polymer additives

Abstract

The polymer additive of the present invention has an aromatic ring at the side chain or end of the polymer main chain, and also has at least one reactive functional group in its molecular structure, has a maximum fluorescence peak in the range of 370 nm or more and 410 nm or less, and has a total Hansen solubility parameter δtot represented by the following formula of 17 or more and 24 or less. (In the above formula, δd, δp, and δh represent the dispersion term, polarity term, and hydrogen bonding term of the Hansen solubility parameter, respectively.) According to the present invention, a polymer additive can be provided that has high solubility in medium to high polarity solvents, epoxy resins, acrylic resins, urethane resins, etc., and can also improve the dispersibility of π-conjugated fillers in these solvents or resins.

Description

Technology Field

[0001] The present invention relates to a polymer additive. Background Technology

[0002] Recently, as the amount of heat generated by electronic devices increases due to the high integration of circuits, thermal countermeasures have become critical, leading to a rising demand for heat dissipation materials. Heat dissipation materials are generally formed from resin compositions containing resin and fillers.

[0003] Boron nitride, graphite, carbon black, etc., are known as fillers having a six-membered ring structure and a π-electron conjugation system (hereinafter referred to as π-conjugated fillers), and are utilized for various purposes as inks or resin composites.

[0004] However, since π-conjugated fillers have low affinity for solvents or resins, it is common to use additives to improve affinity. In particular, polymer additives are commonly used to increase the dispersibility of fillers.

[0005] Polymer additives generally consist of a polymer main chain and a functional group that interacts with the filler (hereinafter sometimes referred to as a filler linker). Patent Document 1 describes an invention regarding a filler dispersant using an acrylic polymer. The dispersant described in Patent Document 1 has an ionic functional group as a filler linker. A dispersant having an ionic functional group (amine, carboxylic acid, phosphoric acid, etc.) exhibits a dispersion effect by binding to a functional group present on the side, edge, or other surface of the filler. However, for π-conjugated fillers having a surface without a functional group, such as the (001) surface of boron nitride, the reactivity is low and the filler dispersion effect is insufficient.

[0006] Meanwhile, using a polymer additive having an aromatic ring to increase the dispersibility of π-conjugated fillers through π-π interactions is also being considered.

[0007] Patent Document 2 describes an invention relating to a nano carbon dispersant having a specific repeating unit, and discloses a nano carbon dispersant having an atomic group in its structure that interacts with nano carbon and is adsorbable to the surface thereof. Furthermore, 1-pyrenyl groups, etc. are exemplified as functional groups.

[0008] Patent document 3 discloses a norbornene-based ring-opening (co)polymer having a maximum absorption wavelength of 300 nm to 400 nm, and specifically, a polymer having anthracene or pyrene is exemplified.

[0009] Patent document 4 discloses an invention regarding a method for dispersing pseudo-graphite nanoparticles using a dispersion aid based on a block copolymer, and exemplifies a compound having pyrene as a dispersion aid.

[0010] Patent document 5 discloses an invention relating to a conjugated polymer composed of specific repeating units, having a weight average molecular weight of 20,000 or more and a dispersion (Mw / Mn) of 2.40 or less, and the conjugated polymer may have, as substituents, a benzene ring, a naphthalene ring, anthracene ring, a phenanthrene ring, a perylene ring, a tetracene ring, a pyrene ring, etc.

[0011] Patent Document 6 discloses an invention relating to a nano-filler dispersant composition comprising (a) a reaction product of at least one halogenated copolymer and at least one polycyclic aromatic hydrocarbon comprising a unit derived from an isoolefin and para-alkylstyrene having 4 to 7 carbons, and (b) at least one nano-filler, wherein anthracene, pyrene, benzopyrene, etc. are described as polycyclic aromatic hydrocarbons. Prior art literature

[0012] Japanese Patent No. 6965703, Japanese Patent Publication No. 2012-82120, Japanese Patent Publication No. 2009-46615, Japanese Patent Publication No. 2012-520224, Japanese Patent Publication No. 2014-218669, Japanese Patent Publication No. 2018-537548 The problem to be solved

[0013] However, conventional polymer additives have low solubility in medium to high polarity solvents (e.g., toluene, 2-propanol, methyl ethyl ketone, etc.) and resins (e.g., various monomers for forming epoxy resins, acrylic resins, urethane resins, etc.), which sometimes resulted in precipitation. In addition, conventional additives had difficulty improving the dispersibility of π-conjugated fillers in the solvents or resins, leaving room for improvement.

[0014] Accordingly, the present invention aims to provide a polymer additive that has high solubility in medium to high polarity solvents or resins such as epoxy resins, and is capable of improving the dispersibility of π-conjugated fillers in these solvents. means of solving the problem

[0015] As a result of careful examination, the inventors have found that the product has an aromatic ring and at least one reactive functional group, and the maximum fluorescence peak is within the range of 370 nm to 410 nm, with a total Hansen solubility parameter δ tot The present invention was completed by discovering that the above problem can be solved by a polymer additive having a value of 17 or more and 24 or less.

[0016] That is, the present invention relates to the following [1] to

[12] .

[0017] [1] Having an aromatic ring on a side chain or terminal of the polymer main chain, and also having at least one reactive functional group in the molecular structure, with a maximum fluorescence peak in the range of 370 nm to 410 nm, and a total Hansen solubility parameter δ represented by the following formulatot A polymer additive having a value of 17 or more and 24 or less.

[0018] [Mathematical Formula 1]

[0019]

[0020] (δ in the above formula d , δ p , δ h )

[0021] [2] Polar term δ of the above Hansen solubility parameter p A polymer additive described in [1] above, having a value of 0.5 or more and 19 or less.

[0022] [3] The above-described polymer additive described in [1] or [2] comprises a condensed ring compound in which four or more six-membered rings are condensed.

[0023] [4] A polymer additive described in [3], wherein the number of the above condensed ring compounds is 1 or more and 5 or less per polymer chain.

[0024] [5] A polymer additive described in any one of [1] to [4], wherein the reactive functional group comprises one selected from the group consisting of a hydroxyl group, an acid anhydride group, and a trialkoxysilyl group.

[0025] [6] A polymer additive described in any one of [1] to [5], having a number average molecular weight (Mn) measured by GPC of 4,000 or more and 100,000 or less.

[0026] [7] A polymer additive described in any one of [1] to [6] having two maximum peaks of UV absorption within a range of 320 nm or more and 350 nm or less.

[0027] [8] A polymer additive described in any one of [1] to [7], wherein the polymer main chain comprises (meth)acrylate.

[0028] [9] A polymer additive described in any one of [1] to [8] having an alkyl group having 1 to 22 carbon atoms in its molecular structure.

[0029]

[10] A filler-containing composition comprising a polymer additive described in any one of [1] to [9] above, a filler, and a matrix which is at least one of a resin or a solvent.

[0030]

[11] A filler-containing composition as described in

[10] , wherein the filler is a thermally conductive filler.

[0031]

[12] A filler-containing composition as described in

[10] or

[11] , wherein the resin comprises a curable resin and the curable resin comprises an epoxy compound. Effects of the invention

[0032] It is possible to provide a polymer additive that has high solubility in medium to high polarity solvents, epoxy resins, etc., and also improves the dispersibility of π-conjugated fillers in these solvents. Specific details for implementing the invention

[0033] [Polymer Additives]

[0034] The polymer additive of the present invention has an aromatic ring at a side chain or terminal of the polymer main chain, and also has at least one reactive functional group in its molecular structure, has a maximum fluorescence peak within the range of 370 nm to 410 nm, and a total Hansen solubility parameter δ represented by the following formula. tot It is 17 or more and 24 or less.

[0035] [Mathematical Formula 2]

[0036]

[0037] (δ d , δ p , δ h ) represents the dispersion term, polarity term, and hydrogen bonding term of the Hansen solubility parameter, respectively.

[0038] The polymer additive of the present invention, by having the above composition, improves solubility in medium to high polarity solvents or solubility in resins. Furthermore, in this specification, solubility in resins refers to the compatibility between the polymer additive and the resin after curing, and if the compatibility of the polymer additive with the resin after curing is good, the solubility in the resin is considered good.

[0039] In addition, in the present invention, it is necessary to have excellent solubility in both medium-to-high polarity solvents and resins. By being soluble in both medium-to-high polarity solvents and resins, for example, it becomes easy to produce a slurry made of a composite material of resin and filler without impairing various physical properties after the resin is cured.

[0040] <Directional Circle>

[0041] The polymer additive of the present invention has an aromatic ring at the side chain or end of the polymer main chain. By having an aromatic ring, the polymer additive is more likely to form π-π interactions with the π-conjugated filler. Due to these π-π interactions between the polymer additive and the filler, the dispersibility of the filler is improved.

[0042] Here, the π-conjugated filler is a filler having a six-membered ring atomic structure as a constituent unit, such as boron nitride, graphite, and carbon black.

[0043] The aromatic ring of the polymer additive preferably comprises a condensed ring compound in which a plurality of aromatic rings (six-membered rings) are condensed. By including the condensed ring compound, the polymer additive facilitates π-π interactions with the π-conjugated filler, thereby making it easier to improve the dispersibility of the filler.

[0044] Examples of the above condensed ring compounds include naphthalene, anthracene, phenanthrene, triphenylene, pyrene, tetracene, picene, perylene, pentapene, pentacene, hexaphene, etc. Additionally, at least one of the hydrogen atoms constituting the condensed ring compound may be substituted with a substituent. Examples of substituents include organic groups having 1 to 10 carbon atoms.

[0045] Among these, from the perspective of improving the dispersibility of the π-conjugated filler, it is preferable that the condensed ring compound of the polymer additive be a condensed ring compound in which four or more six-membered rings are condensed. Furthermore, among the condensed ring compounds in which four or more six-membered rings are condensed, pyrene is particularly preferred from the perspective of improving the solubility of the polymer additive in medium to high polarity solvents.

[0046] In addition, it is preferable that the number of condensed ring compounds be one or more and five or fewer per polymer chain of the polymer additive. If the number of condensed ring compounds is one or more, they are more likely to interact with π-conjugated fillers, thereby improving dispersibility. In addition, if the number of condensed ring compounds is five or fewer, the polymer additive is less likely to self-aggregate, thereby improving solubility in solvents or resins.

[0047] The number of condensed ring compounds is more preferably 1 or more and 3 or fewer per polymer chain of the polymer additive, and more preferably 1.

[0048] <Reactive Functional Group>

[0049] The polymer additive of the present invention has at least one reactive functional group in its molecular structure. By having a reactive functional group, the polymer additive becomes more likely to react or interact with the resin, thereby improving solubility in the resin. The type of reactive functional group having the polymer additive is not particularly limited, and a reactive functional group that is easy to react or interact with the resin can be selected.

[0050] As for the reactive functional group, it is preferable to have one or more selected from the group consisting of trialkoxysilyl groups, vinyl groups, acid anhydride groups, carboxyl groups, amino groups, hydroxyl groups, isocyanate groups, urethane groups, oxazoline groups, oxetane groups, cyanate groups, phenol groups, hydrazide groups, and amide groups. Among these, it is preferable to have any one selected from the group consisting of hydroxyl groups, acid anhydride groups, and trialkoxysilyl groups, and among these, hydroxyl groups are more preferable. Furthermore, as for the trialkoxysilyl group, trimethoxysilyl groups are preferred.

[0051] <alkyl group>

[0052] The polymer additive of the present invention preferably has an alkyl group having 1 to 22 carbon atoms in its molecular structure. Regarding the alkyl group, an alkyl group having 6 to 18 carbon atoms is preferred, and an alkyl group having 8 to 18 carbon atoms is more preferred, from the perspective of adjusting the total Hansen solubility parameter described later to a desired range. Specifically, examples of the alkyl group include a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a pentadecyl group, an octadecyl group (stearyl group), etc. Among these, a dodecyl group and an octadecyl group (stearyl group) are preferred, and an octadecyl group (stearyl group) is more preferred.

[0053] <Structure of Polymer Additives>

[0054] The polymer main chain of the polymer additive of the present invention is not particularly limited, but preferably comprises (meth)acrylate. More specifically, the polymer additive of the present invention is preferably a polymer comprising constituent units derived from (meth)acrylate. In this specification, (meth)acrylate refers to acrylate or methacrylate, and other similar terms are used as well.

[0055] The polymer additive of the present invention is preferably a polymer represented by the following general formula (1), which is a polymer comprising a constituent unit derived from (meth)acrylate.

[0056]

[0057] In Formula (1), R1 is an alkyl group having 1 to 22 carbon atoms, R2 is a group containing a reactive functional group, and R3 is a group containing an aromatic ring. R4 to R6 are each independently hydrogen atoms or methyl groups. x represents the number of units having R1 (hereinafter referred to as alkyl group-containing units) and is 10 to 200. y represents the number of units having R2 (hereinafter referred to as reactive group-containing units) and is 5 to 50. z represents the number of units having R3 (hereinafter referred to as aromatic ring-containing units) and is 1 to 5. Also, * at both ends indicates a bond loss. * is usually bonded to a group (generally an organic group having 1 to 20 carbon atoms) derived from a reagent, such as a polymerization initiator, used in the manufacture of the polymer represented by Formula (1).

[0058] The polymer additive represented by formula (1) is composed of an alkyl group-containing unit, a reactive group-containing unit, and an aromatic ring-containing unit, and each unit may be bonded in a block or in a random manner.

[0059] Also, depending on the number of each unit, the Hansen solubility parameter δ tot It can be adjusted. For example, by reducing the number of alkyl group-containing units or increasing the number of reactive group-containing units, the total Hansen solubility parameter δ tot , polar term δ of the Hansen solubility parameter p The value of can be adjusted to a higher level.

[0060] R1 is preferably an alkyl group having 6 to 18 carbon atoms, and more preferably an alkyl group having 8 to 18 carbon atoms, from the perspective of adjusting the total Hansen solubility parameter described below to a desired range. Specifically, the alkyl group may include a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a pentadecyl group, an octadecyl group (stearyl group), etc. Among these, a dodecyl group and an octadecyl group (stearyl group) are preferred, and an octadecyl group (stearyl group) is more preferred.

[0061] R2 is a group containing a reactive functional group, and the reactive functional group is as described above. That is, the reactive functional group is preferably one or more selected from the group consisting of a trialkoxysilyl group, a vinyl group, an acid anhydride group, a carboxyl group, an amino group, a hydroxyl group, an isocyanate group, a urethane group, an oxazoline group, an oxetane group, a cyanate group, a phenol group, a hydrazide group, and an amide group. Among these, it is preferable to be any one selected from the group consisting of a hydroxyl group, an acid anhydride group, and a trialkoxysilyl group, and among these, a hydroxyl group is more preferable. Furthermore, among the trialkoxysilyl groups, a trimethoxysilyl group is preferred.

[0062] R3 is a group containing an aromatic ring. The aromatic ring is preferably a condensed ring compound, and examples of condensed ring compounds include naphthalene, anthracene, phenanthrene, triphenylene, pyrene, tetracene, phycene, perylene, pentapene, pentacene, hexaphene, etc., among which pyrene is preferred.

[0063] In formula (1), x is 10 or more and 200 or less, preferably 20 or more and 100 or less, and more preferably 30 or more and 60 or less.

[0064] In formula (1), y is 5 or more and 50 or less, preferably 6 or more and 30 or less, and more preferably 8 or more and 15 or less.

[0065] In formula (1), z is 1 or more and 5 or less, preferably 1 or more and 3 or less, and more preferably 1.

[0066] By setting x, y, and z to the above ranges, the total Hansen solubility parameter δ described below tot , polar term δ of the Hansen solubility parameter p It becomes easier to adjust to the desired range.

[0067] The polymer additive of the present invention is a polymer represented by formula (2) more preferably in order to improve solubility in medium to high polarity solvents and resins, and further improve the dispersibility of π-conjugated fillers in these solvents and resins.

[0068]

[0069] The polymer additive represented by Equation (2) is such that R2 in Equation (1) is "-(R7-O) n Except for the fact that it is "-H" and that R3 in Equation (1) is "-CH2-R8", it is the same as Equation (1). That is, R1, R4~R6, x, y, and z are identical to Equation (1).

[0070] R7 is an alkylene group having 2 to 4 carbon atoms, preferably an ethylene group. Also, n represents the number of repetitions of the oxyalkylene group (R7-O), which is 1 to 50, preferably 3 to 20, and more preferably 6 to 12.

[0071] R8 is a condensed ring compound, and examples include naphthalene, anthracene, phenanthrene, triphenylene, pyrene, tetracene, phycene, perylene, pentapene, pentacene, hexaphene, etc., among which pyrene is preferred.

[0072] The polymer additive of the present invention is a polymer represented by formula (3) more preferably in order to improve solubility in medium to high polarity solvents and resins, and further improve the dispersibility of π-conjugated fillers in these solvents and resins.

[0073]

[0074] The polymer additive represented by Equation (3) is a polymer additive in which R4 to R6 in Equation (2) are methyl groups, R7 is an ethylene group, and R8 is pyrene. R1, x, y, and z are the same as in Equation (1).

[0075] The polymer additives represented by the above formulas (1) to (4) can be obtained by polymerizing the following monomers (a) to (c) to form an alkyl group-containing unit, a reactive group-containing unit, and an aromatic ring-containing unit.

[0076]

[0077] R1 to R6 in the monomers of (a) to (c) above are identical to those described in Equation (1) above.

[0078] The polymerization method can utilize a general method for polymerizing acrylic monomers, but it is preferable to apply RAFT polymerization (Reversible Addition-Fragmentation Chain Transfer Polymerization) to improve solubility in solvents and dispersibility of fillers by appropriately adjusting the molecular weight of the polymer additive.

[0079] When RAFT polymerization is applied, the structure derived from the polymerization initiator and RAFT reagent (chain transfer agent) used in RAFT polymerization becomes the end of the polymer additive. That is, * in Formula (1) is preferably combined with the structure derived from the polymerization initiator and RAFT reagent (chain transfer agent) used in RAFT polymerization. In this case, an example of the specific structure of the polymer additive is as follows.

[0080]

[0081] In Equation (4), R1 is as described in Equation (1), and n is as described in Equation (3).

[0082] <Maximum Fluorescence Peak>

[0083] The polymer additive of the present invention has a maximum fluorescence peak within the range of 370 nm to 410 nm. As the maximum fluorescence peak is within the above range, it becomes easier to interact with π-conjugated fillers, and also makes it easier to suppress the stacking of aromatic rings, such as condensed ring compounds. As a result, the solubility and dispersibility of the polymer additive in solvents or resins are improved.

[0084] The maximum fluorescence peak is preferably 380 nm or more and 410 nm or less, more preferably 390 nm or more and 410 nm or less, and even more preferably within the range of 395 nm or more and 405 nm or less.

[0085] The maximum fluorescence peak can be adjusted depending on the type of aromatic ring in the polymer additive.

[0086] In addition, the maximum fluorescence peak can be measured by the method described in the example.

[0087] <Hansen Solubility Parameter>

[0088] The polymer additive of the present invention has a total Hansen solubility parameter δ represented by the following formula. tot It is 17 or more and 24 or less.

[0089] [Mathematical Formula 3]

[0090]

[0091] (δ d , δ p , δ h ) represents the dispersion term, polarity term, and hydrogen bonding term of the Hansen solubility parameter, respectively.

[0092] Total Hansen solubility parameter δ tot is the root mean square of the three parameters of the Hansen solubility parameter (HSP): the dispersion term, the polarity term, and the hydrogen bonding term.

[0093] Total Hansen solubility parameter δ of polymer additives totIf δ is 17 or higher and 24 or lower, solubility in medium to high polarity solvents is improved. The Hansen solubility parameter δ is preferably 17 or higher and 22 or lower, and more preferably 18 or higher and 20 or lower.

[0094] Also, the polar term δ of the Hansen solubility parameter p In terms of increasing the solubility of the polymer additive in medium to high polarity solvents, it is preferably 0.5 or more and 19 or less, more preferably 1 or more and 10 or less, and even more preferably 2 or more and 6 or less.

[0095] While the Hildebrand solubility parameter, generally known as the SP value (δ), assumes that the forces acting between the solvent and solute are solely intermolecular forces, the Hansen solubility parameter (HSP) represents solubility, and the dispersion term δ d , polar term δ p , hydrogen bonding term δ h It is represented in three-dimensional space. Variance term δ d is the effect due to dispersion forces, polar term δ p is the effect due to inter-dipole forces, hydrogen bonding term δ h This indicates the effect caused by hydrogen bonding.

[0096] The definition and calculation of Hansen solubility parameters are described in Charles M. Hansen’s *Hansen Solubility Parameters: A Users Handbook* (CRC Press, 2007). Additionally, Hansen solubility parameters can be easily estimated using the computer software *Hansen Solubility Parameters in Practice* (HSPiP).

[0097] Total Hansen solubility parameter δ of polymer additives tot The above formula is expressed by the above formula and is obtained by performing a test to measure solubility using a solvent in which the Hansen solubility parameter (HSP) is already known. The details are as described in the examples.

[0098] <Molecular Weight>

[0099] The number average molecular weight of the polymer additive of the present invention is not particularly limited, but is preferably 4,000 or more and 100,000 or less. If the number average molecular weight of the polymer additive is 4,000 or more, it becomes easier to improve the dispersibility of the filler. In addition, if the number average molecular weight of the polymer additive is 100,000 or less, solubility in medium to high polarity solvents, epoxy resins, etc. is improved.

[0100] The number average molecular weight of the polymer additive is more preferably 6,000 or more and 30,000 or less, and more preferably 8,000 or more and 15,000 or less.

[0101] The number average molecular weight of the polymer additive can be measured by gel permeation chromatography (GPC) and is a value equivalent to standard polystyrene.

[0102] <Ultraviolet Absorption (UV)>

[0103] The polymer additive of the present invention preferably has two maximum peaks of UV absorption in the range of 320 nm to 350 nm when measuring the ultraviolet absorption (UV) spectrum. A polymer additive having two maximum peaks of UV absorption in such a specific wavelength range is easy to improve the dispersibility of π-conjugated fillers and is also easy to increase solubility in medium to high polarity solvents.

[0104] The ultraviolet absorption spectrum of a polymer additive can be adjusted according to the type of aromatic ring, such as a condensation aromatic ring, possessed by the polymer additive.

[0105] <Uses>

[0106] The polymer additive of the present invention can be suitably used as a dispersant for various fillers.

[0107] As for the filler, it is not particularly limited, but from the perspective of use as a heat dissipation material, it is preferable to have a thermally conductive filler, and examples include aluminum, copper, nickel, aluminum oxide (alumina), magnesium oxide, zinc oxide, aluminum hydroxide, aluminum nitride, diamond, boron nitride, carbon-based materials, etc.

[0108] Here, a thermally conductive filler is a filler having thermal conductivity, preferably a filler having a thermal conductivity of 10 W / m·K or higher. As described above, the polymer additive of the present invention can effectively disperse π-conjugated fillers. Therefore, the polymer additive of the present invention can be suitably used as a dispersant for π-conjugated fillers such as boron nitride and carbon-based materials. Examples of boron nitride include boron nitride nanotubes, boron nitride nanosheets, hexagonal boron nitride particles, etc. Examples of carbon-based materials include graphite, carbon black, carbon fiber, carbon nanotubes, etc.

[0109] The average particle size of the filler is not particularly limited, but, for example, 1 to 100 μm, preferably 1 to 50 μm, and more preferably 1 to 10 μm. In addition, the average particle size refers to the particle size (D50) at a volume integration of 50% in the particle size distribution of insulating fine particles obtained by laser diffraction and scattering.

[0110] When the polymer additive of the present invention is used as a dispersant for a filler, the amount of the polymer additive per 100 parts by mass of the filler may be, for example, 0.5 to 10 parts by mass, more preferably 1 to 5 parts by mass.

[0111] The polymer additive of the present invention has good solubility in medium to high polarity solvents. Therefore, it can be suitably used for applications in which fillers are dispersed in medium to high polarity solvents.

[0112] Medium to high polarity solvents include, for example, toluene, ethyl acetate, methyl ethyl ketone, tetrahydrofuran, acetone, cyclohexanone, n-propanol, 2-propanol, ethanol, methanol, etc.

[0113] The polymer additive of the present invention may also be used for dispersing fillers in a resin (matrix). Examples of resins include curable resins, thermoplastic resins, elastomer resins, etc. Examples of curable resins include epoxy resins, silicone resins, urethane resins, phenolic resins, unsaturated polyester resins, polyimide resins, oxetane resins, etc.

[0114] In addition, 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, polyvinyl chloride resin (PVC), etc.

[0115] Among the resins mentioned above, it is preferable to include a curable resin. Furthermore, it is preferable that the curable resin includes an epoxy resin. It is preferable that the epoxy resin contains an epoxy compound and a curing agent.

[0116] Examples of epoxy compounds include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol S type epoxy compounds, phenol novolak type epoxy compounds, biphenyl type epoxy compounds, biphenyl novolak type epoxy compounds, biphenol type epoxy compounds, naphthalene type epoxy compounds, fluorene type epoxy compounds, phenol aralyl type epoxy compounds, naphthol aralyl type epoxy compounds, dicyclopentadiene type epoxy compounds, anthracene type epoxy compounds, epoxy compounds having an adamantane backbone, epoxy compounds having a tricyclodecane backbone, naphthylene ether type epoxy compounds, and epoxy compounds having a triazine nucleus backbone.

[0117] Examples of curing agents include phenol compounds (phenol curing agents), amine compounds (amine curing agents), imidazole compounds, acid anhydrides, cyanate ester compounds, carbodiimide compounds, imide oligomers, etc.

[0118] An imide oligomer is a compound having an imide skeleton in its main chain, and preferably a compound having an aromatic ring in its skeleton.

[0119] The imide oligomer has a reactive functional group capable of reacting with the curable resin at both ends or one end of the molecule, 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 any one of a primary amino group, a secondary amino group, and a tertiary amino group. The hydroxyl group may be a phenolic hydroxyl group or a hydroxyl group other than a phenolic hydroxyl group.

[0120] In addition, elastomer resins include acrylonitrile butadiene rubber, ethylene propylene diene rubber, ethylene-propylene rubber, natural rubber, polybutadiene rubber, polyisoprene rubber, etc. These elastomer resins may be liquid elastomers that become liquid at room temperature (23°C) and atmospheric pressure (1 atm), solid elastomers, or mixtures thereof.

[0121] In addition, as elastomer resins, thermoplastic elastomers such as polyester-based thermoplastic elastomers, polyurethane-based thermoplastic elastomers, and styrene-based thermoplastic elastomers can also be used.

[0122] The polymer additive of the present invention has high solubility for monomers for forming resins such as epoxy resin. In addition, the polymer additive of the present invention has reactive functional groups, so it reacts easily with resins such as epoxy resin and can disperse fillers in the resin with good dispersibility.

[0123] For example, when a monomer for forming a resin such as an epoxy resin, a filler, and the polymer additive of the present invention are mixed in a medium to high polarity solvent, the solubility of the polymer additive in the monomer is good, and the dispersibility of the filler in the solvent becomes better. Therefore, when a polymer is formed by polymerizing the monomer in the solvent, a filler / polymer composite with good dispersibility of the filler can be obtained. In particular, even when a π-conjugated filler is used as the filler, if the polymer additive of the present invention is used, a π-conjugated filler / polymer composite with good dispersibility of the π-conjugated filler can be produced. Since the dispersibility of the filler is excellent, these filler / polymer composites have uniform physical properties such as thermal conductivity and excellent relaxation of the interfacial modulus.

[0124] <Resin Composition>

[0125] In the present invention, a resin composition comprising the above-described polymer additive, a filler, and a matrix which is at least one of a resin or a solvent may be provided. Furthermore, specific examples of the resin, solvent, and filler are as described above.

[0126] Examples

[0127] The present invention is clarified below by providing specific embodiments and comparative examples of the present invention. Furthermore, the present invention is not limited to the following embodiments.

[0128] [Molecular weight]

[0129] The number average molecular weight of each polymer additive was measured under the following conditions.

[0130] Measurements were performed using a Waters "ACQUITY APC System" as the GPC device, an LF-604 6.0×150 mm column, and THF as the solvent, at a flow rate of 0.3 mL / min and a temperature of 40°C. Polystyrene specimens were used as standard samples.

[0131] [Maximum Fluorescence Peak]

[0132] The fluorescence spectrum of each polymer additive was measured. Specifically, using a “Spectrofluorescence Photometer F-2700” manufactured by Hitachi High-Tech Science, the fluorescence spectrum was obtained by measuring each polymer additive between slide glasses to a thickness of 40 μm under conditions of an excitation wavelength of 339 nm, and the wavelength at which the intensity in the fluorescence spectrum was maximum was set as the maximum fluorescence peak.

[0133] [Maximum peak of ultraviolet (UV) absorption]

[0134] The UV absorption peaks of each polymer additive were measured using a "U-3900 Spectrophotometer" manufactured by Hitachi High-Tech Science Co., Ltd.

[0135] [Total Hansen solubility parameter δ tot ]

[0136] Each polymer additive was dissolved in 25 types of solvents selected from the Master database in which the Hansen solubility parameter (HSP) was confirmed, and the solubility and dispersibility were evaluated.

[0137] The 25 types of solvents used and the Hansen solubility parameters (HSP) are as shown in Table 1.

[0138] Also, the variance term δ d , polar term δ p , and hydrogen bonding term δ h The unit is "MPa 1 / 2"am.

[0139]

[0140] (Evaluation of Solubility and Dispersibility)

[0141] The solubility and dispersibility of each polymer additive were determined as follows.

[0142] Each polymer additive was added to each of the solvents shown in Table 1 to a concentration of 5 mass%, and stirred at room temperature (25°C) for 30 minutes at 50 rpm using a mix rotor manufactured by Ez One Co., Ltd., product number VMR-5R. After stirring, the mixture was left to stand at room temperature (25°C) for 1 hour, and the solubility and dispersibility were evaluated according to the following criteria.

[0143] Score 1: No dissolution or precipitation

[0144] Score 2: Dissolution · Slight Precipitation

[0145] Score 3: Dissolution · More than half precipitated

[0146] Score 4: Dissolution · Near Precipitation

[0147] Score 5: Insoluble · Completely precipitated

[0148] For each solvent shown in Table 1, after determining the score, the HSP was estimated using the computer software Hansen Solubility Parameters in Practice (HSPiP).

[0149] Specifically, the HSPiP Sphere program was launched, and each solvent used for the evaluation of solubility and dispersibility was selected on the program. Next, the score of each solvent specified by the above method was input into the program, and by executing the calculation, δ tot , δ p It automatically calculated.

[0150] <Dispersion Assessment>

[0151] A polymer additive solution was prepared by adding 0.2g of the polymer additive of each example and comparative example to 20g of methyl ethyl ketone and stirring. To the polymer additive solution, 0.2g of boron nitride (UHP-1K manufactured by Showa Kenko Co., Ltd., flaky, average particle size 8μm) was added as a filler, and the mixture was stirred for 5 minutes at a stirring speed of 100rpm using a self-rotating ultrasonic nano disperser "PR-1" (Shinkie Co.). Afterward, the mixture was left to stand for 5 minutes and mixed by hand to obtain a dispersion. The obtained dispersion was transferred to a centrifuge tube (Biolamo, product number VIO-50BN), and the thickness of the precipitate was measured after 10 minutes of standing and evaluated according to the following criteria.

[0152] (metewand)

[0153] A: Precipitate thickness is 8 mm or less

[0154] B: Precipitate thickness exceeds 8 mm and is 9.5 mm or less

[0155] C: Precipitate thickness exceeds 9.5 mm

[0156] <Solubility Evaluation>

[0157] Evaluation of solubility in 2-propanol

[0158] 0.4 g of the polymer additive of each example and comparative example was added to 8 g of 2-propanol and stirred to confirm the solubility of the polymer additive. Specifically, the transmission spectrum of the polymer additive solution was obtained using a "Spectrophotometer U-3900" manufactured by Hitachi High-Tech Science Co., Ltd., and the transmittance at a wavelength of 600 nm was measured. The solubility evaluation was performed at 25°C and evaluated according to the following criteria.

[0159] (metewand)

[0160] A: Transmittance of 90% or more

[0161] B: Transmittance of 50% or more and less than 90%

[0162] C: Transmittance less than 50%

[0163] Solubility evaluation of epoxy resin

[0164] A reaction solution was obtained by stirring and mixing 0.2g of the polymer additive of each example and comparative example, 1.0g of bisphenol A type epoxy resin (YD-127, manufactured by Nittetsu Chemical & Material Co.), 0.010g of an imidazole type curing accelerator (manufactured by Shikoku Kasei Co.), and 1.2g of methyl ethyl ketone. Subsequently, 0.3g of the solution was dropped onto a slide glass, formed into a 140μm thick sheet, and dried at 100°C for 10 minutes. After drying, the sheet was placed between slide glasses from above and cured at 150°C for 30 minutes and at 200°C for 90 minutes to evaluate the solubility of the polymer additive in the epoxy resin. Specifically, the total light transmittance of the polymer additive solution was measured using a "Spectrochromatic Color Haze Meter COH 7700" manufactured by Japan Zenk Kogyo Co., Ltd. and evaluated according to the following criteria.

[0165] (metewand)

[0166] A: Total light transmittance of 80% or more

[0167] B: Total light transmittance 70% or more and less than 80%

[0168] C: Total light transmittance less than 70%

[0169] <Example 1>

[0170] 0.3158 g of 1-pyrenylmethyl methacrylate, 11.5324 g of dodecyl methacrylate, 3.6446 g of polyethylene glycol methacrylate (Mn=360), 0.1717 g of 2-cyanopropane-2-yl benzodithioic acid, 0.0317 g of 2,2'-azobis(isobutyronitrile), and 19.70 g of toluene were added to a reaction vessel equipped with a cooling tube and stirred. After purging the reaction vessel with nitrogen, the temperature of the reaction vessel was raised to 80 degrees while stirring, and the reaction was carried out for 17 hours. Afterward, the reaction vessel was cooled to ice to stop the reaction, and a copolymer solution was obtained. The obtained reaction solution was purified by adding it dropwise to methanol, thereby obtaining a polymer additive represented by Equation (5). The number average molecular weight of the obtained polymer additive was 15,360. The structure of the obtained polymer additive is as shown in Table 3. In addition, 1 The progression of the above reaction was confirmed by H NMR measurement. Using a JEOL "ECX-400" as the NMR measuring device, measurements were performed with chloroform as the solvent under the conditions of a sample concentration of 1 wt%, 25°C, a measurement frequency of 400 MHz, and an integration count of 8 times. Similarly, for other examples and comparative examples, the progression of the reaction 1 Confirmed by H NMR measurement.

[0171]

[0172] <Example 2>

[0173] In Example 1, a polymer additive of Formula (7) was obtained in the same manner as in Example 1, except that the compound of Formula (6) below was used instead of 1-pyrenylmethyl methacrylate, benzodithioic acid 2-cyanopropane-2-yl was not used, and the amount of each component was adjusted according to Table 2. The details of the obtained polymer additive are as shown in Table 3.

[0174]

[0175]

[0176] <Example 3>

[0177] A polymer additive of Formula (8) was obtained by making the same as Example 1, except that the amount of each component was adjusted according to Table 2. The details of the obtained polymer additive are as shown in Table 3.

[0178]

[0179] <Example 4>

[0180] In Example 1, propyl methacrylate was used instead of dodecyl methacrylate, and the amount of each component was adjusted according to Table 2, except that the procedure was the same as in Example 1 to obtain the polymer additive of Formula (9). The details of the obtained polymer additive are as shown in Table 3.

[0181]

[0182] <Example 5>

[0183] A polymer additive of Formula (10) was obtained by making the same as Example 1, except that the amount of each component was adjusted according to Table 2. The details of the obtained polymer additive are as shown in Table 3.

[0184]

[0185] <Example 6>

[0186] A polymer additive of Formula (11) was obtained by making the same as Example 1, except that the amount of each component was adjusted according to Table 2. The details of the obtained polymer additive are as shown in Table 3.

[0187]

[0188] <Example 7>

[0189] A polymer additive of Formula (12) was obtained by making the same as Example 1, except that the amount of each component was adjusted according to Table 2. The details of the obtained polymer additive are as shown in Table 3.

[0190]

[0191] <Example 8>

[0192] In Example 1, a polymer additive of Formula (20) was obtained in the same manner as in Example 1, except that stearyl acrylate was used instead of dodecyl methacrylate and 2-(methacryloyloxy)ethyl 1,3-dioxo-1,3-dihydroisobenzofuran-5-carboxylate was used instead of polyethylene glycol methacrylate, and the amount of each component was adjusted according to Table 2. The details of the obtained polymer additive are as shown in Table 3.

[0193]

[0194] <Example 9>

[0195] In Example 8, 3-(trimethoxysilyl)propyl methacrylate was used instead of 2-(methacryloyloxy)ethyl-1,3-dioxo-1,3-dihydroisobenzofuran-5-carboxylate, and polyethylene glycol methacrylate was used, and the amount of each component was adjusted according to Table 2. Except for these differences, the polymer additive of Formula (21) was obtained in the same manner as in Example 8. The details of the obtained polymer additive are as shown in Table 3.

[0196]

[0197] In Equation (21), y1=5 and y2=8. That is, the total number of units containing reactive groups is 13.

[0198] <Example 10>

[0199] In Example 9, the polymer additive of Formula (22) was obtained in the same manner as in Example 9, except that 3-(trimethoxysilyl)propyl methacrylate was not used and the amount of each component was adjusted according to Table 2. The details of the obtained polymer additive are as shown in Table 3.

[0200]

[0201] <Comparative Example 1>

[0202] In Example 1, the polymer additive of Formula (13) was obtained in the same manner as in Example 1, except that 1-pyrenylmethyl methacrylate was not used and the amount of each component was adjusted according to Table 2. The details of the obtained polymer additive are as shown in Table 3.

[0203]

[0204] <Comparative Example 2>

[0205] In Example 1, 9-anthylmethyl methacrylate was used instead of 1-pyrenylmethyl methacrylate, and the amount of each component was adjusted according to Table 2, except that the procedure was the same as in Example 1 to obtain the polymer additive of Formula (14). The details of the obtained polymer additive are as shown in Table 3.

[0206]

[0207] <Comparative Example 3>

[0208] In Example 1, benzyl methacrylate was used instead of 1-pyrenylmethyl methacrylate, and the amount of each component was adjusted according to Table 2, except that the procedure was the same as in Example 1 to obtain the polymer additive of Formula (15). The details of the obtained polymer additive are as shown in Table 3.

[0209]

[0210] <Comparative Example 4>

[0211] A polymer additive of Formula (16) was obtained by making the same as Example 1, except that the amount of each component was adjusted according to Table 2. The details of the obtained polymer additive are as shown in Table 3.

[0212]

[0213] <Comparative Example 5>

[0214] In Example 1, ethyl methacrylate was used instead of dodecyl methacrylate, and the amount of each component was adjusted according to Table 2, except that the procedure was the same as in Example 1 to obtain the polymer additive of Formula (17). The details of the obtained polymer additive are as shown in Table 3.

[0215]

[0216] <Comparative Example 6>

[0217] A polymer additive of Formula (18) was obtained by making the same as Example 1, except that the amount of each component was adjusted according to Table 2. The details of the obtained polymer additive are as shown in Table 3.

[0218]

[0219] <Comparative Example 7>

[0220] In Example 1, polyethylene glycol methyl ether methacrylate (Mn=500) was used instead of polyethylene glycol methacrylate (Mn=360), and the amount of each component was adjusted according to Table 2, except that the procedure was the same as in Example 1 to obtain the polymer additive of Formula (19). The details of the obtained polymer additive are as shown in Table 3.

[0221]

[0222] <Reference Example 1>

[0223] The above-mentioned dispersibility evaluation was performed without using polymer additives. That is, the dispersibility evaluation was performed using only methyl ethyl ketone. The results are shown in Table 3.

[0224]

[0225]

[0226] From the results of each example, the polymer additive satisfying the requirements of the present invention had excellent solubility in medium to high polarity solvents and resins. In addition, by using the polymer additive of the present invention, the dispersibility of the π-conjugated filler in medium to high polarity solvents could be improved.

[0227] In contrast, the polymer additives of Comparative Examples 1–3 and 6 did not show a maximum fluorescence peak in the range of 370 nm to 410 nm, and the polymer additives of Comparative Examples 4–5 had a total Hansen solubility parameter δ tot The polymer additive of Comparative Example 7 is outside the range of 17 or more and 24 or less, and does not have reactive functional groups and is a polymer additive that does not satisfy the requirements of the present invention. The polymer additives of each of these comparative examples had poor results in at least one of the solubility in medium to high polarity solvents, solubility in resins, and dispersibility of π-conjugated fillers in medium to high polarity solvents, and their performance was inferior compared to the examples.

Claims

Claim 1 Having an aromatic ring on a side chain or terminal of the polymer main chain, and also having at least one reactive functional group in the molecular structure, with a maximum fluorescence peak within the range of 370 nm to 410 nm, and a total Hansen solubility parameter δ represented by the following formula tot Polymer additive having a value of 17 or more and 24 or less.[Mathematical Formula 1] (δ in the above formula d , δ p , δ h ) Claim 2 In claim 1, the polar term δ of the Hansen solubility parameter p A polymer additive having a g of 0.5 or more and 19 or less. Claim 3 A polymer additive according to claim 1 or claim 2, wherein the aromatic ring comprises a condensed ring compound in which four or more six-membered rings are condensed. Claim 4 A polymer additive according to claim 3, wherein the number of condensed ring compounds is 1 or more and 5 or less per polymer chain. Claim 5 A polymer additive according to claim 1 or claim 2, wherein the reactive functional group comprises any one selected from the group consisting of a hydroxyl group, an acid anhydride group, and a trialkoxysilyl group. Claim 6 A polymer additive according to claim 1 or claim 2, wherein the number average molecular weight (Mn) measured by GPC is 4,000 or more and 100,000 or less. Claim 7 A polymer additive according to claim 1 or claim 2, having two maximum peaks of UV absorption within a range of 320 nm or more and 350 nm or less. Claim 8 A polymer additive according to claim 1 or claim 2, wherein the polymer main chain comprises (meth)acrylate. Claim 9 A polymer additive according to claim 1 or claim 2, having an alkyl group having 1 to 22 carbon atoms in its molecular structure. Claim 10 A filler-containing composition comprising a polymer additive described in claim 1 or claim 2, a filler, and a matrix which is at least one of a resin or a solvent. Claim 11 A filler-containing composition according to claim 10, wherein the filler is a thermally conductive filler. Claim 12 A filler-containing composition according to claim 10, wherein the resin comprises a curable resin and the curable resin comprises an epoxy compound.

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