Solution processable liquid metal nanodroplets by surface-initiated atom transfer radical polymerization
Solution processable liquid metal nanodroplets by surface-initiated atom transfer radical polymerization
复制标题
DOI：
10.1038/s41565-019-0454-6
复制
发表时间：
2019-05
影响因子：
38.3
通讯作者：
Jiajun Yan;M. Malakooti;Zhao Lu;Zongyu Wang;Navid Kazem;C. Pan;M. Bockstaller;C. Majidi;K. Matyj
中科院分区：
文献类型：
--
作者：
Jiajun Yan;M. Malakooti;Zhao Lu;Zongyu Wang;Navid Kazem;C. Pan;M. Bockstaller;C. Majidi;K. Matyj
铕镓铟（EGaIn）是室温下的液态金属合金。EGaIn微滴可以掺入弹性体中，以制造具有高热稳定性和导电性的高度可拉伸，机械坚固，柔软的多功能复合材料，适用于软机器人和自修复电子产品。然而，目前的制备方法依赖于机械混合，这可能导致不规则形状的微米大小的液滴和各向异性的性质分布。因此，用于稳定亚微米尺寸的EGaIn液滴和在聚合物基质和溶剂中的相容化的程序已经引起了显著的关注。在这里，我们报告的EGaIn纳米液滴稳定的聚合物配体封装的合成。我们使用表面引发的原子转移自由基聚合引发剂与聚（甲基丙烯酸甲酯）（PMMA），聚（丙烯酸正丁酯）（PBMA），聚（2-二甲氨基）乙基甲基丙烯酸酯）（PDMAEMA）和聚（丙烯酸正丁酯-嵌段-甲基丙烯酸甲酯）（PBA-b-PMMA）的EGaIn纳米液滴表面上的氧化物层共价官能化。这些纳米液滴在有机溶剂、水中或高达50重量%浓度的聚合物基质中是稳定的，从而能够直接溶液浇铸成柔性混合材料。液态金属可以通过酸处理从分散体中回收。纳米液滴显示出良好的机械、热和光学性能，并显著抑制结晶和熔融温度（从15 °C降至−80 °C）。
Eutectic gallium indium (EGaIn) is a liquid metal alloy at room temperature. EGaIn microdroplets can be incorporated into elastomers to fabricate highly stretchable, mechanically robust, soft multifunctional composites with high thermal stability and electrical conductivity, –that are suitable for applications in soft robotics and self-healing electronics, –. However, the current methods of preparation rely on mechanical mixing, which may lead to irregularly shaped micrometre-sized droplets and an anisotropic distribution of properties. Therefore, procedures for the stabilization of sub-micrometre-sized droplets of EGaIn and compatibilization in polymer matrices and solvents have attracted significant attention, , –. Here we report the synthesis of EGaIn nanodroplets stabilized by polymeric ligand encapsulation. We use a surface-initiated atom transfer radical polymerization initiator to covalently functionalize the oxide layer on the surface of the EGaIn nanodroplets with poly(methyl methacrylate) (PMMA), poly(n-butyl acrylate) (PBMA), poly(2-dimethylamino)ethyl methacrylate) (PDMAEMA) and poly(n-butyl acrylate-block-methyl methacrylate) (PBA-b-PMMA). These nanodroplets are stable in organic solvents, in water or in polymer matrices up to 50 wt% concentration, enabling direct solution-casting into flexible hybrid materials. The liquid metal can be recovered from dispersion by acid treatment. The nanodroplets show good mechanical, thermal and optical properties, with a remarkable suppression of crystallization and melting temperatures (down to −80 °C from 15 °C).