JP2023142069A - Method for producing macromonomer - Google Patents

Abstract

To provide a production method that can produce a macromonomer containing a carboxy group, while suppressing the inactivation of a cobalt catalyst in a reaction step.SOLUTION: According to a production method, a methacrylate including an acetal group is polymerized in a reaction vessel including water, enabling the production of a macromonomer including a carboxy group generated from the hydrolysis of the acetal group.SELECTED DRAWING: None

Description

The present invention relates to a method for producing macromonomers.

Conventionally, polymers obtained by radical polymerization are used in paints, resists, films, dispersants,
Widely used in fields such as surface conditioners and molding materials. These polymers have different physical and chemical properties required depending on their use. These performances can be adjusted, in part, by combining various ethylenically unsaturated monomers as raw materials. However, in recent years, polymer materials have been required to further improve their performance in various applications, and it has become impossible to meet these demands simply by adjusting the combination of the above-mentioned raw materials.

Therefore, in order to further improve the performance of polymers, we have developed polymers in which polymers with different properties are linked in a linear chain (block copolymers), polymers in which polymers with different or the same properties are linked in branches to a backbone polymer (graft copolymers). copolymers) etc. are being considered. For example, catalytic chain transfer polymerization using a cobalt catalyst
A method of obtaining a block/graft copolymer by polymerizing a macromonomer obtained by fer Polymerization (CCTP (hereinafter referred to as CCTP method)) with other copolymerizable monomers has been studied.

In addition, as a method of changing the properties of block/graft copolymers, polar groups (acidic groups,
There is a method of introducing a basic group). In this method, by containing a polar group in the block/graft copolymer, hydrophilicity is improved and the copolymer can be used as a useful pigment dispersant.

One possible method for introducing polar groups into a block/graft copolymer is to use a macromonomer containing a polar group, but in the CCTP method, the cobalt catalyst is deactivated under acidic or basic conditions. It is difficult to efficiently introduce polar groups.

Patent Document 1 discloses a technique for synthesizing a polar group-containing macromonomer by using a solution polymerization method and adding a cobalt catalyst to supplement the deactivated cobalt catalyst.
However, since this method uses a large amount of solvent and a large amount of cobalt catalyst, there is a problem in production cost.

Patent No. 3096645

Therefore, an object of the present invention is to provide a method for producing a macromonomer containing a carboxy group. Another object of the present invention is to provide a method for producing a macromonomer containing a carboxy group while suppressing deactivation of a cobalt catalyst in a reaction step.

As a result of intensive studies to solve the above problems, the present inventors conducted a polymerization reaction of (meth)acrylate containing an acetal group in a reaction vessel containing water, and the carboxy group generated from hydrolysis of the acetal group was The present inventors have discovered that it is possible to produce macromonomers containing the following compounds, leading to the completion of the present invention.

The present invention has the following aspects.
[1] A method for producing a macromonomer containing a carboxy group, in which a polymerizable component containing (meth)acrylate containing an acetal group and water are charged into a reaction vessel and a polymerization reaction is carried out.
[2] The method for producing a macromonomer according to [1], wherein the macromonomer containing a carboxyl group has a structure represented by the following general formula (MM-1).

(In the formula, R' and Y ¹ to Y ⁿ are each independently a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, a heterocyclic group, or a ¹ -alkyloxy group, ^and at least One is a hydrogen atom, and X ¹ to X ⁿ are each independently a hydrogen atom or a methyl group,
Z is a terminal group, and n is a natural number from 2 to 10,000. )
[3] The macro according to [1] or [2], wherein the monomer containing an acetal group is a (meth)acrylate containing a structure represented by the following formula (1), (2) or (3). Method for producing monomers.

( ^{In the formula ,} Indicates a group, R
³ and R ⁵ each represent an alkyl group, cycloalkyl group, or aryl group having 1 to 20 carbon atoms, and R ⁴ and R ⁶ each represent an alkylene group having 1 to 10 carbon atoms. )
[4] Any one of [1] to [3], wherein the polymerization reaction is aqueous polymerization, and the aqueous polymerization is one type selected from the group consisting of suspension polymerization, miniemulsion polymerization, and emulsion polymerization. A method for producing the macromonomer described.
[5] The method for producing a macromonomer according to any one of [1] to [4], which is polymerized in the presence of a chain transfer agent represented by the following formula (7).

(In the formula, R ₁ to R ₄ are each independently an alkyl group, a cycloalkyl group, and an aryl group; (oxy, alkyl, and aryl groups)
[6] Contains 1% by mass or more of (meth)acrylate containing an acetal group, based on a total of 100% by mass of the polymerizable component containing (meth)acrylate containing an acetal group, [1]
The method for producing a macromonomer according to any one of [5].
[7] The macromonomer according to any one of [1] to [6], which contains 80% by mass or more of methacrylate, based on a total of 100% by mass of the polymerizable components containing (meth)acrylate containing the acetal group. Production method.
[8] The macromonomer has a number average molecular weight of 500 to 100,000, [1] to
The method for producing a macromonomer according to any one of [7].

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method which can efficiently manufacture the macromonomer containing a carboxy group can be provided. Further, according to the present invention, it is possible to provide a production method that can efficiently produce a macromonomer containing a carboxy group while suppressing deactivation of a cobalt catalyst in a reaction step.

This embodiment will be described in detail below. Note that what is described below is one embodiment of the present invention, and the present invention is not limited to the following configuration.
In the present invention, "(meth)acrylic" is a general term for "acrylic" and "methacrylic". "(Meth)acrylate" is a generic term for "acrylate" and "methacrylate." Methacrylates are methacrylic acid and methacrylic acid derivatives. Methacrylic acid derivatives include methacrylates and methacrylic esters. What is acrylate?
Acrylic acid and acrylic acid derivatives. Acrylic acid derivatives include acrylates and acrylic esters. "(Meth)acryloyl group" is a general term for "acryloyl group" and "methacryloyl group", and is a group represented by CH ₂ =C(R)-C(=O)-(R is a hydrogen atom or a methyl group). It is. The monomer component before polymerization is referred to as "~monomer", and is sometimes abbreviated as "monomer". In addition, the structural units that make up a polymer are referred to as "monomeric units."
There is a thing.

<(Meth)acrylate (X) containing an acetal group>
The (meth)acrylate (X) containing an acetal group has hydrolyzability.
"Hydrolyzable" means that a decomposition product derived from (meth)acrylate (X) containing an acetal group is obtained by reaction of (meth)acrylate (X) containing an acetal group with water. do. Whether the (meth)acrylate (X) unit containing an acetal group has been hydrolyzed can be confirmed by identifying the functional group (carboxy group, etc.) produced by hydrolysis.
By polymerizing the (meth)acrylate (X) in a reaction vessel containing water, a polymerization reaction and a hydrolysis reaction are allowed to proceed, and a macromonomer (A) containing a carboxyl group can be synthesized.

The (meth)acrylate (X) containing an acetal group preferably has a structure represented by any one of formulas (1) to (3).

( ^{In the formula ,} Indicates a group, R
³ and R ⁵ each represent an alkyl group, cycloalkyl group, or aryl group having 1 to 20 carbon atoms, R ⁴ represents an alkylene group having 1 to 10 carbon atoms, and R ⁶ represents an alkylene group having 2 to 10 carbon atoms. shows. )

In formula (1), X is -O- (etheric oxygen atom), -S- (sulfide sulfur atom)
It may be either. As X, -O- is preferable.

Examples of the alkyl group having 1 to 10 carbon atoms in R ¹ and R ² include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, pentyl group, hexyl group,
Examples include 2-ethylhexyl group.
The number of carbon atoms in the alkyl group in R ¹ and R ² is preferably 1 to 4, more preferably 1 to 3, and even more preferably 1 or 2.

Preferred combinations of R ¹ and R ² include a combination of a hydrogen atom and a methyl group, a combination of a methyl group and a methyl group, a hydrogen atom and an alkyl group having 2 to 10 carbon atoms (hereinafter also referred to as a "long-chain alkyl group") ), a combination of a methyl group and a long-chain alkyl group,
Examples include combinations of hydrogen atoms and hydrogen atoms, and combinations of long-chain alkyl groups and long-chain alkyl groups. Among these, a combination of a hydrogen atom and a methyl group is preferred from the viewpoint of hydrolyzability.

Examples of the alkyl group having 1 to 20 carbon atoms in R ³ include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, pentyl group, hexyl group, 2-ethylhexyl group, decyl group, dodecyl group, Examples include tetradecyl group.
The cycloalkyl group is preferably a cycloalkyl group having 4 to 8 carbon atoms, such as a cyclohexyl group or a cyclopentyl group.
The aryl group is preferably an aryl group having 6 to 20 carbon atoms, such as phenyl group and naphthyl group.
R ³ is preferably an alkyl group or a cycloalkyl group having 1 to 10 carbon atoms.

The alkyl group, cycloalkyl group, and aryl group in R ³ may each have a substituent. When having a substituent, the number of substituents may be one or two or more. Examples of the substituent include a cycloalkyl group, an aryl group, an alkoxy group, an alkanoyloxy group, an aralkyl group, and an acetoxy group.
Among the substituents, the cycloalkyl group and the aryl group include the same ones as the cycloalkyl group and the aryl group in ^R3 , respectively. Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, and the like. Examples of the alkanoyloxy group include an ethanoyloxy group. Examples of the aralkyl group include a benzyl group.

X in formula (2) is the same as X in formula (1), and preferred embodiments are also the same.
Examples of the alkylene group having 1 to 10 carbon atoms in R ⁴ include a methylene group, an ethylene group, a propylene group, a butylene group, a hexylene group, and the like. The number of carbon atoms in the alkylene group is
2 to 7 are preferred, and 3 to 4 are more preferred.
The alkylene group may have a substituent. When having a substituent, the number of substituents may be one or two or more. Examples of the substituent that the alkylene group may have include the same substituents as those for ^R3 .

X in formula (3) is the same as X in formula (1), and preferred embodiments are also the same.
R ⁵ is the same as R ³ in formula (1), and its preferred embodiments are also the same.
Examples of the alkylene group having 2 to 10 carbon atoms for R ⁶ include ethylene group, propylene group, butylene group, and hexylene group. The alkylene group preferably has 2 to 7 carbon atoms, more preferably 3 to 4 carbon atoms.

As the (meth)acrylate (X) containing an acetal group, structure (1), structure (2),
It is preferable that at least one structure selected from the group consisting of structure (3) is included.

As the (meth)acrylate (X) containing an acetal group, for example, the following formula (M1-1
), (M1-2) or (M1-3).

(In the formula, X and R ¹ to R ⁶ have the same meanings as above, and Q represents CH ₂ =CH-COO-, CH ₂
=C(CH ₃ )-COO-, CHR ^x =CH-COO-, CH ₂ =C(CH ₂ R ^x )-C
OO- or CH ₂ ═CR ^X —CH ₂ COO-, and ^R )

In Q, CH ₂ =CH-COO- is an acryloyloxy group, CH ₂ =C(CH ₃ )
-COO- is a methacryloyloxy group.
CH(CH ₃ )=CH-COO- is a crotonoyloxy group (the ethylenically unsaturated bond is trans type) or an isocrotonoyloxy group (the ethylenically unsaturated bond is cis type).
^CHR It is a fumaroyloxy group (the ethylenically unsaturated bond is trans type).
The alkyl ester group in R ^X is represented by -COOR ^X1 . R ^X1 represents an alkyl group. The alkyl group for R ^X1 is preferably an alkyl group having 1 to 6 carbon atoms, and particularly preferably a methyl group.
Q is CHR ^X =CH-COO-, CH ₂ =C ₍ CH ₂ ^R
When R ^X --CH ₂ COO-, R ^X in Q preferably has the same structure as the group to which Q is bonded, or is an alkyl ester group. For example, in the case of the compound represented by formula (M1-1), R ^X in Q is preferably structure (1) (-CR ¹ R ² -XR ³ ) or an alkyl ester group.
CH ₂ =C(CH ₂ ^{R X )} -COO- or CH _{2 =} CR It is an itaconoyloxy group. ^RX is the same as above.
Q is preferably CH ₂ =CH-COO- or CH(CH ₃ ) =CH-COO-.

Specific examples of the monomer represented by formula (M1-1), (M1-2) or (M1-3) are:
Examples include those shown below.

<Macromonomer (A)>
The macromonomer (A) of the present invention is a polymer having a radically polymerizable group. Moreover, the macromonomer (A) of the present invention has a carboxyl group.
When the macromonomer (A) has a radically polymerizable group, the number of radically polymerizable groups that the macromonomer (A) has is not particularly limited, but it is preferably one.

As the radically polymerizable group, a group having an ethylenically unsaturated bond is preferable. Examples of the group having an ethylenically unsaturated bond include CH ₂ =C(COOR)-CH ₂ -, (meta)
Examples include acryloyl group, 2-(hydroxymethyl)acryloyl group, and vinyl group.
Here, R is a hydrogen atom, an alkyl group that may have a substituent, an alicyclic group that may have a substituent, an aryl group that may have a substituent, or an alkyl group that may have a substituent. a heteroaryl group which may have a substituent, a non-aromatic heterocyclic group which may have a substituent, an aralkyl group which may have a substituent, an alkaryl group which may have a substituent group, an organosilyl group that may have a substituent, a (poly)organosiloxane group that may have a substituent, or a 1-alkyloxy group.

Examples of the alkyl group include branched or straight-chain alkyl groups having 1 to 22 carbon atoms. Specific examples of branched or straight-chain alkyl groups having 1 to 22 carbon atoms include methyl group, ethyl group, n
-propyl group, i-propyl group, n-butyl group, t-butyl group, i-butyl group, pentyl group (amyl group), i-pentyl group, hexyl group, heptyl group, 2-ethylhexyl group, octyl group, i-octyl group, nonyl group, i-nonyl group, decyl group, i-decyl group, undecyl group, dodecyl group (lauryl group), tridecyl group, tetradecyl group, pentadecyl group,
Examples include hexadecyl group, heptadecyl group, octadecyl group (stearyl group), i-octadecyl group, nonadecyl group, icosyl group and docosyl group.

The alicyclic group may be monocyclic or polycyclic, for example, a group having 3 to 20 carbon atoms.
Examples include alicyclic groups. The alicyclic group is preferably a saturated alicyclic group, and specific examples include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, bicyclo[2.2.1]heptyl group, and cyclooctyl group. group, adamantyl group, and the like.

Examples of the aryl group include aryl groups having 6 to 18 carbon atoms. Carbon number 6-1
Specific examples of the aryl group in 8 include phenyl group, naphthyl group, and the like.
Examples of the heteroaryl group include a pyridyl group and a carbazolyl group.
Examples of the non-aromatic heterocyclic group include a pyrrolidinyl group, a pyrrolidone group, and a lactam group.
Examples of the aralkyl group include benzyl group and phenylethyl group.

Examples of the organosilyl group include a group represented by -SiR ²¹ R ²² R ²³ . Note that R ²¹ to R ²³ each independently represent an alkyl group that may have a substituent,
Represents an alicyclic group that may have a substituent or an aryl group that may have a substituent.
The alkyl group that may have a substituent, the alicyclic group that may have a substituent, and the aryl group that may have a substituent in R ²¹ to R ²³ are the above-mentioned R Examples include an alkyl group that may have a substituent, an alicyclic group that may have a substituent, and an aryl group that may have a substituent, as explained in . Note that R ²¹ to R ²³ may be the same group or different groups.

Examples of the (poly)organosiloxane group include a group represented by -SiR ²⁴ R ²⁵ -OR ²⁶ or -(SiR ²⁷ R ²⁸ -O-)m-R ²⁹ . R ²⁴ to R ²⁹ each independently represent an alkyl group that may have a substituent, an alicyclic group that may have a substituent, or an aryl group that may have a substituent. where m represents an integer from 1 to 100.
The alkyl group, alicyclic group and aryl group in R ²⁴ to R ²⁹ are respectively R ²¹ to R
Groups similar to those listed in ²³ can be mentioned.

The substituents that these groups may have are not particularly limited, and include, for example, alkyl groups, aryl groups, -COOR ³⁰ , cyano groups, -OR ³¹ , -NR ³² R ³³ , -CON
At least one selected from the group consisting of R ³⁴ R ³⁵ , a halogen atom, an allyl group, an epoxy group, a siloxy group, and a group exhibiting hydrophilicity or ionicity. Here, R ³⁰ ~
R ³⁵ each represents a hydrogen atom, an alkyl group that may have a substituent, an alicyclic group that may have a substituent, or an aryl group that may have a substituent. Examples of the alkyl group, alicyclic group and aryl group for R ³⁰ to R ³⁵ include the same groups as those listed for R ²¹ to R ²³ , respectively.
Note that R ³⁰ in -COOR ³⁰ is preferably a hydrogen atom or an unsubstituted alkyl group. The unsubstituted alkyl group is preferably an alkyl group having 1 to 12 carbon atoms, such as a methyl group.
R ³¹ in -OR ³¹ is preferably a hydrogen atom or an unsubstituted alkyl group. The unsubstituted alkyl group is preferably an alkyl group having 1 to 12 carbon atoms, such as a methyl group.
R ³² and R 33 in -NR ³² R ³³ are each independently preferably a hydrogen atom ^or an unsubstituted alkyl group. The unsubstituted alkyl group is preferably an alkyl group having 1 to 12 carbon atoms, such as a methyl group.
R ³⁴ and R 35 in -CONR ³⁴ R ³⁵ are each independently preferably a hydrogen atom or an unsubstituted ^alkyl group. The unsubstituted alkyl group preferably has 1 to 1 carbon atoms.
Examples of 2 include alkyl groups, such as methyl groups.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Examples of the poly(alkylene oxide) group include poly(alkylene oxide) groups such as polyethylene oxide group and polypropylene oxide group.
Examples of the 1-alkyloxy group include groups represented by the following formulas (4), (5), or (6).

(In the formula, R ¹ to R ⁶ have the same meanings as above.)

Among the above, R is preferably an alkyl group that may have a substituent or an alicyclic group that may have a substituent, such as an unsubstituted alkyl group or an unsubstituted alicyclic group. , or an alicyclic group having an alkyl group as a substituent, such as a methyl group, an ethyl group, an n-propyl group,
i-propyl group, n-butyl group, t-butyl group, pentyl group, hexyl group, heptyl group,
Octyl group, cyclopropyl group, cyclobutyl group, isobornyl group and adamantyl group are preferred, and methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, t-
More preferred are butyl, cyclopropyl, cyclobutyl, isobornyl and adamantyl groups.

Among the above, the macromonomer (A) is preferably a macromonomer in which a radically polymerizable group is introduced at the end of a polymer having a degree of polymerization of 2 or more, and a macromonomer represented by the following formula (MM-1) is preferable. More preferred.

(In the formula, R' and Y ¹ to Y ⁿ are each independently a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, a heterocyclic group, or ^{a 1} -alkyloxy group. At least One is a hydrogen atom. X ¹ to X ⁿ are each independently a hydrogen atom or a methyl group.
Z is a terminal group. n is a natural number from 2 to 10,000. )

When the (meth)acrylate (X) containing an acetal group is hydrolyzed, a decomposition product containing a carboxyl group is generated. By simultaneously proceeding the polymerization reaction of the macromonomer (A) and the hydrolysis of the (meth)acrylate (X) containing an acetal group, the macromonomer (A) containing a decomposition product containing a carboxyl group as a part of its constituent units is produced. Can be synthesized. In this case, the formula (MM-1)
In the macromonomer represented by, Y ¹ to Y ⁿ at the corresponding positions are hydrogen atoms.

As the alkyl group, cycloalkyl group, aryl group, and heterocyclic group of R' and Y ¹ to Y ⁿ , the same groups as in the macromonomer (A) can be used.

Further, R' and Y ¹ to Y ⁿ may have a substituent. When R' and Y ¹ to Y ⁿ have a substituent, each independently includes an alkyl group, an aryl group, a carboxy group, an alkoxycarbonyl group (-COOR''), a carbamoyl group (-CONR''R''' ), cyano group, hydroxy group, amino group, amide group (-NR''R''), halogen atom, allyl group, epoxy group, alkoxy group (-OR''), and exhibits hydrophilic or ionicity. Examples include groups or atoms selected from the group consisting of groups.

Typical examples of each substituent include a methoxycarbonyl group for the alkoxycarbonyl group, an N-methylcarbamoyl group and an N,N-dimethylcarbamoyl group for the carbamoyl group, and a dimethylamide group for the amide group. Examples of the halogen atom include a fluorine atom, chlorine atom, bromine atom, and iodine atom; examples of the alkoxy group include a methoxy group; and examples of the group exhibiting hydrophilicity or ionicity include an alkali salt of a carboxy group. Alternatively, examples thereof include alkali salts of sulfoxyl groups, poly(alkylene oxide) groups such as polyethylene oxide groups and polypropylene oxide groups, and cationic substituents such as quaternary ammonium bases.

X ¹ to X ⁿ are each a hydrogen atom or a methyl group, preferably a methyl group. moreover,
From the viewpoint of ease of synthesizing the macromonomer (A), it is preferable that half or more of X ¹ to X ⁿ be methyl groups.

Z is a terminal group of the macromonomer (A). Examples of the terminal group of the macromonomer (A) include a group derived from a hydrogen atom and a radical polymerization initiator, similar to the terminal group of a polymer obtained by known radical polymerization.

The number average molecular weight Mn of the macromonomer (A) is preferably 500 or more and 100,000 or less. The lower limit of the number average molecular weight Mn of the macromonomer (A) is more preferably 1,000 or more, and even more preferably 1,500 or more. In addition, the number average molecular weight Mn of the macromonomer (A)
The upper limit value of is more preferably 70,000 or less, and even more preferably 50,000 or less. If the number average molecular weight Mn is within the above range, the macromonomer (A) is added to the macromonomer copolymer.
It is possible to impart compatibility and physical properties based on the origin.

The number average molecular weight Mn of the macromonomer (A) is determined by gel permeation chromatography (GPC).
It means a relative value calculated from a calibration curve using polymethyl methacrylate as a standard substance.

<Polymerizable component (Y)>
The polymerizable component (Y) is a monomer that contains (meth)acrylate (X) containing an acetal group and is copolymerizable with (meth)acrylate (X) containing an acetal group. Examples of the polymerizable component (Y) include compounds having a radically polymerizable group. Polymerizable component (Y
) is preferably a group having an ethylenically unsaturated bond.
Various polymerizable components (Y) other than the (meth)acrylate (X) containing an acetal group can be used, for example,
Methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, i-propyl (meth)acrylate, n-butyl (meth)acrylate, i-
Butyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (
meth)acrylate, n-lauryl(meth)acrylate, n-stearyl(meth)acrylate, cyclohexyl(meth)acrylate, phenyl(meth)acrylate, benzyl(meth)acrylate, isobornyl(meth)acrylate, 2-methoxyethyl(
(Meth)acrylates such as meth)acrylate, 2-ethoxyethyl (meth)acrylate, phenoxyethyl (meth)acrylate; 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate; ) acrylate, hydroxyl group-containing (meth)acrylate such as glycerol (meth)acrylate; (
meth)acrylic acid, 2-(meth)acryloyloxyethylhexahydrophthalic acid, 2-
(meth)acryloyloxypropylhexahydrophthalic acid, 2-(meth)acryloyloxyethyl phthalic acid, 2-(meth)acryloyloxypropylphthalic acid, 2-(meth)acryloyloxyethylmaleic acid, 2-(meth)acryloyl Carboxylic acids such as oxypropyl maleic acid, 2-(meth)acryloyloxyethylsuccinic acid, 2-(meth)acryloyloxylopylsuccinic acid, crotonic acid, fumaric acid, maleic acid, itaconic acid, monomethyl maleate, monomethyl itaconate, etc. Group-containing vinyl monomer; maleic anhydride,
Acid anhydride group-containing vinyl monomers such as itaconic anhydride; glycicyl (meth)acrylate,
Epoxy group-containing vinyl monomers such as glycicyl α-ethyl acrylate and 3,4-epoxybutyl (meth)acrylate; amino group-containing (meth)acrylates such as dimethylaminoethyl (meth)acrylate and diethylaminoethyl (meth)acrylate Vinyl monomers: (meth)acrylamide, N-t-butyl (meth)acrylamide, N-methylol (meth)acrylamide, N-methoxymethyl (meth)acrylamide, N-butoxymethyl (meth)acrylamide, Vinyl monomers containing amide groups such as acetone acrylamide, maleic acid amide, and maleimide; vinyl monomers such as styrene, α-methylstyrene, vinyltoluene, (meth)acrylonitrile, vinyl chloride, vinyl acetate, and vinyl propionate. mer; divinylbenzene, ethylene glycol di(meth)acrylate,
1,3-butylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate ,
Trimethylolpropane tri(meth)acrylate, allyl(meth)acrylate, N,
Examples include polyfunctional vinyl monomers such as N'-methylenebis(meth)acrylamide. One or more of these can be appropriately selected and used.
Among these, methacrylate (methacrylic acid ester) is preferred in terms of monomer availability.
As the methacrylate, methyl methacrylate, n-butyl methacrylate, lauryl methacrylate, dodecyl methacrylate, stearyl methacrylate, 2-ethylhexyl methacrylate, glycidyl methacrylate, 2-hydroxyethyl methacrylate and 4-hydroxybutyl methacrylate are preferred, and methyl methacrylate and n-butyl methacrylate are preferred. and 2-ethylhexyl methacrylate are more preferred. ; These monomers may be used alone or in combination of two or more.
It is preferable that at least a portion of the polymerizable component (Y) is a (meth)acrylic monomer.

<Composition of polymerizable component (Y)>
The ratio of (meth)acrylate (X) containing an acetal group to the total 100 mass of the polymerizable component (Y) is preferably 1% by mass or more and 70% by mass or less, more preferably 2% by mass or more and 60% by mass or less, and 5% by mass or more. More preferably, the content is from % by mass to 50% by mass. Contains an acetal group (
If the proportion of meth)acrylate (X) units is equal to or higher than the above lower limit, it contains an acetal group (
The hydrolyzability of meth)acrylate (X) is improved, and a macromonomer (A) with a high content of carboxy groups can be synthesized.

The ratio of methacrylate to the total mass of the polymerizable component (Y) is preferably 80% by mass or more, more preferably 90% by mass or more, and on the other hand, 100% by mass or less. Within the above range, the macromonomer can be easily synthesized.

[Method for producing macromonomer (A)]
Macromonomer (A) can be produced by a known method. Examples of methods for producing macromonomers include a method using a cobalt chain transfer agent (US Pat. No. 4,680,352), a method using an α-substituted unsaturated compound such as α-bromomethylstyrene as a chain transfer agent ( International Publication No. 88/04304), method for chemically bonding polymerizable groups (Japanese Unexamined Patent Publication No. 1983-1988)
-133007, US Pat. No. 5,147,952) and a method using thermal decomposition (Japanese Patent Application Laid-Open No. 11-240854).
Among these, as a method for producing the macromonomer (A), a method using a cobalt chain transfer agent is preferable since the number of production steps is small and a catalyst with a high chain transfer constant is used.

As a method for producing macromonomer (A) using a cobalt chain transfer agent, for example,
Examples include bulk polymerization, solution polymerization, and aqueous dispersion polymerization methods such as suspension polymerization, emulsion polymerization, and miniemulsion polymerization. Among these, in the synthesis of the macromonomer (A), aqueous dispersion is used because the inclusion of water in the reaction vessel facilitates hydrolysis of the structural units derived from (meth)acrylate (X) containing acetal groups. Polymerization methods are preferred. As another method, a method of synthesizing the macromonomer (A) by adding water to a reaction vessel in a solution polymerization method is also effective.

As the cobalt chain transfer agent used in the present invention, a cobalt chain transfer agent represented by formula (7) can be used, and examples thereof include Japanese Patent No. 3587530 and US Pat. No. 452694.
Specification No. 5, Specification No. 4694054, Specification No. 4886861, Specification No. 5324
Those described in Specification No. 879, International Publication No. 95/17435, Japanese Patent Publication No. 9-510499, Japanese Patent Application Laid-open No. 2012-158696, etc. can be used.

In formula (7), R ₁ to R ₄ are each independently an alkyl group, a cycloalkyl group, and an aryl group; X is each independently an F atom, a Cl atom, a Br atom, an OH group, an alkoxy group , aryloxy group, alkyl group and aryl group.

Specifically, the cobalt chain transfer agent includes bis(boron difluorodimethyldioximinocyclohexane) cobalt(II), bis(boron difluorodimethylglyoxymate) cobalt(II), and bis(boron difluorodiphenyl glyoxymate). Cobalt(II), cobalt(II) complex of vicinaliminohydroxyimino compound, cobalt(II) complex of tetraazatetraalkylcyclotetradecatetraene, N,N'-bis(salicylidene)ethylenediaminocobalt(II) complex , cobalt(II) complexes of dialkyldiazadioxodioxodialkyldodecadienes, cobalt(II) porphyrin complexes, and the like. Among them, bis(borondifluorodiphenylglyoxymate)cobalt(II) (R ₁ to R ₄ : phenyl group,
X: F atom) is preferred. One or more of these can be appropriately selected and used.

The amount of cobalt chain transfer agent used is 20 ppm based on 100 parts of the total amount of polymerizable component (Y).
to 350 ppm is preferred. If the amount of cobalt chain transfer agent used is less than 20 ppm, the molecular weight tends to be insufficiently lowered, and if it exceeds 350 ppm, the resulting macromonomer (A
) are easy to color.

Usable radical polymerization initiators include organic peroxides and azo compounds, and can be appropriately selected depending on the solvent and raw materials used in the polymerization reaction. Specific examples of organic peroxides include 2,4-dichlorobenzoyl peroxide, t-butylperoxypivalate, o-methylbenzoyl peroxide, bis-3,5,5-trimethylhexanoyl peroxide, Octanoyl peroxide, 1,1,3,3-tetramethylbutylperoxy 2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate, cyclohexanone peroxide, benzoyl peroxide, methyl ethyl ketone peroxide, Examples include dicumyl peroxide, lauroyl peroxide, diisopropylbenzene hydroperoxide, t-butyl hydroperoxide, di-t-butyl peroxide, and the like. Specific examples of azo compounds include 2,2'-azobisisobutyronitrile, 2,
Examples include 2'-azobis(2,4-dimethylvaleronitrile) and 2,2'-azobis(2,4-dimethyl-4-methoxyvaleronitrile). Among these, 1,1,3,3-tetramethylbutylperoxy 2-ethylhexanoate, 2,
2'-azobisisobutyronitrile and 2,2'-azobis(2,4-dimethylvaleronitrile) are preferred. These radical polymerization initiators can be used alone or in combination of two or more.

The amount of the radical polymerization initiator used is 0.00 parts by mass based on the total of 100 parts by mass of the polymerizable component (Y).
The amount is preferably 0.005 parts by mass or more, more preferably 0.01 parts by mass or more, and even more preferably 0.05 parts by mass or more. It is preferable that the amount of the radical polymerization initiator used is 0.005 or more because the radical polymerization proceeds rapidly. Further, it is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and even more preferably 1 part by mass or less. It is preferable that the amount of the radical polymerization initiator used is 10 parts or less because the radical polymerization proceeds without runaway.

The macromonomer (A) preferably contains methacrylate as a constitutional unit, and the ratio of the methacrylate unit to the total amount of all the constitutional units constituting the macromonomer (A) is:
Although there is no particular limitation, it is preferably 80% by mass or more, particularly preferably 90% by mass or more, and on the other hand, 100% by mass or less. Within the above range, the cobalt chain transfer agent functions efficiently.

[Macromonomer copolymer]
A macromonomer copolymer can be synthesized by copolymerizing the macromonomer (A) and comonomer (d). The comonomer (d) is a monomer that is copolymerizable with the macromonomer (A). Examples of the comonomer (d) include the same monomers as the polymerizable component (Y).

The comonomer (d) preferably contains acrylate from the viewpoint of copolymerization applicability with the macromonomer (A). Acrylate is based on 100 mol% of comonomer (d),
It is preferably 50 mol% or more, more preferably 60 mol% or more, even more preferably 70 mol% or more, and may be 100 mol%.
Content ratio of comonomer (d) units contained in the macromonomer copolymer (unit: mass%
) is preferably 30% by mass or more and 95% by mass or less based on 100% by mass of the total mass of the macromonomer copolymer. If the lower limit of the content of the comonomer (d) is 30% by mass or more, the macromonomer copolymer can have the characteristics of the comonomer (d). The lower limit of the content of the comonomer (d) is preferably 30% by mass or more, more preferably 35% by mass or more, and even more preferably 40% by mass or more. On the other hand, if the upper limit of the content of the comonomer (d) is 95% by mass or less, the macromonomer copolymer can have both the characteristics of the macromonomer (A). The upper limit of the content of the comonomer (d) is preferably 95% by mass or less, more preferably 90% by mass or less, and particularly preferably 85% by mass or less.

By including the macromonomer (A) of the present invention in the macromonomer copolymer, the characteristics of the macromonomer (A) can be imparted to the macromonomer copolymer. For example, since the macromonomer (A) has a carboxy group, the glass transition temperature (Tg) can be made higher than when the macromonomer does not have a carboxy group.

The radical polymerization initiators that can be used in the synthesis of the macromonomer copolymer include the same radical polymerization initiators that can be used in the synthesis of the macromonomer (A), depending on the solvent and raw materials used in the polymerization reaction. It can be selected as appropriate.

EXAMPLES Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to the following Examples unless it exceeds the gist thereof. In each of the following examples, "parts" indicate "parts by mass" and "%" indicate "% by mass" unless otherwise specified.

[Measurement/evaluation method]
<Molecular weight measurement>
The number average molecular weight and weight average molecular weight were calculated in terms of standard polymethyl methacrylate under the following conditions.
Gel filtration chromatography (GPC) device: HLC-8320 column manufactured by Tosoh Corporation Column (TSK-guardcolumn SuperHH (4.6 x 35 mm, manufactured by Tosoh Corporation) and two TSKgel Super HM-H (6.0 x 150mm,
(manufactured by Tosoh Corporation) are connected in series Sample solution: Tetrahydrofuran (THF) solution of macromonomer (sample concentration 0.02g)
/10mL) 10μL
Flow rate: 0.6 mL/min Eluent: THF (stabilizer: butylated hydroxytoluene (BHT))
Column temperature: 40℃

<1HNMR measurement>
Using a JNM-ECZ400 nuclear magnetic resonance apparatus (manufactured by JEOL Ltd.), using deuterium chloroform (100 mg of measurement sample/1 g of deuterium chloroform) or deuterium dimethyl sulfoxide (100 mg of measurement sample/1 g of deuterium dimethyl sulfoxide) as a solvent, Measured at 23°C.

<Measurement of acid value>
1.0 g of macromonomer, 25 mL of toluene, and 25 mL of ethanol were weighed, and 0.05 g of an ethanol solution containing 1% by volume of phenolphthalein as an indicator was added. This solution was titrated with a 0.1 mol/L KOH ethanol solution while stirring, and the end point was the point at which the solution changed color from colorless to pink, and the acid value was calculated using the following formula.
Acid value (mgKOH/g) = A x 5.611
(In the formula, A indicates the amount (mL) of 0.1 mol/L KOH ethanol solution dropped until the end point)

<Production of (meth)acrylate (X) containing acetal group (IBEMA)>
90.1 parts (0.9 mol) of isobutyl vinyl ether, 0.14 parts of hydroquinone, and 0.28 parts of phenothiazine were stirred at room temperature and mixed until uniform. Air (10ml/m
in), 51.7 parts (0.6 mol) of methacrylic acid was added to the reaction solution at a temperature of 6 mol.
The mixture was added dropwise while maintaining the temperature below 0°C. After the dropwise addition, the temperature of the reaction solution was raised to 80° C., and the reaction was allowed to proceed for 6 hours. 158.7 parts (1.8 mol) of t-butyl methyl ether was added to the reaction solution and mixed, and the organic phase was washed once with 200 parts of a 20% by mass aqueous potassium carbonate solution. 4- in the organic phase
0.03 part of benzoyloxy-2,2,6,6-tetramethylpiperidine-N-oxyl was added, and low-boiling components were distilled off using an evaporator. The resulting residue was distilled under reduced pressure to a boiling point of 6.
97.5 parts of 1-isobutoxyethyl methacrylate (IBEMA) at 0°C/3 torr (
0.52 mol) was obtained.

[Dispersant]
<Production of dispersant 1>
In a polymerization apparatus equipped with a stirrer, a cooling tube, a thermometer and a nitrogen gas inlet tube, 900 g of deionized water was added.
1 part, 60 parts of 2-sulfoethyl sodium methacrylate, 10 parts of potassium methacrylate, and 12 parts of methyl methacrylate (MMA) were added thereto and stirred, and the temperature was raised to 50° C. while purging the inside of the polymerization apparatus with nitrogen. Thereto was added 0.08 part of 2,2'-azobis(2-methylpropionamidine) dihydrochloride as a polymerization initiator, and the temperature was further raised to 60°C. After raising the temperature, MMA was continuously added dropwise for 75 minutes at a rate of 0.24 parts/min using a dropping pump. The reaction solution was maintained at 60° C. for 6 hours and then cooled to room temperature to obtain Dispersant 1 having a solid content of 10% by mass as a transparent aqueous solution.

<Production of chain transfer agent 1>
Cobalt(II) acetate tetrahydrate 1.
00 g, 1.93 g of diphenylglyoxime, and 80 mL of diethyl ether which had been previously deoxidized by nitrogen bubbling were added, and the mixture was stirred at room temperature for 30 minutes. Then, 10 mL of boron trifluoride diethyl ether complex was added, and the mixture was further stirred for 6 hours. The mixture was filtered, the solid was washed with diethyl ether, and vacuum dried for 15 hours to obtain 2.12 g of chain transfer agent 1 as a reddish brown solid.

<Example 1>
In a polymerization apparatus equipped with a stirrer, a cooling tube, a thermometer and a nitrogen gas inlet tube, 145 liters of deionized water was added.
1 part, 0.1 part of sodium sulfate, and 0.25 part of dispersant 1 (solid content: 10% by mass) were added and stirred to obtain a uniform aqueous solution. Next, 35 parts of MMA, 55 parts of BMA, 10 parts of IBEMA, MA
0.004 parts of 5 parts chain transfer agent 1 and 0.5 parts of Perocta O (registered trademark) as a polymerization initiator
of the mixture was added to form an aqueous suspension.
Next, the interior of the polymerization apparatus was purged with nitrogen, the temperature was raised to 75°C, and reaction was carried out for 3.5 hours, and in order to further increase the polymerization rate, the temperature was raised to 90°C and held for 1 hour. Thereafter, the reaction solution was cooled to 40° C. to obtain an aqueous suspension containing the macromonomer. The aqueous suspension was filtered, and the residue left on the filter was washed with deionized water, dehydrated, and dried at 40° C. for 16 hours to obtain the macromonomer. Table 1 shows the number average molecular weight and weight average molecular weight of this macromonomer.

<Example 2, 3>
Examples 2 and 3 were carried out in the same manner as in Example 1, except that the amounts of monomers, chain transfer agents, and polymerization initiators were as shown in Table 1, and macromonomers were obtained, respectively. . Table 1 shows the number average molecular weight and weight average molecular weight. In addition, all the units of the blending amounts in Table 1 are parts by mass.

<Comparative example 1>
A polymer was obtained in the same manner as in Example 1, except that the amounts of the monomer, chain transfer agent, and polymerization initiator were as shown in Table 1. In addition, all the units of the blending amounts in Table 1 are parts by mass.

The abbreviations in Table 1 are as follows.
MMA: Methyl methacrylate BMA: Butyl methacrylate IBEMA: 1-isobutoxyethyl methacrylate TBMA: t-butyl methacrylate MA: Methyl acrylate PeroctaO: 1,1,3,3-tetramethylbutyl peroxy 2-ethylhexanoate

The acid value of the macromonomers produced in Examples 1 to 3 was titrated, and the acid value showed a value almost equivalent to the theoretical value when the entire amount of IBEMA-derived structural units was hydrolyzed. In other words, a macromonomer containing a carboxy group was synthesized.

The acid value of the macromonomer produced in Comparative Example 1 was titrated and the value was 0. That is, the structural unit derived from TBMA was not hydrolyzed, and a macromonomer containing no carboxy group was synthesized.

When the polymer produced in Example 1 was subjected to ¹ H NMR measurement, a hydrogen peak at the terminal double bond could be confirmed, indicating that a macromonomer was synthesized. On the other hand, when ¹ H NMR measurement was performed on the polymer produced in Comparative Example 2, no hydrogen peak at the terminal double bond could be confirmed, and no macromonomer was synthesized.

Claims (8)

A method for producing a macromonomer containing a carboxy group, which comprises charging a polymerizable component containing (meth)acrylate containing an acetal group and water into a reaction vessel and carrying out a polymerization reaction. The method for producing a macromonomer according to claim 1, wherein the macromonomer containing a carboxyl group has a structure represented by the following general formula (MM-1).

(In the formula, R' and Y ¹ to Y ⁿ are each independently a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, a heterocyclic group, or a ¹ -alkyloxy group, ^and at least One is a hydrogen atom, and X ¹ to X ⁿ are each independently a hydrogen atom or a methyl group,
Z is a terminal group, and n is a natural number from 2 to 10,000. ) The method for producing a macromonomer according to claim 1 or 2, wherein the monomer containing an acetal group is a (meth)acrylate containing a structure represented by the following formula (1), (2), or (3).

The polymerization reaction is aqueous polymerization, and the aqueous polymerization includes suspension polymerization, miniemulsion polymerization,
The method for producing a macromonomer according to any one of claims 1 to 3, which is one selected from the group consisting of emulsion polymerization. The method for producing a macromonomer according to any one of claims 1 to 4, wherein the macromonomer is polymerized in the presence of a chain transfer agent represented by the following formula (7).

(In the formula, R ₁ to R ₄ are each independently an alkyl group, a cycloalkyl group, and an aryl group; (oxy, alkyl, and aryl groups) Claims 1 to 5, wherein the (meth)acrylate containing an acetal group is contained in an amount of 1% by mass or more based on a total of 100% by mass of the polymerizable component containing the (meth)acrylate containing an acetal group.
The method for producing a macromonomer according to any one of the above. The method for producing a macromonomer according to any one of claims 1 to 5, comprising 80% by mass or more of methacrylate based on a total of 100% by mass of the polymerizable components containing (meth)acrylate containing the acetal group. Claim 1, wherein the macromonomer (A) has a number average molecular weight of 500 to 100,000.
8. The method for producing a macromonomer according to any one of 7.