Templating polymer networks with chiral liquid crystals

Surface anchoring and geometry of the boundary strongly influence the configuration of liquid crystals (LCs). These properties not only affect the LC molecules’ alignment near the surface but also include the topological property in the bulk. Instead of manipulating only the external surface, a useful internal ‘surface’ can be introduced by using polymerizable monomers as a host LC.

The pseudolayers of chiral LCs are a good testbed to understand the role of frustration. By refilling different types of chiral LCs with different helical pitches, we test the ability of the polymer network to retain its structure even after the LCs have been washed away. Thus, we obtain free-standing films of polymer network that can be characterized by scanning electron microscopy.

We observe that the polymers do not destroy the intrinsic defects of LC but help stabilize the deformations. The solid network preserves the details of the LC structure when the original LC is washed away. With this strategy, we can get a better understanding of chiral LCs behavior by investigating the frustration of the chiral layers.