JP2023135158A - Polymer and dental adhesive composition using the same - Google Patents

Abstract

To provide a polymer which does not need to be cured at a stage before a filling material is charged, is easily cured, and can be applied to various filling materials, and to provide a dental adhesive composition containing the polymer.SOLUTION: The polymer includes: 5 to 80 mol% of a structural unit (X) that is derived from a (meth)acrylic monomer having a radically polymerizable unsaturated group; 15 to 90 mol% of a structural unit (Y) that is derived from a (meth)acrylic monomer having an alkyl group; and 5 to 50 mol% of a structural unit (Z) that is derived from a (meth)acrylic monomer containing an acidic group, each of which is represented by a specific general formula. The structural unit (X) improves the adhesiveness to the filling material; the structural unit (Z) improves the adhesiveness to a tooth substance; and the structural unit (Y) improves the compatibility with the tooth substance and the filling material, and improves the permeability to a tooth surface and the compatibility with the filling material. Thereby, the dental adhesive composition including the polymer according to one embodiment of the present invention exhibits high adhesiveness to the tooth surface and the filling material.SELECTED DRAWING: Figure 1

Description

The present invention relates to polymers having adhesive properties and dental adhesive compositions.

A hardening filling material called composite resin is used to repair teeth damaged by caries or the like. Such filling materials have almost no adhesion to the tooth structure that constitutes the tooth. For this reason, the filling material is usually bonded to the tooth structure via an adhesive. Typical adhesives need to be cured in advance to obtain high adhesive strength.

As an adhesive that can be used to bond filler materials, a photocurable adhesive that can be cured by light irradiation is known (see, for example, Patent Document 1). The photocurable adhesive needs to be cured by light irradiation within the oral cavity before filling with the filling material. In order to cure the photocurable adhesive, light irradiation for several seconds to several tens of seconds is required.

For this reason, photocurable adhesives place a greater burden on patients due to longer treatment times and heat generation associated with light irradiation. Furthermore, since the photocurable adhesive is exposed in the oral cavity when irradiated with light, it may be contaminated by patient's saliva or blood. Therefore, there is a need for an adhesive that does not require light irradiation before filling with the filler material.

Patent Document 2 discloses an adhesive that does not require curing by light irradiation. This adhesive is a two-component type, that is, it is configured such that chemical polymerization type curing progresses by mixing the first agent and the second agent. However, with this adhesive, it takes effort to mix the first agent and the second agent during treatment and time to harden them.

Further, Patent Document 3 discloses a one-component dental adhesive that does not require light irradiation. In this adhesive, after filling with the filler material, photopolymerization type curing progresses due to the light irradiated during curing of the filler material, and aromatic amine is supplied from the filler material, resulting in chemical polymerization type adhesive. As the curing progresses, there is no need to provide additional time for curing the adhesive. However, this adhesive cannot be applied to filler materials other than those containing aromatic amines.

JP2009-137960A JP2018-027913A JP2020-138911A

Therefore, in order to achieve dental treatment quickly and with less burden on the patient, we need an adhesive that can be easily cured, does not require light irradiation before filling the filling material, and can be used for general purposes. Desired. However, at present, the only known adhesives with such a configuration are those that are not compatible with general-purpose filler materials.

In view of the above circumstances, an object of the present invention is to provide a polymer and a dental adhesive composition containing the polymer that can be easily cured without requiring curing at a stage before filling the filling material, and that can be applied to various filling materials. It's about providing things.

In order to achieve the above object, a polymer according to an embodiment of the present invention contains 5 to 80 mol% of a structural unit (X) represented by the following general formula (1) and a structure represented by the following general formula (2). It contains 15 to 90 mol% of the unit (Y) and 5 to 50 mol% of the structural unit (Z) represented by the following general formula (3).
(In general formula (1), R ¹ and R ² represent a hydrogen atom or a methyl group, and n represents an integer of 1 to 15.)
(In general formula (2), R ³ represents a hydrogen atom or a methyl group, and R ⁴ represents a group having a total carbon number of 1 to 15 represented by the following general formula (2-1).)
(In the above formula, p represents an integer from 0 to 5, and R ^' represents an alkyl group.)
(In general formula (3), R ⁵ represents a hydrogen atom or a methyl group, and L represents a dihydrogen phosphate monoester group {-O-P(=O)(OH) ₂ } or a phosphono group {-P( =O)(OH) ₂ }, m represents an integer from 1 to 15.)

The polymer according to one embodiment of the present invention has a radically polymerizable unsaturated group and is used for a radically polymerizable adhesive.
When the polymer according to an embodiment of the present invention is used as a dental adhesive composition, the structural unit (X) improves the adhesion with the filling material, and the structural unit (Z) improves the adhesion with the tooth structure. Improves adhesion. The structural unit (Y) improves the compatibility with the tooth substance and the filling material, and improves the permeability into the tooth surface and the compatibility with the filling material. As a result, the dental adhesive composition containing the polymer according to one embodiment of the present invention exhibits high adhesiveness to tooth surfaces and filling materials.

When curing a dental adhesive composition containing a polymer according to an embodiment of the present invention, the dental adhesive composition composed of monomer components is made to proceed with polymerization to a polymer that originally has a certain degree of polymerization. Compared to other compositions, it has fewer unbonded parts and can be easily cured with fewer radicals. Thereby, according to the polymer according to one embodiment of the present invention, a dental adhesive composition that can be cured using radicals generated when curing the filling material can be obtained. Therefore, it is possible to realize an adhesive that does not require curing before filling with the filler material, is easily cured, and is applicable to various filler materials regardless of the composition of the filler material.

In the above general formula (2), when R ³ is a hydrogen atom, R ⁴ is a group having a total carbon number of 1 to 15, and when R ³ is a methyl group, R ⁴ is a group having a total carbon number of 4 to 15. May represent a group.
This makes it easy to obtain a polymer with fluidity. As a result, when the dental adhesive composition containing the polymer according to an embodiment of the present invention is applied to the tooth surface as a dental adhesive, it easily adheres to the tooth surface and is also easily compatible with the filling material. This makes it possible to form an adhesive layer with higher adhesive strength.

The polymer may be a liquid adhesive polymer.
Thereby, an adhesive layer with higher adhesive strength can be formed.

The weight average molecular weight of the polymer measured by gel permeation chromatography (GPC) using styrene as a standard may be 1,000 or more and 50,000 or less.
As a result, a suitable viscosity is obtained, which improves the adhesion between the tooth surface and the filling material, and provides higher adhesive strength.

In the general formula (3), L may be a dihydrogen phosphate monoester group {-OP(=O)(OH) ₂ }.
This improves the adhesion to the tooth surface, and when used as a dental adhesive, it is possible to form an adhesive layer with higher adhesive strength.

The structural unit (Y) represented by the above general formula (2) is methyl acrylate, ethyl acrylate, propyl acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, (meth)hexyl, (meth) Heptyl acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, 2-methoxyethyl (meth)acrylate , 2-ethoxyethyl (meth)acrylate, and 2-(2-methoxyethoxy)ethyl (meth)acrylate.
Thereby, the structural unit (Y) can further improve the permeability to the tooth surface and the compatibility with the filling material, and good adhesion to the tooth surface and the filling material can be obtained. Therefore, when this polymer is used in a dental adhesive, an adhesive layer with higher adhesive strength can be formed.

A dental adhesive composition according to one embodiment of the present invention contains the above polymer, a polymerizable monomer, a solvent, and water.
As described above, this dental adhesive composition provides high adhesion to tooth surfaces and filling materials, and can form an adhesive layer with higher adhesive strength.

According to the present invention, there is provided a polymer that does not require light irradiation before filling with a filling material, is easily cured, and is applicable to various filling materials, and a dental adhesive composition containing the same. Can be done.

1 is a partial cross-sectional view schematically showing a process of bonding a filling material to a tooth using an adhesive composition according to an embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail. In addition, in the following explanation, the numerical range of "x to y" shall include x and y, that is, "x to y" shall mean "more than or equal to x and less than or equal to y." In this book, the term "(meth)acrylic" refers to both "acrylic" and "methacrylic." Similarly, the term "(meth)acrylate" refers to both "acrylate" and "methacrylate," and the term "(meth)acryloyl" refers to both "acryloyl" and "methacryloyl."

<Overall configuration>
The polymer of one embodiment of the present invention can be used to repair teeth damaged by caries or the like. More specifically, the polymer of one embodiment of the present invention is contained in a dental adhesive composition (hereinafter simply referred to as an adhesive composition) and used as a dental filling material (hereinafter simply referred to as an adhesive composition) to be filled into a damaged area of a tooth. (hereinafter simply referred to as a filling material) can be used to adhere to the tooth structure that constitutes the surface of the damaged area.

The polymer according to this embodiment includes structural units (X) to (Z) and has adhesive properties to tooth structure and filling material.

The adhesive composition containing the polymer according to the present embodiment is applied to the concave damaged part of the tooth and is filled with the filling material without curing the adhesive composition. FIG. 1 is a partial sectional view schematically showing a state in which a damaged part of a tooth is filled with a filling material via an adhesive composition. In the state shown in FIG. 1, the uncured adhesive composition and the uncured filler material are in direct contact.

When light irradiation is performed to cure the filling material from the state shown in FIG. 1, radicals are generated by the action of the photopolymerization initiator in the filling material, and photopolymerization type curing progresses.

General photo-curable dental adhesives contain adhesive components as monomers, and in order to obtain high adhesive strength, a sufficient amount of radicals is supplied to fully polymerize and harden the various monomers. There is a need. In such an adhesive, when polymerization is progressed using irradiation light that has passed through the filler material, residual monomer exists in the interior where light cannot easily reach, resulting in a decrease in adhesive strength.
On the other hand, when the above-mentioned polymer is used in an adhesive composition, the adhesive component has been polymerized in advance, so that even a small amount of radicals can sufficiently progress the polymerization and cure the adhesive composition. .

The adhesive composition containing the polymer according to the present embodiment utilizes radicals generated from the photopolymerization initiator that is always included in the photocurable filling material, so it is not a filling material with a special composition but a general one. It is widely applicable to light-curable filling materials. Further, the filling material to which the adhesive composition containing the polymer according to the present embodiment is applied is not particularly limited as long as it contains a compound that generates radicals, and a chemical polymerization type is also applicable.

Therefore, by using the polymer according to this embodiment, the adhesive composition can be cured quickly and sufficiently, so that an adhesive layer with high adhesive strength can be obtained while suppressing the burden on the patient.

<Detailed configuration>
[polymer]
(Structural unit (X))
The structural unit (X) is represented by the following general formula (1) and is a structural unit derived from a (meth)acrylic monomer having a radically polymerizable unsaturated group. The structural unit (X) is bonded to the filling material by radical polymerization, and provides good adhesion to the filling repair material.
(In general formula (1), R ¹ and R ² represent a hydrogen atom or a methyl group, and n represents an integer of 1 to 15.)

Structural unit (X) can be obtained by Synthesis Method I and Synthesis Method II described below. Synthesis method I is preferred in order to reliably obtain structural unit (X).

In Synthesis Method I, a base is applied to a polymer synthesized using (meth)acrylate represented by the following general formula (4) or (5) as one of the copolymerization components to extract protons and eliminate E. Separation to obtain structural unit (X).
(In general formulas (4) and (5), E represents an anionic leaving group, R ⁶ , R ⁷ , R ⁸ and R ⁹ represent a hydrogen atom or a methyl group, and p and q are 1 to 15 represents an integer.)

As the anionic leaving group, a halogen atom, an alkyl or arylsulfonyloxy group, etc. are preferred, and a bromine atom, a chlorine atom, and a p-toluenesulfonyloxy group are particularly preferred.
Specifically, due to the ease of obtaining synthetic raw materials, 2-((3-bromo-2-methylpropanoyl)oxy)ethyl methacrylate, 2-((3-bromo-2-methylpropanoyl)oxy)ethyl Acrylate, 2-((3-bromopropanoyl)oxy)ethyl methacrylate, 2-((3-chloro-2-methylpropanoyl)oxy)ethyl methacrylate, 2-((3-chloro-2-methylpropanoyl) Examples include oxy)ethyl acrylate, 2-((3-chloropropanoyl)oxy)ethyl methacrylate, and the like.

As the base that induces the elimination reaction, either an inorganic base or an organic base may be used.
Preferred inorganic compound bases include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium hydrogen carbonate, potassium carbonate, potassium hydrogen carbonate, etc., and organic compound bases include sodium methoxide, sodium ethoxide, potassium t- Examples include metal alkoxides such as butoxide, and organic amine compounds such as triethylamine, pyridine, and diisopropylethylamine.

In Synthesis Method II, a polymer synthesized using (meth)acrylate containing a hydroxyl group as one of the copolymerization components is reacted with (meth)acrylic acid chloride, (meth)acrylic anhydride, etc. to form the structural unit (X ).

(Structural unit (Y))
The structural unit (Y) is represented by the following general formula (2) and is a structural unit derived from a (meth)acrylic monomer having an alkyl group, and the alkyl group may include an ethylene glycol chain. Containing the structural unit (Y) can improve compatibility with the tooth surface and the filling material, improve permeability into the tooth surface and compatibility with the monomer of the filling material, and improve the compatibility with the tooth surface and the filling material. An adhesive layer with good adhesion is formed.
(In general formula (2), R ³ represents a hydrogen atom or a methyl group, and R ⁴ represents a group having a total carbon number of 1 to 15 represented by the following general formula (2-1).)
(In the above formula, p represents an integer from 0 to 5, and R' represents an alkyl group.)

From the viewpoint of further improving the permeability into the tooth surface and the compatibility with the monomer of the filling material, in general formula (2), when R ³ is a hydrogen atom, R ⁴ is a group having a total number of carbon atoms of 1 to 15. When R ³ is a methyl group, R ⁴ preferably represents a group having 4 to 15 carbon atoms in total. As a result, the polymer according to the present embodiment has good fluidity, which improves the adhesion to the tooth surface and the filling material.

In particular, from the viewpoint of making the polymer liquid-like, the structural unit (Y) represented by general formula (2) is methyl acrylate, ethyl acrylate, propyl acrylate, (meth)butyl acrylate, (meth) Pentyl acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, (meth) A structure derived from a monomer selected from dodecyl acrylate, 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, and 2-(2-methoxyethoxy)ethyl (meth)acrylate. It is preferable that there be.

(Structural unit (Z))
The structural unit (Z) is represented by the following general formula (3) and has a structure derived from a (meth)acrylic monomer containing an acidic group. The acidic group (L) of the structural unit (Z) has a demineralizing effect on the tooth substance, and also serves as an adhesive component to the tooth substance, thereby improving the adhesion of the filling and restorative material to the tooth substance.
(In general formula (3), R ⁵ represents a hydrogen atom or a methyl group, and L represents a dihydrogen phosphate monoester group {-O-P(=O)(OH) ₂ } or a phosphono group {-P( =O)(OH) ₂ }, m represents an integer from 1 to 15.)

L is a dihydrogen phosphate monoester group {-O-P(=O)(OH) ₂ } because it has high stability against water and can slowly dissolve the smear layer on the tooth surface and demineralize the tooth. It is preferable.

Specifically, the structural unit (Z) having a dihydrogen phosphate monoester group includes 2-(phosphonooxy)ethyl methacrylate, 6-(phosphonooxy)hexyl(meth)acrylate, 10-(phosphonooxy)decyl(meth) Examples include acrylate.

Specific examples of the structural unit (Z) having a phosphono group include 3-(meth)acryloyloxypropylphosphonic acid, 6-(meth)acryloylhexylphosphonic acid, 10-(meth)acryloyloxydecylphosphonic acid, etc. Can be mentioned.

(Ratio of each structural unit (X), (Y), (Z))
The polymer of one embodiment of the present invention has 5 to 80 mol% of the structural unit (X), 15 to 90 mol% of the structural unit (Y), and 5 to 50 mol% of the structural unit (Z), and more preferably , (X) 10 to 70 mol%, structural unit (Y) 20 to 80 mol%, and structural unit (Z) 10 to 40 mol%. As a result, the above-mentioned functions of each structural unit can be exhibited without deterioration, and an adhesive layer having high adhesive strength can be obtained due to the synergistic effect of the structural units (X) to (Z).

(Polymer properties)
The polymer of one embodiment of the invention is typically a liquid adhesive polymer. Liquid state means a property that has fluidity at room temperature (15 to 30°C). That is, the polymer according to the present embodiment is typically not solid but has the property of flowing and moving in an amorphous manner. As a result, the permeability into the tooth surface and the compatibility with the monomer of the filling material are further improved, and the adhesion to the tooth surface and the filling material is improved.

(polymer molecular weight)
Weight average molecular weight is determined by gel permeation chromatography (GPC) using styrene as a standard. By having a weight average molecular weight of 1,000 or more and 50,000 or less, it has a suitable viscosity, so when applied to the tooth surface as a dental adhesive material, the applied film does not run and can maintain the desired thickness. Even if air blowing is performed to remove the solvent later, the film remains uniform. Thereby, an adhesive layer with high adhesive strength can be formed.
From the viewpoint of obtaining even higher adhesive strength, the weight average molecular weight of the polymer is more preferably greater than 2,000, and even more preferably less than 20,000.

[Dental adhesive composition]
The dental adhesive composition of one embodiment of the present invention contains the above polymer, a polymerizable monomer, a solvent, and water, and is configured as a so-called one-component composition. The dental adhesive composition of one embodiment of the present invention is configured to utilize the action of the photopolymerization initiator contained in the filling material, and therefore does not contain a photopolymerization initiator. Therefore, the dental adhesive composition of one embodiment of the present invention can be applied as a one-component dental adhesive that does not require light irradiation.

(Polymerizable monomer)
As the polymerizable monomer, any known polymerizable monomer can be used without restriction, but from the viewpoint of obtaining even higher adhesiveness and adhesive durability to tooth material, acidic group It is preferable that the polymerizable monomer further contains an acidic group-free polymerizable monomer.

As the acidic group-free polymerizable monomer, any known compound can be used without particular restriction as long as it does not contain an acidic group and contains one or more polymerizable unsaturated groups in one molecule. . From the viewpoint of adhesion, the polymerizable unsaturated group is preferably an acryloyl group, a methacryloyl group, an acrylamide group, a methacrylamide group, or the like.

Among the non-acidic group-containing polymerizable monomers, polyfunctional polymerizable monomers are preferably used from the viewpoint of adhesion to tooth substance and adhesive durability. Specific examples of preferably used polyfunctional polymerizable monomers include 2,2'-bis{4-[2-hydroxy-3-(meth)acryloyloxypropoxy]phenyl}propane, triethylene glycol Methacrylate, 2,2-bis[(4-(meth)acryloyloxypolyethoxyphenyl)propane], 1,6-bis(methacrylethyloxycarbonylamino)-2,2,4-trimethylhexane, 1,6-bis Examples include (methacrylethyloxycarbonylamino)-2,4,4-trimethylhexane and trimethylolpropane trimethacrylate.

Only one type of acidic group-free polymerizable monomer may be used, or two or more types may be used in combination. The acidic group-free polymerizable monomers may be used alone or in combination of two or more.

The blending ratio of the acidic group-free polymerizable monomer is not particularly limited, but from the viewpoint of further securing the adhesion improvement effect of the polymer, the blending ratio of the acidic group-free polymerizable monomer is The amount is preferably from 10 parts by weight to 10,000 parts by weight, more preferably from 20 parts by weight to 5,000 parts by weight, based on 100 parts by weight of the polymer.

(water)
The water is preferably substantially free of harmful impurities from the viewpoints of storage stability, biocompatibility, and adhesiveness, and examples of water that can be used include deionized water, distilled water, and the like. The mixing ratio of water is 10 parts by mass to 1000 parts by mass, preferably 20 parts by mass to 500 parts by mass, and particularly preferably 50 parts by mass to 200 parts by mass, based on 100 parts by mass of the polymer.

(organic solvent)
As the organic solvent, any known organic solvent can be used without limitation, but it is usually preferable to use a highly volatile organic solvent with a boiling point of less than 100°C. The blending ratio of the organic solvent is 10 parts by mass to 3000 parts by mass, preferably 30 parts by mass to 1000 parts by mass, based on 100 parts by mass of the polymer.

Specifically, examples of the organic solvent include alcohols such as ethanol, isopropyl alcohol, and butanol; and ketones such as acetone and methyl ethyl ketone. Among these, acetone, ethanol, isopropyl alcohol, etc. are particularly preferably used for reasons such as biosafety, solubility, and storage stability. As the organic solvent, one kind or a combination of two or more kinds of organic solvents can be used.

(Other ingredients)
The adhesive composition may contain components other than the above-mentioned components, such as various additives, as necessary. Examples of additives include polyvalent metal compounds, fillers, colorants, and polymerization inhibitors such as hydroquinone, hydroquinone monomethyl ether, and dibutylhydroxytoluene.

Incidentally, since the polymer of the present invention has a novel structure, it may be useful for a wide range of uses other than adhesives. In other words, the use of the polymer of the present invention is not limited to adhesives.

The present invention will be described below with reference to Examples, but the present invention is not limited to the following Examples.

<Abbreviation of substance>
First, the abbreviations of substances used in Examples and Comparative Examples will be explained below.
[Monomer of structural unit (X)]
BrMPMA: 2-((3-bromo-2-methylpropanoyl)oxy)ethyl methacrylate BrMPA: 2-((3-bromo-2-methylpropanoyl)oxy)ethyl acrylate BrPMA: 2-((3-bromo-2-methylpropanoyl)oxy)ethyl acrylate Noyl)oxy)ethyl methacrylate [monomer of structural unit (Y)]
MA: Methyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.)
DGMA: Diethylene glycol monomethyl ether methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.)
BMA: Butyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.)
MMA: Methyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.)
DMA: Dodecyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.)
TDMA: Tridecyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.)
[Monomer of structural unit (Z)]
PM1: 2-(phosphonooxy)ethyl methacrylate (P-1M (manufactured by Kyoeisha Chemical Co., Ltd.) purified with water/dichloromethane)
PA1: 2-(phosphonooxy)ethyl acrylate (P-1A (manufactured by Kyoeisha Chemical Co., Ltd.) purified with water/dichloromethane)
MDP: 10-(phosphonooxy)decyl methacrylate (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.)
[Other monomers]
Bis-GMA: 2,2'-bis[4-(3-methacryloyloxy)-2-hydroxypropoxyphenyl]propane (manufactured by Shin Nakamura Chemical Co., Ltd.)
3G: Triethylene glycol dimethacrylate (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.)
HEMA: 2-hydroxyethyl methacrylate (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.)
AA: Acrylic acid (manufactured by Tokyo Chemical Industry Co., Ltd.)
ODMA: Octadecyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.)
[Other compounds]
THF: Tetrahydrofuran (manufactured by Fujifilm Wako Pure Chemical Industries)
TEA: Triethylamine (manufactured by Fujifilm Wako Pure Chemical Industries)
DIPE: Diisopropyl ether (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)
AIBN: Azobis (isobutyronitrile) (manufactured by Fujifilm Wako Pure Chemical Industries)

<Examples 1 to 16, Comparative Examples 1 to 5>
[Polymer synthesis]
Polymers [1] to [21] according to Examples 1 to 16 and Comparative Examples 1 to 5 were synthesized by the following method. The components and blending ratios of each polymer are as shown in Table 1 below.

First, a monomer of the structural unit (X) was synthesized.
1.7 g (15 mmol) of 3-bromoisobutyric acid (manufactured by Tokyo Chemical Industry Co., Ltd.) was weighed into a 200 mL round-bottom flask. Furthermore, 100 mL of THF was added, followed by 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide (manufactured by Tokyo Kasei Kogyo Co., Ltd.); 3.5 g (18 mmol), 4-dimethylaminopyridine (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.); ); 0.1 g (1 mmol) and 2-hydroxyethyl acrylate (manufactured by Shin-Nakamura Chemical Industries, Ltd.); 1.3 g (10 mmol) were added. After 6 hours, the solvent was removed using an evaporator, and ethyl acetate (100 mL) was added. The ethyl acetate layer was washed three times with water (100 mL). Magnesium sulfate was added to the ethyl acetate layer to dry it, and ethyl acetate was distilled off under reduced pressure using an evaporator. The obtained compound was dried at 80° C. for 1 hour while bubbling oxygen to obtain 2.2 g of BrMPMA in a yield of 75%.
In addition, when synthesizing BrMPA, 2-hydroxyethyl acrylate (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was used instead of 2-hydroxyethyl methacrylate, and when synthesizing BrPMA, 3-bromobutyric acid (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was used. was used.

Next, a polymer was synthesized by the following method.
(1) Polymer [1] according to Example 1 was synthesized by synthesis method (i).
First, as shown in the reaction formula below, a polymerizable group precursor polymer [1] was synthesized.
133 mg (0.5 mmol) of BrMPA, 98 mg (0.5 mmol) of PA1, and 164 mg (1 mmol) of AIBN were weighed into a 100 mL round-bottom flask. After nitrogen substitution, 20 mL of THF/water (8/2) mixed solvent was added, and then 806 μl (9 mmol) of MA was added to the system. The mixture was heated and stirred at 65° C. for 24 hours using an oil bath. Disappearance of the monomer was confirmed by HPLC, and THF was distilled off under reduced pressure using an evaporator. The obtained crude product was reprecipitated using 20 mL of DIPE/THF (9/1) mixed solvent under an ethanol/dry ice bath, and then vacuum-dried to obtain the polymerizable group precursor polymer [1]. Obtained.

Next, polymer [1] was synthesized.
Polymerizable group precursor polymer [1] was dissolved in 20 mL of dichloromethane, and 2 mL of TEA was added. After stirring at room temperature for 6 hours, 20 mL of 1N hydrochloric acid was added to perform a washing operation. The dichloromethane layer was further washed twice with 20 mL of 1N hydrochloric acid. The dichloromethane layer was dried over magnesium sulfate, dichloromethane was distilled off under reduced pressure using an evaporator, and 790 mg (yield: 82%) of polymer [1] was obtained. According to ¹ H-NMR measurement, the composition ratio is structural unit (X) (mol%): structural unit (Y) (mol%): structural unit (Z) (mol%) = 5:90:5 (=x:y: z), and the weight average molecular weight Mw was 1100 as determined by GPC measurement.

(2) Polymer [2] according to Example 2 was synthesized by synthesis method (ii).
First, as shown in the reaction formula below, a polymerizable group precursor polymer [2] was synthesized.
164 mg (1 mmol) of AIBN was weighed into a 100 mL square flask. After nitrogen substitution, 15 mL of THF/water (8/2) mixed solvent was added, and then 717 μl (8 mmol) of MA was added to the system. Subsequently, the reaction system was heated to 65°C using an oil bath. A solution of 210 mg (1 mmol) of PM1 and 278 mg (1 mmol) of BrMPMA in 5 mL of a THF/water (8/2) mixed solvent was added dropwise over 3 hours using a syringe pump. After the dropwise addition was completed, the reaction was further carried out at 65° C. for 21 hours, the disappearance of the monomer was confirmed by HPLC, and THF was distilled off under reduced pressure using an evaporator. The obtained crude product was reprecipitated using 20 mL of diisopropyl ether/THF (8/2) under an ethanol/dry ice bath, and then vacuum dried to obtain a polymerizable group precursor polymer [2]. Ta.

Next, polymer [2] was synthesized.
The polymerizable group precursor polymer [2] was converted to polymer [2] in the same manner as synthesis method (i), and 942 mg (yield 86%) of polymer [2] was obtained. According to ¹ H-NMR measurement, the composition ratio is structural unit (X) (mol%): structural unit (Y) (mol%): structural unit (Z) (mol%) = 9:81:10 (=x:y: z), and the weight average molecular weight Mw was 3300 as determined by GPC measurement.

(3) Polymers [3] to [11] and [14] to [20] according to Examples 3 to 11, 14 to 16 and Comparative Examples 1 to 4 were synthesized. Polymers [3] to [11] and [14] to [20] were synthesized using a method similar to synthesis method (i) or (ii). Due to the difference in copolymerizability between methacrylate monomers and acrylate monomers, synthesis method (i) is used when only methacrylate monomers or acrylate monomers are used, and synthesis method (ii) is used when methacrylate monomers and acrylate monomers are used together. there was.

(4) Polymers [12], [13], and [21] according to Examples 12 and 13 and Comparative Example 5 were synthesized as shown in the reaction formula below. The same method as synthesis method (i) was used except that 82 mg (0.5 mmol) of AIBN was used.

[Polymer analysis]
Table 1 shows the properties, weight average molecular weight, and yield of the obtained polymer. Since the polymer of this embodiment converts a polymerizable group precursor into a polymerizable group, there is no protection/deprotection step and the number of steps is small. Therefore, there was little loss due to purification, and yields were high in all cases.
The weight average molecular weight was measured by the following method.

1H-NMR measurement: JNM-ECA II (400 MHz) manufactured by JEOL Ltd. was used as a measuring device. Using deuterated chloroform as a measurement solvent, the measurement sample was diluted 100 times and measured.
GPC measurement: Advanced Polymer Chromatography manufactured by Nippon Waters was used as a measuring device. Furthermore, ACQUITY APCTMXT45 (1.7 μm) and ACQUITY APCTMXT125 (2.5 μm) were used as columns, and the column temperature was 40°C. THF was used as the developing solvent, and the flow rate was 0.5 ml/min. A 210 nm photodiode array detector was used as a detector. Furthermore, the measurement sample was diluted 100 times using THF as a measurement solvent.

<Examples 17 to 32 and Comparative Examples 6 to 11>
Adhesive compositions of Examples 17 to 32 and Comparative Examples 6 to 12 were prepared and evaluated for adhesive strength.

[Synthesis of dental adhesive composition]
Adhesive compositions according to Examples 17 to 32 and Comparative Examples 6 to 11 were prepared with the following compositions. Note that the numbers in parentheses represent parts by weight.
Composition: Polymer (10)/Bis-GMA (6)/3G (4)/Acetone (60)/Water (20)
Bis-GMA and 3G were used as polymerizable monomers.

A dental adhesive composition according to Comparative Example 12 was prepared with the following composition. In Comparative Example 12, no polymer was used. Note that the numbers in parentheses represent parts by weight.
Composition: MDP (4) / HEMA (6) / Bis-GMA (6) / 3G (4) / Acetone (60) / Water (20)
MDP, HEMA, Bis-GMA and 3G were used as polymerizable monomers.

[Evaluation of adhesive composition]
Next, the "tensile adhesive strength" of the adhesive composition containing the obtained polymer was evaluated.

Adhesive strength to tooth substance was measured as follows.
A bovine front tooth extracted within 24 hours after slaughter was polished with water-resistant abrasive paper P600 under water injection, and an adherend was prepared by carving out the dentin or enamel plane so that it was parallel and flat to the labial surface. .
Next, double-sided tape with holes of 3 mm in diameter was attached to the polished surfaces of each of these two types of adherends. Subsequently, the dental adhesive compositions prepared in each Example and each Comparative Example were applied to the adhesive surface of the polished surface exposed through the holes of the double-sided tape, and dried by air blowing for 5 seconds.
A piece of paraffin wax with a thickness of 0.5 mm with a hole of 8 mm in diameter was pasted on the adhesive surface coated with the dental adhesive composition so that the hole in the paraffin wax and the hole in the double-sided tape were concentric. A mock cavity was created. This simulated cavity was filled with dental composite resin (Estelite Universal Flow, manufactured by Tokuyama Dental Co., Ltd.) and lightly pressed with a polyester film, and then exposed to light for 10 seconds using a visible light irradiator (Eliper, manufactured by 3M ESPE). Photocuring was performed using Thereafter, a pre-polished SUS304 round bar (diameter 8 mm, height 18 mm) was bonded with resin cement (Estecem II, manufactured by Tokuyama Dental Co., Ltd.) to prepare a sample for evaluation. The composite resin used is a photopolymerizable composition containing camphorquinone and an amine compound. After this test sample was immersed in water at 37°C for 24 hours, a load was started using a universal testing machine (Model AG-I, manufactured by Shimadzu Corporation) at a crosshead speed of 1 mm/mm, and the measurement sample was A load was applied to the test sample until it broke, and the adhesive strength was determined from the maximum load using the following formula.
Adhesive strength (MPa) = maximum load (N)/adhered area (mm ² ).

In the adhesive compositions according to Examples 17 to 32, good tensile adhesive strength was obtained in all Examples.

The adhesive compositions according to Comparative Examples 6 to 11 are examples in which each component uses a polymer that does not satisfy the configuration shown in the present invention. Comparative Example 6 was an example without the structural unit (Z) and exhibited low adhesive strength. Moreover, Comparative Example 7 was an example without the structural unit (X) and exhibited low adhesive strength. Comparative Examples 8 to 10 have structures in which R ⁴ is an ethanol group (CH ₂ CH ₂ OH) or the total number of carbon atoms in R ⁴ is 0 or 18 (that is, R ⁴ is H, C ₁₈ H ₃₅ ). This is an example without the unit (Y) and exhibited low adhesive strength. Comparative Example 11 is an example in which the polymer of the present invention was not used and exhibited low adhesive strength.

Claims (7)

5 to 80 mol% of the structural unit (X) represented by the following general formula (1), 15 to 90 mol% of the structural unit (Y) represented by the following general formula (2), and the following general formula (3) A polymer having a structural unit (Z) of 5 to 50 mol%.
(In general formula (1), R ¹ and R ² represent a hydrogen atom or a methyl group, and n represents an integer of 1 to 15.)
(In general formula (2), R ³ represents a hydrogen atom or a methyl group, and R ⁴ represents a group having a total carbon number of 1 to 15 represented by the following general formula (2-1).)
(In the above formula, p represents an integer from 0 to 5, and R' represents an alkyl group.)
(In general formula (3), R ⁵ represents a hydrogen atom or a methyl group, and L represents a dihydrogen phosphate monoester group {-O-P(=O)(OH) ₂ } or a phosphono group {-P( =O)(OH) ₂ }, m represents an integer from 1 to 15.) The polymer according to claim 1,
In general formula (2), when R ³ is a hydrogen atom, R ⁴ is a group having a total number of carbon atoms of 1 to 15; when R ³ is a methyl group, R ⁴ is a group having a total number of carbon atoms of 4 to 15. represents,
polymer. The polymer according to claim 1 or 2,
the polymer is a liquid adhesive polymer;
polymer. The polymer according to any one of claims 1 to 3,
The polymer has a weight average molecular weight of 1,000 or more and 50,000 or less as measured by gel permeation chromatography (GPC) using styrene as a standard. A polymer according to any one of claims 1 to 4,
A polymer in which, in the general formula (3), L is a dihydrogen phosphate monoester group {-OP(=O)(OH) ₂ }. The polymer according to any one of claims 1 to 5,
The structural unit represented by the general formula (2) is methyl acrylate, ethyl acrylate, propyl acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, (meth)hexyl, or (meth)acrylic acid. Butyl, octyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, (meth)acrylate ) A polymer having a structure derived from a monomer selected from 2-ethoxyethyl acrylate and 2-(2-methoxyethoxy)ethyl (meth)acrylate. A dental adhesive composition comprising the polymer according to any one of claims 1 to 6, a polymerizable monomer, a solvent, and water.

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