2020 Impact factor 1.890
Soft Matter and Biological Physics


Eur. Phys. J. E 4, 327-336

Early stages of phase separation from polydisperse polymer mixtures

N. Clarke

Department of Chemistry, University of Durham, Science Laboratories, South Road, Durham, DH1 3LE, UK

nigel.clarke@durham.ac.uk

(Received 29 June 2000 and Received in final form 20 November 2000)

Abstract
We study the early stages of phase separation in a mixture of a polydisperse and a monodisperse polymer within the Cahn-Hilliard framework. We model the polydisperse component using a finite, but arbitrarily large, number of components, and show that the number of components required for convergent behaviour to be achieved is computationally undemanding. We study the growth rate of fluctuations following a quench into the two-phase region of the phase diagram. The q-dependence of the growth rate is shown to be commensurate with the behaviour of a monodisperse-monodisperse mixture, with the major difference being an effective mobility that is dependent on the quench depth. We also study the deviation of the time dependence of the scattering function from single exponential behaviour.

PACS
64.75.+g - Solubility, segregation and mixing; phase separation.
61.41.+e - Polymers, elastomers, and plastics.


© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2001