Soft Matter Invited Talk

Markus Müller (Georg-August-Universität)

Studying the kinetics of copolymer self-assembly 

Copolymers are flexible macromolecules that are comprised of two (or more) blocks. The incompatibility between the constituents of different blocks gives rise to microphase separation on the length scale of 5 -70 nm. Much effort has been devoted to utilizing these soft materials as templates for nanostructures, e.g., for integrated circuits and memory devices, and fabricating defect-free structures or structures that differ from the thermodynamically stable morphologies in the bulk.

Computational modeling can contribute to optimizing material parameters such film thickness, interaction between copolymer blocks and substrate, geometry of confinement, and it provides fundamental insights into the physical mechanisms of directing the self-assembly, addressing both the equilibrium structure and thermodynamics and the kinetics of self-assembly.

I will discuss highly coarse-grained particle-based models that allow us to access the long time and large length scales associated with self-assembly [1,2], review computational methods [2,3] to determine the free energy of self-assembled structures [4,5] and to investigate the kinetic pathways of structure formation [6]. Opportunities for directing the kinetics of self-assembly by temporal changes of thermodynamic conditions will be discussed.

[1] M. Müller, J. Stat. Phys. 145 (2011), 967
[2] M. Müller and J.J. de Pablo, Annual Rev. Mater. Res. 43 (2013), 1-34
[3] M. Müller and K.Ch. Daoulas, Phys. Rev. Lett. 107 (2011), 227801
[4] M. Müller, Phys. Rev. Lett. 109 (2012), 087801
[5] U. Nagpal, M Müller, P.F. Nealey, and J.J. de Pablo, ACS Macro Letters 1 (2012), 418 [6] M. Müller and D.W. Sun, Phys. Rev. Lett. 111 (2013), 267801