CN115450046B

CN115450046B - Poly (p-phenylene benzobisoxazole) material for nuclear radiation environment protection and preparation method and application thereof

Info

Publication number: CN115450046B
Application number: CN202211100169.5A
Authority: CN
Inventors: 卜一
Original assignee: Qingdao Degan Superconducting Material Manufacturing Co ltd
Current assignee: Qingdao Degan Superconducting Material Manufacturing Co ltd
Priority date: 2022-09-08
Filing date: 2022-09-08
Publication date: 2024-04-02
Anticipated expiration: 2042-09-08
Also published as: CN115450046A

Abstract

The invention discloses a poly-p-phenylene benzobisoxazole material for nuclear radiation environment protection, a preparation method and application thereof. The method comprises the steps of uniformly combining palladium ions on the surface of a material, then reacting nickel ions with palladium ions for 2 times, improving the binding force of fibers and cloth, and then using a copper chloride solution for three times. Finally silver ammonia silver plating, the metal content reaches 30-50%, thus achieving the radiation protection function, and simultaneously being conductive, EMC and dual-purpose.

Description

Poly (p-phenylene benzobisoxazole) material for nuclear radiation environment protection and preparation method and application thereof

Technical Field

The invention relates to the field of nuclear radiation environment protection, in particular to a poly (p-phenylene benzobisoxazole) material for nuclear radiation environment protection, a preparation method and application thereof.

Background

The poly-p-Phenylene Benzobisoxazole (PBO) has the characteristics of high strength, high modulus, high heat resistance and good flame retardance due to the unique structure, has good dimensional stability and high chemical stability, is the best comprehensive performance in all the current organic fibers, is widely applied to the fields of aerospace, bullet-resistant armor protection and other technologies, military industry and national defense, and is widely applied to the civil fields of sports equipment, protective clothing and the like.

However, PBO has many excellent properties, but because there are no pendant reactive groups in the molecular structure, which renders the surface of the PBO fiber chemically inert, the interfacial adhesion of PBO fiber to other materials such as metals is poor. In addition, the ultraviolet aging phenomenon of the PBO fiber is serious, and the mechanical property of the PBO fiber is greatly reduced under the condition of overlong ultraviolet irradiation time.

The information in the background section is only for the purpose of illustrating the general background of the invention and is not to be construed as an admission or any form of suggestion that such information forms the prior art that is well known to those of ordinary skill in the art.

Disclosure of Invention

In order to solve at least part of the technical problems in the prior art, the invention provides a poly (p-phenylene benzobisoxazole) material for nuclear radiation environment protection, and a preparation method and application thereof. Specifically, the present invention includes the following.

In a first aspect of the present invention, there is provided a method for preparing a poly (p-phenylene benzobisoxazole) material for nuclear radiation environmental protection, comprising the steps of:

(1) Reacting a poly-p-phenylene benzobisoxazole material in a first reaction solution at 80-90 ℃ for 20-30 minutes to obtain a first treated material, wherein the first reaction solution contains palladium ions, stannous chloride and potassium pyrophosphate;

(2) A step of obtaining a second treatment material by allowing the first treatment material to stand in a second reaction solution at 80-90 ℃ for 30-60 minutes, wherein the second reaction solution contains nickel sulfate, citric acid, sodium hypophosphite and ammonia water;

(3) A step of reacting the second treatment material in a third reaction liquid to obtain a third treatment material, wherein the third reaction liquid contains copper chloride, sodium hydroxide, EDTA, sulfamic acid, polyethylene glycol and formaldehyde; and

(4) And (3) reacting the third treatment solution in a fourth reaction solution to obtain the required poly (p-phenylene benzobisoxazole) material, wherein the fourth reaction solution comprises silver nitrate, ammonia water and formaldehyde.

In certain embodiments, the method of preparing a poly (p-phenylene benzobisoxazole) material for nuclear radiation environmental protection according to the present invention, wherein the poly (p-phenylene benzobisoxazole) material is a fiber or cloth.

In certain embodiments, the preparation method of the poly (p-phenylene benzobisoxazole) material for nuclear radiation environmental protection according to the invention, wherein the concentration of palladium ions in the first reaction solution is 0.5-10g/L, the concentration of stannous chloride is 1-10g/L, and the concentration of potassium pyrophosphate is 1-20g/L.

In certain embodiments, the preparation method of the poly (p-phenylene benzobisoxazole) material for nuclear radiation environment protection according to the invention, wherein the concentration of nickel sulfate in the second reaction solution is 300-500g/L, the concentration of citric acid is 30-70g/L, the concentration of sodium hypophosphite is 300-500g/L, and the concentration of ammonia water is 300-500g/L.

In certain embodiments, the method for preparing the poly (p-phenylene benzobisoxazole) material for nuclear radiation environmental protection according to the present invention, wherein the third reaction solution has a copper chloride concentration of 100-200g/L, a sodium hydroxide concentration of 30-50g/L, EDTA concentration of 300-500g/L, a sulfamic acid concentration of 60-90g/L, a polyethylene glycol 6000 concentration of 1-5g/L, and a formaldehyde concentration of 10-20g/L.

In certain embodiments, the method for preparing the poly (p-phenylene benzobisoxazole) material for nuclear radiation environmental protection according to the present invention, wherein the fourth reaction solution has a silver nitrate concentration of 3-8g/L, an ammonia concentration of 1-5g/L, a sulfuric acid concentration of 0.5-5g/L and a formaldehyde concentration of 1-8g/L.

In certain embodiments, the method for preparing a poly (p-phenylene benzobisoxazole) material for nuclear radiation environmental protection according to the present invention, wherein the poly (p-phenylene benzobisoxazole) material is a material obtained by acid-treating poly (p-phenylene benzobisoxazole) fibers.

In certain embodiments, the method of preparing a poly (p-phenylene benzobisoxazole) material for nuclear radiation environmental protection according to the present invention, wherein the poly (p-phenylene benzobisoxazole) material is a poly (p-phenylene benzobisoxazole) fiber modified with PIPD.

In a second aspect of the invention, there is provided a poly-p-phenylene benzobisoxazole material for protection from nuclear radiation environments, obtainable by the process of the first aspect.

In a third aspect of the invention there is provided the use of a poly (p-phenylene benzobisoxazole) material in the protection of a nuclear radiation environment.

The method can lead the metal content in the fiber to reach 30-50 percent and even higher, thereby achieving the radiation protection effect, and simultaneously realizing the functions of conduction, EMC and dual-purpose.

Detailed Description

Various exemplary embodiments of the invention will now be described in detail, which should not be considered as limiting the invention, but rather as more detailed descriptions of certain aspects, features and embodiments of the invention.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In addition, for numerical ranges in the present invention, it is understood that the upper and lower limits of the ranges and each intermediate value therebetween are specifically disclosed. Every smaller range between any stated value or stated range, and any other stated value or intermediate value within the stated range, is also encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control. Unless otherwise indicated, "%" is percent by weight.

As used herein, the term "nuclear radiation environment protection" refers to the ability to attenuate and block at least a portion of radiation from passing through a layer of material in a nuclear radiation environment. Here, the nuclear radiation environmental protection is achieved by plating the fiber surface with a metal layer. The nuclear radiation environment protection in the invention is realized mainly by a silver metal layer.

As used herein, the term "poly (p-phenylene benzobisoxazole) material" means PBO fibers or cloth or sheet materials further prepared therefrom. Wherein the PBO fiber means a fiber made of poly (p-phenylene benzobisoxazole) or a modified fiber made of poly (p-phenylene benzobisoxazole) as a main body.

As used herein, the term "modified fiber" refers generally to a PBO/PIPD composite fiber prepared by adding a [2, 5-dihydroxy-1, 4-phenylene pyridobisimidazole ] (PIPD) polymer during PBO polymerization. The composite fiber has improved microfibrillation and can increase the amount of active groups on the fiber surface, thereby facilitating metal plating. The amount of PIPD added to the conjugate fiber is generally 30% or less, preferably 20% or less, more preferably 10% or less, such as 5% or 3% or the like, based on the weight. If the amount of PIPD added is too high, the strength of the composite fiber tends to decrease. On the other hand, if the amount of PIPD added is too low, the modifying effect of the conjugate fiber is poor.

The term "acid treated PBO fibers" as used herein refers to treatment of PBO fibers with an acid solution to enhance the metal plating effect and to enhance the aging resistance. The type of acid in the acid treatment is not limited and may be any known acid including organic acids, inorganic acids, examples of which include but are not limited to hydrochloric acid, sulfuric acid, nitric acid, acetic acid, and the like. The concentration of the acid in the acid solution is not particularly limited, and is generally a weak acid solution, for example, the acid concentration is 1 to 30%, preferably 20% or less, more preferably 15% or less. If the acid concentration is too high, the solubility to PBO is greater, affecting the fiber strength and even completely degrading the fiber. If the acid concentration is too low, the improvement of the metal plating effect is insufficient. The reason why the acid treatment improves the metal plating effect may be that the acid treatment can moderately microfibrillate the fiber, and the metal after microfibrillation is plated not only on the surface of the fiber but also can penetrate into the inside of the fiber to thereby improve the nuclear protection ability of the fiber. The acid treatment time is generally 1 to 10 hours, preferably 2 to 6 hours, more preferably 3 to 5 hours.

[ preparation method ]

In a first aspect of the present invention, there is provided a process for the preparation of a poly (p-phenylene benzobisoxazole) material for protection from the nuclear radiation environment, including, but not limited to, the steps of:

It will be appreciated by those skilled in the art that the numbers (1), (2), etc. are for the purpose of distinguishing between different steps only and do not indicate the sequential order of the steps. The order of the steps is not particularly limited as long as the object of the present invention can be achieved. In addition, it will be appreciated by those skilled in the art that other steps or operations may be included before or after steps (1) - (4) or between any of these steps, such as further optimizing and/or improving the methods described herein. The steps are described below

Step (1)

The step (1) of the present invention is a step of forming reduced palladium particles on the surface of a fiber, and comprises a step of reacting a poly-p-phenylene benzobisoxazole material in a first reaction liquid at 80 to 90 ℃ for 20 to 30 minutes to obtain a first treated material. The palladium can be reduced and bonded to the surface of the fiber without using a sensitization solution through the step (1), and an activation center is formed on the surface, so that the subsequent electroless plating reaction is initiated.

In the present invention, the first reaction liquid contains palladium ions, stannous chloride and potassium pyrophosphate. Among them, palladium ions may be provided by palladium chloride or the like. The concentration of palladium chloride is generally from 0.5 to 10g/L, preferably from 1 to 8g/L, more preferably from 2 to 5g/L. The concentration of stannous chloride is generally in the range of 1 to 10g/L, preferably 2 to 8g/L, more preferably 3 to 5g/L. The concentration of potassium pyrophosphate is generally 1 to 20g/L, preferably 2 to 15g/L, more preferably 5 to 10g/L.

Step (2)

The step (2) of the invention is to form a nickel metal layer on the surface of the fiber, and comprises the step of obtaining a second treatment material by the first treatment material in a second reaction solution at 80-90 ℃ for 30-60 minutes. The step (2) is used for further improving the binding force between the metallic silver layer and the fiber, and the plating amount of nickel is not excessively high.

In the invention, the second reaction solution comprises nickel sulfate, citric acid, sodium hypophosphite and ammonia water. Wherein the concentration of nickel sulfate is generally 300-500g/L, preferably 350-450g/L. The concentration of citric acid is generally 30 to 70g/L, preferably 35 to 65g/L, more preferably 40 to 50g/L. The concentration of sodium hypophosphite is generally 300-500g/L, preferably 350-450g/L, more preferably 400-450g/L. The concentration of the aqueous ammonia is generally 300 to 500g/L, preferably 350 to 450g/L, more preferably 400 to 450g/L.

Step (3)

The step (3) of the present invention is a step of further plating a copper layer, and includes a step of reacting the second treatment material in a third reaction liquid to obtain a third treatment material.

It should be noted that, step (3) of the present invention is used to form the primer layer, so that strict control of the reaction is required to avoid the influence of forming a thicker copper layer on the material properties, particularly the protective properties. For this purpose, the reaction can be controlled so that it is terminated when the conductivity of the material reaches 30-50 ohm per cm. The lower the conductivity, the more copper that forms on the surface, affecting the material properties. On the other hand, the higher the conductivity, the less copper formed on the surface, which is detrimental to silver bonding.

In the invention, the third reaction liquid comprises copper chloride, sodium hydroxide, EDTA, sulfamic acid, polyethylene glycol and formaldehyde. The concentration of copper chloride in the third reaction liquid is generally 100 to 200g/L, preferably 120 to 180g/L, and more preferably 130 to 160g/L. The concentration of sodium hydroxide is generally 30 to 50g/L, preferably 35 to 45g/L, more preferably 35 to 40g/L. The concentration of EDTA is generally 300 to 500g/L, preferably 350 to 450, more preferably 350 to 400g/L. The concentration of sulfamic acid in the present invention is generally 60 to 90g/L, preferably 65 to 85g/L, more preferably 70 to 80g/L. In the present invention, the concentration of polyethylene glycol 6000 is generally 1 to 5g/L, preferably 2 to 4g/L, more preferably 3 to 4g/L. The concentration of formaldehyde in the present invention is generally 10 to 20g/L, preferably 12 to 18g/L, more preferably 15 to 16g/L.

Step (4)

The step (4) of the invention is a step of plating a silver layer and comprises a step of reacting the third treatment liquid in a fourth reaction liquid to obtain the required poly-p-phenylene benzobisoxazole material.

In the invention, the fourth reaction solution is silver-ammonia solution, which contains silver nitrate, ammonia water and formaldehyde. Wherein the concentration of silver nitrate is generally 3-8g/L, preferably 4-6g/L. The concentration of the aqueous ammonia is generally 1 to 5g/L, preferably 2 to 4g/L. The concentration of sulfuric acid is generally 0.5 to 5g/L, preferably 1 to 4g/L, more preferably 2 to 3g/L. The concentration of formaldehyde is generally 1 to 8g/L, preferably 2 to 6g/L, more preferably 3 to 5g/L.

Example 1

In the embodiment, the material for nuclear radiation environment protection is prepared by taking the poly-p-phenylene benzobisoxazole fiber as a raw material.

1. Palladium chloride 3g/L, stannous chloride 5g/L and potassium pyrophosphate 10g/L are reacted for 20-30 minutes at the temperature of 80 ℃ to ensure that palladium particles are uniformly combined on the surface of the fiber.

2. The reaction was carried out at 85℃for 20 minutes with 450g/L of nickel sulfate, 50g/L of citric acid, 400g/L of sodium hypophosphite and 400g/L of ammonia water. The bonding force between nickel and fiber is improved by 2 times of reaction between nickel ions and palladium particles.

3. Adding the fiber obtained in the step 2 into a solution of 150g/L copper chloride, 40g/L, EDTA g/L sodium hydroxide, 75g/L sulfamic acid, 6000 g/L polyethylene glycol and 15g/L formaldehyde for three reactions.

4. Silver nitrate 5g/L, ammonia water 2g/L and formaldehyde 4g/L are used to uniformly distribute mixed metal in the fiber, and the reaction time is controlled to make the metal content reach 30wt%.

Example 2

In the embodiment, the material for nuclear radiation environment protection is prepared by taking cloth prepared from the poly-p-phenylene benzobisoxazole fiber as a raw material.

1. 3g/L of palladium chloride, 5g/L of stannous chloride and 10g/L of potassium pyrophosphate are used for reaction for 20-30 minutes at the temperature of 85 ℃ so that palladium particles are uniformly combined on the surface of the fiber cloth.

2. The reaction is carried out for 60 minutes at the temperature of 90 ℃ by using 450g/L nickel sulfate, 50g/L citric acid, 400g/L sodium hypophosphite and 400g/L ammonia water, so that enough nickel metal is formed on the surface fibers of the cloth and the surfaces of the internal fibers.

4. Silver nitrate 5g/L, ammonia water 2g/L and formaldehyde 4g/L are used to uniformly distribute mixed metal in the fiber, and the reaction time is controlled to ensure that the metal content reaches 35wt%.

Example 3

In the embodiment, PBO/PIPD composite fiber (weight ratio of 99:1) is used as a raw material to prepare a material for nuclear radiation environment protection.

Example 4

In the embodiment, the material for nuclear radiation environment protection is prepared by using the fiber obtained by treating PBO fiber with 10% sulfuric acid for 3 hours as a raw material.

4. Silver nitrate 5g/L, ammonia water 2g/L and formaldehyde 4g/L are used to uniformly distribute mixed metal in the fiber, and the reaction time is controlled to make the metal content reach 40wt%.

Test case

The raw materials that were not subjected to the metal plating treatment of the present invention, namely, the poly-p-phenylene benzobisoxazole fibers, the PBO/PIPD composite fibers (weight ratio 99:1), and the 10% sulfuric acid treated PBO fibers were compared. The performance of the inventive examples and the raw materials for comparison were tested as follows, and the results are shown in table 1.

1. Tensile Strength

The individual fibers were subjected to a monofilament tensile test using a universal electronic tensile tester with the test standard ASTM-D3379 method for testing tensile Strength and Young's modulus of high modulus monofilament materials. Specifically, 100mm×20mm coordinate paper was cut, and fibers were stuck in the middle of the blank area in the middle of the coordinate paper, and the diameter of the fibers was measured. The sample was clamped to the clamp of the tensile tester and the two edge areas of the paper frame were cut to retain the fibers. And recording a displacement-force value curve obtained by testing the sample, and obtaining a maximum force value P and a fracture displacement Deltal of the tested fiber sample. From this, the monofilament tensile strength of the fiber was calculated.

2. Ultraviolet aging test

Each fiber was subjected to uv aging treatment to test its uv resistance and compared. The ultraviolet aging box has 6 ultraviolet lamp tubes with power of 40 w/branch and length of 60cm. The ultraviolet irradiation time was 48 hours.

3. X-ray protection experiment

Cloth was prepared from each fiber under the same conditions, with 10 layers of cloth laminate as the test material. Ensuring that the test material laminates are tightly laminated without defects such as voids, cracks, bubbles, blemishes, foreign matter, and uneven thickness.

Under the same irradiation condition, the thickness of the lead layer with the same shielding capacity as the tested protective material, namely the lead equivalent weight, represents the protective performance. The lead equivalent of the sample was measured using a standard lead sheet substitution method. For the sample measurement, no less than 3 points are used at a time, an average value is taken, and each point is repeated 3 times. Take the lowest value.

TABLE 1

While the invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. Various modifications or changes may be made to the exemplary embodiments of the present disclosure without departing from the scope or spirit of the invention. The scope of the claims is to be accorded the broadest interpretation so as to encompass all modifications and equivalent structures and functions.

Claims

1. The preparation method of the poly (p-phenylene benzobisoxazole) material for nuclear radiation environment protection is characterized by comprising the following steps of:

treating the poly (p-phenylene benzobisoxazole) material for 2-6 hours by using a weak acid solution with the acid concentration of 1-15% to obtain the treated poly (p-phenylene benzobisoxazole) material;

reacting the acid-treated poly-p-phenylene benzobisoxazole material in a first reaction solution at 80-90 ℃ for 20-30 minutes to obtain a first treated material, wherein the first reaction solution contains 0.5-10g/L palladium ions, 1-10g/L stannous chloride and 1-20g/L potassium pyrophosphate;

a step of obtaining a second treatment material by allowing the first treatment material to stand in a second reaction solution at 80-90 ℃ for 30-60 minutes, wherein the second reaction solution contains nickel sulfate, citric acid, sodium hypophosphite and ammonia water;

a step of reacting the second treatment material in a third reaction liquid to have a material conductivity of 30 to 50 ohms per cm, thereby obtaining a third treatment material, wherein the third reaction liquid contains copper chloride, sodium hydroxide, EDTA, sulfamic acid, polyethylene glycol, and formaldehyde; and

and the third treatment material is reacted in a fourth reaction solution to obtain the required poly-p-phenylene benzobisoxazole material, wherein the fourth reaction solution contains silver nitrate, ammonia water and formaldehyde.

2. The method for preparing a poly-p-phenylene benzobisoxazole material used for nuclear radiation environmental protection as claimed in claim 1, wherein the poly-p-phenylene benzobisoxazole material is a fiber or cloth.

3. The method for producing a poly-p-phenylene benzobisoxazole material used for the protection of nuclear radiation environment according to claim 1, wherein the concentration of nickel sulfate in the second reaction liquid is 300 to 500g/L, the concentration of citric acid is 30 to 70g/L, the concentration of sodium hypophosphite is 300 to 500g/L, and the concentration of ammonia water is 300 to 500g/L.

4. The method for producing a poly (p-phenylene benzobisoxazole) material for nuclear radiation environmental protection according to claim 1, wherein the third reaction liquid has a copper chloride concentration of 100 to 200g/L, a sodium hydroxide concentration of 30 to 50g/L, EDTA concentration of 300 to 500g/L, a sulfamic acid concentration of 60 to 90g/L, a polyethylene glycol 6000 concentration of 1 to 5g/L and a formaldehyde concentration of 10 to 20g/L.

5. The method for producing a poly-p-phenylene benzobisoxazole material used for the protection of nuclear radiation environment according to claim 1, wherein the concentration of silver nitrate in the fourth reaction liquid is 3 to 8g/L, the concentration of ammonia water is 1 to 5g/L, the concentration of sulfuric acid is 0.5 to 5g/L, and the concentration of formaldehyde is 1 to 8g/L.

6. The method for preparing a poly (p-phenylene benzobisoxazole) material for nuclear radiation environmental protection as claimed in claim 1, wherein the poly (p-phenylene benzobisoxazole) material is poly (p-phenylene benzobisoxazole) fiber modified with PIPD.

7. A poly-p-phenylene benzobisoxazole material for nuclear radiation protection, obtainable by the preparation process of any of claims 1 to 6.

8. Use of the poly-p-phenylene benzobisoxazole material as defined in claim 7 in nuclear radiation environmental protection.