阅读说明：本技术 一种非分子聚合相材料及其制备方法 (Non-molecular polymeric phase material and preparation method thereof ) 是由 焦璐 刘冰冰 王鹏 刘然 刘波 郭琳琳 于 2021-01-12 设计创作，主要内容包括：本发明提供了一种非分子聚合相材料及其制备方法,属于富氮材料技术领域。本发明所述非分子聚合相材料的制备方法,包括以下步骤：将叠氮化钠粉末置于加压装置,加压至49.6～51GPa后,以45～90°为一个旋转周期,进行往复旋转,施加剪切应力,当往复旋转总角度≥405°时,停止旋转,得到非分子聚合相材料。本发明以叠氮化钠粉末为原料,在常温下利用高压和往复旋转产生的剪切应力合成非分子聚合相,能够得到纯非分子聚合相材料；本发明的方法在制备过程中无需引入其他杂质,合成压力低,工艺简单,成本低,不会污染环境,安全可靠。(The invention provides a non-molecular polymeric phase material and a preparation method thereof, belonging to the technical field of nitrogen-rich materials. The preparation method of the non-molecular polymeric phase material comprises the following steps: and (3) placing the sodium azide powder in a pressurizing device, pressurizing to 49.6-51 GPa, performing reciprocating rotation by taking 45-90 degrees as a rotation period, applying shear stress, and stopping rotation when the total reciprocating rotation angle is larger than or equal to 405 degrees to obtain the non-molecular polymeric phase material. The invention takes sodium azide powder as a raw material, synthesizes a non-molecular polymeric phase by utilizing shear stress generated by high pressure and reciprocating rotation at normal temperature, and can obtain a pure non-molecular polymeric phase material; the method of the invention does not need to introduce other impurities in the preparation process, has low synthesis pressure, simple process, low cost, no environmental pollution, safety and reliability.)

1. A method of preparing a non-molecular polymeric phase material, comprising the steps of:

and (3) placing the sodium azide powder in a pressurizing device, pressurizing to 49.6-51 GPa, applying shear stress, performing reciprocating rotation by taking 45-90 degrees as a rotation period, and stopping rotation when the total reciprocating rotation angle is larger than or equal to 405 degrees to obtain the non-molecular polymeric phase material.

2. The method of claim 1, wherein the pressing device is an unbalanced-load static high-pressure press.

3. The method according to claim 1, wherein the pressurization is performed at a rate of 4 to 5 GPa/min.

4. The method of claim 1, wherein the reciprocating rotation is at a rate of 45 °/10 s.

5. The method according to claim 1, wherein a ruby ball having a diameter of 3 μm is used as a stamp in the pressing.

6. A non-molecular polymeric phase material prepared by the method of any one of claims 1 to 5.

Technical Field

The invention relates to the technical field of nitrogen-rich materials, in particular to a non-molecular polymeric phase material and a preparation method thereof.

Background

Numerous theoretical studies have predicted that nitrogen-rich compounds are potential High Energy Density Materials (HEDMs). Since the theoretical possibility of synthesizing polymeric nitrogen structures of different morphologies has been obtained, there has been extensive interest in finding new polymeric nitrogen structures by various experimental techniques. However, since the conditions for synthesizing these polymeric nitrogens are severe, only three polymeric nitrogen structures (three-dimensional reticulated polymeric nitrogen cubic crystalline structure (cg-N), layered polymeric nitrogen layered polymeric structure (LP-N), and hexagonal layered polymeric nitrogen layered polymeric structure (HLP-N)) have been successfully synthesized. Metal-doped nitrogen-rich compounds have advantages in designing new polymeric nitrogen structures because metal-nitrogen interactions may stabilize more forms of nitrogen-rich structures relative to structures composed of pure nitrogen. The skilled person has predicted the existence of many novel nitrogen-rich structural groups, for example, caged N10, chain N8, and cyclic N5, N6 in a variety of forms.

Sodium azide (NaN)₃) Is a typical metal azide, is a white hexagonal crystal, is a colorless and tasteless solid granular crystal, and is toxic; dissolving in water (39% by mass at 0 deg.C, 40.16% by mass at 10 deg.C, and 55% by mass at 100 deg.C) and liquid ammonia (50.7% by mass at 0 deg.C), slightly dissolving in ethanol (0.3% by mass at 25 deg.C), and insoluble in diethyl ether; when heated to 40 ℃, the sodium hydroxide can be decomposed into metallic sodium and nitrogen, and a large amount of heat is released; sodium azide is explosive, has no risk of ignition, and is thermally stable as compared with other metal azides. Due to the special physical and chemical properties of the sodium azide, the sodium azide is widely applied to the fields of medicines, explosives, photo preparations, synthetic resins, pesticides, chemical synthesis, biology and the like.

The structure and the property of the material can be effectively adjusted by high-pressure shearing, and the method is a novel method for preparing the material with a novel structure and novel properties. At present, researchers have begun to explore Na N by means of high pressure₃New structures may appear in (1). NaN₃As the alkali metal azide having the highest stability, the ordinary temperature and high pressure behavior thereof has been studied intensively by Raman spectroscopy and X-ray diffraction techniques.Erem ets et al (Eremets, M.I.el., Polymerization of nitrogen in sodium azide.J.chem.Phys.2004,120,10618-10623) reported in 2004 that NaN reached 120GPa at room temperature₃Middle 1600cm^-1The azide ion tensile vibration v1 disappeared (or disappeared after shear deformation at 67 GPa), completely disappeared only at 160GPa, and it was interpreted that sodium azide was completely converted into a non-molecular polymeric phase. In 2020, the scientific scientists found (LiuBingbingel, High-Pressure-Induced Structural and Chemical Transformations in NaN3.J. Phys. chem. C.2020,124,37,19904-₃When the pressure is reduced to 21.6-57.9 GPa, part of sodium azide is dissociated and recombined to obtain sodium pentazole (NaN)₅) And sodium dinitrogen (NaN)₂). At high pressures (1 GPa), it has been experimentally found that atmospheric beta-phase sodium azide is converted to alpha-phase sodium azide. In alpha-phase sodium azide, N₃ ^-Ion perpendicular to Na⁺The planar orientation of the atoms and the weak interaction with each other, which configuration is unstable, results in a tilting of the azide chain and a transition to a monoclinic structure upon application of a pressure of several hundred bars at room temperature. However, the non-molecular polymeric phase material prepared by the prior method still contains azide groups and is not completely converted into the non-molecular polymeric phase.

Disclosure of Invention

The invention aims to provide a non-molecular polymeric phase material and a preparation method thereof.

In order to achieve the above object, the present invention provides the following technical solutions:

the invention provides a preparation method of a non-molecular polymeric phase material, which comprises the following steps:

and (3) placing the sodium azide powder in a pressurizing device, pressurizing to 49.6-51 GPa, applying shear stress, performing reciprocating rotation by taking 45-90 degrees as a rotation period, and stopping rotation when the total reciprocating rotation angle is larger than or equal to 405 degrees to obtain the non-molecular polymeric phase material.

Preferably, the pressurizing device is an unbalanced-load static high-pressure press.

Preferably, the pressurizing rate is 4-5 GPa/min.

Preferably, the rate of reciprocal rotation is 45 °/10 s.

Preferably, in the pressurizing process, a ruby ball is used as a pressure mark, and the diameter of the ruby ball is 3 μm.

The invention provides a non-molecular polymeric phase material prepared by the preparation method in the technical scheme.

The invention provides a preparation method of a non-molecular polymeric phase material, which comprises the following steps: and (3) placing the sodium azide powder in a pressurizing device, pressurizing to 49.6-51 GPa, performing reciprocating rotation by taking 45-90 degrees as a rotation period, applying shear stress, and stopping rotation when the total reciprocating rotation angle is larger than or equal to 405 degrees to obtain the non-molecular polymeric phase material. According to the invention, sodium azide powder is used as a raw material, a non-molecular polymeric phase is synthesized at normal temperature by utilizing shear stress generated by high pressure and reciprocating rotation, and the rotary shear stress generated in the reciprocating rotation process obviously reduces phase change pressure, so that a new phase is generated, and the non-molecular polymeric phase material is obtained.

The method disclosed by the invention has the advantages that other impurities are not required to be introduced in the preparation process, the synthesis pressure is low, the process is simple, the cost is low, the environment is not polluted, the safety and the reliability are realized, and the non-molecular polymeric phase can only appear when the pressure is increased to 120-160 GPa (or the shear stress is applied along one direction when the pressure is 67 GPa).

Drawings

FIG. 1 is a Raman scattering spectrum of a non-molecular polymeric phase material prepared in example 1;

FIG. 2 is a Raman scattering spectrum of a non-molecular polymeric phase material prepared in comparative example 1;

FIG. 3 is a Raman scattering spectrum of a non-molecular polymeric phase material prepared in comparative example 2.

Detailed Description

The invention provides a preparation method of a non-molecular polymeric phase material, which comprises the following steps:

and (3) placing the sodium azide powder in a pressurizing device, pressurizing to 49.6-51 GPa, performing reciprocating rotation by taking 45-90 degrees as a rotation period, applying shear stress, and stopping rotation when the total reciprocating rotation angle is larger than or equal to 405 degrees to obtain the non-molecular polymeric phase material.

In the present invention, unless otherwise specified, all the required starting materials or apparatus for the preparation are commercially available products well known to those skilled in the art.

In the invention, the pressurizing device is preferably a static high-pressure press with unbalanced load; the non-equilibrium load static high-pressure press is not particularly limited by the invention, and the corresponding device well known in the field can be used, in particular to a diamond anvil cell press, and the anvil surface of the diamond anvil cell press is 200 mu m diamond.

In the invention, the process of placing the sodium azide powder in a pressurizing device is preferably to pre-press a rhenium sheet by adopting a diamond anvil cell press, drill a hole in the center of the obtained indentation, and use the round hole obtained by drilling as a sample cavity for filling the sodium azide powder raw material; and filling excessive sodium azide powder into a round hole of the rhenium sheet, and pressurizing by taking the ruby ball as a pressure mark and taking no other medium as a pressure transmission medium. The rhenium sheet is not particularly limited in the present invention, and a rhenium sheet known in the art may be used.

In the present invention, the diameter of the circular hole drilled is preferably 66 μm; the number of the ruby balls is preferably one or two, and the diameter of the ruby ball is preferably 3 mu m; the invention uses the pressure to measure the pressure value in a diamond pressure cavity formed in the anvil cell press by the pressure measurement diamond, and determines the magnitude of the pressure value by the peak position change of the R1 fluorescence line of the ruby ball, wherein the precision is 0.1 GPa; the process of determining the magnitude of the pressure value by using the R1 fluorescence line of the ruby ball is not particularly limited in the invention, and the process can be carried out according to a labeling method and a labeling process which are well known in the field.

In the invention, the pressurizing speed is preferably 4-5 GPa/min; the rate of reciprocating rotation is preferably 45 °/10 s. The present invention is not particularly limited to the specific process of the reciprocating rotation, and the process may be performed according to a process well known in the art.

The invention provides a non-molecular polymeric phase material prepared by the preparation method in the technical scheme.

The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

Pre-pressing a rhenium sheet by using a diamond anvil press with the anvil surface of 200 mu m, drilling a round hole with the diameter of 66 mu m in the center of an indentation, wherein the round hole is used as a sample cavity for filling raw materials, filling excessive sodium azide powder into the sample cavity, adding two ruby balls with the diameter of 3 mu m as a pressure mark, adding no other medium as a pressure transmission medium, pressurizing at the speed of 4GPa/min, and rotating 405 DEG at the speed of 45 DEG every 10s and a rotation period of 45 DEG when the pressure is pressurized to 49.6GPa to obtain the non-molecular polymeric phase material.

The non-molecular polymeric phase material prepared in this example was subjected to Raman scattering testing and the results are shown in figure 1; as is clear from FIG. 1, the azide ion stretching vibration v1 disappeared, and the sodium azide decomposed and disappeared at 790cm^-1、1153.18cm^-1A new peak appears, which indicates that partial sodium azide is completely transformed into a non-molecular polymeric phase.

Comparative example 1

The press, sample chamber and sample loading were the same as in example 1; the difference from example 1 is that: pressing at a rate of 4GPa/min, rotating at a rate of 45 degrees per 10s and a rotation period of 45 degrees when pressing to 49.6GPa to obtain a material containing trace non-molecular polymeric phase.

The material prepared in this comparative example was subjected to Raman scattering testing and the results are shown in figure 2; as can be seen from FIG. 2, the azide ion stretching vibration v1 was attenuated at 854cm^-1、1157.47cm^-1A new peak with extremely weak intensity appears, which indicates that partial sodium azide is transformed into a non-molecular polymeric phase.

Comparative example 2

The press, sample chamber and sample loading were the same as in example 1; the difference from example 1 is that: the pressing was carried out at a rate of 4GPa/min, and when the pressure was increased to 49.6GPa, the material was rotated by 360 DEG at a rate of 45 DEG per 10s rotation, with 45 DEG being one rotation period, to obtain a material containing a small amount of non-molecular polymeric phase.

The material prepared in this comparative example was subjected to Raman scattering testing and the results are shown in figure 3; as can be seen from FIG. 3, the azide ion stretching vibration v1 was significantly reduced to 786cm^-1、1149cm^-1A new peak appears, which indicates that partial sodium azide is changed into a non-molecular polymeric phase.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.