Using Supercomputers to Help Design Quality Recyclables from Plastic

Published April 24, 2024

 Credit: Cell Reports: Physical Science journal.

By Kimberly Mann Bruch, SDSC Communications

From the containers that hold our food to the packaging that protects our purchases, plastic products have become indispensable in our daily lives. The properties of these useful materials, however, make them challenging to dispose of responsibly. As a result, they've accumulated in our environment, posing serious threats to ecosystems and human health.

Senior Associate Dean for Faculty Affairs at the McCormick School of Engineering and Applied Science at Northwestern University Linda Broadbelt has been leading a team of researchers to tackle the plastic waste problem — with the help of ACCESS allocations on Expanse at the San Diego Supercomputer Center (SDSC) at UC San Diego.

According to Broadbelt, one promising approach to this complex issue is computationally constructed chemical recycling — a process that uses supercomputer models to help determine the best way to break down plastics into their basic building blocks, called monomers. The latest models for this process outlined by Broadbelt and her team have been published in the Cell Reports: Physical Science journal.

“When we can create plastics that don’t lose their quality during the recycling process, we can create a circular economy where plastics can be continuously recycled,” Broadbelt said. “To achieve this, we have been using Expanse to illustrate a complex chemical process that requires careful consideration of thermodynamics, kinetics and other factors.”

Broadbelt’s work specifically delves into the "ceiling temperature" (Tc) in designing recyclable polymers. Understanding Tc — a type of temperature threshold that determines whether a polymer can be efficiently recycled back into its monomer form — helps researchers rank different polymers based on their ability to be recycled.

“By combining experimental data with Expanse simulations, we can better understand Tc and predict key thermodynamic parameters,” Broadbelt explained. “When we can see the details of how polymers behave under different conditions, we can design more sustainable materials.”

She said that the team’s most recent study has made progress and their next steps are to examine challenges such as the influence of various solvents and their concentrations as those play a big role in Tc.

Computational work on Expanse was funded by the U.S. National Science Foundation ACCESS (grant no. CTS120055).