TW201006872A - Electromagnetic wave absorber containing ferric powder and preparation method thereof - Google Patents

Abstract

The invention relates to an electromagnetic wave absorber containing ferric powder and its preparation method. The electromagnetic wave absorber containing ferric powder comprises 40-70 percents by weight of resin; and 30-60 percents by weight of ferric powder, wherein the apparent density of the ferric powder is 0.5-0.8g/cc. The method for preparing the electromagnetic wave absorber containing ferric powder comprises the following steps of (1) uniformly mixing liquid resin with ferric powder; and (2) curing and cooling to obtain the electromagnetic wave absorber containing ferric powder, wherein the apparent density of the ferric powder is 0.5-0.8g/cc. The weight per unit area of the electromagnetic wave absorber containing ferric powder is lower such that satisfies the demands of light weight and thin thickness for materials in the technology industry.

Description

201006872 IX. Description of the Invention: [Technical Field] The present invention relates to an electromagnetic wave absorbing material and a preparation method thereof, and particularly to an electromagnetic wave absorbing material containing iron powder and a preparation method thereof, which are applied to absorbing electromagnetic waves field. [Prior Art] The manufacturing method of the dielectric electromagnetic wave absorbing material described in the Republic of China Patent No. 469283 is to add conductive carbon black, carbon powder, conductive fibers, and hollow glass ginseng balls to a liquid polyurethane resin (PU) resin. Microballoons), which are mixed into a slurry semi-finished product by a two-stage special device, and then the semi-finished product is made into an electromagnetic wave absorbing material by a suitable mold, but the manufacturing method is mainly because the viscosity of the mixed slurry is first mixed with the resin by the resin. Specially designed 3〇〇〇_6〇〇〇rpm high-speed grinding machine disperses, then add carbon powder, conductive fiber and hollow ball. At this time, the viscosity of the slurry is greatly increased, and the low-speed high-viscosity mixer with 3〇〇_6〇〇rpm is used instead. After fully mixing, it is coated into a test piece, which has the disadvantages of complicated process and equipment. The improved Salisbury Screen type electromagnetic wave absorbing material declared in the Republic of China Patent No. 567643, wherein the first layer is an electrically homogeneous lossy material, and the second layer is a low dielectric constant material which is a composite of two materials and an electromagnetic wave combined with a reflective layer. Absorbent material, but because it is a three-layer material, it is more complicated to manufacture than a single-layer material. The Republic of China Patent No. 566077 states that electromagnetic wave absorbing materials are made of multi-layer hollow carbon spheres ❿ 5-50wt% mixed resin, but currently multi-layer hollow carbon spheres are mostly laboratory products, which are expensive and do not meet the needs of mass production.

At present, the iron powder used in some electromagnetic wave absorbing materials is mainly spherical carbonyl iron powder, the average particle diameter is about 1-10 Microns, the iron powder has a high specific gravity and the spherical iron powder has a large apparent density, and the electromagnetic wave containing the spherical iron powder. In the formula of the absorbent material, the iron powder is added to be more than 7% by weight to make a material with a loss of reflection of the book. Therefore, the weight per unit area of the electromagnetic wave absorbing material is too high, and the demand for the material is light and thin. Q In summary, the present inventors provide an electromagnetic wave absorbing material containing iron powder and a preparation method thereof, which can solve the complicated process and equipment of the prior art, the high price does not meet the demand of mass production, and the unit weight of the electromagnetic wave absorbing material is too high. , does not meet the lack of demand for light and thin materials in the technology industry 201006872

[Summary of the Invention] The demand for light and thin. The object of the present invention is that the electromagnetic wave absorbing material of the iron-containing powder has a low basis weight, so that it can knock the technology industry material, and the other object of the present invention is to provide An electromagnetic ship (four) containing iron powder and a preparation method thereof, the preparation method of the electromagnetic wave absorber containing iron powder has the advantages of a simple process and a required equipment. ❹

Another purpose of the soil is to provide an electromagnetic wave absorbing material containing iron powder and a preparation method thereof, which are low in price and can meet the demand for mass production. The invention provides a kind of electric hybrid material containing Lin and its method of making money. 5 克。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。. The preparation of the electromagnetic powder containing iron powder (4) includes: (1) uniformly mixing the resin and the iron powder, and (2) obtaining the electromagnetic wave absorption product containing the iron powder after the cooling is matured; wherein the apparent density of the iron powder is 〇. 5~〇. 8 g/cc. For a better understanding and understanding of the technical features and the efficacies of the present invention, the preferred embodiments and the detailed description are as follows: [Embodiment] The present invention includes An electromagnetic wave absorber of iron powder comprising: 4 〇 to 7 〇 by weight of a resin; and 30 to 60% by weight of iron powder. The iron powder is coral-like or staghorn-shaped. The apparent density of the iron powder is 〇5 to 8.8 g/cc and the average particle diameter of the iron powder is 30 to 60 μm. The iron powder preferably has an apparent density of 0.53 g/cc and preferably has an average particle diameter of 43.0 μm. The resin is one selected from the group consisting of epoxy resins, polyamine phthalic acid resins, polymethacrylate resins, enamel resins, and polyester resins. And the weight percentage of strontium iron powder is better than 201006872, which is 42~50%. 'The steps thereof include (as shown in the first method for preparing an electromagnetic wave absorber containing iron powder according to the present invention): S11 is a mixture of a liquid resin and an iron powder to obtain an electromagnetic wave absorbing composition containing iron powder; and S12 is matured and cooled. That is, an electromagnetic wave absorbing material containing iron powder is obtained. The iron powder is coral or staghorn.

❿ The electromagnetic wave absorbing material of the iron powder comprises 4 〇 to 7 〇 by weight of the resin and 30 to 60% by weight of the iron powder. The step sn further includes a step of filling the mold. The electromagnetic wave absorbing material of the iron powder has a thickness of 0.5 to 5.0 Å and a reflection loss of 10 dB or more in a frequency range of 2 to 18 GHz. The preferred thickness of the electromagnetic wave absorbing material containing the iron powder is the SEM image of the coral iron powder used in the present invention. The SEM image is as shown in the second figure, and the method is as follows: Deflated _ 2 ~ 4 small _ get, the appearance of the shape such as coral or antler strips more than the shape of the visual density of 0.5 ~ G.8gAx, measured by the CGulterLS-230 laser particle size analyzer, the average particle size of 3 〇 ~6〇μιη. In a preferred embodiment of the present invention, a coral-like iron powder (a raw material produced by the present invention, No. 2, apparent density 〇.53 g/cc, average particle diameter 43·0 μπι) and a comparative example are attached to the epoxy resin. Add carbonyl iron powder as a filler to the oxygen resin, and then mix the slurry with a general three-roller machine (the gap of the roller is 0·1 mm), and then pour the slurry into a metal mold of 1 $ cmx 1 $ cm. The aluminum plate was placed up and down, clamped with a clip, and baked at 80 ° C for 2 hours, and then taken out. After cooling, the aluminum plate was removed to take out the electromagnetic wave absorbing material, and the thickness and weight were measured after modification. The microwave loss loss (Return Loss) measurement method uses the free space test method 'frequency range (2-18 GHz), using the microwave network analyzer Hp 8722ES and the Damaskos free space measurement fixture 'with the same test piece size 15cmxl5cm metal piece on the test 201006872 position 'first correction level, adjust the antenna incident angle (21.) to measure the original reflection amount, then change the test piece and use the metal piece as the reflection surface to re-measure the reflection loss attenuation intensity of the test piece, reflection The greater the loss, the better the electromagnetic wave absorption effect. In order to describe the present invention in more detail, the following specific examples and comparative examples are described below. Table 1 shows the source and specifications of the magnetic filler used in the examples and comparative examples of the present invention: Table 1 Magnetic fillers used in the examples and comparative examples of the present invention. Source name Coral iron powder The average particle diameter of the invention is 43.0. Microns apparent density: 0.53 g/cc carbonyl iron powder (S3700) US International Specialty Products company average particle size: 2.5 microns apparent density: 2.5g/cc Example 1 50.0g liquid epoxy resin and coral iron powder 5〇〇 g Add 25 〇ml mixing container total amount of IGGg), first win _2 minutes with the winning stick, then use the same three-roller machine to make the material mix 5 times, then take 7 〇〇g medicine Pour the medicine into the ❿em metal fresh towel' for 8 hours at 8G °C, and then measure the weight to 6 曰〇. 〇g 'thickness is LW' unit area weight is 2 7Kg / _, The microwave reflection loss is measured as shown in the second figure. The two peaks are at 1G() GH2, and the reflection loss is 144. Comparative Example 1 Add 6 〇.〇g liquid epoxy resin and several base iron powder M〇〇g to 25-mixed mixing container (total = 200g) 'Firstly, with a lininger 2 minute gamma general three-roller After mixing the drug for 10 times, take 130.0 g of the drug, collect the drug into a 15 · 5 (10) metal mold, and bake at 8 ° C for 2 hours, then take out the test piece. After modification, the weight is ii3 〇 g, the thickness is 2 force surface, the weight per unit area is 5.GKg/mxm, the microwave reflection loss measurement is as shown in the fourth figure, the high peak is at 10 lGHz, and the reflection loss is 15 6 dB. 201006872 _ Example 2 Add 58.0g liquid epoxy resin and coral iron powder 42 〇g to 25〇ml mixing container (total dosage 100g) 'First stir with stirring rod for 1-2 minutes, then use general three roller After the machine is mixed for 5 times, the slurry is evenly mixed, and then the sample is taken into a 15 cm x 15 cm metal mold. The sample is taken at 8 ° C for 2 hours, and the test piece is taken out. 44.0g, thickness llmm, weight per unit area is 2.0Kg/mxm, microwave reflection loss measurement as shown in the fifth figure, high peak at 14.4GHz, and its reflection loss is 16 4dB. Comparative Example 2 φ 30.0g of liquid epoxy resin and carbonyl iron powder 7〇.〇g were added to a 250ml mixing container (total amount of 100g), first stirred with a stir bar for _2 minutes, then with a general three-roller machine After mixing the mixture for 5 times, 85.0 g of the slurry was taken, and the slurry was poured into a 5 cm x 15 cm metal mold, and baked for 8 hours at 8 〇t>c, and the test piece was taken out and measured. The weight is 75 〇g, the thickness is 12mm, and the weight per unit area is 3.3Kg/mxm. The microwave reflection loss is measured as shown in the sixth figure. The high peak is at 15.2GHz and the reflection loss is 15.ldB. Example 3 100. 〇g liquid epoxy resin and mushroom iron powder 100.Og was added to a 250ml mixing container (total dosage of 200g), first stirred with a stir bar for _2 minutes, then with a general three-roller After mixing the φ slurry for a uniform time, take 130. 〇g of the slurry, pour the slurry into a 15 cm><15 cm metal mold, and dry at 80 °C for 2 hours, then take out the test piece. After the modification, the measured weight was 113 〇g, the thickness was 25 mm, and the weight per unit area was 5.0 Kg/mxm. The microwave reflection loss was measured as shown in the seventh figure, and the high peak was at 6.0 GHz, and the reflection loss was 23.8 dB. Comparative Example 3 60.0 g of liquid epoxy resin and 14 gram of carbonyl iron powder were added to a 25 〇ml mixing container (total amount of 200 g), first stirred with a stir bar for _2 minutes, and then with a general three-roller machine. After mixing the mixture for 5 times, 185.0 g of the slurry was taken, and the slurry was poured into a 15 cm x 15 cm metal mold, and the test piece was taken out after drying at 80 ° C for 2 hours. After the modification, the measured weight was 178 〇. g, the thickness is 3 〇mm, the weight per unit area is 7.9Kg/mxm, the microwave reflection loss is measured as shown in the eighth figure, and the high peak at 201006872 6.0GHz 'the reflection loss is 11 9dB. Example 4 Add l〇〇.〇g liquid epoxy resin and butterfly iron powder 100.Og into a 250ml mixing container (total dosage of 20〇g), first stir with a stir bar for 1-2 minutes, then Generally, the three-roller machine mixes the mixture 5 times to make the slurry evenly mixed, then take 194.0 g of the slurry, pour the slurry into a 15 cm x 15 cm metal mold, and dry it at 80 ° C for 2 hours, then take out the test piece and modify it. The measured weight was 1804 g, the thickness was 44 mm, the weight per unit area was 8.0 Kg/mxm, and the microwave reflection loss measurement was as shown in the ninth figure. The high peak value was 3.0 GHz, and the reflection loss was i4.5 dB. Comparative Example 4 120.0 g of liquid epoxy resin and carbonyl iron powder 28 〇.〇g were added to a 500 m mixing container (total amount of 40 〇g) 'First stir with a stirring bar for 1-2 minutes' and then with a general three roller After the machine was mixed 5 times to mix the slurry evenly, 360.0 g of the slurry was taken, and the slurry was poured into a 15 cm x 15 cm metal mold, and the test piece was taken out after drying at 80 ° C for 2 hours. After the modification, the weight was measured. 344 〇g, thickness 62mm, weight per unit area 15_3Kg/mxm 'The microwave reflection loss measurement is shown in the tenth figure, and the high peak value is 3*0GHz' and its reflection loss is 14.2dB. Tables 2 to 5 show the above-mentioned embodiments and comparative examples of the present invention and the British BAE products in the same frequency band of X (8-12 GHz), Ku (12-18 GHz), C (4-8 GHz), S (2-4 GHz). The comparison table of ^ is found in the table to show that the reflection loss of the test piece in the same frequency band is similar to or larger than the reflection loss of the test piece of the comparative example, and the electromagnetic wave absorption product containing the iron powder of the present invention has a better electromagnetic wave absorption effect. Moreover, the thickness and the unit area weight of the test piece are smaller than those of the comparative test piece, and the thickness of the test piece and the BAE company of the embodiment of the present invention are superior to those of the BAE company except that the thickness of the s-band is slightly larger. BAE products. 201006872 ❿

Table 2 Comparison of Example 1 with Eater and BAE Company Example 1 Comparative Example 1 BAE Model WMX3 Thickness (mm) 1.5 2.0 2.3 Unit Weight (Kg/mxm) 2.7 5.0 7.3 High Reflection Peak Loss (GHz /dB) 10.0/14.4 —------ 10.1/15.6 — Band ------__ XX Table 3 Example 2 and Comparative Example 2 and BAE Company Product Comparison Table Example 1 Comparison Example 1 BAE Model WMX3 Thickness (mm) 1.1 1.2 2.0 Weight per unit area (Kg/mxm) 2.0 3.3 6.0 High peak value of reflection loss (GHz/dB) 14.4/16.4 —-一·_. — · 15.2/15.1 — Band Ku Ku Ku Table 4 Implementation Example 3 J 3^BAE product comparison table Example 1 Comparative example 1 BAE company model WMX3 Thickness (mm) 2.5 ～ 3.0 3.3 Unit weight (Kg/mxm) 5.0 7.9 15.5 High reflection loss peak (GHz/dB) 6.0/ 23.8 ^' 6.0/11.9 - Band CCC Table 5 Example 4 J Comparison Example 4 and BAE Company r Right Comparison Table 1 Comparison Example 1 BAE Model WMX3 Thickness (mm) 4.4 6.2 3.8 Unit Weight (Kg /mxm) 8.0 15.3 17.0 High reflection loss per value (GHz/dB) Band 3.0/14.5, ^ 3.0/14.2 ~S ~ S In summary, the present invention The following advantages: the present invention contain iron slave electromagnetic closing weight per unit area was low, the seam ride-technology industry materials 201,006,872 material lighter, thinner demand. 2·: Round full of secrets (four) inspection fine Gane tender simple price low i iron electromagnetic wave Weiwu and its preparation method, * New Zealand line ball, so its low price, can meet the needs of mass production. National car! For the stuffy, progressive material supply «On the Tong, should meet my quasi-patent, to the sense of 3 elements undoubtedly, blasting the invention patent application, praying for the Bureau

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, and the equivalents and modifications of the features and spirits described in the claims of the present invention should be included. In the 憎 special fiber circumference of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a flow chart showing the steps of a method for preparing an electromagnetic wave containing iron powder according to the present invention. The second figure shows the SEM image of the iron powder of the present invention. The third figure is a characteristic diagram of the sample wave reflection loss of the electromagnetic contact of the flour of the present invention. The fourth graph is a microwave reflection loss characteristic diagram of the electromagnetic wave absorber of the iron powder containing the iron powder of the present invention. Fig. 5 is a graph showing the microwave reflection loss characteristics of the electromagnetic wave absorber containing iron powder according to Example 2 of the present invention. Fig. 6 is a graph showing the microwave reflection loss characteristics of the electromagnetic wave absorbing material containing carbonyl iron powder of Comparative Example 2 of the present invention. Fig. 7 is a graph showing the microwave reflection loss characteristics of the electromagnetic wave absorbing material containing iron powder according to Example 3 of the present invention. Fig. 8 is a graph showing the microwave reflection loss characteristics of the electromagnetic wave absorbing material containing carbonyl iron powder of Comparative Example 3 of the present invention. 12 201006872 The ninth graph is a graph showing the microwave reflection loss of the electromagnetic wave absorber containing iron powder according to Example 4 of the present invention. Fig. 10 is a graph showing the microwave reflection loss characteristics of the electromagnetic wave absorbing material containing carbonyl iron powder of Comparative Example 4 of the present invention. [Main component symbol description] None ❹

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Claims (1)

201006872 X. Patent application scope: 1. An electromagnetic wave absorber containing iron powder, which comprises: 40 to 70 weight percent resin; and 30 to 60 weight percent iron powder; wherein the iron powder has an apparent density of 0.5~ 0.8 g/cc. 2. = Please refer to the electromagnetic wave absorber of iron powder according to item i of the patent scope, wherein the iron is in the shape of a scorpion or an antler. ❹ 3. The electromagnetic wave absorber of the iron powder according to claim 1, wherein the average grain control of the iron is 30 to 60 μm. 4. The electromagnetic wave absorber of the iron powder according to claim i, wherein the iron powder preferably has an apparent density of 0.53 g/cc. 5. The electromagnetic wave containing iron powder according to item 2 of the patent application shed. The absorbent, wherein the iron powder preferably has an average particle diameter of 43.0 μm. 6. The electromagnetic wave absorbing material of the iron powder according to claim i, wherein the resin is selected from the group consisting of epoxy resin, polyurethane resin, polydecyl acrylate resin, Shixi resin and poly vinegar One of the groups consisting of resins. 7. The electromagnetic wave absorbing material of the iron powder according to claim 1, wherein the iron powder preferably has a weight percentage of 42 to 50%. 8. A method for preparing an electromagnetic wave absorbing material containing iron powder, the steps comprising: (1) uniformly mixing the liquid resin and the iron powder; and (2) obtaining an electromagnetic wave absorbing material containing iron powder after curing and cooling; The iron powder has an apparent density of 0.5 to 0.8 g/cc. 9. The method for preparing an electromagnetic wave absorbing material containing iron powder according to claim 8, wherein the electromagnetic wave absorbing material of the iron powder in the step (2) comprises 40 to 70% by weight of the resin and 30 to 60 parts by weight. Percentage of iron powder. 10. The method for preparing an electromagnetic wave absorbing material containing iron powder according to claim 9, wherein the iron powder preferably has a weight percentage of 42 to 50%. 14 201006872 • π·如巾料” _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 12. The method for preparing an electromagnetic wave absorbing material containing iron powder according to claim 8, wherein the thickness of the electromagnetic wave absorbing material of the iron powder in the step (2) is 〇·5 to 5.0 mm′ and is in 2~ The frequency range of 18 GHz has a reflection loss of more than 1 〇 dB. 13. The method for preparing an electromagnetic wave absorbing material containing iron powder according to the invention of claim U, wherein a preferred thickness of the electromagnetic wave absorbing material containing the iron powder is Μ 5 _. 14. The method for preparing an electromagnetic wave absorbing material containing iron powder according to claim 8, wherein the preferred apparent density of the iron powder in the step (1) is 0.53 g/cc and the iron powder is _ The particle size is 30 to 60 μm. 15. The method for preparing an electromagnetic wave absorbing material containing iron powder according to claim 14, wherein the iron powder preferably has an average particle diameter of 43·0 μm. 16. The method for preparing an electromagnetic wave absorber containing iron powder according to claim 8, wherein the liquid resin in the step (1) is selected from the group consisting of an epoxy resin, a polyurethane resin, and a polymethacrylic acid. One of a group consisting of an ester resin, a enamel resin, and a polyester resin. 17. The method for preparing an electromagnetic wave absorbing material containing iron powder according to claim 8, wherein the iron powder in the step (1) is coral-like or staghorn-shaped. 15