U.S. patent application number 10/114283 was filed with the patent office on 2003-02-20 for viscosity index improver and lube oil containing the same.
This patent application is currently assigned to Sanyo Chemical Industries, Ltd.. Invention is credited to Ota, Yoshihisa, Yuki, Tsuyoshi.
Application Number | 20030036488 10/114283 |
Document ID | / |
Family ID | 18961158 |
Filed Date | 2003-02-20 |
United States Patent
Application |
20030036488 |
Kind Code |
A1 |
Yuki, Tsuyoshi ; et
al. |
February 20, 2003 |
Viscosity index improver and lube oil containing the same
Abstract
A viscosity index improver, which comprises a polymer (A) having
a solubility parameter of 8.6-9.4, a crystallizing initiation
temperature of equal to or less than -15.degree. C., and a steric
hindrance factor (F) of 0-13, said factor F being defined by the
following equation: F=4X+Y (1) wherein X and Y represent the total
numbers of atoms at the 6th position and the 7th position,
respectively, in the side chains; said polymer (A) having a Mw of
5,000-2,000,000 and comprising units of at least one monomer
selected from the group consisting of: (a) a monomer represented by
the general formula: CH.sub.2.dbd.C(R.sup.0)--COO--(AO).sub.n--R
(2) wherein R.sup.0 is hydrogen atom or methyl group, R is a
C.sub.1-40alkyl group, n is 0 or an integer of 1-20 giving 0-10 on
average, A is an alkylene group containing 2-4 carbon atoms, plural
A's in case of n being at least 2 are the same or different, and
the polyoxyalkylene moiety (AO).sub.n in case of the plural A's
being different comprises random-wise or block-wise distributed
oxyalkylene groups; (b) an alkyl alkenyl ether; (c) an alkenyl
carboxylate; and (d) a nitrogen-containing unsaturated monomer. The
suitable monomers, 2-decyl-tetradecyl methacrylate and
2-decyl-tetradecyl acrylate compose the polymer (A), are also
described.
Inventors: |
Yuki, Tsuyoshi; (Kyoto,
JP) ; Ota, Yoshihisa; (Kyoto, JP) |
Correspondence
Address: |
ARMSTRONG,WESTERMAN & HATTORI, LLP
1725 K STREET, NW.
SUITE 1000
WASHINGTON
DC
20006
US
|
Assignee: |
Sanyo Chemical Industries,
Ltd.
Kyoto-shi
JP
J
|
Family ID: |
18961158 |
Appl. No.: |
10/114283 |
Filed: |
April 3, 2002 |
Current U.S.
Class: |
508/469 ;
508/470; 508/471; 508/472 |
Current CPC
Class: |
C10N 2030/02 20130101;
C10M 149/10 20130101; C10N 2060/06 20130101; C10M 149/04 20130101;
C10M 2217/02 20130101; C10M 2217/028 20130101; C10N 2070/00
20130101; C10M 145/14 20130101; C10M 2209/04 20130101; C10M 2209/06
20130101; C10N 2020/01 20200501; C10M 2209/062 20130101; C10M
171/00 20130101; C10N 2070/02 20200501; C10N 2020/04 20130101; C10N
2020/071 20200501; C10N 2040/046 20200501; C10N 2040/08 20130101;
C10N 2040/25 20130101; C10N 2040/04 20130101; C10M 2217/022
20130101; C10M 2217/023 20130101; C10M 2209/084 20130101; C10N
2040/02 20130101; C10N 2040/042 20200501 |
Class at
Publication: |
508/469 ;
508/470; 508/471; 508/472 |
International
Class: |
C10M 145/14 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 6, 2001 |
JP |
JP2001-109164 |
Claims
What is claimed as new and desired to be secured by letters patent
is:
1. A viscosity index improver, which comprises a polymer (A) having
a solubility parameter of 8.6-9.4, a crystallizing initiation
temperature of equal to or less than -15.degree. C., and a steric
hindrance factor (F) of 0-13, said factor F being defined by the
following equation: F=4X+Y (1) wherein X and Y represent the total
numbers of atoms at the 6th position and the 7th position,
respectively, in the side chains, counted from the backbone; said
polymer (A) having a weight-average molecular weight of
5,000-2,000,000 and comprising units of at least one monomer
selected from the group consisting of: (a) a monomer represented by
the general formula: 5wherein R.sup.0 is hydrogen atom or methyl
group, R is a C.sub.1-40alkyl group, n is 0 or an integer of 1-20
giving 0-10 on average, A is an alkylene group containing 2-4
carbon atoms, plural A's in case of n being at least 2 are the same
or different, and the polyoxyalkylene moiety (AO).sub.n in case of
the plural A's being different comprises random-wise or block-wise
distributed oxyalkylene groups; (b) an alkyl alkenyl ether; (c) an
alkenyl carboxylate; and (d) a nitrogen-containing unsaturated
monomer.
2. The improver of claim 1, wherein said polymer (A) contains units
of said monomer (a), said monomer (b) or said monomers (a) and (b)
in an amount of at least 30% by weight, with or without 0-45% by
weight of units of said monomer (c), 0-12% by weight of units of
said monomer (d) and 0-20% by weight of units of another
monomer.
3. The improver of claim 1, wherein said polymer (A) is a copolymer
(A1), comprising units of at least one monomer (a1) represented by
the general formula (2) wherein R is a branched alkyl group
containing 16-40 carbon atoms.
4. The improver of claim 3, wherein said copolymer (A1) comprises
5-90% by weight of units of said monomer (a1) , and 10-60% by
weight of units of an alkyl acrylate or methacrylate (a2)
containing 1-4 carbon atoms in the alkyl group, with or without
0-85% by weight of units of at least one selected from the group
consisting of an alkyl acrylate or methacrylate (a3) containing
8-15 carbon atoms in the alkyl group and a straight-chain alkyl
acrylate or methacrylate (a4) containing 16-18 carbon atoms in the
alkyl group.
5. The improver of claim 4, wherein said copolymer (A1) further
comprises 0.1-10% by weight of units of said monomer (d).
6. The improver of claim 5, wherein said monomer (d) is at least
one selected from the group consisting of dimethylaminoethyl
acrylate, diethylaminoethyl acrylate, morpholinoethyl acrylate, and
corresponding methacrylates.
7. A viscosity index improver, which comprises a copolymer (A11)
having a weight-average molecular weight of 5,000-2,000,000,
comprising 5-90% by weight of units of at least one monomer (a11)
and 5-95% by weight of units of at least one alkyl acrylate or
methacrylate other than said monomer (a11): said monomer (a11)
being capable of providing a homopolymer having a crystallizing
initiation temperature of equal to or less than 5.degree. C. and
represented by the general formula: 6wherein R.sup.0 is hydrogen
atom or methyl group, R is a branched alkyl group containing 20-40
carbon atoms, n is 0 or an integer of 1-20 giving 0-10 on average,
A is an alkylene group containing 2-4 carbon atoms, plural A's in
case of n being at least 2 are the same or different, and the
polyoxyalkylene moiety (AO).sub.n in case of the plural A's being
different comprises random-wise or block-wise distributed
oxyalkylene groups.
8. The improver of claim 7, wherein R is represented by the general
formula: 7wherein R.sup.1 and R.sup.2 are the same or different
straight-chain alkyl groups containing 8-18 carbon atoms.
9. The improver of claim 7, wherein said copolymer (A11) has a
solubility parameter of 8.6-9.4, a crystallizing initiation
temperature of equal to or less than -15.degree. C., and a steric
hindrance factor F of 0-13, said factor being defined by the
following equation: F=4X+Y (1) wherein X and Y represent the total
numbers of atoms at the 6th position and the 7th position,
respectively, in the side chains, counted from the backbone.
10. The improver of claim 9, wherein said copolymer (A11) has a
steric hindrance factor F of 0-10.
11. The improver of claim 7, wherein said copolymer (A11) comprises
5-90% by weight of units of said monomer (a11), and 10-60% by
weight of units of an alkyl acrylate or methacrylate (a2)
containing 1-4 carbon atoms in the alkyl group, with or without
0-85% by weight of units of at least one selected from the group
consisting of an alkyl acrylate or methacrylate (a3) containing
8-15 carbon atoms in the alkyl group, a branched alkyl acrylate or
methacrylate (a12) containing 16-19 carbon atoms in the alkyl
group, a straight-chain alkyl acrylate or methacrylate (a4)
containing 16-18 carbon atoms in the alkyl group and a
straight-chain alkyl acrylate or methacrylate (a5) containing 20-40
carbon atoms in the alkyl group.
12. The improver of claim 7, wherein said copolymer (A11) comprises
10-45% by weight of units of 2-decyl-tetradecyl methacrylate,
20-45% by weight of units of methyl methacrylate, and 10-60% by
weight of units of a straight-chain alkyl acrylate or methacrylate
containing 10-18 carbon atoms in the alkyl group.
13. The improver of claim 7, wherein said copolymer (A11) further
comprises 0.1-10% by weight of units of a nitrogen-containing
unsaturated monomer (d).
14. The improver of claim 13, wherein said monomer (d) is at least
one selected from the group consisting of N,N-dimethylaminoethyl
acrylate, N,N-diethylaminoethy i acrylate, morpholinoethyl
acrylate, and corresponding methacrylates.
15. A viscosity improver concentrate, which comprises 10-90% by
weight of said improver of claim 1 and 10-90% by weight of a
diluent.
16. A viscosity improver concentrate, which comprises 10-90% by
weight of said improver of claim 7, and 10-90% by weight of a
diluent.
17. A lube oil composition, which comprises a major amount of a
base oil and 0.5-30% by weight of said improver of claim 1.
18. The composition of claim 17, wherein the base oil has a
kinematic viscosity of 1-15 mm.sup.2/s at 100.degree. C. and a
viscosity index of at least 80.
19. A lube oil composition, which comprises a major amount of a
base oil and 0.5-30% by weight of said improver of claim 7.
20. The composition of claim 19, wherein the base oil has a
kinematic viscosity of 1-15 mm.sup.2/s at 100.degree. C. and a
viscosity index of at least 80 .
21. A compound of 2-decyl-tetradecyl methacrylate.
22. A compound of 2-decyl-tetradecyl acrylate.
23. A homopolymer having a weight-average molecular weight of
5,000-2,000,000, comprises units of a compound selecting from the
group consisting of the compound o t claim 21 and the compound of
claim 22.
24. A copolymer, having a weight-average molecular weight of
5,000-2,000, 000, comprises 5-90% by weight of units of a compound
selecting from the group consisting of the compound of claim 21 and
the compound of claim 22, and 5-95% by weight of units of at least
one monomer selecting from the group consisting of: an alkyl
methacrylate or an alkyl acrylate other than the compound of claim
21 or claim 22; an alkyl alkenyl ether; an alkenyl carboxylate; and
a nitrogen-containing unsaturated monomer.
Description
BACKGROUND OF THE INVENTION
[0001] 1.Field of the Invention
[0002] This invention relates to a viscosity index improver
(hereinafter referred to as VII). More particularly, it relates to
a VII for lube oils, such as engine oils, automatic transmission
fluids (ATF), continuously variable transmission fluids (CVTF),
gear oils and hydrolic fluids.
[0003] 2.Description of the Prior Art
[0004] As VIIs to improve viscosity index (hereinafter referred to
as VI) of lube oils, there have been known heretofore copolymers of
C.sub.1-8alkyl (meth) acrylates (f or instance, U.S. Pat. No.
5,622,924) . The word, "(meth)acrylate" represents acrylate and/or
methacrylate and also "C.sub.1-8alkyl" represents alkyl group
containing 1-18 carbon atoms; and similar expressions are used
hereinafter.
SUMMARY OF THE INVENTION
[0005] It is an object of the present invention to provide a VII
capable of imparting an improved VI to lube oil.
[0006] It is another object of this invention to provide a
viscosity improver concentrate capable of imparting an improved VI
to a lube oil.
[0007] It is still another object of the invention to provide a
lube oil composition having an improved VI.
[0008] It is yet another object of the present invention to provide
a monomer consisting of 2-decyl-tetradecyl methacrylate or
2-decyl-tetradecyl acrylate.
[0009] Briefly, these and other objects of this invention as
hereinafter will become more readily apparent have been attained
broadly by a VII, comprising a polymer (A) or (A11) as follows.
Polymer (A) has a solubility parameter (hereinafter referred to as
SP) of 8.6-9.4, a crystallizing initiation temperature (hereinafter
referred to as Tc) of equal to or less than -15.degree. C. and a
steric hindrance factor F, defined by the following equation (1),
of 0-13.
F=4X+Y (1)
[0010] In the equation (1), X and Y represent the total numbers of
atoms at the 6th position and the 7th position, respectively, in
the side chains, counted from the backbone.
[0011] Polymer (A) comprises units of at least one monomer selected
from the group consisting of an acrylic monomer (hereinafter
referred to as (a)) represented by the following general formula
(2), an alkyl alkenyl ether (hereinafter referred to as (b)), an
alkenyl carboxylate (hereinafter referred to as (c)) and a
nitrogen-containing unsaturated monomer (hereinafter referred to as
(d)). 1
[0012] In the general formula (2), R.sup.0 is hydrogen atom or
methyl group, R is a C.sub.1-40alkyl group, n is 0 or an integer of
1-20 giving 0-10 on average, and A is an C.sub.2-4alkylene
group.
[0013] Polymer (A) is preferably a copolymer (A1), comprising units
of at least one monomer (a1) represented by the general formula (2)
wherein R is a branched C.sub.16-40alkyl group (hereinafter
referred to as R.sup.1).
[0014] Copolymer (A11), in another aspect of this invention,
comprises units of at least one monomer ((a11)) represented by the
general formula (2) wherein R is a branched C.sub.20-40alkyl group
(hereinafter referred to as R.sup.11), and units of at least one
other alkyl (meth)acrylate. Said (meth)acrylate (a11) is capable of
providing a homopolymer having a Tc of equal to or less than
5.degree. C.
[0015] Polymers (A) and (A11) have a weight-average molecular
weight (hereinafter referred to as Mw) of usually
5,000-2,000,000.
[0016] In the above, "polymer" represents copolymer and/or
homopolymer; and such expression is used hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG.1, FIG.2 and FIG.3 show the .sup.1H--NMR spectrogram,
the .sup.13C--NMR spectrogram, and the IR spectrogram of
2-decyl-tetradecyl methacrylate, respectively.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS MONOMERS
COMPOSING THE POLYMER (A)
[0018] The following monomers (a) to (m) compose the polymer
(A).
[0019] (a) Acrylic monomers (hereinafter referred to as (a))
[0020] Monomers (a) are represented by the above-mentioned general
formula (2). In the general formula (2), n is 0 or an integer of
1-20 (preferably 0-10) giving 0-10 (preferably 0-5) on average,
particularly n is 0. Suitable C.sub.2-4 alkylene groups that is
shown "A" in the formula (2), include ethylene, propylene, and
1,2-, 2,3-,1,3-and 1,4-butylene groups, as well as combinations of
two or more of these alkylene groups. Among alkylene groups,
preferred are ethylene, propylene, 1,2-butylene and combinations of
them.
[0021] In case of n is at least 2, the said A is represented as A'.
Plural A's may be the same or different, and the polyoxy-alkylene
moiety (A'O).sub.n in case of the plural A's being different can
comprise random-wise and/or block-wise distributed oxyalkylene
groups.
[0022] R.sup.0 is hydrogen atom or methyl group, preferably methyl
group.
[0023] Suitable C.sub.1-40 alkyl groups (R) include, for
example,
[0024] (1) R.sup.1, namely branched C.sub.16-40 alkyl groups;
[0025] (2) C.sub.1-4 alkyl groups, such as methyl, ethyl, n- and
i-propyl, and n-, i-, sec- and t-butyl groups;
[0026] (3) straight-chain and branched-chain C.sub.8-15alkyl
groups, such as n- and i-octyl, 2-ethylhexyl, n- and i-nonyl, n-
and i-decyl, n- and i-dodecyl, 2-methylundecyl, n- and i-tridecyl,
2-methyldodecyl, n- and i-tetradecyl, 2-methyltridecyl, n- and
i-pentadecyl and 2-methyltetradecyl groups;
[0027] (4) straight-chain C.sub.16-19 alkyl groups, such as
n-hexadecyl, n-octadecyl and n-nonadecyl groups;
[0028] (5) straight-chain C.sub.20-40 alkyl groups, such as
n-eicosyl, n-docosyl, n-tetracosyl and n-octacosyl groups; and
[0029] (6) straight-chain and branched C.sub.5-7alkyl groups, such
as n-, i-, sec- and neo-pentyl, n- and i-hexyl 2-methylpentyl and
n- and i-heptyl groups.
[0030] Suitable branched C.sub.16-40 alkyl groups (R.sup.1) have
usually 1-12 branchings, preferably 1 branching. Branched
C.sub.16-40 alkyl groups (R.sup.1) are inclusive of branched
C.sub.20-40 alkyl groups (R.sup.11) and branched C.sub.16-19 alkyl
groups (R.sup.12)
[0031] Illustrative of suitable groups R.sup.11 5are, for
example,
[0032] 1-alkyl groups (e.g., 1-ethyloctadecyl, 1-hexyltetradecyl,
1-octyldodecyl, 1-butyleicosyl, 1-hexyloctadecyl, 1-octylhexadecyl,
1-decyltetradecyl, 1-undecyl-tridecyl groups, etc.);
[0033] 2-alkyl groups (e.g., 2-hexyltetradecyl, 2-ethyloctadecyl,
2-decyltetradecyl, 2-undecyltridecyl, 2-octylhexadecyl,
2-hexyloctadecyl, 2-dodecylhexadecyl, 2-tridecylpentadecyl,
2-decyloctadecyl, 2-tetradecyloctadecyl, 2-hexadecyloctadecyl,
2-tetradecyleicosyl and 2-hexadecyleicosyl groups, etc.);
[0034] 3-alkyl to 34-alkyl groups (e.g., 3-alkyl, 4-alkyl, 5-alkyl,
32-alkyl, 33-alkyl, 34-alkyl, etc.); and
[0035] alkyl groups containing one or more branchings (e.g., alkyl
groups of oxoalcohols corresponding to propylene oligomers (from
heptamer to undecamer), ethylene/propylene (molar ratio 16/1-1/11)
oligomers, iso-butylene oligomers (from pentamer to octamer),
.alpha.-olefine(C.sub.5-20)oligomers from tetramar to octamer,
etc.).
[0036] Examples of suitable groups R.sup.12 include 2-alkyl groups
(e.g., 2-hexyldecyl, 2-hexylundecyl, 2-octyldecyl, 2-octyldodecyl,
2-butyldodecyl, 2-butyl-tetradecyl, 2-methyloctadecyl,
2-metylhexadecyl groups, etc.).
[0037] Among these groups R.sup.11 and R.sup.12, preferred in
regard of VI and low viscosity even at low temperature are groups
R.sup.11, particularly those of C.sub.20-36. More preferred are
those of C.sub.22-28, especially of C.sub.24. Preferable types in
this regard are 2-alkyl groups, represented by the general formula:
2
[0038] Wherein R.sup.1 and R.sup.2 are the same or different
straight-chain C.sub.8-18 alkyl groups. The most preferred R.sup.1
is a dodecyl group. The most preferred R.sup.2 is a dodecyl
group.
[0039] The most preferred R in the formula (2) is a
2-decyltetradecyl group.
[0040] Suitable acrylic monomers (a) include, for example, monomers
of the general formula (2) wherein R is a branched C.sub.16-40
alkyl group R.sup.1 (hereinafter referred to as (a1)),
C.sub.1-4alkyl (meth)acrylates (hereinafter referred to as (a2)),
C.sub.8-15alkyl (meth)acrylates (hereinafter referred to as (a3)),
straight-chain C.sub.16-18alkyl (meth)acrylates hereinafter
referred to as (a4)), straight-chain C.sub.20-40alkyl
(meth)acrylates (hereinafter referred to as (a5)) and
C.sub.5-7alkyl (meth)acrylates (hereinafter referred to as
(a6)).
[0041] Monomers (a1) include monomers (a11) of the general formula
(2) wherein R is a branched C.sub.20-40 alkyl group R.sup.11 and
monomers (a12) of the general formula (2) wherein R is a branched
C.sub.16-19 alkyl group R.sup.12. Among these, preferred are
monomers (a1), particularly monomers (a11)
[0042] Monomers (a11), having R.sup.11, are capable of providing a
homopolymer having a Tc of equal to or less than 5.degree. C.,
preferably equal to or less than 0.degree. C., more preferably
equal to or less than -15.degree. C. Tc is measured with respect to
a homopolymer prepared by polymerizating a particular monomer under
the following conditions.
[0043] Into a reaction vessel equipped with a stirrer, a heating
and cooling device, a thermometer, a dropping funnel and nitrogen
gas inlet tube, 25 parts of toluene is charged. After the
atmosphere in the vessel is replaced with nitrogen gas, a monomer
solution comprising 100 parts of monomer, 0.3 parts of a dodecyl
mercaptan (hereinafter referred to as DM) that is a chain transfer
agent and 0.5 parts of a 2,2'-azo-bis-(2,4- dimethyl)valeronitrile
(hereinafter reffered to as ADVN) is added dropwise from the
dropping funnel. This addition is made over a period of for 4
hours, at 85.degree. C., in the absence of air. The reaction
mixture is held at 85.degree. C. for a period of 2 hours, so that
the polymerization proceeds well. Thereafter, toluene is evaporated
under reduced pressure, at 130.degree. C., for 3 hours, and a
resultant homopolymer is obtained.
[0044] Illustrative of suitable monomers (a11) are
2-decyltetradecyl methacrylate (Tc=-30.degree. C.),
2-tetradecyloctadecyl methacrylate (Tc=3.degree. C.),
2-octyldecyloxyethyl (meth)acrylate, diethylene glycol
mono-2-decyltetradecylether (meth)acrylate, dipropylene glycol
mono-2-decyltetradecylether (meth)acrylate and dibutylene glycol
mono-2-decyltetradecylether (meth)acrylate. Tc in the parentheses
is Tc of the homopolymer comprises the monomer.
[0045] There may be used two or more of these monomers, for
instance, combinations of (a1) and (a2) with or without (a3)/(a4),
and combinations of (a11) and (a2) with or without at least one of
(a3), (a12), (a4) and (a5).
[0046] (b) Alkyl alkenyl ethers (hereinafter referred to as
(b))
[0047] Suitable monomers (b) include, for example one represented
by the general formula R--O--D, wherein D is a C.sub.2-10
(preferably C.sub.2-4, particularly C.sub.2-3) alkenyl group and R
is a C.sub.1-40 (preferably C.sub.1-30, particularly C.sub.1-20)
alkyl group. Examples of the suitable alkenyl group include vinyl,
(meth)allyl and (iso)propenyl groups. Examples of the alkyl group R
in the general formula include the same alkyl group "R" in the
general formula (2) mentioned above in the said monomer (a).
[0048] Examples of suitable ethers (b) are alkyl vinyl ethers, and
alkyl (meth)allyl ethers. Preferred are methyl vinyl ether, ethyl
vinyl ether, methyl allyl ether and ethyl allyl ether.
[0049] (c) Alkenyl carboxylate (hereinafter referred to as (c))
[0050] Suitable monomers (c) include, for example, ones represented
by the general formula R--COO--D, wherein R and D are the same as
"R" and "D" in the above-mentioned general formula of the monomer
(b). Illustrative of suitable carboxylates (c) are vinyl acetate,
vinyl propionate, vinyl hexanoate, vinyl 2-ethylhexanoate and vinyl
n-octanoate. Preferred are vinyl acetate and vinyl propionate.
[0051] (d) Nitrogen-containing unsaturated monomers (hereinafter
referred to as (d))
[0052] Suitable monomers (d) are inclusive of amino-containing
monomers (d1), amide-containing monomers (d2), and nitro-containing
monomers (d3).
[0053] Suitable monomers (d1) include primary, secondary and
tertiary amino-containing aliphatic monomers, for example,
[0054] mono-C.sub.3-6 alkenyl amines (e.g., (di) (meth) allyl
amines, crotyl amine, etc.), amino-containing acrylic monomers, for
instance, amino-C.sub.2-6alkyl(meth)acrylates (e.g., aminoethyl and
aminopropyl (meth)acrylate, etc.) mono- and di- C.sub.1-4
alkyl-amino C.sub.2-6 alkyl (meth)acrylates (e.g.,
(di)methyl-aminoethyl, (di)ethylaminoethyl, (di)butylaminoethyl and
(di)methylaminopropyl (meth)acrylate, etc.);
[0055] primary, secondary and tertiary amino-containing aromatic
monomers, for example, aminostyrenes (e.g., (dimethyl)aminostyrene,
phenylaminostyrene, etc.), (meth)acryl-amides (e.g., 4-and
2-phenylaminophenyl (meth)acryl-amide, etc.);
[0056] amino-containing heterocyclic monomers, for example,
morpholino C.sub.2-4alkyl (meth)acrylates, (e.g., morpholinoethyl
(meth) acrylate, etc.), vinylpyridines, (e.g., 4-and
2-vinylpyridine, N-vinylpyrrole and N-vinyl(thio)-pyrrolidone,
etc.).
[0057] Suitable amide-containing monomers (d2) include
[0058] (meth)acrylamide; and
[0059] N-vinyl-carbonamides (e.g., N-vinyl-formamide,
N-vinyl-acetoamide, N-vinyl-n-and i-propionamide,
N-vinylhydroxyacetoamide, etc.).
[0060] Examples of nitro-containing monomers (d3) are
nitrostyrenes, (e.g., 4-nitrostyrene, etc.).
[0061] Among monomers (d), preferred are monomers (d1). More
preferred are tertiary amino-containing acrylic monomers,
particularly dimethylaminoethyl, diethylaminoethyl and
morpholinoethyl (meth)acrylates.
[0062] (e) Aliphatic hydrocarbon vinyl monomers (hereinafter
refereed to as (e))
[0063] Suitable monomers (e) include, f or example, C .sub.2-20
alkenes (e. g. , ethylene, propylene, butene, isobutylene, pentene,
heptene, diisobutylene, octene, dodecen, octadecene, etc.), and
C.sub.4-12 alkadienes (e.g., butadiene, isoprene, 1, 4-pentadiene,
1, 6-heptadiene, 1,7-octadiene, etc.) .
[0064] (f) Alicyclic hydrocarbon vinyl monomers (hereinafter
referred to as (f))
[0065] Suitable monomers (f) include, for example, cyclohexene,
(di)cyclopentadiene, pinene, limonene, indene, vinylcyclohexene,
ethylidenebicycloheptene.
[0066] (g) Aromatic hydrocarbon vinyl monomers (hereinafter
referred to as (g)
[0067] Suitable monomers (g) include, for example, styrene,
.alpha.-methylstyrene, vinyltoluene, 2,4-dimethylstyrene,
4-ethylstyrene, 4-isopropylstyrene, 4-butylstyrene,
4-phenylstyrene, 4-cyclohexylstyrene, 4-benzylstyrene,
4-crotylbenzene and 2-vinylnaphthalene.
[0068] (h) Vinyl ketones (hereinafter referred to as (h))
[0069] Suitable monomers (h) include, for example, C.sub.1-10 alkyl
or C.sub.1-8 aryl vinylketones (e.g., methylvinylketone,
ethylvinylketone, phenylvinylketone, etc.).
[0070] (i) Vinyl monomers having epoxy group (hereinafter referred
to as (i) )
[0071] Suitable monomers (i) include, for example,
glycidyl(meta)acrylate and glycidyl(meta)allyl ether.
[0072] (j) Vinyl monomers having halogen (hereinafter referred to
as (j))
[0073] Suitable monomers (j) include, for example, vinyl chloride,
vinyl bromide, vinylidene chloride, (meta)allyl chloride, styrene
halide(e.g. dichlorostyrene, etc.).
[0074] (k) Esters consisting of unsaturated polycarboxylic acid
(hereinafter referred to as (k))
[0075] Suitable monomers(k) include, for example, alkyl, cycloalkyl
or aralkyl esters of unsaturated polycarboxylic acid. Among these
esters, preferred are , C.sub.1-20 alkyl diester cnnsisting of
unsaturated dicarboxylic acid such as maleic acid, fumaric acid,
itaconic acid, (e.g., dimethylmaleate, dimethylfumarate,
diethylmaleate, dioctylmaleate, etc.). (l) vinyl monomers having
hydroxyl group (hereinafter referred to as (l))
[0076] Suitable monomers (l) include, for example,
[0077] aromatic vinyl monomer having hydroxyl group (e.g.,
p-hydroxystyrene, etc.), hydroxy-C.sub.2-6 alkyl(meth)acrylate
(e.g., 2-hydroxyethyl(meth)acrylate, 2- or
3-hydroxypropyl(meth)acrylate, etc.);
[0078] mono- or di-hydroxy-C.sub.1-4 alkyl substituted
(meth)acrylamide (e.g., N,N- dihydroxymethyl(meth)acrylamide,
N,N-dihydroxypropyl (meth)acrylamide,
N,N-di-2-hydroxybutyl(meth)acrylamide, etc.);
[0079] vinyl alcohol, that is obtained by hydrolysis of vinyl
acetate;
[0080] C.sub.3-12 alkenol (e.g., (meth)allylalcohol, crotylalcohol,
iso-crotylalcohol, 1-octenol, 1-undecenol, etc.);
[0081] C.sub.4-12 alkenediol (e.g., 1-butene-3-ol, 2-butene-1-ol,
2-butene-1,4-diol, etc.);
[0082] hydroxy-C.sub.1-6 alkyl-C.sub.3-10 alkenyl ether (e.g.,
2-hydroxyethyl-propenyl ether, etc.);
[0083] polyvalent alcohol having 3-8 hydroxy groups;
[0084] alkane polyol;
[0085] its intra- or inter-molecular dehydration product; and
[0086] C.sub.3-10 alkenyl ether and (meth) acrylate, of a
saccharide, for example, glycerol, pentaerythritol, sorbitol,
sorbitan, diglycerol, and sucrose (e.g., sucrose (meth)allyl ether,
etc.).
[0087] (m) vinyl monomers having carboxylic acid group (hereinafter
referred to as (m))
[0088] Suitable monomers (m) include,
[0089] vinyl monomers having monocarboxylic acid group, for
instance, unsaturated monocarboxylic acid (e.g., (meth)acrylic
acid, .alpha.-methyl(meth)acrylic acid, crotonic acid, cinnamic
acid, etc.);
[0090] mono C.sub.1-8 alkyl ester of unsaturated dicarboxylic acid
(e.g., mono-alkyl maleate, mono-alkyl fumarate, mono-alkyl
itaconate, etc.); and
[0091] vinyl monomers having dicarboxylic acid group, (e.g., maleic
acid, fumaric acid, itaconic acid, citraconic acid, etc.).
[0092] When VII is required property of a detergent, it is
preferred that the polymer (A) comprises units of (d). When VII is
not required property of a detergent, the monomer of (d) is not
necessary to comprise the polymer (A).
POLYMER (A)
[0093] Several kinds of monomers that compose (A) include,
preferably, at least (a), at least (b) or at least (a) and (b). The
sum amount of (a) and (b), preferably at least 30%, more preferably
50-100%, particularly 80-100% against total amount of monomer(s) to
be used for synthesis (A) (% stands for weight percentages
hereafter, unless it is specifically mentioned otherwise). With
regard to the ratio of (a) and (b), (a)/(b) is generally
30-100/0-70, preferably 50-100/0-50. If (c) and/or (d) is used
together with (a) and/or (b), the amount of (c) preferably at most
45%, particularly at most 40%, and the amount of (d), preferably at
most 12%, particularly at most 10%, against total amount of several
monomers to be used for synthesis (A) .
[0094] If (d) to (m) is employed by requirement, together with the
monomers (a) to (c) for synthesis (A), the sum amount, if plural
kinds of monomers (d) to (m) are employed, or the amount if single
monomer selected from the group consisting of (d) to (m) is
employed, is preferably 0-20%, particularly 0.1-10% against total
weight of monomers ((a) to (m)) to be used for synthesis (A).
[0095] The polymer (A1) contains generally 5-90%, preferably
10-80%, particularly 10-60%, most particularly 10-45% of units of
(a1), and contain generally 10-60%, preferably 20-50%, particulary
20-45% of units of (a2). (A1) contains generally 0-85%, preferably
10-70%, particularly 10-60% of units of (a3) and/or (a4) (in
particular, such monomers having 10-18 carbon atoms). (A1) contains
preferably 0-20%, more preferably 0-10% of units of (a5) and /or
(a6).
[0096] In addition to (A1), example of the polymer (A) contains
5-20% of units of (a2), 30-70% of units of (a3), and 5-20% of units
of (a4) Other examples of the polymer (A) are homopolymers
comprises the monomer (b), such as homopolymer of methyl vinyl
ether, homopolymer of the monomer that has general formula (2) and
R is branched-alkyl group having 4-8 carbon atoms, and homopolymer
of ethylene glycol mono-2-ethylhexyl-methac- rylate, and the
like.
[0097] The polymer (A) has a weight average molecular weight (Mw)
of generally 5,000 to 2,000,000, preferably 8,000 to 500,000, more
preferably 10,000 to 250,000. If Mw is 5,000 or more, (A) has
adequate capability of increasing viscosity so that usually oil
dose not need excess amount of (A). If Mw is 2,000,000 or less, (A)
has adequate shear stability. Mw is measured by gel permeation
chromatography using calibration curve of polystyrene.
[0098] The polymer (A) has a SP value of generally 8.6-9.4,
preferably 9.0-9.35, particularly 9.1-9.3. If SP is between the
above range, (A) has an adequate solubility to base oil and also
adequate ability of improving VI. The SP value in the present
invention is one measured by the Fedors method [Polym.Eng.Sci.14
(2) 152, (1974)].
[0099] (A) has a Tc of generally equal to or less than -15.degree.
C., preferably equal to or less than -17.5.degree. C., particularly
-20 to -70.degree. C., more particularly -35 to -70.degree. C. If
Tc is equal to or less than -15.degree. C., (A) does not
crystallize at low temperature, so that (A) has an excellent low
temperature behavior. Tc value is measured using differential
scanning calorimeter "UNIX DSC7" (PERKIN-ELMER Corp.) applying 5 mg
of polymer as a specimen, measuring the crystallizing initiation
temperature (Tc) under cooling from 100 .degree. C. to -45.degree.
C. at a rate of -10.degree. C./min.
[0100] Further, (A) has a steric hindrance factor, F of generally
0-13, preferably 0-12.5, more preferably 0-10, particularly 0-8,
more particularly 0-7. The F is defined the above-mentioned
equation (1). Namely, considering a monomeric unit constituting
polymer (A), X represents the total numbers of atoms at the sixth
position in a side chain from the backbone. Y represents the total
numbers of atoms at the seventh position atom in a side chain. If
monomeric unit has plural side chains, X and Y are counted
respective side chain and added to the total number. F.sup.0 is the
sum of four times X.sup.0, and Y.sup.0. The position is counted
from the backbone (as shown in the following example) that a
particular side chain bonded with, is assigned the number 0, and
goes sequentially to the direction to outside of the particular
side chain. The total number X and also Y are simply the sum of the
atoms, that is, the kind of atom does not affect the total number.
When the polymer (A) is copolymer, F is the average of F.sup.0 of
each monomer unit calculated based on the molar fractions of each
monomer unit in the copolymer. The F briefly expresses degree of
steric hindrance of side chain in the polymer. The greater F means
the more degree of steric hindrance.
[0101] Following is an example of calculating F. A number of the
right shoulder of atoms shows the position of atoms counted from
backbone.
Example Copolymer
2-Decyl-tetradecyl Methacrylate/Methyl Methacrylate=40/60 (molar
ratio)
[0102] 3
[0103] The left-hand side-chain: 2-decyl-tetradecyl methacrylate
residue The total number of atoms at the sixth position =6 (i.e.,
total number of atoms suffixed 6 at their right shoulder) The total
number of atoms at the seventh position =6
F.sup.0=6.times.4+6=30
[0104] The right-hand side-chain: methyl methacrylate residue The
total number of atoms at the sixth position =0 The total number of
atoms at the seventh potion =0
F.sup.0=0.times.4+0=0
[0105] Molar ratio=40:60
F=30.times.0.4+0.times.0.6=12
[0106] If the F is 0-13, steric hindrance around backbone is small.
Consequently, the polymer is easy to come to shrink at low
temperature, and viscosity index becomes larger and viscosity at
low temperature becomes low.
[0107] Means to adjust Mw and also the above-mentioned physical
properties of polymer (A) in the present invention, is as follows.
The Mw can be adjusted, for example, by changing temperature,
monomer concentration (solvent concentration), quantity of catalyst
and quantity of chain transfer agent, at polymerization. The SP
value can be adjusted by selecting adequate kind of monomers and
choosing their molar ratio by calculating SP value of the intended
polymer using SP value of each constituting unit (such SP value is
calculated by the Fedors method). For example, SP value of polymer
can be adjusted by selecting monomer(s) having appropriate length
of alkyl group(s). The longer such alkyl length is, the smaller SP
of polymer becomes. Adversely, the shorter such alkyl length is,
the larger SP of polymer becomes. The Tc can be adjusted by
selecting appropriate length of a methylene-chain existing in
backbone and/or side-chain of polymer. For example, Tc becomes
higher if the monomer having longer methylene-chain at an alkyl
group in its side chain, is employed. Adversely, Tc becomes lower
if the monomer having shorter methylene-chain at an alkyl group in
its side chain, is employed. The F can be adjusted by selecting
kinds of monomer and their molar ratio. For example, the F becomes
smaller when employed more quantity of monomer(s) having less
number of atoms at the sixth or the seventh position.
[0108] The polymer has HLB value of preferably 0.5-6, more
preferably 1-5.5, particularly 1.5-5. If HLB is in this range, in
particular, anti-emulsification is preferable. The above HLB value
is calculated using HLB definition of Oda method based on a general
concept of organic and inorganic nature of organic compound ("New
Introduction to Surface Active Agents" T. FUJIMOTO, SANYO CHEMICAL
INDUSTRIES, LTD.P 197-201).
COPOLYMER (A11)
[0109] Another component of the present invention is the copolymer
(A11). The copolymer (A11) contains generally 5-90%, preferably
10-80%, more preferably 10-70%, particularly 10-60%, more
particularly 10-45% of units of (a11). The copolymer (A11) contains
generally 5-95%, preferably 20-90%, more preferably 30-90%,
particularly 40-90%, more particularly 55-90% of units of
alkyl(meth)acrylates that are other than (a11). The expression
"alkyl (meth)acrylates that are other than (a11)" means such
acrylates are without the definition of the monomer group (a11);
and similar expression is used hereinafter.
[0110] The monomers that are other than (a11), include the
above-mentioned monomer (a2), (a3), (a12), (a4) and (a5). The
copolymer (A11) includes generally 10-60%, preferably 20-50%,
particularly 25-45% of units of (a2). The copolymer (A11) includes
generally 0-85%, preferably 10-70%, particularly 10-60% of total
units of (a3), (a12), (a4) and (a5).
[0111] In one most preferable embodiment, the copolymer (A11) is
prepared by polymerizing 10-40% 2-decyl-tetradecyl methacrylate,
20-45% methyl methacrylate and 10-60% alkyl (meth) acrylates that
are within the groups of (a3) and (a4) and also have C.sub.10-18
straight-chain alkyl group.
[0112] If VII is required the property of a detergent as well as
VII, in one preferable embodiment, the polymer (A11) also include
the 0.1-10% (d) based on the total weight of monomers consisting
(A11), especially, one or several monomer(s) selecting from the
group consisting of dimethylaminoethyl (meth)acrylate,
diethylaminoethyl (meth)acrylate and morpholinoethyl
(meth)acrylate; the said three compounds are within the monomer
(d).
[0113] The preferable Mw, SP, Tc and the F of the copolymer (A11),
are the same range of ones of the polymer (A) as described
above.
[0114] As the VII of the present invention, (A11) can be used by
itself or (A11) can be used together with (A) that is other than
(A11). A ratio of such combined usage is preferably (A11)/(A) other
than (A11)=100/0-20/80, more preferably 100/0-70/30.
PREPARATION OF THE POLYMERS (A) AND (A11)
[0115] The polymers (A) and (A11) of the present invention can be
prepared by conventional methods well known to those of skill in
the art. For instance, the polymer is prepared by radical
polymerization of above-mentioned monomer(s) with solvent and
polymerization catalyst.
[0116] The solvent includes, for example, aromatic compounds such
as aromatic solvents having 7-15 carbon atoms (e.g., toluene,
xylene, ethylbenzene, alkylbenzene having 9-10 carbon atoms,
mixtures of trimethyl benzene, ethyltoluene, etc.); ketone solvents
(e.g., butanone, etc.); and mineral oils such as solvent refining
oils, paraffin oils, isoparaffin containing and/or hydrogenolysis
high viscosity index oils, hydrocarbon synthetic lubricants (e.g.,
poly alpha-olefinic synthetic lubricant), ester synthetic
lubricants, naphthene oils, and the like.
[0117] The polymerization catalyst includes, for example, azo
catalyst (e.g., 2,2'-azo-bis-isobutyronitrile,
2,2'-azo-bis-(2-methyl) butyronitrile, ADVN, dimethyl
2,2-azo-bis-isobutylate, etc.); and peroxide catalyst (e.g.,
t-butyl-peroxypivalate, t-hexyl-peroxypivalate,
t-butyl-peroxyneoheptanoate, t-butyl-peroxyneodecanoate,
t-butyl-peroxy2-ethylhexanoate, t-butyl-peroxyisobutylate,
t-amyl-peroxy2-ethylhexanoate,
1,1,3,3-tetramethylbutyl-peroxy2-ethylhexa- noate,
dibutyl-peroxytrimethyl adipate, benzoyl peroxide, cumyl peroxide,
lauryl peroxide, etc.).
[0118] Further, if necessary, chain transfer agent (e.g., alkyl
mercaptan having 2-20 carbon atoms, mercaptoacetic acid,
mercaptopropionic acid, triethylene glycol dimercaptan, etc.) can
be used in the synthesis.
[0119] The concentration of monomer(s) is preferably 40-95%, more
preferably 60-90% based on weight of all chemicals including
solvent in synthesis. The concentration of polymerization catalyst
is preferably 0.1-5%, more preferably 0.15-0.5% based on weight of
all monomer(s) in synthesis. The concentration of chain transfer
agent is preferably 0-5%, more preferably 0-3% based on weight of
all monomer(s) in synthesis.
[0120] The polymerization temperature is preferably 50-140.degree.
C., more preferably 70-120.degree. C.
[0121] In addition, polymerization reaction can be bulk
polymerization, emulsion polymerization or suspension
polymerization in addition to the above-mentioned solution
polymerization. Copolymerization can be by random copolymerization
or alternating copolymerizaton, preferably random copolymerization.
And also graft copolymerization or block copolymerization can be
employed.
THE VISCOSITY INDEX IMPROVER
[0122] The viscosity index improver (VII) of the present invention,
can be a solvent-free polymer (A1) or (A11), or can be a solution
of the polymer (A) or (A11). The solution of the polymer prepared
by solution polymerization, can be used as VII concentrates. In
other embodiment, a diluent can also be added to a substantially
solvent-free polymer, usually by dissolving the substantially
solvent-free polymer in an appropriate diluent, making VII
concentrates. The solution of the polymer, namely VII concentrate
is preferable. Because, the polymer dissolves easily in base oil,
if the polymer is diluted with diluent beforehand.
[0123] Examples of the diluents (hereinafter referred as (C)) are
C.sub.6-18 aliphatic hydrocarbons (e.g., hexane, heptane,
cyclohexane, octane, decalin, kerosene, etc.), the above-mentioned
aromatic compound andm ineral oils. A preferable diluent among
these examples is mineral oil. The VII concentrates of the present
invention, contains VII of preferably 10-90%, more preferably
30-80% and also contains diluent of preferably 10-90%, more
preferably 20-70%.
THE LUBE OIL COMPOSITION
[0124] Base oil in which VII of the present invention is added, is
not particularly limited. Preferably, such base oil has a kinematic
viscosity at 100.degree. C. of, typically 1-15 mm.sup.2/s, more
often 2-5 mm.sup.2/s. Preferably, such base oil has a VI value of
typically at least 80, more often at least 100. The finished lube
oil composition that is added the VII of the present invention into
base oil, is improved to have larger VI and shows improved fuel
efficiency.
[0125] In addition, such base oil has a cloud point (defined in JIS
K2269) of, preferably equal to or less than -5.degree. C., more
preferably equal to or less than -10.degree. C., particularly equal
to or less than -15.degree. C. If a cloud point of base oil is the
range mentioned above, quantities of deposition of wax is so small
at low temperature, that viscosity behavior at low temperature is
excellent. Such base oil includes, for example, mineral oils that
is mentioned above. Preferable mineral oils are high viscosity
index oils contained isoparaffin and/or manufactured by
hydrocracking,. Normally, the lube oil composition of present
invention include 0.5-30% of the polymer (A) or (A11).
[0126] In one embodiment, the finished lube oil composition is
intended as engine oil, preferably, 0.5-15% of the (A) or (A11),
are added to base oil having a 3-10 mm.sup.2/s kinematic viscosity
at 100.degree. C. In another embodiment, the finished lube oil
composition is intended as gear oil, preferably, 3-30% of the (A)
or (A11), are added to base oil having 3-10 mm.sup.2/s a kinematic
viscosity at 100.degree. C. In yet another embodiment, the finished
lube oil composition is intended as automatic-transmission fluid
(e.g., ATF, CTVF etc.), preferably, 2-25% of the (A) or (A11), is
added to base oil having 2-6 mm.sup.2/s a kinematic viscosity at
100.degree. C. In further embodiment, the finished lube oil
composition is intended as traction oil, preferably, 0.5-15% of the
(A) or (A11), are added to base oil having 1-5 mm.sup.2/s a
kinematic viscosity at 100.degree. C. In yet further embodiment,
the finished lube oil composition is intended as hydraulic oil,
preferably, 0.5-25% of the (A) or (A11), is added to base oil
having 1-10 mm.sup.2/s a kinematic viscosity at 100.degree. C.
[0127] The lube oil compositions of this invention containing VII
of (A) or (A11), may further contain, optionally, another kind of
additives. The examples of such another kind of additives are
copolymers of alkyl (meth)acrylate (other than such copolymer
classified (A)); such copolymers are hereinafter referred to as (B)
Examples of (B) are copolymers comprise units derived from (a), and
such copolymers have at least one of SP, Tc, F or Mw of without the
aforesaid range that preferable (A) are encompassed. Preferable
monomers compose (B), are the monomers within a group selecting
from the group consisting of (a2), (a3), (a4), (a5), and (a6), that
are included the above-mentioned monomer group (a), and are the
monomers from any group of (a2) to (a6). In one preferred
embodiment, the copolymer (herein after refereed to as (B1)) is
composed of (a2) and (a3), or composed of (a2) and (a4), or
composed of (a2), (a3) and (a4). In another preferred embodiment,
the copolymer (hereinafter refereed to as (B2)) is composed of two
or more kind of monomers selecting from (a3) and/or (a4). In the
(B1), the monomer ratio of (a2)/(a3)+(a4) is preferably
(0-40)/(60-100), more preferably (5-35)/(65-95). In one particular
embodiment of (B2), at least one kind of monomer composing (B2) has
one having 12 to 18 carbon atoms, and average carbon atoms of all
the monomers (B2) is 12 to 16, and the content of a branched-alkyl
group is 0-30 mole %.
[0128] In one particular embodiment, the copolymer (B1) comprises
(a2), (a3) and (a4), for example, copolymers of methyl
methacrylate/dodecyl methacrylate/tetradecyl methacrylate/hexadecyl
methacrylate (0-20%/20-45%/20-45%/0-20%). In one particular
embodiment, the copolymer (B2) comprises (a3) and (a4), for
example,
[0129] copolymers of dodecyl methacrylate/hexadecyl methacrylate
(10-50%/50-90%), that have an average carbon atoms of 12.3-13.8,
and have branched-alkyl group contents of 0 mol %;
[0130] copolymers comprises two kinds of monomers of (a3), for
example, copolymers of dodecyl methacrylate/tetradecyl methacrylate
(90-70%/10-30%), that have an average carbon atoms of 12.2-12.6,and
that have branched-alkyl group contents of 0 mol %; and
[0131] copolymers of dodecyl acrylate/dodecyl methacrylate
(10-40%/90-60%), that have an average carbon atoms of 12, and have
branched-alkyl group contents of 0 mol %.
[0132] As the additional VII, (B) may use alone, or may use more
than two kinds together. Mw of (B) is preferably 5,000-1,000,000,
more preferably 10,000-250,000.
[0133] The lube oil composition of the present invention may
contain further alkyl (meth)acrylate ester copolymers (B 11) other
than the copolymer (A11).
[0134] In one embodiment, (B11) include alkyl (meth)acrylate ester
copolymers that comprise (a11) of less than 5% or of greater than
90%. In another embodiment, (B11) include copolymers within the
definition of (B) and comprise the units of the monomers (a11) of
less than 5% or of greater than 90%. Preferable monomers compose
(B11), are the same monomers as the ones that (B) are composed of,
which are described above. Preferable (B11) has the same Mw range
as the (B) has, which are also described above.
[0135] (B11) can be prepared by the same method as one for (A)
preparation, mentioned above.
[0136] The (B) or (B11) can be mixed to (A) or (A11) in advance,
then add to a base oil. And slso, (B) or (B11), and (A) or (A11)
can be separately added to a base oil.
[0137] The total amount of the (B) and (A), or (B) and (A11), to be
added to a base oil is the same preferable range as the one of (A)
or (A11), above-mentioned.
[0138] The lube oil composition of this invention may further
contain one or more additives usually used in a lube oil. Such
additives include, for example, detergents, also referred to as an
overbased or neutral metal salt (e.g., overbased alkali or alkaline
earth metal salts of a sulfonate, phenate, naphthate, salicylate,
carbonate, or mixtures thereof, etc.), dispersants (e.g.,
succinimide type; bis type, mono type and borate type, Mannich
dispersants, etc.), antioxidants (e.g., hindered phenolic
antioxidants, secondary aromatic amine antioxidants, etc.),
friction modifier (e.g., long chain fatty acids; oleic acid, long
chain fatty acid esters; oleate, long chain amines; oleylamine,
long chain amide; oleylamide, etc.), antiwear agents (e.g.,
molybdenum dithio phosphate, molybdenum dithio carbamate, zinc
dialkyl dithiophosphate, etc.), extreme-pressure agents (e.g.,
sulfur phosphide compounds, sulfur compounds, phosphide compounds,
chloro compounds, etc.), antifoam agents (e.g., silicone oil,
metallic soap, fatty acid ester, phosphate compounds, etc.),
demulsifying agents (e.g., tetra ammonium salt compounds, sulfated
oil., phosphate compounds, etc.) and corrosion inhibitors (e.g.,
nitrogen compound; benz-triazole, 1,3,4-thiodiazoryl-2,5-bis
dialkyl dithiocarbamate, etc.).
[0139] These additives can be used in such amounts: 0-20%,
preferably 0.1-10% of the detergent; 0-20%, preferably2.0-10% of
the dispersant; 0-5%, preferably 0.1-3% of the antioxidants; 0-5%,
preferably 0.1-1% of the friction modifier; 0-5%, preferably 0.1-3%
of the antiwear agent; 0-20%, preferably 1.0-10% of the
extreme-pressure agent; 2-1000 ppm, preferably 10-700 ppm of the
antifoam agent; 0-3%, preferably 0-1% of the demulsifying agent;
and 0-3%, preferably 0-2% of the corrosion inhibitor.
[0140] Lube oil compositions of this invention are useful as engine
oils (such as an engine for means of transportation and engine for
machine tools), gear oil, transmission lube oil (particularly, ATF
and fluid for CTV), traction oil, shock-absorber oil, power
steering oil, and the like.
2-DECYL-TETRADECYL (METH)ACRYLATE, AND ITS POLYMER
[0141] Another component of the present invention is a monomer of
2-decyl-tetradecyl (meth)acrylate (hereinafter referred as DTDA), a
homopolymer of the DTDA and the copolymers comprising of the units
of DTDA.
[0142] The 2-decyl-tetradecyl (meth)acrylate is presented by the
general formula (4): 4
[0143] In the formula (4), R.sup.4 is methyl group (i.e.,
2-decyl-tetradecyl methacrylate) or R.sup.4 is hydrogen atom (i.e.,
2-decyl-tetradecyl acrylate).
[0144] A DTDA can be prepared by an esterification using
2-decyl-tetradecyl alcohol and (meth) acrylic acid, or can be
prepared by a transesterification using 2-decyl-tetradecyl alcohol
and (meth)acrylic acid derivatives. The 2-decyl-tetradecyl alcohol
is commercially available, for example, under the trade name of
"ISOFOL24" from CONDEA Chemie GmbH. The (meth)acrylic acid
derivatives include an (meth)acrylic acid halide (e.g.,
(meth)acrylic acid chloride, (meth)acrylic acid bromide, etc.), an
(meth)acrylate acid anhydride, and a short-chain alkyl (carbon
number 1-4: such as methyl, ethyl, etc.) (meth)acrylate, preferably
methyl (meth)acrylate. The esterification or transesterification is
carried out with or without solvent.
[0145] For example, the esterification or transesterification with
or without solvent is carried out as follows: Alcohol,
polymerization inhibitor, (solvent), a catalyst and (meth)acrylic
acid or its derivative described above, are charged in a reactor
and are reacted under normal or reduced pressure at 70-140.degree.
C., preferably 100-120.degree. C. The solvent is, for example, the
above-mentioned aromatic solvent, mineral oil, and the like.
Preferred solvents are benzene, toluene, xylene and the like,
because using such solvent, it is easy to separate and remove
by-products of water or lower alcohol. The polymerization inhibitor
is, for example, a phenol compound (e.g., hydroquinone,
hydroquinone monomethyl ether, p-benzoquinone, t-butyl cresol,
catechol, etc.), phenothiazine, oxygen and air. These are usedalone
or together. The catalyst is for example, an acid catalyst (e.g.,
sulfuric acid, hydrochloric acid, p-toluenesulfonic acid,
methanesulfonic acid, benzenesulfonic acid, xylene sulfonic acid,
etc.,) or abase catalyst (e.g., sodium hydroxide, potassium
hydroxide, sodium alcoholate, etc.). The reaction liquid that the
reaction was completed, is washed with water or aqueous alkali
solution, if necessary, and refined removing the catalyst, the
polymerization inhibitor or unreacted (meth)acrylic acid.
[0146] The homopolymer of the DTDA is prepared by the same process
as the process of the (a11) homopolymer, mentioned above. The
copolymer having the DTDA is prepared by the same process as the
process of the copolymer (A) or (A11), mentioned above.
EXAMPLE
[0147] Having generally described the invention, a more complete
understanding can be obtained with reference to certain specific
examples, which are included for purposes of illustration only and
are not intended to limit the scope of the present invention.
[0148] In the following examples, parts represents parts by
weight.
DTDA SYNTHESIS
[0149] Into a 2 litter reaction vessel equipped with a thermometer,
a stirrer, a dehydrator, a condenser, an air inlet tube, a nitrogen
gas inlet tube, and a dropping funnel, 1000 parts of an "ISOFOL
24," 1.1 parts of a hydroquinone and 4 parts of a concentrated
sulfuric acid were charged. 315.8 parts of methacrylic acid were
added dropwise into the reaction mixture, over two hours, at the
temperature 90.degree. C., with bubbling air at gas flow for 25
ml/min. Simultaneously, the vessel was warming, so that the
reaction mixture reached 120.degree. C. when the addition was
completed. The mixture was maintained at 120.degree. C. for two
hours to complete the estrification. Reducing the pressure to 4 kPa
from atmospheric pressures, at 125.degree. C., the unreacted
methacrylic acid was removed. Then, 32 parts of 10% sodium
hydroxide water solutions were added with stirring under less than
30.degree. C., to neutralize the solution. Then, the upper layer
was separated from the lower layer. In the upper layer including
crude 2-decyl-tetradecyl methacrylate, five parts of an adsorbent
"KYOWAAD-500SH" (Kyowa chemical industry Co., Ltd.) were added and
stirred for 60 min., at 60.degree. C., then containing water was
removed by evaporation. The product was separated from the solid
impurities by filtration. The 1,100 parts of 2-decyl tetradecyl
methacrylate was obtained. The solidifying point was -33.degree. C.
to -35.degree. C.
[0150] FIG. 1 shows a .sup.1H--NMR spectrogram of the product, FIG.
2 shows a .sup.13C--NMR spectrogram of the product, and FIG. 3
shows an IR absorption spectrogram of the product.
[0151] Referring to the FIG. 1, the spectrogram shows following
resonance peaks, shapes, coupling constants and the number of
hydrogen atoms: 1H--NMR (CDCl.sub.3,300 MHz): .delta. 6.08 (s, 1H),
5.52 (s,1H), 4.04(d, J=6 Hz, 2H), 1.93 (s, 3H), 1.6-1.7 (m, 1H),
1.1-1.4 (m, 40H), 0.87 (t, J=6 Hz, 6H). Referring the FIG. 2, the
spectrogram shows following resonance peaks: .sup.13C--NMR
(CDCl.sub.3,300 MHz): .delta. 167.6, 136.7, 125.0, 67.3, 37.2,
31.8, 31.3, 29 .8, 29.6, 29.5, 29.5, 29.3, 26.6, 22.5, 18.1, 13 .9.
Referring the FIG. 3, the spectrogram shows following absorption
frequency: IR (NaCl): 2924, 2855, 1720, 1639, 1466, 1319, 1296,
1165, 1013,937, 814, 721cm.sup.-1
[0152] The 2-decyl tetradecyl acrylate is prepared by a similar
process.
THE METHODS
[0153] [The method of measuring a Mw for the copolymers]
[0154] Molecular weight distribution was measured by gel-permeation
chromatography (GPC). The conditions for the measurement were as
follows:
[0155] Apparatus: HLC-802A, (Toyo Soda Co., Ltd.)
[0156] Column: TSKgel-GMH6, (Toyo Soda Co., Ltd.) connecting two
columns in series
[0157] Column Temperature: 40.degree. C.
[0158] Specimen (Sample solution): 0.5 weight % tetrahydrofuran
(THF) solution
[0159] Injection amount of specimen: 200 micro L
[0160] Detector: a refractive index detector
[0161] In addition, the calibration curve of molecular weight was
prepared to use polystylene as a reference standard.
[0162] [The method of measuring a low-temperature viscosity]
[0163] The low-temperature viscosity was measured following
JPI-5S-26-85 at -40.degree. C.
[0164] [The method of measuring a VI]
[0165] The viscosity index was measured following JIS-K-2283.
[0166] [The method of measuring a shear stability]
[0167] The shear stability was measured according to JASO M347-95,
the period of test time was 12 hours. In addition, the liquid level
is adjusted every three hours.
HOMOPOLYMER
[0168] The monomers listed in the Table 1 were polymerized
following the above-mentioned method of the homopolymerization, and
obtained the homopolymers. The crystallizing initiation temperature
of the homoplymers is shown in table 1.
1TABLE 1 Tc (.degree. C.) of Monomer homopolymer a1-1
2-decyl-tetradecyl methacrylate -30 a1-2 2-dodecyl-hexadecyl
methacrylate -14 a1-3 2-decyl-tetradecyloxyethyl methacrylate -25
a3-1 2-ethylhexyl methacrylate <-40 (*1) a5-1 n-dococyl
methacrylate 45 (*1) less than -40.degree. C.
[0169] Except for the homopolymer consisiting the units of (a5-1),
the other homopolymers have Tc of less than 5.degree. C.
COPOLYMER PREPARATION
Example 1-9, Example 51, and Comparative Example 1-3
[0170] Into a reaction vessel equipped with a stirrer , a heating
and cooling device, a thermometer, a dropping funnel and a nitrogen
gas inlet tube, 25 parts of a toluene was charged. After the
atmosphere in the vessel is replaced with nitrogen gas, the
solution consisting of the listed amount (parts) of the listed
monomer, DM and ADVN, in the table 2, was added dropwise from the
dropping funnel. This addition was made over a period of 4 hours,
at 85.degree. C., in the absence of air. Further the reaction
mixture was stirred at 85.degree. C. for 2 hours, so that the
polymerization proceeds well. Thereafter, toluene was evaporated
under reduced pressure at 130.degree. C., for 3 hours. The
copolymers, (A-1) to (A-9), (B-1) and (X-1) to (X-3), were
obtained. The physical property of the copolymers are shown in
table 3.
2 TABLE 2 Copoly- mer Monomer D AD name a1-1 a1-2 a1-3 a3-1 a5-1
a2-1 a4-1 a4-2 a3-2 d-1 d-2 M VN Example 1 A-1 32 36 30 2 0.9 0.5 2
A-2 20 36 12 32 0.9 0.5 3 A-3 20 32 10 38 0.9 0.5 4 A-4 30 38 32
0.9 0.5 5 A-5 20 38 12 30 0.9 0.5 6 A-6 20 30 50 0.9 0.5 7 A-7 30
10 35 23 2 0.9 0.5 8 A-8 30 35 35 0.3 0.5 9 A-9 20 10 70 0.9 0.5 51
B-1 20 80 0.3 0.4 C. Example 1 X-1 48 50 2 0.9 0.5 2 X-2 55 45 0.9
0.5 3 X-3 40 30 30 0.9 0.5 a2-1: methyl methacryate a4-1:
n-hexadecyl methacrylate a4-2: n-octadecyl methacrylate a3-2:
n-dodecyl methacrylate d-1: N,N-dimethyl aminoethyl methacrylate
d-2: N,N-diethyl amino ethyl methacrylate
[0171]
3 TABLE 3 Copoly- mer Mw Tc name (.times. 10.sup.4) SP (.degree.
C.) F HLB Example 1 A-1 2 9.2 <-40.degree. C.(*1) 7.2 3.1 2 A-2
3 9.2 <-40.degree. C. 6.6 3.2 3 A-3 3 9.2 <-40.degree. C. 5.6
3.2 4 A-4 3 9.2 <-40.degree. C. 6.6 3.1 5 A-5 3 9.3
<-40.degree. C. 6.2 3.3 6 A-6 3 9.2 <-40.degree. C. 8.0 3.0 7
A-7 2 9.2 <-40.degree. C. 7.9 3.1 8 A-8 6 9.2 <-40.degree. C.
7.5 3.1 9 A-9 3 9.2 <-40.degree. C. 9.1 2.7 51 B-1 6 9.0 -17
15.0 1.9 C. Example 1 X-1 2 9.0 <-40.degree. C. 23.0 2.5 2 X-2 3
9.5 <-40.degree. C. 3.7 4.5 3 X-3 3 9.2 19 6.0 2.7 (*1) less
than 40.degree. C.
[0172] The copolymer (B-1) of the above Example 51 was an another
copolymer that adding together with the VII of the present
invention ((A-1) to (a-9)) into base oil.
VII CONCENTRATES
[0173] 65 parts of each of the copolymers (A-1) to (A-9) and (X -1)
to (X-3) was dissolved in 35 parts of the mineral oil (solvent
refining oil: kinematic viscosity at 100.degree. C. 2.4
mm.sup.2/s). The VII concentrates were obtained.
[0174] 65 parts of the copolymer (B-1) was dissolved in 35 parts of
the same mineral oil as the above. The copolymer concentrate was
obtained.
LUBE OIL COMPOSITION
Example 10-18, Comparative Example 4-6
[0175] Into a container made by the stainless steel equipped with a
stirrer, 0.5 parts concentrate of the (B-1) were charged. Each of
the concentrates of (A-1) to (A-9) and (X-1) to (X-3) and base oil
(kinematic viscosity at 100.degree. C., 3.0 mm.sup.2/s, a viscosity
index, 117) was added respectively, so as to becoming the final
lube oil composition has a kinematic viscosity at 100.degree. C. of
6.0.+-.0.1 mm.sup.2/s, and also becoming the final lube oil
composition of 100 parts. The lube oil compositions (10-18) of the
present invention and the composition of the comparative example
(4-6) were obtained. The VI, low temperature viscosity at
-40.degree. C. and shear stability of the resultant compositions
are given in table 4.
4 TABLE 4 Amount of Low Temp. Shear VII concentrate Copolymer
Viscosity Stability (part) name VI (mPa .multidot. s) (%) Example
10 17 A-1 229 9900 10 11 17 A-2 232 10000 10 12 17 A-3 231 10000 10
13 17 A-4 232 9500 10 14 17 A-5 232 9800 10 15 17 A-6 229 8800 10
16 17 A-7 228 9900 10 17 13 A-8 263 5200 25 18 17 A-9 218 7000 11
C.Example 4 17 X-1 208 11000 12 5 Not dissolved X-2 -- -- -- 6 17
X-3 231 >400,000 10 (*1) (*1) more than 400,000 mPa .multidot.
s
[0176] The compositions 10 to 18 are inventive examples and the
compositions 4-6 are comparative examples. The compositions 10 to
18 have higher VI and lower low-temperature viscosity. The
composition 4 shows lower VI. The X-2 in the composition 5 did not
dissolve into the base oil. The composition 6 shows higher VI,
however extremely high low-temperature viscosity.
LUBE OIL COMPOSITION
Example 19-27, Comparative Example 7-9
[0177] The procedure same as the Example 10 was repeated with the
exception that the final lube oil composition has a kinematic
viscosity at 100.degree. C. of 5.0.+-.0.1 mm.sup.2/s. The lube oil
compositions (19-27) of the present invention and the composition
of the comparative example (7-9) were obtained. The VI,
low-temperature viscosity at -40.degree. C. and shear stability of
the resultant composition are given in table 5.
5 TABLE 5 Amount of VII Low Templ Shear concentrate Copolymer
Viscosity Stability (part) name VI (mPa .multidot. s) (%) Example
19 13 A-1 216 5700 9 20 13 A-2 218 6000 9 21 13 A-3 217 6000 9 22
13 A-4 218 5500 9 23 13 A-5 218 5600 9 24 13 A-6 216 5200 9 25 13
A-7 215 5700 9 26 10 A-8 241 4000 20 27 13 A-9 204 4800 10
C.Example 7 13 X-1 195 6600 12 8 Not X-2 -- -- -- dissolved 9 13
X-3 217 >400,000 9 (*1) (*1) more than 400,000 mPa .multidot.
s
[0178] Similar result as the series of the experiments of table 4
was obtained.
* * * * *