Optical resin for microprism or microlens as well as preparation and application of optical resin

Abstract

The invention relates to the technical field of optical resin preparation, in particular to optical resin for a microprism or a microlens and preparation and application of the optical resin. The optical resin composition provided by the invention comprises the following components: 45-60 parts of an acrylate polymer, 15-25 parts of diisocyanate, 20-30 parts of a polythiol compound, 0.1-1 part of a catalyst, 0.5-1 part of a release agent and 0.1-0.5 part of an ultraviolet absorbent, the acrylate polymer is prepared by polymerizing acrylate monomers I-1 and II-1, and the ultraviolet absorbent is prepared by polymerizing acrylate monomers I-1 and II-1. The optical resin prepared from the optical resin composition has high refractive index and high light transmittance.

Description

Technical Field

[0001] This invention relates to the field of optical resin preparation technology, and in particular to an optical resin for microprisms or microlenses, and its preparation and application. Background Technology

[0002] Optical materials refer to functional materials used in optical experiments and instruments to achieve light transmission and control. Based on their structure, they can be mainly divided into two categories: inorganic optical glass and organic optical resins. Inorganic optical glass typically possesses excellent mechanical properties, such as high strength, high stiffness, and high hardness, while exhibiting advantages in optical properties such as high refractive index, low dispersion, good stability, and high transmittance. However, the difficulty in processing and molding these materials, along with their complex manufacturing processes, limits their widespread application.

[0003] In contrast, organic optical resins have significant advantages such as ease of processing and molding, good film-forming properties, impact resistance, lightweight and thin texture, and ease of coloring. Therefore, they are gradually replacing inorganic glass in fields such as optical lenses, building materials, optical lenses, and optical thin films, and have gained widespread use. However, due to their molecular structure characteristics, organic optical resins generally suffer from problems such as low hardness, poor heat resistance and solvent resistance, high coefficient of thermal expansion and water absorption, and low refractive index, which restrict their further expansion in advanced optics fields.

[0004] It is noteworthy that the structure and properties of organic materials are highly tunable; their hardness, heat resistance, solvent resistance, and water absorption can all be effectively controlled by introducing specific chemical groups. Currently, the main technical approaches to improving the refractive index of organic materials include introducing high-sulfur groups, aromatic ring structures, halogens (except fluorine), and incorporating high-refractive-index inorganic nanoparticles. Nevertheless, existing methods still face several key bottlenecks hindering their large-scale commercial application: (1) Most high refractive index optical resins require multiple complex reactions to prepare, and the synthesis process is complicated, resulting in low yield and high cost; (2) The introduction of a large number of aromatic ring structures can increase the refractive index, but it often damages the solubility and light transmittance of the material, thereby affecting the processing performance and optical quality; (3) Inorganic nanoparticles have poor dispersibility and compatibility in organic matrices, and are prone to agglomeration, which reduces the optical transmittance of composite materials. (4) Under the premise of maintaining high light transmittance, the amount of inorganic nanoparticles added is limited, making it difficult to prepare optical composite materials with ultra-high refractive index or suitable for thick bulk products.

[0005] Therefore, developing simple and efficient preparation methods to obtain optical resins with high refractive index and excellent comprehensive performance has become a key research direction to promote their large-scale commercial application. Summary of the Invention

[0006] In view of this, the present invention provides an optical resin for microprisms or microlenses, and its preparation and application.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solution: In a first aspect, the present invention provides an optical resin composition comprising (a) an acrylate polymer; (b) a diisocyanate; and (c) a polythiol compound. The acrylate polymer is obtained by free radical polymerization of acrylate monomer I-1 and acrylate monomer II-1. The molar ratio of acrylate monomer I-1 to acrylate monomer II-1 is 1:0.5-2; preferably, the molar ratio is 1:1. The structural formula of the acrylate monomer I-1 is: ; The structural formula of acrylate monomer II-2 is: .

[0008] Furthermore, the optical resin composition also includes additives such as catalysts, release agents, and ultraviolet absorbers.

[0009] Further, by mass fraction, the optical resin composition comprises the following components: 45-60 parts of acrylate polymer, 15-25 parts of diisocyanate, 20-30 parts of polythiol compound, 0.1-1 part of catalyst, 0.5-1 part of release agent, and 0.1-0.5 parts of ultraviolet absorber.

[0010] Further, the diisocyanate is at least one selected from phthalic diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, 4,4-dicyclohexylmethane diisocyanate, and hydrogenated phthalic diisocyanate.

[0011] Further, the polythiol compound is at least one of thiodiglycol, 2,3-dithio(2-mercapto)-1-propanethiol, tetra(mercaptomethyl)methane, pentaerythritol tetra(3-mercaptopropionic acid) ester, pentaerythritol tri(3-mercaptopropionic acid) ester, pentaerythritol tetra(3-mercaptobutyric acid) ester, and bis(mercaptomethyl)-3,6,9-trithiaundecane-1,11-dithiol.

[0012] Furthermore, the catalyst is triethylenediamine, hexamethylenetetramine, N,N-dimethyloctylamine, dibutyltin dichloride, or trimethyltin chloride.

[0013] Furthermore, the release agent includes at least one of di-n-butyl phosphate and nonylphenol polyoxyethylene ether phosphate.

[0014] Furthermore, the ultraviolet absorber is at least one of UV326, UV327, UV329, UV-531, UV-9, and UV-234.

[0015] In a second aspect, the present invention provides an optical resin prepared from the optical resin composition described in the first aspect.

[0016] Furthermore, the optical resin has a refractive index of 1.65-1.8 and a light transmittance greater than 94%.

[0017] Thirdly, the present invention provides a method for preparing the optical resin described in the second aspect, comprising the following steps: (1) Disperse the acrylate polymer in diisocyanate, stir to obtain a uniformly dispersed solution, then add catalyst, release agent and ultraviolet absorber to the solution, stir to obtain a uniformly dispersed solution; (2) Add polythiol compound to the solution obtained in step (1), stir to obtain a mixed solution; pour the mixed solution into a mold, heat it to polymerize it, and obtain an optical resin.

[0018] Furthermore, the polymerization temperature is 80-100℃; the time is 10-14h.

[0019] Furthermore, the acrylate polymer is prepared by thermosetting. The specific method is as follows: acrylate monomers I-1 and II-1 are added to an organic solvent, then an initiator is added, and the acrylate monomers and initiator are dissolved by sonication. After filtration, the polymer is then thermoset to obtain the final product.

[0020] Furthermore, the organic solvent is at least one of acetone and isopropanol.

[0021] Furthermore, the initiator is tert-amyl peroxide acetate or BPO, and the amount of initiator added is 0.05-0.2% of the total mass of acrylate monomers I-1 and II-1.

[0022] Furthermore, the ultrasound time is 5-20 minutes.

[0023] Furthermore, the thermosetting operation parameters are 100-120℃, 100-180min.

[0024] Furthermore, the preparation method of acrylate monomer I-1 is as follows: 4,4'-dihydroxydiphenyl sulfide, triethylamine, and phase transfer catalyst are added to toluene, magnetically stirred, slowly dissolved in an ice-water bath, and then 2-cyanoacryloyl chloride is added. The reaction is carried out at room temperature, and the product is obtained after the reaction is completed.

[0025] Furthermore, the preparation method of acrylate monomer II-1 is as follows: 4,4'-dimercaptodiphenyl sulfide, triethylamine, and a phase transfer catalyst are added to toluene, followed by the addition of 2-cyanoacryloyl chloride. The reaction is carried out in an ice-water bath, and the product is obtained after the reaction is completed.

[0026] Fourthly, the present invention provides the application of the optical resin described in the second aspect in microprisms or microlenses.

[0027] Compared with the prior art, the present invention has achieved the following beneficial effects: (1) The present invention uses acrylate monomers I-1 and II-1 to polymerize and prepare acrylate polymers. Through the synergistic cooperation of acrylate monomers I-1 and II-1 in a specific molar ratio, and then mixed with diisocyanate, polythiol compounds, etc., the prepared optical resin has high refractive index and high light transmittance.

[0028] (2) The present invention uses inexpensive and readily available raw materials and conventional processes to prepare optical resin materials. The process is simple and easy to industrialize. Detailed Implementation

[0029] Unless otherwise specified, all percentages and ratios used herein are based on the weight of the entire composition, and all measurements were performed at 25°C and normal pressure.

[0030] Unless otherwise stated, all temperatures are expressed in degrees Celsius.

[0031] This invention may include (open-ended) the components of this invention as well as other ingredients or elements described herein, or may consist substantially of the components of this invention as well as other ingredients or elements described herein.

[0032] As used herein, “includes” means the elements described, or their structural or functional equivalents, plus any other elements not described.

[0033] Unless the context otherwise suggests, the terms “having” and “including” are also to be interpreted as open-ended.

[0034] As used herein, "consistent with substantially" means that the invention may include components other than those recited in the claims, but only if the added components do not substantially alter the essential and novel characteristics of the claimed invention. Preferably, such additives will be absent or present only in trace amounts. However, it is possible to include up to about 10% by weight of materials that could substantially alter the essential and novel characteristics of the claimed invention, provided that the utility (rather than the extent of utility) of the compound is maintained.

[0035] All ranges described herein include endpoints, including those describing ranges "between" two values. Terms such as "approximately," "usually," "substantially," etc., will be interpreted as modifying a term or value so that it is not absolute and does not relate to prior art. Such terms will be defined by the circumstances and terms they modify, when such terms are understood by one of ordinary skill in the art. This includes, at least, expected experimental, technical, and instrumental errors for a given technique used to measure the value.

[0036] The technical solution of the present invention will be further described below with reference to specific embodiments.

[0037] Example 1 This embodiment provides a method for preparing acrylate monomer I-1. Under nitrogen protection, 4,4'-dihydroxydiphenyl sulfide (2.18 g, 10 mmol), triethylamine (2.02 g, 20 mmol), and TEBA (22.8 mg, 0.1 mmol) were added to 100 mL of toluene. The mixture was magnetically stirred and slowly dissolved in an ice-water bath. Then, 2-cyanoacryloyl chloride (2.31 g, 20 mmol) was added dropwise, and the reaction was carried out at room temperature for 10 h. After the reaction was completed, the mixture was filtered under reduced pressure. The filtrate was washed with deionized water and sodium bicarbonate solution, respectively, to obtain an organic phase solution. The solution was dried over anhydrous sodium sulfate, filtered, and the solvent was evaporated. The solution was purified by column chromatography to obtain 3.27 g of acrylate monomer I-1.

[0038] The reaction route is shown below: Example 2 This embodiment provides a method for preparing acrylate monomer II-1. Under nitrogen protection, 4,4'-dimercaptodiphenyl sulfide (2.5 g, 10 mmol), triethylamine (2.02 g, 20 mmol), and TEBA (22.8 mg, 0.1 mmol) were added to 100 mL of toluene and magnetically stirred. The mixture was slowly dissolved in an ice-water bath. 2-cyanoacryloyl chloride (2.31 g, 20 mmol) was added dropwise in an ice-water bath, and the reaction was continued in an ice-water bath for 10 h. After the reaction was completed, the mixture was filtered under reduced pressure. The filtrate was washed with deionized water and sodium bicarbonate solution to obtain an organic phase solution. The solution was dried over anhydrous sodium sulfate, filtered, and the solvent was evaporated. The solution was purified by column chromatography to obtain 3.67 g of acrylate monomer II-1.

[0039] The reaction route is shown below: Example 3 This embodiment provides a method for preparing acrylate polymers. Acrylate monomer I-1 (0.376 g, 1 mmol) and acrylate monomer II-1 (0.408 g, 1 mmol) were added to 40 mL of isopropanol, followed by the addition of 0.1 wt% initiator tert-amyl acetate peroxide. The mixture was sonicated for 10 min to dissolve the acrylate monomers and initiator. After filtration, the mixture was heat-cured at 120 °C for 120 min and then cooled to obtain the final product.

[0040] Example 4 This embodiment provides a method for preparing acrylate polymers. Acrylate monomer I-1 (0.376 g, 1 mmol) and acrylate monomer II-1 (0.817 g, 2 mmol) were added to 50 mL of isopropanol, followed by the addition of 0.12 wt% initiator tert-amyl acetate peroxide. The mixture was sonicated for 10 min to dissolve the acrylate monomers and initiator. After filtration, the mixture was heat-cured at 120 °C for 140 min and then cooled to obtain the final product.

[0041] Example 5 This embodiment provides a method for preparing acrylate polymers. Acrylate monomer I-1 (0.376 g, 1 mmol) and 0.5 mmol acrylate monomer II-1 (0.204 g, 0.5 mmol) were added to 30 mL of isopropanol, followed by the addition of 0.1 wt% initiator tert-amyl acetate peroxide. The mixture was sonicated for 8 min to dissolve the acrylate monomers and initiator. After filtration, the mixture was heat-cured at 100 °C for 120 min and then cooled to obtain the final product.

[0042] Comparative Example 1 This comparative example provides a method for preparing acrylate polymers. Acrylate monomer I-1 (0.376 g, 1 mmol) and 3 mmol acrylate monomer II-1 (1.226 g, 3 mmol) were added to 60 mL of isopropanol, followed by the addition of 0.15 wt% initiator tert-amyl acetate peroxide. The mixture was sonicated for 15 min to dissolve the acrylate monomers and initiator. After filtration, the mixture was heat-cured at 120 °C for 160 min and then cooled to obtain the final product.

[0043] Comparative Example 2 This comparative example provides a method for preparing acrylate polymers. Acrylate monomer I-1 (1.13 g, 3 mmol) and acrylate monomer II-1 (0.408 g, 1 mmol) were added to 60 mL of isopropanol, followed by 0.15 wt% of initiator tert-amyl acetate peroxide. The mixture was sonicated for 15 min to dissolve the acrylate monomers and initiator. After filtration, the mixture was heat-cured at 110 °C for 180 min and then cooled to obtain the final product.

[0044] Comparative Example 3 This comparative example provides a method for preparing acrylate polymers. Add acrylate monomer I-1 (0.753 g, 2 mmol) to 40 mL of isopropanol, then add 0.1 wt% of initiator tert-amyl acetate peroxide, sonicate for 10 min to dissolve the acrylate monomer and initiator, filter, and then heat cure at 120 °C for 120 min, and cool to obtain the final product.

[0045] Comparative Example 4 This comparative example provides a method for preparing acrylate polymers. Add acrylate monomer II-1 (0.817 g, 2 mmol) to 40 mL of isopropanol, then add 0.1 wt% of initiator tert-amyl acetate peroxide, sonicate for 10 min to dissolve the acrylate monomer and initiator, filter, and then heat cure at 120 °C for 120 min, and cool to obtain the final product.

[0046] Comparative Example 5 This comparative example provides a method for preparing acrylate polymers. This comparative example is basically the same as Example 3 in operation, the only difference being the use of equimolar amounts of JP2013049823A. Replace the acrylate monomer I-1 of the present invention; use an intermediate molar amount of JP2013049823A. The acrylate monomer II-1 of the present invention can be substituted.

[0047] Example 6 Preparation of optical resins 60 parts of the acrylate polymer prepared in Example 3 were dispersed in 20 parts of phthalic diisocyanate and stirred to obtain a uniformly dispersed solution. Then, 0.5 parts of hexamethylenetetramine, 0.5 parts of di-n-butyl phosphate, and 0.5 parts of UV326 were added to the solution and stirred to obtain a uniformly dispersed solution. Add 20 parts of thiodiglycol to the solution obtained above, stir to obtain a mixed solution; pour the mixed solution into a mold, heat to 100℃ and polymerize for 10 hours to obtain an optical resin.

[0048] Example 7 Preparation of optical resins 60 parts of the acrylate polymer prepared in Example 4 were dispersed in 20 parts of phthalic dimethyl diisocyanate and stirred to obtain a uniformly dispersed solution. Then, 0.5 parts of trimethyltin chloride, 0.5 parts of di-n-butyl phosphate, and 0.5 parts of UV326 were added to the solution and stirred to obtain a uniformly dispersed solution. Add 20 parts of pentaerythritol tris(3-mercaptopropionic acid) ester to the solution obtained above, stir to obtain a mixed solution; pour the mixed solution into a mold, heat to 100℃ and polymerize for 10 hours to obtain an optical resin.

[0049] Example 8 Preparation of optical resins 60 parts of the acrylate polymer prepared in Example 5 were dispersed in 20 parts of phthalic dimethyl diisocyanate and stirred to obtain a uniformly dispersed solution. Then, 0.5 parts of triethylenediamine, 0.5 parts of di-n-butyl phosphate, and 0.5 parts of UV-531 were added to the solution and stirred to obtain a uniformly dispersed solution. Add 20 parts of thiodiglycol to the solution obtained above, stir to obtain a mixed solution; pour the mixed solution into a mold, heat to 100℃ and polymerize for 10 hours to obtain an optical resin.

[0050] Comparative Example 6 Preparation of optical resins 60 parts of the acrylate polymer prepared in Comparative Example 1 were dispersed in 20 parts of phthalic dimethyl diisocyanate and stirred to obtain a uniformly dispersed solution. Then, 0.5 parts of N,N-dimethyloctylamine, 0.5 parts of di-n-butyl phosphate, and 0.5 parts of UV326 were added to the solution and stirred to obtain a uniformly dispersed solution. Add 20 parts of thiodiglycol to the solution obtained above, stir to obtain a mixed solution; pour the mixed solution into a mold, heat to 100℃ and polymerize for 10 hours to obtain an optical resin.

[0051] Comparative Example 7 Preparation of optical resins 60 parts of the acrylate polymer prepared in Comparative Example 2 were dispersed in 20 parts of phthalic diisocyanate and stirred to obtain a uniformly dispersed solution. Then, 0.5 parts of hexamethylenetetramine, 0.5 parts of di-n-butyl phosphate, and 0.5 parts of UV326 were added to the solution and stirred to obtain a uniformly dispersed solution. Add 20 parts of tetra(mercaptomethyl)methane to the solution obtained above, stir to obtain a mixed solution; pour the mixed solution into a mold, heat to 100℃ and polymerize for 10 hours to obtain an optical resin.

[0052] Comparative Example 8 Preparation of optical resins 60 parts of the acrylate polymer prepared in Comparative Example 3 were dispersed in 20 parts of phthalic dimethyl diisocyanate and stirred to obtain a uniformly dispersed solution. Then, 0.5 parts of hexamethylenetetramine, 0.5 parts of di-n-butyl phosphate, and 0.5 parts of UV326 were added to the solution and stirred to obtain a uniformly dispersed solution. Add 20 parts of thiodiglycol to the solution obtained above, stir to obtain a mixed solution; pour the mixed solution into a mold, heat to 100℃ and polymerize for 10 hours to obtain an optical resin.

[0053] Comparative Example 9 Preparation of optical resins 60 parts of the acrylate polymer prepared in Comparative Example 4 were dispersed in 20 parts of phthalic diisocyanate and stirred to obtain a uniformly dispersed solution. Then, 0.5 parts of hexamethylenetetramine, 0.5 parts of di-n-butyl phosphate, and 0.5 parts of UV326 were added to the solution and stirred to obtain a uniformly dispersed solution. Add 20 parts of thiodiglycol to the solution obtained above, stir to obtain a mixed solution; pour the mixed solution into a mold, heat to 100℃ and polymerize for 10 hours to obtain an optical resin.

[0054] Comparative Example 10 Preparation of optical resins 60 parts of the acrylate polymer prepared in Comparative Example 5 were dispersed in 20 parts of phthalic diisocyanate and stirred to obtain a uniformly dispersed solution. Then, 0.5 parts of hexamethylenetetramine, 0.5 parts of di-n-butyl phosphate, and 0.5 parts of UV326 were added to the solution and stirred to obtain a uniformly dispersed solution. Add 20 parts of thiodiglycol to the solution obtained above, stir to obtain a mixed solution; pour the mixed solution into a mold, heat to 100℃ and polymerize for 10 hours to obtain an optical resin.

[0055] Performance testing The optical resins prepared in Examples 6-8 and Comparative Examples 6-10 were subjected to the following performance tests: 1. Refractive index and Abbe number: measured using a refractometer (model: ATAGONAR-4T).

[0056] 2. Light transmittance: Measured using a Hunterlab USVIS1839 colorimeter.

[0057] The test results of the optical resins prepared in Examples 6-8 and Comparative Examples 6-10 are shown in Table 1.

[0058] Table 1. Test results of optical resin performance As shown in Table 1, the optical resins prepared in Examples 6-8 of this invention exhibit high refractive index and transmittance, demonstrating excellent performance. In Comparative Examples 6-7, the molar ratio of acrylate monomer I-1 to acrylate monomer II-1 in the acrylate polymers was changed to 1:3 and 3:1, respectively, resulting in a decrease in refractive index and transmittance compared to the examples, proving that the molar ratio of acrylate monomer I-1 to acrylate monomer II-1 has a significant impact on the effect. In Comparative Examples 8-9, each acrylate polymer used only one acrylate monomer, and the effect was lower than that of Examples 6-8 and Comparative Examples 6-7, demonstrating the synergistic effect of acrylate monomer I-1 and acrylate monomer II-1, which improved the refractive index and transmittance of the optical resin.

Claims

1. An optical resin composition, characterized in that, Including (a) acrylate polymers; (b) diisocyanates; and (c) polythiols. The acrylate polymer is obtained by free radical polymerization of acrylate monomer I-1 and acrylate monomer II-1; the molar ratio of acrylate monomer I-1 to acrylate monomer II-1 is 1:0.5-2. The structural formula of the acrylate monomer I-1 is: ； The acrylate monomer II-1 has the following structural formula: 。 2. The optical resin composition according to claim 1, characterized in that, The optical resin composition also includes a catalyst, a release agent, and a UV absorber.

3. The optical resin composition according to claim 2, characterized in that, The optical resin composition comprises, by mass fraction, the following components: 45-60 parts acrylate polymer, 15-25 parts diisocyanate, 20-30 parts polythiol compound, 0.1-1 part catalyst, 0.5-1 part release agent, and 0.1-0.5 parts ultraviolet absorber.

4. The optical resin composition according to claim 2, characterized in that, The diisocyanate is at least one selected from phthalic diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, 4,4-dicyclohexylmethane diisocyanate and hydrogenated phthalic diisocyanate. And / or, The polythiol compound is at least one of thiodiglycol, 2,3-dithio(2-mercapto)-1-propanethiol, tetra(mercaptomethyl)methane, pentaerythritol tetra(3-mercaptopropionic acid) ester, pentaerythritol tri(3-mercaptopropionic acid) ester, pentaerythritol tetra(3-mercaptobutyric acid) ester, and bis(mercaptomethyl)-3,6,9-trithiaundecane-1,11-dithiol; And / or, The catalyst is triethylenediamine, hexamethylenetetramine, N,N-dimethyloctylamine, dibutyltin dichloride, or trimethyltin chloride; And / or, The release agent includes at least one of di-n-butyl phosphate and nonylphenol polyoxyethylene ether phosphate. And / or, The ultraviolet absorber is at least one of UV326, UV327, UV329, UV-531, UV-9, and UV-234.

5. An optical resin, characterized in that, The optical resin is prepared using the optical resin composition according to any one of claims 1-4 as a raw material.

6. The optical resin as described in claim 5, characterized in that, The optical resin has a refractive index of 1.65-1.8 and a light transmittance greater than 94%.

7. The method for preparing the optical resin as described in claim 5, characterized in that, Includes the following steps: (1) Disperse the acrylate polymer in diisocyanate, stir to obtain a uniformly dispersed solution, then add catalyst, release agent and ultraviolet absorber to the solution, stir to obtain a uniformly dispersed solution; (2) Add polythiol compound to the solution obtained in step (1), stir to obtain a mixed solution; pour the mixed solution into a mold, heat it to polymerize it, and obtain an optical resin.

8. The preparation method according to claim 7, characterized in that, The polymerization temperature is 80-100℃; the polymerization time is 10-14 hours. And / or, The acrylate polymer is prepared by thermosetting: acrylate monomers I-1 and II-1 are added to an organic solvent, then an initiator is added, and the acrylate monomers and initiator are dissolved by sonication. After filtration, the polymer is thermoset to obtain the final product.

9. The preparation method according to claim 8, characterized in that, The organic solvent is at least one of acetone and isopropanol; And / or, The ultrasound time is 5-20 minutes; And / or, The thermosetting operation parameters are 100-120℃ and 100-180min.

10. The application of the optical resin as described in claim 5 in microprisms or microlenses.

Images