Mixtures of benzene and chloroform near a silica with grafted poly(ethylene oxide) chains

Abstract

The influence of mixtures of chloroform and benzene in different proportions on the conformations of poly(ethylene oxide) chains of molecular weight 2000 grafted on silica has been studied by the e.s.r. spectroscopy of labelled macromolecules. There is a displacement effect, in which the chains are more extended in solution at a given temperature, when the amount of CHCl₃ increases in the bulk solution. Moreover, with the grafting ratio used, no particular partitioning of the solvents inside the grafted layer is observed with this technique. Therefore the unfolding of the macromolecules in the liquids follows exactly the composition of the mixture.