GOALI: Collaborative Research: On-Demand Continuous-Flow Production of High Performance Acrylic Resins: from Electronic-Level Modeling to Modular Process Intensification

Drexel University, Philadelphia PA

Investigators

Abstract

The proposed collaborative research project between two academic groups and an industrial partner, Axalta Coating Systems (formerly DuPont Performance Coatings), aims to investigate the effects of molecular oxygen on free-radical polymerization (FRP). The effects of molecular oxygen can be either catalytic, at high temperatures, or inhibitory, at low temperatures. The majority of FRP studies with molecular oxygen have focused on its inhibitory effects, so it will be of great fundamental interest to discover the mechanisms of oxygen-based catalysis under different reaction conditions. To translate this finding into practical industrial processes, it is vital to understand how the concentration of molecular oxygen influences reaction rates and resulting polymer conversion and microstructure. The team proposes to: (a) Identify the most likely mechanisms for polymer-chain initiation by molecular oxygen and the departure of oxygen from live polymer chains before they are terminated, using Density Functional Theory (DFT); (b) Design and conduct batch polymerization experiments to capture the initiating and product species and to verify the theoretically-predicted species and mechanisms; (c) Develop a macroscopic mechanistic model of an oxygen-initiated polymerization tubular reactor (PTR) to perform model-based design; and (d) Develop a modular PTR design that intensifies and modularizes acrylic resin processes. The reduction or elimination of conventional thermal initiators (normally the most expensive component of a resin) will lower the operating costs. The elimination of residual groups left by conventional initiators in the final product (which adversely affect polymer properties such as UV resistance) and the optimal operation of FRP reactors will improve the resin quality. Beyond acrylates, the outcomes of this research may impact every free-radical polymerization process. In addition to training two graduate students, the team plans to create computer modeling modules and projects to provide research training opportunities to undergraduates selected from underrepresented groups through Drexel's Co-op program and UPenn's Vagelos Integrated Program in Energy Research (VIPER). This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.