Sulfur atom-containing (meth)acrylic acid ester and polymer

Abstract

To provide a novel sulfur atom-containing (meth)acrylic acid ester.SOLUTION: The sulfur atom-containing (meth)acrylic acid ester is represented by the general formula (1) in the figure. (In the formula, n is from 3 to 6; and R2 represents hydrogen or a methyl group.)SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a sulfur atom-containing (meth)acrylate ester having a specific structure and a polymer.

Background Art

[0002] As (meth)acrylate esters used as raw materials for acrylic resins and energy ray-curable resin raw materials, extremely many types have been studied, and much research has also been conducted on novel compounds for obtaining desired physical properties.

[0003] As one of such compounds, examination has been made on acrylic acid ester compounds having a benzothiazole ring (Patent Documents 1 to 4, etc.). Such compounds are expected to have high refractive performance derived from their structures and an effect of improving adhesion to metals.

[0004] In particular, Patent Document 1 describes a compound represented by the following general formula (2).

Chemical Formula

[0005] However, the above compound in Patent Document 1 is described as a comparative example and does not have a predetermined effect intended in Patent Document 1.

[0006] In the technologies described in the above-cited documents, in any case, complicated synthesis methods, expensive raw materials, or raw materials having a specific odor must be used, and there are many problems in industrialization. Furthermore, the properties of these compounds are derived from their structures, but generally, they are often solids or have extremely strong odors. Therefore, there is a demand for a compound that has the performance derived from the above structure and is a liquid with an improved odor.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0008] An object of the present invention is to provide a novel sulfur atom-containing (meth)acrylate that solves the above-described problems.

Means for Solving the Problems

[0009] The present invention is a sulfur atom-containing (meth)acrylate represented by the following general formula (1).

Chemical Formula

Effects of the Invention

[0010] The sulfur atom-containing (meth)acrylate of the present invention has a high refractive index, little odor, and is a liquid, so it has the effect of being excellent in handleability. Furthermore, an effect as an adhesion-imparting agent is also expected.

Modes for Carrying Out the Invention

[0011] Hereinafter, the present invention will be described in detail. The (meth)acrylate of the present invention is represented by the following general formula (1).

Chemical Formula

[0012] In the above general formula (1), n = 3 to 6, and R2 is hydrogen or a methyl group. As a known compound similar to the compound represented by the above general formula (1), there is one in which n = 2 in the above general formula. When comparing such a compound with the compound of the present invention, effects such as improvement in odor and good handleability because the compound is liquid at room temperature can be obtained.

[0013] The method for producing the compound represented by the above general formula (1) is not particularly limited. Specifically, for example, it can be synthesized by performing the following two-step reaction on the mercapto compound (2) represented by the following general formula.

[0014]

Chemical formula

[0015]

Chemical formula

[0016] The first-stage reaction is a reaction between a mercapto compound and a halogen compound, and can be carried out under known reaction conditions. Known compounds can be used as the compounds serving as raw materials for the above reaction.

[0017] The compound represented by the above general formula (3) is a compound in which different halogen atoms are bonded to both ends of a linear hydrocarbon group having n corresponding to the target compound. When different halogen atoms are bonded to both ends, the reactivity of the chemical reaction represented by the above general formula differs for each halogen atom. And it is preferable in that the more reactive halogen reacts preferentially and the compound represented by the above general formula (4) can be obtained without causing side reactions.

[0018] The combination of the above X1 and X2 is not particularly limited, and two kinds can be selected from fluorine, chlorine, bromine, and iodine. However, the combination of chlorine and bromine can be most preferably used. In the case of the combination of chlorine and bromine, the reaction proceeds with X1 = Cl and X2 = Br.

[0019] The reaction in the second stage is a reaction between the compound represented by the general formula (4) and the (meth)acrylate, and can be carried out under known reaction conditions. All the compounds used as raw materials for the above reaction are known compounds, and commercially available products or those obtained by general synthetic methods can be used.

[0020] The above (meth)acrylate is not particularly limited. For example, alkali metal salts such as potassium salts and sodium salts can be preferably used, and potassium salts are most preferred.

[0021] When carrying out the above reaction, it is preferable to use both components in approximately equivalent amounts. More specifically, it is preferable to mix the halogen compound (intermediate) / (meth)acrylic acid at a ratio of 1 / 1 to 1 / 1.5 (molar ratio). The above ratio is more preferably 1 / 1 to 1 / 1.3, and even more preferably 1 / 1 to 1 / 1.1.

[0022] When carrying out the above reaction, a phase transfer catalyst may be used to facilitate the progress of the reaction. Examples of phase transfer catalysts include quaternary ammonium salts and crown ethers. More specifically, from the perspective of easy availability of industrial raw materials, tetramethylammonium chloride, triethylmethylammonium chloride, ethyltrimethylammonium chloride, methyltributylammonium chloride, methyltrioctylammonium chloride, benzyltrimethylammonium chloride, benzyltriethylammonium chloride, benzyltributylammonium chloride, trimethylstearylammonium chloride, hydroxyethyltrimethylammonium chloride, triethylmethylammonium bromide, tetraethylammonium bromide, ethyltrimethylammonium bromide, tetrabutylammonium bromide and other quaternary ammonium salts are preferred. These phase transfer catalysts may be used alone or in combination of two or more. Also, they can be used in an aqueous solution.

[0023] When using the above phase transfer catalyst, its usage amount is preferably in the range of 0.1 to 10% by weight based on the total weight of the reaction raw materials. By setting it within this range, the reaction can proceed favorably.

[0024] When carrying out the above reaction, in order to prevent the polymerization of the (meth)acrylic acid derivative due to heating during the reaction, a conventional polymerization inhibitor can be used. Representative examples include, but are not limited to, polymerization inhibitors such as quinones, alkylphenols, and amines.

[0025] The above reaction can be carried out in a solution of any organic solvent that dissolves the raw materials and reaction products. The solvent to be used is not particularly limited. For example, it is preferably carried out in an aprotic solvent. In an aprotic solvent, the SN2 reaction proceeds efficiently, so it is preferred. The aprotic solvent is not particularly limited. Specifically, for example, N-methylpyrrolidone, dichloromethane, tetrahydrofuran, ethyl acetate, acetone, dimethylformamide, acetonitrile, dimethyl sulfoxide, propylene carbonate, etc. can be mentioned. The total amount of the raw material compounds added to the solvent is preferably in the range of 20 to 80% by weight. By setting it within such a range, the reaction can be carried out efficiently and the effects of the present invention can be obtained.

[0026] The reaction conditions in the production method of the present invention are not particularly limited. For example, it can be carried out by reacting at 60 to 100 °C. The lower limit of the reaction temperature is more preferably 70 °C, and even more preferably 80 °C.

[0027] The reaction product obtained by the method of the present invention is then, depending on the selected production method, filtered by a known method or diluted with a non-polar solvent, and then the desorbed salt is removed by oil-water separation with neutral water, acidic water, or alkaline water, and the solvent is distilled off, etc. By going through such steps, a desired compound with high purity can be obtained.

[0028] The (meth)acrylic acid ester of the present invention can be made into a polymer by copolymerization alone or with other monomers having a polymerizable unsaturated group. Furthermore, the polymer thus obtained can be used as a material such as a paint, an adhesive, or a molding material. The method for producing the polymer is not particularly limited and can be carried out by any known method such as solution polymerization, emulsion polymerization, suspension polymerization, or bulk polymerization. Also, the monomers that can be used in combination are not particularly limited, and known general monomers can be used.

[0029] Also, the (meth)acrylic acid ester of the present invention can be made into an energy ray-curable resin composition alone or as a composition mixed with other polymerizable compounds. Such an energy ray-curable resin composition has the effect of being able to form a film with excellent adhesion and a high refractive index. The other polymerizable compounds that can be used in combination in this case are not particularly limited, and known general polymerizable compounds can be used.

Examples

[0030] Hereinafter, the present invention will be specifically described based on examples. Note that the present invention is not limited to the following examples. In the examples, unless otherwise specified, "parts" and "%" represent "parts by mass" and "mass%".

[0031] Comparative Example 1 Synthesis Example 1 Synthesis of chloromethylthiobenzothiazole (Compound 1) The synthesis operation was carried out according to the following procedure. It was carried out using a small-scale organic synthesis apparatus. In a 50 ml test tube, 4.0 g of 2-mercaptobenzothiazole, 4.0 g of potassium carbonate, and 25 ml of acetone were mixed, and 3.4 g of bromochloromethane was added dropwise with a syringe. After the addition was completed, the mixture was stirred at room temperature for 30 minutes, then heated to 50 °C to complete the reaction. After the reaction was completed, the reaction solution was cooled and allowed to stand, and the precipitate deposited in the reaction solution was removed by suction filtration. The filtrate was concentrated by a rotary evaporator to remove acetone, and 4.8 g (yield 92%) of a reddish-brown transparent liquid was obtained. The obtained compound was 1 1H-NMR (400 MHz, CDCl3) δ: 5.33 (s, 2H), 7.30 (m, 1H), 7.40 (m, 1H), 7.70 (m, 1H), 7.86 (m, 1H). These results supported the target structure.

[0032]

Chemical formula

[0033] Synthesis Example 2 Synthesis of acryloxymethylthiobenzothiazole (Compound 2) It was carried out using a small-scale organic synthesis apparatus. In a 50 ml test tube, 4.0 g of Compound 1, 2.4 g of potassium acrylate, 0.1 g of tetramethylammonium chloride, and 20 ml of DMF were mixed and reacted at 80 °C for 3 hours. After the reaction was completed, appropriate treatment was carried out according to a conventional method to obtain 3.0 g (yield 64%) of a reddish-brown transparent liquid. The obtained compound was 11H-NMR (400 MHz, CDCl3) δ: 5.33 (s, 2H), 5.84 (dd, 1H), 6.10 (dd, 1H), 6.45 (dd, 1H), 7.30 (m, 1H), 7.40 (m, 1H), 7.70 (m, 1H), 7.86 (m, 1H). These results supported the target structure.

[0034] [Chemical formula]

[0035] Comparative Example 2 Synthesis Example 3 Synthesis of 2-chloroethylthiobenzothiazole (Compound 3) The procedure was the same as in Synthesis Example 1, except that 1-chloro-2-bromoethane was used instead of bromochloromethane in Synthesis Example 1. 5.5 g (yield 100%) of a reddish-brown transparent liquid was obtained as the product. The resulting compound had 1 1H-NMR (400 MHz, CDCl3) δ: 3.67 (t, 2H), 3.89 (t, 2H), 7.30 (m, 1H), 7.40 (m, 1H), 7.70 (m, 1H), 7.86 (m, 1H). These results supported the target structure.

[0036] [Chemical formula]

[0037] Synthesis of 2-acryloxyethylthiobenzothiazole (Compound 4) The procedure was the same as in Synthesis Example 2, except that the compound in Synthesis Example 2 was changed. As a result of the synthesis, 4.2 g (yield 91%) of a reddish-brown transparent liquid was obtained as the product. 1 1H-NMR (400 MHz, CDCl3) δ: 3.67 (t, 2H), 4.55 (t, 2H), 5.84 (dd, 1H), 6.10 (dd, 1H), 6.45 (dd, 1H), 7.30 (m, 1H), 7.40 (m, 1H), 7.70 (m, 1H), 7.86 (m, 1H). These results supported the target structure.

[0038]

Chem.

[0039] Example 1 Synthesis of 3-chloropropylthiobenzothiazole (Compound 5) The procedure was the same as in Synthesis Example 1, except that 1-chloro-3-bromopropane was used instead of bromochloromethane in Synthesis Example 1. A 5.8 g (yield 100%) of a reddish-brown transparent liquid was obtained as the product. The resulting compound had 1 1H-NMR (400 MHz, CDCl3) δ: 2.34 (m, 2H), 3.52 (t, 2H), 3.72 (t, 2H), 7.30 (m, 1H), 7.40 (m, 1H), 7.70 (m, 1H), 7.86 (m, 1H). These results supported the target structure.

[0040]

Chem.

[0041] Synthesis of 3-acryloxypropylthiobenzothiazole (Compound 6) The procedure was the same as in Synthesis Example 2, except that Compound 5 was used instead of Compound 1 in Synthesis Example 2. As a result of the synthesis, a 3.9 g (yield 85%) of a reddish-brown transparent liquid was obtained as the product. The resulting compound had 1 1H-NMR (400 MHz, CDCl3) δ: 2.25 (m, 2H), 3.67 (t, 2H), 4.33 (t, 2H), 5.84 (dd, 1H), 6.10 (dd, 1H), 6.45 (dd, 1H), 7.30 (m, 1H), 7.40 (m, 1H), 7.70 (m, 1H), 7.86 (m, 1H). These results supported the target structure.

[0042]

Chem.

[0043] Example 2 Synthesis of 4-chlorobutylthiobenzothiazole (Compound 7) The procedure of Synthesis Example 1 was repeated, except that 1-chloro-4-bromobutane was used instead of bromochloromethane. A 6.2 g (100% yield) of a reddish-brown transparent liquid product was obtained. The resulting compound was 1 1H-NMR (400 MHz, CDCl3) δ: 1.98 (m, 4H), 3.37 (t, 2H), 3.55 (t, 2H), 7.27 (m, 1H), 7.39 (m, 1H), 7.72 (m, 1H), 7.85 (m, 1H). These results supported the target structure.

[0044]

Chemical Structure

[0045] Synthesis of 4-acryloxybutylthiobenzothiazole (Compound 8) The procedure of Synthesis Example 2 was repeated, except that Compound 7 was used instead of Compound 1. A 6.0 g (85% yield) of a reddish-brown transparent liquid product was obtained. The resulting compound was 1 1H-NMR (400 MHz, CDCl3) δ: 1.98 (m, 4H), 3.40 (t, 2H), 4.22 (t, 2H), 5.84 (dd, 1H), 6.10 (dd, 1H), 6.45 (dd, 1H), 7.27 (m, 1H), 7.40 (m, 1H), 7.74 (m, 1H), 7.85 (m, 1H). These results supported the target structure.

[0046]

Chemical Structure

[0047] Example 3 Synthesis of 6-chlorobutylthiobenzothiazole (Compound 9) The procedure of Synthesis Example 1 was repeated, except that 1-bromo-6-chlorohexane was used instead of bromochloromethane. A 5.1 g (100% yield) of a yellow transparent liquid product was obtained. The resulting compound was 11H-NMR (400 MHz, CDCl3) δ: 1.51 (m, 4H), 1.83 (m, 4H), 3.37 (t, 2H), 3.55 (t, 2H), 7.27 (m, 1H), 7.39 (m, 1H), 7.72 (m, 1H), 7.85 (m, 1H). These were the results that supported the target structure.

[0048] [Chemical formula]

[0049] Synthesis of 6-methacryloxyhexylthiobenzothiazole (Compound 10) The compound 1 in Synthesis Example 2 was reacted with Compound 7 in the same manner as in Synthesis Example 2, except that potassium acrylate was changed to potassium methacrylate. As a result of the synthesis, 4.5 g (yield 95%) of a yellow transparent liquid was obtained as the product. The obtained compound had 1 1H-NMR (400 MHz, CDCl3) δ: 1.51 (m, 4H), 1.70 (m, 2H), 1.90 (m, 2H), 1.94 (s, 3H), 3.52 (t, 2H), 4.14 (t, 2H), 5.54 (s, 1H), 6.10 (s, 1H), 7.27 (m, 1H), 7.40 (m, 1H), 7.74 (m, 1H), 7.85 (m, 1H). These were the results that supported the target structure.

[0050] [Chemical formula]

[0051] For the compounds obtained in the Examples and Comparative Examples, the refractive index, odor, and physical properties were compared for each item. The refractive index was calculated by using the computer software ACD / ChemSketch 2012 (Advanced Chemistry Development, Inc.).

[0052] For the odor, sensory evaluation was performed by panelists. The evaluation criteria for the odor are as follows. ○: No odor △: Slight sulfur odor ×: With sulfur odor The physical properties were visually confirmed to be liquid or solid. The results are shown in the following table.

[0053]

Table 1

[0054] For Examples 1 to 3, compared with Comparative Examples 1 and 2 groups, the proportion of sulfur atoms in the molecular weight may be low, and almost no odor was felt. Also, in terms of physical properties, for Comparative Examples 1 and 2 groups, some solid precipitation was observed during storage at room temperature. Thus, by increasing the molecular weight of the whole compound, improvements in both odor and physical properties were observed. In terms of refractive index, Comparative Examples 1 and 2 groups showed higher values, but since Examples 1 to 3 groups also showed values of 1.60 or more, it was judged that they can be effectively used as high refractive index monomers from the comprehensive aspects such as odor and physical properties.

[0055] (Confirmation of Polymer Synthesis and Metal Adhesion Improvement Effect) Using the compounds obtained in the examples, polymer synthesis was carried out by a general solution polymerization method with the composition shown below. The obtained polymer solution was applied onto an aluminum substrate and dried to form a coating film. Regarding the metal adhesion improvement effect of such a coating film, the adhesion was confirmed by a cross-cut 1 mm grid test according to the method described in JIS K5600-5-6. The evaluation was conducted by the cross-cut test. The evaluation criteria for the cross-cut were as follows. 〇: No peeling △: Some peeling was observed. ×: The entire surface peeled off.

[0056]

Table 2

[0057] As shown in the results of the above table, a metal adhesion-imparting effect is clearly observed in the polymer containing Example 2 (Compound 8) in the composition, suggesting that the effect due to the structure of the compound is expressed.

Industrial Applicability

[0058] The sulfur atom-containing (meth)acrylate ester of the present invention can be used as a component such as a polymer raw material or an energy ray-curable resin composition, and more specifically, can be suitably used in the optical field, optical members, etc.

Claims

1. A sulfur atom-containing (meth)acrylic acid ester characterized by being represented by the following general formula (1). 【Chemical Formula 1】 (In the formula, n is 3 to 6. R ２ represents hydrogen or a methyl group)

2. A polymer having at least a part of the constituent units as the sulfur atom-containing (meth)acrylic acid ester of Claim 1.

Images