A double-layer radiation shielding paper for suppressing lead leakage and a method for manufacturing the same

Abstract

The present application relates to the technical field of shielding material preparation, and particularly relates to a double-layer radiation shielding paper for inhibiting lead leakage and a preparation method thereof, which comprises the following steps: S1, respectively preparing ANF / DMSO solution and CsPbBr3 precursor solution; S2, preparing ANF@CsPbBr3 coaxial fiber with the outer layer being ANF / DMSO solution and the inner layer being CsPbBr3 precursor solution by using wet coaxial spinning, and then performing fiber shortening to obtain ANF@CsPbBr3 coaxial short fiber; S3, preparing ANF ethanol dispersion liquid by using ANF / DMSO solution, and adding ANF@CsPbBr3 coaxial short fiber into the ANF ethanol dispersion liquid in batches and equally, and then performing stirring, vacuum filtration and vacuum drying to obtain the radiation shielding paper. The coaxial fiber with the inner core being all-inorganic metal halide perovskite CsPbBr3 and the outer shell being aramid nanofiber ANF is prepared by using coaxial wet spinning and in-situ synthesis, and then the radiation shielding paper with the double-layer effect of inhibiting lead leakage is prepared by wet papermaking and compounding with protonated ANF.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of shielding material preparation, in particular to a double-layer radiation shielding paper for inhibiting lead leakage and a preparation method thereof. BACKGROUND

[0002] X-rays are a type of high-energy electromagnetic radiation with a short wavelength and high energy. However, due to the high energy and ionizing effect of X-rays, excessive exposure can pose a risk to human health. Therefore, safe use of X-ray technology requires strict operation and appropriate protective measures to minimize radiation hazards.

[0003] X-ray shielding materials are materials designed to block X-ray radiation and are widely used in medical diagnosis, industrial detection, and security checks. These materials can absorb, scatter, and isolate X-rays to reduce the radiation dose received by humans and equipment. However, there are some problems affecting the performance and application of X-ray shielding materials. Existing X-ray shielding materials may be too heavy and require a large thickness in some cases. This poses limitations for certain application scenarios, such as portable devices or narrow spaces.

[0004] Currently, the most widely used material is lead. Traditional X-ray shielding materials often use materials containing lead, such as lead plates or lead glass. However, lead is a toxic substance, and long-term exposure or inhalation of lead can have negative effects on human health, including damage to the nervous system, kidney problems, and reproductive system disorders. In addition to lead, some X-ray shielding materials may contain other toxic metals, such as cadmium, mercury, and antimony. These metals also have potential toxicity and can cause harm to human health. Therefore, some researchers have chosen less toxic elements as the main absorption elements for X-ray attenuation. Li Hao et al. from Sichuan University prepared a new type of wearable X-ray protection composite material using natural leather as the base material and CsI as the X-ray shielding filler. The shielding efficiency of this material for low-energy X-rays can reach more than 95%, and for medium-energy X-rays, it can reach more than 85%. Zhao Jiao et al. from Southwest University of Science and Technology prepared a modified nano Bi2O3 / Eu2O3 / EPVC-based X-ray shielding material, which also has good shielding effect. However, since heavy metal elements are indispensable for X-ray shielding materials, heavy metal elements can cause some negative effects on the human body. The Bi element, which is less toxic, is also limited in its application due to its high cost. Therefore, replacing less toxic elements for X-ray shielding does not fundamentally solve the problem.

[0005] Therefore, the current X-ray shielding materials have strong toxicity, are heavy, have poor flexibility, are not breathable, are expensive, and other factors limit their application, so it is crucial to develop a new generation of X-ray shielding flexible materials. SUMMARY

[0006] In view of the problems of strong toxicity and poor flexibility of X-ray shielding materials in the prior art, the application provides a double-layer radiation shielding paper capable of inhibiting lead leakage and a preparation method thereof.

[0007] The application is realized through the following technical scheme:

[0008] The preparation method of the double-layer radiation shielding paper capable of inhibiting lead leakage comprises the following steps:

[0009] S1, respectively preparing an ANF / DMSO solution and a CsPbBr3 precursor solution;

[0010] S2, preparing an ANF@CsPbBr3 coaxial fiber with an outer layer of the ANF / DMSO solution and an inner layer of the CsPbBr3 precursor solution by using a wet coaxial spinning method, and then performing fiber shortening to obtain an ANF@CsPbBr3 short-cut fiber;

[0011] S3, preparing an ANF ethanol dispersion solution by using the ANF / DMSO solution, and adding the ANF@CsPbBr3 short-cut fiber into the ANF ethanol dispersion solution in batches and in equal amounts, and then performing stirring, vacuum filtration and vacuum drying to obtain the radiation shielding paper.

[0012] Preferably, in S1, the preparation process of the ANF / DMSO solution is as follows: potassium hydroxide powder is dissolved in deionized water, and then dimethyl sulfoxide (DMSO) solution and para-aramid short-cut fibers (PPTA) are sequentially added, and the ANF / DMSO solution is prepared by mechanical stirring.

[0013] Preferably, the concentration of the ANF / DMSO solution is 10-25 mg / ml.

[0014] Preferably, the preparation step of the CsPbBr3 precursor solution is as follows: lead bromide and cesium bromide with equal proportion of molar mass are dissolved in a DMSO solution, and the CsPbBr3 precursor solution is obtained after stirring at room temperature.

[0015] Preferably, the concentration of the CsPbBr3 precursor solution is 0.25-0.5 mmol / ml.

[0016] Preferably, in S2, when the coaxial spinning is performed, the outer layer solution is extruded into a coagulation bath at a rate of 1.2-1.8 mm / min, the inner layer solution is extruded into the coagulation bath at a rate of 0.6-0.9 mm / min, and the coagulation bath is anhydrous ethanol solution.

[0017] Preferably, in S2, the length of the short-cut fiber is 5-7 mm.

[0018] Preferably, in S3, the volume ratio of ANF / DMSO solution to ethanol solution is 1:(20~50).

[0019] Preferably, in S3, the quantitative content of ANF@CsPbBr3 coaxial short-cut fibers is 0.04~0.08 g / cm³. 2 The mass ratio of ANF in the coaxial short-cut fibers of ANF@CsPbBr3 to ANF in the ANF ethanol dispersion is (20~100):1.

[0020] A radiation shielding paper prepared by the method described above for preparing a double-layer radiation shielding paper to suppress lead leakage.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] This invention discloses a method for preparing a double-layer radiation shielding paper that inhibits lead leakage. Coaxial fibers with a core of all-inorganic metal halide perovskite (CsPbBr3) and a shell of aramid nanofibers (ANF) are prepared through coaxial wet spinning and in-situ synthesis. These fibers are then combined with protonated ANF via wet papermaking to prepare a radiation shielding paper with a double-layer lead leakage inhibition effect. The prepared radiation shielding paper is lightweight, flexible, and possesses high X-ray shielding efficiency.

[0023] ANF@CsPbBr3 coaxial fibers, obtained through coaxial spinning, possess a core-shell structure. ANF, as a dense shell material, provides the first layer of lead leakage inhibition. Subsequently, ANF@CsPbBr3 coaxial chopped fibers are further compounded with ANF, and wet-processed into radiation shielding paper. At this stage, ANF further encapsulates the chopped fibers, providing a second layer of lead leakage inhibition. This dual-layer lead leakage inhibition plays a crucial role in human protection. Furthermore, in-situ synthesis of CsPbBr3 within the coaxial fibers improves the uniformity of CsPbBr3 within the fiber. CsPbBr3 has a larger effective atomic number, and the K-shell electron absorption edge of Cs (36.0 keV) can compensate for the weak absorption region of Pb (40~80 keV), resulting in a much lower density than lead plates while exhibiting a larger mass decay coefficient (μm). Attached Figure Description

[0024] Figure 1 This is a schematic flowchart of the preparation method of the present invention;

[0025] Figure 2 This is a SEM image of the coaxial short-cut fiber cross-section of ANF@CsPbBr3 in Embodiment 3 of the present invention;

[0026] Figure 3 This is a SEM image of the coaxial short-cut fiber shell of ANF@CsPbBr3 in Embodiment 3 of the present invention;

[0027] Figure 4 SEM image of the cross section of the ANF@ CsPbBr3 radiation shielding paper in Example 3 of the present application;

[0028] Figure 5 SEM image of the surface of the ANF@ CsPbBr3 radiation shielding paper in Example 3 of the present application;

[0029] Figure 6 X-ray shielding performance data graph of the ANF@ CsPbBr3 composite paper in Example 3 of the present application. DETAILED DESCRIPTION

[0030] The present application will be further described in conjunction with specific examples, which are an explanation of the present application rather than a limitation.

[0031] The present application discloses a preparation method of a double-layer radiation shielding paper for inhibiting lead leakage, referring to Figure 1 , comprising the following steps:

[0032] S1, respectively preparing an ANF / DMSO solution and a CsPbBr3 precursor solution.

[0033] The preparation process of the ANF / DMSO solution is as follows: 1.5-2.5 g of potassium hydroxide powder is dissolved in 0-5 ml of deionized water, and then 250 ml of dimethyl sulfoxide (DMSO) solution and 2.5-6.25 g of para-aramid short-cut fibers (PPTA) are sequentially added, and an ANF / DMSO solution with a concentration of 10-25 mg / ml is prepared by mechanical stirring for 12-168 h.

[0034] The preparation steps of the CsPbBr3 precursor solution are as follows: equal proportions of lead bromide and cesium bromide are dissolved in a DMSO solution, and after stirring at room temperature for 30-60 min, a CsPbBr3 precursor solution with a concentration of 0.25-0.5 mmol / ml is obtained.

[0035] S2, an ANF@ CsPbBr3 coaxial fiber with an outer layer of the ANF / DMSO solution and an inner layer of the CsPbBr3 precursor solution is prepared by wet coaxial spinning, and then the fiber is short-cut to obtain 5-7 mm of ANF@ CsPbBr3 coaxial short-cut fibers.

[0036] Wherein, when coaxial spinning, the outer layer is ANF / DMSO solution, the inner layer is CsPbBr3 precursor solution, and the two solutions pass through the coaxial needle (inner diameter 22G, outer diameter 17G) into the coagulation bath in turn, and then stay in the coagulation bath, and then pass through the stretching and drying to obtain the ANF@CsPbBr3 coaxial fiber. The outer layer solution is extruded into the coagulation bath at a rate of 1.2-1.8 mm / min, and the inner layer solution is extruded into the coagulation bath at a rate of 0.6-0.9 mm / min, and the coagulation bath is anhydrous ethanol solution.

[0037] S3, ANF ethanol dispersion liquid is prepared by using ANF / DMSO solution, and the ANF@CsPbBr3 coaxial chopped fiber is added into the ANF ethanol dispersion liquid in batches, and then stirred, vacuum filtered and vacuum dried to obtain the radiation shielding paper.

[0038] Wherein, the ANF / DMSO solution is poured into ethanol, and the volume ratio of the ANF / DMSO solution to the ethanol solution is 1:(20-50), and the ANF is fully protonated by mechanical stirring for 5-10 min to obtain the ANF ethanol dispersion liquid.

[0039] The mass of the ANF@CsPbBr3 coaxial chopped fiber is 0.04-0.08 g / cm 2 , and the mass ratio of the ANF@CsPbBr3 coaxial chopped fiber to the ANF in the ANF ethanol dispersion liquid is (20-100):1. When mixing, the ANF@CsPbBr3 coaxial chopped fiber and the ANF ethanol dispersion liquid are mixed in 3-5 batches, and the mechanical stirring time is 5-10 min. When vacuum filtering, the vacuum degree is 0.08 MPa; when vacuum drying, the temperature is 85-105 ℃, and the time is 5-10 min.

[0040] Example 1

[0041] Step 1, ANF / DMSO solution and CsPbBr3 precursor solution are prepared respectively, and the preparation process of the ANF / DMSO solution is as follows: 2 g of potassium hydroxide powder is dissolved in 5 ml of deionized water, and then 250 ml of DMSO solution and 3.75 g of PPTA are added in turn, and the ANF / DMSO solution with a concentration of 15 mg / ml is prepared by mechanical stirring for 12 h. The preparation steps of the CsPbBr3 precursor solution are as follows: lead bromide and cesium bromide with equal proportion of molar mass are dissolved in DMSO solution, and mechanical stirring is carried out at room temperature for 30 min to obtain the CsPbBr3 precursor solution with a concentration of 0.5 mmol / ml.

[0042] Step 2, wet spinning was adopted, the outer layer was ANF / DMSO solution, and the inner layer was CsPbBr3 precursor solution, which passed through coaxial needles with inner diameter of 22G and outer diameter of 17G in sequence, the outer layer solution was extruded into anhydrous ethanol coagulation bath at a rate of 1.8 mm / min, the inner layer solution was extruded into anhydrous ethanol coagulation bath at a rate of 0.9 mm / min, after staying in the coagulation bath for 7 min, the ANF@CsPbBr3 coaxial fiber was obtained by stretching at a stretching ratio of 1.1 and drying at room temperature, and then the fiber was chopped to obtain ANF@CsPbBr3 coaxial chopped fiber with a length of 5-7 mm.

[0043] Step 3, the ANF / DMSO solution was poured into ethanol according to the volume ratio of ANF / DMSO solution to ethanol of 1:50, and mechanical stirring was adopted for 10 min to fully protonate the ANF to obtain ANF ethanol dispersion;

[0044] The ANF@CsPbBr3 coaxial chopped fiber with a dosage of 0.08 g / cm 2 The ANF@CsPbBr3 coaxial chopped fiber was added to the ANF ethanol dispersion according to the mass ratio of ANF@CsPbBr3 coaxial chopped fiber to ANF in the ANF ethanol dispersion of 20:1, mechanical stirring was adopted for 10 min, and then vacuum assisted filtration was carried out, and then the radiation shielding paper was prepared by drying at a vacuum degree of 0.08 MPa and a temperature of 105 ℃ for 5 min.

[0045] Example 2

[0046] Step 1, ANF / DMSO solution and CsPbBr3 precursor solution were prepared respectively, the preparation process of ANF / DMSO solution was as follows: 2.5 g of potassium hydroxide powder was dissolved in 5 ml of deionized water, and then 250 ml of DMSO solution and 5 g of PPTA were added in sequence, and ANF / DMSO solution with a concentration of 20 mg / ml was prepared by mechanical stirring for 24 h. The preparation steps of CsPbBr3 precursor solution were as follows: lead bromide and cesium bromide with equal proportion of molar mass were dissolved in DMSO solution, and mechanical stirring was carried out at room temperature for 60 min to obtain CsPbBr3 precursor solution with a concentration of 0.5 mmol / ml;

[0047] Step 2, wet spinning was adopted, the outer layer was ANF / DMSO solution, and the inner layer was CsPbBr3 precursor solution, which passed through coaxial needles with inner diameter of 22G and outer diameter of 17G in sequence, the outer layer solution was extruded into anhydrous ethanol coagulation bath at a rate of 1.8 mm / min, the inner layer solution was extruded into anhydrous ethanol coagulation bath at a rate of 0.9 mm / min, after staying in the coagulation bath for 7 min, the ANF@CsPbBr3 coaxial fiber was obtained by stretching at a stretching ratio of 1.1 and drying at room temperature, and then the fiber was chopped to obtain ANF@CsPbBr3 coaxial chopped fiber with a length of 5-7 mm.

[0048] Step 3, the ANF / DMSO solution was poured into ethanol according to the volume ratio of ANF / DMSO solution to ethanol of 1:50, and mechanical stirring was adopted for 10 min to fully protonate the ANF to obtain ANF ethanol dispersion;

[0049] The ANF@CsPbBr3 coaxial chopped fiber with a mass of 0.08 g / cm 2 was added to the ANF ethanol dispersion in 5 batches according to the actual mass ratio of ANF@CsPbBr3 coaxial chopped fiber to ANF in the ANF ethanol dispersion of 20:1, and mechanical stirring was adopted for 10 min to fully mix and uniformly mix, and then vacuum assisted filtration was carried out, and then the radiation shielding paper was prepared by drying at a vacuum degree of 0.08 MPa and a temperature of 85 ℃ for 5 min.

[0050] Example 3

[0051] Step 1, ANF / DMSO solution and CsPbBr3 precursor solution were prepared respectively, the preparation process of ANF / DMSO solution was as follows: 2.5 g of potassium hydroxide powder was dissolved in 5 ml of deionized water, and then 250 ml of DMSO solution and 6.25 g of PPTA were added in sequence, and ANF / DMSO solution with a concentration of 25 mg / ml was prepared by mechanical stirring for 24 h. The preparation steps of CsPbBr3 precursor solution were as follows: lead bromide and cesium bromide with equal proportion of molar mass were dissolved in DMSO solution, and mechanical stirring was carried out at room temperature for 60 min to obtain CsPbBr3 precursor solution with a concentration of 0.5 mmol / ml;

[0052] Step 2, wet spinning was adopted, the outer layer was ANF / DMSO solution, the inner layer was CsPbBr3 precursor solution, the coaxial needle with inner diameter of 22G and outer diameter of 17G was used in sequence, the outer layer solution was extruded into anhydrous ethanol coagulation bath at a rate of 1.8 mm / min, the inner layer solution was extruded into anhydrous ethanol coagulation bath at a rate of 0.9 mm / min, after staying in the coagulation bath for 7 min, the coaxial fiber was obtained by stretching at a stretching ratio of 1.1, drying at room temperature, and then the fiber was chopped to obtain 5-7 mm ANF@CsPbBr3 coaxial chopped fiber.

[0053] Step 3, the ANF / DMSO solution was poured into ethanol according to the volume ratio of ANF / DMSO solution to ethanol of 1:50, and mechanical stirring was adopted for 10 min to fully protonate the ANF to obtain ANF ethanol dispersion;

[0054] The ANF@CsPbBr3 coaxial chopped fiber with a dosage of 0.08 g / cm 2 was added into the ANF ethanol dispersion according to the actual mass ratio of ANF@CsPbBr3 coaxial chopped fiber to ANF in the ANF ethanol dispersion of 20:1, mechanical stirring was adopted for 10 min, and then vacuum assisted filtration was carried out, and then the radiation shielding paper was prepared by drying at a vacuum degree of 0.08 MPa and a temperature of 85 ℃ for 10 min.

[0055] The related tests of the radiation shielding paper prepared in Example 3 are shown in Figure 2 , 3 It can be seen that the ANF@CsPbBr3 coaxial chopped fiber has a clear core-shell structure, and since the CsPbBr3 is synthesized in situ in the fiber, when the spinning solution enters the coagulation bath, the Cs + , Br + , Pb 2+ three ions in the CsPbBr3 precursor solution will diffuse outward, and the anhydrous ethanol coagulation bath will diffuse inward, since the solubility of CsPbBr3 in anhydrous ethanol is low, the Cs + , Br + , Pb 2+ three ions will precipitate in the form of CsPbBr3 crystal when they meet the coagulation bath, forming a special coaxial structure with shell layer 1 being ANF, shell layer 2 being a mixed shell layer of ANF and CsPbBr3, and core being CsPbBr3 particles. This structure provides the first line of defense against lead leakage.

[0056] Figure 4 The cross section of the radiation shielding paper in this embodiment is shown, in which the black lines represent the two lines of defense against lead leakage. Figure 6The shielding efficiency of the display radiation shielding paper can reach more than 90% and the mass attenuation coefficient can reach more than 45 cm 2 / g when the tube voltage is 20-70 kV, and the mass attenuation coefficient decreases with the increase of the tube voltage, because the higher the tube voltage, the stronger the penetration of X-rays, and the more difficult the shielding.

[0057] Example 4

[0058] Step 1, respectively prepare ANF / DMSO solution and CsPbBr3 precursor solution, the preparation process of ANF / DMSO solution is as follows: take 2.5 g of potassium hydroxide powder and dissolve it in 0 ml of deionized water, then add 250 ml of DMSO solution and 6.25 g of PPTA in sequence, and prepare ANF / DMSO solution with a concentration of 25 mg / ml by mechanical stirring for 168 h. The preparation steps of CsPbBr3 precursor solution are as follows: take lead bromide and cesium bromide with equal proportion of molar mass and dissolve them in DMSO solution, and obtain CsPbBr3 precursor solution with a concentration of 0.25 mmol / ml by mechanical stirring at room temperature for 30 min;

[0059] Step 2, adopt wet spinning, the outer layer is ANF / DMSO solution and the inner layer is CsPbBr3 precursor solution, pass through coaxial needles with an inner diameter of 22G and an outer diameter of 17G in sequence, extrude the outer layer solution into anhydrous ethanol coagulation bath at a rate of 1.8 mm / min, extrude the inner layer solution into anhydrous ethanol coagulation bath at a rate of 0.9 mm / min, stay in the coagulation bath for 7 min, then stretch at a stretching ratio of 1.0, dry at room temperature, and obtain ANF@ CsPbBr3 coaxial fiber, then perform fiber shortening to obtain ANF@ CsPbBr3 coaxial short-cut fiber with a length of 5-7 mm.

[0060] Step 3, pour the ANF / DMSO solution into ethanol at a volume ratio of ANF / DMSO solution to ethanol of 1:20, and mechanically stir for 5 min to fully protonate ANF, and obtain ANF ethanol dispersion;

[0061] Divide the ANF@ CsPbBr3 coaxial short-cut fiber with a mass of 0.08 g / cm 2 , add it to the ANF ethanol dispersion at an actual mass ratio of ANF@ CsPbBr3 coaxial short-cut fiber to ANF in the ANF ethanol dispersion of 100:1, mechanically stir for 5 min, fully mix and uniform, then perform vacuum-assisted suction filtration, and then dry at a vacuum degree of 0.08 MPa and a temperature of 105 ℃ for 5 min, and obtain radiation shielding paper.

[0062] Example 5

[0063] Step 1, respectively prepare ANF / DMSO solution and CsPbBr3 precursor solution, the preparation process of ANF / DMSO solution is as follows: take 2.5 g of potassium hydroxide powder and dissolve in 5 ml of deionized water, then add 250 ml of DMSO solution and 6.25 g of PPTA in turn, and prepare ANF / DMSO solution with a concentration of 25 mg / ml by mechanical stirring for 24 h. The preparation steps of CsPbBr3 precursor solution are as follows: take lead bromide and cesium bromide with equal proportion of molar mass and dissolve in DMSO solution, mechanically stir at room temperature for 60 min, and obtain CsPbBr3 precursor solution with a concentration of 0.5 mmol / ml;

[0064] Step 2, adopt wet spinning, the outer layer is ANF / DMSO solution, and the inner layer is CsPbBr3 precursor solution, pass through coaxial needles with an inner diameter of 22G and an outer diameter of 17G in turn, extrude the outer layer solution into anhydrous ethanol coagulation bath at a rate of 1.8 mm / min, extrude the inner layer solution into anhydrous ethanol coagulation bath at a rate of 0.6 mm / min, stay in the coagulation bath for 7 min, then stretch at a stretching ratio of 1.1, dry at room temperature, and obtain ANF@ CsPbBr3 coaxial fiber, then perform fiber shortening, and obtain ANF@ CsPbBr3 coaxial short-cut fiber with a length of 5-7 mm.

[0065] Step 3, pour the ANF / DMSO solution into ethanol at a volume ratio of ANF / DMSO solution to ethanol of 1:50, and mechanically stir for 10 min to fully protonate ANF, and obtain ANF ethanol dispersion;

[0066] Divide the 0.04 g / cm 2 of ANF@ CsPbBr3 coaxial short-cut fiber into 5 batches, and add to the ANF ethanol dispersion at an actual mass ratio of ANF@ CsPbBr3 coaxial short-cut fiber to ANF in the ANF ethanol dispersion of 100:1, mechanically stir for 5 min, fully mix uniformly, then perform vacuum assisted filtration, and then dry at a vacuum degree of 0.08 MPa and a temperature of 85 ℃ for 10 min, and obtain radiation shielding paper.

[0067] Example 6

[0068] Step 1, respectively prepare ANF / DMSO solution and CsPbBr3 precursor solution, the preparation process of ANF / DMSO solution is as follows: 2.5 g of potassium hydroxide powder is dissolved in 5 ml of deionized water, then 250 ml of DMSO solution and 6.25 g of PPTA are sequentially added, and a 25 mg / ml ANF / DMSO solution is prepared by mechanical stirring for 24 h. The preparation steps of the CsPbBr3 precursor solution are as follows: equal proportion of molar mass lead bromide and cesium bromide is dissolved in DMSO solution, and mechanical stirring is carried out at room temperature for 60 min to obtain a 0.5 mmol / ml CsPbBr3 precursor solution;

[0069] Step 2, wet spinning is adopted, the outer layer is ANF / DMSO solution, and the inner layer is CsPbBr3 precursor solution, which passes through coaxial needles with an inner diameter of 22G and an outer diameter of 17G in sequence, the outer layer solution is extruded into anhydrous ethanol coagulation bath at a rate of 1.2 mm / min, the inner layer solution is extruded into anhydrous ethanol coagulation bath at a rate of 0.9 mm / min, and after staying in the coagulation bath for 5 min, it is stretched by a stretching ratio of 1.1 and dried at room temperature to obtain ANF@ CsPbBr3 coaxial fiber, and then the fiber is chopped to obtain 5-7 mm ANF@ CsPbBr3 coaxial chopped fiber.

[0070] Step 3, pour the ANF / DMSO solution into ethanol at a volume ratio of ANF / DMSO solution to ethanol of 1:50, and mechanically stir for 10 min to fully protonate the ANF to obtain an ANF ethanol dispersion;

[0071] Divide the 0.08 g / cm 2 of ANF@ CsPbBr3 coaxial chopped fiber into 5 batches, and add it to the ANF ethanol dispersion at an actual mass ratio of ANF@ CsPbBr3 coaxial chopped fiber to ANF in the ANF ethanol dispersion of 20:1, mechanically stir for 10 min, fully mix and evenly distribute, then perform vacuum assisted filtration, and then dry at a vacuum degree of 0.08 MPa and a temperature of 85 DEG C for 10 min to prepare a radiation shielding paper.

[0072] The application also discloses a radiation shielding paper prepared by a preparation method of a double-layer radiation shielding paper for inhibiting lead leakage.

[0073] The application also discloses an application of the radiation shielding paper in medical diagnosis, industrial detection and safety inspection.

[0074] The above merely describes the preferred embodiments of the present application, and is not intended to limit the technical solutions of the present application in any way. Those skilled in the art should understand that, without departing from the spirit and principle of the present application, the technical solutions can also be modified and replaced in several simple ways, and these modifications and replacements also all belong to the protection scope covered by the claims.

Claims

1. A method for preparing a double-layer radiation shielding paper to suppress lead leakage, characterized in that, Comprising the following steps: S1, respectively preparing ANF / DMSO solution and CsPbBr3 precursor solution; S2, using wet coaxial spinning to prepare ANF@CsPbBr3 coaxial fiber with outer layer of ANF / DMSO solution and inner layer of CsPbBr3 precursor solution, and then performing fiber shortening to obtain ANF@CsPbBr3 coaxial short-cut fiber; During coaxial spinning, the outer layer solution is extruded into the coagulation bath at a rate of 1.2-1.8 mm / min, and the inner layer solution is extruded into the coagulation bath at a rate of 0.6-0.9 mm / min, and the coagulation bath is anhydrous ethanol solution; S3, using ANF / DMSO solution to prepare ANF ethanol dispersion, and adding ANF@CsPbBr3 coaxial short-cut fiber into the ANF ethanol dispersion in batches, and then stirring, vacuum filtration and vacuum drying to obtain radiation shielding paper.

2. The method for preparing double-layer radiation shielding paper to suppress lead leakage according to claim 1, characterized in that, In S1, the preparation process of ANF / DMSO solution is as follows: potassium hydroxide powder is dissolved in deionized water, then dimethyl sulfoxide solution and para-aramid short-cut fiber are added in sequence, and ANF / DMSO solution is prepared by mechanical stirring.

3. The method for preparing double-layer radiation shielding paper to suppress lead leakage according to claim 2, characterized in that, The concentration of ANF / DMSO solution is 10-25 mg / ml.

4. The method for preparing double-layer radiation shielding paper to suppress lead leakage according to claim 1, characterized in that, The preparation steps of CsPbBr3 precursor solution are as follows: lead bromide and cesium bromide with equal proportion of molar mass are dissolved in DMSO solution, and CsPbBr3 precursor solution is obtained after stirring at room temperature.

5. The method for preparing double-layer radiation shielding paper to suppress lead leakage according to claim 4, characterized in that, The concentration of CsPbBr3 precursor solution is 0.25-0.5 mmol / ml.

6. The method of claim 1, wherein the double-layered radiation shielding paper is prepared by the steps of: In S2, the length of the short-cut fiber is 5-7 mm.

7. The method for preparing double-layer radiation shielding paper to suppress lead leakage according to claim 1, characterized in that, In S3, the volume ratio of ANF / DMSO solution to ethanol solution is 1:(20-50).

8. The method of claim 1, wherein the double-layered radiation shielding paper is prepared by the steps of: The quantification of ANF@CsPbBr3 coaxial chopped fibers in S3 is 0.04-0.08 g / cm 2 The mass ratio of ANF@CsPbBr3 coaxial chopped fibers to ANF in the ANF ethanol dispersion is (20-100):

1.

9. A radiation shielding paper prepared by the method of any one of claims 1-8.

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