阅读说明：本技术 一种低热膨胀材料及其制备方法和应用 (Low-thermal-expansion material and preparation method and application thereof ) 是由 陈骏 张娅 施耐克 宋玉柱 刘辉 于 2021-08-27 设计创作，主要内容包括：本发明实施例公开一种低热膨胀材料及其制备方法和应用,属于低热膨胀材料技术领域。本发明的低热膨胀材料包括氰胺锌。将锌盐、氰胺盐、氨水加入水中后,反应,后处理,制得所述氰胺锌。本发明的低热膨胀材料温度区间宽,在N-(2)氛围下-150℃-800℃范围内不分解,在空气氛围下-150℃-375℃范围内不分解,可长期稳定存在,其重量随着温度的变化只有微弱改变,是理想的低热膨胀材料。本发明的低热膨胀材料的成本低廉,制备工艺简单,制备规模可控,有望大规模合成。(The embodiment of the invention discloses a low thermal expansion material and a preparation method and application thereof, belonging to the technical field of low thermal expansion materials. The low thermal expansion material of the present invention comprises zinc cyanamide. Adding zinc salt, cyanamide salt and ammonia water into water, reacting, and performing post-treatment to obtain the cyanamide zinc. The low thermal expansion material of the invention has a wide temperature range of N 2 The material does not decompose in the range of-150 ℃ to 800 ℃ in the atmosphere, does not decompose in the range of-150 ℃ to 375 ℃ in the air atmosphere, can exist stably for a long time, has only slight change along with the change of temperature, and is an ideal low-thermal expansion material. The low-thermal expansion material has low cost, simple preparation process and controllable preparation scale, and is expected to be synthesized on a large scale.)

1. A low thermal expansion material, characterized in that the low thermal expansion material comprises zinc cyanamide.

2. The method for producing a low thermal expansion material according to claim 1,

adding zinc salt, cyanamide salt and ammonia water into water, reacting, and performing post-treatment to obtain the cyanamide zinc.

3. The method for producing a low thermal expansion material according to claim 1,

the zinc salt is selected from one or a combination of zinc chloride, zinc nitrate, zinc chloride dihydrate, zinc chloride tetrahydrate and zinc nitrate hexahydrate.

4. The method for producing a low thermal expansion material according to claim 1,

the cyanamide salt is selected from cyanamide.

5. The method for producing a low thermal expansion material according to claim 1,

the mass ratio of the zinc salt to the cyanamide salt to the ammonia water is 1: 0.4-1.5: 1.8 to 4, preferably 1: 0.4-1: 1.8-3.5.

6. The method for producing a low thermal expansion material according to claim 1,

in the reaction system, the concentration of the zinc salt is 0.04 wt% to 0.15 wt%.

7. The method for producing a low thermal expansion material according to claim 1,

the concentration of the ammonia water is 12.5 wt% -25 wt%.

8. The method for producing a low thermal expansion material according to claim 1,

the reaction time is 3 to 10 hours.

9. The method for producing a low thermal expansion material according to claim 1,

the post-treatment comprises the steps of filtering, washing and vacuum drying;

the vacuum drying temperature is 50-100 deg.C, and the drying time is more than 5 hr.

10. Use of a low thermal expansion material according to claim 1.

Technical Field

The invention belongs to the technical field of low-thermal-expansion materials, and relates to a low-thermal-expansion material, and a preparation method and application thereof.

Background

The low thermal expansion material has high research space and wide application field, and the volume of the low thermal expansion material is only slightly changed or even not changed along with the change of temperature, so that the low thermal expansion material is used for reducing and solving the problems of device failure, damage and the like caused by expansion with heat and contraction with cold or mismatch of thermal expansion coefficients, thereby stabilizing the performance.

The low thermal expansion material can be applied to important fields from ovens to refrigerated cookers, electronic equipment, heat engine components, automobiles, integrated circuit boards, aerospace materials and the like, and the low thermal expansion performance can ensure that micro cracks can not be generated when the operating thermal environment of the product is changed.

However, the low thermal expansion materials available in the market are few and the temperature range is small, so it is very urgent to develop a low thermal expansion material with wide temperature range.

Disclosure of Invention

The invention solves the technical problems that less low-thermal expansion materials can be utilized in the market at present and the temperature range is small. The low thermal expansion material of the invention has a wide temperature range of N₂The catalyst does not decompose in the range of-150 ℃ to 800 ℃ in the atmosphere, does not decompose in the range of-150 ℃ to 375 ℃ in the air atmosphere, and can exist stably for a long time. The low-thermal expansion material has low cost, simple preparation process and controllable preparation scale, and is expected to be synthesized on a large scale.

In order to solve the technical problems, the invention provides the following technical scheme:

it is an object of the present invention to provide a low thermal expansion material comprising zinc cyanamide.

The low thermal expansion material can be compounded with other conventional low thermal expansion materials or negative thermal expansion materials to be used as the low thermal expansion material together.

Another object of the present invention is to provide a method for producing a low thermal expansion material,

adding zinc salt, cyanamide salt and ammonia water into water, reacting, and performing post-treatment to obtain the cyanamide zinc.

Preferably, the first and second liquid crystal materials are,

the zinc salt is selected from one or a combination of zinc chloride, zinc nitrate, zinc chloride dihydrate, zinc chloride tetrahydrate and zinc nitrate hexahydrate.

Preferably, the first and second liquid crystal materials are,

the cyanamide salt is selected from the group consisting of Cyanamide (CH)₂N₂)。

Preferably, the first and second liquid crystal materials are,

the mass ratio of the zinc salt to the cyanamide salt to the ammonia water is 1: 0.4-1.5: 1.8 to 4, preferably 1: 0.4-1: 1.8-3.5.

Preferably, the first and second liquid crystal materials are,

in the reaction system, the concentration of the zinc salt is 0.04 wt% to 0.15 wt%.

Preferably, the first and second liquid crystal materials are,

the concentration of the ammonia water is 12.5 wt% -25 wt%.

Preferably, the first and second liquid crystal materials are,

the reaction time is 3-10 hours.

Preferably, the first and second liquid crystal materials are,

the post-treatment comprises the steps of filtering, washing and then carrying out vacuum drying; whether or not grinding after vacuum drying does not affect the use of zinc cyanamide as a low thermal expansion material, but is a bulk solid before grinding.

The vacuum drying temperature is 50-100 deg.C, and the drying time is more than 5 hr.

It is a further object of the present invention to provide the use of a low thermal expansion material which is one of the objects of the present invention.

The low thermal expansion material of the invention can be applied to important fields such as cookers from ovens to freezes, electronic equipment, heat engine components, automobiles, integrated circuit boards, aerospace materials and the like.

The technical scheme provided by the embodiment of the invention at least has the following beneficial effects:

the invention makes up the problem of lack of low thermal expansion performance materials and develops a material zinc cyanamide with low thermal expansion performance.

The low thermal expansion material of the invention has a wide temperature range of N₂The catalyst does not decompose in the range of-150 ℃ to 800 ℃ in the atmosphere, does not decompose in the range of-150 ℃ to 375 ℃ in the air atmosphere, and can exist stably for a long time. The low-thermal expansion material has low cost, simple preparation process and controllable preparation scale, and is expected to be synthesized on a large scale.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is an XRD pattern of zinc cyanamide compound prepared by the present invention.

FIG. 2 is a graph of the relationship between the a axis of a cyanamide zinc compound prepared by the present invention and the temperature.

FIG. 3 is a graph of the relationship between b-axis and temperature of cyanamide zinc compound prepared by the present invention.

FIG. 4 is a graph of the relationship between the c-axis of a zinc cyanamide compound prepared by the present invention and temperature.

FIG. 5 is a graph showing the relationship between unit cell volume and temperature of zinc cyanamide compound prepared by the present invention.

FIG. 6 shows the preparation of zinc cyanamide compound in N₂TG-DSC diagram under atmosphere.

Detailed Description

In order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.

Example 1

The preparation method of the low thermal expansion material comprises the following steps:

adding zinc chloride, cyanamide and ammonia water (the concentration is 24 wt%) into water to prepare a mixed solution, wherein the mass ratio of the zinc chloride to the cyanamide to the ammonia water is 1: 0.4: 1.8, the concentration of zinc chloride is 0.05 wt%; and then reacting for 5 hours under the condition of stirring, filtering during post-treatment, washing a reaction product by using distilled water, drying for 6 hours in vacuum at 70 ℃, cooling and grinding to obtain the zinc cyanamide.

Example 2

The preparation method of the low thermal expansion material comprises the following steps:

adding zinc nitrate, cyanamide and ammonia water (the concentration is 18 wt%) into water to prepare a mixed solution, wherein the mass ratio of zinc chloride to cyanamide to ammonia water is (1): 1: 3, the concentration of the zinc nitrate is 0.1 wt%; and then reacting for 6 hours under the condition of stirring, filtering during post-treatment, washing a reaction product by using distilled water, drying for 5 hours at 80 ℃ in vacuum, cooling and grinding to obtain the zinc cyanamide.

Example 3

The preparation method of the low thermal expansion material comprises the following steps:

adding zinc chloride dihydrate, cyanamide and ammonia water (the concentration is 12.5 wt%) into water to prepare a mixed solution, wherein the mass ratio of the zinc chloride to the cyanamide to the ammonia water is 1: 1.5: 4, the concentration of zinc chloride dihydrate is 0.15 wt%; and then reacting for 3 hours under the condition of stirring, filtering during post-treatment, washing a reaction product by using distilled water, drying for 10 hours in vacuum at 50 ℃, cooling and grinding to obtain the zinc cyanamide.

The performance test data for zinc cyanamide prepared in example 1 is as follows:

fig. 1 is an XRD pattern of zinc cyanamide compound prepared by the present invention, and it can be seen from fig. 1 that zinc cyanamide is a single phase, i.e. the synthesized zinc cyanamide is pure and has no other impurities. This indicates that the low thermal expansion performance of the zinc cyanamide tested in fig. 2-6 is the intrinsic property of zinc cyanamide and is not affected by other substances.

Fig. 2-4 are graphs showing the changes of the a, b and c axes of the zinc cyanamide compound prepared by the present invention with temperature, fig. 5 is a graph showing the relationship between the unit cell volume of the zinc cyanamide compound prepared by the present invention and the temperature, and the corresponding test data in fig. 2-5 are shown in table 1. It can be seen that the zinc cyanamide compound prepared by the invention has strong low thermal expansion Coefficient (CTE) of +2.74 multiplied by 10 at-150 ℃ to 50 DEG C^-6K^-1. 50 ℃ to 200 ℃ and exhibits positive expansion with a CTE of + 8.48X 10^-6K^-1. Therefore, the volume of the zinc cyanamide compound prepared by the invention is only slightly changed along with the change of temperature, and the zinc cyanamide compound is an ideal low-thermal expansion material.

TABLE 1

T	a	b	c	V
					200	8.81294	8.81294	5.43109	421.82082
150	8.81035	8.81035	5.43148	421.60346
					100	8.80808	8.80808	5.43187	421.41644
50	8.80635	8.80635	5.4323	421.28489
					0	8.80487	8.80487	5.43273	421.17639
-50	8.80376	8.80376	5.43332	421.11535
					-100	8.80282	8.80282	5.43393	421.07325
-150	8.8021	8.8021	5.43458	421.05443

FIG. 6 shows the preparation of zinc cyanamide compound in N₂TG-DSC diagram under atmosphere, it can be seen that in N₂The zinc cyanamide can stably exist at the temperature of 800 ℃ under the atmosphere, the weight of the zinc cyanamide is only slightly changed along with the change of the temperature, and the zinc cyanamide is an ideal low-thermal expansion material.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.