JP6932502B2 - Method for Producing Oxazoline-Containing Polymer - Google Patents

Description

The present invention relates to a method for producing an oxazoline-containing polymer.

Polymers containing an oxazoline group are used in various applications by utilizing the high reactivity of the oxazoline group and the like.

For example, Japanese Patent Application Laid-Open No. 2-60941 (Patent Document 1) discloses a technique for incorporating a polymer having an oxazoline group into a coating layer of a surface-coated polyester film having excellent adhesiveness, water resistance, and the like. ..

Further, in Japanese Patent Application Laid-Open No. 2000-154214 (Patent Document 2), a polymer containing a cyclic imino ether group such as an oxazoline group is put into practical use as a polymer cross-linking agent, a polymer compatibilizer and the like. It is stated that.

Such an oxazoline-containing polymer is usually obtained by polymerizing a polymerization component containing an oxazoline group-containing monomer, but from the viewpoint of crosslinkability and the like, the proportion of the oxazoline group-containing monomer in the polymerization component should be increased. Attempts are also being made.

For example, Japanese Patent Application Laid-Open No. 2013-72002 (Patent Document 3) states that a monomer component containing 40% by mass or more of an oxazoline group-containing monomer is polymerized in the presence of a mixed solvent of an organic solvent and water. When producing an oxazoline group-containing polymer, a monohydric aliphatic alcohol having 1 to 4 carbon atoms which may have an alkoxy group having 1 to 3 carbon atoms is used as the organic solvent, and the mixed solvent is used. By adjusting the content of the organic solvent to 10 to 65% by mass, it is difficult to increase the viscosity even if the solid content of the oxazoline group-containing polymer is high, and the productivity of the oxazoline group-containing polymer can be improved. The technology to be used is disclosed.

Japanese Patent Application Laid-Open No. 2-60941 (Claims) Japanese Unexamined Patent Publication No. 2000-154214 (Claims, paragraph [0002]) Japanese Unexamined Patent Publication No. 2013-72002 (Claims, paragraph [0006])

An object of the present invention is to provide a novel method for producing an oxazoline-containing polymer (polymer containing an oxazoline group).

Another object of the present invention is to provide a method for producing an oxazoline-containing polymer capable of preventing or suppressing coloration.

Another object of the present invention is to provide a method for producing an oxazoline-containing polymer that can prevent or suppress coloring even when added to an additive component.

Another object of the present invention is to provide a method for producing an oxazoline polymer having excellent storage stability.

Another object of the present invention is to provide a method for stably producing an oxazoline polymer without impairing production stability.

Another object of the present invention is to provide a method for producing an oxazoline-containing polymer capable of achieving the above effects even if the content ratio of the oxazoline-based monomer (monomer containing an oxazoline group) in the polymerization component is increased. be.

According to the studies by the present inventors, when an attempt is made to polymerize a polymerization component containing an oxazoline-based monomer, inconveniences such as coloring may occur, and this tendency particularly increases the proportion of the oxazoline-based monomer in the polymerization component. It turned out that it became stronger. It should be noted that Patent Document 3 describes that it is difficult to increase the viscosity even if the solid content of the oxazoline group-containing polymer is high, but the relationship between the viscosity and the coloring is unknown.

Under these circumstances, the present inventors have conducted intensive studies to solve the above problems, and as a result, among the raw materials and conditions for polymerization, in particular, by using a polymerization initiator as a specific polymerization initiator, oxazoline is contained. It has been found that the coloring of the polymer can be efficiently suppressed.

In addition to the above, the present inventors have obtained various new findings as described below, and have completed the present invention through further diligent studies.

That is, the present invention contains oxazoline, which polymerizes (or at least includes a polymerization step of polymerizing) a polymerization component containing an oxazoline-based monomer in the presence of an organic peroxide having a skeleton represented by the following formula (1). This is a method for producing a polymer.
ROO- (1)
(In the formula, R represents an aliphatic hydrocarbon group having 5 or more carbon atoms.)

In the above formula (1), R may be an alkyl group (for example, a tertiary alkyl group having 5 to 8 carbon atoms).

The 1-hour half-life temperature of the organic peroxide may be, for example, about 70 to 120 ° C.

In the method of the present invention, the proportion of the oxazoline-based monomer may be, for example, 15% by mass or more with respect to the total polymerization component.

Further, in the method of the present invention, polymerization may be carried out at a polymerization component concentration of 30% by mass or more (polymerization component concentration in the polymerization system).

The polymerization component may contain other monomers. In a typical method of the present invention, the polymerization component further contains a styrene-based monomer, the proportion of the oxazoline-based monomer is 40% by mass or more with respect to the entire polymerization component, and the polymerization is carried out at a polymerization component concentration of 40% by mass or more. You may.

The present invention includes an oxazoline-containing polymer (an oxazoline-containing polymer containing an oxazoline-based monomer as a polymerization component). Such an oxazoline-containing polymer is not particularly limited, but may be produced by the above method. In such an oxazoline-containing polymer, the ratio of the oxazoline-based monomer to the total polymerization component may be 15% by mass or more, and the molecular weight distribution may be 7 or less.

The oxazoline-containing polymer can be used for various purposes, and can be particularly preferably used as an additive for resins. Therefore, the present invention also includes a resin additive composed of an oxazoline-containing polymer. Such an additive may be, for example, for suppressing hydrolysis (for example, for suppressing hydrolysis of a polyester resin).

The present invention can provide a novel method for producing an oxazoline-containing polymer. In such a method of the present invention, for example, the following effects can be obtained.

In the method of the present invention, coloring of the obtained oxazoline-containing polymer can be prevented or suppressed even when the oxazoline-based monomer is used as a polymerization component.

The oxazoline-containing polymer obtained by the method of the present invention can prevent or suppress coloring even when added to an additive component (even when used as an additive). For example, even if such an oxazoline-containing polymer is added (kneaded) to a polyester resin as a hydrolysis inhibitor, coloring can be prevented or suppressed while ensuring the hydrolysis inhibitory function.
Therefore, the function of the oxazoline-containing polymer (for example, the modification function based on the oxazoline group such as the cross-linking function and the hydrolysis inhibitory function) is effectively exhibited or realized without impairing the color or appearance (product appearance) of the component to be added. can.

In the method of the present invention, an oxazoline polymer can be stably produced without impairing production stability. For example, according to the method of the present invention, even if a highly reactive oxazoline-based monomer is used as a polymerization component, an oxazoline polymer can be stably produced without increasing the molecular weight or increasing the viscosity (gelling). Further, it can be stably produced even if it is polymerized with a high-concentration polymerization component. Moreover, the molecular weight distribution of the obtained oxazoline polymer is relatively narrow.

The oxazoline polymer obtained by the method of the present invention has excellent storage stability. For example, the oxazoline polymer may be colored or increased in molecular weight (high viscosity) after polymerization. Especially in a high concentration (for example, 40% or more) polymerized component solution, the tendency of increasing the viscosity becomes strong. According to the present invention, such post-polymerization coloring and high viscosity can be efficiently suppressed.

Further, the method of the present invention can obtain the above-mentioned excellent effects, and such an effect can be realized even if the content ratio of the oxazoline-based monomer in the polymerization component is increased. For example, coloring and increasing viscosity during and after polymerization are likely to occur as the proportion of the oxazoline-based monomer (or oxazoline group) in the polymerization component (or polymer) increases. According to the method, surprisingly, even in such a case, coloring, high viscosity and the like can be suppressed or prevented at a high level.

In the present invention, a polymerization component containing an oxazoline-based monomer is polymerized using a specific polymerization initiator to produce an oxazoline-containing polymer.

[Polymerization component]
The polymerization component contains an oxazoline-based monomer. The oxazoline-based monomer is not particularly limited as long as it has an oxazoline group, and known monomers (for example, the cyclic iminoether group-containing monomer described in Patent Document 2, the oxazoline group-containing monomer described in Patent Document 3, and the like). ) Can be used.

Specific examples of the oxazoline-based monomer include vinyl oxazolines {for example, vinyl oxazoline (2-vinyl-2-oxazoline, etc.), vinyl oxazoline having a substituent [for example, alkyl-vinyl oxazoline (for example, 2-vinyl-). 4-Methyl-2-oxazoline, 2-vinyl-4,4-dimethyl-2-oxazoline, 2-vinyl-4-ethyl-2-oxazoline, 2-vinyl-4-propyl-2-oxazoline, 2-vinyl- 4-Butyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-vinyl-5-ethyl-2-oxazoline, 2-vinyl-5-propyl-2-oxazoline, 2-vinyl-5- _{C 1-20} alkyl-vinyl oxazoline such as butyl-2-oxazoline, preferably C _1-10 alkyl-vinyl oxazoline, more preferably mono or di C _1-4 alkyl-vinyl oxazoline)] etc.}, Isopropenyl oxazoline Class {eg, isopropenyl oxazoline (eg 2-isopropenyl-2-oxazoline), isopropenyl oxazoline with substituents [eg, alkyl-isopropenyl oxazoline (eg 2-isopropenyl-4-methyl-2-oxazoline, etc.) 2-Isopropenyl-4,4-dimethyl-2-oxazoline, 2-isopropenyl-4-ethyl-2-oxazoline, 2-isopropenyl-4-propyl-2-oxazoline, 2-isopropenyl-4-butyl- 2-Oxazoline, 2-isopropenyl-5-methyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline, 2-isopropenyl-5-propyl-2-oxazoline, 2-isopropenyl-5- _{C 1-20} alkyl-isopropenyl oxazoline such as butyl-2-oxazoline _{, preferably C 1-10} alkyl-isopropenyl oxazoline, more preferably mono or diC _1-4 alkyl-isopropenyl oxazoline)] etc.}, Examples thereof include allyl oxazolines corresponding to these.

Among these, isopropenyl oxazolines are preferable, and 2-isopropenyl-2-oxazolines are particularly preferable.

The oxazoline-based monomers may be used alone or in combination of two or more.

The ratio of the oxazoline-based monomer can be appropriately selected depending on the use of the oxazoline-containing polymer and the like. For example, 1% by mass or more (for example, 5% by mass or more), preferably 10% by mass or more, based on the total polymerization component. More preferably, it may be 15% by mass or more.
In particular, in the present invention, the ratio of the oxazoline-based monomer to the entire polymerization component may be 20% by mass or more, preferably 30% by mass or more, more preferably 40% by mass or more (for example, 45% by mass or more), and 50. It can also be mass% or more (for example, 60% by mass or more, preferably 70% by mass or more).

The polymerization component may contain at least an oxazoline-based monomer, and may contain other monomers if necessary.

The other monomer (a monomer that does not belong to the category of the oxazoline-based monomer) can be appropriately selected depending on the use of the oxazoline-containing polymer and the like, and is not particularly limited, but for example, a styrene-based monomer [or an aromatic vinyl-based monomer, for example. , Styrene, α-alkyl styrene (eg, α-C _1-4 alkyl styrene such as α-methyl styrene), alkyl styrene (eg, C _1-4 alkyl styrene such as vinyl toluene), halo styrene (eg, chloro styrene, etc.) ), Etc.], Vinyl esters (eg, vinyl acetate, vinyl propionate, etc.), unsaturated nitriles (eg, acrylic nitrile, methacrylate, etc.), vinyl ethers (eg, methyl vinyl ether, alkyl vinyl ethers such as ethyl vinyl ether, etc.), amide groups Containing monomers [eg, (meth) acrylamide, N-substituted (meth) acrylamide (eg, N-alkyl (meth) acrylamide such as N-methyl (meth) acrylamide), etc.], olefinic monomers [eg, alkene (eg, alken) _{C 2-10} alkene such as ethylene, propylene, 1-butene, isobutylene, 1-octene)], halogen-containing monomers (eg, halo C _2-10 alkene such as vinyl chloride, vinylidene chloride, vinyl fluoride), ( Meta) Acrylic Styrene {For example, (meth) acrylic acid, (meth) acrylic acid alkyl ester [for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, (meth) Styrene acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, (meth) acrylate _{n-Hexyl, C 1-20} alkyl (meth) acrylates such as 2-ethylhexyl (meth) acrylate], Cycloalkyl (meth) acrylates [eg, (meth) acrylic acids such as cyclohexyl (meth) acrylates C _3-20 cycloalkyl, etc.], aryl (meth) acrylate [eg, C _6-20 aryl (meth) acrylate, such as phenyl (meth) acrylate], aralkyl (meth) acrylate [eg, (meth) (Meta) acrylate C _6-10 aryl C _1-4 alkyl such as benzyl acrylate], (meth) acrylic acid esthetics having a hydroxyl group [For example, hydroxyalkyl (meth) acrylate (for example, _{hydroxyC 2-10} alkyl (meth) acrylate such as 2-hydroxyethyl (meth) acrylate)], (meth) acrylic acid having an alkoxy group. Esters [eg, (eg, (meth) acrylate alkoxyalkyl (eg, (meth) acrylate C _1-10 alkoxy C _2-10 alkyl, such as (meth) acrylate 2-methoxyethyl)], glycidyl (meth) acrylate, etc. } And so on.

Other monomers may be used alone or in combination of two or more.

Among these other monomers, a styrene-based monomer may be preferably used.
According to the studies by the present inventors, it seems that coloring is easy when a styrene-based monomer is used, but in the method of the present invention, coloring can be efficiently suppressed or prevented even when such a styrene-based monomer is used as a polymerization component. Therefore, the obtained oxazoline-based polymer can be used in a wide range of applications. For example, by incorporating a styrene-based unit into an oxazoline-based polymer, it is highly compatible depending on the type of the component to be added [for example, an aromatic skeleton-containing polymer such as an aromatic polyester resin (PET, PBT, etc.)]. It can be added, and it is easy to effectively exert its function as an additive while suppressing coloring.

When the other monomer contains a styrene-based monomer, the ratio of the styrene-based monomer to the whole other monomer is, for example, 5% by mass or more (for example, 10% by mass or more), preferably 20% by mass or more (for example, 30% by mass). % Or more), more preferably 40% by mass or more (for example, 50% by mass or more), particularly preferably 60% by mass or more (for example, 70% by mass or more), and 80% by mass or more (for example, 90% by mass). % Or more).

When other monomers are used, the ratio of the oxazoline-based monomer to the other monomer is preferably, for example, the former / the latter (mass ratio) = 99/1 to 5/95 (for example, 98/2 to 10/90). May be about 97/3 to 12/88 (for example, 96/4 to 15/85), more preferably 95/5 to 18/82 (for example, 93/7 to 20/80), and is usually 99. It may be / 1 to 25/75 (for example, 98/2 to 30/70, preferably 95/5 to 40/60, more preferably 90/10 to 45/55).

[Polymerization initiator]
In the method of the present invention, an organic peroxide having a skeleton represented by the following formula (1) (hereinafter, may be simply referred to as an organic peroxide) is used as a polymerization initiator, and the polymerization component is polymerized. It is characterized by doing.

ROO- (1)
(In the formula, R represents an aliphatic hydrocarbon group having 5 or more carbon atoms.)

In R of the above formula (1), the aliphatic hydrocarbon group may be, for example, a saturated aliphatic hydrocarbon group.

The aliphatic hydrocarbon group may be a chain aliphatic hydrocarbon group (alkyl group or the like) or a cyclic aliphatic hydrocarbon group (cycloalkyl group or the like), and has a chain structure and a cyclic structure. It may be an aliphatic hydrocarbon group having a combination of (such as a cycloalkylalkyl group), or may be an aliphatic hydrocarbon group having a chain structure (particularly an alkyl group).
Further, in the aliphatic hydrocarbon group having a chain structure, the chain structure may be a linear structure or a branched chain structure.

The aliphatic hydrocarbon group may have a substituent. The substituent is not particularly limited as long as the polymerization initiation ability can be guaranteed, and for example, a hydroxyl group, an alkoxy group, an amino group, a substituent amino group, a halogen atom, an acyl group, an alkoxycarbonyl group, and a non-aliphatic hydrocarbon group ( For example, an aromatic hydrocarbon group, etc.). Substituents may be used alone or in combination of two or more. Further, it may have two or more of the same substituents.

In R of the above formula (1), the number of carbon atoms of the aliphatic hydrocarbon group may be 5 or more, for example, 5 to 30, preferably 5 to 20, and more preferably 5 to 10 (for example, 5 to 9). ), Especially about 5 to 8.

Specific R includes an alkyl group having 5 or more carbon atoms, for example, an n-pentyl group (amyl group), an isopentyl group, an s-pentyl group, a t-pentyl group, an n-hexyl group, a t-hexyl group, and t. _{C 5-20} alkyl groups such as −heptyl group, n-octyl group, 2-ethylhexyl group, t-octyl group, 1,1,3,3-tetramethylbutyl group, t-nonanyl group, t-decanyl group ( For example, a C _5-10 alkyl group, preferably a C _5-8 alkyl group) and the like can be mentioned.

Preferred R includes a branched alkyl group having 5 or more carbon atoms, and in particular, a tertiary alkyl group having 5 or more carbon atoms (or a t-alkyl group, for example, a t-pentyl group, a t-hexyl group, t- _{T-C 5-20} alkyl groups such as octyl group, 1,1,3,3-tetramethylbutyl group, t-nonanyl group, preferably t-C _5-10 alkyl group, more preferably t-C _{5- 8} alkyl group) is preferable.

The organic peroxide may have a skeleton (peroxy skeleton) represented by the above formula (1), and other structures (skeleton) are not particularly limited.
For example, as long as the organic peroxide has a skeleton represented by the above formula (1), a hydroperoxide (a compound in which one hydrogen peroxide of hydrogen peroxide is substituted with R) and a peroxide (for example, hydrogen peroxide) can be used. One hydrogen is substituted with R and the other is substituted with a hydrocarbon group), peroxymonocarbonate (for example, one hydrogen peroxide is substituted with R and the other hydrogen is an alkoxycarbonyl group). (Compound substituted with), peroxyester (for example, a compound in which one hydrogen peroxide of hydrogen peroxide is substituted with R and the other hydrogen is substituted with an acyl group), peroxyketal and the like.

Specific organic peroxides include compounds represented by the following formula (A).

ROOX (A)
{In the formula, X is a hydrogen atom, a hydrocarbon group, -COOR ¹ (in the formula, R ¹ represents a hydrocarbon group), -COR ¹ (in the formula, R ¹ represents a hydrocarbon group), or- CR ² R ³ Y [In the formula, R ² and R ³ indicate the same or different hydrocarbon groups, Y indicates −OOR ⁴ (in the formula, R ⁴ indicates a hydrocarbon group), and R ² and R ³ are Together they may form a ring. ], And R is the same as above. }

In the formula (A), as the hydrocarbon group for X and ^R 1 to R ^4, for example, aliphatic hydrocarbon group [e.g., an alkyl group (e.g., methyl group, ethyl group, n- propyl group, an isopropyl radical, n -Butyl group, s-butyl group, t-butyl group, n-pentyl group (amyl group), isopentyl group, s-pentyl group, t-pentyl group, n-hexyl group, t-hexyl group, n-heptyl group , T-Heptyl group, n-octyl group, 2-ethylhexyl group, t-octyl group, 1,1,3,3-tetramethylbutyl group, t-nonanyl group and other C _1-20 alkyl groups, preferably C _1-10 alkyl, more preferably C _1-8 alkyl group), cycloalkyl group (eg, C _3-20 cycloalkyl group such as cyclopentyl group, cyclohexyl group, preferably C _4-8 cycloalkyl group)],. _{Aromatic hydrocarbon groups [eg, C 6-20} aryl groups such as phenyl groups, trill groups, xylyl groups, naphthyl groups, preferably C _6-12 aryl groups, more preferably C _6-10 aryls. Groups), aralkyl groups (eg, C _6-10 aryl C _1-4 alkyl groups such as benzyl group and phenethyl group)] and the like. The hydrocarbon group may have a substituent (such as the substituent exemplified in the above section R).

In the above formula (A), when X is a hydrocarbon group or when X is −CR ² R ³ Y, the ^{hydrocarbon group in R 4} has 5 or more carbon atoms as in R. It may be an aliphatic hydrocarbon group (particularly, a t-alkyl group having 5 or more carbon atoms).

Further, in the above formula (A), when X is −CR ² R ³ Y and R ² and R ³ form a ring together, the ring is, for example, an aliphatic hydrocarbon ring. [For example, a cycloalkane ring (for example, a C _5-10 cycloalkane ring such as a cyclohexane ring)] can be mentioned. The aliphatic hydrocarbon ring may have a substituent similar to that of the hydrocarbon group.

Examples of the organic peroxide having a skeleton represented by the typical formula (1) include a peroxide having an aliphatic hydrocarbon group having 5 or more carbon atoms [for example, a dialkyl peroxide (for example, di-t-hexyl). _{Di C 5-20} alkyl peroxides such as peroxides, preferably di C _5-10 alkyl peroxides, more preferably di t-C _5-10 alkyl peroxides, especially di t-C _5-8 alkyl peroxides). _{Etc.], peroxymonocarbonate having an aliphatic hydrocarbon group having 5 or more carbon atoms [for example, C 5- of} alkyl peroxyalkyl carbonate (for example, t-amyl peroxyisopropyl carbonate, t-hexyl peroxyisopropyl carbonate, etc.] ₂₀ alkyl peroxy C _1-20 alkyl carbonate, preferably C _5-10 alkyl peroxy C _1-10 alkyl carbonate, more preferably t-C _5-10 alkyl peroxy C _1-10 alkyl carbonate)], carbon Peroxy ester having an aliphatic hydrocarbon group of several 5 or more [for example, alkyl peroxy alkanoate (for example, t-amyl peroxyacetate, t-amyl peroxy-2-ethylhexanoate, t-amyl peroxy) -3,5,5-trimethylhexanoate, t-hexylperoxy-2-ethylhexanoate, t-hexylperoxyneodecanoate, 1,1,3,3-tetramethylbutylperoxyacetate, _{C 5-20} alkyl peroxy C _2- such as 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate ₂₀ alkanoates, preferably C _5-10 alkylperoxy C _2-10 alkanoates, more preferably t-C _5-10 alkylperoxy C _2-10 alkanoates, alkyl peroxybenzoates (eg, t-hexyl peroxybenzoates). C _5-20 alkyl peroxybenzoate, preferably C _5-10 alkyl peroxybenzoate, more preferably t-C _5-10 alkyl peroxybenzoate), etc.], an aliphatic hydrocarbon group having 5 or more carbon atoms. Peroxyketal [eg, 1,1-di (C) such as 1,1-dialkylcycloalkane (eg, 1,1-di (t-hexylperoxy) cyclohexane) _5-20 alkyl peroxy) cycloalkanes, preferably 1,1-di (C _5-10 alkyl peroxy) cycloalkanes, more preferably 1,1-di (C _5-8 alkyl peroxy) cycloalkanes) and the like. ] And so on.

The organic peroxide may be used alone or in combination of two or more.

The decomposition activity of the organic peroxide can be appropriately selected depending on the type of the polymerization component and the like. For example, the one-hour half-life temperature of the organic peroxide is 200 ° C. or lower (for example, 30 to 180 ° C.), preferably. It may be 160 ° C. or lower (for example, 40 to 155 ° C.), more preferably 150 ° C. or lower (for example, 50 to 140 ° C.), particularly 130 ° C. or lower (for example, 60 to 125 ° C.), and usually 70 to 120 ° C. It may be about.

The proportion of the organic peroxide having a skeleton represented by the formula (1) is not particularly limited, but is, for example, 0.01 to 30 parts by mass, preferably 0.1 to 1 parts by mass with respect to 100 parts by mass of the polymerization component. It may be about 20 parts by mass, more preferably about 0.5 to 15 parts by mass (for example, 1 to 10 parts by mass).

The polymerization initiator is an organic peroxide that does not belong to the category of other polymerization initiators [for example, an organic peroxide having a skeleton represented by the formula (1), as long as the effect of the present invention is not impaired. _{(Diacyl peroxide such as benzoyl peroxide; organic peroxide having C 1-4} alkyl peroxy group such as t-butyl peroxyisopropyl carbonate, t-butyl peroxy 2-ethylhexanoate), azo system Compounds, persulfates, inorganic peroxides (such as ammonium persulfate), etc.] may be included.

[Polymerization process]
In the present invention, the polymerization component is polymerized in the presence of an organic peroxide (including a polymerization initiator) having a skeleton represented by the formula (1).

Such polymerization (polymerization step) may be carried out at least in the presence of an organic peroxide having a skeleton represented by the formula (1), and if necessary, other components (for example, a chain transfer agent, pH adjustment) may be carried out. Agents, etc.) may be present (coexist).

The polymerization may be any of bulk polymerization, solution polymerization, suspension polymerization, emulsion polymerization and the like, and in particular, solution polymerization may be used.

When the polymerization is carried out in a solvent (for example, in the case of solution polymerization), the solvent can be appropriately selected depending on the type of the polymerization component and the like, and is not particularly limited, but for example, an organic solvent [aromatic hydrocarbons (for example, aromatic hydrocarbons). , Benzene, toluene, xylene, ethylbenzene, etc.), aliphatic or alicyclic hydrocarbons (eg, cyclohexane, methylcyclohexane, etc.), halogen-based solvents (eg, chloroform, methylene chloride, carbon tetrachloride, etc.), etc.], ketones Classes (eg, acetone, methyl ethyl ketone, etc.), esters (eg, ethyl acetate, butyl acetate, etc.), ethers [eg, chain ethers (eg, diethyl ether, etc.), cyclic ethers (eg, tetrahydrofuran, dioxane, etc.) ) Etc.], amides [eg, N-substituted amides (N-alkyl substituted alcanamides such as N, N-dimethylformamide)], alcohols (eg, alkanols such as methanol, ethanol and isopropanol), glycol ethers (eg, alkanols such as methanol, ethanol and isopropanol), glycol ethers (eg. For example, alkanediol such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, diethylene glycol monoethyl ether or monoalkyl ether of polyalcandiol)], water and the like can be mentioned.
Generally, the solvent may be composed of an organic solvent (for example, aromatic hydrocarbons). Further, in the present invention, although it depends on the polymerization component, the type of oxazoline-containing polymer obtained, and the like, as in Patent Document 3, an aqueous solvent (solvent that dissolves in water) that requires high energy for desolvation (degassing). The polymerization can be carried out without using the above, that is, even when a non-aqueous solvent is used as the solvent. Therefore, it is possible to efficiently recover the oxazoline-containing polymer.

The solvent may be used alone or in combination of two or more.

In the polymerization, the concentration of the polymerization component in the whole polymerization system is, for example, 1% by mass or more (for example, 3 to 100% by mass), preferably 5% by mass or more (for example, 10 to 90% by mass), and more preferably 20% by mass. % Or more (for example, 25 to 80% by mass), particularly 30% by mass or more (for example, 35 to 70% by mass), or 40% by mass or more (for example, 45% by mass or more).

In the present invention, in the polymerization system, an oxazoline-containing polymer can be stably produced even if the concentration of the polymerization component is high.

The polymerization is usually carried out at a predetermined temperature (or under heating). Further, the polymerization may be carried out under reflux. The polymerization temperature (reaction temperature) can be appropriately selected depending on the polymerization component, the polymerization initiator, the type of solvent, etc., and is, for example, 20 ° C. or higher, preferably 30 ° C. or higher (for example, 35 to 180 ° C.), more preferably. It may be 40 ° C. or higher (for example, 45 to 170 ° C.), particularly 50 ° C. or higher (for example, 55 to 150 ° C.), particularly preferably 60 ° C. or higher (for example, 65 to 130 ° C.), and usually 70 to 120 ° C. It may be a degree.

The polymerization temperature may be changed with the progress of the polymerization, but even when the polymerization temperature is changed in this way, the polymerization is usually carried out within the above temperature range.

Each component (polymerization component, polymerization initiator, etc.) may be charged into the reactor at the stage of initiation of polymerization, or may be added as the polymerization progresses. In such a case, the addition rate of each component can be appropriately selected according to the capacity of the reactor and the like. The addition time can also be appropriately selected in the same manner.

The addition of each component may be continuous or intermittent. Further, the addition rate may be constant or may be changed.

The polymerization may be carried out under stirring. Further, the polymerization may be carried out in air or in an inert atmosphere (in nitrogen, helium, argon, etc.).

The polymerization time can be appropriately selected depending on the amount of the polymerization component, the polymerization temperature, and the like, and is not particularly limited, but is, for example, 30 minutes or more (for example, 40 minutes to 24 hours), preferably 1 hour or more (for example, 1.5 hours). ~ 16 hours), more preferably 2 hours or more (eg, 2.5-12 hours).

The polymerization is not particularly limited, and may be stopped by, for example, cooling the reaction system.

[Oxazoline-containing polymer]]
As described above, an oxazoline-containing polymer is obtained.

The oxazoline-containing polymer may be recovered by purification (demonomerization, desolvation, etc.).

The oxazoline-containing polymer is a polymer [polymer (radical polymer)] containing an oxazoline-based monomer as a polymerization component, and has a skeleton that reflects the polymerization component.
The oxazoline-containing polymer may be either a water-soluble polymer or a water-insoluble (hydrophobic) polymer depending on the type of the polymerization component, but is typically a water-insoluble polymer. There may be.

When two or more kinds of monomers are used as the polymerization component (for example, when an oxazoline-based monomer is combined with another monomer), a copolymer can be obtained. The structure of the copolymer is not particularly limited, and may be random, block, or the like.

The weight average molecular weight (Mw) of the oxazoline-containing polymer is not particularly limited and can be selected depending on the intended use, for example, 1000 or more (for example, 3000-1000000), preferably 3000 or more (for example, 5000-500000). More preferably, it may be 7,000 or more (for example, 8000 to 30000), particularly 10000 or more (for example, 12000 to 200,000), and usually about 5000 to 100,000 (for example, 1000 to 70000).

The molecular weight distribution [weight average molecular weight (Mw) / number average molecular weight (Mn)] of the oxazoline-containing polymer is, for example, 10 or less (for example, 1 to 8), preferably 7 or less (for example, 1.05 to 6). More preferably, it may be about 5 or less (for example, 1.1 to 4), or 4 or less (for example, 1.2 to 3.5). In the present invention, even if an oxazoline-based monomer is used as a polymerization component (particularly, a polymerization component containing a high proportion of an oxazoline-based monomer), an oxazoline polymer can be stably produced without increasing the molecular weight or increasing the viscosity (gelling). It is possible to obtain an oxazoline polymer having a relatively low molecular weight distribution in this way.

The oxazoline-containing polymer has an oxazoline group (oxazoline skeleton) derived from an oxazoline-based monomer, and can be used for various purposes. Such applications include, for example, a hydrolysis inhibitor [for example, a hydrolysis inhibitor of a polyester resin (for example, an aromatic polyester resin such as polybutylene terephthalate and polyethylene terephthalate)], and a cross-linking agent (cross-linking for a coating agent). Agents), modifiers (such as modifiers for industrial plastics), adhesives, etc.

The present invention is not limited to each of the above-described embodiments, and various modifications can be made, and the technical means of the present invention can also be obtained by appropriately combining the technical means disclosed in the different embodiments. Included in the range.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited by the following Examples as well as the present invention, and appropriate modifications are made to the extent that it can be adapted to the gist of the above and the following. It is also possible to carry out, all of which are within the technical scope of the invention.
In the examples, "parts" means "mass (weight) parts" unless otherwise specified.

[Example 1]
A beaker was charged with 100 parts of toluene, 50 parts of 2-isopropenyl-2-oxazoline (IPO) and 50 parts of styrene (St) to prepare a toluene mixture containing a polymerization component. Next, 40% by mass of the produced toluene mixture containing the polymerization component was put into a 2L flask equipped with a stirrer, a dropping port, a thermometer, a cooling tube and a nitrogen gas introduction tube, and nitrogen gas was put into the flask. After replacing the inside of the flask with nitrogen gas by blowing for 10 minutes, the temperature was raised to 110 ° C. while stirring the inside of the flask.
Then, the remaining 60% by mass of the produced toluene mixture containing the polymerization component was mixed with 5 parts of tert-amylperoxyisopropyl carbonate (manufactured by Kayaku Akzo Corporation, trade name: Kayacarboxylic AIC-75) as a polymerization initiator. A mixture was obtained. The obtained mixture was continuously added dropwise into the flask over 3 hours (that is, the concentration of the polymer component was 50% by mass), and then heating was continued for 5 hours to complete the reaction. Then, the contents in the flask were cooled to 25 ° C. to obtain an oxazoline-based polymer solution (polymerization solution 1) containing the polymer at a concentration of 50% by mass.

The obtained polymerization solution 1 was measured according to the following evaluation methods and criteria. The results are shown in Table 1.

[Molecular weight and molecular weight distribution]
The molecular weight and molecular weight distribution of the polymer contained in the polymerization solution were measured under the following measurement conditions.
Equipment: Made by Tosoh Corporation, Part number: HLC-8320GPC
Detector: RI
Column: TSKgel SuperMultipore HZ-M {manufactured by Tosoh Corporation}
Column temperature: 40 ° C
Flow rate: 0.18 ml / min Calibration curve: Standard polystyrene Eluent: Tetrahydrofuran containing 1% by weight of triethylamine

[Initial color]
The obtained polymer solution was visually evaluated.
[50 ° C for 1 month]
The obtained polymer solution was stored in a glass container in an oven at 50 ° C. for 1 month and evaluated visually.

[Initial viscosity value]
The viscosity (mPa · s) of the obtained polymer solution at 25 ° C. was measured with a B-type viscometer.

[50 ° C. 1 month viscosity value]
The obtained polymer solution was stored in a glass container in an oven at 50 ° C. for 1 month, and then the viscosity (mPa · s) at 25 ° C. was measured with a B-type viscometer.

[Viscosity increase rate]
Viscosity increase rate = 50 ° C. 1 month viscosity value / initial viscosity value.

Next, the obtained polymer solution (1) was added little by little in a beaker containing hexane to precipitate a polymer, and the polymer was taken out by filtration. Then, the solvent was completely volatilized at a temperature of 100 ° C. for 10 hours to obtain a polymer (1) having an oxazoline group.

Next, the obtained polymer (1) was used as a hydrolysis inhibitor for polyester resins.

Polybutylene terephthalate [manufactured by Mitsubishi Engineering Plastics Co., Ltd., trade name: Novaduran (registered trademark) 5010R3-2] After melting 99 parts at 250 ° C. with a lab mixer, one part of the polymer (1) is added to the polybutylene terephthalate. Was added and kneaded for 10 minutes to obtain a polyester resin composition (1).
The obtained polyester resin composition (1) is heated to a temperature equal to or higher than the softening point and pressed on a flat plate to prepare a sheet having a thickness of 300 μm, and a strip-shaped sheet having a width of 10 mm and a length of 80 mm is cut out from the sheet. As a result, an evaluation sheet was prepared, and measurements were made according to the following evaluation methods and criteria. The results are shown in Table 1.

[Colorability]
Coloring occurs using an evaluation sheet prepared only with polybutylene terephthalate [manufactured by Mitsubishi Engineering Plastics Co., Ltd., trade name: Novaduran (registered trademark) 5010R3-2] (without using a polymer having an oxazoline group) as a reference color. It was evaluated by the presence or absence.
○: No coloring ×: Colored

[Inhibition of hydrolysis]
Using a tensile tester [manufactured by Shimadzu Corporation, trade name: Autograph AG-1kNI SP], the tensile strength of the evaluation sheet obtained above was 5 at a tensile speed of 10 mm / min in accordance with ISO527. The measurement was performed once, and the average value A of the tensile strength was calculated. Next, an evaluation sheet different from the evaluation sheet whose tensile strength was measured above was placed in an advanced accelerated life tester [ESPEC Co., Ltd., trade name: HAST CHAMBER EHS-210M], and the temperature was 121 ° C., relative to each other. Under the condition of 100% humidity, 50 hours or 100 hours after the start of the highly accelerated life test, the evaluation sheet is taken out, and the tensile strength of the evaluation sheet is adjusted to the same as above by using the tensile tester. The measurement was performed 5 times, and the average value B of the tensile strength was calculated.

From the average value calculated above, the strength retention rate (%) is expressed by the formula:
[Strength retention rate (%)] = ([Average value of tensile strength B] ÷ [Average value of tensile strength A]) × 100
The hydrolysis resistance was evaluated based on the following evaluation criteria.

The polyester resin composition is more excellent in hydrolysis resistance as the strength retention rate (%) is closer to 100% after 50 hours and 100 hours have passed since the start of the highly accelerated life test. In order to make the polyester resin composition practical as a material for parts used under high temperature and humidity such as automobile engine parts, the strength retention rate (%) is particularly preferably 100%. ..

(Evaluation criteria)
100 points: Strength retention rate is 95% or more and 80 points: Strength retention rate is 80% or more and less than 95% 50 points: Strength retention rate is 70% or more and less than 80% 30 points: Strength retention rate is 50% or more and less than 70% 0 Point: Strength retention rate is less than 50%

[Examples 2 to 11, Reference Examples 1 to 4]
In Example 1, as shown in Tables 1 and 2, various conditions (type of polymerization initiator, ratio of styrene to 2-isopropenyl-2-oxazoline, solvent type and amount used thereof, polymerization temperature, etc.) were set. A polymer solution and a polymer were obtained in the same manner as in Example 1 except that they were changed, and various measurements and evaluations were performed.
In Reference Example 1, the molecular weight and viscosity could not be measured because of gelation.

The results are shown in Tables 1 and 2.

In Tables 1 and 2, the types (abbreviations) of the polymerization initiators are as follows.

AIC-75: t-amylperoxyisopropyl carbonate Trade name; Kayacarboxylic AIC-75 (manufactured by Kayaku Akzo Corporation)
AN: t-amylperoxy-3,5,5-trimethylhexanoate Brand name; Kayaester AN (manufactured by Kayaku Akzo Corporation)
I: t-hexyl peroxyisopropyl carbonate Product name; Perhexyl I (manufactured by NOF CORPORATION)
BIC-75: t-Butylperoxyisopropyl carbonate Brand name; Kayacarboxylic BIC-75 (manufactured by Kayaku Akzo Corporation)
Tori 121: t-amylperoxy-2-ethylhexanoate Brand name; Trigonox 121 (manufactured by Kayaku Akzo Corporation)
Perocta O: 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate Brand name; Perocta O (manufactured by NOF CORPORATION)
Perbutyl O: t-butyl peroxy-2-ethylhexanoate Brand name; Perbutyl O (manufactured by NOF CORPORATION)
AIBN: 2,2-azobis (isobutyronitrile)
HC: 1,1-di (t-hexyl peroxy) cyclohexane Trade name; Perhexa HC (manufactured by NOF CORPORATION)
D: Di-t-hexyl peroxide Trade name; Perhexyl D (NOF CORPORATION)
Perhexyl O: t-hexyl peroxy-2-ethylhexanoate Brand name; Perhexyl O (NOF CORPORATION)

As is clear from the above table, in the examples, the oxazoline-containing polymer with less coloring could be stably produced.
It was also found that the oxazoline-containing polymer obtained in the examples had no noticeable change in color and viscosity and was excellent in storage stability not only in the initial stage but also after treatment at 50 ° C. for 1 month. ..
Further, the oxazoline-containing polymer obtained in the examples does not cause coloring even when added to the polyester resin serving as the base resin, and can efficiently exert its function (hydrolysis inhibitory effect) without coloring. rice field.

According to the present invention, it is possible to provide a novel polymerization method of an oxazoline-based monomer. Such a polymerization method is extremely industrially useful, for example, an oxazoline-containing polymer having less coloring and excellent storage stability can be obtained even when an oxazoline-based monomer is used as a polymerization component.

Claims (9)

A method for producing an oxazoline-containing polymer, which polymerizes a polymerization component containing an oxazoline-based monomer in the presence of an organic peroxide having a skeleton represented by the following formula (1).
ROO- (1)
(In the formula, R represents an aliphatic hydrocarbon group having 5 or more carbon atoms.) The production method according to claim 1, wherein in R of the formula (1), the aliphatic hydrocarbon group is a saturated aliphatic hydrocarbon group. R of formula (1) is n-pentyl group, isopentyl group, s-pentyl group, t-pentyl group, n-hexyl group, t-hexyl group, t-heptyl group, n-octyl group, 2-ethylhexyl group. The production method according to claim 1 or 2, wherein the t-octyl group, 1,1,3,3-tetramethylbutyl group, t-nonanyl group, or t-decanyl group. The production method according to any one of claims 1 to 3, wherein R in the formula (1) is a tertiary alkyl group having 5 or more carbon atoms. The organic peroxide having a skeleton represented by the formula (1) is a peroxide having an aliphatic hydrocarbon group having 5 or more carbon atoms, a peroxymonocarbonate having an aliphatic hydrocarbon group having 5 or more carbon atoms, and carbon. The production method according to any one of claims 1 to 4, which is at least one selected from peroxyesters having an aliphatic hydrocarbon group of several 5 or more. The production method according to any one of claims 1 to 5, wherein the proportion of the oxazoline-based monomer is 15% by mass or more based on the total polymerization component. The production method according to any one of claims 1 to 6, wherein polymerization is carried out at a polymerization component concentration of 30% by mass or more. Any of claims 1 to 7, wherein the polymerization component further contains a styrene-based monomer, the proportion of the oxazoline-based monomer is 40% by mass or more with respect to the total polymerization component, and the polymerization is carried out at a polymerization component concentration of 40% by mass or more. The manufacturing method described in Crab. The production method according to any one of claims 1 to 8, wherein the viscosity increase rate of the polymerization solution containing the oxazoline-containing polymer is 1.1 to 1.4.
However, the viscosity increase rate is defined below.
Viscosity increase rate = 50 ° C for 1 month Viscosity value / Initial viscosity value
Initial viscosity value: Viscosity (mPa · s) of the polymer solution at 25 ° C. as measured by a B-type viscometer.
50 ° C for 1 month Viscosity value:
The viscosity (mPa · s) of the polymer solution at 25 ° C. measured by a B-type viscometer after being stored in a glass container in a 50 ° C. oven for 1 month .