Liu Siqi, Walton Mia, Tarakina Nadezda V, Akcora Pinar
Department of Chemical Engineering & Materials Science, Stevens Institute of Technology Hoboken, New Jersey 07030, United States.
Department of Colloid Chemistry, Max Planck Institute of Colloids and Interfaces Research Campus Golm, Potsdam 14476, Germany.
J Phys Chem B. 2020 Jun 11;124(23):4843-4850. doi: 10.1021/acs.jpcb.0c02813. Epub 2020 Jun 2.
Polymer-grafted nanoparticles stabilized in ionic liquid (IL)-solvent mixtures are investigated by using transmission electron microscopy, dynamic light scattering, and electrochemical impedance spectroscopy. The ionic conductivity of IL-solvent mixtures with the polymer-grafted nanoparticles is found to be higher than that of nanoparticles in the IL. These particles offer additional interactions between polymer and IL, which can mitigate solvation in ILs with solvents. Motivated by this, we present the conductivity data of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (HMIM-TFSI) with poly(methyl methacrylate) (PMMA)-grafted particles in good and bad solvents and further discuss how graft density influences the swelling of PMMA and solvation characteristics of HMIM-TFSI. We found that HMIM-TFSI-acetonitrile containing high grafting density particles has a higher conductivity than that of the HMIM-TFSI-methanol mixture with grafted particles. Thus, solubility of PMMA in acetonitrile and preferential interactions between PMMA-HMIM-TFSI are shown to govern the swelling, solvation, and conductive properties of IL with the polymer-grafted nanoparticles.
通过透射电子显微镜、动态光散射和电化学阻抗谱对稳定在离子液体（IL）-溶剂混合物中的聚合物接枝纳米颗粒进行了研究。发现含有聚合物接枝纳米颗粒的IL-溶剂混合物的离子电导率高于IL中纳米颗粒的离子电导率。这些颗粒在聚合物和IL之间提供了额外的相互作用，这可以减轻IL与溶剂之间的溶剂化作用。受此启发，我们给出了1-己基-3-甲基咪唑鎓双（三氟甲基磺酰）亚胺（HMIM-TFSI）与聚（甲基丙烯酸甲酯）（PMMA）接枝颗粒在良溶剂和不良溶剂中的电导率数据，并进一步讨论了接枝密度如何影响PMMA的溶胀以及HMIM-TFSI的溶剂化特性。我们发现，含有高接枝密度颗粒的HMIM-TFSI-乙腈的电导率高于含有接枝颗粒的HMIM-TFSI-甲醇混合物的电导率。因此，PMMA在乙腈中的溶解度以及PMMA-HMIM-TFSI之间的优先相互作用显示出对含有聚合物接枝纳米颗粒的IL的溶胀、溶剂化和导电性能的控制作用。
