Fig. 1: The styrene-butadiene copolymer and radical scavengers.
From: The molecular mechanism of constructive remodeling of a mechanically-loaded polymer
The sheared polymer had Tg = −35 °C and contained 30.5 ± 0.5% and 27.1 ± 0.7% by mass of styrene (blue) and 1,2-enchained butadiene (green), respectively, with the rest being 1,4-enchained butadiene (red), as determined by NIR spectroscopy (Supplementary Fig. 1). AH represents a class of antioxidant additives routinely used for protection of commercial polymers against thermooxidative aging38,39. A• is a radical scavenger produced in situ when a macroradical abstracts phenolic hydrogen atom from AH. T• combines a well-established radical trap40 (TEMPO) with pyrene, whose characteristic absorption spectrum allows simple and accurate spectroscopic quantitation of the number of T moieties bound to a polymer chain. Bulk concentrations of AH and T• used in a subset of our experiments are also listed.
