JP2020164638A - Rubber or resin additive - Google Patents

Abstract

To provide a rubber or resin additive that is easy to be dispersed in rubber or thermoplastic resin and can improve tensile strength of rubber or thermoplastic resin.SOLUTION: A rubber or resin additive contains flaky carbon with a thickness of 1-100 nm, and an organic compound having a hydrophilic group and a hydrophobic group with high carbon affinity.SELECTED DRAWING: None

Description

The present invention relates to additives for rubber or resins.

In order to improve the fuel efficiency of automobiles and the performance of sports, it is desired to improve the strength and weight of composite resins and rubbers at the same time. Although the elastic modulus improves as the additive is added to the resin and rubber (see, for example, Patent Document 1), there is a problem that the flexibility is impaired and the strength is not improved or the specific gravity is increased.

On the other hand, the graphene sheet is a two-dimensional single-walled sheet in which carbon atoms are arranged in a honeycomb lattice, and is also a constituent unit of graphite, fullerenes, carbon nanotubes, and the like. The flaky carbon in which the graphene sheet is laminated to a thickness of about 100 nm or less (in the present invention, the concept including the graphene sheet) has various unique physical properties, and is therefore used for various materials. It is attracting attention as a new material.

JP-A-2015-183132

However, nanocarbon materials such as flaky carbon are more likely to aggregate as they have a finer structure, and it is difficult to fully exert their potential, and the strength cannot be sufficiently improved.

An object of the present invention is to provide an additive for rubber or resin that can be easily dispersed in rubber or thermoplastic resin and can improve the tensile strength of rubber or thermoplastic resin.

As a result of diligent research to achieve the above object, the present inventors include flaky carbon having a thickness of 1 to 100 nm and an organic compound having a hydrophilic group and a hydrophobic group having a high affinity with carbon. As a result, it has been found that an additive for rubber or resin that can be easily dispersed in rubber or thermoplastic resin and can improve the tensile strength of rubber or thermoplastic resin can be obtained. The present inventors have further studied based on the findings and have completed the present invention. That is, the present invention includes the following configurations.
Item 1. An additive for rubber or resin, which contains flaky carbon having a thickness of 1 to 100 nm and an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon.
Item 2. Item 2. Addition for rubber or resin according to Item 1, wherein 0.01 to 0.9 parts by mass of an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon is contained in 1 part by mass of the flaky carbon. Agent.
Item 3. The hydrophilic group is a general formula (1) to (4):

[In the formula, -OH represents an alcoholic hydroxyl group or a phenolic hydroxyl group. R represents a divalent organic group. X ¹ represents a hydrogen atom, alkali metal, NH ₄ or organic ammonium. X ² represents a hydrogen atom, alkali metal, NH ₄ , organic ammonium or alkyl group. The oxygen atom of the general formula (2) is an ether bond. ]
Item 3. The additive for rubber or resin according to Item 1 or 2, which is at least one kind represented by.
Item 4. Item 2. The additive for rubber or resin according to any one of Items 1 to 3, wherein the hydrophilic group is a phenolic hydroxyl group and / or a polyoxyethylene group.
Item 5. Item 2. Any one of Items 1 to 4, wherein the hydrophobic group is at least one selected from the group consisting of an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, and a polyoxyalkylene group having 3 or more carbon atoms. The described rubber or resin additive.
Item 6. Item 6. The additive for rubber or resin according to any one of Items 1 to 5, wherein the hydrophobic group is an aryl group having two or more aromatic rings.
Item 7. Item 2. The method for producing an additive for rubber or resin according to any one of Items 1 to 6.
(1) A production method comprising a step of removing a solvent from a dispersion containing the flaky carbon, the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon, and a solvent.
Item 8. Item 7. The production method according to Item 7, wherein the step of removing the solvent is a step of concentrating the dispersion.
Item 9. Item 7. The production method according to Item 7 or 8, wherein the solvent is water.
Item 10. A rubber or resin reinforced composition containing the heat conductive material according to any one of Items 1 to 6 and at least one selected from the group consisting of a thermoplastic resin, rubber and a thermoplastic elastomer.
Item 11. Item 2. The rubber or resin reinforced composition according to Item 10, wherein the thermoplastic resin, rubber and thermoplastic elastomer are aromatic polymer compounds.
Item 12. Item 10. The method for producing a rubber or resin reinforced composition according to Item 10.
(2) A production method comprising a step of mixing the dispersion containing the rubber or resin additive and solvent with at least one selected from the group consisting of thermoplastic resins, rubbers and thermoplastic elastomers.

According to the present invention, it is possible to obtain an additive for rubber or resin that can be easily dispersed in rubber or thermoplastic resin and can improve the tensile strength of rubber or thermoplastic resin.

When the content of the organic compound having a hydrophobic group having a high affinity with a hydrophilic group and carbon is small (when the surface of the flaky carbon is coated with an organic compound having a hydrophobic group having a high affinity with a hydrophilic group and carbon) The composition of the additive for rubber or resin of the present invention is shown. The present invention of the present invention when the content of an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon is large (when flaky carbon is dispersed in an organic compound having a hydrophobic group having a high affinity with carbon). The composition of the additive for rubber or resin is shown. The transmission electron microscope image of the cross section of the flaky carbon obtained in Example 2 is shown.

As used herein, "contains" is a concept that includes any of "comprise," "consist essentially of," and "consist of." Further, in the present specification, when the numerical range is indicated by "A to B", it means A or more and B or less.

Hereinafter, embodiments of the present invention will be described, but various modifications of the embodiments and details are possible without departing from the spirit and scope of the claims.

1. 1. Additives for rubber or resin The additive for rubber or resin of the present invention contains flaky carbon having a thickness of 1 to 100 nm and an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon.

(1-1) Flaky carbon As the flaky carbon, the thinner one is preferable because it has excellent strengthening properties such as tensile strength, tensile elongation, and elastic modulus with respect to rubber or resin, but the thickness thereof is 1 to 100 nm, preferably 1 to 20 nm. Is. Similarly, the content ratio of flaky carbon having a thickness of 1 to 10 nm is preferably 80% or more, more preferably 90% or more, assuming that the total number of flaky carbons is 100%. That is, although flaky carbon having a large thickness may be contained, the thickness of a large number of flaky carbons is preferably 10 nm or less. The thickness of the flaky carbon is measured by observation with a transmission electron microscope (TEM).

The thin piece of carbon is preferable because it has excellent strengthening properties such as tensile strength, tensile elongation, and elastic modulus with respect to rubber or resin. However, the thin piece of carbon has a layered structure in which 300 layers or less (that is, 1 to 300 layers) of graphene are laminated. Carbon is preferable, and flaky carbon having a layered structure in which 1 to 60 layers of graphene are laminated is more preferable. Similarly, the content ratio of flaky carbon having 1 to 30 layers is preferably 80% or more, more preferably 90% or more, assuming that the total number of flaky carbons is 100%. That is, although flaky carbon having a large thickness may be contained, the thickness of a large number of flaky carbons is preferably 30 layers or less. The lamination of flaky carbon is calculated from the thickness measured by observation with a transmission electron microscope (TEM).

Since flaky carbon usually has a planar shape having many convex and concave angles, it is difficult to unconditionally specify a size other than the thickness. In the present specification, the distance between the most distant convex angles in one flaky carbon is defined as the size of the flaky carbon.

The size of such flaky carbon is preferably 20 nm or more, more preferably 100 nm or more, and even more preferably 200 nm or more. By using flaky carbon of such a size, it is easy to further improve the strengthening characteristics such as tensile strength, tensile elongation, and elastic modulus with respect to rubber or resin. The size of the flaky carbon is preferably 100 μm because the larger the size is, the better the reinforcing characteristics such as tensile strength, tensile elongation, and elastic modulus with respect to rubber or resin are, and the upper limit of the size is not limited. The size of flaky carbon is measured by observation with a transmission electron microscope (TEM).

The content of flaky carbon in the additive for rubber or resin of the present invention is not particularly limited, but from the viewpoint of strengthening properties such as tensile strength, tensile elongation, and elastic modulus with respect to rubber or resin, the rubber or resin of the present invention. The total amount of the additives for use is 100% by mass, preferably 50 to 99.5% by mass, more preferably 60 to 99.2% by mass.

(1-2) Organic compound having a hydrophilic group and a hydrophobic group having a high affinity with carbon In the present invention, the graphene structure is maintained by using an organic compound having a hydrophilic group and a hydrophobic group having a high affinity with carbon. The flaky carbon in the rubber or resin additive of the present invention can be maintained in a uniformly dispersed state without agglomeration of the flaky carbon. An organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon can also function as a dispersant for uniformly dispersing flaky carbon.

The organic compound having such a hydrophilic group and a hydrophobic group having a high affinity for carbon is not particularly limited, and various organic compounds (particularly water-soluble compounds) that can function as a dispersant for flaky carbon are used. Can be used.

Among them, the hydrophobic group contained in the organic compound having a hydrophilic group and a hydrophobic group having a high affinity with carbon is not particularly limited, but is an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, and a poly having 3 or more carbon atoms. An oxyalkylene group or the like is preferable. An organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon can contain one or more such hydrophobic groups. When a plurality of hydrophobic groups are used, the same hydrophobic group may be used, a plurality of the same hydrophobic group may be used, or a plurality of different hydrophobic groups may be used.

The alkyl group may be a chain alkyl group or a branched chain alkyl group, but a chain alkyl group is preferable from the viewpoint of affinity with carbon. The number of carbon atoms of the alkyl group is preferably 2 or more, more preferably 3 to 22, and even more preferably 4 to 18 from the viewpoint of affinity with carbon. Such alkyl groups include butyl group, pentyl group, hexyl group, octyl group, decyl group, undecyl group, dodecyl group (or lauryl group), tridecyl group, tetradecyl group (or myristyl group), pentadecyl group and hexadecyl group. (Or a cetyl group), an octadecyl group and the like can be mentioned.

This alkyl group may or may not have a substituent. Examples of such a substituent include a cycloalkyl group, an aryl group, an aralkyl group and the like. Examples of the cycloalkyl group and the aryl group will be described later.

As the aralkyl group as the substituent of the alkyl group, an aralkyl group having 7 to 14 carbon atoms having an aryl group and an alkyl group having 1 to 6 carbon atoms, which will be described later, is preferable, and specifically, a benzyl group, a phenethyl group and the like are used. preferable.

The substituent is not limited to the above, and may have a group derived from a fluorene structure (fluorenyl group or the like). In particular, when water solubility is important, a phenyl group or the like is preferable as a substituent, and when compatibility with flaky carbon is important, a naphthyl group, a fluorenyl group or the like is preferable as a substituent.

The alkenyl group preferably has 2 or more carbon atoms, more preferably 3 to 100 carbon atoms, and even more preferably 4 to 30 carbon atoms from the viewpoint of affinity with carbon and water solubility. Examples of such an alkenyl group include a butenyl group, a hexenyl group, an octenyl group, a decenyl group, a dodecenyl group, an oleyl group, a linoleyl group and the like.

This alkenyl group may or may not have a substituent. Examples of such a substituent include an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group and the like. Examples of the aralkyl group include those described above, and examples of the cycloalkyl group and the aryl group include those described below.

As the alkyl group as the substituent of the alkenyl group, an alkyl group having 1 to 6 carbon atoms is preferable, and specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a tert-butyl group and the like are preferable.

The substituent is not limited to the above, and may have a group derived from a fluorene structure (fluorenyl group or the like). In particular, when water solubility is important, a phenyl group or the like is preferable as a substituent, and when compatibility with flaky carbon is important, a naphthyl group, a fluorenyl group or the like is preferable as a substituent.

As the cycloalkyl group, a cycloalkyl group having 5 to 10 carbon atoms (preferably 5 to 8, particularly 5 to 6) is preferable, and specifically, a cyclopentyl group, a cyclohexyl group and the like are preferable.

This cycloalkyl group may or may not have a substituent. Examples of such a substituent include an alkyl group, an aryl group, an aralkyl group and the like.

As the alkyl group as the substituent of the cycloalkyl group, an alkyl group having 1 to 6 carbon atoms is preferable, and specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a tert-butyl group and the like are preferable.

Examples of the aryl group and the aralkyl group as the substituent of the cycloalkyl group include those exemplified above.

The substituent is not limited to the above, and may have a group derived from a fluorene structure (fluorenyl group or the like). In particular, when water solubility is important, a phenyl group or the like is preferable as a substituent, and when compatibility with flaky carbon is important, a naphthyl group, a fluorenyl group or the like is preferable as a substituent.

As the aryl group, an aryl group having 6 to 22 carbon atoms (particularly 6 to 18) is preferable, and any monocyclic aryl group, condensed ring aryl group or polycyclic aryl group can be adopted, for example, a phenyl group, a naphthyl group, etc. Examples thereof include anthrasenyl group, tetrasenyl group, phenanthrenyl group, biphenyl group, terphenyl group, fluorenyl group, acenaphthenyl group, acenaphthylenyl group, pyrenyl group, chrysenyl group, triphenylenyl group and the like. From the viewpoint of affinity with carbon, an aryl group having two or more aromatic rings (condensed aryl group and polycyclic aryl group) is preferable.

This aryl group may or may not have a substituent. Examples of such a substituent include an alkyl group, a cycloalkyl group, an aralkyl group and the like.

As the alkyl group as the substituent of the aryl group, an alkyl group having 1 to 6 carbon atoms is preferable, and specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a tert-butyl group and the like are preferable.

Examples of the cycloalkyl group and the aralkyl group as the substituent of the aryl group include those exemplified above.

The substituent is not limited to the above, and may have a group derived from a fluorene structure (fluorenyl group or the like).

The polyoxyethylene group is usually hydrophilic, but the polyoxyalkylene group having 3 or more carbon atoms, such as a polyoxypropylene group and a polyoxybutylene group, becomes more hydrophobic as the degree of polymerization increases and functions as a hydrophobic group. In particular, a polyoxypropylene group having a degree of polymerization of 4 or more and a polyoxybutylene group having a degree of polymerization of 3 or more are preferable. However, the degree of polymerization is preferably 1000 or less from the viewpoint of strengthening properties such as tensile strength, tensile elongation, and elastic modulus with respect to rubber or resin. For example, when polyoxyethylene-polyoxypropylene or polyoxyethylene-polyoxybutylene is used as an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon, the polyoxypropylene group and the polyoxybutylene group are also used. Can function as a hydrophobic group.

This polyoxyalkylene group having 3 or more carbon atoms may or may not have a substituent. Examples of such a substituent include an alkyl group, a cycloalkyl group, an aralkyl group, an aryl group and the like.

As the alkyl group as a substituent of the polyoxyalkylene group having 3 or more carbon atoms, an alkyl group having 1 to 6 carbon atoms is preferable, and specifically, a methyl group, an ethyl group, a propyl group, a butyl group and a tert-butyl group. Groups and the like are preferred.

Examples of the cycloalkyl group, the aralkyl group and the aryl group as the substituent of the polyoxyalkylene group having 3 or more carbon atoms include those exemplified above.

The substituent is not limited to the above, and may have a group derived from a fluorene structure (fluorenyl group or the like). In particular, when water solubility is important, a phenyl group or the like is preferable as a substituent, and when compatibility with flaky carbon is important, a naphthyl group, a fluorenyl group or the like is preferable as a substituent.

As such a hydrophobic group, an aryl group and a polyoxyalkylene group having 3 or more carbon atoms are preferable from the viewpoints of affinity with carbon, tensile strength to rubber or resin, tensile elongation, elastic modulus and other reinforcing properties. , Aryl groups are more preferred, and aryl groups having two or more aromatic rings (condensed aryl groups and polycyclic aryl groups) are even more preferred. Specifically, a naphthyl group, an anthrasenyl group, a tetrasenyl group, a phenanthrenyl group, a biphenyl group, a terphenyl group, a fluorenyl group, an acenaphthenyl group, an acenaphthylenyl group, a pyrenyl group, a chrysenyl group, a triphenylenyl group, and a polyoxypropylene having a degree of polymerization of 4 or more. A group, a polyoxybutylene group having a degree of polymerization of 3 or more, and the like are preferable.

Further, as the hydrophilic group of the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon, the solubility of the organic compound having a hydrophobic group having a high affinity for the hydrophilic group and carbon in water can be increased. There is no particular limitation as long as it is, but the water solubility of the organic compound having a hydrophobic group having a high affinity with the hydrophilic group and carbon, the dispersibility of flaky carbon, the tensile strength to rubber or resin, the tensile elongation, the elastic coefficient, etc. From the viewpoint of the strengthening characteristics of the above, general formulas (1) to (4):

[In the formula, -OH represents an alcoholic hydroxyl group or a phenolic hydroxyl group. R represents a divalent organic group. X ¹ represents a hydrogen atom, alkali metal, NH ₄ or organic ammonium. X ² represents a hydrogen atom, alkali metal, NH ₄ , organic ammonium or alkyl group. The oxygen atom of the general formula (2) is an ether bond. ]
The hydrophilic group represented by is preferable. The organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon can contain one or more such hydrophilic groups. When a plurality of hydrophilic groups are used, the same hydrophilic group may be used more than once, a plurality of types of hydrophilic groups represented by the same general formula may be used, or hydrophilicity represented by different general formulas may be used. A plurality of types of groups may be used.

In the general formula (1), -OH may be either an alcoholic hydroxyl group or a phenolic hydroxyl group. From the viewpoints of water solubility of organic compounds having hydrophilic groups and hydrophobic groups having a high affinity for carbon, dispersibility of flaky carbon, tensile strength with respect to rubber or resin, tensile elongation, strengthening properties such as elastic coefficient, etc., it is alcoholic. When a hydroxyl group is preferable, but a phenolic hydroxyl group is contained (particularly, when a plurality of phenolic hydroxyl groups are contained), a benzene ring having excellent hydrophobicity is inevitably included, and the tensile strength and tension with respect to rubber or resin as a whole are included. It is preferable because it has excellent strengthening properties such as elongation and elasticity.

In particular, when it has a benzenetriol structure (pyrogallol structure, hydroxyquinol structure, fluoroglusinol structure, etc.), a benzenediol structure (catechol structure, resorcinol structure, hydroquinone structure, etc.) (especially when it has two or more), rubber or It is particularly excellent in strengthening properties such as tensile strength, tensile elongation and elastic modulus with respect to resin, and is particularly effective for strengthening tensile strength, tensile elongation and elastic modulus with respect to rubber such as styrene / butadiene rubber. As the organic compound having a hydrophilic group having such a structure and a hydrophobic group having a high affinity for carbon, not only an artificially synthesized compound but also a naturally occurring polyphenol can be used.

Polyphenol is a general term for compounds also called polyphenols, and means a general term for compounds in which two or more hydrogens of aromatic hydrocarbons are substituted with hydroxyl groups, or a mixture thereof. Such polyphenols are not particularly limited, and are, for example, catechin, epicatechin, gallocatechin, epigallocatechin, catechin gallate, epicatechin gallate, gallocatechin gallate, epigallocatechin gallate, quercetin, hesperidin, tannic acid, teaflavin, etc. Examples thereof include procyanidin, leukoanthocyanidin, and rutin. Among these, viewpoints such as water solubility of organic compounds having hydrophilic groups and hydrophobic groups having high affinity with carbon, dispersibility of flake carbon, tensile strength to rubber or resin, tensile elongation, elastic modulus and other strengthening properties. Therefore, tannic acid, catechin and the like are preferable.

Since these polyphenols are present in many plants, the plants may be used as they are, or plant extracts may be used. On the other hand, polyphenol may be purified by a conventional method and used. In particular, the effects of water solubility of an organic compound having a stable hydrophilic group and a hydrophobic group having a high affinity for carbon, dispersibility of flaky carbon, and strengthening properties such as tensile strength, tensile elongation, and elastic modulus with respect to rubber or resin are effective. Since it can be obtained, it is preferable to use a purified product (purified alcohol product or the like).

In the general formula (2), the divalent organic group represented by R is not particularly limited, and a divalent hydrocarbon group is preferable. Examples of the divalent hydrocarbon group include an aliphatic hydrocarbon group (alkylene group (or alkylidene group), cycloalkylene group, alkylene (or alkylidene) -cycloalkylene group, bi or tricycloalkylene group, etc.), aromatic hydrocarbon. Examples thereof include a group (arylene group, alkylene (or alkylidene) -arylene group, etc.).

In the general formula (2), as the alkylene group (or alkylidene group) represented by the group R, an alkylene group is preferable, a C _1-8 alkylene group is more preferable, a C _1-4 alkylene group is further preferable, and a C _{2- A 4-} alkylene group is particularly preferable, and a C _2-3 alkylene group is most preferable. Specifically, methylene group, ethylene group, ethylidene group, trimethylene group, propylene group, propyridene group, tetramethylene group, ethylethylene group, butane-2-idene group, 1,2-dimethylethylene group, pentamethylene group, Examples thereof include a pentane-2,3-diyl group.

In the general formula (2), as the cycloalkylene group represented by the group R, a C _5-10 cycloalkylene group is preferable, and a C _5-8 cycloalkylene group is more preferable. Specifically, a cyclopentylene group, a cyclohexylene group, a methylcyclohexanelen group, a cycloheptylene group and the like can be exemplified.

In the general formula (2), as the alkylene (or alkylidene) -cycloalkylene group represented by the group R, an alkylene-cycloalkylene group is preferable, a C _1-6 alkylene-C _5-10 cycloalkylene group is more preferable, and C _{A 1-4} alkylene-C _5-8 cycloalkylene group is more preferred. Specifically, methylene-cyclohexylene group, ethylene-cyclohexylene group, ethylene-methylcyclohexylene group, ethylidene-cyclohexylene group and the like can be exemplified.

In the general formula (2), a norbornane-diyl group or the like can be specifically exemplified as the bi or tricycloalkylene group represented by the group R.

In the general formula (2), the C _6-10 arylene group is preferable as the arylene group represented by the group R. Specifically, a phenylene group, a naphthalene diyl group and the like can be exemplified.

In the general formula (2), as the alkylene (or alkylidene) -arylene group represented by the group R, an alkylene-arylene group is preferable, a C _1-6 alkylene-C _6-20 arylene group is more preferable, and C _1-4. An alkylene-C _6-10 arylene group is more preferable, and a C _1-2 alkylene-phenylene group is particularly preferable. Specifically, a methylene-phenylene group, an ethylene-phenylene group, an ethylene-methylphenylene group, an ethylidene phenylene group and the like can be exemplified.

Of these, a divalent aliphatic hydrocarbon group, particularly an alkylene group (for example, a C _1-4 alkylene group such as a methylene group or an ethylene group) is preferable.

The alkylene (or alkylidene) -cycloalkylene group and the alkylene (alkylidene) -arylene group are -Ra-Rb- (in the formula, Ra is an alkylene bonded to a separate oxygen atom in the general formula (2). A group or an alkylidene group, Rb indicates a cycloalkylene group or an arylene group).

The hydrophilic group represented by the general formula (2) is not particularly limited, and for example, -OC ₂ H ₄ O-, -OC ₃ H ₆ O-, -OCH ₂ O- and the like can be used. .. Those having a plurality of these (preferably 3 to 100) can also be preferably used, and for example, a trioxyethylene group, a tetraoxyethylene group, a polyoxymethylene group, a polyoxyethylene group, a polyoxypropylene group and the like are used. can do. In particular, when the hydrophilic group represented by the general formula (2) has a structure in which three or more are polymerized, the more carbons in R (for example, three or more carbon atoms), the lower the hydrophilicity and the more hydrophobic, so the degree of polymerization is high. -OC ₂ H ₄ O- and -OCH ₂ O-, which can maintain hydrophilicity even when increased, are preferable.

When having such a hydrophilic group represented by the general formula (2), particularly a polyoxyalkylene group, and further a polyoxyethylene group, the reinforcing properties such as tensile strength, tensile elongation, and elastic modulus with respect to rubber or resin It is excellent and is particularly effective for strengthening tensile strength, tensile elongation, elastic modulus, etc. with respect to resins such as polypropylene.

In the general formula (3), the alkali metal represented by X ¹ is not particularly limited, and examples thereof include sodium, potassium, lithium and the like.

In the general formula (3), quaternary ammonium is preferable as the organic ammonium represented by X ¹ , and tetramethylammonium, tetraethylammonium, tetrapropylammonium, tetrabutylammonium and the like can be preferably used.

The hydrophilic group represented by the general formula (3) is not particularly limited, but is, for example, −SO ₃ ⁻ H ⁺ , −SO ₃ ⁻ Na ⁺ , −SO ₃ ⁻ K ⁺ , −SO ₃ ⁻ Li. ⁺ , -SO ₃ ^- NH ₄ ⁺ , -SO ₃ ^- N (CH ₃ ) ₄ ⁺ , -SO ₃ ^- N (C ₂ H ₅ ) ₄ ⁺ , -SO ₃ ^- N (C ₃ H ₇ ) ₄ ⁺ , −SO ₃ ⁻ N (C ₄ H ₉ ) ₄ ^{+ and the} like can be mentioned.

In the general formula (4), examples of the alkali metal and organic ammonium represented by X ² include those exemplified above.

In the general formula (4), the alkyl group represented by X ² may be a chain alkyl group or a branched chain alkyl group, but has an affinity for carbon, tensile strength with respect to rubber or resin, tensile elongation, and elastic modulus. A chain alkyl group is preferable from the viewpoint of strengthening properties such as. The number of carbon atoms of the alkyl group is preferably 1 to 2 from the viewpoint of affinity with carbon and strengthening properties such as tensile strength, tensile elongation, and elastic modulus with respect to rubber or resin.

The hydrophilic group represented by the general formula (4) is not particularly limited, but is, for example, -COOH, -COONa, -COOK, -COOLi, -COONH ₄ , -COON (CH ₃ ) ₄ , -COON. (C ₂ H ₅ ) ₄ , -COON (C ₃ H ₇ ) ₄ ⁺ , -COON (C ₄ H ₉ ) ₄ ^{+ and the} like can be mentioned.

Among these hydrophilic groups, the water solubility of organic compounds having a hydrophilic group and a hydrophobic group having a high affinity for carbon, stability regardless of pH, dispersibility of flaky carbon, tensile strength to rubber or resin, tension From the viewpoint of strengthening properties such as elongation and elastic modulus, the hydrophilic group represented by the general formula (1) or (2) is preferable.

However, when the water-soluble compound has a plurality of the same hydrophilic groups represented by the general formula (2), that is, has a polymerized structure, the hydrophilicity of the water-soluble compound increases as the degree of polymerization increases when the number of carbon atoms is 2 or less, but the number of carbon atoms is 3. In the above cases, the hydrophobicity may increase as the degree of polymerization increases.

Further, in the present invention, when a nonionic material (nonionic surfactant or the like) is used as the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon, the HLB value thereof is the hydrophilic group and the HLB value. From the viewpoints of water solubility of an organic compound having a hydrophobic group having a high affinity with carbon, dispersibility of flaky carbon, and strengthening properties such as tensile strength, tensile elongation, and elasticity with respect to rubber or resin, 12 or more is preferable, and 13 ~ 19 is more preferable. When the hydrophobic groups are the same (when the affinity with flaky carbon is about the same), the higher the HLB value is, the more preferable.

The organic compound having a hydrophilic group satisfying the above conditions and a hydrophobic group having a high affinity with carbon is not particularly limited, but an aromatic water-soluble compound may be used, or a non-aromatic water-soluble compound may be used. May be used, but aromatic water-soluble compounds are preferred. Examples of the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon include polyoxyethylene lauryl ether, polyoxyethylene decyl ether, polyoxypropylene decyl ether, polyoxyethylene lauryl ether, and polyoxyethylene naphthyl ether. Polyoxypropylene lauryl ether, polyoxypropylene naphthyl ether, polyoxyethylene myristyl ether, polyoxypropylene myristyl ether, polyoxyethylene cetyl ether, polyoxypropylene cetyl ether, polyoxyethylene octylphenyl ether, polyoxypropylene octylphenyl ether, Polyoxyethylene undecylphenyl ether, polyoxypropylene undecylphenyl ether, polyoxyethylene tridecylphenyl ether, polyoxypropylene tridecylphenyl ether, polyoxyethylene pentadecylphenyl ether, polyoxypropylene pentadecylphenyl ether, polyoxy Ethylene polyoxypropylene glycol, polyoxypropylene polyglyceryl ether, sodium colate, potassium colate, sodium dodecylsulfonate, potassium dodecylsulfonate, sodium dilauroyl glutamate lysine, potassium dilauroyl glutamate lysine, decaglycerin laurate ester, n- Decyl alcohol, catechin (polyphenol derived from green tea, etc.), epicatechin, galocatechin, epigalocatechin, catechin gallate, epicatechin gallate, galocatechin gallate, epigalocatechin gallate, quercetin, hesperidin, tannic acid, theaflavin, procyanidin, leukoanthocyanidin, Rutin and the like can be mentioned.

Examples of the organic compound having such a hydrophilic group and a hydrophobic group having a high affinity for carbon include Emargen 103, Emargen 104P, Emargen 105, Emargen 106, Emargen 108, Emargen 109P, Emargen 120, Emargen 123P, and Emargen 130K. Emalgen 147, Emalgen 150, Emalgen 210P, Emalgen 220 (above, polyoxyethylene alkyl ethers manufactured by Kao Co., Ltd.), Triton X-100, Triton X-114, Triton X-305, Triton X-405 (Dow Chemical Co., Ltd.) Polyoxyethylene octylphenyl ethers manufactured by), Neugen EN, Neugen EN-10 (polyoxyethylene naphthyl ether manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), tannic acid, catechins (epicatechin, epigallocatechin, epicatechin gallate). Epigallocatechin gallate, catechin, galocatechin, catechin gallate, galocatechin gallate, etc., including polyphenols), epigallocatechin gallate, epigallocatechin gallate, persimmon astringent (including tannins), etc. can be used.

The content of the organic compound having a hydrophilic group and a hydrophobic group having a high affinity with carbon in the additive for rubber or resin of the present invention is not particularly limited, but the tensile strength, tensile elongation, elastic modulus, etc. with respect to rubber or resin are not particularly limited. From the viewpoint of reinforcing properties, the total amount of the rubber or resin additive of the present invention is 100% by mass, preferably 0.5 to 50% by mass, and more preferably 0.8 to 40% by mass. The content of the organic compound having a hydrophilic group and a hydrophobic group having a high affinity with carbon in the additive for rubber or resin of the present invention is not particularly limited, but has tensile strength, tensile elongation, and elastic modulus with respect to rubber or resin. From the viewpoint of strengthening characteristics such as, 0.01 to 0.9 parts by mass is preferable, and 0.02 to 0.8 parts by mass is more preferable with respect to 1 part by mass of flaky carbon. When the content of the organic compound having a hydrophilic group and a hydrophobic group having a high affinity with carbon is small, the additive for rubber or resin of the present invention has an affinity with the hydrophilic group and carbon on the surface of the flaky carbon. It has a structure in which an organic compound having a high hydrophobic group is coated (Fig. 1). On the other hand, when the content of the organic compound having a hydrophilic group and a hydrophobic group having a high affinity with carbon is large, the additive for rubber or resin of the present invention is contained in the organic compound having a hydrophobic group having a high affinity with carbon. It has a structure in which flaky carbon is dispersed in (Fig. 2). In either case, an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon intervenes around the flaky carbon to suppress aggregation of the flaky carbon, and has tensile strength and tensile elongation with respect to rubber or resin. , A material having an excellent elastic modulus can be obtained.

(1-3) Other components In the rubber or resin additive of the present invention, other components may be contained in addition to flaky carbon and organic compounds having a hydrophilic group and a hydrophobic group having a high affinity for carbon. Good. Examples of such other components include carbon fibers (particularly carbon nanofibers having a fiber diameter of 500 nm or less), activated carbon, carbon black (acetylene black, oil furnace black, etc .; particularly high conductivity and large specific surface area). Black), glassy carbon, carbon microcoil, fullerene, biomass-based carbon materials (bagas, sorghum, wood chips, shavings, bamboo, bark, rice straw, paddy husks, coffee husks, tea husks, tea husks, rice bran, pulp waste, etc. Raw materials; carbon fibers manufactured from lignin, etc.), cellulose nanofibers, boron nitride, molybdenum compounds (molybdenum disulfide, organic molybdenum, etc.), tungsten disulfide, fluororesins (polytetrafluoroethylene (PTFE), tetrafluoro) Ethylene / perfluoroalkyl vinyl ether copolymer (PFA), etc.), melamine cyanurate, phthalocyanine, lead oxide, calcium fluoride, layered minerals (mica, talc, etc.), etc. are used as long as the effects of the present invention are not impaired. You can also do it.

However, from the viewpoint that it is easy to disperse in rubber or resin, the uniformity and adhesion of the coating film when applied are further improved, and the strengthening properties such as tensile strength, tensile elongation and elastic modulus with respect to rubber or resin are further improved. Therefore, the content of other components is preferably small, preferably 0.01 to 10% by mass, and 0.02 to 5% by mass, where the total amount of the rubber or resin additive of the present invention is 100% by mass. More preferred.

The shape of the rubber or resin additive of the present invention is not particularly limited, and examples thereof include a coating film, a sheet, and a lump.

As described above, such an additive for rubber or resin of the present invention is a material that can be easily dispersed in rubber or thermoplastic resin and can enhance the tensile strength, tensile elongation, elastic modulus, etc. of the resin or rubber. Therefore, in the conventional additive, although the elastic modulus is improved, the tensile strength and the tensile elongation are decreased, which is an advantageous material for strengthening rubber or resin.

Such rubber additives of the present invention include tires, shoe soles, athletic supplies, floor tiles, belts, hoses, impact-resistant containers, anti-vibration rubber, rolls, wire coatings, paints, sealing materials, packings, gaskets, windows. Resin additives such as door frames, weather strips, antistatic sheets, diaphragms, coking materials, handrails, and thermoplastic elastomer additives include various injection molded products, extrusion molded products, sheet molded products, blow molded products, and compression products. It can be used for applications such as molded products.

2. Method for Producing Additive for Rubber or Resin The additive for rubber or resin of the present invention is, for example,
(1) It can be produced by a step of removing a solvent from a dispersion containing the flaky carbon, the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon, and a solvent.

(2-1) Dispersion (flammed carbon dispersion)
In a dispersion containing a flake carbon, an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon, and a solvent (flake carbon dispersion), the flake carbon, the hydrophilic group and carbon The above description can be adopted for an organic compound having a hydrophobic group having a high affinity. Further, the flaky carbon dispersion may contain the above-mentioned other components, if necessary.

This flaky carbon dispersion may be formed as a dispersion liquid or as a coating film on a substrate. At this time, as the solvent used for producing the flaky carbon dispersion (fluffy carbon dispersion liquid or flaky carbon coating film), the dispersibility of the flaky carbon, the obtained rubber or the rubber in the resin additive Alternatively, it is preferable to use water as the main solvent from the viewpoint of strengthening properties such as tensile strength, tensile elongation, and elastic modulus with respect to the resin.

The content of water in the solvent used is not particularly limited, but the dispersibility of flaky carbon, the tensile strength of the obtained rubber or resin additive to the rubber or resin, the tensile elongation, the reinforcing properties such as elastic modulus, etc. From the viewpoint, the total amount of the solvent is 100% by mass, and it is preferably 70% by mass or more (70 to 100% by mass), more preferably 75 to 100% by mass.

In the present invention, only water may be used as the solvent, and an organic solvent may not necessarily be used, but an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon can be added to water. In order to further improve the solubility, alcohols such as methanol, ethanol, 2-propanol and tert-butyl alcohol; glycols such as ethylene glycol; glycerin; and organic solvents such as 2-methoxyethanol may be used.

The content of the organic solvent in the solvent used is the solubility of an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon, the tensile strength, tensile elongation, and elasticity of the obtained rubber or resin additive with respect to the rubber or resin. From the viewpoint of strengthening characteristics such as rate, the total amount of the solvent is 100% by mass, and it is preferably 30% by mass or less (0 to 30% by mass), more preferably 5 to 25% by mass.

In the above-mentioned flaky carbon dispersion, the content of flaky carbon is not particularly limited, but from the viewpoint of easy composition of the rubber or resin additive of the present invention, the total amount of flaky carbon dispersion is set to 100% by mass. It is preferably 20% by mass or less, more preferably 0.0001 to 15% by mass, still more preferably 0.001 to 10% by mass. Similarly, the content of the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon is not particularly limited, but from the viewpoint of easy composition of the additive for rubber or resin of the present invention, flaky carbon dispersion. Assuming that the total amount of the body is 100% by mass, 0.000001 to 30% by mass is preferable, 0.00001 to 15% by mass is more preferable, and 0.001 to 10% by mass is further preferable. Similarly, the content of the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon in the flaky carbon dispersion is not particularly limited, but the composition of the additive for rubber or resin of the present invention can be easily obtained. Therefore, 0.01 to 0.9 parts by mass is preferable, and 0.02 to 0.8 parts by mass is more preferable with respect to 1 part by mass of flaky carbon. Further, the content of the solvent is not particularly limited, but from the viewpoint that the composition of the rubber or resin additive of the present invention can be easily obtained, the total amount of the flaky carbon dispersion is 100% by mass, and 40 to 99.9998% by mass. Preferably, 63 to 99.998% by mass is more preferable, and 85 to 99.98% by mass is further preferable.

(2-2) Method for producing flaky carbon dispersion In the present invention, the method for producing the flaky carbon dispersion is not particularly limited, and has high affinity for flaky carbon, hydrophilic groups and carbon with respect to the solvent. An organic compound having a hydrophobic group can also be added. Specifically, flaky carbon can be added to a dispersion of an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon, or a dispersion of flaky carbon having an affinity for a hydrophilic group and carbon. It is also possible to add an organic compound having a high hydrophobic group. Further, flaky carbon and an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon can be simultaneously added to the solvent.

However, from the viewpoint of further improving the dispersibility of flaky carbon to make it difficult to aggregate, and further enhancing the strengthening properties such as tensile strength, tensile elongation, elastic modulus, etc. of the obtained rubber or resin additive of the present invention with respect to rubber or resin. From the above, a carbonaceous material having a layered structure and an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon between the rotating rotating disk and the disk installed substantially parallel to the rotating disk. It is preferable to apply shear to the carbonaceous material in the composition while installing the composition containing the above and adjusting the shortest distance between the rotating disk and the disk to be 200 μm or less (grinding method). ..

Further, the flaky carbon dispersion is subjected to a pressure treatment of 30 MPa or more on a composition containing a carbonaceous material having a layered structure and an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon. It can also be preferably produced (high pressure dispersion method).

Conventionally, when flaky carbon is produced by a wet method, an aqueous dispersion containing an oxide of flaky carbon and an aqueous solvent has been subjected to a reduction treatment, but it is difficult to maintain the graphene structure by this method. At the same time, it was difficult to obtain a flaky carbon aqueous dispersion because the obtained flaky carbon aggregated violently. There was also a problem from the viewpoint of safety. On the other hand, in the present invention, by using an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon, the flaky carbon maintaining the graphene structure is uniformly dispersed without agglomeration (flaky carbon). The flaky carbon can be obtained from the dispersion), the obtained flaky carbon is not easily destroyed, the flaky carbon can be obtained in a short time, and the lumps that have failed to be peeled off are hard to remain. At this time, the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon can also function as a dispersant for uniformly dispersing flaky carbon.

Further, according to the shearing method, since the direction in which the force is applied is parallel to the plane direction of the carbonaceous material having a layered structure and the processing is performed in a narrow space, it is different from the conventional manufacturing method by high-speed stirring, ultrasonic treatment, etc. In comparison, flaky carbon with less fracture and a larger size (for example, flaky carbon with a size of 1 μm or more) can be obtained, and the peeling efficiency is good and the treatment is performed in a short time (small number of passes). In addition to being able to do so, it is difficult for thick lumps that have failed to peel off to remain.

Carbonaceous material having a layered structure The carbonaceous material having a layered structure is not particularly limited, and examples thereof include natural graphite, artificial graphite, expanded graphite, earthy graphite, and graphite oxide. As the graphite oxide, for example, graphite oxidized by one or more kinds of oxidizing agents such as sulfuric acid, nitric acid, potassium permanganate, and hydrogen peroxide can be used. For example, when graphite oxide is obtained by the Hammers method, the graphite is immersed in concentrated sulfuric acid, potassium permanganate is added to oxidize the graphite, and then the reaction product is quenched with dilute sulfuric acid and / or hydrogen peroxide. After that, by washing with distilled water or the like, oxygen atoms are bonded to carbon atoms, and oxygen atoms are introduced between the layers to obtain graphite oxide.

Among them, in the case of obtaining highly pure flaky carbon containing no heteroatoms such as oxygen, it is preferable to use graphite as a raw material, and natural graphite and expanded graphite are more preferable. When expanded graphite is used, it is preferable to use expanded graphite with less oxidation of the graphene structure. When expanded graphite is used, it may be used after being heat-treated at about 300 to 1000 ° C. for about 10 seconds to 5 hours. This makes it possible to obtain expanded graphite that has been appropriately expanded.

Further, when importance is attached to ease of production, graphite oxide may be used. By using graphite oxide, solvent molecules are easily inserted between the layers, it is easy to exfoliate only in the layer direction, and the thinning efficiency and dispersibility are improved, so that the treatment time can be shortened. is there. However, when graphite oxide is used, a reduction treatment is required later, and from the viewpoint of maintaining the graphene structure, conductivity and strength, other materials (natural graphite, artificial graphite, expanded graphite, earthy graphite) Is preferable.

On the other hand, it is also possible to use earth-like graphite in order to further improve the dispersibility. However, from the viewpoint of crystallinity, purity and structure maintenance, other materials (natural graphite, artificial graphite, expanded graphite, graphite oxide) are preferable.

Further, when the crystallinity, strength, structure maintenance and the like of the obtained flaky carbon are emphasized, artificial graphite can also be used.

In the present invention, the content of the carbonaceous material having a layered structure in the composition containing the carbonic material having a layered structure and the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon is not particularly limited. The total amount of the composition used for producing the flaky carbon dispersion is 100% by mass, preferably 20% by mass or less, more preferably 0.0001 to 15% by mass, further preferably 0.001 to 10% by mass. preferable. As for the content of the carbonaceous material having a layered structure, the thinner the material, the more likely it is that flaking (delamination) occurs, so that flaky carbon can be obtained more efficiently, and the number of treatments tends to be reduced. There is a tendency that it is easy to perform shearing treatment while maintaining the viscosity appropriately. On the other hand, the higher the content of the carbonaceous material having a layered structure, the more excellent the productivity. Therefore, from the viewpoint of balancing the efficiency of flaking, viscosity, productivity, etc., it is preferable to appropriately set the content of the carbonaceous material having a layered structure. When a carbonaceous material dispersion is used, it is preferable that the content of the carbonaceous material having a layered structure in the flaky carbon dispersion is within the above range.

Organic compound having a hydrophobic group having a high affinity with a hydrophilic group and carbon As the organic compound having a hydrophobic group having a high affinity with a hydrophilic group and carbon, the above-mentioned ones can be adopted.

In the present invention, the content of the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon in the composition used for producing the flaky carbon dispersion is not particularly limited, but the flaky carbon dispersion is not particularly limited. With the total amount of the composition used for producing the above as 100% by mass, 0.000001 to 30% by mass is preferable, 0.0001 to 15% by mass is more preferable, and 0.001 to 10% by mass is further preferable. On the other hand, in the present invention, the content of the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon in the composition used for producing the flaky carbon dispersion is a carbonaceous material 1 having a layered structure. 0.01 to 0.9 parts by mass is preferable, and 0.02 to 0.8 parts by mass is more preferable with respect to parts by mass. As for the content of the organic compound having a hydrophilic group and a hydrophobic group having a high affinity with carbon, the thinner the content, the larger the content of the carbonaceous material having a relatively layered structure, and the tensile strength and tensile elongation with respect to rubber or resin. Reinforcement characteristics such as elastic modulus are easily improved, and processing is easy at low cost. On the other hand, the higher the content of the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon, the more likely it is that flaking (delamination) occurs, so flaky carbon tends to be obtained more efficiently. As the viscosity increases, the flaking efficiency may decrease. Therefore, from the viewpoint of balancing tensile strength, tensile elongation, elastic modulus, cost, efficiency of flaking, etc., it is preferable to appropriately set the content of the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon. .. When a carbonaceous material dispersion is used in this production method, the content of the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon in the carbonaceous material dispersion is within the above range. Is preferable.

Solvent In the above-mentioned method for producing a flaky carbon dispersion, as described above, a composition containing a carbonaceous material having a layered structure and an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon is used. Although it is preferable to carry out a specific treatment, carbon having a layered structure is obtained from the viewpoints of fragmentation efficiency of the carbonaceous material having a layered structure, tensile strength, tensile elongation, elastic coefficient, etc. of the obtained additive for rubber or resin. It is preferable to carry out a specific treatment on the carbonaceous material dispersion containing the quality material and the organic compound having a hydrophilic group and a hydrophobic group having a high affinity with carbon.

The carbonaceous material dispersion may be formed as a dispersion liquid or as a coating film on a substrate.

At this time, the above-mentioned solvent can be adopted as the solvent used for producing the carbonaceous material dispersion (carbonaceous material dispersion liquid or carbonaceous material coating film).

In the present invention, when a specific treatment is carried out using a carbonaceous material dispersion using a solvent, the total amount of the solvent in the carbonaceous material dispersion is not particularly limited, but the carbonic material having a layered structure is fragmented. From the viewpoint of efficiency, solubility of an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon, etc., the total amount of the carbonaceous material dispersion is 100% by mass, preferably 40 to 99.9998% by mass, and 63 to 99%. .998% by mass is more preferable, and 85 to 99.98% by mass is further preferable.

In the present invention, when a specific treatment is carried out using a carbonaceous material dispersion using a solvent, the carbonaceous material dispersion has a layered structure on an organic compound dispersion having a hydrophilic group and a hydrophobic group having a high affinity for carbon. A carbonaceous material having a layered structure may be charged, or an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon may be charged into the carbonaceous material dispersion having a layered structure. Further, a carbonaceous material having a layered structure and an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon may be simultaneously added to the solvent.

Other Ingredients In the present invention, the composition containing a carbonaceous material having a layered structure and an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon (for example, a carbonaceous material dispersion) may be used. Ingredients may be included. As a result, these other components can be contained in the finally obtained flaky carbon dispersion and the additive for rubber or resin. As such other components, those described above can be adopted and may be used as long as the effects of the present invention are not impaired. However, from the viewpoint that it is easy to disperse in the resin and it is easy to obtain an additive for rubber or resin that further improves the uniformity, adhesion, tensile strength, tensile elongation, elastic modulus, etc. of the coating film at the time of application, other methods are used. The content of the component is preferably small, and the total amount of the carbonaceous material dispersion is 100% by mass, preferably 0.00001 to 5% by mass, and more preferably 0.0001 to 2% by mass.

Shearing (grinding method)
In the present invention, when the grinding method is adopted, as described above, a carbonaceous material having a layered structure, a hydrophilic group and carbon are provided between the rotating rotating disk and the disk installed substantially parallel to the rotating disk. A composition containing an organic compound having a hydrophobic group having a high affinity with the above is installed, and the carbonaceous material in the composition is adjusted so that the shortest distance between the rotating disk and the disk is 200 μm or less. On the other hand, it is preferable to perform a process of applying shear. When a carbonaceous material dispersion is used, the carbonaceous material dispersion is installed between the rotating rotating disk and the disk installed substantially parallel to the rotating disk, and the rotating disk and the above-mentioned rotating disk are installed. It is preferable to perform a treatment of applying shear to the carbonaceous material in the carbonaceous material dispersion while adjusting the shortest distance from the board to 200 μm or less.

The graphene structure may not be maintained depending on the conditions because the carbonaceous material having a layered structure is atomized by the shearing treatment, but the carbonaceous material having a layered structure is efficiently sliced. It is possible to reduce the processing time. The rotating disk and the disk when performing such a shearing process are installed substantially in parallel, but they do not have to be strictly parallel. Specifically, the angle formed by the axis perpendicular to the rotating disk and the axis perpendicular to the disk is preferably 10 ° or less, and more preferably 5 ° or less. It is most preferable that the axis perpendicular to the rotating disk and the axis perpendicular to the disk are strictly parallel. The shortest distance between the two surfaces when performing such a shearing treatment is not particularly limited as long as the carbonaceous material having a layered structure can be sufficiently thinned, but is preferably 200 μm or less. ~ 50 μm is more preferable, and 2 to 30 μm is even more preferable. Although the rotating disk and the disk are installed substantially in parallel, the distance between the rotating disk and the disk may differ depending on the location. In this case, the shortest distance between the rotary disc and the disc means the distance of the shortest portion of the distance between the rotary disc and the disc. Further, it is not always necessary to leave the rotary disk and the disk apart in advance, a material to be processed may be sandwiched between the rotary disk and the disk, and the rotary disk and the disk may be brought into contact with each other. By sandwiching the carbonaceous material having a layered structure, the space between the rotating disk and the disk may be widened. Such a shearing process may be performed by using a stone mill, a vibrating mixer, a spin coater, a grinder, or the like, as long as there is a mechanism for rotating a disk-shaped object.

The sizes of the rotating disk and the disk that can be used at this time are not particularly limited, and are preferably 5 to 500 mm, more preferably 10 to 200 mm. The number of rotations of the turntable during the shearing treatment is not particularly limited, and is preferably in the range where the carbonaceous material having a layered structure can be sufficiently thinned, for example, 1000 to 10000 ppm. , 2000-5000 ppm is more preferable.

By performing such a shearing treatment, the plate and the carbonic material having a layered structure, and the carbonic material having a layered structure and the carbonic material having a layered structure are brought into contact with each other to form a layered material with respect to the carbonic material having a layered structure. Shear can be applied in the direction parallel to the graphene layer of the carbonaceous material having a structure.

By reducing the shortest distance between the rotating disk and the rotating disk in the shearing process and increasing the rotational speed of the rotating disk, the conditions can be strengthened, and a thin piece of carbonaceous material having a layered structure can be obtained. The conversion can be performed more efficiently, and the processing time can be further reduced. This shearing operation can be performed once or more, preferably three or more times.

The temperature at which the shearing treatment is performed is not particularly limited, and may be a temperature at which the carbonaceous material having a layered structure can be sufficiently thinned, and is 0 ° C. or higher, further 0 to 100 ° C., particularly 20 to 95 ° C. obtain. The temperature at which the shearing treatment is performed is preferably a condition in which the solubility of the organic compound having a hydrophilic group and a hydrophobic group having a high affinity with carbon is high, and when the higher the temperature, the higher the solubility, the higher the temperature is, and the cloud point is formed. When a water-soluble compound is used, it is preferable to keep the temperature below the cloud point.

Before performing the above shearing treatment, a stirrer, an ultrasonic disperser, or the like is used in order to bring the carbonaceous material having a layered structure into good contact with the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon. The organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon may be blended on the surface of the carbonaceous material having a layered structure by stirring in advance before preparing the composition.

In the present invention, when graphite oxide is used as the carbonaceous material having a layered structure, it exists as an oxide of flaky carbon in the dispersion subjected to the shearing treatment. Therefore, when graphite oxide is used as the carbonaceous material having a layered structure, it is preferable to perform a reduction treatment as a post-treatment. As the reduction treatment, various methods such as chemical reduction and electrochemical reduction can be adopted, but chemical reduction is preferable. Of these, chemical reduction with a reducing agent such as hydrazine or sodium borohydride is preferable. The amount of the reducing agent is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, and even more preferably 0.5 to 3 parts by mass with respect to 1 part by mass of the oxide of flaky carbon. Further, if heating is performed at the time of reduction, the reduction becomes easier. The heating temperature is preferably 40 to 200 ° C, more preferably 50 to 150 ° C, and even more preferably 60 to 120 ° C. The reduction time is preferably 10 minutes to 64 hours, more preferably 30 minutes to 48 hours, still more preferably 1 to 24 hours. However, it is preferable that the graphene structure is not excessively destroyed.

According to the above-mentioned production method, the flaky carbon can be obtained as the above-mentioned flaky carbon dispersion. Since this production method contains an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon, even in a flaky carbon dispersion, the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon can be contained. include. Since this organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon can be adsorbed on the surface of flaky carbon and isolated and dispersed the flaky carbon in a solvent at a high concentration, the flaky carbon is dispersed. It also functions as a dispersant in the body. Further, as the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon, a commercially available product can be used, which is superior to the conventional product in terms of both cost and dispersibility. Further, the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon can exhibit sufficient tensile strength, tensile elongation, elastic modulus, etc. by remaining on the flaky carbon surface.

Further, in the conventional method of performing the oxidation treatment and the reduction treatment, the plastic substrate is hydrolyzed during the reduction treatment, and the flaky carbon aggregates when the reduction treatment is performed, so that it cannot exist as a dispersion. Therefore, it was impossible to form a flaky carbon dispersion on a plastic substrate, but in the present invention, a specific organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon is contained. By performing the treatment, it is also possible to form a flaky carbon dispersion on the substrate without the plastic substrate such as polyethylene terephthalate (PET) being hydrolyzed.

Pressurization treatment (high pressure dispersion method)
In the present invention, when the high-pressure dispersion method is adopted, as described above, 30 MPa is applied to a composition containing a carbonaceous material having a layered structure and an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon. It is preferable to perform the above pressurization treatment.

The graphene structure may not be maintained depending on the conditions because the carbonaceous material having a layered structure is atomized by the pressure treatment, but the carbonaceous material having a layered structure can be efficiently sliced. This can be done and the processing time can be reduced. The pressure level at the time of performing such a pressure treatment is not particularly limited as long as it can sufficiently thin the carbonaceous material having a layered structure, but is preferably 30 MPa or more, preferably 50 to 400 MPa. Is more preferable, and 100 to 300 MPa is further preferable. Such pressurization treatment can be performed using a high-pressure disperser, a supercritical water preparation device, or the like. The high-pressure disperser can disperse by applying mechanical pressure, and in the supercritical water preparation device, the pressure of the system can be increased by heating water.

By such pressurization, for example,
(I) Colliding two or more of the carbonaceous material dispersions with each other.
(Ii) Collision of the carbonaceous material dispersion with a metal or ceramic material (material having high hardness such as silicon carbide or alumina).
(Iii) The carbonaceous material dispersion can be passed through a space having a cross-sectional area of 1 cm ² or less.

According to the above (i) and (ii), the pressurizing condition can be strengthened, the carbonaceous material having a layered structure can be sliced more efficiently, and the processing time can be further reduced. be able to. Further, according to the above (iii), it is possible to more appropriately thin the carbonaceous material having a layered structure while maintaining the graphene structure more appropriately. This pressurizing operation can be performed once or more, preferably 10 times or more.

The pressurizing temperature is not particularly limited and may be a temperature at which the carbonaceous material having a layered structure can be sufficiently thinned. In the cases of (i) and (ii) above, 0 to 100 ° C., particularly 20 It can be ~ 95 ° C. Further, in the case of (iii) above, 0 to 100 ° C. is preferable when mechanically applying pressure, 373 to 700 ° C. is preferable when pressure is generated by the supercritical state of water, and 380 to 450 ° C. is more preferable. preferable.

When the pressure treatment is performed, it is preferable to perform an ultrasonic dispersion treatment as a preliminary treatment (pretreatment) to atomize the carbonaceous material having a layered structure. This can have an effect of preventing clogging and the like.

The output when the ultrasonic dispersion treatment is applied is not particularly limited, but it is stronger than the usual ultrasonic dispersion treatment (about 40 to 50 W) from the viewpoint of thinning the carbonaceous material having a layered structure. Is preferable. Specifically, the output of the ultrasonic dispersion treatment is preferably 100 W or more, more preferably 300 to 20000 W, and even more preferably 400 to 18000 W.

The ultrasonic dispersion temperature is not particularly limited, and may be a temperature at which the carbonaceous material having a layered structure can be sufficiently thinned, and may be 0 to 80 ° C., particularly 10 to 70 ° C. The ultrasonic dispersion time is not particularly limited, and may be a time during which the carbonaceous material having a layered structure can be sufficiently thinned, and may be 1 to 600 minutes, particularly 3 to 120 minutes.

Further, as the pretreatment or the posttreatment of these treatments, a dispersion treatment by another dispersion device such as ordinary mechanical stirring, a dispersion treatment by an emulsifying device, and a dispersion treatment by a bead mill may be used in combination.

In the present invention, when graphite oxide is used as the carbonaceous material having a layered structure, it exists as an oxide of flaky carbon in the dispersion subjected to the pressure treatment. Therefore, when graphite oxide is used as the carbonaceous material having a layered structure, it is preferable to perform a reduction treatment as a post-treatment. As the reduction treatment, various methods such as chemical reduction and electrochemical reduction can be adopted, but chemical reduction is preferable. Of these, chemical reduction with a reducing agent such as hydrazine or sodium borohydride is preferable. The amount of the reducing agent is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, and even more preferably 0.5 to 3 parts by mass with respect to 1 part by mass of the oxide of flaky carbon. Further, if heating is performed at the time of reduction, the reduction becomes easier. The heating temperature is preferably 40 to 200 ° C, more preferably 50 to 150 ° C, and even more preferably 60 to 120 ° C. The reduction time is preferably 10 minutes to 64 hours, more preferably 30 minutes to 48 hours, still more preferably 1 to 24 hours. However, it is preferable that the graphene structure is not excessively destroyed.

(2-3) Method for Producing Additive for Rubber or Resin of the Present Invention The additive for rubber or resin of the present invention can be obtained by removing the solvent from the above-mentioned flaky carbon dispersion.

In order to remove the solvent, a method of concentrating the flaky carbon dispersion can be mentioned. In addition to drying the flaky carbon dispersion, a method of spin-coating the flaky carbon dispersion on a substrate or drying after coating, usually It can be carried out by the method of recovering the heat conductive material of the present invention by solid-liquid separation of the above. As a method for performing solid-liquid separation, for example, a method used for ordinary solid-liquid separation, for example, a method of filtering using a filter paper, a glass filter, or the like; a method of filtering after centrifugation; a vacuum filter is used. The method can be exemplified. Next, the drying method is not particularly limited, and for example, a method of drying at about 50 to 200 ° C. for about 1 to 24 hours using a warm air dryer or the like can be exemplified.

3. 3. Flake carbon material The rubber or resin additive of the present invention has a flake carbon surface covered with an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon, or has a high affinity for the hydrophilic group and carbon. Even if it has a structure in which flaky carbon is dispersed in an organic compound having a hydrophobic group, it has sufficient tensile strength, tensile elongation, elastic coefficient, etc., but if necessary, the said It is possible to remove an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon. Specifically, the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon can be removed by heat treatment at 400 to 600 ° C., preferably 450 to 550 ° C. to obtain the flaky carbon material of the present invention. it can.

It is considered that the conventional dispersant is adsorbed by utilizing the hydrophobic interaction between the dispersant molecule and the flaky carbon, and since the molecular weight is relatively large, the adsorbing power is also considered to be large. On the other hand, the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon used in the present invention does not chemically bond with flaky carbon and has a small molecular weight, so that the adsorptive power is weaker than that of the conventional product. Therefore, the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon used in the present invention has an advantage that it is easier to remove from the rubber or resin additive of the present invention than the conventional product.

In this way, a flaky carbon material can be obtained, and the flaky carbon obtained at this time is obtained after the organic compound having a hydrophilic group as a dispersant and a hydrophobic group having a high affinity with carbon has been removed. Even if there is, aggregation can be suppressed, and its tensile strength, tensile elongation, elastic modulus, etc. can be sufficiently exhibited. In this respect, it is a characteristic obtained only through the above-mentioned flaky carbon dispersion and the additive for rubber or resin of the present invention, and aggregation is unavoidable with commercially available flaky carbon or the like.

4. Rubber or Resin Reinforced Composition The rubber or resin reinforced composition of the present invention comprises the above-mentioned rubber or resin additive of the present invention or the flaky carbon material of the present invention, and a thermoplastic resin, rubber and thermoplastic elastomer. Contains at least one selected from.

The rubber or resin additive and flaky carbon material of the present invention suppress the aggregation of flaky carbon and are easily dispersed in other materials (for example, rubber, resin, etc.), and therefore are mixed with other materials. By doing so, it can be applied to nanocomposites containing flaky carbon and the like.

As such other materials, more specifically, as the thermoplastic resin, for example, a polyethylene resin, a polypropylene resin, a polystyrene resin, a polyvinyl chloride resin, a polyvinylidene chloride resin, a polyvinyl acetate resin, and a thermoplastic polyurethane resin. , Polyfluorinated vinylidene resin, acrylonitrile-butadiene-styrene copolymer (ABS) resin, acrylonitrile-styrene copolymer (AS) resin, polymethylmethacrylate resin, polyamide resin, polyacetal resin, polycarbonate resin, polyarylate resin, polyphenylene ether Examples thereof include resins, polyethylene terephthalate resins, polybutylene terephthalates, cyclic polyolefin resins, polyphenylene sulfide resins, polyether ether ketone resins, thermoplastic polyimide resins, polyamideimide resins, and examples of the rubber include diene rubbers (styrene / butadiene rubbers). , Isoprene rubber, butadiene rubber, chloroprene rubber, etc.), Olefin rubber (ethylene / propylene rubber, ethylene / propylene / diene rubber, etc.), acrylic rubber, butyl rubber, epichlorohydrin rubber, silicone rubber (silicone rubber, etc.), many Examples thereof include rubber sulfide and fluororubber. Examples of the thermoplastic elastomer include a thermoplastic elastomer having a polyethylene structure, a thermoplastic elastomer having a polypropylene structure, and a thermoplastic elastomer having a butadiene structure (styrene / butadiene / styrene copolymer, etc.). , Thermoplastic elastomer having a polyethylene terephthalate structure, a thermoplastic elastomer having a polyamide 6 structure, a thermoplastic elastomer having a polyamide 66 structure, a thermoplastic elastomer having a polyamide 11 structure, a thermoplastic elastomer having a polyamide 12 structure, and the like. These can be used alone or in combination of two or more. In addition, known or commercially available products can be used as these other materials.

These thermoplastic resins, rubbers and thermoplastic elastomers of the present invention are produced by interacting with hydrophobic groups (for example, π-electron interaction) of organic compounds having a hydrophilic group and a hydrophobic group having a high affinity for carbon. From the viewpoint of further improving the compatibility with the rubber or resin additive, the aromatic polymer compound is preferable. Specifically, styrene-butadiene rubber, styrene-butadiene-styrene copolymer and the like are preferable. Further, from the viewpoint of affinity with carbon materials, polyamide-based thermoplastic resins and thermoplastic elastomers are also preferable.

In the rubber or resin reinforced composition of the present invention, the content of the above-mentioned other materials is not particularly limited, and from the viewpoints of tensile strength, tensile elongation, elastic modulus, etc., the rubber or resin additive of the present invention or flakes It is preferably 0.05 to 99 parts by mass, and more preferably 0.1 to 97 parts by mass with respect to 1 part by mass of the carbon material.

Hereinafter, the present invention will be specifically described with reference to Examples. However, the present invention is not limited to the examples.

Example 1: Flake carbon + polyoxyethylene naphthyl ether + polypropylene 500 g of artificial graphite (manufactured by Showa Denko KK), 250 g of polyoxyethylene naphthyl ether (HLB value 18) and 10000 g of water are mixed, and 600 W ultrasonic waves are used. The dispersion treatment was applied for 5 minutes using a disperser, and the dispersion treatment (colliding two or more carbonaceous material dispersions with each other) was performed 100 times at 245 MPa using a high-pressure disperser.

The obtained dispersion was spray-dried at 220 ° C. to obtain a powder having a diameter of about 50 μm.

When this powder was analyzed by a scanning electron microscope (SEM), a transmission electron microscope (TEM), and Raman spectroscopy, flaky carbon was obtained. The flaky carbon had an average of 4 layers and an average thickness of 1.5 nm.

Further, after mixing 15 g of this powder (of which 10 g is flaky carbon) and 185 g of polypropylene (BC6C manufactured by Japan Polypropylene Corporation; hereinafter sometimes referred to as "PP"), a twin-screw extruder (Co., Ltd.) ) KZW15TW-30MG-NH manufactured by Technobel, diameter 15 mm, L / D = 30) was kneaded at 210 ° C. to obtain 150 g of pellets.

Comparative Example 1: Polypropylene only Polypropylene (BC6C manufactured by Japan Polypropylene Corporation) 200 g, using a twin-screw extruder (KZW15TW-30MG-NH manufactured by Technobel Co., Ltd., diameter 15 mm, L / D = 30) at 210 ° C. Kneading was performed to obtain 170 g of pellets.

Comparative Example 2: Graphite + polypropylene After mixing 10 g of scaly graphite (manufactured by Ito Graphite Industry Co., Ltd.) and 190 g of polypropylene (manufactured by Nippon Polypropylene Corporation BC6C), a twin-screw extruder (KZW15TW-manufactured by Technobel Co., Ltd.) Kneading was carried out at 210 ° C. using 30 MG-NH, diameter 15 mm, L / D = 30) to obtain 160 g of pellets.

Comparative Example 3: Carbon Nanofiber + Polypropylene After mixing 10 g of carbon nanofiber (manufactured by Showa Denko KK) and 190 g of polypropylene (manufactured by Nippon Polypropylene Corporation BC6C), a twin-screw extruder (KZW15TW manufactured by Technobel Co., Ltd.) Kneading was carried out at 210 ° C. using −30 MG-NH, diameter 15 mm, L / D = 30) to obtain 150 g of pellets.

Comparative Example 4: Graphite + Polypropylene After mixing 10 g of artificial graphite (manufactured by Showa Denko Corporation) and 190 g of polypropylene (BC6C manufactured by Japan Polypropylene Corporation) used in Example 1, a twin-screw extruder (manufactured by Nippon Polypro Co., Ltd.) KZW15TW-30MG-NH manufactured by Technobel, diameter 15 mm, L / D = 30) was kneaded at 210 ° C. to obtain 170 g of pellets.

Comparative Example 5: After mixing 10 g of graphite + polypropylene spheroidal graphite (manufactured by Nippon Graphite Industry Co., Ltd.) and 190 g of polypropylene (BC6C manufactured by Japan Polypropylene Corporation), a twin-screw extruder (KZW15TW-30MG manufactured by Technobel Co., Ltd.) Kneading was carried out at 210 ° C. using −NH, diameter 15 mm, L / D = 30) to obtain 170 g of pellets.

Comparative Example 6: After mixing 10 g of graphene (manufactured by Graphene Technology Co., Ltd.) manufactured from commercially available graphene + polypropylene CO ₂ and 190 g of polypropylene (BC6C manufactured by Japan Polypropylene Corporation), a twin-screw extruder (Co., Ltd.) ) KZW15TW-30MG-NH manufactured by Technobel, diameter 15 mm, L / D = 30) was kneaded at 210 ° C. to obtain 170 g of pellets.

Test Example 1: Tensile test (1)
The pellets obtained in Example 1 and Comparative Examples 1 to 6 were dried at 80 ° C. for 24 hours, and then lengthened at 230 ° C. using an injection molding machine (C, MOBILE-0813 manufactured by Shinko Selvik Co., Ltd.). It was formed into a dumbbell-shaped test piece having a size of 75 mm × width of parallel portion 5 mm × length of parallel portion 35 mm × thickness 2 mm, and a tensile test was conducted in accordance with JIS K7161-1: 2014. The results are shown in Table 1.

In Comparative Examples 2 to 6, the tensile elastic modulus was improved, but the tensile strength and the tensile elongation were decreased as compared with Comparative Example 1 (PP alone). That is, it is considered that the material becomes hard but brittle. It is presumed that this is because the carbon component and PP have a poor affinity and breakage from the interface occurs.

On the other hand, in Example 1, the tensile elastic modulus, the tensile strength, and the tensile elongation were all improved as compared with Comparative Example 1, and the toughness was maintained without impairing the flexibility. It can be presumed that this is because the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon was kneaded in a state of being adsorbed on the surface, so that flaky carbon was dispersed in the PP and the affinity of the interface was improved.

Example 2: Flake carbon + polyoxyethylene naphthyl ether + styrene-butadiene-styrene copolymer 500 g of natural graphite (manufactured by Ito Graphite Industry Co., Ltd.), polyoxyethylene naphthyl ether (HLB value 18) 125 g and water 10000 g Was mixed and stirred to obtain a mixed solution.

This mixed solution was subjected to one shearing treatment at 1500 rpm for 30 minutes using a ceramic grinder having a radius of 300 mm. The shortest distance of the ceramic grinder was about 10 μm.

The obtained dispersion was dried under reduced pressure at 90 ° C. to obtain a black flake-like solid. The cross section of the obtained flaky carbon was observed with a transmission electron microscope. The results are shown in FIG.

10 g of this solid and 190 g of a styrene-butadiene-styrene copolymer (thermoplastic elastomer; Toughprene A manufactured by Asahi Kasei Chemicals Co., Ltd.) are mixed, and a twin-screw extruder (KZW15TW-30MG-NH manufactured by Technobel Co., Ltd.), diameter 15 mm. , L / D = 30) was kneaded at 200 ° C. to obtain 150 g of pellets.

Example 3: Flake carbon + polyoxyethylene naphthyl ether + styrene-butadiene-styrene copolymer 500 g of natural graphite (manufactured by Ito Graphite Industry Co., Ltd.), polyoxyethylene naphthyl ether (HLB value 13) 125 g and water 10000 g Was mixed and stirred to obtain a mixed solution. Using this mixed solution, the following operations were carried out in the same manner as in Example 2 to obtain 150 g of pellets of Example 3.

Example 4: Flake carbon + polyoxyethylene naphthyl ether + styrene-butadiene-styrene copolymer 500 g of natural graphite (manufactured by Ito Graphite Industry Co., Ltd.), polyoxyethylene naphthyl ether (HLB value 13) 250 g and water 10000 g Was mixed and stirred to obtain a mixed solution.

This mixed solution was subjected to one shearing treatment at 1500 rpm for 30 minutes using a ceramic grinder having a radius of 300 mm. The shortest distance of the ceramic grinder was about 10 μm.

The obtained dispersion was dried under reduced pressure at 90 ° C. to obtain a black flake-like solid.

12 g of this solid and 188 g of a styrene-butadiene-styrene copolymer (thermoplastic elastomer; Toughprene A manufactured by Asahi Kasei Chemicals Co., Ltd.) were mixed, and a twin-screw extruder (KZW15TW-30MG-NH manufactured by Technobel Co., Ltd.), diameter 15 mm , L / D = 30) was kneaded at 200 ° C. to obtain 150 g of pellets.

Example 5: Flaky carbon + tannic acid + styrene-butadiene-styrene copolymer 500 g of natural graphite (manufactured by Ito Graphite Industry Co., Ltd.), tannic acid (manufactured by Kishida Chemical Co., Ltd.) 250 g and 10000 g of water are mixed. The mixture was stirred to obtain a mixed solution. Using this mixed solution, the following operations were carried out in the same manner as in Example 4 to obtain 150 g of pellets of Example 5.

Example 6: Flake carbon + green tea-derived polyphenol + styrene-butadiene-styrene copolymer 500 g of natural graphite (manufactured by Ito Graphite Industry Co., Ltd.), green tea-derived polyphenol (manufactured by Pharma Foods Co., Ltd.) 250 g and 10000 g of water. A mixed solution was obtained by mixing and stirring. Using this mixed solution, the following operations were carried out in the same manner as in Example 4 to obtain 150 g of pellets of Example 6.

Comparative Example 7: Styrene-butadiene-styrene copolymer only 200 g of styrene-butadiene-styrene copolymer (thermoplastic elastomer; Toughprene A manufactured by Asahi Kasei Chemicals Co., Ltd.), twin-screw extruder (KZW15TW manufactured by Technobel Co., Ltd.) Kneading was carried out at 200 ° C. using −30 MG-NH, diameter 15 mm, L / D = 30) to obtain 170 g of pellets.

Test Example 2: Tensile test (Part 2)
The pellets obtained in Examples 2 to 6 and Comparative Example 7 were dried at 80 ° C. for 24 hours, and then lengthened at 210 ° C. using an injection molding machine (C, MOBILE-0813 manufactured by Shinko Selvik Co., Ltd.). It was formed into a dumbbell-shaped test piece having a size of 75 mm × width of parallel portion 5 mm × length of parallel portion 35 mm × thickness 2 mm, and a tensile test was conducted in accordance with JIS K7161-1: 2014. The results are shown in Table 2.

In Examples 2 to 6, although the carbon component was added in a large amount of 4% by mass, the tensile strength was improved as compared with Comparative Example 7. Further, in Examples 2 to 6, the elastic modulus was also improved as compared with Comparative Example 7. This is an unexpected result because the tensile strength usually decreases when the additive is added. Further, although the tensile strength of Example 4 in which the amount of the same organic compound is increased is relatively lower than that of Example 3, the strength of Examples 5 and 6 is the same as that of Example 4. Was expensive. The organic compounds used in Examples 5 and 6 are polyphenols and have three or more benzene rings, which are larger than those of the organic compounds used in Examples 2-4. It is considered that the strength was improved by the π-electron interaction between the benzene ring and the benzene ring having the styrene structure of the elastomer.

As described above, conventionally, when the carbon material is composited with rubber or resin, the elastic modulus is improved, but the flexibility is lowered, so that the tensile elongation is lowered, and as a result, the tensile strength is also tended to be lowered. In the present invention, the elastic modulus and tensile elongation of rubber or resin are simultaneously improved by coexisting an organic compound having a hydrophilic group and a hydrophobic group having a high affinity with carbon with flaky carbon and dispersing them in rubber or resin. As a result, the tensile strength could be improved.

Claims (12)

An additive for rubber or resin, which contains flaky carbon having a thickness of 1 to 100 nm and an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon. The rubber or resin according to claim 1, wherein 1 part by mass of the flaky carbon contains 0.01 to 0.9 parts by mass of an organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon. Additive. The hydrophilic group is a general formula (1) to (4):
[In the formula, -OH represents an alcoholic hydroxyl group or a phenolic hydroxyl group. R represents a divalent organic group. X ¹ represents a hydrogen atom, alkali metal, NH ₄ or organic ammonium. X ² represents a hydrogen atom, alkali metal, NH ₄ , organic ammonium or alkyl group. The oxygen atom of the general formula (2) is an ether bond. ]
The rubber or resin additive according to claim 1 or 2, which is at least one kind represented by. The additive for rubber or resin according to any one of claims 1 to 3, wherein the hydrophilic group is a phenolic hydroxyl group and / or a polyoxyethylene group. Any one of claims 1 to 4, wherein the hydrophobic group is at least one selected from the group consisting of an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, and a polyoxyalkylene group having 3 or more carbon atoms. The additive for rubber or resin described in 1. The additive for rubber or resin according to any one of claims 1 to 5, wherein the hydrophobic group is an aryl group having two or more aromatic rings. The method for producing an additive for rubber or resin according to any one of claims 1 to 6.
(1) A production method comprising a step of removing a solvent from a dispersion containing the flaky carbon, the organic compound having a hydrophilic group and a hydrophobic group having a high affinity for carbon, and a solvent. The production method according to claim 7, wherein the step of removing the solvent is a step of concentrating the dispersion. The production method according to claim 7 or 8, wherein the solvent is water. A rubber or resin reinforced composition containing the heat conductive material according to any one of claims 1 to 6 and at least one selected from the group consisting of a thermoplastic resin, a rubber and a thermoplastic elastomer. The rubber or resin reinforced composition according to claim 10, wherein the thermoplastic resin, rubber and thermoplastic elastomer are aromatic polymer compounds. The method for producing a rubber or resin reinforced composition according to claim 10 or 11.
(2) A production method comprising a step of mixing the dispersion containing the rubber or resin additive and solvent with at least one selected from the group consisting of thermoplastic resins, rubbers and thermoplastic elastomers.