JPS5952648B2 - Modified polybutadiene composition with photocurability - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photocurable modified polybutadiene composition that can be cured by ultraviolet irradiation and is particularly useful as a coating varnish for metals and plastics such as alkyd resins.

Conventionally, heat curing and drying methods have been used to coat metals, but this method releases large amounts of organic solvents into the atmosphere during drying, which poses problems not only from the standpoint of pollution control but also from the standpoint of resource conservation. There is.

As a method for improving the drawbacks of this heat curing drying method, an ultraviolet curing drying method using a photocurable composition as a coating material has been developed. Regarding polybutadiene-based photocurable compositions, a photocurable composition consisting of an esterified modified product in which acrylic acid is added to the epoxy group of epoxidized polybutadiene, a photopolymerizable monomer, and a photosensitizer has been proposed. (Japanese Unexamined Patent Publication No. 51-37128), but it takes a long time for photocuring and drying and is not practical. The inventors completed this invention as a result of intensive research to improve the above-mentioned drawbacks of known polybutadiene photocurable compositions.

This invention has a number average molecular weight of 500 to 5000,
Epoxidized polybutadiene obtained by epoxidizing liquid polybutadiene having a viscosity (30°C) of 20 to 10,000 is reacted with (a) a (meth)acrylate containing a hydroxyalkyl group and an aromatic carboxylic acid anhydride. The monoester compound that is the product and (a) hydrogen chloride or aliphatic lower carboxylic acid are added to the butadiene constituent unit of the epoxidized polybutadiene in an amount of (a) of 0.03 to 0.03 to
100 parts by weight of modified polybutadiene obtained by adding 0.2 pieces and 0.05 to 0.3 pieces, 30 to 200 parts by weight of photopolymerizable monomer, and 0.5 to 15 parts by weight of photosensitizer. The present invention relates to a modified polybutadiene composition (hereinafter abbreviated as photocurable composition) containing 5% of photocurable composition.

The photocurable composition of the present invention has excellent photocuring drying properties, and the cured coating film has excellent properties such as adhesion to metals and plastics such as alkyd resins, bending resistance, impact resistance, and water resistance. It has the feature of being Modified polybutadiene, which is a component of this invention, can also be produced by adding hydrogen chloride or aliphatic lower carboxylic acid to epoxidized polybutadiene, and then adding a monoester compound. Since the compound is difficult to add compared to hydrogen chloride and aliphatic lower carboxylic acid, it is preferable to produce it by adding a monoester compound to epoxidized polybutadiene and then adding hydrogen chloride or aliphatic lower carboxylic acid. preferable.

The liquid polybutadiene has a number average molecular weight of 500 to 5.
000, preferably 600-3000, viscosity (30°C)
It is a liquid polybutadiene having 20 to 10,000 CP (centiboads), preferably 30 to 5,000 CP (centiboads), and its microstructure is not particularly limited, but 40% or more of the butadiene structural units have a 1,4-structure, and the 1,
It is preferable that 70% or more of the 4-structure has a cis structure.

The liquid polybutadiene mentioned above is not only a butadiene homopolymer but also contains 70% butadiene units based on the total monomer units.
Copolymers of butadiene having the above and acrylonitrile, styrene, (meth)acrylic acid ester, vinyl acetate, isoprene, 1,3-pentadiene, maleic anhydride, etc. are included. Moreover, the liquid polybutadiene may have a hydroxyl group, a carboxyl group, or other functional group at the end. Liquid polybutadiene. If the number average molecular weight and viscosity of the composition are lower than the above-mentioned lower limit, the photocurable drying properties of the photocurable composition will be poor, and the impact resistance of the cured coating film will be poor, which is not preferable. Moreover, if the number average molecular weight and viscosity of the liquid polybutadiene are larger than the above upper limit, the viscosity of the photocurable composition becomes large, making it difficult to use it as a coating varnish, which is not preferable. The epoxidized polybutadiene is produced by subjecting the liquid polybutadiene to an epoxidation reaction with hydrogen peroxide and an aliphatic lower carboxylic acid such as formic acid or acetic acid in an organic solvent at 30-40°C for several hours. Ru.

When reacting liquid polybutadiene with hydrogen peroxide and aliphatic lower carboxylic acid, the molar ratio of hydrogen peroxide to aliphatic lower carboxylic acid is 1 to 10, especially 2 to 10.
6, and it is preferable that the ratio of hydrogen peroxide to liquid polybutadiene is 2 to 5 by weight.Epoxidized polybutadiene is produced by mixing liquid polybutadiene and peracetic acid in the presence of sodium acetate. The epoxidation reaction is carried out in a solvent at about 50°C for several hours.
958).

After the epoxidation reaction is completed, the reaction product mixture is washed with water to remove excess hydrogen peroxide or water-soluble compounds such as peracetic acid, and then the organic solvent is distilled off to isolate the epoxidized polybutadiene. . The number of epoxy groups in the epoxidized polybutadiene is 0.08 to 0.5, particularly 0.15 per butadiene constituent unit of the epoxidized polybutadiene.
~0.45 pieces is preferable. The monoester compound added to the epoxidized polybutadiene is an equimolar reaction product of a (meth)acrylate containing a hydroxyalkyl group having 2 to 16 carbon atoms and an aromatic carboxylic acid anhydride.

The (meth)acrylate containing a hydroxyalkyl group includes 2-hydroxyethyl acrylate,
Examples include 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, polyethylene glycol monoacrylate, polyethylene glycol monomethacrylate, polypropylene glycol monoacrylate, polypropylene glycol monomethacrylate, pentaerythritol triacrylate, etc. be able to.
The aromatic carboxylic acid anhydride has one carboxylic anhydride ring.
The hydrogen atom of the benzene ring may be substituted with another substituent.

Examples of the substituent include a halogen atom, an alkoxyl group, an alkyl group, an alkylthio group, a hydroxy group, a nitro group, and a methylenedioxy group. Examples of aromatic carboxylic anhydrides include phthalic anhydride, trimellitic anhydride, 3-chlorophthalic anhydride, 3,6-dichlorophthalic anhydride, 4-chlorophthalic anhydride, 4,5-dichlorophthalic anhydride, and tetrachlorophthalic anhydride. Phthalic anhydride, 3-
Fluorophthalic anhydride, 3,6-difluorophthalic anhydride, 3-monoiodophthalic anhydride, 3,6-diiodophthalic anhydride, 4-monoiodophthalic anhydride, 4,5-diiodophthalic anhydride acid, tetraiodophthalic anhydride, 3-bromo phthalic anhydride, 3,6-dibromo phthalic anhydride, 4
-Bromophthalic anhydride, 4,5-dibromo phthalic anhydride, tetrabromo phthalic anhydride, 3-fluorophthalic anhydride, 3,6-difluorophthalic anhydride, 4-fluorophthalic anhydride, 4,5-difluorophthalic anhydride, 3
, 4-dimethoxyphthalic anhydride, 3,6-dimethoxyphthalic anhydride, 4,5-dimethoxyphthalic anhydride, 3
-(dimethylmethyl)phthalic anhydride, 3-ethyl-6
(Ethylthio) monophthalic anhydride, 3-(ethylthio)phthalic anhydride, 3,5-dimethoxy-4-methylphthalic anhydride, 4,6-dimethoxy-3-methylphthalic anhydride, 3,6-dihydroxyphthalic anhydride acid, 3,6-
Dihydroxy-4-methyl phthalic anhydride, 3,6-dimethoxy-4,5-methylenedioxy phthalic anhydride,
3,4-dimethyl phthalic anhydride, 3,6-dimethyl phthalic anhydride, 4,5-dimethyl phthalic anhydride, 3-methyl-6(methylthio) phthalic anhydride, 3-methyl-phthalic anhydride, 4 -Methyl phthalic anhydride, 3-methoxy phthalic anhydride, 4-methoxy phthalic anhydride, 3
-methoxy-4,6-dimethylphthalic anhydride, 4isopropyl-3,5,6,monotrimethoxyphthalic anhydride,
4-Hydroxyphthalic anhydride, 3hydroxy-4,6-
Dimethyl phthalic anhydride, 3(ethylthio)-6-methyl phthalic anhydride, 5(ethylthio)-3-methyl phthalic anhydride, 3-hydroxy-4-methoxy phthalic anhydride,
3-hydroxy-5-methoxy phthalic anhydride, 6-hydroxy-4-methoxy-3-methyl phthalic anhydride,
6-isobutyl-3,4-dimethylphthalic anhydride, 3
-Methyl-5-(phenylthio)phthalic anhydride, 3-(
methylthio) phthalic anhydride, 3-nitro phthalic anhydride,
Examples include 4-nitrophthalic anhydride, 3-(phenylthio)phthalic anhydride, 3-propyl phthalic anhydride, and 3-(propylthio) phthalic anhydride. The monoester compound is prepared by combining a (meth)acrylate containing one or more hydroxyalkyl groups as described above and one or more aromatic carboxylic acid anhydrides in the presence of a catalyst. , 70-1 without solvent or in organic solvent
It is produced by carrying out a monoesterification reaction at 00°C for 2 to 7 hours.

In the above monoesterification reaction, it is preferable to add a small amount of a known suitable thermal polymerization stabilizer such as hydroquinone, 2,6-di-tert-butyl-para-cresol, or para-benzoquinone for the purpose of preventing gelation. . Further, examples of the catalyst used in the monoesterification reaction include organic quaternary ammonium salts such as triethylbenzylammonium chloride, methyltriethylammonium chloride, tetraethylammonium talolide, and methyltriethylammonium iodide. It is preferable that the molar ratio of the (meth)acrylate containing a hydroxyalkyl group to the aromatic carboxylic acid anhydride is 1 or more. In the monoesterification reaction described above, the monoesterification reaction mixture after removing the solvent and the terminally reacted (meth)acrylate was subjected to infrared absorption vector analysis to determine the aromatic carboxylic anhydride ring possessed by the aromatic carboxylic anhydride. absorption peak (1760-1780
cm-1 and 1840 to 1860 cm-1) are exhausted. Addition of a monoester compound to epoxidized polybutadiene is performed using a monoester compound which is a reaction product of the epoxidized polybutadiene obtained as described above, a (meth)acrylate containing a hydroxyalkyl group, and an aromatic carboxylic acid anhydride. This reaction can be carried out by reacting a compound with a compound in the presence of a catalyst such as the organic ammonium salt, without a solvent or in an organic solvent, at 70 to 80°C for 6 to 8 hours.

The ratio of the epoxidized polybutadiene to the monoester compound is preferably 80 to 300 parts by weight and 7 parts by weight per 100 parts by weight of the epoxidized polybutadiene. By the method described above, 0.03 to 0.2 monoester compounds can be added per butadiene constituent unit of the epoxidized polybutadiene. If the number of monoester compounds added to the epoxidized polybutadiene is less than the lower limit θ, it will take a long time to photocure and dry the photocurable composition, and the impact resistance and water resistance of the cured coating will deteriorate. So I don't like it. Furthermore, if the number of monoester compounds added is greater than the above upper limit, the viscosity of the photocurable composition increases, making it difficult to use it as a varnish for coating metals or plastics, which is not preferred. Modified polybutadiene, which is a component of this invention, is produced by adding hydrogen chloride or an aliphatic lower carboxylic acid to the reaction mixture after adding a monoester compound to epoxidized polybutadiene, and adding the monoester compound to the epoxidized polybutadiene. It can be obtained by adding hydrogen chloride or aliphatic lower carboxylic acid.

Examples of the aliphatic lower carboxylic acids include formic acid and acetic acid. In order to add hydrogen chloride to epoxidized polybutadiene to which a monoester compound has been added, hydrogen chloride is added to the reaction mixture at an equivalent ratio of 0.5 to 1. It is preferable to stir and mix the reaction solution obtained by adding 0 times as much hydrogen chloride at 20 to 50°C for 0.5 to 2 hours. In addition, in order to add an aliphatic lower carboxylic acid to epoxidized polybutadiene to which a monoester compound has been added, an aliphatic lower carboxylic acid is added to the reaction mixture in an equivalent ratio of 1 to 2 times the remaining epoxy groups. It is preferable to stir and mix the resulting reaction solution at 30 to 70°C for 5 to 10 hours. By the above-mentioned method, 0.05 to 0.3 hydrogen chloride or aliphatic lower carboxylic acid can be added per butadiene constituent unit of the epoxidized polybutadiene to which a monoester compound has been added. If the number of hydrogen chloride or aliphatic lower carboxylic acids added is less than the above-mentioned lower limit, the photocurable drying properties of the photocurable composition and the adhesion of the cured coating film to metals and plastics will deteriorate, which is not preferred. Even if the number of hydrogen chloride or aliphatic lower carboxylic acids added is larger than the above upper limit, the photocurable composition
This is not preferred because the photocurable drying properties and the adhesion of the cured coating film to metals and plastics remain unchanged, making it uneconomical. After completion of the addition reaction, the mixture is washed with water and then distilled under reduced pressure to remove the solvent to obtain a mixture of modified polybutadiene and monoester compound. The photopolymerizable monomer that is one component of the photocurable composition of the present invention is preferably a (meth)acrylic ester having a boiling point of 200° C. or higher at normal pressure.

Photopolymerizable monomers include those containing hydroxyalkyl groups such as 2-hydroxyethyl (meth)acrylate and 2-hydroxypropyl (meth)acrylate.
(meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, ) Acrylate, polyethylene glycol mono(meth)acrylate, degree of polymerization 1 to 8
6 polypropylene glycol mono(meth)acrylate, propylene glycol di(meth)arylate,
Dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, tetrapropylene glycol di(meth)acrylate, 1,
3-butylene glycol di(meth)acrylate, 1
, 4-butylene glycol di(meth)acrylate,
Examples include 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, and pentaerythritol tri(meth)acrylate. Furthermore, a monoester compound which is a reaction product of a (meth)acrylate containing a hydroxyalkyl group and an aromatic carboxylic acid anhydride can be used as a photopolymerizable monomer. In this invention, the photosensitizers include benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin butyl ether, benzoin, α-methylbenzoin, α-chlorodioxybenzoin, benzophenone, diethoxyacetophenone, dimethoxyphenyl Acetophenone, benzyl, etc. can be used.

In the photocurable composition of the present invention, the amount of the photopolymerizable monomer is 30 to 200 parts by weight, preferably 50 to 18 parts by weight, based on 100 parts by weight of the modified polybutadiene.
It is 0 parts by weight.

If the amount of the photopolymerizable monomer is less than the lower limit, the viscosity of the photocurable composition increases, making it difficult to use it as a varnish for coating metals or plastics, which is not preferable. If the amount of the photopolymerizable monomer is more than the above upper limit, the impact resistance of the cured coating film of the photocurable composition will deteriorate, which is not preferable. In the photocurable composition of this invention,
The amount of the photosensitizer to be blended is 0.5 to 15 parts by weight, preferably 2 to 10 parts by weight, based on 100 parts by weight of the modified polybutadiene.

If the amount of the photosensitizer is less than the above-mentioned lower limit, it is not preferable because it takes a long time for photocuring and drying of the photocurable composition. Even if the amount of the photosensitizer is more than the above-mentioned upper limit, the photosensitization effect remains the same and it becomes uneconomical, which is not preferable. In the photocurable composition of the present invention, hydroquinone, 2,6-di-tert-butyl para-cresol, para-benzoquinone, etc. can be used as a thermal polymerization stabilizer.

When a thermal polymerization stabilizer is added, the photocurable drying properties of the photocurable composition deteriorate, so it is preferable that the amount of the thermal polymerization stabilizer added is kept to a very small amount. A suitable amount of the thermal polymerization stabilizer added is 5 parts by weight or less per 100 parts by weight of the photocurable composition. The photocurable composition of the present invention can be blended by conventionally known blending methods.

For example, a photocurable composition can be prepared by adding only a photosensitizer or a photosensitizer and an additional photopolymerizable monomer to the mixture of the modified polybutadiene and monoester compound. Obtainable. The photocurable composition of the present invention is a colorless or slightly yellow liquid, and has a viscosity of 100 to 2000 CP (30°C), particularly 150 to 130 CP.
It is preferable that it is 0CP (30 degreeC). The photocurable composition of this invention can be used as it is as a varnish for coating metals and plastics such as alkyd resins, but in order to improve the slip properties of the coating film, it can be used as a varnish for coating plastics such as stearamide and oleic acid amide. A small amount of fatty acid amide or wax such as carnauba wax, ozokerite wax, or spam acetiwax may be added.

The photocurable composition of the present invention also contains styrene, vinyltoluene, vinyl acetate, methyl methacrylate, acrylic acid, methacrylic acid, benzene, toluene, xylene, tamene, hexane, cyclohexane,
A small amount of ethyl acetate, kerosene, methyl isobutyl ketone, etc. may be added. Examples, comparative examples, and reference examples are shown below.

In the reference example, the number of epoxy groups in epoxidized polybutadiene is determined by adding an appropriate amount of epoxidized polybutadiene to hydrochloric acid.
It was added to a dioxane solution for chlorination, and excess hydrochloric acid was determined by titration with alcoholic potassium using phenolphthalene as an indicator.

The number of monoester compounds added to the epoxidized polybutadiene was determined by measuring the difference in acid value of the reaction mixture of the epoxidized polybutadiene and the monoester compound before and after the reaction. The number of aliphatic lower carboxylic acids added to epoxidized polybutadiene to which a monoester compound has been added is determined by the reaction mixture after adding a monoester compound to epoxidized polybutadiene, and the mixture of a monoester compound and modified polybutadiene. It was determined by measuring the difference in the number of epoxy groups. In Examples, Comparative Examples, and Reference Examples, the viscosity was measured using an E-type viscometer manufactured by Tokyo Keiki Co., Ltd. In the Examples and Comparative Examples, the photocurable drying properties of the photocurable compositions were determined by applying the photocurable composition to a thickness of about 10 μm on a degreased aluminum plate using a 2KW high-pressure mercury lamp with a length of 25 cm ( Vertical lower 9c (manufactured by Iwasaki Electric Co., Ltd.)
The photocurable composition coating film is placed on the belt of an ultraviolet irradiator equipped with a belt that moves horizontally at a predetermined speed, and Saran Wrap is applied to the surface of the photocured composition coating film. (manufactured by Asahi Tau Co., Ltd., registered trademark), and after peeling off the Saran Wrap, observe the cloudiness of the coating film surface, and check the maximum belt feed speed (m/ Min).

The adhesion of the cured coating film was determined by making straight cuts of 2 mm width in each direction in the coating film on the aluminum plate or alkyd resin plate obtained by photocuring under the same conditions as those used to measure the photocuring drying property. Make 100 gobang stitches using zero tape (
(registered trademark) was applied, the tape was then peeled off, and the number of gobbles remaining on the aluminum plate or alkyd resin plate was shown.

The pencil hardness of the cured coating film was determined using JIS-K54OO6. Measured according to 14.

Samples for measuring the bending resistance and Dupont impact strength of cured coatings were placed on iron plates specified in JIS-K54OO, and coatings for measuring water resistance were placed on glass plates.
Apply to a thickness of 0μ and apply at a belt feed speed of 1m/min.
Obtained by photocuring.

Flexibility is JIS-K54OO6. The Dupont impact strength was measured according to JIS-K54OO6. 13, and water resistance is determined by soaking a cured coating piece in warm water at 40°C for 1 hour, with no wrinkles, creases, or blisters observed on the coating surface.
If there is a slight decrease in gloss or cloudiness, mark it as ○, and the wrinkles will be removed.
Items with blistering, decreased luster, and a large degree of cloudiness are marked with an x. Ta. In the descriptions of Reference Examples, Examples, and Comparative Examples, parts mean parts by weight, and the meanings of abbreviations are as follows.

Epoxidized PB: epoxylated monoester compound of liquid polybutadiene; modified polybutadiene, a reaction product of a (meth)acrylate containing a hydroxyalkyl group and an aromatic carboxylic acid anhydride; a monoester compound of epoxidized polybutadiene, and hydrogen chloride or Aliphatic lower carboxylic acid adduct 2HEA; 2-hydroxyethyl acrylate 2EHA; 2-ethylhexyl acrylate 16HDA; 1,6-hexanediol diacl)
:Rate PHEA; Reaction product of phthalic anhydride and 2-hydroxyethyl acrylate THEA; Reaction product of trimellitic anhydride and 2-hydroxyethyl acrylate NHEA; 4-nitrophthalic anhydride and 2-hydroxyethyl acrylate Reference Example 1 (Production of Epoxidized PB) 500 parts of liquid polybutadiene having the molecular weight, viscosity, and microstructure shown in Table 1 was added to 1300 parts of benzene, and 30 parts of the amount shown in Table 1 was added to 1300 parts of benzene. % concentration aqueous hydrogen peroxide solution and to the resulting suspension was added the first
Formic acid in the amount shown in the table was added dropwise at 20° C. over about 30 minutes.

Thereafter, the reaction was carried out at about 35° C. for 5 hours, and after the reaction was completed, the reaction solution was washed with water, and benzene was removed by vacuum distillation to obtain epoxidized PB. Table 1 shows the number of epoxy groups (number of epoxy groups per butadiene constituent unit of epoxidized PB), viscosity, and yield of this epoxidized PB. Reference Example 2 (Manufacture of monoester compound) Aromatic carboxylic acid anhydride of the type and amount shown in Table 2 was added to 116 parts of 2-hydroxyethyl acrylate, and further 2,6-di-tert-butyl-para-cresol was added. 0.3 parts and 0.4 parts of triethylbenzylammonium chloride
After adding 5 parts, the reaction was carried out at 95° C. for 5 hours with stirring.

After the reaction, unreacted 2-hydroxyethyl acrylate was removed by vacuum distillation, and the absorption peaks of the carboxylic acid ring of the aromatic carboxylic anhydride (1770 cm, 1850 cm) were determined by infrared absorption spectroscopy. A monoester compound was obtained.The yield of this monoester compound is shown in Table 2.Reference Example 3 (Production of modified polybutadiene) Epoxidized P of the type shown in Table 3 was added to 280 parts of benzene.
42 parts of Bl and a monoester compound of the type and amount shown in Table 3 were added, and further 2,6-di-tert-butyl-para-
After adding 0.8 parts of cresol and 0.8 parts of triethylbenzylammonium chloride, the mixture was heated to 75°C.
8 hours (4 hours for experiment number M-6)
Made it react.

After the completion of the reaction, except for experiment number M-1, add hydrogen chloride (2 N methanol solution) or formic acid to the reaction mixture in the amount shown in Table 3, and in the case of hydrogen chloride addition, add about 2
In the case of formic acid addition, the reaction was carried out at 50° C. for about 10 hours. After the reaction was completed, the mixture was washed with water, and then low-boiling substances were removed by vacuum distillation to obtain a mixture containing modified polybutadiene. Table 3 shows the number of monoester compounds added, the number of hydrogen chloride or formic acid added to the modified polybutadiene, and the composition and viscosity of the mixture containing the modified polybutadiene. Reference example 3
To the mixture containing the modified polybutadiene in the amount shown in Table 4 obtained in Table 4, add the photopolymerizable monomer of the type and amount shown in Table 4 and the mixture containing the modified polybutadiene and the photopolymerizable monomer. A photocurable composition was prepared by adding 5 parts of benzoin methyl ether to 100 parts.

Table 4 shows the viscosity and drying properties of the photocurable composition obtained, and the pencil hardness, adhesion, bending resistance, Dupont impact strength and water resistance of the photocured product. Reference Example 4 (Manufacture of modified polybutadiene) 100 parts of liquid polybutadiene of the same type as used in Experiment No. E-1 of Reference Example 1 was added to 170 parts of benzene,
Further, 209 parts of a 30% hydrogen peroxide aqueous solution was added, and after adding 1 part of 95% sulfuric acid to the resulting suspension, 660 parts of acetic acid was added with stirring.

Thereafter, the reaction was carried out at about 35°C for 12 hours, and after the reaction was completed, the reaction solution was allowed to cool, washed with water, and benzene was removed by vacuum distillation.
An epoxidized PBllO portion to which acetic acid was added was obtained. The number of acetic acids added to the epoxidized PB to which this acetic acid was added is 0.07 (
The number of epoxy groups was 0.18 per butadiene structural unit (the same applies hereinafter), and the viscosity was 31,000 CP (30° C.).
The obtained epoxidized PB2O portion to which acetic acid was added, the monoester compound obtained in Experiment No. R-1 of Reference Example 2 (P
17.4 parts of HEA), 0.2 parts of 2,6-di-tert-butyl-para-cresol, and 0.2 parts of triethylbenzylammonium chloride were added to 50 parts of benzene, and the mixture was stirred at about 70°C for 10 hours. Made it react. After the reaction was completed, benzene was removed by vacuum distillation to obtain 37.6 parts of a mixture containing modified polybutadiene. The number of monoester compounds (PHEA) added to this modified polybutadiene is 0.
08, the number of additions of acetic acid is 0.07, and the viscosity of the mixture containing modified polybutadiene is 41000 CP (30 ° C.),
The composition of the mixture containing modified polybutadiene is Mixture 10
Of the 0 parts by weight, 74 parts of the modified polybutadiene and 26 parts of the monoester compound were contained. Example 15 Mixture 1 containing modified polybutadiene obtained in Reference Example 4
The same procedure as in Example 1 was carried out except that 00 parts were used.

The resulting photocurable composition had a viscosity of 1200 CP (30°C
), photocurable drying property 30m/Min, and photocured product,
Pencil hardness H, adhesion 100 (aluminum plate), 100
(Plastic ivy board), bending resistance 2mmφ, Dupont impact strength 150 (500g x 1/2'' x Cm), water resistance ○
It was hot. Comparative Example 1 The same procedure as in Example 1 was carried out except that 146 parts of the mixture M-1 containing modified polybutadiene was used instead of the mixture M-2 containing modified polybutadiene.

Viscosity of photocurable composition 250CP (30°C), photocuring drying property 10m/Min, pencil hardness HB of photocured product, adhesion (aluminum plate) 80, bending resistance 2mmφ, DuPont impact strength 80 (500g x 1 /2″″×Cm), and the water resistance was x. Comparative Example 2 Molecular weight 1530, viscosity 800CP (30°C), microstructure 1,2; 54%, cis-1,4; 37%, trans-1
, 4; 100 parts of epoxidized polybutadiene having 0.06 epoxy groups per butadiene constituent unit of the epoxidized polybutadiene obtained by epoxidizing liquid polybutadiene having 9%, methacrylic acid 12 part and 0.1 part of hydroquinone in 20 parts of benzene.
After adding 0 parts, the mixture was reacted at 60° C. for 3 hours.

After the reaction was completed, benzene and unreacted methacrylic acid were removed by vacuum distillation to obtain 105 parts of a reaction product. 10 parts of 1,3-butylene glycol diacrylate and 1 part of benzyl were blended with 100 parts of this reaction product to obtain a photocurable composition. This photocurable composition has a viscosity of 4000
CP (30℃), photocuring drying belt feeding speed 5m
/Min was not cured. Comparative Example 3 2 parts of triethylbenzylammonium chloride, 0.1 part of hydroquinone, and 0.1 part of anthraquinone were added to a mixture of 58 parts of 2-hydroxyethyl acrylate and 74 parts of phthalic anhydride, and the mixture was reacted at 110°C for 5 hours. A monoester compound was synthesized.

Claims (1)

[Claims] 1 Number average molecular weight is 500 to 5000, viscosity (3
Epoxidized polybutadiene obtained by epoxidizing liquid polybutadiene with a temperature of 20 to 10,000 (0°C),
(a) A monoester compound which is a reaction product of a (meth)acrylate containing a hydroxyalkyl group and an aromatic carboxylic acid anhydride, and (b) hydrogen chloride or an aliphatic lower carboxylic acid, and a butadiene of epoxidized polybutadiene. 100 parts by weight of modified polybutadiene obtained by adding 0.03 to 0.2 of (a) and 0.05 to 0.3 of (b), and 30 to 20 parts of photopolymerizable monomer per structural unit.
A photocurable modified polybutadiene composition containing 0 parts by weight and 0.5 to 15 parts by weight of a photosensitizer.