Berlin 2015 – wissenschaftliches Programm
CPP 58.1: Hauptvortrag
Mittwoch, 18. März 2015, 15:45–16:15, PC 203
The Tricontinuous 3ths(5) Phase: A New Morphology in Copolymer Melts — •Gerd Schroeder-Turk1,2,3, Michael Fischer1,2,4, Liliana de Campo2,5, Jacob Kirkensgaard6, and Stephen Hyde2 — 1Theor. Physik, Fried.-Alex. Univ. Erlangen-Nürnberg, Germany — 2Applied Maths, Res. School of Physics & Eng., Australian National Univ., Canberra, Australia — 3School of Engineering & Inform. Technol., Murdoch Univ., Western Australia — 4Adolphe Merkle Institute, Fribourg, Switzerland — 5Australian National Science & Technol. Organisation, Bragg Institute, NSW, Australia — 6Niels Bohr Institute, Univ. of Copenhagen, Denmark
Self-assembly remains the most efficient route to the formation of ordered nanostructures, including the double gyroid network phase in diblock copolymers based on two intergrown network domains. Here we use self-consistent field theory to show that a tricontinuous structure with monoclinic symmetry, called 3ths(5), based on the intergrowth of three distorted ths nets, is an equilibrium phase of triblock star-copolymer melts when an extended molecular core is introduced. The introduction of the core enhances the role of chain stretching by enforcing larger structural length scales, thus destabilizing the hexagonal columnar phase in favor of morphologies with less packing frustration. This study further demonstrates that the introduction of molecular cores is a general concept for tuning the relative importance of entropic and enthalpic free energy contributions, hence providing a tool to stabilize an extended repertoire of nanostructured phases.
Reference: Fischer et al, Macromolecules 47, 7424-7430 (2014)