Programmable Liquid Crystal Elastomers Prepared by Thiol-Ene Photopolymerization (Postprint)
Abstract
The spontaneous conversion of a flat film into a 3-D shape requires local programming of the mechanical response. Historically, the ability to locally program the mechanical response of high strain (>30 ) liquid crystalline elastomers (LCEs) has been limited to magnetic or mechanical alignment techniques, which limits spatial resolution. Recently, we reported on the preparation of LCEs capable of 55 strain with spatial control of the mechanical response at scales as small as 0.01 mm2. Here, we report a distinct formulation strategy to realize programmable stimulus-response in LCEs. Photopolymerization of thiolene/acrylate formulations yields materials that exhibit large reversible strain up to 150 . The photopolymerization reaction is extremely rapid, reducing preparation time from days to minutes. The mechanical behavior of these materials can be tuned by varying cross-link density. Spatial and hierarchical programming of the director profile is demonstrated, enabling 3-D shape change, including twisting ribbons and localized Gaussian curvature.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 17, 2015
- Accession Number
- AD1029210
Entities
People
- Claire M. Middleton
- Scott T Iacono
- Taylor H. Ware
- Timothy White
- Zachary P. Perry
Organizations
- Air Force Research Laboratory Materials and Manufacturing Directorate