CN110289115B - High-strength silicone rubber-based flexible neutron shielding material and preparation method thereof - Google Patents

Abstract

The invention discloses a high-strength silicone rubber-based flexible neutron shielding material and a preparation method thereof. In parts by weight, the formula comprises: 100 parts of silicone rubber base material, 128-174 parts of functionalized boride, and hydroxyl silicone oil compound 20 to 30 parts, 20 to 40 parts of long fiber carbon fiber. In the present invention, silicone rubber is used as the matrix, and the treated functionalized boride is uniformly dispersed therein, rolled into a sheet, laminated with the treated long-fiber carbon fiber, and then cross-linked by gamma radiation to obtain a High-strength silicone rubber-based flexible radiation shielding material with excellent performance; the flexible material not only has excellent neutron shielding effect, but also has excellent mechanical strength and heat resistance, and can be tailored in any shape according to the actual use scene.

Description

High-strength silicone rubber-based flexible neutron shielding material and preparation method thereof

technical field

The invention belongs to the technical field of special rubber materials and advanced composite materials thereof, and particularly relates to a high-strength silicone rubber-based flexible neutron shielding material and a preparation method thereof.

Background technique

Concrete, radiation-proof plexiglass (Singh VP, Bandiger N M, Chanthima N, Evaluation of gamma-ray exposure buildup factors and neutron shielding for bismuthborosilicate glasses, Radiation Physics and Chemistry, 2014, 98(1): 14-21), lead boron poly Ethylene (Zhang S J, Cao X B, Luan Y Q, Preparation and properties of smart thermalcontrol and radiation protection materials for multi-functional structure of small spacecraft, J Mater Sci Technol, 2011, 27(10):879-884), metal-based boron-containing materials Materials (Wu Gaohui, Jiang Longtao, Xu Zhonghua. A preparation method of a neutron absorption material. CN105200274A, 2015. Wang Wenxian, Chen Hongsheng, Huang Zheyuan. A preparation method of a copper-based neutron absorption material. CN 105950897A.2016.), etc., all It has good neutron shielding performance, but due to the lack of good flexibility, it is difficult to meet the special requirements of soft radiation protection materials for the protection of complex shapes in the periphery of nuclear facilities/equipment components, as well as interface gaps, track slits and other parts. need.

In recent years, flexible shielding materials have been reported (Chai H, Tang X B, Ni M X. Preparation and properties of flexible flame-retardant neutron shielding material based on methyl vinyl silicone rubber, Journal of Nuclear Materials, 2015, 464:210-215. Cheng Zhiyu , Qiu Yongfu, Chang Xueyi. A flexible low hydrogen neutron shielding material and its preparation method. CN108250557A, 2018. Chen Feida, Zhang Yun, Chen Tuo. A flexible graphene oxide hydrogel neutron radiation shielding material and its preparation method. Preparation method. CN107887046A, 2018.), but its mechanical strength is generally low (Kang Xingchuan, Guo Zhentao, Jiao Yang. A thermal neutron radiation shielding material and its preparation method. CN102708937A, 2012.), the maximum is only 3.43MPa, In addition, the catalyst used will be released during long-term use, causing potential safety risks and certain corrosion hazards to the surrounding environment or components. As a material for shielding neutrons, its service environment is often accompanied by high temperature and mechanical load in addition to radiation. This requires the material itself to have both good heat resistance and mechanical strength. At the same time, the material itself also needs to have a certain degree of cleanliness. to avoid potential safety risks or corrosion hazards to the surrounding environment or components due to the release of substances during use. In addition, improving the shielding efficiency of the material unit thickness is also an inevitable trend of development. Therefore, it is of great significance to research new flexible neutron shielding materials that not only have excellent neutron shielding effect, but also have excellent mechanical strength and heat resistance, and are also environmentally friendly.

SUMMARY OF THE INVENTION

SUMMARY OF THE INVENTION An object of the present invention is to address at least the above-mentioned problems and/or disadvantages and to provide at least the advantages that will be described hereinafter.

In order to achieve these objects and other advantages according to the present invention, a high-strength silicone rubber-based flexible neutron shielding material is provided. In parts by weight, the formula includes: 100 parts of silicone rubber base material, 128-174 parts of functionalized boride parts, 20-30 parts of hydroxyl silicone oil compound, and 20-40 parts of long fiber carbon fiber.

Preferably, the silicone rubber base material is a mixture of raw silicone rubber and silica with a mass ratio of 45-50:5-6, which needs to be fully kneaded before use.

Preferably, the raw silicone rubber is methyl vinyl silicone rubber or phenyl silicone rubber with a phenyl content of 4-7%.

Preferably, the functionalized boride is a mixture of boron nitride and simple boron with a mass ratio of 60-75:4-25.

Preferably, the boron nitride is a mixture of hexagonal boron nitride and cubic boron nitride with a mass ratio of 1-3:1-3; the preparation process of the functionalized boron compound is as follows: Stir and mix with cubic boron nitride, then add elemental boron, fully grind, and then bake and dry; the purity of the hexagonal boron nitride, cubic boron nitride and elemental boron is not less than 99%.

Preferably, the hydroxysilicone oil compound is a mixture of low molecular weight hydroxysilicone oil and trimethylolpropane trimethacrylate with a mass ratio of 9-13:1-2, as a composite functional agent for improving boron To improve the interfacial fusion between the compound and the silicone rubber, the hydroxyl silicone oil compound should be placed in a vacuum drying oven for 10 to 12 hours at room temperature and under the conditions of 1 to 10 kPa; the trimethylolpropane trimethacrylate contains 225ppm of hydroquinone monomethyl ether.

Preferably, the long-fiber carbon fiber is any one of commercial carbon fibers. Before use, two layers of unidirectional carbon fibers are orthogonally laid and superimposed or woven into a fabric with a pore spacing of 0.1-0.4 mm, or directly use similar Commercial fabrics are then fully impregnated with an organic solution containing a 5-10% mass concentration of hydroxy silicone oil complex and then dried.

Preferably, the commercial carbon fiber is any one of polyacrylonitrile-based carbon fiber, pitch-based carbon fiber, viscose-based carbon fiber, and phenolic-based carbon fiber.

The present invention also provides a preparation method of a high-strength silicone rubber-based flexible neutron shielding material, comprising the following steps:

Step 1. Take 45-50 parts of methyl vinyl silicone rubber or phenyl silicone rubber raw rubber with a phenyl content of 4-7% and put it into a double-bar open mill. At 40-60 ° C, add 5-6 Parts of white carbon black, kneaded for 8-10 minutes, to obtain silicone rubber base material, ready to use;

Step 2: Take hexagonal boron nitride and cubic boron nitride with a mass ratio of 1-3:1-3, stir and mix, add boron element with a total mass ratio of 60-75:4-25, and grind for 8-15 minutes , and then baked at 80～110℃ for 2～4h to obtain functionalized boride, which is ready for use;

Step 3, take low molecular weight hydroxy silicone oil and trimethylolpropane trimethacrylate with a mass ratio of 9～13:1～2, shake and stir for 5～10min, then place in a vacuum drying box at room temperature and 1～10kPa Under the condition of treatment for 10 to 12 hours, a hydroxysilicone oil compound is obtained, which is ready for use; the trimethylolpropane trimethacrylate contains 225ppm of hydroquinone monomethyl ether;

Step 4. Pre-lay 20-40 parts of unidirectional carbon fibers into two layers of orthogonally stacked or woven into fabrics or directly purchased carbon fiber fabrics and immerse them into 20-40 parts of the compound containing hydroxyl silicone oil with a mass concentration of 5-10%. After soaking for 12-16 hours in the ethanol solution of carbon dioxide, and drying at 70-80°C for 4-8 hours, the treated long-fiber carbon fiber is obtained, which is ready for use;

Step 5. By weight, take 50 parts of the silicone rubber base material and put it into a double-bar open mill, at 40 to 60 ° C, open for 3 to 5 minutes, and sequentially add 64 to 87 parts of functionalized boron compound and hydroxy silicone oil compound. 9 to 14 parts, continue to mix for 10 to 15 minutes, place the material obtained by mixing in a mold, and roll it to a single layer thickness of 0.5 under the conditions of a pressure of 100 to 150 kg.cm ^-2 and a temperature of 40 to 60 °C. ~2.0mm rubber sheet; then sandwich the pre-treated long-fiber carbon fiber between two layers of rubber sheets that have been pressed under the same conditions, and place it in the mold again for calendering under the same pressure and temperature to prepare a thickness of Sheets of about 1.0-4.0mm; after plastic-sealing the sheet, place it in a γ-ray irradiation field to keep the total absorbed dose at 30-80kGy for radiation cross-linking. After irradiation, remove the plastic seal to obtain a high-strength type Silicone rubber based flexible neutron shielding material.

Preferably, in the fifth step, the device is placed in a γ-ray irradiation field, and the placement position is selected with an absorbed dose rate of 100-300 Gy.min ^-1 .

The present invention includes at least the following beneficial effects:

(1) The present invention uses silicone rubber as a matrix, uniformly disperses the treated functionalized boride in it, calenders it into a sheet, and then laminates it with the treated long-fiber carbon fiber, and then cross-links it by gamma radiation. A high-strength silicone rubber-based flexible radiation shielding material with excellent performance is obtained; the flexible material not only has excellent neutron shielding effect, but also has excellent mechanical strength and heat resistance, and can be arbitrarily shaped according to the actual use scene. clipping.

(2) In the preparation method of the present invention, radiation crosslinking is completed at one time, the absorbed dose rate is not limited, and the absorbed dose rate of 100-300 Gy.min ^-1 is selected for the sample placement position under consideration of aging. At the same time, since the present invention adopts the radiation method to prepare without using catalyst, the obtained product has no peculiar smell, does not release substances that may cause potential safety risks or corrosion hazards to the surrounding environment or components, and has good environmental friendliness.

(3) The silicone rubber raw rubber used in the present invention is methyl vinyl silicone rubber raw rubber or phenyl silicone rubber raw rubber with moderate phenyl content, and the permanent deformation of the finished product is lower than 6.0%, so the material is also suitable as Long term filler for vertical joints, crevices or channels.

(4) In the preparation process of the present invention, the pretreated functionalized boride is used as the neutron absorber, and the finished material has good mechanical strength and temperature resistance characteristics, and its tensile strength can reach up to 34.36MPa, and the tear strength It can reach 104.36kN.m ^-1 , and the initial temperature of thermal decomposition is much higher than 350℃.

(5) The present invention controls the preparation and introduction sequence of the hydroxy silicone oil compound, so that the finished product has a certain viscosity. In the application process, the form of stacking of multi-layer sheets is also used to achieve higher requirements for shielding effectiveness. By testing the shielding effect of neutrons with a wavelength of 1.59×10 ^-10 m, it is found that the shielding effect of neutrons is higher than 99% when the thickness of the material is less than 4 mm, which achieves the intended purpose of the invention.

Other advantages, objects, and features of the present invention will appear in part from the description that follows, and in part will be appreciated by those skilled in the art from the study and practice of the invention.

Detailed ways:

The present invention will be further described in detail below with reference to the embodiments, so that those skilled in the art can implement according to the description.

It should be understood that terms such as "having", "comprising" and "including" as used herein do not assign the presence or addition of one or more other elements or combinations thereof.

Example 1:

A high-strength silicone rubber-based flexible neutron shielding material, in parts by weight, its formula includes: 100 parts of silicone rubber base material, 128 parts of functionalized boride, 20 parts of hydroxyl silicone oil compound, and 20 parts of long-fiber carbon fiber;

The preparation method of the high-strength silicone rubber-based flexible neutron shielding material includes the following steps:

Step 1. By weight, take 100 parts of phenyl silicone rubber raw rubber with a phenyl content of 4%, put it into a double-roller mill, add 10 parts of white carbon black at 50° C., and knead it for 10 minutes to obtain Silicone rubber base, ready to use;

Step 2: Take hexagonal boron nitride and cubic boron nitride with a mass ratio of 1:1, a total of 120 parts, after stirring and mixing, add 8 parts of boron element, grind for 8 minutes, and then bake at 110 ° C for 2 hours to obtain the function Boride, ready for use;

Step 3: Take 18 parts of low molecular weight hydroxysilicone oil and 2 parts of trimethylolpropane trimethacrylate, shake and stir for 5min, then place in a vacuum drying oven for 10h at room temperature and 1kPa, to obtain a hydroxysilicone oil compound, Standby; the trimethylolpropane trimethacrylate contains 225ppm of hydroquinone monomethyl ether;

Step 4: Lay 20 parts of unidirectional carbon fibers in advance into two layers and immerse them in 20 parts of an ethanol solution containing a hydroxyl silicone oil compound with a mass concentration of 10%. After soaking for 16 hours, dry at 70°C for 6 hours to obtain a well-treated product. long-fiber carbon fiber, ready for use;

Step 5. By weight, take 50 parts of the silicone rubber base material and put it into a double-bar open mill, at 40 ° C, open for 5 minutes, add 64 parts of functionalized boron compound and 9 parts of hydroxy silicone oil compound in turn, and continue to mix For 10 minutes, the material obtained by mixing was placed in a mold, and under the conditions of a pressure of 100kg.cm ^-2 and a temperature of 40°C, it was calendered into a rubber sheet with a single-layer thickness of 0.60mm, and then the pre-treated long fibers were The carbon fiber is sandwiched between two layers of rubber sheets that have been pressed under the same conditions, and is again placed in the mold for calendering under the same pressure and temperature to prepare a sheet with a thickness of about 1.20 mm; In the γ-ray irradiation field, the absorbed dose rate of 200Gy.min ^-1 was selected for the placement position, so that the total absorbed dose was kept at 80kGy for radiation cross-linking; after irradiation, the plastic seal was removed to obtain high-strength silicone rubber-based flexible neutrons. shielding material;

The performance test of the high-strength silicone rubber-based flexible neutron shielding material prepared in this example shows that the neutron shielding effect is 82.46%/1.20mm (the shielding effect is tested for neutrons with a wavelength of 1.59×10 ^-10 m) ; Tensile strength: 34.36MPa; Tear strength: 101.71kN.m ^-1 ; Permanent deformation: 2.95%;

Example 2:

A high-strength silicone rubber-based flexible neutron shielding material, in parts by weight, its formula includes: 100 parts of silicone rubber base material, 128 parts of functionalized boride, 22 parts of hydroxyl silicone oil compound, and 40 parts of long-fiber carbon fiber;

The preparation method of the high-strength silicone rubber-based flexible neutron shielding material includes the following steps:

Step 1. By weight, take 90 parts of methyl vinyl silicone rubber raw rubber and put it into a double-bar open mill, add 10 parts of white carbon black at 60 ° C, and knead for 8 minutes to obtain a silicone rubber base material, stand-by;

Step 2: Take hexagonal boron nitride and cubic boron nitride with a mass ratio of 3:1, a total of 120 parts, after stirring and mixing, add 8 parts of boron element, grind for 8 minutes, and then bake at 80 ° C for 4 hours to obtain functionalized Boride, ready for use;

Step 3: Take 18 parts of low molecular weight hydroxy silicone oil and 4 parts of trimethylolpropane trimethacrylate, shake and stir for 6 min, then place in a vacuum drying box for 12 h at room temperature and 10 kPa to obtain a hydroxy silicone oil compound, Standby; the trimethylolpropane trimethacrylate contains 225ppm of hydroquinone monomethyl ether;

Step 4: Immerse 40 parts of directly purchased carbon fiber fabrics into 40 parts of an ethanol solution containing a hydroxyl silicone oil compound with a mass concentration of 5%, soak for 12 hours, and then dry at 80° C. for 5 hours to obtain treated long-fiber carbon fibers for use. ;

Step 5. By weight, take 50 parts of the silicone rubber base material and put it into a double-bar open mill, at 40 ° C, open for 5 minutes, add 64 parts of functionalized boron compound and 10 parts of hydroxyl silicone oil compound in turn, and continue to mix 10min, put the mixed material in the mold, under the conditions of pressure 100kg.cm ^-2 and temperature 40 ℃, calender to make a single layer thickness of 1.07mm rubber sheet, and then pre-treated long fiber carbon fiber It is sandwiched between two layers of rubber sheets that have been pressed under the same conditions, and is again placed in the mold for calendering under the same pressure and temperature to prepare a sheet with a thickness of about 2.14 mm; In the irradiation field, the absorbed dose rate of 200 Gy.min ^-1 was selected for the placement position, so that the total absorbed dose was kept at 50 kGy for radiation cross-linking; after irradiation, the plastic seal was removed to obtain a high-strength silicone rubber-based flexible neutron shielding material ;

The performance test of the high-strength silicone rubber-based flexible neutron shielding material prepared in this example shows that the neutron shielding effect is 95.72%/2.14mm (the shielding effect is tested for neutrons with a wavelength of 1.59×10 ^-10 m) ; Tensile strength: 10.34MPa; Tear strength: 24.36kN.m ^-1 ; Permanent deformation: 3.58%;

Example 3:

A high-strength silicone rubber-based flexible neutron shielding material, in parts by weight, its formula comprises: 100 parts of silicone rubber base material, 174 parts of functionalized borides, 30 parts of hydroxyl silicone oil compound, and 30 parts of long-fiber carbon fiber;

The preparation method of the high-strength silicone rubber-based flexible neutron shielding material includes the following steps:

Step 1. By weight, take 90 parts of phenyl silicone rubber raw rubber with a phenyl content of 7%, put it into a double-roller mill, add 10 parts of white carbon black at 50 ° C, and knead it for 10 minutes to obtain Silicone rubber base, ready to use;

Step 2: According to the mass ratio of 1:2, take a total of 150 parts of hexagonal boron nitride and cubic boron nitride, after stirring and mixing, add 24 parts of boron element, grind for 15 minutes, and then bake at 100 ° C for 3 hours to obtain the function Boride, ready for use;

Step 3: Take 26 parts of low molecular weight hydroxy silicone oil and 4 parts of trimethylolpropane trimethacrylate, shake and stir for 10 min, and then place in a vacuum drying oven for 10 h at room temperature and 1 kPa to obtain a hydroxy silicone oil compound. use; the trimethylolpropane trimethacrylate contains 225ppm of hydroquinone monomethyl ether;

Step 4: Lay 30 parts of unidirectional carbon fibers in advance into two layers and immerse them in 25 parts of an ethanol solution containing a hydroxyl silicone oil compound with a mass concentration of 8%. After soaking for 15 hours, dry at 70°C for 4 hours to obtain a well-treated product. long-fiber carbon fiber, ready for use;

Step 5. By weight, take 50 parts of the silicone rubber base material and put it into a double-bar open mill, at 40 ° C, open for 5 minutes, add 87 parts of functionalized boron compound and 14 parts of hydroxyl silicone oil compound in turn, and continue to mix For 10 minutes, the mixed material was placed in the mold, and under the conditions of a pressure of 100kg.cm ^-2 and a temperature of 40°C, it was calendered into a single-layer rubber sheet with a thickness of 1.05mm; then the pre-treated long-fiber carbon fiber was It is sandwiched between two layers of rubber sheets that have been pressed under the same conditions, and is again placed in a mold for calendering under the same pressure and temperature to prepare a sheet with a thickness of about 2.10 mm; In the irradiation field, the absorbed dose rate of 200Gy.min ^-1 was selected for the placement position, so that the total absorbed dose was kept at 40kGy for radiation crosslinking; after irradiation, the plastic seal was removed to obtain a high-strength silicone rubber-based flexible neutron shielding material ;

The performance test of the high-strength silicone rubber-based flexible neutron shielding material prepared in this example shows that the neutron shielding effect is 97.66%/2.10mm (the shielding effect is tested for neutrons with a wavelength of 1.59×10 ^-10 m) ; Tensile strength: 29.24MPa; Tear strength: 103.21kN.m ^-1 ; Permanent deformation: 2.90%;

Example 4:

A high-strength silicone rubber-based flexible neutron shielding material, in parts by weight, its formula comprises: 100 parts of silicone rubber base material, 174 parts of functionalized boride, 30 parts of hydroxyl silicone oil compound, and 20 parts of long-fiber carbon fiber;

The preparation method of the high-strength silicone rubber-based flexible neutron shielding material includes the following steps:

Step 1, by weight, take 100 parts of methyl vinyl silicone rubber raw rubber and put it into a double-bar open mill, add 10 parts of white carbon black at 50 ° C, open and knead for 10 minutes to obtain a silicone rubber base material, stand-by;

Step 2: According to the mass ratio of 2:1, take a total of 150 parts of hexagonal boron nitride and cubic boron nitride, after stirring and mixing, add 24 parts of boron element, grind for 15 minutes, and then bake at 100 ° C for 3 hours to obtain the function Boride, ready for use;

Step 3: Take 26 parts of low molecular weight hydroxy silicone oil and 4 parts of trimethylolpropane trimethacrylate, shake and stir for 10 min, and then place in a vacuum drying oven for 10 h at room temperature and 1 kPa to obtain a hydroxy silicone oil compound. use; the trimethylolpropane trimethacrylate contains 225ppm of hydroquinone monomethyl ether;

Step 4: Immerse 20 parts of the woven carbon fiber fabric into 20 parts of an ethanol solution with a mass concentration of 10% of the hydroxysilicone oil compound, soak for 15 hours, and then dry at 70° C. for 4 hours to obtain the treated long fiber type carbon fiber, ready for use ;

Step 5. By weight, take 50 parts of the silicone rubber base material and put it into a double-bar open mill, at 40 ° C, open for 5 minutes, add 87 parts of functionalized boron compound and 14 parts of hydroxyl silicone oil compound in turn, and continue to mix 10min, put the kneaded material in the mold, under the conditions of pressure of 100kg.cm ^-2 and temperature of 40 ℃, calendered into a rubber sheet with a single layer thickness of 0.70mm, and then the pre-treated long fiber carbon fiber It is sandwiched between two layers of rubber sheets that have been pressed under the same conditions, and is again placed in a mold for calendering under the same pressure and temperature to prepare a sheet with a thickness of about 1.40 mm. After the sheet is plastic-sealed, it is placed in a γ-ray irradiation field, and the absorbed dose rate of 200 Gy.min ^-1 is selected for the placement position, so that the total absorbed dose is kept at 50 kGy for radiation cross-linking; after the irradiation is completed, the plastic seal is removed to obtain High-strength silicone rubber-based flexible neutron shielding material;

The performance test of the high-strength silicone rubber-based flexible neutron shielding material prepared in this example shows that the neutron shielding effect is 91.49%/1.40mm (the shielding effect is tested for neutrons with a wavelength of 1.59×10 ^-10 m) ; Tensile strength: 16.76MPa; Tear strength: 28.63kN.m ^-1 ; Permanent deformation: 2.68%;

Example 5:

A high-strength silicone rubber-based flexible neutron shielding material, in parts by weight, its formula includes: 100 parts of silicone rubber base material, 170 parts of functionalized boride, 28 parts of hydroxyl silicone oil compound, and 40 parts of long-fiber carbon fiber;

The preparation method of the high-strength silicone rubber-based flexible neutron shielding material includes the following steps:

Step 1. By weight, take 100 parts of methyl vinyl silicone rubber raw rubber and put it into a double-bar open mill, add 11 parts of white carbon black at 60 ° C, open and knead for 10 minutes to obtain a silicone rubber base material, stand-by;

Step 2: According to the mass ratio of 1:1, take a total of 120 parts of hexagonal boron nitride and cubic boron nitride, after stirring and mixing, add 50 parts of boron element, grind for 10 minutes, and then bake at 80 ° C for 4 hours to obtain the function Boride, ready for use;

Step 3: Take 26 parts of low molecular weight hydroxysilicone oil and 2 parts of trimethylolpropane trimethacrylate, shake and stir for 8min, then place in a vacuum drying oven for 12h at room temperature and 10kPa to obtain a hydroxysilicone oil compound, Standby; the trimethylolpropane trimethacrylate contains 225ppm of hydroquinone monomethyl ether;

Step 4: Lay 40 parts of unidirectional carbon fibers in advance into two layers and immerse them in 40 parts of an ethanol solution with a mass concentration of 10% of the hydroxy silicone oil compound. long-fiber carbon fiber, ready for use;

Step 5. By weight, take 50 parts of the silicone rubber base material and put it into a double-bar open mill, at 40 ° C, open for 5 minutes, add 85 parts of functionalized boride compound and 12 parts of hydroxyl silicone oil compound in turn, and continue to mix 10min, put the kneaded material in the mold, under the conditions of pressure of 150kg.cm ^-2 and temperature of 60 ℃, calendered into a rubber sheet with a single layer thickness of 1.80mm, and then the pre-treated long fiber carbon fiber It is sandwiched between two layers of rubber sheets that have been pressed under the same conditions, and is again placed in the mold for calendering under the same pressure and temperature to prepare a sheet with a thickness of about 3.59mm. In the irradiation field, the absorbed dose rate of 200Gy.min ^-1 was selected for the placement position, so that the total absorbed dose was kept at 30kGy for radiation crosslinking; after irradiation, the plastic seal was removed to obtain a high-strength silicone rubber-based flexible neutron shielding material ;

The performance test of the high-strength silicone rubber-based flexible neutron shielding material prepared in this example shows that the neutron shielding effect is 99.73%/3.59mm (the shielding effect is tested for neutrons with a wavelength of 1.59×10 ^-10 m) ; Tensile strength: 33.50MPa; Tear strength: 83.36kN.m ^-1 ; Permanent deformation: 3.18%;

Example 6:

A high-strength silicone rubber-based flexible neutron shielding material, in parts by weight, its formula includes: 100 parts of silicone rubber base material, 170 parts of functionalized boride, 30 parts of hydroxyl silicone oil compound, and 40 parts of long-fiber carbon fiber;

The preparation method of the high-strength silicone rubber-based flexible neutron shielding material includes the following steps:

Step 1. By weight, take 90 parts of methyl vinyl silicone rubber raw rubber and put it into a double-bar open mill, add 11 parts of white carbon black at 60 ° C, open and knead for 10 minutes to obtain a silicone rubber base material, stand-by;

Step 2. According to the mass ratio of 3:1, take a total of 120 parts of hexagonal boron nitride and cubic boron nitride, after stirring and mixing, add 50 parts of boron element, grind for 10 minutes, and then bake at 80 ° C for 4 hours to obtain the function Boride, ready for use;

Step 3: Take 26 parts of low molecular weight hydroxysilicone oil and 4 parts of trimethylolpropane trimethacrylate, shake and stir for 10min, then place in a vacuum drying box for 12h at room temperature and 10kPa to obtain a hydroxysilicone oil compound, Standby; the trimethylolpropane trimethacrylate contains 225ppm of hydroquinone monomethyl ether;

Step 4: Lay 40 parts of unidirectional carbon fibers in advance into two layers and immerse them in 40 parts of an ethanol solution with a mass concentration of 10% of the hydroxy silicone oil compound. long-fiber carbon fiber, ready for use;

Step 5. By weight, take 50 parts of the silicone rubber base material and put it into a double-bar open mill, at 40 ° C, open for 5 minutes, add 85 parts of functionalized boron compound and 13 parts of hydroxyl silicone oil compound in turn, and continue to mix 10min, put the kneaded material in the mold, under the conditions of pressure of 100kg.cm ^-2 and temperature of 40 ℃, calendered into a rubber sheet with a single layer thickness of 0.70mm, and then the pre-treated long fiber carbon fiber It is sandwiched between two layers of pressed rubber sheets, and then placed in the mold for calendering under the same pressure and temperature to prepare a sheet with a thickness of about 1.35mm. Among them, the absorbed dose rate of 200Gy.min ^-1 was selected for the placement position, and the total absorbed dose was kept at 30kGy for radiation crosslinking; after irradiation, the plastic seal was removed to obtain a high-strength silicone rubber-based flexible neutron shielding material.

The performance test of the high-strength silicone rubber-based flexible neutron shielding material prepared in this example shows that the neutron shielding effect is 94.81%/1.35mm (the shielding effect is tested for neutrons with a wavelength of 1.59×10 ^-10 m) ; Tensile strength: 27.39MPa; Tear strength: 71.78kN.m ^-1 ; Permanent deformation: 3.60%;

Example 7:

A high-strength silicone rubber-based flexible neutron shielding material, in parts by weight, its formula comprises: 100 parts of silicone rubber base material, 170 parts of functionalized boride, 29 parts of hydroxyl silicone oil compound, and 20 parts of long-fiber carbon fiber;

The preparation method of the high-strength silicone rubber-based flexible neutron shielding material includes the following steps:

Step 1. By weight, take 100 parts of methyl vinyl silicone rubber raw rubber and put it into a double-bar open mill, add 12 parts of white carbon black at 60 ° C, open and knead for 10 minutes to obtain a silicone rubber base material, stand-by;

Step 2: According to the mass ratio of 2:3, take a total of 120 parts of hexagonal boron nitride and cubic boron nitride, after stirring and mixing, add 50 parts of boron element, grind for 10 minutes, and then bake at 80 ° C for 4 hours to obtain the function Boride, ready for use;

Step 3: Take 26 parts of low molecular weight hydroxysilicone oil and 3 parts of trimethylolpropane trimethacrylate, shake and stir for 10min, then place in a vacuum drying box for 12h at room temperature and 10kPa, to obtain a hydroxysilicone oil compound, Standby; the trimethylolpropane trimethacrylate contains 225ppm of hydroquinone monomethyl ether;

Step 4: Lay 20 parts of unidirectional carbon fibers in advance into two layers and immerse them in 40 parts of an ethanol solution containing a hydroxyl silicone oil compound with a mass concentration of 5%. After soaking for 12 hours, dry at 70° C. for 4 hours to obtain a well-treated product. long-fiber carbon fiber, ready for use;

Step 5. By weight, take 50 parts of the silicone rubber base material and put it into a double-bar open mill, and at 40 ° C, open for 5 minutes, add 85 parts of functionalized boron compound and 13.5 parts of hydroxy silicone oil compound in turn, and continue to mix 15min, put the kneaded material in the mold, under the conditions of pressure of 100kg.cm ^-2 and temperature of 40 ℃, calendered into a rubber sheet with a single layer thickness of 1.12mm, and then the pre-treated long fiber carbon fiber It is sandwiched between two layers of pressed rubber sheets, and then placed in the mold for calendering under the same pressure and temperature to prepare a sheet with a thickness of about 2.24mm. , the total absorbed dose was kept at 30kGy for radiation crosslinking; after irradiation, the plastic seal was removed to obtain a high-strength silicone rubber-based flexible neutron shielding material.

The performance test of the high-strength silicone rubber-based flexible neutron shielding material prepared in this example shows that the neutron shielding effect is 98.97%/2.24mm (the shielding effect is tested for neutrons with a wavelength of 1.59×10 ^-10 m) ; Tensile strength: 27.55MPa; Tear strength: 100.17kN.m ^-1 ; Permanent deformation: 4.90%;

Although the embodiment of the present invention has been disclosed as above, it is not limited to the application listed in the description and the embodiment, and it can be applied to various fields suitable for the present invention. For those skilled in the art, it can be easily Therefore, the invention is not limited to the specific details and examples shown and described herein without departing from the general concept defined by the appended claims and the scope of equivalents.

Claims (3)

1. The high-strength silicon rubber-based flexible neutron shielding material is characterized by comprising the following components in parts by weight: 100 parts of silicone rubber base material, 128-174 parts of functionalized boride, 20-30 parts of hydroxyl silicone oil compound and 20-40 parts of long-fiber carbon fiber;

the silicone rubber base material is a mixture of raw silicone rubber and white carbon black in a mass ratio of 45-50: 5-6, and the raw silicone rubber and the white carbon black are fully kneaded before use;

the raw silicone rubber is methyl vinyl silicone rubber raw rubber or phenyl silicone rubber raw rubber with the phenyl content of 4-7%;

the functionalized boride is a mixture of boron nitride and a boron simple substance in a mass ratio of 60-75: 4-25;

the boron nitride is a mixture of hexagonal boron nitride and cubic boron nitride in a mass ratio of 1-3: 1-3; the preparation process of the functionalized boride comprises the following steps: firstly stirring and mixing hexagonal boron nitride and cubic boron nitride, then adding a boron simple substance, fully grinding, and then baking and drying; the purity of the hexagonal boron nitride, the cubic boron nitride and the boron simple substance is not lower than 99%;

the hydroxyl silicone oil compound is a mixture of low-molecular-weight hydroxyl silicone oil and trimethylolpropane trimethacrylate in a mass ratio of 9-13: 1-2; before use, the hydroxyl silicone oil compound is placed in a vacuum drying oven and treated for 10-12 hours at room temperature under the condition of 1-10 kPa; 225ppm of hydroquinone monomethyl ether is contained in the trimethylolpropane trimethacrylate;

the long-fiber carbon fiber is any one of commercial carbon fibers, two layers of unidirectional carbon fibers are orthogonally laid, overlapped or woven into a fabric with a pore space of 0.1-0.4 mm before use, and then the fabric is fully soaked in an organic solution containing 5-10% of hydroxyl silicone oil composite by mass and then dried.

2. The high-strength silicone rubber-based flexible neutron shielding material of claim 1, wherein the commercial carbon fiber is any one of polyacrylonitrile-based carbon fiber, pitch-based carbon fiber, viscose-based carbon fiber, and phenolic-based carbon fiber.

3. A preparation method of the high-strength silicon rubber-based flexible neutron shielding material as claimed in any one of claims 1 to 2 is characterized by comprising the following steps:

step one, according to parts by weight, putting 45-50 parts of methyl vinyl silicone rubber or phenyl silicone rubber raw rubber with the phenyl content of 4-7% into a double-rod open mill, adding 5-6 parts of white carbon black at 40-60 ℃, and carrying out open milling and kneading for 8-10 min to obtain a silicone rubber base material for later use;

step two, taking hexagonal boron nitride and cubic boron nitride in a mass ratio of 1-3: 1-3, stirring and mixing, adding a boron simple substance in a total mass ratio of 60-75: 4-25, grinding for 8-15 min, and then baking for 2-4 h at 80-110 ℃ to obtain a functionalized boride for later use;

step three, taking low-molecular-weight hydroxyl silicone oil and trimethylolpropane trimethacrylate with the mass ratio of 9-13: 1-2, shaking and stirring for 5-10 min, and then placing in a vacuum drying oven for treatment for 10-12 h at room temperature under the condition of 1-10 kPa to obtain a hydroxyl silicone oil compound for later use; 225ppm of hydroquinone monomethyl ether is contained in the trimethylolpropane trimethacrylate;

step four, laying 20-40 parts of unidirectional carbon fiber into two layers of orthogonal overlapped or woven fabric in advance or directly purchasing the carbon fiber fabric, soaking the carbon fiber fabric into 20-40 parts of ethanol solution containing the hydroxyl silicone oil compound with the mass concentration of 5-10%, drying for 4-8 hours at 70-80 ℃ after soaking for 12-16 hours, and obtaining treated long-fiber carbon fiber for later use;

step five, putting 50 parts by weight of silicone rubber base material into a double-roller open mill, open milling for 3-5 min at 40-60 ℃, sequentially adding 64-87 parts by weight of functionalized boride and 9-14 parts by weight of hydroxyl silicone oil compound, continuing to mix for 10-15 min, putting the mixed material into a die, and putting the die under the pressure of 100-150 kg ^-2 Calendering to prepare a rubber sheet with a single-layer thickness of 0.5-2.0 mm at the temperature of 40-60 ℃; then clamping the long-fiber carbon fiber which is processed in advance between two layers of rubber sheets which are pressed under the same conditions, placing the rubber sheets in a mould again, and calendering at the same pressure and temperature to prepare sheets with the thickness of about 1.0-4.0 mm; placing the sheet in a gamma-ray irradiation field after plastic packaging, keeping the total absorbed dose of the sheet in 30-80 kGy for radiation crosslinking, and removing the plastic packaging after irradiation to obtain the high-strength silicon rubber-based flexible neutron shielding material;

in the fifth step, the container is placed in a gamma ray irradiation field, and the placing position is selected from 100-300 Gy.min ^-1 The absorption dose rate of (c).