A raw material composition for producing a modified acrylic optical material

Abstract

The application discloses a raw material composition for preparing modified acrylic optical material, and belongs to the technical field of optical material preparation. The raw material composition comprises 1,3-bis (phenylthio) -2-propyl acrylate and acrylate monomer. The structure of the 1,3-bis (phenylthio) -2-propyl acrylate compound is shown as formula I, the compound contains two sulfur atoms and a benzene ring structure, has a high refractive index, and the product prepared by the preparation method has high purity. The modified acrylic optical material prepared by the raw material composition has high transmittance and refractive index.

Description

Technical Field

[0001] This invention belongs to the field of optical material preparation technology, specifically relating to a raw material composition for preparing modified acrylic optical materials. Background Technology

[0002] Acrylic optical materials are made from acrylate monomers through polymerization reactions. Common types include polymethyl methacrylate (PMMA) and polyacrylate. These materials have high light transmittance and are widely used in lenses, screens, optical fibers, and other fields. Acrylic optical materials typically have a light transmittance of over 90%, approaching that of glass but with a lower density, making them suitable for manufacturing lightweight products.

[0003] Existing acrylate optical monomers generally suffer from the following defects: ① Low refractive index: the n-value is typically 1.45-1.59, which is insufficient to meet the requirements of high-end optical design; ② Inadequate optical performance: the Abbe number is not ideal, making dispersion control difficult; ③ Poor weather resistance: long-term use easily leads to yellowing and deterioration of optical performance. Precision optical components have extremely strict requirements for the purity of acrylate materials, needing to reach above 99.5% to avoid optical defects and scattering losses. However, products prepared by traditional synthesis processes are difficult to meet the requirements of high-precision optical applications in terms of transmittance, refractive index uniformity, and colorimetric stability.

[0004] High-refractive-index and high-transmittance modified acrylates possess the advantages of "high performance + manufacturability" in future polymer optical materials. Through structural optimization such as heterocyclic / benzene ring / sulfur, they can undergo cross-linking polymerization with various monomers such as thiols and isocyanates, adapting to curing processes, shortening process cycles, reducing energy consumption and VOCs, and satisfying high optical and mechanical properties while maintaining low dispersion. In the future, they will have important application value in fields such as high-refractive-index optical lenses, optical systems, electronic display devices, and precision optical lenses, and are one of the key materials for achieving high transparency, lightweight, and precision in high-performance optical components.

[0005] There is an urgent need to develop raw materials for preparing modified acrylic optical materials with high refractive index and high transmittance, as well as efficient, environmentally friendly, and economical preparation technologies and processes to meet the upgrading needs of the optical materials industry. Summary of the Invention

[0006] To address the aforementioned problems in the prior art, this invention provides a raw material composition for modified acrylic optical materials, comprising 1,3-bis(phenylthio)-2-propyl acrylate and acrylate monomers. The 1,3-bis(phenylthio)-2-propyl acrylate compound, with the structure shown in Formula I, contains two sulfur atoms and a benzene ring structure, exhibiting a high refractive index. It is prepared using a stepwise one-pot feeding method, resulting in high product purity. The modified acrylic optical material obtained by polymerization of this composition exhibits high transmittance and refractive index.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A raw material composition for preparing modified acrylic optical materials, comprising 1,3-bis(phenylthio)-2-propyl acrylate (Formula I) and acrylate monomers;

[0009] .

[0010] In the raw material composition described above, preferably, the acrylate monomer is selected from at least one of hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl methacrylate, hydroxypropyl acrylate, hydroxybutyl methacrylate, 2-hydroxypropyl acrylate, hydroxybutyl acrylate, 2,3-dihydroxypropyl acrylate, trimethylolpropane trimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, trimethylolpropane monoallyl acrylate, ethylene glycol dimethacrylate, bisphenol A diacrylate, and dimethacrylate-1,12-dodecyl diacrylate.

[0011] In the raw material composition described above, preferably, the weight ratio of 1,3-bis(phenylthio)-2-propyl acrylate to acrylate monomer is 1:(1~1.3).

[0012] The raw material composition described above, preferably, is prepared by the following method, the chemical reaction process of which is as follows:

[0013] First stage: Disulfide reaction. The hydroxyl group of glycerol is activated under the action of a catalyst to form a positive ion. The thiophenol sulfide ion attacks the 1,3-hydroxyl group of glycerol, resulting in a di-substitution reaction, forming a CS bond, and generating the 1,3-bis(phenylthio)-2-propanol intermediate.

[0014] The second stage is the esterification reaction. The hydroxyl group of 1,3-bis(phenylthio)-2-propanol undergoes nucleophilic attack on the carbonyl carbonyl group of acryloyl chloride to form an intermediate. The chloride ion leaves, and triethylamine abstracts a proton to complete the esterification, generating the target product 1,3-bis(phenylthio)-2-propoacrylate.

[0015] .

[0016] Specifically, the preparation method includes the following steps:

[0017] Glycerol and an acid catalyst were added to a reaction vessel containing solvent with stirring. N2 was continuously introduced and the temperature was controlled at 55-80°C. Thiophenol was added dropwise, and the reaction was carried out for 2-4 hours. The mixture was cooled to 0-10°C, and an alkaline hydrolysant was added in batches with stirring. Acryloyl chloride was added dropwise, and the temperature was raised to room temperature. The reaction was continued for 2-3 hours. The mixture was neutralized to pH 6-7 with an alkaline solution. The organic phase was separated and eluted. The solvent and catalyst were collected by vacuum distillation to obtain 1,3-bis(phenylthio)-2-propyl acrylate (I).

[0018] In the raw material composition described above, preferably, the weight ratio of glycerol, acryloyl chloride, thiophenol and solvent is (1~1.2):(1~1.2):(2~3):(2~4).

[0019] In the above-described raw material composition, preferably, the acid catalyst is a boron trifluoride diethyl ether complex.

[0020] In the above-described raw material composition, preferably, the amount of catalyst used is 3 to 7 wt% of the amount of glycerol.

[0021] In the raw material composition described above, preferably, the solvent is selected from at least one of toluene, butanol, xylene, isobutanol, butyl acetate, isobutyl acetate, and sec-butyl acetate.

[0022] In the raw material composition described above, preferably, the alkaline hydrolysant is selected from at least one of trimethylamine, triethylamine, and diethylamine.

[0023] In the raw material composition described above, preferably, the amount of alkaline hydrolysant is 40-100 wt% of the amount of acryloyl chloride.

[0024] On the other hand, the present invention provides a modified acrylic optical material, which is polymerized from 1,3-bis(phenylthio)-2-propyl acrylate (Formula I) and acrylate monomers.

[0025] The beneficial effects of this invention are as follows:

[0026] The raw material composition of the modified acrylic optical material of the present invention consists of 1,3-bis(phenylthio)-2-propyl acrylate and acrylate monomers. 1,3-bis(phenylthio)-2-propyl acrylate has a high refractive index and transmittance, and its preparation method produces high-purity products. It can be used as a monomer in the composition of modified acrylic optical materials to improve the optical performance of optical materials.

[0027] The modified acrylic optical material made from the raw material composition of the present invention has high transmittance and refractive index. Attached Figure Description

[0028] Figure 1The FT-IR infrared spectrum of 1,3-bis(phenylthio)-2-propyl acrylate prepared in Example 1.

[0029] Figure 2 The image shows the 1H NMR spectrum of 1,3-bis(phenylthio)-2-propyl acrylate prepared in Example 1. Detailed Implementation

[0030] The present invention will be further described below through specific embodiments, but this does not imply a limitation on the scope of protection of the present invention.

[0031] Example 1 Preparation of 1,3-bis(phenylthio)-2-propyl acrylate

[0032] 180 g of glycerol and 10 g of BF3•Et2O were added to a reaction vessel containing 500 g of isobutanol solvent with stirring. N2 was continuously introduced, and the temperature was maintained at 75 °C. 440 g of thiophenol was added dropwise, and the reaction proceeded for 3.5 h. The mixture was then cooled to 5 °C, and 50 g of triethylamine was added with stirring. 180 g of acryloyl chloride was added dropwise over 2 h. The temperature was raised to room temperature, and the reaction proceeded for 1 h. 55 g of triethylamine was then added, and the reaction proceeded for 2 h. The mixture was neutralized to pH 6.5 with an aqueous sodium bicarbonate solution. The organic phase was separated and eluted. The solvent and catalyst were collected by vacuum distillation to yield 443.5 g of 1,3-bis(phenylthio)-2-propyl acrylate (I). The yield was 66.0%.

[0033] Purity Testing and Analysis: The purity of the product prepared in Example 1 was tested using high-performance liquid chromatography (HPLC). Testing Procedure and Method: 20 mg of 1,3-bis(phenylthio)-2-propylacrylate was accurately weighed into an 8 mL acetonitrile volumetric flask and sonicated for 6 minutes to ensure complete dissolution. A C18 column was selected, and the mobile phase was an acetonitrile-water gradient elution. Since 1,3-bis(phenylthio)-2-propylacrylate contains a benzene ring and has a certain degree of hydrophobicity, the C18 column exhibits good π-π interactions with the benzene ring, allowing different impurities to be separated due to differences in hydrophobicity. Detection wavelength: 254 nm or 280 nm (UV absorption of the benzene ring). Purity (%) = (target peak area / total peak area) × 100%. The product purity was calculated to be 99.7% based on the peak area.

[0034] Fourier Transform Infrared (FT-IR) Spectroscopy Test: The product prepared in Example 1 was subjected to Fourier Transform Infrared (FT-IR) spectroscopy test, such as... Figure 1 As shown in the figure, the curve analysis shows that 3025-3100 cm -1 The absorption peak at 2850-2980 cm⁻¹ corresponds to the CH stretching vibration of aromatic and olefinic compounds. -1 The absorption peaks at 1720-1735 cm⁻¹ are due to the stretching vibrations of the -CH- and -CH₂- groups. -1The absorption peak at 1620-1638 cm⁻¹ is due to the stretching vibration of the carbonyl group (C=O) in esters (strong peak). -1 The absorption peak at 1480-1500 cm⁻¹ is due to the C=C stretching vibration (characteristic peak of the propenyl double bond). -1 and 1580-1600cm -1 The location is a benzene ring skeletal vibration, 1410-1420 cm. -1 The absorption peak at 1120-1185 cm⁻¹ is due to the in-plane bending vibration of =CH. -1 The absorption peak at 960-990 cm⁻¹ corresponds to the stretching vibration of the ester group (CO). -1 The absorption peak at 810-840 cm⁻¹ corresponds to the out-of-plane bending vibration of CH (propenyl group). -1 The absorption peak is due to the out-of-plane bending vibration of =CH2 (propene group terminus), 690-750 cm⁻¹ -1 The absorption peaks are due to the out-of-plane bending vibrations of monosubstituted CH groups on the benzene ring, 630-692 cm⁻¹. -1 The absorption peak at that point is due to the CS stretching vibration, which is a characteristic peak of the thioether bond.

[0035] 1H NMR spectrum analysis: δ = 7.40~7.22 ppm (m, 10H, 2×C6H5), 6.45~6.35 ppm (dd, 1H, =CH- olefin protons connected to the ester group), 6.20~6.15 ppm (dd, 1H, CH2= two hydrogens are not equivalent, one of the trans hydrogens at the end of the propenyl group), 6.00-5.95 ppm (dd, 1H, =CH2, the other cis hydrogen at the end of the propenyl group), 5.35~5.20 ppm (m, 1H, ester-linked methylene-CH-), 3.42~3.12 ppm (d, 4H, 2× methylene protons of the -CH2S- group).

[0036] Example 2: Preparation of 1,3-bis(phenylthio)-2-propyl acrylate

[0037] 120 g of glycerol and 8 g of BF3•Et2O were added to a reaction vessel containing 350 g of isobutanol solvent with stirring. N2 was continuously introduced, and the temperature was maintained at 75 °C. 295 g of thiophenol was added dropwise, and the reaction proceeded for 3.2 h. The mixture was then cooled to 3 °C, and 40 g of triethylamine was added with stirring. 118 g of acryloyl chloride was added dropwise over 2 h. The temperature was raised to room temperature, and the reaction proceeded for 1 h. 45 g of triethylamine was then added, and the reaction proceeded for another 2 h. The mixture was neutralized to pH 6.3 with an aqueous sodium bicarbonate solution. The organic phase was separated and eluted. The solvent and catalyst were collected by vacuum distillation to yield 299.4 g of 1,3-bis(phenylthio)-2-propyl acrylate (I). The yield was 66.6%.

[0038] The 1,3-bis(phenylthio)-2-propyl acrylate prepared in Example 2 was subjected to FT-IR and 1H NMR nuclear magnetic resonance spectroscopy. The test results were basically the same as those in Example 1.

[0039] Example 3: Preparation of 1,3-bis(phenylthio)-2-propyl acrylate

[0040] 160 g of glycerol and 9 g of BF3•Et2O were added to a reaction vessel containing 450 g of isobutanol solvent with stirring. N2 was continuously introduced, and the temperature was maintained at 75 °C. 395 g of thiophenol was added dropwise, and the reaction proceeded for 3.5 h. The mixture was then cooled to 5 °C, and 50 g of triethylamine was added with stirring. 155 g of acryloyl chloride was added dropwise over 2 h. The temperature was raised to room temperature, and the reaction proceeded for 1 h. Another 50 g of triethylamine was added, and the reaction proceeded for 2 h. The mixture was neutralized to pH 6.6 with an aqueous sodium bicarbonate solution. The organic phase was separated and eluted. The solvent and catalyst were collected by vacuum distillation to yield 400.6 g of 1,3-bis(phenylthio)-2-propyl acrylate (I). The yield was 67.9%.

[0041] Example 4: Preparation of 1,3-bis(phenylthio)-2-propyl acrylate

[0042] 80 g of glycerol and 5 g of BF3•Et2O were added to a reaction vessel containing 220 g of isobutanol solvent with stirring. N2 was continuously introduced, and the temperature was maintained at 75 °C. 200 g of thiophenol was added dropwise, and the reaction proceeded for 3 h. The mixture was then cooled to 5 °C, and 40 g of triethylamine was added with stirring. 90 g of acryloyl chloride was added dropwise over 2 h. The temperature was raised to room temperature, and the reaction proceeded for 1 h. 50 g of triethylamine was then added, and the reaction proceeded for 2 h. The mixture was neutralized to pH 6.5 with an aqueous sodium bicarbonate solution. The organic phase was separated and eluted. The solvent and catalyst were collected by vacuum distillation to yield 200.2 g of 1,3-bis(phenylthio)-2-propyl acrylate (I). The yield was 67.1%.

[0043] Example 5: Preparation of 1,3-bis(phenylthio)-2-propyl acrylate

[0044] 140 g of glycerol and 8 g of BF3•Et2O were added to a reaction vessel containing 400 g of isobutanol solvent with stirring. N2 was continuously introduced, and the temperature was maintained at 75 °C. 350 g of thiophenol was added dropwise, and the reaction proceeded for 3.5 h. The mixture was then cooled to 5 °C, and 60 g of triethylamine was added with stirring. 140 g of acryloyl chloride was added dropwise over 2 h. The mixture was heated to room temperature and reacted for 1 h. 50 g of triethylamine was then added, and the reaction proceeded for 2 h. The mixture was neutralized to pH 6.4 with an aqueous sodium bicarbonate solution. The organic phase was separated and eluted. The solvent and catalyst were collected by vacuum distillation to yield 352.2 g of 1,3-bis(phenylthio)-2-propyl acrylate (I). The yield was 67.4%.

[0045] Example 6: Preparation of Modified Acrylic Optical Materials

[0046] 55g of 1,3-bis(phenylthio)-2-propyl acrylate prepared in Example 1 and 65g of bisphenol A diacrylate (Ao Ke New Material Technology (Shanghai) Co., Ltd., model AR-573) were added to a reaction vessel. 0.06g of 2,6-di-tert-butyl-p-cresol and 0.18g of azobisisobutyronitrile were added and stirred at room temperature for 25min. The mixture was then evacuated for 20min using a vacuum pump. The air-removed mixture was pressurized with nitrogen and filtered through a 0.45µm capsule filter. The mixture was then poured into a tempered mold. The tempered mold containing the prepolymer was placed in a curing oven and cured at 35℃ for 2.5h, 50℃ for 3h, 70℃ for 3h, and 85℃ for 2h. Annealing was then carried out at 65℃ for 1h. The mold was then cooled to room temperature, demolded, and sampled to obtain the modified acrylic optical material.

[0047] Comparative Example 1: Preparation of Conventional Acrylic Optical Materials

[0048] The same preparation method as in Example 6 was used, except that 1,3-bis(phenylthio)-2-propyl acrylate was replaced with hydroxyethyl methacrylate. The specific operation method is as follows:

[0049] 55g of hydroxyethyl methacrylate and 65g of bisphenol A diacrylate (Ao Ke New Material Technology (Shanghai) Co., Ltd., model AR-573) were added to a reaction vessel. 0.06g of 2,6-di-tert-butyl-p-cresol and 0.18g of azobisisobutyronitrile were added and stirred at room temperature for 25 minutes. The mixture was then evacuated for 20 minutes using a vacuum pump. The air-removed mixture was pressurized with nitrogen and filtered through a 0.45µm capsule filter. The mixture was then poured into a tempered mold. The tempered mold containing the prepolymer was placed in a curing oven and cured at 35℃ for 2.5 hours, then at 50℃ for 3 hours, then at 70℃ for 3 hours, then at 85℃ for 2 hours. The mixture was then annealed at 65℃ for 1 hour, cooled to room temperature, demolded, and sampled to obtain acrylic optical material.

[0050] Example 7: Optical performance testing experiment of modified optical materials

[0051] The optical properties of the products prepared in Examples 1-6 and Comparative Example 1 were tested. Transmittance was measured using a Lambda 650S UV-Vis spectrophotometer (PerkinElmer Chemical Analysis Instruments, Inc.), and refractive index was measured using an Rx-7000 digital refractometer (Shanghai Optical Instrument Equipment Co., Ltd.). The testing method involved directly coating or placing the prepared sample onto the prism of the UV-Vis spectrophotometer or the prism of the refractometer. The yellow index was calculated from the spectrophotometer reading using the formula: YI = 100(1.28X - 1.06Z) ÷ Y, where X, Y, and Z are the tristimulus values ​​of the C light source. The test results are shown in Table 1.

[0052] .

[0053] The test results show that the 1,3-bis(phenylthio)-2-propyl acrylate created in this invention has excellent optical properties, and the acrylic optical materials prepared from it have high transmittance and refractive index.

Claims

1. A method for preparing a raw material composition for preparing modified acrylic optical materials, characterized in that, The raw material composition includes 1,3-bis(phenylthio)-2-propyl acrylate (Formula I) and acrylate monomers; （I） 1,3-bis(phenylthio)-2-propyl acrylate was prepared by the following method: Glycerol and an acid catalyst were added to a reaction vessel containing solvent with stirring. N2 was continuously introduced and the temperature was controlled at 55-80°C. Thiophenol was added dropwise, and the reaction was carried out for 2-4 hours. The mixture was cooled to 0-10°C, and an alkaline hydrolysant was added in batches with stirring. Acryloyl chloride was added dropwise, and the temperature was raised to room temperature. The reaction was continued for 2-3 hours. The mixture was neutralized to pH 6-7 with an alkaline solution. The organic phase was separated and eluted. The solvent and catalyst were collected by vacuum distillation to obtain 1,3-bis(phenylthio)-2-propyl acrylate (I). The weight ratio of glycerol, acryloyl chloride, thiophenol and solvent is (1~1.2):(1~1.2):(2~3):(2~4); The acid catalyst is a boron trifluoride diethyl ether complex, and the amount of acid catalyst used is 3-7 wt% of the amount of glycerol. The solvent is selected from at least one of toluene, butanol, xylene, isobutanol, butyl acetate, isobutyl acetate, and sec-butyl acetate.

2. The preparation method according to claim 1, characterized in that, The acrylate monomer is selected from at least one of hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl methacrylate, hydroxypropyl acrylate, hydroxybutyl methacrylate, 2-hydroxypropyl acrylate, hydroxybutyl acrylate, 2,3-dihydroxypropyl acrylate, trimethylolpropane trimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, trimethylpropane monoallyl acrylate, ethylene glycol dimethacrylate, bisphenol A diacrylate, and dimethacrylate-1,12-dodecyl diacrylate.

3. The preparation method according to claim 1, characterized in that, The alkaline hydrolysant is selected from at least one of trimethylamine, triethylamine, and diethylamine.

4. The preparation method according to claim 1, characterized in that, The amount of alkaline hydrolysant used is 40-100 wt% of the amount of acryloyl chloride used.

5. The preparation method according to any one of claims 1-4, characterized in that, The weight ratio of 1,3-bis(phenylthio)-2-propyl acrylate to acrylate monomer is 1:(1~1.3).

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