A sulfur-containing high-refractive photocurable monomer

Abstract

The present invention discloses a sulfur-containing high-refractive photocurable monomer having a chemical structure of the following formula (I) or formula (II): Formula (I) Formula (II) X1 represents a polymerizable group, and X2 is a group with high refractive properties. The structure of the present invention contains a five-membered heterocyclic ring with two sulfur atoms. Compared with the reported thiophenes, thiadiazoles and cyclic trithiocarbonates, the structure has the characteristics of novel structure, colorlessness and high refractive index.

Description

Technical Field

[0001] The invention relates to the field of curing monomers, in particular to a sulfur-containing high-refractive light-curing monomer. Background Art

[0002] Compared with other high-refractive materials, sulfur-containing high-refractive materials have the advantages of high molar refractive index, high Abbe coefficient, good light transmittance and good mechanical properties, and have become a hot spot in the field of high-refractive material research in recent years. At present, the structures of sulfur-containing high refractive materials include fatty alkyl sulfides and aromatic sulfides. Compared with fatty alkyl sulfides, cyclic sulfur-containing monomers have the advantages of better refractive index and better heat resistance. The aromatic sulfide structures mainly include diphenyl sulfide, thiadiazole and cyclic trithiocarbonate. The diphenyl sulfide structure is relatively simple and is generally used for condensation polymers, such as a series of polyimide diphenyl sulfide polymer materials mentioned in the literature Macromolecules 2015, 48, 1915–1929. This type of structure generally needs to be made into a solution or heated and melted before use, which cannot meet the requirements of photocuring. The literature J Polym Sci. 2020; 1–8 reported a methacrylate monomer containing cyclic thiocarbonate (TCMA). Although the refractive index of the monomer is 1.63, it is orange-yellow and cannot be used as an optical film. In addition, as an active structure, cyclic thiocarbonate has the hidden danger of unstable properties when used as a material. Therefore, it is very meaningful to develop new sulfur-containing heterocyclic structures and use them in photopolymerizable monomers. Summary of the invention

[0003] The purpose of the present invention is to provide a sulfur-containing high-refractive photocurable monomer.

[0004] The innovation of the present invention is that the structure of the present invention contains a five-membered heterocyclic ring with two sulfur atoms. Compared with the reported thiophenes, thiadiazoles and cyclic trithiocarbonates, the structure has the characteristics of novel structure, colorlessness and high refractive index.

[0005] In order to achieve the above-mentioned object of the invention, the technical solution of the present invention is:

[0006] A sulfur-containing high-refractive photocurable monomer, characterized in that it has a chemical structure of the following formula (I) or formula (II):

[0007]

[0008] X1 represents a polymerizable group, and X2 is a group having a high refractive property.

[0009] Furthermore, X1 is a structure containing acrylate or methacrylate.

[0010] Furthermore, formula (I) comprises

[0011]

[0012]

[0013] Further, formula (II) comprises

[0014]

[0015] The beneficial effects of the present invention are:

[0016] Furthermore, the compound (I) or (II) is used as a high-refractive monomer in the field of photocuring.

[0017] 1. The core structure of the present invention is one or two five-membered heterocyclic rings containing two sulfurs, and the five-membered heterocyclic rings are connected to X2 through enamine, wherein X1 represents a polymerizable group, generally containing acrylate or methacrylate, which can be connected to the five-membered sulfur-containing core structure through a methylene group, or can be a six-membered ring containing a five-membered sulfur-containing heterocyclic ring in a ring structure, and then connected to acrylate or methacrylate. X2 is a common group with high refractive properties. X1 and X2 are connected through a five-membered sulfur-containing heterocyclic ring.

[0018] 2. The structure of the present invention contains a five-membered heterocyclic ring with two sulfur atoms. Compared with the reported thiophenes, thiadiazoles and cyclic trithiocarbonates, the structure has the characteristics of novel structure, colorlessness and high refractive index. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention will be described clearly and completely below.

[0020] Embodiment 1: A sulfur-containing high-refractive photocurable monomer having a chemical structure of the following formula (I) or formula (II):

[0021]

[0022] X1 represents a polymerizable group, and X2 is a group having a high refractive property.

[0023] X1 is a structure containing acrylate or methacrylate.

[0024] Formula (I) comprises

[0025]

[0026]

[0027] Formula (II) includes

[0028]

[0029]

[0030] The compound (I) or (II) is used as a high-refractive monomer in the field of photocuring.

[0031] Example 2: Monomer 1 is

[0032] The synthesis method of monomer 1 is as follows:

[0033]

[0034] (1) The synthesis process of compound 1-ii is as follows:

[0035] The raw material 1-i (74.08g, 1mol) and triethylamine (106.05g, 1.05mol) were dissolved in dichloromethane (500mL) to form a reaction solution No. 1. TBSCl (150.7g, 1mol) was slowly added dropwise to the reaction solution No. 1 under an ice bath. After the addition, the reaction solution was warmed to room temperature and continued to stir for 16h. After the reaction was completed, the reaction solution No. 1 was quenched into a saturated aqueous solution of ammonium chloride, and the liquid was separated to obtain an organic phase No. 1. The organic phase No. 1 was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to obtain the product 1-ii (188g), which was directly used in the next step reaction.

[0036] (2) The crude compound 1-ii (188 g, about 1 mol) was dissolved in ethanol (1 L), and potassium thiocyanate (194.5 g, 2 mol) was slowly added at room temperature. After the addition was completed, stirring was continued for 16 h to obtain reaction solution No. 2. The reaction solution No. 2 was quenched into saturated brine and extracted three times with petroleum ether to obtain organic phase No. 2. The organic phase No. 2 was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to obtain crude product 1-iii (190 g, crude product) which was directly used in the next step reaction.

[0037] (3) Compound 1-iii (190 g, crude product, about 0.93 mol) and triethylamine (0.94 g, 9.3 mmol) were uniformly mixed, and carbon disulfide (153 g, 2 mol) was slowly added dropwise at 20°C to obtain reaction solution No. 3. After the addition, stirring was continued for 16 hours. After the reaction was completed, reaction solution No. 3 was quenched into saturated aqueous ammonium chloride solution, and organic phase No. 3 was extracted with ethyl acetate. Organic phase No. 3 was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The crude product was separated by column chromatography to obtain compound 1-iv (194 g, three-step combined yield 69%).

[0038] (4) Under nitrogen atmosphere, compound 1-v (194 g, 0.69 mol), aniline (65.2 g, 0.7 mol) and 1-butyl-3-methylimidazolium acetate (13.9 g, 0.07 mol) were uniformly mixed and reacted at 140° C. for 10 hours to obtain reaction solution No. 4. After the reaction, reaction solution No. 4 was quenched into saturated aqueous ammonium chloride solution, and organic phase No. 4 was extracted with ethyl acetate. The organic phase No. 4 was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The crude product was separated by column chromatography to obtain compound 1-v (114.8 g, yield 49%).

[0039] (5) Compound 1-v (114.8 g, 0.338 mol) was dissolved in THF (500 mL), and TBAF (1 M, 350 mL, 0.35 mol) was slowly added to the reaction solution under ice bath to obtain reaction solution No. 5. The reaction solution was slowly heated to room temperature and stirred for 16 h. After the reaction was completed, reaction solution No. 5 was concentrated, and the crude product was separated by column chromatography to obtain product 1-vi (72 g, yield 94.5%).

[0040] (6) Compound 1-vi (72 g, 0.32 mol) and triethylamine (35.5 g, 0.35 mol) were dissolved in dichloromethane (1 L), and methacryloyl chloride (35.5 g, 0.34 mol) was slowly added to the reaction solution under ice bath to obtain reaction solution No. 6, and the reaction solution was slowly heated to room temperature and stirred for 16 h. After the reaction was completed, reaction solution No. 6 was quenched into saturated aqueous ammonium chloride solution, extracted with ethyl acetate to obtain organic phase No. 6, washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The crude product was separated by column chromatography to obtain monomer product 1 (75.1 g, 80%), with a refractive index of 1.618.

[0041] The chemical structure of monomer 1 was tested, and the NMR characterization results are as follows:

[0042] 1 H NMR(400MHz, CDCl3)δ:7.32–7.28(t,J=8Hz,2H),7.11–7.07(t,J=8Hz,1H),6.93–6.90(m,2H), 6.12(s,1H),5.60(s,1H),4.41–4.21(m,2H),4.12–4.08(m,1H),3.67–3.39(m,2H),1.92(s,3H)

[0043] Example 3: Referring to Example 2, methacryloyl chloride is replaced by acryloyl chloride to obtain a monomer

[0044] Example 4: Monomer 2

[0045] The synthetic route of monomer 2 is as follows:

[0046]

[0047] The refractive index of monomer 2 is 1.650, and the NMR characterization results are as follows:

[0048] 1 H NMR(400MHz, CDCl3)δ:7.51-7.47(m,2H),7.40–7.35(d,1H),7.19–7.14(t,1H),7.05–7.01(t,1H),6.75(s,1H), 6.72–6.70(d,1H),6.14(s,1H),5.62(s,1H),4.47–4.29(m,2H),4.20–4.17(d,2H),3.72–3.51(m,1H),2.0(s,3H)

[0049] Example 5: Referring to Example 4, methacryloyl chloride is replaced with acryloyl chloride to obtain a monomer

[0050]

[0051] Example 6: Synthesis of monomer 7, monomer 7 is

[0052]

[0053] The synthetic route of monomer 7 is as follows:

[0054]

[0055] (1) The synthesis process of compound 7-ii is as follows:

[0056] Compound 7-i (112.1 g, 1 mol) was dissolved in dichloromethane (1 L), and m-CPBA (190 g, 1.1 mol) was slowly added to the reaction solution at room temperature. After the addition was completed, the reaction solution No. 7 was stirred for 5 hours. After the reaction was completed, the reaction solution was quenched into a 10% sodium sulfite aqueous solution (1 L), stirred for 0.5 hours, and extracted with ethyl acetate three times to obtain an organic phase No. 7. The organic phases were combined, washed with a saturated sodium bicarbonate aqueous solution, dried over anhydrous sodium sulfate, filtered and concentrated to obtain a crude product 7-ii (120 g, about 0.93 mol) which was directly used in the next step.

[0057] (2) The synthesis process of compound 7-iii is the same as that of compound 1-ii

[0058] (3) The synthesis process of compound 7-iv is the same as that of compound 1-iii

[0059] (4) The synthesis process of compound 7-v is the same as that of compound 1-iv

[0060] (5) The synthesis process of compound 7-vi is the same as that of compound 1-v

[0061] (6) The synthesis process of compound 7-vii is the same as that of compound 1-vi

[0062] (7) The synthesis process of monomer 7 is the same as that of monomer 1. Its refractive index is 1.623. The NMR characterization results are as follows:

[0063] 1 H NMR(400MHz, CDCl3)δ:7.31–7.27(t,2H),7.10–7.06(t,1H),6.91-6.88(d,2H),6.08–6.05(d,1H),5.57–5.53(dd,1H),4.22– 4.17(m,2H),3.75–3.69(m,1H),3.59–3.52(m,1H),2.38–2.35(m,1H),2.26–2.01(m,2H),1.98–1.95(d,3H),1.91–1.78(m,4H)

[0064] Example 7: Synthesis of Monomer 5, Monomer 5 is

[0065]

[0066] The synthetic route of monomer 5 is as follows:

[0067]

[0068] The refractive index of monomer 5 is 1.645, and its NMR characterization is as follows:

[0069] 1 H NMR(400MHz, CDCl3)δ:7.55-7.49(m,4H),7.24-7.19(m,4H),6.14(s,2H),5.6 1(s,2H),4.41–4.21(m,4H),4.11–4.08(m,2H),3.45–3.39(m,4H),1.98(s,6H)

[0070] The refractive index and properties of some products in the present invention are as follows:

[0071]

[0072]

[0073]

[0074] Comparison of applications in optical films: Taking the existing commercially available product OPPEA (structure as shown in the table) as an example, light-initiated free radical polymerization is adopted. The specific operation is as follows: 2 parts by weight of photoinitiator (1173) and 100 parts by weight of OPPEA are evenly spread on a glass slide, and irradiated with a high-pressure mercury lamp (lamp distance 5 cm, light intensity I365 = 1mW / cm2) to obtain an OPPEA polymerized optical film. The refractive index of the film is measured to be 1.59, and the cured film is colorless.

[0075] Application of monomer 1 in optical film: Taking monomer 1 of the present invention as an example, light-initiated free radical polymerization is adopted, and the specific operation is as follows: 2 parts by weight of free radical photoinitiator (1173) is evenly mixed with 100 parts by weight of monomer 1, and then evenly applied on a glass slide. It is irradiated with a high-pressure mercury lamp (lamp distance 5 cm, light intensity I365 = 1 mW / cm2) to obtain an optical film containing free radical photopolymerization of monomer 1 in the present invention. The refractive index of the film is measured to be 1.629, and the cured film is colorless.

[0076] The described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Claims

1. A sulfur-containing high-refractive photocurable monomer, characterized in that: Selected from the following compounds 2. An application of the sulfur-containing high-refractive photocurable monomer as claimed in claim 1, characterized in that: The compound described in claim 1 is used as a high-refractive monomer in the field of photocuring.

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