Reconfigurable Microscale Frameworks from Concatenated Helices with Controlled Chirality

Abstract

The utility of helical structures in driving motion of microorganisms and plants has inspired efforts to develop synthetic stimuli‐responsive helical architectures for self‐motile and shape‐morphing systems. While several approaches to responsive helices based on hydrogels and liquid crystalline polymers have been reported, they have so far been limited to macroscopic (cm scale) dimensions, and have not been applied to concatenated helices with more than two segments. Here, a robust method for microfabrication of helices inspired by Bauhinia seedpods, based on trilayer samples consisting of rigid plastic stripes sandwiching a swellable temperature‐responsive hydrogel, is reported and the formation of responsive shape‐controlled frameworks from concatenated multiple helices (multihelices) with controlled chirality is demonstrated. The block angle at each helical junction is controlled by the change in stripe direction, while the torsion angle defined by each segment of three helices is prescribed by the net twist of the middle segment, providing simple geometric design rules for the fabrication of complex 3D structures. This work opens new directions in programming 3D shapes by providing new insight into helical segments as building blocks, with potential applicability to the fabrication of scaffolds for cell culture, reconfigurable microfluidic channels, and microswimmers.

Document Details

Document Type
Pub Defense Publication
Publication Date
Feb 21, 2017
Source ID
10.1002/adma.201606111

Entities

People

  • Ryan C Hayward
  • Seog‐Jin Jeon

Organizations

  • Army Research Office
  • Division of Civil, Mechanical & Manufacturing Innovation
  • University of Massachusetts Amherst

Tags

Readers

  • Nanocomposite Materials Science
  • Nanofabrication and Microfabrication.
  • Phased Array Antenna Design.