title: Creating Honeycomb Structures in Porous Polymers by Osmotic Transport.
abstract: Understanding why honeycombs are shaped the way they are has moved biologists, physicists, chemists, and mathematicians alike. It was only recently that the honeycombs' shape "at birth" was included in the ongoing discussions: at birth, the cells are spherical but then transform into the well-known hexagons. It was proposed that a flow of wax-driven by surface tension effects-is the reason for this transformation. Our recent work on synthetic polymer foams with honeycomb-like structures points towards a very different mechanism. Just like in honeycomb cells, we observe that a spherical "initial state" transforms into a hexagon-shaped "final state" during polymerization. We have experimental evidence that a concentration gradient arises during polymerization, which transports monomers such that the spherical template becomes a honeycomb structure with walls of homogeneous thickness. The knowledge about this mechanism suggests promising strategies for the development of lightweight materials with optimized mechanical properties.
authors.affiliation: Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany.
authors.forename: Aggeliki
authors.initials: A
authors.lastname: Quell
authors.affiliation: Institute of Fluid Mechanics, Technische Universität Dresden, 01069, Dresden, Germany.
authors.forename: Sascha
authors.initials: S
authors.lastname: Heitkam
authors.affiliation: Laboratoire de Physique des Solides, CNRS, Université Paris-Sud, 91405, Orsay, France.
authors.forename: Wiebke
authors.initials: W
authors.lastname: Drenckhan
authors.affiliation: Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany.
authors.forename: Cosima
authors.initials: C
authors.lastname: Stubenrauch
mesh_terms: D015394:Molecular Structure; D009997:Osmotic Pressure; D010316:Particle Size; D058105:Polymerization; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry*; D016062:Porosity; D013499:Surface Properties
chemical_list: D011108:Polymers
keywords: bulk-phase initiation; honeycombs; interface initiation; osmotic transport; porous polymers