Polymer membranes for separation of small molecules and ions

Young Moo Lee
Department of Energy Engineering, Hanyang University, Seoul, Korea

Microporous polymers are a class of polymeric materials with high free volumes and large surface areas. Microporous polymers have received much attention for various energy-related applications in gas separation, gas storage, and for clean energy resources due to their easy processability as well as microporosity for high performance. As gas separation membrane materials, microporous materials exhibit high flux based on the fast gas transport through membrane matrix. Moreover, the easy processability of polymer materials has been a great advantage for expansion into industrial applications.

Reported rigid polymer membranes, so-called thermally rearranged (TR) polymer membranes have been developed from ortho-functionalized polyimides by a post thermal conversion process. They demonstrate bimodal cavity size of 0.3-0.4 nm and 0.7-0.9 nm and narrow cavity size distributions characterized by PALS measurement which is an efficient transport path for small molecules, especially for CO2 molecules. As a result, TR polymer membranes exhibit both high permeability and high selectivity based on high diffusion of gas molecules. TR polymer membranes are also suitable for water treatment applications due to their microporous characteristics. In this presentation, we will report on the recent progress of thermally rearranged microporous polymer membranes for applications such as in energy and water.

 In addition to microporous polymer membranes, polymer membranes with enhanced ion separation are very important to transport of ions for fuel cells and Li ion batteries and water hydrolysis. This presentation briefly introduces polymer membranes for separating ions.

 Keywords
thermally rearranged polymer; gas separation; PRO; battery