High-Throughput Shape Based Analysis of SAXS for Self-Assembled OMIEC Blends

A major challenge of organic mixed ionic electronic conductor (OMIEC) material design is the opposing preferred morphologies of ionic and electronic transport. Many OMIECs are designed to integrate all desired properties within a single material. However, this approach often requires the synthesis of complex macromolecules. In contrast, blending components to modify compositions of composite OMIECs can greatly simplify and accelerate the molecular design process to achieve material solutions via careful (re)-formulation instead of synthesis. Blending self-assembling block copolymers (BCPs) with relatively rigid conjugated polymers (CPs) offers a promising strategy to facilitate long-range electronic transport in a new class of structured OMIEC blends. The formation of distinct ionic conducting and charge conducting domains enables the optimization of morphologies preferred by ion and charge transport yet remains close enough to maintain strong ionic-electronic coupling. The shape and order of these structures are also affected by many parameters including temperature, concentration, molecular weight, side chains, shear, etc. Thus high-throughput characterization and analysis is essential to understand the phase behavior of these co-assembled blends. To demonstrate this, hydrogel blends of BCP polyethylene oxide-polypropylene oxide-polyethylene oxide and conjugated polyelectrolyte poly[3-(potassium-4-butanoate)thiophene-2,5-diyl] were prepared with an open-source liquid handling robot. The blends were structurally characterized through high-throughput small angle x-ray scattering (HT-SAXS). A statistical analysis tool, autophasemap, was developed in our group to automatically generate phase maps that provide a hierarchical summary of the HT-SAXS experiments. This is accomplished by measuring the similarity between sampled profiles and data-based template functions and clustering the profiles based on this similarity. Multiple ordered phases of the polymer blends detected by autophasemap were then identified. In addition, these blends form monolithic oriented gels under multiple temperature and shear conditions.