Fig. 6
From: Leveraging mechanochemistry for sustainable polymer degradation
a Identification of primary scission radicals during the fracture of PE: Measured (above, observed after sawing of PE) and simulated (below, assuming a primary chain-end radical) ESR spectra. Adapted from Sohma and coworkers [99]. b Commonly used agents in ESR spectroscopic studies of polymer fracture: (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO, b1), pentamethylnitrosobenzene (b2), and bis(2,2,6,6-tetramethyl-4-piperidyl-1-oxyl) sebacate (a hindered amine light stabilizer, b3). c ESR spectrum after extrusion of PP under air with b3 as a radical stabilizer at 230 °C. Reprinted from Sohma [103]. d Comparison of ESR intensity as a measure of the amount of radicals generated at 230 °C with and without mechanical activation (extrusion) under air with b3. Reprinted from Sohma [103]. Graphics are reproduced with permission from Springer Nature
