Ms Anastasia Elias

Liquid crystalline polymers are often described as 'artificial muscles' which convert thermal, chemical, or electromagnetic stimuli into mechanical energy.   One type of liquid crystalline elastomer, for example, has been shown to contract to 1/3 of its original length when heated.  Most of the literature regarding these materials is focused on the properties of macroscopic samples, while surprisingly little work has been undertaken toward integrating the materials into chip-scale devices.  Here, we demonstrate that liquid crystalline polymers are useful materials for microactuators by investigating patterning techniques and examining the behaviour of the materials when confined to a substrate.   We demonstrate the fabrication of photopatterned material that deforms with strains considerably larger than typical microactuator materials.

2. What has motivated you to conduct this work? 

From the beginning, research in the area of microsystems has focused predominantly on silicon due to the fact that fabrication techniques could be easily borrowed from the semiconductor industry.  However, there are a plethora of responsive materials that are far better suited to many of the applications in which silicon is currently used, and liquid crystalline polymers are among these materials.  The work was motivated by a desire to develop new, economical, non-lithographic techniques to pattern liquid crystalline polymers at the microscale, and to determine how these processes influence the properties of the material itself. 

3. Where do you see this work developing in the future? 

We anticipate the emergence of exciting new techniques in microfabrication that can be used to cheaply and efficiently pattern responsive materials.  Ultimately, the materials will be fully integrated in MEMS devices, such as the emerging lab-on-a-chip applications.

4. Are there any particular challenges facing future research in this area? 

As for most microdevices the largest obstacle to using liquid crystalline polymers in microactuators is integration.  This includes developing fabrication processes that are compatible with existing equipment, as well as building systems that are easily and conveniently connected with the outside world.  We believe that the benefits of using responsive materials will continue to push this work forward.