ABSTRACT
Spin labels and probes came into the arsenal of physical methods for the investigation of polymer systems. Spin label and probe technique had its origin in the 1960s with the advent of a new class of organic free radicals — nitroxides, and with advances in electron paramagnetic resonance (ESR) spectra analysis. Long-lived paramagnetic molecules-stable radicals — were known long before the discovery of the ESR phenomenon. Nitroxide disulfonate was known in the last century. In the first half of the century, tens of stable organic radicals were synthesized. One of the most fruitful and ingenious applications is the investigation of the rotational and translational dynamics of spin probes in polymeric systems. Structural variation of nitroxides enables trends and characteristics of small molecules motion to be found. The experimental technique for the investigation of the spin probe rotation anisotropy has been published. The correct technique for this purpose is the high resolution ESR.
