Silk Fibroin Bending Actuators as an Approach Toward Natural Polymer Based Active Materials
mediaposted on 06.08.2019 by Ander Reizabal, Daniela M. Correia, Carlos M. Costa, Leyre Perez-Alvarez, José L. Vilas-Vilela, S. Lanceros-Méndez
Media is any form of research output that is recorded and played. This is most commonly video, but can be audio or 3D representations.
This work reports on the development of ionic liquid (IL)/silk fibroin (SF) composite films as electroactive polymers actuators. Different contents (20, 40, and 60% wt) of 1-butyl-3-methylimidazolium tricyanomethanide ([Bmim][C(CN3)]) and choline dihydrogen phosphate ([Ch][DHP]) ILs were incorporated into the SF polymer matrix. Due to IL–SF interactions, morphological changes such as globule-like nanostructures are induced in the samples. High concentrations of IL promote SF β-sheet formation above 65%. Further, an increase in the thermal stability of the SF was observed through the incorporation of [Bmim][C(CN3)]. IL type and content allow tuning of the electrical response as well as achieving bending actuation. [Bmim][C(CN3)]/SF samples allow bending responses up to 0.5 at an applied voltage of 3 V. In conclusion, this work demonstrates the ability of IL/SF composites to act as electroactive polymer actuators and opens new perspectives in the application of natural resources for smart materials.