Composite wave-absorbing material and preparation method thereof

A technology of composite wave-absorbing material and wave-absorbing layer, which is applied in the field of wave-absorbing materials, can solve the problem that wave-absorbing materials cannot have a wide frequency band at the same time, and achieve the effect of good compatibility and good elongation and stretching performance

Pending Publication Date: 2021-01-12
SHENZHEN GRADUATE SCHOOL TSINGHUA UNIV
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At present, most of the absorbing materials on the market adopt a single layered structure, which can only satisfy one of wave impedance matching or high loss performance. Therefore, the produced absorbing materials cannot have the characteristics of wide frequency band and strong absorption at the same time.

Method used

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  • Composite wave-absorbing material and preparation method thereof
  • Composite wave-absorbing material and preparation method thereof
  • Composite wave-absorbing material and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] The absorbing agent used in this example is hydroxyl iron powder and hollow glass microspheres. The curing temperature of epoxy resin a is 130-180°C, and the viscosity at 50°C is 4500-5800mPa·s. The curing temperature of epoxy resin b is The viscosity at 170-200°C and 50°C is 35000-42000mPa·s. The structure diagram of the prepared composite absorbing material is as follows figure 1 As shown, 100 is hydroxyl iron powder, 200 is hollow glass microspheres, and 300 is epoxy resin layer. The preparation process refers to figure 2 , specifically prepared according to the following steps:

[0036] 5 grams of hydroxyl iron powder, 3 grams of hollow glass microspheres, 100 grams of epoxy resin a, and 16 milliliters of organic solvent (by mixing ethyl acetate and N,N-dimethylformamide at 1:1) were added to the In the tank body of the planetary ball mill, ball mill for 3 hours at a speed of 350r / min, and the filtered slurry is sealed for subsequent use. The above slurry is deno...

Embodiment 2

[0047] The absorbing agent used in this example is iron nitride and activated carbon fiber, the mass ratio of iron nitride and activated carbon fiber is 10:1, the curing temperature of epoxy resin a is 130-180°C, and the viscosity at 50°C is 2000- 8000mPa·s, the curing temperature of epoxy resin b is 170-200°C, and the viscosity at 50°C is 20000-70000mPa·s. It is prepared according to the preparation steps of Example 1, and the proportions of wave-absorbing agents in different wave-absorbing layers are respectively 10%, 25%, 40%, 55%, 70%, 85%, the thickness of a single double-layer raw tape is 150 μm, and the thickness of the multilayer composite absorbing material obtained after lamination and curing is about 700 μm, and It can be flexibly adjusted according to actual needs.

Embodiment 3

[0049] The wave absorbing agent used in this example is sendust powder and carbon nanotubes, the ratio of sendust powder to carbon nanotubes is 15:1, the curing temperature of epoxy resin a is 130-180°C, and the viscosity is 50°C is 2000-8000mPa·s, the curing temperature of epoxy resin b is 170-200°C, and the viscosity at 50°C is 20000-70000mPa·s. It is prepared according to the preparation steps of Example 1, wherein the proportions of wave-absorbing agents in different wave-absorbing layers The ratios are 5%, 20%, 35%, 50%, 65%, and 80%, respectively. The thickness of a single double-layer raw tape is 150 μm, and the thickness of the multilayer composite absorbing material obtained after lamination and curing is about 1100μm, and can be flexibly adjusted according to actual needs.

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Abstract

The invention discloses a composite wave-absorbing material and a preparation method thereof.The composite wave-absorbing material comprises a plurality of wave-absorbing layers, the wave-absorbing layers comprise a wave-absorbing agent and first epoxy resin, the curing temperature of the first epoxy resin is 130-180 DEG C, and the viscosity of the first epoxy resin at 50 DEG C is 2000-8000 mPa.s,the epoxy resin layers are arranged among the plurality of wave absorbing layers, each epoxy resin layer comprises second epoxy resin and a curing agent, the curing temperature of the second epoxy resin is 170-200 DEG C, and the viscosity of the second epoxy resin at 50 DEG C is 20000-70000mPa. S. The first epoxy resin has good compatibility with the wave-absorbing agent particles, the second epoxy resin has better extension and tensile properties, and the addition of the curing agent can improve the crosslinking degree of the second epoxy resin after curing, so that the bonding between the wave-absorbing layers is stable, and meanwhile, the problem that a single layered structure cannot meet wave impedance matching and high loss performance at the same time is avoided.

Description

technical field [0001] The invention relates to the technical field of wave-absorbing materials, in particular to a composite wave-absorbing material and a preparation method thereof. Background technique [0002] With the rapid development of the electronics industry, communication systems, scientific and medical equipment, etc. have produced serious electromagnetic wave pollution, which has caused great interference to the operation of high-precision instruments. Therefore, it is necessary to equip an efficient wave-absorbing material. In the military field, wave-absorbing materials can absorb electromagnetic waves emitted by enemy radars, reduce the probability of one's own military units such as aircraft and missiles being detected by reconnaissance, and improve strategic deterrence. To a certain extent, it can determine the outcome of a war. [0003] The absorption efficiency of electromagnetic wave absorbing materials depends on the incidence and loss of electromagnet...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): B32B27/38B32B27/18B32B27/06B32B33/00C08L63/00C08K3/18C08K7/28C08K3/28C08K7/06C08K3/34C08K3/04H05K9/00
CPCB32B27/38B32B27/18B32B27/08B32B33/00C08K3/18C08K7/28C08K3/28C08K7/06C08K3/34C08K3/041H05K9/0081C08K2201/011B32B2307/212C08L63/00
Inventor 李勃陈劲张晗朱朋飞王荣
Owner SHENZHEN GRADUATE SCHOOL TSINGHUA UNIV
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