Processing for Polymer Electronics

We are currently investigating greener preparation methods for conjugated polymer thin films used in flexible electronics applications. Most electroactive polymers have limited solubility in organic solvents; thus, aggresive and hazardous dissolution schemes must be used to produce inks suitable for roll-to-roll coating. Further, the polymer tends to crystallize out of solution leading to irreproducible coating quality. Our work seeks to replace the toxic solvents with suspensions in non-solvents, which has the added advantage of decoupling the polymer crystallization and the ink drying step.

Novel Renewable Polymer Blends

Bio-derived plastics suffer from inferior physical properties compared to their petroleum-derived counterparts, and in addition they can be difficult to process. Both of these limitations prevent their wider acceptance in the market. Polymer blends can access physical properties above and beyond those of the components. Current NSF funding (CMMI-1350445) supports our studies of the effects of high shear and interfacial reaction on polymer blends based on renewable resources. High-speed extrusion instrumentation newly available in the Plastics Engineering department facilitates this work on novel sustainable polymer blends.

Polymer and Nanocomposite Rheology

Because the interfacial area is so large in nanocomposites, the competing enthalpic and entropic effects of interfacial interactions can significantly affect polymer dynamics. The amount of shear work needed to disperse the particles is directly related to the chemical affinity between the polymer and filler. Our current NSF-funded project (EEC-1342229) utilizes important bio-based polymers and model nanoparticle surfaces that can easily be chemically altered to study confinement of the polymer near the particle surface.