September 2016

New paper on polymer-stablized liquid crystal shells in Advanced Materials

Congratulations to JungHyun and Benjamin for their new Adv. Mater. paper "Taming Liquid Crystal Self-Assembly: The Multifaceted Response of Nematic and Smectic Shells to Polymerization" on polymer-stabilization of nematic and smectic liquid crystal shells, and the sometimes unexpected consequences for the liquid crystal self-assembly. By polymerizing a small fraction of the reactive mesogen RM257 in shells of 8CB or its homologues, certain defect configurations can be locked in place, the exact result depending sensitively on the mixture composition and the temperature at which polymerization is carried out. Surprisingly, when polymerizing close to a phase boundary, a transition into the adjacent phase can be induced. The new phase can be more or less ordered, depending on the starting situation. The lifetime of the shells is dramatically enhanced, as is the temperature stability. By tuning the conditions, the self-assembled structure can be made fully permanent, being visible even upon heating to the isotropic phase of the non-polymerized component, or it can be retained in a latent state, allowing macroscopic loss of order on heating to the isotropic phase yet with a memory of the chosen defect configuration when cooling down. Apart from proposing explanations for the various observations we discuss possibilities to apply the polymer-stabilized shells, for instance in advanced materials generation or in sensing.

Here you can find the full paper (don't forget to check out the rich supporting information, including many spectactular movies), and here is a layman's abstract for the paper.