Method for preparing Fe / SiO2 material with nano multilayer composite membrane structure by organic release membrane method
The preparation of Fe/SiO2 materials with a nano-multilayer composite membrane structure by the organic release membrane method solves the problems of complex and high cost in the preparation of carbonyl iron powder in the existing technology, and achieves good absorption effect in the microwave frequency range and cost reduction.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-27
- Publication Date
- 2026-03-31
AI Technical Summary
Existing carbonyl iron powder preparation processes are complex and costly, with narrow absorption bandwidth and high density, which limits its application in microwave absorbing materials.
The organic release membrane method was used to alternately deposit nano-multilayer Fe/SiO2 composite films on a soluble thin film substrate by chemical vapor deposition. Subsequently, the substrate was peeled off, ultrasonically crushed and centrifuged to obtain the nano-multilayer composite film structure Fe/SiO2 material.
A continuous fabrication process was achieved, allowing for precise control of film thickness and the number of layers. This improved the absorption of microwaves in the 2-18 GHz frequency range and reduced process costs.
Smart Images
Figure CN121772206A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of shielding materials, and in particular to a method for developing a nano-multilayer composite film structure Fe / SiO2 material. Background Technology
[0002] Electromagnetic wave absorbing materials, or wave-absorbing materials, are one of the important materials for weaponry. Wave-absorbing materials are a class of materials that can absorb the energy of electromagnetic waves projected onto their surface and convert it into heat energy through material losses. Magnetic wave-absorbing materials absorb electromagnetic waves through hysteresis loss, eddy current loss, and residual loss. Furthermore, since most magnetic materials also possess free electron absorption magnetic loss, they have better wave-absorbing performance. Among magnetic wave-absorbing materials, carbonyl iron powder has advantages such as high saturation magnetization, strong stability, and good dispersibility compared to other wave-absorbing matrices. Currently, the carbonyl iron powder prepared is mainly obtained by decomposing pentacarbonyl iron, and the powder is mostly spherical. It requires multiple processes such as mixing, planetary ball milling, drying, and sieving to obtain the sheet-like Fe / SiO2 composite material used as a wave-absorbing material. However, it still suffers from problems such as narrow absorption bandwidth, high density, and high cost, which greatly limits its application.
[0003] This invention employs a novel process to directly prepare Fe / SiO2 nano-multilayer composite film structures, which can be used as microwave absorbing materials to improve their microwave absorption performance and reduce process costs. Summary of the Invention
[0004] The purpose of this invention is to provide a method for preparing Fe / SiO2 nanoscale multilayer composite film structure materials using an organic release membrane method, thereby obtaining multilayer composite film structure Fe / SiO2 materials that can be used as microwave absorbing materials to improve their microwave absorption performance and reduce process costs.
[0005] To achieve the above objectives, the following technical solutions are provided:
[0006] A method for preparing Fe / SiO2 nanoscale multilayer composite membrane structure using an organic release membrane method includes the following steps: (1) Iron pentacarbonyl and hexamethyldioxane were heated to evaporate and deposited alternately on a soluble thin film substrate under vacuum conditions by chemical vapor deposition to form a nano-multilayer Fe / SiO2 composite film. (2) Dissolve the soluble film substrate with a solvent to peel the nano-multilayer Fe / SiO2 composite film off from the substrate, and obtain a solid-liquid mixture containing Fe / SiO2 composite film fragments; (3) The solid-liquid mixture is subjected to ultrasonic pulverization, centrifugal separation and drying to obtain a nano-multilayer composite film structure Fe / SiO2 material.
[0007] In step (1), a multilayer Fe / SiO2 composite film is deposited on a moving soluble thin film substrate.
[0008] In step (1), the deposition is carried out alternately on the soluble thin film substrate under vacuum conditions. A roll-up multi-chamber vacuum deposition equipment is used, with the first and last chambers being SiO2 deposition chambers and Fe deposition chambers arranged between the SiO2 deposition chambers. The total number of deposition chambers is odd.
[0009] In step (1), the soluble film substrate is an alcohol-soluble phenolic resin film.
[0010] In step (1), the total number of layers of the nano-multilayer Fe / SiO2 composite film is odd, the surface layer and the bottom layer are SiO2 layers, and the Fe layers are spaced between each SiO2 layer.
[0011] In step (2), the solvent may be ethanol or n-butanol.
[0012] In step (3), the solid-liquid mixture is filtered, ultrasonically pulverized, centrifuged and dried, including: first, the Fe / SiO2 composite membrane fragments in the solid-liquid mixture are pulverized and refined using an ultrasonic pulverizer, then separated using a centrifuge, and finally dried using a vacuum dryer to obtain a nano-multilayer composite membrane structure Fe / SiO2 material.
[0013] Compared with the prior art, the present invention has the following advantages and effects:
[0014] 1. The process used in this invention to produce Fe / SiO2 nano-multilayer composite film structure is a continuous preparation process;
[0015] 2. The process used in this invention can precisely control the total thickness, number of composite layers, and thickness of each layer of the Fe / SiO2 nano-multilayer composite film structure.
[0016] 3. The Fe / SiO2 nano-multilayer composite film structure prepared by this invention has a good absorption effect on microwaves in the frequency range of 2-18GHz. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of the Fe / SiO2 nanolayered composite film structure.
[0018] Figure 2 This is a flowchart illustrating the preparation process of Fe / SiO2 materials with a nano-multilayer composite film structure. Detailed Implementation
[0020] The present invention will be further described in detail below with reference to embodiments, but the implementation of the present invention is not limited thereto.
[0021] Example 1
[0022] Preparation of alcohol-soluble phenolic resin film: Dilute alcohol-soluble phenolic resin with ethanol or n-butanol to a content of 2% alcohol-soluble phenolic resin; then pass the PET film through the dilute alcohol-soluble phenolic resin solution at a uniform speed, and after drying, a soluble film substrate can be obtained.
[0023] The soluble thin film substrate was placed in a roll-up multi-chamber vacuum deposition apparatus, and the pressure in the deposition chamber was reduced to 10 by evacuation. -2 Pa and maintain stable pressure.
[0024] Soluble thin film substrates are sequentially fed into the No. 1 SiO2 deposition chamber, No. 1 Fe deposition chamber, No. 2 SiO2 deposition chamber, No. 2 Fe deposition chamber and No. 3 SiO2 deposition chamber of a roll-up multi-chamber vacuum deposition equipment at a roll-up speed of 1 m / min.
[0025] The SiO2 deposition chamber uses hexamethyldisiloxane gas, which is generated by heating hexamethyldisiloxane liquid through an 80°C constant temperature water bath. The gas flow rate in the SiO2 deposition chamber is 0.5 L / min. The hexamethyldisiloxane gas is excited by electrons at an excitation voltage of 50 V, and a continuous nano-SiO2 layer is formed by chemical vapor deposition.
[0026] The Fe deposition chamber uses pentacarbonyl iron gas, which is generated by heating pentacarbonyl iron liquid through an 85°C constant temperature water bath. The gas flow rate in the Fe deposition chamber is 0.7 L / min. The pentacarbonyl iron gas is excited by electrons at an excitation voltage of 70 V, and a continuous nano-Fe layer is formed by chemical vapor deposition.
[0027] When starting up the wound multi-chamber vacuum deposition equipment, the gas inlet valve and electronic excitation controller of the first SiO2 deposition chamber are opened, and the subsequent deposition chambers are opened at 2-minute intervals.
[0028] The soluble film with deposited nano-multilayer Fe / SiO2 is passed through the solvent pool in the elution device to basically dissolve the alcohol-soluble phenolic resin, resulting in a solid-liquid mixture containing fragments of the Fe / SiO2 composite film.
[0029] The solid-liquid mixture was then pulverized and refined using an ultrasonic pulverizer, separated using a centrifuge, and finally dried using a vacuum dryer to obtain a nano-multilayer composite film structure Fe / SiO2 material.
[0030] The Fe / SiO2 nanocomposite film structure prepared in this embodiment has the following characteristics: the thickness is basically uniform, with an average total thickness of 3 μm, a total of 5 Fe / SiO2 composite layers, a SiO2 layer thickness of 600 nm, a Fe layer thickness of 600 mm, and good absorption effect for microwaves in the 2-18 GHz frequency range.
[0031] Example 2
[0032] Preparation of alcohol-soluble phenolic resin film: Dilute alcohol-soluble phenolic resin with ethanol or n-butanol to a content of 2% alcohol-soluble phenolic resin; then pass the PET film through the dilute alcohol-soluble phenolic resin solution at a uniform speed, and after drying, a soluble film substrate can be obtained.
[0033] The soluble thin film substrate was placed in a roll-up multi-chamber vacuum deposition apparatus, and the pressure in the deposition chamber was reduced to 10 by evacuation. -2 Pa and maintain stable pressure.
[0034] Soluble thin film substrates are sequentially fed into the No. 1 SiO2 deposition chamber, No. 1 Fe deposition chamber, No. 2 SiO2 deposition chamber, No. 2 Fe deposition chamber, No. 3 SiO2 deposition chamber, No. 3 Fe deposition chamber and No. 4 SiO2 deposition chamber of a roll-up multi-chamber vacuum deposition equipment at a roll-up speed of 2 m / min.
[0035] The SiO2 deposition chamber uses hexamethyldisiloxane gas, which is generated by heating hexamethyldisiloxane liquid through an 80°C constant temperature water bath. The gas flow rate in the SiO2 deposition chamber is 0.5 L / min. The hexamethyldisiloxane gas is excited by electrons at an excitation voltage of 50 V, and a continuous nano-SiO2 layer is formed by chemical vapor deposition.
[0036] The Fe deposition chamber uses pentacarbonyl iron gas, which is generated by heating pentacarbonyl iron liquid through an 85°C constant temperature water bath. The gas flow rate in the Fe deposition chamber is 0.7 L / min. The pentacarbonyl iron gas is excited by electrons at an excitation voltage of 70 V, and a continuous nano-Fe layer is formed by chemical vapor deposition.
[0037] When starting up the wound multi-chamber vacuum deposition equipment, the gas inlet valve and electronic excitation controller of the first SiO2 deposition chamber are opened, and the subsequent deposition chambers are opened at 1-minute intervals.
[0038] The soluble film with deposited nano-multilayer Fe / SiO2 is passed through the solvent pool in the elution device to basically dissolve the alcohol-soluble phenolic resin, resulting in a solid-liquid mixture containing fragments of the Fe / SiO2 composite film.
[0039] The solid-liquid mixture was then pulverized and refined using an ultrasonic pulverizer, separated using a centrifuge, and finally dried using a vacuum dryer to obtain a nano-multilayer composite film structure Fe / SiO2 material.
[0040] The Fe / SiO2 nanocomposite film structure prepared in this embodiment has the following characteristics: the thickness is basically uniform, with an average total thickness of 2.1 μm, a total of 7 Fe / SiO2 composite layers, a SiO2 layer thickness of 300 nm, a Fe layer thickness of 300 mm, and good absorption effect for microwaves in the 2-18 GHz frequency range.
[0041] Example 3
[0042] Preparation of alcohol-soluble phenolic resin film: Dilute alcohol-soluble phenolic resin with ethanol or n-butanol to a content of 2% alcohol-soluble phenolic resin; then pass the PET film through the dilute alcohol-soluble phenolic resin solution at a uniform speed, and after drying, a soluble film substrate can be obtained.
[0043] The soluble thin film substrate was placed in a roll-up multi-chamber vacuum deposition apparatus, and the pressure in the deposition chamber was reduced to 10 by evacuation. -2 Pa and maintain stable pressure.
[0044] Soluble thin film substrates are sequentially fed into the No. 1 SiO2 deposition chamber, No. 1 Fe deposition chamber, No. 2 SiO2 deposition chamber, No. 2 Fe deposition chamber, No. 3 SiO2 deposition chamber, No. 3 Fe deposition chamber and No. 4 SiO2 deposition chamber of a roll-up multi-chamber vacuum deposition equipment, with a film rolling speed of 1 m / min.
[0045] The SiO2 deposition chamber uses hexamethyldisiloxane gas, which is generated by heating hexamethyldisiloxane liquid through an 80°C constant temperature water bath. The gas flow rate in the SiO2 deposition chamber is 0.25 L / min. The hexamethyldisiloxane gas is excited by electrons at an excitation voltage of 50 V, and a continuous nano-SiO2 layer is formed by chemical vapor deposition.
[0046] The Fe deposition chamber uses pentacarbonyl iron gas, which is generated by heating pentacarbonyl iron liquid through an 85°C constant temperature water bath. The gas flow rate in the Fe deposition chamber is 0.7 L / min. The pentacarbonyl iron gas is excited by electrons at an excitation voltage of 70 V, and a continuous nano-Fe layer is formed by chemical vapor deposition.
[0047] When starting up the wound multi-chamber vacuum deposition equipment, the gas inlet valve and electronic excitation controller of the first SiO2 deposition chamber are opened, and the subsequent deposition chambers are opened at 1-minute intervals.
[0048] The soluble film with deposited nano-multilayer Fe / SiO2 is passed through the solvent pool in the elution device to basically dissolve the alcohol-soluble phenolic resin, resulting in a solid-liquid mixture containing fragments of the Fe / SiO2 composite film.
[0049] The solid-liquid mixture was then pulverized and refined using an ultrasonic pulverizer, separated using a centrifuge, and finally dried using a vacuum dryer to obtain a nano-multilayer composite film structure Fe / SiO2 material.
[0050] The Fe / SiO2 nanocomposite film structure prepared in this embodiment has the following characteristics: the thickness is basically uniform, with an average total thickness of 3 μm, a total of 7 Fe / SiO2 composite layers, a SiO2 layer thickness of 300 nm, and a Fe layer thickness of 600 mm. It has a good absorption effect on microwaves in the 2-18 GHz frequency range.
[0051] Example 4
[0052] Preparation of alcohol-soluble phenolic resin film: Dilute alcohol-soluble phenolic resin with ethanol or n-butanol to a content of 2% alcohol-soluble phenolic resin; then pass the PET film through the dilute alcohol-soluble phenolic resin solution at a uniform speed, and after drying, a soluble film substrate can be obtained.
[0053] The soluble thin film substrate was placed in a roll-up multi-chamber vacuum deposition apparatus, and the pressure in the deposition chamber was reduced to 10 by evacuation. -2 Pa and maintain stable pressure.
[0054] Soluble thin film substrates are sequentially fed into the following chambers of a roll-up multi-chamber vacuum deposition apparatus: SiO2 deposition chamber #1, Fe deposition chamber #1, SiO2 deposition chamber #2, Fe deposition chamber #2, SiO2 deposition chamber #3, Fe deposition chamber #3, SiO2 deposition chamber #4, Fe deposition chamber #4, SiO2 deposition chamber #5, Fe deposition chamber #5 and SiO2 deposition chamber #6, with a roll-up speed of 1 m / min.
[0055] The SiO2 deposition chamber uses hexamethyldisiloxane gas, which is generated by heating hexamethyldisiloxane liquid through an 80°C constant temperature water bath. The gas flow rate in the SiO2 deposition chamber is 0.25 L / min. The hexamethyldisiloxane gas is excited by electrons at an excitation voltage of 50 V, and a continuous nano-SiO2 layer is formed by chemical vapor deposition.
[0056] The Fe deposition chamber uses pentacarbonyl iron gas, which is generated by heating pentacarbonyl iron liquid through an 85°C constant temperature water bath. The gas flow rate in the Fe deposition chamber is 0.7 L / min. The pentacarbonyl iron gas is excited by electrons at an excitation voltage of 70 V, and a continuous nano-Fe layer is formed by chemical vapor deposition.
[0057] When starting up the wound multi-chamber vacuum deposition equipment, the gas inlet valve and electronic excitation controller of the first SiO2 deposition chamber are opened, and the subsequent deposition chambers are opened at 1-minute intervals.
[0058] The soluble film with deposited nano-multilayer Fe / SiO2 is passed through a solvent pool in an elution device to basically dissolve the alcohol-soluble phenolic resin, resulting in a solid-liquid mixture containing fragments of the Fe / SiO2 composite film.
[0059] The solid-liquid mixture was then pulverized and refined using an ultrasonic pulverizer, separated using a centrifuge, and finally dried using a vacuum dryer to obtain a nano-multilayer composite film structure Fe / SiO2 material.
[0060] The characteristics obtained in this embodiment are: the thickness is basically uniform, the average total thickness is 4.8 μm, the total number of Fe / SiO2 composite layers is 11, the SiO2 layer thickness is 300 nm, the Fe layer thickness is 600 mm, and it has a good absorption effect on microwaves in the frequency range of 2-18 GHz.
Claims
1. A method for preparing Fe / SiO2 nanoscale multilayer composite membrane structure materials using an organic release membrane method, characterized in that... Includes the following steps: (1) Iron pentacarbonyl and hexamethyldioxane were heated to evaporate and deposited alternately on a soluble thin film substrate under vacuum conditions by chemical vapor deposition to form a nano-multilayer Fe / SiO2 composite film. (2) Dissolve the soluble film substrate with a solvent to peel the nano-multilayer Fe / SiO2 composite film off from the substrate, and obtain a solid-liquid mixture containing Fe / SiO2 composite film fragments; (3) The solid-liquid mixture is subjected to ultrasonic pulverization, centrifugal separation and drying to obtain a nano-multilayer composite film structure Fe / SiO2 material.
2. The method for preparing Fe / SiO2 nano-multilayer composite membrane structure materials by organic release membrane method according to claim 1, characterized in that: In step 1, deposition is carried out alternately on a soluble thin film substrate under vacuum conditions using a roll-up multi-chamber vacuum deposition equipment. The first and last chambers are SiO2 deposition chambers, and Fe deposition chambers are arranged between the SiO2 deposition chambers. The total number of deposition chambers is odd.
3. The method for preparing Fe / SiO2 nano-multilayer composite membrane structure materials by organic release membrane method according to claim 1, characterized in that: In step 1, the soluble film substrate is an alcohol-soluble phenolic resin film.
4. The method for preparing Fe / SiO2 nano-multilayer composite membrane structure materials by organic release membrane method according to claim 1, characterized in that: In step 1, the total number of layers in the nano-multilayer Fe / SiO2 composite film is odd, with the surface and bottom layers being SiO2 layers and Fe layers interspersed between each SiO2 layer.
5. The method for preparing Fe / SiO2 nano-multilayer composite membrane structure materials by organic release membrane method according to claim 1, characterized in that: In step 2, the solvent is ethanol or n-butanol.
6. The method for preparing Fe / SiO2 nano-multilayer composite membrane structure materials by organic release membrane method according to claim 1, characterized in that: In step 3, the solid-liquid mixture is filtered, ultrasonically pulverized, centrifuged, and dried. This includes first using an ultrasonic pulverizer to pulverize and refine the Fe / SiO2 composite membrane fragments in the solid-liquid mixture, then using a centrifuge to separate them, and finally using a vacuum dryer to dry them to obtain a nano-multilayer composite membrane structure Fe / SiO2 material.