[Composites Part A]Multifunctional sponges with flexible motion sensing and outstanding thermal insulation for superior electromagnetic interference shielding
作者：Chaobo Liang#, Yuxuan Liu#, Yifeng Ruan, Hua Qiu*, Ping Song, Jie Kong, Haobin Zhang and Junwei Gu*
关键字：electromagnetic interference shielding
论文来源：期刊
发表时间：2020年
Although electrically conductive polymer composites (ECPCs) are promising in the application of electromagnetic interference (EMI) shielding, how to endow the ECPCs multifunctionality is still a huge challenge. In this work, the novel polyurethane@polydopamine@silver nanoparticles (PU@PDA@Ag) sponges with excellent compressibility, flexible motion sensing, outstanding thermal insulation and superior EMI shielding properties were successfully fabricated by a facile bio-response method, which could be obtained by following two steps: (i) PDA was decorated on the surface of PU sponges by dopamine self-polymerization. (ii) Ag nanoparticles were in-situ grown on the surface of PU sponges by electroless plating. PU@PDA@Ag sponge had the maximum EMI shielding effectiveness (SE) of 84 dB, and the corresponding specific SE and absolute SE were 2625 dB cm3 g-1 and 5250 dB cm2 g-1, much higher than those of other shielding foams/sponges. Meanwhile, PU@PDA@Ag sponge possessed low thermal conductivity (52.72 mW/mK), excellent compression resilience and piezoresistive properties.
如何制造轻质、良好柔韧性、优异绝热和电磁干扰（EMI）屏蔽性能的导电聚合物复合材料（ECPCs）是一项巨大的挑战。本文中，我们通过简单的生物响应法制备了一种超轻、出色可压缩回弹、运动感知、优异绝热和EMI屏蔽性能的聚氨酯@聚多巴胺@银纳米粒子（PU@PDA@Ag）海绵，其可通过两步获得：(ⅰ) 多巴胺自聚装饰在PU海绵表面；(ⅱ) 利用PDA的活性位点，通过化学电镀使Ag纳米粒子原位生长在PU表面。PU@PDA@Ag海绵具有高达84 dB的EMI效能（SE）值，对应的比屏蔽效能（SSE）和绝对屏蔽效能（SSEt）分别为2631 dB cm3/g和5263 dB cm2/g，几乎优于所有报道的泡沫/海绵的SSE和SSEt。此外，PU@PDA@Ag海绵同时具有超低的密度（0.0226～0.0320 g/cm3）和导热系数（52.72～63.54 mW/mK），出色的压缩回弹性以及压阻特性。出色的综合性能使PU@PDA@Ag海绵有望应用在轻质、柔性EMI屏蔽领域，如柔性电子设备、智能传感器、航空航天工程以及军事防御系统。