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Updated: Mar 3, 2026

A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes
Published on: February 27, 2017
Impact of Stereocontrolled Polynorbornene Synthesis on Degradation Rate
Britney Baez1, Greyson Karis-Sconyers1, Ethan Flanagan1
1Department of Chemistry, Harvey Mudd College, Claremont, California 91711, United States.
None:
We synthesized a family of polynorbornenes with a wide range of cis/trans compositions by ring-opening metathesis polymerization (ROMP) with a variety of ruthenium catalysts and subjected these materials to ultrasonication as a proxy for mechanical degradation. Increasing the cis-alkene content enhanced the degradation rate for both short (∼70 kDa) and long (∼700 kDa) polynorbornenes. These data suggest that the heightened allylic strain in cis- versus trans-polynorbornene promotes faster degradation independent of molecular weight under mechanical stress. Our results complement existing plastics recycling research by isolating the understudied relationship between backbone stereochemistry and degradability.
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