 are each independently hydrogen or a group of
the formula --COOR''' in which R''' is hydrogen or an alkyl group
having 16 to 40, preferably 16 to 30, carbon atoms.
[0057] Examples of component (III) include (meth)acrylates which
derive from saturated alcohols, such as hexadecyl (meth)acrylate,
2-methylhexadecyl (meth)acrylate, heptadecyl (meth)acrylate,
5-isopropylheptadecyl (meth)acrylate, 4-tert-butyloctadecyl
(meth)acrylate, 5-ethyloctadecyl (meth)acrylate,
3-isopropyloctadecyl (meth)acrylate, octadecyl (meth)acrylate,
nonadecyl (meth)acrylate, eicosyl (meth)acrylate, cetyleicosyl
(meth)acrylate, stearyleicosyl (meth)acrylate, docosyl
(meth)acrylate and/or eicosyltetratriacontyl (meth)acrylate;
cycloalkyl (meth)acrylates such as
2,4,5-tri-t-butyl-3-vinylcyclohexyl (meth)acrylate,
2,3,4,5-tetra-t-butylcyclohexyl (meth)acrylate; and the
corresponding fumarates and maleates.
[0058] The ester compounds with a long-chain alcohol radical,
especially components (II) and (III), can be obtained, for example,
by reacting (meth)acrylates, fumarates, maleates and/or the
corresponding acids with long-chain fatty alcohols, which generally
gives a mixture of esters, for example (meth)acrylates with
different long-chain alcohol radicals. These fatty alcohols include
Oxo Alcohol.RTM. 7911, Oxo Alcohol.RTM. 7900, Oxo Alcohol.RTM.
1100; Alfol.RTM. 610, Alfol.RTM. 810, Lial.RTM. 125 and Nafol.RTM.
types (Sasol); Alphanol.RTM. 79 (ICI); Epal.RTM. 610 and Epal.RTM.
810 (Afton); Linevol.RTM. 79, Linevol.RTM. 911 and Neodol.RTM. 25E
(Shell); Dehydad.RTM., Hydrenol.RTM. and Lorol.RTM. types (Cognis);
Acropol.RTM. 35 and Exxal.RTM. 10 (Exxon Chemicals); Kalcol.RTM.
2465 (Kao Chemicals).
[0059] Among the ethylenically unsaturated ester compounds, the
(meth)acrylates are particularly preferred over the maleates and
fumarates, i.e. R.sup.2, R.sup.3, R.sup.5, R.sup.6, R.sup.8 and
R.sup.9 of the formulae (I), (II) and (III) are each hydrogen in
particularly preferred embodiments.
[0060] The weight ratio of ester monomers of the formula (II) to
the ester monomers of the formula (III) may be within a wide range.
The ratio of ester compounds of the formula (II) which have 7 to 15
carbon atoms in the alcohol radical to the ester compounds of the
formula (III) which have 16 to 40 carbon atoms in the alcohol
radical is preferably in the range from 50:1 to 1:30, more
preferably in the range from 10:1 to 1:3, especially preferably 5:1
to 1:1.
[0061] In addition, the monomer mixture for preparing the graft
base or the statistical polymers may comprise ethylenically
unsaturated monomers which can be copolymerized with the
ethylenically unsaturated ester compounds of the formulae (I), (II)
and/or (III).
[0062] The preferred comonomers include
vinyl halides, for example vinyl chloride, vinyl fluoride,
vinylidene chloride and vinylidene fluoride; styrene, substituted
styrenes having an alkyl substituent in the side chain, for example
.alpha.-methylstyrene and .alpha.-ethylstyrene, substituted
styrenes having an alkyl substituent on the ring, such as
vinyltoluene and p-methylstyrene, halogenated styrenes, for example
monochlorostyrenes, dichlorostyrenes, tribromostyrenes and
tetrabromostyrenes; vinyl and isoprenyl ethers; maleic acid and
maleic acid derivatives different from those mentioned under (I),
(II) and (III), for example maleic anhydride, methylmaleic
anhydride, maleimide, methylmaleimide; fumaric acid and fumaric
acid derivatives different from those mentioned under (I), (II) and
(III).
[0063] In addition, monomer mixtures for preparing the graft base
may comprise dispersing monomers.
[0064] The proportion of comonomers is preferably 0 to 50% by
weight, more preferably 0.1 to 40% by weight and most preferably
0.5 to 20% by weight, based on the weight of the monomer
composition for preparing the graft base or the statistical
polymers.
[0065] In addition to the graft base, a preferred polymer usable in
accordance with the invention comprises at least one graft layer
which comprises repeat units derived from dispersing monomers.
[0066] Dispersing monomers have been used for some time for
functionalizing polymeric additives in lubricant oils, and are
therefore known to those skilled in the art (cf. R. M. Mortier, S.
T. Orszulik (eds.): "Chemistry and Technology of Lubricants",
Blackie Academic & Professional, London, 2.sup.nd ed. 1997).
Appropriately, it is possible to use especially heterocyclic vinyl
compounds and/or ethylenically unsaturated, polar ester compounds
of the formula (IV)
##STR00004##
in which R is hydrogen or methyl, X is oxygen, sulfur or an amino
group of the formula --NH-- or --NR.sup.a-- in which R.sup.a is an
alkyl radical having 1 to 40 and preferably 1 to 4 carbon atoms,
R.sup.10 is a radical which comprises 2 to 1000, especially 2 to
100 and preferably 2 to 20 carbon atoms and has at least one
heteroatom, preferably at least two heteroatoms, R.sup.11 and
R.sup.12 are each independently hydrogen or a group of the formula
--COX'R.sup.10' in which X' is oxygen or an amino group of the
formula --NH-- or --NR.sup.a'-- in which R.sup.a' is an alkyl
radical having 1 to 40 and preferably 1 to 4 carbon atoms, and
R.sup.10' is a radical comprising 1 to 100, preferably 1 to 30 and
more preferably 1 to 15 carbon atoms, as dispersing monomers.
[0067] The expression "radical comprising 2 to 1000 carbon" denotes
radicals of organic compounds having 2 to 1000 carbon atoms.
Similar definitions apply for corresponding terms. It encompasses
aromatic and heteroaromatic groups, and alkyl, cycloalkyl, alkoxy,
cycloalkoxy, alkenyl, alkanoyl, alkoxycarbonyl groups, and also
heteroaliphatic groups. The groups mentioned may be branched or
unbranched. In addition, these groups may have customary
substituents. Substituents are, for example, linear and branched
alkyl groups having 1 to 6 carbon atoms, for example methyl, ethyl,
propyl, butyl, pentyl, 2-methylbutyl or hexyl; cycloalkyl groups,
for example cyclopentyl and cyclohexyl; aromatic groups such as
phenyl or naphthyl; amino groups, hydroxyl groups, ether groups,
ester groups and halides.
[0068] According to the invention, aromatic groups denote radicals
of mono- or polycyclic aromatic compounds having preferably 6 to 20
and especially 6 to 12 carbon atoms. Heteroaromatic groups denote
aryl radicals in which at least one CH group has been replaced by N
and/or at least two adjacent CH groups have been replaced by S, NH
or O, heteroaromatic groups having 3 to 19 carbon atoms.
[0069] Aromatic or heteroaromatic groups preferred in accordance
with the invention derive from benzene, naphthalene, biphenyl,
diphenyl ether, diphenylmethane, diphenyldimethylmethane,
bisphenone, diphenyl sulfone, thiophene, furan, pyrrole, triazole,
oxazole, imidazole, isothiazole, isoxazole, pyrazole,
1,3,4-oxadiazole, 2,5-diphenyl-1,3,4-oxadiazole, 1,3,4-thiadiazole,
1,3,4-triazole, 2,5-diphenyl-1,3,4-triazole,
1,2,5-triphenyl-1,3,4-triazole, 1,2,4-oxadiazole,
1,2,4-thiadiazole, 1,2,4-triazole, 1,2,3-triazole,
1,2,3,4-tetrazole, benzo[b]thiophene, benzo[b]furan, indole,
benzo[c]thiophene, benzo[c]furan, isoindole, benzoxazole,
benzothiazole, benzimidazole, benzisoxazole, benzisothiazole,
benzopyrazole, benzothiadiazole, benzotriazole, dibenzofuran,
dibenzothiophene, carbazole, pyridine, bipyridine, pyrazine,
pyrazole, pyrimidine, pyridazine, 1,3,5-triazine, 1,2,4-triazine,
1,2,4,5-triazine, tetrazine, quinoline, isoquinoline, quinoxaline,
quinazoline, cinnoline, 1,8-naphthyridine, 1,5-naphthyridine,
1,6-naphthyridine, 1,7-naphthyridine, phthalazine,
pyridopyrimidine, purine, pteridine or quinolizine, 4H-quinolizine,
diphenyl ether, anthracene, benzopyrrole, benzoxathiadiazole,
benzoxadiazole, benzo-pyridine, benzopyrazine, benzopyrazidine,
benzopyrimidine, benzotriazine, indolizine, pyridopyridine,
imidazopyrimidine, pyrazinopyrimidine, carbazole, aciridine,
phenazine, benzoquinoline, phenoxazine, phenothiazine, acridizine,
benzopteridine, phenanthroline and phenanthrene, each of which may
also optionally be substituted.
[0070] The preferred alkyl groups include the methyl, ethyl,
propyl, isopropyl, 1-butyl, 2-butyl, 2-methylpropyl, tert-butyl
radical, pentyl, 2-methylbutyl, 1,1-dimethylpropyl, hexyl, heptyl,
octyl, 1,1,3,3-tetramethylbutyl, nonyl, 1-decyl, 2-decyl, undecyl,
dodecyl, pentadecyl and the eicosyl group.
[0071] The preferred cycloalkyl groups include the cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl and the cyclooctyl
group, each of which is optionally substituted with branched or
unbranched alkyl groups.
[0072] The preferred alkanoyl groups include the formyl, acetyl,
propionyl, 2-methylpropionyl, butyryl, valeroyl, pivaloyl,
hexanoyl, decanoyl and the dodecanoyl group.
[0073] The preferred alkoxycarbonyl groups include the
methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, butoxy-carbonyl,
tert-butoxycarbonyl, hexyloxycarbonyl, 2-methylhexyloxycarbonyl,
decyloxycarbonyl or dodecyl-oxycarbonyl group.
[0074] The preferred alkoxy groups include alkoxy groups whose
hydrocarbon radical is one of the aforementioned preferred alkyl
groups.
[0075] The preferred cycloalkoxy groups include cycloalkoxy groups
whose hydrocarbon radical is one of the aforementioned preferred
cycloalkyl groups.
[0076] The preferred heteroatoms which are present in the R.sup.10
radical include oxygen, nitrogen, sulfur, boron, silicon and
phosphorus, preference being given to oxygen and nitrogen.
[0077] The R.sup.10 radical comprises at least one, preferably at
least two, preferentially at least three, heteroatoms.
[0078] The R.sup.10 radical in ester compounds of the formula (IV)
preferably has at least 2 different heteroatoms. In this case, the
R.sup.10 radical in at least one of the ester compounds of the
formula (IV) may comprise at least one nitrogen atom and at least
one oxygen atom.
[0079] Examples of ethylenically unsaturated, polar ester compounds
of the formula (IV) include aminoalkyl (meth)acrylates, aminoalkyl
(meth)acrylamides, hydroxyalkyl (meth)acrylates, heterocyclic
(meth)acrylates and/or carbonyl-containing (meth)acrylates.
[0080] The hydroxyalkyl (meth)acrylates include [0081]
2-hydroxypropyl (meth)acrylate, [0082] 3,4-dihydroxybutyl
(meth)acrylate, [0083] 2-hydroxyethyl (meth)acrylate, [0084]
3-hydroxypropyl (meth)acrylate, [0085] 2,5-dimethyl-1,6-hexanediol
(meth)acrylate and [0086] 1,10-decanediol (meth)acrylate.
[0087] Appropriate carbonyl-containing (meth)acrylates include, for
example, [0088] 2-carboxyethyl (meth)acrylate, [0089] carboxymethyl
(meth)acrylate, [0090] oxazolidinylethyl (meth)acrylate, [0091]
N-(methacryloyloxy)formamide, [0092] acetonyl (meth)acrylate,
[0093] mono-2-(meth)acryloyloxyethyl succinate, [0094]
N-(meth)acryloylmorpholine, [0095]
N-(meth)acryloyl-2-pyrrolidinone, [0096]
N-(2-(meth)acryloyloxyethyl)-2-pyrrolidinone, [0097]
N-(3-(meth)acryloyloxypropyl)-2-pyrrolidinone, [0098]
N-(2-(meth)acryloyloxypentadecyl)-2-pyrrolidinone, [0099]
N-(3-(meth)acryloyloxyheptadecyl)-2-pyrrolidinone and [0100]
N-(2-(meth)acryloyloxyethyl)ethyleneurea. [0101]
2-Acetoacetoxyethyl (meth)acrylate
[0102] The heterocyclic (meth)acrylates include [0103]
2-(1-imidazolyl)ethyl (meth)acrylate, [0104] 2-(4-morpholinyl)ethyl
(meth)acrylate and [0105]
1-(2-(meth)acryloyloxyethyl)-2-pyrrolidone.
[0106] Of particular interest are additionally aminoalkyl
(meth)acrylates and aminoalkyl (meth)acrylatamides, for example
[0107] dimethylaminopropyl (meth)acrylate, [0108]
dimethylaminodiglykol (meth)acrylate, [0109] dimethylaminoethyl
(meth)acrylate, [0110] dimethylaminopropyl (meth)acrylamide, [0111]
3-diethylaminopentyl(meth)acrylate and [0112]
3-dibutylaminohexadecyl (meth)acrylate.
[0113] In addition, it is possible to use phosphorus-, boron-
and/or silicon-containing (meth)acrylates to prepare the polar
segments D, such as [0114] 2-(dimethylphosphato)propyl
(meth)acrylate, [0115] 2-(ethylenephosphito)propyl (meth)acrylate,
[0116] dimethylphosphinomethyl (meth)acrylate, [0117]
dimethylphosphonoethyl (meth)acrylate, [0118] diethyl(meth)acryloyl
phosphonate, [0119] dipropyl(meth)acryloyl phosphate,
2-(dibutylphosphono)ethyl (meth)acrylate, [0120]
2,3-butylene(meth)acryloylethyl borate, [0121]
methyldiethoxy(meth)acryloylethoxysilane, [0122]
diethylphosphatoethyl (meth)acrylate.
[0123] According to a very preferred embodiment heterocyclic vinyl
compounds are used as dispersing monomers. Surprisingly, the
heterocyclic vinyl compounds show improved properties in view of
other dispersing monomers.
[0124] The preferred heterocyclic vinyl compounds include
2-vinylpyridine, 3-vinylpyridine, 2-methyl-5-vinylpyridine,
3-ethyl-4-vinylpyridine, 2,3 dimethyl-5-vinylpyridine,
vinylpyrimidine, vinylpiperidine, 9-vinylcarbazole,
3-vinylcarbazole, 4-vinylcarbazole, 1-vinylimidazole,
N-vinylimidazole, 2-methyl-1-vinylimidazole, N-vinylpyrrolidone,
2-vinylpyrrolidone, N-vinylpyrrolidine, 3-vinylpyrrolidine,
N-vinylcaprolactam, N-vinylbutyrolactam, vinyloxolane, vinylfuran,
vinylthiophene, vinylthiolane, vinylthiazoles and hydrogenated
vinylthiazoles, vinyloxazoles and hydrogenated vinyloxazoles,
particular preference being given to using N-vinylimidazole and
N-vinylpyrrolidone for functionalization.
[0125] The monomers detailed above can be used individually or as a
mixture.
[0126] Of particular interest are especially polymers which
comprise ester groups and are obtained using 2-hydroxypropyl
methacrylate, 2-hydroxyethyl methacrylate,
mono-2-methacryloyloxyethyl succinate,
N-(2-methacryloyloxyethyl)ethyleneurea, 2-acetoacetoxyethyl
methacrylate, 2-(4-morpholinyl)ethyl methacrylate,
dimethylaminodiglycol methacrylate, dimethylaminoethyl methacrylate
and/or dimethylaminopropylmethacrylamide.
[0127] Special improvements can be achieved with ester groups
comprise polymers being obtained using N-vinyl-2-pyrrolidine and/or
N-vinyl-2-pyrrolidone.
[0128] In addition to the dispersing monomers, a composition for
preparing the graft layer may also comprise non-dispersing monomers
which have been detailed above. These include especially
ethylenically unsaturated ester compounds of the formulae (I), (II)
and/or (III).
[0129] The proportion of dispersing repeat units, based on the
weight of the polymers comprising ester groups, is preferably in
the range from 0.5% by weight to 20% by weight, more preferably in
the range from 1.5% by weight to 15% by weight and most preferably
in the range from 2.5% by weight to 10% by weight. At the same
time, these repeat units preferably form a segment-like structure
within the polymer comprising ester groups, such that preferably at
least 70% by weight, more preferably at least 80% by weight, based
on the total weight of the dispersing repeat units, are part of a
graft layer.
[0130] The present invention describes polymers which preferably
have a high oil solubility. The term "oil-soluble" means that a
mixture of a base oil and a polymer comprising ester groups is
preparable without macroscopic phase formation, which has at least
0.1% by weight, preferably at least 0.5% by weight, of the
polymers. The polymer may be present in dispersed and/or dissolved
form in this mixture. The oil solubility depends especially on the
proportion of the lipophilic side chains and on the base oil. This
property is known to those skilled in the art and can be adjusted
readily for the particular base oil via the proportion of
lipophilic monomers.
[0131] Of particular interest, among others, are polymers which
comprise ester groups and preferably have a weight-average
molecular weight M.sub.w in the range from 7500 to 1 000 000 g/mol,
more preferably 10 000 to 600 000 g/mol and most preferably 15 000
to 80 000 g/mol.
[0132] The number-average molecular weight M.sub.n may preferably
be in the range from 5000 to 800 000 g/mol, more preferably 7500 to
500 000 g/mol and most preferably 10 000 to 80 000 g/mol.
[0133] According to a special embodiment of the present invention,
the ester group containing polymer, preferably a
polyalkyl(meth)acrylat may have a weight-average molecular weight
M.sub.w in the range from 2000 to 1 000 000 g/mol, especially from
20 000 to 800 000 g/mol, more preferably 40 000 to 500 000 g/mol
and most preferably 60 000 to 250 000 g/mol.
[0134] According to a further aspect of the present invention, the
ester group containing polymer, preferably a polyalkyl(meth)acrylat
may have a number average molecular weight M.sub.n in the range
from 2 000 to 100 000 g/mol, especially from 4 000 to 60 000 g/mol
and most preferably 5 000 to 30 000 g/mol.
[0135] Polymers having a high molecular weight are especially
useful as viscosity index improvers. Polymers having a low
molecular weight are especially useful as pour point depressants
and flow improvers.
[0136] Additionally appropriate are polymers which comprise ester
groups and whose polydispersity index M.sub.w/M.sub.n is in the
range from 1 to 5, more preferably in the range from 1.05 to 4. The
number-average and weight-average molecular weights can be
determined by known processes, for example gel permeation
chromatography (GPC).
[0137] According to a preferred embodiment of the present
invention, the ester group containing polymer has a
--CO--NR.sub.2-peak in the range of 1689 to 1697 cm.sup.-1, more
preferably in the range of 1689 to 1692 cm.sup.1 as measured by
FTIR spectroscopy (25.degree. C.)
[0138] The polymer comprising ester groups may have a variety of
structures. Preferably, the polymer may especially be present as a
graft copolymer.
[0139] The polymers comprising ester groups for use in accordance
with the invention can be obtained in various ways. A preferred
process consists in free-radical graft copolymerization which is
known per se, wherein, for example, a nonpolar graft base is
obtained in a first step, onto which dispersing monomers are
grafted in a second step.
[0140] Therefore, according to a preferred embodiment, the ester
group containing polymer preferably is a graft copolymer having an
nonpolar alkyl (meth)acrylate polymer as graft base and an
dispersing monomer as graft layer.
[0141] Customary free-radical polymerization, which is especially
suitable for preparing graft copolymers, is detailed in K.
Matyjaszewski, T. P. Davis, Handbook of Radical Polymerization,
Wiley Interscience, Hoboken 2002. In general, a polymerization
initiator and a chain transferer are used for that purpose.
[0142] The usable initiators include the azo initiators widely
known in the technical field, such as AIBN and
1,1-azobiscyclohexanecarbonitrile, and also peroxy compounds such
as methyl ethyl ketone peroxide, acetylacetone peroxide, dilauryl
peroxide, tert-butyl per-2-ethylhexanoate, ketone peroxide,
tert-butyl peroctoate, methyl isobutyl ketone peroxide,
cyclohexanone peroxide, dibenzoyl peroxide, tert-butyl
peroxybenzoate, tert-butyl peroxyisopropyl-carbonate,
2,5-bis(2-ethylhexanoylperoxy)-2,5-dimethylhexane, tert-butyl
peroxy-2-ethylhexanoate, tert-butyl
peroxy-3,5,5-trimethylhexanoate, dicumyl peroxide,
1,1-bis(tert-butylperoxy)cyclohexane,
1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, cumyl
hydroperoxide, tert-butyl hydroperoxide,
bis(4-tert-butylcyclohexyl) peroxydicarbonate, mixtures of two or
more of the aforementioned compounds with one another, and mixtures
of the aforementioned compounds with compounds which have not been
mentioned but can likewise form free radicals. Suitable chain
transferers are in particular oil-soluble mercaptans, for example
n-dodecyl mercaptan or 2-mercaptoethanol, or else chain transferers
from the class of the terpenes, for example terpinolene.
[0143] The polymerization may be carried out at standard pressure,
reduced pressure or elevated pressure. The polymerization
temperature too is uncritical. However, it is generally in the
range of -20.degree.-200.degree. C., preferably
50.degree.-150.degree. C. and more preferably
80.degree.-130.degree. C.
[0144] The polymerization may be carried out with or without
solvent. The term solvent is to be understood here in a broad
sense. The solvent is selected according to the polarity of the
monomers used, preference being given to using 100N oil, relatively
light gas oil and/or aromatic hydrocarbons, for example toluene or
xylene.
[0145] In addition to the ester group containing polymer the
lubricant used in the motor of the present invention includes base
oil. Preferred base oils include especially mineral oils, synthetic
oils and natural oils.
[0146] Mineral oils are known per se and commercially available.
They are generally obtained from mineral oil or crude oil by
distillation and/or refining and optionally further purification
and finishing processes, the term mineral oil including in
particular the higher-boiling fractions of crude or mineral oil. In
general, the boiling point of mineral oil is higher than
200.degree. C., preferably higher than 300.degree. C., at 5000 Pa.
The production by low-temperature carbonization of shale oil,
coking of bituminous coal, distillation of brown coal with
exclusion of air, and also hydrogenation of bituminous or brown
coal is likewise possible. Accordingly, mineral oils have,
depending on their origin, different proportions of aromatic,
cyclic, branched and linear hydrocarbons.
[0147] In general, a distinction is drawn between paraffin-base,
naphthenic and aromatic fractions in crude oils or mineral oils, in
which the term paraffin-base fraction represents longer-chain or
highly branched isoalkanes, and naphthenic fraction represents
cycloalkanes. In addition, mineral oils, depending on their origin
and finishing, have different fractions of n-alkanes, isoalkanes
having a low degree of branching, known as mono-methyl-branched
paraffins, and compounds having heteroatoms, in particular O, N
and/or S, to which a degree of polar properties are attributed.
However, the assignment is difficult, since individual alkane
molecules may have both long-chain branched groups and cycloalkane
radicals, and aromatic parts. For the purposes of the present
invention, the assignment can be effected to DIN 51 378, for
example. Polar fractions can also be determined to ASTM D 2007.
[0148] The proportion of n-alkanes in preferred mineral oils is
less than 3% by weight, the fraction of O-, N- and/or S-containing
compounds less than 6% by weight. The fraction of the aromatics and
of the mono-methyl-branched paraffins is generally in each case in
the range from 0 to 40% by weight. In one interesting aspect,
mineral oil comprises mainly naphthenic and paraffin-base alkanes
which have generally more than 13, preferably more than 18 and most
preferably more than 20 carbon atoms. The fraction of these
compounds is generally 60% by weight, preferably 80% by weight,
without any intention that this should impose a restriction. A
preferred mineral oil contains 0.5 to 30% by weight of aromatic
fractions, 15 to 40% by weight of naphthenic fractions, 35 to 80%
by weight of paraffin-base fractions, up to 3% by weight of
n-alkanes and 0.05 to 5% by weight of polar compounds, based in
each case on the total weight of the mineral oil.
[0149] An analysis of particularly preferred mineral oils, which
was effected by means of conventional processes such as urea
separation and liquid chromatography on silica gel, shows, for
example, the following constituents, the percentages relating to
the total weight of the particular mineral oil used:
n-alkanes having approx. 18 to 31 carbon atoms: 0.7-1.0%, slightly
branched alkanes having 18 to 31 carbon atoms: 1.0-8.0%, aromatics
having 14 to 32 carbon atoms: 0.4-10.7%, iso- and cycloalkanes
having 20 to 32 carbon atoms: 60.7-82.4%, polar compounds:
0.1-0.8%, loss: 6.9-19.4%.
[0150] An improved class of mineral oils (reduced sulfur content,
reduced nitrogen content, higher viscosity index, lower pour point)
results from hydrogen treatment of the mineral oils
(hydroisomerization, hydrocracking, hydrotreatment,
hydrofinishing). In the presence of hydrogen, this essentially
reduces aromatic components and builds up naphthenic
components.
[0151] Valuable information with regard to the analysis of mineral
oils and a list of mineral oils which have a different composition
can be found, for example, in T. Mang, W. Dresel (eds.):
"Lubricants and Lubrication", Wiley-VCH, Weinheim 2001; R. M.
Mortier, S. T. Orszulik (eds.): "Chemistry and Technology of
Lubricants", Blackie Academic & Professional, London, 2.sup.nd
ed. 1997; or J. Bartz: "Additive fur Schmierstoffe", Expert-Verlag,
Renningen-Malmsheim 1994.
[0152] Synthetic oils include organic esters, for example diesters
and polyesters, polyalkylene glycols, polyethers, synthetic
hydrocarbons, especially polyolefins, among which preference is
given to polyalphaolefins (PAOs), silicone oils and perfluoroalkyl
ethers. In addition, it is possible to use synthetic base oils
originating from gas to liquid (GTL), coal to liquid (CTL) or
biomass to liquid (BTL) processes. They are usually somewhat more
expensive than the mineral oils, but have advantages with regard to
their performance.
[0153] Natural oils are animal or vegetable oils, for example
neatsfoot oils or jojoba oils.
[0154] Base oils for lubricant oil formulations are divided into
groups according to API (American Petroleum Institute). Mineral
oils are divided into group I (non-hydrogen-treated) and, depending
on the degree of saturation, sulfur content and viscosity index,
into groups II and III (both hydrogen-treated). PAOs correspond to
group IV. All other base oils are encompassed in group V.
[0155] These lubricant oils may also be used as mixtures and are in
many cases commercially available.
[0156] The concentration of the polymers comprising ester groups in
the lubricant oil composition is preferably in the range of 0.01 to
30% by weight, more preferably in the range of 0.1-20% by weight
and most preferably in the range of 0.5-10% by weight, based on the
total weight of the composition.
[0157] In addition to the polymers comprising ester groups for use
in accordance with the invention, the lubricant oil compositions
detailed here may also comprise further additives. These additives
include VI improvers, pour point improvers and DI additives
(dispersants, detergents, defoamers, corrosion inhibitors,
antioxidants, antiwear and extreme pressure additives, friction
modifiers).
[0158] The additionally usable VI improvers include especially
polyalkyl (meth)acrylates having 1 to 30 carbon atoms in the
alcohol group (PAMA; partly N/O-functional with advantageous
additional properties as dispersants, antiwear additives and/or
friction modifiers), which differ from the copolymers detailed in
claim 1, and poly(iso)butenes (PIB), fumarate-olefin copolymers,
styrene-maleate copolymers, hydrogenated styrene-diene copolymers
(HSD) and olefin copolymers (OCP).
[0159] The pour point improvers include especially polyalkyl
(meth)acrylates (PAMA) having 1 to 30 carbon atoms in the alcohol
group.
[0160] Compilations of VI improvers and pour point improvers for
lubricant oils are also detailed in T. Mang, W. Dresel (eds.):
"Lubricants and Lubrication", Wiley-VCH, Weinheim 2001: R. M.
Mortier, S. T. Orszulik (eds.): "Chemistry and Technology of
Lubricants", Blackie Academic & Professional, London, 2nd ed.
1997; or J. Bartz: "Additive fur Schmierstoffe", Expert-Verlag,
Renningen-Malmsheim 1994.
[0161] Appropriate dispersants include poly(isobutylene)
derivatives, e.g. poly(isobutylene)succinimides (PIBSIs);
ethylene-propylene oligomers with N/O functionalities.
[0162] The preferred detergents include metal-containing compounds,
for example phenoxides; salicylates; thio-phosphonates, especially
thiopyrophosphonates, thio-phosphonates and phosphonates;
sulfonates and carbonates. As metals, these compounds may comprise
especially calcium, magnesium and barium. These compounds may be
used preferably in neutral or overbased form.
[0163] Of particular interest are additionally defoamers, which are
in many cases divided into silicone-containing and silicone-free
defoamers. The silicone-containing defoamers include linear
poly(dimethylsiloxane) and cyclic poly(dimethylsiloxane). The
silicone-free defoamers which may be used are in many cases
polyethers, for example poly(ethylene glycol) or tributyl
phosphate.
[0164] In a particular embodiment, the inventive lubricant oil
compositions may comprise corrosion inhibitors. These are in many
cases divided into antirust additives and metal
passivators/deactivators. The antirust additives used may, inter
alia, be sulfonates, for example petroleumsulfonates or (in many
cases overbased) synthetic alkylbenzenesulfonates, e.g.
dinonylnaphthenesulfonates; carboxylic acid derivatives, for
example lanolin (wool fat), oxidized paraffins, zinc naphthenates,
alkylated succinic acids, 4-nonylphenoxy-acetic acid, amides and
imides (N-acylsarcosine, imidazoline derivatives);
amine-neutralized mono- and dialkyl phosphates; morpholine,
dicyclohexylamine or diethanolamine. The metal
passivators/deactivators include benzotriazole, tolyltriazole,
2-mercaptobenzothiazole, dialkyl-2,5-dimercapto-1,3,4-thiadiazole;
N,N'-disalicylideneethylenediamine,
N,N'-disalicylidenepropylenediamine; zinc dialkyldithiophosphates
and dialkyl dithiocarbamates.
[0165] A further preferred group of additives is that of
antioxidants. The antioxidants include, for example, phenols, for
example 2,6-di-tert-butylphenol (2,6-DTB), butylated hydroxytoluene
(BHT), 2,6-di-tert-butyl-4-methylphenol,
4,4'-methylenebis(2,6-di-tert-butylphenol); aromatic amines,
especially alkylated diphenylamines, N-phenyl-1-naphthylamine
(PNA), polymeric 2,2,4-trimethyldihydroquinone (TMQ); compounds
containing sulfur and phosphorus, for example metal
dithiophosphates, e.g. zinc dithiophosphates (ZnDTP), "OOS
triesters"=reaction products of dithiophosphoric acid with
activated double bonds from olefins, cyclopentadiene,
norbornadiene, .alpha.-pinene, polybutene, acrylic esters, maleic
esters (ashless on combustion); organosulfur compounds, for example
dialkyl sulfides, diaryl sulfides, polysulfides, modified thiols,
thiophene derivatives, xanthates, thioglycols, thioaldehydes,
sulfur-containing carboxylic acids; heterocyclic sulfur/nitrogen
compounds, especially dialkyldimercaptothiadiazoles,
2-mercaptobenzimidazoles; zinc and methylene
bis(dialkyldithiocarbamate); organophosphorus compounds, for
example triaryl and trialkyl phosphites; organocopper compounds and
overbased calcium- and magnesium-based phenolates and
salicylates.
[0166] The preferred antiwear (AW) and extreme pressure (EP)
additives include phosphorus compounds, for example trialkyl
phosphates, triaryl phosphates, e.g. tricresyl phosphate,
amine-neutralized mono- and dialkyl phosphates, ethoxylated mono-
and dialkyl phosphates, phosphites, phosphonates, phosphines;
compounds containing sulfur and phosphorus, for example metal
dithiophosphates, e.g. zinc C.sub.3-12dialkyldithiophosphates
(ZnDTPs), ammonium dialkyldithiophosphates, antimony
dialkyldithiophosphates, molybdenum dialkyldithiophosphates, lead
dialkyldithiophosphates, "OOS triesters"=reaction products of
dithiophosphoric acid with activated double bonds from olefins,
cyclopentadiene, norbornadiene, .alpha.-pinene, polybutene, acrylic
esters, maleic esters, triphenylphosphorothionate (TPPT); compounds
containing sulfur and nitrogen, for example zinc bis(amyl
dithiocarbamate) or methylenebis(di-n-butyl dithiocarbamate);
sulfur compounds containing elemental sulfur and
H.sub.2S-sulfurized hydrocarbons (diisobutylene, terpene);
sulfurized glycerides and fatty acid esters; overbased sulfonates;
chlorine compounds or solids such as graphite or molybdenum
disulfide.
[0167] A further preferred group of additives is that of friction
modifiers. The friction modifiers used may include mechanically
active compounds, for example molybdenum disulfide, graphite
(including fluorinated graphite), poly(trifluoroethylene),
polyamide, polyimide; compounds which form adsorption layers, for
example long-chain carboxylic acids, fatty acid esters, ethers,
alcohols, amines, amides, imides; compounds which form layers
through tribochemical reactions, for example saturated fatty acids,
phosphoric acid and thiophosphoric esters, xanthogenates,
sulfurized fatty acids; compounds which form polymer-like layers,
for example ethoxylated dicarboxylic acid partial esters, dialkyl
phthalates, methacrylates, unsaturated fatty acids, sulfurized
olefins or organometallic compounds, for example molybdenum
compounds (molybdenum dithiophosphates and molybdenum
dithiocarbamates MoDTC) and their combinations with ZnDTPs,
copper-containing organic compounds.
[0168] Some of the additives detailed above may fulfill multiple
functions. ZnDTP, for example, is primarily an antiwear additive
and extreme pressure additive, but also has the character of an
antioxidant and corrosion inhibitor (here: metal
passivator/deactivator).
[0169] The additives detailed above are described in more detail,
inter alia, in T. Mang, W. Dresel (eds.): "Lubricants and
Lubrication", Wiley-VCH, Weinheim 2001; J. Bartz: "Additive fur
Schmierstoffe", Expert-Verlag, Renningen-Malmsheim 1994; R. M.
Mortier, S. T. Orszulik (eds.): "Chemistry and Technology of
Lubricants", Blackie Academic & Professional, London, 2.sup.nd
ed. 1997.
[0170] Preferred lubricant oil compositions have a viscosity,
measured at 40.degree. C. to ASTM D 445, in the range of 10 to 120
mm.sup.2/s, more preferably in the range of 20 to 100 mm.sup.2/s.
The kinematic viscosity KV.sub.100 measured at 100.degree. C. is
preferably at least 5.0 mm.sup.2/s, more preferably at least 5.2
mm.sup.2/s and most preferably at least 5.4 mm.sup.2/s.
[0171] In a particular aspect of the present invention, preferred
lubricant oil compositions have a viscosity index determined to
ASTM D 2270 in the range of 100 to 400, more preferably in the
range of 125 to 325 and most preferably in the range of 150 to
250.
[0172] Furthermore, lubricant compositions for the use in the motor
of the present invention may preferably comprise a High Temperature
High Shear (HTHS) viscosity of at least 2.4 mPas, more preferably
at least 2.6 mPas as measured at 150.degree. C. according to ASTM
D4683. According to a further aspect of the present invention the
lubricant may preferably comprise a high temperature high shear of
at most 10 mPas, especially at most 7 mPas more preferably at most
5 mPas as measured at 100.degree. C. according to ASTM D4683. The
difference between the High Temperature High Shear (HTHS)
viscosities as measure at 100.degree. C. and 150.degree. C.
HTHS.sub.100-HTHS.sub.150 preferably comprises at most 4 mPas,
especially at most 3.3 mPas and more preferably at most 2.5 mPas.
The ratio of the High Temperature High Shear (HTHS) viscosity
measured at 100.degree. C. (HTHS.sub.100) to the High Temperature
High Shear (HTHS) viscosity measured at 150.degree. C.
(HTHS.sub.150-HTHS.sub.100/HTHS.sub.150 preferably comprises at
most at most 2.0 mPas, especially at most 1.9 mPas. High
Temperature High Shear (HTHS) viscosity can be determined according
to D4683.
[0173] In addition thereto, the lubricant useful as component of
the present motor may comprises a high shear stability index (SSI).
According to a useful embodiment of the present invention, the
shear stability index (SSI) as measured according to ASTM D2603
Ref. B (12.5 minutes sonic treatment) could preferably amount to 35
or less, more preferably to 20 or less. Preferably, lubricants
comprising a shear stability index (SSI) as measured according to
DIN 51381 (30 cycles Bosch-pump) of at most 5, especially at most 2
and more preferably at most 1 could be used.
[0174] The lubricant useful for the present invention can
preferably be designed to meet the requirements of the SAE
classifications as specified in SAE J300. E.g. the requirements of
the viscosity grades 0W, 5W, 10W, 15W, 20W, 25W, 20, 30, 40, 50,
and 60 (single-grade) and 0W-40, 10W-30, 10W-60, 15W-40, 20W-20 and
20W-50 (multi-grade) could be adjusted.
[0175] Preferably, the lubricant composition meets the gasoline
engine oil quality specifications ILSAC's GF-5, especially the
emulsion retention bench test stating that a mixture of formulated
oil (80%), E85 fuel (10%), and water (10%) must form a stable
emulsion for at least 24 hours after mixing at 0 and 25.degree.
C.
[0176] Consequently, the lubricant of the present invention may
contain at least about 1%, especially at least 5%, particularly at
least 10% by volume of water. Astonishingly, such high amounts of
water do not impart unduly high lowering of the motor
characteristics such as life time, cold run performance and fuel
consumption.
[0177] Surprisingly, the present invention provides a lubricant
forming highly stable emulsions with water. Therefore, a specific
aspect of the present invention is the use of polymers having a
high polarity as emulsion stabilizer in lubricants.
[0178] The invention will be illustrated in detail hereinafter with
reference to examples and comparative examples, without any
intention that this should impose a restriction. Unless otherwise
specified, the percentages are weight percent.
PREPARATION EXAMPLES
List of Abbreviations
[0179] MMA=methyl methacrylate N1214MA=methacrylic acid ester of
NAFOL1214 L125MA=methacrylic acid ester of LIAL125
A1618MA=methacrylic acid ester of ALFOL 1620
DMAEMA=dimethylaminoethyl methacrylate NVP=N-vinyl-2-pyrrolidone
nDDM=n-dodecylmercapton tBPO=t-butylperoctoate
tBPB=t-butylperbenzoate
Comparative Example 1
[0180] 107.5 grams of mineral oil was charged to a four-neck round
glass bottom flask equipped with glass stirrer, condenser and
thermocouple and were heated under an atmosphere of nitrogen to
100.degree. C. A mixture of 500 grams of a L125MA, 8.5 grams of
nDDM and 2 grams of tBPO was added to the round bottom flask via an
addition funnel over the course of two hours. The temperature of
the reaction mixture was maintained at 100.degree. C. throughout
the course of the addition. Following the complete of addition the
mixture, the reaction mixture was held at 100.degree. C. for an
additional 2 hours. Additional mineral oil was added to achieve the
desired concentration of polymer in oil.
Comparative Example 2
[0181] 107.5 grams of mineral oil was charged to a four-neck round
glass bottom flask equipped with glass stirrer, condenser and
thermocouple and were heated under an atmosphere of nitrogen to
100.degree. C. A mixture of 375 grams of N1214MA, 125 grams of MMA,
7.5 grams of nDDM and 2 grams of tBPO was added to the round bottom
flask via an addition funnel over the course of two hours. The
temperature of the reaction mixture was maintained at 100.degree.
C. throughout the course of the addition. Following the complete of
addition the mixture, the reaction mixture was held at 100.degree.
C. for an additional 2 hours. Additional mineral oil was added to
achieve the desired concentration of polymer in oil.
Comparative Example 3
[0182] 111 grams of mineral oil was charged to a four-neck round
glass bottom flask equipped with glass stirrer, condenser and
thermocouple and were heated under an atmosphere of nitrogen to
100.degree. C. A mixture of 385 grams of N1214MA, 100 grams of MMA,
15 grams of DMAEMA, 4.0 grams of nDDM and 2 grams of tBPO was added
to the round bottom flask via an addition funnel over the course of
two hours. The temperature of the reaction mixture was maintained
at 100.degree. C. throughout the course of the addition. Following
the complete of addition the mixture, the reaction mixture was held
at 100.degree. C. for an additional 2 hours. Additional mineral oil
was added to achieve the desired concentration of polymer in
oil.
Comparative Example 4
[0183] 112.5 grams of mineral oil was charged to a four-neck round
glass bottom flask equipped with glass stirrer, condenser and
thermocouple and were heated under an atmosphere of nitrogen to
100.degree. C. A mixture of 225 grams of N1214MA, 275 grams of
A1618MA, 5.0 grams of nDDM and 2 grams of tBPO was added to the
round bottom flask via an addition funnel over the course of two
hours. The temperature of the reaction mixture was maintained at
100.degree. C. throughout the course of the addition. Following the
complete of addition the mixture, the reaction mixture was held at
100.degree. C. for an additional 2 hours. Additional mineral oil
was added to achieve the desired concentration of polymer in
oil.
Comparative Example 5
[0184] 325 grams of mineral oil was charged to a four-neck round
glass bottom flask equipped with glass stirrer, condenser and
thermocouple and were heated under an atmosphere of nitrogen to
110.degree. C. A mixture of 415 grams of N1214MA, 70 grams of MMA,
15 grams of NVP and 5.0 grams of tBPO was added to the round bottom
flask via an addition funnel over the course of two hours. The
temperature of the reaction mixture was maintained at 110.degree.
C. throughout the course of the addition. Following the complete of
addition the mixture, the reaction mixture was held at 110.degree.
C. for an additional 2 hours. Additional mineral oil was added to
achieve the desired concentration of polymer in oil.
Example 1
[0185] 325 grams of mineral oil were charged to a four-neck round
glass bottom flask equipped with glass stirrer, condenser and
thermocouple and were heated under an atmosphere of nitrogen to
100.degree. C. A mixture of 485 grams of N1214MA and 3.75 grams of
tBPO was added to the round bottom flask via an addition funnel
over the course of three hours. The temperature of the reaction
mixture was maintained at 100.degree. C. throughout the course of
the addition. Following the complete of addition the mixture, the
reaction mixture was held at 100.degree. C. for an additional 2
hours. The temperature was raised to 130.degree. C. and 15 grams of
NVP was added to the reaction mixture with 2 grams of tBPB. The
reaction mixture was held for an additional hour at 130.degree. C.
Additional mineral oil was added to achieve the desired
concentration of polymer in oil.
Example 2
[0186] 325 grams of mineral oil was charged to a four-neck round
glass bottom flask equipped with glass stirrer, condenser and
thermocouple and were heated under an atmosphere of nitrogen to
110.degree. C. A mixture of 415 grams of N1214MA, 70 grams of MMA
and 5.0 grams of tBPO was added to the round bottom flask via an
addition funnel over the course of three hours. The temperature of
the reaction mixture was maintained at 110.degree. C. throughout
the course of the addition. Following the complete of addition the
mixture, the reaction mixture was held at 110.degree. C. for an
additional 2 hours. The temperature was raised to 130.degree. C.
and 15 grams of NVP was added to the reaction mixture with 2 grams
of tBPB. The reaction mixture was held for an additional hour at
130.degree. C. Additional mineral oil was added to achieve the
desired concentration of polymer in oil.
Example 3
[0187] 325 grams of mineral oil was charged to a four-neck round
glass bottom flask equipped with glass stirrer, condenser and
thermocouple and were heated under an atmosphere of nitrogen to
110.degree. C. A mixture of 210 grams of N1214MA, 275 grams of
A1618MA and 7.5 grams of tBPO was added to the round bottom flask
via an addition funnel over the course of three hours. The
temperature of the reaction mixture was maintained at 110.degree.
C. throughout the course of the addition. Following the complete of
addition the mixture, the reaction mixture was held at 110.degree.
C. for an additional 2 hours. The temperature was raised to
130.degree. C. and 15 grams of NVP was added to the reaction
mixture with 2 grams of tBPB. The reaction mixture was held for an
additional hour at 130.degree. C. Additional mineral oil was added
to achieve the desired concentration of polymer in oil.
Example 4
[0188] 325 grams of mineral oil was charged to a four-neck round
glass bottom flask equipped with glass stirrer, condenser and
thermocouple and were heated under an atmosphere of nitrogen to
110.degree. C. A mixture of 320 grams of N1214MA, 160 grams of
L125MA, 5 grams of MMA and 7.5 grams of tBPO was added to the round
bottom flask via an addition funnel over the course of three hours.
The temperature of the reaction mixture was maintained at
110.degree. C. throughout the course of the addition. Following the
complete of addition the mixture, the reaction mixture was held at
110.degree. C. for an additional 2 hours. The temperature was
raised to 130.degree. C. and 25 grams of NVP was added to the
reaction mixture with grams of tBPB. The reaction mixture was held
for an additional hour at 130.degree. C. Additional mineral oil was
added to achieve the desired concentration of polymer in oil.
Example 5
[0189] 325 grams of mineral oil was charged to a four-neck round
glass bottom flask equipped with glass stirrer, condenser and
thermocouple and were heated under an atmosphere of nitrogen to
110.degree. C. A mixture of 475 grams of N1214MA and 7.5 grams of
tBPO was added to the round bottom flask via an addition funnel
over the course of three hours. The temperature of the reaction
mixture was maintained at 110.degree. C. throughout the course of
the addition. Following the complete of addition the mixture, the
reaction mixture was held at 110.degree. C. for an additional 2
hours. The temperature was raised to 130.degree. C. and 25 grams of
NVP was added to the reaction mixture with 2 grams of tBPB. The
reaction mixture was held for an additional hour at 130.degree. C.
Additional mineral oil was added to achieve the desired
concentration of polymer in oil.
Example 6
[0190] 325 grams of mineral oil was charged to a four-neck round
glass bottom flask equipped with glass stirrer, condenser and
thermocouple and were heated under an atmosphere of nitrogen to
110.degree. C. A mixture of 450 grams of a N1214MA and 7.5 grams of
tBPO was added to the round bottom flask via an addition funnel
over the course of three hours. The temperature of the reaction
mixture was maintained at 110.degree. C. throughout the course of
the addition. Following the complete of addition the mixture, the
reaction mixture was held at 110.degree. C. for an additional 2
hours. The temperature was raised to 130.degree. C. and 50 grams of
NVP was added to the reaction mixture with 2 grams of tBPB. The
reaction mixture was held for an additional hour at 130.degree. C.
Additional mineral oil was added to achieve the desired
concentration of polymer in oil.
Example 7
[0191] 325 grams of mineral oil was charged to a four-neck round
glass bottom flask equipped with glass stirrer, condenser and
thermocouple and heated under an atmosphere of nitrogen to
110.degree. C. A mixture of 425 grams of N1214MA, 25 grams of MMA,
50 grams of NVP and 5.0 grams of tBPO was added to the round bottom
flask via an addition funnel over the course of two hours. The
temperature of the reaction mixture was maintained at 110.degree.
C. throughout the course of the addition. Following the complete of
addition the mixture, the reaction mixture was held at 110.degree.
C. for an additional 2 hours. Additional mineral oil was added to
achieve the desired concentration of polymer in oil.
Use Examples
Emulsion Stability
[0192] 1.0 grams of the experimental additive was mixed with 99.0
grams of an API Group I oil mixture having a kinematic viscosity of
5.4 cSt at 100.degree. C. 80 mL of this blend of additive and oil
was transferred to a 100 mL graduated cylinder to which 10 mL of an
ethanol/heptane (85/15 v/v) solution and 10 mL of water was added.
This mixture was rapidly stirred for 5 minutes and allowed to stand
at room temperature for 24 hours. A passing test was defined as the
lack of a water layer after the end of the 24 hour period.
FTIR Spectroscopy
[0193] The additives were placed between silver chloride plates and
sandwiched into a Teflon cell holder. Using a Thermo Nicolet Avatar
370 FT-IR, the additives were scanned 32 times at a resolution of 4
cm.sup.-1. A background scan was taken followed by the sample scan.
The peak location of the disubstituted amine, --CO--NR.sub.2--, is
observed as a shoulder peak to the strong carbonyl, C.dbd.O,
stretching peak.
TABLE-US-00001 TABLE 1 Additive compositions Comparative Examples
Comparative Example Number 1 2 3 4 5 Amount MMA -- 25 20 -- 14 of
N1214MA -- 75 77 45 83 mono- L125MA 100 -- -- -- -- mer A1618MA --
-- -- 55 -- DMAEMA -- -- 3 -- -- NVP -- -- -- -- 3 % polymer 88 70
70 65 65 Mw, g/mol 25,000 40,000 100,000 75,000 90,000 FTIR
Analysis, cm.sup.-1 n.o. n.o. n.o. n.o. 1696 Emulsion Stability
Fail Fail Fail Fail Fail
TABLE-US-00002 TABLE 2 Additive compositions Examples Example
Number 1 2 3 4 5 Amount of MMA -- 14 -- 1 -- monomer N1214MA 97 83
42 64 88 L125MA -- -- -- 32 -- A1618MA -- -- 55 -- 6 DMAEMA -- --
-- -- -- NVP 3 3 3 3 5 % polymer 55 57 57 58 57 Mw, g/mol 220,000
150,000 120,000 115,000 155,000 FTIR Analysis, cm.sup.-1 1691 1691
1691 1691 1690 Emulsion Stability Pass Pass Pass Pass Pass Examples
Example Number 6 7 Amount of MMA -- 5 monomer N1214MA 90 85 L125MA
A1618MA -- -- DMAEMA -- -- NVP 10 10 % polymer 57 65 Mw, g/mol
300,000 54,000 FTIR Analysis, cm.sup.-1 1696 1695 Emulsion
Stability Pass Pass
[0194] The results in Tables 1 and 2 demonstrate that lubricant
compositions containing copolymers as described by the invention
are capable of improving the emulsion retention of a lubricant oil
formulation.
[0195] In addition thereto, the properties of the present polymers
have been tested using modified emulsion stability test.
[0196] The results in Table 3 were obtained when the concentration
of example additive was varied.
TABLE-US-00003 TABLE 3 Additional results from modified emulsion
stability test* Amount of Emulsion Example Additive Stability 6
0.15 Pass 9 0.15 Pass
[0197] The results in Table 4 were obtained when example additives
were mixed with SAE 5W-30 engine oil.
TABLE-US-00004 TABLE 4 Additional results from modified emulsion
stability test* Amount of Emulsion Example Additive Stability 8
0.15 Pass 9 0.15 Pass
* * * * *