Shape-changing materials


Actuators are materials and devices, which are able to change their shape in response to change of environmental conditions (pH, T, UV, humidity) and, thus, perform mechanical work on nano, micro and marcoscales. Actuators find very broad application in microfabrication, microelectronics, medicine, lab-on-chip systems, etc. Because of their complexity, development of actuators includes both material and engineering aspects. There are plenty of examples of actuators based on metals, metal oxides and organic materials such as shape memory metals and polymers, bimetal strings, hydrogels etc. Among huge variety of different actuator materials polymer-based ones are highly attractive due to a spectrum of different properties of polymers. The polymers can be soft (viscoelastic state) and hard (glassy state) depending on their chemical and physical structure that allows the design of soft actuators for handling of soft living tissues and hard actuators for handling of metals. There are many polymers sensitive to different stimuli that allows design of actuators, which can be controlled by temperature, pH, biosignals, light, humidity, etc. Many polymers are biocompatible and biodegradable that allows integration of polymeric actuators in living systems and their resorption there.

We aim at the  engineering of functional polymer thin films and fibers, which are able to reversibly fold and to form different 3D objects in response to change of environmental conditions. The primary goal is to use this approach for  encapsulation of cells, design of scaffolds for tissue engineering, design of smart textiles and other.

 

Selected publications

Stroganov, V.; Al-Hussein, M.; Sommer, J.U.; Janke, A.; Zakharchenko, S.; Ionov, L.* Reversible thermosensitive biodegradable polymeric actuators based on confined crystallization, Nano Letters 2015, 15 (3), 1786–1790. DOI: 10.1021/nl5045023

Stroganov, V.; Zakharchenko, S.; Sperling, E.; Meyer, A.K.; Schmidt, O.G; Ionov, L*. Biodegradable self-folding polymer films with controlled thermo-triggered folding, Advanced Functional Materials 2014, 24(27), 4357–4363. DOI: 10.1002/adfm.201400176

Ionov, L.* Biomimetic hydrogel-based actuating systems Advanced Functional Materials 2013, 23 (36), 4555–4570. (invited review) DOI: 10.1002/adfm.201203692