title: Polymer collapse in miscible good solvents is a generic phenomenon driven by preferential adsorption.
abstract: Water and alcohol, such as methanol or ethanol, are miscible and, individually, good solvents for poly(N-isopropylacrylamide) (PNIPAm), but this polymer precipitates in water-alcohol mixtures. The intriguing behaviour of solvent mixtures that cannot dissolve a given polymer or a given protein, while the same macromolecule dissolves well in each of the cosolvents, is called cononsolvency. It is a widespread phenomenon, relevant for many formulation steps in the physicochemical and pharmaceutical industry, that is usually explained by invoking specific chemical details of the mixtures: as such, it has so far eluded any generic explanation. Here, by using a combination of simulations and theory, we present a simple and universal treatment that requires only the preferential interaction of one of the cosolvents with the polymer. The results show striking quantitative agreement with experiments and chemically specific simulations, opening a new perspective towards an operational understanding of macromolecular solubility.
authors.affiliation: Max-Planck Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany.
authors.forename: Debashish
authors.initials: D
authors.lastname: Mukherji
authors.affiliation: 1] Max-Planck Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany [2] Institut Charles Sadron, Université de Strasbourg, CNRS, 23 rue du Loess, 67034 Strasbourg Cedex 2, France.
authors.forename: Carlos M
authors.initials: CM
authors.lastname: Marques
authors.affiliation: Max-Planck Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany.
authors.forename: Kurt
authors.initials: K
authors.lastname: Kremer