title: Self-organization of a mesoscale bristle into ordered, hierarchical helical assemblies.
abstract: Mesoscale hierarchical helical structures with diverse functions are abundant in nature. Here we show how spontaneous helicity can be induced in a synthetic polymeric nanobristle assembling in an evaporating liquid. We use a simple theoretical model to characterize the geometry, stiffness, and surface properties of the pillars that favor the adhesive self-organization of bundles with pillars wound around each other. The process can be controlled to yield highly ordered helical clusters with a unique structural hierarchy that arises from the sequential assembly of self-similar coiled building blocks over multiple length scales. We demonstrate their function in the context of self-assembly into previously unseen structures with uniform, periodic patterns and controlled handedness and as an efficient particle-trapping and adhesive system.
authors.affiliation: School of Engineering and Applied Sciences, Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA 02138, USA.
authors.forename: Boaz
authors.initials: B
authors.lastname: Pokroy
authors.forename: Sung H
authors.initials: SH
authors.lastname: Kang
authors.forename: L
authors.initials: L
authors.lastname: Mahadevan
authors.forename: Joanna
authors.initials: J
authors.lastname: Aizenberg