Preparation method of modified acrylate optical material with high abbe number

Abstract

The invention relates to a preparation method of a high-abbe-number modified acrylate optical material, which is characterized in that monomers for synthesizing the optical material contain modified methyl methacrylate, an acrylate monomer with hydroxyl, a polymethacrylate monomer and high-refractive-index epoxy resin, the modified methyl methacrylate is obtained by polyaddition reaction of methyl methacrylate, methacrylic acid and allyl methacrylate, and the mass ratio of methyl methacrylate, methacrylic acid and allyl methacrylate is (15-20): (3-5): (5-10). The abbe number, the hardness, the visible light transmittance, the impact resistance, the thermal stability, the ultraviolet aging resistance, the curvature stability and other properties of the optical material prepared by the method are effectively improved. The preparation method is simple in procedure, safe and controllable, no waste is discharged in the preparation process, and the green and environment-friendly industrial production requirement can be met.

Description

Technical Field

[0001] The invention relates to a method for preparing a modified acrylate optical material, in particular to a method for preparing a high-Abbe-number modified acrylate optical material with high transmittance, safety and low toxicity. Background Art

[0002] Abbe number, also known as dispersion coefficient. The same transparent medium has different refractive indices for light of different wavelengths. The white light visible to the human eye is composed of light of different wavelengths. When the transparent medium refracts white light, dispersion occurs. The Abbe number is an index used to represent the dispersion ability of a transparent medium. When visible light passes through the lens of glasses, due to the existence of the Abbe number, the light of each color will be deflected at different angles, affecting the image quality. The Abbe number of the human eye is 58.6. The closer the Abbe number of the lens is to the value of the human eye, the clearer the field of vision will be, and the phenomenon of blurred dispersion will not occur. However, lenses with an Abbe number below 30 have severe dispersion. Wearing glasses with a low Abbe number will produce adverse visual effects. Long-term wear will cause damage to the eyes. For teenagers, it may aggravate myopia and blur the colors and shapes seen.

[0003] At present, the mainstream eyeglass lenses in China can be roughly divided into three systems: acrylic (PMMA, polymethyl methacrylate), polycarbonate, and polyurethane. The refractive index of PMMA, which was originally used as lens material, was about 1.49, and it was not wear-resistant and easily deformed when exposed to heat. It was later replaced by CR-39. From 2000 to 2002, South Korea's KOC Chemical Company developed acrylic monomers of 1.56 (Abbe number 35) and 1.60 (Abbe number 32). The material cost is lower than that of CR39 and MR series materials, occupying most of the low and medium refractive index market. The Abbe number (34-36) of 1.56 acrylic lenses on the market can no longer meet consumers' demand for higher imaging quality.

[0004] PMMA was first cured by bulk polymerization, but bulk polymerization does not add a dispersion medium. After the polymerization reaction reaches a certain stage, the viscosity of the system is high, which is prone to automatic acceleration. The heat of the polymerization reaction is also difficult to remove, which can cause local overheating, leading to uneven reaction, widening the molecular weight distribution of the polymer, yellowing of the product and generation of bubbles, thereby damaging the polymer.

[0005] In order to overcome the shortcomings of bulk polymerization, the preparation of PMMA products is currently divided into two stages: pre-polymerization in a reactor and post-polymerization in a mold. This segmented polymerization method is mainly to eliminate the impact of volume shrinkage during the polymerization of methyl methacrylate and prevent cracking and the appearance of lines on the product surface. However, the disadvantages of segmented polymerization are that the process is complicated, the total reaction time is long, and precise temperature control is required. The viscosity of the monomer needs to be continuously monitored during the heating process. Otherwise, the viscosity of the monomer will be extremely high after the self-acceleration phenomenon occurs, making it difficult to pour into the mold. The reaction tolerance is low, and the impact resistance, surface hardness, curvature stability, and UV resistance of PMMA lenses are also inferior to those of mainstream lenses. Summary of the invention

[0006] In view of the above problems in the prior art, the present invention provides a method for preparing a high Abbe number modified acrylate optical material. The optical material prepared by the method has effectively improved Abbe number, hardness, visible light transmittance, impact resistance, thermal stability, resistance to ultraviolet aging and curvature stability. The preparation method has simple procedures, is safe and controllable, and no waste is discharged during the preparation process, which can meet the requirements of green and environmentally friendly industrial production.

[0007] To achieve the above object, the present invention provides the following technical solutions: A method for preparing a high Abbe number modified acrylate optical material, the method comprising the following steps: I. Weigh the following components according to weight ratio: a) 15 to 25 parts by weight of methyl methacrylate; b) 5 to 20 parts by weight of modified methyl methacrylate; c) 5 to 30 parts by weight of one or more acrylate monomers having a hydroxyl group; d) 5 to 40 parts by weight of one or more polymethacrylate monomers; e) 10 to 40 parts by weight of one or more high refractive index epoxy resins, the refractive index of which is greater than 1.57; f) 0.01 to 0.6 parts by weight of ultraviolet light absorber; g) 0.01 to 0.3 parts by weight of initiator; h) 0.01 to 0.3 parts by weight of a release agent; i) 0.01 to 0.3 parts by weight of a molecular weight regulator; The modified methyl methacrylate is obtained by polyaddition reaction of methyl methacrylate, methacrylic acid and allyl methacrylate, and the mass ratio of the three is (15-20): (3-5): (5-10); II. First, add the ultraviolet absorber to methyl methacrylate, and place it in a stirring device for uniform stirring after ultrasonic dispersion treatment; after the ultraviolet absorber is completely dissolved, add the modified methyl methacrylate, hydroxy acrylate monomer and multi-methacrylate monomer in sequence, and then add the high refractive index epoxy resin monomer; after stirring evenly, add the molecular weight regulator, release agent and initiator, stir at room temperature until completely dissolved, and then use a vacuum pump to evacuate the liquid mixture to remove air; III. The liquid mixture obtained in step II is filtered through a filter under pressure with an inert gas and then poured into a lens mold. The lens mold is sealed and placed in a constant temperature drying blower for primary curing through a heating program. After the mold is opened and cleaned, the lens substrate is obtained.

[0008] In the preparation method as described above, preferably, the acrylate monomer having a hydroxyl group is selected from one or more of hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl methacrylate, hydroxypropyl acrylate, hydroxybutyl methacrylate, hydroxybutyl acrylate, 2-hydroxypropyl acrylate and 2,3-dihydroxypropyl acrylate.

[0009] In the preparation method as described above, preferably, the multi-methacrylate monomer is selected from: one or more of neopentyl glycol dimethacrylate, trimethylolpropane monoallyl ester, trimethylolpropane trimethacrylate, ethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, and 1,12-dodecanol dimethacrylate.

[0010] In the preparation method as described above, preferably, the high refractive index epoxy resin is at least two of bisphenol A epoxy resin, brominated bisphenol A epoxy resin, bisphenol F epoxy resin, polyphenol glycidyl ether epoxy resin, aliphatic glycidyl ether epoxy resin, glycidyl ester epoxy resin and phenolic epoxy resin.

[0011] In the preparation method as described above, preferably, the ultraviolet absorber is selected from: phenyl o-hydroxybenzoate, o-nitroaniline, 2-(2'hydroxy-3',5'-di-tert-phenyl)-5-chlorobenzotriazole, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octyloxybenzophenone, monobenzoic acid resorcinol ester, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, hexamethylphosphoric triamide, UV-234, UV-327, UV-329, SLF-1130 and one or more thereof.

[0012] In the preparation method as described above, preferably, the initiator is selected from: one or more of tert-butyl maleic acid peroxide, diacetyl peroxide, benzene peroxide, cumene hydroperoxide, dicumyl peroxide, tert-butyl hydroperoxide, lauroyl peroxide, amino acid, sulfonic acid, azobisisobutyronitrile or azobisisoheptylonitrile.

[0013] In the preparation method as described above, preferably, the release agent is butyl phosphate.

[0014] In the preparation method as described above, preferably, the molecular weight regulator is α-methylstyrene dimer or 2,6-di-tert-butyl-p-cresol.

[0015] The preparation method as described above, preferably, the preparation method of the modified methyl methacrylate is as follows: take 15-20 parts by weight of methyl methacrylate, add 5-10 parts by weight of allyl methacrylate, perform ultrasound, stir for 5-10 minutes after ultrasound, introduce nitrogen, start to uniformly heat to 75-79°C, keep the temperature constant for 2.5~3.5 hours, then continue to heat to 81-83°C, add 3-5 parts by weight of methacrylic acid at a uniform rate during the heating process, seal and place in a constant temperature blast drying oven under a nitrogen atmosphere at normal pressure, keep the temperature at 81-83°C for 3-4 hours, take out, cool to room temperature and collect.

[0016] In the preparation method as described above, preferably, the total amount of the hydroxyl-containing acrylate monomer and the polymethacrylate monomer used is between about 10-60 parts by weight, more preferably between 15-35 parts by weight, based on 100 parts by weight of all components.

[0017] The methyl methacrylate of component a in the present invention is the main resin material in the composition, and its Abbe number is as high as 57.4, which plays an important role in improving the Abbe number of the lens, and acts as a main solvent to make the various components uniformly mixed and reacted.

[0018] The modified methyl methacrylate in component b increases the interfacial adhesion by introducing carboxyl and allyl groups, and generates a partial network structure during curing. Compared with the chain-structured polymethyl methacrylate, the appearance of the network structure partially improves the heat resistance, impact strength and surface hardness of the lens after curing, giving the lens excellent mechanical properties. At the same time, the modified methyl methacrylate itself is a high Abbe number and high transmittance optical material, and the optical properties of the material can be improved as the content increases.

[0019] The hydroxyl-containing acrylate monomer in component C is copolymerized with each component to obtain an acrylic resin with active hydroxyl groups in the side chain. At the same time, hydroxyl groups are typical polar groups that can provide cross-linking functions for methyl methacrylate, polymethacrylate, and epoxy resin. Part of the hydroxyl groups react with free carboxyl groups in the composition to esterify, thereby increasing the reaction conversion rate and increasing the overall hardness of the lens. At the same time, part of the hydroxyl groups combine with the hydroxyl groups in the mold to increase the adhesion between the composition and the mold, and prevent the lens from being demolded and forming lines during curing.

[0020] The polymethacrylate in component d is highly stable by combining with other components. Due to the chain transfer of free radical polymerization, the monomers with more than three functional groups participate in the polycondensation reaction during the polycondensation process, as well as the existence of radiation crosslinking and chemical crosslinking reactions, branch structures are extended from the linear molecular chain. Due to the existence of long branched chains, the toughness of the lens after curing is further increased, improving the impact resistance of the lens.

[0021] The epoxy resin in component e is a high refractive index material. The viscosity and refractive index of the composition can be adjusted by using two or more different epoxy resin monomers at the same time, which is convenient for stirring and pouring operations, improves the refractive index of the finished lens, compensates for the shortcoming of the low refractive index of the methyl methacrylate monomer, stabilizes the curvature of the lens, and the use of epoxy resin with a low curing shrinkage rate can also reduce the volume shrinkage rate of the lens after curing.

[0022] Component f, the ultraviolet absorber, is a light stabilizer. It mainly shields or absorbs the energy of ultraviolet rays, quenches singlet oxygen, and decomposes hydroperoxides into inactive substances, so that the polymer can eliminate or slow down the possibility of photochemical reactions under the radiation of light, prevent or delay the process of photoaging, and thus extend the service life of the lens.

[0023] The beneficial effects of the present invention are: (1) By modifying methyl methacrylate, the regularity of the monomer is improved. When modified methyl methacrylate is added to the raw materials, the carbon-carbon double bonds in some acrylate groups are opened during the curing process and polymerize with active groups such as carbon-carbon double bonds on other monomers, adding a network structure to the chain structure of methyl methacrylate. Both primary and secondary crosslinks exist in the cured product, making the structure more compact and improving the problem of PMMA lenses being brittle and easy to age. At the same time, modified methyl methacrylate itself is a high Abbe number, high transmittance optical material, and the optical properties of the material can be improved as its content increases.

[0024] (2) The addition of acrylate monomers containing hydroxyl functional groups makes the structure of the composite material dense, and the cross-linking effect of the long-chain structure brought about by the addition of polymethacrylate greatly improves the hardness and toughness, two important mechanical properties of the lens.

[0025] (3) The hydroxyl and ether groups contained in the epoxy resin structure have high polarity, which causes strong intermolecular forces between the epoxy molecules and the adjacent interfaces. By selecting epoxy resins with small volume shrinkage, the impact of eliminating the prepolymerization step on lens performance can be greatly reduced.

[0026] (4) Adding ultraviolet absorbers has good ultraviolet absorption performance, ensuring that its light transmittance is not affected while enhancing the lens's anti-ultraviolet and anti-ultraviolet aging performance.

[0027] (5) The high Abbe number modified acrylate optical material of the present invention is prepared by thermal curing the above components, and a high Abbe number optical material with high Abbe number, high visible light transmittance, high mechanical strength, high curvature stability and good impact resistance is obtained at a relatively low processing cost.

[0028] (6) The preparation method of the present invention has simple procedures, is safe and controllable, and has no waste discharge during the preparation process, thus meeting the requirements of green and environmentally friendly industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is the infrared spectrum of modified methyl methacrylate 1 prepared in Preparation Example 1. DETAILED DESCRIPTION

[0032] In order to better understand the present invention, the present invention is described below in conjunction with preferred embodiments, but it should be understood that these descriptions are only for better illustrating the features of the present invention, rather than limiting the claims of the present invention. Materials not specifically noted in the present invention are not limited and can be purchased on the market or prepared according to conventional methods known to those skilled in the art.

[0033] All raw materials of the present invention have no particular restrictions on their purity. The present invention preferably uses analytically pure or conventional purity requirements in the field of polypropylene material preparation. All raw materials of the present invention, their brands and abbreviations are conventional brands and abbreviations in the field, and each brand and abbreviation is clear and unambiguous in the field of its related use. All professional and scientific terms used in the text have the same meanings as those familiar to those skilled in the art.

[0034] In addition, any methods and materials similar or equivalent to those described herein can be applied to the methods of the present invention. The preferred implementation methods and materials described herein are for demonstration purposes only.

[0035] Preparation Example 1: Take 170g of methyl methacrylate and add 100g of allyl methacrylate for ultrasonication. After ultrasonication, stir for 10min, introduce nitrogen, and start to uniformly heat up to 75°C and keep the temperature constant for 3.5h. Then continue to heat up to 83°C. During the heating process, 30g of methacrylic acid is uniformly added. Under a nitrogen atmosphere at normal pressure, the mixture is sealed and placed in a constant temperature forced air drying oven at 81°C for 3h. The mixture is taken out and cooled to room temperature. The modified methyl methacrylate 1 is collected.

[0036] Figure 1 is the infrared spectrum of modified methyl methacrylate 1. After checking with the standard spectrum of the group, Figure 1 The IR peaks are: 3086cm -1 and 3019cm -1 Unsaturated CH stretching vibration absorption, 1650cm -1 There is C=C stretching vibration at 2973cm -1 is the stretching vibration of CR3-CH3, 2956cm -1 、2867cm -1 With 2923cm -1 、2851cm -1 -CH3- and -CH2- stretching vibrations, 1727 cm -1 and 1639cm -1 It is the stretching vibration of the carbon-oxygen double bond on the ester group, 1456 cm -1 It shows the presence of asymmetric shear vibration of -CH3- and -CH2-, and 1383cm -1 The stretching vibration of methyl group is at 1300cm -1 and 1100cm -1 There is a strong absorption peak of CO stretching vibration, 990cm -1 and 910cm -1 The strong absorption peaks of methine and methylene are 720 cm -1 This indicates the presence of peaks of more than 4 methylene groups.

[0037] The infrared spectrum shows that some carbon-carbon double bonds in the modified methyl methacrylate are opened and react with the carbon-carbon double bonds on the methacrylic acid and allyl methacrylate molecules. A few double bonds react with the groups on the side chain, such as the acrylate group, to form a trace network structure. Therefore, straight-chain alkyl, carboxyl, methyl ester and allyl ester groups exist in the reaction product at the same time. The absorption peak of unsaturated CH in the figure indicates that there are monomers that do not participate in the reaction and their double bonds are not opened.

[0038] Preparation Example 2: Take 150g of methyl methacrylate and add 75g of allyl methacrylate for ultrasonication. After ultrasonication, stir for 7min, introduce nitrogen, and start to uniformly heat up to 77°C and keep the temperature constant for 3h. Then continue to heat up to 82°C. During the heating process, 50g of methacrylic acid is added uniformly. Under a nitrogen atmosphere at normal pressure, the mixture is sealed and placed in a constant temperature forced air drying oven at 82°C for 3.5h. After being taken out and cooled to room temperature, the modified methyl methacrylate 2 is obtained.

[0039] Preparation Example 3: Take 200 g of methyl methacrylate and add 50 g of allyl methacrylate for ultrasonication. After ultrasonication, stir for 5 minutes, introduce nitrogen, and start to uniformly heat up to 79°C and keep the temperature constant for 2.5 hours. Then continue to heat up to 81°C. During the heating process, 40 g of methacrylic acid is uniformly added. Under a nitrogen atmosphere at normal pressure, the mixture is sealed and placed in a constant temperature forced air drying oven at 81°C for 4 hours. After being taken out and cooled to room temperature, the modified methyl methacrylate 3 is obtained.

[0040] Example 1 First, 0.3g UV-234 and 0.3g UV-327 were added to 20g methyl methacrylate, and after ultrasonic dispersion treatment, the mixture was stirred for 10min using a magnetic stirrer. After the ultraviolet absorber was completely dissolved, 20g modified methyl methacrylate 1, 15g hydroxypropyl methacrylate, and 10g trimethylolpropane monoallyl ester were added in sequence, followed by 15g bisphenol A epoxy resin and 20g bisphenol F epoxy resin. After stirring for 30min, 0.25g 2,6-di-tert-butyl-p-cresol, 0.15g butyl phosphate, and 0.15g azobisisobutyronitrile were added, and the mixture was stirred at room temperature for 15min. A vacuum pump was then used to evacuate the mixture at a vacuum degree of -0.1MPa for 15min. The mixture from which air was excluded was pressurized with nitrogen and filtered through a 0.45µm capsule filter, and then cast into a glass mold. The mixture was cured once by a constant temperature drying blower (see Table 1 for program parameters). After the mold was opened and cleaned, a high Abbe number substrate was obtained.

[0041]

[0042] Comparative Example 1 First, 0.3g UV-234 and 0.3g UV-327 were added to 20g methyl methacrylate, and after ultrasonic dispersion treatment, the mixture was stirred for 10min using a magnetic stirrer. After the ultraviolet absorber was completely dissolved, 15g hydroxypropyl methacrylate and 10g trimethylolpropane monoallyl ester were added in sequence, followed by 15g bisphenol A epoxy resin and 20g bisphenol F epoxy resin. After stirring for 30min, 0.25g 2,6-di-tert-butyl-p-cresol, 0.15g butyl phosphate and 0.15g azobisisobutyronitrile were added, and the mixture was stirred at room temperature for 15min. A vacuum pump was then used to evacuate the mixture at a vacuum degree of -0.1MPa for 15min. The mixture from which air was excluded was pressurized with nitrogen and filtered through a 0.45µm capsule filter, and then cast into a well-assembled glass mold. The mixture was once cured by a constant temperature drying blower (see Table 1 for program parameters). After the mold was opened and cleaned, a high Abbe number substrate was obtained.

[0043] Example 2 First, 0.3g UV-234 and 0.3g UV-327 were added to 25g methyl methacrylate, and after ultrasonic dispersion treatment, the mixture was stirred for 10min using a magnetic stirrer. After the ultraviolet absorber was completely dissolved, 20g modified methyl methacrylate 1, 13g hydroxypropyl methacrylate, and 5g trimethylolpropane monoallyl ester were added in sequence, followed by 20g bisphenol A epoxy resin and 17g bisphenol F epoxy resin. After stirring for 30min, 0.25g 2,6-di-tert-butyl-p-cresol, 0.15g butyl phosphate, and 0.15g azobisisobutyronitrile were added, and the mixture was stirred at room temperature for 15min. A vacuum pump was then used to evacuate the mixture at a vacuum degree of -0.1MPa for 15min. The mixture from which air was excluded was pressurized with nitrogen and filtered through a 0.45µm capsule filter, and then cast into a glass mold. The mixture was cured once by a constant temperature drying blower (see Table 1 for program parameters). After the mold was opened and cleaned, a high Abbe number substrate was obtained.

[0044] Comparative Example 2 First, 0.3g UV-234 and 0.3g UV-327 were added to 25g methyl methacrylate, and after ultrasonic dispersion treatment, they were stirred for 10min using a magnetic stirrer. After the ultraviolet absorber was completely dissolved, 20g modified methyl methacrylate 1 and 5g trimethylolpropane monoallyl ester were added in sequence, followed by 20g bisphenol A epoxy resin and 17g bisphenol F epoxy resin. After stirring for 30min, 0.25g 2,6-di-tert-butyl-p-cresol, 0.15g butyl phosphate and 0.15g azobisisobutyronitrile were added, stirred at room temperature for 15min, and then vacuumed for 15min at a vacuum degree of -0.1MPa using a vacuum pump. The mixture from which air was excluded was pressurized with nitrogen and filtered through a 0.45µm capsule filter, and then cast into a assembled glass mold, and cured once by a constant temperature drying blower (see Table 1 for program parameters). After the mold was opened and cleaned, a high Abbe number substrate was obtained.

[0045] Example 3 First, 0.3g UV-234 and 0.3g UV-327 were added to 20g methyl methacrylate, and after ultrasonic dispersion treatment, the mixture was stirred for 10min using a magnetic stirrer. After the ultraviolet absorber was completely dissolved, 15g modified methyl methacrylate 2, 20g hydroxypropyl methacrylate, and 15g trimethylolpropane monoallyl ester were added in sequence, followed by 20g bisphenol A epoxy resin and 10g bisphenol F epoxy resin. After stirring for 30min, 0.25g 2,6-di-tert-butyl-p-cresol, 0.15g butyl phosphate, and 0.15g azobisisobutyronitrile were added, and the mixture was stirred at room temperature for 15min. A vacuum pump was then used to evacuate the mixture at a vacuum degree of -0.1MPa for 15min. The mixture from which air was excluded was pressurized with nitrogen and filtered through a 0.45µm capsule filter, and then cast into a assembled glass mold. The mixture was once cured by a constant temperature drying blower (see Table 2 for program parameters). After the mold was opened and cleaned, a high Abbe number substrate was obtained.

[0046]

[0047] Comparative Example 3 First, 0.3g UV-234 and 0.3g UV-327 were added to 20g methyl methacrylate, and after ultrasonic dispersion treatment, the mixture was stirred for 10min using a magnetic stirrer. After the ultraviolet absorber was completely dissolved, 15g modified methyl methacrylate 2 and 20g hydroxypropyl methacrylate were added in sequence, followed by 20g bisphenol A epoxy resin and 10g bisphenol F epoxy resin. After stirring for 30min, 0.25g 2,6-di-tert-butyl-p-cresol, 0.15g butyl phosphate and 0.15g azobisisobutyronitrile were added, and the mixture was stirred at room temperature for 15min. A vacuum pump was then used to evacuate the mixture at a vacuum degree of -0.1MPa for 15min. The mixture from which air was excluded was pressurized with nitrogen and filtered through a 0.45µm capsule filter, and then cast into a assembled glass mold. The mixture was cured once by a constant temperature drying blower (see Table 2 for program parameters). After the mold was opened and cleaned, a high Abbe number substrate was obtained.

[0048] Example 4 Take 30g of methyl methacrylate, add 15g of modified methyl methacrylate 3, 15g of hydroxypropyl methacrylate, 10g of trimethylolpropane monoallyl ester in sequence, and then add 15g of bisphenol A epoxy resin and 15g of bisphenol F epoxy resin; after stirring for 30min, add 0.25g of 2,6-di-tert-butyl-p-cresol, 0.15g of butyl phosphate, and 0.15g of azobisisobutyronitrile, stir at room temperature for 15min, and then use a vacuum pump to evacuate at a vacuum degree of -0.1MPa for 15min, pressurize the mixture with air excluded with nitrogen, filter it through a 0.45µm capsule filter, pour it into a assembled glass mold, and cure it once by a constant temperature drying blower (see Table 2 for program parameters). After opening the mold and cleaning, a high Abbe number substrate can be obtained.

[0049] Comparative Example 4 Take 30g of methyl methacrylate, add 15g of modified methyl methacrylate 3, 15g of hydroxypropyl methacrylate, 10g of trimethylolpropane monoallyl ester in sequence, and then add 30g of phenolic epoxy resin; after stirring for 30min, add 0.25g of 2,6-di-tert-butyl-p-cresol, 0.15g of butyl phosphate, and 0.15g of azobisisobutyronitrile, stir at room temperature for 15min, and then use a vacuum pump to evacuate at a vacuum degree of -0.1MPa for 15min, pressurize the mixture with air excluded with nitrogen, filter it through a 0.45µm capsule filter, pour it into the assembled glass mold, and cure it once by a constant temperature drying blower (see Table 2 for program parameters). After opening the mold and cleaning, a high Abbe number substrate can be obtained.

[0050] Experimental Example 1 Performance Testing The high Abbe number lenses prepared in the technical solutions of Examples 1 to 4 and Comparative Examples 1 to 4 were subjected to performance tests: their Abbe number, transmittance in the visible light band, substrate hardness and ultraviolet transmittance were tested. The specific test results are shown in Table 3; Table 4 is the test results of the impact resistance, anti-aging performance and curvature error of the lenses.

[0051]

[0052] By comparing the test results of Example 1 and Comparative Example 1, it can be seen that adding modified methyl methacrylate to the resin raw material improves the surface hardness, impact resistance and heat aging resistance of the lens, and improves the Abbe number and visible light transmittance of the lens, and reduces the curvature error of the lens.

[0053] By comparing the test results of Example 2 and Comparative Example 2, it can be seen that the addition of hydroxyl-containing acrylate to the resin raw material significantly improves the surface hardness of the lens, improves the impact resistance and visible light transmittance of the lens to a certain extent, improves the scratch resistance of the lens surface, and reduces the influence of human operation on the pass rate in industrial production.

[0054] By comparing the test results of Example 3 and Comparative Example 3, it can be seen that the polymethacrylate monomer has the effect of increasing the toughness of the lens in the composition. After adding the polymethacrylate monomer, the lens has improved impact resistance and can provide a certain degree of protection to the user in different usage scenarios.

[0055] Comparing the test results of Example 4 and Comparative Example 4, it can be seen that the performance differences brought about by the different high refractive index epoxy resins can be seen in its effect of improving the refractive index and curvature of the lens. At the same time, the presence of epoxy resins with specific viscosity and low curing shrinkage can improve the viscosity of the monomer and the shrinkage during the curing process, reduce the difficulty of casting, and improve the qualified rate of lens curvature.

[0056] By comparing the test results of Examples 1, 2, 3, Comparative Examples 1, 2, 3 with Example 4 and Comparative Example 4, it can be seen that the addition of the ultraviolet absorber significantly improves the anti-ultraviolet aging performance of the lens, the photochemical reaction is greatly slowed down, and the service life of the lens is thus extended; at the same time, the transmittance of ultraviolet light is reduced, which meets the requirements of GB10810 for the ultraviolet spectrum region in glasses.

Claims

1. A method for preparing a high Abbe number modified acrylate optical material, characterized in that: The method comprises the following steps: I. Weigh the following components according to weight ratio: a) 15 to 25 parts by weight of methyl methacrylate; b) 5 to 20 parts by weight of modified methyl methacrylate; c) 5 to 30 parts by weight of one or more acrylate monomers having a hydroxyl group; d) 5 to 40 parts by weight of one or more polymethacrylate monomers; e) 10 to 40 parts by weight of one or more high refractive index epoxy resins, the refractive index of which is greater than 1.57; f) 0.01 to 0.6 parts by weight of ultraviolet light absorber; g) 0.01 to 0.3 parts by weight of initiator; h) 0.01 to 0.3 parts by weight of a release agent; i) 0.01 to 0.3 parts by weight of a molecular weight regulator; The modified methyl methacrylate is obtained by polyaddition reaction of methyl methacrylate, methacrylic acid and allyl methacrylate, and the mass ratio of the three is (15-20): (3-5): (5-10); II. First, add the ultraviolet absorber to methyl methacrylate, and place it in a stirring device for uniform stirring after ultrasonic dispersion treatment; after the ultraviolet absorber is completely dissolved, add the modified methyl methacrylate, hydroxy acrylate monomer and multi-methacrylate monomer in sequence, and then add the high refractive index epoxy resin monomer; after stirring evenly, add the molecular weight regulator, release agent and initiator, stir at room temperature until completely dissolved, and then use a vacuum pump to evacuate the liquid mixture to remove air; III. The liquid mixture obtained in step II is filtered through a filter under pressure with an inert gas and then poured into a lens mold. The lens mold is sealed and placed in a constant temperature drying blower for primary curing through a heating program. After the mold is opened and cleaned, the lens substrate is obtained.

2. The preparation method according to claim 1, characterized in that The acrylic acid ester monomer having a hydroxyl group is selected from one or more of hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl methacrylate, hydroxypropyl acrylate, hydroxybutyl methacrylate, hydroxybutyl acrylate, 2-hydroxypropyl acrylate and 2,3-dihydroxypropyl acrylate.

3. The preparation method according to claim 1, characterized in that: The polymethacrylate monomer is selected from one or more of neopentyl glycol dimethacrylate, trimethylolpropane monoallyl ester, trimethylolpropane trimethacrylate, ethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, and 1,12-dodecanol dimethacrylate.

4. The preparation method according to claim 1, characterized in that: The high refractive index epoxy resin is at least two of bisphenol A epoxy resin, brominated bisphenol A epoxy resin, bisphenol F epoxy resin, polyphenol glycidyl ether epoxy resin, aliphatic glycidyl ether epoxy resin, glycidyl ester epoxy resin and phenolic epoxy resin.

5. The preparation method according to claim 1, characterized in that: The ultraviolet absorber is selected from: phenyl o-hydroxybenzoate, o-nitroaniline, 2-(2'hydroxy-3',5'-di-tert-phenyl)-5-chlorobenzotriazole, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octyloxybenzophenone, monobenzoic acid resorcinol ester, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, hexamethylphosphoric triamide, UV-234, UV-327, UV-329, SLF-1130 and one or more thereof.

6. The preparation method according to claim 1, characterized in that: The initiator is selected from one or more of tert-butyl maleic acid peroxide, diacetyl peroxide, benzene peroxide, cumene hydroperoxide, dicumyl peroxide, tert-butyl hydroperoxide, lauroyl peroxide, amino acid, sulfonic acid, azobisisobutyronitrile or azobisisoheptylonitrile.

7. The preparation method according to claim 1, characterized in that: The release agent is butyl phosphate.

8. The preparation method according to claim 1, characterized in that: The molecular weight regulator is α-methylstyrene dimer or 2,6-di-tert-butyl-p-cresol.

9. The preparation method according to any one of claims 1 to 8, characterized in that The preparation method of the modified methyl methacrylate is as follows: 15-20 parts by weight of methyl methacrylate is added with 5-10 parts by weight of allyl methacrylate for ultrasonication, stirring for 5-10 minutes after ultrasonication, introducing nitrogen, and uniformly heating to 75-79° C. for 2.5-3.5 hours, then continuing to heat to 81-83° C., uniformly adding 3-5 parts by weight of methacrylic acid during the heating process, sealing and placing in a constant temperature blast drying oven under a nitrogen atmosphere at normal pressure and keeping the constant temperature at 81-83° C. for 3-4 hours, taking out, cooling to room temperature, and collecting.

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