JP6766438B2 - Modified agent, modifier composition, modified polymer and method for producing the same. - Google Patents

Description

The present invention relates to a modifier, a modifier composition, a modified polymer and a method for producing the same.

Conventionally, as a polymer contained in a rubber composition used for a tire or the like, a modified polymer modified with various nitrones is known (for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2014-101400

Under these circumstances, when the diene rubber was modified with a nitron compound with reference to Patent Document 1, it became clear that when modifying a diene rubber other than natural rubber, the modification rate may be low if the modification time is short. It was.
Further, it has been clarified that the conventional nitrone compound does not easily modify natural rubber, and the productivity of the modified polymer may be low.
Therefore, an object of the present invention is to provide a modifier (nitrone compound) having excellent productivity of a modified polymer.
It is also an object of the present invention to provide a modifying agent composition, a modified polymer and a method for producing the modified polymer.

As a result of diligent research to solve the above problems, the present inventors have found that a desired effect can be obtained by a predetermined modifier, and have arrived at the present invention.
The present invention is based on the above findings and the like, and specifically solves the above problems by the following configurations.

1. 1. A modifier that modifies a polymer that has an ester group and a nitrone bond and has an unsaturated bond.
2. The modifier according to 1 above, wherein an aromatic hydrocarbon group is bonded to the nitrogen atom of the nitrone bond.
3. 3. The modifier according to 1 or 2 above, wherein an aromatic hydrocarbon group is bonded to the nitrogen atom and the carbon atom of the nitrone bond.
4. The modifier according to any one of 1 to 3 above, wherein an aliphatic hydrocarbon group is bonded to an oxygen atom of the ester group.
5. The modifier according to any one of 1 to 4 above, wherein a tertiary alkyl group is bonded to the oxygen atom of the ester group.
6. The modifier according to any one of 1 to 5 above, wherein the number of ester groups in one molecule is plural.
7. The denaturant according to any one of 1 to 6 above, wherein the number of the nitrone bonds is 1 in one molecule.
8. The modifier according to any one of 1 to 7 above, which is a compound represented by the following formula (I).

In formula (I), R ¹¹ and R ¹² are independently hydrocarbon groups, a1 and a2 are independently 0 to 2, and a1 + a2 are 1 to 4.
9. A denaturing agent composition containing the denaturing agent according to any one of 1 to 8 above and synthetic zeolite.
10. A modified polymer having a modifying group formed by the modifying agent according to any one of 1 to 8 above.
11. At least one selected from the group consisting of a main chain and a side chain has the above-mentioned modifying group, the modifying group of the main chain is a group represented by the following formula (II), and the modifying group of the side chain is described below. The modified polymer according to 10 above, which is a group represented by the formula (III).

In the above formula (II), R ²¹ and R ²² are independently hydrocarbon groups, a21 and a22 are independently 0 to 2, and a21 + a22 are 1 to 4.

In the above formula (III), R ³¹ and R ³² are independently hydrocarbon groups, a31 and a32 are independently 0 to 2, and a31 + a32 are 1 to 4.
12. 10. The modified polymer according to 10 or 11 above, wherein the main chain is at least one selected from the group consisting of styrene-butadiene rubber, butadiene rubber, isoprene rubber, acrylic butadiene rubber and natural rubber.
13. The modified polymer according to any one of 10 to 12 above, which further has an unsaturated bond.
14. 13. The modified polymer according to 13 above, wherein the content of the modifying group is 0.01 to 2 mol% with respect to the total amount of the modifying group and the unsaturated bond.
15. The modified polymer according to any one of 10 to 14 is produced by reacting a raw material polymer having an unsaturated bond with the modifying agent according to any one of 1 to 8 or the modifying agent composition according to 9. A method for producing a modified polymer.

The modifier of the present invention is excellent in the productivity of the modified polymer.
According to the present invention, it is possible to provide a modifier composition, a modified polymer, and a method for producing the same.

FIG. 1 is a ¹ H-NMR spectrum of a compound represented by the formula (IV-4-1). FIG. 2 is a ¹³ C-NMR spectrum of the compound represented by the formula (IV-4-1).

The present invention will be described in detail below.
In the present specification, (meth) acrylate represents acrylate or methacrylate, (meth) acryloyl represents acryloyl or methacryloyl, and (meth) acrylic represents acrylic or methacrylic.
In addition, the numerical range represented by using "~" in the present specification means a range including the numerical values before and after "~" as the lower limit value and the upper limit value.
In the present specification, when the component contains two or more kinds of substances, the content of the above component means the total content of the two or more kinds of substances.
In the present specification, superiority in the productivity of the modified polymer may be referred to as "excellent in the effect of the present invention".

[Denaturant]
The modifier of the present invention is a compound having an ester group and a nitrone bond (ester nitrone compound).
(Degeneration)
The modifier of the present invention can modify (specifically, ester modify) a polymer having an unsaturated bond. That is, the modifier of the present invention can introduce an ester group into the polymer.
(Reaction between a polymer having an unsaturated bond and the denaturant of the present invention)
In the present invention, when a polymer having an unsaturated bond is reacted with the modifier of the present invention, the unsaturated bond of the polymer reacts with the nitrone bond of the modifier of the present invention, thereby esterifying the polymer. The group can be introduced. The ester group is derived from the modifier of the present invention.
(Denatured group)
In the present invention, a modifying group having a ring such as an isooxazolidine ring can be formed on a polymer having an unsaturated bond by the reaction between the unsaturated bond and the nitrone bond. The modifying group has an ester group in addition to the ring. The ester group is derived from the modifier of the present invention.
(Modified polymer)
In the present invention, the modified polymer of the present invention has a modifying group (for example, a modifying group having a ring and an ester group as described above) formed by the modifying agent of the present invention.
The modified polymer of the present invention can be obtained by reacting the modifying agent of the present invention with a polymer having an unsaturated bond.
(Unsaturated bond)
In the present invention, an unsaturated bond in a polymer having an unsaturated bond means an unsaturated carbon-carbon bond. Examples of the unsaturated bond include a double bond and a triple bond, and the double bond is one of the preferred embodiments.

Since the modifier of the present invention has such a structure, it is considered that a desired effect can be obtained. The reason is not clear, but it is presumed to be as follows.
Conventionally, nitrone compounds having no functional group such as diphenylnitrone have a low denaturation rate.
Further, when a nitrone compound having a functional group other than the nitrone bond is used for modifying the diene rubber, the modification rate may be low. This is because the conventional nitrone compound having a functional group has a high melting point, and the nitrone compound does not melt in the system and is difficult to react unless the modification temperature is raised, and the raw material polymer may gel under high temperature conditions. It was thought that there was a cause.

On the other hand, the modifier of the present invention was excellent in the productivity of the modified polymer. It was speculated that this was because the melting point of the nitrone compound could be significantly lowered by introducing an ester group into the nitrone compound, or it became easier to dissolve in the raw material polymer. Therefore, even at the same degree of denaturation temperature as before, the denaturant of the present invention is more easily dissolved in the system than the conventional nitrone compound, and even if the denaturation time is shorter than before, the denaturation rate with the raw material polymer. Is thought to have increased.

Furthermore, natural rubber was difficult to denature with conventional nitrone compounds. In the present invention, the natural rubber could be efficiently modified by reacting the natural rubber with the modifier of the present invention.
As described above, the modifier of the present invention has a predetermined functional group and has a low melting point, or is easily dissolved in the raw material polymer, so that the productivity of the modified polymer (for example, diene rubber other than natural rubber) Is excellent in the modification rate even if the modification time is shortened. Natural rubber can be efficiently modified. Etc.).
Hereinafter, the denaturant of the present invention will be described in detail.

<Ester group>
The modifier of the present invention has an ester group. The ester group is a group represented by -CO-O-.

The ester group can be bonded to the organic group (R) at the oxygen atom of the ester group.
(R: Organic group)
The organic group is not particularly limited. For example, a hydrocarbon group can be mentioned.
Examples of the hydrocarbon group include an aliphatic hydrocarbon group (including linear, branched, and cyclic), an aromatic hydrocarbon group, or a combination thereof. The hydrocarbon group may have an unsaturated bond.
The carbon number of the hydrocarbon group as R is preferably 20 or less, more preferably 1 to 15, further preferably 3 to 15, particularly preferably 4 to 12, from the viewpoint of being more excellent in the effect of the present invention.

As the hydrocarbon group as R, an aliphatic hydrocarbon group is preferable, a chain aliphatic hydrocarbon group is more preferable, and a tertiary alkyl group is further preferable, from the viewpoint of being more excellent in the effect of the present invention. The tertiary alkyl group is an alkyl group having a tertiary carbon atom.

Examples of the hydrocarbon group as R include aliphatic hydrocarbon groups such as methyl group, ethyl group, butyl group, pentyl group, hexyl group, octyl group, decyl group and dodecyl group.
Examples of the tertiary alkyl group include a tert-butyl group, a tert-pentyl group and a tert-hexyl group.

The modifier of the present invention has one or more ester groups in one molecule. The number of ester groups is preferably a plurality in one molecule of the modifier, and more preferably 2 to 4 from the viewpoint of being more excellent in the effect of the present invention.
In the present specification, a nitrone compound having one ester group in one molecule may be referred to as a monoester nitrone compound. A nitrone compound having a plurality of ester groups may be referred to as a polyester nitrone compound, and a nitrone compound having two ester groups may be referred to as a diester nitrone compound.

<Nitrone bond>
The denaturant of the present invention has a nitrone bond. The nitrone bond is a group represented by the following formula (1).

In equation (1), * represents the bond position.
In the present specification, the nitrone bond may be expressed as −N (= O) = CH−.

The denaturant of the present invention can have 1 to 3 nitrone bonds in one molecule. The number of nitrone bonds in one molecule of the modifier of the present invention is preferably one from the viewpoint of being superior to the effect of the present invention.

(Organic group via ester group and nitrone bond)
The ester group (for example, the carbon atom of the ester group) and the nitrone bond can be bonded via an organic group.
The organic group is not particularly limited. For example, a hydrocarbon group which may have a hetero atom can be mentioned.

The hydrocarbon group is the same as above. Of these, an aromatic hydrocarbon group is preferable, and a benzene ring is more preferable.

Examples of the hetero atom that the organic group may have include an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen. A hetero atom may be bonded to another hetero atom, carbon atom or hydrogen atom to form a functional group.
One of the preferred embodiments is that the modifier of the present invention does not have the above functional groups.
When the modifier of the present invention further has the above functional groups, the number of functional groups can be 1 to 6 in one molecule of the modifier.

(Aromatic hydrocarbon group)
In the modifier of the present invention, it is preferable that an aromatic hydrocarbon group is bonded to a nitrogen atom and / or a carbon atom of a nitrone bond, and an aromatic hydrocarbon group may be bonded to a nitrogen atom and a carbon atom of a nitrone bond, respectively. More preferred.
The aromatic hydrocarbon group is not particularly limited. For example, a benzene ring can be mentioned.

Examples of the modifier of the present invention include compounds represented by the following formula (I).

In formula (I), R ¹¹ and R ¹² are each independently preferably having a hydrocarbon group.
a1 and a2 are 0 to 2 independently of each other.
a1 + a2 are 1 to 4.
The hydrocarbon groups as R ¹¹ and R ^{12 are the same} as those of R above. Independently, R ¹¹ and R ¹² are preferably an aliphatic hydrocarbon group, and more preferably a tertiary alkyl group.

A case where a1 is 1 and a2 is 0, or a case where a1 and a2 are 1 is mentioned as a preferable embodiment.

Specific examples of the denaturing agent include monoester nitrone compounds represented by the following formulas (IV-1) to (IV-3); and diester nitrone compounds represented by the following formula (IV-4). Be done.

The melting point of the modifier of the present invention is preferably 80 to 230 ° C. The melting point of the modifier of the present invention can be measured according to JIS 0064-1992 (visual melting point measuring method).

(Manufacturing method of denaturant)
Examples of the method for producing the modifier of the present invention include method 1 in which a carboxynitrone compound having a carboxy group and a nitrone bond is reacted with a hydroxy group-containing compound.

-Carboxynitrone compound The carboxynitrone compound that can be used in the method for producing a modifier of the present invention (method 1 above) is a compound having a carboxy group (-COOH) and a nitrone bond.

The carboxy group and the nitrone bond can be bonded via an organic group.
The organic group is not particularly limited. For example, it is the same as the above-mentioned organic group via an ester group and a nitrone bond. Of these, aromatic hydrocarbon groups are preferable. The aromatic hydrocarbon group is the same as above.

The carboxynitrone compound preferably has an aromatic hydrocarbon group bonded to a nitrogen atom and / or a carbon atom of a nitrone bond, and more preferably an aromatic hydrocarbon group bonded to a nitrogen atom and a carbon atom of a nitrone bond, respectively.

Examples of the carboxylinitron compound include a compound represented by the following formula (3).

In formula (3), m and n are 0 to 2 independently.
The sum of m and n is 1 to 4.
X represents a hydrogen atom.

Specific examples of the carboxynitrone compound include carboxynitrone compounds represented by the following formulas (3-1) to (3-6).

-Hydroxy group-containing compound The hydroxy group-containing compound that can be used in the method for producing the modifier of the present invention (method 1 above) is a compound having a hydroxy group.
The group to which the hydroxy group is attached is not particularly limited. For example, an organic group can be mentioned. The organic group is the same as the organic group R bonded to the oxygen atom of the ester group.

The number of hydroxy groups contained in one molecule of the hydroxy group-containing compound is not particularly limited. One of the preferred embodiments is that one molecule of the hydroxy group-containing compound has one hydroxy group.

Examples of the hydroxy group-containing compound include alcohol. Alcohol is an aliphatic hydrocarbon compound having a hydroxy group. Examples of the alcohol include methanol, ethanol, butanol, hexanol, and octanol.
The alcohol is preferably tertiary alcohol. Examples of the tertiary alcohol include tert-butanol, tert-pentanol, and tert-hexanol.

The amount of the carboxynitrone compound and the hydroxy group-containing compound used is such that the molar ratio (OH / COOH) of the hydroxy group of the hydroxy group-containing compound to the carboxy group of the carboxynitrone compound is 1.0 to 2.5. Can be.

For the reaction between the carboxylinitron compound and the hydroxy group-containing compound, for example, it is preferable to further use a catalyst such as N, N-dimethyl-4-aminopyridine as one of the preferred embodiments. The amount of the catalyst used is not particularly limited.

For the reaction between the carboxylinitron compound and the hydroxy group-containing compound, for example, it is preferable to further use a carbodiimide such as dicyclohexylcarbodiimide as one of the preferred embodiments. The carboxylinitron compound and the carbodiimide are coupled to form an ester, and the ester and the hydroxy group-containing compound undergo a transesterification reaction to produce the modifier of the present invention.
The amount of carbodiimide used can be 0.8 to 1.5 mol with respect to 1 mol of the carboxy group contained in the carboxynitrone compound.

The temperature of the reaction can be 0 to 30 ° C.
In addition, the above reaction can be carried out in a solvent. The solvent is not particularly limited as long as it is inert to the above reaction. For example, an organic solvent such as dichloromethane can be used.
The denaturant of the present invention may be purified after all reactions have been completed. The purification method is not particularly limited.

As a method for producing the modifier of the present invention, which is different from the above method 1, for example, a method 2 in which a compound having a hydroxyamino group (-NHOH) and a compound having an aldehyde group (-CHO) are reacted can be mentioned. Be done. At this time, either one or both of the compound having a hydroxyamino group and the compound having an aldehyde group may have an ester group.
Specifically, in the above method 2, for example, a compound having a hydroxyamino group (-NHOH) and a compound having an aldehyde group (-CHO) are mixed with each other in a molar ratio of a hydroxyamino group to an aldehyde group (-NHOH / −). By stirring at room temperature for 1 to 24 hours under an organic solvent (for example, methanol, ethanol, tetrahydrofuran, etc.) in an amount of CHO) of 1.0 to 1.5, both groups react with each other, and the ester group and the ester group and A compound having a nitron group can be produced.

(Ingredient polymer)
The polymer having an unsaturated bond (for example, a double bond) (raw material polymer) to which the modifier of the present invention is applied is not particularly limited.

Examples of the raw material polymer having an unsaturated bond include diene-based rubber. Specific examples thereof include natural rubber (NR) (NR includes deproteinized natural rubber), isoprene rubber (IR), butadiene rubber (BR), and aromatic vinyl-conjugated diene copolymer rubber (for example). Styrene-butadiene rubber (SBR)), acrylonitrile-butadiene copolymer rubber (NBR), butyl rubber (IIR), halogenated butyl rubber (Br-IIR, Cl-IIR), chloroprene rubber (CR) and the like.
Of these, butadiene rubber, aromatic vinyl-conjugated diene copolymer rubber, and natural rubber are preferable.

[Denaturant composition]
The modifier composition of the present invention is a modifier composition containing the modifier of the present invention and synthetic zeolite.
Since the modifier composition of the present invention contains the modifier of the present invention, it is possible to modify a polymer having an unsaturated bond.

The raw material polymer to which the modifying agent of the present invention or the modifying agent composition of the present invention is applied may contain impurities. When the raw material polymer is natural rubber, examples of impurities contained in the natural rubber include proteins. The present inventors have found that impurities as described above may decompose the modifier of the present invention, thereby reducing the productivity of the modified polymer.
In response to such problems, the present inventors have found that the modifier composition of the present invention contains synthetic zeolite, whereby the synthetic zeolite adsorbs impurities contained in the raw material polymer. In this way, the impurities contained in the raw material polymer are inactivated by the synthetic zeolite to prevent the modifier of the present invention from being decomposed by the impurities, thereby increasing the reaction efficiency of the modifier of the present invention and modifying it. It is presumed that the polymer can be produced more efficiently.

<Denaturant>
The modifier contained in the modifier composition of the present invention is not particularly limited as long as it is the modifier of the present invention.

<Synthetic zeolite>
The synthetic zeolite contained in the modifier composition of the present invention is not particularly limited.
Specific examples of synthetic zeolites, _{e.g., Na 2 O · Al 2 O} 3 · 2SiO 2 · sH 2 O (2 ≦ s ≦ 7), Na 2 O · Al 2 O 2 · 3SiO 2 · sH 2 O (2 ≦ s ≦ 7), aluminosilicates such as _{CaO · Al 2 O 2 · 3SiO} 2 · sH 2 O (2 ≦ s ≦ 7) can be mentioned.

The synthetic zeolite is preferably a powder.
The average particle size of the synthetic zeolite is preferably 10 μm or less.
In the present invention, the average particle size of the synthetic zeolite can be obtained by measuring the volume-based particle size distribution using a laser diffraction type particle size distribution measuring device, and is the particle size at a cumulative 50% (50% volume cumulative diameter). Say. Examples of such a laser diffraction type particle size distribution measuring device include a device conforming to LA-500 (trade name) manufactured by HORIBA, Ltd.

The synthetic zeolite is not particularly limited in its production method. For example, conventionally known ones can be mentioned. Synthetic zeolites can be used alone or in combination of two or more.

The mass ratio of the synthetic zeolite to the modifier of the present invention (synthetic zeolite / modifier of the present invention) is preferably 2.0 to 30, more preferably 2 to 15.

The polymer modifier composition of the present invention may further contain additives. Examples of the additive include a denaturant other than the denaturant of the present invention and an inorganic substance other than synthetic zeolite.
Further, the polymer modifier composition of the present invention may contain only a nitrone compound and a synthetic zeolite.

The polymer modifier composition of the present invention is not particularly limited in its production method. For example, it can be produced by mixing the modifier of the present invention, synthetic zeolite, and an additive that can be used as needed.

The (raw material) polymer to which the polymer modifier composition of the present invention can be applied is not particularly limited as long as it has an unsaturated bond. For example, the same as above can be mentioned.
The (raw material) polymer to which the modifier composition of the present invention can be applied is a natural rubber which may contain, for example, a protein as an impurity from the viewpoint that the synthetic zeolite can remove a protein derived from the natural rubber. Is mentioned as one of the preferred embodiments.

[Modified polymer]
The modified polymer of the present invention is a modified polymer having a modifying group formed by the modifying agent of the present invention.

<Denatured group>
One of the preferred embodiments is that the modified polymer of the present invention has a modifying group in at least one selected from the group consisting of a main chain and a side chain.
Further, one of the preferred embodiments is that at least a part of the main chain or at least a part of the side chain of the modified polymer of the present invention has a modifying group.

Examples of the modifying group contained in the main chain include a group represented by the following formula (II).
Examples of the modifying group contained in the side chain include a group represented by the following formula (III).

In the above formula (II), R ²¹ and R ²² are preferably independent hydrocarbon groups, more preferably aliphatic hydrocarbon groups, and even more preferably tertiary alkyl groups.
a21 and a22 are 0 to 2 independently of each other.
a21 + a22 are 1 to 4.
A case where a21 is 1 and a22 is 0, or a case where a21 and a22 are 1 is mentioned as a preferable embodiment.

Formula ^{(II), R 21, R} 22, a21, a22, a21 + a22 , respectively, the formula (I), is the same as ^{R 11, R 12, a1,} a2, a1 + a2. R ¹¹ corresponds to R ²¹ and R ¹² corresponds to R ²² .

In the above formula (III), R ³¹ and R ³² are each independently preferably a hydrocarbon group, more preferably an aliphatic hydrocarbon group, and even more preferably a tertiary alkyl group.
a31 and a32 are 0 to 2 independently of each other.
a31 + a32 are 1 to 4.
A case where a31 is 1 and a32 is 0, or a case where a31 and a32 are 1 is mentioned as a preferable embodiment.
R ³¹ , R ³² , a31, a32, and a31 + a32 of the formula (III) are the same as R ¹¹ , R ¹² , a1, a2, and a1 + a2 of the formula (I), respectively. R ¹¹ corresponds to R ³¹ and R ¹² corresponds to R ³² .

The main chain of the modified polymer of the present invention is preferably at least one selected from the group consisting of styrene-butadiene rubber, butadiene rubber, isoprene rubber, acrylic butadiene rubber, acrylonitrile-butadiene rubber and natural rubber.

The modified polymer of the present invention preferably has an unsaturated bond (for example, a double bond). Unsaturated bonds (eg, double bonds) may be in the main chain, side chain or terminal.

The content (modification rate) of the modifying group may be 0.01 to 2 mol% with respect to the total amount of the modifying group and the unsaturated bond (for example, double bond) of the modified polymer of the present invention. Preferably, 0.05 to 1.5 mol% is more preferable.
When the main chain of the modified polymer is natural rubber, the content of the modifying group is 0.01 to 2 mol with respect to the total amount of the modified group and the unsaturated bond (for example, double bond) of the modified polymer. %, More preferably 0.05 to 1.5 mol%.
When the main chain of the modified polymer is other than natural rubber, the content of the modifying group is 0.01 to 2 with respect to the total amount of the modified group and the unsaturated bond (for example, double bond) of the modified polymer. It is preferably mol%, more preferably 0.05 to 1.5 mol%, still more preferably 0.1 to 1.5 mol%.

[Manufacturing method of modified polymer]
The method for producing a modified polymer of the present invention comprises reacting a raw material polymer having an unsaturated bond (for example, a double bond) with the modifying agent of the present invention or the modifying agent composition of the present invention to obtain the modified polymer of the present invention. It is a method for producing a modified polymer. The modifier of the present invention or the modifier composition of the present invention used in the method for producing a modified polymer of the present invention may be referred to as "modified agent or the like". Further, the denaturing agent contained in the denaturing agent composition of the present invention has the same meaning as the denaturing agent of the present invention.

<Ingredient polymer>
The raw material polymer used in the method for producing a modified polymer of the present invention is not particularly limited as long as it is a polymer having an unsaturated bond (for example, a double bond). For example, a diene rubber can be mentioned.
Among them, at least one selected from the group consisting of styrene-butadiene rubber, butadiene rubber, isoprene rubber, acrylic butadiene rubber, acrylonitrile-butadiene rubber and natural rubber is preferable.
The weight average molecular weight of the raw material polymer is not particularly limited.
The raw material polymers can be used alone or in combination of two or more.

(Denaturant)
The modifier that can be used in the method for producing the modified polymer of the present invention is not particularly limited as long as it is the modifier of the present invention.
The denaturants can be used alone or in combination of two or more.

The amount of the modifier used is preferably 0.1 to 5.0 parts by mass, more preferably 1.0 to 3.0 parts by mass with respect to 100 parts by mass of the raw material polymer.

(Denaturant composition)
The modifier composition that can be used in the method for producing the modified polymer of the present invention is not particularly limited as long as it is the modifier composition of the present invention.
The denaturing agent composition can be used alone or in combination of two or more.

The amount of the modifier composition used is preferably 0.5 to 25 parts by mass, more preferably 0.5 to 20 parts by mass, still more preferably 1 to 15 parts by mass with respect to 100 parts by mass of the raw material polymer.

By the above reaction, the insatiable bond (for example, double bond) of the raw material polymer is modified by the modifier of the present invention. A modifying group can be formed by the above-mentioned insatiability bond and the modifying agent of the present invention. The modifying group can have an ester group.
0.01 to 2 mol% of the unsaturated bonds of the raw material polymer are preferably modified with the modifier of the present invention, more preferably 0.05 to 1.5.
When the raw material polymer is natural rubber, 0.01 to 2 mol% of the unsaturated bonds of the raw material polymer are preferably modified with the modifier of the present invention, and 0.05 to 1.5 mol% is More preferred.
When the raw material polymer is other than natural rubber, 0.01 to 2 mol% of the unsaturated bonds of the raw material polymer is preferably modified with the modifier of the present invention, and 0.05 to 1.5 mol%. Is more preferable, and 0.1 to 1.5 mol% is further preferable.

When the unsaturated bond of the raw material polymer in the main chain is a double bond, the nitrone bond of the modifier of the present invention can react with the double bond, for example, represented by the following formula (4).

When the unsaturated bond of the raw material polymer in the side chain is a double bond, the nitrone bond of the modifier of the present invention can react with the double bond, for example, represented by the following formula (5).

By mixing the raw material polymer with a modifier or the like and heating the mixture, the unsaturated bond of the raw material polymer can be modified to produce the modified polymer of the present invention. A modifying group having an ester group can be formed by the reaction between the unsaturated bond of the raw material polymer and the modifying agent of the present invention.
The temperature at the time of denaturation (denaturation temperature) can usually be 130 to 200 ° C., preferably 150 ° C. or higher.
When the raw material polymer is a diene-based rubber other than natural rubber (for example, styrene-butadiene rubber or butadiene rubber), the modification temperature is preferably 160 to 170 ° C.
When the raw material polymer is natural rubber, the denaturation temperature is preferably 170 ° C. or lower.
The modified polymer of the present invention may contain an unreacted modifier.

The use of the modified polymer of the present invention is not particularly limited. For example, it can be used for rubber compositions.

The present invention will be specifically described below with reference to examples. However, the present invention is not limited to these.
(Synthesis of carboxylinitron compound)
Methanol (900 mL) warmed to 40 ° C. was placed in a 2 L eggplant flask, and terephthalic acid (30.0 g) represented by the following formula (3) was added thereto and dissolved. A solution of phenylhydroxyamine (21.8 g) represented by the following formula (2) in methanol (100 mL) was added to this solution, and the mixture was stirred at room temperature for 19 hours. After completion of stirring, a carboxynitrone compound (N-phenyl-α- (4-carboxyphenyl) nitrone) represented by the following formula (4) was obtained by recrystallization from methanol (41.7 g). The yield was 86%.

<Manufacturing of denaturant>
(Denaturant 1)
First, in a 200 mL eggplant flask, 12 g of the carboxylinitron compound synthesized as described above, 0.72 g of dimethylaminopyridine (manufactured by Tokyo Kasei Co., Ltd.) and the hydroxy group-containing compound 1 shown below were added to CH ₂ Cl ₂ (Kanto Chemical Co., Inc.). Manufactured) Dissolved in 120 mL to prepare a mixed solution.

-Hydroxy group-containing compound 1: Methanol (manufactured by Tokyo Kasei Co., Ltd.) 1.9 g

Next, while stirring the mixed solution, 13.2 g of dicyclohexylcarbodiimide (manufactured by Kanto Chemical Co., Inc.) was added little by little over 5 minutes to the mixed solution. Then, the mixture was stirred at room temperature for 3 days to react N-phenyl-α- (4-carboxyphenyl) nitrone with the hydroxy group-containing compound 1.
After the reaction is completed, the reaction solution is filtered through silica gel, the solid obtained by filtration is washed with ethyl acetate, and finally the solvent is distilled off to obtain the desired denaturant 1 (formula (IV-1-1) below). ) Was obtained.

The chemical shift of ¹ H-NMR (nuclear magnetic resonance) of the denaturing agent 1 was as follows.
δ (ppm) (solvent CDCl ₃ , 400 MHz, standard substance TMS: tetramethylsilane): 8.47 (2H, d), 8.15 (2H, d), 8.01 (1H, s), 7.80 (2H, m), 7.53 ( 3H, m), 3.98 (3H, s)

The melting point of the modifier 1 was 160 ° C.

(Denaturant 2)
The compound was synthesized in the same manner as the denaturant 1 except that the hydroxy group-containing compound 1 was replaced with 2.7 g of the hydroxy group-containing compound 2: ethanol (manufactured by Tokyo Kasei Co., Ltd.), and represented by the following formula (IV-2-1). Denaturer 2 was obtained.

The chemical shift of ¹ H-NMR of denaturant 2 was as follows.
δ (ppm) (solvent CDCl ₃ , 400 MHz, standard substance TMS: tetramethylsilane): 8.43 (2H, d), 8.20 (2H, d), 8.01 (1H, s), 7.90 (2H, m), 7.54 (3H, m), 4.43 (2H, q), 1.44 (3H, t)

The melting point of the denaturant 2 was 164 ° C.

(Denaturant 3)
The compound was synthesized in the same manner as the denaturant 1 except that the hydroxy group-containing compound 1 was replaced with 4.2 g of the hydroxy group-containing compound 3: tert-butanol (manufactured by Tokyo Kasei Co., Ltd.), and represented by the following formula (IV-3-1). The denaturing agent 3 to be obtained was obtained.

The ¹ H-NMR chemical shift of denaturant 3 was as follows.
δ (ppm) (solvent CDCl ₃ , 400 MHz, standard substance TMS: tetramethylsilane): 8.45 (2H, d), 8.09 (2H, d), 8.00 (1H, s), 7.80 (2H, m), 7.52 ( 1H, m), 3.15 (2H, t), 1.78 (2H, m), 1.27 (18H, m), 0.87 (3H, t)

The melting point of the denaturant 3 was 166 ° C.

(Denaturant 4)
The denaturant 4 (compound represented by the formula (IV-4-1)) was synthesized according to the following scheme.

16.7 g of the compound represented by the formula (7) (manufactured by Tokyo Kasei Co., Ltd.), 14.8 g of tert-butanol (manufactured by Tokyo Kasei Co., Ltd., the same applies hereinafter), 24.8 g of N, N'-dicyclohexylcarbodiimide (DCC) (Kanto). Chemical Co., Ltd., the same applies hereinafter) and dimethylaminopyridine (DMAP): 6.1 g (manufactured by Tokyo Kasei Co., Ltd., the same applies hereinafter) are mixed in dichloromethane as a solvent, and the mixture is reacted at room temperature to formulate (8). The compound represented by is obtained.

3.4 g of the compound represented by the formula (8), 2.0 g of zinc (manufactured by Kanto Chemical Co., Inc.) and 0.8 g of ammonium chloride (manufactured by Kanto Chemical Co., Inc.) are mixed in methanol and water as solvents, and the mixture is brought to room temperature. The reaction was carried out below to obtain a compound represented by the formula (9).

2.1 g of the compound represented by the formula (9) and 1.5 g of the terephthalic acid were mixed in methanol as a solvent, and the mixture was reacted at room temperature to obtain a compound represented by the formula (10). ..

2.4 g of the compound represented by the formula (10), 1.1 g of tert-butanol, 1.7 g of N, N'-dicyclohexylcarbodiimide (DCC) and 0.9 g of DMAP were mixed in dichloromethane as a solvent to prepare a mixture. Was reacted at room temperature to obtain a compound represented by the formula (IV-4-1). The compound represented by the formula (IV-4-1) was used as the denaturant 4.

FIG. 1 is a ¹ H-NMR spectrum of a compound represented by the formula (IV-4-1). ^{In 1 1} H-NMR measurement, CDCl ₃ was used as a solvent and tetramethylsilane was used as a standard substance, and the resonance frequency was 400 MHz.
In FIG. 1, the chemical shift around 1.4 ppm belongs to the tert-butyl group. Chemical shifts around 7.8-8.5 ppm belong to the benzene ring. The chemical shift around 8.0 ppm is attributed to the nitrone group.

FIG. 2 is a ¹³ C-NMR spectrum of the compound represented by the formula (IV-4-1). In the measurement of ¹³ C-NMR, CDCl ₃ as the solvent, CDCl ₃ is used as a standard substance, the resonance frequency was 100 MHz.
In FIG. 2, the chemical shift around 28 ppm is attributed to the tert-butyl group. Chemical shifts around 120-135 ppm belong to the benzene ring. The chemical shift around 151 ppm is attributed to the nitrone group. The chemical shift around 164 ppm is attributed to the carbonyl group.

The melting point of the compound represented by the formula (IV-4-1) was 206 to 209 ° C.

<Manufacturing of modified polymer>
Each component in Table 1 below was used in the composition (parts by mass) shown in the same table, these were mixed with a mixer, and reacted at the denaturation temperature and denaturation time shown in the same table to prepare each modified polymer. In Table 2, modified polymers were produced in the same manner as above.
In each table, the number of moles of each denaturant used and the comparative nitrone compound is the same for each table in all Examples and Comparative Examples.

<Evaluation>
The following evaluations were made for each modified polymer produced as described above. The results are shown in Tables 1 and 2.

-Modification rate of modified polymer (mol%)
The modification rate of each modified polymer obtained in the examples was determined as follows. First, ¹ H-NMR of the raw material polymer and the modified polymer was measured (solvent CDCl ₃ , 400 MHz, standard substance TMS).
Next, according to the above measurement, around 8.00 ppm (in the benzene ring which is bonded to the carbon atom derived from the nitrone bond and has an ester group, it belongs to two protons on the benzene ring adjacent to the ester group) or , 7.8 ppm (in the benzene ring that is bonded to the nitrogen atom derived from the nitrone bond and has an ester group, it belongs to two protons on the benzene ring adjacent to the ester group), and the peak area thereof was measured. From the results, the modification rate of the modified polymer was determined.
The denaturation rate obtained as described above is shown as "denaturation rate" in Tables 1 and 2. The modification rate means the content (mol%) of the modifying group in the modified polymer with respect to the total amount of the modifying group and the unsaturated bond (for example, double bond).

The modification rate of the modified polymer is the same as that of the modified polymer, except that the peak area of about 8.00 ppm or 7.8 ppm is measured as the peak area of about 8.08 ppm (belonging to two protons on the benzene ring adjacent to the carboxy group). In the same manner, the modification rate with the comparative nitrone compound (carboxy group) was determined.

・ Nitron reaction rate (mol%)
The nitrone reaction rate is the mol% of the modifier introduced into the modified polymer with respect to each modifier (comparative example is a comparative nitrone compound) reacted with the raw material polymer.

Details of each component shown in Table 1 or Table 2 are as follows.
Raw material polymer 1 (SBR): Styrene butadiene rubber produced by solution polymerization. Product name E581, manufactured by Asahi Kasei Chemicals. 37.5 parts by mass of oil spread with respect to 100 parts by mass of net SBR. Weight average molecular weight 1,200,000.
-Raw material polymer 2 (BR): butadiene rubber. Product name UBEPOL VCR412, manufactured by Ube Industries, Ltd. Weight average molecular weight 850,000.

-Raw material polymer 3 (NR); natural rubber. Raw material polymer 4 (deproteinized NR) manufactured by PT. NUSIRA (SAD); natural rubber from which protein has been removed. Product name Pureprene, manufactured by The Malaysian Rubber Board (MRB)

-Modifiers 1 to 4: Denaturers 1 to 4 manufactured as described above.

-Comparative Nitron Compound (CNP): A carboxylinitron compound produced as described above. The above carboxynitrone compound was decomposed at 240 ° C. or higher.

Synthetic zeolites 1: trade name molecular sieve 5A, Tomoe Engineering Co. Ltd., average particle diameter of 10μm or _{less, Na 2 O · Al 2 O} 3 · 2SiO 2 · sH 2 O (2 ≦ s ≦ 7)

As is clear from the results shown in Table 1, the denaturant of the present invention was able to modify a polymer having an unsaturated bond.
Comparing Example 5 with a short denaturation time and Comparative Example 2, Example 5 had a higher denaturation rate and nitrone reaction rate than Comparative Example 2, and was excellent in productivity.
Examples 1 to 4 having a denaturation time longer than that of Example 5 had a denaturation rate equal to or higher than that of Comparative Example 1 in which a carboxylinitron compound was used instead of a predetermined denaturing agent.
In Examples 1 to 3, the larger the number of carbon atoms of the hydrocarbon group bonded to the oxygen atom of the ester group of the modifier, the higher the modification rate and the nitrone reaction rate, and the higher the productivity.

Comparing Examples 1 to 3 with Example 4, the modification rate and nitrone reaction of Example 4 using the diester nitrone compound as the denaturing agent are higher than those of Examples 1 to 3 using the monoester nitrone compound as the denaturing agent. Higher rate and better productivity.

Next, in Table 1, Comparative Example 3 in which the comparative nitrone compound (CNP) was used with respect to the natural rubber could not efficiently modify the natural rubber.
On the other hand, in Examples 6 to 9 in which a predetermined modifier was used, the natural rubber could be efficiently modified, and the productivity was excellent.
In Examples 6 to 8, the modification rate and the nitrone reaction rate were higher as the number of carbon atoms of the hydrocarbon group bonded to the oxygen atom of the ester group of the modifier was larger, and the productivity was more excellent.

Comparing Examples 6 to 8 with Example 9, Example 9 using the diester nitrone compound as the denaturing agent has a higher modification rate and nitrone reaction than Examples 6 to 8 using the monoester nitrone compound as the denaturing agent. Higher rate and better productivity.
As described above, the modifier of the present invention is excellent in the productivity of the modified polymer.

As is clear from the results shown in Table 2, Example 11 using the deproteinized natural rubber was superior to Example 10 using the non-deproteinized natural rubber in the productivity of the modified polymer.
This was considered to suggest that the modifier of the present invention may be decomposed by impurities such as proteins contained in the raw material polymer.
On the other hand, when the modifying agent composition of the present invention was used as the modifying agent (Examples 12 to 15), the productivity of the modified polymer was superior to that of Example 10 in which the synthetic zeolite was not used. Examples 12 to 15 were as good as or better than Example 11 in the productivity of the modified polymer.
Further, when the modifying agent composition of the present invention was used as the modifying agent (Example 17), the productivity of the modified polymer was superior to that of Example 16 in which the synthetic zeolite was not used.
As described above, by using the modifier composition of the present invention, the productivity of the modified polymer (particularly when the raw material polymer is natural rubber) is excellent.

Claims (7)

A modifier that is a compound represented by the following formula (I) and that modifies a polymer having an unsaturated bond.
In formula (I), R ¹¹ and R ¹² are independently hydrocarbon groups, a1 and a2 are independently 0 to 2, and a1 + a2 are 1 to 4. A denaturing agent composition containing the denaturing agent according to claim 1 and synthetic zeolite. Have a modifying group that is formed by denaturing agent according to claim 1,
At least one selected from the group consisting of a main chain and a side chain has the modifying group, the modifying group of the main chain is a group represented by the following formula (II), and the modifying group of the side chain is as follows. A modified polymer which is a group represented by the formula (III) .
In the above formula (II), R ²¹ and R ²² are independently hydrocarbon groups, a21 and a22 are independently 0 to 2, and a21 + a22 are 1 to 4.
In the above formula (III), R ³¹ and R ³² are independently hydrocarbon groups, a31 and a32 are independently 0 to 2, and a31 + a32 are 1 to 4. The modified polymer according to claim 3 , wherein the main chain is at least one selected from the group consisting of styrene-butadiene rubber, butadiene rubber, isoprene rubber, acrylic butadiene rubber and natural rubber. The modified polymer according to claim 3 or 4 , further having an unsaturated bond. The modified polymer according to claim 5 , wherein the content of the modifying group is 0.01 to 2 mol% with respect to the total amount of the modifying group and the unsaturated bond. Producing modified polymer according to any one of claims 3-6 by reacting a modifier composition according to denaturants or claim 2 according to claim 1 as a raw material polymer having an unsaturated bond A method for producing a modified polymer.