Micellization of Sliding Polymer Surfactants

TL;DR

This paper explores how the sliding degree of freedom in polymer surfactants influences their self-assembly, revealing the existence of two micelle types with different sizes and symmetries, and their dependence on molecular parameters.

Contribution

It introduces the concept of sliding polymer surfactants and analyzes their unique micellization behavior, including the presence of two free energy minima.

Findings

Two micelle size regimes with symmetric and asymmetric arms.

Small micelles reduce kinetic barriers for rapid equilibrium formation.

Micelle properties depend on specific molecular parameters.

Abstract

Following up a recent paper on grafted sliding polymer layers (Macromolecules 2005, 38, 1434-1441), we investigated the influence of the sliding degree of freedom on the self-assembly of sliding polymeric surfactants that can be obtained by complexation of polymers with cyclodextrins. In contrast to the micelles of quenched block copolymer surfactants, the free energy of micelles of sliding surfactants can have two minima: the first corresponding to small micelles with symmetric arm lengths, and the second corresponding to large micelles with asymmetric arm lengths. The relative sizes and concentrations of small and large micelles in the solution depend on the molecular parameters of the system. The appearance of small micelles drastically reduces the kinetic barrier signifying the fast formation of equilibrium micelles.