Advanced Functional Materials, Vol.26, No.48, 9009-9016, 2016
Order at Extreme Dilution
Control over the organization of assemblies from molecular dimensions up to the macroscopic length scale is an outstanding challenge in science, above all for materials in high dilution. Instead of inducing order by generating very long and stiff structures, an alternative approach is studied: a two-component assembly of a semiflexible polymer with a (self-assembling) chromonic liquid crystal. By following the structure formation in time using different techniques, a mechanistic model is proposed that explains how such unusually well-defined materials can be created from flexible components. It is concluded that at this very low concentration (>99.6% water), these macroscopically organized structures can only be formed when the energies between different assembly states and their interconversion rates are properly balanced. This may, however, be in reach for a wide range of materials, which makes this a generic route toward high definition at low concentration without the need for long and rigid building blocks.
Keywords:chromonic liquid crystals;high dilution;macroscopic anisotropy;self-assembly;semiflexible polymers