Thermoplastic elastomer-based flexible composite shielding material and preparation method thereof

Abstract

The invention discloses a thermoplastic elastomer-based flexible composite shielding material which comprises a thermoplastic elastomer, a neutron shielding component, a gamma-ray shielding component, an antioxidant and a release agent, the neutron shielding component adopts neutron shielding materials such as boron carbide, boron powder, boron nitride, boron oxide and gadolinium oxide modified by a silane coupling agent; the gamma-ray shielding component adopts gamma-ray shielding materials such as tungsten powder, tungsten oxide, bismuth powder, bismuth oxide and the like modified by titanate coupling agents, so that double shielding of neutrons and secondary gamma rays can be realized. The compatibility of the inorganic filler and the thermoplastic elastomer matrix is improved through surface modification treatment, the mechanical property of the composite shielding material is improved, the composite shielding material is suitable for a high-load scene by adjusting the hardness of the elastomer, and the flexibility and comfort of personnel protection equipment can also be improved. The preparation method disclosed by the invention is high in process maturity, simple and convenient to operate and easy to adjust according to application scene requirements, and has large-scale production and commercial application prospects.

Description

Technical Field

[0001] This invention belongs to the field of radiation shielding material preparation technology, and particularly relates to a thermoplastic elastomer-based flexible composite shielding material and its preparation method. Background Technology

[0002] With the rapid development of nuclear technology, the demand for radiation protection materials is becoming increasingly urgent. Neutrons and gamma rays have high penetrating power and can cause harm to personnel and the environment, while also potentially interfering with the normal operation of precision instruments. Flexible shielding materials, with their excellent conformability, play a crucial role in the protection of irregularly shaped components and personnel. Therefore, the development of composite shielding materials that combine flexibility and lightweight properties to achieve dual radiation protection is of significant practical importance.

[0003] Existing flexible neutron and gamma-ray shielding materials mostly use vulcanized rubber as the base material, with functional shielding components added to achieve the protective effect. While vulcanized rubber has good mechanical properties, it requires a vulcanization process, which is time-consuming, has low production efficiency, and requires mold replacement for changing the shape of the product, resulting in extremely high costs. Patent CN119875163A discloses a flexible neutron shielding material that uses EPDM rubber as the base material and functionalized boron carbide and high-density polyethylene fiber as thermal and fast neutron shielding fillers, obtained through mixing and vulcanization. Patent CN117373714A discloses a silicone rubber composite material that achieves dual protection through alternating stacked neutron and gamma-ray shielding layers.

[0004] Thermoplastic elastomers (TPEs) possess excellent processing properties, requiring no vulcanization process and can be processed through injection molding, extrusion, and other methods, significantly improving production efficiency and achieving high dimensional accuracy. Furthermore, TPEs exhibit good elasticity and mechanical properties, are recyclable, and meet environmental protection requirements. Therefore, using thermoplastic rubber as a matrix material to prepare composite shielding materials shows broad application prospects in the field of radiation protection. Currently, a few patents have been developed using TPEs as a substrate to prepare shielding materials. For example, patent CN117165022A uses TPEs and gadolinium oxide to prepare flexible shielding materials for gamma and neutron rays. Patent CN104021832A uses TPEs, boron compounds, lead-tungsten, and their compounds to prepare a radiation shielding suit for medical use. Existing patents using TPEs as a substrate can achieve dual protection against neutrons and gamma rays by adding functional components. However, the large difference in interfacial energy between TPEs and fillers means that conventional mixing processes can easily lead to the aggregation of functional shielding components, affecting shielding performance and mechanical properties. Therefore, developing a flexible composite shielding material that provides both neutron and gamma-ray protection, is simple to manufacture, and has good dispersion of functional shielding components is an urgent problem to be solved. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a thermoplastic elastomer-based flexible composite shielding material and its preparation method. The preparation process of this composite shielding material is simple and easy to implement. By adding various types of functional fillers, it can fully accommodate multiple shielding and protective properties, providing ample room for the diversification of material properties. This composite shielding material itself is rich in hydrogen, thus possessing excellent fast neutron protection performance and effectively resisting the radiation hazards of fast neutrons. Furthermore, this composite shielding material exhibits excellent flexibility, making it an ideal choice for preparing personal protective equipment, capable of meeting the requirements for flexibility and comfort in various scenarios.

[0006] In a first aspect, the present invention discloses a thermoplastic elastomer-based flexible composite shielding material, comprising the following components by weight: 100 parts of thermoplastic elastomer, 5-100 parts of neutron shielding component, 5-100 parts of gamma-ray shielding component, 0.5-4.0 parts of antioxidant, and 0.2-2.0 parts of release agent.

[0007] Furthermore, the thermoplastic elastomer is at least one of styrene-based thermoplastic elastomers SBS, SIS, and SEBS, and the hardness of the thermoplastic elastomer is 0~30A.

[0008] Furthermore, the neutron shielding component is a neutron shielding material powder modified with a silane coupling agent. The neutron shielding material includes at least one of boron carbide, boron powder, boron nitride, boron oxide, and gadolinium oxide, and the average particle size of the neutron shielding material powder is ≤40μm.

[0009] Furthermore, the silane coupling agent modification process includes: preparing an ethanol aqueous solution with a silane coupling agent concentration of 1-3 wt%, adjusting the pH value of the solution to 3-6, adding neutron shielding material powder to the ethanol aqueous solution, and then drying it after ultrasonic treatment and mechanical stirring to obtain neutron shielding material powder modified by silane coupling agent; the silane coupling agent includes KH550 and KH570.

[0010] Furthermore, the gamma-ray shielding component is a gamma-ray shielding material powder modified with a titanate coupling agent. The gamma-ray shielding material includes at least one of tungsten powder, tungsten oxide, bismuth powder, and bismuth oxide, and the average particle size of the gamma-ray shielding material powder is ≤20μm.

[0011] Furthermore, the titanate coupling agent modification process includes: preparing an ethyl acetate solution with a titanate coupling agent concentration of 1-3 wt%; adding the dried γ-ray shielding material powder to the ethyl acetate solution to obtain a slurry; ball milling the slurry at room temperature; and vacuum drying the slurry after ball milling to completely remove the solvent, thereby obtaining γ-ray shielding material powder modified with titanate coupling agents; wherein the titanate coupling agents include NDZ-101, NDZ-201, and NDZ-311.

[0012] Furthermore, the antioxidants include antioxidant 1010, antioxidant 168, antioxidant 1076, and antioxidant 626.

[0013] Furthermore, the release agent includes calcium stearate, silicone powder, and high-temperature wax.

[0014] Secondly, the present invention also discloses a method for preparing a thermoplastic elastomer-based flexible composite shielding material. The thermoplastic elastomer-based flexible composite shielding material is the thermoplastic elastomer-based flexible composite shielding material of the first aspect of the present invention. The preparation method includes: mixing and stirring a thermoplastic elastomer, a neutron shielding component, a gamma-ray shielding component, an antioxidant, and a release agent according to the mass ratio of each component in the composite shielding material, and then melting, extruding, and casting the mixed raw material through a soft rubber extruder to obtain the thermoplastic elastomer-based flexible composite shielding material.

[0015] Furthermore, the melt extrusion and casting molding process includes: adding the uniformly mixed raw materials into a soft rubber extruder for melt extrusion, wherein the soft rubber extruder is temperature-controlled in stages: the temperature of the first zone is 130~150℃, the temperature of the second zone is 160~180℃, the temperature of the third zone is 180~200℃, and the temperature of the fourth zone is 180~200℃; after the material flows out of the extruder, it is transferred to the mold to cool and form, thereby obtaining a thermoplastic elastomer-based flexible composite shielding material.

[0016] This invention provides a thermoplastic elastomer-based flexible composite shielding material and its preparation method. Compared with the prior art, this invention has at least the following advantages: 1. The thermoplastic elastomer selected in this invention possesses excellent processing properties. Composite shielding materials of the desired shape can be prepared through processes such as melt blending and extrusion, without the need for vulcanization. The production process is simple and easy to implement, and the formulation components can be adjusted according to different application scenarios with varying dosage ranges to achieve higher shielding efficiency. Furthermore, the composite shielding material of this invention has high production efficiency, is recyclable, meets environmental protection requirements, and the finished product exhibits excellent flexibility and lightweight properties, making it suitable for a wider range of applications, including neutron and gamma-ray shielding in nuclear industry, medical, aerospace, and scientific research.

[0017] 2. The composite shielding material of this invention simultaneously incorporates fast neutron moderators, thermal neutron absorbers, and gamma-ray shielding materials, enabling effective slowing and absorption of fast neutrons. The gamma-ray shielding material effectively shields secondary gamma rays generated by the interaction of neutrons with matter, thus achieving dual shielding against neutrons and secondary gamma rays, significantly improving the overall radiation protection effect of the material.

[0018] 3. This invention modifies the inorganic filler by using silane coupling agents to surface-modify the neutron shielding component and titanate coupling agents to surface-modify the gamma-ray shielding component. This effectively improves the compatibility between the inorganic filler and the thermoplastic elastomer matrix, reduces stress concentration at the interface, and thus gives the composite shielding material good mechanical properties. It can withstand certain external forces and is not prone to cracking or breakage, expanding its application range to applications requiring certain loads. Moreover, the modification method of this invention has high process maturity, is simple to operate, and is easy to integrate with the composite shielding material preparation method of this invention, showing promise for large-scale production and commercial application. Detailed Implementation

[0019] The technical solutions of this application will be clearly and completely described below with reference to the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0020] Unless otherwise specified, all temperatures mentioned herein are in degrees Celsius, and the preferred embodiments can be freely combined as needed. Those skilled in the art will understand that the data and parameters described in the examples are merely exemplary and do not constitute a limitation of the invention. All components used in the following examples and comparative examples are compounds known in the art, and all equipment used is equipment publicly known in the art. All components and equipment used in this invention can be obtained commercially or prepared using known techniques.

[0021] This invention provides a thermoplastic elastomer-based flexible composite shielding material, comprising the following components by weight: 100 parts thermoplastic elastomer, 5-100 parts neutron shielding component, 5-100 parts gamma-ray shielding component, 0.5-4.0 parts antioxidant, and 0.2-2.0 parts release agent.

[0022] The thermoplastic elastomer of the present invention is preferably a styrene-based thermoplastic elastomer, more preferably at least one of SBS, SIS, and SEBS, and the hardness of the thermoplastic elastomer is preferably 0~30A.

[0023] The neutron shielding component of the present invention preferably uses neutron shielding material powder modified with a silane coupling agent. The neutron shielding material preferably includes at least one of boron carbide, boron powder, boron nitride, boron oxide, and gadolinium oxide. The average particle size of the neutron shielding material powder is preferably ≤40μm.

[0024] Preferably, the silane coupling agent modification process of the present invention includes: preparing an ethanol-water solution with a silane coupling agent concentration of 1-3 wt%, adjusting the pH of the solution to 3-6 using acetic acid, adding neutron shielding material powder to the ethanol-water solution, subjecting it to ultrasonic treatment at 50-70°C for 30 min and mechanical stirring at 70-90°C for 60 min, and then drying it at 100-120°C for 2 h to obtain neutron shielding material powder modified with silane coupling agent. The ultrasonic treatment time and temperature, as well as the mechanical stirring time and temperature, can be adjusted according to the actual amount of neutron shielding material powder used. When the amount of neutron shielding material powder is large, the ultrasonic treatment and mechanical stirring time and temperature can be appropriately increased. The time and temperature used should be sufficient to achieve adequate mixing and contact between the neutron shielding material powder and the silane coupling agent. The preferred silane coupling agents used in this invention are KH550 and KH570.

[0025] The gamma-ray shielding component of the present invention preferably uses gamma-ray shielding material powder modified with a titanate coupling agent. The gamma-ray shielding material preferably includes at least one of tungsten powder, tungsten oxide, bismuth powder, and bismuth oxide. The average particle size of the gamma-ray shielding material powder is preferably ≤20μm.

[0026] Preferably, the titanate coupling agent modification process of the present invention includes: preparing an ethyl acetate solution with a titanate coupling agent concentration of 1-3 wt%, more preferably 2 wt%; adding the dried γ-ray shielding material powder to the ethyl acetate solution to obtain a slurry; ball milling the slurry at room temperature; the ball milling process is as follows: using zirconia ball milling balls, a ball-to-material ratio of 5:1, a rotation speed of 300 r / min, and a ball milling time of 2 h; during the ball milling process, the slurry temperature should always be kept at room temperature to avoid decomposition of the titanate coupling agent due to overheating; after ball milling, drying the slurry in a vacuum oven at 80°C for 4 h to completely remove the solvent, thereby obtaining γ-ray shielding material powder modified with titanate coupling agent. The above-mentioned ball milling and drying process parameters can be adjusted according to the actual amount of γ-ray shielding material powder used. When the amount of γ-ray shielding material powder used is large, the ball-to-powder ratio, ball milling speed, ball milling time, drying temperature, and drying time can be appropriately increased. Of course, to improve ball milling efficiency and drying efficiency, the ball-to-powder ratio, ball milling speed, and drying temperature can also be appropriately increased. However, throughout the ball milling process, the slurry temperature should be kept at room temperature, and the drying temperature should be avoided from being too high, which could cause the titanate coupling agent to decompose due to overheating. The above process parameters should be set to ensure sufficient mixing and contact between the γ-ray shielding material powder and the titanate coupling agent, and to remove the solvent. The titanate coupling agents preferred in this invention include NDZ-101, NDZ-201, and NDZ-311.

[0027] The antioxidants preferred in this invention are antioxidant 1010, antioxidant 168, antioxidant 1076, and antioxidant 626, and the release agent is preferably calcium stearate, silicone powder, or high-temperature wax.

[0028] This invention also provides a method for preparing a thermoplastic elastomer-based flexible composite shielding material, wherein the thermoplastic elastomer-based flexible composite shielding material is the thermoplastic elastomer-based flexible composite shielding material provided by this invention, and the preparation method includes: S1. Pre-baking The thermoplastic elastomer was dried in a vacuum oven at 40-60℃ for 4-6 hours. S2. Mixing The pre-baked thermoplastic elastomer, neutron shielding component, gamma-ray shielding component, antioxidant, and release agent are added to a high-speed mixer according to the mass ratio of each component in the composite shielding material. The mixture is stirred at 800 r / min for 3-8 hours. Of course, the above speed and mixing time can be adjusted appropriately according to the actual amount of raw materials used. When the amount of raw materials used is large, or when it is necessary to improve the mixing efficiency, the speed and mixing time can be appropriately increased to ensure that the raw materials can be fully and evenly mixed. S3. Melt extrusion After the raw materials are mixed evenly, they are added to a soft rubber extruder for melt extrusion. The soft rubber extruder has segmented temperature control: Zone 1 temperature 130~150℃, Zone 2 temperature 160~180℃, Zone 3 temperature 180~200℃, and Zone 4 temperature 180~200℃. S4. Casting and molding After the material flows out of the soft rubber extruder, it is transferred to the mold to cool and form, thus obtaining a thermoplastic elastomer-based flexible composite shielding material.

[0029] The present invention will now be described in more detail with reference to exemplary embodiments. The following embodiments or experimental data are intended to illustrate the present invention by way of example, and those skilled in the art should understand that the present invention is not limited to these embodiments or experimental data.

[0030] Example 1 The preparation of a thermoplastic elastomer-based flexible composite shielding material includes the following steps: S1. Raw material preparation Weigh out 100 parts by weight of SEBS thermoplastic elastomer TPE with a hardness of 0, 5 parts of boron carbide powder modified by KH550, 5 parts of tungsten powder modified by NDZ-201, 0.3 parts of antioxidant 1076, 0.6 parts of antioxidant 168, and 0.5 parts of silicone powder; wherein the average particle size of boron carbide powder is 40 μm and the average particle size of tungsten powder is 20 μm. The preparation process of boron carbide powder modified by KH550 is as follows: prepare an ethanol aqueous solution with a KH550 concentration of 1wt%, adjust the pH value of the solution to about 3 using acetic acid, add boron carbide powder to the ethanol aqueous solution, and after ultrasonic treatment at 50℃ for 30 min and mechanical stirring at 90℃ for 60 min, dry at 120℃ for 2 h to obtain boron carbide powder modified by KH550. The preparation process of NDZ-201 modified tungsten powder is as follows: Prepare an ethyl acetate solution with NDZ-201 concentration of 1 wt%, add the dried tungsten powder to the ethyl acetate solution to obtain a slurry; ball mill the slurry at room temperature, add zirconium oxide milling balls to the milling jar at a ball-to-powder mass ratio of 5:1, mill at a speed of 300 r / min for 2 h; after milling, dry the slurry in a vacuum oven at 80℃ for 4 h to obtain NDZ-201 modified tungsten powder; S2. Mixing After drying TPE in a vacuum oven at 40℃ for 6 hours, it was added to a high-speed mixer along with other components and mixed and stirred at 800 r / min for 3 hours. S3. Melt extrusion The raw materials are added to a soft rubber extruder for melt extrusion. The soft rubber extruder has segmented temperature control: Zone 1 temperature 130℃, Zone 2 temperature 160℃, Zone 3 temperature 180℃, and Zone 4 temperature 180℃. S4. Casting and molding After the material flows out of the soft rubber extruder, it is transferred to the mold to cool and form, thus obtaining a thermoplastic elastomer-based flexible composite shielding material.

[0031] The performance of the thermoplastic elastomer-based flexible composite shielding material prepared in this embodiment was tested, and the test results are analyzed as follows: The composite shielding material of this embodiment has low density and soft material, and has a certain protective ability against neutron radiation and gamma-ray radiation, which can meet the basic protection requirements. The protective clothing made from it is lightweight, comfortable and easy to wear, and the production cost can be reduced by about 10-25%. It is suitable for scenarios with low doses of neutron radiation and gamma-ray radiation.

[0032] Example 2 The preparation of a thermoplastic elastomer-based flexible composite shielding material includes the following steps: S1. Raw material preparation Weigh out 100 parts by weight of SBS thermoplastic elastomer TPR with a hardness of 10, 100 parts of boron powder modified with KH570, 100 parts of tungsten oxide powder modified with NDZ-101, 2 parts of antioxidant 1010, 2 parts of antioxidant 626, and 2 parts of calcium stearate; wherein the average particle size of the boron powder is 40 μm and the average particle size of the tungsten oxide powder is 20 μm. The preparation process of boron powder modified by KH570 is as follows: prepare an ethanol aqueous solution with KH570 concentration of 3wt%, adjust the pH value of the solution to about 6 using acetic acid, add boron powder to the ethanol aqueous solution, and after ultrasonic treatment at 70℃ for 30 min and mechanical stirring at 70℃ for 60 min, dry at 100℃ for 2 h to obtain boron powder modified by KH570. The preparation process of NDZ-101 modified tungsten oxide powder is as follows: Prepare an ethyl acetate solution with a concentration of 3wt% NDZ-101, add the dried tungsten oxide powder to the ethyl acetate solution to obtain a slurry; ball mill the slurry at room temperature, add zirconium oxide milling balls to the milling jar at a ball-to-powder mass ratio of 5:1, mill at a speed of 300 r / min for 2 h; after milling, dry the slurry in a vacuum oven at 80℃ for 4 h to obtain NDZ-101 modified tungsten oxide powder; S2. Mixing After drying the TPR in a vacuum oven at 60°C for 4 hours, it was added to a high-speed mixer along with other components and mixed and stirred at 800 r / min for 8 hours. S3. Melt extrusion The raw materials are added to a soft rubber extruder for melt extrusion. The soft rubber extruder has segmented temperature control: the first zone temperature is 150℃, the second zone temperature is 180℃, the third zone temperature is 200℃, and the fourth zone temperature is 200℃. S4. Casting and molding After the material flows out of the soft rubber extruder, it is transferred to the mold to cool and form, thus obtaining a thermoplastic elastomer-based flexible composite shielding material.

[0033] The thermoplastic elastomer-based flexible composite shielding material prepared in this embodiment was subjected to performance testing. The test results are analyzed as follows: The composite shielding material of this embodiment has high density and certain hardness, and has extremely strong shielding ability against neutron radiation and gamma-ray radiation. Its tear resistance is about 10% higher than that of Example 1. It is suitable for applications such as nuclear industry and aerospace field where radiation shielding ability is extremely high and the mechanical properties of shielding materials are also required. For example, it can be used to make reactor shielding devices, waste transportation protection devices, spacecraft shielding covers, etc., and can effectively cope with high doses of neutron radiation and gamma-ray radiation.

[0034] Example 3 The preparation of a thermoplastic elastomer-based flexible composite shielding material includes the following steps: S1. Raw material preparation Weigh out 100 parts by weight of SIS thermoplastic elastomer TPR with a hardness of 30, 50 parts of gadolinium oxide powder modified by KH550, 50 parts of bismuth powder modified by NDZ-311, 2 parts of antioxidant 626, and 2 parts of high-temperature wax; wherein the average particle size of gadolinium oxide powder is 30 μm and the average particle size of bismuth powder is 15 μm. The preparation process of KH550 modified gadolinium oxide powder is as follows: prepare an ethanol aqueous solution with a KH550 concentration of 2wt%, adjust the pH value of the solution to about 5 using acetic acid, add gadolinium oxide powder to the ethanol aqueous solution, and after ultrasonic treatment at 60℃ for 30 min and mechanical stirring at 80℃ for 60 min, dry at 110℃ for 2 h to obtain KH550 modified gadolinium oxide powder; The preparation process of NDZ-311 modified bismuth powder is as follows: Prepare an ethyl acetate solution with a concentration of 2wt% for NDZ-311, add the dried bismuth powder to the ethyl acetate solution to obtain a slurry; ball mill the slurry at room temperature, add zirconium oxide milling balls to the milling jar at a ball-to-powder mass ratio of 5:1, mill at a speed of 300 r / min for 2 h; after milling, dry the slurry in a vacuum oven at 80℃ for 4 h to obtain NDZ-311 modified bismuth powder; S2. Mixing After drying TPR in a vacuum oven at 50°C for 5 hours, it was added to a high-speed mixer along with other components and mixed and stirred at 800 r / min for 5 hours. S3. Melt extrusion The raw materials are added to a soft rubber extruder for melt extrusion. The soft rubber extruder has segmented temperature control: Zone 1 temperature 140℃, Zone 2 temperature 170℃, Zone 3 temperature 190℃, and Zone 4 temperature 190℃. S4. Casting and molding After the material flows out of the soft rubber extruder, it is transferred to the mold to cool and form, thus obtaining a thermoplastic elastomer-based flexible composite shielding material.

[0035] The thermoplastic elastomer-based flexible composite shielding material prepared in this embodiment was subjected to performance testing. The test results are analyzed as follows: The composite shielding material of this embodiment has high density and high material hardness, and has strong protection against neutron and gamma-ray radiation. Its tear resistance is improved by about 25% compared with Example 1, and the raw material cost can be significantly reduced compared with Example 2. It is suitable for applications such as radiotherapy rooms and protective equipment in the field of nuclear medicine. It can meet the requirements of indoor fixed protective equipment for the mechanical properties and radiation shielding capabilities of shielding materials. The protective equipment made in this way is sturdy and durable, and can effectively shield neutron and gamma-ray radiation from hospital radiotherapy equipment.

[0036] Comparative Example 1 A thermoplastic elastomer-based flexible composite shielding material was prepared. In this comparative example, no gamma-ray shielding component was used. The remaining components and mass fractions of the composite shielding material, as well as the preparation method of the composite shielding material, were exactly the same as in Example 1.

[0037] The performance of the thermoplastic elastomer-based flexible composite shielding material prepared in this comparative example was tested, and the test results are analyzed as follows: Although the composite shielding material in this comparative example has low density, soft material and low production cost, it does not have gamma-ray radiation protection capability and has low neutron radiation protection capability, and is only suitable for low-dose scenarios where neutron radiation is the main radiation source.

[0038] Comparative Example 2 A thermoplastic elastomer-based flexible composite shielding material was prepared. Neutron shielding components were not used in this comparative example. The remaining components and mass fractions of the composite shielding material, as well as the preparation method of the composite shielding material, were exactly the same as in Example 1.

[0039] The performance of the thermoplastic elastomer-based flexible composite shielding material prepared in this comparative example was tested, and the test results are analyzed as follows: Although the composite shielding material in this comparative example has low density, soft material and low production cost, it does not have neutron radiation protection capability and has low gamma-ray radiation protection capability, and is only suitable for low-dose scenarios where gamma-ray radiation is the main radiation source.

[0040] Comparative Example 3 In preparing the thermoplastic elastomer-based flexible composite shielding material, neither the neutron shielding nor the gamma-ray shielding components in this comparative example underwent modification; only the original powder materials were used. Apart from this, the components, mass fractions, and preparation methods of the composite shielding material in this comparative example were completely identical to those in Example 1.

[0041] The performance of the thermoplastic elastomer-based flexible composite shielding material prepared in this comparative example was tested, and the results are analyzed as follows: The composite shielding material in this comparative example has weak neutron radiation and gamma-ray radiation protection capabilities, which is difficult to meet the basic protection requirements in practical applications.

[0042] All materials used in this invention are commercially available and can be purchased from retail sources. The above description is merely a preferred embodiment of the invention and is not intended to limit the invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A thermoplastic elastomer-based flexible composite shielding material, characterized in that, The product comprises the following components by weight: 100 parts thermoplastic elastomer, 5-100 parts neutron shielding component, 5-100 parts gamma-ray shielding component, 0.5-4.0 parts antioxidant, and 0.2-2.0 parts mold release agent.

2. The thermoplastic elastomer-based flexible composite shielding material according to claim 1, characterized in that, The thermoplastic elastomer is at least one of styrene-based thermoplastic elastomers SBS, SIS, and SEBS, and the hardness of the thermoplastic elastomer is 0~30A.

3. The thermoplastic elastomer-based flexible composite shielding material according to claim 1, characterized in that, The neutron shielding component is a neutron shielding material powder modified with a silane coupling agent. The neutron shielding material includes at least one of boron carbide, boron powder, boron nitride, boron oxide, and gadolinium oxide. The average particle size of the neutron shielding material powder is ≤40μm.

4. The thermoplastic elastomer-based flexible composite shielding material according to claim 3, characterized in that, The silane coupling agent modification process includes: preparing an ethanol aqueous solution with a silane coupling agent concentration of 1-3 wt%, adjusting the pH value of the solution to 3-6, adding neutron shielding material powder to the ethanol aqueous solution, and then drying it after ultrasonic treatment and mechanical stirring to obtain neutron shielding material powder modified by silane coupling agent; the silane coupling agent includes KH550 and KH570.

5. The thermoplastic elastomer-based flexible composite shielding material according to claim 1, characterized in that, The gamma-ray shielding component is a gamma-ray shielding material powder modified with a titanate coupling agent. The gamma-ray shielding material includes at least one of tungsten powder, tungsten oxide, bismuth powder, and bismuth oxide. The average particle size of the gamma-ray shielding material powder is ≤20μm.

6. The thermoplastic elastomer-based flexible composite shielding material according to claim 5, characterized in that, The titanate coupling agent modification process includes: preparing an ethyl acetate solution with a titanate coupling agent concentration of 1-3 wt%; adding the dried γ-ray shielding material powder to the ethyl acetate solution to obtain a slurry; ball milling the slurry at room temperature; and vacuum drying the slurry after ball milling to completely remove the solvent, thereby obtaining γ-ray shielding material powder modified with titanate coupling agents; the titanate coupling agents include NDZ-101, NDZ-201, and NDZ-311.

7. The thermoplastic elastomer-based flexible composite shielding material according to claim 1, characterized in that, The antioxidants include antioxidant 1010, antioxidant 168, antioxidant 1076, and antioxidant 626.

8. The thermoplastic elastomer-based flexible composite shielding material according to claim 1, characterized in that, The release agent includes calcium stearate, silicone powder, and high-temperature wax.

9. A method for preparing a thermoplastic elastomer-based flexible composite shielding material, characterized in that, The thermoplastic elastomer-based flexible composite shielding material is the thermoplastic elastomer-based flexible composite shielding material according to any one of claims 1-8. The preparation method includes: mixing and stirring the thermoplastic elastomer, neutron shielding component, gamma-ray shielding component, antioxidant, and release agent according to the mass ratio of each component in the composite shielding material, and then melting, extruding, and casting the mixed raw material through a soft rubber extruder to obtain the thermoplastic elastomer-based flexible composite shielding material.

10. The method for preparing the thermoplastic elastomer-based flexible composite shielding material according to claim 9, characterized in that, The melt extrusion and casting process includes: adding the uniformly mixed raw materials into a soft rubber extruder for melt extrusion; the soft rubber extruder has segmented temperature control: the first zone temperature is 130~150℃, the second zone temperature is 160~180℃, the third zone temperature is 180~200℃, and the fourth zone temperature is 180~200℃; after the material flows out of the extruder, it is transferred to the mold to cool and form, thereby obtaining a thermoplastic elastomer-based flexible composite shielding material.