Unlock instant, AI-driven research and patent intelligence for your innovation.

A microwave absorbing material with adjustable absorption frequency and its preparation method

A microwave-absorbing material and frequency-absorbing technology, which is applied in electrical components, antennas, magnetic field/electric field shielding, etc., can solve the problems of reducing microwave-absorbing performance and inability to effectively form a conductive network, and achieve adjustable microwave-absorbing frequency and good microwave absorption Excellent performance and performance

Active Publication Date: 2018-01-12
FUDAN UNIV
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[7] Reaching the permeation threshold of carbon nanotubes in polymer matrices is crucial for the preparation of high-performance microwave absorbers [8] , but due to the large aspect ratio and specific surface area of ​​carbon nanotubes, it is very easy to agglomerate and entangle in the polymer matrix, so that the conductive network cannot be effectively formed, thus greatly reducing its absorbing performance

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A microwave absorbing material with adjustable absorption frequency and its preparation method
  • A microwave absorbing material with adjustable absorption frequency and its preparation method
  • A microwave absorbing material with adjustable absorption frequency and its preparation method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0026] First, the preparation of aligned carbon nanotube films

[0027] Fe (thickness 1~2nm) / Al 2 o 3 (thickness of 10±2 nm) is the catalyst, ethylene is the carbon source, and the mixed gas of argon and hydrogen is the gas phase carrier, among which, Al 2 o 3 As a buffer layer, Fe is used as a catalyst, and a nanometer-thick film is deposited on a silicon wafer by an electron beam evaporation coating device; chemical vapor deposition is used, ethylene is used as a carbon source, and argon and hydrogen are used as a carrier gas. Synthesize vertically grown carbon nanotube arrays on Si substrates; the ethylene flow rate is 180-300 sccm, the argon flow rate is 390-650 sccm, and the hydrogen flow rate is 20-50 sccm, grown in a tube furnace for 10-180 min, namely A vertically grown carbon nanotube array is obtained. The details of synthesis and self-assembly can refer to existing literature reports. Use a polytetrafluoroethylene roller with a smooth surface to roll the carbo...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
thicknessaaaaaaaaaa
thicknessaaaaaaaaaa
thicknessaaaaaaaaaa
Login to View More

Abstract

The invention belongs to the technical field of preparation of microwave absorbing materials, in particular to a microwave absorbing material with adjustable absorption frequency and a preparation method. The single-layer oriented carbon nanotube film of the microwave absorbing material of the present invention is composed of highly oriented carbon nanotubes arranged in the same direction, and the surface density is about 1.97 g m-2. By changing the angle between the two layers of aligned carbon nanotube films (0-90 degrees), a series of microwave absorbing materials with adjustable absorption frequency can be obtained; through electron beam evaporation and electrochemical polymerization, composite iron and polyaniline to further improve the microwave absorption properties of the material. The invention realizes the control of the wave-absorbing frequency by adjusting the included angle of two layers of oriented carbon nanotube films; and improves the microwave absorption performance by increasing the number of layers of oriented carbon nanotube films or compounding with iron and polyaniline.

Description

technical field [0001] The invention belongs to the technical field of preparation of microwave absorbing materials, and in particular relates to a microwave absorbing material with adjustable absorption frequency and a preparation method thereof. Background technique [0002] For a long time, adjusting the absorption frequency has been a crucial but challenging problem in the field of microwave absorption. [1-3] In precision electronic instruments, when the frequency of external electromagnetic waves changes, the absorbing material needs to adjust the absorbing frequency accordingly to protect the stable operation of the internal instrument; in the military field, electromagnetic waves of different frequencies are often used for reconnaissance targets, which also requires absorbing materials Can effectively control the absorption frequency. Although researchers have conducted extensive and in-depth research on adjusting the absorbing frequency, changing the thickness of th...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): H05K9/00H01Q17/00
Inventor 彭慧胜车仁超孙浩
Owner FUDAN UNIV
Features
  • R&D
  • Intellectual Property
  • Life Sciences
  • Materials
  • Tech Scout
Why Patsnap Eureka
  • Unparalleled Data Quality
  • Higher Quality Content
  • 60% Fewer Hallucinations
Social media
Patsnap Eureka Blog
Learn More

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2025 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com