The surface of hollow glass microspheres (HGMs) was roughened by a HCl+NH_(4)F strategy,which achieved a broken ratio as 16.10%,and then metallized by electroless plating by Co nanoparticles up to 90 wt% (abbreviated ...The surface of hollow glass microspheres (HGMs) was roughened by a HCl+NH_(4)F strategy,which achieved a broken ratio as 16.10%,and then metallized by electroless plating by Co nanoparticles up to 90 wt% (abbreviated as Co-HGMs).The average grain size of Co was measured to range from 0.4 to 0.5 μm.Then Co-HGMs were mixed with liquid silicone rubber and xylene,and cured on a perspex plate applicable for flexible electromagnetic shielding.By attentive parameter optimization,a film about 0.836 mm in thickness was obtained with a density of 0.729 g/cm^(3),showing a shielding effectiveness of 15.2 dB in the X-band (8.2-12.4 GHz) at room temperature,which was ascribed to the formation of a conductive network of Co-HGMs inside the film.Simultaneously,the tensile strength of 0.89 MPa at an elongation ratio of 194.5% was also obtained,showing good mechanical properties and tensile strength.展开更多
Flexible electromagnetic interference(EMI)shielding films with high stability have shown promising prospect in harsh working conditions such as military,communication,and special protection fields.Herein,flexible aram...Flexible electromagnetic interference(EMI)shielding films with high stability have shown promising prospect in harsh working conditions such as military,communication,and special protection fields.Herein,flexible aramid nanofibers@polypyrrole(ANF@PPy)films with high stability were easily achieved by the in-situ growth of PPy on the surface of ANF and the subsequent pressured-filtration film-forming process.When the amount of pyrrole(Py)monomer is 40μL,the ANF@PPy(AP40)film exhibited excellent EMI shielding performance with shielding effectiveness(SE)of 41.69 dB,tensile strength of 96.01 MPa,and fracture strain of 21.95%at the thickness of 75.76μm.Particularly,the anticipated EMI shielding performance can be maintained even after being heated at 200℃in air,soaked in 3.5%NaCl solution,repeated folding for one million times,or burned directly,indicating superior environmental durability in harsh conditions.Therefore,it is believed that the ANF@PPy films with high stability offer a facile solution for practical protection for high-performance EMI shielding applications.展开更多
A flexible electromagnetic interference(EMI)shielding film was innovatively fabricated using both low melting temperature solder arrays and amorphous soft magnet particulates consolidated on a polyethylene terephthala...A flexible electromagnetic interference(EMI)shielding film was innovatively fabricated using both low melting temperature solder arrays and amorphous soft magnet particulates consolidated on a polyethylene terephthalate(PET)substrate.First,the IneSneBi solder arrays presented a low melting point of 99.4C,which enabled attachment to the heat-sensitive plastic substrate without any thermal damage,and a low electrical resistivity of 14.1 mU cm,making them very effective at interrupting EM waves.Second,the solder arrays with a high thermal conductivity of 61.2 W/(m$K)at 298.15 K were also useful as a thermal conductor for a heat sink.Thus,the solder arrays provide efficient electrical and thermal channels for electron transport induced by abruptly or consistently created EM waves due to suddenly turning on and the long term operation of electronics,respectively.Third,the Fe-based magnetic particulates were added and resulted in effective saturation magnetization of 161.1 emu/g,remanence of 2.9 emu/g,and coercivity of 12.5 G,thus were able to disturb the EM pathway because of their soft magnetic properties.Consequently,the hybrid EMI shielding film with exceptionally high electrical and thermal conductivity and superior soft magnetic properties provided remarkable shielding effectiveness of 102.5 dB at 10.2 GHz.展开更多
文摘The surface of hollow glass microspheres (HGMs) was roughened by a HCl+NH_(4)F strategy,which achieved a broken ratio as 16.10%,and then metallized by electroless plating by Co nanoparticles up to 90 wt% (abbreviated as Co-HGMs).The average grain size of Co was measured to range from 0.4 to 0.5 μm.Then Co-HGMs were mixed with liquid silicone rubber and xylene,and cured on a perspex plate applicable for flexible electromagnetic shielding.By attentive parameter optimization,a film about 0.836 mm in thickness was obtained with a density of 0.729 g/cm^(3),showing a shielding effectiveness of 15.2 dB in the X-band (8.2-12.4 GHz) at room temperature,which was ascribed to the formation of a conductive network of Co-HGMs inside the film.Simultaneously,the tensile strength of 0.89 MPa at an elongation ratio of 194.5% was also obtained,showing good mechanical properties and tensile strength.
基金the Science and Technology Commission of Shanghai Municipality(Nos.20230742300 and 18595800700)the project of“joint assignment”in Shanghai University led by Prof.
文摘Flexible electromagnetic interference(EMI)shielding films with high stability have shown promising prospect in harsh working conditions such as military,communication,and special protection fields.Herein,flexible aramid nanofibers@polypyrrole(ANF@PPy)films with high stability were easily achieved by the in-situ growth of PPy on the surface of ANF and the subsequent pressured-filtration film-forming process.When the amount of pyrrole(Py)monomer is 40μL,the ANF@PPy(AP40)film exhibited excellent EMI shielding performance with shielding effectiveness(SE)of 41.69 dB,tensile strength of 96.01 MPa,and fracture strain of 21.95%at the thickness of 75.76μm.Particularly,the anticipated EMI shielding performance can be maintained even after being heated at 200℃in air,soaked in 3.5%NaCl solution,repeated folding for one million times,or burned directly,indicating superior environmental durability in harsh conditions.Therefore,it is believed that the ANF@PPy films with high stability offer a facile solution for practical protection for high-performance EMI shielding applications.
基金This study was partially sup-ported by the Korea Institute of Materials Science(KIMS).This work was mainly supported by the National Research Council of Science&Technology(NST)grant(No CRC-15-03-KIMM)of the Ministry of Science,ICTand Future Planning(MSIP)in the Korea government.This research was also supported by the Korea Institute of Industrial Technology(KTTECH)internal project(Grant No.P]A18350).
文摘A flexible electromagnetic interference(EMI)shielding film was innovatively fabricated using both low melting temperature solder arrays and amorphous soft magnet particulates consolidated on a polyethylene terephthalate(PET)substrate.First,the IneSneBi solder arrays presented a low melting point of 99.4C,which enabled attachment to the heat-sensitive plastic substrate without any thermal damage,and a low electrical resistivity of 14.1 mU cm,making them very effective at interrupting EM waves.Second,the solder arrays with a high thermal conductivity of 61.2 W/(m$K)at 298.15 K were also useful as a thermal conductor for a heat sink.Thus,the solder arrays provide efficient electrical and thermal channels for electron transport induced by abruptly or consistently created EM waves due to suddenly turning on and the long term operation of electronics,respectively.Third,the Fe-based magnetic particulates were added and resulted in effective saturation magnetization of 161.1 emu/g,remanence of 2.9 emu/g,and coercivity of 12.5 G,thus were able to disturb the EM pathway because of their soft magnetic properties.Consequently,the hybrid EMI shielding film with exceptionally high electrical and thermal conductivity and superior soft magnetic properties provided remarkable shielding effectiveness of 102.5 dB at 10.2 GHz.
