JP6905667B2 - Method for Producing Fumaric Acid Ester Homopolymer - Google Patents

Description

The present invention relates to a method for producing a fumaric acid ester homopolymer by photopolymerization.

Photopolymerizable compositions that polymerize by irradiating with energy rays such as ultraviolet rays are widely used in various applications. The photopolymerizable composition includes a radical polymerization type and a cationic polymerization type. As the radical polymerization type, a compound having an (meth) acryloyl group and a compound having an unsaturated double bond such as an unsaturated polyester compound are known, and as a cationic polymerization type, a compound having an epoxy group and a vinyl ether group are known. Compounds and the like having the above are known. In general, the radical polymerization type has a feature that the polymerization rate is high and the hardness of the coating film formed is high, but it has a drawback that the adhesion to the substrate is weak. In addition, it is easily affected by oxygen, and equipment such as nitrogen filling is required especially for the formation of thin films. Further, a compound having a (meth) acryloyl group has a high viscosity and is therefore difficult to handle.

On the other hand, fumaric acid dialkyl ester compounds are known to undergo radical polymerization like compounds having a (meth) acryloyl group, have a high glass transition temperature, have excellent heat resistance, and are colorless and transparent. The fumaric acid dialkyl ester polymer is synthesized (Patent Document 1). However, the fumaric acid dialkyl ester compound is difficult to homopolymerize, and a method of copolymerizing with another polymerizable compound is common. Further, a method for homopolymerizing a fumaric acid dialkyl ester compound has also been developed in recent years (Patent Documents 2, 3 and 4). However, Patent Document 1 describes an example of producing a fumaric acid dialkyl ester polymer by photopolymerization, but does not describe an example of homopolymerizing a fumaric acid dialkyl ester polymer. Further, Patent Documents 2 and 3 describe an example in which a fumaric acid dialkyl ester compound is homopolymerized, but this is a method by thermal polymerization, and no method by photopolymerization is described. Further, Patent Document 4 describes an example in which fumaric acid diester is homopolymerized by photopolymerization, but the ester moiety of fumaric acid diester has an extremely complicated structure, and an alkyl chain having a simple structure is used. No description is given about homopolymerization of the fumaric acid alkyl ester compound at the ester moiety by photopolymerization. In general, fumaric acid diester can easily carry out radical polymerization by introducing a substituent having a large steric hindrance into the ester moiety, but fumaric acid diester has an alkyl chain having a small steric hindrance and a simple structure at the ester moiety. Photopolymerization of acid alkyl ester compounds is known to be difficult.

On the other hand, in recent years, the development of UV-LED has been remarkable, and UV-LEDs in various wavelength ranges such as 365 nmUV-LED, 385 nmUV-LED, 395 nmUV-LED, and 405 nmUV-LED have appeared on the market, and are more efficient than thermal polymerization. It is attracting attention as a method for obtaining polymers.

Japanese Unexamined Patent Publication No. 2000-143741 Japanese Unexamined Patent Publication No. 2009-108194 Japanese Unexamined Patent Publication No. 2011-021102 Japanese Unexamined Patent Publication No. 2003-231666

An object of the present invention is to provide a method for producing a fumaric acid ester homopolymer by homopolymerizing a fumaric acid ester compound having an alkyl chain having a simple structure at an ester moiety by photopolymerization.

As a result of diligent studies on the structure of the fumaric acid ester compound and the specification of photopolymerization, the present inventor photopolymerizes even a fumaric acid ester compound having an alkyl chain having a simple ester site structure using a light source in a specific wavelength range. As a result, it was found that a fumaric acid ester homopolymer can be easily obtained, and the present invention has been completed.

That is, the first gist of the present invention is to use a photopolymerizable composition containing at least the fumaric acid ester compound represented by the general formula (1) and a photopolymerization initiator as a light source and have a wavelength range of 365 nm to 405 nm. A method for producing a fumaric acid ester homopolymer, which comprises photopolymerizing by irradiating with light.

(In the above general formula (1), R ¹ and R ² represent either a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. However, ^{both R 1} and R ² do not become hydrogen atoms. )

A second gist of the present invention lies in the method for producing a fumaric acid ester homopolymer described in the first gist, wherein the light source for irradiating energy rays is a UV-LED.

A third gist of the present invention resides in the method for producing a fumaric acid ester homopolymer according to the second gist, wherein the UV-LED is either a 385 nm UV-LED, a 395 nm UV-LED or a 405 nm UV-LED.

In the present invention, by irradiating light having a wavelength range of 365 nm to 405 nm, a fumaric acid ester compound having an alkyl chain having a simple ester moiety structure can be homopolymerized, and a fumaric acid ester homopolymer can be efficiently produced. You can get it.

Hereinafter, the present invention will be described in detail.

(Photopolymerizable composition)
The present invention uses a photopolymerizable composition containing at least a fumaric acid ester compound represented by the general formula (1) and a photopolymerization initiator.

(In the above general formula (1), R ¹ and R ² represent either a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. However, ^{both R 1} and R ² do not become hydrogen atoms. )

Alkyl groups having 1 to 20 carbon atoms represented by R ¹ and R ² include methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group and t-butyl group. n-amyl group, i-amyl group, n-hexyl group, n-heptyl group, n-octyl group, 2-ethylhexyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, Linear and branched n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group, n-nonadecil group, n-icosyl group, cyclohexyl group, etc. Chain or cyclic alkyl groups can be mentioned. Among these, from the viewpoint of heat resistance of the fumaric acid ester homopolymer, an i-propyl group, a t-butyl group and the like are preferable, and an i-propyl group is particularly preferable.

Examples of the fumaric acid ester compound represented by the specific general formula (1) include monomethyl fumarate, monoethyl fumarate, mono-n-propyl fumarate, dimono-i-propyl fumarate, and mono fumarate. -N-Butyl, mono-i-butyl fumarate, mono-t-butyl fumarate, mono-n-amyl fumarate, mono-i-amyl fumarate, mono-n-hexyl fumarate, mono-n fumarate -Heptyl, mono-n-octyl fumarate, mono-2-ethylhexyl fumarate, mono-n-nonyl fumarate, mono-n-decyl fumarate, mono-n-undecyl fumarate, mono-n-dodecyl fumarate , Mono-n-tridecyl fumarate, mono-n-tetradecyl fumarate, mono-n-pentadecyl fumarate, mono-n-hexadecyl fumarate, mono-n-heptadecyl fumarate, mono-n-octadecyl fumarate, fumal Examples thereof include fumaric acid monoester compounds such as acid mono-n-nonadecil, fumaric acid mono-n-icosyl, and fumaric acid monocyclohexyl. In addition, dimethyl fumarate, diethyl fumarate, di-n-propyl fumarate, di-i-propyl fumarate, di-n-butyl fumarate, di-i-butyl fumarate, di-t-butyl fumarate, Di-n-amyl fumarate, di-i-amyl fumarate, di-n-hexyl fumarate, di-n-heptyl fumarate, di-n-octyl fumarate, bis (2-ethylhexyl) fumarate, fumal Di-n-nonyl acid, di-n-decyl fumarate, di-n-undecyl fumarate, di-n-dodecyl fumarate, di-n-tridecyl fumarate, di-n-tetradecyl fumarate, di-fumarate -N-pentadecyl, di-n-hexadecyl fumarate, di-n-heptadecyl fumarate, di-n-octadecyl fumarate, di-n-nonadecil fumarate, di-n-icosyl fumarate, dicyclohexyl fumarate, fumar Ethyl-methyl fumarate, ethyl-n-propyl fumarate, ethyl-i-propyl fumarate, ethyl-n-butyl fumarate, ethyl-i-butyl fumarate, ethyl-t-butyl fumarate, ethyl fumarate-n -Amil, ethyl-i-amyl fumarate, ethyl-n-hexyl fumarate, ethyl-n-heptyl fumarate, ethyl-n-octyl fumarate, ethyl fumarate- (2-ethylhexyl), ethyl fumarate-n -Nonyl, ethyl-n-decyl fumarate, ethyl-n-undecyl fumarate, ethyl-n-dodecyl fumarate, ethyl-n-tridecyl fumarate, ethyl-n-tetradecyl fumarate, ethyl-n-pentadecyl fumarate , Fumaric acid such as ethyl-n-hexadecyl fumarate, ethyl-n-heptadecyl fumarate, ethyl-n-octadecyl fumarate, ethyl-n-nonadecil fumarate, ethyl-n-icosyl fumarate, ethyl-cyclohexyl fumarate, etc. Diester compounds can be mentioned. Among these, di-t-butyl fumarate, bis (2-ethylhexyl) fumarate, ethyl-t-butyl fumarate, di-i-butyl fumarate, di-i-propyl fumarate, di-t fumarate -Butyl and the like are preferable, and bis (2-ethylhexyl) fumarate, di-t-butyl fumarate and di-i-propyl fumarate are particularly preferable.

The present invention is characterized in that it can be photopolymerized using a fumaric acid ester compound having a simple alkyl chain structure at the ester site.

In the present invention, as the polymerization initiator used when the fumaric acid ester compound represented by the general formula (1) is photopolymerized, a hydrogen abstraction type photopolymerization initiator can be used or irradiated with light. As a result, an intramolecular cleavage type photopolymerization initiator that decomposes the compound to generate radicals can also be used.

Examples of such an intramolecular cleavage type photopolymerization initiator include 2,2-dimethoxy-1,2-diphenylethane-1-one (trade name "Irgacure 651", manufactured by BASF Co., Ltd.). , Irgacure is a registered trademark of BASF Co., Ltd.), benzylmethyl ketals, 1-hydroxycyclohexylphenylketone (trade name "Irgacure 184", manufactured by BASF Co., Ltd.), 2-hydroxy -2-Methyl-1-phenylpropan-1-one (trade name "DaroCure 1173", manufactured by BASF, DaroCure is a registered trademark of BASF), 1- [4 -(2-Hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propane-1-one (trade name "Irgacure 2959", manufactured by BAS), 2-hydroxy-1 -{4- [4- (2-Hydroxy-2-methylpropionyl) -benzyl] phenyl} -2-methyl-1-one (trade name "Irgacure 127", manufactured by BAS), etc. α-Hydroxyalkylphenones, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one (trade name "Irgacure 907", manufactured by BAS), Α-Aminoacetophenones such as 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 (trade name "Irgacure 369", manufactured by BAS), acetophenone, Acetphenones such as 2-hydroxy-2-phenylacetophenone, 2-ethoxy-2-phenylacetophenone, 2-methoxy-2-phenylacetophenone, 2-isopropoxy-2-phenylacetophenone, 2-isobutoxy-2-phenylacetophenone, Benzyls, benzyls such as 4,4'-dimethoxybenzyl, anthraquinones such as 2-ethylanthraquinone, 2-t-butyl anthraquinone, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,4 Phosphine oxides such as 6-trimethylbenzoyldiphenylphosphine oxide (trade name "Irgacure TPO", manufactured by BASF), 1,2-octanedione 1- [4- (phenylthio) -2- (o) -Benzoyl oxime)] and 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl] -1- (o-) In addition to (keto) oxime esters such as acetyloxime), titanocene, benzophenones, imidazole derivatives, bisimidazole derivatives, N-arylglycine derivatives, organic azide compounds, aluminate complexes, organic peroxides, N-alkoxy Examples thereof include pyridinium salts and thioxanthone derivatives. Of course, the present invention is not limited to these examples as long as it does not go beyond the gist of the present invention. These may be used alone or in combination of two or more.

When a photopolymerization initiator is used, the amount used is usually 0.001% by weight or more and 20% by weight or less with respect to the fumaric acid ester compound represented by the general formula (1) in the photopolymerizable composition of the present invention. It can be used in the range of 0.01% by weight or more and 10% by weight or less. Further, these may be used alone or in combination of two or more.

(Other ingredients)
In addition, a solvent can be added to the photopolymerizable composition of the present invention, if necessary. The solvent used is not particularly limited, but is limited to hydrocarbon compounds such as hexane, heptane, cyclohexane and decalin, halogen-substituted hydrocarbons such as chloroform, carbon tetrachloride and dichloromethane, aromatic compounds such as benzene, toluene and xylene, and chlorobenzene. Halogen-substituted aromatics such as diethyl ether, tetrahydrofuran, tetrahydropyran, dioxane, propylene glycol monomethoxyacetate, ether compounds such as jiglime, ketone compounds such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, N-methylpyrrolidone and the like. Nitrogen atom-containing compounds, ester compounds such as ethyl acetate and butyl acetate are preferably used.

(Polymerization and curing of photopolymerizable composition)
The photopolymerizable composition of the present invention can be easily polymerized and cured by irradiating with light. Further, the photopolymerizable composition according to the present invention can be polymerized and cured by various methods. For example, a coating film, a film, or a sheet can be obtained by irradiating light on a material coated on an appropriate base material or a material in which the photopolymerizable composition is sandwiched between glass plates or the like having spacers arranged therein. .. In addition, a polymerized and cured molded product can be obtained by irradiating a mold in which the photopolymerizable composition is poured with light so as to transmit light. Further, by applying the photopolymerizable composition and then irradiating light through a mask having an appropriate pattern, polymerization and curing according to the pattern can be performed. Further, by irradiating the photopolymerizable composition discharged from the nozzle of the inkjet printer with light, the composition applied on the substrate is polymerized and cured, or the composition is polymerized to form a three-dimensional object. You can also do it.

Further, the photopolymerizable compound can be photopolymerized in the reactor by charging the photopolymerizable composition into an appropriate reactor such as a flask and irradiating with light while stirring if necessary. The polymerization by irradiation with light may be carried out in an inert atmosphere or in a normal atmosphere. For example, when the photopolymerizable composition of the present invention contains a radically polymerizable compound, by photopolymerizing in an inert atmosphere, the generated radicals are less likely to be consumed by oxygen, and the polymerization may proceed efficiently. ..

(light source)
As the light source used for irradiating the energy rays in the present invention, it is preferable to use a light source containing light having a wavelength of 300 to 500 nm. A light source containing a plurality of wavelength components may be used, or a light source that uses an LED or a laser beam and emits so-called monochromatic light may be used. Specifically, high-pressure mercury lamps, ultra-high-pressure mercury metal halide lamps, gallium-doped lamps, microwave-excited UV lamps (for example, H-valve, D-valve, V-valve manufactured by Fusion Co., Ltd.), 365 nm, 375 nm, 385 nm, Examples thereof include an LED lamp or laser light that emits light having a wavelength of 395 nm, 405 nm, 436 nm, or the like. It is also possible to use the light of lighting equipment such as sunlight, incandescent lamps, and fluorescent lamps. In particular, an LED lamp that emits light having a wavelength of 365 nm, 375 nm, 385 nm, 395 nm, 405 nm, 436 nm, or the like is preferable.

(Use of photopolymerizable composition)
The photopolymerizable composition according to the present invention can be used for coating agents, paints, inks, molding materials and the like that can be reacted, polymerized and cured by irradiation with energy rays. Specifically, coating agents and protective film materials such as paints, hard coating agents, antifouling films, antireflection films, shock absorbing films, and overcoating agents to be applied on substrates such as metals, resins, glass, paper, and wood. , Photo-curable adhesives, adhesives, photo-collapse / decomposition type paints, coatings, molded products, optical recording media such as hologram materials, materials for optical recording media, resins for optical modeling, inks for 3D printers (Resin), resists for manufacturing electronic circuits and semiconductors, resists for color filters for displays such as liquid crystal displays and organic EL displays, resists for black matrices, resists for electronic materials such as dry film resists, interlayer insulating films, protective films, optics. Extraction film, sealant, sealing material, printing ink for screen printing, offset printing, gravure printing, etc., photocurable ink for inkjet printers, laser patterning composition, lens, lens array, optical waveguide, light guide plate, It can be applied to various applications such as a light diffusing plate, a diffractive element, an optical member such as an optical adhesive, and a material for nanoprinting. Since the photopolymerizable sensitizer composition and the photopolymerizable composition of the present invention can suppress the coloring of the polymer and the cured product, in particular, video-related devices such as LCDs and organic EL displays, touch panels, lenses and the like It is suitably used for adhesives, adhesives, coating agents and the like such as OCA (Optical Clear Polymer) and OCR (Optical Clear Resin) used for optical elements.

Hereinafter, some examples will be shown in order to explain the present invention more concretely. However, the scope of the present invention is not limited to the scope of these examples.

<Optical DSC measurement>
In this example, the optical DSC measurement was performed as follows. As the DSC measuring device, an XDSC-7000 manufactured by Hitachi High-Tech Co., Ltd. was used, and an optical DSC measuring unit was attached to the DSC-7000 so that DSC measurement could be performed while irradiating light.

As the light source for light irradiation, LA-410UV manufactured by Hayashi Clock Industry Co., Ltd. was used, and 405 nm light or 365 nm light was extracted by a bandpass filter so that the sample could be irradiated. The illuminance of the light was 50 mW / cm ² or 10 mW · cm ² . The light from the light source was guided to the upper part of the sample using glass fiber, and the shutter of the light source could be triggered and controlled so that DSC measurement could be performed at the same time as the start of light irradiation.

For the measurement of optical DSC, a sample was precisely weighed in an aluminum pan for measurement of about 1 mg, stored in the DSC measuring unit, and then the optical DSC unit was attached. After that, the inside of the measuring part was kept in a nitrogen atmosphere and allowed to stand for 5 minutes to start the measurement. The measurement was continued for 10 minutes while irradiating with normal light. After the first measurement, the sample was left as it was, and the measurement was performed again under the same conditions, and the value obtained by subtracting the second measurement result from the first measurement result was taken as the measurement result of the sample. Unless otherwise specified, the results were compared based on the total calorific value per 1 mg of the sample 2 minutes after light irradiation. Depending on the measurement conditions, the photoreaction may not be completed in 2 minutes, but in order to compare the reaction behavior at the initial stage of light irradiation, the total calorific value for 2 minutes was compared.

When the sample (photopolymerizable composition) is polymerized by light irradiation, the reaction heat is generated by the polymerization, and the reaction heat can be measured by the optical DSC. Therefore, the state of polymerization progress due to light irradiation can be measured by optical DSC. In this example, the total calorific value for 2 minutes after light irradiation was measured, and the polymerization rate (%) was calculated using the theoretical calorific value of the sample obtained from the molar polymerization heat of the monomer. It can be considered that the larger the polymerization rate, the more efficiently the polymerization proceeds.

"Example 1"
0.1 parts by weight of di-t-butyl fumarate as a fumaric acid ester compound, 0.4 parts by weight of N-methylpyrrolidone as a solvent, and 2,4,6-trimethylbenzoyldiphenylphosphine as a photopolymerization initiator. 0.005 parts by weight of oxide (trade name "Irgacure TPO", manufactured by BASF) was mixed at room temperature with stirring until the solid content disappeared to obtain a photopolymerizable composition. About 1 mg of the photopolymerizable composition is precisely weighed, placed in an aluminum pan for measurement, and the optical DSC of the photopolymerizable composition is irradiated with light having ^{a wavelength of 405 nm and an illuminance of 50 mW / cm 2.} Measurements were made. The polymerization rate (%) was calculated from the calorific value of the photopolymerizable composition 2 minutes after irradiation and the heat of molar polymerization of the fumaric acid ester compound. The results are shown in Table 1.

"Examples 2 to 6"
As the fumarate ester compound, bis (2-ethylhexyl) fumarate was used in Example 2 instead of di-t-butyl fumarate in Example 1, and ethyl-t-butyl fumarate was used in Example 3 instead of di-t-butyl fumarate. The same as in Example 1 except that di-i-butyl fumarate was used, di-i-propyl fumarate was used in Example 5, dibutyl fumarate was used in Example 6, and monoethyl fumarate was used in Example 7. Then, optical DSC measurement was performed. The results are shown in Table 1.

"Comparative Example 1"
The composition was prepared in the same manner as in Example 1 except that -i-butyl acrylate was used instead of the fumaric acid ester compound in Examples 1 to 7, and optical DSC measurement was performed under the same conditions. The results are shown in Table 1.

As is clear from comparing Examples 1 to 6 with Comparative Example 1, the polymerization rate of the fumaric acid ester compound for 2 minutes is larger or equivalent in all examples as compared with the acrylic acid ester of Comparative Example. Understand. Therefore, even a fumaric acid ester compound having an alkyl chain having a simple ester moiety structure of the present invention has a high polymerization rate as well as an acrylic acid ester such as acrylic acid-i-butyl which is preferably used as a polymer raw material. Ester homopolymers can be produced.

Claims (1)

A photopolymerizable composition containing at least a fumaric acid ester compound having a simple alkyl chain represented by the general formula (1) as an ester moiety and a photopolymerization initiator can be obtained from 385 nmUV-LED, 395 nmUV-LED or 405 nmUV-LED. A method for producing a fumaric acid ester homopolymer, which comprises photopolymerizing by irradiating with energy rays using the above as a single light source.

(In the general formula ^(1), R 1, ^{R 2} represents an alkyl group having from carbon number 2 4.)