Low-frequency stage microwave absorption material

A microwave absorbing material, low-frequency microwave technology, applied in other chemical processes, chemical instruments and methods, etc., can solve problems such as insufficient microwave absorption performance, and achieve the effect of meeting the needs of materials

Inactive Publication Date: 2013-12-11
NANJING BOPING ELECTRONICS TECH CO LTD
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] In order to solve the insufficient microwave absorption performance of the existing polyurethane pyramidal microwave absorbing materials at low frequencies of 30-100MHz, the present invention provides a microwave absorbing material for low-frequency bands and its manufacturing method, which realizes microwave absorption of 12-20dB for 30MHz-100MHz, and 12-20dB for other frequency bands. The microwave absorption performance is consistent with that of conventional polyurethane pyramid absorbing materials

Method used

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Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0023] Weigh 710g of water and 11g of dispersant N into a plastic container, set the speed at 500RPM, and disperse evenly with an F-0.4 high-speed disperser. Then add 32g of conductive carbon black, 15g of magnesium titanate, 11g of silicon dioxide, 15g of tetrabromobisphenol A, and 5g of antimony trioxide in sequence, adjust the rotation speed to 1500RPM, and disperse for 20min to form a conductive paste. Import the conductive paste into the LKS-21 vertical sand mill, and the sanding time is 30min. After sanding, the conductive slurry is filtered with a 300-mesh stainless steel gauze, and 200g of S-07 acrylic binder (solid content 35%) and 1g of 090 defoamer are added, and dispersed in F-0.4 dispersing equipment for 25 minutes to make water-based Microwave absorbs the solution. Impregnate polyurethane foam, dry at 80°C for 24h, the measured equivalent square resistance is 400-420Ω, according to figure 1 Form the pyramid 1.

[0024] Weigh 702g of water and 11g of dispersant...

Embodiment 2

[0027] Weigh 710g of water and 11g of dispersant N into a plastic container, set the speed at 500RPM, and disperse evenly with an F-0.4 high-speed disperser. Then add 24g of conductive carbon black, 8g of conductive graphite, 15g of strontium titanate, 11g of silicon dioxide, 15g of tetrabromobisphenol A, 5g of antimony trioxide, adjust the rotation speed to 1500RPM, and disperse for 20min to form a conductive paste. Import the conductive paste into the LKS-21 vertical sand mill, and the sanding time is 30min. After sanding, the conductive paste is filtered with 300-mesh stainless steel gauze, and 200g of S-07 acrylic binder (solid content 35%) and 1g of 090 defoamer are added, and dispersed in F-0.4 high-speed disperser for 25 minutes to make water-based Microwave absorbs the solution. Impregnate polyurethane foam plastics and dry at 80°C for 24 hours. The measured equivalent square resistance is 520-560Ω, according to figure 1 Form the pyramid 1.

[0028] Weigh 702g of wa...

Embodiment 3

[0031] Weigh 714g of water and 11g of dispersant N into a plastic container, set the speed at 500RPM, and disperse evenly with an F-0.4 high-speed disperser. Then add 28g of conductive carbon black, 15g of magnesium carbonate, 11g of silicon dioxide, 15g of tetrabromobisphenol A, and 5g of antimony trioxide in sequence, adjust the rotation speed to 1500RPM, and disperse for 20min to form a conductive paste. Import the conductive paste into the LKS-21 vertical sand mill, and the sanding time is 30min. After sanding, the conductive slurry is filtered with a 300-mesh stainless steel gauze, and 200g of S-07 acrylic binder (solid content 35%) and 1g of 090 defoamer are added, and dispersed in an F-0.4 high-speed disperser for 25 minutes to make a water-based microwave oven. Absorb the solution. Immerse polyurethane foam plastics and dry at 80°C for 24 hours. The measured equivalent square resistance is 480-510Ω, according to figure 1 Form the pyramid 1.

[0032] Weigh 695g of wa...

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Abstract

The invention relates to a low-frequency stage microwave absorption material which comprises a polyurethane pyramid and a base, wherein the polyurethane pyramid is internally provided with two same inner single cones close to the base; three-layer microwave absorption sheets with same square resistance values are arranged above the inner single cones and parallel to a cone base; the square resistance values of the microwave absorption sheets range from 350 ohm to 420 ohm, the square resistance of the polyurethane pyramid ranges from 400 ohm to 600 ohm, and the square resistances of the inner single cones range from 150 ohm to 200 ohm. According to the invention, the three-layer parallel structure approximate to an electric wave in space equivalent square resistance value (377 ohm) is arranged in a polyurethane pyramid material, so that the microwave absorption property of the polyurethane pyramid wave-absorbing material between 30 MHz and 100 MHz is improved, and the absorption value ranges from -12 dB to 20 dB. The low-frequency stage microwave absorption material disclosed by the invention meets the requirement for electromagnetic compatibility and the requirement of an antenna simulation darkroom on the material.

Description

technical field [0001] The invention relates to a low-frequency microwave absorbing material and a preparation method thereof, which are mainly used for improving the absorption performance of the polyurethane pyramidal absorbing material in the frequency range of 30MHz to 100MHz. Background technique [0002] Polyurethane pyramid absorbing material is made of conductive carbon black, flame retardant and other raw materials. Through multiple extrusion of polyurethane foam in the impregnating machine, the amount of liquid absorbed by the foam is controlled, dried at high temperature, and cut into regular four-sided pyramid-shaped microwave absorbing materials. Material. Its shape and structure make the vertically incident space electromagnetic wave have a radio impedance matching effect at the cone tip of the pyramid absorbing material, so that the electromagnetic wave can enter the interior of the polyurethane pyramid absorbing material to the maximum extent, and its interna...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): C09K3/00C08J9/40C08J9/42
Inventor 胡益民
Owner NANJING BOPING ELECTRONICS TECH CO LTD
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