Crystalline polymer additives and filler-containing compositions

Abstract

To provide a crystalline polymer additive that can achieve both dispersibility and dispersion stability of the filler. [Solution] A crystalline polymer additive having a polycyclic aromatic ring in its molecule and a melting point between 0°C and 100°C.

Description

[Technical Field]

[0001] The present invention relates to crystalline polymer additives and filler-containing compositions containing the same. [Background technology]

[0002] With the increasing density and integration of electronic materials, thermally conductive resin compositions have been proposed that are filled with thermally conductive fillers such as aluminum oxide, zinc oxide, boron nitride, and graphite to efficiently dissipate the heat generated from electronic components. In these cases, polymer additives with dispersion properties are often used to enhance the affinity between the filler and the matrix, such as solvents and resins, and to improve the dispersibility or dispersion stability of the filler. Here, dispersibility refers to the property of fillers to quickly disperse in the matrix when shear force is applied (at high shear rates), while dispersion stability refers to the property of fillers to remain stably dispersed in the matrix without settling when left at rest (at low shear rates). To achieve dispersibility, the fillers need to separate at high shear rates, while to achieve dispersion stability, the fillers need to interact and flocculate (soft aggregate) at low shear rates (Non-Patent Literature 1).

[0003] As for polymer dispersants, for example, Patent Document 1 discloses an invention relating to a terminal diol type silicone-based dispersant that can impart excellent filler dispersibility in liquids. For fillers to interact with each other, interactions between fillers and additives, and between additives themselves, are important. One form of interaction is high crystallinity (high intermolecular forces), and Non-Patent Document 2 describes an invention relating to a highly crystalline polyacrylate copolymer having long-chain alkyl groups in its side chains. In addition, in Non-Patent Document 3, regarding carbon nanotubes, which are fillers of a π-conjugated system (fillers having a six-membered ring atomic structure as a structural unit), solubilization in water and organic solvents has been investigated by utilizing the van der Waals force (intermolecular force) of additives. Furthermore, in Patent Document 2, a pigment dispersant using a (meth)acrylic polymer having an acid anhydride group in one terminal region is disclosed. The dispersant is a dispersant that utilizes acid-base interaction.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Non-Patent Documents

[0005]

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0006] In a slurry obtained by mixing a filler and a matrix (solvent / resin), in order to achieve both good dispersibility and dispersion stability of the filler, it is necessary to weakly interact between the fillers and to break them up during shearing. That is, in order to achieve both good dispersibility and dispersion stability, the value of [viscosity at low shear rate] / [viscosity at high shear] (TI value, thixotropic index) needs to be large. The terminal diol type silicone-based dispersant disclosed in the above Patent Document 1 has a low TI value, and it is difficult to achieve both good dispersibility and dispersion stability. In the above Non-Patent Document 2, there is a polymer that interacts with a long-chain alkyl group in the side chain; in the above Non-Patent Document 3, there is one that utilizes van der Waals force as a dispersant for carbon nanotubes; and in Patent Document 2, there is one that utilizes acid-base interaction. However, none of the documents have considered achieving both good dispersibility and dispersion stability.

[0007] Therefore, an object of the present invention is to provide a crystalline polymer additive that can achieve both good dispersibility and dispersion stability of a filler in a slurry obtained by mixing a filler and a matrix (solvent / resin).

Means for Solving the Problems

[0008] As a result of intensive studies, the present inventors have found that the above problems can be solved by a crystalline polymer additive having a polycyclic aromatic ring structure in the molecule and having a melting point of 0°C or higher and 100°C or lower, and have completed the present invention.

[0009] That is, the present invention relates to the following [1] to

[11] . [1] A crystalline polymer additive having a polycyclic aromatic ring in the molecule and having a melting point of 0°C or higher and 100°C or lower. [2] The crystalline polymer additive according to [1] above, which is esters, ethers, amides, or siloxanes. [3] The crystalline polymer additive according to [1] or [2] above, which has a (meth)acrylate skeleton or a siloxane skeleton. [4] A crystalline polymer additive according to any of [1] to [3] above, which is a copolymer represented by formula (1) or a polysiloxane compound represented by formula (2). [ka] The copolymer represented by formula (1) has a long-chain alkyl group-containing unit represented by (1a), a hydrophilic group-containing unit represented by (1b), and a polycyclic aromatic ring-containing unit represented by (1c), where R1 to R3 are each independently a hydrogen atom or a methyl group, X is an alkyl group having 14 to 22 carbon atoms, Y is a polyalkylene glycol chain, Z is an atomic group containing a polycyclic aromatic ring, m is between 1 and 200, n is between 1 and 50, and l is between 1 and 30. [ka] In equation (2), R4~R 15 Each of these is independently a methyl group, an atomic group containing 14 or more carbon atoms, or an atomic group containing a polycyclic aromatic ring. R4~R 15 In this configuration, at least one atom group contains 14 or more carbon atoms, and at least one atom group contains a polycyclic aromatic ring. j is between 1 and 100, k is between 1 and 20, and i is between 1 and 20. [5] A crystalline polymer additive according to any of [1] to [4] above, having a number average molecular weight of 4,000 or more and 100,000 or less. [6] The crystalline polymer additive according to any one of [1] to [5] above, wherein the polycyclic aromatic ring has a fused ring structure in which four or more aromatic rings are fused together. [7] A crystalline polymer additive according to any of [1] to [6] above, having a maximum fluorescence peak in the range of 370 nm to 410 nm. [8] A crystalline polymer additive according to any of [1] to [7] above, having two maximum UV absorption peaks in the range of 320 nm to 350 nm. [9] A filler-containing composition comprising a crystalline polymer additive as described in any of [1] to [8] above, a filler, and a matrix which is at least one of a resin or a solvent.

[10] The filler-containing composition according to [9] above, wherein the filler is a thermally conductive filler.

[11] The filler-containing composition according to [9] or

[10] above, wherein the resin comprises a curable resin, and the curable resin comprises an epoxy compound. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a crystalline polymer additive that can achieve both dispersibility and dispersion stability of the filler. [Modes for carrying out the invention]

[0011] [Crystalline polymer additives] The crystalline polymer additive of the present invention has a polycyclic aromatic ring structure in its molecule and a melting point between 0°C and 100°C. The crystalline additive of the present invention can enhance both the dispersibility and dispersion stability of the filler by being incorporated into a slurry of a filler and a matrix (solvent / resin). This is thought to be because the crystalline polymer additive of the present invention has a polycyclic aromatic ring structure and exhibits a specific melting point range, making it easily compatible with the matrix. Furthermore, it forms weak interactions (pseudo-crosslinking) between the fillers, resulting in high dispersion stability when the slurry of the fillers and matrix is ​​left standing, and increased dispersibility when shear is applied. In this specification, dispersibility refers to the property of fillers to disperse quickly in the matrix when shear force is applied (at high shear rates), and dispersion stability refers to the property of fillers to remain stably dispersed in the matrix without settling when left at rest (at low shear rates).

[0012] The crystalline polymer additive of the present invention has a melting point of 0°C or higher and 100°C or lower. If the melting point of the crystalline polymer additive is below 0°C, the interaction between the additives in the matrix is ​​weak, and therefore the dispersion stability of the filler decreases. On the other hand, if the melting point of the crystalline polymer additive is above 100°C, the interaction between the additives is too strong, making them incompatible with the matrix, and thus making it difficult to improve the dispersibility of the filler. The crystalline polymer additive in this invention has a melting point between 0°C and 100°C, which allows for interaction between the filler and the additive, as well as moderate interaction between the additives themselves. As a result, it is believed that weak interactions (pseudo-crosslinking) are formed between the fillers, thereby improving the dispersibility and dispersion stability of the fillers. From the viewpoint of improving the dispersibility and dispersion stability of the filler, the melting point of (B) the crystalline polymer additive is preferably 30°C to 75°C, and more preferably 45°C to 65°C.

[0013] The melting point of crystalline polymer additives can be easily adjusted to the above range by having a structure within the molecule that facilitates crystal formation. The structure of crystalline polymer additives is not particularly limited as long as the melting point is within the above range, but for example, using a crystalline polymer additive having a long-chain alkyl group (e.g., an alkyl group with 14 to 22 carbon atoms) as described later makes it easier to adjust the melting point to the above range, and the height of the melting point can be adjusted by changing the number of carbon atoms in the long-chain alkyl group. The melting point of crystalline polymer additives is determined from the temperature of the endothermic peak top associated with the melting of the crystal, as measured by differential scanning calorimeter (DSC). Furthermore, the presence or absence of crystalline properties can be determined by the presence or absence of a melting point.

[0014] The crystalline polymer additive of the present invention has a polycyclic aromatic ring in its molecule. This enhances the compatibility of the crystalline polymer additive with the matrix and improves its interaction with fillers, thereby improving its dispersibility. The polycyclic aromatic ring structure of the crystalline polymer dispersant particularly enhances the dispersibility of π-conjugated fillers. π-conjugated fillers are fillers that have a six-membered ring atomic structure as their constituent unit, such as boron nitride fillers and carbon materials.

[0015] The polycyclic aromatic ring is preferably one that has a fused ring structure in which multiple aromatic rings (6-membered rings) are fused together. Examples of the polycyclic aromatic rings mentioned above include compounds having a fused ring structure such as naphthalene, anthracene, phenanthrene, triphenylene, pyrene, tetracene, picene, perylene, pentaphene, pentacene, and hexaphene. Among the compounds having a fused ring structure, compounds having a fused ring structure in which four or more aromatic rings are fused are preferred, and pyrene is particularly preferred from the viewpoint of solubility in the matrix and interaction with fillers. Compounds having a fused ring structure may have at least one of the hydrogen atoms constituting the compound substituted with a substituent. Examples of substituents include organic groups having 1 to 10 carbon atoms.

[0016] The crystalline polymer additive is preferably an ester, ether, amide, or siloxane. Esters are polymers having an ester in their main chain, such as polymers with structural units derived from caprolactone, or polymers having a (meth)acrylate skeleton. Ethers are polymers having an ether in their main chain. Amides are polymers having an amide in their main chain, such as polymers with structural units derived from caprolactam. Siloxanes are polymers having a siloxane skeleton. (Meth)acrylate means methacrylate or acrylate.

[0017] From the viewpoint of improving dispersibility and dispersion stability, the crystalline polymer additive preferably has a (meth)acrylate skeleton or a siloxane skeleton, and more preferably has a (meth)acrylate skeleton.

[0018] <(Meth)acrylate skeleton-containing crystalline polymer additive> From the viewpoint of improving dispersibility and dispersion stability, the crystalline polymer additive is preferably a copolymer represented by the following formula (1). The copolymer represented by formula (1) is a crystalline polymer additive having a (meth)acrylate skeleton. [ka] The copolymer represented by formula (1) has a long-chain alkyl group-containing unit represented by (1a), a hydrophilic group-containing unit represented by (1b), and a polycyclic aromatic ring-containing unit represented by (1c), where R1, R2, and R3 are each independently a hydrogen atom or a methyl group, X is an alkyl group having 14 to 22 carbon atoms, Y is a polyalkylene glycol chain, Z is an atomic group containing a polycyclic aromatic ring, m is between 1 and 200, n is between 1 and 50, and l is between 1 and 30.

[0019] (Long-chain alkyl group-containing unit) The copolymer represented by formula (1) has a long-chain alkyl group-containing unit represented by (1a). Having a long-chain alkyl group-containing unit results in a crystalline polymer additive and a polymer additive having the predetermined melting point described above. Furthermore, the presence of a long-chain alkyl group facilitates interaction between additives due to van der Waals forces, leading to improved dispersion stability. Additionally, polymer additives with long-chain alkyl groups can also act on fillers through van der Waals forces, improving dispersibility. X is a long-chain alkyl group, having 14 to 22 carbon atoms. From the viewpoint of improving the dispersibility and dispersion stability of the filler, X is preferably an alkyl group having 16 to 22 carbon atoms, and more preferably an alkyl group having 20 to 22 carbon atoms. Furthermore, the long-chain alkyl group may be linear or branched, but it is preferable that it be linear. m represents the number of long-chain alkyl group-containing units, which is between 1 and 200, preferably between 5 and 100, and more preferably between 20 and 50.

[0020] The copolymer represented by formula (1) may have two or more long-chain alkyl group-containing units represented by (1a). For example, it may have multiple long-chain alkyl group-containing units represented by (1a) having different numbers of carbon atoms X. In this case, the above-mentioned m is the total number of units of the multiple long-chain alkyl group-containing units represented by (1a).

[0021] (Hydrophilic group-containing unit) The copolymer represented by formula (1) has a hydrophilic group-containing unit represented by formula (1b). The presence of hydrophilic group-containing units improves the compatibility of crystalline polymer additives with the matrix, and also enhances the interaction of crystalline polymer additives with fillers, thereby improving dispersibility. In formula (1b), Y is a polyalkylene glycol chain, preferably a polyethylene glycol chain.

[0022] Y is preferably an alkylene glycol chain represented by the following formula (3). [ka] In equation (3), R 18 g is an alkylene group having 2 to 4 carbon atoms, preferably an alkylene group having 2 to 3 carbon atoms, and more preferably an alkylene group having 2 carbon atoms (i.e., an ethylene group). g is an oxyalkylene group (-R 18 R is the number of repetitions of -0-), preferably 1 to 50, more preferably 6 to 12. 19 This is a hydrogen atom or a methyl group, preferably a hydrogen atom. In formula (3), * represents a bond that connects to the oxygen atom in the hydrophilic group-containing unit represented by (1b).

[0023] In formula (1b), n represents the number of hydrophilic group-containing units, which is between 1 and 50, preferably between 3 and 30, and more preferably between 6 and 15.

[0024] (Polycyclic aromatic ring-containing unit) The copolymer represented by formula (1) has a polycyclic aromatic ring-containing unit represented by (1c). The presence of the polycyclic aromatic ring-containing unit increases the compatibility of the crystalline polymer additive with the matrix and enhances the interaction with the filler, thereby improving dispersibility. When a crystalline polymer dispersant has a polycyclic aromatic ring unit, it particularly improves the dispersibility of π-conjugated fillers through π-π interactions. π-conjugated fillers are fillers that have a six-membered ring atomic structure as their constituent unit, such as boron nitride fillers and carbon materials.

[0025] Z is an atomic group containing a polycyclic aromatic ring. The atomic group containing a polycyclic aromatic ring is not particularly limited; for example, it may consist only of a polycyclic aromatic ring, or it may be a compound composed of a polycyclic aromatic ring and an organic group having 1 to 10 carbon atoms. Preferably, the polycyclic aromatic ring has a fused ring structure in which multiple aromatic rings (6-membered rings) are fused together. Examples of the polycyclic aromatic rings mentioned above include compounds having a fused ring structure such as naphthalene, anthracene, phenanthrene, triphenylene, pyrene, tetracene, picene, perylene, pentaphene, pentacene, and hexaphene. Among the compounds having a fused ring structure, compounds having a fused ring structure in which four or more aromatic rings are fused are preferred, and pyrene is particularly preferred from the viewpoint of solubility in the matrix and interaction with fillers. Compounds having a fused ring structure may have at least one of the hydrogen atoms constituting the compound substituted with a substituent. Examples of substituents include organic groups having 1 to 10 carbon atoms.

[0026] In formula (1), l represents the number of polycyclic aromatic ring-containing units, which is between 1 and 30, preferably between 2 and 20, and more preferably between 3 and 10.

[0027] In the polycyclic aromatic ring-containing unit represented by (1c), it is preferable that the polycyclic aromatic ring in Z is bonded to the oxygen atom of (1c) via, for example, 1 to 4 alkylene chains, preferably methylene chains. The polycyclic aromatic ring-containing unit represented by (1c) is preferably a unit represented by the following formula (4). [ka] R3 and l are equivalent to those in equation (1). 20 These are polycyclic aromatic rings, such as naphthalene, anthracene, phenanthrene, triphenylene, pyrene, tetracene, picene, perylene, pentaphene, pentacene, and hexaphene. Among them, R 20 A unit represented by the following formula (5), in which is pyrene, is preferred.

[0028] [ka] In equation (5), R3 and l are equivalent to those in equation (1).

[0029] The copolymer represented by formula (1) may have other units besides the long-chain alkyl group-containing unit represented by (1a), the hydrophilic group-containing unit represented by (1b), and the polycyclic aromatic ring-containing unit represented by (1c), but it is preferable that it consists only of the three types of units (1a), (1b), and (1c).

[0030] The copolymer represented by formula (1) can also be represented as shown in formula (6) below. [ka] In formula (6), R1-R3, m, n, l, X, Y, and Z are equivalent to those in formula (1). The asterisks (*) at both ends represent bonds. The asterisks (*) typically bond to groups (generally organic groups with 1-20 carbon atoms) derived from reagents such as polymerization initiators used in the production of polymers represented by formula (6). The arrangement of the long-chain alkyl group-containing units, hydrophilic group-containing units, and aromatic ring-containing units in the copolymer is not particularly limited and may be in blocks or random.

[0031] A crystalline polymer additive having a (meth)acrylate skeleton may also have a polysiloxane structure. That is, the crystalline polymer additive may be a copolymer having a (meth)acrylate skeleton and a polysiloxane structure in its side chains. Copolymers having a (meth)acrylate skeleton and a polysiloxane structure in the side chain include, for example, copolymers containing a polysiloxane-containing unit represented by (1d) in formula (7). [ka] In equation (7), R 17 is a hydrogen atom or a methyl group, and h is the number of units in the copolymer of polysiloxane-containing units, ranging from 1 to 10. A is a group containing the polysiloxane structure. A may be a monovalent group in the polysiloxane compound shown in formula (2) described later, obtained by removing one hydrogen atom from the alkyl group bonded to the silicon atom.

[0032] A copolymer having a (meth)acrylate skeleton and a polysiloxane structure in its side chain comprises a polysiloxane-containing unit represented by (1d) and may also contain any unit selected from the long-chain alkyl group-containing unit represented by (1a), the hydrophilic group-containing unit represented by (1b), and the polycyclic aromatic ring-containing unit represented by (1c).

[0033] The copolymer containing each of the units (1a), (1b), and (1c) described above, or the copolymer containing the unit (1d) described above, is obtained by polymerizing a (meth)acrylate-based monomer for forming each unit.

[0034] When obtaining the copolymer represented by the above formula (1), it can be obtained by copolymerizing the following monomers (a), monomer (b), and monomer (c).

Chemical formula

[0035] Also, when producing a copolymer containing the unit (1d), it is advisable to copolymerize at least any one of the above monomers (a), monomer (b), and monomer (c) with the following monomer (d).

Chemical formula

[0036] <Crystalline polymer additive having a siloxane skeleton> (B) From the viewpoint of improving dispersibility and dispersion stability, the crystalline polymer additive is preferably an additive having a siloxane skeleton.

[0037] The additive having a siloxane skeleton is a compound having a polysiloxane structure in the main chain, and is preferably a polysiloxane compound represented by the following formula (2).

Chemical formula

[0038] The polysiloxane compound represented by formula (2) has an atomic group containing 14 or more carbon atoms, thereby becoming a polymer additive having the predetermined melting point described above. Furthermore, having an atomic group containing 14 or more carbon atoms facilitates interaction between polymer additives due to van der Waals forces, thus increasing dispersion stability. In addition, polymer additives having an atomic group containing 14 or more carbon atoms can also act on fillers through van der Waals forces, improving dispersibility.

[0039] The atomic group containing 14 or more carbon atoms as described above is preferably an alkyl group having 14 or more carbon atoms, or a group represented by formula (8) described later. The alkyl group having 14 or more carbon atoms is preferably an alkyl group having 14 to 22 carbon atoms, more preferably an alkyl group having 16 to 22 carbon atoms, and even more preferably an alkyl group having 20 to 22 carbon atoms.

[0040] A group of atoms containing 14 or more carbon atoms may be a group represented by formula (8) as follows: [ka] In equation (8), R 20 R is an alkyl group having 14 to 22 carbon atoms, preferably an alkyl group having 16 to 22 carbon atoms, and more preferably an alkyl group having 20 to 22 carbon atoms. 21 is a hydrogen atom or a methyl group. * is a bond that connects to the silicon atom in formula (2).

[0041] In the atomic group containing polycyclic aromatic rings in the polysiloxane compound represented by formula (2), the types of polycyclic aromatic rings are as described above. The atomic group having the polycyclic aromatic ring is preferably a (meth)acrylate having a polycyclic aromatic ring, and more preferably one represented by formula (9). [ka] In equation (9), R 22 It is a group containing a polycyclic aromatic ring. The types of polycyclic aromatic rings are as described above. Also, R 22 R may be Z as explained in equation (1). 23 is a hydrogen atom or a methyl group. * is a bond that connects to the silicon atom in formula (2).

[0042] The compound represented by formula (2) can be obtained, for example, by a hydrosilylation reaction between a polysiloxane having a hydrosilyl group (SiH group) and an atomic group containing 14 or more carbon atoms having an alkenyl group and an atomic group having a polycyclic aromatic ring having an alkenyl group.

[0043] The number-average molecular weight of the crystalline polymer additive is preferably 4,000 to 100,000, more preferably 5,000 to 50,000, and even more preferably 10,000 to 25,000. When the number-average molecular weight of the crystalline polymer additive is above the lower limit, the dispersion stability of the filler tends to improve. When the number-average molecular weight of the crystalline polymer additive is below the upper limit, the compatibility of the crystalline polymer additive with the matrix increases, and the dispersibility of the filler tends to improve. The number-average molecular weight of crystalline polymer additives can be measured by gel permeation chromatography (GPC) and is expressed as a value on a standard polystyrene basis.

[0044] The crystalline polymer additive of the present invention preferably has a maximum fluorescence peak within the range of 370 nm to 410 nm. Having the maximum fluorescence peak within this range facilitates interaction with π-conjugated fillers and suppresses the stacking of aromatic rings such as condensed ring compounds. As a result, the solubility and dispersibility of the crystalline polymer additive in the matrix (resin / solvent) are improved. The maximum fluorescence peak is preferably in the range of 380 nm to 410 nm, more preferably 390 nm to 410 nm, and even more preferably 395 nm or more and 405 nm or less. The maximum fluorescence peak can be adjusted by the type of aromatic ring present in the crystalline polymer additive. Furthermore, the maximum fluorescence peak can be identified from the fluorescence spectrum of the crystalline polymer additive. More specifically, the fluorescence spectrum is obtained by sandwiching the crystalline polymer additive between glass slides to a thickness of 40 μm under excitation wavelength of 339 nm, and the wavelength at which the intensity in this fluorescence spectrum is maximum is the maximum fluorescence peak.

[0045] The crystalline polymer additive of the present invention preferably has two maximum UV absorption peaks in the range of 320 nm to 350 nm when its ultraviolet absorption (UV) spectrum is measured. Crystalline polymer additives having two maximum UV absorption peaks in such a specific wavelength range tend to improve the dispersibility of π-conjugated fillers and also tend to have higher solubility in the matrix. The ultraviolet absorption spectrum of crystalline polymer additives can be adjusted depending on the type of aromatic ring present in the additive.

[0046] [Filler-containing composition] In the present invention, a filler-containing composition can be provided, comprising the above-mentioned crystalline polymer additive, a filler, and a matrix which is at least one of a resin or a solvent.

[0047] (Filler-containing composition: Crystalline polymer additive) As explained above, crystalline polymer additives are omitted from this explanation. The content of the crystalline polymer additive in the filler-containing composition of the present invention is preferably 50% by mass or less, more preferably 30% by mass or less, even more preferably 25% by mass or less, and preferably 1% by mass or more, more preferably 2% by mass or more, and even more preferably 4% by mass or more, based on 100% by mass of the matrix, from the viewpoint of improving the dispersibility and dispersion stability of the filler.

[0048] (Filler-containing composition: Filler) The filler-containing composition of the present invention contains a filler. The filler may be a thermally conductive filler having thermal conductivity or a non-thermally conductive filler not having thermal conductivity, but from the viewpoint of applying the filler-containing composition to heat dissipation applications, a thermally conductive filler is preferred. Here, a thermally conductive filler is a filler that has thermal conductivity, and preferably has a thermal conductivity of 10 W / m·K or higher.

[0049] Examples of thermally conductive fillers include fillers with a six-membered ring atomic structure as the constituent unit (π-conjugated fillers), metal nitride fillers, metal oxide fillers, metal fillers, and carbon-based fillers. Among these, fillers with a six-membered ring atomic structure as the constituent unit, metal nitride fillers, metal oxide fillers, and metal fillers are preferred, and fillers with a six-membered ring atomic structure as the constituent unit are particularly preferred. Generally, fillers with a six-membered ring atomic structure as the constituent unit tend to have poor dispersibility and dispersion stability, but by using the crystalline polymer additive described above in the present invention, dispersibility and dispersion stability can be improved.

[0050] Examples of fillers that have a six-membered ring atomic structure as their constituent unit include boron nitride fillers or carbon materials. Examples of boron nitride fillers include boron nitride, boron nitride nanotubes, and boron nitride nanosheets. Examples of carbon materials include carbon fibers, graphite, graphene, and carbon nanotubes.

[0051] Examples of metal nitride fillers include aluminum nitride. Examples of metal oxide fillers include alumina, magnesia, titania, and zinc oxide. Alternatively, the metal oxide filler may be a filler whose surface is coated with one or more materials selected from alumina, silica, magnesia, titania, and zinc oxide. Examples of metal fillers include copper, silver, gold, and aluminum. Alternatively, the metal filler may be a filler whose surface is coated with one or more materials selected from copper, silver, gold, and aluminum. Examples of carbon-based fillers include diamond and polymer-based fillers.

[0052] The average particle size of the filler is not particularly limited, but is preferably between 1 μm and 100 μm, more preferably between 1 μm and 50 μm, and more preferably between 1 μm and 10 μm. The average particle size refers to the particle size at 50% volume integration (D50) in the particle size distribution of the filler determined by laser diffraction and scattering.

[0053] The filler content in the filler-containing composition is, for example, 10 to 1000 parts by mass, preferably 20 to 500 parts by mass, and more preferably 30 to 300 parts by mass, per 100 parts by mass of matrix.

[0054] <Matrix> The filler-containing composition of the present invention includes a matrix, which is at least one of a solvent or a resin. The matrix may contain both a solvent and a resin.

[0055] Examples of solvents include toluene, ethyl acetate, methyl ethyl ketone, tetrahydrofuran, acetone, cyclohexanone, cyclohexane, n-propanol, 2-propanol, ethanol, methanol, methyl isobutyl ketone, cyclopentanone, N-methylpyrrolidone, n-hexane, pentane, and heptane.

[0056] Examples of resins include curable resins, thermoplastic resins, and elastomer resins. Examples of curable resins include epoxy resins, silicone resins, urethane resins, phenolic resins, unsaturated polyester resins, polyimide resins, and oxetane resins. Examples of thermoplastic resins include polyolefin resins such as polypropylene resin, polyethylene resin, poly(1-)butene resin, and polypentene resin, polyester resins such as polyethylene terephthalate, polystyrene resin, acrylonitrile-butadiene-styrene (ABS) resin, ethylene vinyl acetate copolymer (EVA), (meth)acrylic resin, polyamide resin, and polyvinyl chloride resin (PVC).

[0057] Examples of elastomer resins include acrylonitrile butadiene rubber, ethylene-propylene-diene rubber, ethylene-propylene rubber, natural rubber, polybutadiene rubber, and polyisoprene rubber. These elastomer resins may be liquid elastomers that are liquid at room temperature (23°C) and normal pressure (1 atm), solids, or mixtures thereof. Furthermore, thermoplastic elastomers such as polyester-based thermoplastic elastomers, polyurethane-based thermoplastic elastomers, and styrene-based thermoplastic elastomers can also be used as elastomer resins.

[0058] Among the resins mentioned above, curable resins are preferred. Furthermore, curable resins are preferably those that contain epoxy compounds, and more preferably those that contain both epoxy compounds and a curing agent. Examples of epoxy compounds include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol S type epoxy compounds, phenol novolac type epoxy compounds, biphenyl type epoxy compounds, biphenyl novolac type epoxy compounds, biphenol type epoxy compounds, naphthalene type epoxy compounds, fluorene type epoxy compounds, phenol aralkyl type epoxy compounds, naphthol aralkyl type epoxy compounds, dicyclopentadiene type epoxy compounds, anthracene type epoxy compounds, epoxy compounds having an adamantane skeleton, epoxy compounds having a tricyclodecane skeleton, naphthylene ether type epoxy compounds, and epoxy compounds having a triazine core as their skeleton.

[0059] Examples of curing agents include phenol compounds (phenol curing agents), amine compounds (amine curing agents), imidazole compounds, acid anhydrides, cyanate ester compounds, carbodiimide compounds, and imide oligomers. Imide oligomers are compounds having an imide skeleton in their main chain, and preferably compounds having an aromatic ring in their skeleton. The imide oligomer has a reactive functional group at one or both ends of the molecule that can react with the curable resin, and it is preferable that the reactive functional group is an acid anhydride group, an amino group, or a hydroxyl group. The amino group is not particularly limited and may be a primary amino group, a secondary amino group, or a tertiary amino group. The hydroxyl group may be a phenolic hydroxyl group or a hydroxyl group other than a phenolic hydroxyl group.

[0060] The matrix is ​​preferably compatible with crystalline polymer additives. By being compatible with the matrix, the crystalline polymer additive can effectively function as a dispersant, thereby improving the dispersibility and dispersion stability of the filler. Compatibility means that when the matrix and the crystalline polymer additive are mixed, the crystalline polymer additive completely dissolves in the matrix.

[0061] The content of (C) matrix in the filler-containing composition of the present invention is, for example, 10 to 90% by mass, preferably 20 to 80% by mass, and more preferably 30 to 70% by mass, based on the total amount of the filler-containing composition.

[0062] The filler-containing composition of the present invention exhibits excellent dispersibility and dispersion stability of the filler. Therefore, the viscosity of the filler-containing composition at a shear rate of 0.001 (1 / s) is η(0.001 sec -1 ), the viscosity at a shear rate of 10 (1 / s) is η (10 sec -1 It is preferable that the ratio (TI value: formula below) when ) is set to a certain level or higher. Specifically, the TI value is preferably 100 or higher, more preferably 250 or higher, and even more preferably 1000 or higher. The upper limit of the TI value is not particularly limited, but the TI value is, for example, 10000 or less. Note that the TI value may be a value greater than 10000. TI value = η(0.001sec) -1 ) / η(10sec -1 ) The method for measuring the TI value is as described in the examples.

[0063] From the perspective of improving the dispersion stability of fillers, η(0.001sec) -1 ) preferably 1.0 × 10 5 mPa·s or higher, more preferably 3.0 × 10⁻⁶ 4 It is greater than or equal to mPa·s. Also, η(0.001sec) -1 ) For example, 1.0 × 10 8 It is less than or equal to mPa·s. From the perspective of improving the dispersibility of fillers, η(10sec -1 ) preferably 1.0 × 10 5 It is less than or equal to mPa·s, and more preferably 5.0 × 10⁻⁶ 4 It is less than or equal to mPa·s. Also, η(10sec -1 ) is, for example, 1.0 × 10 3 It is above mPa·s.

[0064] As described above, the filler-containing composition of the present invention exhibits excellent dispersibility and dispersion stability of fillers, resulting in superior workability when manufacturing various materials containing fillers. Furthermore, because the filler-containing composition of the present invention exhibits excellent dispersibility and dispersion stability of fillers, it is possible to increase the filler content, making it useful, for example, as a raw material for materials with high heat dissipation properties. [Examples]

[0065] The present invention will be clarified below by providing specific examples and comparative examples of the present invention. However, the present invention is not limited to the following examples.

[0066] The measurement and evaluation methods in the examples and comparative examples are as follows. [Melting point] A 5 mg sample of crystalline polymer additive was used for measurement. Using a differential scanning calorimeter (Hitachi High-Tech Corporation, DSC7000X), the melting point was measured by raising the temperature from -50°C to 175°C at a rate of 10°C / min under a nitrogen atmosphere (1st heating), and the top of the crystal melting peak measured was taken as the melting point value.

[0067] [Molecular weight] The number-average molecular weight of each crystalline polymer additive was measured by GPC under the following conditions. A recycled preparative HPLC system, model LC-9225 NEXT, manufactured by Nippon Analytical Engineering Co., Ltd., was used as the GPC instrument. A LF-604 6.0 × 150 mm column was used, and THF was used as the solvent. Measurements were taken at a crystalline polymer additive concentration of 0.2% by mass, a flow rate of 1.00 mL / min, a pressure of 3.0 MPa, and a temperature of 25°C. Polystyrene samples were used as standard samples.

[0068] [Each ingredient] The matrices and fillers used in the examples and comparative examples are as follows: (Matrix: resin) • Epoxy compound: Bisphenol A type epoxy resin (EXA-850CRP, manufactured by DIC Corporation) • Hardener: IMO (Imido Oligomer) 104 parts by weight of 4,4'-(4,4'-isopropylidene diphenoxy)diphthalic anhydride (manufactured by Tokyo Chemical Industries, Ltd.) was dissolved in 300 parts by weight of N-methylpyrrolidone (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., "NMP"). To the resulting solution, a solution prepared by diluting 28 parts by weight of the dimeramine priamine 1074 (manufactured by Croda) with 100 parts by weight of N-methylpyrrolidone was added, and the mixture was stirred at 25°C for 2 hours to obtain an amic acid oligomer solution. After removing N-methylpyrrolidone under reduced pressure from the obtained amic acid oligomer solution, the mixture was heated at 300°C for 2 hours to obtain an imide oligomer composition (imidization rate 93%).

[0069] (Matrix: Solvent) Cyclohexanone

[0070] (Filler) • Boron nitride (Showa Denko "UHP-1K") π-conjugated filler

[0071] <Example 1> In a reaction vessel fitted with a condenser, 1.2000 g of 1-pyrenylmethyl methacrylate, 9.3361 g of stearyl acrylate, 2.3013 g of polyethylene glycol methacrylate (Mn=360), 0.2154 g of 2-cyano-2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propane, 0.0352 g of 2,2'-azobis(isobutyronitrile), and 17.32 g of toluene were added and stirred. After purging the reaction vessel with nitrogen, the temperature of the reaction vessel was raised to 80 degrees Celsius while stirring, and the reaction was allowed to proceed for 17 hours. After that, the reaction vessel was cooled with ice to stop the reaction, and a copolymer solution was obtained. The obtained reaction solution was purified by adding it dropwise to methanol to obtain the copolymer (crystalline polymer additive) shown in formula (1). The number-average molecular weight of the obtained crystalline polymer additive was 16,400. The polyethylene glycol methacrylate (Mn=360) used as a raw material is such that Y in monomer (b) described herein is an alkylene glycol chain represented by formula (3), and R 18 is an ethylene group, R 19 The hydrogen atom is a monomer with 6 repeating atoms. Polyethylene glycol methacrylate (Mn=360) is shown as EO(360) in the table. Table 1 shows the structure (number of units and number-average molecular weight of each unit) and melting point of the obtained crystalline polymer additives. In the table, C12, C18, etc., represent the number of carbon atoms in the alkyl group of the additive; C12 means 12 carbon atoms, C18 means 18 carbon atoms, and other similar notations are used in the same way. In addition, 1 The above reaction was confirmed to have proceeded by 1H NMR measurement. A JEOL "ECX-400" NMR analyzer was used, with deuterated chloroform as the solvent, under the following conditions: sample concentration 1% by weight, 25°C, measurement frequency 400MHz, and 8 integration cycles. The reaction progress was similarly confirmed for the other examples and comparative examples. 1 This was confirmed by 1H NMR measurement. The obtained crystalline polymer additives were evaluated as follows.

[0072] [Preparation of evaluation samples] The solvent shown in Table 1 as the matrix and the obtained crystalline polymer additive were weighed into a stirring container. After the additive was thoroughly dissolved, the filler shown in Table 1 as the dispersed phase was weighed and kneaded at 2000 rpm for 5 minutes using an Awatori Rentaro (Sinky Co., Ltd., model ARE-310). Next, the resin shown in Table 1 as the matrix was weighed and kneaded further at 2000 rpm for 5 minutes using the Awatori Rentaro to prepare the evaluation sample. The amounts used for crystalline polymer additives, fillers, resins as matrix, and solvents as matrix are as shown in the "Weight (g)" column of the table.

[0073] [Compatibility of crystalline polymer additives] The compatibility of the additives in the evaluation samples prepared as described above was confirmed according to the following criteria. Compatibility was evaluated at 25°C. Additive A is completely dissolved. At least a portion of additive B has not dissolved.

[0074] [Rheological properties (TI value)] One mL of the evaluation sample prepared as described above was used as the measurement sample. Using an Anton Paar MCR302 rotary rheometer and a PP20 parallel plate, measurements were taken at a temperature of 25°C and shear rates of 0.001 (1 / s) and 10 (1 / s). Specifically, a 20 mm diameter parallel plate PP20 (movable plate) was used, with a gap of 1 mm between it and the opposing plate (fixed plate). The temperature was set to 25°C, and the evaluation sample was placed in the gap. Viscosity (mPa·s) was measured under the conditions of shear rates of 0.001 (1 / s) and 10 (1 / s). The viscosity at a shear rate of 0.001 (1 / s) is given by η(0.001 sec). -1 ), the viscosity at a shear rate of 10 (1 / s) is η (10 sec -1 The ratio (TI value) was calculated as follows when ). TI value = η(0.001sec) -1 ) / η(10sec -1 ) Based on the TI value, the dispersibility and dispersion stability of the filler were evaluated according to the following criteria. A higher TI value indicates superior dispersibility and dispersion stability. S TI value is 1000 or higher A TI value between 250 and 1000 B TI value is between 100 and 250 CTI value is less than 100

[0075] <Example 2> In a reaction vessel fitted with a condenser, 1.2000 g of 1-pyrenylmethyl methacrylate, 10.9500 g of docosyl acrylate, 2.3013 g of polyethylene glycol methacrylate (Mn=360), 0.2237 g of 2-cyano-2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propane, 0.0403 g of 2,2'-azobis(isobutyronitrile), and 17.34 g of toluene were added and stirred. After purging the reaction vessel with nitrogen, the temperature of the reaction vessel was raised to 80 degrees Celsius while stirring, and the reaction was allowed to proceed for 17 hours. After that, the reaction vessel was cooled with ice to stop the reaction, and a copolymer solution was obtained. The obtained reaction solution was purified by adding it dropwise to methanol to obtain the copolymer (crystalline polymer additive) shown in formula (1). The number-average molecular weight of the obtained crystalline polymer additive was 18,400. The obtained crystalline polymer additive was evaluated in the same manner as in Example 1, and the results are shown in Table 1. The amounts of crystalline polymer additive, filler, matrix (resin), and matrix (solvent) used in each evaluation are as shown in Table 1.

[0076] <Example 3> In a reaction vessel fitted with a condenser, 1.2000 g of 1-pyrenylmethyl methacrylate, 4.1494 g of stearyl acrylate, 3.0734 g of dodecyl acrylate, 2.3013 g of polyethylene glycol methacrylate (Mn=360), 0.2154 g of 2-cyano-2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propane, 0.0321 g of 2,2'-azobis(isobutyronitrile), and 15.93 g of toluene were added and stirred. After purging the reaction vessel with nitrogen, the temperature of the reaction vessel was raised to 80 degrees Celsius while stirring, and the reaction was allowed to proceed for 17 hours. After that, the reaction vessel was cooled with ice to stop the reaction and obtain a copolymer solution. The obtained reaction solution was purified by adding it dropwise to methanol to obtain the copolymer (crystalline polymer additive) shown in formula (1). The number-average molecular weight of the obtained crystalline polymer additive was 13,800. The obtained crystalline polymer additive was evaluated in the same manner as in Example 1, and the results are shown in Table 1. The amounts of crystalline polymer additive, filler, matrix (resin), and matrix (solvent) used in each evaluation are as shown in Table 1.

[0077] <Example 4> In a reaction vessel fitted with a condenser, 5.0000 g of 1-pyrenylmethyl methacrylate, 2.1611 g of stearyl acrylate, 0.5993 g of polyethylene glycol methacrylate (Mn=360), 0.2158 g of 2-cyano-2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propane, 0.0276 g of 2,2'-azobis(isobutyronitrile), and 11.17 g of toluene were added and stirred. After purging the reaction vessel with nitrogen, the temperature of the reaction vessel was raised to 80 degrees Celsius while stirring, and the reaction was allowed to proceed for 17 hours. After that, the reaction vessel was cooled with ice to stop the reaction, and a copolymer solution was obtained. The obtained reaction solution was purified by adding it dropwise to methanol to obtain the copolymer (crystalline polymer additive) shown in formula (1). The number-average molecular weight of the obtained crystalline polymer additive was 8,100. The obtained crystalline polymer additive was evaluated in the same manner as in Example 1, and the results are shown in Table 1. The amounts of crystalline polymer additive, filler, matrix (resin), and matrix (solvent) used in each evaluation are as shown in Table 1.

[0078] <Example 5> In a reaction vessel fitted with a condenser, 1.2000 g of 1-pyrenylmethyl methacrylate, 9.3361 g of stearyl acrylate, 3.452 g of polyethylene glycol methacrylate (Mn=360), 0.2127 g of 2-cyano-2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propane, 0.0353 g of 2,2'-azobis(isobutyronitrile), and 18.71 g of toluene were added and stirred. After purging the reaction vessel with nitrogen, the temperature of the reaction vessel was raised to 80 degrees Celsius while stirring, and the reaction was allowed to proceed for 17 hours. After that, the reaction vessel was cooled with ice to stop the reaction, and a copolymer solution was obtained. The obtained reaction solution was purified by adding it dropwise to methanol to obtain the copolymer (crystalline polymer additive) shown in formula (1). The number-average molecular weight of the obtained crystalline polymer additive was 17,800. The obtained crystalline polymer additive was evaluated in the same manner as in Example 1, and the results are shown in Table 1. The amounts of crystalline polymer additive, filler, matrix (resin), and matrix (solvent) used in each evaluation are as shown in Table 1.

[0079] <Example 6> In a reaction vessel fitted with a condenser, 1.2500 g of 1-pyrenylmethyl methacrylate, 9.7252 g of stearyl acrylate, 3.3294 g of polyethylene glycol methyl ether methacrylate (Mn=500), 0.2250 g of 2-cyano-2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propane, 0.0330 g of 2,2'-azobis(isobutyronitrile), and 18.04 g of toluene were added and stirred. After purging the reaction vessel with nitrogen, the temperature of the reaction vessel was raised to 80 degrees Celsius while stirring, and the reaction was allowed to proceed for 17 hours. After that, the reaction vessel was cooled with ice to stop the reaction, and a copolymer solution was obtained. The obtained reaction solution was purified by adding it dropwise to methanol to obtain the copolymer (crystalline polymer additive) shown in formula (1). The number-average molecular weight of the obtained crystalline polymer additive was 17,500. The polyethylene glycol methyl ether methacrylate (Mn=500) used as a raw material is such that Y in monomer (b) described herein is an alkylene glycol chain represented by formula (3), and R 18 is an ethylene group, R 19 The group is a methyl group, and it is a monomer with 9 repeating groups. Polyethylene glycol methyl ether methacrylate (Mn=500) is indicated as EOME in the table. The obtained crystalline polymer additive was evaluated in the same manner as in Example 1, and the results are shown in Table 1. The amounts of crystalline polymer additive, filler, matrix (resin), and matrix (solvent) used in each evaluation are as shown in Table 1.

[0080] <Examples 7-9> In Examples 7 to 9, crystalline polymer additives were obtained using the same method as in Example 1. The types and amounts of crystalline polymer additives, fillers, matrix (resin), and matrix (solvent) used in each evaluation were as shown in Table 1, and the same evaluations as in Example 1 were performed. The results are shown in Table 1.

[0081] <Example 10> In a reaction vessel fitted with a condenser, 1.0000 g of 9-anthrylmethyl methacrylate, 8.4561 g of stearyl acrylate, 2.0844 g of polyethylene glycol methacrylate (Mn=360), 0.1976 g of 2-cyano-2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propane, 0.0307 g of 2,2'-azobis(isobutyronitrile), and 15.69 g of toluene were added and stirred. After purging the reaction vessel with nitrogen, the temperature of the reaction vessel was raised to 80 degrees Celsius while stirring, and the reaction was allowed to proceed for 17 hours. After that, the reaction vessel was cooled with ice to stop the reaction, and a copolymer solution was obtained. The obtained reaction solution was purified by adding it dropwise to methanol to obtain the copolymer (crystalline polymer additive) shown in formula (1). The number-average molecular weight of the obtained crystalline polymer additive was 16,300. The obtained crystalline polymer additive was evaluated in the same manner as in Example 1, and the results are shown in Table 1. The amounts of crystalline polymer additive, filler, matrix (resin), and matrix (solvent) used in each evaluation are as shown in Table 1.

[0082] <Comparative Example 1> In a reaction vessel fitted with a condenser, 0.3000 g of 1-pyrenylmethyl methacrylate, 8.6440 g of dodecyl acrylate, 2.8766 g of polyethylene glycol methacrylate (Mn=360), 0.2693 g of 2-cyano-2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propane, 0.0390 g of 2,2'-azobis(isobutyronitrile), and 19.92 g of toluene were added and stirred. After purging the reaction vessel with nitrogen, the temperature of the reaction vessel was raised to 80 degrees Celsius while stirring, and the reaction was allowed to proceed for 17 hours. After that, the reaction vessel was cooled with ice to stop the reaction, and a copolymer solution was obtained. The obtained reaction solution was purified by adding it dropwise to methanol to obtain a polymer additive. The number-average molecular weight of the obtained polymer additive was 13,400. The obtained polymer additives were evaluated in the same manner as in Example 1, and the results are shown in Table 1. The types and amounts of polymer additives, fillers, matrix (resin), and matrix (solvent) used in each evaluation are as described in Table 1.

[0083] <Comparative Example 2> In a reaction vessel fitted with a condenser, 12.0000 g of stearyl acrylate, 2.9579 g of polyethylene glycol methacrylate (Mn=360), 0.2804 g of 2-cyano-2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propane, 0.0436 g of 2,2'-azobis(isobutyronitrile), and 20.04 g of toluene were added and stirred. After purging the reaction vessel with nitrogen, the temperature of the reaction vessel was raised to 80 degrees Celsius while stirring, and the reaction was allowed to proceed for 17 hours. The reaction vessel was then cooled with ice to stop the reaction, and a copolymer solution was obtained. The obtained reaction solution was purified by adding it dropwise to methanol to obtain a polymer additive. The number-average molecular weight of the obtained polymer additive was 14,900. The obtained polymer additives were evaluated in the same manner as in Example 1, and the results are shown in Table 1. The types and amounts of polymer additives, fillers, matrix (resin), and matrix (solvent) used in each evaluation are as described in Table 1.

[0084] <Comparative Example 3> In a reaction vessel fitted with a condenser, 0.3500 g of 1-pyrenylmethyl methacrylate, 3.6116 g of methyl acrylate, 3.3561 g of polyethylene glycol methacrylate (Mn=360), 0.3142 g of 2-cyano-2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propane, 0.0432 g of 2,2'-azobis(isobutyronitrile), and 23.23 g of toluene were added and stirred. After purging the reaction vessel with nitrogen, the temperature of the reaction vessel was raised to 80 degrees Celsius while stirring, and the reaction was allowed to proceed for 17 hours. After that, the reaction vessel was cooled with ice to stop the reaction, and a polymer solution was obtained. The obtained reaction solution was purified by adding it dropwise to methanol to obtain a polymer additive. The number-average molecular weight of the obtained polymer additive was 7,800. The obtained polymer additives were evaluated in the same manner as in Example 1, and the results are shown in Table 1. The types and amounts of filler, matrix (resin), and matrix (solvent) used in each evaluation are as described in Table 1.

[0085] <Comparative Example 4> In a reaction vessel fitted with a condenser, 0.3200 g of 1-pyrenylmethyl methacrylate, 5.9922 g of hexyl acrylate, 3.0684 g of polyethylene glycol methacrylate (Mn=360), 0.2872 g of 2-cyano-2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propane, 0.0408 g of 2,2'-azobis(isobutyronitrile), and 21.24 g of toluene were added and stirred. After purging the reaction vessel with nitrogen, the temperature of the reaction vessel was raised to 80 degrees Celsius while stirring, and the reaction was allowed to proceed for 17 hours. After that, the reaction vessel was cooled with ice to stop the reaction, and a polymer solution was obtained. The obtained reaction solution was purified by adding it dropwise to methanol to obtain a polymer additive. The number-average molecular weight of the obtained polymer additive was 10,400. The obtained polymer additives were evaluated in the same manner as in Example 1, and the results are shown in Table 1. The types and amounts of filler, matrix (resin), and matrix (solvent) used in each evaluation are as described in Table 1.

[0086] <Comparative Example 5> In a reaction vessel fitted with a condenser, 5.0000 g of 1-pyrenylmethyl methacrylate, 0.1534 g of 2-cyano-2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propane, 0.0182 g of 2,2'-azobis(isobutyronitrile), and 7.46 g of toluene were added and stirred. After purging the reaction vessel with nitrogen, the temperature of the reaction vessel was raised to 80 degrees Celsius while stirring, and the reaction was allowed to proceed for 17 hours. The reaction vessel was then cooled with ice to stop the reaction, and a polymer solution was obtained. The obtained reaction solution was purified by adding it dropwise to methanol to obtain a polymer additive. The number-average molecular weight of the obtained polymer additive was 9,400. The obtained polymer additives were evaluated in the same manner as in Example 1, and the results are shown in Table 1. The types and amounts of filler, matrix (resin), and matrix (solvent) used in each evaluation are as described in Table 1.

[0087] <Comparative Example 6> The same evaluation as in Example 1 was performed, except that polymer additives were not used, and the results are shown in Table 1. The types and amounts of filler, matrix (resin), and matrix (solvent) used in each evaluation are as described in Table 1.

[0088] [Table 1]

[0089] The additives in each of Examples 1 to 10 are crystalline polymer additives having polycyclic aromatic rings and a melting point between 0°C and 100°C. The evaluation results of the filler-containing compositions containing the crystalline polymer additives, fillers, and matrices of Examples 1 to 10 showed high TI values, good dispersibility and dispersion stability of the fillers, and a balance of both physical properties. In contrast, Comparative Examples 1-5 are examples in which polymer additives were used that did not have polycyclic aromatic rings, or if they did, had melting points below 0°C or above 100°C, while Comparative Example 6 is an example in which no polymer additives were used. In all of the comparative examples, the TI values ​​were low, and both the dispersibility and dispersion stability of the filler were not achieved.

Claims

1. A crystalline polymer additive having polycyclic aromatic rings in its molecule and a melting point between 0°C and 100°C.

2. The crystalline polymer additive according to claim 1, which is an ester, an ether, an amide, or a siloxane.

3. A crystalline polymer additive according to claim 1 or 2, having a (meth)acrylate skeleton or a siloxane skeleton.

4. The crystalline polymer additive according to claim 1 or 2, which is a copolymer represented by the following formula (1) or a polysiloxane compound represented by the following formula (2). 【Chemistry 1】 The copolymer represented by formula (1) has a long-chain alkyl group-containing unit represented by (1a), a hydrophilic group-containing unit represented by (1b), and a polycyclic aromatic ring-containing unit represented by (1c), R １ ~R ３ Each of the following is independently a hydrogen atom or a methyl group, X is an alkyl group having 14 to 22 carbon atoms, Y is a polyalkylene glycol chain, Z is an atomic group containing a polycyclic aromatic ring, m is 1 to 200, n is 1 to 50, and l is 1 to 30. 【Chemistry 2】 In equation (2), R ４ ~R １５ Each of these is independently a methyl group, an atomic group containing 14 or more carbon atoms, or an atomic group containing a polycyclic aromatic ring. ４ ~R １５ In this configuration, at least one atom group contains 14 or more carbon atoms, and at least one atom group contains a polycyclic aromatic ring. j is between 1 and 100, k is between 1 and 20, and i is between 1 and 20.

5. A crystalline polymer additive according to claim 1 or 2, wherein the number average molecular weight is 4,000 or more and 100,000 or less.

6. The crystalline polymer additive according to claim 1 or 2, wherein the polycyclic aromatic ring has a fused ring structure in which four or more aromatic rings are fused together.

7. A crystalline polymer additive according to claim 1 or 2, having a maximum fluorescence peak in the range of 370 nm to 410 nm.

8. The crystalline polymer additive according to claim 1 or 2, having two maximum UV absorption peaks in the range of 320 nm to 350 nm.

9. A filler-containing composition comprising a crystalline polymer additive according to claim 1 or 2, a filler, and a matrix which is at least one of a resin or a solvent.

10. The filler-containing composition according to claim 9, wherein the filler is a thermally conductive filler.

11. The filler-containing composition according to claim 9, wherein the resin comprises a curable resin, and the curable resin comprises an epoxy compound.

Images