Ka-band wave-absorbing film and preparation method thereof

Abstract

The invention relates to the technical field of magnetic materials, in particular to a Ka-band wave-absorbing film and a preparation method thereof. Comprising 60-70% of polyester, 1-4% of a dispersant, 20-40% of an absorbent, 5-15% of an antioxidant, 1-2% of a flow improver and 1-2% of a processing lubricant. The preparation method comprises the following steps: mixing the raw materials, and uniformly mixing the components to obtain mixed powder; carrying out casting treatment on the mixed powder to obtain a cast film; wherein the thickness of the cast film is 0.7 to 1mm; cutting the cast film to obtain a wave-absorbing film; the wave-absorbing film can be used for a Ka wave band, and the reflectivity of the film at the frequency band of 18-26 GHz is less than or equal to-7 dB; through the mode, error information caused by mutual interference of equipment is prevented, and the integrity of signals is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of magnetic materials, and in particular to a Ka-band absorbing film and a preparation method thereof. Background Art

[0002] In recent years, with the development of wireless communication systems and the popularization of IoT devices, digital devices have been widely used. Among them, the Ka band has become the preferred working frequency band for high-speed, high-bandwidth communications; however, its device size is small, and it is most likely to cause excessive electromagnetic radiation, which is easily interfered or intercepted by the outside world. Therefore, for the security of communication, its radiation power must be strictly controlled; at the same time, 6G devices are beginning to be used in large quantities in the Ka band, which is likely to cause interference between devices and produce error information.

[0003] In summary, it is very necessary to propose a Ka-band absorbing film and a preparation method thereof to prevent interference between devices and generate erroneous information and ensure signal integrity. Summary of the invention

[0004] The object of the present invention is to provide a Ka-band absorbing film and a preparation method thereof, so as to prevent the interference between devices and generate erroneous information and ensure the integrity of the signal.

[0005] To achieve the above purpose, the present invention adopts a Ka-band absorbing film, which comprises 60-70% polyester, 1-4% dispersant, 20-40% absorbent, 5-15% antioxidant, 1-2% flow improver and 1-2% processing lubricant.

[0006] The absorbent is a mixture of iron alloy powder and pigment carbon black; the iron alloy powder is composed of one or more of FeSi and FeNi.

[0007] Wherein, the polyester is PBT powder.

[0008] The antioxidant is a mixture of high molecular weight hindered phenol 1098 and phosphite auxiliary antioxidant 618.

[0009] Wherein, the flow improver is silicone masterbatch.

[0010] Wherein, the dispersant is titanate.

[0011] Wherein, the processing lubricant is magnesium stearate.

[0012] The present invention also provides a method for preparing a Ka-band absorbing film, comprising the following steps:

[0013] Mixing raw materials, uniformly mixing the components to obtain mixed powder;

[0014] The mixed powder is subjected to a casting process to obtain a casting film; wherein the thickness of the casting film is 0.7 to 1 mm;

[0015] The cast film is cut to obtain an absorbing film.

[0016] The invention discloses a wave absorbing film for Ka band and a preparation method thereof. The raw materials are mixed to uniformly mix 60-70% of polyester, 1-4% of dispersant, 20-40% of absorbent, 5-15% of antioxidant, 1-2% of flow improver and 1-2% of processing lubricant to obtain the mixed powder; the mixed powder is subjected to a casting process to obtain the cast film; the thickness of the cast film is 0.7-1mm; the cast film is attached to a metal plate, and the reflectivity of the film sample in Ka band is measured by an arch reflection test method, and the reflectivity is ≤-7dB; the cast film is cut to obtain the wave absorbing film, and the wave absorbing film can be used in Ka band, and the reflectivity of the film in 18-26GHz frequency band is ≤-7dB; through the above method, it is achieved to prevent the interference between devices to generate error information and ensure the integrity of the signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a flow chart of the steps of the method for preparing the Ka-band absorbing film of the present invention. DETAILED DESCRIPTION

[0019] See also Figure 1 , Figure 1 It is a flow chart of the steps of the method for preparing the Ka-band absorbing film.

[0020] The invention provides a wave absorbing film for Ka band, which comprises 60-70% polyester, 1-4% dispersant, 20-40% absorbent, 5-15% antioxidant, 1-2% flow improver and 1-2% processing lubricant.

[0021] Furthermore, the absorbent is a mixture of iron alloy powder and pigment carbon black; wherein the iron alloy powder is composed of one or more of FeSi and FeNi.

[0022] Furthermore, the polyester is PBT powder.

[0023] Furthermore, the antioxidant is a mixture of high molecular weight hindered phenol 1098 and phosphite auxiliary antioxidant 618.

[0024] Furthermore, the flow improver is silicone masterbatch.

[0025] Furthermore, the dispersant is titanate.

[0026] Furthermore, the processing lubricant is magnesium stearate.

[0027] The present invention also provides a method for preparing a Ka-band absorbing film, comprising the following steps:

[0028] S1: Mixing raw materials, uniformly mixing the components to obtain mixed powder;

[0029] S2: performing a casting process on the mixed powder to obtain a cast film; wherein the thickness of the cast film is 0.7 to 1 mm;

[0030] S3: cutting the cast film to obtain an absorbing film.

[0031] In this embodiment, the raw materials are first mixed, and 60-70% polyester, 1-4% dispersant, 20-40% absorbent, 5-15% antioxidant, 1-2% flow improver and 1-2% processing lubricant are uniformly mixed to obtain the mixed powder. The absorbent is a mixture of iron alloy powder and pigment carbon black; the iron alloy powder is one or more of FeSi and FeNi; the polyester is PBT powder; the antioxidant is a mixture of high molecular hindered phenol 1098 and phosphite auxiliary antioxidant 618; the flow improver is silicone masterbatch; the dispersant is titanate; and the processing lubricant is magnesium stearate. Then the mixed powder is subjected to a casting process to obtain the cast film; wherein the thickness of the cast film is 0.7-1mm. The cast film is attached to a metal plate, and the reflectivity of the film sample in the Ka band is measured by an arch reflection test method, and the reflectivity is ≤-7dB. Finally, the cast film is cut to obtain the absorbing film, which can be used in the Ka band, and the reflectivity of the film in the 18-26 GHz frequency band is ≤-7dB. Through the above method, it is possible to prevent the devices from interfering with each other and generating erroneous information, thereby ensuring the integrity of the signal.

[0032] Taking Examples 1 to 5 as examples, the raw material components of the Ka-band absorbing films of Examples 1 to 5 are shown in Table 1:

[0033]

[0034]

[0035] Table 1. Raw material composition of Ka-band absorbing film in Examples 1 to 5 (unit: %)

[0036] Example 1

[0037] Weigh 54% PBT powder, 3% dispersant, 30% FeSi alloy powder, 8% 1098 antioxidant, 2% 1618 auxiliary antioxidant, 1% silicone masterbatch, 2% calcium stearate, use a high-speed mixer, stir at 500RPM, temperature 80℃ for 30min, then use an extrusion casting machine to extrude and cast the stirred uniform powder to obtain a noise suppression film with a film thickness of 1.0mm. Cut the film into square sheets with a side length of 300mm, and test the material's reflectivity in the Ka band to be -8dB.

[0038] Example 2

[0039] Weigh 54% PBT powder, 3% dispersant, 20% FeSi alloy powder, 10% FeNi powder, 8% 1098 antioxidant, 2% 1618 auxiliary antioxidant, 1% silicone masterbatch, 2% calcium stearate, use a high-speed mixer, stir at 500RPM, temperature 80℃ for 30min, then use an extrusion casting machine to extrude and cast the stirred uniform powder to obtain a noise suppression film with a film thickness of 1.0mm. Cut the film into square sheets with a side length of 300mm, and test the reflectivity of the film material in the Ka band to be -11dB.

[0040] Example 3

[0041] Weigh 54% PBT powder, 3% dispersant, 15% FeSi alloy powder, 15% FeNi powder, 8% 1098 antioxidant, 2% 1618 auxiliary antioxidant, 1% silicone masterbatch, 2% calcium stearate, use a high-speed mixer, stir at 500RPM, temperature 80℃ for 30min, then use an extrusion casting machine to extrude and cast the stirred uniform powder to obtain a noise suppression film with a film thickness of 1.0mm. Cut the film into square sheets with a side length of 300mm, and test the reflectivity of the film material in the Ka band to be -12dB.

[0042] Example 4

[0043] Weigh 54% PBT powder, 3% dispersant, 15% FeSi alloy powder, 5% FeNi powder, 10% carbon black pigment, 8% 1098 antioxidant, 2% 1618 auxiliary antioxidant, 1% silicone masterbatch, 2% calcium stearate, stir at 500RPM and 80℃ for 30min with a high-speed mixer, then use an extrusion casting machine to extrude and cast the stirred uniform powder to obtain a noise suppression film with a film thickness of 1.0mm. Cut the film into square sheets with a side length of 300mm, and test the reflectivity of the film material in the Ka band to be -14dB.

[0044] Example 5

[0045] Weigh 54% PBT powder, 3% dispersant, 10% FeSi alloy powder, 5% FeNi powder, 15% carbon black pigment, 8% 1098 antioxidant, 2% 1618 auxiliary antioxidant, 1% silicone masterbatch, 2% calcium stearate, use a high-speed mixer, stir at 500RPM / min, temperature 80℃ for 30min, then use an extrusion casting machine to extrude and cast the stirred uniform powder to obtain a noise suppression film with a film thickness of 1.0mm. Cut the film into square sheets with a side length of 300mm, and test the reflectivity of the film material in the Ka band to be -17dB.

[0046] In summary, the absorbing film can be used in the Ka band, and the reflectivity of the film in the 18-26 GHz frequency band is ≤-7dB; it can prevent the devices from interfering with each other and generating erroneous information, thereby ensuring the integrity of the signal.

[0047] What is disclosed above is only a preferred embodiment of the present invention, and it certainly cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiment and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A Ka-band absorbing film, characterized in that: The invention is prepared by comprising the following raw materials in percentage by weight: Polyester 60-70%, dispersant 1-4%, absorbent 20-40%, antioxidant 5-15%, flow improver 1-2% and processing lubricant 1-2%.

2. The Ka-band absorbing film according to claim 1, characterized in that: The absorbent is a mixture of iron alloy powder and carbon black pigment; wherein the iron alloy powder is one or more of FeSi and FeNi.

3. The Ka-band absorbing film according to claim 1, characterized in that: The polyester is PBT powder.

4. The Ka-band absorbing film according to claim 1, characterized in that: The antioxidant is a mixture of high molecular hindered phenol 1098 and phosphite auxiliary antioxidant 618.

5. The Ka-band absorbing film according to claim 1, characterized in that: The flow improver is silicone masterbatch.

6. The Ka-band absorbing film according to claim 1, characterized in that: The dispersant is titanate.

7. The Ka-band absorbing film according to claim 1, characterized in that: The processing lubricant is magnesium stearate.

8. A method for preparing a Ka-band absorbing film, comprising preparing the Ka-band absorbing film as claimed in claim 1, characterized in that: The steps include: Mixing raw materials, uniformly mixing the components to obtain mixed powder; The mixed powder is subjected to a casting process to obtain a casting film; wherein the thickness of the casting film is 0.7 to 1 mm; The cast film is cut to obtain an absorbing film.

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