LAUSR

The effects of incorporating two imidazolium-type ionic liquids (ILs), 1-vinyl-3-butylimidazolium bis(trifluoromethylsulfonyl)imide (IL-TFSI) and 1-vinyl-3-butylimidazolium chloride (IL-Cl), on the crystal forms and phase microstructures of poly(vinylidene fluoride-co-hexafluoropropylene), P(VDF-co-HFP), were investigated. No change in the crystal form was observed with the incorporation of IL-TFSI because of the selective interaction between the IL and HFP moieties of the P(VDF-co-HFP) molecular chains. In contrast, the incorporation of IL-Cl induces an α-to-β crystal form transition because of the interactions between IL-Cl and the VDF moieties. Furthermore, the incorporation of IL-TFSI led to distinct phase separation of P(VDF-co-HFP), whereas a homogeneous phase structure was maintained with the incorporation of IL-Cl. Element mapping images reveal that the specific interactions of IL-TFSI with the HFP moieties induce enrichment of the HFP moieties, which results in well-defined HFP/IL-TFSI nanodomain...