High-transmittance protective glasses and preparation method thereof

Abstract

The invention discloses high-light-transmittance protective glasses and a preparation method thereof, and belongs to the technical field of protective glasses, the high-light-transmittance protective glasses comprise a modified polycarbonate base material, a modified hard polyurethane coating and an AR coating, the modified polycarbonate base material comprises the following components by weight: 65-85 parts of modified polycarbonate, 2-4 parts of inorganic nanoparticles, 1-3 parts of an anti-aging agent, 1-3 parts of an anti-aging agent, and 1-3 parts of an anti-aging agent. 5-10 parts of an additive; the modified hard polyurethane coating is prepared from modified polyurethane main glue and a curing agent, and the modified polyurethane main glue is prepared from the following components in parts by weight: 60 to 80 parts of polycarbonate diol, 3 to 11 parts of a chain extender, 20 to 38 parts of diisocyanate, 0.1 to 0.5 part of a catalyst and 0.2 to 1 part of a terminating agent; a rigid binaphthalene structure with relatively good refractive index and light scattering property is introduced into polycarbonate, so that the impact resistance is improved while the light transmittance is improved; in addition, an ultraviolet absorption functional component is grafted in the rigid polyurethane, so that the loss and yellowing risks of the functional component are reduced; and then, under the combined action with an AR coating, the high-light-transmittance protective glasses are prepared.

Description

Technical Field

[0001] This invention relates to the field of protective eyewear technology, specifically to a high-transmittance protective eyewear and its preparation method. Background Technology

[0002] Transparent protective eyewear is a crucial optical material with significant applications, widely used in various aspects of life, such as helmet visors, laboratory protective eyewear, and welding goggles. As technology advances and research becomes more refined, the demands on equipment also increase. This is especially true for specialized applications like medical endoscopes and laboratory protective eyewear, which require high-transmittance protective eyewear to ensure safety while minimizing visual interference, improving comfort, and reducing error rates. Currently, transparent protective eyewear is primarily made from transparent polymers such as polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), and polycarbonate (PC). PC, with its high light transmittance, high impact resistance, and good heat resistance, is a commonly used transparent polymer material. However, it suffers from poor UV resistance and scratch resistance. Furthermore, the manufacture of UV-resistant PC protective eyewear often involves the addition of inorganic, organic, or inorganic-organic composite UV absorbers, which are prone to loss over time, causing yellowing and affecting light transmittance, thus failing to meet requirements. Summary of the Invention

[0003] To overcome the shortcomings of the existing technology, this invention provides a high-transmittance protective eyewear and its preparation method. The high-transmittance protective eyewear comprises a modified polycarbonate substrate, a modified rigid polyurethane coating, and an AR coating. The modified polycarbonate substrate is prepared by the combined action of modified polycarbonate, inorganic nanoparticles, and 5-10 parts of additives. The modified rigid polyurethane coating is prepared by a modified polyurethane base adhesive and a curing agent. The AR coating is one or a combination of SiO2 and TiO2. Specifically, using a highly symmetrical naphthalene structure as the polycarbonate main chain can reduce light scattering. Simultaneously, the branched naphthalene structure results in low crystallinity of the polycarbonate, further reducing light loss during material transmission. The rigid naphthalene ring also effectively improves the impact resistance of the protective eyewear. Grafting the UV-absorbing functional component 2,4,6-tris(4'-butoxy-2'-hydroxyphenyl)-triazine into the polyurethane coating improves the material's UV resistance while reducing the risk of yellowing due to UV absorber loss. Furthermore, adding an anti-reflective AR coating to the surface reduces visible light reflection, further improving light transmittance.

[0004] The purpose of this invention is to provide a high-transmittance protective eyewear and its preparation method.

[0005] This invention is achieved through the following technical solution:

[0006] A high-transmittance protective eyewear, comprising a modified polycarbonate substrate, a modified rigid polyurethane coating, and an AR coating. The modified polycarbonate substrate, by weight, comprises the following components: 65-85 parts modified polycarbonate, 2-4 parts inorganic nanoparticles, and 5-10 parts additives. The modified rigid polyurethane coating comprises a modified polyurethane base adhesive and a curing agent. The modified polyurethane base adhesive, by weight, comprises the following components: 60-80 parts polycarbonate diol, 3-11 parts chain extender, 20-38 parts diisocyanate, 0.1-0.5 parts catalyst, and 0.2-1 part terminator. The AR coating is one or a combination of SiO2 and TiO2.

[0007] In one specific embodiment, the modified polycarbonate has the structural formula shown in Formula 1:

[0008]

[0009] In one specific embodiment, the preparation of the modified polycarbonate includes the following steps:

[0010] S1. Raw material pretreatment

[0011] (1,1'-binaphthyl)-2,2'-diamine and epoxide phenyl ethane were pre-dehydrated in a vacuum drying oven at 100-120°C for 18-24 hours;

[0012] S2. Epoxy ring-opening

[0013] Under nitrogen protection, (1,1'-binaphthyl)-2,2'-diamine and phenylene oxide were dissolved in anhydrous tetrahydrofuran, and ZnCl2 was added as a catalyst. The reaction was heated to 70-80℃ and stirred for 12-24 hours until the reaction was completed. The mixture was then cooled, concentrated, and purified by column chromatography to obtain the modified polycarbonate monomer.

[0014] S3. Preparation of modified polycarbonate

[0015] The modified polycarbonate monomer was dehydrated in a vacuum drying oven at 100-120℃ for 18-24 hours and then placed in a reaction vessel. Under nitrogen protection, diphenyl carbonate and catalyst Ti(OBu)4 were added, and the temperature was raised to 150-180℃ and stirred until melted. Low-temperature transesterification was carried out by raising the temperature and lowering the pressure for high-temperature polycondensation. Heating was stopped, nitrogen was introduced and phosphite was added to terminate the reaction. The mixture was cooled, purified by precipitation with anhydrous ethanol, and dried to obtain modified polycarbonate.

[0016] In one specific embodiment, in step S2, the amount of epoxide phenylene oxide used is 2.01-2.2 times the molar amount of (1,1'-binaphthyl)-2,2'-diamine; and the amount of ZnCl2 catalyst used is 0.1-1 wt% of (1,1'-binaphthyl)-2,2'-diamine.

[0017] In a specific embodiment, in step S3, the amount of modified polycarbonate monomer is 2.05-2.1 times the molar amount of diphenyl carbonate; the amount of Ti(OBu)4 is 0.01-0.1 wt%; the low-temperature transesterification temperature is 180-220℃, and the time is 4-6 hours; the high-temperature polycondensation temperature is 200-220℃, the vacuum degree is reduced to below 0.133 kPa, and the time is 4-8 hours; the number-average molecular weight of the modified polycarbonate is 20000-45000.

[0018] In one specific embodiment, the preparation of the modified polyurethane base adhesive includes the following steps:

[0019] S1. Raw material pretreatment

[0020] Polycarbonate diol is pre-dehydrated in a vacuum drying oven at 100-115℃ for 3-5 hours; the chain extender is placed in a vacuum drying oven at 95℃ for 3-5 hours to dehydrate; and the diisocyanate is placed in a vacuum drying oven at 60-100℃ for 3-8 hours to dehydrate and melt into a liquid state.

[0021] S2. Prepolymer Synthesis

[0022] Under nitrogen protection, polycarbonate diol was added to a dry reactor and heated to 60-70°C with stirring to melt it; diisocyanate was added, and catalyst was added after half an hour; the reaction was heated to obtain the prepolymer;

[0023] S3. Chain extension and crosslinking

[0024] Cool the prepolymer to 55-60℃, add the chain extender, and stir rapidly to react;

[0025] S4. Terminate the reaction to obtain the main adhesive.

[0026] Once the required viscosity is reached, turn off the heating, add the terminator, stir for 0.5-1 hour, degas under vacuum, package and discharge the material to obtain the modified polyurethane main adhesive, and store it in a sealed container.

[0027] In one specific embodiment, the diisocyanate is 4,4'-methylenebis(phenyl isocyanate), and the amount of 4,4'-methylenebis(phenyl isocyanate) is 1.32-1.6 times the molar amount of polycarbonate diol (R value 1.01-1.8); the catalyst is dibutyltin dilaurate; the reaction temperature is 85-95°C, and the reaction time is 5-6 hours.

[0028] In one specific embodiment, the chain extender 2,4,6-tris(4'-butoxy-2'-hydroxyphenyl)-triazine has a chain extension time of 3-5 hours.

[0029] In one specific embodiment, the terminating agent is methanol.

[0030] In one specific embodiment, the curing agent is one or more of ethylenediamine and diethylenetriamine.

[0031] Another object of the present invention is to provide a method for preparing high-transmittance protective glasses, comprising the following steps:

[0032] S1. Prepare the polyurethane base adhesive and curing agent according to the ratio, stir well, and set aside;

[0033] S2. After dehydrating the modified polycarbonate in a vacuum drying oven at 80-120℃ for 24 hours, place it in a mixer, add inorganic nanoparticles and additives, and heat and mix evenly; transfer it to an extruder for extrusion molding; the molded material is cooled by water and cut into granules by a granulator to obtain modified polycarbonate granules.

[0034] S3. Take the modified polycarbonate granules and place them in a mixer, heat and melt them, then inject them into a mold and pressurize them to obtain a substrate; soak the substrate in isopropanol for 1-1.5 hours and then rinse it with deionized water; then apply the prepared polyurethane to the inner and outer surfaces of the substrate and dry it in an 80℃ oven for 18-24 hours.

[0035] S4. Rinse the surface with deionized water and apply an AR coating to the inner and outer surfaces by magnetron sputtering.

[0036] In one specific embodiment, in step S1, the ratio of the polyurethane base adhesive to the curing agent is 10:1.05-10:1.1.

[0037] In one specific embodiment, in step S2, the inorganic nanoparticles are at least one of nano-SiO2 or Al2O3, and the amount is 1-4 wt%; the additive is styrene-acrylonitrile copolymer, and the amount is 5-10 wt%; the mixing temperature is 250-280℃.

[0038] In a specific embodiment, in step S3, the melting temperature is 160-180℃, the mold temperature is 50-120℃, the substrate thickness is 2-5mm, and the inner and outer polyurethane coating thickness is 1-5μm; in step S4, the AR coating thickness is 0.1-1μm, the magnetron sputtering power is 120-140W, and the coating time is 1-1.5 hours.

[0039] Beneficial effects

[0040] This invention provides a high-transmittance protective eyewear and its preparation method. The high-transmittance protective eyewear comprises a modified polycarbonate substrate, a modified rigid polyurethane coating, and an AR coating. The modified polycarbonate substrate is prepared by the combined action of modified polycarbonate, inorganic nanoparticles, and additives. The modified rigid polyurethane coating is prepared by polymerization of polycarbonate diol, chain extender, diisocyanate, catalyst, and terminator. The AR coating is one or a combination of SiO2 and TiO2. The use of a highly symmetrical naphthalene structure as the polycarbonate backbone reduces light scattering. Simultaneously, the branched naphthalene structure results in low crystallinity of the polycarbonate, further reducing light loss during transmission and imparting high transmittance. The rigid naphthalene ring effectively improves the impact resistance of the protective eyewear. Grafting the UV-absorbing functional component 2,4,6-tris(4'-butoxy-2'-hydroxyphenyl)-triazine into the polyurethane coating significantly improves the material's UV resistance and greatly reduces the risk of yellowing. Furthermore, the addition of an anti-reflective AR coating further enhances the transmittance. Attached Figure Description

[0041] Figure 1 Synthetic routes for modified polycarbonate and modified rigid polyurethane;

[0042] Figure 2 The 1H NMR spectrum of the modified polycarbonate monomer;

[0043] Figure 3 Infrared spectra of modified polycarbonate, modified polycarbonate monomer, modified rigid polyurethane coating, and unmodified rigid polyurethane coating. Detailed Implementation

[0044] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0045] Unless otherwise specified, the experimental methods used in the embodiments are conventional methods, and the materials and reagents used are commercially available unless otherwise specified.

[0046] The raw materials used in the examples and comparative examples are described below:

[0047] Diisocyanate: 4,4'-methylenebis(phenyl isocyanate) (MDI), 98%, product number M813280, purchased from Shanghai Maclean Biochemical Technology Co., Ltd.

[0048] Polycarbonate diol (PCDL): Mn2000, 99%, purchased from Hubei Dahao Chemical Co., Ltd.;

[0049] Chain extender 1: 2,4,6-tris(4'-butoxy-2'-hydroxyphenyl)-triazine, 98%, product number T3870, purchased from TCI (Shanghai) Chemical Industry Development Co., Ltd.

[0050] Chain extender 2: 1,4-Butanediol, commercially available;

[0051] Organotin catalyst: Dibutyltin dilaurate (DBTDL), 95%, product number D806313, purchased from Shanghai Maclean Biochemical Technology Co., Ltd.

[0052] (1,1'-binaphthyl)-2,2'-diamine: 97%, product number B803445, purchased from Shanghai Maclean Biochemical Technology Co., Ltd.

[0053] Epoxy phenyl ethane: 98%, product number R799498, purchased from Shanghai Maclean Biochemical Technology Co., Ltd.;

[0054] Tetrabutyl titanate (Ti(OBu)4): 98%, product number CP38330, purchased from Jiaxing Zhejia Biotechnology Co., Ltd.

[0055] Diphenyl carbonate: 99%, purchased from Shanghai Maclean Biochemical Technology Co., Ltd.

[0056] PC granule additive: Styrene-acrylonitrile copolymer (SAN-GMA), Mw165000, item number 323310, purchased from Beijing Bailingwei Technology Co., Ltd.

[0057] PC polycarbonate (bisphenol A type): purchased from Wuhan Jiyesheng Chemical Co., Ltd.;

[0058] Curing agent: Triethylenediamine, commercially available;

[0059] Modified polycarbonate: self-made, preparation method as follows:

[0060] S1. Raw material pretreatment: The specific steps are as follows.

[0061] (1,1'-binaphthyl)-2,2'-diamine and epoxide phenyl ethane were pre-dehydrated in a vacuum drying oven at 115°C for 24 hours;

[0062] S2. Epoxy ring-opening

[0063] Under nitrogen protection, (1,1'-binaphthyl)-2,2'-diamine (1 equivalent) and phenylene oxide (2.1 equivalent) were dissolved in anhydrous tetrahydrofuran, and ZnCl2 (0.5 wt%) was added as a catalyst. The reaction was heated to 80°C and stirred for 24 hours until the reaction was completed. The mixture was then cooled, concentrated, and purified by column chromatography to obtain the modified polycarbonate monomer.

[0064] S3. Preparation of modified polycarbonate 1

[0065] The modified polycarbonate monomer (2.1 equivalents) was dehydrated in a vacuum drying oven at 115°C for 24 hours and then placed in a reaction vessel. Under nitrogen protection, diphenyl carbonate (1 equivalent) and Ti(OBu)4 (0.03 wt%) were added and mixed. The mixture was heated to 175°C and stirred until melted. The mixture was then heated to 210°C for low-temperature transesterification for 4 hours. The mixture was then heated to 200°C and the vacuum was reduced to 0.133 kPa for high-temperature polycondensation for 6 hours. Heating was stopped, nitrogen was introduced, and phosphite was added to terminate the reaction. The product was cooled, dissolved in THF, and purified by precipitation with anhydrous ethanol. The product was dried to obtain modified polycarbonate 1 with a number average molecular weight of 20,000.

[0066] Modified polycarbonate 2: The preparation method is the same as that of modified polycarbonate 1, except that the amount of Ti(OBu)4 is 0.15wt%.

[0067] Modified polyurethane base adhesive: self-made, preparation method as follows:

[0068] S1. Raw material pretreatment

[0069] Polycarbonate diol was pre-dehydrated in a vacuum drying oven at 115°C for 3 hours; the chain extender was placed in a vacuum drying oven at 95°C for 3 hours to dehydrate; and 4,4'-methylenebis(phenyl isocyanate) was placed in a vacuum drying oven at 100°C for 3 hours to dehydrate and melt into a liquid state.

[0070] S2. Prepolymer Synthesis

[0071] Under nitrogen protection, dehydrated polycarbonate diol (1 equivalent) was added to a dry reactor, and the mixture was heated to 60-70°C and stirred to melt. A metered amount of molten 4,4'-methylenebis(phenyl isocyanate) (R value 1.1) was slowly added dropwise. After half an hour, dibutyltin dilaurate (0.3 wt%) was added to accelerate the reaction. The mixture was then heated to 90°C and reacted for 5 hours to obtain a prepolymer with MDI end-capping.

[0072] S3. Chain extension and crosslinking

[0073] The prepolymer was cooled to 60°C, and a chain extender solution of 2,4,6-tris(4'-butoxy-2'-hydroxyphenyl)-triazine (4.3 wt%) was added. The mixture was stirred rapidly for 3 hours.

[0074] S4. Terminate the reaction to obtain the main adhesive.

[0075] Once the required viscosity is reached, turn off the heating, add methanol (0.3 wt%) to terminate the reaction, stir for 1 hour, degas under vacuum, package and discharge the material to obtain the main adhesive, and seal and store it.

[0076] Unmodified polyurethane base adhesive: self-made, the preparation method is the same as that of modified UV-resistant rigid polyurethane base adhesive, the difference is that chain extender 1 is replaced by chain extender 2, that is, the polyurethane chain segments are not grafted with UV-resistant functional components.

[0077] It should be noted that the term "equivalent" used in this invention refers to "molar equivalent".

[0078] Unless otherwise specified, all components and raw materials used in the embodiments and comparative examples of this invention are commercially available, and the same type of components and raw materials are used in each parallel experiment.

[0079] Examples and Comparative Examples

[0080] A type of high-transmittance protective eyewear, the weight parts of which are shown in Table 1, is prepared as follows:

[0081] (1) Prepare the polyurethane base adhesive and curing agent in a ratio of 10:1.05, stir well, and set aside;

[0082] (2) Preparation of modified polycarbonate granules: After dehydrating the modified polycarbonate in a vacuum drying oven at 120°C for 24 hours, it was placed in a mixer, and then inorganic nanoparticles SiO2 (3wt%) and styrene-acrylonitrile copolymer (10wt%) were added and heated to 260°C and mixed evenly; it was transferred to an extruder for extrusion molding; the molded material was cooled by water and cut into granules by a granulator to obtain modified polycarbonate granules;

[0083] (3) Take the modified polycarbonate granules and place them in a mixer. Heat the mixture to 180°C to melt it. Then pour it into a mold (120°C) and pressurize it to obtain a substrate with a thickness of 4 mm. Soak the substrate in isopropanol for 1.5 hours and then rinse it with deionized water to activate the surface. Then apply the prepared polyurethane to the inner and outer surfaces of the substrate with a thickness of 5 μm and dry it in an oven at 80°C for 24 hours.

[0084] (4) Rinse the surface with deionized water, and then coat the inner and outer surfaces with an AR coating of 0.5 μm thickness. The vacuum coating magnetron sputtering filter is 140W and the coating time is 1.5 hours.

[0085] Table 1 High-transmittance protective glasses (parts by weight)

[0086]

[0087]

[0088] The high-transmittance protective glasses prepared in the examples and comparative examples were subjected to the following performance tests, and the results are shown in the attached figures and Table 2, respectively.

[0089] 1. Proton NMR spectroscopy: The synthesized modified polycarbonate monomer sample was dissolved in deuterated DMSO to prepare a 1.0 wt% solution. The NMR spectrum of the sample was measured using a proton NMR spectrometer at 400 MHz. The results are as follows: Figure 2 As shown.

[0090] 2. Infrared Spectroscopy: Modified polycarbonate 1, modified polycarbonate monomers, the modified rigid polyurethane coating of Example 1, and the unmodified rigid polyurethane coating of Comparative Example 2 were mixed with potassium bromide at a ratio of 1:50 to prepare a tablet. An Avatar 380 spectrometer was used for this test. Before testing, a blank background was scanned, and then the tablet sample was placed in the sample for testing. The scanning range was 500-4000 cm⁻¹. -1 The result is as follows Figure 3 As shown.

[0091] 3. Impact resistance (peak force): Using a drop hammer impact tester and according to ANSI Z87.1 standard, the modified polycarbonate substrate was injection molded into a sample strip of 5cm*5cm*2cm, the impact energy was set to 15J, and the maximum impact force that the sample strip could withstand was recorded.

[0092] 4. Abrasion Resistance: Tested according to ASTM D4060 standard under conditions of 50% ± 10% relative humidity. Prepare a protective eyewear sample with a smooth, scratch-free surface, measuring 100mm long × 100mm wide × 2mm thick. Select a CS-10 wheel with a 500g load, a rotation speed of 60 ± 5 rpm, and a total of 500 revolutions. Weigh the mass difference (Δm) before and after wear. Determine the abrasion resistance using the following formula: For protective eyewear coatings: Δm < 10 mg / 500 r is considered acceptable.

[0093] 5. Anti-aging properties: Take a silicone rubber sheet cut to 1×1×0.22cm and place it in a UV aging test chamber. Set the temperature to room temperature and humidity to 55%. After aging for one week, measure the percentage decrease in its performance.

[0094] 6. Transmittance and Haze: According to ASTM D1003 standard, a protective eyewear sample with a smooth, scratch-free surface (50mm x 50mm x 2mm) was prepared and wiped with alcohol. A CIE standard D65 illuminant was used as the light source, and tests were conducted at 23℃ ± 2℃ and 50% ± 10% relative humidity. The incident, transmitted, and scattered luminous flux were recorded, and the transmittance (Tt) and haze were calculated using the following formulas.

[0095]

[0096] Degree (H): Luminous flux transmitted through the material; Φi: luminous flux of incident light; Φd: luminous flux of scattered light that deviates from the incident direction by more than 2.5° after passing through the material.

[0097] 7. Yellowing Index (Y1): Tested according to ASTM E313 standard. Prepare a protective eyewear sample with a length of 40mm × width of 40mm × thickness of 2mm, place it in the measurement hole, use a BaSO4 coated board as the background board, and D65 as the test light source. Read the X, Y, and Z values ​​of the CIE XYZ colorimetric system, and calculate the yellowing index according to the following formula:

[0098] Table 2 Performance test results of high-transmittance protective glasses

[0099]

[0100]

[0101] From the appendix Figure 2 The 1H NMR spectrum shows that the integral number is consistent with the number of hydrogen atoms in the molecule, and the shifts of each hydrogen atom in the spectrum are consistent with their chemical environment, indicating that the modified polycarbonate monomer has been successfully synthesized.

[0102] From the appendix Figure 3 It can be seen that the peak value appears between 2940-2850 cm. -1 The stretching vibration belonging to CH, 1735cm -1 The signal is absorbed near carbonate groups and -C=O in -NHCOO, at 1100-1060 cm⁻¹. -1 Attributable to carbonate groups and -NHCOO- COC- absorption, 1520cm -1 The characteristic absorption at this point belongs to the carbon-nitrogen single bond -CN. In the spectrum of the modified rigid polyurethane coating, this absorption is not present in the 2270-2250 cm⁻¹ region. -1 Absorption of -NCO was observed in the range, and at 1632 cm⁻¹. -1 A peak appears near the carbon-nitrogen double bond -C=N-, at 1300-1200 cm⁻¹. -1 and 1055-1000cm -1 Ph-O- absorption occurs at 830 cm⁻¹ -1 Characteristic signals of para-benzene substitution can still be seen at this location, while no such signal is observed at 3500 cm⁻¹. -1The presence of a -OH signal nearby indicates that the UV-absorbing functional component was successfully grafted into the polyurethane, and the isocyanate group reacted completely. In the modified polycarbonate, the characteristic -OH signal peak in the 3600-3500 cm⁻¹ range disappeared, while the stretching vibration of the secondary amine -NH⁻ in the monomer and the naphthalene ring in the monomer at 1590 cm⁻¹ were retained. -1 With 1449cm -1 The bending vibration peak is also 804 cm. -1 and 745cm -1 The fingerprint signal indicates that the monomer successfully reacted with diphenyl carbonate to produce a polymer, which is a modified polycarbonate.

[0103] As can be seen from Table 2, compared with the comparative examples, the protective eyewear composite materials prepared by introducing more rigid binaphthalene as the main chain of polycarbonate in Examples 1-3 showed increased impact resistance, indicating good impact and penetration resistance. Meanwhile, the modified rigid polyurethane coatings in Examples 4-7 lost less than 2.3 mg of mass after 500 revolutions of wear, indicating good scratch resistance. It should be noted that if the polyurethane coating in Example 7 is too thick, uneven curing may occur, which may lead to a decrease in wear resistance.

[0104] As can be seen from Table 2, the introduction of the high-refractive-index binaphthyl structural unit makes polycarbonate also have a high refractive index; at the same time, the rigid and symmetrical skeleton of binaphthyl can reduce light scattering, thereby reducing haze and greatly improving light transmittance; in addition, polycarbonate has branches and low crystallinity, which can further reduce the loss of light when passing through the material. With the introduction of anti-reflective AR coating material, excellent optical performance with a high transmittance of 97% can be obtained.

[0105] Furthermore, the introduction of the UV-absorbing functional structure 2,4,6-tris(4'-butoxy-2'-hydroxyphenyl)-triazine into the polyurethane chain greatly improves the anti-aging ability, reduces the rate of yellowing, and maintains high light transmittance. On the other hand, grafting UV absorbers instead of additives can reduce the risk of functional component loss, thereby extending the service life.

[0106] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A high-transmittance protective eyewear, comprising a modified polycarbonate substrate, a modified rigid polyurethane coating, and an AR coating, wherein the modified polycarbonate substrate, by weight, comprises the following components: 65-85 parts modified polycarbonate, 2-4 parts inorganic nanoparticles, and 5-10 parts additives; the modified rigid polyurethane coating comprises a modified polyurethane base adhesive and a curing agent, wherein the modified polyurethane base adhesive, by weight, comprises the following components: 60-80 parts polycarbonate diol, 3-11 parts chain extender, 20-38 parts diisocyanate, 0.1-0.5 parts catalyst, and 0.2-1 part terminator; the modified polycarbonate has the structural formula shown in Formula 1:

2. The high-transmittance protective glasses as described in claim 1, characterized in that, The AR coating is one or a combination of SiO2 or TiO2.

3. The high-transmittance protective glasses as described in claim 1, characterized in that, The preparation of the modified polycarbonate includes the following steps: S1. Raw material pretreatment (1,1'-binaphthyl)-2,2'-diamine and epoxide phenyl ethane were pre-dehydrated in a vacuum drying oven at 100-120°C for 18-24 hours; S2. Epoxy ring-opening Under nitrogen protection, (1,1'-binaphthyl)-2,2'-diamine and phenylene oxide were dissolved in anhydrous tetrahydrofuran, and ZnCl2 was added as a catalyst. The reaction was heated to 70-80℃ and stirred for 12-24 hours until the reaction was completed. The mixture was then cooled, concentrated, and purified by column chromatography to obtain the modified polycarbonate monomer. S3. Preparation of modified polycarbonate The modified polycarbonate monomer was dehydrated in a vacuum drying oven at 100-120℃ for 18-24 hours and then placed in a reaction vessel. Under nitrogen protection, diphenyl carbonate and catalyst Ti(OBu)4 were added, and the temperature was raised to 150-180℃ and stirred until melted. Low-temperature transesterification was carried out by raising the temperature and lowering the pressure for high-temperature polycondensation. Heating was stopped, nitrogen was introduced and phosphite was added to terminate the reaction. The mixture was cooled, purified by precipitation with anhydrous ethanol, and dried to obtain modified polycarbonate.

4. The high-transmittance protective glasses as described in claim 3, characterized in that, In step S2, the amount of epoxide phenylene oxide used is 2.01-2.2 times the molar amount of (1,1'-binaphthyl)-2,2'-diamine; the amount of ZnCl2 catalyst used is 0.1-1 wt% of (1,1'-binaphthyl)-2,2'-diamine; in step S3, the amount of modified polycarbonate monomer used is 2.05-2.1 times the molar amount of diphenyl carbonate; the amount of Ti(OBu)4 used is 0.01-0.1 wt%; the low-temperature transesterification temperature is 180-220℃, and the time is 4-6 hours; the high-temperature polycondensation temperature is 200-220℃, the vacuum degree is reduced to below 0.133 kPa, and the time is 4-8 hours.

5. The high-transmittance protective glasses as described in claim 1, characterized in that, The modified polycarbonate has a number-average molecular weight of 20,000-45,000.

6. The high-transmittance protective glasses as described in claim 1, characterized in that, The inorganic nanoparticles are at least one of nano-SiO2 or Al2O3, and the additive is a styrene-acrylonitrile copolymer.

7. The high-transmittance protective glasses as described in claim 1, characterized in that, The preparation of the modified polyurethane base adhesive includes the following steps: S1. Raw material pretreatment Polycarbonate diol is pre-dehydrated in a vacuum drying oven at 100-115℃ for 3-5 hours; the chain extender is placed in a vacuum drying oven at 95℃ for 3-5 hours to dehydrate; and the diisocyanate is placed in a vacuum drying oven at 60-100℃ for 3-8 hours to dehydrate and melt into a liquid state. S2. Prepolymer Synthesis Under nitrogen protection, polycarbonate diol was added to a dry reactor and heated to 60-70°C with stirring to melt it; diisocyanate was added, and catalyst was added after half an hour; the reaction was heated to obtain the prepolymer; S3. Chain extension and crosslinking Cool the prepolymer to 55-60℃, add the chain extender, and stir rapidly to react; S4. Terminate the reaction to obtain the main adhesive. Once the required viscosity is reached, turn off the heating, add the terminator, stir for 0.5-1 hour, degas under vacuum, package and discharge the material to obtain the modified polyurethane main adhesive, and store it in a sealed container.

8. The high-transmittance protective glasses as described in claim 1, characterized in that, The diisocyanate is 4,4'-methylenebis(phenyl isocyanate); the catalyst is dibutyltin dilaurate; the chain extender is 2,4,6-tris(4'-butoxy-2'-hydroxyphenyl)-triazine; the terminator is methanol; and the curing agent is one or more of ethylenediamine and diethylenetriamine.

9. A method for preparing high-transmittance protective glasses as described in any one of claims 1 to 8, characterized in that, Includes the following steps: S1. Prepare the modified polyurethane base adhesive and curing agent in a ratio of 10:1.05-10:1.1, stir well, and set aside; S2. After dehydrating the modified polycarbonate in a vacuum drying oven at 80-120℃ for 24 hours, place it in a mixer, add inorganic nanoparticles and additives, and heat to 250-280℃ to mix evenly; transfer it to an extruder for extrusion molding; the molded material is cooled by water and cut into granules by a granulator to obtain modified polycarbonate granules. S3. Take the modified polycarbonate granules and place them in a mixer. Heat the mixture to 160-180℃ to melt it. Then pour it into a mold at 50-120℃ and press it to form a substrate with a thickness of 2-5mm. The substrate is immersed in isopropanol for 1-1.5 hours and then rinsed with deionized water; then the prepared polyurethane is applied to the inner and outer surfaces of the substrate with a thickness of 1-5 μm, and dried in an oven at 80℃ for 18-24 hours. S4. Rinse the surface with deionized water, and coat the inner and outer surfaces with an AR coating of 0.1-1μm thickness by magnetron sputtering at a power of 120-140W for 1-1.5 hours.

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