4D Printed Actuators with Soft-Robotic Functions.

Soft matter elements undergoing programed, reversible shape change can contribute to fundamental advance in areas such as optics, medicine, microfluidics, and robotics. Crosslinked liquid crystalline polymers have demonstrated huge potential to implement soft responsive elements; however, the complexity and size of the actuators are limited by the current dominant thin-film geometry processing toolbox. Using 3D printing, stimuli-responsive liquid crystalline elastomeric structures are created here.

Sub-5 nm Patterning by Directed Self-Assembly of Oligo(Dimethylsiloxane) Liquid Crystal Thin Films.

Highly ordered nanopatterns are obtained at sub-5 nm periodicities by the graphoepitaxial directed self-assembly of monodisperse, oligo(dimethylsiloxane) liquid crystals. These hybrid organic/inorganic liquid crystals are of high interest for nanopatterning applications due to the combination of their ultrasmall feature sizes and their ability to be directed into highly ordered domains without additional annealing.

Patterns of diacetylene-containing peptide amphiphiles using polarization holography.

The polarization dependence of a diacetylene polymerization was studied. For this purpose, peptide amphiphile fibers with a diacetylene moiety, which could only polymerize in the direction of the fiber, were employed. If nonaligned samples were illuminated with polarized light, only the fibers parallel to the polarization direction of the light were polymerized.

Artificial cilia for active micro-fluidic mixing.

In lab-on-chip devices, on which complete (bio-)chemical analysis laboratories are miniaturized and integrated, it is essential to manipulate fluids in sub-millimetre channels and sub-microlitre chambers. A special challenge in these small micro-fluidic systems is to create good mixing flows, since it is almost impossible to generate turbulence. We propose an active micro-fluidic mixing concept inspired by nature, namely by micro-organisms that swim through a liquid by oscillating microscopic hairs, cilia, that cover their surface.