JP7240787B2 - Conjugated diene-based graft polymer and method for producing the same - Google Patents

Description

TECHNICAL FIELD The present invention relates to a conjugated diene-based graft polymer having excellent affinity with polar materials and high stability, and a method for producing the same.

Conventionally, it has been known that branched polymers have higher fluidity than linear polymers of the same molecular weight, and have an excellent balance between workability and mechanical properties. For example, a method of forming a conjugated diene-based graft polymer by reacting a polybutadiene grafted with a silyl chloride group by hydrosilylation and a living polymer having an active terminal for living anionic polymerization is known (see Non-Patent Document 1). ). Further, it is known that a conjugated diene-based star polymer in which one or more alkoxy groups and/or hydroxyl groups are bonded on average per silicon atom has excellent silica dispersibility (see Patent Document 1). .

WO2018/034195

Macromolecules, 1997, 30, 5602

However, the conjugated diene-based graft polymer described in Non-Patent Document 1 does not have an alkoxysilyl group or a silanol group that has an affinity with polar materials, so the affinity with polar materials such as glass and silica is improved. There was room for In addition, the conjugated diene star polymer described in Patent Document 1 has a problem that the stability of the polymer is low because the total content of alkoxysilyl groups and silanol groups capable of undergoing a condensation reaction is large.

The present invention has been made in view of the above circumstances, and provides a conjugated diene-based graft polymer having excellent affinity with polar materials and high stability, and a method for producing the conjugated diene-based graft polymer. intended to provide

As a result of intensive studies by the present inventors, at least one monomer selected from the group consisting of a conjugated diene unit and an aromatic vinyl compound unit via a branch point in the main chain composed of a polymer containing a conjugated diene unit A conjugated diene-based graft polymer in which a side chain composed of a polymer containing a polymer unit is bonded directly or through a linking chain, wherein the number of at least one group selected from the group consisting of alkoxy groups and hydroxyl groups bonded to the branch point is within a certain range, the conjugated diene-based graft polymer has excellent affinity with polar materials and has high stability, leading to the completion of the present invention.

That is, the present invention provides the following [1] to [11].
[1] In the main chain (a) made of a polymer containing a conjugated diene unit,
A side chain (b ) is a conjugated diene-based graft polymer in which
the main chain (a) is directly or through a linking chain bound to the branch point,
The side chain (b) is directly attached to the branch point,
the heteroatom is at least one selected from the group consisting of Si, Sn, Ge, Pb, P, B, and Al;
At least one of the branch points is directly bonded to at least one functional group (c) selected from the group consisting of an alkoxy group and a hydroxyl group,
The average number X of the functional groups (c) directly bonded to the branch points per molecule of the conjugated diene-based graft polymer and the average number Y of the branch points per molecule of the conjugated diene-based graft polymer are represented by the following formula (2);
0<(X/Y)<1 (2)
satisfy the relationship of
Conjugated diene graft polymer.
[2] The average number X of the functional groups (c) directly bonded to the branch points per molecule of the conjugated diene-based graft polymer is represented by the following formula (3);
0<X≦10 (3)
The conjugated diene-based graft polymer according to [1], which satisfies the relationship:
[3] The conjugated diene-based graft polymer according to [1] or [2], wherein the heteroatom is Si.
[4] The average number W of side chains (b) directly bonded to the branch points per molecule of the conjugated diene-based graft polymer and the average number Y of branch points per molecule of the conjugated diene-based graft polymer are calculated by the following formula ( 4);
0.5≦(W/Y) (4)
The conjugated diene-based graft polymer according to any one of [1] to [3], which satisfies the relationship of

[5] (A-1) An active terminal polymer represented by the following formula (I) (hereinafter, this polymer is referred to as an active terminal polymer (I)) and PX (I)
(In formula (I), P represents a polymer chain containing at least one monomer unit selected from the group consisting of conjugated diene units and aromatic vinyl compound units, and X represents an anionic polymerization active terminal),
a functional group-modified conjugated diene-based polymer having as a branched chain a moiety containing a functional group represented by the following formula (II) (hereinafter, this polymer is referred to as a functional group-modified conjugated diene-based polymer (F)); Step of reacting to produce a conjugated diene-based graft polymer

（式（ＩＩ）中、Ｖは、アルコキシ基または水酸基を示し、ＺはＳｉ、Ｓｎ、Ｇｅ、Ｐｂ、Ｐ、Ｂ、またはＡｌであり、Ｒ¹は炭素数６～１２のアリール基、炭素数１～１２のアルキル基、または水素原子を示し、Ｎは前記Ｚの価数を示し、ｎは下記式（５）を満たす整数であり
１≦ｎ≦Ｎ－１ （５）
ｎが２以上の場合、Ｖは同一でも異なっていてもよく、Ｎ－ｎが２以上の場合、Ｒ¹は同一でも異なっていてもよく、分岐鎖が主鎖に対し、複数含まれる場合には、Ｚは同一でも異なっていてもよい。）；および
（Ｂ）得られた共役ジエン系グラフト重合体を回収する工程；
を含む、［１］に記載の共役ジエン系グラフト重合体の製造方法。
［６］さらに、工程（Ｂ）の前において、
（Ａ－２）前記共役ジエン系グラフト重合体中のアルコキシ基および水酸基からなる群より選ばれる少なくとも１つの残存する官能基の一部を不活性化する工程；
を含む、［５］に記載の共役ジエン系グラフト重合体の製造方法。
［７］前記式（ＩＩ）中のＺがＳｉである、［５］または［６］に記載の共役ジエン系グラフト重合体の製造方法。
［８］前記式（ＩＩ）中の官能基Ｖがアルコキシ基である、［５］～［７］のいずれかに記載の共役ジエン系グラフト重合体の製造方法。
［９］［５］～［８］のいずれか１項に記載の製造方法により得られる、［１］～［４］のいずれかに記載の共役ジエン系グラフト重合体。
［１０］［１］～［４］および［９］のいずれかに記載の共役ジエン系グラフト重合体を含有する、重合体組成物。
［１１］［１０］に記載の重合体組成物を成形してなる成形品。

(In formula (II), V represents an alkoxy group or a hydroxyl group, Z is Si, Sn, Ge, Pb, P, B, or Al, R ¹ is an aryl group having 6 to 12 carbon atoms, 1 to 12 alkyl groups or hydrogen atoms, N represents the valence of Z, n is an integer satisfying the following formula (5) and 1 ≤ n ≤ N-1 (5)
When n is 2 or more, V may be the same or different; when Nn is 2 or more, R ¹ may be the same or different; , Z may be the same or different. ); and (B) a step of recovering the obtained conjugated diene-based graft polymer;
The method for producing a conjugated diene-based graft polymer according to [1], comprising:
[6] Furthermore, before step (B),
(A-2) a step of partially inactivating at least one remaining functional group selected from the group consisting of alkoxy groups and hydroxyl groups in the conjugated diene-based graft polymer;
The method for producing a conjugated diene-based graft polymer according to [5].
[7] The method for producing a conjugated diene-based graft polymer according to [5] or [6], wherein Z in the formula (II) is Si.
[8] The method for producing a conjugated diene-based graft polymer according to any one of [5] to [7], wherein the functional group V in formula (II) is an alkoxy group.
[9] The conjugated diene-based graft polymer according to any one of [1] to [4], which is obtained by the production method according to any one of [5] to [8].
[10] A polymer composition containing the conjugated diene-based graft polymer according to any one of [1] to [4] and [9].
[11] A molded article obtained by molding the polymer composition according to [10].

ADVANTAGE OF THE INVENTION According to this invention, while being excellent in affinity with a polar material, the conjugated diene system graft polymer which has high stability, and its manufacturing method are provided.

The present invention will be described in detail below.
The conjugated diene-based graft polymer of the present invention is
In the main chain (a) made of a polymer containing a conjugated diene unit,
A side chain (b ) is a conjugated diene-based graft polymer in which
the main chain (a) is directly or through a linking chain bound to the branch point,
The side chain (b) is directly attached to the branch point,
the heteroatom is at least one selected from the group consisting of Si, Sn, Ge, Pb, P, B, and Al;
At least one of the branch points is directly bonded to at least one functional group (c) selected from the group consisting of an alkoxy group and a hydroxyl group,
The average number X of the functional groups (c) directly bonded to the branch points per molecule of the conjugated diene-based graft polymer and the average number Y of the branch points per molecule of the conjugated diene-based graft polymer are represented by the following formula (2);
0<(X/Y)<1 (2)
satisfy the relationship
In the present invention, the term "graft polymer" refers to a polymer having a backbone composed of a polymer chain and side chains composed of a polymer chain as branches. The body unit and the monomer unit that constitutes the side chain polymer chain may be the same or different.

<Main chain (a)>
The conjugated diene-based graft polymer of the present invention has a main chain (a) composed of a polymer containing conjugated diene units. The main chain contained in the conjugated diene-based graft polymer of the present invention refers to the entire portion derived from all monomer units including the conjugated diene units constituting the main chain. For example, when producing a conjugated diene-based graft polymer by the production method of the present invention, an unmodified conjugated diene-based polymer that is a precursor of the functional group-modified conjugated diene-based polymer (F) used in the production It refers to the entire portion derived from (F'). _For example, when the unmodified conjugated diene-based polymer (F′) contains vinyl-bonded butadiene units, the —CH= The main chain includes up to the CH ₂ portion (the portion that becomes —CH—CH ₂ — when a modifying compound is added).

Main chain (a) has, in its polymer chain skeleton, units other than vinyl monomer units derived from vinyl monomers such as conjugated dienes and aromatic vinyl compounds (e.g., units derived from residues of coupling agents units having Si atoms or N atoms). When a unit other than the vinyl monomer unit is contained in the main chain skeleton, the main chain skeleton is cleaved under conditions such that the bond between the heteroatom and the carbon, which is the branch point described later, is cut, or under shearing or heat. Therefore, the physical properties tend to deteriorate. In addition, the terminal of the polymer chain, which is the main chain, may have a group other than the monomer unit.

The main chain (a) contains conjugated diene units as monomer units constituting the polymer. Examples of conjugated dienes 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, farnesene, and conjugated dienes other than butadiene and isoprene such as chloroprene. Among these conjugated dienes, butadiene and isoprene are preferred, and butadiene is more preferred. The conjugated diene to be the conjugated diene unit may be used alone or in combination of two or more.

In one embodiment, the main chain (a) preferably contains at least one monomer unit selected from the group consisting of butadiene and isoprene in at least 50% by mass of the total monomer units constituting the polymer. be. The total content of butadiene units and isoprene units is preferably 60 to 100% by mass, more preferably 70 to 100% by mass, based on the total monomer units of the main chain (a).

Examples of monomer units other than butadiene units and isoprene units that can be contained in the main chain (a) include conjugated diene units other than butadiene and isoprene units described above, aromatic vinyl compound units, and the like.

Examples of aromatic vinyl compounds include styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-propylstyrene, 4-t-butylstyrene, 4-cyclohexylstyrene, 4- Dodecylstyrene, 2,4-dimethylstyrene, 2,4-diisopropylstyrene, 2,4,6-trimethylstyrene, 2-ethyl-4-benzylstyrene, 4-(phenylbutyl)styrene, 1-vinylnaphthalene, 2- vinylnaphthalene, vinylanthracene, N,N-diethyl-4-aminoethylstyrene, vinylpyridine, 4-methoxystyrene, monochlorostyrene, dichlorostyrene, divinylbenzene and the like. Among these aromatic vinyl compounds, styrene, α-methylstyrene, and 4-methylstyrene are preferred. The aromatic vinyl compound to be the aromatic vinyl compound unit may be used alone or in combination of two or more.

The content of monomer units other than butadiene units and isoprene units in the main chain (a) is preferably 50% by mass or less, more preferably 40% by mass or less, and even more preferably 30% by mass or less. . For example, when the aromatic vinyl compound unit is less than the above range, the resulting conjugated diene-based graft polymer tends to be improved in processability. Further, when a conjugated diene-based graft polymer is produced by the production method of the present invention, the reactivity tends to be improved when the unmodified conjugated diene-based polymer (F') is modified with a functional group.

In one embodiment, the weight average molecular weight (Mw) of the main chain (a) is preferably 1,000 or more and 1,000,000 or less, more preferably 2,000 or more and 500,000 or less, and 3,000 or more and 100 ,000 or less is more preferable. In the present invention, the Mw of the main chain (a) is, for example, in the case of producing a conjugated diene-based graft polymer by the production method of the present invention, the functional group-modified conjugated diene-based polymer that becomes a constituent of the main chain described later. (F), or Mw of the unmodified conjugated diene-based polymer (F'). When the Mw of the main chain (a) is within the above range, there is a tendency for excellent processability during production and favorable economic efficiency. In the present invention, unless otherwise specified, Mw is a weight average molecular weight in terms of standard polystyrene obtained from measurement by gel permeation chromatography (GPC).

Although the vinyl content of the main chain (a) is not particularly limited, it is preferably 90 mol% or less, more preferably 80 mol% or less, and even more preferably 70 mol% or less. The vinyl content of the main chain (a) is preferably 0.5 mol % or more, more preferably 1 mol % or more. In the present invention, the "vinyl content" refers to 1,2-bonds, 3,4-bonds (other than farnesene), and 3,13- of conjugated diene units (conjugated diene units other than 1,4-bonds (other than farnesene) and 1,13-bonds (for farnesene)) means total mol %. Vinyl content is derived from conjugated diene units linked by 1,2-linkages, 3,4-linkages (for non-farnesene), and 3,13-linkages (for farnesene) using ¹ H-NMR. is calculated from the area ratio of the peak derived from the 1,4-bond (other than farnesene) and 1,13-bond (farnesene) conjugated diene unit.

The vinyl content of the main chain (a) can be designed according to the purpose. As a result, the obtained conjugated diene-based graft polymer tends to be excellent in fluidity and low-temperature properties. Moreover, when it is 50 mol % or more, the resulting conjugated diene-based graft polymer tends to have excellent reactivity.

When the conjugated diene-based graft polymer is produced by the production method of the present invention, the vinyl content of the main chain (a) is, for example, the unmodified conjugated diene-based polymer that is a constituent of the main chain (a). A desired value can be obtained by controlling the type of solvent used in the production of (F′), the polar compound used as necessary, the polymerization temperature, and the like.

The glass transition temperature (Tg) of the main chain (a) is derived from the butadiene unit, the isoprene unit and the butadiene unit, the vinyl content of the conjugated diene unit other than the isoprene unit, the type of the conjugated diene unit, and the monomer other than the conjugated diene. Although it may vary depending on the content of the units, -150 to 50°C is preferred, -130 to 50°C is more preferred, and -130 to 30°C is even more preferred. When the Tg is within the above range, for example, it is possible to prevent the viscosity from becoming high, which facilitates handling. In the present invention, Tg is the peak top value of DDSC obtained by differential scanning calorimetry (DSC) measurement.

<Side chain (b)>
The conjugated diene-based graft polymer of the present invention has a side chain (b) comprising a polymer containing at least one monomer unit selected from the group consisting of conjugated diene units and aromatic vinyl compound units.

The side chain (b) contains at least one monomer unit selected from the group consisting of conjugated diene units and aromatic vinyl compound units as monomer units constituting the polymer.

Specific examples of the conjugated diene that can constitute the monomer unit of the side chain (b) are the same as the specific examples of the conjugated diene that constitutes the monomer unit of the main chain (a). Butadiene and isoprene are preferred among the conjugated dienes that serve as the conjugated diene unit contained in the side chain (b). The conjugated diene to be the conjugated diene unit may be used alone or in combination of two or more.

Specific examples of the aromatic vinyl compound that can constitute the monomer units of the side chain (b) are the same as the specific examples of the aromatic vinyl compound that can constitute the monomer units of the main chain (a). Among these aromatic vinyl compounds, styrene, α-methylstyrene, and 4-methylstyrene are preferred. The aromatic vinyl compound to be the aromatic vinyl compound unit may be used alone or in combination of two or more.

The side chain (b) is selected from the group consisting of homopolymers, conjugated diene units, and aromatic vinyl compound units, in which the backbone of the polymer chain consists of only one type of conjugated diene unit or one type of aromatic vinyl compound unit. A copolymer consisting of at least one type of monomer unit, or one or more types of monomer units selected from the group consisting of conjugated diene units and aromatic vinyl compound units and vinyl units other than conjugated dienes and aromatic vinyl compounds. It may be a copolymer with a monomer unit of a polymer. Moreover, the polymer constituting the side chain (b) may be of one type alone, or may be of two or more types having different structures.

The ratio of the conjugated diene unit that can constitute the side chain (b) is not particularly limited, and can be designed according to the purpose. is more preferable, particularly preferably 70% by mass or more, and may be 100% by mass. When the ratio of the conjugated diene units is 50% by mass or more, the processability of the obtained conjugated diene-based graft polymer tends to be improved.

The ratio of the aromatic vinyl compound unit that can constitute the side chain (b) is not particularly limited, and can be designed according to the purpose. It is more preferably 70% by mass or more, and may be 100% by mass. When the ratio of the aromatic vinyl compound unit is 50% by mass or more, the resulting conjugated diene-based graft polymer tends to have improved mechanical properties.

The side chain (b) contains units other than vinyl monomer units derived from vinyl monomers such as conjugated dienes and aromatic vinyl compounds in the polymer chain skeleton (e.g., units derived from residues of coupling agents units having Si atoms or N atoms). When a unit other than the vinyl monomer is contained in the polymer chain skeleton of the side chain (b), under conditions such that the bond between the heteroatom and the carbon, which is the branch point described later, is cut, or under conditions such as shearing or heat Since the polymer chain skeleton of the side chain (b) is cleaved by the reaction, the physical properties tend to deteriorate. In addition, the terminal of the polymer chain to be the side chain may have a group other than the monomer unit.

In one embodiment, the weight average molecular weight (Mw) of the side chain (b) is preferably 1,000 or more and 1,00,000 or less, more preferably 2,000 or more and 80,000 or less, and 3,000 or more and 50 ,000 or less is more preferable. In the present invention, the Mw of the side chain (b) is, for example, when the conjugated diene-based graft polymer is produced by the production method of the present invention, the active terminal polymer (I) which becomes a component of the side chain described later. is Mw. When the Mw of the side chain (b) is within the above range, there is a tendency that the process passability during production is excellent and the economy is favorable.

Although the vinyl content of the side chain (b) is not particularly limited, it is preferably 90 mol% or less, more preferably 80 mol% or less, and even more preferably 70 mol% or less. The vinyl content of the side chain (b) is preferably 0.5 mol % or more, more preferably 1 mol % or more. The vinyl content of the side chain (b) is, for example, when the conjugated diene-based graft polymer is produced by the production method of the present invention, the ¹ H - Calculated in the same manner as for the main chain (a) from the NMR spectrum.

The vinyl content of the side chain (b) can be designed according to the purpose. As a result, the obtained conjugated diene-based graft polymer tends to be excellent in fluidity and low-temperature properties. Moreover, when it is 50 mol % or more, the resulting conjugated diene-based graft polymer tends to have excellent reactivity.

When the conjugated diene-based graft polymer is produced by the production method of the present invention, the vinyl content of the side chain (b) is, for example, the active terminal polymer (I) which is a constituent of the side chain (b). A desired value can be obtained by controlling the type of solvent used in the production of, the polar compound used as necessary, the polymerization temperature, and the like.

The glass transition temperature (Tg) of the side chain (b) may vary depending on the vinyl content of the conjugated diene unit, the type of conjugated diene unit, the content of units derived from monomers other than the conjugated diene, etc. 50°C is preferred, -130 to 50°C is more preferred, and -130 to 30°C is even more preferred. When the Tg is within the above range, for example, it is possible to prevent the viscosity from increasing, which facilitates handling.

<Conjugated diene-based graft polymer>
In the conjugated diene-based graft polymer of the present invention, the side chain (b) is bonded to the main chain (a) via one heteroatom having a valence of 3 or more, which is a branch point, and the branch point is a conjugated diene-based graft polymer in which at least one functional group (c) selected from the group consisting of an alkoxy group and a hydroxyl group is bonded to at least one of the

The main chain (a) is directly or through a connecting chain attached to the branch point, the side chain (b) is attached directly to the branch point, and the functional group (c) is attached directly to the branch point. Here, the term "directly bound to a branch point" means that the branch point is directly bound to a portion derived from a monomer unit constituting the main chain. The branch point and bond through the linking chain means that one end of the linking chain is attached to the part derived from the monomer unit constituting the main chain, and the branching point is directly attached to the other end of the linking chain. means that For example, when a branch point is bonded to a 1,2-bonded butadiene unit, the case represented by the following formula (III-1) is the case where the branch point is directly bonded to the main chain, and the following formula ( The case shown in III-2) is the case where the branch point is connected to the main chain through a linking chain.

In formulas (III-1) and (III-2) above, Z ⁰ is a heteroatom serving as a branch point, and R ^2a is a linking chain. R ^2a is a divalent organic group, preferably an alkylene group optionally having a heteroatom.

When the branched portion from the main chain including the bonding form of the main chain (a) and the branch point is represented by a chemical formula, a form in which the branch point is directly bonded to the main chain (a) as shown in the following formula (III-3) and a branched portion including a form that is linked to a branch point through a linking chain as in the following formula (III-4). Among these branched moieties, a branched structure including a form that is linked to a branch point through a linking chain as in formula (III-4) is desirable.

In the above formulas (III-3) and (III-4), the wavy portion is the main chain (a), V is the functional group (c), Z ¹ is the branch point, P is the side chain (b), and R ^2b is the linking is a chain.

In formulas (III-3) and (III-4), V represents an alkoxy group or a hydroxyl group, Z ¹ is Si, Sn, Ge, Pb, P, B, or Al, and R ^2b has a heteroatom. is an alkylene group having 1 to 12 carbon atoms, R ³ is an aryl group having 6 to 12 carbon atoms, an alkyl group having 1 to 12 carbon atoms, or a hydrogen atom; P is a conjugated diene unit and an aromatic A polymer chain containing at least one monomer unit selected from the group consisting of group vinyl compound units. N represents the valence of Z, m and n are each independently an integer satisfying the following formula (6);
0≤m≤N-1, 0≤n≤N-1 (6)
When m is 2 or more, P may be the same or different, when n is 2 or more, V may be the same or different, and when Nmn is 2 or more, R ³ may be the same They may be different, and when multiple branch points are included in the main chain, Z ¹ may be the same or different. However, the conjugated diene-based graft polymer of the present invention must contain V (functional group (c)) and P (side chain (b)) while satisfying the relationship of formula (2) above. In addition, in the conjugated diene-based graft polymer of the present invention, since it is sufficient if there is one or more side chains per main chain, Z ¹ (Z ¹ where m is 0) to which no side chain is bonded can be included, still defining Z ¹ as the branch point.

The branch point consists of one heteroatom, and the heteroatom is a heteroatom with a valence of 3 or more. The heteroatom with a valence of 3 or more serving as a branch point is at least one selected from the group consisting of Si, Sn, Ge, Pb, P, B, and Al. Among these heteroatoms, Si and Sn are preferred, and Si is more preferred.

The functional group (c) that becomes the group V is at least one selected from the group consisting of an alkoxy group and a hydroxyl group. Examples of alkoxy groups include methoxy, ethoxy, and propoxy groups. Among the above functional groups (c), a methoxy group, an ethoxy group, and a hydroxyl group are preferred from the viewpoint of affinity with polar materials. The functional group (c) may be a single group or a plurality of groups of two or more types.

R ³ in the above formulas (III-3) and (III-4) represents an aryl group having 6 to 12 carbon atoms, an alkyl group having 1 to 12 carbon atoms, or a hydrogen atom. Among these R ³ , alkyl groups having 1 to 6 carbon atoms are preferred, and n-butyl, sec-butyl, n-propyl, isopropyl, ethyl and methyl groups are more preferred. R ³ may be a single group or a plurality of groups of two or more types.

The alkylene group having 1 to 12 carbon atoms and having a heteroatom which can be R ^2b is preferably an alkylene group having 1 to 12 carbon atoms and having S, and SR ^2b' (R ^2b' is an alkylene group having 1 to 12 carbon atoms. ) is more preferred.

In the conjugated diene-based graft polymer of the present invention, when focusing on the heteroatom that is the branch point contained in the graft polymer, the valence number of the heteroatom is N, and the side directly bonded to one branch point When the average number of chains (b) is B and the average number of functional groups (c) bonded to one branch point is C, the relationship of the following formula (1) is satisfied. By satisfying this condition, the branch point is bonded to the main chain (a) directly or through a connecting chain, and the conjugated diene-based graft polymer of the present invention contains at least the side chain (b) and the functional group (c). will be included.
N-1≧B+C, B>0, C>0 (1)

In the conjugated diene-based graft polymer of the present invention, the average number X of the functional groups (c) directly bonded to the branch points per molecule of the conjugated diene-based graft polymer and the branch points per molecule of the conjugated diene-based graft polymer satisfies the relationship of the following formula (2).
0<(X/Y)<1 (2)
When the (X/Y) is 0, the conjugated diene graft polymer tends to have poor affinity with the polar material, and when the (X/Y) is 1 or more, the conjugated diene graft polymer stability tends to decrease.

From the viewpoint of better affinity and stability with polar materials, the above (X/Y) is preferably in the range of 0.01 or more and 0.99 or less, and is in the range of 0.01 or more and 0.9 or less. is more preferable, and a range of 0.01 or more and 0.5 or less is particularly preferable. In the present invention, (X/Y) (the average number of functional groups (c) per branch point contained in the conjugated diene graft polymer) is, for example, when Z is Si, the conjugated diene graft polymer Determined from the results of ²⁹ Si-NMR measurement of the polymer. Specifically, the integrated values of Si bonded with one functional group (c), Si bonded with two functional groups (c), and the like multiplied by the number of functional groups are summed, and the integral Calculated by comparing with a simple sum of the values. When Z is a heteroatom other than Si, the average number of heteroatoms per molecule of the conjugated diene graft polymer can be similarly determined.

In addition, the average number Y of branch points per molecule of the conjugated diene-based graft polymer is determined by a specific heteroatom (Si, Sn , Ge, Pb, P, B, and Al) content (% by mass) and the number average molecular weight (Mn) in terms of standard polystyrene are used to calculate the molecular weight according to the following formula (8).
(Average number Y of branch points per molecule of conjugated diene-based graft polymer) = [(heteroatom content (% by mass))/100] x [(number average molecular weight Mn)/(molecular weight of styrene unit) x ( average molecular weight of the conjugated diene and optionally other monomeric units other than the conjugated diene)]/(atomic weight of the heteroatom) (8)

In the conjugated diene-based graft polymer of the present invention, the average number X of the functional groups (c) directly bonded to the branch points per molecule of the conjugated diene-based graft polymer satisfies the relationship of the following formula (3). preferable.
0<X≦10 (3)
The average number X of functional groups (c) is calculated by a method described later. When X is 0, the conjugated diene-based graft polymer tends to have poor affinity with polar materials, and when X exceeds 10, the stability of the conjugated diene-based graft polymer tends to decrease. .

From the viewpoint of better compatibility with polar materials and better stability, X is preferably in the range of 0.01 to 9.9, more preferably in the range of 0.02 to 9, and 0.01 to 9.9. A range of 05 or more and 5 or less is particularly preferable. In the present invention, the average number X of the functional groups (c) directly bonded to the branch points per molecule of the conjugated diene graft polymer is the functional group per branch point contained in the conjugated diene graft polymer. It is determined using the average number (X/Y) of (c) and the average number Y of branch points per molecule of the conjugated diene graft polymer.

The number of side chains (b) and the number of functional groups (c) that are directly bonded to the branch point are determined, for example, in the steps described later when the conjugated diene-based graft polymer is produced by the production method of the present invention. From the molar ratio of the amount of active terminal polymer (I) and functional group-modified conjugated diene polymer (F) charged in (A-1) and the group consisting of alkoxy groups and hydroxyl groups in step (A-2) described later The amount and reaction time of the reagent used to inactivate at least one selected remaining functional group (functional group V present unreacted), and the amount of polar compound used as necessary It can be adjusted within a desired range depending on the type and amount added.

The stability of the conjugated diene-based graft polymer can be evaluated, for example, by the change in appearance and the formation of insoluble matter (gelled matter) during long-term storage under normal temperature and normal pressure. Alternatively, the conjugated diene-based graft polymer can be heated and depressurized to promote the condensation reaction of the alkoxysilyl group or silanol group.

The affinity with a polar material can be measured, for example, by applying a conjugated diene-based graft polymer or a conjugated diene-based graft polymer composition on a glass substrate and heating for a certain period of time to cure the composition, and then measuring the peel strength. It can be evaluated by conducting a cross-cut test or the like. Also, the condensation reactivity of the alkoxysilyl group or the silanol group can be used to evaluate the reactivity and affinity with polar materials such as glass and silica. When a solution containing a conjugated diene-based graft polymer is shaken under acidic or basic conditions, if the condensation reactivity is high, an insoluble matter (gel material) is generated. Reactivity with materials can be evaluated.

In the conjugated diene-based graft polymer of the present invention, the average number of side chains (b) directly bonded to the branch points per molecule of the conjugated diene-based graft polymer is W, and the branch per molecule of the conjugated diene-based graft polymer is When the average number of points is Y, (W/Y) preferably satisfies the relationship of the following formula (4).
0.5≦(W/Y) (4)

The above (W/Y) is more preferably 0.6 or more (0.6≦(W/Y)), and more preferably 0.8 or more (0.8≦(W/Y)). In the present invention, the average number W of the side chains (b) directly bonded to the branch points per molecule of the conjugated diene-based graft polymer is , In the following step (A-1), the charged amount (number of moles) per active terminal of the active terminal polymer (I) to be the side chain (b) of the conjugated diene graft polymer and the functional group-modified conjugated diene polymer It is obtained from the following formula (9) using the charged amount (number of moles) of coalescence (F).
(Average number W of side chains (b) directly bonded to the branch point per molecule of conjugated diene-based graft polymer) = (Preparation per active end of active terminal polymer (I) to be side chain (b) Amount (number of moles))/(Feed amount (number of moles) of functional group-modified conjugated diene-based polymer (F)) (9)

The average number Y of branch points per molecule of the conjugated diene-based graft polymer is calculated by the method described above. When the above (W/Y) is less than 0.5, the fluidity of the conjugated diene-based graft polymer tends to be low, and the balance between workability and mechanical properties tends to be poor.

The degree of branching of the conjugated diene-based graft polymer is the slope (α _s ) of the log-log plot of the radius of gyration (R) against the absolute weight average molecular weight (Mw) of the conjugated diene-based graft polymer. , or from the slope (αη) of a log-log plot of the intrinsic viscosity (η) against the absolute weight average molecular weight (Mw) of the conjugated diene-based graft polymer. Random coil chains of ordinary linear polymers show values of about 0.6 to 0.8 for both α _s and αη, and values less than 0.6 suggest the presence of branched chains. The value of α _s or αη of the conjugated diene-based graft polymer of the present invention is preferably less than 0.6, more preferably 0.55 or less, even more preferably 0.50 or less. A double-logarithmic plot of the weight average molecular weight (Mw) and the radius of gyration (R) or intrinsic viscosity (η) of the conjugated diene-based graft polymer can be obtained by, for example, the SEC-MALS-VISCO method. The SEC-MALS-VISCO method is a type of liquid chromatography (SEC) that separates polymer chains based on the difference in molecular size (hydrodynamic volume). (MALS) and a viscosity detector (VISCO) can be combined to calculate the radius of gyration and intrinsic viscosity for each molecular weight of the polymer solution size-fractionated by SEC. When the value of α _s or αη of the conjugated diene-based graft polymer of the present invention is within the above range, the fluidity of the conjugated diene-based graft polymer is improved, and the balance between workability and mechanical properties tends to be excellent.

In the conjugated diene-based graft polymer of the present invention, the average number W of side chains (b) directly bonded to the branch points per molecule of the conjugated diene-based graft polymer is preferably 1 or more, and is 2 or more. is more preferable, and 3 or more is even more preferable. The average number W of the side chains (b) is calculated by the method described above. If the average number W of the side chains (b) is less than 1, the fluidity of the conjugated diene-based graft polymer tends to be low, resulting in poor balance between workability and mechanical properties.

The average number W of the side chains (b) is, for example, the active terminal polymer (I ) and the functional group-modified conjugated diene-based polymer (F), the amount can be adjusted within a desired range. For example, (amount (number of moles) charged of active terminal polymer (I))/(amount (number of moles) charged of functional group-modified conjugated diene polymer (F)) = 4/1, the side chain (b ) is four on average. However, the upper limit of W is the number of functional groups V per molecule of the functional group-modified conjugated diene polymer (F).

The combination of the main chain (a) polymer and side chain (b) polymer contained in the conjugated diene-based graft polymer is not particularly limited, and may be the same or different, and is designed according to the purpose. Is possible. The fact that the polymer forming the main chain (a) and the polymer forming the side chain (b) are different means that at least one selected from the group consisting of (i) to (iv) below is different.
(i) The molecular weight of the polymer that forms the main chain (a) is different from the molecular weight of the polymer that forms the side chain (b).
(ii) The type or combination of types of monomer units in the polymer that forms the main chain (a) is different from the type or combination of types of monomer units in the polymer that forms the side chain (b).
(iii) When the main chain (a) and the side chain (b) each contain a plurality of monomer units of the same type, the monomer unit composition ratio of the polymer that becomes the main chain (a) is side It differs from the monomer unit composition ratio of the polymer that forms the chain (b).
(iv) When the main chain (a) and the side chain (b) each contain a conjugated diene unit, the vinyl content of the conjugated diene unit of the polymer that becomes the main chain (a) is the same as that of the side chain (b). different from the vinyl content of the conjugated diene units of the polymer.

In the conjugated diene-based graft polymer of the present invention, 50% by mass or more of the total monomer units constituting the polymer is at least one monomer unit selected from the group consisting of butadiene and isoprene. This is a preferred embodiment. The total content of butadiene units and isoprene units is more preferably 60 to 100% by mass, even more preferably 70 to 100% by mass, based on the total monomer units of the conjugated diene graft polymer.

The content of monomer units other than butadiene units and isoprene units in the conjugated diene-based graft polymer of the present invention is preferably 50% by mass or less, more preferably 40% by mass or less, and 30% by mass. More preferred are: For example, if the aromatic vinyl compound unit is less than the above range, the processability of the conjugated diene-based graft polymer of the present invention tends to be improved.

In one embodiment, the weight average molecular weight (Mw) of the conjugated diene-based graft polymer of the present invention is preferably 5,000 or more and 1,000,000 or less, preferably 30,000 or more and 1,000,000 or less, More than 100,000 and 1,000,000 or less are more preferable. When the Mw of the conjugated diene-based graft polymer is within the above range, it tends to be excellent in the ability to pass through the manufacturing process and to be economically efficient. In addition, the processability of polymer compositions containing conjugated diene-based graft polymers tends to improve.

The molecular weight distribution (Mw/Mn) of the conjugated diene-based graft polymer of the present invention is preferably 1.0 to 20.0, more preferably 1.0 to 10.0, even more preferably 1.0 to 5.0. 1.0 to 2.0 is particularly preferred. When Mw/Mn is within the above range, variation in viscosity of the conjugated diene-based graft polymer is small, which is more preferable. In the present invention, Mn means number average molecular weight, and Mn is the number average molecular weight in terms of standard polystyrene obtained from GPC measurement. Further, the molecular weight distribution (Mw/Mn) means the ratio (Mw/Mn) of the weight average molecular weight (Mw) converted to standard polystyrene and the number average molecular weight (Mn) obtained by GPC measurement.

The melt viscosity of the conjugated diene-based graft polymer of the present invention measured at 38° C. is preferably 0.1 to 2,000 Pa s, more preferably 0.1 to 1500 Pa s, and more preferably 0.1 to 1000 Pa s. More preferred. When the melt viscosity of the conjugated diene-based graft polymer is within the above range, it tends to be excellent in the ability to pass through the manufacturing process and to be economically efficient. In the present invention, the melt viscosity of the conjugated diene-based graft polymer is a value measured at 38°C with a Brookfield viscometer.

The vinyl content of the conjugated diene-based graft polymer of the present invention is not particularly limited, but in one embodiment, it is preferably 90 mol% or less, more preferably 80 mol% or less, and even more preferably 70 mol% or less. The vinyl content of the conjugated diene-based graft polymer is preferably 0.5 mol % or more, more preferably 1 mol % or more.

The vinyl content of the conjugated diene graft polymer can be designed according to the purpose. For example, when the vinyl content is less than 50 mol%, the glass transition temperature (Tg) of the conjugated diene graft polymer described later becomes low, and the conjugated diene-based graft polymer tends to be excellent in fluidity and low-temperature properties. Moreover, when it is 50 mol % or more, the reactivity of the conjugated diene-based graft polymer tends to be excellent.

The glass transition temperature (Tg) of the conjugated diene-based graft polymer is derived from butadiene units, isoprene units and butadiene units, the vinyl content of conjugated diene units other than isoprene units, the type of conjugated diene units, and monomers other than conjugated dienes. -150 to 50°C is preferred, -130 to 50°C is more preferred, and -130 to 30°C is even more preferred. When the Tg is within the above range, for example, it is possible to prevent the viscosity from becoming high, which facilitates handling.

The mass ratio of the main chain and side chains in the conjugated diene-based graft polymer of the present invention is preferably in the range of 10/90 to 90/10, more preferably in the range of 15/85 to 80/20, and 20/80 to 70. A range of /30 is more preferred. When the mass ratio of the main chain to the side chain is within the above range, the processability of the polymer composition containing the conjugated diene graft polymer tends to be improved.

The conjugated diene-based graft polymer of the present invention preferably has a catalyst residue amount derived from the polymerization catalyst used for its production in the range of 0 to 200 ppm in terms of metal. For example, when an organic alkali metal such as an organic lithium compound as described later is used as a polymerization catalyst for producing a conjugated diene-based graft polymer, the metal used as a reference for the amount of catalyst residue is an alkali such as lithium. become metal. When the amount of the catalyst residue is within the above range, the tackiness does not decrease during processing, etc., and the heat resistance of the conjugated diene-based graft polymer of the present invention is improved. The amount of catalyst residue derived from the polymerization catalyst used for producing the conjugated diene graft polymer is more preferably 0 to 150 ppm, more preferably 0 to 100 ppm in terms of metal. The catalyst residue amount can be measured by using, for example, an inductively coupled plasma mass spectrometer (ICP-MS) or a polarized Zeeman atomic absorption spectrophotometer.

As a method for adjusting the catalyst residue amount of the conjugated diene graft polymer to such a specific amount, there is a method of purifying the conjugated diene graft polymer and sufficiently removing the catalyst residue. As a method for purification, washing with water or hot water, an organic solvent represented by methanol, acetone, or the like, or a supercritical fluid carbon dioxide is preferable. The number of washings is preferably from 1 to 20 times, more preferably from 1 to 10 times, from an economical point of view. The washing temperature is preferably 20 to 100°C, more preferably 40 to 90°C. In addition, by removing impurities that inhibit polymerization by distillation or an adsorbent before the polymerization reaction and increasing the purity of the monomers, the necessary amount of the polymerization catalyst can be reduced. The catalyst residue amount can be reduced.

The conjugated diene-based graft polymer of the present invention preferably has a halogen content of 0 to 1,000 ppm. For example, when a silyl chloride-modified conjugated diene polymer is used as the functional group-modified conjugated diene polymer (F) for producing a conjugated diene graft polymer, the standard halogen is chlorine. When the halogen content is within the above range, transparency, heat resistance and weather resistance tend to be improved. The halogen content of the conjugated diene-based graft polymer is more preferably 0 to 500 ppm, still more preferably 0 to 100 ppm. The halogen content can be measured, for example, by using combustion ion chromatography.

As a method for adjusting the halogen content of the conjugated diene-based graft polymer to such a specific amount, as the functional group-modified conjugated diene-based polymer (F), which is a raw material for producing the conjugated diene-based graft polymer, A method using an alkoxysilane-modified conjugated diene-based polymer that does not produce a halide as a by-product can be mentioned.

<Method for producing conjugated diene-based graft polymer>
The method for producing the conjugated diene-based graft polymer of the present invention is not particularly limited. A method of polymerizing a macromonomer obtained by reacting a main chain with a monomer that forms a main chain structural unit, a method of reacting a pre-synthesized main chain polymer and an organic alkali metal compound in the presence of tetramethylethylenediamine A method of polymerizing a monomer that will be a constituent unit of a side chain after lithiating the main chain by allowing a polymer having two active terminals to be a constituent of the main chain and a constituent of the side chain A method in which a mixture of polymers having two active terminals is prepared, and a coupling agent having three or more reactive sites is added to the mixture for reaction. A method of modifying and reacting the functional group-modified polymer with an active terminal of a polymer obtained by polymerizing a monomer to be a structural unit of a side chain. Among these production methods, the weight average molecular weight and vinyl content of the main chain and side chains of the conjugated diene-based graft polymer, the number of side chains, etc. can be freely controlled, and the desired functional groups can be easily introduced. For this reason, the method of reacting the functional group-modified polymer that constitutes the constituent of the main chain with the active terminal of the polymer obtained by polymerizing the monomer that constitutes the constituent unit of the side chain is preferred.

As the method for producing the conjugated diene-based graft polymer of the present invention, a production method including the following steps (A-1) and (B) is preferred.

(A-1) A functional group-modified conjugated diene-based polymer having an active terminal polymer (I) represented by the following formula (I) and a portion containing a functional group represented by the following formula (II) as a branched chain ( F) to prepare a conjugated diene-based graft polymer (G)

PX (I)
(In formula (I), P represents a polymer chain containing at least one monomer unit selected from the group consisting of conjugated diene units and aromatic vinyl compound units, and X represents an anionic polymerization active terminal.)

（式（ＩＩ）中、Ｖは、アルコキシ基または水酸基を示し、ＺはＳｉ、Ｓｎ、Ｇｅ、Ｐｂ、Ｐ、Ｂ、またはＡｌであり、Ｒ¹は炭素数６～１２のアリール基、炭素数１～１２のアルキル基、または水素原子を示し、Ｎは前記Ｚの価数を示し、ｎは下記式（５）を満たす整数であり；
１≦ｎ≦Ｎ－１ （５）
ｎが２以上の場合、Ｖは同一でも異なっていてもよく、Ｎ－ｎが２以上の場合、Ｒ¹は同一でも異なっていてもよく、分岐鎖が主鎖に対し、複数含まれる場合には、Ｚは同一でも異なっていてもよい。）；および
（Ｂ）得られた共役ジエン系グラフト重合体を回収する工程。

(In formula (II), V represents an alkoxy group or a hydroxyl group, Z is Si, Sn, Ge, Pb, P, B, or Al, R ¹ is an aryl group having 6 to 12 carbon atoms, 1 to 12 alkyl groups or hydrogen atoms, N represents the valence of Z, n is an integer satisfying the following formula (5);
1≤n≤N-1 (5)
When n is 2 or more, V may be the same or different; when Nn is 2 or more, R ¹ may be the same or different; , Z may be the same or different. ); and (B) a step of recovering the obtained conjugated diene-based graft polymer.

The branched chain of the functional group-modified conjugated diene-based polymer (F) means a portion other than the main chain of the functional group-modified conjugated diene-based polymer (F). As with the main chain (a) in the polymer, it refers to the entire portion derived from all monomer units including conjugated diene units constituting the main chain.

[Step (A-1)]
The active terminal polymer (I) used in the above step (A-1) can be produced using a known polymerization method. For example, in a solvent inert to the polymerization terminal, using an anionically polymerizable active metal or active metal compound as an initiator, optionally in the presence of a polar compound, by anionically polymerizing a monomer, the active terminal is polymerized. Coalescence (I) can be obtained. The P of this active terminal polymer (I) becomes the side chain (b) of the graft polymer obtained in the present invention.

Specific Examples of Monomers Constituting the Active Terminal Polymer (I), Description of Preferred Embodiments, etc., and Specific Examples and Preferred Embodiments of the Monomer Units Contained in the Active Terminal Polymer (I) is the same as the side chain (b) of the conjugated diene-based graft polymer.

As the anionically polymerizable active metal or active metal compound, an organic alkali metal compound is preferred, and an organic lithium compound is more preferred. Examples of the organic lithium compound include methyllithium, ethyllithium, n-butyllithium, sec-butyllithium, tert-butyllithium, and pentyllithium.

Examples of the solvent include aliphatic hydrocarbons such as n-butane, n-pentane, isopentane, n-hexane, n-heptane and isooctane; alicyclic hydrocarbons such as cyclopentane, cyclohexane and methylcyclopentane; and benzene. , toluene, and xylene.

A polar compound may be added during the anionic polymerization. Polar compounds are commonly used in anionic polymerizations to control the microstructure (vinyl content) of the conjugated diene units without quenching the reaction. Examples of polar compounds include ether compounds such as dibutyl ether, tetrahydrofuran and ethylene glycol diethyl ether; tertiary amines such as tetramethylethylenediamine and trimethylamine; alkali metal alkoxides and phosphine compounds. The polar compound is generally used in an amount of 0.01 to 1000 mol per 1 mol of the organic alkali metal compound.

The temperature for the anionic polymerization is usually in the range of -80 to 150°C, preferably in the range of 0 to 100°C, more preferably in the range of 10 to 90°C. The mode of polymerization may be either a batchwise system or a continuous system.

The P of the active terminal polymer (I) finally becomes the side chain (b) of the conjugated diene-based graft polymer of the present invention. The description of the weight average molecular weight (Mw) of P, the vinyl content, the preferable Tg, etc. of the active terminal polymer (I) is the same as that of the side chain (b) of the graft polymer of the present invention.

In the above step (A-1), the functional group-modified conjugated diene-based polymer (F) is obtained, for example, by modifying the unmodified conjugated diene-based polymer (F') with a functional group in the modification step described below. . The method for producing the unmodified conjugated diene-based polymer (F′) is not particularly limited, but for example, emulsion polymerization and solution polymerization are preferred, and from the viewpoint of the molecular weight distribution of the resulting polymer, solution polymerization is more preferred. . The portion other than the functional group-modified conjugated diene polymer (F) becomes the main chain (a) of the conjugated diene graft polymer of the present invention.

Specific examples, preferred examples, and preferred content of the conjugated diene, which is a monomer unit constituting the unmodified conjugated diene-based polymer (F'), and other monomers other than the conjugated diene (aromatic vinyl Compound), specific examples, preferred examples, preferred content, etc. are the same as those for the main chain (a) of the conjugated diene-based graft polymer. In addition, the description of the weight average molecular weight (Mw), vinyl content, preferred aspects of Tg, etc. of the unmodified conjugated diene-based polymer (F′) is the same as the description of the main chain (a) of the conjugated diene-based graft polymer. be.

As the emulsion polymerization method, which is an example of the method for producing the unmodified conjugated diene-based polymer (F′), a known method or a known method can be applied. For example, a monomer containing a predetermined amount of conjugated diene is emulsified and dispersed in a dispersion medium in the presence of an emulsifier, and emulsion polymerized with a radical polymerization initiator.

Examples of emulsifiers include salts of long-chain fatty acids having 10 or more carbon atoms and rosinates. Examples of long-chain fatty acid salts include potassium salts or sodium salts of fatty acids such as capric acid, lauric acid, myristic acid, palmitic acid, oleic acid and stearic acid.

Water is usually used as the dispersion medium. The dispersion medium may contain a water-soluble organic solvent such as methanol or ethanol as long as the stability during polymerization is not impaired.

Examples of radical polymerization initiators include persulfates such as ammonium persulfate and potassium persulfate, organic peroxides, and hydrogen peroxide.

A chain transfer agent may be used to adjust the molecular weight of the resulting unmodified conjugated diene polymer (F'). Examples of chain transfer agents include mercaptans such as t-dodecylmercaptan and n-dodecylmercaptan; carbon tetrachloride, thioglycolic acid, diterpene, terpinolene, γ-terpinene, α-methylstyrene dimer and the like.

The temperature for emulsion polymerization can be appropriately set depending on the type of radical polymerization initiator to be used, etc., but it is usually in the range of 0 to 100°C, preferably in the range of 0 to 60°C. The polymerization mode may be either continuous polymerization or batch polymerization.

Polymerization reactions can be terminated by the addition of a polymerization terminating agent. Examples of the polymerization terminator include amine compounds such as isopropylhydroxylamine, diethylhydroxylamine and hydroxylamine, quinone compounds such as hydroquinone and benzoquinone, and sodium nitrite.

After termination of the polymerization reaction, an anti-aging agent may be added as necessary. After stopping the polymerization reaction, unreacted monomers are removed from the obtained latex if necessary, and then salts such as sodium chloride, calcium chloride and potassium chloride are used as coagulants, and if necessary nitric acid, sulfuric acid and the like are added. After the unmodified conjugated diene polymer (F') is coagulated while adjusting the pH of the coagulation system to a predetermined value by adding an acid, the polymer is recovered by separating the dispersion medium. Then, the unmodified conjugated diene-based polymer (F') is obtained by washing with water, dehydration, and drying. At the time of coagulation, if necessary, the latex and an extender oil made into an emulsified dispersion may be mixed in advance and recovered as an oil-extended unmodified conjugated diene polymer (F').

As the solution polymerization method, which is an example of the method for producing the unmodified conjugated diene-based polymer (F′), a known method or a known method can be applied. For example, in a solvent, using a Ziegler-based catalyst, a metallocene-based catalyst, or an anionically polymerizable active metal or active metal compound as an initiator, optionally in the presence of a polar compound, a monomer containing a conjugated diene Polymerize the body.

Examples of solvents include aliphatic hydrocarbons such as n-butane, n-pentane, isopentane, n-hexane, n-heptane and isooctane; alicyclic hydrocarbons such as cyclopentane, cyclohexane and methylcyclopentane; Aromatic hydrocarbons such as toluene and xylene can be used.

The initiator is preferably an anionically polymerizable active metal or an active metal compound, more preferably an anionically polymerizable active metal compound.

Examples of anionically polymerizable active metals include alkali metals such as lithium, sodium and potassium; alkaline earth metals such as beryllium, magnesium, calcium, strontium and barium; lanthanoid rare earth metals such as lanthanum and neodymium. . Among these, alkali metals and alkaline earth metals are preferred, and alkali metals are more preferred.

Organic alkali metal compounds are preferred as the anionically polymerizable active metal compound. Examples of organic alkali metal compounds include organic monolithium compounds such as methyllithium, ethyllithium, n-butyllithium, sec-butyllithium, t-butyllithium, hexyllithium, phenyllithium, and stilbenelithium; , 1,4-dilithiobutane, 1,4-dilithio-2-ethylcyclohexane and 1,3,5-trilithiobenzene; and sodium naphthalene, potassium naphthalene and the like. Among these organic alkali metal compounds, organic lithium compounds are preferred, and organic monolithium compounds are more preferred.

The amount of the initiator used can be appropriately set according to the melt viscosity and molecular weight of the unmodified conjugated diene polymer (F') and the functional group-modified conjugated diene polymer (F). It is usually used in an amount of 0.01 to 3 parts by weight per 100 parts by weight of the monomer.

When an organic alkali metal compound is used as an initiator, the organic alkali metal compound can be used as an organic alkali metal amide by reacting it with a secondary amine such as dibutylamine, dihexylamine or dibenzylamine. .

Polar compounds are commonly used in anionic polymerizations to control the microstructure (vinyl content) of the conjugated diene units without quenching the reaction. Examples of polar compounds include ether compounds such as dibutyl ether, tetrahydrofuran and ethylene glycol diethyl ether; tertiary amines such as tetramethylethylenediamine and trimethylamine; alkali metal alkoxides and phosphine compounds. The polar compound is generally used in an amount of 0.01 to 1000 mol per 1 mol of the organic alkali metal compound.

The temperature of the solution polymerization is usually in the range of -80 to 150°C, preferably in the range of 0 to 100°C, more preferably in the range of 10 to 90°C. The mode of polymerization may be either a batchwise system or a continuous system.

The polymerization reaction of the solution polymerization can be terminated by adding a polymerization terminator. Examples of the polymerization terminator include alcohols such as methanol and isopropanol. The resulting polymerization reaction solution is poured into a poor solvent such as methanol to precipitate the unmodified conjugated diene polymer (F′), or the polymerization reaction solution is washed with water, separated, and dried to remove the unmodified polymer. A modified conjugated diene polymer (F') can be isolated.

A functional group-modified conjugated diene polymer (F) having a branched chain containing a functional group represented by the above formula (II) by modifying the unmodified conjugated diene polymer (F′) with a functional group. is not particularly limited, but from the viewpoint of introducing a functional group having a preferred structure, for example, a mercapto group (—SH ), a method of introducing a functional group derived from an alkoxysilane compound by radical addition reaction of a compound having a And a method of introducing a functional group derived from an alkoxysilane compound by hydrosilylating in the presence of a co-catalyst that is used as necessary. Among these production methods, the method of radical addition reaction of a compound having a mercapto group (—SH) is preferable from the viewpoint of the availability of modifying reagents and catalysts and the production cost, and the resulting functional group-modified conjugated diene polymer From the viewpoint of the stability of coalescence (F), a method of introducing a functional group derived from an alkoxysilane compound by hydrosilylation is preferred.

A functional group derived from an alkoxysilane compound is introduced by subjecting a compound having a mercapto group (--SH) to a carbon-carbon unsaturated bond contained in the unmodified conjugated diene-based polymer (F') to a radical addition reaction. As a method, a method of subjecting a silane compound (IV) represented by the following formula (IV) to a carbon-carbon unsaturated bond contained in the unmodified conjugated diene polymer (F') to a radical addition reaction is preferred.

(In formula (IV), R ⁴ represents a divalent alkylene group having 1 to 6 carbon atoms, R ⁵ and R ⁶ each independently represent an aryl group having 6 to 12 carbon atoms, an alkyl group having 1 to 12 carbon atoms, represents a group or a hydrogen atom, n is an integer of 1 to 3, and when n is 2 or more, R ⁵ may be the same or different, and when 3-n is 2 or more, R ⁶ may be the same may be different.)

Examples of the silane compound (IV) include mercaptomethylenemethyldiethoxysilane, mercaptomethylenetriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, 2-mercaptoethylmethoxydimethylsilane, 2- Mercaptoethylethoxydimethylsilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropyldimethoxymethylsilane, 3-mercaptopropyldiethoxymethylsilane, 3-mercaptopropyldimethoxyethylsilane, 3-mercapto Propyldiethoxyethylsilane, 3-mercaptopropylmethoxydimethylsilane, 3-mercaptopropylethoxydimethylsilane and the like. These silane compounds may be used singly or in combination of two or more.

The mercapto group (-SH) of the silane compound (IV) is derived from the silane compound (IV) by a radical addition reaction to the carbon-carbon unsaturated bond contained in the unmodified conjugated diene polymer (F'). A functional group-modified conjugated diene polymer (F) having, as a functional group, a partial structure represented by the following formula (V) is obtained.

（式（Ｖ）中、Ｒ⁴、Ｒ⁵、Ｒ⁶、およびｎの定義は式（ＩＶ）と同一である。）

(In formula (V), definitions of R ⁴ , R ⁵ , R ⁶ and n are the same as in formula (IV).)

The method of adding the silane compound (IV) to the unmodified conjugated diene polymer (F') is not particularly limited. Furthermore, a method of adding a radical generator as necessary and heating in the presence or absence of an organic solvent can be employed. The radical generator to be used is not particularly limited, and generally commercially available organic peroxides, azo compounds, hydrogen peroxide and the like can be used.

Examples of the organic peroxide include methyl ethyl ketone peroxide, cyclohexanone peroxide, 3,3,5-trimethylcyclohexanone peroxide, methyl cyclohexanone peroxide, acetylacetone peroxide, and 1,1-bis(t-butylperoxy). -3,3,5-trimethylcyclohexane, 1,1-bis(t-butylperoxy)cyclohexane, 1,1-bis(t-hexylperoxy)cyclohexane, 2,2-bis(t-butylperoxy) Butane, t-butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, paramenthane hydroperoxide, 2,5-dimethylhexane 2,5-dihydroperoxide, 1,1,3,3-tetra methyl butyl hydroperoxide, di-t-butyl peroxide, t-butylcumyl peroxide, dicumyl peroxide, bis(t-butylperoxyisopropyl)benzene, 2,5-dimethyl-2,5-di(t- Butylperoxy)hexane, 2.5-hexanoyl peroxide, lauroyl peroxide, succinic peroxide, benzoyl peroxide and its substituted products, 2,4-dichlorobenzoyl peroxide, metatoluoyl peroxide, diisopropylperoxy Dicarbonate, t-butyl-2-ethylhexanoate, di-2-ethylhexyl peroxydicarbonate, dimethoxyisopropyl peroxycarbonate, di(3-methyl-3-methoxybutyl) peroxydicarbonate, t-butyl peroxy Oxyacetate, t-butyl peroxypivalate, t-butyl peroxyneodecanoate, t-butyl peroxyoctanoate, t-butyl peroxy 3,3,5-trimethylhexanoate, t-butyl peroxy oxylaurate, t-butylperoxycarbonate, t-butylperoxybenzoate, t-butylperoxyisobutyrate and the like.

Examples of the azo compounds include 2,2′-azobisisobutyronitrile, 1,1′-azobis(cyclohexane-1-carbonitrile), 2,2′-azobis(2-methylbutyronitrile) , 2,2′-azobis(2,4-dimethylvaleronitrile), 2,2′-azobis(2,4-dimethyl-4-methoxyvaleronitrile), 2,2′-azobis(2-(2-imidazoline -2-yl)propane), 2,2′-azobis(2,4,4-trimethylpentane), 2,2′-azobis(2-methylpropane), 2,2′-azobis(2-hydroxymethylpropion nitrile), 4,4'-azobis (4-cyanovaleric acid), dimethyl 2,2'-azobis (2-methylpropionate), 2-cyano-2-propylazoformamide, 2-phenylazo-4- methoxy-2,4-dimethylvaleronitrile and the like.
The above radical generators may be used alone or in combination of two or more.

Organic solvents used in the above method generally include hydrocarbon solvents and halogenated hydrocarbon solvents. Among these organic solvents, hydrocarbon solvents such as n-butane, n-hexane, n-heptane, cyclohexane, benzene, toluene and xylene are preferred.
The above organic solvents may be used singly or in combination of two or more.

Furthermore, when the reaction for adding the modifying compound is carried out by the above method, an antioxidant may be added from the viewpoint of suppressing side reactions.
Preferred anti-aging agents used at this time include, for example, 2,6-di-t-butyl-4-methylphenol (BHT), 2,2'-methylenebis(4-methyl-6-t-butylphenol), 4,4 '-thiobis(3-methyl-6-t-butylphenol), 4,4'-butylidenebis(3-methyl-6-t-butylphenol) (AO-40), 3,9-bis[1,1-dimethyl- 2-[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane (AO-80), 2,4-bis[(octylthio)methyl]-6-methylphenol (Irganox 1520L), 2,4-bis[(dodecylthio)methyl]-6-methylphenol (Irganox 1726), 2-[1-(2-hydroxy- 3,5-di-t-pentylphenyl)ethyl]-4,6-di-t-pentylphenyl acrylate (SumilizerGS), 2-t-butyl-6-(3-t-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate (Sumilizer GM), 6-t-butyl-4-[3-(2,4,8,10-tetra-t-butyldibenzo[d,f][1,3,2]dioxa Phosphepin-6-yloxy)propyl]-2-methylphenol (SumilizerGP), Tris(2,4-di-t-butylphenyl)phosphite (Irgafos168), Dioctadecyl 3,3'-dithiobispropionate , hydroquinone, p-methoxyphenol, N-phenyl-N'-(1,3-dimethylbutyl)-p-phenylenediamine (Nocrac 6C), bis(2,2,6,6-tetramethyl-4-piperidyl) Sebacate (LA-77Y), N,N-dioctadecylhydroxylamine (IrgastabFS042), bis(4-t-octylphenyl)amine (Irganox5057) and the like.
The anti-aging agents may be used singly or in combination of two or more.

The amount of the antioxidant to be added is preferably 0 to 10 parts by mass, more preferably 0 to 5 parts by mass, per 100 parts by mass of the unmodified conjugated diene polymer (F').

The temperature in the reaction for adding the silane compound (IV) to the unmodified conjugated diene polymer (F') is preferably 10 to 200°C, more preferably 50 to 180°C. The reaction time is preferably 1 to 200 hours, more preferably 1 to 100 hours, even more preferably 1 to 50 hours.

Derived from an alkoxysilane compound by hydrosilylating the carbon-carbon unsaturated bond contained in the unmodified conjugated diene-based polymer (F') in the presence of a platinum compound-containing catalyst and an optional co-catalyst. As a method for introducing a functional group, the carbon-carbon unsaturated bond contained in the unmodified conjugated diene polymer (F') is treated in the presence of a platinum compound-containing catalyst, preferably in the presence of a platinum compound-containing catalyst and a co-catalyst. A method of hydrosilylation with a silane compound (VI) represented by the following formula (VI) below is preferred.

（式（ＶＩ）中、Ｒ⁷、およびＲ⁸はそれぞれ独立に炭素数６～１２のアリール基、または炭素数１～１２のアルキル基を示し、ｎは１～３の整数であり、ｎが２以上の場合、Ｒ⁷は同一でも異なっていてもよく、３－ｎが２以上の場合、Ｒ⁸は同一でも異なっていてもよい。）

(In formula (VI), R ⁷ and R ⁸ each independently represent an aryl group having 6 to 12 carbon atoms or an alkyl group having 1 to 12 carbon atoms, n is an integer of 1 to 3, and n is When 2 or more, R ⁷ may be the same or different, and when 3-n is 2 or more, R ⁸ may be the same or different.)

Examples of the silane compound (VI) include trimethoxysilane, methyldimethoxysilane, dimethylmethoxysilane, triethoxysilane, methyldiethoxysilane, and dimethylethoxysilane. These silane compounds may be used singly or in combination of two or more.

A functional group derived from the silane compound (VI), specifically can obtain a functional group-modified conjugated diene polymer (F) having a partial structure represented by the following formula (VII) as a functional group.

（式（ＶＩＩ）中、Ｒ⁷、Ｒ⁸、およびｎの定義は式（ＩＶ）と同一である。）

(In formula (VII), definitions of R ⁷ , R ⁸ and n are the same as in formula (IV).)

The platinum compound-containing catalyst used in the hydrosilylation reaction is not particularly limited, but examples include chloroplatinic acid, an alcohol solution of chloroplatinic acid, platinum-1,3-divinyl-1,1,3,3-tetramethyl Toluene or xylene solution of disiloxane complex, tetrakistriphenylphosphine platinum, dichlorobistriphenylphosphine platinum, dichlorobisacetonitrile platinum, dichlorobisbenzonitrile platinum, dichlorocyclooctadiene platinum, platinum-carbon, platinum-alumina, platinum- Supported catalysts such as silica can be used.
From the viewpoint of selectivity in hydrosilylation, a zerovalent platinum complex is preferred, and a toluene or xylene solution of a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex is more preferred.

The amount of the platinum compound-containing catalyst used is not particularly limited, but from the viewpoint of reactivity, productivity, etc., the amount of platinum atoms contained is 1 × 10 ^-7 per 1 mol of the silane compound (VI). An amount of up to 1×10 ⁻² mol is preferable, and an amount of 1×10 ⁻⁷ to 1×10 ⁻³ mol is more preferable.

As a co-catalyst in the above reaction, it is preferable to use one or more selected from ammonium salts of inorganic acids, acid amide compounds and carboxylic acids.

Examples of ammonium salts of inorganic acids include ammonium chloride, ammonium sulfate, ammonium amidosulfate, ammonium nitrate, monoammonium dihydrogen phosphate, diammonium hydrogen phosphate, triammonium phosphate, ammonium diphosphite, ammonium carbonate, and ammonium hydrogen carbonate. , ammonium sulfide, ammonium borate, and ammonium borofluoride. Among these, ammonium salts of inorganic acids having a pKa of 2 or more are preferable, and ammonium carbonate and ammonium hydrogencarbonate are more preferable.

Examples of acid amide compounds include formamide, acetamide, N-methylacetamide, N,N-dimethylacetamide, propionamide, acrylamide, malonamide, succinamide, maleamide, fumaramamide, benzamide, phthalamide, palmitic acid amide, and stearic acid amide. mentioned.

Examples of carboxylic acids include formic acid, acetic acid, propionic acid, butyric acid, methoxyacetic acid, pentanoic acid, caproic acid, heptanoic acid, octanoic acid, lactic acid, and glycolic acid. Among these, formic acid, acetic acid and lactic acid are preferred, and acetic acid is more preferred.

The amount of co-catalyst used is not particularly limited, but from the viewpoint of reactivity, selectivity, cost, etc., 1×10 ⁻⁵ to 5×10 ⁻¹ mol per 1 mol of the silane compound (VI) is used. It is preferably 1×10 ^-4 to 5×10 ^-1 mol.

Although the hydrosilylation reaction proceeds without a solvent, a solvent can also be used. Solvents that can be used include, for example, hydrocarbon solvents such as pentane, hexane, cyclohexane, heptane, isooctane, benzene, toluene, and xylene; ether solvents such as diethyl ether, tetrahydrofuran, and dioxane; ester solvents; aprotic polar solvents such as N,N-dimethylformamide; and chlorinated hydrocarbon solvents such as dichloromethane and chloroform. These solvents may be used singly or in combination of two or more.

The reaction temperature in the above hydrosilylation reaction is not particularly limited, and is usually 0.degree. In order to obtain an appropriate reaction rate, it is preferable to carry out the reaction under heating. From this point of view, the reaction temperature is more preferably 40 to 110°C, further preferably 40 to 90°C. The reaction time is also not particularly limited, and is usually about 1 to 60 hours, preferably 1 to 30 hours, more preferably 1 to 20 hours.

In the functional group-modified conjugated diene-based polymer (F), one functional group having a partial structure represented by formula (V) or formula (VII) may be contained singly or two or more may be contained. may Therefore, the functional group-modified conjugated diene-based polymer (F) may be a diene-based polymer modified with one compound selected from the group consisting of the silane compound (IV) and the silane compound (VI). , or a diene-based polymer modified with two or more compounds.

Z in the above formula (II) is preferably Si or Sn, more preferably Si, from the viewpoint of the affinity and stability of the obtained conjugated diene-based graft polymer with the polar material.

From the viewpoint of the affinity and stability of the obtained conjugated diene-based graft polymer with polar materials and the reactivity in the coupling step described later, V in the above formula (II) is preferably an alkoxy group having 1 carbon atom. Alkoxy groups of ∼5 are more preferred, and methoxy and ethoxy groups are particularly preferred.

n in the above formula (II) is an integer that satisfies the above formula (5). From the viewpoint of control, it is preferably 2 or more, more preferably 3 or more, and particularly preferably the same as the valence of Z.

The average number of moieties represented by the above formula (II) per molecule of the functional group-modified conjugated diene polymer (F) is preferably 1 to 50, more preferably 2 to 30, and further preferably 3 to 20. preferable.

The average number of functional groups V in the above formula (II) per molecule of the functional group-modified conjugated diene polymer (F) is preferably 2 to 150, more preferably 4 to 90, and 6 to 60. More preferred.

The average number of functional groups V in the above formula (II) per molecule of the functional group-modified conjugated diene polymer (F) is the functional group of the functional group V contained in the functional group-modified conjugated diene polymer (F) It is obtained from the following formula (10) using the equivalent weight (g/eq) and the number average molecular weight (Mn) in terms of standard polystyrene.
(Average number of functional groups V in the above formula (II) per molecule of functional group-modified conjugated diene polymer (F)) = [(number average molecular weight Mn) / (molecular weight of styrene unit) × (conjugated diene and Average molecular weight of monomer units other than conjugated diene optionally included)]/(Functional group equivalent of functional group V) (10)

The functional group equivalent of the functional group V contained in the functional group-modified conjugated diene-based polymer (F) is the conjugated diene bonded per functional group V and other than the conjugated diene optionally contained. It means the mass of the monomer. The equivalent weight of the functional group is calculated from the area ratio of the peak derived from the functional group V and the peak derived from the main chain of the polymer using ¹ H-NMR. In addition, the peak derived from the functional group V refers to the peak derived from an alkoxy group and a hydroxyl group.

The mixing ratio of the unmodified conjugated diene polymer (F′) and the silane compound (IV) or silane compound (VI) is, for example, the formula (II ) may be appropriately set so that the average number of functional groups V contained in ) becomes a desired value. ) in a mass ratio of 0.3 to 100.

The preferred ranges of Mw and vinyl content of the functional group-modified conjugated diene polymer (F) are the same as those of the unmodified conjugated diene polymer (F').

The melt viscosity of the functional group-modified conjugated diene polymer (F) measured at 38° C. is preferably 0.1 to 2,000 Pa s, more preferably 0.1 to 1500 Pa s, and 0.1 to 1000 Pa. • s is more preferred. When the melt viscosity of the functional group-modified conjugated diene-based polymer (F) is within the above range, it tends to be excellent in the ability to pass the process during production and to be economically efficient.

In step (A-1), by reacting the active terminal polymer (I) with the functional group-modified conjugated diene polymer (F), the functional group V in the moiety represented by the formula (II) and the A substitution reaction of the active terminal polymer (I) occurs to form a conjugated diene-based graft polymer in which the active terminal polymer (I) as a side chain is bonded to the heteroatom Z, which is a branch point (hereinafter referred to as the present invention). the reaction is called a coupling reaction). The coupling reaction and the unreacted functional group V (at least one remaining functional group selected from the group consisting of an alkoxy group and a hydroxyl group) in the inactivation step described later remain as they are or are hydrolyzed. By doing so, at least one functional group (c) selected from the group consisting of alkoxy groups and hydroxyl groups bonded to the branch points of the conjugated diene-based graft polymer is formed.

The average number W of the side chains (b) directly bonded to the branch points per molecule of the conjugated diene-based graft polymer is determined by the active terminal polymer (I) and the functional group-modified conjugated diene-based polymer ( It can be adjusted to a desired range depending on the ratio of the charging amount of F). For example, (amount (number of moles) charged of active terminal polymer (I))/(amount (number of moles) charged of functional group-modified conjugated diene polymer (F)) = 4/1, the side chain (b ) is four on average. However, the upper limit of W is the number of functional groups V per molecule of the functional group-modified conjugated diene polymer (F).

The molar ratio of (charged amount of active terminal polymer (I))/(charged amount of functional group-modified conjugated diene polymer (F)) is directly bonded to the branch point per molecule of conjugated diene graft polymer. It may be appropriately set so that the average number W of the side chains (b) to be a desired value, for example, it is preferably 1 to 200, more preferably 2 to 100, 3 to 50 It is even more preferable to have If the molar ratio of (charged amount of active terminal polymer (I))/(charged amount of functional group-modified conjugated diene-based polymer (F)) is less than 1, the number of side chains that can be introduced is less than 200. If it is too large, the coupling rate, which will be described later, tends to decrease.

The above coupling reaction is usually carried out at a temperature of 0 to 100° C. for 0.5 to 50 hours. The functional group-modified conjugated diene-based polymer (F) may be diluted before use, and the solvent for dilution is not particularly limited as long as it is inert to the active terminal and does not adversely affect the reaction. Examples include hexane and cyclohexane. , heptane, octane, decane, toluene, benzene, xylene and other saturated aliphatic or aromatic hydrocarbons.
Also, a Lewis base may be added as an additive during the coupling reaction. Lewis bases include, for example, ethers such as dimethyl ether, diethyl ether and tetrahydrofuran; glycol ethers such as ethylene glycol dimethyl ether and diethylene glycol dimethyl ether; triethylamine, N,N,N',N'-tetramethylethylenediamine, N-methylmorpholine; amines such as These Lewis bases may be used singly or in combination of two or more.

In the coupling reaction, the functional group-modified conjugated diene-based polymer (F) may be added to the reaction vessel in which the active terminal polymer (I) was synthesized, or conversely, the functional group-modified conjugated diene-based polymer (F) may be added to the reactor. The active terminal polymer (I) may be added to the polymer (F). Moreover, as described above, both the active terminal polymer (I) and the functional group-modified conjugated diene polymer (F) may be used after being diluted with a solvent, if necessary. The active terminal polymer (I) may be used alone or in combination of two or more. The functional group-modified conjugated diene polymer (F) may also be used alone. may be used in combination of two or more.

The coupling rate in the above coupling reaction is preferably 50% or higher, more preferably 60% or higher, even more preferably 70% or higher. If the coupling rate is less than 50%, the obtained conjugated diene-based graft polymer has poor mechanical properties, which is not preferable. The coupling rate is obtained from the following formula (10) using the peak area of the component derived from the unreacted active terminal polymer (I) obtained by GPC measurement and the total sum of all peak areas.
(Coupling rate (%)) = [{(sum of all peak areas) - (peak area of component derived from active terminal polymer (I))}/(sum of all peak areas)] x 100 ( 10)

The coupling rate can be increased by increasing the amount of the functional group-modified conjugated diene polymer (F) added, increasing the amount of the Lewis base added, raising the reaction temperature, or lengthening the reaction time. be able to. The coupling reaction can be carried out until the coupling rate reaches the desired range. After that, the coupling reaction can be stopped by adding a polymerization terminator such as methanol or isopropanol.

The number of functional groups (c) directly bonded to the branch point is determined by the molar ratio of the amount of the active terminal polymer (I) and the functional group-modified conjugated diene polymer (F) charged in the coupling reaction, or At least one remaining functional group selected from the group consisting of an alkoxy group and a hydroxyl group (unreacted functional group V) used in the step of inactivating a portion of the reagent used and reaction time, and used as necessary It can be adjusted to a desired range depending on the type and amount of the polar compound added.
As a method for adjusting the number of functional groups (c) directly bonded to the branch point to a desired range, for example, the charged amount of the active terminal polymer (I) and the functional group-modified conjugated diene polymer (F) The average number of functional groups (c) per branch point (X/Y) contained in the conjugated diene-based graft polymer is 1 or more. is less than 1, a method of inactivating a part of the above-described remaining functional groups (unreacted functional groups V).

[Step (A-2)]
In the method for producing the conjugated diene-based graft polymer (G) of the present invention, after step (A-1), in order to adjust the number of functional groups (c) directly bonded to the branch points within a desired range,
(A-2) a step of partially inactivating at least one remaining functional group (unreacted functional group V) selected from the group consisting of alkoxy groups and hydroxyl groups in the conjugated diene-based graft polymer; (hereinafter referred to as the inactivation step);
It is a preferred embodiment to include
The alkoxy groups contained in the resulting conjugated diene-based graft polymer react with the water and acid added in the recovery step (B) to generate hydroxyl groups, and when a relatively large number of hydroxyl groups are contained, these large amounts of hydroxyl groups The deactivation step (A-2) is preferably performed before the recovery step (B), because it is believed that the condensation reaction between them is likely to occur.

Examples of reagents used for inactivating alkoxy groups and hydroxyl groups (hereinafter sometimes referred to as deactivating reagents) include methyllithium, ethyllithium, n-propyllithium, isopropyllithium, n-butyllithium, Alkyllithiums such as sec-butyllithium and t-butyllithium; Alkylsodiums such as methylsodium, ethylsodium, n-propylsodium, isopropylsodium, n-butylsodium, sec-butylsodium and t-butylsodium; Alkyl potassium such as potassium, ethyl potassium, n-propyl potassium, isopropyl potassium, n-butyl potassium, sec-butyl potassium, t-butyl potassium; methylmagnesium bromide, ethylmagnesium bromide, t-butylmagnesium bromide, t-butyl Alkyl magnesium halides such as magnesium chloride and sec-butyl magnesium iodide; Dialkyl copper lithiums such as dimethyl copper lithium, diethyl copper lithium, methyl ethyl copper lithium, methyl n-propyl copper lithium, and ethyl n-butyl copper lithium ; lithium amides such as lithium diisopropylamide, lithium diisoethylamide, lithium di-t-butylamide; and Lewis bases. Among these, n-butyllithium, sec-butyllithium, methyllithium, methylmagnesium bromide, and dimethylcopperlithium are preferred, since steric hindrance should be small in order to rapidly progress the deactivation reaction.

Amount of deactivating reagent used in step (A-2)/molar ratio of total amount of alkoxy groups and hydroxyl groups derived from group V contained in the conjugated diene-based graft polymer obtained in step (A-1) is preferably 0.5 or more, more preferably 1.0 or more, and even more preferably 2.0 or more. Also, it is preferably 100 or less, more preferably 50 or less, and even more preferably 20 or less. If the amount of the deactivating reagent is small, the number of functional groups (c) directly bonded to the branch point cannot be adjusted within the desired range. tends to get worse.

The inactivation reaction in the step (A-2) is usually carried out at a temperature of 0 to 100° C. for 0.1 to 50 hours. The deactivating reagent may be diluted before use, and the solvent for dilution is not particularly limited as long as it is inert to the deactivating reagent and does not adversely affect the reaction. Examples include hexane, cyclohexane, heptane, octane, Saturated aliphatic hydrocarbons or aromatic hydrocarbons such as decane, toluene, benzene, and xylene can be mentioned. In addition, a Lewis base may be added as an additive during the deactivation reaction. Lewis bases include, for example, ethers such as dimethyl ether, diethyl ether and tetrahydrofuran; glycol ethers such as ethylene glycol dimethyl ether and diethylene glycol dimethyl ether. amines such as triethylamine, N,N,N',N'-tetramethylethylenediamine and N-methylmorpholine; These Lewis bases may be used singly or in combination of two or more.

The deactivation reaction can be carried out until the number of functional groups (c) directly bonded to the branch point reaches a desired range. After that, the inactivating reagent can be deactivated by adding a polymerization terminator such as methanol or isopropanol.

[Step (B)]
The method for producing a conjugated diene-based graft polymer of the present invention comprises:
(B) a step of recovering the obtained conjugated diene-based graft polymer;
including.

In step (B), the obtained conjugated diene-based graft polymer of the present invention is recovered. The method for recovering the conjugated diene-based graft polymer is not particularly limited. The resulting solution is poured into a poor solvent such as methanol to precipitate the conjugated diene-based graft polymer, or the polymerization reaction solution is washed with water, separated, and dried to isolate the conjugated diene-based graft polymer. can be recovered by

[Polymer composition]
The polymer composition of the present invention contains the conjugated diene-based graft polymer of the present invention (hereinafter also referred to as conjugated diene-based graft polymer (α)). The polymer composition may further contain a polymer (β) other than the conjugated diene-based graft polymer (α). The other polymer (β) may be a thermoplastic polymer (β1) or a curable polymer (β2).

Examples of the thermoplastic polymer (β1) include acrylic resins such as polymethyl methacrylate and (meth)acrylic acid ester polymers or copolymers; polyethylene, ethylene-vinyl acetate copolymer, polypropylene, polybutene- 1, poly-4-methylpentene-1, olefin resins such as polynorbornene; ethylene ionomer; polystyrene, styrene-maleic anhydride copolymer, high impact polystyrene, AS resin, ABS resin, AES resin, AAS resin, Styrene resins such as ACS resin and MBS resin; Styrene-methyl methacrylate copolymer; Styrene-methyl methacrylate-maleic anhydride copolymer; Polyester resins such as polyethylene terephthalate, polybutylene terephthalate and polylactic acid; Nylon 6, Polyamides such as nylon 66, polyamide elastomer; Polycarbonate; Polyvinyl chloride; Polyvinylidene chloride; Polyvinyl alcohol; Ethylene-vinyl alcohol copolymer; Polyacetal; acrylic rubbers; silicone rubbers; styrene thermoplastic elastomers such as SEPS, SEBS and SIS; and olefin rubbers such as IR, EPR and EPDM.

Examples of the curable polymer (β2) include epoxy resins, unsaturated polyester resins, epoxy (meth)acrylate resins, ester (meth)acrylate resins, phenol resins, urea resins, melamine resins, thermosetting urethane resins, silicon Resins, imide resins, furan resins, alkyd resins, allyl resins, diallyl phthalate resins. Among these, from the viewpoint of availability and basic physical properties of the cured product, and from the viewpoint of obtaining a polymer composition that is more excellent due to the ability to release air bubbles and the toughness of the cured product obtained, epoxy resins, unsaturated polyesters Resins and epoxy (meth)acrylate resins are preferred, among which epoxy resins and unsaturated polyester resins are more preferred, and epoxy resins are even more preferred. The curable polymer (β2) may be used singly or in combination of two or more.

When the polymer composition contains a conjugated diene-based graft polymer (α) and another polymer (β), the mass ratio of the conjugated diene-based graft polymer (α) to the other polymer (β) (α)/(β) is preferably 1/99 to 99/1.

Moreover, various additives may be added to the polymer composition of the present invention to the extent that the effects of the present invention are not impaired. For example, when the other polymer (β) is a thermoplastic polymer (β1), such additives include reinforcing agents or fillers such as calcium carbonate, silica, carbon black, glass fiber, clay, process oil, , polyethylene glycol, glycerin, phthalates, and other plasticizers can be used as additives. Other additives include, for example, heat stabilizers, antioxidants, ultraviolet absorbers, colorants, pigments, lubricants, and surfactants. Furthermore, the additive includes a foaming agent, and a foam can be produced from a polymer composition containing the foaming agent and the thermoplastic polymer (β1).
For example, when the other polymer (β) is a curable polymer (β2), such additives include curing agents, curing accelerators, known rubbers, thermoplastic elastomers, impact modifiers such as core-shell particles, etc. agents, fillers (silica, talc, calcium carbonate, inorganic particles such as aluminum hydroxide, etc.), flame retardants, antifoaming agents, pigments, dyes, antioxidants, weathering agents, lubricants, release agents, and the like.

The polymer composition of the present invention can be prepared by a conventional method of mixing polymeric substances depending on the composition ratio of each component such as the conjugated diene graft polymer (α) and the other polymer (β).

When the other polymer (β) is a thermoplastic polymer (β1), the polymer composition can be produced using a mixing device such as an extruder, mixing roll, Banbury mixer, kneader, or the like. In particular, in the present invention, a method of melt-kneading using these mixing apparatuses is a preferred embodiment.

When the other polymer (β) is a curable polymer (β2), for example, the polymer composition is obtained by thoroughly mixing with a mixer, melt-kneading with a mixing roll, an extruder, or the like, then cooling and pulverizing. can be made.

The polymer composition of the present invention can be molded into articles by various conventionally known molding methods.

When the other polymer (β) is a thermoplastic polymer (β1), the polymer composition is molded by, for example, extrusion molding, injection molding, blow molding, compression molding, vacuum molding, calender molding, etc. products can be produced. Molded articles, sheets, films and the like of various shapes can be obtained by these methods. In addition, non-woven fabrics and fibrous molded articles can also be produced by methods such as melt blowing and spunbonding.

When the other polymer (β) is the curable polymer (β2), the polymer composition can be thermally cured by, for example, a transfer molding method to produce a molded product. Other molding methods when the polymer composition contains the curable polymer (β2) include, for example, injection molding and compression molding.

When the other polymer (β) is a thermoplastic polymer (β1), the uses of molded articles obtained from the polymer composition include, for example, automobile interior and exterior parts such as bumpers and instrument panels, televisions, stereos, and cleaners. Housing materials for home appliances such as machines, electrical and electronic parts such as connectors, materials for electric cables, meat and fish trays, fruit and vegetable packs, frozen food containers and other food packaging materials or food containers, industrial materials and other packaging materials, sports Sporting goods such as shoe materials, fabric or leather products, toys, sandals and other daily goods, various films, sheets, laminated materials for molded products, adhesives and adhesives, elastic materials used for paper diapers, hoses, tubes, belts and various rubber products, medical supplies, and the like.

When the other polymer (β) is a curable polymer (β2), applications of the polymer composition, its cured product or molded article include, for example, adhesives for fiber-reinforced composite materials (fiber-reinforced composite materials for concrete Adhesives for fiber reinforced composite materials for transportation equipment such as automobiles, railway vehicles and aircraft, adhesives for fiber reinforced composite materials for various sporting goods, etc.), adhesives for assembly (transportation such as automobiles, railway vehicles and aircraft Adhesives for assembling parts in transportation equipment, etc.); various paints such as anti-corrosion and waterproof paints for water supply and sewage, anti-corrosion paints for metals; Various coating primers such as coating primers; Various lining materials such as metal lining materials, concrete lining materials, and tank lining materials; Various repair materials such as concrete crack repair materials; Printed wiring boards, insulating boards, semiconductor sealing Examples include various electric and electronic parts such as sealing materials and packaging materials.

EXAMPLES The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to these Examples. In the following examples and comparative examples, physical properties of conjugated diene-based graft polymers were evaluated by the following methods.

(1) Weight average molecular weight (Mw), number average molecular weight (Mn), molecular weight distribution (Mw/Mn)
By gel permeation chromatography (GPC), the conjugated diene-based graft polymer and the weight average molecular weight (Mw), number average molecular weight (Mn), and molecular weight distribution (Mw/Mn) of the polymer at each stage of its production were measured. Calculated in terms of standard polystyrene.
Apparatus: GPC apparatus "HLC-8220" manufactured by Tosoh Corporation
Separation column: Tosoh Corporation "TSKgel SuperMultiporeHZ-M (column diameter = 4.6 mm, column length = 15 cm)" (used by connecting two in series)
Eluent: Tetrahydrofuran Eluent flow rate: 0.35 mL/min Column temperature: 40°C
Detection method: Differential refractive index (RI)
Injection volume: 10 μl
Concentration: 1 mg/1 cc (conjugated diene-based graft polymer/THF)

(2) Vinyl content, styrene unit content
By ¹ H-NMR, the conjugated diene-based graft polymer and the vinyl content and styrene unit content of the polymer at each stage of its production were calculated. The vinyl content was calculated from the area ratio of the peak of the double bond derived from the vinylated conjugated diene unit in the obtained spectrum and the peak of the double bond derived from the non-vinylated conjugated diene unit. The styrene unit content was calculated from the area ratio of the peak of the derived aromatic ring and the peak of the double bond derived from the conjugated diene unit.
Apparatus: Nuclear magnetic resonance apparatus "JNM-ECX400" manufactured by JEOL Ltd.
Solvent: Heavy chloroform Measurement temperature: 50°C
Accumulated times: 1024 times

(3) Average number Y of Si atoms (branching points) per molecule of polymer
The average number Y of Si atoms (branch points) per molecule of the conjugated diene-based graft polymer and the functional group-modified conjugated diene-based polymer (F) was measured by an inductively coupled plasma mass spectrometer (ICP-MS). Using the Si content (mass %) of coalescence and the number average molecular weight (Mn) in terms of standard polystyrene, it is determined by the following formula.
(Number of Si atoms per molecule of polymer) = [(Si content (mass%)) / 100] x [(number average molecular weight Mn) / (molecular weight of styrene unit) x (conjugated diene and optionally included (Average molecular weight of monomer units other than conjugated diene used)]/atomic weight of Si With regard to Example 16, the average number Y of B atoms (branching points) per polymer molecule was determined in the same manner.

(4) Average number (X/Y) of functional groups (c) per Si atom (branching point) contained in the conjugated diene-based graft polymer
The average number (X/Y) of functional groups (c) (at least one selected from the group consisting of alkoxy groups and hydroxyl groups) per Si atom (branching point) contained in the conjugated diene-based graft polymer is It is obtained from the result of ²⁹ Si-NMR measurement of the graft polymer. Specifically, the integrated values of Si bonded with one functional group (c), Si bonded with two functional groups (c), and the like multiplied by the number of functional groups are summed, and the integral Calculated by comparing with a simple sum of the values.
Regarding Example 16, by measuring ¹¹ B-NMR, the average number (X/Y) of functional groups (c) per B atom (branching point) contained in the conjugated diene-based graft polymer was determined by the same method. asked for

(5) Average number X of functional groups (c) per molecule of conjugated diene-based graft polymer
The average number X of the functional groups (c) per molecule of the conjugated diene-based graft polymer is the average number of functional groups (c) per Si atom (branch point) contained in the conjugated diene-based graft polymer and the conjugated diene It is obtained from the following formula using the average number of Si atoms per molecule of the system graft polymer.
(Average number X of functional groups (c) per molecule of conjugated diene-based graft polymer)=(Average number of functional groups (c) per Si atom (branch point) contained in conjugated diene-based graft polymer) x (Average number of Si atoms per molecule of conjugated diene-based graft polymer)
Regarding Example 16, the average number of functional groups (c) per B atom (branch point) contained in the conjugated diene graft polymer and the average number of B atoms per molecule of the conjugated diene graft polymer were used. Then, the average number X of the functional groups (c) per molecule of the conjugated diene-based graft polymer was determined.

(6) Average number W of side chains (b) per molecule of conjugated diene-based graft polymer
The average number W of the side chains (b) per molecule of the conjugated diene graft polymer is determined by the active terminal polymer ( Using the amount (number of moles) charged per active terminal of I) and the amount (number of moles) charged (number of moles) of the functional group-modified conjugated diene polymer (F), it is determined by the following formula.
(Average number W of side chains (b) per molecule of conjugated diene-based graft polymer) = (Amount charged per active end of active terminal polymer (I) as a constituent of side chain (b) (number of moles ))/(Feeding amount (number of moles) of functional group-modified conjugated diene-based polymer (F))

(7) Average number of side chains (b) per Si atom (branching point) contained in the conjugated diene-based graft polymer (W/Y)
The average number (W/Y) of side chains (b) per Si atom (branch point) contained in the conjugated diene graft polymer is the average number of side chains (b) per molecule of the conjugated diene graft polymer. Using the number W and the average number Y of Si atoms per molecule of the conjugated diene-based graft polymer, it is obtained from the following formula.
(Average number of side chains (b) per Si atom contained in the conjugated diene-based graft polymer (W/Y)) = (Average number of side chains (b) per molecule of the conjugated diene-based graft polymer W) / (average number Y of Si atoms per molecule of conjugated diene-based graft polymer)
Regarding Example 16, the average number W of the side chains (b) per molecule of the conjugated diene-based graft polymer and the average number Y of B atoms per molecule of the conjugated diene-based graft polymer were used to obtain the conjugated diene-based The average number (W/Y) of side chains (b) per B atom (branching point) contained in the graft polymer was determined.

(8) Coupling Rate The coupling rate of the conjugated diene-based graft polymer is obtained from the following formula using the peak area of the uncoupling polymer component obtained by the GPC measurement and the total sum of all peak areas.
(Coupling rate (%)) = [{((sum of all peak areas) - (peak area of component derived from active terminal polymer (I))}/(sum of all peak areas)] x 100

(9) Stability The stability of the conjugated diene-based graft polymer was evaluated by the property change in the step of drying the polymer solution containing the conjugated diene-based graft polymer after washing (step (5) below). A 100-fold amount of cyclohexane was added to the polymer that had been vacuum-dried at 70° C. for 24 hours, and the mixture was shaken at room temperature for 12 hours. The mass of the charged polymer was M1, and the mass of the insoluble matter after filtration and drying was M2.
(Gel fraction (%)) = (M2/M1) x 100
A: Gel fraction after drying is less than 50% by mass B: Gel fraction after drying is 50% by mass or more

(10) Condensation reactivity The affinity of the conjugated diene-based graft polymer with the polar material was evaluated by the condensation reactivity of the alkoxysilane group under acidic conditions. A conjugated diene-based graft polymer was dissolved in cyclohexane so that the solid content concentration was 10% by mass, mixed with a 1% by mass acetic acid aqueous solution at a weight ratio of 1:1, shaken at room temperature for 12 hours, and then insoluble (gel). It was visually confirmed whether or not there was any generation of , and the condensation reactivity was evaluated according to the following indices. It can be said that condensation reactivity is higher when insoluble matter is present, and affinity with polar materials is higher.
A: With insoluble matter B: No insoluble matter

[Example 1]
(Step (1))
A sufficiently dried 5 L autoclave is purged with nitrogen, charged with 1580 g of cyclohexane and 56 g of sec-butyllithium (10.5% by mass cyclohexane solution), heated to 50°C, and then brought to a polymerization temperature of 50°C under stirring conditions. 2.9 g of tetrahydrofuran and 1250 g of butadiene were successively added while controlling as above, and polymerized for 1 hour. After that, 3.3 g of methanol was added to terminate the polymerization reaction to obtain a polymer solution. Water was added to the obtained polymer solution and stirred, and the polymer solution was washed with water. After finishing the stirring and confirming that the polymer solution phase and the water phase were separated, the water was separated. The unmodified conjugated diene polymer (F'-1) was obtained by vacuum-drying the polymer solution after washing at 70° C. for 24 hours.

(Step (2))
Subsequently, 700 g of the unmodified conjugated diene polymer (F'-1) obtained in step (1) was charged into a 1-liter autoclave, and the mixture was degassed with nitrogen while stirring at 60° C. for 3 hours. 0.9 g of t-butyl peroxypivalate and 51 g of 3-mercaptopropyltriethoxysilane were added and reacted at 80° C. for 8 hours to obtain a functional group-modified conjugated diene polymer (F-1). Analysis of the resulting functional group-modified conjugated diene polymer (F-1) revealed the weight average molecular weight, vinyl content, and styrene unit content of the main chain (a) of the conjugated diene graft polymer (G-1) described later. You can ask for the quantity. The resulting functional group-modified conjugated diene polymer (F-1) had a weight average molecular weight of 26,000, a vinyl content of 30 mol%, a styrene unit content of 0% by mass, and a Si atom content per molecule of the polymer. The average number was four. 1750 g of cyclohexane was added to the obtained functional group-modified conjugated diene polymer (F-1) to dilute it to a concentration of 30% by mass, and the functional group-modified conjugated diene polymer (F-1) used in the coupling reaction described later was obtained. ) was obtained.

(Step (3))
A sufficiently dried 5 L autoclave was purged with nitrogen, charged with 700 g of cyclohexane and 78 g of sec-butyllithium (10.5% by mass cyclohexane solution), heated to 50°C, and then brought to a polymerization temperature of 50°C under stirring conditions. While controlling as above, 340 g of butadiene was successively added and polymerized for 1 hour to obtain an active terminal polymer (I-1). By sampling and analyzing the polymer solution in step (3), the weight average molecular weight, vinyl content, and styrene unit content of the side chain (b) of the conjugated diene graft polymer (G-1) described later are determined. be able to. The obtained active terminal polymer (I-1) had a weight average molecular weight of 5,000, a vinyl content of 10 mol % and a styrene unit content of 0 mass %.

(Step (4))
Subsequently, 7.0 g of tetrahydrofuran and the functional group-modified conjugated diene polymer (F-1) obtained in step (2) were added to the solution containing the active terminal polymer (I-1) obtained in step (3). 1480 g of diluted solution was added and the coupling reaction was carried out at 50° C. for 2 hours. After that, 190 g of sec-butyllithium (10.5% by mass cyclohexane solution) was added and reacted for 6 hours to block some of the remaining alkoxy groups. After that, 21 g of methanol was added to terminate the polymerization reaction to obtain a polymer solution.

(Step (5))
Water was added to the obtained polymer solution and stirred, and the polymer solution was washed with water. After finishing the stirring and confirming that the polymer solution phase and the water phase were separated, the water was separated. After washing, the polymer solution was vacuum-dried at 70° C. for 24 hours to obtain a conjugated diene-based graft polymer (G-1). The resulting conjugated diene-based graft polymer (G-1) had a weight average molecular weight of 46,000, Mw/Mn of 1.5, a styrene unit content of 0% by mass, a coupling rate of 95%. The average number of Si atoms (branching points) per molecule is 4, the average number of functional groups (c) per polymer molecule is 0.4, and the number of functional groups (c) per Si atom (branching point) is The average number was 0.1, the average number of side chains (b) per polymer molecule was 4, and the average number of side chains (b) per Si atom (branch point) was 1. Table 1 shows the type and amount of each reagent used in Example 1, and Table 3 shows the molecular specifications and physical properties of the resulting conjugated diene-based graft polymer (G-1).

[Examples 2 to 14]
Conjugated diene-based graft polymer (G -2) to (G-14) were obtained. Tables 3 and 4 show the molecular specifications and physical properties of the obtained conjugated diene-based graft polymers (G-2) to (G-14).

[Example 15]
(Step (1))
A sufficiently dried 5 L autoclave is purged with nitrogen, charged with 1580 g of cyclohexane and 56 g of sec-butyllithium (10.5% by mass cyclohexane solution), heated to 50°C, and then brought to a polymerization temperature of 50°C under stirring conditions. 2.9 g of tetrahydrofuran and 1250 g of butadiene were successively added while controlling as above, and polymerized for 1 hour. After that, 3.3 g of methanol was added to terminate the polymerization reaction to obtain a polymer solution. Water was added to the obtained polymer solution and stirred, and the polymer solution was washed with water. After finishing the stirring and confirming that the polymer solution phase and the water phase were separated, the water was separated. After washing, the polymer solution was vacuum-dried at 70° C. for 24 hours to obtain an unmodified conjugated diene polymer (F′-15).

(Step (2))
Subsequently, 700 g of the unmodified conjugated diene polymer (F'-15) obtained in step (1), 1400 g of toluene, A toluene solution of platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (2.1×10 ⁻⁵ mol as platinum atom) and 0.12 g of acetic acid were charged. Into this, 34 g of triethoxysilane was added dropwise at an internal temperature of 75 to 85° C. over 2 hours, and then stirred at 80° C. for 1 hour. After completion of stirring, the mixture was concentrated under reduced pressure and filtered to obtain a functional group-modified conjugated diene polymer (F-15). Analysis of the resulting functional group-modified conjugated diene polymer (F-15) revealed the weight average molecular weight, vinyl content, and styrene unit content of the main chain (a) of the conjugated diene graft polymer (G-15) described later. You can ask for the quantity. The resulting functional group-modified conjugated diene polymer (F-15) had a weight average molecular weight of 26,000, a vinyl content of 30 mol%, a styrene unit content of 0% by mass, and a Si atom content per molecule of the polymer. The average number was four. 1710 g of cyclohexane was added to the obtained functional group-modified conjugated diene polymer (F-15) to dilute it to a concentration of 30% by mass, and the functional group-modified conjugated diene polymer (F-15) used in the coupling reaction described later was obtained. ) was obtained.

(Step (3))
A sufficiently dried 5 L autoclave was purged with nitrogen, charged with 700 g of cyclohexane and 78 g of sec-butyllithium (10.5% by mass cyclohexane solution), heated to 50°C, and then brought to a polymerization temperature of 50°C under stirring conditions. While controlling as above, 340 g of butadiene was successively added and polymerized for 1 hour to obtain an active terminal polymer (I-15). By sampling and analyzing the polymer solution in step (3), the weight average molecular weight, vinyl content, and styrene unit content of the side chain (b) of the conjugated diene graft polymer (G-15) described later are determined. be able to. The obtained active terminal polymer (I-15) had a weight average molecular weight of 5,000, a vinyl content of 10 mol % and a styrene unit content of 0 mass %.

(Step (4))
Subsequently, 7.0 g of tetrahydrofuran and the functional group-modified conjugated diene polymer (F-15) obtained in step (2) were added to the solution containing the active terminal polymer (I-15) obtained in step (3). 1480 g of diluted solution was added and the coupling reaction was carried out at 50° C. for 2 hours. After that, 195 g of sec-butyllithium (10.5% by mass cyclohexane solution) was added and reacted for 6 hours to block some of the remaining alkoxy groups. After that, 21 g of methanol was added to terminate the polymerization reaction to obtain a polymer solution.

(Step (5))
Water was added to the obtained polymer solution and stirred, and the polymer solution was washed with water. After finishing the stirring and confirming that the polymer solution phase and the water phase were separated, the water was separated. After washing, the polymer solution was vacuum-dried at 70° C. for 24 hours to obtain a conjugated diene-based graft polymer (G-15). The resulting conjugated diene-based graft polymer (G-15) had a weight average molecular weight of 46,000, Mw/Mn of 1.5, a styrene unit content of 0% by mass, and a coupling rate of 95%. The average number of Si atoms (branching points) per molecule is 4, the average number of functional groups (c) per polymer molecule is 0.4, and the number of functional groups (c) per Si atom (branching point) is The average number was 0.1, the average number of side chains (b) per polymer molecule was 4, and the average number of side chains (b) per Si atom (branching point) was 1. Table 4 shows the molecular specifications and physical properties of the resulting conjugated diene-based graft polymer (G-15).

[Example 16]
(Step (1))
A sufficiently dried 5 L autoclave is purged with nitrogen, charged with 1580 g of cyclohexane and 56 g of sec-butyllithium (10.5% by mass cyclohexane solution), heated to 50°C, and then brought to a polymerization temperature of 50°C under stirring conditions. 2.9 g of tetrahydrofuran and 1250 g of butadiene were successively added while controlling as above, and polymerized for 1 hour. After that, 3.3 g of methanol was added to terminate the polymerization reaction to obtain a polymer solution. Water was added to the obtained polymer solution and stirred, and the polymer solution was washed with water. After finishing the stirring and confirming that the polymer solution phase and the water phase were separated, the water was separated. After washing, the polymer solution was vacuum-dried at 70° C. for 24 hours to obtain an unmodified conjugated diene polymer (F′-16).

(Step (2))
Subsequently, in a 5 L separable flask equipped with a stirrer, a reflux condenser, a dropping funnel and a thermometer, 700 g of the unmodified conjugated diene polymer (F'-16) obtained in step (1) and 1400 g of cyclohexane were added. Preparation and nitrogen substitution were performed. 22 g of trimethyl borate and 1.8 g of triethylamine borane were added thereto and reacted at 80° C. for 10 hours. After completion of the reaction, the mixture was concentrated under reduced pressure and filtered to obtain a functional group-modified conjugated diene polymer (F-16). Analysis of the resulting functional group-modified conjugated diene polymer (F-16) revealed the weight average molecular weight, vinyl content, and styrene unit content of the main chain (a) of the conjugated diene graft polymer (G-16) described later. You can ask for the quantity. The obtained functional group-modified conjugated diene polymer (F-16) had a weight average molecular weight of 26,000, a vinyl content of 30 mol%, a styrene unit content of 0% by mass, and a B atom per molecule of the polymer. The average number was four. 1680 g of cyclohexane was added to the obtained functional group-modified conjugated diene polymer (F-16) to dilute it to a concentration of 30% by mass, and the functional group-modified conjugated diene polymer (F-16) used in the coupling reaction described later was obtained. ) was obtained.

(Step (3))
A sufficiently dried 5 L autoclave was purged with nitrogen, charged with 700 g of cyclohexane and 78 g of sec-butyllithium (10.5% by mass cyclohexane solution), heated to 50°C, and then brought to a polymerization temperature of 50°C under stirring conditions. While controlling as above, 340 g of butadiene was added successively and polymerized for 1 hour to obtain an active terminal polymer (I-16). By sampling and analyzing the polymer solution in step (3), the weight average molecular weight, vinyl content, and styrene unit content of the side chain (b) of the conjugated diene graft polymer (G-16) described later are determined. be able to. The obtained active terminal polymer (I-16) had a weight average molecular weight of 5,000, a vinyl content of 10 mol % and a styrene unit content of 0 mass %.

(Step (4))
Subsequently, 7.0 g of tetrahydrofuran and the functional group-modified conjugated diene polymer (F-16) obtained in step (2) were added to the solution containing the active terminal polymer (I-16) obtained in step (3). 1480 g of diluted solution was added and the coupling reaction was carried out at 50° C. for 2 hours. After that, 195 g of sec-butyllithium (10.5% by mass cyclohexane solution) was added and reacted for 6 hours to block some of the remaining alkoxy groups. After that, 21 g of methanol was added to terminate the polymerization reaction to obtain a polymer solution.

(Step (5))
Water was added to the obtained polymer solution and stirred, and the polymer solution was washed with water. After finishing the stirring and confirming that the polymer solution phase and the water phase were separated, the water was separated. After washing, the polymer solution was vacuum-dried at 70° C. for 24 hours to obtain a conjugated diene-based graft polymer (G-16). The resulting conjugated diene-based graft polymer (G-16) had a weight average molecular weight of 46,000, Mw/Mn of 1.5, a styrene unit content of 0% by mass, and a coupling rate of 95%. The average number of B atoms (branching points) per molecule is 4, the average number of functional groups (c) per polymer molecule is 0.4, and the number of functional groups (c) per B atom (branching point) is The average number was 0.1, the average number of side chains (b) per polymer molecule was 4, and the average number of side chains (b) per B atom (branching point) was 1. Table 4 shows the molecular specifications and physical properties of the obtained conjugated diene-based graft polymer (G-16).

[Comparative Example 1]
(Step (1))
A sufficiently dried 5 L autoclave is purged with nitrogen, charged with 1580 g of cyclohexane and 56 g of sec-butyllithium (10.5% by mass cyclohexane solution), heated to 50°C, and then brought to a polymerization temperature of 50°C under stirring conditions. 2.9 g of tetrahydrofuran and 1250 g of butadiene were successively added while controlling as above, and polymerized for 1 hour. After that, 3.3 g of methanol was added to terminate the polymerization reaction to obtain a polymer solution. Water was added to the obtained polymer solution and stirred, and the polymer solution was washed with water. After finishing the stirring and confirming that the polymer solution phase and the water phase were separated, the water was separated. After washing, the polymer solution was vacuum-dried at 70° C. for 24 hours to obtain an unmodified conjugated diene polymer (F′-17).

(Step (2))
Subsequently, 700 g of the unmodified conjugated diene-based polymer (F'-18) obtained in step (1), 1400 g of cyclohexane, 5.6 mL of a 2% xylene solution of a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (“PC072” manufactured by Petrarch System) and 120 g of trimethylchlorosilane were added and these were mixed overnight. Stirred. Thereafter, 20 g of dimethylchlorosilane was added dropwise into the mixture, and the mixture was gradually heated until the internal temperature reached 70°C, and stirred under reflux for 24 hours while maintaining the internal temperature at 70°C. After completion of stirring, the mixture was concentrated under reduced pressure and filtered to obtain a functional group-modified conjugated diene polymer (F-17). Analysis of the resulting functional group-modified conjugated diene polymer (F-17) revealed the weight average molecular weight, vinyl content, and styrene unit content of the main chain (a) of the conjugated diene graft polymer (G-17) described later. You can ask for the quantity. The resulting functional group-modified conjugated diene polymer (F-17) had a weight average molecular weight of 26,000, a vinyl content of 30 mol%, a styrene unit content of 0% by mass, and a Si atom content per molecule of the polymer. The average number was four. 1680 g of cyclohexane was added to the obtained functional group-modified conjugated diene-based polymer (F-17) to dilute it to a concentration of 30% by mass, and the functional group-modified conjugated diene-based polymer (F-17) used in the coupling reaction described later was obtained. ) was obtained.

(Step (3))
A sufficiently dried 5 L autoclave was purged with nitrogen, charged with 700 g of cyclohexane and 78 g of sec-butyllithium (10.5% by mass cyclohexane solution), heated to 50°C, and then brought to a polymerization temperature of 50°C under stirring conditions. While controlling as above, 340 g of butadiene was successively added and polymerized for 1 hour to obtain an active terminal polymer (I-17). By sampling and analyzing the polymer solution in step (3), the weight average molecular weight, vinyl content, and styrene unit content of the side chain (b) of the conjugated diene graft polymer (G-17) described later are determined. be able to. The obtained active terminal polymer (I-17) had a weight average molecular weight of 5,000, a vinyl content of 10 mol % and a styrene unit content of 0 mass %.

(Step (4))
Subsequently, 7.0 g of tetrahydrofuran and the functional group-modified conjugated diene polymer (F-17) obtained in step (2) were added to the solution containing the active terminal polymer (I-17) obtained in step (3). 1480 g of diluted solution was added and the coupling reaction was carried out at 50° C. for 2 hours. After that, 195 g of sec-butyllithium (10.5 mass % cyclohexane solution) was added and reacted for 6 hours. After that, 21 g of methanol was added to terminate the polymerization reaction to obtain a polymer solution.

(Step (5))
Water was added to the obtained polymer solution and stirred, and the polymer solution was washed with water. After finishing the stirring and confirming that the polymer solution phase and the water phase were separated, the water was separated. After washing, the polymer solution was vacuum-dried at 70° C. for 24 hours to obtain a conjugated diene-based graft polymer (G-17). The resulting conjugated diene-based graft polymer (G-17) had a weight average molecular weight of 46,000, Mw/Mn of 1.5, a styrene unit content of 0% by mass, a coupling rate of 99%. The average number of Si atoms (branching points) per molecule is 4, the average number of functional groups (c) per polymer molecule is 0, and the average number of functional groups (c) per Si atom (branching points) was 0, the average number of side chains (b) per polymer molecule was 4, and the average number of side chains (b) per Si atom (branching point) was 1. Table 4 shows the molecular specifications and physical properties of the obtained conjugated diene-based graft polymer (G-17).

[Comparative Example 2]
(Step (1))
A sufficiently dried 5 L autoclave is purged with nitrogen, charged with 1580 g of cyclohexane and 56 g of sec-butyllithium (10.5% by mass cyclohexane solution), heated to 50°C, and then brought to a polymerization temperature of 50°C under stirring conditions. 2.9 g of tetrahydrofuran and 1250 g of butadiene were successively added while controlling as above, and polymerized for 1 hour. After that, 3.3 g of methanol was added to terminate the polymerization reaction to obtain a polymer solution. Water was added to the obtained polymer solution and stirred, and the polymer solution was washed with water. After finishing the stirring and confirming that the polymer solution phase and the water phase were separated, the water was separated. After washing, the polymer solution was vacuum-dried at 70° C. for 24 hours to obtain an unmodified conjugated diene polymer (F′-18).

(Step (2))
Subsequently, 700 g of the unmodified conjugated diene polymer (F'-18) obtained in step (1) was charged into a 1 L autoclave, and the mixture was degassed with nitrogen while stirring at 60° C. for 3 hours. 0.9 g of t-butyl peroxypivalate and 51 g of 3-mercaptopropyltriethoxysilane were added and reacted at 80° C. for 8 hours to obtain a functional group-modified conjugated diene polymer (F-18). Analysis of the resulting functional group-modified conjugated diene polymer (F-18) revealed the weight average molecular weight, vinyl content, and styrene unit content of the main chain (a) of the conjugated diene graft polymer (G-18) described later. You can ask for the quantity. The obtained functional group-modified conjugated diene polymer (F-18) had a weight average molecular weight of 26,000, a vinyl content of 30 mol%, a styrene unit content of 0% by mass, and a Si atom content per molecule of the polymer. The average number was four. 1750 g of cyclohexane was added to the obtained functional group-modified conjugated diene polymer (F-18) to dilute it to a concentration of 30% by mass, and the functional group-modified conjugated diene polymer (F-18) used in the coupling reaction described later was obtained. ) was obtained.

(Step (3))
A sufficiently dried 5 L autoclave was purged with nitrogen, charged with 700 g of cyclohexane and 78 g of sec-butyllithium (10.5% by mass cyclohexane solution), heated to 50°C, and then brought to a polymerization temperature of 50°C under stirring conditions. While controlling as above, 340 g of butadiene was successively added and polymerized for 1 hour to obtain an active terminal polymer (I-18). By sampling and analyzing the polymer solution in step (3), the weight average molecular weight, vinyl content, and styrene unit content of the side chain (b) of the conjugated diene graft polymer (G-18) described later are determined. be able to. The obtained active terminal polymer (I-18) had a weight average molecular weight of 5,000, a vinyl content of 10 mol % and a styrene unit content of 0 mass %.

(Step (4))
Subsequently, 7.0 g of tetrahydrofuran and the functional group-modified conjugated diene polymer (F-18) obtained in step (2) were diluted in the solution containing the active terminal polymer (I-18) obtained in step (3). 1480 g of the solution was added and the coupling reaction was allowed to proceed at 50° C. for 2 hours. After that, 10 g of methanol was added to terminate the polymerization reaction to obtain a polymer solution.

(Step (5))
Water was added to the obtained polymer solution and stirred, and the polymer solution was washed with water. After finishing the stirring and confirming that the polymer solution phase and the water phase were separated, the water was separated. After washing, the polymer solution was vacuum-dried at 70° C. for 24 hours. The resulting conjugated diene-based graft polymer (G-18) had a weight average molecular weight of 46,000, Mw/Mn of 1.5, a styrene unit content of 0% by mass, a coupling ratio of 95%. The average number of Si atoms (branching points) per molecule is 4, the average number of functional groups (c) per polymer molecule is 8, and the average number of functional groups (c) per Si atom (branching points) was 1.0, the average number of side chains (b) per polymer molecule was 4, and the average number of side chains (b) per Si atom (branching point) was 1 (weight average molecular weight , Mw/Mn, vinyl content, styrene unit content, average number of Si atoms (branching points) per polymer molecule, average number of functional groups (c) per polymer molecule, Si atoms (branching points) The average number per unit is a value obtained by measuring the polymer obtained by drying the polymer solution obtained in step (4) at normal temperature and normal pressure). Table 4 shows the molecular specifications and physical properties of the obtained conjugated diene-based graft polymer (G-18).

The types and amounts of each reagent used in steps (1) to (5) in Examples 1 to 14 are shown in Tables 1 and 2 below, and the conjugated diene systems obtained in Examples 1 to 16 and Comparative Examples 1 and 2 The physical properties of the graft polymer are shown in Tables 3 and 4.

In Tables 1 and 2, abbreviations indicate the following respectively SBL: sec-butyllithium THF: tetrahydrofuran t-BPOP: t-butyl peroxypivalate Bd: 1,3-butadiene Ip: isoprene St: styrene MPTES: (3- Mercaptopropyl)triethoxysilane MPTMS: (3-mercaptopropyl)trimethoxysilane

From Tables 3 and 4, the average number (X/Y) of functional groups (c) per Si atom (branching point) is in the range of 0<(X/Y)<1. Conjugated diene systems of Examples 1 to 16 Since the graft polymer has high condensation reactivity, it can be seen that it has excellent affinity with polar materials. Furthermore, the polymer solution containing the conjugated diene-based graft polymer has a low ratio of insoluble matter in the step of drying the polymer solution after washing, indicating high stability.
On the other hand, the conjugated diene-based graft polymer of Comparative Example 1, in which the average number (X/Y) of the functional groups (c) per Si atom (branching point) is 0, has low condensation reactivity, and is therefore suitable as a polar material. Inferior affinity with Further, the conjugated diene-based graft polymer of Comparative Example 2, in which the average number (X/Y) of the functional groups (c) per Si atom (branching point) is in the range of 1<(X/Y), is obtained from the polymer solution In the process of drying, the ratio of insoluble matter was large and it was difficult to take out.

The conjugated diene-based graft polymer of the present invention is excellent in affinity with polar materials and has high stability. It can be effectively used in a wide range of fields such as laminate materials, elastic materials, various rubber products, medical supplies, various adhesives, and various painting primers.

Claims (11)

In the main chain (a) made of a polymer containing a conjugated diene unit,
A side chain (b ) is a conjugated diene-based graft polymer in which
the main chain (a) is directly or through a linking chain bound to the branch point,
The side chain (b) is directly attached to the branch point,
the heteroatom is at least one selected from the group consisting of Si, Sn, Ge, Pb, P, B, and Al;
At least one of the branch points is directly bonded to at least one functional group (c) selected from the group consisting of an alkoxy group and a hydroxyl group,
The average number X of the functional groups (c) directly bonded to the branch points per molecule of the conjugated diene-based graft polymer and the average number Y of the branch points per molecule of the conjugated diene-based graft polymer are represented by the following formula (2);
0<(X/Y)<1 (2)
satisfy the relationship of
Conjugated diene graft polymer. The average number X of the functional groups (c) directly bonded to the branch points per molecule of the conjugated diene-based graft polymer is represented by the following formula (3);
0<X≦10 (3)
The conjugated diene-based graft polymer according to claim 1, which satisfies the relationship of 3. The conjugated diene-based graft polymer according to claim 1, wherein said heteroatom is Si. The average number W of side chains (b) directly bonded to the branch points per molecule of the conjugated diene-based graft polymer and the average number Y of branch points per molecule of the conjugated diene-based graft polymer are represented by the following formula (4);
0.5≦(W/Y) (4)
The conjugated diene-based graft polymer according to any one of claims 1 to 3, which satisfies the relationship of (A-1) Active terminal polymer represented by the following formula (I) and PX (I)
(In formula (I), P represents a polymer chain containing at least one monomer unit selected from the group consisting of conjugated diene units and aromatic vinyl compound units, and X represents an anionic polymerization active terminal.) ,
A step of reacting a functional group-modified conjugated diene-based polymer having a branched chain containing a functional group-containing portion represented by the following formula (II) to prepare a conjugated diene-based graft polymer.

(In formula (II), V represents an alkoxy group or a hydroxyl group, Z is Si, Sn, Ge, Pb, P, B, or Al, R ¹ is an aryl group having 6 to 12 carbon atoms, 1 to 12 alkyl groups or hydrogen atoms, N represents the valence of Z, n is an integer satisfying the following formula (5);
1≤n≤N-1 (5)
When n is 2 or more, V may be the same or different; when Nn is 2 or more, R ¹ may be the same or different; , Z may be the same or different. ); and (B) a step of recovering the obtained conjugated diene-based graft polymer;
The method for producing a conjugated diene-based graft polymer according to claim 1, comprising: Furthermore, before step (B),
(A-2) a step of partially inactivating at least one remaining functional group selected from the group consisting of alkoxy groups and hydroxyl groups in the conjugated diene-based graft polymer;
The method for producing a conjugated diene-based graft polymer according to claim 5, comprising: 7. The method for producing a conjugated diene-based graft polymer according to claim 5 or 6, wherein Z in the formula (II) is Si. The method for producing a conjugated diene-based graft polymer according to any one of claims 5 to 7, wherein the functional group V in formula (II) is an alkoxy group. The conjugated diene-based graft polymer according to any one of claims 1 to 4, which is obtained by the production method according to any one of claims 5 to 8. A polymer composition containing the conjugated diene-based graft polymer according to any one of claims 1 to 4 and 9. A molded article obtained by molding the polymer composition according to claim 10 .