Chen Zhengfei, FitzGerald Paul A, Warr Gregory G, Atkin Rob
Newcastle Institute for Energy and Resources, The University of Newcastle, Callaghan, NSW, Australia.
Phys Chem Chem Phys. 2015 Jun 14;17(22):14872-8. doi: 10.1039/c5cp02033f.
The conformation of 38 kDa PEO in a solvate ionic liquid (SIL), lithium tetraglyme bis(trifluoromethane-sulfonyl)amide ([Li(G4)]TFSI) from dilute to concentrated solution regimes has been determined by small angle neutron scattering and rheology. SANS analysis reveals that [Li(G4)]TFSI is better than a theta solvent (theta-good) for PEO. The variation of the radius of gyration (Rg) and viscosity as a function of polymer concentration allow the overlap concentrations, c* and c**, to be identified at 13 mg mL(-1) and 50 mg mL(-1), respectively, which are similar to values reported previously for conventional ionic liquids. Unlike water and conventional ionic liquids, [Li(G4)]TFSI cannot form hydrogen bonds with PEO. Thermal gravimetric analysis indicates that the solvation of PEO by [Li(G4)]TFSI is a consequence of PEO forming coordinate bonds with the lithium by displacing the anion, but without displacing the glyme molecule.
通过小角中子散射和流变学方法，测定了38 kDa聚环氧乙烷（PEO）在溶剂化离子液体（SIL）四甘醇二甲醚锂双（三氟甲烷磺酰）亚胺（[Li(G4)]TFSI）中从稀溶液到浓溶液状态下的构象。小角中子散射分析表明，[Li(G4)]TFSI对PEO而言比θ溶剂（θ良溶剂）更好。回转半径（Rg）和粘度随聚合物浓度的变化使得能够分别在13 mg mL⁻¹和50 mg mL⁻¹处确定重叠浓度c和c*，这与先前报道的传统离子液体的值相似。与水和传统离子液体不同，[Li(G4)]TFSI不能与PEO形成氢键。热重分析表明，[Li(G4)]TFSI对PEO的溶剂化作用是PEO通过取代阴离子与锂形成配位键的结果，但并未取代甘醇二甲醚分子。
