Europhys. Lett.
Volume 73, Number 2, January 2006
Page(s) 204 - 210
Section Atomic and molecular physics
Published online 02 December 2005
Europhys. Lett., 73 (2), pp. 204-210 (2006)
DOI: 10.1209/epl/i2005-10372-y

Copolymer adsorption kinetics at a selective liquid-liquid interface: Scaling theory and computer experiment

A. Corsi1, A. Milchev1, 2, V. G. Rostiashvili1 and T. A. Vilgis1

1  Max-Planck-Institute for Polymer Research - Ackermannweg 10 55128 Mainz, Germany
2  Institute for Physical Chemistry, Bulgarian Academy of Sciences 1113 Sofia, Bulgaria

received 24 August 2005; accepted in final form 9 November 2005
published online 2 December 2005

We consider the adsorption kinetics of a regular block copolymer of total length N and block size M at a selective liquid-liquid interface in the limit of strong localization. We propose a simple analytic theory based on scaling considerations which describes the relaxation of the initial coil into a flat-shaped layer. The characteristic times for attaining equilibrium values of the gyration radius components perpendicular and parallel to the interface are predicted to scale with chain length N and block length M as $\tau_{\perp} \propto M^{1+2\nu}$ (here $\nu\approx 0.6$ is the Flory exponent) and as $\tau_{\parallel} \propto N^2$, although the initial characteristic time of coil flattening is expected to grow with block size as $\propto M$. Since typically $N\gg M$ for multiblock copolymers, our results suggest that the flattening dynamics proceeds faster perpendicular rather than parallel to the interface. We also demonstrate that these scaling predictions agree well with the results of extensive Monte Carlo simulations of the localization dynamics.

36.20.-r - Macromolecules and polymer molecules.
68.05.-n - Liquid-liquid interfaces.
07.05.Tp - Computer modeling and simulation.

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