Electron paramagnetic resonance studies of polymers

This article provides a non-exhaustive overview of the contribution of electron paramagnetic resonance (EPR) to the study of polymers. Applications include the study of polymerization, degradation, stabilization and finishing processes. Following McConnel's work , the use of nitroxide radical probes has opened up new fields of application. These probes provide information on polymer microstructures and the local viscosity of the media in which they are incorporated .

Because of its specificity and high sensitivity (10 ^-9 mol/L), EPR enables direct detection of free radicals. A free radical is a molecule or fraction of a molecule with an incomplete outer electronic layer, in other words, an unsatisfied bond. The availability of commercial spectrometers has made them the tool of choice for both fundamental and applied research.