MEW of Liquid Crystal Elastomer Scaffolds with Programmed Mechanical Response:
MEW – Melt Electro Writing – means the deposition of thin fibres by electrostatic forces, following exactly pre-programmed patterns. With GeSiM BioScaffold printers, the MEW printhead deposits Gcode based geometries in the same way a pneumatic extruder does.
Customers of the Spanish National Council of Research (CSIC) in Spain now publish experiments with MEW Liquid Crystal Elastomer (LCE) Scaffolds printed using the MEW module of the GeSiM BS3.2.[1] LCEs are smart materials that strongly change their shape as a response of an external stimulus, for example temperature. As a result, these stimuli-responsive materials are good candidates to prepare actuators for biomedical and soft robotic applications.
The presented work describes the digital positioning of uniform LCE fibers with diameters ranging from hundreds of nanometers to tens of micrometers, difficult to access with conventional extrusion-based printing techniques. The fibers stacked precisely on top of the previous one, shaping LCE patterns structures with up to 50 layers leading to sharp and clear high aspect-ratio walls.
The fill-ins (Fig. 1) where not limited to simple rectangular patterns, but sinusoidal and round complex geometries could be achieved as well. The LCE samples can be released from the substrate and they can change their shape in a controlled fashion when exposed to the appropriate stimulus, temperature in the studied case. The authors of this study succeeded in preparing fiber-based complex scaffolds with programmed and reversibly shape morphing (Fig. 2), with potential for miniaturized actuators and smart structures for biomedical applications.
Fig. 1: Sinusoidal patterns printed by the MEW module of the GeSiM BioScaffold Printer BS3.2
