JP2008024894A - Thermosetting resin composition and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermosetting resin composition that is excellent in heat resistance, mechanical strengths, flame retardancy, adhesion property and electric properties (dielectric properties) and is suitable as an information communication-related material such as a resin for an insulated substrate, and electronic equipment. <P>SOLUTION: The thermosetting resin composition comprises at least a polymer (A) having a cage-shaped silsesquioxane group covalently bonded thereto and a thermosetting resin (B). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a thermosetting resin composition containing caged silsesquioxane and an electronic device, and in particular, excellent in heat resistance, mechanical strength, flame retardancy, adhesion, and electrical properties (dielectric properties), The present invention relates to a thermosetting composition suitable as an information communication-related material, and an electronic device.

In recent years, electronic devices have been rapidly improved in performance, functionality, and downsizing, and the materials that make up electronic components are also strongly improved in functions such as heat resistance, mechanical strength, and low coefficient of thermal expansion. It has been demanded.
Conventionally, as materials constituting these electronic components, resins having very good heat resistance such as thermosetting resins such as phenol resins and epoxy resins, and main chain aromatic resins such as polyimide and polyethylene naphthalate have been used. It has been. This is because heat of 260 to 290 ° C. is applied in a solder reflow process that is performed when a device is mounted on a substrate as an electronic component, for example.

However, the fact is that the resin alone cannot satisfy the performance such as electrical characteristics, mechanical characteristics, and performance stability, and means for modifying the performance of the resin by adding additives are widely used.
As the additive, an inorganic material is often used, and examples thereof include silica, clay and the like. When these inorganic materials are added to the resin as a filler, effects such as improved heat resistance, improved mechanical performance, and low thermal expansion coefficient can be obtained. However, on the other hand, in order to add a filler to make a resin composite, for example, when used for wiring of an electronic circuit, it is indispensable to achieve high dispersion at the nano level as the wiring becomes finer. In order to achieve high dispersion of these fillers, the manufacturing process becomes complicated, and advanced dispersion control technology, coating technology, etc. are required to ensure stable performance.

Recently, as an inorganic material, a resin to which a silsesquioxane compound represented by the composition formula [RSiO _3/2 ] is added has been proposed. Silsesquioxanes include those having a three-dimensional crosslinked structure, those having a ladder-like structure (ladder structure), and those having a cage structure. The cage silsesquioxane itself has a closed structure, is thermally stable, and can be expected to have the same effect as an inorganic filler.

  In addition, as a method of adding / combining the cage silsesquioxane to the resin, a method of dispersing the cage silsesquioxane in the resin, a part or all of the substituents of the cage silsesquioxane is reactive. A polymer is synthesized by a method in which it is modified into a group and reacted with a resin, or a part or all of substituents of a cage silsesquioxane is modified into a polymerizable group and copolymerized alone or with other monomers. There are methods.

For example, polyethylene is used as the polymer, and the cage side silsesquioxane is covalently bonded to the polymer side chain to give a specific thermal history, thereby crystallizing the cage silsesquioxane into a plate shape, A system that exhibits a large heat resistance effect by adding a small amount of bowl-shaped silsesquioxane has been reported (see, for example, Non-Patent Document 1).
On the other hand, a resin composition for encapsulating an optical semiconductor made of silsesquioxane having at least two epoxy rings and B-staged has been proposed (for example, see Patent Document 1).
EB Coughlin et.al., Chemistry of Materials, Vol. 15, 4555-4561, 2003 JP 2005-263869 A

  However, in the method described in Non-Patent Document 1, the compatibility between the main chain and the cage silsesquioxane, the aggregation temperature of the cage silsesquioxane, the melting temperature of the main chain (crystal melting temperature), and the molding conditions The composition of stable performance, because the progress of the crystal of the cage silsesquioxane in the composition is greatly influenced by various factors such as the thermal history, the cage silsesquioxane structure, the state of mixing, etc. It was difficult to realize things.

  On the other hand, when a caged silsesquioxane that has been introduced into the polymer chain and has not been crystallized is added / introduced, for example, in order to obtain an effect of improving mechanical properties, Since it is necessary to introduce silsesquioxane, the physical properties of the resin greatly change (for example, it becomes hard and brittle), the molding / processing becomes difficult (for example, melt kneading becomes difficult), and the cost increases. There was a problem.

  Moreover, when caged silsesquioxane is dispersed and introduced into the resin in a single molecular state (not introduced into the polymer chain), it is difficult to uniformly disperse in the resin by heat treatment such as kneading. The cocoon-like silsesquioxane particles tend to aggregate and disperse into giant particles. This occurs due to the tendency of the cage silsesquioxane to aggregate. As described above, when the cocoon-like silsesquioxane is in the form of huge particles due to aggregation, it becomes the same as the usual addition of inorganic fine particles, and an effect such as improvement in heat resistance cannot be sufficiently obtained.

  Furthermore, it is possible to produce a fully dispersed cast product using a solvent that dissolves both the cage-like silsesquioxane monomolecule and the resin. In order to obtain, it is necessary to introduce a large amount of cage-like silsesquioxane. As in the case described above, the introduction of the cage-like silsesquioxane significantly changes the physical properties of the resin (for example, it becomes hard and brittle), making molding and processing difficult. (For example, melt kneading becomes difficult) and the cost is high.

  In particular, it is difficult to achieve crystallization of cage-like silsesquioxane with a thermosetting resin-based composition. In order to progress the crystallization of the cage silsesquioxane according to the temperature history, the cage silsesquioxane is first randomly arranged at a high temperature, and then slowly cooled to form the cage silsesquioxane. A method of crystallizing is used (refer to Non-Patent Document 1 for the crystallization process), but in the case of a thermosetting resin, curing may start at a high temperature and the crystallization process may not be taken. high. In addition, when the aging is performed to crystallize the cage silsesquioxane in a situation where the resin is not sufficiently cured, the temperature for curing is insufficient, and the curing time is likely to be extremely long or not cured.

  In addition, in the method proposed in Patent Document 1, the cage-shaped silsesquioxane is uniformly dispersed, and as described above, a sufficient effect cannot be obtained unless a large amount of cage-like silsesquioxane is added. As a result of blending, it becomes hard and brittle, and the cost increases.

  As described above, it has been technically difficult to obtain an effect such as improvement of heat resistance by crystals of caged silsesquioxane, particularly in thermosetting resins.

  Therefore, the present invention uses a crystal structure of a cage silsesquioxane even in a thermosetting resin composition, so that even if a small amount of cage silsesquioxane is added as a total amount, sufficient heat resistance is obtained. An object of the present invention is to provide a thermosetting resin composition and an electronic device that are improved in property, mechanical strength, and electrical characteristics.

  As a result of intensive studies in view of the above problems, the inventors of the present invention have a heat containing at least a polymer (A) having a cage-like silsesquioxane group covalently bonded thereto and a thermosetting resin (B). Even if the total amount of the curable resin composition is a small amount of bowl-shaped silsesquioxane added, sufficient heat resistance, mechanical strength, flame resistance, adhesion, and electrical properties (dielectric properties) The present invention has been completed.

（式（２）中、Ｒは炭素数１〜１０の有機基であり、Ｘは高分子（Ａ）の主鎖との結合部位を示す。）；
（５）前記高分子（Ａ）中の籠状シルセスキオキサン基に含まれる置換基Ｒが芳香族基であることを特徴とする前記（３）又は（４）に記載の熱硬化性樹脂組成物；
（６）前記高分子（Ａ）が、下記式（１’）で表される籠状シルセスキオキサン基を有する化合物（Ｍ）を反応させて得られることを特徴とする前記（１）又は（２）に記載の熱硬化性樹脂組成物
〔ＲＳｉＯ_3/2〕_n〔ＹＳｉＯ_3/2〕_m （１’）
（式（１’）中、Ｒは炭素数１〜１０の有機基であり、Ｙは高分子（Ａ）の主鎖又は側鎖との結合部位となりうる官能基を示す。ｎは４〜７の整数を示し、ｍは１〜４の整数を示し、ｎ＋ｍ＝８である。）；
（７）前記化合物（Ｍ）が、下記式（２’）で表されることを特徴とする前記（６）に記載の熱硬化樹脂組成物

（式（２’）中、Ｒは炭素数１〜１０の有機基であり、Ｙは高分子（Ａ）の主鎖との結合部位となりうる官能基を示す。）；
（８）前記高分子（Ａ）中の籠状シルセスキオキサン基に含まれる置換基Ｒが芳香族基であることを特徴とする前記（６）又は（７）に記載の熱硬化性樹脂組成物；
（９）前記熱硬化性樹脂（Ｂ）がエポキシ樹脂であることを特徴とする前記（１）〜（８）の何れか一項に記載の熱硬化性樹脂組成物；
（１０）前記熱硬化性樹脂（Ｂ）がグリシジルエーテル型のエポキシ樹脂である前記（１）〜（９）の何れか一項に記載の熱硬化性樹脂組成物：
（１１）前記（１）〜（１０）の何れか一項に記載の熱硬化性樹脂組成物を含む電子機器；を提供する。 That is, the present invention
(1) A thermosetting resin composition comprising at least a polymer (A) having two or more caged silsesquioxane groups covalently bonded thereto, and a thermosetting resin (B);
(2) The thermosetting resin composition according to (1), wherein the polymer (A) has two or more cage-like silsesquioxane groups having a crystal structure;
(3) The thermosetting resin composition as described in (1) or (2) above, wherein the cage silsesquioxane group in the polymer (A) is represented by the following formula (1): [RSiO _3/2 ] _n [XSiO _3/2 ] _m (1)
(In Formula (1), R is a C1-C10 organic group, X shows the coupling | bond part with the principal chain or side chain of a polymer (A), n shows the integer of 4-7, m represents an integer of 1 to 4, and n + m = 8);
(4) The cage-like silsesquioxane group in the polymer (A) is represented by the following formula (2), according to any one of (1) to (3), Thermosetting resin composition

(In the formula (2), R is an organic group having 1 to 10 carbon atoms, and X represents a binding site with the main chain of the polymer (A));
(5) The thermosetting resin according to (3) or (4) above, wherein the substituent R contained in the cage silsesquioxane group in the polymer (A) is an aromatic group. Composition;
(6) The polymer (A) obtained by reacting the compound (M) having a cage-shaped silsesquioxane group represented by the following formula (1 ′): Thermosetting resin composition according to (2) [RSiO _3/2 ] _n [YSiO _3/2 ] _m (1 ′)
(In the formula (1 ′), R represents an organic group having 1 to 10 carbon atoms, Y represents a functional group that can be a binding site with the main chain or side chain of the polymer (A), and n represents 4 to 7). M represents an integer of 1 to 4, and n + m = 8);
(7) The thermosetting resin composition according to (6), wherein the compound (M) is represented by the following formula (2 ′):

(In the formula (2 ′), R represents an organic group having 1 to 10 carbon atoms, and Y represents a functional group that can be a binding site with the main chain of the polymer (A));
(8) The thermosetting resin according to (6) or (7), wherein the substituent R contained in the cage silsesquioxane group in the polymer (A) is an aromatic group. Composition;
(9) The thermosetting resin composition according to any one of (1) to (8), wherein the thermosetting resin (B) is an epoxy resin;
(10) The thermosetting resin composition according to any one of (1) to (9), wherein the thermosetting resin (B) is a glycidyl ether type epoxy resin:
(11) An electronic device comprising the thermosetting resin composition according to any one of (1) to (10).

The thermosetting resin composition of the present invention is excellent in heat resistance, mechanical strength, flame retardancy, adhesion, and electrical properties (dielectric properties), and thereby, electronic circuit substrate materials such as insulating substrates corresponding to high frequencies, etc. Can be provided.
Further, by using such a thermosetting resin composition, it is possible to provide an information device substrate such as a computer with higher performance (high-speed communication possible) and stable performance. In particular, the thermosetting resin composition of the present invention is useful as a material for an insulating substrate.

  Next, an embodiment of the present invention will be described. The following embodiment is an example for explaining the present invention, and is not intended to limit the present invention only to this embodiment. The present invention can be implemented in various forms without departing from the gist thereof.

  The thermosetting resin composition of the present invention contains at least a polymer (A) in which two or more caged silsesquioxane groups are covalently bonded, and a thermosetting resin (B).

[Polymer (A)]
(Soil-like silsesquioxane group)
In the polymer (A), two or more caged silsesquioxane groups are covalently bonded. Here, the cage silsesquioxane group is a residue of cage silsesquioxane and its derivative, that is, one or more atoms of cage silsesquioxane and its derivative are eliminated, 1 or A group having two or more binding sites is meant.

A cage-like silsesquioxane is a compound having a closed structure (a cage structure) obtained by condensation of a compound represented by the following formula (3).
R-Si (Z) ₃ (3)
(In Formula (3), R is an arbitrary substituent, and a plurality of different types of substituents may be used. Z is a halogen such as Cl, OH, or OCH ₃ , OC ₂ H ₅ , OC ₃ H _7. Represents an alkoxy group such as

The cage silsesquioxane group is, for example, a residue of a compound represented by the following formula (4).
[RSiO _3/2 ] _n (4)
(In formula (4), R is an arbitrary substituent, and a plurality of different types of substituents may be used. N is an integer of 5 to 12.)

  In the above formulas (3) to (4), R is, for example, an organic group having 1 to 10 carbon atoms, hydrogen, a hydroxy group, or halogen. From the viewpoint of improving the stability of the cage silsesquioxane, R is preferably an organic group having 1 to 10 carbon atoms.

  In the cage silsesquioxane group, in the above formula (4), n is preferably 6, 8, 10 or 12.

In the above formula (4), when n is 6, 8, 10, or 12, a closed siloxane structure is formed. For example, when n is 8, the structure represented by the following formula (5) is obtained. .

  In particular, the cage silsesquioxane represented by the formula (5) where n is 8 is structurally stable, easy to synthesize, and easily available on the market, so that it can be suitably used.

On the other hand, in the above formula (4), when n is 5, 7, 9, or 11, a part of the eaves structure is open. For example, when n is 7, it is represented by the following formula (6). It becomes a structure.

  In the present invention, n may be 5, 7, 9, or 11. In this case, the structure of the cage silsesquioxane is slightly unstable, but the residual silanol group reacts with a thermosetting resin (for example, epoxy resin), and the cage silsesquioxane and the thermosetting resin There is a possibility of forming a strong bond. When n is 5, 7, 9, or 11, it is necessary to take into account changes in physical properties such as reaction during production and use.

  The polymer (A) preferably has two or more caged silsesquioxane groups having a crystal structure.

The cage silsesquioxane group in the polymer (A) is preferably one represented by the following formula (1).
[RSiO _3/2 ] _n [XSiO _3/2 ] _m (1)
(In Formula (1), R is a C1-C10 organic group, X shows the coupling | bond part with the principal chain or side chain of a polymer (A), n shows the integer of 4-7, m represents an integer of 1 to 4, and n + m = 8.)

  Formula (1) is obtained by substituting 1-4 R in the binding site X with the polymer (A) in the general formula (4) of the cage silsesquioxane group.

（式（２）中、Ｒは炭素数１〜１０の有機基であり、Ｘは高分子（Ａ）の主鎖との結合部位を示す。 The cage silsesquioxane group in the polymer (A) is preferably represented by the following formula (2).

(In Formula (2), R is a C1-C10 organic group, X shows the coupling | bond part with the principal chain of a polymer (A).

The polymer (A) is preferably obtained by reacting a compound (M) having a cage-shaped silsesquioxane group represented by the above formula (1 ′).
That is, the polymer (A) is obtained by reacting the predetermined polymer with the compound (M) having a cage-shaped silsesquioxane group represented by the above formula (1 ′), and the main chain of the polymer. Alternatively, it may be obtained by reacting the functional group of the compound (M) with the side chain.
The compound (M) is preferably represented by the above formula (2 ′).

The organic group having 1 to 10 carbon atoms, which is preferably R, is preferably an aromatic group. Examples of the aromatic group include an aryl group and an aralkyl group.
Specific examples of preferable aryl group as R include aromatic groups such as phenyl group and naphthyl group.
Specific examples of preferable aralkyl groups as R include an ethylphenyl group.
In the above, a halogen group, an amino group, an ether group, a hydroxyl group, an alkoxy group, or the like may be substituted for a part of hydrogen of the alkyl group, aryl group, or aralkyl group.

The organic group having 1 to 10 carbon atoms, which is preferable R, may be an alkyl group. On the other hand, when R is hydrogen, an alkoxy group, a hydroxy group, or a halogen, it is necessary to consider the change in physical properties during production and use.
Specific examples of preferred alkyl groups as R include straight and branched alkyl groups such as methyl, ethyl, propyl, n-butyl, i-butyl, n-octyl, and i-octyl, cyclopentyl And alicyclic alkyl groups such as a cyclohexyl group.
These can be easily synthesized by a hydrosilylation reaction between a corresponding vinyl compound and a caged silsesquioxane having a hydrogen atom on silicon. For example, C.I. It can be synthesized by the method described in Bollon et al., Chemistry of materials, Vol. 9, pp. 1474-1479, 1997.

From the viewpoint of easy synthesis of the compound, R is preferably a methyl group, an ethyl group, an i-butyl group, an i-octyl group, a cyclopentyl group, a cyclohexyl group, or a phenyl group.
Further, among these substituents R, a cyclopentyl group, a cyclohexyl group, and a phenyl group are more preferable because they are thermally stable and the interaction between cage-like silsesquioxanes is strong and a crystallized structure is easily formed.

  In the present invention, the selection of the substituent R is determined in consideration of the compatibility with the resin, the relationship between the resin melting temperature and the crystallization temperature of the cage silsesquioxane, and the like. At this time, the substituent R on the cage silsesquioxane may be a mixture of a plurality of types of substituents. However, the same substituent is preferred in terms of synthesis. Moreover, when the substituents R are the same, the cage silsesquioxane can be crystallized more uniformly.

(Covalent bond between polymer (A) and caged silsesquioxane)
In the present invention, the polymer (A) is formed by covalently bonding two or more caged silsesquioxane groups.
The bond between the caged silsesquioxane and the polymer (A) is not particularly limited as long as it is a covalent bond, and there should be at least one bond between the caged silsesquioxane and the polymer (A). It may have a plurality of bonds.

FIGS. 1-4 is a schematic diagram which shows each example of the coupling | bonding form of a polymer (A) and a cage-like silsesquioxane. 1-4, a cage-like silsesquioxane group is schematically shown as a cube, and chemical bonds and polymer chains are shown as lines.
The form of the covalent bond of the cage silsesquioxane group in the polymer (A) is as follows: side chain type shown in FIG. 1, terminal type shown in FIG. 2, main chain type shown in FIG. Any of the star shapes shown may be used, and the polymer main chain of FIG. 1 may be formed into a ring shape or a composite shape thereof.
From the viewpoint of obtaining sufficient weight% of cage-like silsesquioxane, the side chain type of FIG. 1 or the main chain type of FIG. 3 is preferred.

  As shown in FIG. 1, in the first example, a polymer chain is used as a main chain, and a cage-like silsesquioxane is introduced as a side chain through a covalent bond. This corresponds to the case of n = 7 and m = 1 in the formula (1).

The structure shown in FIG. 1 is a polymerization and / or condensation of, for example, a vinyl group, a styryl group, a (meth) acryloyl group, an alkoxysilyl group, or a chlorosilyl group as the substituent Y that gives the binding site X of the cage silsesquioxane. The structure shown in FIG. 1 can be obtained by having at least one possible substituent and performing homopolymerization or copolymerization with other monomers.
These substituents Y are more preferable if they are compatible with the thermosetting resin (B).
In addition, hydroxy groups, amino groups, phenols, alkoxysilanes, chlorosilanes, hydrosilanes, epoxies, halogens, isocyanates, norbornenyls, olefins, thiols, etc. are introduced into the cage silsesquioxane as substituents. Similarly, the structure of FIG. 1 can also be obtained by reacting with a polymer having a group capable of reacting. Furthermore, the structure of FIG. 1 can also be obtained by introducing trichlorosilane into the polymer and reacting the silsesquioxane precursor represented by the above formula (6) partially opened. These substituents are more preferable if they are compatible with the thermosetting resin (B).

  Specific examples of the cage silsesquioxane having a substituent capable of polymerization and / or condensation are given below, but the present invention is not limited thereto. Moreover, in specific examples, POSS (registered trademark; Hybrid Plastics Co., Ltd.) represents a cage silsesquioxane structure of n = 8 shown in the above formula (5), and polymerizable group = other substituents = The notation “skeleton” is used.

That is, as having an acryloyl group, 3-propylacryloyl = heptaisobutyl = POSS (registered trademark), as having a methacryloyl group, 3-propylmethacryloyl = heptaisobutyl = POSS (registered trademark), 3-propylmethacryloyl = Heptaisooctyl = POSS (registered trademark), 3-propylmethacryloyl = heptaphenyl = POSS (registered trademark), 3-propylmethacryloyl = heptacyclopentyl = POSS (registered trademark), 3-methacryloylpropyldimethylsilyloxy = heptacyclopentyl = POSS (Registered trademark), as having a styryl group, 4-vinylphenyl = heptacyclopentyl = POSS (registered trademark), as having a norbornenyl group, norbornenyl ethyl = As containing olefins such as ptaisobutyl = POSS (registered trademark), norbornenylethyl = heptacyclopentyl = POSS (registered trademark), norbornenylethyldimethylsilyloxy = heptacyclopentyl = POSS (registered trademark), vinyl group, Allyl = heptaisobutyl = POSS®, vinyl = heptaisobutyl = POSS®, allyldimethylsilyloxy = heptacyclopentyl = POSS®, vinyldiphenylsilyloxy = heptacyclopentyl = POSS®, Methylphenylvinylsilyloxy = heptacyclopentyl = POSS®, allyl = heptacyclopentyl = POSS®, vinyldimethylsilyloxy = heptacyclopentyl = POSS®, Cycloalkenyl = hepta cyclopentyl = POSS (registered trademark), trivinyl Siri b carboxymethyl = hepta cyclopentyl = POSS (registered trademark) and the like are preferable.
These raw materials can be obtained from Hybrid Plastics and Aldrich, and can also be synthesized from a corresponding cage silsesquioxane precursor.

In the second example shown in FIG. 2, caged silsesquioxane is introduced into one or both ends of the polymer chain. Also in this case, a compound corresponding to the case of n = 7 and m = 1 in the formula (1) is used.
In FIG. 2, the polymer chain is a linear polymer, but the polymer chain need not be linear and may be branched. One mode when the polymer chain is branched is the star shape shown in FIG. As shown in FIG. 4, the cage silsesquioxane may be introduced at all ends or may be introduced at some ends.

  In order to introduce a cage silsesquioxane at the end of the polymer chain, for example, a method of performing living polymerization and adding a terminator containing the cage silsesquioxane at the termination stage, a substituent present at the polymer end And a method of reacting a substituent of a cage silsesquioxane with a substituent of the cage silsesquioxane, a method of using a substituent of the cage silsesquioxane as a base point for polymerization, and the like.

  Examples of the substituent of the cage silsesquioxane that can be used to obtain the structures shown in FIGS. 2 and 4 include polymerization of vinyl group, styryl group, (meth) acryloyl group, alkoxysilyl group, chlorosilyl group, and the like. Examples thereof include reactive substituents such as a condensable substituent, hydroxy group, amino group, phenol, alkoxysilane, chlorosilane, hydrosilane, epoxy, halogen, isocyanate, norbornenyl, olefin, and thiol.

The third example shown in FIG. 3 has a structure in which caged silsesquioxane is introduced into the skeleton of the polymer chain.
In order to incorporate a cage silsesquioxane into the polymer skeleton, the cage silsesquioxane has two or more functional groups, that is, in formula (1), n = 4 to 6, m = 4 This corresponds to the case of ˜2 (where n + m = 8). Is used. The functional group used here is the above-described polymerization and / or condensable substituent, reactive substitution or the like.

  Here, the structures shown in FIG. 1, FIG. 2 and FIG. 4 show the case where only the compound of n = 7 and m = 1 is used in the formula (1), and the structure shown in FIG. In the formula (1), the case where only the compound of n = 6 and m = 2 is illustrated, but it is not necessarily limited thereto, n = 4 to 7, m = 4 to 1 (however, n + m = 8 ) May be used in combination. However, when a polymer having a molecular weight exceeding m = 2 is used, the polymer (A) tends to have a three-dimensional cross-linked structure, and the cage silsesquioxane hardly takes a crystallized structure.

In addition, a polymer (A) containing a caged silsesquioxane in the side chain of the polymer chain shown in FIG. 1, and a polymer containing a caged silsesquioxane at the end of the polymer chain shown in FIG. A), a polymer (A) containing a cage silsesquioxane in the skeleton of the polymer chain shown in FIG. 3, and a cage silsesquioxane at all ends of the branched polymer chain shown in FIG. The polymer (A) containing oxane may be a copolymer of a monomer having cage-like silsesquioxane and a monomer not containing cage-like silsesquioxane. A plurality of monomers that do not contain sesquioxane may be used.
When the copolymer is used, it may be a random copolymer or a block copolymer, and these are appropriately selected according to the use and process in which the composition of the present invention is used.

(Crystal structure of two or more caged silsesquioxane groups)
In the present invention, the polymer (A) has a crystal structure in which two or more caged silsesquioxane groups are present. The crystal structure is a structure formed by self-organization of cage-shaped silsesquioxane groups. The presence or absence of the crystal structure of cage-shaped silsesquioxane is determined by wide-angle X-ray scattering (WAXS). It can be confirmed by a scattering peak at 1 to 1.2 nm.

In the present invention, the molecular weight, molecular weight distribution, and the like of the polymer (A) in which two or more caged silsesquioxane groups are covalently bonded are not particularly limited, and are appropriately determined depending on the use / process in which the composition of the present invention is used. Selected. For example, a resin having a polystyrene-equivalent weight average molecular weight of several thousand to about one million can be used.
The lower limit is preferably 1000, more preferably 5000, still more preferably 20,000, and the upper limit is preferably 500,000, more preferably 100,000, still more preferably 60,000. When the weight average molecular weight is small, it is difficult to obtain the effect of the polymer (A). When the weight average molecular weight is large, the crystal of the polymer (A) becomes large, and only the same effect as a normal inorganic filler can be obtained.
Furthermore, in the present invention, the polymer (A) in which two or more cage-like silsesquioxane groups are covalently bonded has one or more functional groups capable of covalently bonding to the thermosetting resin (B) or a curing agent described later. You may have.

In the thermosetting resin composition of the present invention, from the viewpoint of further achieving the object of the present invention, the cage silsesquioxane group is preferably 20 to 100% by weight based on the total amount of the polymer (A). More preferably, it is 50 to 100% by weight.
The weight% of the cage silsesquioxane group in the polymer (A) may be determined by the charging ratio because radical charging or the like almost reflects the charging ratio at the time of polymerization. It can also be measured directly using a magnetic resonance apparatus and directly calculated from the hydrogen nucleus ratio.

[Thermosetting resin (B)]
The thermosetting resin (B) used in the present invention is not particularly limited, and phenol resin, melamine resin, epoxy resin, unsaturated polyester resin, bismaleimide resin and the like can be used. As described above, the cage silsesquioxane can adjust the compatibility with each thermosetting resin by changing various substituents on the silicon atom (R in the formula (1)). Respond to resin.

  The thermosetting resin (B) is preferably an epoxy resin. Epoxy resin is highly versatile, has good compatibility with caged silsesquioxane, and is a thermosetting resin composition that is more excellent in heat resistance and reliability by combining with the above polymer (A). Can be obtained.

  As the epoxy resin used in the present invention, a bifunctional or higher epoxy compound, for example, a known epoxy resin such as a glycidyl ether type, a glycidyl ester type, a glycidyl amine type, and an alicyclic type epoxy compound is preferably used. it can.

Among these epoxy resins, in particular, glycidyl ether type epoxy resins have better compatibility (than glycidyl ester type epoxy resins), better electrical properties (than glycidyl amine type epoxy resins), and (alicyclic type). It is excellent in heat resistance (than epoxy resin), is inexpensive and available in large quantities, and can be used more suitably.
Specific examples of glycidyl ether type epoxy resins include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol S type epoxy compounds, brominated bisphenol A type epoxy compounds, hydrogenated bisphenol A type epoxy compounds, and biphenyl. Type epoxy compound, naphthalene type epoxy compound, dicyclopentadiene type epoxy compound, phenol novolac type epoxy compound, cresol novolac type epoxy compound, bisphenol A novolac type epoxy compound, diglycidyl etherified product of polyfunctional phenol, trishydroxymethane type epoxy compound , Tetraphenolethane type epoxy compounds, butadiene type epoxy compounds and the like.

  The above-mentioned epoxy resin may be a hydrogenated product, a brominated product or the like, and may be used alone or in combination of two or more.

An epoxy compound curing agent may be added to the thermosetting resin composition of the present invention in order to cure the epoxy compound more efficiently.
The epoxy compound curing agent may be any epoxy compound curing agent that has been conventionally used as a curing agent for epoxy compounds. For example, amine compounds, compounds such as polyaminoamide compounds synthesized from amine compounds, Examples include tertiary amine compounds, imidazole compounds, hydrazide compounds, melamine compounds, acid anhydrides, phenol compounds, thermal latent cationic polymerization catalysts, photolatent cationic polymerization initiators, dicyandiamide, and derivatives thereof. These hardening | curing agents may be used independently and 2 or more types may be used together.

  Examples of the amine compound include chain aliphatic amines such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, diethylaminopropylamine, methylenedianiline, benzylmethylamine, polyoxypropylenediamine, and polyoxypropylenetriamine; Derivatives thereof; mensendiamine, isophoronediamine, bis (4-amino-3-methylcyclohexyl) methane, diaminodicyclohexylmethane, bis (aminomethyl) cyclohexane, N-aminoethylpiperazine, 3,9-bis (3 -Aminopropyl) cycloaliphatic amines such as 2,4,8,10-tetraoxaspiro (5,5) undecane, aminoethylpiperazine and derivatives thereof; m-xylenediamine, diaminodiphe Aromatic sulfone such as rusulfone, α- (m / paminophenyl) ethylamine, m-phenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, α, α-bis (4-aminophenyl-p-diisopropylbenzene, and derivatives thereof Can be mentioned.

  Examples of the compound synthesized from the amine compound include the amine compound, succinic acid, adipic acid, azelaic acid, sebacic acid, dodecadic acid, isophthalic acid, terephthalic acid, dihydroisophthalic acid, tetrahydroisophthalic acid, hexahydro Polyaminoamide compounds and derivatives thereof synthesized from carboxylic acid compounds such as isophthalic acid; Polyaminoimide compounds and derivatives thereof synthesized from the above amine compounds and maleimide compounds such as diaminodiphenylmethane bismaleimide; The above amine compounds and ketone compounds Ketimine compounds synthesized from these and derivatives thereof; polyamino compounds synthesized from the above amine compounds and compounds such as epoxy compounds, urea, thiourea, aldehyde compounds, phenol compounds, acrylic compounds, and the like. Derivatives, and the like.

  Examples of the tertiary amine compound include N, N-dimethylpiperazine, pyridine, picoline, benzyldimethylamine, 2- (dimethylaminomethyl) phenol, 2,4,6-tris (dimethylaminomethyl) phenol, 1, And 8-diazabiscyclo [5,4,0] unde-7-cene-1 and derivatives thereof.

  Examples of the imidazole compound include 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, and derivatives thereof.

  The hydrazide compound is not particularly limited. For example, 1,3-bis (hydrazinocarboethyl) -5-isopropylhydantoin, 7,11-octadecadien-1,18-dicarbohydrazide, eicosane diacid dihydrazide, Examples include adipic acid dihydrazide and its derivatives.

  Examples of the melamine compound include 2,4-diamino-6-vinyl-1,3,5-triazine and derivatives thereof.

  Examples of the acid anhydride include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol bisanhydro trimellitate, glycerol tris anhydro trimellitate, Methyltetrahydrophthalic anhydride, tetrahydrophthalic anhydride, nadic anhydride, methylnadic anhydride, trialkyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, 5- (2,5-di Oxotetrahydrofuryl-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, trialkyltetrahydrophthalic anhydride-maleic anhydride adduct, dodecenyl succinic anhydride, polyazelenic anhydride, polydodecanedioic acid Anhydride, chlorendic anhydride And derivatives thereof.

  The phenol compound is not particularly limited, and examples thereof include phenol novolak, o-cresol novolak, p-cresol novolak, t-butylphenol novolak, cresol novolak having a dicyclopentadiene structure, and derivatives thereof.

[Mixing and curing of polymer (A) and thermosetting resin (B)]
The mixing ratio of the polymer (A) in which two or more caged silsesquioxane groups of the present invention are covalently bonded to the thermosetting resin (B) is not particularly limited. Since the present invention is characterized by curing by introducing a small amount of caged silsesquioxane groups, it is preferable that the polymer (A) is added in a small amount. As a specific example, polymer (A): thermosetting resin (B) by weight ratio = 0.01: 100 to 20: 100, preferably 0.05: 100 to 10: 100, more preferably 0.1 to 5: 100. Here, the quantity of a thermosetting resin (B) points out what contains the main ingredient, the hardening | curing agent, and the curing catalyst.

  In the present invention, even when the ratio of the polymer (A) is relatively low, the molecular motion of the thermosetting resin (B) due to crystallization is greatly suppressed, so that mechanical characteristics, thermal characteristics, and the like are improved. I can do it. Since the addition amount of the polymer (A) is small, the cost can be suppressed and the variation in process suitability of the thermosetting resin (B) can be suppressed.

  The mixing of the polymer (A) and the thermosetting resin (B) can be performed by any known method, and is not particularly limited as long as both can be sufficiently mixed. Sufficient mixing refers to a situation in which no conspicuous scattering occurs in the visible light region in a mixture of the two. For example, a method in which both are mixed and kneaded by applying heat, a method in which both or one is dissolved in a solvent and then mixed and stirred is used, and in the case of kneading, a known kneader, roll, press or the like may be used. In addition, when dissolving in a solvent, a stirrer, a stirring blade, a dispenser, or the like can be used.

In addition, a filler may be added to the thermosetting resin composition of the present invention for adjusting the viscosity of the thermosetting resin composition and adjusting various physical properties of the resulting thermosetting resin molding.
The filler is not particularly limited as long as it is an inorganic filler that has been conventionally used in the molding of thermosetting resins. For example, calcium carbonate, magnesium carbonate, silicon oxide, aluminum oxide, titanium oxide, Examples thereof include magnesium hydroxide, aluminum hydroxide, calcium hydroxide, barium sulfate, magnesium sulfate, mica, talc, clay, zeolite, and carbon black. Furthermore, antioxidants, heat stabilizers, light stabilizers, ultraviolet absorbers, weathering agents, lubricants, compatibilizers, colorants, etc. are added as additives to the thermosetting resin composition of the present invention. Also good. These additives may be used alone or in combination of two or more.

The mixture thus obtained is given a desired shape by casting, pressing, casting or the like. The shape is not particularly limited, and the shape is given according to the application.
The thermosetting resin composition provided with the shape is cured by heating or the like. The heating method is not particularly limited, and any method such as heating with an oven, infrared heating, induction heating, or the like can be used. The heating temperature is not particularly limited, and a temperature corresponding to the composition of the obtained thermosetting resin composition can be selected. For example, the heat curing temperature is 40 ° C. or higher and 300 ° C. or lower, but is not limited thereto.
In heat curing, the temperature may be increased stepwise without increasing the temperature at once, or the temperature may be increased in an inclined manner. Alternatively, lamination or pressing may be performed on a so-called B stage which is not completely cured but semi-cured, and then completely cured.

[Application example]
The electronic device of the present invention includes the thermosetting resin composition. That is, an electronic device including part or all of a molded body produced from the thermosetting resin composition is excellent in heat resistance, mechanical strength, flame retardancy, adhesion, and electrical characteristics.
The electronic device of the present invention may include an insulating substrate containing the thermosetting resin composition, a molded body such as a film or a substrate, and the like as constituent elements.

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples. Those skilled in the art can implement various modifications as well as the following embodiments, and such modifications are also included in the scope of the claims.
The materials used in the examples and comparative examples were not purified unless otherwise specified, and the obtained materials were used as they were. In particular, all reagents not listed as a manufacturer were obtained from Wako Pure Chemical.

[Synthesis Example 1] Synthesis of polymer (A-1) having caged silsesquioxane group 3-methacryloylpropyl = heptaphenyl = POSS (registered trademark; manufactured by Hybrid Plastics, product number MA0734) in a 10 ml eggplant flask 1.0 g, azoisobutyronitrile 14.3 mg, and toluene 1.7 ml were added, and the atmosphere in the flask was replaced with nitrogen, followed by heating in a 60 ° C. oil bath for 24 hours.
The obtained reaction mixture was dissolved in 20 ml of tetrahydrofuran and added dropwise to 300 ml of methanol for reprecipitation. Thereafter, reprecipitation was further carried out in the same manner with tetrahydrofuran-cyclohexane and further with tetrahydrofuran-methanol to remove unreacted monomers. The obtained precipitate was dried at 60 ° C. under vacuum to obtain a polymer (A-1) having a caged silsesquioxane group.
When this polymer (A-1) was dissolved in tetrahydrofuran and the molecular weight was measured with a gel permeation chromatograph (GPC, manufactured by Tosoh Corp., Model No. 8020), the weight average molecular weight (Mw) in terms of polystyrene was 48,000. .
When the obtained polymer (A-1) was measured by wide angle X-ray scattering (WAXS), it had a scattering peak at 1.1 to 1.2 nm.

[Synthesis Example 2] Synthesis of polymer (A-2) having cage-like silsesquioxane group 3-methacryloylpropyl = heptaphenyl = POSS (registered trademark; manufactured by Hybrid Plastics Co., Ltd., product number MA0734) in a 10 ml eggplant flask 0.91 g, azoisobutyronitrile 15.0 mg, methyl methacrylate 0.1 g, and toluene 1.5 ml were added, and the atmosphere in the flask was replaced with nitrogen, followed by heating in an 80 ° C. oil bath for 3 hours.
The obtained reaction mixture was post-treated in the same manner as in Synthesis Example 1 to obtain a polymer (A-2) having a caged silsesquioxane group. When the molecular weight of this polymer (A-2) was measured, it was 36,000 in terms of polystyrene-converted weight average molecular weight (Mw).
When the obtained polymer (A-2) was measured by wide-angle X-ray scattering (WAXS), it had a scattering peak at 1.1 to 1.2 nm.

[Example 1]
20 mg of polymer (A-1) is mixed with 200 mg of Epicoat 807 (epoxy base agent, Japan Epoxy Resin) 50 wt% toluene solution and 100 mg of Epicoat EMI24 (epoxy curing agent, Japan Epoxy Resin) 6 wt% toluene solution. The mixture was stirred at 60 ° C. for 30 minutes to obtain a completely transparent thermosetting resin composition solution. This solution was cast on a PTFE sheet and cured by heating at 80 ° C. for 1 hour, 120 ° C. for 2.5 hours, and 180 ° C. for 1.5 hours. A light yellow transparent film-like cured product having a thickness of 60 μm was obtained.

[Example 2]
20 mg of polymer (A-2) is mixed with 200 mg of 50 wt% toluene solution of Epicoat 807 (epoxy base agent, manufactured by Japan Epoxy Resin) and 100 mg of 6 wt% toluene solution of Epicoat EMI24 (produced by Epoxy curing agent, manufactured by Japan Epoxy Resin). The mixture was stirred at 60 ° C. for 30 minutes to obtain a completely transparent thermosetting resin composition solution. This solution was cast on a PTFE sheet and cured by heating at 80 ° C. for 1 hour, 120 ° C. for 2.5 hours, and 180 ° C. for 1.5 hours. A light yellow transparent film-like cured product having a thickness of 60 μm was obtained.

[Comparative Example 1]
3-methacryloylpropyl = heptaphenyl = POSS (registered trademark; manufactured by Hybrid Plastics Co., Ltd., product number MA0734) monomer 20 mg, Epicoat 807 (epoxy main agent, manufactured by Japan Epoxy Resin) 50 wt% toluene solution 200 mg, and Epicoat EMI24 (epoxy) Curing agent (manufactured by Japan Epoxy Resin) 100 mg of 6 wt% toluene solution was mixed and stirred for 30 minutes at 60 ° C. to obtain a completely transparent thermosetting resin composition solution. This solution was cast on a PTFE sheet and cured by heating at 80 ° C. for 1 hour, 120 ° C. for 2.5 hours, and 180 ° C. for 1.5 hours. A light yellow and translucent film-like cured product having a thickness of 60 μm was obtained.

[Comparative Example 2]
Epicoat 807 (epoxy base material, manufactured by Japan Epoxy Resin) 50 wt% toluene solution 200 mg and Epicoat EMI24 (epoxy curing agent, manufactured by Japan Epoxy Resin) 6 wt% toluene solution 100 mg are mixed together to form a completely transparent thermosetting resin composition. A product solution was obtained. This solution was cast on a PTFE sheet and cured by heating at 80 ° C. for 1 hour, 120 ° C. for 2.5 hours, and 180 ° C. for 1.5 hours. A light yellow transparent film-like cured product having a thickness of 60 μm was obtained.

[Thermal properties evaluation]
Each film obtained in Examples and Comparative Examples was placed in a thermogravimetric analyzer (DTG-60 manufactured by Shimadzu Corporation), heated in air at a rate of 20 ° C./min, and 5% weight loss temperature ( Td5) (° C.) was measured. The obtained film-like cured product was measured by wide-angle X-ray scattering (WAXS), and the presence or absence of a scattering peak of 1.1 to 1.2 nm was measured. The results are shown in Table 1.

  As is apparent from the results shown in Table 1, an epoxy resin having a polymer (A) containing a silsesquioxane group (practical example 2) versus an epoxy resin containing no silsesquioxane group-containing compound (Comparative Example 2) In Example 1 and Example 2), the 5% weight loss temperature was improved by 10 ° C. or more. In addition, the one containing a silsesquioxane group but not polymerized (Comparative Example 1) is slightly more heat resistant than the one having no silsesquioxane group (Comparative Example 2). However, it was not a big change.

  That is, in the case where the silsesquioxane groups are densely packed in the polymer side chain (Examples 1 and 2), the silsesquioxane group covalently bonded to the polymer (A) because it was transparent. It is presumed that silsesquioxanes derived from do not form huge aggregates. Furthermore, since the improvement in heat resistance has occurred remarkably, it has a crystal structure that exerts a strong thermomolecular motion restraining effect on the whole resin (even for components derived from the thermosetting resin (B) after curing). It is presumed that a fine aggregated structure is taken and dispersed in the resin composition. On the other hand, even if it has a silsesquioxane group, it is not particularly easy to take a crystal structure, and it has a silsesquioxane group in a monomer state that is dispersed almost uniformly (Comparative Example 1). Only a slight improvement in heat resistance was observed. Moreover, since it was translucent, it is estimated that the silsesquioxane group has formed the huge aggregation.

From this, the thermosetting resin composition characterized in that it contains at least the polymer (A) having two or more silsesquioxane groups covalently bonded thereto and the thermosetting resin (B). It has been found that by using the crystal structure of the cage silsesquioxane, the heat resistance is sufficiently improved even when a small amount of cage silsesquioxane is added as a total amount.
Furthermore, improvement in mechanical strength, improvement in electrical characteristics, and the like can be expected, and it has been found that by using this thermosetting composition, an excellent electronic device can be provided.

It is a schematic diagram which shows the 1st example of the coupling | bonding form of the polymer chain in a resin, and a cage-like silsesquioxane. It is a schematic diagram which shows the 2nd example of the coupling | bonding form of the polymer chain in a resin, and a cage-like silsesquioxane. It is a schematic diagram which shows the 3rd example of the coupling | bonding form of the polymer chain in a resin, and a cage-like silsesquioxane. It is a schematic diagram which shows the 4th example of the coupling | bonding form of the polymer chain in a resin, and a cage-like silsesquioxane.

Claims (11)

A polymer (A) in which two or more cage-like silsesquioxane groups are covalently bonded;
A thermosetting resin composition comprising at least a thermosetting resin (B).   2. The thermosetting resin composition according to claim 1, wherein the polymer (A) has two or more cage-like silsesquioxane groups having a crystal structure. The thermosetting resin composition according to claim 1 or 2, wherein the cage silsesquioxane group in the polymer (A) is represented by the following formula (1).
[RSiO _3/2 ] _n [XSiO _3/2 ] _m (1)
(In Formula (1), R is a C1-C10 organic group, X shows the coupling | bond part with the principal chain or side chain of a polymer (A), n shows the integer of 4-7, m represents an integer of 1 to 4, and n + m = 8.) The thermosetting resin composition according to any one of claims 1 to 3, wherein the cage silsesquioxane group in the polymer (A) is represented by the following formula (2).

(In Formula (2), R is an organic group having 1 to 10 carbon atoms, and X represents a binding site with the main chain of the polymer (A).)   The thermosetting resin composition according to claim 3 or 4, wherein the substituent R contained in the cage silsesquioxane group in the polymer (A) is an aromatic group. The polymer (A) is obtained by reacting a compound (M) having a caged silsesquioxane group represented by the following formula (1 '). Thermosetting resin composition.
[RSiO _3/2 ] _n [YSiO _3/2 ] _m (1 ′)
(In the formula (1 ′), R represents an organic group having 1 to 10 carbon atoms, Y represents a functional group that can be a binding site with the main chain or side chain of the polymer (A), and n represents 4 to 7). M represents an integer of 1 to 4, and n + m = 8.) The said compound (M) is represented by following formula (2 '), The thermosetting resin composition of Claim 6 characterized by the above-mentioned.

(In the formula (2 ′), R represents an organic group having 1 to 10 carbon atoms, and Y represents a functional group that can be a bonding site with the main chain of the polymer (A).)   The thermosetting resin composition according to claim 6 or 7, wherein the substituent R contained in the cage silsesquioxane group in the polymer (A) is an aromatic group.   The thermosetting resin composition according to any one of claims 1 to 8, wherein the thermosetting resin (B) is an epoxy resin.   The thermosetting resin composition according to any one of claims 1 to 9, wherein the thermosetting resin (B) is a glycidyl ether type epoxy resin.   The electronic device containing the thermosetting resin composition as described in any one of Claims 1-10.

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