Macromolecules, Vol.50, No.17, 6631-6636, 2017
Unexpected Solvent Influence on the Rheology of Supramolecular Polymers
A very limited change in the nature of the solvent (toluene versus pentylbenzene) can have an unexpectedly strong effect on the viscosity of a hydrogen bonded supramolecular polymer. In pentylbenzene, slightly stronger hydrogen bonds are formed than in toluene, but the supramolecular polymer solution is ca. 25 times less viscous. Several hypotheses can be envisaged to explain this counter-intuitive result. We propose that this effect is actually related to a solvation effect involving the outer corona of the supramolecular objects. When the cohesive energy density of the solvent approaches the cohesive energy density of the outer corona of the supramolecular objects, the viscosity of solution is reduced, possibly because of faster local dynamics.