(531b) Designing PIM-1 Microfibers with Tunable Morphology and Porosity Via Controlling Solvent/Nonsolvent/Polymer Interactions

Polymers of Intrinsic Microporosity (PIMs) are a novel class of high free volume polymer due to highly rigid and contorted molecular structure. Compared with conventional microporous materials e.g. activated carbon or zeolite, these polymers exhibit analogous behavior in the application of gas adsorption, separation, heterogeneous catalysis and energy storage, but in addition, could be solution-processed into different convenient forms. Most research on PIMs has been exclusively focused on fundamental membrane properties, with only very few research on exploring their fiber form. In this research, fabrication of PIM-1 microfibers with tunable morphology and porosity is achieved. This method involves the dissolution of PIM-1 in cosolvent systems composed of a good solvent and two different nonsolvents, respectively. Preliminary results demonstrate fiber surface evolves from a smooth surface to a wrinkled or porous surface with the solvent changing from a single good solvent to two cosolvent systems. In addition, PIM-1 fibers electrospun from one of the cosolvent systems exhibit comparable surface area as its powder form. As the morphology has important consequences on fiber properties, we anticipate current method could help design PIM-1 microfibers with tailored functionality and open up more opportunities in different application fields.