JP2015199812A - conductive carbon material-containing composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conductive carbon material-containing composition comprising a polysiloxane compound suitable as a dispersant for a conductive carbon material such as carbon nanotube.SOLUTION: A conductive carbon material-containing composition comprises a polysiloxane compound having a nonionic substituent in a side chain and a conductive carbon material.

Description

The present invention relates to a conductive carbon material-containing composition. More specifically, the present invention relates to a conductive carbon material-containing composition that can be suitably used as a raw material for conductive thin films and the like.

A polysiloxane compound is a compound having a Si—O bond (siloxane bond), and has been widely used as a raw material for various industrial products. And nowadays, it has been applied to various uses due to characteristics such as heat resistance caused by siloxane bonds. As an example of a composition using such a polysiloxane compound, an organic skeleton having an imide bond is bonded to a silicon atom forming a siloxane bond as a curable resin composition capable of giving a cured product having excellent heat resistance. A resin composition containing a silane compound having a structural unit and an organic resin is disclosed (for example, see Patent Document 1).

Incidentally, carbon nanotubes (hereinafter also referred to as CNT) are cylindrical compounds composed only of carbon having excellent electrical conductivity and mechanical strength, and are expected to be used in various applications. However, CNTs are difficult to disperse due to strong cohesion due to high van der Waals interactions, and their application to functional materials is limited.
As one of the utilization forms of such CNTs, a conductive thin film using CNTs has been studied. A conductive thin film using CNTs is produced by applying an ink composition in which CNTs are dispersed in a solvent by various printing methods and coating methods. At this time, hydrophilic polymers and various surfactants are used as CNT dispersants, but problems such as changing the electrical properties of the thin film due to deterioration due to air contact when these surfactants are exposed to heat. was there.
On the other hand, as an attempt to increase the heat resistance of the CNT dispersant, CNT dispersion using a polysiloxane compound has been studied (for example, see Non-Patent Document 1).

Japanese Patent No. 5193217

T ARAKE and five others "Polymer", (Netherlands) 2013, Vol. 54, p5643-5647 Y Kaneko and five others "Chemistry of Materials" (USA) 2004, Vol. 16, p3417-3423

The composition using the polysiloxane compound as described above as a dispersant for CNT is a new use of the polysiloxane compound. However, in the composition described in Non-Patent Document 1, the dispersibility of CNT in a solvent can be improved. In terms of this point, there is still room for developing a conductive carbon material-containing composition containing a polysiloxane compound suitable as a dispersant for conductive carbon materials such as carbon nanotubes.

This invention is made | formed in view of the said present condition, and it aims at providing the conductive carbon material containing composition containing a polysiloxane compound suitable as a dispersing agent of conductive carbon materials, such as a carbon nanotube.

As a result of various studies on the polysiloxane compound, the present inventors have prepared a composition using a polysiloxane compound having a nonionic substituent in the side chain as a dispersant for the conductive carbon material. The present inventors have found that the dispersibility in the water is improved and have reached the present invention.

That is, this invention is a conductive carbon material containing composition containing the polysiloxane compound which has a nonionic substituent in a side chain, and a conductive carbon material.
The present invention is described in detail below.
A combination of two or more preferred embodiments of the present invention described below is also a preferred embodiment of the present invention.

The conductive carbon material-containing composition of the present invention includes a polysiloxane compound having a nonionic substituent in the side chain (hereinafter also referred to as a polysiloxane compound having a nonionic substituent) and a conductive carbon material. Although it is included, as long as these are included, other components may be included. In addition, the conductive carbon material-containing composition of the present invention may contain one or more polysiloxane compounds having a nonionic substituent in the side chain and two or more kinds of conductive carbon materials. Good.

The said nonionic substituent is a substituent which does not have the group (ionic group) which generates ion.
A conductive carbon material-containing composition using a polysiloxane compound having a nonionic substituent in the side chain is excellent in dispersibility of the conductive carbon material in a solvent. In addition, as described in Non-Patent Document 1 described above, polysiloxane compounds have been studied as dispersants for conductive carbon materials such as carbon nanotubes, but polysiloxane compounds in Non-Patent Document 1 are ionic. And also contains ionic impurities. When a composition containing a compound having an ionic side chain and an ionic impurity is used as a dispersant for the conductive carbon material, the dispersibility is not sufficient. This is considered to be due to the low affinity between the conductive carbon material and the composition containing an ionic side chain compound and ionic impurities. In addition, when a conductive thin film is manufactured using carbon nanotubes dispersed with such a polysiloxane compound, there is a risk that leakage or short-circuiting due to ionic impurities may occur and reliability may be impaired. On the other hand, when a polysiloxane compound having a nonionic substituent in the side chain is used as a dispersant, excellent dispersibility is exhibited. This is probably because the polysiloxane compound having a nonionic substituent has higher affinity with the conductive carbon material than the composition containing a compound having an ionic side chain and an ionic impurity. . Moreover, since the conductive carbon material containing composition of this invention becomes a thing with low ionicity, it can suppress the leak and short circuit by an ionic impurity of the thin film produced from a composition.

The nonionic substituent is not particularly limited as long as it does not have an ionic group. However, the aromatic ring group of the aromatic compound, the heterocyclic group of the heterocyclic compound, the alicyclic group of the alicyclic compound, and the carbon number of 1 Examples include a substituent having an acyclic aliphatic hydrocarbon group such as an alkyl group, an alkenyl group, and an alkynyl group of ˜20, a hydroxyl group, a halogen atom, and an OR ¹ group. R ¹ is the same or different and represents at least one group selected from the group consisting of an alkyl group, an acyl group, an aryl group and an unsaturated aliphatic residue, and a substituent such as an alkyl group, a halogen atom and an aromatic group There may be.
Note that hydrogen atoms are not included in the nonionic substituent.

Examples of the aromatic compound include benzene, biphenylene, terphenylene, naphthalene, anthracene, and perylene. Examples of the heterocyclic compound include pyrrolidine, pyrrole, piperidine, imidazole, pyrazole, thiazole, imidazoline, indole, purine, quinoline and the like. Examples of the saturated aliphatic cyclic hydrocarbon of the alicyclic compound include cyclobutane, cyclopentane, cyclohexane, cyclooctane, norbornane, decahydronaphthalene and the like, and the unsaturated aliphatic cyclic hydrocarbon of the alicyclic compound. Examples thereof include cyclobutene, cyclopentene, cyclohexene, cyclooctene, and norbornene.

The nonionic substituent is preferably a substituent having at least one group selected from the group consisting of an aromatic ring group, a heterocyclic group and an alicyclic group, more preferably a substituent having an aromatic ring group. It is. When the polysiloxane compound having a nonionic substituent has a substituent having an aromatic ring group, it is a structure in which a π electron cloud of an aromatic ring and an aromatic ring are continuously formed, and has a π-conjugated structure. It is considered that the dispersibility of the conductive carbon material can be further improved by exhibiting a high affinity due to the superconjugated interaction with the conductive carbon material. The nonionic substituent is more preferably a substituent having at least one aromatic ring group selected from the group consisting of benzene, biphenylene, terphenylene, naphthalene, anthracene, and perylene.

The nonionic substituent is preferably a substituent having an imide bond. The polysiloxane compound having a substituent having an imide bond in the side chain has high heat resistance and is excellent in dispersibility of the conductive carbon material in a solvent. For this reason, when a polysiloxane compound having a substituent having an imide bond is used, a conductive carbon material-containing composition having high heat resistance and excellent dispersibility of the conductive carbon material can be obtained.
The nonionic substituent having an imide bond is not particularly limited as long as it contains an imide bond site in the structure and does not contain an ionic group. The imide bond site is represented by the following formula (1):

(Wherein R ² and R ³ are the same or different and represent a hydrogen atom or a monovalent or divalent organic group. R ² and R ³ may combine to form a ring structure. .) Is preferable.
When the organic group is a monovalent organic group, the monovalent organic group is preferably a hydrocarbon group having 1 to 10 carbon atoms.
When the organic group is a divalent organic group, that is, when R ² and R ³ are bonded to form a ring structure with the —C—N—C— site, the structure of the imide bond site is Is preferably a maleimide structure or an imide bond site structure in the formula (2) described later.

As the nonionic substituent having the imide bond, the imide bond site is an aromatic compound ring structure (aromatic ring), a heterocyclic compound ring structure (heterocycle), and an alicyclic compound ring structure (alicyclic ring). And at least one structure selected from the group consisting of:
The nonionic substituent having an imide bond includes (1) a structure having an alkylene group having 1 to 6 carbon atoms, (2) a structure having a secondary amino group, and (3) a structure having a tertiary amino group. Those having an imide bond site at the end of any of the structures are preferred. Among these, (1) a structure having an imide bond site at the terminal of an alkylene group having 1 to 6 carbon atoms is more preferable in that it becomes a polysiloxane compound having high thermal stability.

The nonionic substituent having an imide bond is not particularly limited as long as it is an organic group containing an imide bond, but is preferably a group represented by the following formula (2).

(In the formula, R ⁴ represents at least one structure selected from the group consisting of aromatic, heterocyclic and alicyclic rings. X and z are the same or different and are integers of 0 or more and 5 or less, y is 0 or 1.)
At least one structure selected from the group consisting of aromatic, heterocyclic and alicyclic rings is a group in which R ⁴ has an aromatic ring structure (aromatic ring), or a heterocyclic compound ring structure (heterocycle). And at least one group selected from the group consisting of a group having a ring structure and an alicyclic compound ring structure (alicyclic ring).
Examples of the aromatic compound, heterocyclic compound, and alicyclic compound include the aforementioned compounds.
When the composition of this invention contains the compound which has group represented by the said Formula (2), the dispersibility of an electroconductive carbon material can be improved more. This is a group in which the group represented by the above formula (2) has an imide ring, and since the imide ring generally has a π-conjugated structure electronically, the imide ring and the conductive carbon material are superconjugated to each other. This is considered to be due to the high affinity due to action.

R ⁴ is preferably a phenylene group, naphthylidene group, norbornene divalent group, (alkyl) cyclohexylene group, cyclohexenyl group or the like. When R ⁴ is a phenylene group, the nonionic substituent having the imide bond is a group represented by the following formula (2-1), and when R ⁴ is an (alkyl) cyclohexylene group, When the nonionic substituent having an imide bond is a polysiloxane compound represented by the following formula (2-2) and R ⁴ is a naphthylidene group, the nonionic substituent having the imide bond is represented by the following formula (2 -3) or a polysiloxane compound represented by (2-4), and when R ⁴ is a norbornene divalent group, the nonionic substituent having the imide bond is represented by the following formula (2-5). When R ⁴ is a cyclohexenyl group, the nonionic substituent having the imide bond is a polysiloxane compound represented by the following formula (2-6).

In the above formula (2), x and z are the same or different and are integers of 0 or more and 5 or less.
X + z may be an integer of 0 or more and 10 or less, preferably 3 to 7, more preferably 3 to 5, and particularly preferably 3. The y is 0 or 1, and is preferably 0.

In the above formulas (2-1) to (2-6), x, y and z are the same as x, y and z in the above formula (2), respectively.
In the above formula (2-1), R ^{5 to} R ⁸ are the same or different and represent at least one structure selected from the group consisting of a hydrogen atom, an alkyl group, a halogen atom and an aromatic. As said R < ⁵ > -R < ⁸ >, the form whose all are hydrogen atoms is preferable.
In the formula (2-2), R ^{9 to} R ¹² and R ^{9 ′ to} R ^{12 ′} are the same or different and are at least one selected from the group consisting of a hydrogen atom, an alkyl group, a halogen atom and an aromatic. Represents the structure. As the ^R 9 ^{to R 12} and ^{R 9'to R 12 ',} form all ^{R 10} or ^{R 11} are the remaining methyl group is a hydrogen atom, ^or, R 9 ^{to R 12} and ^{R 9'to R 12 'all} are hydrogen atom form ^or embodiment R 9 ^{to R 12} and ^{R 9'to R 12'} all are a fluorine atom is preferable. More preferably, R ¹⁰ or R ¹¹ is a methyl group and the rest are all hydrogen atoms.

In the above formula (2-3), R ^{13 to} R ¹⁸ are the same or different and represent at least one structure selected from the group consisting of a hydrogen atom, an alkyl group, a halogen atom and an aromatic. As said R < ¹³ > -R < ¹⁸ >, the form in which all are hydrogen atoms, or the form in which all are fluorine atoms is preferable. More preferred is a form in which all are hydrogen atoms.
In the above formula (2-4), R ^{19 to} R ²⁴ are the same or different and each represents at least one structure selected from the group consisting of a hydrogen atom, an alkyl group, a halogen atom and an aromatic. As said R < ¹⁹ > -R < ²⁴ >, the form in which all are hydrogen atoms, or the form in which all are fluorine atoms is preferable. More preferred is a form in which all are hydrogen atoms.
In the above formula (2-5), R ^{25 to} R ³⁰ are the same or different and represent at least one structure selected from the group consisting of a hydrogen atom, an alkyl group, a halogen atom and an aromatic. As said R < ²⁵ > -R < ³⁰ >, the form in which all are hydrogen atoms, the form in which all are fluorine atoms, or the form in which all are chlorine atoms is preferable. More preferred is a form in which all are hydrogen atoms.
In the above formula (2-6), R ^{31 to} R ³⁴ , R ^{31 ′} and R ^{34 ′} are the same or different and are at least one selected from the group consisting of a hydrogen atom, an alkyl group, a halogen atom and an aromatic. Represents the structure. As the ^R 31 ^{to R 34, R 31 'and R 34',} it forms all are hydrogen atom, and all are a fluorine atom form or any form of embodiment all is a chlorine atom is preferable. More preferred is a form in which all are hydrogen atoms.

Among the structural units represented by the above formula (2), the following formula (2-7):

(Wherein R ³⁵ represents a structural unit represented by at least one structure selected from the group consisting of aromatic, heterocyclic and alicyclic rings). That is, the polysiloxane compound having a nonionic substituent of the present invention includes a polysiloxane compound in which the nonionic substituent having an imide bond is a substituent represented by the above formula (2-7). Is preferred. R ³⁵ in the above formula (2-7) is preferably the same as R ⁴ described in the above formula (2).

As a particularly preferable form of the polysiloxane compound having a nonionic substituent, poly (γ-phthaloimidopropylsilsesquioxane) in which R ³⁵ is a phenylene group; poly {γ that R ³⁵ is in a methylcyclohexylene group; - propyl silsesquioxane} (Kisahidoro -4-methyl phthalimide ^to); poly {.gamma. (1,8-naphthalimide) propyl silsesquioxane} ^{R 35} is naphthylidene ^{group; R 35} is a naphthylidene group Poly {γ- (2,3-naphthalimide) propylsilsesquioxane}; poly {γ- (5-norbornene-2,3-imido) propylsilsesquioxane} in which R ³⁵ is a divalent group of norbornene Poly [(cis-4-cyclohexene-1,2-imido) propylsyl wherein R ³⁵ is a cyclohexenyl group; Sesquioxane]. More preferably, poly (γ-phthalimidopropylsilsesquioxane), poly {γ- (1,8-naphthalimide) propylsilsesquioxane}, poly {γ- (2,3-naphthalimide) propylsilsesquioxane. Oxan}. The structures of these compounds can be identified by measuring ¹ H-NMR, ¹³ C-NMR, and MALDI-TOF-MS.

The polysiloxane compound having a nonionic substituent only needs to have at least one nonionic substituent in the side chain. In the polysiloxane compound having a nonionic substituent, the nonionic substituent The proportion of the substituent is preferably 50 to 100 mol% with respect to 100 mol% of all side chains in the polysiloxane compound. More preferably, it is 70-100 mol%, More preferably, it is 80-100 mol%, Most preferably, it is 100 mol%. If the proportion of the nonionic substituent is substantially 100 mol%, the conductive carbon material-containing composition of the present invention does not substantially contain ionic impurities, so that the ions of the thin film produced from the composition Leakage and short circuit due to ionic impurities can be more sufficiently suppressed.

When the polysiloxane compound having a nonionic substituent has a nonionic substituent having an imide bond, the proportion of the nonionic substituent having an imide bond is not particularly limited. It is preferable that it is 50-100 mol with respect to 100 mol of all the side chains. More preferably, it is 70-100 mol, More preferably, it is 80-100 mol, Most preferably, it is 100 mol. According to this, the heat resistance of the conductive carbon material-containing composition can be further improved.

The polysiloxane compound having a nonionic substituent has a substituent having at least one group selected from the group consisting of an aromatic ring group, a heterocyclic group, and an alicyclic group as the nonionic substituent. The proportion of these groups is preferably 80 to 100 mol with respect to 100 mol of all side chains in the polysiloxane compound. More preferably, it is 90-100 mol, Most preferably, it is 100 mol.

As the nonionic substituent, a substituent having an imide bond and having at least one group selected from the group consisting of an aromatic ring group, a heterocyclic group, and an alicyclic group is preferable. As a ratio which such a group accounts, it is preferable that it is 50-100 mol with respect to 100 mol of all the side chains in a polysiloxane compound. More preferably, it is 80-100 mol, More preferably, it is 90-100 mol, Most preferably, it is 100 mol.

The polysiloxane compound of the present invention may have an ionic substituent in addition to the nonionic substituent.
Examples of ionic substituents include carboxyl groups or carboxyl group salts, amino groups, amine salts, mercapto groups, sulfonic acid groups or sulfonic acid group salts, phenolic hydroxyl groups or phenolic hydroxyl group salts, phosphonic acid groups or phosphones. Examples thereof include aromatic residues such as alkyl groups having 1 to 20 carbon atoms, such as salts of acid groups, aryl groups, aralkyl groups, unsaturated aliphatic residues, and the like.
It is preferable that the ratio of the ionic substituent which a polysiloxane compound has is 5-50 mol with respect to 100 mol of all the side chains in a polysiloxane compound. More preferably, it is 5-40 mol, More preferably, it is 5-30 mol, Most preferably, it is 5-15 mol.

The polysiloxane compound having the above nonionic substituent has the following average composition formula:
XaYbHcSiOd
(Wherein X is the same or different and represents a nonionic substituent. Y is the same or different and represents a substituent having an ionic group. A is a non-zero number of 3 or less. , B is a number less than 0 or 3, c is a number less than 0 or 3, d is a non-zero number less than 2, and a + b + c + 2d = 4, ie, the coefficient a of X is , 0 <a ≦ 3, the coefficient b of Y is a number 0 ≦ b <3, and the coefficient c of H (hydrogen atom) is a number less than 0 ≦ c <3. The coefficient d can be expressed as 0 <d <2.

In the polysiloxane compound having a nonionic substituent, the dispersibility of the conductive carbon material in the conductive carbon material-containing composition can be improved by increasing the ratio of the nonionic substituent to the silicon atom. it can.
It is preferable that the coefficient a of X in the average composition formula satisfies 0.5 ≦ a ≦ 1.5. If a is in the above range, the dispersibility of the conductive carbon material can be more fully exhibited. More preferably, 0.6 ≦ a ≦ 1.5, still more preferably 0.7 ≦ a ≦ 1.5, particularly preferably 1.0 ≦ a ≦ 1.5, most preferably a = 1.
In the above average composition formula, a + b + c is preferably 0.5 or more, more preferably 0.7 or more, still more preferably 0.7 or more and 1.0 or less, and particularly preferably 1. Further, d which is a coefficient of oxygen is preferably 1.5.

The polysiloxane compound having a nonionic substituent has a nonionic substituent in the side chain. “Having a nonionic substituent in the side chain” means a structure in which the nonionic substituent is bonded to a silicon atom forming the main chain skeleton (siloxane skeleton) of the polysiloxane compound.

The polysiloxane compound having a nonionic substituent is, for example,

(Wherein X and Y are the same or different and are the same as described above. N ₁ and n ₂ indicate the degree of polymerization, n ₁ is a non-zero positive integer, and n ₂ is 0 or M ₁ and m ₂ represent the number of oxygen atoms, and are the same or different and are positive integers. Y / H- represents that Y or H is bonded, X ₁ to ₂ − represents that 1 or 2 X are bonded, and (H / Y) ₁ to ₂ −. Represents that one H or Y is bonded, two H or Y are bonded, or one H and one Y are bonded in total. Si- (X / Y / H) ₃ indicates that any three selected from X, Y and H are bonded to a silicon atom. In the above formula, Si-Om ₁ and Si-Om ₂ is not intended to define the binding order of Si-Om ₁ and Si-Om _2, for example, Si-Om ₁ and Si-Om ₂ is alternately or randomly A co-condensed form, a form in which a polysiloxane composed of Si—Om ₁ and a polysiloxane of Si—Om ₂ are bonded are suitable, and the condensed structure is arbitrary.

The polysiloxane compound having a nonionic substituent can be represented by the above average composition formula: XaYbHcSiOd, and the siloxane skeleton of the polysiloxane compound (main chain skeleton in which siloxane bond is essential) is (SiOm) It can also be expressed as n. The structures other than (SiOm) n are a nonionic substituent X, a substituent Y having an ionic group, and a hydrogen atom, which are bonded to a silicon atom of the main chain skeleton. In the above (SiOm) n, n represents the degree of polymerization, and the degree of polymerization represents the degree of polymerization of the main chain skeleton, and n nonionic substituents may not necessarily exist. In other words, one nonionic substituent does not necessarily exist in one unit of (SiOm) n. In addition, one or more nonionic substituents may be included in one molecule. However, when a plurality of nonionic substituents are included, as described above, two or more nonionic substituents are bonded to one silicon atom. It may be.

In the main chain skeleton (SiOm) n, m is preferably a number of 1.0 or more and less than 2.0. More preferably, m = 1.5 to 1.8. Particularly preferably, m = 1.5. In the main chain skeletons (SiOm ₁ ) n ₁ and (SiOm ₂ ) n ₂ , the range of (n ₁ +1) / (n ₁ + n ₂ +1) is a preferable range of a in the average composition formula: XaYbHcSiOd. The same is preferable. Further, the number of Si atoms bonded to (X / Y / H) ₃ in the above formula and the number of X bonded to Si atoms in (SiOm ₁ ) is preferably one.
N represents the degree of polymerization and is preferably 5 to 200. More preferably, it is 5-100, Most preferably, it is n = 6-100. When the degree of polymerization is within the above preferred range, the film formability of a thin film produced from the conductive carbon material-containing composition can be improved.

It is preferable that the amount of silanol groups calculated | required by the following formula ((alpha)) is 0.1 or less as for the polysiloxane compound which has the said nonionic substituent.
[Si—OH bond moles] / [Si—O bond moles] (α)
According to this, the composition containing the polysiloxane compound having a nonionic substituent can be remarkably reduced in viscosity, and the composition can be extremely excellent in moisture absorption resistance. More preferably, it is 0.05 or less as a silanol group amount calculated | required by the said Formula ((alpha)), More preferably, it is 0.01 or less. Particularly preferably, the polysiloxane compound does not have a residual silanol group. Here, [Si—OH bond mole number] represents the bond number between Si and OH in moles. For example, when two OH groups are bonded to each 1 mol of Si atoms, the [number of moles of Si—OH bond] is 2 mol. The number of moles of Si—O bonds is counted similarly.

The molecular structure of the polysiloxane compound having a nonionic substituent is not particularly limited, and examples thereof include chain (linear, branched), network, ring, cage, cubic, ladder, and the like. Preferred are a chain (linear or branched), a net, a ring, a cage, or a cubic. That is, it is one of the preferable embodiments of the present invention that the polysiloxane compound has at least one polysiloxane skeleton structure selected from the group consisting of chain, network, ring, cage, and cubic.
Here, the molecular structure of the network, basket, or ladder is, for example, the following structural formula:

(Wherein R represents an organic skeleton represented by “XaYbHc” in the above average composition formula).
The structural formula (a) is a random (network structure), the structural formula (b) is an incomplete cage structure, and the structural formulas (c) to (e) are cage structures ( (Complementary condensed structures) and the structural formula (f) indicate a ladder structure.
As exemplified by the structural formulas (b) to (e), the polysiloxane compound having the cage molecular structure preferably has a form in which the organic skeleton layer is a shell portion and the inorganic skeleton layer is a core portion. .

In the polysiloxane compound having a nonionic substituent, the proportion of the siloxane skeleton is preferably 10 to 80% by mass in 100% by mass of the polysiloxane compound. More preferably, it is 15-70 mass%, More preferably, it is 20-50 mass%.

The number average molecular weight and weight average molecular weight of the polysiloxane compound having a nonionic substituent are not particularly limited, but the number average molecular weight is preferably 500 or more, more preferably 700 or more, and still more preferably 1,000. That's it. If the number average molecular weight of the polysiloxane compound having a nonionic substituent is within the above-mentioned preferable range, when a film-like thin film is formed from the conductive carbon material-containing composition, the cracks and the surface when the coating film is dried are roughened. This can be prevented and the film-forming property can be improved. This is considered to be due to the improvement of the film strength of the thin film due to the entanglement between molecules. The number average molecular weight is preferably 100,000 or less.
Moreover, it is preferable that a weight average molecular weight is 1,000 or more, More preferably, it is 1,200 or more. The weight average molecular weight is preferably 200,000 or less.
The molecular weight (number average molecular weight and weight average molecular weight) of the polysiloxane compound having a nonionic substituent can be determined by GPC (gel permeation chromatography) measurement under the measurement conditions described later.

The method for producing the polysiloxane compound having a nonionic substituent is not particularly limited, but a production method including (i) a step of forming a siloxane skeleton and (ii) a step of forming a nonionic substituent is preferable. . Any of the steps (i) and (ii) may be performed first.

(I) The step of forming a siloxane skeleton is not particularly limited, but is preferably a step of forming a siloxane skeleton by hydrolysis / polycondensation reaction of a silane compound having an alkoxysilyl group. For details of the hydrolysis / polycondensation reaction, the method described in Japanese Patent No. 5193217 can be referred to.
(Ii) In the step of forming the nonionic substituent, the method for forming the nonionic substituent is not particularly limited, and a preferable method varies depending on the type of the nonionic substituent, but is performed by a commonly used method. be able to.
When the nonionic substituent is a substituent having an imide bond, a method for producing a polysiloxane compound having a substituent having an imide bond includes (1) adding an acid anhydride to a silane compound having an amino group And (2) imidation step of haloalkyl group of silane compound having halogen atom, (3) production method including any step of imidation of silane compound having isocyanate group is preferable. For the details of the manufacturing method, reference can be made to the method described in Japanese Patent No. 5193217.

The conductive carbon material contained in the conductive carbon material-containing composition of the present invention is not particularly limited as long as it is a carbon material having conductivity. Examples thereof include carbon nanotubes, carbon nanohorns, carbon nanobuds, and graphene. Carbon nanotubes are preferable.

The carbon nanotube has a structure in which a graphene sheet (six-membered ring network made of carbon) is rolled into a cylindrical shape. The carbon nanotube is not particularly limited, and even a single wall carbon nanotube (hereinafter also referred to as SWCNT) made of a single graphene sheet is referred to as a multiwall carbon nanotube (hereinafter also referred to as MWCNT) made of a multilayer graphene sheet. MWCNT is preferred.

Although the diameter of the said carbon nanotube is not specifically limited, It is preferable that it is 1-20 nm, More preferably, it is 2-15 nm.

Although the length of the said carbon nanotube is not specifically limited, It is preferable that it is 0.1-800 micrometers, More preferably, it is 0.5-500 micrometers.

It is preferable that content of the polysiloxane compound which has a nonionic substituent in the said conductive carbon material containing composition is 10-10,000 mass% with respect to 100 mass% of conductive carbon materials, 10-5 It is more preferably 1,000,000% by mass, still more preferably 10-1,000% by mass, and particularly preferably 20-500% by mass. If content of the polysiloxane compound which has a nonionic substituent is the said preferable range, the effect outstanding as a dispersing agent of an electroconductive carbon material can be exhibited.

The conductive carbon material-containing composition may contain other components in addition to the polysiloxane compound having a nonionic substituent and the conductive carbon material, and the other components are not particularly limited, For example, a solvent etc. are mentioned.
The solvent is preferably a nonpolar solvent such as N-methylpyrrolidone, dimethyl sulfoxide, N, N′-dimethylformamide, and more preferably N-methylpyrrolidone.

Content of the said other component shall be 10-1000 mass% with respect to a total of 100 mass% of the mass of the polysiloxane compound which has a nonionic substituent in an electroconductive carbon material containing composition, and an electroconductive carbon material. Is more preferable, and 20 to 500% by mass is more preferable. If content of another component is the said preferable range, the effect outstanding as a dispersing agent of an electroconductive carbon material can be exhibited.

The conductive carbon material-containing composition of the present invention has the above-described configuration and is excellent in dispersibility in a solvent and film formability of a thin film, and therefore can be suitably used for dispersant applications and the like.

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples. Unless otherwise specified, “part” means “part by weight” and “%” means “mass%”.

<GPC measurement conditions>
Measuring instrument: “HLC-8220GPC” manufactured by Tosoh Corporation
Column: “TSK-GEL SUPER HZM-N 6.0 * 150” x 4 manufactured by Tosoh Corporation Eluent: 1 mol% lithium bromide N, N′-dimethylformamide solution Flow rate: 0.6 mL / min Temperature: 40 ° C.
Calibration curve: Prepared using polystyrene standard sample (manufactured by Tosoh Corporation).

<TG-DTA measurement conditions>
Measuring instrument: TG-DTA2000SA (manufactured by Bruker AXS)
Measurement conditions: room temperature to 500 ° C., temperature rising rate 10 ° C./min, nitrogen gas flow (flow rate: 100 mL / min)

<Synthesis Example 1>
Synthesis of poly (3-phthalimidopropyl) silsesquioxane (Compound A) Into a 500 mL four-necked flask equipped with a stirrer, a temperature sensor, and a condenser tube, 86.6 g of diglyme previously dried with molecular sieve and 3-aminopropyl 179.4 g of trimethoxysilane was added, and the temperature was raised to 100 ° C. under a flow of dry nitrogen while stirring to remove moisture in the system. Next, 148.2 g of phthalic anhydride was added in four portions over 30 minutes while maintaining the reaction solution temperature at 80 ° C. It was confirmed by high performance liquid chromatography that phthalic anhydride was completely consumed in 3 hours after the completion of the addition.
Subsequently, 54.2 g of deionized water was added all at once, and the temperature was raised so that by-product methanol was refluxed in the cooling pipe. After holding for 6 hours, the cooling pipe was replaced with a partial condenser, and the temperature was raised again. The reaction liquid temperature was allowed to reach 120 ° C. over 3 hours while collecting raw methanol and condensed water. When the temperature reached 120 ° C., 7.9 g of pyridine was added and the temperature was raised as it was. The temperature reached 160 ° C. over 3 hours while collecting condensed water, and the temperature was maintained at the same temperature for 2 hours and cooled to room temperature.
The reaction product was a dark brown high-viscosity liquid with a non-volatile content of 80.6%. The molecular weight measured by GPC was a number average molecular weight of 2310 and a weight average molecular weight of 2830. ¹ H-NMR and ¹³ C-NMR were measured, and it was confirmed that the compound A represented by the following chemical formula (3) was contained.

<Synthesis Example 2>
Synthesis of poly {γ- (1,8-naphthalimide) propylsilsesquioxane} (Compound B) In a 300 mL four-necked flask equipped with a stirrer, temperature sensor, and condenser, N, N previously dried with molecular sieve 89.3 g of '-dimethylacetamide and 29.7 g of 3-aminopropyltrimethoxysilane were added, and the temperature was raised to 100 ° C. under a flow of dry nitrogen with stirring to remove moisture in the system. Next, 32.8 g of 1,8-naphthalenedicarboxylic acid anhydride was added in 4 portions over 30 minutes while maintaining the temperature of the reaction solution at 100 ° C. It was confirmed by high performance liquid chromatography that 1,8-naphthylic anhydride was completely consumed in 9 hours after the completion of the addition. Subsequently, 9.0 g of deionized water diluted with 6.2 g of N, N′-dimethylacetamide was added all at once, and the temperature was raised so that by-product methanol was refluxed in the cooling tube, and the temperature was maintained at 95 ° C. for 10 hours. After that, the cooling pipe was replaced with a partial condenser, and the temperature was raised again, and the temperature of the reaction solution reached 120 ° C. over 3 hours while collecting by-product methanol and condensed water. When the temperature reached 120 ° C., 2.6 g of pyridine was added and the temperature was raised as it was. The temperature reached 160 ° C. over 3 hours while collecting condensed water, and the temperature was maintained at the same temperature for 3 hours and cooled to room temperature.
The reaction product was a dark brown high-viscosity liquid with a non-volatile content of 37.1%, and its molecular weight measured by GPC was a number average molecular weight of 1450 and a weight average molecular weight of 1500. ¹ H-NMR and ¹³ C-NMR were measured and confirmed to contain Compound B represented by the following chemical formula (4).

<Synthesis Example 3>
Synthesis of poly {γ- (5-norbornene-2,3-imido) propylsilsesquioxane} (Compound C) A 300 mL four-necked flask equipped with a stirrer, a temperature sensor and a condenser tube was previously dried with molecular sieve. 35.1 g of diglyme and 30.8 g of 3-aminopropyltrimethoxysilane were added, and the temperature was raised to 100 ° C. under a flow of dry nitrogen while stirring to remove moisture in the system. Next, 28.2 g of 5-norbornene-2,3-dicarboxylic acid anhydride was added in four portions over 30 minutes while maintaining the reaction solution temperature at 100 ° C. It was confirmed by high performance liquid chromatography that 5-norbornene-2,3-dicarboxylic anhydride was completely consumed in 9 hours after the completion of the addition.
Subsequently, 9.3 g of deionized water was added all at once, and the temperature was raised so that by-product methanol was refluxed in the cooling pipe. After holding at 95 ° C. for 10 hours, the cooling pipe was replaced with a partial condenser and the temperature was raised again. The reaction liquid temperature was allowed to reach 120 ° C. over 3 hours while collecting by-product methanol and condensed water. When the temperature reached 120 ° C., 1.4 g of pyridine was added, and the temperature was raised as it was. The temperature reached 160 ° C. over 3 hours while collecting condensed water, and the temperature was kept at the same temperature for 2 hours and cooled to room temperature.
The reaction product was a dark brown high-viscosity liquid with a non-volatile content of 58.2%. When the molecular weight was measured by GPC, the number-average molecular weight was 2340 and the weight-average molecular weight was 2570. ¹ H-NMR and ¹³ C-NMR were measured, and it was confirmed that the compound C represented by the following chemical formula (5) was contained.

<Synthesis Example 4>
Synthesis of cage-like {γ- (5-norbornene-2,3-imido) propylsilsesquioxane} (compound D) In a 500 mL four-necked flask equipped with a stirrer, a temperature sensor, and a cooling tube, dried in advance with a molecular sieve. 87.9 g of the diglyme and 142.5 g of 3-aminopropyltrimethoxysilane were added, and the temperature was raised to 100 ° C. under a flow of dry nitrogen while stirring to remove moisture in the system. Next, 131.8 g of 5-norbornene-2,3-dicarboxylic anhydride was added in four portions over 30 minutes while maintaining the reaction solution temperature at 100 ° C. It was confirmed by high performance liquid chromatography that 5-norbornene-2,3-dicarboxylic anhydride was completely consumed in 9 hours after the completion of the addition.
Subsequently, 42.9 g of deionized water was added all at once, and the temperature was raised so that by-product methanol was refluxed in the cooling pipe. After holding at 95 ° C. for 10 hours, the temperature was raised again by replacing the cooling pipe with a partial condenser. The reaction liquid temperature was allowed to reach 120 ° C. over 3 hours while collecting by-product methanol and condensed water. When reaching 120 ° C., 0.65 g of cesium carbonate was added and the temperature was raised as it was, reaching 160 ° C. over 3 hours while collecting condensed water, holding at that temperature for 2 hours, and cooling to room temperature. The precipitate was collected by charging and dried to obtain Compound D. Compound D was confirmed to be a cage {γ- (5-norbornene-2,3-imido) propylsilsesquioxane} represented by the following chemical formula (6) from the results of analysis by FT-IR and NMR. When the molecular weight was measured by GPC, the number average molecular weight Mn was 2,340, the weight average molecular weight Mw was 2,570, and the molecular weight distribution Mw / Mn was 1.10.

<Comparative Synthesis Example 1>
Synthesis of ladder-like poly (3-aminopropyl) silsesquioxane triiodide salt (Compound F) In a 300 mL beaker, 8.695 g of 3-aminopropyltrimethoxysilane and 150 mL of 0.5 mol / L hydrochloric acid were added. The mixture was stirred with a magnetic stirrer for 2 hours at room temperature. After that, it was heated at 60 ° C. on five disposable trays with a capacity of 50 mL, and then heated in an oven at 100 ° C. for 10 hours to completely evaporate residual hydrogen chloride, water and methanol. Step of dissolving the obtained plate-like solid content in 50 mL of purified water in a 300 mL beaker, adding 100 mL of acetone while stirring, collecting the precipitate by decantation, and further adding 100 mL of methanol to the recovered product and washing The last was washed with 100 mL of acetone and dried under reduced pressure. The yield of the dried product is 3.667 g, which is consistent with the identification result of Non-Patent Document 2 from the analysis results by FT-IR, NMR and XRD, and ladder-like poly (3-aminopropyl) silsesquioxane hydrochloride It was confirmed that. In GPC measurement, the number average molecular weight Mn was 3,200, the weight average molecular weight Mw was 5,760, and the molecular weight distribution Mw / Mn was 1.80.
Next, an anion exchange resin (product name “Amberlite IRA-900”, manufactured by Organo Co., Ltd.) is packed in a column having a diameter of 2 cm and a length of 40 cm, and 50 mL of a 1.0 mol / L potassium iodide aqueous solution is passed through it. The anion species of the anion exchange resin were replaced with iodide ions by washing with 150 mL of purified water. Ladder-like poly (3-aminopropyl) silsesquioxane hydrochloride (0.733 g) was dissolved in 30 mL of purified water, charged into this column, and collected in an Erlenmeyer flask. The recovered liquid was subjected to column treatment again 5 times and freeze-dried to obtain 0.9010 g of compound E. From the result of elemental analysis of Compound E by ion chromatography, no chloride ion was confirmed. Instead, the same molar amount of iodide ion was detected, and Compound E was a ladder-like poly (3-aminopropyl) silsesquioxane iodide. It was confirmed to be a chloride salt. When the molecular weight was measured by GPC, the number average molecular weight Mn was 3,040, the weight average molecular weight Mw was 5,290, and the molecular weight distribution Mw / Mn was 1.74. Subsequently, 0.0426 mg of iodine is dissolved in 5 mL of diglyme, 0.020 mg of compound E is added thereto, and the mixture is stirred at room temperature for 2 hours, whereby ladder-like poly (3-aminopropyl) silsesquioxane triiodide salt (compound A diglyme solution of F) was obtained.

<Heat resistance evaluation>
The heat resistance evaluation of the compounds A to D and F was performed using TG-DTA. About 10 mg of each sample was weighed and heated to 500 ° C. at a rate of temperature increase of 10 ° C./min under a nitrogen flow of 100 mL / min, and the temperature at which the weight loss rate was 5% (Td 5%) was determined. A temperature of Td 5% is shown in Table 1.

<CNT dispersibility evaluation>
Evaluation of CNT dispersibility of the compounds A to D and F was performed as follows.
Compound A to D, F 0.1 g, MWCNT (manufactured by Tokyo Chemical Industry Co., Ltd., diameter 10 nm, total length 1 to 2 μm) 0.1 g are weighed into a 50 mL glass vial, and further 10 mL of N-methylpyrrolidone is added to the ultrasonic homogenizer Was used for dispersion processing. The homogenizer dispersion conditions were an output of 150 W, a treatment liquid temperature of 40 ° C. or less, and a treatment time of 1 hour.

The dispersion stability of the obtained dispersion was allowed to stand at room temperature for 24 hours and evaluated by visually confirming the change in the dispersion state of MWCNT. The determination of the dispersion state was as follows. The results are shown in Table 2.
◎: Dispersion is uniform without separation and there is no precipitate ○: Dispersion is uniform with little separation, but dispersion is uniform ×: Dispersion is divided into two layers, black and transparent, with sediment at the bottom

Compound F used in Comparative Examples 1 and 2 has a sufficiently large number average molecular weight of 3000 or more. However, when Td5% is 300 ° C. or lower, the heat resistance is low, and the MWCNT dispersibility is not so high. As in Non-Patent Document 1, it is presumed that I ₂ or the like needs to be added as a dispersion aid.
On the other hand, the compounds A, B, C, and D used in Examples 1 to 8 have a Td of 5% exceeding 350 ° C. due to the silsesquioxane type inorganic structure of the main skeleton and the imide skeleton of the side chain. The sex was very high. Moreover, it was excellent in the dispersion state of the MWCNT dispersion.

Claims (2)

A conductive carbon material-containing composition comprising a polysiloxane compound having a nonionic substituent in a side chain and a conductive carbon material. 2. The conductive carbon material-containing material according to claim 1, wherein the polysiloxane compound has at least one polysiloxane skeleton structure selected from the group consisting of a chain, a network, a ring, a cage, and a cubic. Composition.