Note: Descriptions are shown in the official language in which they were submitted.
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i
DESCRIPTION
,
Title of Invention
,
VISCOSITY INDEX IMPROVER, METHOD FOR PRODUCING SAME, AND
OIL COMPOSITION
Technical Field
[0001]
The present invention relates to a viscosity index improver including a
hydrogenated product of a copolymer containing a constitutional unit derived
from farnesene, a process for producing the viscosity index improver, and an
oil
composition containing the viscosity index improver and a base oil.
Background Art
[0002]
Hydrogenated products of block copolymers constituted of a polymer
block containing a constitutional unit derived from an aromatic vinyl compound
and a polymer block containing a constitutional unit derived from a conjugated
diene exhibit properties similar to those of vulcanized rubbers without
further
subjecting the hydrogenated products to vulcanization, i.e., are excellent in
damping property, flexibility, rubber elasticity and weather resistance, and
therefore have been extensively used in the applications such as sundries,
parts
for automobiles, various industrial parts, etc.
The hydrogenated products of block copolymers are produced, for
example, by subjecting a block copolymer obtained by sequentially
polymerizing an aromatic vinyl compound and a conjugated diene such as
isoprene and butadiene to hydrogenation (for example, refer to PTL1 and
PTL2).
In addition, PTL3 describes that the hydrogenated products of block
copolymers constituted of a polymer block containing a constitutional unit
derived from an aromatic vinyl compound and a polymer block containing a
constitutional unit derived from a conjugated diene are used as an viscosity
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index improver for lubricating oils.
Meanwhile, PTL4 and PTL5 describe a polymer of 6-farnesene, but fail
to make a sufficient study on practical properties thereof.
Citation List
Patent Literature
[0003]
PTL1: JP 2777239B
PTL2: JP 2010-090267A
PTL3: JP 2009-532513A
PTL4: JP 2012-502135A
PTL5: JP 2012-502136A
Summary of Invention
[0004]
The viscosity index improver described in PTL3 is excellent in an effect
of improving a viscosity index and a high-temperature high-shear viscosity of
lubricating oils. However, it has been still demanded to develop different
kinds of viscosity index improvers that are more excellent in the above
effect.
The present invention relates to a viscosity index improver that
improves the viscosity index and the high-temperature
high-shear viscosity of oils, a process for producing the viscosity index
improver,
and an oil composition that is enhanced in viscosity index and
high-temperature =high-shear viscosity
= [0005]
The present invention relates to the following aspects [1] to [3].
[1] A viscosity index improver consisting of a hydrogenated product of a
copolymer containing a constitutional unit (a) derived from an aromatic vinyl
compound and a constitutional unit (b) derived from a conjugated diene,
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the content of a constitutional unit (bp derived from farnesene in the whole
amount of the constitutional unit (b) derived from the conjugated diene being
from 1 to 100% by mass, and the content of a constitutional unit (b2) derived
from
a conjugated diene other than farnesene in the whole amount of the
constitutional unit (b) derived from the conjugated diene being from 0 to 99%
by mass, and
50 mol% or more of carbon-carbon double bonds in the constitutional
unit (b) derived from the conjugated diene being hydrogenated.
[2] An oil composition including a base oil and the viscosity index improver
according to the above aspect [11.
[3] A process for producing the viscosity index improver according to the
above
aspect [11, including:
a polymerization step of obtaining the copolymer containing the
constitutional unit (a) derived from the aromatic' vinyl compound and the
constitutional unit (b) derived from the conjugated diene by anionic
polymerization; and
a hydrogenation step of hydrogenating 50 mol% or more of
carbon-carbon double bonds in the constitutional unit (b) derived from the
conjugated diene.
[0006]
According to the present invention, it is possible to provide a viscosity
index improver that improves the viscosity index and the
high-temperature high-shear viscosity of oils, a process for producing the
viscosity index improver, and an oil composition that is enhanced in viscosity
index and high-temperature high-shear viscosity.
Description of Embodiments
[0007]
[Viscosity Index Improver]
The viscosity index improver of the present invention consists of a
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hydrogenated product of a copolymer containing a constitutional unit (a)
,
derived from an aromatic vinyl compound and a constitutional unit (b) derived
from a conjugated diene (the copolymer may also be hereinafter referred to
merely as a "copolymer", and the hydrogenated product of the copolymer may
also be hereinafter referred to merely as a "hydrogenated copolymer"), in
which
a content of a constitutional unit (b1) derived from farnesene in a whole
amount of the constitutional unit (b) derived from the conjugated diene is
from
1 to 100% by mass, and a content of a constitutional unit (b2) derived from a
conjugated diene other than farnesene in a whole amount of the constitutional
unit (b) derived from the conjugated diene is from 0 to 99% by mass, and 50
mol% or more of carbon-carbon double bonds in the constitutional unit (b)
derived from the conjugated diene are hydrogenated.
[0008]
The hydrogenated copolymer constituting the viscosity index improver
of the present invention may be in the form of either a hydrogenated product
of
a block copolymer or a hydrogenated product of a random copolymer.
More specifically, the viscosity index improver of the present invention
may also be constituted of a hydrogenated product of a block copolymer
including a polymer block (A) containing the constitutional unit (a) derived
from the aromatic vinyl compound as a main component and a polymer block
(B) containing the constitutional unit (b) derived from the conjugated diene
as a
main component (hereinafter also referred to merely as a "hydrogenated block
copolymer").
In addition, the viscosity index improver of the present invention may
also be constituted of a hydrogenated product of a random copolymer obtained
by random polymerization of the constitutional unit (a) derived from the
aromatic vinyl compound, the constitutional unit (b 1) derived from farnesene
and the constitutional unit (b2) derived from the conjugated diene other than
farnesene (hereinafter also referred to merely as a "hydrogenated random
copolymer").
[0009]
Constitutional Unit (a) Derived From Aromatic Vinyl Compound>
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The aforementioned copolymer contains the constitutional unit (a)
derived from the aromatic vinyl compound. Examples of the aromatic vinyl
compound include styrene, a-methylstyrene, 2-methylstyrene, 3-methylstyrene,
4-methylstyrene, 4-propylstyrene, 4-t-butylstyrene, 4-cyclohexylstyrene,
5 4-dodecylstyrene, 2,4-dimethylstyrene,
2,4-diisopropylstyrene,
2,4,6-trimethylstyrene, 2-ethyl-4-benzylstyrene,
4-(phenylbutypstyrene,
1-vinylnaphthalene, 2-vinylnaphthalene,
vinylanthracene,
N,N-diethy1-4-aminoethylstyrene, vinylpyridine,
4-methoxystyrene,
monochlorostyrene, dichlorostyrene and divinylbenzene. These aromatic vinyl
compounds may be used alone or in combination of any two or more thereof.
Of these aromatic vinyl compounds, from the viewpoint of improving a viscosity
index and a high-temperature high-shear viscosity of oils, preferred are
styrene,
a-methylstyrene and 4-methylstyrene, and more preferred is styrene.
Meanwhile, in the present invention, compounds containing both of an
aromatic group and a conjugated diene bond in a molecule thereof should be
excluded from the conjugated diene as the component from which the
constitutional unit (b) is derived, and should be included in the aromatic
vinyl
compound as the component from which the constitutional unit (a) is derived.
However, the content of the compounds containing both of an aromatic group
and a conjugated diene bond in a molecule thereof in the constitutional unit
(a)
is preferably not more than 10% by mass, more preferably not more than 5% by
mass, and still more preferably not more than 1% by mass.
loom]
(Constitutional Unit (b) Derived From Conjugated Diene>
The aforementioned copolymer includes the constitutional unit (b)
derived from the conjugated diene. The copolymer contains a constitutional
unit (b 1) derived from farnesene as the constitutional unit (b), and may
further
contain a constitutional unit (b2) derived from a conjugated diene other than
farnesene as the constitutional unit (b).
The content of the constitutional unit (b1) derived from farnesene in a
whole amount of the constitutional unit (b) derived from the conjugated diene
is
from 1 to 100% by mass, preferably from 40 to 100% by mass, more preferably
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from 50 to 100% by mass, still more preferably from 55 to 100% by mass, even
still more preferably from 60 to 100% by mass, further even still more
preferably from 90 to 100% by mass, and further even still more preferably
from 95 to 100% by mass.
Also, the content of the constitutional unit (b2) derived from the
conjugated diene other than farnesene in a whole amount of the constitutional
unit (b) derived from the conjugated diene is from 0 to 99% by mass,
preferably
from 0 to 60% by mass, more preferably from 0 to 50% by mass, still more
preferably from 0 to 10% by mass, and even still more preferably from 0 to 5%
by mass.
The farnesene may be industrially produced from sugars as a raw
material which are extracted from plants such as canes by using
microorganisms. Thus, the viscosity index improver of the present invention
can be produced with a less burden on environments by using the farnesene as
a raw material.
[0011]
(Constitutional Unit (b1) Derived From Farnesene)
The farnesene as the component from which the constitutional unit (bl)
is derived may be either a-farnesene or 13-farnesene represented by the
following formula (I), or a-farnesene and P-farnesene may be used in
combination with each other to form the constitutional unit (bl).
The content of a constitutional unit derived from 13-farnesene in the
constitutional unit (b1) is preferably not less than 60% by mass, more
preferably not less than 80% by mass, still more preferably not less than 90%
by mass, even still more preferably not less than 99% by mass, and further
even still more preferably 100% by mass, from the viewpoints of facilitating
production of the copolymer and improving a viscosity index and a
high-temperature high-shear viscosity of oils.
[0012]
( I )
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[0013]
(Constitutional Unit (b2) Derived From Conjugated Diene Other Than
Farnesene)
The aforementioned copolymer may contain a constitutional unit (b2)
derived from a conjugated diene other than farnesene. Examples of the
conjugated diene other than farnesene as the component from which the
constitutional unit (b2) is derived include butadiene, isoprene,
2,3-dimethylbutadiene, 2-phenylbutadiene,
1,3-pentadiene,
2-methyl-1,3-pentadiene, 1,3-hexadiene, 1,3-octadiene, 1,3-cyclohexadiene,
2-methyl-1,3-octadiene, 1,3,7-octatriene, myrcene and chloroprene. These
conjugated dienes other than farnesene may be used alone or in combination of
any two or more thereof. Of these conjugated dienes, preferred is at least one
compound selected from the group consisting of butadiene, isoprene and
myrcene, and more preferred is at least one compound selected from the group
consisting of butadiene and isoprene.
[0014]
<Other Constitutional Unit (c)>
The aforementioned copolymer may also contain the other
constitutional unit (c) in addition to the constitutional units (a), OW and
(b2).
Examples of compounds as a component from which the other
constitutional unit (c) is derived include unsaturated hydrocarbon compounds
such as propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-
octene,
1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene,
1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene and 1-eicosene,
functional group-containing unsaturated compounds such as acrylic acid,
methacrylic acid, methyl acrylate, methyl methacrylate, acrylonitrile,
methacrylonitrile, maleic acid, fumaric acid, crotonic acid, itaconic acid,
2-acryloylethanesulfonic acid, 2-methacryloylethanesulfonic
acid,
2-acrylamide-2-methylpropanesulfonic
acid,
2-methacrylamide-2-methylpropanesulfonic acid, vinylsulfonic acid, vinyl
acetate and methyl vinyl ether; and the like. These other constitutional units
(c) may be used alone or in combination of any two or more thereof.
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[0015]
<Copolymer>
The copolymer of the present invention contains the aforementioned
constitutional unit (a) derived from the aromatic vinyl compound and the
aforementioned constitutional unit (b) derived from the conjugated diene.
Meanwhile, the copolymer may further contain the aforementioned
constitutional unit (c).
The total content of the constitutional unit (a) and the constitutional
unit (b) in the copolymer is preferably not less than 60% by mass, more
preferably not less than 80% by mass, still more preferably not less than 90%
by mass, and even still more preferably not less than 99% by mass, from the
viewpoint of improving a viscosity index and a high-temperature high-shear
viscosity of oils.
In addition, from the same viewpoint as described above, the content of
the constitutional unit (c) in a whole amount of the constitutional units
constituting the copolymer is preferably not more than 40% by mass, more
preferably not more than 20% by mass, still more preferably not more than 10%
by mass, and even still more preferably not more than 1% by mass.
The content of the constitutional unit (a) in the copolymer is preferably
from 1 to 99% by mass, more preferably from 2 to 90% by mass, still more
preferably from 3 to 85% by mass, even still more preferably from 5 to 80% by
mass, further even still more preferably from 10 to 50% by mass, and further
even still more preferably from 15 to 45% by mass, from the viewpoint of
improving a viscosity index and a high-temperature high-shear viscosity of
oils.
The mass ratio of a whole amount of the constitutional unit (a) to a
whole amount of the constitutional unit (b) [(a)/(b)] is preferably from 1/99
to
99/1, more preferably from 2/98 to 90/10, still more preferably from 3/97 to
85/15, even still more preferably from 5/95 to 80/20, further even still more
preferably from 10/90 to 50/50, and further even still more preferably from
15/85 to 45/55, from the viewpoint of improving a viscosity index and a
high-temperature high-shear viscosity of oils.
The copolymer of the present invention may be in the form of either a
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=
block copolymer or a random copolymer. Next, these two kinds of copolymers
are explained.
[0016]
(Block Copolymer)
The copolymer of the present invention may be in the form of a block
copolymer including a polymer block (A) containing the constitutional unit (a)
derived from the aromatic vinyl compound as a main component and a polymer
block (B) containing the constitutional unit (b) derived from the conjugated
diene as a main component.
The expression "as a main component" as used herein means that the
content of the constitutional unit (a) derived from the aromatic vinyl
compound
on the basis of a total mass of the polymer block (A) is not less than 50% by
mass, preferably not less than 70% by mass, and more preferably not less than
90% by mass, and also means that the content of the constitutional unit (b)
derived from the conjugated diene on the basis of a total mass of the polymer
block (B) is not less than 50% by mass, preferably not less than 65% by mass,
and more preferably not less than 80% by mass.
[0017]
The polymer block (B) preferably contains from 1 to 100% by mass of
the constitutional unit (b1) derived from farnesene and from 99 to 0% by mass
of the constitutional unit (b2) derived from the conjugated diene other than
farnesene. The preferred specific examples and content ratios of the
constitutional units (bl) and (b2) are the same as described above.
[0018]
Furthermore, the polymer block (b) may also contain a small amount of
a constitutional unit derived from any other copolymerizable monomer unless
the object and effects of the present invention are adversely affected.
Examples of the other copolymerizable monomer include anion-polymerizable
copolymerizable monomers, e.g., aromatic vinyl compounds such as styrene,
a-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene,
1,3-dimethylstyrene, diphenylethylene, 1-vinylnaphthalene, 4-propylstyrene,
4-cyclohexylstyrene, 4-dodecylstyrene, 2-ethyl-4-benzylstyrene
and
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4-(phenylbutypstyrene. These other copolymerizable monomers may be used
.alone or in combination of any two or more thereof. In the case where the
polymer block contains the constitutional unit derived from the other
copolymerizable monomer, the constitutional unit may be bonded thereto either
5 in a random form or in a tapered form.
In the case where the polymer block (b) contains the constitutional unit
derived from the other copolymerizable monomer, the content of the
constitutional unit derived from the other copolymerizable monomer in the
polymer block is preferably not more than 35% by mass, more preferably not
10 more than 10% by mass, and still more preferably not more than 5% by
mass.
[00191
The bonding configuration of each of the polymer block (A) and the
polymer block (B) is not particularly limited, and may be either a linear
configuration, a branched configuration, a radial configuration or a
combination of any two or more of these configurations. Of these bonding
configurations, when representing the polymer block (A) and the polymer block
(B) by A and B, respectively, from the viewpoint of improving a viscosity
index
and a high-temperature high-shear viscosity of oils, preferred are the bonding
configuration in which the respective polymer blocks are linearly bonded to
each other, and which is represented by (A-B)1, A-(B-A). or B-(A-B)n wherein
1,
m and n are each independently an integer of 1 or more, and the bonding
configuration in which the respective polymer blocks are radially bonded to
each other, and which is represented by (A-B)pX or (B-AX wherein p and q are
each independently an integer of 3 or more, and X is a residue of a coupling
reagent.
Of these copolymers having the above bonding configurations, from the
viewpoints of improving a viscosity index and a high-temperature high-shear
viscosity of oils, preferred are a di-block copolymer having the bonding
configuration represented by A-B or a tri-block copolymer having the bonding
configuration represented by A-B-A.
In addition, in the case where the block copolymer contains two or more
polymer blocks (A) or two or more polymer blocks (B), the two or more polymer
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blocks (A) or (B) may be respectively polymer blocks containing the same
.constitutional unit or polymer blocks containing different kinds of
constitutional units from each other. For example, in the two polymer blocks
(A) present in the tri-block copolymer represented by [A-B-A], the respective
aromatic vinyl compounds contained therein may be constituted of either the
same kind of compound or different kinds of compounds.
[0020]
The peak top molecular weight of the polymer block (A) is preferably
not less than 10,000 and not more than 60,000, and more preferably not less
than 15,000 and not more than 50,000, from the viewpoints of attaining a good
effect of improving a viscosity index of oils and facilitating production of
an oil
composition. When the peak top molecular weight of the polymer block (A) is
less than 10,000, the effect of improving a viscosity index of oils tends to
be
deteriorated. On the other hand, when the peak top molecular weight of the
polymer block (A) is more than 60,000, the resulting block copolymer tends to
be deteriorated in solubility in oils, and therefore there is a possibility
that no
effect of improving a viscosity index of oils is attained. Meanwhile, when the
block copolymer contains the two or more polymer blocks (A), the peak top
molecular weight of at least one of the polymer blocks (A) preferably falls
within the above-specified range.
Also, it is more preferred that the aforementioned block polymer
contains at least one polymer block selected from the group consisting of the
polymer block (A) and a polymer block (A') each containing the constitutional
unit (a) derived from the aromatic vinyl compound as a main component, and
the polymer block (B) containing the constitutional unit (b) derived from the
conjugated diene as a main component, in which the bonding configuration of
these polymer blocks in the block copolymer is A-B or A-B-A', and the peak top
molecular weight of the polymer block (A') is not less than 1,000 and less
than
10,000. The peak top molecular weight of the polymer block (A') is still more
preferably not less than 1,000 and not more than 8,000. When the peak top
molecular weight of the polymer block (A') is less than 10,000, the obtained
hydrogenated block copolymer can be prevented from forming a gel-like
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network in an oil composition, and the oil composition obtained therefrom can
be prevented from suffering from increase in kinetic viscosity thereof as
measured at a temperature of each of 40 C and 100 C. As a result, the use of
,
the oil composition as a lubricating oil is facilitated.
The peak top molecular weight of each of the polymer blocks (A) and
(A') can be determined by sampling a part of a reaction solution during
synthesis of the block copolymer and measuring a peak top molecular weight of
the respective polymer blocks of the block copolymer in the sampled reaction
solution by the method described below in Examples.
[0021]
(Random Copolymer)
Further, the copolymer of the present invention may be in the form of a
random copolymer containing the constitutional unit (a) derived from the
aromatic vinyl compound, the constitutional unit (b1) derived from farnesene,
and the constitutional unit (b2) derived from the conjugated diene other than
farnesene, which are randomly polymerized with each other.
[0022]
<Hydrogenated Copolymer>
The hydrogenated copolymer constituting the viscosity index improver
of the present invention is produced by hydrogenating the aforementioned
copolymer in which 50 mol% or more of carbon-carbon double bonds in the
constitutional unit (b) derived from the conjugated diene are hydrogenated,
namely the hydrogenated copolymer has a hydrogenation rate of 50 mol% or
more.
The hydrogenation rate as used herein is the value represented by the
following formula:
Hydrogenation rate = (1 - M2/M1) x 100 (mol%)
wherein M1 is a molar number of double bonds derived from the conjugated
diene which are contained per 1 mole of the copolymer; and M2 is a molar
number of double bonds derived from the conjugated diene which are contained
per 1 mole of the hydrogenated copolymer.
The hydrogenation rate is preferably not less than 60 mol%, and more
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_
preferably not less than 70 mol%, from the viewpoint of improving a heat
resistance and a shear stability of oils as well as a viscosity index and a
.
high-temperature high-shear viscosity of oils. Meanwhile, the hydrogenation
,
rate may be determined by the method described below in Examples.
[0023]
The peak top molecular weight (Mp) of the hydrogenated copolymer is
preferably from 4,000 to 1,500,000, more preferably from 9,000 to 1,200,000,
still more preferably from 20,000 to 1,100,000, and most preferably from
100,000 to 800,000, from the viewpoints of facilitating production of an oil
composition and improving a viscosity index of oils.
Meanwhile, the peak top molecular weight (Mp) as used in the present
specification means the value measured by the method described below in
Examples.
[0024]
The molecular weight distribution (Mw/Mn) of the hydrogenated
copolymer is preferably from 1 to 4, more preferably from 1 to 3, and still
more
preferably from 1 to 2. When the molecular weight distribution of the
hydrogenated copolymer falls within the above-specified range, the resulting
hydrogenated block copolymer can exhibit a less variation in viscosity
thereof.
[0025]
[Process for Producing Hydrogenated Copolymer]
The hydrogenated copolymer may be suitably produced by a process
including a polymerization step of obtaining the copolymer containing the
constitutional unit (a) derived from the aromatic vinyl compound and the
constitutional unit (b) derived from the conjugated diene by anionic
polymerization; and a hydrogenation step of hydrogenating 50 mol% or more of
carbon-carbon double bonds in the constitutional unit (b) derived from the
conjugated diene. The hydrogenation step may be carried out by the same
method as used in the hydrogenation step in the below-mentioned process for
producing the hydrogenated block copolymer.
Next, the process for producing the hydrogenated block copolymer is
described in more detail below.
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[0026]
process for Producing Hydrogenated Block Copolymer]
The hydrogenated block copolymer may be suitably produced by a
process including a polymerization step of obtaining a block copolymer
including a polymer block (A) containing the constitutional unit (a) derived
from the aromatic vinyl compound as a main component and a polymer block
(B) containing the constitutional unit (b) derived from the conjugated diene
as a ,
main component by anionic polymerization; and a hydrogenation step of
hydrogenating 50 mol% or more of carbon-carbon double bonds in the
constitutional unit (b) derived from the conjugated diene.
[0027]
Polymerization Step>
The block copolymer may be produced by any suitable polymerization
methods such as a solution polymerization method or the methods described in
JP 2012-502135A and JP 2012-502136A, in particular, is preferably produced
by the solution polymerization method. For example, various conventionally
known polymerization methods including an ionic polymerization method such
as an anionic polymerization method and a cationic polymerization method, a
radical polymerization method or the like may be applied thereto. Of these
methods, the anionic polymerization method is preferably used. In the anionic
polymerization method, the aromatic vinyl compound, and farnesene and/or the
conjugated diene other than farnesene are preferably sequentially added in the
presence of a solvent and an anionic polymerization initiator as well as, if
required, a Lewis base as an optional component, thereby obtaining the block
copolymer.
Examples of the anionic polymerization initiator include alkali metals
such as lithium, sodium and potassium; alkali earth metals such as beryllium,
magnesium, calcium, strontium and barium; lanthanoid-based rare earth
metals such as lanthanum and neodymium; and compounds containing the
above alkali metals, alkali earth metals or lanthanoid-based rare earth
metals.
Of these anionic polymerization initiators, preferred are the alkali metals,
the
compounds containing the alkali metals, and organic alkali metal compounds.
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[0028]
Specific examples of the organic alkali metal compounds include
organic lithium compounds such as methyl lithium, ethyl lithium, n-butyl
lithium, sec-butyl lithium, t-butyl lithium, hexyl lithium, phenyl lithium,
5 stilbene lithium, dilithiomethane, dilithionaphthalene, 1,4-dilithiobutane,
1,4-dilithio-2-ethyl cyclohexane and 1,3,5-trilithiobenzene; and sodium
naphthalene and potassium naphthalene, etc. Among these organic alkali
metal compounds, preferred are organic lithium compounds; more preferred
are n-butyl lithium and sec-butyl lithium; and still more preferred is sec-
butyl
10
lithium. Meanwhile, the organic alkali metal compound may be reacted with
a secondary amine such as diisopropylamine, dibutylamine, dihexylamine and
dibenzylamine to use the compound in the form of an organic alkali metal
amide.
The amount of the organic alkali metal compound used for the
15
polymerization may vary depending upon a molecular weight of the resulting
block copolymer, and is usually in the range of from 0.01 to 3% by mass on the
basis of a total amount of the aromatic vinyl compound, and farnesene and/or
the conjugated diene other than farnesene.
[0029]
The solvent used in the polymerization step is not particularly limited
unless it adversely affects the anionic polymerization reaction. Examples of
the solvent used in the polymerization step include saturated aliphatic
hydrocarbons such as n-pentane, isopentane, n-hexane, n-heptane and
isooctane; saturated alicyclic hydrocarbons such as cyclopentane, cyclohexane
and methyl cyclopentane; and aromatic hydrocarbons such as benzene, toluene
and xylene. These solvents may be used alone or in combination of any two or
more thereof. The amount of the solvent used in the polymerization step is not
particularly limited.
[0030]
The Lewis base acts for controlling a microstructure of each of the
constitutional unit (b1) derived from farnesene and the constitutional unit
(b2)
derived from the conjugated diene other than farnesene. Examples of the
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Lewis base include ether compounds such as dibutyl ether, diethyl ether,
.tetrahydrofuran, dioxane and ethylene glycol diethyl ether; pyridine;
tertiary
amines such as N,N,N',N'-tetramethyl ethylenediamine and trimethylamine;
alkali metal alkoxides such as potassium-t-butoxide; and phosphine compounds.
The amount of the Lewis base, if used, is usually preferably in the range of
from
0.01 to 1,000 mol equivalent on the basis of 1 mol of the anionic
polymerization
initiator.
[0031]
The temperature used in the above polymerization reaction is usually
from -80 to 150 C, preferably from 0 to 100 C and more preferably from 10 to
90 C. The polymerization reaction may be carried out by either a batch
method or a continuous method. The respective monomers, i.e., the aromatic
vinyl compound, and farnesene and/or the conjugated diene other than
farnesene may be supplied to the polymerization reaction solution in a
continuous or intermittent manner such that the abundance ratio of each of the
aromatic vinyl compound, and farnesene and/or the conjugated diene other
than farnesene in the polymerization reaction system falls within a specific
range, or the aromatic vinyl compound, and farnesene and/or the conjugated
diene other than farnesene may be sequentially polymerized such that the ratio
=
of the respective monomers in the polymerization reaction solution is
controlled
to a specific range, whereby it is possible to produce the block copolymer.
The polymerization reaction may be stopped by adding an alcohol such
as methanol and isopropanol as a terminating reagent to the reaction system.
The resulting polymerization reaction solution may be poured into a poor
solvent such as methanol to precipitate the block copolymer. Alternatively,
there may be used the method in which the polymerization reaction solution is
rinsed with water, and then the obtained reaction product is separated from
the
water layer and dried to isolate the block copolymer therefrom.
[0032]
{Modified Copolymer}
In the polymerization step, the block copolymer can be obtained in the
form of an unmodified block copolymer as described above. However, the block
CA 02888668 2015-04-17
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copolymer may also be in the form of a modified block copolymer obtained by
.
,the following method.
The above block copolymer may be modified prior to the
,
below-mentioned hydrogenation step. Examples of a functional group that
may be introduced into the block copolymer include an amino group, an
alkoxysilyl group, a hydroxyl group, an epoxy group, a carboxyl group, a
carbonyl group, a mercapto group, an isocyanate group and an acid anhydride
group.
As the method of modifying the block copolymer, there may be used, for
example, the method in which before adding the terminating reagent, a
coupling reagent such as tin tetrachloride, tetrachlorosilane,
dimethyldichlorosilane, dimethyldiethoxysilane,
tetramethoxysilane,
tetraethoxysilane,
3-aminopropyltriethoxysilane,
tetraglycidy1-1,3-bisaminomethylcyclohexane and 2,4-tolylene diisocyanate
which are capable of reacting with an active end of the polymer chain, a chain
end-modifying reagent such as 4,4'-bis(diethylamino)benzophenone and
N-vinylpyrrolidone, or the other modifying reagent as described in JP
2011-132298A is added to the polymerization reaction system. Furthermore,
the isolated copolymer may be grafted with maleic anhydride or the like.
The site of the block polymer into which the functional group is
introduced may be either a chain end or a side chain of the polymer. In
addition, these functional groups may be used alone or in combination of any
two or more thereof. The modifying reagent is usually preferably used in an
amount of from 0.01 to 10 mol equivalent on the basis of the anionic
polymerization initiator used in the polymerization step.
[0033]
<Hydrogenation Step>
When the block copolymer obtained by the above method is subjected to
hydrogenation step, it is possible to produce the hydrogenated block
copolymer.
As the hydrogenation method, there may be used conventionally known
methods. For example, a solution prepared by dissolving the block copolymer
in a solvent that has no adverse influence on the hydrogenation reaction is
CA 02888668 2015-04-17
18
subjected to hydrogenation reaction in the presence of a hydrogenation
catalyst.
.Examples of the hydrogenation catalyst include Ziegler-based catalysts;
metal-supported catalysts obtained by supporting a metal such as nickel,
platinum, palladium, ruthenium and rhodium on a carrier such as carbon,
silica and diatomaceous earth; and organic metal complexes containing a metal
such as cobalt, nickel, palladium, rhodium and ruthenium.
In the
hydrogenation step, the hydrogenation reaction may be carried out by adding
the hydrogenation catalyst to the polymerization reaction solution containing
the block copolymer obtained by the above method for producing the block
copolymer. In the present invention, there is preferably used palladium
carbon formed by supporting palladium on carbon.
In the hydrogenation reaction, a hydrogen pressure used therein is
preferably from 0.1 to 20 MPa, the reaction temperature is preferably from 100
to 200 C, and the reaction time is preferably from 1 to 20 h.
[0034]
The hydrogenation rate of carbon-carbon double bonds in the polymer
block (B) contained in the block copolymer is preferably not less than 50
mol%,
more preferably not less than 60 mol%, and still more preferably not less than
70 mol%, from the viewpoint of improving a heat resistance and a shear
stability of oils as well as a viscosity index and a high-temperature high-
shear
viscosity of oils. Meanwhile, the hydrogenation rate may be calculated by the
method described below in Examples.
[0035]
[Oil Composition]
The oil composition of the present invention includes a base oil and the
aforementioned viscosity index improver.
The oil composition may be suitably used as an engine oil, an automatic
transmission oil, a gear lube oil and a hydraulic pressure oil.
The content of the viscosity index improver in the oil composition is
preferably from 0.05 to 10% by mass, more preferably from 0.1 to 7% by mass,
still more preferably from 0.2 to 5% by mass, and even still more preferably
from 0.5 to 5% by mass.
CA 02888668 2015-04-17
19
[0036]
.<Base Oil>
Examples of the base oil include fuel oils such as intermediate fraction
fuels, synthetic or natural lubricating oils, unrefined oils and industrial
oils.
The base oil may be at least one compound selected from the group consisting
of
a paraffin-based compound, a naphthene-based compound and an aromatic
compound. In addition, the base oil may also be at least one oil selected from
the group consisting of a natural oil and an artificially synthesized oil.
<Other Additives>
The oil composition of the present invention may also contain other
additives such as a rust preventive, an antioxidant, a surfactant, a pour
point
depressant, a cleaning dispersant, a metal deactivator, a defoamer, a friction
controller, an extreme pressure reagent and one or more additional viscosity
index improvers.
<Method of Producing Oil Composition>
The oil composition of the present invention may be produced by
methods conventionally known in the art.
For example, the oil composition of the present invention may be
produced by mixing the aforementioned base oil with the aforementioned
viscosity index improver. The mixing of these components may be carried out
using conventionally known mixers.
The mixing is preferably carried out while heating. The heating
temperature is preferably from 80 to 180 C.
[0037]
In the case where the oil composition of the present invention is applied
to an engine oil, an automatic transmission oil, a gear lube oil, a hydraulic
pressure oil or the like, the kinetic viscosity thereof as measured at 40 C is
preferably in the range of from 40 to 120 mm2/sec, and more preferably from 50
to 70 mm2/sec. In addition, from the same viewpoint, the kinetic viscosity of
the oil composition of the present invention as measured at 100 C is
preferably
in the range of from 6 to 25 mm2/sec, and more preferably from 8 to 15
mm2/sec.
When the kinetic viscosity of the oil composition lies within the above-
specified
CA 02888668 2015-11-18
73162-286PPH
range, the oil composition is capable of reducing a fuel consumption in
vehicles
when used in the above applications.
Examples
5 (0038]
The present invention will be described in more detail below by
referring to the following examples. It should be noted, however, that the
following examples are only illustrative and not intended to limit the
invention
thereto. Meanwhile, 6-farnesene (purity: 97.6% by mass; available from
10 Amyris Biotechnologies Inc.) was purified using a 3 A molecular sieve and
distilled under a nitrogen atmosphere to remove hydrocarbon-based impurities
such as zingiberene, bisabolene, famesene epoxide, farnesol isomers,
E,E-farnesol, squalene, ergosterol and several kinds of dimers of farnesene
therefrom, and the thus purified 0-farnesene was used in the following
15 polymerization.
[0039]
(1) Measurement of Molecular Weight Distribution (Mw/Mn) and Peak Top
Molecular Weight (Mp)
The weight-average molecular weight (Mw) and the molecular weight
20 distribution (Mw/Mn) of each of the hydrogenated block copolymers
produced in
the respective Examples and Comparative Examples were measured by GPC
(gel permeation chromatography) in terms of a molecular weight of polystyrene
as a reference standard substance. Also, the peak top molecular weight (Mp)
of the hydrogenated block copolymer was determined from a position of a peak
top of the molecular weight distribution (Mw/Mn). The measuring devices and
conditions used in the above measurement are as follows.
= Apparatus: GPC device "GPC8020" available from T3soh Corp.
= Separating column: "TSKge1TmG4000HXL" available from Tosoh Corp.
= Detector: "RI-8020" available from 'Ibsoh Corp.
= Eluent: Ibtrahydrofuran
= Eluent flow rate: 1.0 mL/min
= Sample concentration: 5 mg/10 mL
CA 02888668 2015-11-18
73162-286PPH
21
= Column temperature: 40 C
[0040]
(2) Method of Measuring Hydrogenation Rate
In the respective Examples and Comparative Examples, the block
copolymer and the hydrogenated block copolymer obtained after hydrogenating
the block copolymer were respectively dissolved in a deuterated chloroform
solvent, and each of the resulting solutions was subjected to 1H-NMR
measurement at 50 C using "LambdaTm-500" available form JOEL Ltd. The
hydrogenation rate of the polymer block (B) in the hydrogenated block
copolymer was calculated from the peak of protons contained in carbon-carbon
double bonds observed in the range of from 4.5 to 6.0 ppm in the resulting
spectrum, according to the following formula.
Hydrogenation Rate = {1 - (number of moles of carbon-carbon double
bonds contained per 1 mole of hydrogenated block copolymer)/(number of moles
of carbon-carbon double bonds contained per 1 mole of block copolymer} x 100
(mol%)
[00411
(3) Kinetic Viscosity
The kinetic viscosity was measured at a temperature of each of 40 C
and 100 C according to JIS K2283.
(4) Viscosity Index
The viscosity index was measured according to JIS K2283.
(5) High-Temperature High-Sear Viscosity
The high-temperature high-shear viscosity was measured at a
temperature of 150 C according to ASTM D4683.
[0042]
[Example 11
A pressure reaction vessel previously purged with nitrogen and then
dried was charged with 62.4 kg of cyclohexane as a solvent and 61.0 g of
sec-butyl lithium an the form of a 10.5% by mass cyclohexane solution) as an
anionic polymerization initiator. The contents of the reaction vessel were
heated. to 50 C, and then 2.34 kg of styrene (1) was added. thereto, followed.
by
CA 02888668 2015-11-18
73162-286PPH
22
polymerizing the contents of the reaction vessel for 1 h. Successively, 10.9
kg
of 0-farnesene was added to the reaction vessel, followed by polymerizing the
contents of the reaction vessel for 2 h. Furthermore, 2.34 kg of styrene (2)
was
added to the reaction vessel, followed by polymerizing the contents of the
reaction vessel for 1 h, thereby obtaining a reaction solution containing a
polystyrene-poly(0-farnesene)-polystyrene triblock copolymer. Added into the
reaction solution was palladium carbon (amount of palladium supported: 5% by
mass) as a hydrogenation catalyst which was used in an amount of 5% by mass
on the basis of the block copolymer, and the block copolymer was subjected to
hydrogenation reaction under a hydrogen pressure of 2 MPa at a temperature
of 150 C for 10 h. The obtained reaction mixture was allowed to stand for
cooling and pressure releasing, and then subjected to filtration to remove the
palladium carbon therefrom. The resulting filtrate was concentrated and
further vacuum-dried, thereby obtaining a hydrogenated product of the
polystyrene-poly(0-farnesene)-polystyrene triblock copolymer (hereinafter
referred to as a "hydrogenated block copolymer (A1)"). The formulations of
various raw materials used above and the results of measurement of various
properties of the thus obtained hydrogenated block copolymer (A1) are shown
in Table 1 below.
The resulting hydrogenated block copolymer (A1) and a paraffin-based
oil "DIANA FRESIATM S-32" available from Idemitsu Kosan Co., Ltd., were used
as a viscosity index improver and a base oil, respectively, and the
hydrogenated
block copolymer (A1) and the base oil were formulated as shown in Table 2.
These components were mixed in a pressure reaction vessel purged with
nitrogen at a temperature of 120 C at a rotating speed of 350 rpm for 6 h,
thereby obtaining an oil composition. The thus obtained oil composition was
subjected to the above evaluation. The results are shown in Table 2.
[0043]
[Example 21
A pressure reaction vessel previously purged with nitrogen and then
dried was charged with 62.4 kg of cyclohexane as a solvent and 40.6 g of
sec-butyl lithium (in the form of a 10.5% by mass cyclohexane solution) as an
CA 02888668 2015-04-17
23
anionic polymerization initiator. The contents of the reaction vessel were
.heated to 50 C, and then 13.0 kg of (3-farnesene was added thereto, followed
by
polymerizing the contents of the reaction vessel for 2 h. Successively, 2.59
kg
of styrene was added to the reaction vessel, followed by polymerizing the
contents of the reaction vessel for 1 h, thereby obtaining a reaction solution
containing a poly(f3-farnesene)-polystyrene diblock copolymer. Added into the
reaction solution was palladium carbon (amount of palladium supported: 5% by
mass) as a hydrogenation catalyst which was used in an amount of 5% by mass
on the basis of the block copolymer, and the block copolymer was subjected to
hydrogenation reaction under a hydrogen pressure of 2 MPa at a temperature
of 150 C for 10 h. The obtained reaction mixture was allowed to stand for
cooling and pressure releasing, and then subjected to filtration to remove the
palladium carbon therefrom. The resulting filtrate was concentrated and
further vacuum-dried, thereby obtaining a hydrogenated product of the
poly(P-farnesene)-polystyrene diblock copolymer (hereinafter referred to as a
"hydrogenated block copolymer (A2)"). The formulations of various raw
materials used above and the results of measurement of various properties of
the thus obtained hydrogenated block copolymer (A2) are shown in Table 1
below.
The subsequent procedure was conducted in the same manner as in
Example 1 except that the resulting hydrogenated block copolymer (A2) and
the base oil were formulated as shown in Table 2, thereby obtaining an oil
composition. The thus obtained oil composition was subjected to the above
evaluation. The results are shown in Table 2.
[0044]
[Example 31
The same procedure as in Example 2 was repeated except that the
respective components were formulated as shown in Table 1, thereby obtaining
a hydrogenated block copolymer (A3) and an oil composition and subjecting the
resulting products to the above evaluation. The results are shown in Tables 1
and 2.
[0045]
CA 02888668 2015-04-17
24
[Example 4]
. The same procedure as in Example 1 was repeated except that the
respective components were formulated as shown in Table 1, thereby obtaining
a hydrogenated block copolymer (A4) and an oil composition and subjecting the
resulting products to the above evaluation. The results are shown in Tables 1
and 2.
[0046]
[Example 51
A pressure reaction vessel previously purged with nitrogen and then
dried was charged with 62.4 kg of cyclohexane as a solvent and 118.4 g of
sec-butyl lithium (in the form of a 10.5% by mass cyclohexane solution) as an
anionic polymerization initiator. The contents of the reaction vessel were
heated to 50 C, and then a mixture of 5.43 kg of 13-farnesene and 4.32 kg of
butadiene was added thereto, followed by polymerizing the contents of the
reaction vessel for 2 h. Successively, 5.85 kg of styrene was added to the
reaction vessel, followed by polymerizing the contents of the reaction vessel
for
1 h, thereby obtaining a reaction solution containing a
poly(f3-farnesene/butadiene)-polystyrene diblock copolymer. Added into the
reaction solution was palladium carbon (amount of palladium supported: 5% by
mass) as a hydrogenation catalyst which was used in an amount of 5% by mass
on the basis of the block copolymer, and the block copolymer was subjected to
hydrogenation reaction under a hydrogen pressure of 2 MPa at a temperature
of 150 C for 10 h. The obtained reaction mixture was allowed to stand for
cooling and pressure releasing, and then subjected to filtration to remove the
palladium carbon therefrom. The resulting filtrate was concentrated and
further vacuum-dried, thereby obtaining a hydrogenated product of the
poly(13-farnesene/butadiene)-polystyrene diblock copolymer (hereinafter
referred to as a "hydrogenated block copolymer (A5)"). The formulations of
various raw materials used above and the results of measurement of various
properties of the thus obtained hydrogenated block copolymer (A5) are shown
in Table 1 below.
The subsequent procedure was conducted in the same manner as in
CA 02888668 2015-04-17
Example 1 except that the resulting hydrogenated block copolymer (A5) and
the base oil were formulated as shown in Table 2, thereby obtaining an oil
composition. The thus obtained oil composition was subjected to the above
evaluation. The results are shown in Table 2.
5 [00471
[Example 61
The same procedure as in Example 5 was repeated except that the
hydrogenated block copolymer (A5) and the base oil were formulated as shown
in Table 2, thereby obtaining an oil composition. The thus obtained oil
10 composition was subjected to the above evaluation. The results are shown
in
Table 2.
[0048]
[Example 7]
A pressure reaction vessel previously purged with nitrogen and then
15 dried was charged with 62.4 kg of cyclohexane as a solvent and 104.9 g
of
sec-butyl lithium (in the form of a 10.5% by mass cyclohexane solution) as an
anionic polymerization initiator. The contents of the reaction vessel were
heated to 50 C, and then a mixture of 4.88 kg of 13-farnesene and 4.88 kg of
isoprene was added thereto, followed by polymerizing the contents of the
20 reaction vessel for 2 h. Successively, 5.85 kg of styrene was added to the
reaction vessel, followed by polymerizing the contents of the reaction vessel
for
1 h, thereby obtaining a reaction solution containing a
poly(P-farnesene/isoprene)-polystyrene diblock copolymer. Added into the
reaction solution was palladium carbon (amount of palladium supported: 5% by
25 mass) as a hydrogenation catalyst which was used in an amount of 5% by
mass
on the basis of the block copolymer, and the block copolymer was subjected to
hydrogenation reaction under a hydrogen pressure of 2 MPa at a temperature
of 150 C for 10 h. The obtained reaction mixture was allowed to stand for
cooling and pressure releasing, and then subjected to filtration to remove the
palladium carbon therefrom. The resulting filtrate was concentrated and
further vacuum-dried, thereby obtaining a hydrogenated product of the
poly(13-farnesene/isoprene)-polystyrene diblock copolymer (hereinafter
referred
CA 02888668 2015-04-17
26
to as a "hydrogenated block copolymer (A6)"). The formulations of various raw
materials used above and the results of measurement of various properties of
the thus obtained hydrogenated block copolymer (A6) are shown in Table 1
below.
The subsequent procedure was conducted in the same manner as in
Example 1 except that the resulting hydrogenated block copolymer (A6) and
the base oil were formulated as shown in Table 2, thereby obtaining an oil
composition. The thus obtained oil composition was subjected to the above
evaluation. The results are shown in Table 2.
[0049]
[Example 8]
The same procedure as in Example 7 was repeated except that the
hydrogenated block copolymer (A6) and the base oil were formulated as shown
in Table 2, thereby obtaining an oil composition. The thus obtained oil
composition was subjected to the above evaluation. The results are shown in
Table 2.
[0050]
[Comparative Example 11
A pressure reaction vessel previously purged with nitrogen and then
dried was charged with 62.4 kg of cyclohexane as a solvent and 98.6 g of
sec-butyl lithium (in the form of a 10.5% by mass cyclohexane solution) as an
anionic polymerization initiator. The contents of the reaction vessel were
heated to 50 C, and then 8.36 kg of isoprene was added thereto, followed by
polymerizing the contents of the reaction vessel for 2 h. Successively, 5.34
kg
of styrene was added to the reaction vessel, followed by polymerizing the
contents of the reaction vessel for 1 h, thereby obtaining a reaction solution
containing a polyisoprene-polystyrene diblock copolymer. Added into the
reaction solution was palladium carbon (amount of palladium supported: 5% by
mass) as a hydrogenation catalyst which was used in an amount of 5% by mass
on the basis of the block copolymer, and the block copolymer was subjected to
hydrogenation reaction under a hydrogen pressure of 2 MPa at a temperature
of 150 C for 10 h. The obtained reaction mixture was allowed to stand for
CA 02888668 2015-04-17
27
cooling and pressure releasing, and then subjected to filtration to remove the
,palladium carbon therefrom. The resulting filtrate was concentrated and
further vacuum-dried, thereby obtaining a hydrogenated product of the
polyisoprene-polystyrene diblock copolymer (hereinafter referred to as a
"hydrogenated block copolymer (B1)"). The formulations of various raw
materials used above and the results of measurement of various properties of
the thus obtained hydrogenated block copolymer (B1) are shown in Table 1
below.
The subsequent procedure was conducted in the same manner as in
Example 1 except that the resulting hydrogenated block copolymer (B1) was
used as a viscosity index improver, thereby obtaining an oil composition. The
thus obtained oil composition was subjected to the above evaluation. The
results are shown in Table 2.
[0051]
[Comparative Example 2]
The same procedure as in Comparative Example 1 was repeated except
that the hydrogenated block copolymer (B1) and the base oil were formulated
as shown in Table 2, thereby obtaining an oil composition. The thus obtained
oil composition was subjected to the above evaluation. The results are shown
in Table 2.
[0052]
[Comparative Example 3]
The same procedure as in Comparative Example 1 was repeated except
that the respective components were formulated as shown in Table 1, thereby
obtaining a hydrogenated block copolymer (B2) and an oil composition and
subjecting the resulting products to the above evaluation. The results are
shown in Tables 1 and 2.
[0053]
[Comparative Example 4]
A pressure reaction vessel previously purged with nitrogen and then
dried was charged with 62.4 kg of cyclohexane as a solvent, 79.4 g of sec-
butyl
lithium (in the form of a 10.5% by mass cyclohexane solution) as an anionic
CA 02888668 2015-04-17
28
polymerization initiator and 375 g of tetrahydrofuran as a Lewis base. The
. contents of the reaction vessel were heated to 50 C, and then 0.47 kg of
styrene
(1) was added thereto, followed by polymerizing the contents of the reaction
vessel for 1 h. Successively, a mixture of 6.86 kg of isoprene and 6.86 kg of
butadiene was added to the reaction vessel, followed by polymerizing the
contents of the reaction vessel for 2 h. Further, 1.40 kg of styrene (2) was
added to the reaction vessel, followed by polymerizing the contents of the
reaction vessel for 1 h, thereby obtaining a reaction solution containing a
polystyrene-poly(isoprene/butadiene)-polystyrene triblock copolymer. Added
into the reaction solution was palladium carbon (amount of palladium
supported: 5% by mass) as a hydrogenation catalyst which was used in an
amount of 5% by mass on the basis of the block copolymer, and the block
copolymer was subjected to hydrogenation reaction under a hydrogen pressure
of 2 MPa at a temperature of 150 C for 10 h. The obtained reaction mixture
was allowed to stand for cooling and pressure releasing, and then subjected to
filtration to remove the palladium carbon therefrom. The resulting filtrate
was concentrated and further vacuum-dried, thereby obtaining a hydrogenated
product of the polystyrene-poly(isoprene/butadiene)-polystyrene triblock
copolymer (hereinafter referred to as a "hydrogenated block copolymer (B3)").
The formulations of various raw materials used above and the results of
measurement of various properties of the thus obtained hydrogenated block
copolymer (B3) are shown in Table 1 below.
The subsequent procedure was conducted in the same manner as in
Example 1 except that the resulting hydrogenated block copolymer (B3) and
the base oil were formulated as shown in Table 2, thereby obtaining an oil
composition. The thus obtained oil composition was subjected to the above
evaluation. The results are shown in Table 2.
[0054]
[Comparative Example 51
Only the base oil, i.e., the paraffin-based oil "DIANA FRESIA S-32"
available from Idemitsu Kosan Co., Ltd., was used as such in Comparative
Example 5, and subjected to the above evaluation. The results are shown in
CA 02888668 2015-04-17
29
=
Table 2.
=
=
=
30
[0055]
TABLE 1
Hydrogenated block copolymers
Hydrogenated block
copolymers
A1 A2 A3 A4 A5
A6 B1 B2 B3
Amounts used [kg]
Cyclohexane 62.4 62.4 62.4 62.4
62.4 62.4 62.4 62.4 62.4
sec-Butyl lithium 0.0510 0.0406 0.1080 0.1124 0.1184
0.1049 0.0986 0.0921 0.0794
Styrene (1) 2.34 2.59 5.85 0.77
5.85 5.85 5.34 5.14 0.47
Styrene (2) 2.34 5.39
1.40 p
p - Farne s e n e 10.9 13.0 9.75 9.44
5.43 4.88
Butadiene
4.32 6.86
Isoprene
4.88 8.36 8.56 6.86
Tetrahydrofuran
0.375
_
(b1)/(b) PA by mass] (*1.) 100 100 100 100 56
50 0 0 0
_
(a)/(b) [mass ratio] (*2) 30/70 17/83 37.5/ 39.5/
37.5/ 37.5/ 39/61 37.5/ 12/88
62.5 60.5
62.5 62.5 62.5
Polymer skeleton (*3) St-F-St F-St F-St St-F-St F/Bd-St
F/IP-St IP-St IP-St St-IP/Bd-St
Properties
Peak top molecular weight (Mp) 228,000 244,000 92,000 91,700 109,200
118,500 122,000 137,000 165,000
Peak top molecular weight of styrene block 28,800 40,000 33,900 30,100
35,000 31,000 34,000 35,000 3,500
(1)
Peak top molecular weight of styrene block 28,800 - 4,300
11,000
(2)
Molecular weight distribution 1.13 1.13 1.06 1.04 1.05 1.03 1.03 1.05 1.06
(Mw/Mn)
Hydrogenation rate [ /0] (*4) 90.6 91.5 91.7 91.8
98.7 99.0 99.4 99.1 87.0
31
Note (*1) (b1)/(b): Content of a constitutional unit (bl) derived from
farnesene in a whole amount of a constitutional unit (b)
derived from a conjugated diene.
(*2): (a)/(b): Mass ratio of a whole amount of a constitutional unit (a) to a
whole amount of a constitutional unit (b).
(*3): St-F-St: Polystyrene-poly([3-farnesene)-polystyrene triblock copolymer.
F- St: Po1y(13-farnesene)-polystyrene diblock copolymer.
F/Bd-St: Poly(13-farnesene/butadiene)-polystyrene diblock copolymer.
F/IP-St: Poly(f3-farnesene/isoprene)-polystyrene diblock copolymer.
IP-St: Polyisoprene -polystyrenediblock copolymer.
St-IP/Bd-St: Polystyrene-polyisoprene/polybutadiene-polystyrene triblock
copolymer.
(*4): Hydrogenation rate of carbon-carbon double bonds in a constitutional
unit (b) derived from a conjugated diene.
32
4
[0056]
TABLE 2
Examples
Comparative Examples
1 = 2 3 4 5 6 7
8 1 2 3 4 5
Base oil
DIANA FRESIA S-32 (mass%) 99 99 98 98 98.5 98
98.5 98 _ 99 98 99 99 100
Viscosity index improver
Hydrogenated block copolymer (A1) 1
(mass%)
Hydrogenated block copolymer (A2) 1
(mass%)
Hydrogenated block copolymer (A3) 2
(mass%)
Hydrogenated block copolymer (A4) 2
(mass%)
Hydrogenated block copolymer (A5) 1.5 2
0
(mass%)
=
Hydrogenated block copolymer (A6) 1.5 2
=(mass%)
Hydrogenated block copolymer (B1)
1 2
(mass%)
Hydrogenated block copolymer (B2)
1
(mass%)
Hydrogenated block copolymer (B3)
1
(mass%)
Evaluation
Kinetic viscosity (at 40 C) (mm2/s) 114.7 64.0 54.7 55.0 55.8
65.5 56.0 65.9 56.7 229.0 61.9 57.8 31.2
Kinetic viscosity (at 100 C) (mm2/s) 23.5 10.6 9.2 9.6 9.4
10.8 9.3 10.7 9.2 31.6 10.0 8.6 5.4
Viscosity index (VI) 237 155 147 160 152 156
148 152 144 179 147 84 105
High-temperature high-shear viscosity 2.8 2.8 2.8 2.8 2.8
3.3 2.8 3.2 2.7 4.1 2.8 2.8 2.0
(HTHS) (mPa = s)
CA 02888668 2015-04-17
33
[0057]
From the results shown in Tables 1 and 2, it was confirmed that the
= hydrogenated block copolymers obtained in Examples 1 to 8 were excellent
in
an effect of improving a viscosity index and a high-temperature high-shear
viscosity of oils even though they were viscosity index improvers produced
from
a plant-derived raw material (f3-farnesene), and it was also confirmed that
the
hydrogenated block copolymers of these Examples were excellent in an effect of
improving a viscosity index of oils to an extent identical to or higher than
those
attained by using the hydrogenated block copolymers obtained in Comparative
Examples 1 to 4. Furthermore, the hydrogenated block copolymers obtained
in Examples 2 to 8 exhibited a sufficiently reduced kinetic viscosity as
measured at a temperature of each of 40 C and 100 C, and therefore also
excellent in an effect of saving a fuel consumption in automobiles.
