阅读说明：本技术 电磁屏蔽填料、电磁屏蔽塑料 (Electromagnetic shielding filler and electromagnetic shielding plastic ) 是由 袁峰 于 2020-08-18 设计创作，主要内容包括：本发明公开了一种电磁屏蔽填料、电磁屏蔽塑料,其中电磁屏蔽填料由以下方法制备而成：将纳米金属氧化物加入到乙醇水溶液中超声处理,再添加氨水溶液继续超声；最后加入正硅酸乙酯反应,过滤,干燥。电磁屏蔽塑料包括以下重量份的原料：PVC树脂70-90份,PP树脂10-30份,上述电磁屏蔽填料10-20份,3-(2,3-环氧丙氧)丙基三甲氧基硅烷0.5-1份,双酚A-双(二苯基磷酸酯)0.5-1份,抗氧剂0.5-1份。本发明的电磁屏蔽塑料具有良好的电磁屏蔽性能。(The invention discloses an electromagnetic shielding filler and electromagnetic shielding plastic, wherein the electromagnetic shielding filler is prepared by the following method: adding the nano metal oxide into an ethanol water solution for ultrasonic treatment, and then adding an ammonia water solution for continuous ultrasonic treatment; finally adding tetraethoxysilane for reaction, filtering and drying. The electromagnetic shielding plastic comprises the following raw materials in parts by weight: 70-90 parts of PVC resin, 10-30 parts of PP resin, 10-20 parts of the electromagnetic shielding filler, 0.5-1 part of 3- (2, 3-epoxypropoxy) propyl trimethoxy silane, 0.5-1 part of bisphenol A-bis (diphenyl phosphate) and 0.5-1 part of antioxidant. The electromagnetic shielding plastic has good electromagnetic shielding performance.)

1. The electromagnetic shielding filler is characterized by being prepared by the following method: adding the nano metal oxide into an ethanol water solution for ultrasonic treatment, and then adding an ammonia water solution for continuous ultrasonic treatment; finally adding tetraethoxysilane for reaction, filtering and drying.

2. The electromagnetic shielding filler according to claim 1, prepared by the method comprising: adding nano metal oxide into 10-50 wt% ethanol water solution, wherein the mass ratio of the nano metal oxide to the 10-50 wt% ethanol water solution is (0.5-5):50, and performing ultrasonic treatment for 5-20 min; then, 18 wt% -25 wt% of ammonia water solution is dripped, the mass ratio of the 18 wt% -25 wt% of ammonia water solution to 10 wt% -50 wt% of ethanol water solution is (1-2):50, and the ultrasonic treatment is carried out for 20-60 min; dropwise adding tetraethoxysilane into the mixed solution, wherein the mass ratio of the tetraethoxysilane to the 10 wt% -50 wt% ethanol water solution is (0.1-1):50, and the stirring is carried out at the rotating speed of 300-; finally, centrifuging, filtering, washing with ethanol for 1-3 times, and oven drying at 50-100 deg.C.

3. The electromagnetic shielding filler of claim 2, wherein the nano metal oxide is at least one of nano nickel oxide, nano iron sesquioxide, and nano copper oxide.

4. The electromagnetic shielding plastic is characterized by comprising the following raw materials in parts by weight: 70-90 parts of PVC resin, 10-30 parts of PP resin, 10-20 parts of electromagnetic shielding filler according to claim 2, 0.5-1 part of 3- (2, 3-epoxypropoxy) propyl trimethoxy silane, 0.5-1 part of bisphenol A-bis (diphenyl phosphate) and 0.5-1 part of antioxidant.

5. The electromagnetically shielding plastic as claimed in claim 4, wherein: the antioxidant is N-cyclohexyl-N' -phenyl p-phenylenediamine and/or an antioxidant 1076.

6. The electro-magnetic shielding plastic of claim 4, wherein the preparation method of the electro-magnetic shielding plastic comprises the following steps: according to the formula, PVC resin, PP resin, the electromagnetic shielding filler, 3- (2, 3-epoxypropoxy) propyl trimethoxy silane, bisphenol A-bis (diphenyl phosphate) and an antioxidant are uniformly mixed, extruded, granulated and injection molded.

Technical Field

The invention relates to the technical field of plastics, in particular to an electromagnetic shielding filler and electromagnetic shielding plastic.

Background

With the wide application of computer networks, information processing devices, electronic communication devices, and the like in various industries, electromagnetic waves playing a key role in the computer networks, the information processing devices, the electronic communication devices, and the like are becoming more and more intimate with our lives. Electromagnetic radiation is the phenomenon that the electric field energy and magnetic field energy of electromagnetic waves are separated from a field source, spread to a far distance and do not return to the field source. The radiation of electromagnetic waves realizes the wireless, high-speed and remote information transmission, and promotes information communication; meanwhile, electromagnetic radiation also brings about a lot of negative effects, including electromagnetic interference, electromagnetic pollution, electromagnetic leakage and the like. When electromagnetic waves act on organisms, thermal effects, non-thermal effects and cumulative effects are generated by absorbing radiant energy. When the radiation energy exceeds a certain range, the electromagnetic wave may induce cancer, endocrine system disorders, visual impairment, immunodeficiency diseases, and the like.

Electromagnetic shielding technology is one of the main means for suppressing electromagnetic wave radiation, and effectively prevents electromagnetic waves from propagating from one side of a space to the other by blocking or reducing electromagnetic energy transmission. The metal fiber or metal sheet filled composite plastic has excellent conductivity, high shielding efficiency and good comprehensive performance, is a common electromagnetic shielding material, but has high processing cost and difficult fiber mixing, and the metal fiber or metal sheet is extremely easy to oxidize and corrode to influence the performance of the material. Therefore, it is of great significance to develop an electromagnetic shielding filler and corresponding electromagnetic shielding plastic for replacing metal.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, one of the technical problems to be solved by the present invention is: providing an electromagnetic shielding filler; the second technical problem to be solved by the invention is as follows: an electromagnetic shielding plastic is provided.

In order to achieve the purpose, the invention adopts the technical scheme that:

an electromagnetic shielding filler is prepared by the following method: adding the nano metal oxide into an ethanol water solution for ultrasonic treatment, and then adding an ammonia water solution for continuous ultrasonic treatment; finally adding tetraethoxysilane for reaction, filtering and drying.

Preferably, the electromagnetic shielding filler is prepared by the following method: adding nano metal oxide into 10-50 wt% ethanol water solution, wherein the mass ratio of the nano metal oxide to the 10-50 wt% ethanol water solution is (0.5-5):50, and performing ultrasonic treatment for 5-20 min; then, 18 wt% -25 wt% of ammonia water solution is dripped, the mass ratio of the 18 wt% -25 wt% of ammonia water solution to 10 wt% -50 wt% of ethanol water solution is (1-2):50, and the ultrasonic treatment is carried out for 20-60 min; dropwise adding tetraethoxysilane into the mixed solution, wherein the mass ratio of the tetraethoxysilane to the 10 wt% -50 wt% ethanol water solution is (0.1-1):50, and the stirring is carried out at the rotating speed of 300-; finally, centrifuging, filtering, washing with ethanol for 1-3 times, and oven drying at 50-100 deg.C to obtain; the ultrasonic frequency is 20kHz-25kHz, and the output power is 500W-800W.

Preferably, the nano metal oxide is at least one of nano nickel oxide, nano ferric oxide and nano copper oxide. The nano metal oxide is a mixture of nano nickel oxide and nano ferric oxide according to the mass ratio of (1-3) to 1.

According to the invention, the nano metal oxide is coated by the silicon dioxide, so that the electromagnetic shielding filler is uniformly dispersed in the plastic, on one hand, the effective surface area is increased, the dielectric property and the ferroelectric property of the plastic are enhanced, and the absorption loss of electromagnetic radiation is greatly increased; on the other hand, the coated silica shell serves as an interface, so that electromagnetic radiation is reflected and scattered on the interface for multiple times, and the loss of the electromagnetic radiation is further increased. In addition, when the nano metal oxide in the silicon-coated metal oxide nano material is selected from nano nickel oxide, the ultraviolet resistance of the plastic is enhanced, and unexpected technical effects are achieved. Furthermore, the nano nickel oxide and the nano ferric oxide are compounded to be used as the nano metal oxide, so that the synergy is realized, the electromagnetic shielding performance and the ultraviolet resistance are improved, and the comprehensive effect of 1+1 & gt 2 is obtained.

The invention also provides electromagnetic shielding plastic which comprises the following raw materials in parts by weight: 70-90 parts of PVC resin, 10-30 parts of PP resin, 10-20 parts of the electromagnetic shielding filler, 0.5-1 part of 3- (2, 3-epoxypropoxy) propyl trimethoxy silane, 0.5-1 part of bisphenol A-bis (diphenyl phosphate) and 0.5-1 part of antioxidant.

Preferably, the antioxidant is N-cyclohexyl-N' -phenyl-p-phenylenediamine and/or antioxidant 1076; further preferably, the antioxidant is N-cyclohexyl-N' -phenyl-p-phenylenediamine and the antioxidant 1076 in a mass ratio of 3: (1-3).

Preferably, the preparation method of the electromagnetic shielding plastic comprises the following steps: uniformly mixing PVC resin, PP resin, the electromagnetic shielding filler, 3- (2, 3-epoxypropoxy) propyl trimethoxy silane, bisphenol A-bis (diphenyl phosphate) and an antioxidant according to a formula, extruding, granulating and injection molding; the specific process parameters of the extrusion equipment are as follows: the temperature of the first zone is 285-290 ℃, the temperature of the second zone is 290-300 ℃, the temperature of the third zone is 300-310 ℃, the temperature of the fourth zone is 310-315 ℃, the temperature of the fifth zone is 290-300 ℃, and the rotating speed of the screw is 450-600 r/min.

The invention has the beneficial effects that: the electromagnetic shielding plastic has good electromagnetic shielding performance and ultraviolet resistance, is simple and convenient in preparation method and high in production efficiency, and is beneficial to general popularization and application. The silicon-coated metal oxide nano material is adopted, so that the effective surface area of the electromagnetic shielding filler is increased, and meanwhile, the coated silicon dioxide shell is used as an interface, so that electromagnetic radiation is reflected and scattered on the interfaces for many times, and the electromagnetic shielding efficiency of the electromagnetic shielding plastic is improved. In addition, when the nano metal oxide in the silicon-coated metal oxide nano material is selected from nano nickel oxide, the ultraviolet resistance of the electromagnetic shielding plastic is enhanced, and unexpected technical effects are achieved. Furthermore, the nano nickel oxide and the nano ferric oxide are compounded to be used as the nano metal oxide, so that the synergy is realized, and the electromagnetic shielding performance and the ultraviolet resistance are improved.

Detailed Description