2021 journal article
Tracking the complete degradation lifecycle of poly(ethyl cyanoacrylate): From induced photoluminescence to nitrogen-doped nano-graphene precursor residue
POLYMER DEGRADATION AND STABILITY, 195.
author keywords: Polyethylcyanoacrylate; Polymer degradation; Photoluminescence; Amorphous carbon; Graphene; Nitrogen-substituted graphene
UN Sustainable Development Goal Categories
3. Good Health and Well-being
(Web of Science)
Source: Web Of Science
Added: December 6, 2021
Poly(ethyl cyanoacrylate) (PECA) is a commercial polymer which degrades easily at temperatures between 150 - 200 °C via an unzipping reaction where volatile monomer is produced. In this report, the complete moderate-temperature degradation lifecycle is delineated, which also includes formation of a carbonaceous by-product where the ester side groups are lost and ring formation between the backbone and cyano side group occurs. Degradation-induced photoluminescence is observed at an intermediate point where the remaining PECA (or re-polymerized oligomers) has sp3 carbons but sp2-carbon-containing clusters of the by-product that will ultimately form aromatic structures are also present. This observation supports the hypothesis that degradation-induced photoluminescence in polymers, which has been observed widely, is connected to the formation of such sp2 containing clusters, and that this process is relatively independent of the original polymer chemistry, as PECA dominantly degrades through a mechanism distinctly different than the thermo-oxidative cascade associated with many thermoplastic materials. As degradation further advances, a residue of approximately 8% of the original mass is produced which is no longer photoluminescent and can ultimately transform into nitrogen-substituted nano-graphene. Observing the entire lifecycle further solidifies the previously-proposed connection between degradation-induced luminescence in polymers and photoluminescence in hydrogenated amorphous carbon. The low degradation temperature of PECA also provides a bridge between classic polymer degradation and waste-to-graphene strategies that generally involve much more aggressive processing.