CN101080163A - Electromagnetic foam absorption wedge material and its making technology - Google Patents
Electromagnetic foam absorption wedge material and its making technology Download PDFInfo
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- CN101080163A CN101080163A CN 200710015954 CN200710015954A CN101080163A CN 101080163 A CN101080163 A CN 101080163A CN 200710015954 CN200710015954 CN 200710015954 CN 200710015954 A CN200710015954 A CN 200710015954A CN 101080163 A CN101080163 A CN 101080163A
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Abstract
This invention relates to a high fire-retarding electromagnetic wave absorption foam edgetone material including rigid phenolic foam and a wave absorbent, in which, the rigid phenolic foam is taken as the carrier to prepare wedge and the wave absorbent is scattered in the wedge. The preparation method includes: a, preparing resol as the basic material, b, taking the expandable phenolic resin prepared by the resol, a emulsifying agent, vesicant and wave absorbent as component A and a solidifying agent of the resin mixed by inorganic acid and organic acid as component B, c, pouring component A and B together into a wedge model cavity, d, controlling the temperature of the cavity at 50-70deg.C to be foamed and molded and the foam is aged for 60-90min in the cavity.
Description
Technical field
The present invention relates to be applied to set up the shielded anechoic chamber that is not subjected to Electromagnetic Interference, form free space dead zone wideband absorbing material, relate in particular to a kind of electromagnetic foam absorption wedge material and preparation technology thereof.
Background technology
Along with national defense industry and rapid development of national economy, going from bad to worse of China's electromagnetic wave environment more and more causes the attention of the parties concerned.In order to prevent that periphery electromagnetic environment from producing harmful effect to the electromagnetic measurement of precision electronic element, instrument, equipment, needs to set up the shielded anechoic chamber that is not subjected to Electromagnetic Interference; For electromagnetic environment true to nature being provided for antenna measurement, the test of electronic countermeasures analogue simulation, also need to build shielding and inhale the ripple darkroom, to form the free space dead zone.
All will build some shieldings domestic every year and inhale the ripple darkroom, at six faces or five faces of inhaling the ripple darkroom, all the electromagnetic wave foam absorption wedge will be installed, inhaling the ripple wedge is to build the material of inhaling ripple darkroom most critical.At present, it is that charcoal technology or coating-type foamed material are oozed in the carrier employing mostly with the flexible polyurethane foams that this class is inhaled the production of ripple wedge, and its properties of product can not satisfy the instructions for use of shielded anechoic chamber fully, and major defect has: 1) wave absorbing agent skewness; 2) falling powdered carbon in the use easily causes absorbing property to descend; 3) useful life shorter, wedge is easily sagging even usually come off in the use; 4) need bonding construction, construction is difficulty comparatively; 5) fire resistance is relatively poor, breaking out of fire easily; 6) cost an arm and a leg
Summary of the invention
The electromagnetic foam absorption wedge material and the preparation technology thereof that the purpose of this invention is to provide a kind of high flame retardant.
For achieving the above object, the technical solution used in the present invention is: a kind of electromagnetic foam absorption wedge material, and its characteristics are: comprising hard phenol formaldehyde foam, wave absorbing agent; With the hard phenol formaldehyde foam is that carrier is made wedge, and wave absorbing agent is dispersed in the wedge; The wedge brushing becomes white; Its preparation technology is as follows:
A, preparation resol are as basic raw material;
B, the expandable phenolic resin that is made into resol, emulsifying agent, blowing agent, wave absorbing agent are the A component, and it is the B component that inorganic acid and organic acid mix the curing agent that is made into expandable phenolic resin;
C, A component and the mixing of B component are poured in the wedge mould die cavity;
D, die cavity temperature are controlled at 50～70 ℃ of foamings; Foam slaking 60～90 minutes in die cavity.
Advantageous effect of the present invention is: because the present invention is comprising hard phenol formaldehyde foam, wave absorbing agent; With the hard phenol formaldehyde foam is that carrier is made wedge, and wave absorbing agent is dispersed in the wedge; Electromagnetic foam absorption wedge material preparation technology mixes wave absorbing agent and phenolic resins earlier, injects to foam in the mould by reaction injection molding machine then and makes.Advantage such as this product has that intensity height, wave absorbing agent are evenly distributed, not not sagging, the easy construction of dry linting, wedge, fire resistance are good.By its absorbing property, fire resistance, anti-compression properties and high and low temperature resistance are tested, can satisfy the instructions for use of microwave dark room fully.While is owing to phenol formaldehyde foam is lower with respect to the polyurethane foam cost, so cost of the present invention is low.
Electromagnetic foam absorption wedge adopts mould molding, can make many cones (being generally four awls).Break through tradition and made the production technology of singly boring again brush coating bonding component units piece earlier.
It is carrier that electromagnetic foam absorption wedge material adopts high flame retardant foam phenol formaldehyde foam, and phenol formaldehyde foam has oxygen index height, characteristic that smoke density is low, has thoroughly solved the hidden danger that the darkroom catches fire.
Use foam to inhale the ripple wedge and enter when propagating in the material when electromagnetic wave exactly, make electromagnetic wave energy be converted into heat energy and produce loss.The main loss material of foam absorption wedge is the conductive powder of carbon black, graphite one class.Because the shape of foam wedge makes the performance gradual change of material, from boring point, incident wave is formed the impedance conversion that gradually changes to the awl end, make it have good attenuation by absorption.The surperficial input impedance of foam wedge can be represented by the formula
In the formula:
The Zs-impedance
Yo-free space admittance value
H-wedge height
Z-wedge summit is to the point of observation distance
The electric conductivity value of G-absorbing material
On the wedge summit, Zs is the free space wave impedance, and impedance is along with the height of wedge increases and reduces when ripple is propagated in wedge.Irradiation of electromagnetic waves be can change and spillage of material, phase cancellation and diffusion distributed.
What the said high flame retardant of the present invention was exactly a phenol formaldehyde foam itself is exactly fire proofing.
Electromagnetic foam absorption wedge material adopts mould one-shot forming, 1) wave absorbing agent is evenly distributed; 2) not falling powdered carbon in the use causes absorbing property good; 3) useful life longer, wedge is not sagging in the use; 4) once can produce a cell block by mould.Solve single awl brush coating and be bonded to cell block, improved production efficiency.
The electromagnetic foam absorption wedge material carrier is that phenol formaldehyde foam is a kind of rigid foam, has the intensity height, can adopt machinery to install when mounted.The advantage that machinery is installed is with respect to bonding installation, inhale the ripple wedge and adopt machinery that following advantage: a is installed to install firmly, useful life the head; The b quick construction is convenient, and the construction site does not have residue, has no irritating odor; C darkroom no pernicious gas in long-term use is emitted; D inhales the ripple wedge and changes conveniently.
It is carrier that electromagnetic foam absorption wedge material adopts phenol formaldehyde foam, and phenol formaldehyde foam has natural flame retardancy, has solved the disaster hidden-trouble in darkroom completely.
Description of drawings
Fig. 1 is a structural representation of the present invention.
Embodiment
Further specify embodiments of the present invention and effect with following indefiniteness embodiment:
As shown in Figure 1, under the condition of material behavior unanimity, the effect of suction ripple is along with the height of wedge 1 increases and increases, and it highly is the electromagnetic foam absorption wedge material of 500mm (H500 type), 700mm (H700 type), three kinds of models of 1000mm (H1000 type) that the present invention has prepared.A kind of electromagnetic foam absorption wedge material is comprising hard phenol formaldehyde foam, wave absorbing agent; With the hard phenol formaldehyde foam is that carrier is made wedge 1, and wave absorbing agent is dispersed in the wedge 1, and the wedge bottom has base 2, and base 2 is an integral body with wedge 1; Wave absorbing agent is dispersed in the wedge 1 uniformly, and the wave absorbing agent quality accounts for 3～10% of wedge 1 quality.
A kind of preparation technology of electromagnetic foam absorption wedge material is as follows:
A, preparation resol are as basic raw material.
B, the expandable phenolic resin that is made into resol, emulsifying agent, blowing agent, wave absorbing agent are the A component, and it is the B component that inorganic acid and organic acid mix the curing agent that is made into expandable phenolic resin.
C, A component and the mixing of B component are poured in the wedge mould die cavity.
D, die cavity temperature are controlled at 50～70 ℃ of foamings; Foam slaking 60～90 minutes in die cavity.
The prescription of expandable phenolic resin proportioning by weight is a resol: emulsifying agent: blowing agent: wave absorbing agent=100: 2～5: 5～10: 3～10; The prescription of the expandable phenolic resin best proportioning of proportioning by weight is a resol: emulsifying agent: blowing agent: wave absorbing agent=100: 3: 6: 8; The prescription of curing agent proportioning by weight is a water: p-methyl benzenesulfonic acid: sulfuric acid=1: 1: 1; A component and B component proportioning by weight are A: B=100: 10～20; It is in 50～70 ℃ the drying room that die cavity is placed on temperature; The wedge brushing becomes white.
Concrete enforcement is as follows:
Embodiment 1:
Among the preparation technology of above-mentioned H500 type electromagnetic foam absorption wedge material:
(1) proportioning by weight
The preparation of A component: 100 parts of resols, emulsifying agent 2～5 parts of (silicone oil hard bubbles), blowing agent 5～10 parts of (pentane), wave absorbing agents stir under high-speed stirring apparatus for 5～10 parts and are mixed with expandable phenolic resin half an hour.
The preparation of B component: water: p-methyl benzenesulfonic acid: sulfuric acid=1: 1: 1
(2) H500 type wedge mould is placed in 50～70 ℃ the drying room, makes the temperature of mould reach 50～70 ℃.
(3) according to expandable phenolic resin: the ratio of curing agent=100: 15 is expelled in the wedge die cavity by reaction injection molding machine.
(4) foam slaking moulding in 60～90 minutes in die cavity.
(5) carry out after the wedge demoulding brushing white environmental protection coating material after the simple surface treatment.
In the present embodiment, what emulsifying agent used is the silicone oil that hard bubbles, and what blowing agent used is pentane, and what wave absorbing agent used is the conductive powder of carbon black, graphite one class.
In the present embodiment, best by weight proportioning:
The preparation of A component: 100 parts of resols, emulsifying agent 2 parts of (silicone oil hard bubbles), blowing agent 5 parts of (pentane), wave absorbing agents stir under high-speed stirring apparatus for 5 parts and are mixed with expandable phenolic resin half an hour.
Embodiment 2:
Among the preparation technology of aforementioned H700 type electromagnetic foam absorption wedge material:
(1) proportioning by weight:
The preparation of A component: 100 parts of resols, 2～5 parts of emulsifying agents, 5～10 parts of blowing agents, wave absorbing agent stir under high-speed stirring apparatus for 5～10 parts and are mixed with expandable phenolic resin half an hour.
In the present embodiment, best by weight proportioning:
The preparation of A component: 100 parts of resols, 3 parts of emulsifying agents, 8 parts of blowing agents, wave absorbing agent stir under high-speed stirring apparatus for 7 parts and are mixed with expandable phenolic resin half an hour.
The preparation of B component: water: p-methyl benzenesulfonic acid: sulfuric acid=1: 1: 1.
(2) H700 type wedge mould is placed in 50～70 ℃ the drying room, makes the temperature of mould reach 50～70 ℃.
(3) according to expandable phenolic resin: the ratio of curing agent=100: 15 is expelled in the wedge die cavity by reaction injection molding machine.
(4) foam slaking moulding in 60～90 minutes in die cavity.
(5) carry out after the wedge demoulding brushing white environmental protection coating material after the simple surface treatment.
In the present embodiment, what emulsifying agent used is the silicone oil that hard bubbles, and what blowing agent used is pentane, and what wave absorbing agent used is the conductive powder of carbon black, graphite one class.
Embodiment 3:
Among the preparation technology of aforementioned H1000 type electromagnetic foam absorption wedge material:
(1) proportioning by weight
The preparation of A component: 100 parts of resols, 2～5 parts of emulsifying agents, 5～10 parts of blowing agents, wave absorbing agent stir under high-speed stirring apparatus for 5～10 parts and are mixed with expandable phenolic resin half an hour.
The preparation of B component: water: p-methyl benzenesulfonic acid: sulfuric acid=1: 1: 1.
(2) H1000 type wedge mould is placed in 50～70 ℃ the drying room, makes the temperature of mould reach 50～70 ℃.
(3) according to expandable phenolic resin: the ratio of curing agent=100: 15 is expelled in the wedge die cavity by reaction injection molding machine.
(4) foam slaking moulding in 60～90 minutes in die cavity.
(5) carry out after the wedge demoulding brushing white environmental protection coating material after the simple surface treatment.
In the present embodiment, what emulsifying agent used is the silicone oil that hard bubbles, and what blowing agent used is pentane, and what wave absorbing agent used is the conductive powder of carbon black, graphite one class.
In the present embodiment, best by weight proportioning:
The preparation of A component: 100 parts of resols, 5 parts of emulsifying agents, 10 parts of blowing agents, wave absorbing agent stir under high-speed stirring apparatus for 10 parts and are mixed with expandable phenolic resin half an hour.
The electromagnetic foam absorption wedge material that the present invention makes is absorbing property such as table 1 after tested
Table 1, the test of electromagnetic foam absorption wedge material absorbing property
| Frequency/GHz | Absorbing property/dB | ||
| H-500 | H-700 | H-1000 | |
| 0.7 | 24 | 23.6 | 26 |
| 1.0 | 25 | 26 | 29.3 |
| 1.3 | 25.6 | 27 | 31.7 |
| 1.5 | 27 | 33 | 33 |
| 2.0 | 28 | 34 | 35 |
| 3.0 | 32 | 34 | 36 |
| 4.0 | 33 | 35 | 38 |
| 5.0 | 33 | 38 | 40 |
| 6.0 | 33 | 38 | 42 |
| 7.0 | 34 | 40 | 45 |
| 8.0 | 34 | 40 | 46 |
| 9.0 | 34 | 40 | 47 |
| 10.0 | 35 | 41 | 48 |
| 11.0 | 36 | 41 | 48 |
| 12.0 | 38 | 42 | 50. |
| 13.0 | 40 | 43 | 50 |
| 14.0 | 42 | 44 | 50 |
| 15.0 | 44 | 45 | 50 |
| 16.0 | 48 | 48 | 50 |
| 17.0 | 50 | 50 | 52 |
| 18.0 | 50 | 50 | 55 |
The electromagnetic foam absorption wedge material that the present invention makes is physical property such as table 2 after tested.
Table 2, the test of electromagnetic foam absorption wedge material absorbing property
| Project | Technical indicator |
| Density | 55kg/m 3 |
| Compressive strength | 270kpa |
| Oxygen index | 42 |
Claims (10)
1, a kind of electromagnetic foam absorption wedge material is characterized in that: comprising hard phenol formaldehyde foam, wave absorbing agent; With the hard phenol formaldehyde foam is that carrier is made wedge (1), and wave absorbing agent is dispersed in the wedge (1).
2, electromagnetic foam absorption wedge material according to claim 1 is characterized in that: described wedge bottom has base (2), and base (2) is an integral body with wedge (1).
3, electromagnetic foam absorption wedge material according to claim 1 and 2 is characterized in that: described wave absorbing agent is dispersed in the wedge (1) uniformly, and the wave absorbing agent quality accounts for 3～10% of wedge (1) quality.
4, a kind of preparation technology of electromagnetic foam absorption wedge material as claimed in claim 1 is characterized in that: its preparation technology is as follows:
A, preparation resol are as basic raw material;
B, the expandable phenolic resin that is made into resol, emulsifying agent, blowing agent, wave absorbing agent are the A component, and it is the B component that inorganic acid and organic acid mix the curing agent that is made into expandable phenolic resin;
C, A component and the mixing of B component are poured in the wedge mould die cavity;
D, die cavity temperature are controlled at 50～70 ℃ of foamings; Foam slaking 60～90 minutes in die cavity.
5, the preparation technology of electromagnetic foam absorption wedge material according to claim 4, the prescription that it is characterized in that described b stage expandable phenolic resin proportioning by weight is a resol: emulsifying agent: blowing agent: wave absorbing agent=100: 2～5: 5～10: 3～10.
6, according to the preparation technology of claim 4 or 5 described electromagnetic foam absorption wedge materials, the prescription that the it is characterized in that described expandable phenolic resin best proportioning of proportioning by weight is a resol: emulsifying agent: blowing agent: wave absorbing agent=100: 3: 6: 8.
7, the preparation technology of electromagnetic foam absorption wedge material according to claim 6, the prescription that it is characterized in that the agent of described b stage solidification proportioning by weight is a water: p-methyl benzenesulfonic acid: sulfuric acid=1: 1: 1.
8, the preparation technology of electromagnetic foam absorption wedge material according to claim 7 is characterized in that the described c stage, and A component and B component proportioning by weight are A: B=100: 10～20.
9, the preparation technology of electromagnetic foam absorption wedge material according to claim 8 is characterized in that it is in 50～70 ℃ the drying room that described d stage die cavity is placed on temperature.
10, the preparation technology of electromagnetic foam absorption wedge material according to claim 9, it is characterized in that described wedge (1) brush white.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200710015954 CN101080163A (en) | 2007-06-11 | 2007-06-11 | Electromagnetic foam absorption wedge material and its making technology |
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|---|---|---|---|
| CN 200710015954 CN101080163A (en) | 2007-06-11 | 2007-06-11 | Electromagnetic foam absorption wedge material and its making technology |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101769058A (en) * | 2010-02-12 | 2010-07-07 | 泰州拓谷超细粉体材料有限公司 | Multilayer microwave unreflected chamber absorbing material filled by loose foam blocks |
| CN102320090A (en) * | 2011-09-26 | 2012-01-18 | 国营红阳机械厂 | The dull and stereotyped preparation method of a kind of phenolic resins pour mass |
| CN104445934A (en) * | 2014-11-11 | 2015-03-25 | 中国人民解放军国防科学技术大学 | High-temperature-resistant wedge-shaped microwave absorbing material and preparation method thereof |
| CN105356067A (en) * | 2015-11-26 | 2016-02-24 | 深圳唯创微波技术有限公司 | Wave-absorbing structure |
| CN106558262A (en) * | 2015-09-24 | 2017-04-05 | 北京卫星环境工程研究所 | Suction wave apparatus with high temperature-low temperature analog capability |
| CN107286594A (en) * | 2016-03-31 | 2017-10-24 | 深圳光启高等理工研究院 | Absorbing material and preparation method thereof |
| CN113956606A (en) * | 2021-10-21 | 2022-01-21 | 中国电子科技集团公司第三十三研究所 | Carbon nano composite wave-absorbing heat-insulating phenolic foam material and preparation method thereof |
| CN115103587A (en) * | 2022-08-05 | 2022-09-23 | 南京航空航天大学 | Flame-retardant wave-absorbing material and preparation method thereof |
| CN117430919A (en) * | 2023-11-28 | 2024-01-23 | 珠海鲁班智造科技有限公司 | High-power wedge wave-absorbing material and preparation method thereof |
-
2007
- 2007-06-11 CN CN 200710015954 patent/CN101080163A/en active Pending
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101769058A (en) * | 2010-02-12 | 2010-07-07 | 泰州拓谷超细粉体材料有限公司 | Multilayer microwave unreflected chamber absorbing material filled by loose foam blocks |
| CN102320090A (en) * | 2011-09-26 | 2012-01-18 | 国营红阳机械厂 | The dull and stereotyped preparation method of a kind of phenolic resins pour mass |
| CN102320090B (en) * | 2011-09-26 | 2013-06-05 | 国营红阳机械厂 | Phenolic resin casting plate preparation method |
| CN104445934A (en) * | 2014-11-11 | 2015-03-25 | 中国人民解放军国防科学技术大学 | High-temperature-resistant wedge-shaped microwave absorbing material and preparation method thereof |
| CN106558262A (en) * | 2015-09-24 | 2017-04-05 | 北京卫星环境工程研究所 | Suction wave apparatus with high temperature-low temperature analog capability |
| CN105356067A (en) * | 2015-11-26 | 2016-02-24 | 深圳唯创微波技术有限公司 | Wave-absorbing structure |
| CN107286594A (en) * | 2016-03-31 | 2017-10-24 | 深圳光启高等理工研究院 | Absorbing material and preparation method thereof |
| CN113956606A (en) * | 2021-10-21 | 2022-01-21 | 中国电子科技集团公司第三十三研究所 | Carbon nano composite wave-absorbing heat-insulating phenolic foam material and preparation method thereof |
| CN115103587A (en) * | 2022-08-05 | 2022-09-23 | 南京航空航天大学 | Flame-retardant wave-absorbing material and preparation method thereof |
| CN117430919A (en) * | 2023-11-28 | 2024-01-23 | 珠海鲁班智造科技有限公司 | High-power wedge wave-absorbing material and preparation method thereof |
| CN117430919B (en) * | 2023-11-28 | 2024-05-24 | 珠海鲁班智造科技有限公司 | High-power wedge wave-absorbing material and preparation method thereof |
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Open date: 20071128 |