WO2019240262A1

WO2019240262A1 - Silicone-containing block copolymer

Info

Publication number: WO2019240262A1
Application number: PCT/JP2019/023662
Authority: WO
Inventors: 陽彦沖山
Original assignee: 関西ペイント株式会社
Priority date: 2018-06-15
Filing date: 2019-06-14
Publication date: 2019-12-19
Also published as: JP2021165320A

Abstract

The present invention pertains to a silicone-containing block copolymer having a weight-average molecular weight of 1000-100,000, the silicone-containing block copolymer being obtained by bonding a polymer (A) and a polyfunctional organopolysiloxane to each other, and the polymer (A) being obtained by radical-polymerizing at least one compound selected from the group consisting of methacrylic acid esters, acrylic acid esters, aromatic alkenyls, methacrylamides, and acrylamides in the presence of a compound represented by Z-R-SH [in the formula, R and Z each have the same definitions as set forth in the description].

Description

Silicone-containing block copolymer

The present invention relates to a silicone-containing block copolymer that can be industrialized and synthesized by a simple method.

Silicone additives are useful additives such as paint surface conditioners and antifoaming agents, and are widely used in the paint field. In particular, acrylic-modified silicone compounds are relatively inexpensive among silicone compounds, and have been developed extensively.

Regarding the acrylic modified silicone compound, for example, Patent Document 1 discloses a polymer obtained by radical polymerization of a monomer capable of radical polymerization in the presence of a compound having a thiocarbonylthio group, and a silicone-based polymer. Silicone-containing block copolymers obtained by bonding to each other are disclosed.

Patent Document 2 discloses a process in which 2,4-diphenyl-4-methyl-1-pentene is used to bond a polymer having a double bond at a terminal and a silicone compound having a hydrosilyl group by a hydrosilylation reaction. A method for producing a silicone composite polymer comprising

Japanese Patent No. 4242283 Japanese Laid-Open Patent Publication No. 8-302022

However, since the silicone-containing block copolymer described in Patent Document 1 has a step of converting a thiocarbonylthio group into a mercapto group using a treating agent, there are difficulties in terms of production cost and productivity.

Further, the production method described in Patent Document 2 has a problem in terms of production cost because it requires a large amount of expensive catalyst because of low hydrosilylation reactivity.

The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a silicone-containing block copolymer that can be synthesized by a simple method at a low production cost.

As a result of intensive investigations to achieve the above object, the present inventors obtained a specific radical polymerizable monomer (a) by radical polymerization in the presence of a compound having a specific mercapto group. It has been found that a silicone-containing block copolymer obtained by bonding a polymer (A) and a specific silicone polymer (B) to each other can achieve the above object.

That is, the present invention includes the following aspects.

[1] A polymer (A) obtained by radical polymerization of a radically polymerizable monomer (a) in the presence of a compound having a mercapto group and a silicone polymer (B) are bonded to each other. A silicone-containing block copolymer obtained,
The monomer (a) is at least one compound selected from the group consisting of methacrylic acid esters, acrylic acid esters, aromatic alkenyls, methacrylic acid amides, and acrylic acid amide compounds;
The compound having the mercapto group has the structural formula Z—R—SH [wherein R is a divalent organic group selected from the group consisting of an alkylene group, an arylene group and an aralkylene group (the hydrogen atom of the organic group is a heteroatom) And Z is a reactive functional group selected from the group consisting of hydroxyl, carboxyl and amino groups. And a compound represented by
The silicone polymer (B) is a polyfunctional organopolysiloxane.
A silicone-containing block copolymer having a weight average molecular weight of 1,000 to 100,000.
[2] The silicone-containing block copolymer according to [1], wherein the polymer (A) is a polymer having a carboxyl group, and the silicone polymer (B) is a polymer having an epoxy group.
[3] The silicone polymer (B) is a compound obtained by adding an unsaturated compound containing an epoxy group to a silicone compound containing hydrosilyl groups at both ends [1] or [2 ] The silicone-containing block copolymer described in the above.
[4] Any of [1] to [3], wherein the alkylene group has 1 to 20 carbon atoms, the arylene group has 5 to 14 carbon atoms, and the aralkylene group has 7 to 11 carbon atoms. The silicone-containing block copolymer according to any one of the above.

Since the silicone-containing block copolymer of the present invention has the above-mentioned characteristics, it can be synthesized by a simple method at a low production cost.

Hereinafter, the silicone-containing block copolymer of the present invention will be described in more detail.

The silicone-containing block copolymer of the present invention comprises a polymer (A) obtained by radical polymerization of a radically polymerizable monomer (a) in the presence of a compound having a mercapto group, and a silicone polymer ( B) and a silicone-containing block copolymer obtained by bonding each other,
The monomer (a) is at least one compound selected from the group consisting of methacrylic acid esters, acrylic acid esters, aromatic alkenyls, methacrylic acid amides, and acrylic acid amide compounds;
The compound having the mercapto group has the structural formula Z—R—SH [wherein R is a divalent organic group selected from the group consisting of an alkylene group, an arylene group and an aralkylene group (the hydrogen atom of the organic group is a heteroatom) And Z is a reactive functional group selected from the group consisting of hydroxyl, carboxyl and amino groups. And a compound represented by
The silicone polymer (B) is a polyfunctional organopolysiloxane,
The weight average molecular weight is 1,000 to 100,000.

[Polymer (A)]
The polymer (A) can be obtained by radical polymerization of the radically polymerizable monomer (a) in the presence of a compound having a mercapto group.

The monomer (a) is at least one compound selected from the group consisting of methacrylic acid esters, acrylic acid esters, aromatic alkenyls, methacrylic acid amides, and acrylic acid amide compounds. The above monomers can be used alone or in combination.

Examples of the methacrylic acid ester include methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, tridecyl methacrylate, stearyl methacrylate, Cyclohexyl methacrylate, benzyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, glycidyl methacrylate, tetrahydrofurfuryl methacrylate, ethylene glycol dimethacrylate, di Triethylene glycol methacrylate, tetraethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, trimetac Trimethylol propane, isopropyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, nonyl methacrylate, decyl methacrylate, phenyl methacrylate, toluyl methacrylate, isobornyl methacrylate, 2-methacrylic acid 2- Methoxyethyl, 3-methoxybutyl methacrylate, 2-aminoethyl methacrylate, 2-methacryloyloxypropyltrimethoxysilane, 2-methacryloyloxypropyldimethoxymethylsilane, trifluoromethyl methacrylate, pentafluoroethyl methacrylate, methacrylic acid 2 2,2-trifluoroethyl, triisopropylsilyl methacrylate, and the like.

Examples of the acrylate ester include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, octyl acrylate, Decyl acrylate, phenyl acrylate, toluyl acrylate, benzyl acrylate, isobornyl acrylate, 2-methoxyethyl acrylate, 3-methoxybutyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, acrylic acid Stearyl, glycidyl acrylate, 2-acryloyloxypropyldimethoxymethylsilane, 2-acryloyloxypropyltrimethoxysilane, trifluoromethyl acrylate, pentaful acrylate Roethyl, 2,2,2-trifluoroethyl acrylate, 3-dimethylaminoethyl acrylate, isobutyl acrylate, 4-hydroxybutyl acrylate, t-butyl acrylate, lauryl acrylate, alkyl-modified dipentaerythritol acrylate , Ethylene oxide modified bisphenol A diacrylate, carbitol acrylate, ε-caprolactone modified dipentaerythritol acrylate, caprolactone modified tetrahydrofurfuryl acrylate, caprolactone modified hydroxypivalic acid neopentyl glycol ester diacrylate, ditrimethylolpropane tetraacrylate, di Pentaerythritol hexaacrylate, dipentaerythritol pentaacrylate, tetraethylene glycol acrylate Coal, tetrahydrofurfuryl acrylate, tripropylene glycol acrylate, trimethylolpropane ethoxytriacrylate, trimethylolpropane triacrylate, neopentyl glycol diacrylate, neopentyl glycol hydroxypivalate ester diacrylate, 1,9-nonane acrylic acid Diol, 1,4-butanediol acrylate, 2-propenoic acid [2- [1,1-dimethyl-2-[(1-oxo-2-propenyl) oxy] ethyl] -5-ethyl-1, 3-dioxane-5-yl] methyl ester, 1,6-hexanediol acrylic acid, pentaerythritol triacrylate, 2-acryloyloxypropyl hydrogen phthalate, methyl 3-methoxyacrylate, Le allyl, acrylic acid triisopropylsilyl and the like.

Examples of the aromatic alkenyl include styrene, α-methylstyrene, p-methylstyrene, p-methoxystyrene, divinylbenzene, vinylnaphthalene and the like.

Of these radically polymerizable monomers (a), methyl methacrylate, n-butyl acrylate, and 2-methoxyethyl acrylate can be preferably used from the viewpoint of polymerizability.

The compound having a mercapto group has a structural formula Z—R—SH [wherein R is a divalent organic group selected from the group consisting of an alkylene group, an arylene group and an aralkylene group (the hydrogen atom of the organic group is a heteroatom) And Z is a reactive functional group selected from the group consisting of hydroxyl, carboxyl and amino groups. It is a compound represented by this.

In the silicone-containing block copolymer of the present invention, the compound having a mercapto group acts as a chain transfer agent.

In the structural formula, Z is selected from the group consisting of a hydroxyl group, a carboxyl group, and an amino group, and acts as a reactive functional group in the bond with the silicone polymer (B) described later.

In the structural formula, R is a divalent organic group selected from the group consisting of an alkylene group, an arylene group, and an aralkylene group.

An alkylene group is a divalent saturated hydrocarbon substituent in which two hydrogen atoms are removed from a hydrocarbon. At least one hydrogen atom in the alkylene group may be substituted with a hetero atom. The alkylene group preferably has 1 to 20 carbon atoms, more preferably 1 to 8 carbon atoms, and still more preferably 1 to 3 carbon atoms.

Specific examples of alkylene groups include methylene, ethylene, propylene, isopropylene, n-butylene, t-butylene, sec-butylene, iso-butylene, 2-ethylhexylene, iso- Examples include an octylene group, a dodecylene group, a hexadecylene group, and a behenene group. From the viewpoint of polymerizability, the alkylene group is preferably an ethylene group or an isopropylene group.

The arylene group is a divalent saturated aromatic hydrocarbon substituent obtained by removing two hydrogen atoms from an aromatic hydrocarbon. At least one hydrogen atom in the arylene group may be substituted with a hetero atom. The arylene group preferably has 5 to 14 carbon atoms, and more preferably 6 to 10 carbon atoms.

Specific examples of the arylene group include a benzylene group, a furylene group, a piperidylene group, and a naphthylene group. From the viewpoint of polymerizability, the arylene group is preferably a benzylene group.

The aralkylene group is a divalent organic group obtained by removing one hydrogen atom from the aromatic ring of the aralkyl group. An aralkyl group is an alkyl group (a monovalent saturated hydrocarbon substituent obtained by removing one hydrogen atom from a hydrocarbon) and an aryl group (one hydrogen atom is removed from an aromatic hydrocarbon). A monovalent organic group substituted with a monovalent saturated aromatic hydrocarbon substituent.
At least one hydrogen atom in the aralkylene group may be substituted with a hetero atom. The aralkylene group preferably has 7 to 11 carbon atoms.

Specific examples of the aralkylene group include a xylylene group and a toluenylene group.

In addition, as a hetero atom, a nitrogen atom, an oxygen atom, a sulfur atom, a phosphorus atom, a chlorine atom, an iodine atom, a bromine atom, etc. can be mentioned, for example.

Specific examples of the compound having a mercapto group represented by the structural formula Z—R—SH include 2-mercaptoethanol, 3-mercapto-1-propanol and the like as compounds having a hydroxyl group. .

Examples of the compound having a carboxyl group include thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, 3-mercaptoisobutyric acid, 2-mercaptobenzoic acid and the like.

Examples of the compound having an amino group include 1-aminothiophenol, 4-aminothiophenol, 2-mercaptoethylamine and the like.

Among the above, from the viewpoint of polymerizability, a compound having a carboxyl group can be preferably used.
Among the compounds having a carboxyl group, 2-mercaptopropionic acid and 3-mercaptopropionic acid can be particularly preferably used from the viewpoint of versatility.

The polymer (A) constituting the silicone-containing block copolymer of the present invention can be obtained by radical polymerization of the monomer (a) in the presence of the compound having the mercapto group. At this time, the compound having a mercapto group acts as a chain transfer agent.

The method of radical polymerization in the preparation of the polymer (A) is not particularly limited, and examples thereof include conventionally known methods such as bulk polymerization, solution polymerization, emulsion polymerization, suspension polymerization, and fine suspension polymerization. . Monomers to be subjected to polymerization may be charged into a reactor all at once and reacted, or may be added sequentially.

In the present invention, when the polymer (A) is produced by solution polymerization, the solvent used is not particularly limited, and is a hydrocarbon solvent such as heptane, hexane, octane, mineral spirit, ethyl acetate, n-butyl acetate. Ester solvents such as isobutyl acetate, ethylene glycol monomethyl ether acetate, diethylene glycol monobutyl ether acetate, ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, cyclohexanone, methanol, ethanol, isopropanol, n-butanol, sec- Alcohol solvents such as butanol and isobutanol, tetrahydrofuran, diethyl ether, dibutyl ether, dioxane, ethylene glycol dimethyl ether, ethylene glycol Ether solvents such as rudiethyl ether, amide solvents such as dimethylformamide, diethylformamide, dimethylacetamide, diethylacetamide, toluene, xylene, benzene, Swazol 310 (manufactured by Cosmo Oil), Swazol 1000 (manufactured by Cosmo Oil), An aromatic petroleum solvent such as SWAZOL 1500 (manufactured by Cosmo Oil Co., Ltd.) can be used. These may be used alone or in combination.

In determining the solvent type and solvent amount to be used, the monomer solubility, the solubility of the resulting polymer, the polymerization initiator concentration and monomer concentration appropriate for achieving a sufficient reaction rate, and a mercapto group There is no particular limitation as long as it is determined in consideration of the solubility of the compound, the influence on the human body and the environment, availability, price, and the like.

Of the above solvents, methyl isobutyl ketone and toluene can be preferably used from the viewpoint of polymerizability.

In the present invention, when the polymer (A) is produced by emulsion polymerization or fine suspension polymerization, the emulsifier to be used is not particularly limited, but fatty acid soap such as sodium dodecyl sulfate, rosin acid soap, sodium naphthalenesulfonate formalin. Anionic interfaces such as condensates, sodium alkylbenzene sulfonate, ammonium alkyl sulfate, triethanolamine alkyl sulfate, sodium dialkyl sulfosuccinate, sodium alkyl diphenyl ether disulfonate, sodium polyoxyethylene alkyl ether sulfate, sodium polyoxyethylene alkyl phenyl ether sulfate Activator, polyoxyethylene alkyl ether, polyoxyethylene higher alcohol ether, sorbitan fatty acid ester, polyoxyethylene sorbi Fatty acid esters, polyoxyethylene sorbitol fatty acid esters, glycerin fatty acid esters, polyoxyethylene fatty acid esters, polyoxyethylene alkylamines, alkylalkanolamides and other nonionic surfactants, alkyltrimethylammonium chlorides, alkylamine hydrochlorides, etc. And cationic surfactants. These emulsifiers may be used alone or in combination. If necessary, a dispersant for suspension polymerization described later may be used.

The amount of emulsifier used may be appropriately selected according to the type of emulsifier and the like, and is preferably 0.1 to 30% by mass with respect to the total amount of monomers.

In the present invention, when the polymer (A) is produced by suspension polymerization, the dispersing agent to be used is not particularly limited, and a dispersing agent usually used in this field can be used. Specific examples include partially saponified polyvinyl acetate, polyvinyl alcohol, methyl cellulose, carboxymethyl cellulose, gelatin, polyalkylene oxide, and a dispersant combining an anionic surfactant and a dispersion aid. These may be used alone or in combination. You may use the emulsifier used in the case of the said emulsion polymerization as needed.

The amount of the dispersant used is not particularly limited, but it is usually preferably 0.1 to 30% by mass with respect to the total amount of monomers.

When performing radical polymerization of the monomer (a) in the presence of a compound having a mercapto group, the polymerization initiator to be used is not particularly limited, and a polymerization initiator usually used in this field can be used. Examples of the polymerization initiator include methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide, cyclohexanone peroxide, methylcyclohexanone peroxide, isobutyryl peroxide, 3,5,5-trimethylhexanoyl peroxide, lauroyl peroxide, benzoyl peroxide. Oxide, t-butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, p-menthane hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, di-t-butyl peroxide, t-butyl-α-cumyl peroxide, di-α-cumyl peroxide, 1,4-bis [(t-butylperoxy) isopropyl] benzene, 1,3-bis [ (T-butylperoxy) isopropyl] benzene, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane, 2,5-dimethyl-2,5-bis (t-butylperoxy)- 3-hexyne, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-bis (t-butylperoxy) valerate, 2,2-bis ( t-butylperoxy) butane, t-butylperoxyacetate, t-butylperoxyisobutyrate, t-butylperoxyoctoate, t-butylperoxypivalate, t-butylperoxyneodecanoate, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxybenzoate, t-butylperoxylaurate, 2,5 Dimethyl-2,5-bis (benzoylperoxy) hexane, bis (2-ethylhexyl) peroxydicarbonate, diisopropylperoxydicarbonate, di-sec-butylperoxydicarbonate, di-n-propylperoxydicarbonate Bis (3-methoxybutyl) peroxydicarbonate, bis (2-ethoxyethyl) peroxydicarbonate, bis (4-tert-butylcyclohexyl) peroxydicarbonate, Ot-butyl-O-isopropylperoxy Peroxide-based polymerization initiators such as carbonate and succinic peroxide; 2,2′-azobis- (2-amidinopropane) dihydrochloride, dimethyl 2,2′-azobisisobutyrate, 2,2′-azobis- ( 4-methoxy-2,4-dimethylvaleronitrile), , 2'-azobis (isobutyronitrile), 1,1'-azobis (cyclohexane-1-carbonitrile), azocumene, 2,2'-azobis (2-methylbutyronitrile), 2,2'-azobis -(2,4-dimethylvaleronitrile), 4,4'-azobis (4-cyanovaleric acid), 2- (t-butylazo) -2-cyanopropane, 2,2'-azobis (2,4,4) -Trimethylpentane), 2,2′-azobis (2-methylpropane), VPS-1001 (manufactured by Wako Pure Chemical Industries, Ltd.), VPS-0501 (manufactured by Wako Pure Chemical Industries, Ltd.), etc. Azo polymerization initiators such as molecular azo polymerization initiators; inorganic peroxides such as potassium persulfate and sodium persulfate; vinyl monomers that thermally generate radical species such as styrene; benzoin derivatives Compounds that generate radical species by light such as conductor, benzophenone, acylphosphine oxide, photoredox system; sodium sulfite, sodium thiosulfate, sodium formaldehyde sulfoxylate, ascorbic acid, ferrous sulfate, etc. as a reducing agent, Examples thereof include a redox type polymerization initiator using potassium peroxodisulfate, hydrogen peroxide, t-butyl hydroperoxide and the like as an oxidizing agent. These polymerization initiators can be used alone or in combination.

The amount of the polymerization initiator used is not particularly limited, but the amount of radical species generated during the polymerization is 1 mol or less with respect to 1 mol of the mercapto group in that a polymer having a small molecular weight distribution can be obtained. It is preferable to use a sufficient amount of the polymerization initiator, more preferably to use a polymerization initiator in such an amount that it is 0.5 mol or less, and to use a polymerization initiator in an amount that is 0.3 mol or less. Is particularly preferred.

A temperature at which the half-life is 0.1 to 10 hours, particularly 0.1 to 5 hours, more particularly 0.1 to 1 hour, using a polymerization initiator that is thermally dissociated in that it is easy to control the polymerization. It is preferable to polymerize with.

When polymer (A) is copolymerized using a plurality of monomers (a), the resulting copolymer is a random copolymer, block copolymer, gradient copolymer, or graft copolymer. Any of polymers may be used.

The molecular shape of the polymer (A) may be linear, star or dendritic. The molecular shape of the polymer (A) is preferably linear from the viewpoint of ease of molecular design.

When the radically polymerizable monomer (a) is radically polymerized in the presence of a compound having a mercapto group, the amount of the compound having a mercapto group is not particularly limited, and is calculated from the amount of the monomer used. Can be used. In general, since the number of moles of the obtained polymer is approximately equal to the number of moles of the compound having a mercapto group, the polymer obtained by adjusting the molar ratio of the monomer to be used and the compound having a mercapto group ( The polymerization degree and molecular weight of A) can be controlled. That is, the degree of polymerization (DP) of the polymer (A) is represented by the following formula when the conversion rate of the monomer (a) is 100%.
DP = number of moles of monomer (a) / number of moles of compound having a mercapto group

The number average molecular weight (Mn) of the polymer (A) can be calculated by multiplying the DP by the molecular weight of the monomer (a). When the conversion rate of the monomer (a) is less than 100%, it can be calculated by multiplying the value calculated by assuming the conversion rate as 100% by the conversion rate of the monomer (a).

The weight average molecular weight (Mw) of the polymer (A) is not particularly limited, but from the viewpoint of setting the weight average molecular weight (Mw) of the finally obtained silicone-containing block copolymer to a desired value, it is 1,000 to 50,000. It is preferably in the range, and particularly preferably in the range of 1000 to 25000.

The molecular weight distribution of the polymer (A) [the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) (Mw / Mn)] is not particularly limited, but the finally obtained silicone-containing block copolymer From the viewpoint of obtaining a desired molecular weight distribution, it is preferably 3.0 or less, particularly preferably 2.0 or less.

In the present specification, the average molecular weight is a value obtained by converting the retention time measured using a gel permeation chromatograph into the molecular weight of polystyrene by the retention time of standard polystyrene having a known molecular weight measured under the same conditions.

Specifically, the average molecular weight is, for example, using “HLC-8120GPC” (trade name, manufactured by Tosoh Corporation) as a gel permeation chromatograph apparatus, one “TSKgel G4000HXL” as a column, and “TSKgel G3000HXL”. ”And two“ TSKgel G2000HXL ”(trade name, all manufactured by Tosoh Corporation), using a differential refractometer as the detector, mobile phase: tetrahydrofuran, measurement temperature : Measured under conditions of 40 ° C. and flow rate: 1 mL / min.

[Silicone polymer (B)]
The silicone polymer (B), which is a constituent component of the silicone-containing block copolymer of the present invention, is a polyfunctional organopolysiloxane, has at least two functional groups in one molecule, and has a main chain. The polymer has a structure represented by — (Si—O) n— (n is an integer of 1 or more).

The silicone polymer (B) may have a functional group at either the terminal or the side chain of the polymer molecule.
From the viewpoint of the ease of reaction to form a block copolymer by binding to the polymer (A), it is preferable to have a functional group at the terminal of the polymer molecule.

Examples of the silicone polymer (B) include polymers having the following siloxane polymers in the main chain structure and having functional groups.
Siloxane polymers: poly (dimethylsiloxane), poly (diethylsiloxane), poly (diphenylsiloxane), poly (methylphenylsiloxane), poly (methylethylsiloxane), poly (ethylphenylsiloxane), poly (methyl-trifluoroethyl- Siloxane), poly (methyl-pentafluoropropyl-siloxane), (dimethylsiloxane-diphenylsiloxane) copolymer, (dimethylsiloxane-methylphenylsiloxane) copolymer, (dimethylsiloxane-diethylsiloxane) copolymer, and the like.

The functional group in the silicone polymer (B) is a reactive functional group Z (hydroxyl group, carboxyl group) produced by the compound represented by the structural formula Z—R—SH having the mercapto group in the polymer (A). A reactive functional group selected from the group consisting of a group and an amino group) to bond the polymer (A) and the silicone polymer (B) to each other. Therefore, the functional group is a functional group having reactivity with any of a hydroxyl group, a carboxyl group, and an amino group.

Examples of the functional group having reactivity with the hydroxyl group include an isocyanato group, an epoxy group, a carboxyl group, a carboxylic acid anhydride group, an alkoxysilyl group, and an alkoxymethyl group.

Examples of the functional group having reactivity with a carboxyl group include an epoxy group, a hydroxyl group, an isocyanato group, and an amino group.

Examples of the functional group having reactivity with an amino group include an epoxy group, a carboxyl group, and a carboxylic anhydride group.

In terms of obtaining an industrially useful block copolymer, the functional group is preferably present at the terminal of the silicone polymer (B), and the silicone polymer (B) is linear. Is particularly preferably present at both ends.

As the main chain structure of the silicone-based polymer (B), poly (diorganosiloxane) is preferable and poly (dimethylsiloxane) is particularly preferable from the viewpoints of cost and availability.

The silicone-based polymer (B) is preferably one having the above functional group at the terminal in that a block copolymer can be obtained when combined with the polymer (A). In particular, when an ABA type triblock copolymer is obtained by bonding with the polymer (A), the silicone polymer (B) has a linear poly (diorganosiloxane) having functional groups at both ends. In particular, from the viewpoint of cost and availability, linear poly (dimethylsiloxane) having functional groups at both ends is preferable.

The weight average molecular weight (Mw) of the silicone polymer (B) is not particularly limited. From the viewpoint of setting the weight average molecular weight (Mw) of the finally obtained silicone-containing block copolymer to a desired value, 100 to 50,000. Is preferably in the range of 250 to 25000.

The molecular weight distribution of the silicone polymer (B) [the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) (Mw / Mn)] is not particularly limited, but the finally obtained silicone-containing block copolymer From the viewpoint of setting the molecular weight distribution of the coalescence to a desired value, it is preferably 5.0 or less, and particularly preferably 3.0 or less.

[Silicone-containing block copolymer]
The silicone-containing block copolymer of the present invention comprises a polymer (A) and a silicone-based polymer (B) made of a polymer (A) from a compound represented by the structural formula Z—R—SH having a mercapto group. ) Reactive functional group Z (functional group selected from the group consisting of hydroxyl group, carboxyl group, amino group) and reactive functional group Z in silicone polymer (B). It can be obtained by reacting and bonding the functional group it has.

The composition ratio of the polymer (A) and the silicone-based polymer (B) constituting the silicone-containing block copolymer is preferably 5 to 90% by mass for (A) and 95 to 10% by mass for (B). Preferably, (A) is 10 to 85% by mass, (B) is 90 to 15% by mass, even more preferably (A) is 15 to 80% by mass, and (B) is 85 to 20% by mass.

When the proportion of the polymer (A) is less than 5% by mass, the polymerizability and uniformity of the silicone-containing block copolymer may be lowered. When the proportion of the polymer (B) is less than 10% by mass, the silicone The silicone-derived performance of the containing block copolymer may be reduced.

The weight-average molecular weight of the silicone-containing block copolymer is from 1,000 to 100,000, preferably from 1,000 to 75,000, particularly preferably from 1,000 to 50,000, from the viewpoint of polymerizability.

Specific examples of the combination of the functional groups to be reacted include the following.
1. 1. Carboxyl group in polymer (A) and epoxy group in silicone polymer (B) 2. Hydroxyl group in polymer (A) and isocyanato group in silicone polymer (B) The method using one combination of the above 1 to 3 hydroxyl groups in the polymer (A) and the alkoxysilyl groups in the silicone polymer (B) will be specifically described below.

In the method using the combination 1 above, in the synthesis of the polymer (A), a compound in which Z in the structural formula Z—R—SH is a carboxyl group is used as the compound having a mercapto group. The compound having such a mercapto group is not particularly limited, and specific examples include thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, 3-mercaptoisobutyric acid, 2-mercaptobenzoic acid, and the like. Can do. These can be used alone or in combination. Of these compounds having a carboxyl group and a mercapto group, 2-mercaptopropionic acid and 3-mercaptopropionic acid can be preferably used from the viewpoint of polymerizability and versatility.

A carboxyl group can be introduced into the polymer (A) by using a compound having the above carboxyl group and having a mercapto group. The resulting polymer (A) containing a carboxyl group is reacted with an epoxy group-containing silicone polymer as a silicone polymer (B).

The silicone-based polymer (B) having an epoxy group is not particularly limited. When an ABA type triblock copolymer is obtained by this method, a silicone polymer having epoxy groups at both ends can be suitably used.

The silicone polymer having an epoxy group at both ends is not particularly limited. For example, it is obtained by adding an unsaturated compound containing an epoxy group to a silicone compound containing a hydrosilyl group at both ends by a hydrosilylation reaction. Can be mentioned.

The silicone compound containing hydrosilyl groups at both ends is not particularly limited, and examples thereof include polydimethylsiloxane compounds having hydrosilyl groups at both ends.

The unsaturated compound containing an epoxy group is not particularly limited. For example, allyl glycidyl ether, glycidyl (meth) acrylate, α-ethylglycidyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate glycidyl ether, Aliphatic epoxy group-containing unsaturated compounds such as glycidyl ether glycidyl crotonate, glycidyl isocrotonate, crotonyl glycidyl ether, itaconic acid monoalkyl monoglycidyl ester, fumaric acid monoalkyl monoglycidyl ester, maleic acid monoalkyl monoglycidyl ester, 3,4-epoxycyclohexylmethyl (meth) acrylate, 2- (3,4-epoxycyclohexyl) ethyl (meth) acrylate, 2,3-epoxycyclopentylme And cycloaliphatic epoxy group-containing unsaturated compounds such as ru (meth) acrylate, 7,8-epoxy [tricyclo [5.2.1.0] dec-2-yl] oxymethyl (meth) acrylate, and the like. it can. These can be used alone or in combination. Among these, an aliphatic epoxy group-containing unsaturated compound is preferable from the viewpoint of versatility, and allyl glycidyl ether is particularly preferable from the viewpoints of polymerizability and post-treatment.

The carboxyl group in the polymer (A) and the epoxy group in the silicone polymer (B) react and bind to each other to couple the polymer (A) and the silicone polymer (B). be able to. A catalyst that promotes the reaction between the carboxyl group and the epoxy group can be used as necessary.

Specific examples of the catalyst include onium salts. An onium salt is a compound in which protons or other cations are coordinated to these lone electron pairs in a compound containing an element having a lone electron pair such as nitrogen, phosphorus, sulfur, and the like. Examples thereof include ammonium salts, quaternary phosphonium salts, and tertiary sulfonium salts.

Examples of onium salts include tetraethylammonium chloride, tetraethylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium bromide, diethyldibutylammonium bromide, dimethyldioleylammonium chloride, dimethylbenzyllaurylammonium chloride, dimethyldicyclohexylammonium bromide, tetraethylphosphonium chloride. Tetraethylphosphonium bromide, tetrabutylphosphonium chloride, dimethylbenzyl laurylphosphonium bromide, triethylsulfonium chloride and the like.

From the viewpoint of improving the yield of the coupling reaction, the epoxy group in the silicone-based polymer (B) is 0.5 to 1.1 mol, particularly preferably about 0.1 mol relative to 1 mol of the carboxyl group in the polymer (A). It is preferable to carry out the reaction so that the ratio is 6 mol to 1.0 mol, more particularly 0.7 mol to 0.9 mol.

The silicone-containing block copolymer of the present invention is useful as a silicone-based additive such as a surface conditioner or antifoaming agent for paints.

Hereinafter, the present invention will be described more specifically with reference to production examples and examples. However, the present invention is not limited to these. In each example, “parts” and “%” are based on mass unless otherwise specified.

[Production Example 1] (Synthesis of acrylic resin 1 having a carboxyl group)
A 1000 ml reactor equipped with a stirrer, a thermometer, a nitrogen gas inlet tube, and a reflux condenser was charged with 241.2 g of methyl isobutyl ketone and 3.6 g of mercaptopropionic acid, purged with nitrogen, and heated to 100 ° C. . After heating, 334.8 g of n-butyl acrylate, 10.8 g of 2,2′-azobis (2-methylbutyronitrile) and 7.2 g of methyl isobutyl ketone, 21.6 g of mercaptopropionic acid and methyl isobutyl ketone 72.0 g of the mixed solution was separated and dropped over 3 hours and kept warm for 30 minutes.

After incubation, a mixture of 3.6 g of 2,2′-azobis (2-methylbutyronitrile) and 39.6 g of methyl isobutyl ketone was added dropwise over 30 minutes, and the mixture was further incubated for 30 minutes, with the carboxyl group at one end. Polybutyl acrylate having was obtained. According to GPC measurement, the acrylic resin 1 (polybutyl acrylate) having a carboxyl group had a weight average molecular weight (Mw) of 2740, a number average molecular weight (Mn) of 1440, and Mw / Mn of 1.90.

[Production Example 2] (Synthesis of acrylic resin 2 having a carboxyl group)
A 1000 ml reactor equipped with a stirrer, a thermometer, a nitrogen gas inlet tube, and a reflux condenser was charged with 241.2 g of toluene and 3.6 g of mercaptopropionic acid, and the system was purged with nitrogen and heated to 100 ° C. After heating, 334.8 g of methyl methacrylate, 10.8 g of 2,2′-azobis (2-methylbutyronitrile) and 7.2 g of toluene, and 21.6 g of mercaptopropionic acid and 72.0 g of toluene Was separated and dripped over 3 hours and kept warm for 30 minutes.

After incubation, a mixture of 3.6 g of 2,2′-azobis (2-methylbutyronitrile) and 39.6 g of methyl isobutyl ketone was added dropwise over 30 minutes, and the mixture was further incubated for 30 minutes, with the carboxyl group at one end. Polymethylmethacrylate having was obtained. According to GPC measurement, the acrylic resin 2 (polymethyl methacrylate) having a carboxyl group had a weight average molecular weight (Mw) of 2100, a number average molecular weight (Mn) of 1220, and Mw / Mn of 1.72.

[Production Example 3] (Synthesis of silicone polymer 1 having an epoxy group)
In a 100 ml reactor equipped with a stirrer, a thermometer, a nitrogen gas introduction tube, and a reflux condenser, 42.0 g of polydimethylsiloxane having a weight average molecular weight of 1400 and hydrosilyl groups at both ends (Modifier 1449, manufactured by BRB, Netherlands) The glycidyl ether 8.2g was prepared, the inside of a system was substituted by nitrogen, and it heated at 115 degreeC. After heating, 0.1 g of chloroplatinic acid isopropanol solution (1% by mass) was added dropwise, and the mixture was kept warm for 3 hours. ^{From the 1} H-NMR spectrum, it was confirmed that the peak of 5 to 6 ppm of allyl group and the signal of 4.6 ppm of SiH disappeared, and a silicone polymer 1 having an epoxy group was obtained. According to GPC measurement, the silicone-based polymer 1 having this epoxy group had a weight average molecular weight (Mw) of 2210, a number average molecular weight (Mn) of 1200, and Mw / Mn of 1.84.

[Example 1] (Synthesis of silicone-containing block copolymer 1)
In a 100 ml reactor equipped with a stirrer, a thermometer, a nitrogen gas inlet tube, and a reflux condenser, acrylic resin 1 (22.4 g) having a carboxyl group obtained in Production Example 1 and 0.48 g of tetrabutylammonium bromide were added. The system was charged and the system was purged with nitrogen, and heated to 110 ° C. After heating, the silicone-based polymer 1 (5.2 g) having an epoxy group obtained in Production Example 3 was dropped, and after keeping the temperature for 5 hours, a solution of the silicone-containing block copolymer 1 (acryl-modified silicone compound 1) was added. Obtained. According to GPC measurement, this silicone-containing block copolymer 1 had a weight average molecular weight (Mw) of 5270, a number average molecular weight (Mn) of 2250, and Mw / Mn of 2.34.

[Example 2] (Synthesis of silicone-containing block copolymer 2)
Into a 100 ml reactor equipped with a stirrer, a thermometer, a nitrogen gas inlet tube, and a reflux condenser, acrylic resin 2 (22.4 g) having a carboxyl group obtained in Production Example 2 and 0.48 g of tetrabutylammonium bromide were added. The system was charged and the system was purged with nitrogen, and heated to 110 ° C. After heating, a mixed liquid of the silicone polymer 1 (5.2 g) having an epoxy group obtained in Production Example 3 and 13.6 g of methyl isobutyl ketone was dropped, and after keeping the temperature for 5 hours, the silicone-containing block copolymer 2 was heated. A solution of (acrylic modified silicone compound 2) was obtained. According to GPC measurement, this silicone-containing block copolymer 2 had a weight average molecular weight (Mw) of 4750, a number average molecular weight (Mn) of 2140, and Mw / Mn of 2.22.

Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. This application is based on a Japanese patent application filed on June 15, 2018 (Japanese Patent Application No. 2018-114703), the contents of which are incorporated herein by reference.

It is possible to provide a silicone-containing block copolymer that can be synthesized by a simple method at a low production cost.

Claims

A polymer (A) obtained by radical polymerization of a monomer (a) capable of radical polymerization in the presence of a compound having a mercapto group and a silicone polymer (B), which are obtained by bonding to each other; A silicone-containing block copolymer,
The monomer (a) is at least one compound selected from the group consisting of methacrylic acid esters, acrylic acid esters, aromatic alkenyls, methacrylic acid amides, and acrylic acid amide compounds;
The compound having the mercapto group has the structural formula Z—R—SH [wherein R is a divalent organic group selected from the group consisting of an alkylene group, an arylene group and an aralkylene group (the hydrogen atom of the organic group is a heteroatom) And Z is a reactive functional group selected from the group consisting of hydroxyl, carboxyl and amino groups. And a compound represented by
The silicone polymer (B) is a polyfunctional organopolysiloxane.
A silicone-containing block copolymer having a weight average molecular weight of 1,000 to 100,000.
The silicone-containing block copolymer according to claim 1, wherein the polymer (A) is a polymer having a carboxyl group, and the silicone-based polymer (B) is a polymer having an epoxy group.
The silicone according to claim 1 or 2, wherein the silicone polymer (B) is a compound obtained by adding an unsaturated compound containing an epoxy group to a silicone compound containing a hydrosilyl group at both ends. Containing block copolymer.
4. The alkylene group according to claim 1, wherein the alkylene group has 1 to 20 carbon atoms, the arylene group has 5 to 14 carbon atoms, and the aralkylene group has 7 to 11 carbon atoms. Silicone-containing block copolymer.