title: Shear dependent viscosity of poly(ethylene oxide) in two protic ionic liquids.
abstract: Steady shear viscosity measurements have been performed on 100 kDa poly(ethylene oxide) (PEO) dissolved in the protic ionic liquids ethylammonium nitrate (EAN) and propylammonium nitrate (PAN) and in water. The zero shear viscosity in all three solvents increases with polymer concentration, falling into three concentration regimes corresponding to dilute, semi-dilute and network solutions. Huggins plots reveal three distinct solvent conditions: good (water), good-theta (EAN) and theta (PAN). However, differences in the transition concentrations, power law behaviour of the viscosities, and relaxation times arising from shear thinning in the two ILs can be directly related to the effects of solvent nanostructure.
authors.affiliation: Centre for Advanced Particle Processing and Transport, Newcastle Institute for Energy and Resources, The University of Newcastle, NSW 2308, Australia.
authors.forename: J A
authors.initials: JA
authors.lastname: Smith
authors.affiliation: Centre for Advanced Particle Processing and Transport, Newcastle Institute for Energy and Resources, The University of Newcastle, NSW 2308, Australia.
authors.forename: G B
authors.initials: GB
authors.lastname: Webber
authors.affiliation: School of Chemistry F11, The University of Sydney, NSW 2006, Australia.
authors.forename: G G
authors.initials: GG
authors.lastname: Warr
authors.affiliation: Department of Pharmaceutical Technology, Institute for Pharmaceutical Science, University of Graz, 8010 Graz, Austria.
authors.forename: A
authors.initials: A
authors.lastname: Zimmer
authors.affiliation: Centre for Advanced Particle Processing and Transport, Newcastle Institute for Energy and Resources, The University of Newcastle, NSW 2308, Australia. Electronic address: rob.atkin@newcastle.edu.au.
authors.forename: R
authors.initials: R
authors.lastname: Atkin
authors.affiliation: Centre for Advanced Particle Processing and Transport, Newcastle Institute for Energy and Resources, The University of Newcastle, NSW 2308, Australia; Department of Pharmaceutical Technology, Institute for Pharmaceutical Science, University of Graz, 8010 Graz, Austria.
authors.forename: O
authors.initials: O
authors.lastname: Werzer
mesh_terms: D052578:Ionic Liquids / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D014783:Viscosity
chemical_list: D052578:Ionic Liquids; D000644:Quaternary Ammonium Compounds; C421484:ethylammonium; D011092:Polyethylene Glycols
keywords: Ionic liquids; Nanostructure; Polymer