Collaborative Research: Processing Films from Multi-Functional Polymer Dispersion Blends

North Carolina State University, Raleigh NC

Investigators

Abstract

Polymer dispersions are a general class of materials in which fine particles of polymers are dispersed in water. These materials are used commonly in several industries, including medicine, paints and coatings, automobiles and plastics, and equipment exists for processing these traditional polymer dispersions. However, processing thin films from multi-functional polymer dispersion blends (combining two or more types of dispersed particles) poses a significant challenge due to lack of fundamental understanding. Control over film properties is extremely difficult because minor changes in polymer dispersion processing conditions or chemistry can lead to unpredictable particle sizes and shapes. This award will enable a path towards the rational design of polymer dispersion blends to achieve films with multifunctional properties, such as films with responsive optical properties, reusable anti-microbial films, and mechanically-robust organic solar cells. The new knowledge generated by this award has the potential for rapid impact on existing industrial applications by helping them become more sustainable, as well as the development of new applications. This award will provide research opportunities to underrepresented groups in science and engineering and help disseminate science and engineering knowledge to the public. The overall goal of this research is to establish fundamental process-structure-property relations to guide the predictive design of blended polymer dispersions for multi-functional applications. This work will use a systematic, synergistic and iterative approach among simulations, synthesis and characterization to understand the morphology and self-assembly of multiple components with variable miscibility in a solvent, such as emulsions comprising two or more organic macromolecules, primary organic solvent, secondary co-solvent, surfactant, and water. Polymer dispersions will be simulated by a mesoscale computational method that has been used to study and predict the phase behavior and properties of emulsification, polymer aggregates, and complex self-assembled structures. Emulsion-based, resonant infrared matrix-assisted pulsed laser evaporation will be used for the thin-film deposition of polymer dispersions, which is critical to eliminate the mutual dependence between the emulsion process and the nature of film formation. This deposition process, specifically the laser-target interaction and laser-generated plume characteristics, will be explained using coarse-grained molecular dynamics. The deposited films will be investigated using standard materials and device characterization techniques. The outcomes of this work will provide a predictive theoretical framework to elucidate the mechanisms that determine how disparate polymer dispersions blend in solution and in films.