Liu Hongbo, Huang Jiajie, Guo Bingzhi
School of Materials and Environment, Beijing Institute of Technology, Zhuhai 519088, China.
Materials (Basel). 2023 Jul 5;16(13):4831. doi: 10.3390/ma16134831.
Dopamine was used to modify polytetrafluoroethylene (PTFE) in order to obtain functional polydopamine (PDA) surface-modified PTFE microporous film (PTFE@PDA). Ag was deposited on the surface of PTFE@PDA using electroless plating in order to obtain Ag-wrapped PTFE@PDA film (PTFE@Ag). A liquid-phase chemical reduction method was employed to prepare nickel nanochains. A Ni@PVDF cast film was obtained by mechanically blended nickel nanochains and polyimide (PVDF). The above two films were hot pressed to give a flexible, ultra-thin, and highly effective electromagnetic shielding composite film with a "3+2" layered structure. IR, XRD, and TEM results showed the PTFE@PDA film surface was coated by a tight plating layer of Ag particles with a particle size of 100~200 nm. PTFE@Ag+Ni@PVDF composite film exhibited excellent electromagnetic shielding effectiveness, with the conductivity of 7507.5 S/cm and the shielding effectiveness of 69.03 dB in the X-band range. After a 2000-cycle bending, this value still remained at 51.90 dB. Furthermore, the composite film presented excellent tensile strength of 62.1 MPa. It has great potential for applications in flexible and wearable intelligent devices.
使用多巴胺对聚四氟乙烯（PTFE）进行改性，以获得功能化聚多巴胺（PDA）表面改性的PTFE微孔膜（PTFE@PDA）。采用化学镀法在PTFE@PDA表面沉积Ag，以获得Ag包覆的PTFE@PDA膜（PTFE@Ag）。采用液相化学还原法制备镍纳米链。通过将镍纳米链与聚偏氟乙烯（PVDF）机械共混得到Ni@PVDF流延膜。将上述两种膜进行热压，得到具有“3+2”层状结构的柔性、超薄且高效的电磁屏蔽复合膜。红外光谱（IR）、X射线衍射（XRD）和透射电子显微镜（TEM）结果表明，PTFE@PDA膜表面被粒径为100~200 nm的Ag颗粒紧密镀层包覆。PTFE@Ag+Ni@PVDF复合膜表现出优异的电磁屏蔽效能，在X波段范围内电导率为7507.5 S/cm，屏蔽效能为69.03 dB。经过2000次循环弯曲后，该值仍保持在51.90 dB。此外，复合膜具有62.1 MPa的优异拉伸强度。它在柔性和可穿戴智能设备中具有巨大的应用潜力。
