Self-assembly scenarios of block copolymer stars

Author(s): Christian Koch, Christos Likos, Athanassios Panagiotopoulos, Federica LoVerso
Abstract: We examine the self-organization scenarios of star-shaped AB-block copolymers, consisting of a solvophilic A-block and a solvophobic B-block, in which f such blocks are chemically anchored on a common centre on their A-parts, leaving the B-blocks exposed on their exterior. We employ a lattice model and we perform Grand Canonical Monte Carlo simulations for the case f = 6, varying thereby the percentage of attractive monomers as well as the concentration of stars. In agreement with previous studies on the low-functionality case f = 3 [F. Lo Verso, A.Z. Panagiotopoulos, and C.N. Likos, Phys. Rev. E 79, 010401(R) (2009)], we find that when the majority of monomers in the star are attractive, macrophase separation between two fluid phases at different concentrations of stars occurs below a system-dependent critical temperature. When the majority of monomers is repulsive, novel forms of self-organization arise, which include not only well-defined spherical micelles but also the coexistence of a multiply-connected percolating cluster with smaller micelles having a well-defined size. The morphological characteristics and the sizes of the ensuing aggregates are quantitatively analysed and a critical comparison with the case f = 3 and f = 10 is presented.
Organisation(s): Computational and Soft Matter Physics
External organisation(s): Princeton University, Johannes Gutenberg-Universität Mainz
Journal: Molecular Physics: an international journal in the field of chemical physics
Volume: 109
Pages: 3049-3060
No. of pages: 12
ISSN: 0026-8976
DOI: https://doi.org/10.1080/00268976.2011.627385
Publication date: 2011
Peer reviewed: Yes
Austrian Fields of Science 2012: 103023 Polymer physics, 103036 Theoretical physics, 103015 Condensed matter, 103029 Statistical physics
Portal url: https://ucrisportal.univie.ac.at/en/publications/04b6a58a-83f0-447b-ac84-48fe64c3b01c