CATALYST FOR CONJUGATED DIENE POLYMERIZATION, CONJUGATED
DIENE POLYMER AND MODIFIED CONJUGATED DIENE POLYMER PRODUCED USING THE SAME, PRODUCTION METHODS THEREOF, RUBBER COMPOSITION FOR TIRE, AND RUBBER COMPOSITION FOR RUBBER BELT
Technical Field
The present invention relates to a catalyst for a
conjugated diene polymerization containing a nonmetallocene type gadolinium compound, a conjugated diene
polymer and a modified conjugated diene polymer produced using the same, production methods thereof, a rubber composition for a tire, and a rubber composition for a rubber belt.
Background Art
[0002]
Various catalysts for a polymerization of a
conjugated diene, such as 1,3-butadiene and isoprene,
have conventionally been proposed, and some of them have
been industrialized. For example, in production methods
of a conjugated diene polymer having high cis-1,4
structures, combinations of a compound of a metal such as
titanium, cobalt, nickel or neodymium with an organic
aluminum compound are often used.
[0003]
3
In addition, polymerizations of a conjugated diene
using a catalyst containing a group 3 element of the
periodic table are known, and various polymerization
methods have hitherto been proposed. For example, Patent
Literature 1 discloses a catalyst system including a salt
of a rare earth metal, an organic metal compound of a
group I to III element of the periodic table, and a
fluorine-containing organic boron compound. Patent
Literature 2 discloses a polymerization catalyst
including a compound of a group IIIB metal of the
periodic table, an ionic compound of a non-coordinating
anion and a cation, and an organic metal compound of a
group I to III element of the periodic table. Patent
Literature 3 lists organic metal compounds including an
element selected from groups 2, 12 and 13 of the periodic
table. In addition, Patent Literatures 4 to 6 report
polymerizations of a conjugated diene using a metallocene
type gadolinium complex.
Among the catalysts described in Patent Literatures
1 to 3, however, ones showing their effects in Examples
are mainly neodymium-based catalysts, and gadolinium
compounds have not yet been made clear. In addition, the
catalysts described in Patent Literatures 4 to 6 have
defects that they have low catalytic activities of at
most 540 g/mmol-Gd/hr.
[0004]
4
A rubber composition containing a polybutadiene
rubber (BR) or a styrene-butadiene rubber (SBR) as a main
component, and including, in addition, a natural rubber,
and the like has conventionally been industrially
produced and used mainly as a material for a tire, a
crawler for a crawler type traveling apparatus, an
industrial rubber belt, or the like, utilizing its
characteristic (Patent Literatures 7 and 8).
[0005]
Requirements for reducing fuel consumption in
automobiles and requirements for running safety on snow
and ice have recently been increased for tire materials,
and thus it has been desired to develop a rubber material
having a low rolling resistance, (i.e., a high rebound
resilience) and a large grip on a road surface such as a
snow or ice surface (i.e., a high wet skid resistance).
However, rubbers having a high rebound resilience such as
a polybutadiene rubber (BR) are likely to have a lower
wet skid resistance; whereas a styrene-butadiene rubber
(SBR) has a defect in which the wet skid resistance is
high, but the rolling resistance is also high. In order
to solve the problems described above, various methods in
which a low cis-diene-based rubber is chemically modified
with a modifier in the presence of a lithium catalyst
have been proposed, but the low cis-BR has an
insufficient abrasion resistance, and this problem cannot
be solved even by the modification. In addition, the SBR
5
also has a low rebound resilience, and this defect cannot
be solved even after the modification.
[0006]
Patent Literature 9 discloses, as an example of a
modification of a high cis-diene-based rubber, a method
in which cis-1,4-polybutadiene is produced using a
titanium compound having a cyclopentadienyl backbone as a
catalyst, and then the product is modified by reacting it
with 4,4'-bis(diethylamino)benzophenone, but the
resulting product has a very small ratio of a weight
average molecular weight (Mw) to a number average
molecular weight (Mn), (Mw/Mn), of less than 1.5, thus
resulting in a problem of processability.
[0007]
A crawler type traveling apparatus, which is used
in every field, such as a bulldozer, is configured by
winding an endless belt-shaped elastic crawler around a
drive sprocket, an idler, and multiple trunk rollers. It
is often used in harsher conditions than those in wheels,
and crawler structures have been improved in order to
increase a running performance and durability. In
addition, rubber compositions for a crawler, which are
tougher, have a higher durability, and are excellent in
low fuel consumption are required.
[0008]
It is required, for a rubber composition used for a
rubber belt, to have a high tensile strength, a moderate
6
hardness, a softness, an elasticity, a high flexibility,
and a high impact resistance, and further energy saving
and weight saving are also required. In order to satisfy
these requirements, reinforcement using an inorganic
reinforcing agent or short fiber is proposed. In order
to increase the hardness, tensile stress, breakage
strength, abrasion resistance, and the like, however, if
the amount is increased by addition of an inorganic
reinforcing agent such as carbon black, then dynamic heat
generation is increased, and a problem in which the
weight saving is not attained is raised because of an
increased specific gravity of the formulation. The
rubber composition described in Patent Literature 8 has a
problem in which the composition cannot necessarily
obtain sufficient effects in the tensile stress and the
elongation fatigue resistance, because microfine
dispersion of 1,2-polybutadiene short fiber crystals in
the butadiene rubber, which is a matrix component, is
insufficient.
[0009]
As for the polybutadiene, a vinylcis-polybutadiene
in which syndiotactic 1,2-polybutadiene (hereinafter may
sometimes be referred to as SPB) is dispersed in high
cis-BR (hereinafter may sometimes be referred to as VCR)
is known as a BR having higher functional characteristics,
which utilizes the characteristics of the high cis-BR.
[0010]
7
As the production method of VCR described above,
for example, Patent Literatures 10 and 11 disclose
methods for producing an SPB-containing high cis-BR
composite using a cobalt catalyst. Patent Literature 12
discloses a method for producing an SPB-containing high
cis-BR composite using a nickel catalyst.
[0011]
In addition, Patent Literature 13 discloses a
method for producing VCR in an inert organic solvent
including mainly a C4 fraction such as n-butane, cis-2-
butene, trans-2-butene, or butene-1. However, a method
for producing VCR using a gadolinium catalyst has not yet
been reported.
Citation List
Patent Literatures
[0012]
Patent Literature 1: JP 7-268013 A
Patent Literature 2: JP 11-80222 A
Patent Literature 3: JP 2007-161921 A
Patent Literature 4: JP 2004-27179 A
Patent Literature 5: JP 2004-238637 A
Patent Literature 6: JP 2007-63240 A
Patent Literature 7: JP 2007-230266 A
Patent Literature 8: JP 2004-346220 A
Patent Literature 9: JP 2000-86719 A
Patent Literature 10: JP 49-17666 B
8
Patent Literature 11: JP 49-17667 B
Patent Literature 12: JP 63-1324 B
Patent Literature 13: JP 2000-44633 B
Summary of Invention
Technical Problem
[0013]
In view of the problems described above, the
present invention has been made, and it is an object of
the present invention to provide a catalyst for a
conjugated diene polymerization containing a gadolinium
compound, which can produce a conjugated diene polymer
having a high content of cis-1,4 structures with a high
activity.
[0014]
Furthermore, it is an object of the present
invention to provide a conjugated diene polymer, a
modified conjugated diene polymer, and a vinylcispolybutadiene
(VCR), which have a high content of cis-1,4
structures, produced using the above-mentioned gadolinium
catalyst easy to handle and having a high activity;
production methods thereof; and a conjugated diene
polymer composition and a modified conjugated diene
polymer composition containing these polymers.
[0015]
Furthermore, it is an object of the present
invention to provide a rubber composition for a tire and
9
a tire, which are tough, have excellent durability of an
elongation fatigue resistance and an abrasion resistance,
have a reduced energy loss, and can be used for a
crawler; and a rubber composition for a rubber belt and a
rubber belt, which are preferable for an industrial
rubber belt.
Solution to Problem
[0016]
In order to attain the objects described above, the
present inventors have intensively researched; as a
result, they have found that when a non-metallocene type
gadolinium compound is used, a conjugated diene polymer
having a high content of cis-1,4 structures can be
produced with a higher activity than those in
conventional methods, and have reached the present
invention.
[0017]
Furthermore, they have also found that when the
gadolinium compound described above is used, a conjugated
diene polymer and a modified conjugated diene polymer,
which have a very high content of cis-1,4 structures, can
be produced, and have reached the present invention.
[0018]
Furthermore, they have also found that when the
conjugated diene polymer or the modified conjugated diene
polymer described above is used, a conjugated diene
10
polymer composition having excellent rebound resilience
and abrasion resistance, and a modified conjugated diene
polymer composition having an excellent elongation
fatigue resistance, in addition to the above, can be
produced, and have reached the present invention.
[0019]
Furthermore, they have also found that when a
polybutadiene having a high content of cis-1,4 structures
is produced with a high activity using the gadolinium
compound described above, and then a SPB is synthesized
in the polymerization system, vinylcis-polybutadiene
(VCR) can be favorably produced, and have reached the
present invention.
[0020]
Furthermore, they have also found that a rubber
composition for a tire and a tire using the conjugated
diene polymer or the modified conjugated diene polymer
are tough, have excellent durability of elongation
fatigue resistance, abrasion resistance, and the like,
have a reduced energy loss, and can be used for a
crawler; and a rubber composition for a rubber belt and a
rubber belt using the conjugated diene polymer or the
modified conjugated diene polymer described above, are
preferable for an industrial rubber belt, and have
reached the present invention.
[0021]
11
According to the present invention, there is
provided a catalyst for a conjugated diene polymerization
including: a non-metallocene type gadolinium compound (A)
represented by the following general formula (1); an
ionic compound (B) formed of a non-coordinating anion and
a cation; and an organic metal compound (C) of an element
selected from the group consisting of a group 2, a group
12, and a group 13 of the periodic table.
[0022]
[Chemical Formula 1]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
[0023]
In the catalyst for a conjugated diene
polymerization of the present invention, the organic
metal compound (C) is preferably an organic aluminum
compound, and the ionic compound (B) is preferably a
boron-containing compound.
[0024]
Furthermore, according to the present invention,
there is provided a method for producing a conjugated
diene polymer including polymerizing a conjugated diene
12
compound using the catalyst for a conjugated diene
polymerization.
[0025]
Furthermore, according to the present invention,
there is provided a method for producing a modified
conjugated diene polymer including: polymerizing a
conjugated diene compound using a catalyst for a
conjugated diene polymerization including a nonmetallocene
type gadolinium compound (A) represented by
the following general formula (1), an ionic compound (B)
formed of a non-coordinating anion and a cation, and an
organic metal compound (C) of an element selected from
the group consisting of group 2, a group 12, and a group
13 of the periodic table to obtain a conjugated diene
polymer; and modifying the conjugated diene polymer with
an amino group-containing carbonyl compound to obtain a
modified conjugated diene polymer.
[0026]
[Chemical Formula 2]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
[0027]
13
In the method for producing a modified conjugated
diene polymer of the present invention, the amino groupcontaining
carbonyl compound is preferably a 4,4'-bisdialkylaminobenzophenone,
and it is preferable to adjust
the molecular weight using a compound selected from (1) a
hydrogen, (2) a metal hydride compound, and (3) a
hydrogenated organic metal compound in the polymerization
of the conjugated diene compound.
[0028]
Furthermore, according to the present invention,
there is provided a method for producing a modified
conjugated diene polymer including: polymerizing a
conjugated diene compound using a catalyst for a
conjugated diene polymerization containing a nonmetallocene
type gadolinium compound (A) represented by
the following general formula (1), an ionic compound (B)
formed of a non-coordinating anion and a cation, and an
organic metal compound (C) of an element selected from
the group consisting of a group 2, a group 12, and a
group 13 of the periodic table to obtain a conjugated
diene polymer; and modifying the conjugated diene polymer
with a halogenated benzyl compound to obtain a modified
conjugated diene polymer.
[0029]
[Chemical Formula 3]
14
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
[0030]
In the method for producing a modified conjugated
diene polymer of the present invention, the halogenated
benzyl compound is preferably a piperonyl chloride, a
dimethoxybenzyl bromide, or a methoxybenzyl chloride, and
it is preferable to adjust the molecular weight with a
compound selected from (1) a hydrogen, (2) a metal
hydride compound, and (3) a hydrogenated organic metal
compound in the polymerization of the conjugated diene
compound.
[0031]
Furthermore, according to the present invention,
there is provided a method for producing a modified
conjugated diene polymer, which includes: polymerizing a
conjugated diene compound using a catalyst for a
conjugated diene polymerization containing a nonmetallocene
type gadolinium compound (A) represented by
the following general formula (1), an ionic compound (B)
formed of a non-coordinating anion and a cation, and an
organic metal compound (C) of an element selected from
15
the group consisting of a group 2, a group 12, and a
group 13 of the periodic table to obtain a conjugated
diene polymer; and modifying the conjugated diene polymer
with an aldehyde compound to obtain a modified conjugated
diene polymer.
[0032]
[Chemical Formula 4]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
[0033]
In the method for producing a modified conjugated
diene polymer of the present invention, the aldehyde
compound is preferably a heliotropin or a veratrum
aldehyde, and it is preferable to adjust the molecular
weight with a compound selected from the group consisting
of (1) a hydrogen, (2) a metal hydride compound, and (3)
a hydrogenated organic metal compound in the
polymerization of the conjugated diene compound.
[0034]
Furthermore, according to the present invention,
there is provided a method for producing a vinylcispolybutadiene,
which includes performing a cis-1,4
16
polymerization of a 1,3-butadiene, and performing a
subsequent syndiotactic-1,2 polymerization in the
resulting polymerization system, wherein a catalyst for a
conjugated diene polymerization containing a nonmetallocene
type gadolinium compound (A) represented by
the following general formula (1), an ionic compound (B)
formed of a non-coordinating anion and a cation, and an
organic metal compound (C) of an element selected from
the group consisting of a group 2, a group 12, and a
group 13 of the periodic table is used as a catalyst in
the cis-1,4 polymerization, and a catalyst system
containing a sulfur compound is used as a catalyst in the
syndiotactic-1,2 polymerization.
[0035]
[Chemical Formula 5]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
[0036]
In the production method of the vinylcispolybutadiene
of the present invention, the organic metal
compound (C) is preferably an organic aluminum compound,
the ionic compound (B) is preferably a boron-containing
17
compound, and it is preferable to use a catalyst system
containing a cobalt compound, a trialkyl aluminum
compound, and a sulfur compound as the catalyst in the
syndiotactic-1,2 polymerization.
[0037]
Furthermore, according to the present invention,
there is provided vinylcis-polybutadiene obtained by a
production method, which includes performing a cis-1,4
polymerization of 1,3-butadiene using a catalyst for a
conjugated diene polymerization containing a nonmetallocene
type gadolinium compound (A) represented by
the following general formula (1), an ionic compound (B)
formed of a non-coordinating anion and a cation, and an
organic metal compound (C) of an element selected from
the group consisting of a group 2, a group 12, and a
group 13 of the periodic table; and performing a
syndiotactic-1,2 polymerization using a catalyst system
containing a sulfur compound in the resulting
polymerization system.
[0038]
[Chemical Formula 6]
18
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
[0039]
Furthermore, according to the present invention,
there is provided a conjugated diene polymer composition
including: a conjugated diene polymer () resulting from
a polymerization of a conjugated diene compound using a
catalyst for a conjugated diene polymerization containing
a non-metallocene type gadolinium compound (A)
represented by the following general formula (1), an
ionic compound (B) formed of a non-coordinating anion and
a cation, and an organic metal compound (C) of an element
selected from the group consisting of a group 2, a group
12, and a group 13 of the periodic table; a diene polymer
() other than the (); and a rubber-reinforcing agent
().
[0040]
[Chemical Formula 7]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
[0041]
19
In the conjugated diene polymer composition of the
present invention, the rubber-reinforcing agent () is
preferably a carbon black, it is preferable to adjust the
molecular weight of the conjugated diene compound with a
compound selected from the group consisting of (1) a
hydrogen, (2) a metal hydride compound, (3) a
hydrogenated organic metal compound, and the conjugated
diene compound is preferably a 1,3-butadiene.
[0042]
Furthermore, according to the present invention,
there is provided a modified conjugated diene polymer
composition including: a modified conjugated diene
polymer (’) obtained by polymerizing a conjugated diene
compound using a catalyst for a conjugated diene
polymerization containing a non-metallocene type
gadolinium compound (A) represented by the following
general formula (1), a ionic compound (B) formed of a
non-coordinating anion and a cation, and an organic metal
compound (C) of an element selected from the group
consisting of a group 2, a group 12, and a group 13 of
the periodic table, and then modifying the resulting
polymer with an amino group-containing carbonyl compound;
a diene polymer () other than the ('); and a rubberreinforcing
agent ().
[0043]
[Chemical Formula 8]
20
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
[0044]
In the modified conjugated diene polymer
composition of the present invention, the rubberreinforcing
agent () is preferably a carbon black, the
amino group-containing carbonyl compound is preferably a
4,4’-bis-dialkylaminobenzophenone, it is preferable to
adjust the molecular weight of the conjugated diene
compound with a compound selected from the group
consisting of (1) a hydrogen, (2) a metal hydride
compound, and (3) a hydrogenated organic metal compound,
and the conjugated diene compound is preferably a 1,3-
butadiene.
[0045]
Furthermore, according to the present invention,
there is provided a rubber composition for a tire
including: rubber components () + (); and a rubberreinforcing
agent (), wherein the rubber-reinforcing
agent () is included in an amount of 30 to 80 parts by
mass based on 100 parts by mass of the rubber components
() + (). The rubber components () is a conjugated
21
diene polymer () obtained by polymerizing a conjugated
diene compound using a catalyst for a conjugated diene
polymerization containing a non-metallocene type
gadolinium compound (A) represented by the following
general formula (1), an ionic compound (B) formed of a
non-coordinating anion and a cation, and an organic metal
compound (C) of an element selected from the group
consisting of a group 2, a group 12, and a group 13 of
the periodic table. The rubber component () is a diene
polymer () other than the ().
[0046]
[Chemical Formula 9]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
[0047]
Furthermore, according to the present invention,
there is provided a rubber composition for a tire
including: rubber components (') + (); and a rubberreinforcing
agent (), wherein the rubber-reinforcing
agent () is included in an amount of 30 to 80 parts by
mass based on 100 parts by mass of the rubber components
(') + (). The rubber component (') is a modified
22
conjugated diene polymer (') obtained by polymerizing a
conjugated diene compound using a catalyst for a
conjugated diene polymerization containing a nonmetallocene
type gadolinium compound (A) represented by
the following general formula (1), an ionic compound (B)
formed of a non-coordinating anion and a cation, and an
organic metal compound (C) of an element selected from
the group consisting of a group 2, a group 12, and a
group 13 of the periodic table. The rubber component ()
is a diene polymer () other than the (').
[0048]
[Chemical Formula 10]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
[0049]
In the rubber composition for a tire of the present
invention, the diene polymer () other than the () and
(') is preferably a natural rubber and/or a
polyisoprene, and the rubber-reinforcing agent (F) is
preferably a carbon black.
[0050]
23
Furthermore, according to the present invention,
there is provided a tire using the rubber composition for
a tire as a rubber substrate.
[0051]
Furthermore, according to the present invention,
there is provided a rubber composition for a rubber belt
including: rubber components () + (); and a rubberreinforcing
agent (), wherein the rubber-reinforcing
agent () is included in an amount of 20 to 70 parts by
mass based on 100 parts by mass of the rubber components
() + (). The rubber component () is a conjugated
diene polymer () obtained by polymerizing a conjugated
diene compound using a catalyst for a conjugated diene
polymerization containing a non-metallocene type
gadolinium compound (A) represented by the following
general formula (1), an ionic compound (B) formed of a
non-coordinating anion and a cation, and an organic metal
compound (C) of an element selected from the group
consisting of a group 2, a group 12, and a group 13 of
the periodic table. The rubber component () is a diene
polymer () other than the ().
[0052]
[Chemical Formula 11]
24
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
[0053]
Furthermore, according to the present invention,
there is provided a rubber composition for a rubber belt
including: rubber components (') + (); and a rubberreinforcing
agent (), wherein the rubber-reinforcing
agent () is included in an amount of 20 to 70 parts by
mass based on 100 parts by mass of the rubber components
(') + (). The rubber component (') is a modified
conjugated diene polymer (') obtained by polymerizing a
conjugated diene compound using a catalyst for a
conjugated diene polymerization containing a nonmetallocene
type gadolinium compound (A) represented by
the following general formula (1), an ionic compound (B)
formed of a non-coordinating anion and a cation, and an
organic metal compound (C) of an element selected from
the group consisting of a group 2, a group 12, and a
group 13 of the periodic table, and then modifying the
resulting polymer. The rubber component () is a diene
polymer () other than the (').
[0054]
[Chemical Formula 12]
25
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
[0055]
In the rubber composition for a rubber belt of the
present invention, the rubber-reinforcing agent () is
preferably a carbon black and/or a silica, and it is more
preferable that the rubber-reinforcing agent () is a
carbon black and a silica and the silica is included in
an amount of 70% by mass or less in the rubberreinforcing
agent.
[0056]
Furthermore, according to the present invention,
there is provided a rubber belt using the rubber
composition for a rubber belt as a rubber substrate.
Advantageous Effects of Invention
[0057]
As described above, according to the present
invention, there can be provided a catalyst for a
conjugated diene polymerization capable of producing a
conjugated diene polymer having a high content of cis-
1,4-structures with a high activity.
26
[0058]
In addition, according to the present invention,
there can be provided a conjugated diene polymer, a
modified conjugated diene polymer, and a vinylcispolybutadiene
(VCR), which have a very high content of
cis-1,4 structures, using the catalyst which is easy to
handle and have a high activity, and production methods
thereof. There can be also provided a conjugated diene
polymer composition, which has an improved filler
dispersibility, and excellent rebound resilience and
abrasion resistance, and a modified conjugated diene
polymer composition, which has an excellent elongation
fatigue resistance in addition to the above.
[0059]
Furthermore, according to the present invention,
there can be provided a rubber composition for a tire and
a tire, which are tough, have excellent durability of
elongation fatigue resistance and abrasion resistance,
have a reduced energy loss, and can be used for a crawler,
and a rubber composition for a rubber belt and a rubber
belt preferable for an industrial rubber belt.
Brief Description of Drawing
[0060]
Fig. 1 is a graph showing a relationship between a
UV/RI value and (1/Mn) × 104 for obtaining a degree of
modification of the modified conjugated diene polymer of
27
the present invention. In this figure, UV denotes a peak
area obtained from a UV absorbance at 274 nm obtained in
a GPC measurement of a polymer, and RI denotes a peak
area obtained from a differential refractive index. In
addition, Mn denotes a number average molecular weight.
Description of Embodiments
[0061]
(Catalyst for Conjugated Diene Polymerization)
The non-metallocene type gadolinium compound (A)
used in the catalyst for a conjugated diene
polymerization in the present invention is a nonmetallocene
type gadolinium compound represented by the
following general formula (1):
[0062]
[Chemical Formula 13]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
[0063]
Specific examples of the substituent having 1 to 12
carbon atoms in R1 to R3 in the general formula (1) may
include saturated hydrocarbon groups such as a methyl
28
group, an ethyl group, an n-propyl group, an isopropyl
group, an n-butyl group, an s-butyl group, an isobutyl
group, a t-butyl group, an n-pentyl group, a 1-
methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl
group, a 1,1-dimethylpropyl group, a 1,2-dimethylpropyl
group, a 2,2-dimethylpropyl group, a hexyl group, a
heptyl group, an octyl group, a nonyl group, a decyl
group, an undecyl group, and a dodecyl group; unsaturated
hydrocarbon groups such as a vinyl group, a 1-propenyl
group, and an allyl group; alicyclic hydrocarbon groups
such as a cyclohexyl group, a methylcyclohexyl group, and
an ethylcyclohexyl group; aromatic hydrocarbon groups
such as a phenyl group, a benzil group, a toluyl group,
and a phenethyl group, and the like. The substituent may
also include groups which are substituted by a hydroxyl
group, a carboxyl group, a carbomethoxy group, a
carboethoxy group, an amide group, an amino group, an
alkoxy group, a phenoxy group or the like at any position.
Of these, saturated hydrocarbon groups having 1 to 12
carbon atoms are preferable, and saturated hydrocarbon
groups having 1 to 6 carbon atoms are particularly
preferable.
[0064]
Specific examples of the non-metallocene type
gadolinium compound (A) may include tris(2,2,6,6-
tetramethyl-3,5-heptanedionato)gadolinium, tris(2,6,6-
trimethyl-3,5-heptanedionato)gadolinium, tris(2,6-
29
dimethyl-3,5-heptanedionato)gadolinium, tris(3,5-
heptanedionato)gadolinium, tris(2,4-
pentanedionato)gadolinium, tris(2,4-
hexanedionato)gadolinium, tris(1,5-dicyclopentyl-2,4-
pentanedionato)gadolinium, tris(1,5-dicyclohexyl-2,4-
pentanedionato)gadolinium, and the like.
[0065]
Of these, preferable examples may include
tris(2,2,6,6-tetramethyl-3,5-heptanedionato)gadolinium,
tris(2,6-dimethyl-3,5-heptanedionato)gadolinium,
tris(2,4-pentanedionato)gadolinium, and the like.
Particularly preferable examples may include
tris(2,2,6,6-tetramethyl-3,5-heptanedionato)gadolinium,
and tris(2,6-dimethyl-3,5-heptanedionato)gadolinium. The
non-metallocene type gadolinium compound (A) may be used
alone or as a mixture of two or more kinds.
[0066]
The non-metallocene type gadolinium compound (A)
can be used as a catalyst for a conjugated diene
polymerization in combination with the ionic compound (B)
including a non-coordinating anion and a cation, and the
organic metal compound (C) of an element selected from
the group consisting of a group 2, a group 12, and a
group 13 of the periodic table.
[0067]
In the component (B), or the ionic compound
including the non-coordinating anion and the cation, the
30
non-coordinating anion may include, for example,
tetra(phenyl)borate, tetra(fluorophenyl)borate,
tetrakis(difluorophenyl)borate,
tetrakis(trifluorophenyl)borate,
tetrakis(tetrafluorophenyl)borate,
tetrakis(pentafluorophenyl)borate, tetrakis(3,5-bistrifluoromethylphenyl)
borate,
tetrakis(tetrafluoromethylphenyl)borate,
tetra(triyl)borate, tetra(xylyl)borate,
triphenyl(pentafluorophenyl)borate,
tris(pentafluorophenyl)(phenyl)borate, tridecahydride-
7,8-dicarbaundecaborate, tetrafluoroborate,
hexafluorophosphate, and the like.
[0068]
The cation may include a carbonium cation, an
oxonium cation, an ammonium cation, a phosphonium cation,
a cycloheptatrienyl cation, a ferrocenium cation, and the
like.
[0069]
Specific examples of the carbonium cation may
include tri-substituted carbonium cations such as
triphenylcarbonium cation, and tri-substituted
phenylcarbonium cation. Specific examples of the trisubstituted
phenylcarbonium cation may include a
tri(methylphenyl)carbonium cation, and a
tri(dimethylphenyl)carbonium cation.
[0070]
31
Specific examples of the ammonium cation may
include trialkylammonium cations such as a
trimethylammonium cation, a triethylammonium cation, a
tripropylammonium cation, a tributylammonium cation, and
a tri(n-butyl)ammonium cation; N,N-dialkylanilinium
cations such as an N,N-dimethylanilinium cation, an N,Ndiethylanilinium
cation, and an N,N-2,4,6-
pentamethylanilinium cation; and dialkylammonium cations
such as a di(isopropyl)ammonium cation, and a
dicyclohexylammonium cation.
[0071]
Specific examples of the phosphonium cation may
include allylphosphonium cations such as a
triphenylphosphonium cation, a tetraphenylphosphonium
cation, a tri(methylphenyl)phosphonium cation, a
tetra(methylphenyl)phosphonium cation, a
tri(dimethylphenyl)phosphonium cation, and a
tetra(dimethylphenyl)phosphonium cation.
[0072]
Any combination, obtained by arbitrarily selecting
from the non-coordinating anions and the cations listed
above respectively, may be preferably used as the ionic
compound (B).
[0073]
Of these, a boron-containing compound is preferable
as the ionic compound (B), and triphenylcarbenium
tetrakis(pentafluorophenyl)borate, triphenylcarbenium
32
tetrakis(fluorophenyl)borate, N,N-dimethylanilinium
tetrakis(pentafluorophenyl)borate, and 1,1’-
dimethylferrocenium tetrakis(pentafluorophenyl)borate are
particularly preferable among them. The ionic compound
(B) may be used alone or as a mixture of two or more
kinds.
[0074]
Instead of the ionic compound formed of the noncoordinating
anion and the cation as the component (B),
an alumoxane may be used. The alumoxane is a compound
obtained by contacting an organic aluminum compound with
a condensing agent, which includes a linear alumoxane or
cyclic alumoxane represented by the general formula: (-
Al(R')O-)n wherein R' denotes a hydrocarbon group having
1 to 10 carbon atoms, including groups partially
substituted by a halogen atom and/or an alkoxy group; and
n is a degree of polymerization and 5 or more, preferably
10 or more. R' may include a methyl group, an ethyl
group, a propyl group and an isobutyl group, and methyl
group is preferable. An organic aluminum compound used
as a starting material of the alumoxane may include, for
example, trialkyl aluminum such as trimethyl aluminum,
triethyl aluminum, and triisobutyl aluminum, and mixtures
thereof, and the like. Of these, an alumoxane obtained
using a mixture of trimethyl aluminum and triisobutyl
aluminum can be preferably used.
[0075]
33
Typical condensing agent may be water, and in
addition it may include any agent capable of causing a
condensation reaction of the above-mentioned organic
aluminum compound, for example, adsorbed water in an
inorganic substance, diols, and the like.
[0076]
As the component (C), or the organic metal compound
of an element selected from the group consisting of a
group 2, a group 12, and a group 13 of the periodic table,
for example, an organic magnesium compound, an organic
zinc compound, an organic aluminum compound, and the like
are used. Among these compounds, a dialkyl magnesium;
alkyl magnesium halides such as an alkyl magnesium
chloride and an alkyl magnesium bromide; a dialkyl zinc;
a trialkyl aluminum; a dialkyl aluminum chloride, a
dialkyl aluminum bromide; organic aluminum halides such
as an alkyl aluminum sesqui-chloride, an alkyl aluminum
sesqui-bromide, and an alkyl aluminum dichloride;
hydrogenated organic aluminum compound such as a dialkyl
aluminum hydride are preferable.
[0077]
Specific compounds thereof may include alkyl
magnesium halides such as methyl magnesium chloride,
ethyl magnesium chloride, butyl magnesium chloride, hexyl
magnesium chloride, octyl magnesium chloride, ethyl
magnesium bromide, butyl magnesium bromide, butyl
magnesium iodide, and hexyl magnesium iodide.
34
[0078]
The compound may further include dialkyl magnesium
such as dimethyl magnesium, diethyl magnesium, dibutyl
magnesium, dihexyl magnesium, dioctyl magnesium, ethyl
butyl magnesium, and ethyl hexyl magnesium.
[0079]
Furthermore, the compound may include dialkyl zinc
such as dimethyl zinc, diethyl zinc, diisobutyl zinc,
dihexyl zinc, dioctyl zinc, and didecyl zinc.
[0080]
Furthermore, the compound may include trialkyl
aluminum such as trimethyl aluminum, triethyl aluminum,
triisobutyl aluminum, trihexyl aluminum, trioctyl
aluminum, and tridecyl aluminum.
[0081]
Furthermore, the compound may include dialkyl
aluminum chlorides such as dimethyl aluminum chloride and
diethyl aluminum chloride; organic aluminum halides such
as ethyl aluminum sesqui-chloride and ethyl aluminum
dichloride; hydrogenated organic aluminum compounds such
as diethyl aluminum hydride, diisobutyl aluminum hydride,
and ethyl aluminum sesqui-hydride.
[0082]
The organic metal compound (C) of an element
selected from the group consisting of a group 2, a group
12, and a group 13 of the periodic table may be used
alone or as a mixture of two or more kinds.
35
Of these, the group 13 elements are preferable, and
an organic aluminum compound is preferable among them.
Examples thereof may include trimethyl aluminum, triethyl
aluminum, triisobutyl aluminum, and the like. Triethyl
aluminum is particularly preferable.
[0083]
In the present invention, the polymerization of the
conjugated diene can be carried out using the catalyst
including the components (A), (B), and (C) described
above. In addition to the catalyst, a molecular weightadjusting
agent of the obtained conjugated diene polymer
may be added as long as the effects of the present
invention are not impaired.
[0084]
As the molecular weight-adjusting agent, a compound
selected from hydrogen, a metal hydride compound, and an
organic metal compound may be used.
[0085]
The metal hydride compound may include lithium
hydride, sodium hydride, potassium hydride, magnesium
hydride, calcium hydride, borane, aluminum hydride,
gallium hydride, silane, germane, lithium borohydride,
sodium borohydride, lithium aluminum hydride, sodium
aluminum hydride, and the like.
[0086]
The hydrogenated organic metal compound may include
alkyl borane such as methyl borane, ethyl borane,
36
propylborane, butyl borane, and phenyl borane; dialkyl
borane such as dimethyl borane, diethyl borane, dipropyl
borane, dibutyl borane, diphenyl borane; alkyl aluminum
dihydrides such as methyl aluminum dihydride, ethyl
aluminum dihydride, propyl aluminum dihydride, butyl
aluminum dihydride, and phenyl aluminum dihydride;
dialkyl aluminum hydrides such as dimethyl aluminum
hydride, diethyl aluminum hydride, dipropyl aluminum
hydride, di-normal-butyl aluminum hydride, diisobutyl
aluminum hydride, and diphenyl aluminum hydride; silanes
such as methyl silane, ethyl silane, propyl silane, butyl
silane, phenyl silane, dimethyl silane, diethyl silane,
dipropyl silane, dibutyl silane, diphenyl silane,
trimethyl silane, triethyl silane, tripropyl silane,
tributyl silane, and triphenyl silane; germanes such as
methyl germane, ethyl germane, propyl germane, butyl
germane, phenyl germane, dimethyl germane, diethyl
germane, dipropyl germane, dibutyl germane, diphenyl
germane, trimethyl germane, triethyl germane, tripropyl
germane, tributyl germane, and triphenyl germane, and the
like.
[0087]
Of these, diisobutyl aluminum hydride, and diethyl
aluminum hydride are preferable, and diisobutyl aluminum
hydride is particularly preferable.
[0088]
37
In the present invention, each catalyst component
may be previously aged and then used. It is especially
preferable that the component (A) and the component (C)
are aged.
[0089]
The aging is preferably performed by mixing the
component (A) and the component (C) in an inert solvent
in the presence or absence of the conjugated diene
compound monomers to be polymerized. The ageing
temperature is from 50 to 120C, preferably from 10 to
95C, and the ageing time is from 0.005 to 24 hours,
preferably from 0.01 to 5 hours, particularly preferably
from 0.02 to 1 hour.
[0090]
In the present invention, each catalyst component
may be supported on an inorganic compound or an organic
polymer compound, and then the resulting product can be
used.
[0091]
In the method for producing a conjugated diene
polymer according to the present invention, the addition
order of the catalyst components is not particularly
limited, and the components may be added, for example, in
the following orders:
[0092]
(1) The component (C) is added to an inert organic
solvent in the presence or absence of the conjugated
38
diene compound monomers to be polymerized, and then the
component (A) and the component (B) are added in an
arbitrary order.
[0093]
(2) The component (C) is added to an inert organic
solvent in the presence or absence of the conjugated
diene compound monomers to be polymerized, the molecular
weight-adjusting agent is added, and then the component
(A) and the component (B) are added in an arbitrary order.
[0094]
(3) The component (A) is added to an inert organic
solvent in the presence or absence of the conjugated
diene compound monomers to be polymerized, the component
(C) and the molecular weight-adjusting agent are added in
an arbitrary order, and then the component (B) is added.
[0095]
(4) The component (B) is added to an inert organic
solvent in the presence or absence of the conjugated
diene compound monomers to be polymerized, the component
(C) and the molecular weight-adjusting agent are added in
an arbitrary order, and then the component (A) is added.
[0096]
(5) The component (C) is added to an inert organic
solvent in the presence or absence of the conjugated
diene compound monomers to be polymerized, the component
(A) and the component (B) are added in an arbitrary order,
and then the molecular weight-adjusting agent is added.
39
[0097]
The conjugated diene compound monomer, which is a
starting material, may include 1,3-butadiene, isoprene,
1,3-pentadiene, 2-ethyl-1,3-butadiene, 2,3-dimethyl
butadiene, 2-methyl pentadiene, 4-methyl pentadiene, 2,4-
hexadiene, and the like. Of these, conjugated diene
compound monomers containing 1,3-butadiene as a main
component are preferable. The monomer component may be
used alone, or as a mixture of two or more kinds.
[0098]
Here, the conjugated diene compound monomers to be
polymerized may be a whole amount of the monomers or a
part of the monomers. In a case of a part of the
monomers, a contact mixture of the component containing
at least one of the components (A), (B), and (C), and the
monomers may be mixed with the rest monomer or a solution
of the rest monomer.
In addition to the conjugated diene, an olefin
compound such as ethylene, propylene, allene, 1-butene,
2-butene, 1,2-butadiene, penetene, cyclopentene, hexene,
cyclohexene, octene, cyclooctadiene, cyclododecatriene,
norbornene, or norbornadiene may be included.
[0099]
Polymerization methods are not particularly limited,
and mass polymerizations (bulk polymerizations) using
monomers of a conjugated diene compound such as 1,3-
butadiene themselves as a polymerization solvent, or
40
solution polymerizations are employed. The solvent used
in the solution polymerization may include aliphatic
hydrocarbons such as butane, pentane, hexane, and
heptane; alicyclic hydrocarbons such as cyclopentane, and
cyclohexane; aromatic hydrocarbons such as benzene,
toluene, xylene, ethyl benzene, and cumene; olefinic
hydrocarbons such as the olefinic compounds described
above, cis-2-butene, trans-2-butene, and the like. Of
these, benzene, toluene, xylene, cyclohexane, and a
mixture of cis-2-butene and trans-2-butene are preferably
used. The solvent may be used alone or as a mixture of
two or more kinds.
[0100]
The polymerization temperature is preferably within
a range of 30 to 150C, more preferably 0 to 100C,
particularly preferably 10 to 80C. The polymerization
time is preferably from one minute to 12 hours, more
preferably from 3 minutes to 5 hours, particularly
preferably from 5 minutes to one hour.
[0101]
After the polymerization is performed for a given
time, the pressure inside the polymerization tank is
released if necessary, and post-treatments such as
washing and drying are performed.
[0102]
The conjugated diene polymer obtained in the
present invention is exemplified by a cis-1,4-
41
polybutadiene containing preferably 94% or more, more
preferably 98% or more, particularly preferably 98.5% or
more, of cis-1,4 structures. The [] of the conjugated
diene polymer can be controlled to preferably from 0.1 to
10, more preferably from 1 to 7, particularly preferably
from 1.5 to 5.
[0103]
The conjugated diene polymer obtained in the
present invention has a number average molecular weight
(Mn) of preferably 10000 to 1000000, more preferably
100000 to 700000, particularly preferably 150000 to
550000. The conjugated diene polymer has a ratio of a
weight average molecular weight (Mw) and a number average
molecular weight (Mn), (Mw/Mn), of preferably 1.5 to 10,
more preferably 1.5 to 7, particularly preferably 1.5 to
4. When the Mw/Mn is small, the processability may
sometimes worsen.
[0104]
(Modified Conjugated Diene Polymer)
The conjugated diene polymer obtained in the
present invention can be modified, and additional effects
can be exhibited by the modification. It is preferable
in the present invention to use a modifier which is at
least one compound selected from the group consisting of
amino group-containing carbonyl compounds, halogenated
benzyl compounds, and aldehyde compounds.
[0105]
42
Aminobenzophenone compounds are preferable as a
carbonyl compound (preferably an aromatic carbonyl
compound) having an amino group (preferably an aminoalkyl
group having an alkyl group with 1 to 6 carbon atoms).
Specific compound examples thereof may include 4-dimethyl
aminoacetophenone, 4-diethyl aminoacetophenone, 4-
dimethyl aminopropiophenone, 4-diethyl aminopropiophenone,
1,3-bis(diphenylamino)-2-propanone, 1,7-
bis(methylethylamino)-4-heptanone, 4-dimethyl
aminobenzophenone, 4-diethyl aminobenzophenone, 4-dibutyl
aminobenzophenone, 4-diphenylaminobenzophenone, 4,4’-
bis(dimethylamino)benzophenone, 4,4’-
bis(diethylamino)benzophenone, 4,4’-
bis(dibutylamino)benzophenone, 4,4’-
bis(diphenylamino)benzophenone, 4-dimethyl
aminobenzaldehyde, 4-diphenyl aminobenzaldehyde, 4-
divinyl aminobenzaldehyde, and the like. Of these
compounds, 4,4’-bis(diethylamino)benzophenone is
particularly preferable. The modifier may be used alone
or as a mixture of two or more kinds.
[0106]
Alkoxybenzyl halide compounds are preferable as the
halogenated benzyl compound. Specific compound examples
thereof may include methoxybenzyl chloride, methoxybenzyl
bromide, methoxybenzyl iodide, ethoxybenzyl chloride,
ethoxybenzyl bromide, ethoxybenzyl iodide,
dimethoxybenzyl chloride, dimethoxybenzyl bromide,
43
dimethoxybenzyl iodide, diethoxybenzyl chloride,
diethoxybenzyl bromide, diethoxybenzyl iodide, piperonyl
chloride, piperonyl bromide, piperonyl iodide, and the
like. Of these compounds, methoxybenzyl chloride,
dimethoxybenzyl bromide, and piperonyl chloride are
particularly preferable. The modifier may be used alone
or as a mixture of two or more kinds.
[0107]
Aromatic aldehyde compounds are preferable as the
aldehyde compound. Specific compound examples thereof
may include methoxybenzaldehyde, ethoxybenzaldehyde,
propoxybenzaldehyde, butoxybenzaldehyde, veratrum
aldehyde, 2,4-dimethoxybenzaldehyde, 3,5-
dimethoxybenzaldehyde, diethoxybenzaldehyde,
ethoxymethoxybenzaldehyde, trimethoxybenzaldehyde,
heliotropin, and the like. Of these compounds, veratrum
aldehyde and heliotropin are particularly preferable.
The modifier may be used alone or as a mixture of two or
more kinds.
[0108]
Any solvent may be freely used as an organic
solvent used in the modification reaction so long as it
is not reacted with the conjugated diene polymer. The
same solvent as that used in the production of the
conjugated diene polymer is usually used. Specific
examples thereof may include aromatic hydrocarbon
solvents such as benzene, chlorobenzene, toluene, and
44
xylene; aliphatic hydrocarbon solvents having 5 to 10
carbon atoms such as n-heptane, n-hexane, n-pentane, and
n-octane; alicyclic hydrocarbon solvents such as
cyclohexane, methyl cyclohexane, tetralin, and decalin,
and the like. Methylene chloride and tetrahydrofuran may
also be used.
[0109]
The temperature of the reaction solution in the
modification reaction is within a range of preferably 0
to 100C, particularly preferably 30 to 90C. When the
temperature is too low, the modification reaction slowly
proceeds, whereas when the temperature is too high, the
polymer is likely to cause gelation. The time of the
modification reaction is not particularly limited, and it
is within a range of preferably one minute to 5 hours,
more preferably 3 minutes to one hour. When the
modification reaction time is too short, the reaction
proceeds insufficiently, whereas when the time is too
long, the polymer is likely to cause gelation.
[0110]
The amount of the conjugated diene polymer in the
modification reaction solution is within a range of
usually 5 to 500 g per liter of the solvent, preferably
20 to 300 g, further more preferably 30 to 200 g.
[0111]
The amount of the modifier used in the modification
reaction is within a range of usually 0.01 to 150
45
millimoles per 100 g of the conjugated diene polymer,
preferably 0.1 to 100 millimoles, further more preferably
0.2 to 50 millimoles. When the amount used is too small,
the amount of the modified groups introduced into the
modified conjugated diene polymer becomes small, and thus
only a small modifying effect is exhibited. When the
amount used is too large, an unreacted modifier,
undesirably, remains in the modified conjugated diene
polymer and the removal thereof takes labor.
[0112]
The modification reaction is performed by the
following methods: a method in which after the
polymerization reaction, the modifier and then a
polymerization terminator are added thereto, and the
solvent and unreacted monomers remaining the reaction
product are removed in a steam stripping method or a
vacuum drying method; a method in which after the
addition of a polymerization terminator, the modifier is
added thereto; a method in which after the dried polymer
is resolved in a solvent, the modifier and a catalyst are
added thereto, and the like. As some polymerization
terminators may reduce the activity of that site of the
polymer which is reacted with the modifier, depending on
the kind of the polymerization terminator, methods in
which the modifier is added before the polymerization is
stopped are preferable.
[0113]
46
In the present invention, the degree of
modification of the modified conjugated diene polymer is
calculated using a gel permeation chromatography (GPC)
measurement. The method will be explained in detail
using a modified cis-1,4-polybutadiene as an example
referring to Fig. 1.
[0114]
In Fig. 1, a vertical axis shows a value of UV/RI,
a ratio of a peak area UV determined from a UV absorbance
at 274 nm of a polymer, obtained from a GPC measurement,
and a peak area RI obtained from a differential
refractive index (RI).
[0115]
A horizontal axis represents a value of (1/Mn)104,
wherein Mn is a number average molecular weight. In Fig.
1, Li-BR (unmodified ) represents a line obtained by
plotting UV/RI values of a polymer itself obtained by
polymerizing 1,3-butadiene according to a living anionic
polymerization using an Li catalyst, relative to a
polymer having a different number average molecular
weight Mn, which can be approximated to a straight line.
In addition, Li-BR (modified) is a line obtained by
plotting, relative to a polymer having a different number
average molecular weight Mn, UV/RI values of a polymer
obtained by performing a living anionic polymerization
using an Li catalyst, and then modifying the resulting
product by reacting polymerization terminals with a pre47
determined modifier, which can be approximated to a
straight line.
[0116]
In the case of the living anionic polymerization,
since one molecule of a polymer and one molecule of a
modifier are quantitatively reacted with each other, a
difference between a UV/RI value on the Li-BR (modified)
and a UV/RI value on the Li-BR(unmodified ) at a certain
number average molecular weight (Mn 1) is defined as A.
The difference shows a variation in the UV/RI value when
one molecular chain having the number average molecular
weight (Mn 1) is reacted with one molecule of the
modifier, and thus a degree of modification can be
calculated based on the value described above.
[0117]
In the same manner as in the case of the Li-BR,
UV/RI values are calculated respectively for a modified
cis-1,4-polybutadiene having a certain number average
molecular weight (Mn 1) of the present invention, and a
non-modified cis-1,4-polybutadiene obtained by the same
manner as that of the modified polymer above, and a
difference between them is defined as B. The degree of
modification of the modified cis-1,4-polybutadiene of the
present invention is shown by the following formula:
[0118]
[Mathematical Formula 1]
Degree of Modification = B/A
48
[0119]
The degree of modification of the modified
conjugated diene polymer of the present invention is not
particularly limited, and it is preferably more than 0.1,
more preferably more than 0.5, further more preferably
more than 0.7. The degree of modification is also
preferably less than 20, more preferably less than 15,
further preferably less than 10. When the degree of
modification is 0.1 or less, the effects obtained by the
modification may sometimes be insufficient; whereas when
the degree of modification is 20 or more, the original
properties of the conjugated diene polymer may sometimes
be deteriorated. Within a range of a preferable degree
of modification, dispersibility of filler can be improved
in a rubber due to an interaction of polar groups of the
modifier groups (an amino group, an alkoxy group, and the
like) with polar groups of the filler.
[0120]
(Production Method of Vinylcis-Polybutadiene
(VCR))
Further, according to the present invention, there
is provided a method for producing a polybutadiene
including a cis-1,4 polymerization of a 1,3-butadiene,
and then a syndiotactic-1,2 polymerization in the
resulting polymerization system, wherein a catalyst for a
conjugated diene polymerization (the catalyst for a
conjugated diene polymerization of the present invention)
49
including a non-metallocene type gadolinium compound (A)
represented by the following general formula (1), an
ionic compound (B) formed of a non-coordinating anion and
a cation, and an organic metal compound (C) of an element
selected from the group consisting of a group 2, a group
12, and a group 13 of the periodic table is used as a
catalyst for the cis-1,4 polymerization, and a catalyst
system containing a sulfur compound is used as a catalyst
for the syndiotactic-1,2 polymerization, to obtain a
vinylcis-polybutadiene; and further provided a vinylcispolybutadiene
(VCR) obtained according to the method
described above. The inventions will be explained in
detail below.
[0121]
The component (A), the gadolinium compound, of the
cis-1,4 polymerization catalyst system in the present
invention is preferably a non-metallocene type gadolinium
compound represented by the general formula (1) described
above, but other gadolinium compounds may be used so long
as they are soluble in a non-polar organic solvent.
Examples thereof may include gadolinium salts,
halogenated gadolinium, gadolinium alkoxides, nonmetallocene
type gadolinium complexes, and the like.
[0122]
The gadolinium salt described above may include,
for example, gadolinium acetate, gadolinium oxalate,
gadolinium nitrate, gadolinium hydroxide, and the like.
50
[0123]
The halogenated gadolinium described above may
include, for example, gadolinium fluoride, gadolinium
chloride, gadolinium bromide, gadolinium iodide, and the
like.
[0124]
The gadolinium alkoxide described above may include,
for example, trimethoxygadolinium, triethoxygadolinium,
tripropoxygadolinium, triisopropoxygadolinium,
tributoxygadolinium, and the like.
[0125]
As for the cis-1,4 polymerization component in the
vinylcis-polybutadiene obtained in the present invention,
a cis-1,4-polybutadiene having 90% or more, more
preferably 92% or more, particularly preferably 96% or
more, of cis-1,4 structures is preferable. The [] of
the cis-1,4 polymerization component can be controlled to
preferably from 0.1 to 10.0, more preferably from 1.0 to
7.0, particularly preferably from 1.5 to 5.0.
[0126]
Subsequently, using the thus obtained cis-1,4
polymerization reaction mixture as above, the
syndiotactic-1,2 polymerization is performed in this polymerization system. At that time, 1,3-butadiene may
be or may not be newly added thereto. It is preferable
to use a catalyst system containing a sulfur compound as
a catalyst in the syndiotactic-1,2 polymerization.

WE CLAIM:
1. A catalyst for a conjugated diene polymerization
comprising: a non-metallocene type gadolinium compound
(A) represented by the following general formula (1); an
ionic compound (B) including a non-coordinating anion and
a cation; and an organic metal compound (C) of an element
selected from the group consisting of a group 2, a group
12, and a group 13 of the periodic table,
[Chemical Formula 1]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
2. The catalyst for a conjugated diene polymerization
according to claim 1, wherein the organic metal compound
(C) is an organic aluminum compound.
3. The catalyst for a conjugated diene polymerization
according to claim 1 or 2, wherein the ionic compound (B)
is a boron-containing compound.
218
4. A method for producing a conjugated diene polymer
comprising a polymerization of a conjugated diene
compound using the catalyst for a conjugated diene
polymerization according to any one of claims 1 to 3.
5. A method for producing a modified conjugated diene
polymer comprising:
polymerizing a conjugated diene compound using a
catalyst for a conjugated diene polymerization including
a non-metallocene type gadolinium compound (A)
represented by the following general formula (1), an
ionic compound (B) formed of a non-coordinating anion and
a cation, and an organic metal compound (C) of an element
selected from the group consisting of a group 2, a group
12, and a group 13 of the periodic table to obtain a
conjugated diene polymer; and
modifying the conjugated diene polymer with an
amino group-containing carbonyl compound to obtain a
modified conjugated diene polymer,
[Chemical Formula 2]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
219
6. The method for producing a modified conjugated
diene polymer according to claim 5, wherein the amino
group-containing carbonyl compound is a 4,4'-bisdialkylaminobenzophenone.
7. The method for producing a modified conjugated
diene polymer according to claim 5 or 6, wherein the
molecular weight is adjusted with a compound selected
from the group consisting of (1) a hydrogen ,(2) a metal
hydride compound, and (3) a hydrogenated organic metal
compound in the polymerization of the conjugated diene
compound.
8. A method for producing a modified conjugated diene
polymer comprising:
polymerizing a conjugated diene compound using a
catalyst for a conjugated diene polymerization including
a non-metallocene type gadolinium compound (A)
represented by the following general formula (1), an
ionic compound (B) formed of a non-coordinating anion and
a cation, and an organic metal compound (C) of an element
selected from the group consisting of a group 2, a group
12, and a group 13 of the periodic table to obtain a
conjugated diene polymer; and
220
modifying the conjugated diene polymer with a
halogenated benzyl compound to obtain a modified
conjugated diene polymer,
[Chemical Formula 3]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
9. The method for producing a modified conjugated
diene polymer according to claim 8, wherein the
halogenated benzyl compound is a piperonyl chloride, a
dimethoxybenzyl bromide, or a methoxybenzyl chloride.
10. The method for producing a modified conjugated
diene polymer according to claim 8 or 9, wherein the
molecular weight is adjusted with a compound selected
from the group consisting of (1) a hydrogen, (2) a metal
hydride compound, and (3) a hydrogenated organic metal
compound in the polymerization of the conjugated diene
compound.
11. A method for producing a modified conjugated diene
polymer comprising:
221
polymerizing a conjugated diene compound using a
catalyst for a conjugated diene polymerization including
a non-metallocene type gadolinium compound (A)
represented by the following general formula (1), an
ionic compound (B) formed of a non-coordinating anion and
a cation, and an organic metal compound (C) of an element
selected from the group consisting of a group 2, a group
12, and a group 13 of the periodic table to obtain a
conjugated diene polymer; and
modifying the conjugated diene polymer with an
aldehyde compound to obtain a modified conjugated diene
polymer,
[Chemical Formula 4]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
12. The method for producing a modified conjugated
diene polymer according to claim 11, wherein the aldehyde
compound is a heliotropin or a veratrum aldehyde.
13. The method for producing a modified conjugated
diene polymer according to claim 11 or 12, wherein the
222
molecular weight is adjusted with a compound selected
from (1) a hydrogen,(2) a metal hydride compound, and
(3)a hydrogenated organic metal compound in the
polymerization of the conjugated diene compound.
14. A method for producing a vinylcis-polybutadiene
comprising performing a cis-1,4 polymerization of a 1,3-
butadiene, and performing a subsequent syndiotactic-1,2
polymerization in the resulting polymerization system,
wherein a catalyst for a conjugated diene
polymerization including a non-metallocene type
gadolinium compound (A) represented by the following
general formula (1), an ionic compound (B) formed of a
non-coordinating anion and a cation, and an organic metal
compound (C) of an element selected from the group
consisting of a group 2, a group 12, and a group 13 of
the periodic table is used as a catalyst in the cis-1,4
polymerization, and a catalyst system containing a sulfur
compound is used as a catalyst in the syndiotactic-1,2
polymerization,
[Chemical Formula 5]
223
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
15. The method for producing a vinylcis-polybutadiene
according to claim 14, wherein the organic metal compound
(C) is an organic aluminum compound.
16. The method for producing a vinylcis-polybutadiene
according to claim 14 or 15, wherein the ionic compound
(B) is a boron-containing compound.
17. The method for producing a vinylcis-polybutadiene
according to any one of claims 14 to 16, wherein a
catalyst system including a cobalt compound, a trialkyl
aluminum compound, and a sulfur compound is used as the
catalyst in the syndiotactic-1,2 polymerization.
18. A vinylcis-polybutadiene obtained by a production
method comprising:
performing a cis-1,4 polymerization of a 1,3-
butadiene using a catalyst for a conjugated diene
polymerization including a non-metallocene type
gadolinium compound (A) represented by the following
general formula (1), an ionic compound (B) formed of a
non-coordinating anion and a cation, and an organic metal
compound (C) of an element selected from the group
224
consisting of a group 2, a group 12, and a group 13 of
the periodic table; and
performing a syndiotactic-1,2 polymerization using
a catalyst system containing a sulfur compound in the
resulting polymerization system,
[Chemical Formula 6]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
19. A conjugated diene polymer composition comprising:
a conjugated diene polymer () resulting from a
polymerization of a conjugated diene compound using a
catalyst for a conjugated diene polymerization including
a non-metallocene type gadolinium compound (A)
represented by the following general formula (1), an
ionic compound (B) formed of a non-coordinating anion and
a cation, and an organic metal compound (C) of an element
selected from the group consisting of a group 2, a group
12, and a group 13 of the periodic table;
a diene polymer () other than the (); and
a rubber-reinforcing agent (),
[Chemical Formula 7]
225
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
20. The conjugated diene polymer composition according
to claim 19, wherein the rubber-reinforcing agent () is
a carbon black.
21. The conjugated diene polymer composition according
to claim 19 or 20, wherein the molecular weight of the
conjugated diene compound is adjusted with a compound
selected from the group consisting of (1) a hydrogen, (2)
a metal hydride compound, (3) a hydrogenated organic
metal compound.
22. The conjugated diene polymer composition according
to any one of claims 19 to 21, wherein the conjugated
diene compound is a 1,3-butadiene.
23. A modified conjugated diene polymer composition
comprising:
a modified conjugated diene polymer (’) obtained
by polymerizing a conjugated diene compound using a
226
catalyst for a conjugated diene polymerization including
a non-metallocene type gadolinium compound (A)
represented by the following general formula (1), a ionic
compound (B) formed of a non-coordinating anion and a
cation, and an organic metal compound (C) of an element
selected from the group consisting of a group 2, a group
12, and a group 13 of the periodic table, and then
modifying the resulting polymer with an amino groupcontaining
carbonyl compound;
a diene polymer () other than the ('); and a
rubber-reinforcing agent (),
[Chemical Formula 8]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
24. The modified conjugated diene polymer composition
according to claim 23, wherein the rubber-reinforcing
agent () is a carbon black.
25. The modified conjugated diene polymer composition
according to claim 23 or 24, wherein the amino group227
containing carbonyl compound is a 4,4’-bisdialkylaminobenzophenone.
26. The modified conjugated diene polymer composition
according to any one of claims 23 to 25, wherein the
molecular weight of the conjugated diene compound is
adjusted with a compound selected from the group
consisting of (1) a hydrogen, (2) a metal hydride
compound, and (3) a hydrogenated organic metal compound.
27. The modified conjugated diene polymer composition
according to any one of claims 23 to 26, wherein the
conjugated diene compound is a 1,3-butadiene.
28. A rubber composition for a tire comprising:
rubber components () + () which are formed of a
conjugated diene polymer () obtained by polymerizing a
conjugated diene compound using a catalyst for a
conjugated diene polymerization including a nonmetallocene
type gadolinium compound (A) represented by
the following general formula (1), an ionic compound (B)
formed of a non-coordinating anion and a cation, and an
organic metal compound (C) of an element selected from
the group consisting of a group 2, a group 12, and a
group 13 of the periodic table, and a diene polymer ()
other than the (); and
a rubber-reinforcing agent (),
228
wherein the rubber-reinforcing agent () is
included in an amount of 30 to 80 parts by mass based on
100 parts by mass of the rubber components () + (),
[Chemical Formula 9]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
29. A rubber composition for a tire comprising:
rubber components (') + () which are formed of a
modified conjugated diene polymer (') obtained by
polymerizing a conjugated diene compound using a catalyst
for a conjugated diene polymerization including a nonmetallocene
type gadolinium compound (A) represented by
the following general formula (1), an ionic compound (B)
formed of a non-coordinating anion and a cation, and an
organic metal compound (C) of an element selected from
the group consisting of a group 2, a group 12, and a
group 13 of the periodic table, and then modifying the
resulting polymer, and a diene polymer () other than the
('); and
a rubber-reinforcing agent (),
229
wherein the rubber-reinforcing agent () is
included in an amount of 30 to 80 parts by mass based on
100 parts by mass of the rubber components (') + (),
[Chemical Formula 10]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
30. The rubber composition for a tire according to
claim 28 or 29, wherein the diene polymer () is a
natural rubber and/or a polyisoprene.
31. The rubber composition for a tire according to any
one of claims 28 to 30, wherein the rubber-reinforcing
agent () is a carbon black.
32. A tire comprising the rubber composition for a tire
according to any one of claims 28 to 31 as a rubber
substrate.
33. A rubber composition for a rubber belt comprising:
rubber components () + () which are formed of a
conjugated diene polymer () obtained by polymerizing a
230
conjugated diene compound using a catalyst for a
conjugated diene polymerization including a nonmetallocene
type gadolinium compound (A) represented by
the following general formula (1), an ionic compound (B)
formed of a non-coordinating anion and a cation, and an
organic metal compound (C) of an element selected from
the group consisting of a group 2, a group 12, and a
group 13 of the periodic table, and a diene polymer ()
other than the (); and
a rubber-reinforcing agent (),
wherein the rubber-reinforcing agent () is
included in an amount of 20 to 70 parts by mass based on
100 parts by mass of the rubber components () + (),
[Chemical Formula 11]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
34. A rubber composition for a rubber belt comprising:
rubber components (') + () which are formed of a
modified conjugated diene polymer (') obtained by
polymerizing a conjugated diene compound using a catalyst
for a conjugated diene polymerization including a non231
metallocene type gadolinium compound (A) represented by
the following general formula (1), an ionic compound (B)
formed of a non-coordinating anion and a cation, and an
organic metal compound (C) of an element selected from
the group consisting of a group 2, a group 12, and a
group 13 of the periodic table, and then modifying the
resulting polymer, and a diene polymer () other than the
('); and
a rubber-reinforcing agent (),
wherein the rubber-reinforcing agent () is
included in an amount of 20 to 70 parts by mass based on
100 parts by mass of the rubber components (') + (),
[Chemical Formula 12]
wherein R1, R2, and R3 each shows a hydrogen or a
substituent having 1 to 12 carbon atoms, O shows an
oxygen atom, and Gd shows a gadolinium atom.
35. The rubber composition for a rubber belt according
to claim 33 or 34, wherein the rubber-reinforcing agent
() is a carbon black and/or a silica.
36. The rubber composition for a rubber belt according
to any one of claims 33 to 35, wherein a carbon black and
232
a silica are used as the rubber-reinforcing agent (),
and the silica is included in an amount of 70% by mass of
less in the rubber-reinforcing agent.
37. A rubber belt comprising the rubber composition for
a rubber belt according to any one of claims 33 to 36 as
a rubber