Polymer composition comprising a modified polymer having a boron-containing functional group and method for making the same

Abstract

Provided is a method for producing a polymer having a boron-containing functional group that is suitable for the modification of various materials such as the modification of polar materials and the dispersion of inorganic materials in high yield; and a polymer composition containing a modified polymer having a boron-containing functional group that has both high reactivity and excellent storage stability for various polar functional groups. The method for producing a polymer composition containing a modified polymer having a boron-containing functional group comprises: a step (1) of anionically polymerizing at least one monomer selected from a conjugated diene and an aromatic vinyl compound in the presence of an anionic polymerizable active metal or active metal compound to produce an active terminal polymer (Z); and a step (2) of reacting the active terminal polymer (Z) obtained in the step (1) with a boronic acid compound, wherein the boronic acid compound has at least two partial structures represented by the following formula (I), and the Taft stereo parameter Es value of at least one R bonded to the oxygen atom contained in the partial structure is less than -0.30. B-O-R(I). (In formula (I), B represents a boron atom, O represents an oxygen atom, and R represents an organic group.)

Description

Technical Field

[0001] The present invention relates to polymer compositions and methods of making comprising modified polymers having boron-containing functional groups. Background Art

[0002] A method for synthesizing polymers having various functional groups, such as boron-containing functional groups, at the ends by anionic polymerization has been studied. For example, a method for introducing a boronic acid group into the end of a polymer has been studied, wherein the boronic acid group is an example of a boron-containing functional group, and it has been clarified that polymers having a boronic acid group or a disubstituted boronic acid group as a boron-containing functional group at the end are useful as resin modifiers such as compatibilizers for thermoplastic resins having hydroxyl groups in the side chains such as ethylene-vinyl alcohol copolymers (see Patent Document 1). In addition, for the purpose of improving the dispersibility of silica, a disubstituted boronic acid group-modified polymer containing at least one polymer of a styrene monomer and a diene monomer has been studied in tire applications (see Patent Document 2).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 7-25918

[0006] Patent Document 2: International Publication No. 2014 / 088092 Summary of the invention

[0007] Problems to be solved by the invention

[0008] Patent Document 1 specifically studies the conjugated diene polymer having a terminal having boric acid by reacting the terminal of an anionic polymerized active terminal polymer with trimethyl borate. However, according to the research of the present inventors, it is clear that although the method of Patent Document 1 can be used to obtain a conjugated diene polymer having a terminal having boric acid, the reactivity of the boric acid ester is insufficient in the production method, and a large amount of unmodified polymer without a boric acid group may be included. Therefore, even if the polymer obtained in Patent Document 1 is used for resin modification, etc., due to the small proportion of polymers having a boric acid group, the following problems sometimes arise: there are a variety of polymers that cannot react with polymers containing groups reactive with boric acid groups, the grafting efficiency is insufficient, and the bleed-out component increases.

[0009] Patent Document 2 records that a conjugated diene polymer having a disubstituted boronic acid group at the polymer end has the effect of improving the dispersibility of silica. In the method described in Patent Document 2, a polymerizable composition containing only a disubstituted boronic acid group-modified polymer is obtained in high yield. The Lewis acidity of the disubstituted boronic acid is high, and the reactivity with Lewis basic compounds is excellent, but it is easy to produce protons in the presence of moisture, therefore, a reduction in storage stability is caused in the conjugated diene polymer. In addition, in the method described in Patent Document 2, due to the oligomer containing low molecular weight boric acid at the end, sometimes problems such as competing reaction with the polymer and reducing the grafting efficiency are generated.

[0010] The present invention is made in view of the above-mentioned actual situation, and its purpose is to provide a method for producing a polymer having a boron-containing functional group suitable for modification of various materials such as modification of polar materials and dispersion of inorganic materials in high yield; and a polymer composition containing a modified polymer having a boron-containing functional group that has both high reactivity and excellent storage stability (for example, heat resistance) with respect to various polar functional groups.

[0011] Methods used to solve problems

[0012] As a result of intensive research, the present inventors found that a desired polymer can be obtained at a high yield by using a predetermined anionic polymerization active terminal polymer and a boronic acid compound satisfying predetermined parameters in the process of manufacturing a polymer having a boron-containing functional group. Furthermore, the inventors found that a specific polymer composition containing a modified polymer containing a predetermined borate ester group and a modified polymer containing a predetermined disubstituted boronic acid group has excellent reactivity with polar functional groups and storage stability, thereby completing the present invention.

[0013] That is, the present invention provides the following [1] to [3].

[0014] [1] A method for producing a polymer composition containing a modified polymer having a boron-containing functional group, comprising: step (1) of anionically polymerizing at least one monomer selected from a conjugated diene and an aromatic vinyl compound in the presence of an active metal or an active metal compound capable of anionic polymerization to produce an active terminal polymer (Z); and step (2) of reacting the active terminal polymer (Z) obtained in step (1) with a boronic acid compound, wherein the boronic acid compound has at least two partial structures represented by the following formula (I), and the Taft stereo parameter Es value of at least one R bonded to an oxygen atom contained in the partial structure is less than -0.30.

[0015] BOR(I)

[0016] (In formula (I), B represents a boron atom, O represents an oxygen atom, and R represents an organic group.)

[0017] [2] The method for producing a polymer composition according to [1], wherein in step (2), the boronic acid compound is mixed with a polar compound and then added to the active terminal polymer (Z) to react.

[0018] [3] A polymer composition comprising:

[0019] 55 to 99% by mass of at least one boric acid-based modified polymer (A) selected from a modified polymer containing a boronic acid group represented by the following formula (II), a modified polymer containing a borate ester group represented by the following formula (III), and a modified polymer containing a borate salt represented by the following formula (IV); and

[0020] 1 to 45% by mass of at least one disubstituted boronic acid-based modified polymer (B) selected from a modified polymer containing a disubstituted boronic acid group represented by the following formula (V) or (VI), a modified polymer containing a disubstituted boronic acid ester group represented by the following formula (VII) or (VIII), and a modified polymer containing a disubstituted boric acid salt represented by the following formula (IX) or (X).

[0021] [Chemistry 1]

[0022]

[0023] (In the above formula, P 1 , P 2 and P 3 It represents a polymer chain comprising at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit;

[0024] R 1 and R 2 Each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and R 1 and R 2 At least one of them is an alkyl group having 1 to 12 carbon atoms, or R 1 With R 2 bonded to form an alkylene chain having 2 to 24 carbon atoms;

[0025] R 3 , R 4 and R 5 Each independently represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or a polymer chain containing at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit, and R 3 , R 4 and R 5 At least one of them is an alkyl group having 1 to 12 carbon atoms, or a polymer chain containing at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit, or R3 With R 4 , R 3 With R 5 , or R 4 With R 5 optionally bonded to form an alkylene chain having 2 to 24 carbon atoms, R 3 , R 4 and R 5 Optional bonds are formed to form a trivalent saturated hydrocarbon chain having 3 to 36 carbon atoms; M represents an alkali metal or 1 / 2 alkaline earth metal.

[0026] [Chemistry 2]

[0027]

[0028] (In the above formula, P 4 , P 5 , P 6 , P 7 , P 8 , P 9 , P 10 , P 11 and P 12 It represents a polymer chain comprising at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit;

[0029] R 6 , R 7 , R 8 , R 9 Each independently represents an alkyl group having 1 to 12 carbon atoms;

[0030] R 10 and R 11 are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, R 10 and R 11 At least one of them is an alkyl group having 1 to 12 carbon atoms, or R 10 With R 11 bonded to form an alkylene chain having 2 to 24 carbon atoms;

[0031] R 12 represents an alkyl group having 1 to 12 carbon atoms;

[0032] R 13 and R 14 are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, R 13 and R 14 At least one of them is an alkyl group having 1 to 12 carbon atoms, or R 13 With R 14 bonded to form an alkylene chain having 2 to 24 carbon atoms;

[0033] M represents 1 alkali metal or 1 / 2 alkaline earth metal. )

[0034] Effects of the Invention

[0035] According to the present invention, there are provided a polymer composition comprising a modified polymer containing a borate ester group and a modified polymer containing a disubstituted boronic acid group, which has both high reactivity with a polar functional group and excellent storage stability (for example, heat resistance), and a method for producing the polymer composition. DETAILED DESCRIPTION

[0036] Hereinafter, the present invention will be described in detail.

[0037] The polymer composition of the present invention comprises:

[0038] 55 to 99% by mass of at least one boric acid-based modified polymer (A) selected from a modified polymer containing a boronic acid group represented by the following formula (II), a modified polymer containing a borate ester group represented by the following formula (III), and a modified polymer containing a borate salt represented by the following formula (IV); and

[0039] 1 to 45% by mass of at least one disubstituted boronic acid-based modified polymer (B) selected from a modified polymer containing a disubstituted boronic acid group represented by the following formula (V) or (VI), a modified polymer containing a disubstituted boronic acid ester group represented by the following formula (VII) or (VIII), and a modified polymer containing a disubstituted boric acid salt represented by the following formula (IX) or (X).

[0040] In the present invention, the modified polymer containing a boronic acid group is represented by the following formula (II).

[0041] [Chemistry 3]

[0042]

[0043] In formula (II), P 1 It means a polymer chain containing at least one monomer unit selected from the group consisting of a conjugated diene unit and an aromatic vinyl compound unit.

[0044] In the present invention, the modified polymer containing a borate group is represented by the following formula (III).

[0045] [Chemistry 4]

[0046]

[0047] In formula (III), P 2 represents a polymer chain comprising at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit; R 1 and R 2Each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and R 1 and R 2 At least one of them is an alkyl group having 1 to 12 carbon atoms, or R 1 With R 2 The alkylene groups are bonded to form an alkylene chain having 2 to 24 carbon atoms.

[0048] The above R 1 and R 2 The Taft stereo parameter Es value of at least one of them is preferably -0.30 or less, more preferably -3.00 to -0.30, and even more preferably -1.55 to -0.39. 1 and R 2 It is a preferred method that all satisfy the above Es value. 1 and R 2 At least one of them is preferably n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, or cyclohexyl, more preferably isopropyl or n-butyl, and still more preferably isopropyl. 1 and R 2 Preferably, they are all n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl or cyclohexyl, more preferably, they are all isopropyl or n-butyl, and further preferably, they are all isopropyl. It should be noted that the Taft stereo parameter Es value is described below in the section of step (2) of the suitable production method of the polymer composition.

[0049] In the present invention, the modified polymer containing a borate is represented by the following formula (IV).

[0050] [Chemistry 5]

[0051]

[0052] In formula (IV), P 3 represents a polymer chain comprising at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit, R 3 , R 4 and R 5 Each independently represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or a polymer chain containing at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit, and R 3 , R 4 and R 5 At least one of them is an alkyl group having 1 to 12 carbon atoms, or a polymer chain containing at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit, or R 3 With R 4 , R 3 With R 5, or R 4 With R 5 optionally bonded to form an alkylene chain having 2 to 24 carbon atoms, R 3 , R 4 and R 5 They may be bonded to form a trivalent saturated hydrocarbon chain having 3 to 36 carbon atoms.

[0053] The above R 3 , R 4 and R 5 The Taft stereo parameter Es value of at least one of them is preferably -0.30 or less, more preferably -3.00 to -0.30, and even more preferably -1.55 to -0.39. 3 , R 4 and R 5 It is a preferred method that all satisfy the above Es value. 3 , R 4 and R 5 At least one of them is preferably n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, or cyclohexyl, more preferably isopropyl or n-butyl, and still more preferably isopropyl. 3 , R 4 and R 5 Preferably, they are all n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl or cyclohexyl, more preferably, they are all isopropyl or n-butyl, and further preferably, they are all isopropyl. M is 1 alkali metal or 1 / 2 alkaline earth metal, preferably lithium, sodium, potassium, more preferably lithium. It should be noted that 1 alkali metal means: in formula (IX), relative to 1 monovalent anionic group shown in brackets, the cation of the alkali metal is 1 valence, therefore, corresponding to the valence of the anionic group, the alkali metal is 1. Similarly, 1 / 2 alkaline earth metal means: in formula (IX), relative to 1 monovalent anionic group shown in brackets, the valence of the cation of the alkaline earth metal is 2 valences, therefore, corresponding to the valence of the anionic group, the alkaline earth metal is 1 / 2.

[0054] In the present invention, the modified polymer containing a disubstituted boronic acid group is represented by the following formula (V) or formula (VI).

[0055] [Chemistry 6]

[0056]

[0057] In formula (V), P 4 and P 5 It means a polymer chain containing at least one monomer unit selected from the group consisting of a conjugated diene unit and an aromatic vinyl compound unit.

[0058] [Chemistry 7]

[0059]

[0060] In formula (VI), P 6 represents a polymer chain comprising at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit, R 6 represents an alkyl group having 1 to 12 carbon atoms. 6 Preferred are methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl and cyclohexyl, more preferred are isopropyl and n-butyl, and further preferred is isopropyl.

[0061] In the present invention, the modified polymer containing a disubstituted borate group is represented by the following formula (VII) or formula (VIII).

[0062] [Chemistry 8]

[0063]

[0064] In formula (VII), P 7 and P 8 represents a polymer chain comprising at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit; R 7 represents an alkyl group having 1 to 12 carbon atoms. 7 The Taft stereo parameter Es value is preferably -0.30 or less, more preferably -3.00 to -0.30, and further preferably -1.55 to -0.39. 7 Preferred are n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl and cyclohexyl, more preferred are isopropyl and n-butyl, and further preferred is isopropyl.

[0065] [Chemistry 9]

[0066]

[0067] In formula (VIII), P 9 represents a polymer chain comprising at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit; R 8 is an alkyl group having 1 to 12 carbon atoms; R 9 is an alkyl group having 1 to 12 carbon atoms. 9 The Taft stereo parameter Es value is preferably -0.30 or less, more preferably -3.00 to -0.30, and further preferably -1.55 to -0.39. 9 Preferred are n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl and cyclohexyl, more preferred are isopropyl and n-butyl, and further preferred is isopropyl.

[0068] The above R 8Preferred are methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl and cyclohexyl, more preferred are isopropyl and n-butyl, and further preferred is isopropyl.

[0069] In the present invention, the modified polymer containing a disubstituted borate is represented by the following formula (IX) or formula (X).

[0070] [Chemistry 10]

[0071]

[0072] In formula (IX), P 10 and P 11 represents a polymer chain comprising at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit; R 10 and R 11 are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, R 10 and R 11 At least one of them is an alkyl group having 1 to 12 carbon atoms, or R 10 With R 11 bonded to form an alkylene chain having 2 to 24 carbon atoms; M represents an alkali metal or 1 / 2 alkaline earth metal.

[0073] The above R 10 and R 11 The Taft stereo parameter Es value of at least one of them is preferably -0.30 or less, more preferably -3.00 to -0.30, and even more preferably -1.55 to -0.39. 10 and R 11 It is a preferred method that all satisfy the above Es value. 10 and R 11 At least one of them is preferably n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, or cyclohexyl, more preferably isopropyl or n-butyl, and still more preferably isopropyl. 10 and R 11 Preferably, they are all n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl or cyclohexyl, more preferably, they are all isopropyl or n-butyl, and further preferably, they are all isopropyl. M is an alkali metal or 1 / 2 alkaline earth metal, preferably lithium, sodium, potassium, and more preferably lithium.

[0074] [Chemistry 11]

[0075]

[0076] In formula (X), P 12 represents a polymer chain comprising at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit; R 12represents an alkyl group having 1 to 12 carbon atoms;

[0077] R 13 and R 14 are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, R 13 and R 14 At least one of them is an alkyl group having 1 to 12 carbon atoms, or R 13 With R 14 bonded to form an alkylene chain having 2 to 24 carbon atoms;

[0078] M represents one alkali metal or one-half alkaline earth metal.

[0079] The above R 13 and R 14 The Taft stereo parameter Es value of at least one of them is preferably -0.30 or less, more preferably -3.00 to -0.30, and even more preferably -1.55 to -0.39. 13 and R 14 It is a preferred method that all satisfy the above Es value. 13 and R 14 At least one of them is preferably n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, or cyclohexyl, more preferably isopropyl or n-butyl, and still more preferably isopropyl. 13 and R 14 Preferably, they are all n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl or cyclohexyl, more preferably, they are all isopropyl or n-butyl, and further preferably, they are all isopropyl.

[0080] The above R 12 Preferred are methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl and cyclohexyl, more preferred are isopropyl and n-butyl, and further preferred is isopropyl.

[0081] The above-mentioned M is preferably lithium, sodium or potassium, and more preferably lithium.

[0082] As mentioned above, the above formulas (II) to (X) contain P 1 ~P 12 The polymer chain shown comprises at least one monomer unit selected from the group consisting of a conjugated diene unit and an aromatic vinyl compound unit.

[0083] As the formation of 1 ~P 12The conjugated diene of the conjugated diene unit that can be included in the present invention includes, for example, 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 chloroprene. Among these conjugated dienes, butadiene and isoprene are preferred, and butadiene is more preferred. The conjugated dienes that form the above-mentioned conjugated diene units can be used alone or in combination of two or more.

[0084] As the formation of 1 ~P 12 The aromatic vinyl compound of the aromatic vinyl compound unit that can be included in the above-mentioned aromatic vinyl compound unit can include, for example, styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-propylstyrene, 4-tert-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 and divinylbenzene. Among these aromatic vinyl compounds, styrene, α-methylstyrene and 4-methylstyrene are preferred. The aromatic vinyl compound forming the above-mentioned aromatic vinyl compound unit can be used alone or in combination of two or more.

[0085] P 1 ~P 12 It is a preferred embodiment that 30% by mass or more of all monomer units in the polymer chain are at least one monomer unit selected from butadiene and isoprene. The total content of butadiene units and isoprene units is relative to the total content of P 1 The total monomer units in the polymer chain are preferably 50 to 100% by mass, more preferably 60 to 100% by mass.

[0086] P 1 ~P 12 The content of monomer units other than butadiene units and isoprene units in all monomer units of the polymer chain is preferably 50% by mass or less, more preferably 40% by mass or less.

[0087] As a P 1 ~P 12The polymer chain may include a homopolymer chain or a copolymer chain (random copolymer chain, block copolymer chain) of at least one monomer selected from the monomers selected from the above-mentioned conjugated dienes and aromatic vinyl compounds; or a copolymer chain (random copolymer chain, block copolymer chain) containing monomer units of monomers other than the above-mentioned monomers.

[0088] Become a P 1 ~P 12 The weight average molecular weight (Mw) of the polymer chain is 1,000 or more and 1,000,000 or less, more preferably 2,000 or more and 500,000 or less, and further preferably 3,000 or more and 100,000 or less. In addition, the weight average molecular weight (Mw) of the polymer composition of the present invention is also preferably within the above range. If the Mw of the above polymer chain is within the above range, there is a tendency for excellent process passability and good economy during manufacturing. It should be noted that in the present invention, unless otherwise specified, Mw is the weight average molecular weight calculated by standard polystyrene obtained by gel permeation chromatography (GPC).

[0089] Become a P 1 ~P 12 The molecular weight distribution (Mw / Mn) of the polymer chain is preferably 1.0 to 20.0, more preferably 1.0 to 10.0, further preferably 1.0 to 5.0, further preferably 1.0 to 2.0, particularly preferably 1.0 to 1.5, and more particularly preferably 1.0 to 1.2. If Mw / Mn is within the aforementioned range, the viscosity deviation of the resulting modified polymer is small, which is more preferred. In addition, from the viewpoint of reducing the viscosity deviation, the molecular weight distribution (Mw / Mn) of the polymer composition of the present invention is also preferably within the above range. It should be noted that in the present invention, Mn refers to the number average molecular weight, and Mn is the number average molecular weight converted to standard polystyrene obtained by GPC measurement. In addition, the molecular weight distribution (Mw / Mn) refers to the ratio (Mw / Mn) of the weight average molecular weight (Mw) converted to standard polystyrene obtained by GPC measurement and the number average molecular weight (Mn).

[0090] Become a P 1 ~P 12The vinyl content of the polymer chain is not particularly limited, and 90 mol% or less is a preferred embodiment, more preferably 0.01 to 90 mol%, further preferably 0.1 to 80 mol%, and further preferably 1 to 70 mol%. In addition, the vinyl content of the polymer composition of the present invention is also preferably within the above range. In the present invention, "vinyl content" refers to the total mole % of conjugated diene units bonded in the form of 1,2-bonds, 3,4-bonds (except for farnesene) and 3,13-bonds (in the case of farnesene) in the total 100 mol % of conjugated diene units contained in the polymer chain or polymer (conjugated diene units bonded in the form of 1,4-bonds (except for farnesene) and 1,13-bonds (in the case of farnesene)). The vinyl content is expressed as 1 H-NMR is calculated based on the area ratio of the peak derived from the conjugated diene unit bonded in the form of 1,2-bond, 3,4-bond (in the case of farnesene) and 3,13-bond (in the case of farnesene) to the peak derived from the conjugated diene unit bonded in the form of 1,4-bond (in the case of farnesene) and 1,13-bond (in the case of farnesene).

[0091] Become a P 1 ~P 12 The vinyl content of the polymer chain can be designed according to the purpose. For example, if the vinyl content is less than 70 mol%, the glass transition temperature (Tg) of the polymer tends to be lower, and the fluidity and low-temperature properties of the obtained polymer composition tend to be excellent.

[0092] When the polymer composition of the present invention is produced by the method described below, the vinyl content can be adjusted to a desired value by controlling the type of solvent used in step (1), the polar compound used as needed, the polymerization temperature, and the like.

[0093] Become a P 1 ~P 12 The glass transition temperature (Tg) of the polymer chain may vary according to the vinyl content of the butadiene unit, the isoprene unit and the conjugated diene unit other than the butadiene unit and the isoprene unit, the type of the conjugated diene unit, the content of the unit derived from the monomer other than the conjugated diene, etc., and is preferably -150 to 50°C, more preferably -130 to 50°C, and further preferably -130 to 30°C. If Tg is within the above range, for example, it is possible to suppress the viscosity from becoming high and to facilitate handling. In addition, from the viewpoint of ease of handling, the glass transition temperature (Tg) of the polymer composition of the present invention is also preferably within the above range. It should be noted that in the present invention, Tg is the peak value of DDSC determined by differential scanning calorimetry (DSC).

[0094] The polymer composition of the present invention is characterized in that, relative to the mass of all polymers contained in the composition, it comprises:

[0095] 55 to 99% by mass of at least one boronic acid-based modified polymer (A) selected from the group consisting of a modified polymer containing a boronic acid group represented by the above formula (II), a modified polymer containing a borate ester group represented by the above formula (III), and a modified polymer containing a borate salt represented by the following formula (IV); and

[0096] 1 to 45% by mass of at least one disubstituted boronic acid-based modified polymer (B) selected from the group consisting of a modified polymer containing a disubstituted boronic acid group represented by the above formula (V) or (VI), a modified polymer containing a disubstituted boronic acid ester group represented by the above formula (VII) or (VIII), and a modified polymer containing a disubstituted boric acid salt represented by the above formula (IX) or (X).

[0097] By including boric acid modified polymer (A) and disubstituted boric acid modified polymer (B) in the polymer composition of the present invention with the above ratio, it is possible to take into account the high reactivity and excellent storage stability of polar functional groups. It should be noted that, typically, the polymer composition of the present invention refers to a mixture of a polymer modified by a boron-containing functional group and an unmodified polymer that is not modified even by the functional group modification. Therefore, the polymer composition of the present invention is only composed of a mixture of a polymer modified by a boron-containing functional group and an unmodified polymer that is not modified even by the functional group modification, which is a preferred mode.

[0098] The content of the boric acid modified polymer (A) and the disubstituted boric acid modified polymer (B) in the polymer composition is determined according to the boron concentration and 11 The boron concentration can be determined by ICP emission analysis. 11 The contents of (A) and (B) are calculated from the area ratio of the signals in the B-NMR spectrum. In addition, when a borate compound is used to obtain a polymer composition, since the molecular weight of (B) is larger than that of (A), the contents of (A) and (B) are also calculated from the area ratio of the GPC spectrum. In the case where the peak separation is low, the peaks are separated in the form of Gaussian distribution peaks to calculate the area ratio.

[0099] From the viewpoint of further improving the stability of the polymer composition, the content ratio of the boronic acid modified polymer (A) and the disubstituted boronic acid modified polymer (B) in the polymer composition of the present invention is preferably 65 to 99% by mass of the boronic acid modified polymer (A) and 1 to 35% by mass of the disubstituted boronic acid modified polymer (B), more preferably 68 to 99% by mass of the boronic acid modified polymer (A) and 1 to 32% by mass of the disubstituted boronic acid modified polymer (B), further preferably 79 to 99% by mass of the boronic acid modified polymer (A) and 1 to 31% by mass of the disubstituted boronic acid modified polymer (B), particularly preferably 80 to 99% by mass of the boronic acid modified polymer (A) and 1 to 20% by mass of the disubstituted boronic acid modified polymer (B).

[0100] The content ratio of the boronic acid modified polymer (A) and the disubstituted boronic acid modified polymer (B) in the polymer composition of the present invention can be controlled by, for example, the Taft stereo parameter Es value, the reaction temperature, the amount of the polar compound, etc. in the production method of the modified polymer described below.

[0101] The Mw of the boric acid-modified polymer (A) is preferably 2,000 or more and 200,000 or less, and more preferably 4,000 or more and 100,000 or less.

[0102] The Mw of the disubstituted boronic acid-based modified polymer (B) is preferably 4,000 or more and 400,000 or less, and more preferably 8,000 or more and 200,000 or less.

[0103] In addition, the polymer composition of the present invention may further contain at least one of a boron crosslinked terpolymer (C) represented by the following formula (XI) and an unmodified polymer (D) having no boron-containing functional group, within a range that does not impair the reactivity of the polymer composition, and the contents of (C) and (D) in the polymer composition are each preferably 20% by mass or less.

[0104] [Chemistry 12]

[0105]

[0106] In the above formula (XI), P 13 , P 14 and P 15 It means a polymer chain containing at least one monomer unit selected from the group consisting of a conjugated diene unit and an aromatic vinyl compound unit.

[0107] The content of the modified polymer having a boron-containing functional group (typically, a modified polymer having a boron-containing functional group at a terminal) in the polymer composition is preferably 60% by mass or more, more preferably 65% ​​by mass or more, based on the mass of all polymers contained in the composition.

[0108] The boron content in the polymer composition can be determined by quantifying the boron content per unit weight of the polymer composition by ICP emission analysis.

[0109] From the viewpoint of achieving a balance between stability and reactivity of the polymer composition, the boron content in the polymer composition is more preferably 0.001 to 5% by mass, and even more preferably 0.003 to 2% by mass.

[0110] The method for producing a polymer composition containing a modified polymer having a boron-containing functional group of the present invention is preferably a method comprising the following steps (1) and (2).

[0111] Step (1): a step of producing an active terminal polymer (hereinafter also referred to as active terminal polymer (Z)) by anionically polymerizing at least one monomer selected from a conjugated diene and an aromatic vinyl compound in the presence of an anionically polymerizable active metal or active metal compound.

[0112] Specific examples and suitable embodiments of the monomers forming the structural units derived from the monomers constituting the active terminal polymer (Z), and specific examples and suitable embodiments of the structural units derived from the monomers contained in the active terminal polymer (Z) are described in conjunction with the use of P in the above-mentioned polymer composition. 1 ~P 13 The same applies to the polymer chain containing at least one monomer unit selected from the group consisting of a conjugated diene unit and an aromatic vinyl compound unit.

[0113] The active terminal polymer (Z) having an anionic polymerization active terminal can be produced using a known polymerization method. For example, the active terminal polymer (Z) can be obtained by anionically polymerizing the monomer in a solvent that is inactive to the polymerization terminal using an active metal or active metal compound that can undergo anionic polymerization as an initiator in the presence of a polar compound as required.

[0114] As the active metal or active metal compound capable of anionic polymerization, an organic alkali metal compound is preferred, and an organic lithium compound is more preferred.

[0115] Examples of the active metal include alkali metals such as lithium, sodium, and potassium; alkaline earth metals such as beryllium, magnesium, calcium, strontium, and barium; and lanthanide rare earth metals such as lanthanum and neodymium. Among these, alkali metals and alkaline earth metals are preferred, and alkali metals are more preferred.

[0116] As the above-mentioned active metal compound, an organic alkali metal compound is preferred. As the organic alkali metal compound, for example, organic monolithium compounds such as methyl lithium, ethyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, amyl lithium, hexyl lithium, phenyl lithium, and stilbene lithium can be listed; multifunctional organic lithium compounds such as dilithium methane, dilithium naphthalene, 1,4-dilithium butane, 1,4-dilithium-2-ethylcyclohexane, 1,3,5-trilithium benzene; sodium naphthalene, potassium naphthalene, etc. Among these organic alkali metal compounds, organic lithium compounds are preferred. As the above-mentioned organic lithium compounds, for example, methyl lithium, ethyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, amyl lithium, etc. can be listed.

[0117] 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 aromatic hydrocarbons such as benzene, toluene, and xylene.

[0118] Polar compounds may be added during the above anionic polymerization. Polar compounds usually do not deactivate the reaction in anionic polymerization and are used to adjust the microstructure (vinyl content) of the conjugated diene site. 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, phosphine compounds, and the like. Polar compounds are usually used in an amount of 0.01 to 1000 moles relative to 1 mole of the organic alkali metal compound.

[0119] The temperature of the anionic polymerization is usually in the range of -80 to 150° C., preferably in the range of 0 to 100° C., and more preferably in the range of 10 to 90° C. The polymerization method may be either a batch method or a continuous method.

[0120] Step (2): A step of reacting the active terminal polymer (Z) with a boronic acid compound having at least two partial structures represented by the following formula (I) (hereinafter, this structure is also referred to as partial structure (I)), and having a Taft stereo parameter Es value of at least one R bonded to an oxygen atom contained in the partial structure (I) of less than -0.30.

[0121] BOR(I)

[0122] (In formula (I), B represents a boron atom, O represents an oxygen atom, and R represents an organic group.)

[0123] Here, the Taft stereo parameter Es value refers to the relative speed based on the methyl substituent effect at the esterification reaction speed under the acidity of the substituted carboxylic acid, and is a general index indicating the stereo bulkiness of the substituent. In the present invention, the Es (Taft) value described in Table 1 described in Tetrahedron, 1978, Vol. 34, pages 3553-3562 and the value measured by the method described in the above literature are included. Regarding this value, the value of the methyl group is 0.0, for example, the value of the hydrogen atom is 1.24, the value of the ethyl group is -0.08, the value of the n-propyl group is -0.36, the value of the isopropyl group is -0.47, the value of the n-butyl group is -0.39, the value of the sec-butyl group is -1.13, the value of the isobutyl group is -0.93, the value of the tert-butyl group is -1.54, and the value of the cyclohexyl group is -0.79.

[0124] The Taft stereo parameter Es value is preferably -3.00 to -0.30, more preferably -1.55 to -0.39.

[0125] When the Taft stereo parameter Es value of at least one R included in the partial structure (I) is -0.30 or less, it is difficult for a bulky boronic acid compound to form a cluster structure containing the boronic acid compound due to steric hindrance, and thus a polymer composition having high electrophilicity, improved reaction rate with the active terminal, and high content ratio of the boronic acid-modified polymer (A) can be obtained. In addition, from the viewpoint of further improving the reaction rate, it is a preferred embodiment that all R bonded to the oxygen atom included in the partial structure (I) satisfy the above Es value.

[0126] R satisfying the above Es value is preferably n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, or cyclohexyl, more preferably isopropyl or n-butyl, and still more preferably isopropyl.

[0127] The above-mentioned boronic acid compound is a boronic acid compound reactive with the active terminal of the active terminal polymer (Z) obtained by anionic polymerization. Among these, boric acid esters represented by the following formula (XII) are preferred.

[0128] [Chemistry 13]

[0129]

[0130] In the above formula (XII), R 16 , R 17 and R 18 It represents a hydrocarbon group having 1 to 12 carbon atoms.

[0131] The above R 16 , R 17 and R 18The Taft stereo parameter Es value of at least one of them is preferably -0.30 or less, more preferably -3.00 to -0.30, and further preferably -1.55 to -0.39. 16 , R 17 and R 18 It is a preferred method that all satisfy the above Es value. 16 , R 17 and R 18 At least one of them is preferably n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, or cyclohexyl, more preferably isopropyl or n-butyl, and still more preferably isopropyl. 16 , R 17 and R 18 Preferably, each of them is n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl or cyclohexyl, more preferably isopropyl or n-butyl, and further preferably isopropyl.

[0132] Examples of the boric acid ester represented by the formula (XII) include tri-n-propyl borate, tri-n-butyl borate, tri-isopropyl borate, tri-sec-butyl borate, tri-isobutyl borate, tricyclohexyl borate, etc. Among these, tri-n-propyl borate, tri-n-butyl borate, and tri-isopropyl borate are preferred.

[0133] In step (2), the boronic acid compound is used in an amount of preferably 0.5 to 10 mol, more preferably 1 to 5 mol, based on 1 mol of the active terminal polymer (Z).

[0134] In the step (2), it is preferred that the polar compound is mixed with the boronic acid compound and then the mixture is reacted with the active terminal polymer (Z).

[0135] Examples of the polar compound include ether compounds such as dibutyl ether, tetrahydrofuran, and ethylene glycol diethyl ether; tertiary amines such as tetramethylethylenediamine and trimethylamine; alkali metal alkoxides, phosphine compounds, and the like. The polar compound is usually used in an amount of 0.01 to 1000 mol relative to the boric acid compound used in step (2). By adding the polar compound, the molecular association of the boric acid compound can be dissociated, thereby improving the reactivity.

[0136] The reaction temperature of the active terminal polymer (Z) and the boronic acid compound in the step (2) is usually in the range of -80 to 150°C, preferably in the range of 0 to 100°C, and more preferably in the range of 10 to 90°C.

[0137] After the reaction of the active terminal polymer (Z) with the boronic acid compound in the above step (2), a polymerization inhibitor for the active terminal polymer (Z) may be further added. By adding the polymerization inhibitor in this way, it is possible to reliably suppress the side reaction caused by the active terminal contained in the active terminal polymer (Z) remaining after the reaction with the boronic acid compound. Examples of the polymerization inhibitor include alcohols such as methanol, ethanol, n-propanol, and isopropanol.

[0138] The reaction method of step (2) may be either a batch method or a continuous method.

[0139] The polymer composition obtained by the production method of the present invention is recovered from the reaction product obtained by the above step (2). The method for recovering the polymer composition is not particularly limited, and when the reaction product is obtained in step (2) in the form of a solution containing the polymer composition, the polymer composition can be recovered by, for example, injecting the obtained solution into a poor solvent such as methanol to precipitate the polymer composition, or by washing the polymer solution with water, separating it, and then drying it to separate the above polymer composition.

[0140] The polymer composition obtained in the present invention (hereinafter also referred to as polymer composition (α)) may be further added with other components such as other polymers (β) other than the polymer composition (α) and used as a resin composition. The other polymer (β) may be a thermoplastic polymer (β1) or a curable polymer (β2).

[0141] Examples of the thermoplastic polymer (β1) include acrylic resins such as polymethyl methacrylate and (meth)acrylate polymers or copolymers; olefin resins such as polyethylene, ethylene-vinyl acetate copolymers, polypropylene, polybutene-1, poly-4-methylpentene-1, and polynorbornene; ethylene ionomers; styrene resins such as polystyrene, styrene-maleic anhydride copolymers, high-impact polystyrene, AS resins, ABS resins, AES resins, AAS resins, ACS resins, and MBS resins; styrene-methyl methacrylate copolymers; styrene-methyl methacrylate copolymers; - Maleic anhydride copolymer; polyester resins such as polyethylene terephthalate, polybutylene terephthalate, and polylactic acid; polyamides such as nylon 6, nylon 66, and polyamide elastomers; polycarbonate; polyvinyl chloride; polyvinylidene chloride; polyvinyl acetate; partially saponified polyvinyl alcohol; polyvinyl alcohol; ethylene-vinyl alcohol copolymer; polyacetal; polyvinylidene fluoride; polyurethane; modified polyphenylene ether; polyphenylene sulfide; silicone rubber modified resin; acrylic rubber; silicone rubber; styrene thermoplastic elastomers such as SEPS, SEBS, and SIS; olefin rubbers such as IR, EPR, and EPDM. The thermoplastic polymer (β1) may be used alone or in combination of two or more.

[0142] As curable polymer (β2), for example, epoxy resin, unsaturated polyester resin, epoxy (meth) acrylate resin, ester (meth) acrylate resin, phenolic resin, urea resin, melamine resin, thermosetting urethane resin, silicone resin, imide resin, furan resin, alkyd resin, allyl resin, diallyl phthalate resin can be listed. Among these, from the viewpoint of the basic physical properties of the obtainable and cured product, in addition, from the viewpoint of obtaining the removability of bubbles, the toughness of the obtained cured product, etc., epoxy resin, unsaturated polyester resin and epoxy (meth) acrylate resin are preferably used, wherein epoxy resin and unsaturated polyester resin are more preferably used, and epoxy resin is further preferably used. Curable polymer (β2) can be used alone or in combination of two or more.

[0143] When the resin composition contains the polymer composition (α) and the other polymer (β), the mass ratio (α) / (β) of the polymer composition (α) to the other polymer (β) is preferably 50 / 50 to 99 / 1.

[0144] In addition, various additives can be added to the resin composition to the extent that the effect of the present invention is not impaired. For example, when the other polymer (β) is a thermoplastic polymer (β1), as the additive, reinforcing agents or fillers such as calcium carbonate, silica, carbon black, glass fiber, clay, process oil, polyethylene glycol, glycerol, phthalate and other plasticizers can be used as additives. In addition, as other additives, for example, heat stabilizers, antioxidants, ultraviolet absorbers, colorants, pigments, lubricants, surfactants, etc. can be listed. Furthermore, as the additive, a foaming agent can be listed, and a foam can be made from a polymer composition comprising a foaming agent and a thermoplastic polymer (β1).

[0145] For example, when the other polymer (β) is a curable polymer (β2), the additives include curing agents, curing accelerators, known rubbers, thermoplastic elastomers, impact modifiers such as core-shell particles, fillers (inorganic particles such as silica, talc, calcium carbonate, aluminum hydroxide, etc.), flame retardants, defoaming agents, pigments, dyes, antioxidants, weathering agents, lubricants, release agents, etc.

[0146] The method of mixing the other polymer (β) with the polymer composition (α) of the present invention can be prepared by a common mixing method of polymer substances according to the composition ratio of each component and the like.

[0147] When the other polymer (β) is a thermoplastic polymer (β1), the resin composition can be prepared using a mixing device such as an extruder, an open roll, a Banbury mixer, a kneader, etc. In the present invention, melt kneading using such a mixing device is a preferred embodiment.

[0148] When the other polymer (β) is a curable polymer (β2), the resin composition can be prepared by, for example, sufficiently mixing with a stirrer, followed by melt kneading with an open roll, an extruder, etc., followed by cooling and pulverization.

[0149] Example

[0150] The present invention will be described in more detail below by way of examples, but the present invention is not limited to these examples. In the following examples and comparative examples, the physical properties of the polymer compositions were evaluated by the following methods.

[0151] (1) Weight average molecular weight (Mw), number average molecular weight (Mn), molecular weight distribution (Mw / Mn)

[0152] The weight average molecular weight (Mw), number average molecular weight (Mn), and molecular weight distribution (Mw / Mn) of the conjugated diene graft copolymer and polymers in each production stage were determined in terms of standard polystyrene by gel permeation chromatography (GPC).

[0153] Equipment: GPC equipment "HLC-8220" manufactured by Tosoh Corporation

[0154] Separation column: "TSKgel SuperMultiporeHZ-M (column diameter = 4.6 mm, column length = 15 cm)" manufactured by Tosoh Corporation (two columns were connected in series and used)

[0155] Eluent: Tetrahydrofuran

[0156] Eluent flow rate: 0.35mL / min

[0157] Column temperature: 40°C

[0158] Detection method: Differential refractive index (RI)

[0159] Injection volume: 10μl

[0160] Concentration: 1mg / 1cc (conjugated diene graft copolymer / THF)

[0161] (2) Vinyl content and styrene-derived structural unit content

[0162] use 1The vinyl content of the modified polymer and the polymers in each stage of its production, and the content of the structural unit derived from styrene are calculated by H-NMR. The vinyl content is calculated from the area ratio of the signal of the double bond derived from the structural unit derived from vinylated conjugated diene to the signal of the double bond derived from the structural unit derived from unvinylated conjugated diene in the obtained spectrum, and the content of the structural unit derived from styrene is calculated from the area ratio of the signal of the aromatic ring derived from the structural unit derived from styrene to the signal of the double bond derived from the structural unit derived from conjugated diene.

[0163] Equipment: Nuclear magnetic resonance equipment "JNM-ECX400" manufactured by NEC Corporation

[0164] Solvent: deuterated chloroform

[0165] Measuring temperature: 50℃

[0166] Cumulative times: 1024 times

[0167] (3) Mass ratio of boronic acid modified polymer (A) and disubstituted boronic acid modified polymer (B) (mass %)

[0168] Since the molecular weight of the disubstituted boronic acid modified polymer (B) is larger than that of the boronic acid modified polymer (A), the mass ratio (mass %) of the polymers (A) and (B) is calculated based on the area ratio obtained by gel permeation chromatography (GPC). When the peak resolution is low, the peaks are separated in the form of Gaussian distribution peaks, and the mass ratio (mass %) is calculated based on the area ratio.

[0169] (4) Boron-containing functional group introduction rate (mass %)

[0170] The introduction rate of boron-containing functional groups is calculated as follows: after decomposing the polymer composition after removing the unreacted boric acid compound by water washing using a microwave decomposition device, it is calculated based on the boron atom content based on ICP emission analysis and the component ratio of the polymer component measured by gel permeation chromatography (GPC). The introduction rate of boron-containing functional groups is calculated based on the sum of the boric acid-modified polymer (A) and the disubstituted boric acid-modified polymer (B) after deducting the mass of the unmodified substance from the mass of the entire polymer composition.

[0171] <Microwave Decomposition>

[0172] Installation: MILESTONE, ETHOS UP

[0173] Solvent: Nitric acid

[0174] Decomposition temperature: 210℃

[0175] Decomposition time: 30 minutes

[0176] <ICP emission analysis>

[0177] Apparatus: Thermo Fisher Scientific, iCAP7400 Duo

[0178] (5) Contents of boric acid-modified polymer (A) and disubstituted boric acid-modified polymer (B) in the polymer composition

[0179] Calculation is performed based on the mass ratio of the aforementioned boric acid-modified polymer (A) and disubstituted boric acid-modified polymer (B), and the value of the boron-containing functional group introduction rate.

[0180] (6) Reactivity

[0181] The reactivity of the modified polymer is evaluated as follows: Using 1 1H-NMR, based on the signal change when adding catechol in the same molar amount as the polymer initiation end to the deuterated solvent solution of the polymer, evaluation is carried out according to the following criteria. The amount of polymer initiation end is determined using 1 1H-NMR, and calculated based on the integral ratio of the alkyl group derived from alkyllithium and the integral ratio of the signal of the double bond derived from the structural unit of conjugated diene.

[0182] A: The amount of catechol with signal displacement is 70 mol% or more

[0183] B: The amount of catechol with signal displacement is 50 mol% or more and less than 70 mol%

[0184] C: The amount of catechol with signal displacement is 25 mol% or more and less than 50 mol%

[0185] D: The amount of catechol with signal displacement is less than 25 mol%

[0186] (7) Heat resistance

[0187] The heat resistance of the modified polymer is evaluated by the appearance change during heating based on visual observation. The modified polymer is coated on a glass slide, and the heat resistance is evaluated according to the appearance after heating at 100 °C for 12 h in the atmosphere according to the following criteria.

[0188] A: No appearance change

[0189] B: Gelation or yellowing

[0190] [Example 1]

[0191] (Step (1))

[0192] A 5L autoclave that had been dried thoroughly was purged with nitrogen, and 1200 g of cyclohexane and 54.0 g of sec-butyl lithium (10.5% by mass cyclohexane solution) were added. After the temperature was raised to 50° C., 1300 g of butadiene was added successively at 10 ml / min while the polymerization temperature was controlled to 50° C. under stirring conditions. After the addition of butadiene, the mixture was heated for 1 hour to terminate the polymerization.

[0193] (Process (2))

[0194] 16.6 g of triisopropyl borate was added to the polymer solution obtained by step (1) to introduce boric acid into the polymerization end. Ion exchange water was added to the obtained polymer solution and stirred to wash the polymer solution. After confirming that the polymer solution phase and the aqueous phase have been separated, the polymer solution phase was recovered and dried under reduced pressure at 90° C. for 12 hours to obtain a polymer composition (1) comprising a boronic acid-modified polymer (A1) and a disubstituted boronic acid-modified polymer (B1). The physical properties of the obtained polymer composition (1) are described in Table 2.

[0195] [Example 2]

[0196] (Process (1))

[0197] A 5L autoclave that had been dried thoroughly was purged with nitrogen, and 1200 g of cyclohexane, 54.0 g of sec-butyl lithium (10.5% by mass cyclohexane solution), and 2.06 g of tetramethylethylenediamine (TMEDA) were added. After the temperature was raised to 50° C., 1300 g of butadiene was added successively at 10 ml / min while the polymerization temperature was controlled to 50° C. under stirring conditions. After the addition of butadiene, the mixture was heated for 1 hour to terminate the polymerization.

[0198] (Process (2))

[0199] 16.6 g of triisopropyl borate was added to the polymer solution obtained by step (1) to introduce boric acid into the polymerization end. Ion exchange water was added to the obtained polymer solution and stirred to wash the polymer solution. After confirming that the polymer solution phase and the aqueous phase have been separated, the polymer solution phase was recovered and dried under reduced pressure at 90° C. for 12 hours to obtain a polymer composition (2) comprising a boronic acid modified polymer (A2) and a disubstituted boronic acid modified polymer (B2). The physical properties of the obtained polymer composition (2) are described in Table 2.

[0200] [Example 3]

[0201] (Process (1))

[0202] A 5L autoclave that had been dried thoroughly was purged with nitrogen, and 1200 g of cyclohexane and 54.0 g of sec-butyl lithium (10.5% by mass cyclohexane solution) were added. After the temperature was raised to 50° C., 1300 g of butadiene was added successively at 10 ml / min while the polymerization temperature was controlled to 50° C. under stirring conditions. After the addition of butadiene, the mixture was heated for 1 hour to terminate the polymerization.

[0203] (Process (2))

[0204] After adding 2.06 g of TMEDA to the polymer solution obtained by step (1), 16.6 g of triisopropyl borate was added to introduce boric acid into the polymerization end. Ion exchange water was added to the obtained polymer solution and stirred to wash the polymer solution. After confirming that the polymer solution phase and the aqueous phase have been separated, the polymer solution phase was recovered and dried under reduced pressure at 90° C. for 12 hours to obtain a polymer composition (3) comprising a boronic acid modified polymer (A3) and a disubstituted boronic acid modified polymer (B3). The physical properties of the obtained polymer composition (3) are described in Table 2.

[0205] [Examples 4 and 6]

[0206] Boric acid-modified polymer and disubstituted boric acid-modified polymer compositions (4) and (6) were obtained in the same manner as in Example 3 except that the types and addition amounts of the compounds in each step were changed as shown in Table 1. The physical properties of the obtained polymer compositions (4) and (6) are shown in Table 2.

[0207] [Examples 5 and 7]

[0208] Boric acid-modified polymer and disubstituted boric acid-modified polymer compositions (5) and (7) were obtained in the same manner as in Example 1 except that the types and addition amounts of the compounds in each step were changed as shown in Table 1. The physical properties of the obtained polymer compositions (5) and (7) are shown in Table 2.

[0209] [Example 8]

[0210] (Process (1))

[0211] A 5 L autoclave that had been dried thoroughly was purged with nitrogen, and 1200 g of cyclohexane and 54.0 g of sec-butyllithium (10.5 mass % cyclohexane solution) were added, and after the temperature was raised to 50° C., 1640 g of isoprene was added successively at 10 ml / min while stirring so that the polymerization temperature was controlled to 50° C. After the addition of isoprene, the mixture was heated for 1 hour to terminate the polymerization.

[0212] (Process (2))

[0213] A mixture of 2.06 g of TMEDA and 16.6 g of triisopropyl borate was added to the polymer solution obtained by step (1), and boric acid was introduced into the polymerization end. Ion exchange water was added to the obtained polymer solution and stirred to wash the polymer solution. After confirming that the polymer solution phase and the aqueous phase have been separated, the polymer solution phase was recovered and dried under reduced pressure at 90° C. for 12 hours to obtain a polymer composition (8) comprising a boronic acid modified polymer (A8) and a disubstituted boronic acid modified polymer (B8). The physical properties of the obtained polymer composition (8) are described in Table 2.

[0214] [Example 9]

[0215] (Process (1))

[0216] A fully dried 5L autoclave was purged with nitrogen, and 1300 g of cyclohexane, 54.0 g of sec-butyl lithium (10.5% by mass in cyclohexane solution) and 8.0 g of tetrahydrofuran were added. After the temperature was raised to 50°C, a monomer mixed solution of 1000 g of butadiene and 377 g of isoprene was added successively under stirring conditions while controlling the polymerization temperature to 50°C, and polymerization was carried out for 1 hour.

[0217] (Process (2))

[0218] A mixture of 2.06 g of TMEDA and 16.6 g of triisopropyl borate was added to the polymer solution obtained by step (1), and boric acid was introduced into the polymerization end. Ion exchange water was added to the obtained polymer solution and stirred to wash the polymer solution. After confirming that the polymer solution phase and the aqueous phase have been separated, the polymer solution phase was recovered and dried under reduced pressure at 90° C. for 12 hours to obtain a polymer composition (9) comprising a boronic acid modified polymer (A9) and a disubstituted boronic acid modified polymer (B9). The physical properties of the obtained polymer composition (9) are described in Table 2.

[0219] [Example 10]

[0220] (Process (1))

[0221] A fully dried 5L autoclave was purged with nitrogen, and 1300 g of cyclohexane and 54.0 g of sec-butyl lithium (10.5% by mass cyclohexane solution) were added. After the temperature was raised to 50°C, 580 g of styrene was added under stirring while the polymerization temperature was controlled to 50°C to carry out polymerization. Subsequently, 8.0 g of tetrahydrofuran was added, and 1000 g of butadiene was added successively at 10 ml / min. After the addition of butadiene, the mixture was heated for 1 hour to terminate the polymerization.

[0222] (Process (2))

[0223] To the polymer solution obtained by process (1), a mixture of 2.06 g of TMEDA and 16.6 g of triisopropyl borate was added, and boric acid was introduced into the polymerization end. Ion exchange water was added to the obtained polymer solution and stirred to clean the polymer solution. After confirming that the polymer solution phase and the aqueous phase have been separated, the polymer solution phase was recovered and dried under reduced pressure at 90 ° C for 12 hours to obtain a polymer composition (10) comprising a boronic acid modified polymer (A10) and a disubstituted boronic acid modified polymer (B10) (boric acid modified conjugated diene block copolymer (A10) and a disubstituted boronic acid modified conjugated diene block copolymer (B10)). The physical properties of the obtained polymer composition (10) are described in Table 2.

[0224] [Comparative Examples 1 and 2]

[0225] Polymer compositions (11) and (12) containing a boronic acid-modified polymer and a disubstituted boronic acid-modified polymer were obtained in the same manner as in Example 1 except that the type and addition amount of the compound in each step were changed as shown in Table 1. The physical properties of the obtained polymer compositions (11) and (12) are shown in Table 2.

[0226] [Comparative Example 3]

[0227] (Process (1))

[0228] A 5 L autoclave that had been dried thoroughly was purged with nitrogen, 1200 g of cyclohexane and 54.0 g of sec-butyllithium (10.5 mass % cyclohexane solution) were added, and after the temperature was raised to 50° C., 1300 g of butadiene was added successively at 10 ml / min. After the addition of butadiene, the mixture was heated for 1 hour to terminate the polymerization.

[0229] (Process (2))

[0230] 14.2 g of methanol was added to the polymerization solution obtained by step (1) to stop the polymerization. Ion exchange water was added to the obtained polymer solution and stirred to wash the polymer solution. After confirming that the polymer solution phase and the aqueous phase had separated, the polymer solution phase was recovered and dried under reduced pressure at 90° C. for 12 hours to obtain a polymer composition (13) containing a conjugated diene polymer (13). The physical properties of the obtained polymer composition (13) are described in Table 2.

[0231] [Comparative Example 4]

[0232] (Process (1))

[0233] A 5L autoclave that had been dried thoroughly was purged with nitrogen, and 1200 g of cyclohexane, 54.0 g of sec-butyl lithium (10.5% by mass cyclohexane solution), and 3.1 g of 2,2-ditetrahydrofuryl propane were added. After the temperature was raised to 50° C., 1300 g of butadiene was added successively at 10 ml / min while the polymerization temperature was controlled to 50° C. under stirring conditions. After the addition of butadiene, the mixture was heated for 1 hour to terminate the polymerization.

[0234] (Process (2))

[0235] 27.6 g of phenylboric anhydride was added to the polymer solution obtained by step (1), and a disubstituted boric acid was introduced into the polymerization terminal. Ion exchange water was added to the obtained polymer solution and stirred to wash the polymer solution. After confirming that the polymer solution phase and the aqueous phase have been separated, the polymer solution phase was recovered and dried under reduced pressure at 90° C. for 12 hours, thereby obtaining a polymer composition (14) containing a disubstituted boric acid-based modified polymer (B14). The physical properties of the obtained polymer composition (14) are described in Table 2.

[0236] [Table 1]

[0237]

[0238] Table 2 shows the physical properties of the polymer compositions obtained in Examples 1 to 10 and Comparative Examples 1 to 4.

[0239]

[0240] According to Table 2, by reacting the boronic acid compounds having substituents with a Taft stereo parameter Es value of less than -0.30 shown in Examples 1 to 10, a modified polymer having a high functional group introduction rate and being able to take into account both reactivity with polar functional groups and heat resistance is obtained. On the other hand, in Comparative Examples 1 and 2 in which boronic acid compounds having substituents with a Taft stereo parameter Es value exceeding -0.30 are reacted, the functional group introduction rate is low and the reactivity is poor. In addition, in Comparative Example 3 in which the boronic acid compound is not reacted, no reaction occurs with the polar functional group. Furthermore, in Comparative Example 4 containing only a disubstituted boronic acid compound, the reactivity is excellent, but the heat resistance is poor, and it is difficult to take into account both reactivity and heat resistance.

[0241] Industrial Applicability

[0242] By the production method of the present invention, a boronic acid modified polymer (A) suitable for modification of polar materials, dispersion of inorganic materials, etc. is obtained in high yield. In addition, a polymer composition containing the boronic acid modified polymer and the disubstituted boronic acid modified polymer obtained in the present invention in a specific ratio takes into account high reactivity and excellent storage stability for polar functional groups, and a resin composition containing the polymer composition and its polymer can be effectively used in a wide range of fields such as automotive interior and exterior packaging products, electrical / electronic components, packaging materials, sporting goods, daily necessities, laminated materials, telescopic materials, various rubber products, medical supplies, various adhesives, various coating primers, etc.

Claims

1. A method for producing a polymer composition comprising a modified polymer having a boron-containing functional group, comprising: Step (1), producing an active terminal polymer (Z) by anionically polymerizing at least one monomer selected from a conjugated diene and an aromatic vinyl compound in the presence of an anionically polymerizable active metal or active metal compound; as well as Step (2), reacting the active terminal polymer (Z) obtained in step (1) with a boronic acid compound, wherein the boronic acid compound has at least two partial structures represented by the following formula (I), and the Taft stereo parameter Es value of at least one R bonded to the oxygen atom contained in the partial structure is less than -0.30, BOR(I) In formula (I), B represents a boron atom, O represents an oxygen atom, and R represents an organic group.

2. The method for producing a polymer composition according to claim 1, wherein: In step (2), the boronic acid compound is mixed with a polar compound and then added to the active terminal polymer (Z) to allow the mixture to react.

3. A polymer composition comprising: 55 to 99% by mass of at least one boric acid-based modified polymer (A) selected from a modified polymer containing a boronic acid group represented by the following formula (II), a modified polymer containing a borate ester group represented by the following formula (III), and a modified polymer containing a borate salt represented by the following formula (IV); and 1 to 45% by mass of at least one disubstituted boronic acid-based modified polymer (B) selected from the group consisting of a modified polymer containing a disubstituted boronic acid group represented by the following formula (V) or (VI), a modified polymer containing a disubstituted boronic acid ester group represented by the following formula (VII) or (VIII), and a modified polymer containing a disubstituted boric acid salt represented by the following formula (IX) or (X); [Chemistry 1] In the above formula, P 1 , P 2 and P 3 It means a polymer chain comprising at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit; R 1 and R 2 Each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and R 1 and R 2 At least one of them is an alkyl group having 1 to 12 carbon atoms, or R 1 With R 2 bonded to form an alkylene chain having 2 to 24 carbon atoms; R 3 , R 4 and R 5 Each independently represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or a polymer chain containing at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit, and R 3 , R 4 and R 5 At least one of them is an alkyl group having 1 to 12 carbon atoms, or a polymer chain containing at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit, or R 3 With R 4 , R 3 With R 5 , or R 4 With R 5 optionally bonded to form an alkylene chain having 2 to 24 carbon atoms, R 3 , R 4 and R 5 Optionally bonded to form a trivalent saturated hydrocarbon chain having 3 to 36 carbon atoms; M represents an alkali metal or 1 / 2 alkaline earth metal, [Chemistry 2] In the above formula, P 4 , P 5 , P 6 , P 7 , P 8 , P 9 , P 10 , P 11 and P 12 It means a polymer chain comprising at least one monomer unit selected from a conjugated diene unit and an aromatic vinyl compound unit; R 6 , R 7 , R 8 , R 9 Each independently represents an alkyl group having 1 to 12 carbon atoms; R 10 and R 11 are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, R 10 and R 11 At least one of them is an alkyl group having 1 to 12 carbon atoms, or R 10 With R 11 bonded to form an alkylene chain having 2 to 24 carbon atoms; R 12 represents an alkyl group having 1 to 12 carbon atoms; R 13 and R 14 are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, R 13 and R 14 At least one of them is an alkyl group having 1 to 12 carbon atoms, or R 13 With R 14 bonded to form an alkylene chain having 2 to 24 carbon atoms; M represents one alkali metal or one-half alkaline earth metal.

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