Xu Fan, Chen Ruofan, Lin Zaishan, Qin Yuyang, Yuan Ye, Li Ying, Zhao Xu, Yang Minglong, Sun Xianxian, Wang Shasha, Peng Qingyu, Li Yibin, He Xiaodong
Center for Composite Materials and Structures, School of Astronautics, Harbin Institute of Technology, Harbin 150080, P. R. China.
Shenzhen STRONG Advanced Materials Research Institute Co., Ltd., Shenzhen 518000, P. R. China.
ACS Omega. 2018 Mar 30;3(3):3599-3607. doi: 10.1021/acsomega.8b00432. eCollection 2018 Mar 31.
Graphene-enhanced polymer matrix nanocomposites are attracting ever increasing attention in the electromagnetic (EM) interference (EMI) shielding field because of their improved electrical property. Normally, the graphene is introduced into the matrix by chemical functionalization strategy. Unfortunately, the electrical conductivity of the nanocomposite is weak because the graphene nanosheets are not interconnected. As a result, the electromagnetic interference shielding effectiveness of the nanocomposite is not as excellent as expected. Interconnected graphene network shows very good electrical conduction property, thus demonstrates excellent electromagnetic interference shielding effectiveness. However, its brittleness greatly limits its real application. Here, we propose to directly infiltrate flexible poly(dimethylsiloxane) (PDMS) into interconnected reduced graphene network and form nanocomposite. The nanocomposite is superflexible, light weight, enhanced mechanical and improved electrical conductive. The nanocomposite is so superflexible that it could be tied as spring-like sucker. Only 1.07 wt % graphene significantly increases the tensile strengths by 64% as compared to neat PDMS. When the graphene weight percent is 3.07 wt %, the nanocomposite has the more excellent electrical conductivity up to 103 S/m, thus more outstanding EMI shielding effectiveness of around 54 dB in the X-band are achieved, which means that 99.999% EM has been shielded by this nanocomposite. Bluetooth communication testing with and without our nanocomposite confirms that our flexible nanocomposite has very excellent shielding effect. This flexible nanocomposite is very promising in the application of wearable devices, as electromagnetic interference shielding shelter.
石墨烯增强聚合物基纳米复合材料因其电学性能的改善而在电磁干扰(EMI)屏蔽领域受到越来越多的关注。通常,通过化学功能化策略将石墨烯引入基体中。不幸的是,由于石墨烯纳米片未相互连接,纳米复合材料的电导率较弱。因此,纳米复合材料的电磁干扰屏蔽效能不如预期的优异。相互连接的石墨烯网络显示出非常好的导电性能,从而展现出优异的电磁干扰屏蔽效能。然而,其脆性极大地限制了其实际应用。在此,我们提出将柔性聚二甲基硅氧烷(PDMS)直接渗透到相互连接的还原石墨烯网络中,形成纳米复合材料。该纳米复合材料具有超柔性、重量轻、机械性能增强和导电性能改善等特点。这种纳米复合材料非常柔韧,以至于可以像弹簧一样被捆绑起来。与纯PDMS相比,仅1.07 wt%的石墨烯就能使拉伸强度显著提高64%。当石墨烯重量百分比为3.07 wt%时,纳米复合材料具有高达103 S/m的更优异电导率,从而在X波段实现了约54 dB的更出色电磁干扰屏蔽效能,这意味着该纳米复合材料屏蔽了99.999%的电磁干扰。在有和没有我们的纳米复合材料的情况下进行的蓝牙通信测试证实,我们的柔性纳米复合材料具有非常优异的屏蔽效果。这种柔性纳米复合材料作为电磁干扰屏蔽罩在可穿戴设备应用中非常有前景。