Conformation of a polymer chain dissolved in a critical fluid

(Received 11 June 1993, revised 29 July 1993, accepted 31 August 1993)

Abstract
The problem of a polymer chain immersed in a critical fluid, e.g. a mixture of low molecular weight solvent close to its critical point, is studied and reformulated in a field theoretic framework. The starting point is a path integral formulation of the polymer chain which interacts with the solvent molecules. If the critical solvent is approximated by a Gaussian model all classical results are recovered, i.e. the polymer chain collapses close to the critical point. These results become modified at the critical point where non-classical exponents determine the precise form of the fluctuation induced interaction potential between two monomers of the chain, and so its conformation.