Radiation-proof flexible material and preparation method thereof

Abstract

This invention discloses a radiation-shielding flexible material and its preparation method, relating to the field of radiation-shielding flexible material technology. In preparing the radiation-shielding flexible material, the invention involves treating a protective powder with γ-chloropropyltriethoxysilane to obtain a pre-modified protective powder; reacting the pre-modified protective powder with a composite antibacterial agent to obtain a modified protective powder; reacting phenylphosphoyl dichloride sequentially with diethyl iminodiacetic acid, ethylenediamine, and benzothiazole-2-carboxaldehyde to obtain a phosphorus-nitrogen-sulfur flame retardant; mixing the modified protective powder, the phosphorus-nitrogen-sulfur flame retardant, and thermoplastic polyurethane, using N,N-dimethylformamide as a dispersant, to prepare a protective slurry; coating the protective slurry onto the surface of a fabric and drying to obtain the radiation-shielding flexible material. The radiation-shielding flexible material prepared by this invention can protect against radiation while also possessing excellent flame-retardant and antibacterial properties.

Description

Technical Field

[0001] This invention relates to the field of radiation-resistant flexible materials technology, specifically to a radiation-resistant functional flexible material and its preparation method. Background Technology

[0002] Gamma rays, due to their strong penetrating properties, have been widely used in various fields such as medicine, nuclear industry, food testing, and security inspection. However, long-term exposure to gamma rays can cause serious harm to human health, leading to problems such as autonomic nervous system dysfunction, hematopoietic damage, lens opacity, and reproductive disorders. Therefore, the development of gamma ray protection materials is of great practical significance.

[0003] Existing nuclear radiation protection materials are mainly divided into two categories: one is high-density metallic materials, represented by lead plates and tungsten blocks. These materials rely on their high atomic number and high density to attenuate radiation, but they have significant drawbacks: they are rigid and inflexible, making them unsuitable for human wear (such as protective aprons and gloves), curved equipment wrapping, and protection in confined spaces; heavy metals such as lead are toxic and can easily cause soil and water pollution throughout their entire life cycle, failing to meet environmental protection requirements; their high density leads to excessive loads on protective equipment, making them unsuitable for weight-sensitive scenarios such as aerospace. The other category is flexible composite protective materials, prepared by combining shielding particles such as bismuth oxide and gadolinium oxide with polymer matrices such as rubber and polyurethane. However, they still face technical bottlenecks: to achieve the protective effect, a high proportion of shielding powder needs to be added, leading to deterioration of the material's mechanical properties and making it prone to cracking and delamination; the shielding powder has poor compatibility with the polymer matrix, and it is prone to agglomeration during mixing, resulting in uneven protective performance.

[0004] On the other hand, with the diversification of application fields and environments for flexible composite protective materials, higher requirements are being placed on their antibacterial and flame-retardant capabilities. Therefore, developing a protective material that combines flexibility, lightweight, high protective efficiency, and antibacterial and flame-retardant capabilities has become key to overcoming existing technological bottlenecks. Summary of the Invention

[0005] The purpose of this invention is to provide a flexible material with radiation protection function and its preparation method, so as to solve the problems existing in the prior art.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: A radiation-protective flexible material is obtained by mixing modified protective powder, phosphorus-nitrogen-sulfur flame retardant, and thermoplastic polyurethane, using N,N-dimethylformamide as a dispersant to prepare a protective slurry; coating the protective slurry onto the surface of a fabric and drying it.

[0007] Furthermore, the modified protective powder is prepared by reacting pre-modified protective powder with a composite antibacterial agent.

[0008] Furthermore, the pre-modified protective powder is prepared by reacting protective powder with γ-chloropropyltriethoxysilane.

[0009] Furthermore, the composite antibacterial agent is obtained by chlorinating intermediate B with sodium hypochlorite.

[0010] Furthermore, intermediate B is prepared by reacting intermediate A with 4-dimethylaminobutyric acid.

[0011] Furthermore, intermediate A is prepared by reacting p-hydroxybenzaldehyde and iminodiacetamide.

[0012] Furthermore, the phosphorus-nitrogen-sulfur flame retardant is prepared by reacting product 2 with benzothiazole-2-carboxaldehyde.

[0013] Furthermore, product 2 is prepared by reacting product 1 with ethylenediamine.

[0014] Furthermore, product 1 is prepared by reacting phenylphosphodichloro and diethyl iminodiacetate.

[0015] Furthermore, the protective powder includes, but is not limited to, one or more of the following: gadolinium oxide powder, bismuth powder, tungsten oxide powder, rare earth element oxide powder (lanthanum, yttrium, cerium oxide, etc.), boride powder, and metal-organic framework-derived high atomic number metal oxide powder.

[0016] A method for preparing a radiation-shielding flexible material, the method comprising the following steps: (1) Sodium hypochlorite, deionized water and tert-butanol are mixed evenly in a mass ratio of 1:(2~3):(8~10) to prepare a chlorination-modified solution; intermediate B and chlorination-modified solution are mixed evenly in a mass ratio of 1:(10~12), stirred at room temperature for 4~6 hours, and evaporated under reduced pressure to obtain a composite antibacterial agent. (2) Mix the pre-modified protective powder and anhydrous ethanol at a mass ratio of 1:(20~30), sonicate for 20~30 min, add 3~5 times the mass of the pre-modified protective powder and 0.04~0.06 times the mass of the composite antibacterial agent, add potassium iodide, stir and react at 70~78℃ for 30~40 h under nitrogen protection, filter, wash with anhydrous ethanol 3~5 times, and vacuum dry at 60~70℃ for 20~22 h to obtain the modified protective powder; (3) Add product 2 and benzothiazole-2-carboxaldehyde to N,N-dimethylformamide at a molar ratio of 1:4, which is 8 to 10 times the mass of product 2. Stir and react at 50 to 60°C for 7 to 8 hours, and then vacuum dry at 80 to 90°C for 16 to 20 hours to obtain phosphorus-nitrogen-sulfur flame retardant. (4) Mix the modified protective powder, phosphorus-nitrogen-sulfur flame retardant and thermoplastic polyurethane, adjust the viscosity to 7~8 Pa·S with N,N-dimethylformamide, and defoam under vacuum to obtain a protective slurry; use a 100μm coating line to coat the protective slurry onto the fabric surface, dry at 70~80℃ for 10~20min, and vacuum dry at 40~50℃ for 60~80min to obtain a flexible material with radiation protection function.

[0017] Further, the preparation method of intermediate B in step (1) is as follows: intermediate A and 4-dimethylaminobutyric acid are added to dichloromethane at a molar ratio of 1:1, which is 8 to 10 times the mass of intermediate A. Palladium acetate is added at 0.01 to 0.02 times the mass of intermediate A, and potassium phosphate is added at 0.03 to 0.04 times the mass of intermediate A. The mixture is stirred and refluxed at 75 to 85°C for 60 to 70 minutes. After filtration, the filtrate is evaporated under reduced pressure to obtain intermediate B.

[0018] Further, the preparation method of intermediate A is as follows: p-hydroxybenzaldehyde and iminodiacetamide are added to a 37wt% hydrochloric acid aqueous solution at a molar ratio of 1:(1~1.1) to 8~10 times the mass of p-hydroxybenzaldehyde, stirred at room temperature for 22~26h, then ice water at 40~50 times the mass of p-hydroxybenzaldehyde is added, washed with deionized water until pH=5, filtered, and vacuum dried at 50~60℃ for 20~24h to obtain intermediate A.

[0019] Further, the preparation method of the pre-modified protective powder in step (2) is as follows: the protective powder, deionized water and anhydrous ethanol are mixed in a mass ratio of 1:(10~16):(60~80), ultrasonically dispersed for 1~2h, γ-chloropropyltriethoxysilane with a mass of 0.2~0.3 times that of the protective powder is added, the mixture is stirred at 60~70℃ for 5~6h, filtered, washed with anhydrous ethanol 3~5 times, and vacuum dried at 60~70℃ for 10~12h to obtain the pre-modified protective powder.

[0020] Further, the preparation method of product 2 in (3) is as follows: product 1 and tetrahydrofuran are mixed in a mass ratio of 1:6~8, and ethylenediamine of 6~8 times the molar amount of product 1 is added dropwise at a uniform rate within 30 min. The temperature is raised to 60~66℃ and stirred for 4~5 h. The product 2 is obtained by vacuum distillation. Further, the preparation method of product 1 is as follows: phenylphosphine dichloride, diethyl iminodiacetic acid, and triethylamine are added to chloroform at a molar ratio of 1:2:2, which is 8 to 10 times the mass of phenylphosphine dichloride. Then, 4-dimethylaminopyridine is added at a mass of 0.008 to 0.01 times the mass of phenylphosphine dichloride. The mixture is stirred and refluxed at 65 to 75°C for 20 to 24 hours, and then distilled under reduced pressure to obtain product 1.

[0021] Further, the dosage relationship of the modified protective powder, phosphorus-nitrogen-sulfur flame retardant and thermoplastic polyurethane in step (4) is as follows: by mass parts, take 40-50 parts of modified protective powder, 8-10 parts of phosphorus-nitrogen-sulfur flame retardant and 50-60 parts of thermoplastic polyurethane.

[0022] Furthermore, the radiation-resistant flexible material prepared in this application can be further cut and twisted into radiation-resistant yarn.

[0023] Further, the preparation process of the radiation-proof yarn is as follows: the radiation-proof flexible material prepared in step (4) is slit using a precision slitting device. During slitting, the slitting width is controlled to be 0.5~2mm, the slitting speed is adjusted to 5~10m / min, and the gap between the slitting blades is controlled to be 0.01~0.03mm. After slitting, the obtained protective narrow strip is fed into a twisting device. The twisting speed is set to 800~1200r / min, the twist is 20~50 twists / 10cm, and the tension of the narrow strip is kept stable during the twisting process. The tension is controlled to be 5~15N to obtain the radiation-proof yarn.

[0024] Furthermore, the radiation-proof yarn can be directly used to weave protective fabrics, make protective ropes, protective gloves and other products, or it can be blended with other fiber yarns.

[0025] The beneficial effects achieved by this invention are as follows: Firstly, intermediate A is prepared by reacting p-hydroxybenzaldehyde and iminodiacetamide. Intermediate A is then reacted with 4-dimethylaminobutyric acid to prepare intermediate B. Intermediate B contains both a tertiary amine structure and a haloamine precursor. The haloamine precursor in intermediate B is then chlorinated with sodium hypochlorite to obtain a composite antibacterial agent. The protective powder is treated with γ-chloropropyltriethoxysilane, resulting in the grafting of numerous chlorine atoms. This chlorine atom then undergoes a quaternization reaction with the composite antibacterial agent, grafting both haloamine antibacterial components and a quaternary ammonium salt structure onto the protective powder, thus exhibiting dual-activity antibacterial properties and endowing the material with excellent antibacterial capabilities. The protective powder can also provide radiation protection. Surface modification of the protective powder can improve its dispersibility and prevent agglomeration.

[0026] Secondly, product 1 was prepared by reacting phenylphosphine dichloride and diethyl iminodiacetic acid. Product 1 was then subjected to an ester exchange reaction with ethylenediamine to obtain product 2. The amino group on product 2 was subjected to a Schiff base reaction with the aldehyde group of benzothiazole-2-carboxaldehyde to obtain a phosphorus-nitrogen-sulfur flame retardant. This multi-element composite flame retardant has superior flame retardant ability compared with single-component flame retardants. At the same time, the study showed that the benzothiazole structure also has a certain antibacterial effect.

[0027] Thirdly, modified protective powder, phosphorus-nitrogen-sulfur flame retardant, and thermoplastic polyurethane are mixed and formulated with N,N-dimethylformamide to create a protective slurry. This slurry is then coated onto the surface of a fabric and dried to obtain a flexible material with radiation protection function. This flexible material can be used directly or slit and twisted into radiation-protective yarn. The radiation-protective yarn can be used directly to weave protective fabrics, make protective ropes, protective gloves, and other products. It can also be blended with other fiber yarns to meet different application needs. Attached Figure Description

[0028] Figure 1 A schematic diagram of the reaction process of the "composite antibacterial agent" in step (1) of the preparation method of radiation-resistant flexible material.

[0029] Figure 2 A schematic diagram of the reaction process of the "phosphorus-nitrogen-sulfur flame retardant" in step (3) of the preparation method of radiation-resistant flexible material.

[0030] Figure 3 This is an electron microscope image of the radiation-shielding yarn prepared in Example 1 of the present invention. Detailed Implementation

[0031] 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.

[0032] Raw material information: Preparation of protective powder: Gadolinium oxide powder and bismuth oxide powder are mixed at a mass ratio of 1:1 to obtain protective powder; wherein the particle diameter of both gadolinium oxide powder and bismuth oxide powder is 5μm.

[0033] Thermoplastic polyurethane: BASF 685A (Germany), Suzhou Huasulian Plastics Technology Co., Ltd.

[0034] Fabric: Polyester nonwoven fabric, weight 180g / m² 2 Jiangxi Haorui Industrial Materials Co., Ltd.

[0035] Example 1: A method for preparing a radiation-shielding flexible material includes the following preparation steps: (1) p-hydroxybenzaldehyde and iminodiacetamide were added to a 37wt% hydrochloric acid aqueous solution at a molar ratio of 1:1 to 8 times the mass of p-hydroxybenzaldehyde. The mixture was stirred at room temperature for 22 h, and then ice water at a molar ratio of 40 times the mass of p-hydroxybenzaldehyde was added. The mixture was washed with deionized water until pH=5, filtered, and dried under vacuum at 50℃ for 24 h to obtain intermediate A. Intermediate A and 4-dimethylaminobutyric acid were added to a dichloroisocyanuric acid aqueous solution at a molar ratio of 1:1 to 8 times the mass of intermediate A. Palladium acetate (0.01 times the mass of intermediate A) and potassium phosphate (0.03 times the mass of intermediate A) were added to methane. The mixture was stirred and refluxed at 75°C for 70 min, filtered, and the filtrate was evaporated under reduced pressure to obtain intermediate B. Sodium hypochlorite, deionized water, and tert-butanol were mixed evenly in a mass ratio of 1:2:8 to prepare a chlorination-modified solution. Intermediate B and the chlorination-modified solution were mixed evenly in a mass ratio of 1:10, stirred at room temperature for 4 h, and evaporated under reduced pressure to obtain a composite antibacterial agent. (2) The protective powder, deionized water and anhydrous ethanol were mixed in a mass ratio of 1:10:60 and ultrasonically dispersed for 1 h. γ-chloropropyltriethoxysilane with a mass of 0.2 times that of the protective powder was added and stirred at 60 °C for 6 h. The mixture was filtered, washed three times with anhydrous ethanol, and vacuum dried at 60 °C for 12 h to obtain the pre-modified protective powder. The pre-modified protective powder and anhydrous ethanol were mixed in a mass ratio of 1:20 and ultrasonically dispersed for 20 min. A composite antibacterial agent with a mass of 3 times that of the pre-modified protective powder was added, and potassium iodide with a mass of 0.04 times that of the composite antibacterial agent was added. The mixture was stirred at 70 °C for 40 h under nitrogen protection, filtered, washed three times with anhydrous ethanol, and vacuum dried at 60 °C for 22 h to obtain the modified protective powder. (3) Add phenylphosphoryl dichloride, diethyl iminodiacetic acid and triethylamine in a molar ratio of 1:2:2 to chloroform with a mass of 8 times that of phenylphosphoryl dichloride, add 4-dimethylaminopyridine with a mass of 0.008 times that of phenylphosphoryl dichloride, stir and reflux at 65°C for 24 h, and distill under reduced pressure to obtain product 1; mix product 1 and tetrahydrofuran in a mass ratio of 1:6, add ethylenediamine with a molar amount of 6 times that of product 1 dropwise at a uniform rate within 30 min, heat to 60°C and stir for 5 h, and distill under reduced pressure to obtain product 2; add product 2 and benzothiazole-2-carboxaldehyde in a molar ratio of 1:4 to N,N-dimethylformamide with a mass of 8 times that of product 2, stir and react at 50°C for 8 h, and dry under vacuum at 80°C for 20 h to obtain phosphorus-nitrogen-sulfur flame retardant; (4) Take 40 parts of modified protective powder, 8 parts of phosphorus-nitrogen-sulfur flame retardant, and 50 parts of thermoplastic polyurethane by mass. Mix the modified protective powder, phosphorus-nitrogen-sulfur flame retardant, and thermoplastic polyurethane. Adjust the viscosity to 7 Pa·S with N,N-dimethylformamide and defoam under vacuum to obtain a protective slurry. Apply the protective slurry to the fabric surface with a 100 μm coating line rod. Dry at 70°C for 20 min and vacuum dry at 40°C for 80 min to obtain a flexible material with radiation protection function.

[0036] A method for preparing radiation-shielding yarn, the preparation process is as follows: The radiation-resistant flexible material prepared in step (4) of Example 1 was slit using a precision slitting device. The slitting width was controlled to be 1 mm, the slitting speed was adjusted to 6 m / min, and the gap between the slitting blades was controlled to be 0.02 mm. After slitting, the obtained protective narrow strip was fed into a twisting device. The twisting speed was set to 900 r / min, the twisting degree was 30 twists / 10 cm, and the tension was controlled to be 10 N during the twisting process to obtain the radiation-resistant yarn.

[0037] Example 2: A method for preparing a radiation-shielding flexible material includes the following preparation steps: (1) p-hydroxybenzaldehyde and iminodiacetamide were added to a 37wt% hydrochloric acid aqueous solution at a molar ratio of 1:1.05 to 9 times the mass of p-hydroxybenzaldehyde. The mixture was stirred at room temperature for 24 hours, and then 45 times the mass of p-hydroxybenzaldehyde was added to ice water. The mixture was washed with deionized water until pH=5, filtered, and dried under vacuum at 55℃ for 22 hours to obtain intermediate A. Intermediate A and 4-dimethylaminobutyric acid were added to a 37wt% hydrochloric acid aqueous solution at a molar ratio of 1:1 to 9 times the mass of intermediate A. Palladium acetate (0.015 times the mass of intermediate A) and potassium phosphate (0.035 times the mass of intermediate A) were added to alkane. The mixture was stirred and refluxed at 80°C for 65 min, filtered, and the filtrate was evaporated under reduced pressure to obtain intermediate B. Sodium hypochlorite, deionized water, and tert-butanol were mixed evenly in a mass ratio of 1:2.5:9 to prepare a chlorination-modified solution. Intermediate B and the chlorination-modified solution were mixed evenly in a mass ratio of 1:11, stirred at room temperature for 5 h, and evaporated under reduced pressure to obtain a composite antibacterial agent. (2) The protective powder, deionized water and anhydrous ethanol were mixed in a mass ratio of 1:13:70 and ultrasonically dispersed for 1.5 h. γ-chloropropyltriethoxysilane with a mass of 0.25 times that of the protective powder was added and stirred at 65 °C for 5.5 h. The mixture was filtered, washed 4 times with anhydrous ethanol, and vacuum dried at 65 °C for 11 h to obtain the pre-modified protective powder. The pre-modified protective powder and anhydrous ethanol were mixed in a mass ratio of 1:25 and ultrasonically dispersed for 25 min. A composite antibacterial agent with a mass of 4 times that of the pre-modified protective powder was added and potassium iodide with a mass of 0.05 times that of the composite antibacterial agent was added. The mixture was stirred at 74 °C for 35 h under nitrogen protection, filtered, washed 4 times with anhydrous ethanol, and vacuum dried at 65 °C for 21 h to obtain the modified protective powder. (3) Add phenylphosphoryl dichloride, diethyl iminodiacetic acid, and triethylamine in a molar ratio of 1:2:2 to chloroform with a mass of 9 times that of phenylphosphoryl dichloride, add 4-dimethylaminopyridine with a mass of 0.009 times that of phenylphosphoryl dichloride, stir and reflux at 70°C for 22 h, and distill under reduced pressure to obtain product 1; mix product 1 and tetrahydrofuran in a mass ratio of 1:7, add ethylenediamine with a molar amount of 7 times that of product 1 dropwise at a uniform rate over 30 min, heat to 63°C and stir for 4.5 h, and distill under reduced pressure to obtain product 2; add product 2 and benzothiazole-2-carboxaldehyde in a molar ratio of 1:4 to N,N-dimethylformamide with a mass of 9 times that of product 2, stir and react at 55°C for 7.5 h, and dry under vacuum at 85°C for 18 h to obtain phosphorus-nitrogen-sulfur flame retardant; (4) Take 45 parts of modified protective powder, 9 parts of phosphorus-nitrogen-sulfur flame retardant, and 55 parts of thermoplastic polyurethane by mass. Mix the modified protective powder, phosphorus-nitrogen-sulfur flame retardant, and thermoplastic polyurethane. Adjust the viscosity to 7.5 Pa·S with N,N-dimethylformamide. Defoam under vacuum to obtain a protective slurry. Apply the protective slurry to the fabric surface with a 100 μm coating line. Dry at 75°C for 15 min and vacuum dry at 45°C for 70 min to obtain a flexible material with radiation protection function.

[0038] Example 3: A method for preparing a radiation-shielding flexible material includes the following preparation steps: (1) p-hydroxybenzaldehyde and iminodiacetic acid diamide were added to a 37wt% hydrochloric acid aqueous solution at a molar ratio of 1:1.1 to 10 times the mass of p-hydroxybenzaldehyde. The mixture was stirred at room temperature for 26 hours, and then ice water at a molar ratio of 50 times the mass of p-hydroxybenzaldehyde was added. The mixture was washed with deionized water until pH=5, filtered, and vacuum dried at 60℃ for 20 hours to obtain intermediate A. Intermediate A and 4-dimethylaminobutyric acid were added to a 37wt% hydrochloric acid aqueous solution at a molar ratio of 1:1 to 10 times the mass of intermediate A. Palladium acetate (0.02 times the mass of intermediate A) and potassium phosphate (0.04 times the mass of intermediate A) were added to chloromethane. The mixture was stirred and refluxed at 85°C for 60 min, filtered, and the filtrate was evaporated under reduced pressure to obtain intermediate B. Sodium hypochlorite, deionized water, and tert-butanol were mixed evenly in a mass ratio of 1:3:10 to prepare a chlorination-modified solution. Intermediate B and the chlorination-modified solution were mixed evenly in a mass ratio of 1:12, stirred at room temperature for 6 h, and evaporated under reduced pressure to obtain a composite antibacterial agent. (2) The protective powder, deionized water and anhydrous ethanol were mixed in a mass ratio of 1:16:80 and ultrasonically dispersed for 2 hours. γ-chloropropyltriethoxysilane with a mass of 0.3 times that of the protective powder was added and stirred at 70°C for 5 hours. The mixture was filtered, washed 5 times with anhydrous ethanol, and vacuum dried at 60°C for 12 hours to obtain the pre-modified protective powder. The pre-modified protective powder and anhydrous ethanol were mixed in a mass ratio of 1:30 and ultrasonically dispersed for 30 minutes. A composite antibacterial agent with a mass of 5 times that of the pre-modified protective powder was added, along with potassium iodide with a mass of 0.06 times that of the composite antibacterial agent. The mixture was stirred at 78°C for 30 hours under nitrogen protection, filtered, washed 5 times with anhydrous ethanol, and vacuum dried at 70°C for 20 hours to obtain the modified protective powder. (3) Add phenylphosphonate dichloride, diethyl iminodiacetic acid and triethylamine in a molar ratio of 1:2:2 to chloroform with a mass of 10 times that of phenylphosphonate dichloride, add 4-dimethylaminopyridine with a mass of 0.01 times that of phenylphosphonate dichloride, stir and reflux at 75°C for 20 h, and distill under reduced pressure to obtain product 1; mix product 1 and tetrahydrofuran in a mass ratio of 1:8, add ethylenediamine with a molar amount of 8 times that of product 1 dropwise at a uniform rate within 30 min, heat to 66°C and stir to react for 4 h, and distill under reduced pressure to obtain product 2; add product 2 and benzothiazole-2-carboxaldehyde in a molar ratio of 1:4 to N,N-dimethylformamide with a mass of 10 times that of product 2, stir to react at 60°C for 7 h, and dry under vacuum at 90°C for 16 h to obtain phosphorus-nitrogen-sulfur flame retardant; (4) Take 50 parts of modified protective powder, 10 parts of phosphorus-nitrogen-sulfur flame retardant, and 60 parts of thermoplastic polyurethane by mass. Mix the modified protective powder, phosphorus-nitrogen-sulfur flame retardant, and thermoplastic polyurethane. Adjust the viscosity to 8 Pa·S with N,N-dimethylformamide. Defoam under vacuum to obtain a protective slurry. Apply the protective slurry to the fabric surface with a 100 μm coating line. Dry at 80°C for 10 min and vacuum dry at 50°C for 60 min to obtain a flexible material with radiation protection function.

[0039] Comparative Example 1: The difference between Comparative Example 1 and Example 2 is that Comparative Example 1 omits step (1) when preparing the radiation-shielding flexible material, and modifies step (2) as follows: The protective powder, deionized water, and anhydrous ethanol are mixed in a mass ratio of 1:13:70, ultrasonically dispersed for 1.5 h, and then 0.25 times the mass of the protective powder is added to γ-chloropropyltriethoxysilane. The mixture is stirred at 65°C for 5.5 h, filtered, washed four times with anhydrous ethanol, and vacuum dried at 65°C for 11 h to obtain the modified protective powder. In other words, only the silane coupling agent is used to modify the protective powder. The remaining processes are consistent with Example 2.

[0040] Comparative Example 2: The difference between Comparative Example 2 and Example 2 is that Comparative Example 2 omits step (3) in preparing the radiation-shielding flexible material, and modifies step (4) as follows: 45 parts of modified protective powder and 55 parts of thermoplastic polyurethane are taken by mass; the modified protective powder and thermoplastic polyurethane are mixed, and the viscosity is adjusted to 7.5 Pa·s with N,N-dimethylformamide, and vacuum defoamed to obtain a protective slurry; the protective slurry is coated onto the fabric surface with a 100 μm coating line, dried at 75°C for 15 min, and vacuum dried at 45°C for 70 min to obtain the radiation-shielding flexible material. That is, "phosphorus-nitrogen-sulfur flame retardant" is not added in step (4). The remaining processes are consistent with Example 2.

[0041] Experimental example: 1. Radiation protection effect test: The standard document referenced for the test is GBZ / T 147-2002 Determination of attenuation performance of X-ray protective materials. The test was conducted using an ATOMTEX AT1123 dose rate meter to measure the ambient dose equivalent rate H*(10) and calculate the radiation protection ratio. 100mCl 241Am was used as the radiation source during the measurement. A narrow beam confinement was used for the measurement, with the detector 30cm away from the sample and the sample 70cm away from the radiation source.

[0042] The formula for calculating the radiation protection ratio is as follows:

[0043] Where: N d N represents the dose rate after sample addition. o N represents the dose rate without the sample; b This represents the background dose rate.

[0044] 2. Flame retardant effect test: Refer to the test method of GB / T 5454-1997 "Test for Burning Performance of Textiles - Oxygen Index Method" to test the LOI values ​​of the example and comparative examples.

[0045] 3. Antibacterial effect test: Referring to the national standard GB / T 20944.3-2008 "Evaluation of antibacterial properties of textiles - Part 3: Shaking method", the selected bacterial species was Escherichia coli, and the antibacterial rate of the test examples and comparative examples was tested.

[0046] The results of the above experiments are shown in the table below.

[0047]

[0048] Analysis of the experimental data in the table shows that the radiation protection ratios of the examples and comparative examples are all above 80%, indicating that the radiation-protective flexible material prepared in this application has superior radiation protection function.

[0049] The limiting oxygen index of Examples 1-3 is higher than that of Comparative Example 2, which indicates that the present application prepared a phosphorus-nitrogen-sulfur flame retardant and applied it to the fabric. This multi-element composite flame retardant has a better flame retardant ability than a single-component flame retardant, giving the radiation-proof flexible material superior flame retardant ability.

[0050] The antibacterial rates of Examples 1-3 are greater than those of Comparative Example 1, indicating that the present invention has prepared a composite antibacterial agent. The composite antibacterial agent undergoes a quaternization reaction with the protective powder modified by the silane coupling agent, grafting halogen amine antibacterial components and quaternary ammonium salt structures onto the protective powder, thereby exerting a dual-active antibacterial effect and endowing the material with excellent antibacterial ability.

[0051] The antibacterial rates of Examples 1-3 are greater than those of Comparative Example 2, indicating that the benzothiazole structure on the phosphorus-nitrogen-sulfur flame retardant also has a certain antibacterial ability.

[0052] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A flexible material with radiation protection function, characterized in that, The aforementioned radiation-resistant flexible material is prepared by mixing modified protective powder, phosphorus-nitrogen-sulfur flame retardant, and thermoplastic polyurethane, using N,N-dimethylformamide as a dispersant, to form a protective slurry; the protective slurry is then coated onto the surface of a fabric and dried. The modified protective powder is prepared by reacting pre-modified protective powder and composite antibacterial agent; The pre-modified protective powder is prepared by reacting protective powder with γ-chloropropyltriethoxysilane.

2. The radiation-shielding flexible material as described in claim 1, characterized in that, The composite antibacterial agent is obtained by chlorinating intermediate B with sodium hypochlorite. Intermediate B is prepared by reacting intermediate A with 4-dimethylaminobutyric acid. Intermediate A is prepared by reacting p-hydroxybenzaldehyde and iminodiacetamide.

3. The radiation-shielding flexible material as described in claim 1, characterized in that, The phosphorus-nitrogen-sulfur flame retardant is prepared by reacting product 2 with benzothiazole-2-carboxaldehyde. Product 2 is prepared by reacting product 1 with ethylenediamine. Product 1 is prepared by reacting phenylphosphodichloro and diethyl iminodiacetate.

4. The radiation-shielding flexible material as described in claim 1, characterized in that, The protective powder includes, but is not limited to, one or more of the following: gadolinium oxide powder, bismuth powder, tungsten oxide powder, rare earth element oxide powder (lanthanum, yttrium, cerium oxide, etc.), boride powder, and metal-organic framework-derived high atomic number metal oxide powder.

5. A method for preparing a radiation-shielding flexible material, characterized in that, The preparation method of the radiation-shielding flexible material includes the following steps: (1) Sodium hypochlorite, deionized water and tert-butanol are mixed evenly in a mass ratio of 1:(2~3):(8~10) to prepare a chlorination-modified solution; intermediate B and chlorination-modified solution are mixed evenly in a mass ratio of 1:(10~12), stirred at room temperature for 4~6 hours, and evaporated under reduced pressure to obtain a composite antibacterial agent. (2) Mix the pre-modified protective powder and anhydrous ethanol at a mass ratio of 1:(20~30), sonicate for 20~30 min, add 3~5 times the mass of the pre-modified protective powder and 0.04~0.06 times the mass of the composite antibacterial agent, add potassium iodide, stir and react at 70~78℃ for 30~40 h under nitrogen protection, filter, wash with anhydrous ethanol 3~5 times, and vacuum dry at 60~70℃ for 20~22 h to obtain the modified protective powder; (3) Add product 2 and benzothiazole-2-carboxaldehyde to N,N-dimethylformamide at a molar ratio of 1:4, which is 8 to 10 times the mass of product 2. Stir and react at 50 to 60°C for 7 to 8 hours, and then vacuum dry at 80 to 90°C for 16 to 20 hours to obtain phosphorus-nitrogen-sulfur flame retardant. (4) Mix the modified protective powder, phosphorus-nitrogen-sulfur flame retardant and thermoplastic polyurethane, adjust the viscosity to 7~8 Pa·S with N,N-dimethylformamide, and defoam under vacuum to obtain a protective slurry; use a 100μm coating line to coat the protective slurry onto the fabric surface, dry at 70~80℃ for 10~20min, and vacuum dry at 40~50℃ for 60~80min to obtain a flexible material with radiation protection function.

6. The method for preparing a radiation-shielding flexible material as described in claim 5, characterized in that, The preparation method of intermediate B in step (1) is as follows: intermediate A and 4-dimethylaminobutyric acid are added to dichloromethane at a molar ratio of 1:1, which is 8 to 10 times the mass of intermediate A. Palladium acetate is added at 0.01 to 0.02 times the mass of intermediate A, and potassium phosphate is added at 0.03 to 0.04 times the mass of intermediate A. The mixture is stirred and refluxed at 75 to 85°C for 60 to 70 minutes. After filtration, the filtrate is evaporated under reduced pressure to obtain intermediate B.

7. The method for preparing a radiation-shielding flexible material as described in claim 6, characterized in that, The intermediate A is prepared as follows: p-hydroxybenzaldehyde and iminodiacetamide are added to a 37wt% hydrochloric acid aqueous solution at a molar ratio of 1:(1~1.1) to 8~10 times the mass of p-hydroxybenzaldehyde. The mixture is stirred at room temperature for 22~26h, then ice water is added to 40~50 times the mass of p-hydroxybenzaldehyde. The mixture is washed with deionized water until pH=5, filtered, and vacuum dried at 50~60℃ for 20~24h to obtain intermediate A.

8. The method for preparing a radiation-shielding flexible material as described in claim 5, characterized in that, The preparation method of the pre-modified protective powder in step (2) is as follows: the protective powder, deionized water and anhydrous ethanol are mixed in a mass ratio of 1:(10~16):(60~80), ultrasonically dispersed for 1~2h, γ-chloropropyltriethoxysilane with a mass of 0.2~0.3 times that of the protective powder is added, the mixture is stirred at 60~70℃ for 5~6h, filtered, washed with anhydrous ethanol 3~5 times, and vacuum dried at 60~70℃ for 10~12h to obtain the pre-modified protective powder.

9. The method for preparing a radiation-shielding flexible material as described in claim 5, characterized in that, The preparation method of product 2 in (3) is as follows: product 1 and tetrahydrofuran are mixed in a mass ratio of 1:6~8, and ethylenediamine of 6~8 times the molar amount of product 1 is added dropwise at a uniform rate within 30 min. The temperature is raised to 60~66℃ and stirred for 4~5 h. The product 2 is obtained by vacuum distillation. The preparation method of product 1 is as follows: phenylphosphine dichloride, diethyl iminodiacetic acid, and triethylamine are added to chloroform at a molar ratio of 1:2:2, which is 8 to 10 times the mass of phenylphosphine dichloride. Then, 4-dimethylaminopyridine is added at a mass of 0.008 to 0.01 times the mass of phenylphosphine dichloride. The mixture is stirred and refluxed at 65 to 75°C for 20 to 24 hours, and then distilled under reduced pressure to obtain product 1.

10. The method for preparing a radiation-shielding flexible material as described in claim 5, characterized in that, The dosage relationship of the modified protective powder, phosphorus-nitrogen-sulfur flame retardant and thermoplastic polyurethane in step (4) is as follows: by mass parts, 40-50 parts of modified protective powder, 8-10 parts of phosphorus-nitrogen-sulfur flame retardant and 50-60 parts of thermoplastic polyurethane.

Images