基于预连接镍链的高应变敏感度动态可调电磁干扰屏蔽弹性体  

High-strain-sensitive dynamically adjustable electromagnetic interference shielding elastomer with pre-linked nickel chains

作　　者：卞敬 周兴成 周翔 马林峰 朱先军 李建民 刘淑娟 赵强 Jing Bian;Xingcheng Zhou;Xiang Zhou;Linfeng Ma;Xianjun Zhu;Jianmin Li;Shujuan Liu;Qiang Zhao(College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology),National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology,Nanjing University of Posts and Telecommunications,Nanjing 210023,China;State Key Laboratory of Organic Electronics and Information Displays&Jiangsu Key Laboratory for Biosensors,Institute of Advanced Materials(IAM),Nanjing University of Posts&Telecommunications,Nanjing 210023,China)

机构地区：[1]College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology),National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology,Nanjing University of Posts and Telecommunications,Nanjing 210023,China [2]State Key Laboratory of Organic Electronics and Information Displays&Jiangsu Key Laboratory for Biosensors,Institute of Advanced Materials(IAM),Nanjing University of Posts&Telecommunications,Nanjing 210023,China

出　　处：《Science China Materials》2024年第2期629-641,共13页中国科学（材料科学）（英文版）

基　　金：supported by the National Natural Science Foundation of China(52105576,22105106,22005151,62288102);the Open Project Program of the State Key Laboratory of Digital Manufacturing Equipment and Technology(DMETKF2021010);the open research fund of the National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology(KFJJ20210201);the general project of Natural Science Research in Colleges and Universities of Jiangsu Province(21KJB460017);the Natural Science Foundation of Jiangsu Province of China(BK20210603);the Start-up Funding sponsored by Nanjing University of Posts and Telecommunications(NY221003,NY220124)。

摘　　要：具有动态可调电磁屏蔽性能的电磁干扰屏蔽材料备受关注,但其目前仍然存在制备复杂、厚度大、触发方式不便、调节范围窄等缺点.我们通过将尖刺镍微粒精确地分散到聚二甲基硅氧烷基体中形成预连接的链状结构,制备出了具有可开关电磁屏蔽性能的弹性体材料.弹性体在机械拉伸和释放过程中表现出连续和可逆的电磁干扰屏蔽性能.原始弹性体具有良好的阻抗匹配和低介电损耗,允许大部分电磁波通过.拉伸使预连接的短链彼此接触,在内部形成大量的微尺度导电网络,显著增强了电导损耗能力,实现了较强的电磁干扰屏蔽能力.此外,我们通过无线应变传感系统验证了智能电磁干扰屏蔽弹性体的应用潜力,证明了可穿戴智能电磁干扰屏蔽精确监测人体运动的可能性.Smart electromagnetic interference(EMI)shielding materials with dynamic adjustable shielding performances are attractive,which however still suffer from complicated preparation,large thickness,inconvenient trigger mode,and relatively narrow adjustment range.Here,the off/on switchable EMI shielding elastomers are developed via precisely dispersing the spiked Ni microparticles(diameter:2±3μm)into polydimethylsiloxane matrix.By the gentle stir under low speed(300 r min^(−1))for a short time(3 min),the Ni particles could form irregular clusters as short chains,which approach being linked together but still maintain tiny gaps(<3μm)among them,showing a unique pre-linked-chains arrangement.The original elastomers show good impedance matching and low dielectric loss,allowing most EM waves to pass through.The stretching force presses the short pre-linked Ni chains to form massive microscale conductive paths inside(enlarge~6 orders of the original conductivity at 20%strain),which significantly enhance the capability of conduction loss and therefore trigger strong EMI shielding ability.The elastomer exhibits continuously and reversibly variable EMI shielding performances(~35 dB for a 0.3 mm single film,~55 dB for the sandwich design)during mechanical stretching and releasing by 0±20%strain.In addition,the applicability of the smart EMI shielding elastomer is demonstrated by a wireless strain sensing system,which shows the possibility for the wearable smart EMI shielding to monitor human body motion precisely.

关 键 词：adjustable electromagnetic interference shielding conductive elastomer electromagnetic sensing negative piezoresistivity 

分 类 号：TB34[一般工业技术—材料科学与工程] TN03[电子电信—物理电子学]