CN100508715C - A novel electromagnetic shielding composite material and its preparation method - Google Patents
A novel electromagnetic shielding composite material and its preparation method Download PDFInfo
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- CN100508715C CN100508715C CNB2006100811647A CN200610081164A CN100508715C CN 100508715 C CN100508715 C CN 100508715C CN B2006100811647 A CNB2006100811647 A CN B2006100811647A CN 200610081164 A CN200610081164 A CN 200610081164A CN 100508715 C CN100508715 C CN 100508715C
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- 239000002131 composite material Substances 0.000 title claims abstract description 33
- 238000002360 preparation method Methods 0.000 title claims abstract description 11
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims abstract description 36
- 239000002033 PVDF binder Substances 0.000 claims abstract description 34
- 229920002981 polyvinylidene fluoride Polymers 0.000 claims abstract description 34
- 229910000859 α-Fe Inorganic materials 0.000 claims abstract description 26
- 239000002245 particle Substances 0.000 claims abstract description 12
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 11
- 239000002184 metal Substances 0.000 claims abstract description 5
- 229910052751 metal Inorganic materials 0.000 claims abstract description 5
- 238000007731 hot pressing Methods 0.000 claims abstract description 3
- 239000000843 powder Substances 0.000 claims description 10
- 239000000203 mixture Substances 0.000 claims description 8
- 239000004615 ingredient Substances 0.000 claims description 7
- 238000000034 method Methods 0.000 claims description 7
- 229910010272 inorganic material Inorganic materials 0.000 claims description 4
- 239000011147 inorganic material Substances 0.000 claims description 4
- 238000000465 moulding Methods 0.000 claims description 4
- 239000011812 mixed powder Substances 0.000 claims description 3
- 238000003756 stirring Methods 0.000 claims description 3
- 239000000463 material Substances 0.000 abstract description 14
- 230000000694 effects Effects 0.000 abstract description 5
- 230000005291 magnetic effect Effects 0.000 abstract description 5
- 239000003302 ferromagnetic material Substances 0.000 abstract 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 23
- 229920000642 polymer Polymers 0.000 description 8
- 238000011161 development Methods 0.000 description 5
- 229910001053 Nickel-zinc ferrite Inorganic materials 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000005294 ferromagnetic effect Effects 0.000 description 2
- 239000006249 magnetic particle Substances 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910021393 carbon nanotube Inorganic materials 0.000 description 1
- 239000002041 carbon nanotube Substances 0.000 description 1
- 239000011231 conductive filler Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 230000005307 ferromagnetism Effects 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 238000004377 microelectronic Methods 0.000 description 1
- 229920000620 organic polymer Polymers 0.000 description 1
- 239000002861 polymer material Substances 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
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Abstract
Description
技术领域 technical field
本发明属于电磁屏蔽材料领域，特别涉及由导电填料和铁磁性填料组成、制备温度低、工艺简便的一种新型电磁屏蔽复合材料及其制备方法。The invention belongs to the field of electromagnetic shielding materials, and in particular relates to a novel electromagnetic shielding composite material which is composed of conductive filler and ferromagnetic filler, has low preparation temperature and simple process and a preparation method thereof.
背景技术 Background technique
随着无线通讯技术的飞速发展，电磁干扰，电磁信息泄露，电磁环境污染等问题也变得越来越严重。目前，几乎所有的电子和电器设备都不可避免的受到电信号和磁信号的干扰。因此，电磁干扰的问题受到广泛的关注，电磁屏蔽材料的研究也成为一个热点，对于国民经济的可持续发展战略具有重要的意义。相对于传统的金属类屏蔽材料，目前的电磁屏蔽材料向着轻、薄、易加工的方向发展，以适应微电子工业中无源器件的发展。With the rapid development of wireless communication technology, problems such as electromagnetic interference, electromagnetic information leakage, and electromagnetic environmental pollution have become more and more serious. At present, almost all electronic and electrical equipment are inevitably disturbed by electrical and magnetic signals. Therefore, the problem of electromagnetic interference has been widely concerned, and the research on electromagnetic shielding materials has also become a hot spot, which is of great significance to the sustainable development strategy of the national economy. Compared with the traditional metal shielding materials, the current electromagnetic shielding materials are developing in the direction of lightness, thinness and easy processing, so as to adapt to the development of passive devices in the microelectronics industry.
近几年来，电磁屏蔽复合材料方面的研究集中在两类材料。第一类主要是在聚合物中添加导电颗粒，如银，铜，镍，铁或碳纳米管等，通过在聚合物基体内形成导电通路来提高聚合物的导电性，从而提高电磁屏蔽效能。这类屏蔽材料主要的问题是，如果要到达较高的屏蔽效能则需要较高的成本，同时只具有单一的电屏蔽的功能，且反射损耗太大，容易造成二次电磁干扰。In recent years, research on electromagnetic shielding composite materials has focused on two types of materials. The first type is mainly to add conductive particles to the polymer, such as silver, copper, nickel, iron or carbon nanotubes, etc., to improve the conductivity of the polymer by forming a conductive path in the polymer matrix, thereby improving the electromagnetic shielding effect. The main problem of this kind of shielding material is that if it wants to achieve higher shielding effectiveness, it needs higher cost. At the same time, it only has a single function of electric shielding, and the reflection loss is too large, which is easy to cause secondary electromagnetic interference.
第二类屏蔽材料主要是把软磁性材料添加到聚合物中来实现电磁屏蔽。例如，将镍锌铁氧体、六角铁氧体颗粒或其他磁性颗粒添加到聚合物中。由于添加颗粒的电阻较高，复合材料的导电性不够理想，使得这类屏蔽材料的屏蔽效能不够理想。The second type of shielding material mainly adds soft magnetic materials to polymers to achieve electromagnetic shielding. For example, nickel zinc ferrite, hexagonal ferrite particles or other magnetic particles are added to the polymer. Due to the high resistance of the added particles, the electrical conductivity of the composite material is not ideal, so that the shielding effectiveness of this type of shielding material is not ideal.
最近，有人将导电颗粒和磁性颗粒同时添加到聚合物中制备了一类兼备电屏蔽和磁屏蔽的复合材料。例如把镍颗粒和羰基铁或镍颗粒和镍锌铁氧体添加到聚合物中，但是这类材料只能在低频范围较好的屏蔽电磁波。通讯技术向更高频率发展的趋势迫切需要发展在更高频率更宽范围内也能屏蔽电磁波的屏蔽材料。Recently, someone added conductive particles and magnetic particles to polymers to prepare a class of composite materials with both electrical and magnetic shielding. For example, nickel particles and carbonyl iron or nickel particles and nickel zinc ferrite are added to the polymer, but these materials can only shield electromagnetic waves well in the low frequency range. The development trend of communication technology to higher frequencies urgently requires the development of shielding materials that can also shield electromagnetic waves at higher frequencies and in a wider range.
本发明中我们以六角铁氧体相、金属相和有机聚合物组分构成新型的三相复合材料，开发出了一系列的电磁屏蔽复合材料。在这类材料中，高电阻的六角铁氧体不仅起到绝缘相的作用，将高电导的镍颗粒隔离，有效地减小了涡流效应对复合材料铁磁性的影响，而且起到铁磁体的作用，显著地提高了复合材料的磁性。同时，这类材料的应用频率范围大大提高，在8.2-12.4GHz范围内，总电磁屏蔽效能在30-70dB之间，具有很好的应用前景。In the present invention, we use hexagonal ferrite phase, metal phase and organic polymer components to form a new three-phase composite material, and develop a series of electromagnetic shielding composite materials. In this type of material, the high-resistance hexagonal ferrite not only acts as an insulating phase to isolate the high-conductivity nickel particles, effectively reducing the influence of the eddy current effect on the ferromagnetism of the composite material, but also acts as a ferromagnet. effect, significantly improving the magnetic properties of the composite material. At the same time, the application frequency range of this kind of material is greatly improved. In the range of 8.2-12.4GHz, the total electromagnetic shielding effectiveness is between 30-70dB, which has a good application prospect.
发明内容 Contents of the invention
本发明提供一种新型的电磁屏蔽复合材料及其制备方法。其特征在于：所述新型电磁屏蔽复合材料包括无机材料：六角铁氧体[如Z型平面六角铁氧体(Ba3Co2Fe23O41，Ba3Co2Fe24O41)或Y型平面六角铁氧体(Ba2Co2Fe115O22，Ba2Co2Fe2O22)]、导电金属镍粉(Ni)，以及聚合物材料：聚偏氟乙烯(PVDF)。其配方体积比为：镍7.5～45％，六角铁氧体5～42.5％，聚偏氟乙烯50％。所述无机材料的粒度为：镍2～3μm，六角铁氧体10～30μm。The invention provides a novel electromagnetic shielding composite material and a preparation method thereof. It is characterized in that: the novel electromagnetic shielding composite material includes inorganic materials: hexagonal ferrite [such as Z-type planar hexagonal ferrite (Ba 3 Co 2 Fe 23 O 41 , Ba 3 Co 2 Fe 24 O 41 ) or Y-type Planar hexagonal ferrite (Ba 2 Co 2 Fe 115 O 22 , Ba 2 Co 2 Fe 2 O 22 )], conductive metal nickel powder (Ni), and polymer material: polyvinylidene fluoride (PVDF). The formula volume ratio is: nickel 7.5-45%, hexagonal ferrite 5-42.5%,
本发明实施的工艺流程如下：The technological process that the present invention implements is as follows:
1)体积配料：按上述体积配方取2～3μm的镍粉7.5～45％，10～30μm的六角铁氧体粉5～42.5％，聚偏氟乙烯50％。1) Volume ingredients: 7.5-45% of nickel powder of 2-3 μm, 5-42.5% of hexagonal ferrite powder of 10-30 μm, and 50% of polyvinylidene fluoride according to the above-mentioned volume formula.
2)配样：将镍粉、聚偏氟乙烯以及铁氧体粉按照上述比例搅拌，混合均匀。2) Sample preparation: Stir nickel powder, polyvinylidene fluoride and ferrite powder according to the above ratio, and mix evenly.
3)成型：将混合均匀的粉末放在粉末压片机上，在温度为180～220℃，压力为10～15MPa的条件下，热压15～20min成型。3) Molding: put the uniformly mixed powder on a powder tablet press, and heat-press for 15-20 minutes under the conditions of temperature 180-220° C. and pressure 10-15 MPa.
本发明的有益效果是：通过简单的复合作用，将铁磁性颗粒和导电颗粒按照一定的体积比填充到聚合物基体中，使得复合材料同时具有优良的电屏蔽和磁屏蔽的特性，得到Ba3Co2Fe23O41-Ni-PVDF和Ba3Co2Fe24O41-Ni-PVDF体系的总屏蔽效能在8.2-12.4GHz范围内为30～70dB；Ba2Co2Fe11.5O22-Ni-PVDF，和Ba2Co2Fe12O22-Ni-PVDF体系的总屏蔽效能在8.2-12.4GHz范围内为30～50dB。上述四种三相复合体系采用简单热压工艺进行材料成型，缩短了制备时间，在短时间内获得了性能良好的电磁屏蔽复合材料。The beneficial effects of the present invention are: through simple composite action, ferromagnetic particles and conductive particles are filled into the polymer matrix according to a certain volume ratio, so that the composite material has excellent characteristics of electric shielding and magnetic shielding at the same time, and Ba 3 The total shielding effectiveness of Co 2 Fe 23 O 41 -Ni-PVDF and Ba 3 Co 2 Fe 24 O 41 -Ni-PVDF systems is 30-70dB in the range of 8.2-12.4GHz; Ba 2 Co 2 Fe 11.5 O 22 -Ni -PVDF, and Ba 2 Co 2 Fe 12 O 22 -Ni-PVDF system, the total shielding effectiveness is 30-50dB in the range of 8.2-12.4GHz. The above four three-phase composite systems adopt a simple hot-pressing process for material molding, which shortens the preparation time and obtains electromagnetic shielding composite materials with good performance in a short time.
附图说明 Description of drawings
图1：三相复合材料的总屏蔽效能随频率的变化规律，其中图1(a)～(d)分别为Ba3Co2Fe23O41-Ni-PVDF，Ba3Co2Fe24O41-Ni-PVDF，Ba2Co2Fe12O22-Ni-PVDF，和Ba2Co2Fe11.5O22-Ni-PVDF三相复合体系。屏蔽效能的单位为dB。Figure 1: The total shielding effectiveness of three-phase composite materials varies with frequency, where Figure 1 (a) to (d) are Ba 3 Co 2 Fe 23 O 41 -Ni-PVDF, Ba 3 Co 2 Fe 24 O 41 -Ni-PVDF, Ba 2 Co 2 Fe 12 O 22 -Ni-PVDF, and Ba 2 Co 2 Fe 11.5 O 22 -Ni-PVDF three-phase composite system. The unit of shielding effectiveness is dB.
图2：三相复合材料的总屏蔽效能，反射屏蔽效能及吸收屏蔽效能随镍/(镍+铁氧体)体积比的变化规律。Figure 2: The total shielding effectiveness, reflective shielding effectiveness and absorption shielding effectiveness of three-phase composite materials vary with the volume ratio of nickel/(nickel+ferrite).
具体实施方式 Detailed ways
本发明的目的是提供一种新型的电磁屏蔽复合材料及其制备方法。以Ba3Co2Fe23O41-Ni-PVDF，Ba3Co2Fe24O41-Ni-PVDF，Ba2Co2Fe11.5O22-Ni-PVDF，和Ba2Co2Fe12O22-Ni-PVDF四种三相复合体系作为实验对象。先按照配方将三种粉体混合均匀后，在低温下热压成型。The purpose of the present invention is to provide a novel electromagnetic shielding composite material and its preparation method. Take Ba 3 Co 2 Fe 23 O 41 -Ni-PVDF, Ba 3 Co 2 Fe 24 O 41 -Ni-PVDF, Ba 2 Co 2 Fe 11.5 O 22 -Ni-PVDF, and Ba 2 Co 2 Fe 12 O 22 - Ni-PVDF four three-phase composite system as the experimental object. First mix the three powders evenly according to the formula, and then hot press at low temperature.
本发明实施的工艺流程如下：The technological process that the present invention implements is as follows:
1)体积配料：按上述体积配方取2～3μm的镍粉7.5～45％，10～30μm的六角铁氧体粉5～42.5％，聚偏氟乙烯50％。1) Volume ingredients: 7.5-45% of nickel powder of 2-3 μm, 5-42.5% of hexagonal ferrite powder of 10-30 μm, and 50% of polyvinylidene fluoride according to the above-mentioned volume formula.
2)配样：将镍粉、聚偏氟乙烯以及铁氧体粉按照上述比例搅拌，混合均匀。2) Sample preparation: Stir nickel powder, polyvinylidene fluoride and ferrite powder according to the above ratio, and mix evenly.
3)成型：将混合均匀的粉末放在粉末压片机上，在温度为180～220℃，压力为10～15MPa的条件下，热压15～20min成型。3) Molding: put the uniformly mixed powder on a powder tablet press, and heat-press for 15-20 minutes under the conditions of temperature 180-220° C. and pressure 10-15 MPa.
以下例举实施例对本发明予以进一步说明。The following examples are given to further illustrate the present invention.
实施例1Example 1
按照表一中所列配方称取适量镍粉、Y型六角铁氧体与0.416g聚偏氟乙烯混合均匀后置于模具内，于200℃，15MPa下热压15min成型，可以得到一系列样品。According to the formula listed in Table 1, weigh an appropriate amount of nickel powder, Y-shaped hexagonal ferrite and 0.416g of polyvinylidene fluoride, mix them evenly, place them in the mold, and press them at 200°C and 15MPa for 15 minutes to form a series of samples. .
表一 实施例1成分配方Table 1 Embodiment 1 ingredient formula
说明：每一种复合材料中均含有50vol％PVDF，重量为0.416gDescription: Each composite material contains 50vol% PVDF and weighs 0.416g
实施例2Example 2
按照表二中所列配方称取适量镍粉、Y型六角铁氧体与0.416g聚偏氟乙烯混合均匀后置于模具内，于200℃，15MPa下热压15min成型，可以得到一系列样品。According to the formula listed in Table 2, weigh an appropriate amount of nickel powder, Y-shaped hexagonal ferrite and 0.416g polyvinylidene fluoride, mix them evenly, place them in the mold, and press them at 200°C and 15MPa for 15 minutes to form a series of samples. .
表二 实施例2成分配方Table two embodiment 2 ingredient formula
说明：每一种复合材料中均含有50vol％PVDF，重量为0.416g。Description: Each composite contains 50vol% PVDF and weighs 0.416g.
实施例3Example 3
按照表三中所列配方称取适量镍粉、Z型六角铁氧体与0.416g聚偏氟乙烯混合均匀后置于模具内，于200℃，15MPa下热压15min成型，可以得到一系列样品。According to the formula listed in Table 3, weigh an appropriate amount of nickel powder, Z-type hexagonal ferrite and 0.416g of polyvinylidene fluoride, mix them evenly, put them in the mold, and press them at 200°C and 15MPa for 15min to form a series of samples. .
表三 实施例3成分配方Table three embodiment 3 ingredient formula
说明：每一种复合材料中均含有50vol％PVDF，重量为0.416g。Description: Each composite contains 50vol% PVDF and weighs 0.416g.
实施例4Example 4
按照表四中所列配方称取适量镍粉、Z型六角铁氧体与0.416g聚偏氟乙烯混合均匀后置于模具内，于200℃，15MPa下热压15min成型，可以得到一系列样品。According to the formula listed in Table 4, weigh an appropriate amount of nickel powder, Z-type hexagonal ferrite and 0.416g of polyvinylidene fluoride, mix them evenly, place them in the mold, and press them at 200°C and 15MPa for 15 minutes to form a series of samples. .
表四 实施例4成分配方Table four embodiment 4 ingredient formula
说明：每一种复合材料中均含有50vol％PVDF，重量为0.416g。Description: Each composite contains 50vol% PVDF and weighs 0.416g.
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| CN101807744A (en) * | 2010-03-26 | 2010-08-18 | 西南交通大学 | Planar inverted-F antenna based on Z-type hexaferrite |
| CN105062417B (en) * | 2015-07-15 | 2017-07-21 | 北京新怡源环保科技有限公司 | A kind of organo-mineral complexing nanometer microwave absorbing material and preparation method thereof |
| CN106633547B (en) * | 2016-12-15 | 2018-11-27 | 陕西科技大学 | A kind of Z- type ferrite flaky powder/PVDF Wave suction composite material and preparation method thereof |
| CN107835628A (en) * | 2017-11-17 | 2018-03-23 | 桂林电子科技大学 | A kind of Fe/Y ferrites composite wave-suction material and preparation method thereof |
| CN110570977B (en) * | 2019-09-30 | 2021-08-10 | 江苏亨通线缆科技有限公司 | High electromagnetic shielding heat-resistant cable |
| CN110660502B (en) * | 2019-09-30 | 2021-06-04 | 江苏亨通线缆科技有限公司 | High-strength electromagnetic shielding cable |
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