Designing Nanostructured Materials Using Lyotropic Liquid Crystal Systems

Abstract: Self-assembly of amphiphilic molecules in the presence of two solvents (oil/water) leads to the formation of lyotropic liquid crystals (LLCs) with the length scale in the range of 2-50 nm, also called mesophases.

In the first example, we show that LLCs can be used as template to produce mesoporous/mesostructured polymers. The key point in this soft templating method is to preserve the structure. Using amphiphilic block copolymers with slow dynamics and crosslinking the monomer (oil) phase to arrest the structure, we have preserved the mesostructure upon polymerization in LLC templates.

The polymerized LLCs are fabricated as nanofiltration and ultrafiltration membranes with nanometer-size isoporous structure. They exhibit both excellent fouling resistance and high permeance of water, vastly outperforming conventional membranes made through non-solvent induced phase separation (NIPS).

As the second example, we show that ionogels can be obtained from LLCs of ionic liquid and amphiphilic molecules with applications in gas separation and electrolytes for energy storage. In conclusion, the LLCs can be tailored to produce membranes for a wide range of applications in separation and electrochemical processes.

Bio: Reza Foudazi is an associate professor in the School of Sustainable Chemical, Biological and Materials Engineering (SCBME) at the University of Oklahoma. Foudazi is also co-founder of Filtravate, a membrane technology company for applications in the bioprocessing and biopharmaceutical industries.