Molecular Weight Evolution in Polymer Upcycling: Extracting Rates and Identifying Mechanistic Signatures

graph: Reaction time vs ProductScientific Achievements

Universal aspect

Average molecular weight vs. time has universal shape that helps to determine rates, but not to identify mechanisms

computational equation

16 categorized mechanisms 

  • Homogeneous or heterogeneous?
  • From solvent or from the melt?
  • End-scission or random scission?
  • Non-processive or processive?

Examples:

Left: heterogeneous, solvent, random-cut, non-processive; Right: heterogeneous, melt, random-cut, non-processive.

graph of computational methodsComputational methods

Developed framework to formulate and solve coupled bulk population balances, bulk species balances, and surface-adsorbed population balances. 

Significance and Impact

Practical tools to extract quantitative rates and recognize the underlying mechanisms from experimental molecular weight distributions. 

Yappert, R.; Peters, B., J. Mater. Chem. A 2022, 10, 24084-24095. https://doi.org/10.1039/D2TA04628H 

iCOUP, an EFRC Supported by Basic Energy Sciences