Preparation method of modified high-temperature-resistant smoke agent based on new electronic interference material

Abstract

The invention discloses a preparation method of a modified high-temperature-resistant smoke agent based on an electronic interference new material, and relates to the field of photoelectric countermeasure and interference, and the preparation method comprises the following steps: step 1, taking melamine polyphosphate and the electronic interference new material in a mass ratio of 1: 1, and putting into a stirring container; and 2, stirring for 1-2 hours by using a direct-current stirrer until the two materials are completely and uniformly mixed, and carrying out vacuum drying for 12-24 hours in a vacuum drying oven at 60-80 DEG C to obtain the modified high-temperature-resistant smoke agent. 3, the modified high-temperature-resistant smoke agent is placed in a sealing bag, nitrogen is introduced for storage, and temperature resistance and infrared absorption effect testing is conducted on the composite smoke agent in a muffle furnace and a smoke box subsequently. The invention has the following beneficial effects: by compounding with melamine polyphosphate, the application loss can be reduced, and the application effect can be ensured; the method has the advantages of no pollution, no chemical toxicity and low price, can realize low-cost industrial amplified production, and does not influence the infrared absorption effect and the air-suspending effect.

Description

Technical Field

[0001] The present invention relates to the field of optoelectronic countermeasure and interference, and particularly to a preparation method of a modified high-temperature resistant smoke agent based on a new material for electronic interference. Background Art

[0002] The basic principle of a smoke screen is to attenuate electromagnetic wave energy by using the reflection, absorption, scattering, and refraction characteristics of an aerosol system, so as to achieve the effects of interfering with guidance and shielding infrared imaging. Usually, a smoke screen emitted by physical means is called a cold smoke screen, which is composed of a shielding material with absorption characteristics. After spreading in the air, the formed smoke screen has an absorption effect on the infrared radiation of the target.

[0003] For a cold smoke screen, due to the high temperature of the nozzle of the smoke emitting device during release, it will cause oxidation or sintering of the smoke agent, resulting in losses and affecting the infrared shielding effect. Melamine polyphosphate, abbreviated as MPP flame retardant, has characteristics such as a high decomposition temperature, good thermal stability, no halogen, very small solubility, and low water solubility. It is one of the commonly used halogen-free flame retardant raw materials. Therefore, a preparation method of a modified high-temperature resistant smoke agent based on a new material for electronic interference is needed. Summary of the Invention

[0004] The purpose of the present invention is to make a new material for electronic interference developed by our company, which has good shielding performance for visible light and near, medium, and far infrared light, be fused with existing halogen-free flame retardants in different ways, realize the preparation of a modified high-temperature resistant smoke agent formed by mixing melamine polyphosphate and the new material for electronic interference, use a muffle furnace and a smoke chamber to test the temperature resistance ability and infrared absorption effect, and finally select the best composite scheme.

[0005] To achieve the above invention purpose, the present invention adopts the following technical scheme: A preparation method of a modified high-temperature resistant smoke agent based on a new material for electronic interference provided by the present invention includes the following steps:

[0006] Step 1: Take melamine polyphosphate and a new material for electronic interference with a mass ratio of 1:1 in a stirring container;

[0007] Step 2: Use a DC stirrer to stir for 1 - 2 hours until the two materials are completely mixed evenly, place them in a vacuum drying oven, and vacuum dry at 60°C - 80°C for 12 - 24 h to obtain a modified high-temperature resistant smoke agent;

[0008] Step 3: Store the modified high-temperature resistant smoke agent in a sealed bag filled with nitrogen for subsequent testing of the temperature resistance performance and infrared absorption effect of the composite smoke agent in a muffle furnace and a smoke chamber.

[0009] Preferably, inside the stirring container in Step 1, add anhydrous ethanol (concentration 99.5%) with the same volume as the mixture of the two materials as a dispersion solvent.

[0010] Preferably, after the mixing process in the second step ends, place the stirring container in a forced air drying oven, set the temperature to 60°C to 80°C to evaporate ethanol, and obtain a modified high-temperature resistant smoke agent.

[0011] Preferably, adjust the adding method of the electronic interference new material in the first step, which specifically includes the following steps:

[0012] (1) Add a copper salt and water into the stirring container containing melamine polyphosphate, dissolve the copper salt in the water, and continuously stir and mix using a stirrer;

[0013] (2) Nucleation process: Add a sodium hydroxide solution into the stirring container, stir at 0 to 80°C to obtain a mixed flocculent precipitate A, and add the reducing agent solution to the mixed flocculent precipitate A to obtain a precipitate B;

[0014] (3) Sulfidation process: Mechanically stir the sulfur source and the precipitate B at room temperature for 1 to 4 hours to obtain a mixed precipitate C;

[0015] (4) Oxidation process: Add a strong oxidant solution to the precipitate C, mechanically stir for 2 to 8 hours to obtain a suspension, filter the suspension to obtain a mixed precipitate D, and the mixed precipitate D is a mixture of melamine polyphosphate and the electronic interference new material;

[0016] (5) Wash and dry the mixed precipitate D, grind the dried mixed precipitate D to obtain a modified high-temperature resistant smoke agent.

[0017] Compared with the prior art, the beneficial effects of the present invention are: (1) When the cold smoke screen smoke agent is released by the smoke agent release device, the nozzle temperature is relatively high, which will cause oxidation and sintering of the smoke agent. Melamine polyphosphate can absorb a large amount of heat when decomposing and dehydrating by endothermic reaction, inhibit the temperature rise in the combustion part and its vicinity, and the decomposed water vapor in turn prevents the release of combustible gases. By compounding with the flame retardant material melamine polyphosphate, the release loss can be reduced and the release effect can be ensured; (2) The flame retardant material melamine polyphosphate and the electronic interference new material are pollution-free, non-toxic chemically, and have low prices, and can realize low-cost industrialized large-scale production; (3) The flame retardant material melamine polyphosphate itself presents a white and nearly transparent color, and the modified high-temperature resistant smoke agent formed after mixing with the electronic interference new material will not affect its infrared absorption effect; (4) Melamine polyphosphate has good air retention performance and will not affect the air retention effect of the electronic interference new material. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of a smoke box.

[0019] Figure 2 It is the test result of the smoke box of Scheme 1.

[0020] Figure 3 It is the test result of the cigarette case for Solution 2.

[0021] Figure 4 It is the test result of the cigarette case for Solution 3.

[0022] Figure 5 It is the test result of Solutions 1, 2, and 3 in the muffle furnace. Specific implementation manners

[0023] In order to enable those skilled in the art to better understand the solution of this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of this application.

[0024] A patent for a new electronic interference material (application number

[0025] ZL2024102005041) has been applied for and is pending publication, which discloses a manufacturing method of a new electronic interference material. Melamine polyphosphate is an important polymer material with the following properties:

[0026] Physical properties: Melamine polyphosphate is in the form of white crystalline powder, odorless, insoluble in water and organic solvents, has good heat resistance at high temperatures, with a specific gravity of 1.80 g / cm3, water solubility (g / 100 mL of water) < 0.15, particle size < 10.0 um, and decomposition temperature > 300 °C.

[0027] Chemical properties: Melamine polyphosphate can decompose under high-temperature conditions to produce nitrogen and moisture, and is non-toxic and harmless. It has excellent resistance to alkali, acid, and corrosion by organic solvents. Melamine polyphosphate is purchased from Baidu Aicai.

[0028] Example:

[0029] Solution 1: The stirring container selects a volume of 1 m 3For an industrial continuous mixer or an industrial-grade mixing tank, take melamine polyphosphate and a new electronic interference material with a mass ratio of 1:1 and place them in a stirring container. Take 10 Kg each in mass, and use a DC stirrer made of stainless steel to stir for 1 - 2 hours until the two materials are completely and evenly mixed (the rotation speed is set at 50 - 150 rpm). Place the mixed materials in a vacuum drying oven and vacuum dry them at 60°C - 80°C for 12 - 24 h to obtain a modified high-temperature resistant smoke agent. Take out the modified high-temperature resistant smoke agent, pour it into a sealed bag, store it by passing nitrogen, and wait for subsequent tests on the temperature resistance performance and infrared absorption effect of the modified high-temperature resistant smoke agent in a muffle furnace and a smoke chamber.

[0030] Scheme Two: Select a stirring container with a volume of 1 m 3 For an industrial continuous mixer or an industrial-grade mixing tank, take melamine polyphosphate and a new electronic interference material with a mass ratio of 1:1 and place them in a stirring container. Take 10 Kg each in mass, add anhydrous ethanol (concentration 99.5%) with the same volume as the two materials after mixing as a dispersion solvent in the stirring container, and use a DC stirrer made of stainless steel to stir for 1 - 2 hours until the two materials are completely and evenly mixed (the rotation speed is set at 50 - 150 rpm). Place the mixed materials in a vacuum drying oven and vacuum dry them at 60°C - 80°C for 12 - 24 h to obtain a modified high-temperature resistant smoke agent. Take out the modified high-temperature resistant smoke agent, pour it into a sealed bag, store it by passing nitrogen, and wait for subsequent tests on the temperature resistance performance and infrared absorption effect of the modified high-temperature resistant smoke agent in a muffle furnace and a smoke chamber.

[0031] Scheme Three: Select a stirring container with a volume of 1 m 3 For an industrial continuous mixer or an industrial-grade mixing tank, add 10 Kg of melamine polyphosphate into the inner part of the stirring container, add copper salt and water into the inner part of the stirring container, dissolve the copper salt in the water, and this process needs to be continuously stirred by a stirrer (rotation speed 50 - 150 rpm), and the stirring paddle is made of polytetrafluoroethylene material.

[0032] (2) Nucleation process: Add sodium hydroxide solution to the copper salt solution doped with the mixed materials, and stir at 0 - 80°C to obtain a mixed flocculent precipitate A; add the green reducing agent solution to the mixed flocculent precipitate A to obtain a precipitate B;

[0033] Among them, the copper salt includes Cu(NO 3 ) 2 ·3H 2 O, CuCl 2 ·2H 2 O, Cu(CH 3 COO) 2 ·H 2 O and CuSO 4, the concentration of the copper salt is 0.01 - 5 mol / L, and the concentration of the sodium hydroxide solution is 2 - 8 mol / L; the green reducing agent solution includes glucose, ascorbic acid, hydrazine hydrate, and sodium borohydride, and the concentration of the green reducing agent solution is 0.7 - 1.2 mol / L.

[0034] (3) Sulfidation process: Add the sulfur source to the precipitate B, and mechanically stir for 1 - 4 hours at room temperature to obtain a mixed precipitate C;

[0035] Among them, the sulfur source includes one or more mixtures of sodium sulfide, sodium hydrosulfide, sodium thiosulfate, and thiourea solution, and the concentration is 0.1 - 0.5 mol / L.

[0036] (4) Oxidation process: Add the strong oxidant solution to the precipitate C, and mechanically stir for 2 - 8 hours to obtain a suspension; filter the suspension to obtain a mixed precipitate D, and the mixed precipitate D is a mixture of melamine polyphosphate and the new electronic interference material;

[0037] Among them, the strong oxidant solution is one or more combinations of sulfuric acid, hydrochloric acid, nitric acid, acetic acid, and hydrogen peroxide; the stirring speed is 50 - 150 revolutions per minute, the stirring time is 1 - 4 hours, and the filtration accuracy is 0.05 - 10 microns.

[0038] (5) Wash and dry the mixed precipitate D. The washing process is to alternately wash with ultrapure water and absolute ethanol for 1 - 10 times, and finally perform vacuum drying for 12 - 24 h. Set the temperature of the vacuum drying oven to 60°C - 80°C. The dried sample is ground into fine powder to obtain the modified high-temperature resistant smoke agent.

[0039] Working principle: Store the modified high-temperature resistant smoke agent in a sealed bag filled with nitrogen for subsequent testing of the high-temperature resistance performance and infrared absorption effect of the modified high-temperature resistant smoke agent in a muffle furnace and a smoke chamber. The steps for the high-temperature resistance test in the muffle furnace are as follows:

[0040] S1: Set the heating rate of the muffle furnace to 10°C / min, the holding time to 10 min, and the holding temperature to 500°C;

[0041] S2: After waiting for the temperature of the muffle furnace to rise to 500°C, take 10 g of the smoke agent obtained by different compounding methods and copper sulfide without adding a flame retardant and place them in a porcelain boat, and then place the porcelain boat in the muffle furnace. Observe the combustion situation of the material every 1 min and continuously observe for 10 min;

[0042] S3: Record the combustion time and combustion situation while doing a good job in experimental protection.

[0043] The specific steps for testing visible light and infrared in a smoke chamber (with dimensions of 3 m × 7 m × 3 m) are as follows:

[0044] S4: Turn on the thermostatic and humidistatic air conditioner to keep the indoor space at a constant temperature and humidity;

[0045] S5: Turn on the light source, blackbody, spectrometer and infrared thermal imager. After the data is stable, record the target and background gray values of each detector before the smoke screen is released;

[0046] S6: Turn on the smoke screen spraying device, spray the smoke screen into the room while turning on the stirring fan, and after the spraying is completed, let the fan run for 10S and then turn off the stirring fan;

[0047] S7: Turn on the air concentration sampler for sampling, and at the same time record the change in the gray value of each detector after the smoke screen is sprayed.

[0048] As can be seen from the above, the performance of the modified high-temperature resistant smoke agent prepared by Scheme 1 reaches the optimum, and specific schemes can also be selected according to actual needs.

[0049] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for preparing a modified high temperature resistant smoke agent based on a new electronic interference material, characterized in that: The following steps are involved: Step 1: Place melamine polyphosphate and new electronic interference material in a mixing container at a mass ratio of 1:1; Step 2: Stirring the two materials for 1-2 hours using a DC stirrer until the two materials are completely mixed, placing the mixture in a vacuum drying oven at 60°C to 80°C for 12 to 24 hours to obtain a modified high temperature resistant smoke agent; Step 3: Place the modified high temperature resistant smoke agent in a sealed bag and store it in nitrogen, pending subsequent testing of the heat resistance and infrared absorption effect of the composite smoke agent in a muffle furnace and a smoke box.

2. According to claim 1, a method for preparing a modified high temperature resistant smoke agent based on a new electronic interference material is characterized in that: In the stirring container of step 1, anhydrous ethanol (concentration 99.5%) is added as a dispersing solvent in a volume that is the same as the volume after the two materials are mixed.

3. The method for preparing a modified high temperature resistant smoke agent based on a new electronic interference material according to claim 2, characterized in that: After the mixing process in step 2 is completed, the stirring container is placed in a blast drying oven, and the temperature is set at 60° C. to 80° C. to evaporate the ethanol, thereby obtaining a modified high temperature resistant smoke agent.

4. The method for preparing a modified high temperature resistant smoke agent based on a new electronic interference material according to claim 1, characterized in that: The method of adding the new electronic interference material in step 1 is adjusted, specifically comprising the following steps: (1) adding copper salt and water into a stirring container containing melamine polyphosphate, dissolving the copper salt in the water, and continuously stirring and mixing with a stirrer; (2) Nucleation process: adding sodium hydroxide solution into the stirring container, stirring at 0-80° C. to obtain a mixed flocculent precipitate A, and adding a reducing agent solution into the mixed flocculent precipitate A to obtain a precipitate B; (3) Sulfidation process: The sulfur source and the precipitate B are mechanically stirred at room temperature for 1 to 4 hours to obtain a mixed precipitate C; (4) Oxidation process: adding a strong oxidant solution to the precipitate C, mechanically stirring for 2 to 8 hours to obtain a suspension, filtering the suspension to obtain a mixed precipitate D, wherein the mixed precipitate D is a mixture of polyphosphate melamine and the new electronic interference material; (5) The mixed precipitate D is washed and dried, and the dried mixed precipitate D is ground to obtain a modified high temperature resistant smoke agent.

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