JP2023063072A - Method for producing cured product - Google Patents

Abstract

To provide a method for producing a cured product having a high curing rate and improved safety.SOLUTION: The method for producing a cured product according to one embodiment of the present invention includes a curing step of heating a curable composition at a temperature range of 40-180°C, the curable composition containing: a (meth)acrylic polymer (A) having 1.0 or more hydrolyzable silyl groups at or near a molecular terminal per molecule on average; and a thermal base generator (B) or a phosphate-containing thermal acid generator (C).SELECTED DRAWING: None

Description

The present invention relates to a method for producing a cured product.

Conventionally, adhesives and the like using polymers having hydrolyzable silyl groups have been developed (for example, Patent Documents 1 and 2). Further, a technique for curing such a polymer having a hydrolyzable silyl group in a short time includes heat curing. For example, Patent Document 3 describes a heat curing method using an organic tin compound.

WO2006/051798 JP 2011-84750 A WO2019/189664

However, the conventional techniques as described above have room for improvement from the viewpoint of curing speed or safety.

An object of one aspect of the present invention is to provide a method for producing a cured product having a high curing rate and improved safety.

In order to solve the above problems, the method for producing a cured product according to one aspect of the present invention has an average of 1.0 or more hydrolyzable silyl groups per molecule at or near the end of the molecule ( Curing by heating a curable composition containing a meth)acrylic polymer (A) and a thermal base generator (B) or a phosphate-containing thermal acid generator (C) in a temperature range of 40 to 180 ° C. have a process.

In addition, the curable composition according to one aspect of the present invention is a (meth)acrylic polymer (A ), and a thermal base generator (B) or a phosphate-containing thermal acid generator (C), to be cured by heating at 40 to 180° C. for use.

According to one aspect of the present invention, it is possible to provide a cured product with improved safety because it has a high curing speed and does not require the use of, for example, an organic tin compound.

Examples of embodiments of the present invention will be described in detail below, but the present invention is not limited to these. Unless otherwise specified in this specification, "A to B" representing a numerical range means "A or more and B or less". As used herein, "(meth)acryl" means "acryl" and/or "methacryl".

[1. Method for producing cured product]
The method for producing a cured product according to one aspect of the present invention (hereinafter also referred to as the present production method) has an average of 1.0 or more hydrolyzable silyl groups per molecule at or near the end of the molecule ( Curing by heating a curable composition containing a meth)acrylic polymer (A) and a thermal base generator (B) or a phosphate-containing thermal acid generator (C) in a temperature range of 40 to 180 ° C. have a process.

Since the techniques described in Patent Literatures 1 and 2 as described above involve hydrolysis reaction, there is a problem that the curing time is long. Moreover, since the technique described in Patent Document 3 uses an organic tin-based compound, there is room for improvement from the viewpoint of safety.

In this production method, a thermal base generator (B) substantially free of tin or a phosphate-containing thermal acid generator (C) is used as a condensation catalyst for the (meth)acrylic polymer (A). Available. Therefore, a cured product can be produced by curing the curable composition by heating in a short time without using an organic tin compound as a catalyst.

(Curing process)
The heating temperature in the curing step is 40 to 180°C, preferably 50 to 160°C, more preferably 60 to 150°C, still more preferably 70 to 140°C. When the heating temperature is 40° C. or higher, the curable composition can be easily cured in a short time. Also, if the heating temperature is 180° C. or lower, the (meth)acrylic polymer (A) is less likely to be thermally decomposed.

The heating time in the curing step is preferably 1 to 60 minutes, more preferably 5 to 50 minutes, still more preferably 10 to 30 minutes. If the heating time is within the above range, it can be said that the cured product has sufficient strength and the time required for curing is short.

Each component contained in the curable composition will be described in detail below.

<1-1. (Meth) acrylic polymer (A)>
The (meth)acrylic polymer (A) has an average of 1.0 or more hydrolyzable silyl groups per molecule at or near the terminal of the molecule. "Near the end of the molecule" means, for example, that 40% or less, 30% or less, or 25% or less of the repeating units counted from the end of the molecule are located, with the total number of repeating units contained in the molecule being 100%. can be a region. Since a linear molecule has two ends, it also has two near ends.

In one embodiment, the (meth)acrylic polymer (A) has a hydrolyzable silyl group at at least one end of the molecule. Therefore, the molecule as a whole has one or two hydrolyzable silyl groups. Such a polymer can be produced, for example, by the first aspect of the production methods described below.

In one embodiment, the (meth)acrylic polymer (A) has a hydrolyzable silyl group near at least one end of the molecule. One or more hydrolyzable silyl groups can be present in one proximal region. Thus, the molecule as a whole has one or more hydrolyzable silyl groups and can have more than two hydrolyzable silyl groups. Such a polymer can be produced, for example, by the second aspect of the below-described production method. According to this production method, a (meth)acrylic polymer (A1), which will be described later, is obtained.

In one embodiment, the (meth)acrylic polymer (A) has hydrolyzable silyl groups near both ends of the molecule. One or more hydrolyzable silyl groups can be present in one proximal region. Thus, the molecule as a whole has two or more hydrolyzable silyl groups and can have more than two hydrolyzable silyl groups. Such a polymer can be produced, for example, by the second aspect of the below-described production method. According to this production method, a (meth)acrylic polymer (A1), which will be described later, is obtained.

In one embodiment, the (meth)acrylic polymer (A) has hydrolyzable silyl groups both in the vicinity of at least one terminal of the molecule and in a region other than the vicinity of the terminal of the molecule. In one embodiment, the (meth)acrylic polymer (A) has a hydrolyzable silyl group at at least one end of the molecule, and has a hydrolyzable silyl group in a region other than the end of the molecule. not.

In the above description, the term “vicinity of the terminal” may be the X block of the (meth)acrylic polymer (A1) described below.

The average number of hydrolyzable silyl groups introduced into the (meth)acrylic polymer (A) is 1.0 or more for the entire molecule. In one embodiment, the average number of hydrolyzable silyl groups introduced into the (meth)acrylic polymer (A) is more than 1.0 for the entire molecule. In one embodiment, the number of hydrolyzable silyl groups is preferably 1.1 or more, more preferably 1.2 or more. In another embodiment, the number of hydrolyzable silyl groups is preferably 2.2 or more, more preferably 2.4 or more. The upper limit of the number of hydrolyzable silyl groups introduced into the (meth)acrylic polymer (A) is preferably 10.0 or less, more preferably 8.0 or less, and further preferably 6.0 or less. preferable. If the number of hydrolyzable silyl groups is within the above range, the physical properties of the curable composition and the cured product using the (meth)acrylic polymer (A) will be good. The (meth)acrylic polymer (A) preferably has hydrolyzable silyl groups at both ends (or terminal regions) of the molecule.

A (meth)acrylic polymer (A) according to one embodiment of the present invention contains a repeating unit derived from a (meth)acrylate monomer. The (meth)acrylic acid ester monomer used as the raw material of the (meth)acrylic polymer (A) is not particularly limited. Only one type of (meth)acrylic acid ester monomer may be used, or two or more types of (meth)acrylic acid ester monomers may be used in combination.

The types of such (meth)acrylic acid ester monomers include the following.
- (Meth)acrylic acid ester monomer (α): having an alkyl group ester-bonded to (meth)acrylic acid, and the alkyl group having an alkoxy group having 1 to 5 carbon atoms; There are monomers. The number of carbon atoms in the alkyl group is preferably 1-5, more preferably 1-3, and particularly preferably 2. The number of carbon atoms in the alkoxy group is preferably 1-3, more preferably 1-2, and particularly preferably 1.
(Meth)acrylic acid ester monomer (β): a monomer having 1 to 5 carbon atoms in the alkyl group ester-bonded to (meth)acrylic acid.
(Meth)acrylic acid ester monomer (γ): a monomer in which the alkyl group ester-bonded to (meth)acrylic acid has 6 to 15 carbon atoms.
(Meth)acrylic acid ester monomer (δ): a monomer having 16 to 25 carbon atoms in the alkyl group ester-bonded to (meth)acrylic acid.

In one embodiment, the preferred monomer composition of the (meth)acrylic polymer (A) is as follows. The ratios below are based on the weight of all repeating units contained in the (meth)acrylic polymer (A). With such a monomer composition, the (meth)acrylic polymer (A) can obtain good workability, mechanical properties and weather resistance.
(Meth)acrylate monomer (α)-derived repeating unit: 0 to 20% by weight is preferred.
- Total of repeating units derived from (meth)acrylic acid ester monomer (β) and (meth)acrylic acid monomer (γ): 45 to 96% by weight is preferable.
(Meth)acrylate monomer (δ)-derived repeating unit: preferably 4 to 35% by weight.

In one embodiment, the preferred monomer composition of the (meth)acrylic polymer (A) is as follows. The ratios below are based on the weight of all repeating units contained in the (meth)acrylic polymer (A). With such a monomer composition, the viscosity of the (meth)acrylic polymer (A) can be further reduced, resulting in further improved workability.
(Meth)acrylate monomer (α)-derived repeating unit: preferably 5 to 20% by weight, more preferably 10 to 20% by weight.
(Meth)acrylate monomer (β)-derived repeating unit: preferably 45 to 70% by weight, more preferably 50 to 70% by weight.
(Meth)acrylate monomer (γ)-derived repeating unit: preferably 0 to 25% by weight, more preferably 10 to 25% by weight.
(Meth)acrylate monomer (δ)-derived repeating unit: preferably 15 to 25% by weight, more preferably 15 to 20% by weight.

If the content of the repeating unit derived from the (meth)acrylic acid ester monomer (β) is within the above range, a curable composition with low viscosity and good workability can be obtained. If the content of repeating units derived from the (meth)acrylic acid ester monomer (γ) is within the above range, a cured product with excellent durability can be obtained. If the content of repeating units derived from the (meth)acrylic acid ester monomer (δ) is within the above range, a cured product having excellent mechanical properties can be obtained.

The (meth)acrylic acid ester monomer is not particularly limited, and conventionally known ones can be used. Examples of (meth)acrylic acid ester monomers (α) include 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-butoxyethyl (meth)acrylate, and (meth)acrylic acid. Isopropoxyethyl can be mentioned. Examples of (meth)acrylate monomers (β) include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, and (meth)acryl. Examples include isobutyl acid and tert-butyl (meth)acrylate. Examples of (meth)acrylate monomers (γ) include n-hexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, and (meth)acrylate. nonyl acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, and tetradecyl (meth)acrylate. Examples of (meth)acrylate monomers (δ) include pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, octadecyl (meth)acrylate, icosyl (meth)acrylate, Docosyl (meth)acrylate can be mentioned.

Among the monomers described above, 2-methoxyethyl acrylate is preferred as the (meth)acrylate monomer (α). As the (meth)acrylic acid ester monomer (β), n-butyl acrylate is preferred. As the (meth)acrylic ester monomer (γ), 2-ethylhexyl acrylate and dodecyl acrylate are preferred. Octadecyl acrylate is preferred as the (meth)acrylic acid ester monomer (δ). By selecting these monomers, the produced (meth)acrylic polymer (A) can achieve high levels of viscosity, weather resistance, mechanical properties, and durability in a well-balanced manner.

In one embodiment, the (meth)acrylate monomer (α) is (a) and/or (b) below.

(a) A monomer having 1 to 5 carbon atoms in the alkyl group ester-bonded to (meth)acrylic acid. However, "the number of carbon atoms in the alkyl group" does not include the carbon atoms contained in the alkoxy group of the alkyl group.

(b) one or more selected from the group consisting of 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-butoxyethyl (meth)acrylate, and isopropoxyethyl (meth)acrylate of monomers.

The repeating unit derived from the (meth)acrylic acid ester monomer contained in the (meth)acrylic polymer (A) is 70% by weight or more based on all the repeating units contained in the polymer (A). is preferred, and 90% by weight or more is more preferred. If the content of repeating units derived from the (meth)acrylate monomer is 70% or more, the produced (meth)acrylic polymer (A) will have good weather resistance, mechanical properties and durability. .

In one embodiment, the (meth)acrylic polymer (A) has repeating units derived from n-butyl acrylate. The content of repeating units derived from n-butyl acrylate is preferably 50% by weight or more, and 70% by weight or more, based on the weight of all repeating units contained in the (meth)acrylic polymer (A). is more preferable, and 90% by weight or more is even more preferable. By using such a (meth)acrylic polymer (A), a curable composition with low viscosity and good workability can be obtained.

In one embodiment, the (meth)acrylic polymer (A) preferably has a number average molecular weight of 4,000 to 80,000, more preferably 10,000 to 50,000. If the number average molecular weight is 4,000 or more, the properties of the (meth)acrylic polymer (A) can be fully exhibited. If the number average molecular weight is 80,000 or less, the viscosity does not become too high and sufficient workability can be ensured.

The (meth)acrylic polymer (A) preferably has a molecular weight distribution (Mw/Mn) of 1.8 or less, hereinafter 1.7 or less, 1.6 or less, 1.5 or less, It becomes preferable in order of 4 or less and 1.3 or less. If the molecular weight distribution is within the above range, a curable composition with low viscosity and good workability can be obtained.

The weight average molecular weight and number average molecular weight can be measured, for example, by gel permeation chromatography (GPC). For GPC measurement, chloroform can be used as a mobile phase and a polystyrene gel column can be used as a stationary phase. Moreover, these molecular weights can be calculated in terms of polystyrene.

The (meth)acrylic polymer (A) having such a narrow molecular weight distribution can be suitably produced by, for example, living radical polymerization.

(Hydrolyzable silyl group)
In one embodiment, the hydrolyzable silyl group is represented by general formula (1) below. Two or more types of hydrolyzable silyl groups represented by general formula (1) may be contained in one molecule of the (meth)acrylic polymer (A).
—[Si(R ¹ ) _2-b (Y) _b O] _m —Si(R ² ) _3-a (Y) _a (1)
In the formula, R ¹ and R ² are independently an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or (R') ₃ SiO— (At this time, R' is a monovalent hydrocarbon group having 1 to 20 carbon atoms, and the three R's present may be the same or different). When two or more R ¹ or R ² are present in one hydrolyzable silyl group, the structures of the R ¹ or R ² may be the same or different.

Y is an alkoxy group having 1 to 20 carbon atoms. When two or more Y are present in one hydrolyzable silyl group, the Y may be the same or different. a is 0, 1, 2 or 3; b is 0, 1 or 2; m is an integer from 0 to 19; However, it satisfies the relationship a+mb≧1.

In one embodiment, the hydrolyzable silyl group is represented by general formula (2) below. Two or more types of hydrolyzable silyl groups represented by general formula (2) may be contained in one molecule of the (meth)acrylic polymer (A).
—Si(R ² ) _3-a (Y) _a (2)
In the formula, the definitions of R ² and Y are as described above. a is 1, 2 or 3;

In general, alkoxy groups with fewer carbon atoms have higher reactivity. That is, the reactivity decreases in the order of methoxy group, ethoxy group, and propoxy group. Using this property, the specific structure of the hydrolyzable silyl group can be appropriately determined according to the production method and application of the (meth)acrylic polymer (A). A known method may be employed for introducing a hydrolyzable silyl group into the main chain of the (meth)acrylic polymer (A).

Specific examples of hydrolyzable silyl groups include dimethoxysilyl group, trimethoxysilyl group, diethoxysilyl group, triethoxysilyl group, triisopropoxysilyl group, dimethoxymethylsilyl group, diethoxymethylsilyl group, diisopropoxy A methylsilyl group is mentioned. Among them, from the viewpoint of curability of the curable composition, dimethoxymethylsilyl group, dimethoxymethylsilyl group, trimethoxysilyl group, triethoxysilyl group and the like are preferable, and dimethoxymethylsilyl group is particularly preferable.

((Meth) acrylic polymer (A1))
In one embodiment, the (meth)acrylic polymer (A) has an X block and a Y block, and contains an XY diblock structure or an XYX triblock structure in the molecule. An X block is a block having a relatively high content of hydrolyzable silyl groups. A Y block is a Y block having a relatively low content of hydrolyzable silyl groups. Such a (meth)acrylic polymer is referred to herein as a (meth)acrylic polymer (A1). The structure of the entire molecule of the (meth)acrylic polymer (A1) is not particularly limited as long as it contains an XY diblock structure or an XYX triblock structure, and may be, for example, an XYXY tetrablock structure.

Here, the "XYX triblock structure" means the "ABA triblock structure" generally called by those skilled in the art. The ratio of X/Y in the XY diblock structure and the XYX triblock structure is preferably (5/95) to (60/40), more preferably (15/85) to (40/60). The X block may be a region in which 40% or less, 30% or less, or 25% or less of the repeating units counted from the end of the molecule are located, with the total number of repeating units contained in the molecule being 100%.

In one embodiment, the (meth)acrylic polymer (A1) has a repeating unit derived from a (meth)acrylate monomer having a hydrolyzable silyl group. A relatively large amount of repeating units derived from the (meth)acrylic acid ester monomer having this hydrolyzable silyl group is contained in the X block. Specifically, the number of repeating units derived from a (meth)acrylic acid ester monomer having a hydrolyzable silyl group contained in the X block is 1.0 or more on average. On the other hand, the repeating unit derived from a (meth)acrylate monomer having a hydrolyzable silyl group contained in the Y block is 0 to 3 weights based on the weight of all repeating units contained in the Y block. %. Therefore, the repeating unit derived from the (meth)acrylic acid ester monomer having a hydrolyzable silyl group is localized near the end of the (meth)acrylic polymer (A1).

The average number of repeating units derived from (meth)acrylic acid ester monomers having a hydrolyzable silyl group contained in the X block is preferably 1.5 or more, more preferably 1.7 or more. Similarly, the repeating unit derived from the (meth)acrylic acid ester monomer having a hydrolyzable silyl group contained in the X block is greater than 3% by weight based on the weight of all repeating units contained in the X block. is preferred, 4.5% by weight or more is more preferred, and 5% by weight or more is even more preferred. The upper limit of the repeating unit derived from the (meth) acrylic acid ester monomer having a hydrolyzable silyl group contained in the Y block is 2% by weight based on the weight of all repeating units contained in the Y block. The following are preferable, and 1% by weight or less is more preferable. The lower limit of the repeating unit derived from the (meth) acrylic acid ester monomer having a hydrolyzable silyl group contained in the Y block is 0% by weight based on the weight of all repeating units contained in the Y block. More than is preferred, and 0% by weight or more is more preferred.

[Method for producing (meth)acrylic polymer (A)]
The polymerization method of the (meth)acrylic polymer (A) is not particularly limited, and known polymerization methods can be used (radical polymerization method, cationic polymerization method, anionic polymerization method, etc.). Among them, the living polymerization method is preferable because a functional group can be introduced at the end of the polymer molecule and an XY block polymer or an XYX block polymer can be synthesized. Examples of living polymerization methods include living radical polymerization methods, living cationic polymerization methods, and living anionic polymerization methods, among which living radical polymerization methods are suitable for polymerization of acrylic acid ester monomers. Examples of living radical polymerization methods include the following.
Atom Transfer Radical Polymerization (ATRP (see J. Am. Chem. Soc. 1995, 117, 5614; Macromolecules. 1995, 28, 1721))
・Single Electron Transfer Polymerization (SET-LRP (see J. Am. Chem. Soc. 2006, 128, 14156; JPSChem 2007, 45, 1607))
・Reversible Chain Transfer Catalyzed Polymerization (RTCP)
・Reversible addition-fragmentation chain transfer polymerization (RAFT polymerization)
・Nitrooxy radical method (NMP method)
・Polymerization method using organic tellurium compound (TERP) method ・Polymerization method using organic antimony compound (SBRP method)
・Polymerization method using organic bismuth compounds (BIRP)
Iodine transfer polymerization method Among living radical polymerizations, atom transfer radical polymerization is preferred because it is easy to introduce a (meth)acryloyl group to the terminal of the polymer.

Preferred embodiments of the method for producing the (meth)acrylic polymer (A) are described below. In addition, the descriptions in JP-A-2005-232419, JP-A-2006-291073, etc. can be referred to.

(General Matters Concerning Living Radical Polymerization)
Among living radical polymerizations, atom transfer radical polymerization, one-electron transfer polymerization, and reverse transfer catalyst polymerization are preferred. A more preferable production method is a living radical polymerization method of a vinyl-based monomer using ATRP or SET-LRP and using a transition metal or a transition metal complex (consisting of a transition metal compound and a ligand) as a catalyst. be able to. Furthermore, RTCP that does not use transition metals as a catalyst is also included.

There are currently two interpretations of the mechanism of transition metal complex-catalyzed living radical polymerization: ATRP and SET-LRP. Interpreted on the basis of ATRP, a living radical polymerization consists of an equilibrium of the following two reactions (illustrated using a copper complex as an example).
(a) A monovalent copper complex generates a radical by abstracting a halogen from a terminal of a polymer to form a divalent copper complex.
(b) The bivalent copper complex becomes a monovalent copper complex by adding a halogen to the radical at the polymerization terminal.

On the other hand, interpreted on the basis of SET-LRP, living radical polymerization consists of the equilibrium of the following three reactions (illustrated using a copper complex as an example):
(a) Zero-valent metal copper or a copper complex is converted into a divalent copper complex by abstracting the halogen at the terminal of the polymer to generate a radical.
(b) A bivalent copper complex becomes a zero valent copper complex by adding a halogen to the radical at the polymerization terminal.
(c) The monovalent copper complex is disproportionated into zero and divalent copper complexes.

Although the manufacturing methods described herein can be interpreted as either living radical polymerization system, no particular distinction is made between the two herein. Any living radical polymerization system using a transition metal or transition metal compound as a catalyst and a ligand is included in the scope of the present invention.

In addition, Activators Regenerated by Electron Transfer: ARGET, which is an improved ATRP synthesis method, has also been reported (Macromolecules. 2006, 39, 39). In this method, a reducing agent is used to reduce the highly oxidized transition metal complex that causes the polymerization to be delayed or stopped, so that the polymerization reaction proceeds rapidly to a high reaction rate even under low catalyst conditions with little transition metal complex. can be made This ARGET can also be employed in the present invention.

Various agents that can be used in the manufacturing method according to one embodiment of the present invention are individually described below. All of these agents may be used alone or in combination of two or more. Further, these agents themselves may be put into the polymerization system, or these agents may be generated in the polymerization system.

(a. Initiator)
In order to obtain a (meth)acrylic polymer (A) having a hydrolyzable silyl group at the end of the molecule (that is, in the first aspect described later), two or more initiation points are used as the initiator. It is preferred to use organic halides or sulfonyl halide compounds having Specific examples include compounds represented by the following formulas.

One example is diethyl-2,5-dibromoadipate.

Further, in order to obtain the (meth)acrylic polymer (A1) (that is, in the second aspect described later), a radical initiator having one halogen group in the molecule is used as the initiator. be able to. Examples of such initiators include ethyl 2-bromoisobutyrate, ethyl 2-bromobutyrate, ethyl bromoacetate, methyl bromoacetate, (1-bromoethyl)benzene, allyl bromide, methyl 2-bromopropionate, methyl chloroacetate. , methyl 2-chloropropionate, and (1-chloroethyl)benzene.

An initiator having a hydrolyzable silyl group may also be used as the initiator. Alternatively, a hydrolyzable silyl group may be introduced into the initiator before or after the polymerization reaction. A (meth)allyl-based polymer (A) having at least a hydrolyzable silyl group at the terminal can also be produced by such a method.

(b. Polymerization catalyst)
In the ATRP system, whether a reducing agent is used or not, a metal complex having an element of Groups 7, 8, 9, 10 or 11 of the periodic table as the central metal can be used. . Among them, metal complexes having monovalent copper, divalent ruthenium, and divalent iron as central metals are particularly suitable.

Specific examples include cuprous chloride, cuprous bromide, cuprous iodide, cuprous cyanide, cuprous oxide, cuprous acetate, and cuprous perchlorate. When using a copper compound as a polymerization catalyst, it is preferable to add an amine ligand to the polymerization system in order to increase the catalytic activity. A divalent ruthenium chloride tristriphenylphosphine complex (RuCl ₂ (PPh ₃ ) ₃ ) is also suitable as a catalyst. When using this catalyst, it is preferable to add an aluminum compound (such as trialkoxyaluminum) to the polymerization system in order to increase the catalytic activity. Furthermore, a tristriphenylphosphine complex of divalent iron chloride (FeCl ₂ (PPh ₃ ) ₃ ) is also suitable as a catalyst.

Among the above, the copper catalyst is inexpensive and preferable. It is more preferable to use a polydentate amine and a copper catalyst in combination in order to enhance catalytic activity and productivity.

(c. Polydentate amine)
Examples of polydentate amines that can be used as ligands include:
- Bidentate polydentate amines: 2,2-bipyridine, 4,4'-di-(5-nonyl)-2,2'-bipyridine, N-(n-propyl)pyridylmethanimine, N-( n-octyl)pyridylmethanimine tridentate polydentate amine: N,N,N',N'',N''-pentamethyldiethylenetriamine, N-propyl-N,N-di(2-pyridylmethyl) ) amines and tetradentate polydentate amines: hexamethyltris(2-aminoethyl)amine (Me ₆ TREN), N,N-bis(2-dimethylaminoethyl)-N,N'-dimethylethylenediamine, 2, 5,9,12-tetramethyl-2,5,9,12-tetraazatetradecane, 2,6,9,13-tetramethyl-2,6,9,13-tetraazatetradecane, 4,11-dimethyl- 1,4,8,11-tetraazabicyclohexadecane, N′,N″-dimethyl-N′,N″-bis((pyridin-2-yl)methyl)ethane-1,2-diamine, tris[ (2-pyridyl)methyl]amine, 2,5,8,12-tetramethyl-2,5,8,12-tetraazatetradecane/pentadentate polydentate amine: N,N,N',N'',N''',N'''',N''''-heptamethyltetraethylenetetramine/hexadentate multidentate amine: N,N,N',N'-tetrakis(2-pyridylmethyl ) Ethylenediamine/polyamine: polyethyleneimine.

(d. Base)
A base may be added to the polymerization system to neutralize any acid present or generated in the polymerization system and to prevent acid accumulation. Examples of bases include:
- Monoamine: A monoamine refers to a compound having one site per molecule that acts as a base. Examples of monoamines include primary amines (methylamine, aniline, lysine, etc.), secondary amines (dimethylamine, piperidine, etc.), tertiary amines (trimethylamine, triethylamine, etc.), aromatic amines (pyridine, pyrrole, etc.), Ammonia is mentioned.
Polyamines: Examples of polyamines include diamines (ethylenediamine, tetramethylethylenediamine, etc.), triamines (diethylenetriamine, pentamethyldiethylenetriamine, etc.), tetramines (triethylenetetramine, hexamethyltriethylenetetramine, hexamethylenetetramine, etc.), polyethyleneimines, etc. is mentioned.
- Inorganic base: An inorganic base refers to an element or compound of an element belonging to Groups 1 and 2 of the periodic table. Examples of elemental elements belonging to groups 1 and 2 of the periodic table include lithium, sodium, and calcium. Examples of compounds of elements belonging to groups 1 and 2 of the periodic table include sodium methoxide, potassium ethoxide, methyllithium, sodium hydroxide, potassium hydroxide, potassium carbonate, sodium hydrogen carbonate, ammonium hydrogen carbonate, phosphoric acid Trisodium, disodium hydrogen phosphate, tripotassium phosphate, dipotassium hydrogen phosphate, sodium acetate, potassium acetate, sodium oxalate, potassium oxalate, sodium phenoxy, potassium phenoxy, sodium ascorbate, potassium ascorbate. .

(e. Reducing agent)
In living radical polymerization using a copper complex as a catalyst, it is known that the combined use of a reducing agent improves the polymerization activity (ARGET ATRP). In ARGET ATRP, it is believed that polymerization activity is improved by reducing and reducing highly oxidized transition metal complexes (generated by coupling between radicals) that cause delay or termination of the polymerization reaction. As a result, it is possible to reduce the amount of the transition metal catalyst, which is usually required from several hundred to several thousand ppm, to several tens to several hundred ppm. In one embodiment of the present invention, the manufacturing method can use a reducing agent to achieve a reaction mechanism similar to ARGET ATRP. Examples of reducing agents include:

(Reducing agent that does not generate acid when reducing copper complex)
・Metals: Examples of metals include alkali metals (lithium, sodium, potassium, etc.), alkaline earth metals (beryllium, magnesium, calcium, barium, etc.), typical metals (aluminum, zinc, etc.), transition metals (copper, nickel) , ruthenium, iron, etc.). These metals can also be used in the form of alloys (amalgams) with mercury.
- Metal compound: Examples of metal compounds include metal salts and metal complexes. Examples of ligands coordinated to the metal complex include carbon monoxide, olefins, nitrogen-containing compounds, oxygen-containing compounds, phosphorus-containing compounds, and sulfur-containing compounds. More specific examples include compounds of metals and ammonia/amines, titanium trichloride, titanium alkoxide, chromium chloride, chromium sulfate, chromium acetate, iron chloride, copper chloride, copper bromide, tin chloride, zinc acetate, water Zinc oxide, carbonyl complexes (Ni(CO) ₄ , _{Co2CO8 ,} etc.), olefin complexes ([Ni(cod) ₂ ], [ _RuCl2 (cod)], [ _PtCl2 (cod)], etc.; cod is cyclo representing octadiene), phosphine complexes ([RhCl(P( _{C6H5 ) 3} ) ₃ ], [ _RuCl2 ( _P ( _{C6H5 ) 3} ) ₂ ], [ _PtCl2 (P( _C6H5 ) ₃ ) ₂ ], etc.).
Organotin compounds: Specific examples include tin octylate, tin 2-ethylhexylate, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin mercaptide, dibutyltin thiocarboxylate, dibutyltin dimaleate, and dioctyltin thiocarboxylate.
Phosphorus or a phosphorus compound: Specific examples include phosphorus, trimethylphosphine, triethylphosphine, triphenylphosphine, trimethylphosphite, triethylphosphite, triphenylphosphite, hexamethylphosphorustriamide, and hexaethylphosphorustriamide. mentioned.
- Sulfur or sulfur compounds: Specific examples include sulfur, Rongalites, hydrosulfites, and thiourea dioxide. Rongalite refers to a formaldehyde derivative of a sulfoxylate, represented by the general formula: MSO ₂ ·CH ₂ O (wherein M is Na or Zn). Specific examples of Rongalite include sodium formaldehyde sulfoxylate and zinc formaldehyde sulfoxylate. Hydrosulfite refers to sodium hyposulfite and formaldehyde derivatives of sodium hyposulfite.

(Reducing agent (hydride reducing agent) that generates an acid when reducing a copper complex)
Metal hydride: specific examples include sodium hydride, germanium hydride, tungsten hydride, aluminum hydride (diisobutylaluminum hydride, lithium aluminum hydride, sodium aluminum hydride, sodium triethoxyaluminum hydride, bis(2-methoxyethoxy)aluminum sodium, etc.), organotin hydrides (triphenyltin hydride, tri-n-butyltin hydride, diphenyltin hydride, di-n-butyltin hydride, triethyltin hydride, trimethyltin, etc.).
Silicon hydrides: Specific examples include trichlorosilane, trimethylsilane, triethylsilane, diphenylsilane, phenylsilane, and polymethylhydrosiloxane.
-Borohydride: specific examples include borane, diborane, sodium borohydride, sodium trimethoxyborohydride, sodium borohydride sulfide, sodium borohydride cyanide, lithium borohydride cyanide, lithium borohydride, hydride Lithium triethylborohydride, lithium tri-s-butylborohydride, lithium tri-t-butylborohydride, calcium borohydride, potassium borohydride, zinc borohydride, tetra-n-butylammonium borohydride. be done.
- Nitrogen hydrogen compound: Specific examples include hydrazine and diimide.
• Phosphorus or a phosphorus compound: Specific examples include phosphine and diazaphosphorene.
• Sulfur or a sulfur compound: Specific examples include hydrogen sulfide.
- Organic compounds exhibiting a reducing action: Specific examples include alcohols, aldehydes, phenols, and organic acid compounds. Examples of alcohols include methanol, ethanol, propanol, isopropanol. Examples of aldehydes include formaldehyde, acetaldehyde, benzaldehyde, formic acid. Examples of phenols include phenol, hydroquinone, dibutylhydroxytoluene and tocopherol. Examples of organic acid compounds include citric acid, oxalic acid, ascorbic acid, ascorbates, and ascorbic acid esters.

Alternatively, the reducing agent may be generated in the polymerization system by electrolytic reduction. In electrolytic reduction, electrons generated at the cathode directly (or after solvation) exhibit a reducing action. That is, the reducing agent may be generated by electrolysis.

(f. solvent)
Examples of solvents include: However, ATRP can also be carried out under conditions in which no solvent is used.
・Highly polar aprotic solvents: dimethyl sulfoxide (DMSO), dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N-methylpyrrolidone・carbonate solvents: ethylene carbonate, propylene carbonate・alcoholic solvents: methanol , ethanol, propanol, isopropanol, n-butyl alcohol, tert-butyl alcohol/nitrile solvents: acetonitrile, propionitrile, benzonitrile/ketone solvents: acetone, methyl ethyl ketone, methyl isobutyl ketone/ether solvents: diethyl ether, tetrahydrofuran・Halogenated hydrocarbon solvents: methylene chloride, chloroform ・Ester solvents: ethyl acetate, butyl acetate ・Hydrocarbon solvents: pentane, hexane, heptane, cyclohexane, octane, decane, benzene, toluene, xylene ・Other solvents: ions liquids, water, supercritical fluids.

In the ATRP (ARGET) system using a reducing agent, the uniformity of the transition metal or transition metal compound, polydentate amine, base, reducing agent, monomer and initiator in the polymerization system is essential for reaction control and polymerization reaction. Preferred in terms of speed, ease of preparation and scale-up risk. Therefore, it is preferable to select a solvent that can dissolve these substances.

Two examples will be given below to describe a more specific method for producing the (meth)acrylic polymer (A). Among these examples, according to the second aspect, the (meth)acrylic polymer (A1) can be produced.

(First aspect)
In one example, the (meth)acrylic polymer (A) is produced by the method described in JP-A-2007-302749. Among them, the method of adding a hydrosilane compound having a hydrolyzable silyl group to a (meth)acrylic polymer having at least one alkenyl group in the presence of a hydrosilylation catalyst is easier to control. preferable.

In this method, a hydrolyzable silyl group is introduced into a (meth)acrylic polymer as follows.
1. A (meth)acrylic acid ester monomer is subjected to living radical polymerization to obtain a (meth)acrylic polymer.
The (meth)acrylic polymer obtained in 2.1 is reacted with a compound (diene compound) having at least two alkenyl groups with low polymerizability to obtain a vinyl polymer having at least one alkenyl group.
A hydrosilane compound having a hydrolyzable silyl group is added to the vinyl polymer obtained in 3.2 in the presence of a hydrosilylation catalyst.

More specifically, the above-mentioned step 2 is the production of a (meth)acrylic polymer by living radical polymerization, in which a diene compound (1,5-hexadiene, 1, 7-octadiene, 1,9-decadiene, etc.).

A hydrosilane compound having a hydrolyzable silyl group is not particularly limited. A representative example is the compound represented by the general formula (3).
H—[Si(R ¹ ) _2-b (Y) _b O] _m —Si(R ² ) _3-a (Y) _a (3)
In general formula (3), definitions of R ¹ , R ² , Y, a, b, and m are the same as in general formula (1).

Among these hydrosilane compounds, compounds represented by the following general formula (4) are preferable from the standpoint of easy availability.
H—Si(R ² ) _3-a (Y) _a (4)
In general formula (4), definitions of R ² , Y and a are the same as in general formula (1).

Examples include methyldimethoxysilane, trimethoxysilane, triethoxysilane, and the like.

A transition metal catalyst is usually used to add a hydrosilane compound having a hydrolyzable silyl group to an alkenyl group. Examples of transition metal catalysts include platinum-based catalysts. More specifically, platinum simple substance; platinum solid dispersed in a carrier (alumina, silica, carbon black, etc.); chloroplatinic acid; complexes of chloroplatinic acid and alcohols, aldehydes, ketones, etc.; platinum-olefin complexes a platinum (0)-divinyltetramethyldisiloxane complex; Examples of catalysts other than platinum- _based catalysts include RhCl( _PPh3 ) ₃ , _RhCl3 , _RuCl3 , _IrCl3 , _FeCl3 , _AlCl3 , _PdCl2.H2O , _NiCl2 , and _TiCl4 .

(Second aspect)
In one embodiment, the (meth)acrylic polymer (A) can be produced by a production method including the following Steps 1a and 2a, or the following Steps 1b and 2b. Since a block copolymer is produced in this production method, the (meth)acrylic polymer (A) obtained is the (meth)acrylic polymer (A1). The (meth)acrylic polymer (A1) obtained by this production method is preferable in that the viscosity of the polymer is lowered.

In the following description, "containing 0% by weight of a (meth)acrylic acid ester monomer having a hydrolyzable silyl group" means "not containing a (meth)acrylic acid ester monomer having a hydrolyzable silyl group". means that

(Step 1a) A step of polymerizing a (meth)acrylic acid ester monomer mixture containing (preferably more than 3% by weight) a (meth)acrylic acid ester monomer having a hydrolyzable silyl group with a living polymerization initiator.

(Step 2a) A step of adding a (meth)acrylic acid ester monomer mixture containing 0 to 3% by weight of a (meth)acrylic acid ester monomer having a hydrolyzable silyl group to the reaction system after the step 1a for polymerization.

(Step 1b) A step of polymerizing a (meth)acrylic acid ester monomer mixture containing 0 to 3% by weight of a (meth)acrylic acid ester monomer having a hydrolyzable silyl group with a living polymerization initiator.

(Step 2b) Add a (meth)acrylic acid ester monomer mixture containing (preferably more than 3% by weight) a (meth)acrylic acid ester monomer having a hydrolyzable silyl group to the reaction system after the step 1b, and polymerize. The process of making

Hereinafter, each step will be described more specifically for each structure of the (meth)acrylic polymer (A1).

(When the polymer has an XY diblock structure)
The (meth)acrylic polymer (A1), which is a molecule with an XY diblock structure, can be produced by the above-described steps 1a and 2a, or by steps 1b and 2b. At this time, the X block containing relatively many hydrolyzable silyl groups is formed by the steps 1a and 2b. On the other hand, the Y block containing relatively few hydrolyzable silyl groups is formed by steps 2a and 1b.

In step 1a, a living polymerization initiator is used to polymerize a (meth)acrylate monomer having a hydrolyzable silyl group. As the living polymerization initiator, for example, an initiator having one halogen group in the molecule can be used. The amount of the (meth)acrylate monomer having a hydrolyzable silyl group can be 1 to 10 molar equivalents with respect to 1 molar equivalent of the initiator. If necessary, 1 to 100 molar equivalents of a (meth)acrylic acid ester monomer having no hydrolyzable silyl group may be polymerized together. Preferably, the amount of (meth)acrylic acid ester monomer having a hydrolyzable silyl group added to the reaction system in step 1a accounts for more than 3% by weight of the monomer mixture added to the reaction system in step 1a. there is

In step 2a, a (meth)acrylate monomer having no hydrolyzable silyl group is added to the reaction system after step 1a and polymerized. The amount of the (meth)acrylic acid ester monomer having no hydrolyzable silyl group to be added may be 2 to 600 molar equivalents with respect to 1 molar equivalent of the polymer obtained in step 1a. In step 2a, a (meth)acrylate monomer having a hydrolyzable silyl group may be added to the reaction system. The amount of the (meth)acrylic acid ester monomer having a hydrolyzable silyl group added to the reaction system in step 2a accounts for 0 to 3% by weight of the monomer mixture added to the reaction system in step 2a.

In step 1b, a living polymerization initiator is used to polymerize a (meth)acrylic acid ester monomer having no hydrolyzable silyl group. As the living polymerization initiator, the same one as in step 1a can be used. The amount of the (meth)acrylic acid ester monomer having no hydrolyzable silyl group can be 2 to 600 molar equivalents with respect to 1 molar equivalent of the initiator. In step 1b, a (meth)acrylate monomer having a hydrolyzable silyl group may be added to the reaction system. The amount of (meth)acrylic acid ester monomer having a hydrolyzable silyl group added to the reaction system in step 1b accounts for 0 to 3% by weight of the monomer mixture added to the reaction system in step 1b.

In the 2b step, a (meth)acrylate monomer having a hydrolyzable silyl group is added to the reaction system after the 1b step and polymerized. The amount of the (meth)acrylic acid ester monomer having a hydrolyzable silyl group can be 1 to 10 molar equivalents with respect to 1 molar equivalent of the polymer obtained in step 1b. If necessary, 1 to 100 molar equivalents of a (meth)acrylic acid ester monomer having no hydrolyzable silyl group may be polymerized together. Preferably, the amount of the (meth)acrylic acid ester monomer having a hydrolyzable silyl group added to the reaction system in step 2b accounts for more than 3% by weight of the monomer mixture added to the reaction system in step 2b. there is

In the above steps, examples of the "(meth)acrylic acid ester monomer having no hydrolyzable silyl group" include the above-mentioned (meth)acrylic acid ester monomers (α), (β), (γ), ( δ). This also applies to the following description.

(When the polymer has an XYX triblock structure)
The (meth)acrylic polymer (A1), which is a molecule with an XYX triblock structure, can be produced by performing an additional polymerization step (a) after the above steps 1a and 2a. At this time, the X block containing relatively many hydrolyzable silyl groups is formed by the step 1a and the additional polymerization step (a). Regarding this manufacturing method, the description in JP-A-2018-162394 can be referred to.

In the additional polymerization step (a), a (meth)acrylic acid ester monomer having a hydrolyzable silyl group is added to the reaction system after step 2a for polymerization. The amount of the (meth)acrylic acid ester monomer having a hydrolyzable silyl group may be 1 to 10 molar equivalents with respect to 1 molar equivalent of the polymer obtained in step 2a. If necessary, 1 to 100 molar equivalents of a (meth)acrylic acid ester monomer having no hydrolyzable silyl group may be polymerized together. Preferably, the amount of (meth)acrylic acid ester monomer having a hydrolyzable silyl group added to the reaction system in the additional polymerization step (a) is greater than 3% by weight of the monomer mixture added to the reaction system in that step. occupies

(If the polymer has 4 or more blocks)
A (meth)acrylic polymer (A1) having four or more blocks can be produced by appropriately combining the aforementioned Steps 1a, 2a, 1b, 2b and additional polymerization steps. For example, a (meth)acrylic polymer (A1) having an XYXY tetrablock structure can be produced.

When the production method according to the second aspect is employed, halogen atoms may remain at one end or both ends of the molecule of the (meth)acrylic polymer (A1) (extended end of the molecule during polymerization). . In one embodiment, the (meth)acrylic polymer (A1) has an average of 1 or more halogen atoms per extended end of the molecule during polymerization.

(Comparison between the first aspect and the second aspect)
In the production method according to the first aspect, at most two hydrolyzable silyl groups can be introduced into the (meth)acrylic polymer. In contrast, the production method according to the second aspect can introduce two or more hydrolyzable silyl groups into the (meth)acrylic polymer. Moreover, the production method according to the first aspect utilizes a hydrosilane compound having a hydrolyzable silyl group to introduce a hydrolyzable silyl group. In contrast, in the production method according to the second aspect, a hydrolyzable silyl group is introduced using an acrylic acid ester monomer having a hydrolyzable silyl group.

<1-2. Thermal base generator (B)>
In one embodiment, the curable composition in this production method contains a thermal base generator (B). When the curable composition contains the (meth)acrylic polymer (A) and the thermal base generator (B), it is cured by heating.

Examples of the thermal base generator (B) include 1,8-diazabicyclo[5.4.0]undec-7-ene (hereinafter also referred to as DBU) compounds, 1,5-diazabicyclo[4. 3.0]-5-nonene (hereinafter also referred to as DBN) compounds, phenylphosphine derivative salts, ureas, amines, ammonium salts and the like.

The thermal base generator (B) is preferably liquid at room temperature or a mixture of liquid and solid from the viewpoint of handling. Examples of such thermal base generator (B) include 2-ethylhexanoate of DBN, bis(2-morpholinoethyl)ether, 1,1′-[[3-(dimethylamino)propyl]imino]bis (2-propanol), triethylmethylammonium 2-ethylhexane salt, and the like.

The thermal base generator (B) is more preferably a DBU compound from the viewpoint of high reactivity with the (meth)acrylic polymer (A) and improvement in the curing speed of the curable composition. Or a salt of a derivative thereof with an organic acid is more preferable. Incidentally, DBU alone cannot be said to be a thermal base generator.

Examples of the salt of DBU and an organic acid include phenol salt of DBU, 2-ethylhexanoate of DBU, formate of DBU, o-phthalate of DBU, p-toluenesulfonate of DBU, and DBU. Neodecanoate and trimellitate of DBU are included. A commercial product may be used as the thermal base generator (B). For example, in the case of a 2-ethylhexane salt of DBU, trade name: U-CAT SA102 manufactured by San-Apro Co., Ltd. may be used.

Examples of the derivative of DBU include DBU benzyl modification and the like. Examples of the salt of the DBU derivative and organic acid include tetraphenylborate salt of benzyl-modified DBU.

Further specific examples of the thermal base generator (B) include compounds represented by the following formulas.

The content of the thermal base generator (B) in the curable composition is preferably 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight, relative to 100 parts by weight of the (meth)acrylic polymer (A). parts is more preferred, and 0.5 to 2 parts by weight is even more preferred. If the content of the thermal base generator (B) is 10 parts by weight or less, the storage stability is improved, and if it is 0.01 parts by weight or more, the curing speed is improved.

<1-3. Phosphate-containing thermal acid generator (C)>
In another embodiment, the curable composition in this manufacturing method contains a phosphate-containing thermal acid generator (C). When the curable composition contains the (meth)acrylic polymer (A) and the phosphate-containing thermal acid generator (C), it is cured by heating. When a phosphate-free thermal acid generator is used, the curing speed of the curable composition decreases, as shown in the examples described later.

The phosphate-containing thermal acid generator (C) includes sulfonium salt-type thermal acid generators and iodonium salt-type thermal acid generators. Examples of such a phosphate-containing thermal acid generator (C) include TA-100 and IK-1 (trade names, manufactured by San-Apro Co., Ltd.). The phosphate-containing thermal acid generator (C) may also be a sulfonium salt or iodonium salt containing phosphorus oxoacid. Further, as the phosphate-containing thermal acid generator (C) other than the above, for example, trade names NACURE4000, NACURE4054J, NACURE4167 manufactured by Kusumoto Kasei Co., Ltd., and the like can be mentioned.

Further specific examples of the phosphate-containing thermal acid generator (C) include compounds represented by the following formulas.

The content of the phosphate-containing thermal acid generator (C) in the curable composition is preferably 0.01 to 10 parts by weight, preferably 0.01 to 10 parts by weight, based on 100 parts by weight of the (meth)acrylic polymer (A). 1 to 5 parts by weight is more preferred, and 0.5 to 2 parts by weight is even more preferred. If the content of the phosphate-containing thermal acid generator (C) is 10 parts by weight or less, the storage stability is improved, and if it is 0.01 parts by weight or more, the curing speed is improved.

<1-4. Anionic surfactant>
When the curable composition in this production method contains a phosphate-containing thermal acid generator (C), it is preferred that the curable composition further contains an anionic surfactant (D). By adding the anionic surfactant (D) to the curable composition containing the phosphate-containing thermal acid generator (C), the storage stability can be improved.

Examples of anionic surfactants (D) include alkyl sulfates, polyoxyethylene alkyl ether sulfates, polyoxyethylene alkylphenyl ether sulfates, polyoxyethylene alkylallyl phenyl ether sulfates, polyoxyethylene benzyl (or styryl)phenyl (or phenyl) salts of sulfates such as phenyl) ether sulfate, polyoxyethylene, polyoxypropylene block polymer sulfate, paraffin (alkane) sulfonate, α-olefin sulfonate, dialkyl sulfosuccinate, alkyl sulfonate, alkylbenzene sulfonate, mono- or dialkylnaphthalene sulfonate, Salts of sulfonates such as naphthalene sulfonate/formalin condensate, dialkyl sulfosuccinate, alkyldiphenyl ether disulfonate, lignin sulfonate, polyoxyethylene alkyl phenyl ether sulfonate, polyoxyethylene alkyl ether sulfosuccinic acid half ester, fatty acid, N-methyl- Fatty acid sarcosinate, resin acid, salts of fatty acids such as coconut fatty acid, isopropyl phosphate, polyoxyethylene alkyl ether phosphate, polyoxyethylene allylphenyl ether phosphate, polyoxyethylene mono- or dialkylphenyl ether phosphate, polyoxyethylene benzyl (or styryl )-modified phenyl (or phenylphenyl) ether phosphate, polyoxyethylene/polyoxypropylene block polymer, phosphatidylcholine phosphatidylethanolimine (lecithin), and phosphate salts such as alkyl phosphates. Among these, from the viewpoint of improving the storage stability of the curable composition, phosphate ester salts are preferable. The anionic surfactant (D) may be, for example, a polyoxyethylene allylphenyl ether phosphate amine salt manufactured by Takemoto Yushi, under the trade name Nucalgen FS-3PG. Moreover, although the kind of said salt is not specifically limited, For example, sodium salt, potassium salt, etc. may be used.

The content of the anionic surfactant (D) in the curable composition of this production method is preferably 0.1 to 20 parts by weight with respect to 100 parts by weight of the (meth)acrylic polymer (A), and 1 to 15 parts by weight is more preferred, and 5 to 10 parts by weight is even more preferred. If the content of the anionic surfactant (D) is 20 parts by weight or less, the curability of the curable composition is improved, and if it is 0.1 parts by weight or more, the storage stability of the curable composition is improved. . The anionic surfactant (D) may be used alone or in combination of two or more.

<1-5. Silane coupling agent>
The curable composition in this production method may contain a silane coupling agent (E). The silane coupling agent (E) has a function as an adhesion imparting agent. Therefore, by including the silane coupling agent (E) in the curable composition, the adhesiveness of the cured product can be improved.

Specific examples of the silane coupling agent (E) include isocyanate group-containing silanes (γ-isocyanatopropyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-isocyanatopropylmethyldiethoxysilane, γ-isocyanatopropylmethyldimethoxysilane, silane, etc.); amino group-containing silanes (γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, N-(β-aminoethyl )-γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltriethoxysilane, N-(β-amino ethyl)-γ-aminopropylmethyldiethoxysilane, γ-ureidopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N-benzyl-γ-aminopropyltrimethoxysilane, N-vinylbenzyl-γ -aminopropyltriethoxysilane, etc.); mercapto group-containing silanes (γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxysilane, etc.); Epoxy group-containing silanes (γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane , 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, etc.); carboxysilanes (β-carboxyethyltriethoxysilane, β-carboxyethylphenylbis(2-methoxyethoxy)silane, N-(β-carboxy methyl)aminoethyl-γ-aminopropyltrimethoxysilane, etc.); Vinyl-type unsaturated group-containing silanes (vinyltrimethoxysilane, vinyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, γ-methacryloyloxypropylmethyldimethoxysilane silane, γ-acryloyloxypropylmethyltriethoxysilane, etc.); halogen-containing silanes (γ-chloropropyltrimethoxysilane, etc.); isocyanurate silanes (tris(trimethoxysilyl)isocyanurate, etc.). In addition, derivatives obtained by modifying silane coupling agents, such as amino-modified silyl polymers, silylated amino polymers, unsaturated aminosilane complexes, phenylamino long-chain alkylsilanes, aminosilylated silicones, and silylated polyesters, are also used as silane coupling agents. can be used as

<1-6. Other Ingredients>
The curable composition in this production method may contain the following components in addition to the above (A) to (E).

(filler)
Examples of fillers include fillers described in paragraph 0158 of JP-A-2005-232419. Among these fillers, crystalline silica, fused silica, dolomite, carbon black, calcium carbonate, titanium oxide and talc are preferred.

In order to obtain a hardened product with high strength, the group consisting of crystalline silica, fused silica, silicic anhydride, hydrated silicic acid, carbon black, surface-treated fine calcium carbonate, calcined clay, clay and activated zinc white is used as a filler. It is preferable to use one or more selected types. Ultrafine powder silica is particularly preferred, and the specific surface area (BET adsorption method) of the silica is preferably 50 m ² /g or more, more preferably 50 to 400 m ² /g, and even more preferably 100 to 300 m ² /g. Silica whose surface is hydrophobically treated with an organosilicon compound (organosilane, organosilazane, diorganopolysiloxane, etc.) is also preferred.

On the other hand, in order to suppress the strength of the cured product and obtain a cured product with elongation, one or more selected from the group consisting of titanium oxide, calcium carbonate, talc, ferric oxide, zinc oxide and shirasu balloon is used. It is preferable to use

The greater the specific surface area of calcium carbonate, the greater the effect of improving the breaking strength and breaking elongation of the cured product. For the purpose of improving the thixotropy of the curable composition and the breaking strength and breaking elongation of the cured product, colloidal calcium carbonate is preferably used. On the other hand, for the purpose of increasing the amount of the curable composition and reducing the cost, it is preferable to use heavy calcium carbonate.

Calcium carbonate subjected to surface treatment is more preferably used. The use of surface-treated calcium carbonate improves the workability of the curable composition and enhances the storage stability effect. Examples of surface treating agents for calcium carbonate include surface treating agents described in paragraph 0161 of JP-A-2005-232419. The amount of this surface treatment agent is preferably 0.1 to 20% by weight, more preferably 1 to 5% by weight, based on the total weight of calcium carbonate. If the blending amount is 0.1% by weight or more, a sufficient effect of improving workability can be obtained. If the blending amount is 20% by weight or less, the storage stability of the curable composition can be maintained without deteriorating.

Only one type of filler may be used, or two or more types may be used in combination. The amount of the filler compounded is preferably 5 to 1,000 parts by weight, more preferably 20 to 500 parts by weight, and even more preferably 40 to 300 parts by weight, based on 100 parts by weight of the (meth)acrylic polymer (A). If the blending amount is 5 parts by weight or more, the effect of improving the breaking strength, breaking elongation, adhesiveness and weather resistant adhesiveness of the cured product can be sufficiently obtained. If the blending amount is 1000 parts by weight or less, the workability of the curable composition is not deteriorated.

(Micro hollow particles)
The curable composition may contain fine hollow particles in addition to the filler. Examples of fine hollow particles include hollow bodies composed of inorganic or organic materials having a diameter of 1 mm or less, preferably 500 μm or less, more preferably 200 μm or less. In particular, hollow microspheres having a true specific gravity of 1.0 g/cm ³ or less are preferable, and hollow microspheres having a true specific gravity of 0.5 g/cm ³ or less are more preferable. By blending fine hollow particles, it is possible to reduce the weight and cost of the cured product without impairing the flexibility and mechanical strength of the cured product.

Examples of inorganic fine hollow particles include fine hollow particles described in paragraphs 0168 to 0170 of JP-A-2005-232419. In order to improve dispersibility and workability of the curable composition, hollow microparticles whose surface is treated with a surface treatment agent may be used. Examples of surface treatment agents include fatty acids, fatty acid esters, rosin, lignin rosinate, silane coupling agents, titanium coupling agents, aluminum coupling agents, and polypropylene glycol.

Only one type of fine hollow particles may be used, or two or more types may be used in combination. The amount of the hollow microparticles is preferably 0.1 to 50 parts by weight, more preferably 0.1 to 30 parts by weight, per 100 parts by weight of the (meth)acrylic polymer (A). If the blending amount is 0.1 part by weight or more, the effect of weight reduction can be sufficiently obtained. If the blending amount is 50 parts by weight or less, the physical properties of the cured product can be sufficiently maintained. The amount of hollow microparticles having a specific gravity of 0.1 or more is preferably 3 to 50 parts by weight, more preferably 5 to 30 parts by weight.

(Antioxidant)
Examples of antioxidants include p-phenylenediamine antioxidants, amine antioxidants, and hindered phenol antioxidants. Antioxidants also include secondary antioxidants (phosphorus-based antioxidants, sulfur-based antioxidants, etc.). Examples of antioxidants include 4,4′-bis(α,α-dimethylbenzyl)diphenylamine and the like.

Only one type of antioxidant may be used, or two or more types may be used in combination. The content of the antioxidant is preferably 0.1 to 10 parts by weight, more preferably 0.5 to 5 parts by weight, per 100 parts by weight of the (meth)acrylic polymer (A).

(Plasticizer)
Examples of plasticizers include plasticizers described in paragraph 0173 of JP-A-2005-232419. Among these, polyester-based plasticizers and vinyl-based polymers are preferable because they have a remarkable viscosity-reducing effect and have a low volatilization rate during a heat resistance test.

It is also preferable to blend a polymeric plasticizer. Polymeric plasticizers can maintain their initial physical properties over a longer period of time than low-molecular weight plasticizers. The number average molecular weight of the polymeric plasticizer is preferably 500 to 15,000, more preferably 800 to 10,000, even more preferably 1,000 to 8,000. If the number molecular average amount is 500 or more, the outflow of the plasticizer due to heating or contact with liquid can be prevented. If the number average molecular weight is 15,000 or less, the increase in viscosity can be suppressed and workability can be ensured.

The molecular weight distribution of the polymeric plasticizer is preferably less than 1.8, followed by 1.7 or less, 1.6 or less, 1.5 or less, 1.4 or less, and 1.3 or less in this order.

From the viewpoints of compatibility with the (meth)acrylic polymer (A), weather resistance, and heat aging resistance, the polymeric plasticizer is preferably a vinyl polymer. Among vinyl polymers, (meth)acrylic polymers are preferred, and acrylic polymers are more preferred. Acrylic polymers can be produced by solution polymerization or solventless synthesis methods. Acrylic plasticizers produced by a solventless synthesis method are produced by a high-temperature continuous polymerization method without using a solvent or a chain transfer agent (US Pat. No. 4,414,370, JP-A-59- 6207, JP-B-5-58005, JP-A-1-313522, US Pat. No. 5,010,166, etc.). Specific examples of acrylic plasticizers produced by a solventless synthesis method include Toagoseihin UP series.

Other preferred acrylic polymers include polymers obtained by living radical polymerization. An acrylic polymer obtained by living radical polymerization (particularly preferably, atom transfer radical polymerization) is preferable in that it has a narrow molecular weight distribution and a low viscosity.

Only one plasticizer may be used, or two or more plasticizers may be used in combination. In one embodiment, both polymeric plasticizers and small molecular plasticizers may be incorporated. A plasticizer may be blended during the production of the (meth)acrylic polymer (A).

The blending amount of the plasticizer is preferably 1 to 100 parts by weight, more preferably 5 to 50 parts by weight, per 100 parts by weight of the (meth)acrylic polymer (A). If the blending amount is 1 part by weight or more, the effect as a plasticizer is fully exhibited. If the blending amount is 100 parts by weight or less, the mechanical strength of the cured product is not lowered.

(reactive diluent)
The curable composition may contain a reactive diluent in addition to the plasticizer. As the reactive diluent, an organic compound having a boiling point of 100° C. or higher at normal pressure is particularly preferred. Since such an organic compound does not volatilize when the curable composition is cured, it is possible to suppress changes in shape before and after curing and adverse effects on the environment. Specific examples of reactive diluents include 1-octene, 4-vinylcyclohexene, allyl acetate, 1,1-diacetoxy-2-propene, methyl 1-undecenoate, and 8-acetoxy-1,6-octadiene. .

Only one type of reactive diluent may be used, or two or more types may be used in combination. The amount of the reactive diluent compounded is preferably 0.1 to 100 parts by weight, more preferably 0.5 to 70 parts by weight, and still more preferably 100 parts by weight of the (meth)acrylic polymer (A). is 1 to 50 parts by weight.

(light stabilizer)
Examples of light stabilizers include [Kenichi Saruwatari et al., Antioxidant Handbook, Taiseisha, 1976] [Zenjiro Osawa, Deterioration and Stabilization of Polymeric Materials, CMC, 1990, pp.235-242] and the like.

Preferred light stabilizers include UV absorbers. Specific examples of UV absorbers include benzotriazole compounds (tinuvin P, tinuvin 234, tinuvin 320, tinuvin 326, tinuvin 327, tinuvin 329, tinuvin 213, etc.); triazine compounds (tinuvin 1577, etc.); benzophenone compounds ( CHIMASSORB81, etc.) and benzoate compounds (tinuvin 120, etc.). Other preferred light stabilizers include hindered amine compounds. Examples of hindered amine compounds include compounds described in JP-A-2006-274084. A synergistic effect may also be obtained from a mode in which the ultraviolet absorber and the hindered amine compound are combined, and therefore preferred.

A mode in which the light stabilizer and the antioxidant described above are combined is preferable because it exhibits a synergistic effect and may improve weather resistance in particular. Products containing both light stabilizers and antioxidants (tinuvin C353, tinuvin B75, etc.) may be formulated.

The blending amount of the light stabilizer is preferably 0.1 to 10 parts by weight with respect to 100 parts by weight of the (meth)acrylic polymer (A). If the blending amount is 0.1 parts by weight or more, an effect of improving weather resistance can be obtained. Even if the blending amount exceeds 10 parts by weight, there is no great difference in the effect obtained, so 10 parts by weight or less is economically preferable.

(Adhesion imparting agent)
Examples of adhesiveness-imparting agents include vinyl-based monomers having a polar group, and vinyl-based monomers having an acidic group are preferred. More specific examples of substances are described in paragraph 0184 of JP-A-2005-232419.

Examples of vinyl monomers having a polar group include carboxy group-containing monomers and esters thereof, sulfonic acid group-containing monomers, and phosphoric acid group-containing monomers. Specific examples of carboxy group-containing monomers include (meth)acrylic acid, acryloxypropionic acid, citraconic acid, fumaric acid, itaconic acid, crotonic acid, maleic acid, maleic anhydride and derivatives thereof. Specific examples of esters of carboxy group-containing monomers include maleic acid esters, 2-(meth)acryloyloxyethylsuccinic acid, and 2-(meth)acryloyloxyethylhexahydrophthalic acid. Specific examples of sulfonic acid group-containing monomers include vinylsulfonic acid, (meth)acrylsulfonic acid, allylsulfonic acid, styrenesulfonic acid, vinylbenzenesulfonic acid, 2-acrylamido-2-methylpropanesulfones, and these salt of Specific examples of phosphoric acid group-containing monomers include 2-((meth)acryloylciethyl phosphate), 2-(meth)acryloyloxypropyl phosphate, 2-(meth)acryloyloxy-3-chloropropylphosphate, 2 -(meth)acryloyloxyethylphenyl phosphate. Among these, phosphate group-containing monomers are preferred. Moreover, these monomers may have two or more polymerizable groups.

Examples of adhesion imparting agents other than vinyl-based monomers having a polar group include epoxy resins, phenol resins, modified phenol resins, cyclopentadiene-phenol resins, xylene resins, coumarone resins, petroleum resins, terpene resins, and terpene phenols. Resins, rosin ester resin sulfur, alkyl titanates, aromatic polyisocyanates.

Only one type of adhesiveness imparting agent may be used, or two or more types may be used in combination. The amount of the adhesion-imparting agent is preferably 0.01 to 20 parts by weight, more preferably 0.1 to 10 parts by weight, and 0.5 parts by weight with respect to 100 parts by weight of the (meth)acrylic polymer (A). ~5 parts by weight is more preferred. If the blending amount is 0.01 part by weight or more, a sufficient effect of improving adhesion can be obtained. If the blending amount is 20 parts by weight or less, the physical properties of the cured product are less likely to deteriorate.

(solvent)
Examples of solvents include aromatic hydrocarbon solvents (toluene, xylene, etc.); ester solvents (ethyl acetate, butyl acetate, amyl acetate, cellosolve acetate, etc.); ketone solvents (acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketones, etc.). These solvents may be those used during the production of the (meth)acrylic polymer (A).

(Other condensation catalysts)
The curable composition in this production method may contain a condensation catalyst other than the thermal base generator (B) or the phosphate-containing thermal acid generator (C). Condensation catalysts include, for example, metal compounds, amines, and phosphate esters. Among these, amines and phosphate esters are preferred from the viewpoint of storage stability of the curable composition. Further, a tin-based curing catalyst containing an organic tin-based compound may be included as a condensation catalyst, but as described above, it is preferable not to include it from the viewpoint of safety.

((meth)acrylic monomer)
The curable composition according to one aspect of the present invention may contain a (meth)acrylic monomer. The (meth)acrylic monomer may be polyfunctional or monofunctional. A polyfunctional (meth)acrylic monomer has the function of improving the mechanical properties of the cured product. In addition, the polyfunctional (meth)acrylic monomer can suppress the tackiness (stickiness) of the surface of the cured product. On the other hand, monofunctional (meth)acrylic monomers have the function of adjusting the viscosity of the curable composition. Therefore, a curable composition containing a monofunctional (meth)acrylic monomer is easy to handle.

(Other additives)
Examples of other additives include flame retardants, antioxidants, radical inhibitors, metal deactivators, antiozonants, phosphorus peroxide decomposers, lubricants, pigments and blowing agents. Only one type of other additives may be used, or two or more types may be used in combination. Specific examples of such additives are described, for example, in JP-B-4-69659, JP-B-7-108928, JP-A-63-254149, and JP-A-64-22904. there is

[2. Method for manufacturing an article sealed with a cured product]
A method for manufacturing an article sealed with a cured product according to one embodiment of the present invention includes a sealing step of forming a cured product on the article by the manufacturing method. The sealing step includes a coating step of applying the above-described curable composition to an article, and a heating step of heating the article coated with the curable composition in a temperature range of 40 to 180 ° C. for 1 to 60 minutes. may have. Note that the heating step is described in [1. Production method of cured product] can be used as appropriate.

In the sealing step, the cured product may be used as a potting material, an adhesive, a coating material, a dipping material, or a molding material. Among these, from the viewpoint that the cured product is excellent in strength and elongation and also excellent in heat resistance, it is particularly preferable to be used as a potting material.

Examples of the articles include automobile parts, train parts, household appliances, machine parts, building materials, electric parts, electronic parts, battery parts, and the like. Among these, the article may be an electronic component. Examples of electronic components include, but are not limited to, flat panel displays such as liquid crystal displays, organic EL displays, and organic TFT displays, printed circuit boards, components mounted on printed circuit boards, and the like.

The sealing step may be performed after the curable composition is applied onto the article by a known method. Specific examples of the coating method include coating using a spray, immersion, syringe, brush, dispenser, coater, and the like. These methods can be appropriately selected depending on the article to be coated. For example, when applying to the above-described flat panel display or the like, a method using a dispenser is preferable from the viewpoint of preventing dripping during and after application and preventing contamination by foreign matter. Moreover, when conformal coating is applied to a printed circuit board and components mounted on the printed circuit board, spraying or dipping is preferable from the viewpoint of productivity.

[3. Curable composition]
The curable composition according to one embodiment of the present invention is a (meth)acrylic polymer (A) having an average of 1.0 or more hydrolyzable silyl groups per molecule at or near the terminal of the molecule. and a thermal base generator (B) or a phosphate-containing thermal acid generator (C), and are used after being cured by heating at 40 to 180°C. For the curable composition, see [1. Production method of cured product] and [2. Method for producing an article sealed with a cured product] can be used as appropriate.

By curing the curable composition by heating, a cured product having excellent strength, elongation and heat resistance can be obtained. Moreover, since the curable composition does not need to contain an organic tin compound as a catalyst, it is also excellent in safety. Therefore, a cured product obtained by curing the curable composition can be used, for example, as a potting material for electronic parts and the like.

The present invention is not limited to the above-described embodiments, but can be modified in various ways within the scope of the claims, and can be obtained by appropriately combining technical means disclosed in different embodiments. is also included in the technical scope of the present invention.

[4. summary〕
The present invention includes the following aspects.
<1>
A (meth)acrylic polymer (A) having an average of 1.0 or more hydrolyzable silyl groups per molecule at or near the terminal of the molecule, and containing a thermal base generator (B) or a phosphate and a thermal acid generator (C).
<2>
The method for producing a cured product according to <1>, wherein the heating time in the curing step is 1 to 60 minutes.
<3>
The method for producing a cured product according to <1> or <2>, wherein the (meth)acrylic polymer (A) has a molecular weight distribution (Mw/Mn) of 1.8 or less.
<4>
The method for producing a cured product according to any one of <1> to <3>, wherein the hydrolyzable silyl group of the (meth)acrylic polymer (A) is a dimethoxymethylsilyl group.
<5>
Any one of <1> to <4>, wherein the thermal base generator (B) is a salt of 1,8-diazabicyclo[5.4.0]undec-7-ene or a derivative thereof and an organic acid. The method for producing the cured product according to .
<6>
The method for producing a cured product according to any one of <1> to <4>, wherein the curable composition contains a phosphate-containing thermal acid generator (C) and further contains an anionic surfactant (D).
<7>
The method for producing a cured product according to <6>, wherein the anionic surfactant (D) is a phosphate ester salt.
<8>
The method for producing a cured product according to any one of <1> to <7>, wherein the curable composition further contains a silane coupling agent (E).
<9>
A method for producing an article sealed with a cured product, comprising a sealing step of forming a cured product on the article by the method for producing a cured product according to any one of <1> to <8>.
<10>
The method for manufacturing an article according to <9>, wherein the article is an electronic component.
<11>
A (meth)acrylic polymer (A) having an average of 1.0 or more hydrolyzable silyl groups per molecule at or near the terminal of the molecule, and containing a thermal base generator (B) or a phosphate and a thermal acid generator (C).

EXAMPLES The present invention will be described in more detail below with reference to examples, but the present invention is not limited only to the following examples.

[Synthesis Example 1: Synthesis of (meth)acrylic polymer (A)]
(Polymerization process)
100 parts by weight of n-butyl acrylate was prepared and deoxygenated. The interior of a stainless steel reaction vessel equipped with a stirrer was deoxidized, and 0.84 parts by weight of cuprous bromide and 40 parts by weight of n-butyl acrylate were added and heated with stirring. 8.79 parts by weight of acetonitrile and 3.51 parts by weight of diethyl-2,5-dibromoadipate (initiator) were added and mixed. After adjusting the temperature of the mixture to about 80° C., pentamethyldiethylenetriamine was added to initiate the polymerization reaction. The remaining 60 parts by weight of n-butyl acrylate were successively added to proceed with the polymerization reaction. During the polymerization reaction, additional pentamethyldiethylenetriamine was appropriately added to adjust the polymerization rate. The total amount of pentamethyldiethylenetriamine used throughout the polymerization process was 0.15 parts by weight. In the polymerization step, overheating of the inside of the system due to the heat of polymerization was prevented, and the temperature inside the system was adjusted to about 80 to about 90°C. When the polymerization reaction rate reached about 95% or more, the volatile matter was removed under reduced pressure to obtain a (meth)acrylic polymer.

(Diene reaction step)
21 parts by weight of 1,7-octadiene, 35 parts by weight of acetonitrile, and 0.68 parts by weight of pentamethyldiethylenetriamine were added to the (meth)acrylic polymer obtained through the polymerization process. The temperature in the system was adjusted to about 80° C. to about 90° C., and the mixture was heated and stirred for several hours to allow 1,7-octadiene to react with the terminal of the polymer. Acetonitrile and unreacted 1,7-octadiene were removed by devolatilization under reduced pressure to obtain a (meth)acrylic polymer having terminal alkenyl groups.

(Crude purification step)
A (meth)acrylic polymer having an alkenyl group at its terminal obtained through the diene reaction step was diluted with toluene. 1 part by weight of filter aid, 0.5 parts by weight of adsorbent (Kyoward 700SEN, manufactured by Kyowa Chemical Industry Co., Ltd.), and 0.5 parts by weight of hydrotalcite (Kyoward 500SH, manufactured by Kyowa Chemical Industry Co., Ltd.) ) was added, and the mixture was heated and stirred at about 80 to 100° C., and the solid component was separated by filtration. The filtrate was concentrated to obtain a crude product.

(Refining process)
0.2 parts by weight of a heat stabilizer (Sumilizer GS: manufactured by Sumitomo Chemical Co., Ltd.) and adsorbents (Kyoward 700SEN and Kyoward 500SH) were added to the crude product obtained through the crude purification step. The temperature in the system was raised while the obtained mixture was devolatilized under reduced pressure and heated and stirred. At a high temperature of about 170 to about 200° C., the mixture was devolatilized under reduced pressure and heated and stirred for about several hours. Next, adsorbents (Kyoward 700SEN and Kyoward 500SH) and toluene (about 10 times the weight of the polymer) were added, and the mixture was heated and stirred at a high temperature of about 170 to about 200°C for several hours. . The resulting treated liquid was diluted with toluene and the adsorbent was filtered off. The filtrate was concentrated to obtain a purified product (a (meth)acrylic polymer having an alkenyl group at its end).

(Silylation step)
3.2 parts by weight of methyldimethoxysilane, 1.6 parts by weight of methyl orthoformate, 0.0010 parts by weight of a platinum catalyst (bis(1,3-divinyl-1, 1,3,3-tetramethyldisiloxane (isopropanol solution of platinum complex catalyst) was mixed, and heated and stirred at about 100°C. After heating and stirring for about 1 hour, volatile matter such as unreacted methyldimethoxysilane was distilled off under reduced pressure to obtain a (meth)acrylic polymer (A) having a dimethoxymethylsilyl group at the end of the molecule.

The obtained polymer (A) had a number average molecular weight of about 13,800 and a molecular weight distribution of 1.3. The average number of dimethoxymethylsilyl groups introduced into polymer (A) was about 1.8 per molecule (measured by ¹ H NMR analysis).

[Materials used in Examples and Comparative Examples]
Materials other than the (meth)acrylic polymer (A) used in the following examples and comparative examples are as follows.

Thermal base generator (B): U-CAT SA102 (manufactured by San-Apro, salt of DBU and 2-ethylhexane)
Phosphate-containing thermal acid generator (C): NACURE4167 (manufactured by KING INDUSTRIES, phosphoric acid block catalyst)
Anionic surfactant (D): Nucalgen FS-3PG (manufactured by Takemoto Yushi, polyoxyethylene allylphenyl ether phosphate amine salt)
Strong base: DBU (manufactured by Tokyo Kasei)
Phosphate-free thermal acid generator: NACURE2500 (manufactured by KING INDUSTRIES, p-toluic acid blocked acid catalyst)
[Examples 1 to 3]
Each component was mixed so that it might become the composition (weight part) of Table 1. Specifically, the (meth)acrylic polymer (A) and the thermal base generator (B) were added to a disposable cup and stirred with a spatula. Further, stirring (1,600 rpm×1.5 minutes) and defoaming (2,200 rpm×3 minutes) were carried out with Awatori Mixer ARE-310 (manufactured by Thinky) to obtain a curable composition.

[Comparative Example 1]
A curable composition was obtained in the same manner as in Examples 1 to 3, except that the thermal base generator (B) was changed to a strong base.

[Examples 4 and 5]
Each component was mixed so that it might become the composition (weight part) of Table 2. Specifically, the (meth)acrylic polymer (A) and the anionic surfactant (D) were added to a disposable cup and stirred with a spatula. Next, the phosphate-containing thermal acid generator (C) was added and stirred again with a spatula. Further, stirring (1,600 rpm×1.5 minutes) and defoaming (2,200 rpm×3 minutes) were carried out with Awatori Mixer ARE-310 (manufactured by Thinky) to obtain a curable composition.

[Example 6]
A curable composition was obtained in the same manner as in Examples 4 and 5, except that the anionic surfactant (D) was not added.

[Comparative Example 2]
A curable composition was obtained in the same manner as in Examples 4 and 5, except that the phosphate-containing thermal acid generator (C) was changed to a phosphate-free thermal acid generator.

[Method for measuring physical properties of curable composition]
(Curability evaluation)
The resulting curable composition was added to the sample bottle to a depth of 2 mm. Curability was evaluated after heating in an oven according to the temperatures and times listed in Tables 1 or 2. Skinning was evaluated by touching the surface of the heated composition with a spatula. If the composition does not adhere to the spatula and the cured product layer formed on the surface is not torn by removing the spatula, 〇, if the composition does not adhere and the cured product layer on the surface is torn by removing the spatula was rated as Δ, uncured, and x when the composition adhered to a spatula. For deep curing, the curability inside the cured product was confirmed by piercing the cured product with a spatula. If the curing has progressed completely and it is in a rubbery state, it will be ○, if curing has progressed but it will be in a rubbery state that is softer than the completely cured state, it will be △, and if it is not cured, it will be ×. bottom.

(Evaluation of storage stability)
The curable composition was evaluated by measuring the viscosity with an E-type viscometer (manufactured by Toki Sangyo Co., Ltd.) immediately after preparation and three days after preparation. Gelation is described when the viscosity cannot be measured because the reaction of the curable composition has progressed and the composition is cured.

〔result〕
From Table 1, all of Examples 1 to 3 using the thermal base generator (B) had a faster curing rate than Comparative Example 1 using DBU alone, which is a strong base, as a condensation catalyst, and deepened in a short time. had hardened. Furthermore, from Table 2, all of Examples 4 to 6 were hardened to a deep portion by heating in a short time, but Comparative Example 2 using a phosphate-free thermal acid generator was not hardened even by heating. In addition, Examples 4 and 5 did not gel after 3 days of storage.

From the above, by using a (meth)acrylic polymer (A) and a thermal base generator (B) or a phosphate-containing thermal acid generator (C), an organic tin compound can be used. It can be said that it is possible to achieve hardening to the deep part in a short time without any need. Moreover, it can be said that when the phosphate-containing thermal acid generator (C) is used, the storage stability can be improved by adding the anionic surfactant (D).

A cured product produced by the production method according to one aspect of the present invention can be used as a potting material, an adhesive, a coating material, and the like.

Claims (11)

a (meth)acrylic polymer (A) having an average of 1.0 or more hydrolyzable silyl groups per molecule at or near the terminal of the molecule;
a thermal base generator (B) or a phosphate-containing thermal acid generator (C);
A method for producing a cured product, comprising a curing step of heating a curable composition containing in a temperature range of 40 to 180 ° C. The method for producing a cured product according to claim 1, wherein the heating time in the curing step is 1 to 60 minutes. The method for producing a cured product according to claim 1 or 2, wherein the (meth)acrylic polymer (A) has a molecular weight distribution (Mw/Mn) of 1.8 or less. The method for producing a cured product according to any one of claims 1 to 3, wherein the hydrolyzable silyl group of the (meth)acrylic polymer (A) is a dimethoxymethylsilyl group. 5. The thermal base generator (B) according to any one of claims 1 to 4, which is a salt of 1,8-diazabicyclo[5.4.0]undec-7-ene or a derivative thereof and an organic acid. The method for producing the cured product according to . The method for producing a cured product according to any one of claims 1 to 4, wherein the curable composition contains a phosphate-containing thermal acid generator (C) and further contains an anionic surfactant (D). The method for producing a cured product according to claim 6, wherein the anionic surfactant (D) is a phosphate ester salt. The method for producing a cured product according to any one of claims 1 to 7, wherein the curable composition further contains a silane coupling agent (E). A method for producing an article sealed with a cured product, comprising a sealing step of forming a cured product on the article by the method for producing a cured product according to any one of claims 1 to 8. 10. The method of manufacturing an article according to claim 9, wherein the article is an electronic component. a (meth)acrylic polymer (A) having an average of 1.0 or more hydrolyzable silyl groups per molecule at or near the terminal of the molecule;
a thermal base generator (B) or a phosphate-containing thermal acid generator (C);
A curable composition for use by heating at 40 to 180 ° C. and curing.