Controlling Liquid Crystal Configuration and Phase Using Multiple Molecular Triggers

Liquid crystals are able to transform a local molecular interaction into a macroscopic change of state, making them a valuable smart material. Here, we investigate a novel polymeric amphiphile as a candidate for molecular triggering of liquid crystal droplets in aqueous background. Using microscopy equipped with crossed polarizers and optical tweezers, we find that the monomeric amphiphile is able to trigger both a fast phase change and then a subsequent transition from nematic to isotropic. We next include sodium dodecyl sulfate (SDS), a standard surfactant, with the novel amphiphilic molecules to test phase transitioning when both were present. As seen previously, we find that the activity of SDS at the surface can result in configuration changes with hysteresis. We find that the presence of the polymeric amphiphile reverses the hysteresis previously observed during such transitions. This work demonstrates a variety of phase and configuration changes of liquid crystals that can be controlled by multiple exogenous chemical triggers.

Automated summary

This study demonstrates that a novel polymeric amphiphile can act as a molecular triggering agent for phase transitions of liquid crystal droplets in an aqueous background. The presence of sodium dodecyl sulfate reverses the hysteresis previously observed during the transitions. The phase and configuration changes of liquid crystals can be controlled by multiple exogenous chemical triggers.