CN114874642B - Hypoxia microsphere with ultraviolet shielding shell structure and preparation method thereof - Google Patents

Abstract

The invention discloses an oxygen-deficient microsphere with an ultraviolet shielding shell structure and a preparation method thereof. The shell of anoxic microspheres is composed of SiO ₂ and ultraviolet shielding functional substances, the ratio of which is 1:(0.05-0.1), and the thickness of the shell is 10-30nm. It has dual functions of visible light transparency and oxygen barrier. The inner core of hypoxic microspheres is composed of resin matrix, hypoxic functional fillers and dye molecules, and the diameter of the inner core is 200-500 μm. The composition; the total content of hypoxic functional filler is 0.1-1% of the mass of the resin matrix, and the dye molecules are 0.1-0.5% of the mass of the resin matrix. The anoxic microspheres with an ultraviolet shielding shell structure can provide an anoxic environment for filtering ultraviolet radiation for organic dyes, and can effectively improve the stability of organic dyes under sunlight irradiation.

Description

Anoxic microspheres with ultraviolet shielding shell structure and preparation method thereof

Technical Field

The invention belongs to the field of organic dye stabilization, and particularly relates to an oxygen-deficient microsphere with an ultraviolet shielding shell structure and a preparation method thereof.

Background Art

Organic dyes are widely used in the industrial market due to their rich colors and high color rendering, and their annual output accounts for about a quarter of the dye output. The photostability of organic dyes is a key factor in determining their market application. The photodegradation process mainly includes: the dye is excited by light and transitions to the excited triplet state. The dye in the triplet state reacts with the ground state _O2 to generate singlet oxygen with strong oxidizing properties. The singlet oxygen attacks the dye to oxidize and decompose it. The presence of _O2 and ultraviolet rays is the main reason for inducing dye photodegradation. By physically isolating external _O2 and removing dissolved oxygen in the system, adding a functional shell with ultraviolet shielding effect to the outside, providing an ultraviolet filter and oxygen-deficient environment for organic dyes, the photostability of organic dyes can be effectively improved.

After being excited by light, the organic dye transitions to the triplet state and reacts with the ground state _O2 to generate singlet oxygen with oxidation activity, causing photo-oxidation of the dye. For singlet oxygen, a singlet oxygen scavenger can be added to react with it to generate peroxide, thereby reducing the interaction between singlet oxygen and the dye. In this process, the singlet oxygen scavenger and the dye are in a competitive relationship, and the singlet oxygen scavenger has a high reaction sensitivity and can quickly capture the singlet oxygen generated in the system, thereby inhibiting the oxidation of singlet oxygen on the organic dye.

At present, the stabilization technology for organic dyes is mainly achieved through two methods: UV shielding and _O2 blocking. Among them, for the regulation of oxygen content, the existing technology uses film layer or shell layer encapsulation technology to prevent the diffusion of oxygen. However, the disadvantage of this method is that it only plays a role in blocking external _O2 , and there is no corresponding solution for the dissolved oxygen existing in the system itself and the small amount of _O2 diffused into the interior. Therefore, the organic dye is still in an environment containing a small amount of _O2 molecules. By adding nanoparticles that can react with ground state oxygen to the system, the dissolved oxygen in the system is removed and the small amount of _O2 molecules diffused into the external environment are further consumed.

Microspheroidization or microencapsulation technology is to form a functional microparticle product with solid, liquid and other substances as the core structure, which has the effects of stabilizing and protecting the internal material, positioning and slow release. For organic dyes as core materials, usually inorganic materials and organic materials can be used as wall materials for coating the core materials. Common organic systems are to wrap the dye in a dense high molecular polymer. Through dye microencapsulation, it is wrapped in a dense high molecular film as a core material, so that the core material is isolated from the outside, and the original optical properties of the dye are maintained while avoiding contact with O ₂ , which can improve the dispersibility and light stability of the dye molecules. For example, in the patent with application number CN102146218A, urea and formaldehyde are used as microcapsule wall material monomers, and active dye microcapsules are prepared by in-situ polymerization, which better solves the problem of dye diffusivity and controls the dye release rate. In the patent with application number CN109107499A, oil-in-water (O/W) miniemulsion system is combined with phase inversion technology to prepare high molecular polymer microcapsules with high molecular polymer as raw material. Inorganic systems mainly use some functional inorganic nanoparticles as shells to form a core-shell structure to wrap the dye in the core. Patent CN111808436A discloses a method for preparing a new type of core-shell structure colored _SiO2 , which wraps the organic dye on the surface of _SiO2 , modifies the dye by adding a surfactant, and then wraps a layer of _SiO2 on the surface to obtain monodisperse and uniform dye-doped _SiO2 particles. Patent CN101440279A discloses a composite silicon shell structure fluorescent nanoparticle, which uses fluorescent dye as the core material and forms a _SiO2 core on the core surface by hydrolyzing TEOS, which can prevent the dye from leaking during application and directly contacting the organism.

At present, there are also methods for preparing dye microcapsules by integrating organic-inorganic materials. The main technology is that inorganic nano materials are used as carriers to adsorb dyes on the surface to form composite materials, and then they are wrapped in polymers to form organic-inorganic integrated microcapsules. For example, in the patent application number CN107138104A, organic dyes and stabilizers are adsorbed on the _SiO2 surface, and then added to an oil-water mixture to form paraffin droplets with _SiO2 particles inside. This method can encapsulate dyes and stabilizers in microcapsules at the same time, solving the problem that hindered phenol stabilizers are easily damaged by hydroxyl radicals in the system. In the patent application number CN109550465A, dyes are adsorbed on the surface of nano- _SiO2 and dispersed in the oil phase, and after forming a stable water-in-oil emulsion system, a hollow microcapsule with an inner cavity coated with nano- _SiO2 balls is formed by phase inversion technology. The introduction of _SiO2 enhances the encapsulation ability of polymer microcapsules for dyes. However, the dye and inorganic material combined by electrostatic adsorption still have dye desorption during use, and there is a certain probability that the dye will diffuse to the outside of the microcapsule after desorption.

The problem existing in the above technology is that the use of a dense polymer matrix or an inorganic hard shell as the _O2 barrier layer of the dye can block the diffusion of external _O2 to a certain extent, but does not solve the dissolved oxygen existing inside the system, and therefore fails to completely block the photooxidation reaction occurring when _O2 and dye molecules come into contact.

Summary of the invention

The purpose of the invention is to address the problem that organic dyes are prone to photooxidation/photoaging during the application process. The present invention provides an oxygen-deficient microsphere with a UV shielding shell structure. Another purpose of the present invention is to provide a method for preparing the above-mentioned oxygen-deficient microspheres, which can achieve the light stability of organic dyes during the application process.

The technical solution of the present invention is: an oxygen-deficient microsphere with an ultraviolet shielding shell structure, characterized in that the oxygen-deficient microsphere is composed of a shell and an inner core; wherein the shell of the oxygen-deficient microsphere is composed of _SiO2 and an ultraviolet shielding functional substance, the mass ratio of which is 1:(0.05-0.1), and the shell thickness is 10-30nm; the inner core of the oxygen-deficient microsphere is composed of a resin matrix, an oxygen-deficient functional filler and a dye molecule, and the inner core diameter is 200-500μm; the mass of the dye molecule is 0.1-0.5% of the mass of the resin matrix; the mass of the oxygen-deficient functional filler is 0.1-1% of the mass of the resin matrix.

Preferably, the UV shielding functional substance is any one of nano- _TiO2 or nano-ZnO or a combination of the two, and its particle size is 20-50nm. Preferably, the resin matrix is epoxy resin.

Preferably, the oxygen-deficient functional filler is composed of one or more of an oxygen barrier, an oxygen consuming agent or a singlet oxygen capture agent; wherein the oxygen barrier is a two-dimensional nanomaterial of montmorillonite or hydrotalcite; the oxygen consuming agent is nano magnesium silicide; as an oxygen consuming agent, it can react with dissolved oxygen in the system to generate lamellar _SiO2 , and the particle size of the nano magnesium silicide is 20-50nm; the singlet oxygen capture agent is one or more of 2,2,6,6-tetramethylpiperidinamine (TEMP), 1,3-diphenylisobenzofuran (DPBF) or 9,10-anthracenediyl-bis(methylene)dimalonic acid (ABDA), which is used to capture singlet oxygen in an excited state with strong oxidizing properties.

Preferably, the dye molecule is one of zinc phthalocyanine (ZnPc), chlorophyll (Chl), meta-tetraphenylsulfonate porphyrin zinc (Zn-TSPP) or magnesium tetraphenylporphyrin (MgTPP).

The present invention also provides a method for preparing the above-mentioned hypoxic microspheres, and the specific steps are as follows:

(1) Adding dye and hypoxic functional filler to curing agent, ultrasonically dispersing and setting aside;

(2) adding an emulsifier and a resin prepolymer into water to uniformly emulsify, adding the curing agent containing a dye and an oxygen-deficient functional substance prepared in step (1) into the emulsion system, and performing thermal curing in a water bath at 75 to 85° C. to obtain an oxygen-deficient microsphere core containing an organic dye;

(3) The ultraviolet shielding functional substance is uniformly dispersed in the silicon source, and the oxygen-deficient microsphere core prepared in step (2) is added and hydrolyzed and condensed on the surface to obtain the oxygen-deficient microsphere having a _SiO2 oxygen-deficient microsphere shell layer doped with the ultraviolet shielding functional substance.

The preferred emulsifier is one of OP-10, EL-40 or Tween-80; the amount of the emulsifier is 4-7% of the mass of water; the resin prepolymer is 2,2-bis(4-epoxypropoxyphenyl)propane (DGEBA), and the amount is 3-8% of the mass of water; the curing agent is one of meta-phenylenediamine (MXDA), diethylenetriamine (DETA) or triethylenetetramine (TETA); the amount of the curing agent is in an equal stoichiometric ratio to the resin prepolymer; the preferred curing temperature is 70-85°C, and the curing time is 2-5h; the silicon source is one of tetraethyl orthosilicate (TEOS) or methyl orthosilicate (TMOS), and the mass ratio of the silicon source to the resin matrix is 1:(3-7); the amount of the ultraviolet shielding functional substance is 0.1-0.5% of the mass of the resin matrix.

Beneficial effects:

The structure effectively inhibits the photodegradation rate of the organic dye. The advantages of the present invention are: the structure provides an oxygen-deficient environment for shielding ultraviolet radiation for the organic dye through the construction of the oxygen-deficient shell layer and the compound of the oxygen-deficient functional filler in the core, and effectively realizes the light stability of the organic dye during the application process.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a SEM schematic diagram of the ZnPc/EP@SiO ₂ microspheres prepared in Example 2;

FIG2 is a FESEM schematic diagram of the surface of ZnPc/EP@SiO ₂ microspheres prepared in Example 2;

FIG3 is an absorption spectrum of the ZnPc/EP microspheres prepared in Example 2 after UV aging at different times;

FIG4 is an absorption spectrum of the ZnPc/EP@ _SiO2 microspheres prepared in Example 2 after UV aging at different times;

Figure 5 is an EDS spectrum of the ZnPc/EP@ _SiO2 microspheres prepared in Example 3; (a) is an electron image of the microspheres; (b) is an element spectrum of C, O, and Si; (c) is an EDS layered image; and (d) is an elemental surface total spectrum;

Figure 6 is the _{thermogravimetric} analysis graph of ZnPc/EP and ZnPc/EP@SiO2 prepared in Example 3.

DETAILED DESCRIPTION

In order to better understand the present invention, the present invention is described in detail with reference to the following examples, but the present invention is not limited to the following examples.

Example 1

1. The organic dye selected is commercially available ZnPc. Accurately weigh 0.15g ZnPc and dissolve it in 10g MXDA. Then add 0.15g hydrotalcite, 0.15g nano magnesium silicide with a size distribution of 20-50nm and 0.15g TEMP respectively. Ultrasonic dispersion is uniform and then used. Add 5g emulsifier OP-10 to 100ml deionized water, stir evenly at 80℃, add 5g epoxy resin monomer DGEBA, place it in a homogenizer and emulsify for 10min to form an oil-in-water emulsion, and continue to stir in a water bath at 80℃. Add 1.0g of the above-prepared curing agent MXDA containing ZnPc to the emulsified system, and cure it at 80℃ for 3h to obtain epoxy resin microspheres ZnPc/EP containing ZnPc dye. The average particle size of the prepared ZnPc/Ep microspheres is 350μm.

2. Add the prepared ZnPc/EP microspheres to a round-bottom flask, then add 3ml of deionized water, 3.6ml of ammonia water, and 60ml of ethanol, and keep the water bath at 60°C. Dissolve 1g of TEOS in 20ml of anhydrous ethanol, then add 50mg of TiO ₂ , and add it dropwise to the above solution after ultrasonic dispersion. Stir and react for 6h in a constant temperature water bath at 60°C to obtain a ZnPc/EP@SiO ₂ /TiO ₂ sample. Combined with thermogravimetric analysis and SEM images, the shell thickness is about 20nm, and the mass ratio of SiO ₂ to the ultraviolet shielding material TiO ₂ is 1:0.1.

Example 2

1. The organic dye selected is commercially available ZnPc. Accurately weigh 0.05g ZnPc and dissolve it in 10g MXDA. Then add 0.15g montmorillonite, 0.15g nano magnesium silicide with a size distribution of 20-50nm and 0.15g DPBF respectively. Ultrasonic dispersion is uniform and then used. Add 4g emulsifier OP-10 to 100ml deionized water, stir evenly at 85℃, add 3g epoxy resin monomer DGEBA, place it in a homogenizer and emulsify for 10min to form an oil-in-water emulsion, and continue to stir in a water bath at 85℃. Add 0.6g of the above-prepared curing agent MXDA containing ZnPc to the emulsified system, and cure at 85℃ for 2h to obtain epoxy resin microspheres ZnPc/EP containing ZnPc dye.

2. Add the prepared ZnPc/EP microspheres to a round-bottom flask, then add 3ml of deionized water, 3.6ml of ammonia water, and 60ml of ethanol, and keep the water bath at 60°C. Dissolve 0.5g of TEOS in 20ml of anhydrous ethanol, then add 45mg of TiO ₂ , and add dropwise to the above solution after ultrasonic dispersion. Stir and react for 6h in a constant temperature water bath at 60°C to obtain a ZnPc/EP@SiO ₂ /TiO ₂ sample. Combined with thermogravimetric analysis and SEM images, the shell thickness is about 12nm, and the mass ratio of SiO ₂ to the ultraviolet shielding material TiO ₂ is 1:0.08.

Figures 1 and 2 are SEM and FESEM images of ZnPc/EP@ _SiO2 prepared in this embodiment. It can be seen from the figures that the size of the prepared microspheres is approximately 300 to 500 μm, and the FESEM images show that the surface of the microspheres is wrapped with a dense _SiO2 layer to form microspheres with a core-shell structure.

Figures 3 and 4 show the absorption spectra of the ZnPc/EP sample and ZnPc/EP@ _SiO2 sample prepared in this example during ultraviolet aging. As shown in the figure, the zinc phthalocyanine dye has a characteristic absorption peak in the 600-700nm band. As the aging time increases, the absorption peak gradually weakens, and the spectrum of the microspheres wrapped with the _SiO2 / _TiO2 composite shell layer decays significantly more slowly, and the photostability is better than that of the unwrapped ZnPc/EP microspheres.

Example 3

1. The organic dye selected is commercially available ZnPc. Accurately weigh 0.24g ZnPc and dissolve it in 10g DETA. Then add 0.2g hydrotalcite and 0.2g nano magnesium silicide with a size distribution of 20-50nm respectively. Ultrasonic dispersion is uniform and then used. 7g emulsifier OP-10 is added to 100ml deionized water. After stirring at 70℃, 8g epoxy resin monomer DGEBA is added and placed in a homogenizer for emulsification for 10min to form an oil-in-water emulsion. Continue to stir in a water bath at 70℃. 1.6g of the above-prepared curing agent DETA containing ZnPc is added to the emulsification system and cured at 70℃ for 5h to obtain epoxy resin microspheres ZnPc/EP containing ZnPc dye. The average particle size of the prepared ZnPc/Ep microspheres is 415μm.

2. Add the prepared ZnPc/EP microspheres to a round-bottom flask, then add 3ml of deionized water, 3.6ml of ammonia water, and 60ml of ethanol, and keep the water bath at 60°C. Dissolve 2g of TEOS in 20ml of anhydrous ethanol, add dropwise to the above solution, and stir the reaction for 6h in a constant temperature water bath at 60°C to obtain a ZnPc/EP@ _SiO2 sample. Combined with thermogravimetric analysis and SEM images, the shell thickness is about 20nm. The mass ratio of _SiO2 to the ultraviolet shielding material _TiO2 is 1:0.08.

FIG5 is an EDS spectrum of the ZnPc/EP@SiO2 _microspheres prepared in this embodiment. In the figure, it can be seen that the Si element is evenly distributed on the surface of the microspheres, and the surface concentration of Si is 0.79% of the mass of the resin microspheres, proving that the surface of the microspheres is coated with _SiO2 .

FIG6 is a thermogravimetric analysis diagram of ZnPc/EP and ZnPC/EP@SiO ₂ microspheres prepared in this example. From the mass difference of the final product, it can be seen that the SiO ₂ content is approximately 0.9% of the mass of the resin microspheres.

Example 4

1. Weigh 0.15g Chl and dissolve it in 10g TETA, then add 0.8g nano magnesium silicide with a size distribution of 20-50nm, and disperse it evenly by ultrasonic dispersion for use. Add 5g emulsifier EL-40 to 100ml deionized water, stir evenly at 80℃, add 5g epoxy resin monomer DGEBA, place it in a homogenizer and emulsify it for 10min to form an oil-in-water emulsion, and continue to stir in a water bath at 80℃. Add 0.5g of the above-prepared curing agent TETA containing Chl to the emulsified system, and cure it at 80℃ for 3h to obtain epoxy resin microspheres Chl/EP containing Chl dye. The average particle size of the prepared Chl/Ep microspheres is 220μm.

2. Add the prepared Chl/EP microspheres to a round-bottom flask, then add 3ml of deionized water, 3.6ml of ammonia water, and 60ml of ethanol, and keep it in a water bath at 60°C. Dissolve 1g of TEOS in 20ml of anhydrous ethanol, then add 25mg of ZnO, and add it dropwise to the above solution after ultrasonic dispersion. Stir and react for 6h in a constant temperature water bath at 60°C to obtain a Chl/EP@SiO ₂ /ZnO sample. Combined with thermogravimetric analysis and SEM images, the shell thickness is about 16nm, and the mass ratio of SiO ₂ to the ultraviolet shielding material ZnO is 1:0.06.

Example 5

1. Weigh 0.05g Chl and dissolve it in 10g MXDA, then add 0.3g magnesium silicide with a size distribution of 20-50nm and 0.1g ABDA respectively, and disperse them evenly by ultrasonication for use. Add 4g emulsifier OP-10 to 100ml deionized water, stir evenly at 85℃, add 3g epoxy resin monomer DGEBA, place it in a homogenizer and emulsify for 10min to form an oil-in-water emulsion, and continue to stir in a water bath at 85℃. Add 0.6g of the above-prepared curing agent MXDA containing Chl to the emulsified system, and cure it at 85℃ for 2h to obtain epoxy resin microspheres Chl/EP containing Chl dye. The average particle size of the prepared Chl/Ep microspheres is 250μm.

2. Add the prepared Chl/EP microspheres to a round-bottom flask, then add 3ml of deionized water, 3.6ml of ammonia water, and 60ml of ethanol, and keep the water bath at 60°C. Dissolve 0.6g of TEOS in 20ml of anhydrous ethanol, then add 24mg of ZnO, and add dropwise to the above solution after ultrasonic dispersion. Stir and react for 6h in a constant temperature water bath at 60°C to obtain the Chl/EP@SiO ₂ /ZnO sample. Combined with thermogravimetric analysis and SEM images, the shell thickness is about 28nm, and the mass ratio of SiO ₂ to the ultraviolet shielding material TiO ₂ is 1:0.08.

Example 6

1. Weigh 0.24g Chl and dissolve it in 10g MXDA, then add 0.2g montmorillonite and 0.2g TEMP respectively, disperse evenly by ultrasonication and set aside. Add 7g emulsifier Tween-80 to 100ml deionized water, stir evenly at 70℃, add 8g epoxy resin monomer DGEBA, place in a homogenizer and emulsify for 10min to form an oil-in-water emulsion, and continue to stir in a water bath at 70℃. Add 1.6g of the above-prepared curing agent MXDA containing Chl to the emulsified system, and cure at 70℃ for 5h to obtain epoxy resin microspheres Chl/EP containing Chl dye. The average particle size of the prepared ZnPc/Ep microspheres is 325μm.

2. Add the prepared Chl/EP microspheres to a round-bottom flask, then add 3ml of deionized water, 3.6ml of ammonia water, and 60ml of ethanol, and keep the water bath at 60°C. Dissolve 1.2g of TEOS in 20ml of anhydrous ethanol, then add 20mg of ZnO, and add it dropwise to the above solution after ultrasonic dispersion. Stir and react for 6h in a constant temperature water bath at 60°C to obtain the Chl/EP@SiO ₂ /TiO ₂ sample. Combined with thermogravimetric analysis and SEM images, the shell thickness is about 13nm, and the mass ratio of SiO ₂ to the ultraviolet shielding material TiO ₂ is 1:0.5.

Table 1 shows the light protection rate of Examples 1 to 6 compared with pure dye after aging for 6h and 12h. The calculation method is that the difference in the degradation rate of the dye at this time point is the light protection rate of the sample in the example for the dye. It can be concluded from the data in the table that the oxygen-deficient microspheres with a UV shielding shell structure have a significant improvement in the light stability of the dye, and the highest light protection rate can reach 31.9% within 12h of light aging.

Table 1

Claims (5)

1. An oxygen-deficient microsphere with an ultraviolet shielding shell structure, characterized in that the oxygen-deficient microsphere is composed of a shell and an inner core; wherein the shell of the oxygen-deficient microsphere is composed of _SiO2 and an ultraviolet shielding functional substance, the mass ratio of which is 1:(0.05-0.1), and the shell thickness is 10-30 nm; the inner core of the oxygen-deficient microsphere is composed of a resin matrix, an oxygen-deficient functional filler and a dye molecule, and the inner core diameter is 200-500 μm; the mass of the dye molecule is 0.1-0.5% of the mass of the resin matrix; the mass of the oxygen-deficient functional filler is 0.1-1% of the mass of the resin matrix; wherein the ultraviolet shielding functional substance is any one of nano- _TiO2 or nano-ZnO or a combination of the two; the resin matrix is epoxy resin; the oxygen-deficient functional filler is composed of one or more of an oxygen inhibitor, an oxygen consuming agent or a singlet oxygen scavenger; the dye molecule is one of zinc phthalocyanine, chlorophyll, meta-tetraphenylsulfonate porphyrin zinc or tetraphenylporphyrin magnesium. 2. The oxygen-deficient microspheres according to claim 1, characterized in that the particle size of the ultraviolet shielding functional substance is 20 to 50 nm. 3. The oxygen-deficient microspheres according to claim 1 are characterized in that the oxygen inhibitor is a two-dimensional nanomaterial of montmorillonite or hydrotalcite; the oxygen consuming agent is nano-magnesium silicide, and the particle size of the nano-magnesium silicide is 20 to 50 nm; the singlet oxygen scavenger is one or more of 2,2,6,6-tetramethylpiperidinamine, 1,3-diphenylisobenzofuran or 9,10-anthracenediyl-bis(methylene)dimalonic acid. 4. A method for preparing the hypoxic microspheres as claimed in claim 1, wherein the specific steps are as follows: (1) Adding dye and hypoxic functional filler to curing agent, ultrasonically dispersing and setting aside; (2) adding an emulsifier and a resin prepolymer into water to uniformly emulsify, adding the curing agent containing a dye and an oxygen-deficient functional substance prepared in step (1) into the emulsion system, and performing thermal curing in a water bath at 75 to 85° C. to obtain an oxygen-deficient microsphere core containing an organic dye; (3) The ultraviolet shielding functional substance is uniformly dispersed in the silicon source, and the oxygen-deficient microsphere core prepared in step (2) is added and hydrolyzed and condensed on the surface to obtain the oxygen-deficient microsphere having a _SiO2 oxygen-deficient microsphere shell layer doped with the ultraviolet shielding functional substance. 5. The method according to claim 4, characterized in that the emulsifier is one of OP-10, EL-40 or Tween-80; the amount of the emulsifier is 4-7% of the mass of water; the resin prepolymer is 2,2-bis(4-epoxypropoxyphenyl)propane, and the amount is 3-8% of the mass of water; the curing agent is one of m-phenylenediamine, diethylenetriamine or triethylenetetramine; the silicon source is one of tetraethyl orthosilicate or methyl orthosilicate, and the mass ratio of the silicon source to the resin matrix is 1:(3-7); the amount of the ultraviolet shielding functional substance is 0.1-0.5% of the mass of the resin matrix.

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