dr. Leonid Ionov : Soft microorigami: self-folding polymer films
|When:||Th 08-05-2014 11:00 - 12:00|
ABSTRACTNature offers an enormous arsenal of ideas for the design of novel materials with superior properties and interesting behaviors. In particular, self-assembly and self-organization, which are fundamental to structure formation in nature, attract significant interest as promising concepts for the design of intelligent materials. Self-folding stimuli-responsive polymer films are exemplary biomimetic materials and can be viewed as model systems for bioinspired actuation. Such films, on one hand, mimic movement mechanisms in certain plant organs and, on the other hand, are able to self-organize and form complex 3D structures. These self-folding films consist of two polymers layers with different properties. For such a bilayer to changes its curvature at least one of these polymers, the active one, must change its volume more than the other one in response to changes in the external environmental such as temperature, pH or light. Because of this non-equal expansion of polymers, these films are able to form tubes, capsules or more complex structures. Similar to origami, the self-folding polymeric films provide unique possibilities for the straightforward fabrication of highly complex 3D micro-structures with patterned inner and outer walls that cannot be achieved using other currently available technologies.