Rotational mobility of guest molecules studied by method of oriented spin probe

摘要: Oriented spin probe method was used for study of rotational mobility di-p-anisylnitroxide in low-temperature ethanol, toluene and isopropylbenzene glasses as well glassy polystyrene, poly-(N-vinylpyrrolidone) polyvinyl butyral matrixes. Alignment molecules initially isotropic samples induced by polarized light irradiation (photoselection phenomenon). The temperature dependencies relaxation alignment were measured. light-induced found to complete near the glass transition temperature. A step-type alignment on a time scale minutes has been range 150–300 K butyral. results are dramatic contradiction with commonly known rotational correlation times polymers obtained traditional method. nonlinear least-squares fitting experimental EPR spectra treatment this contradiction. Quantitative agreement simulated 77–300 achieved simply using model quasi-libration. By term we mean that molecules stochastic fast angular motion anisotropic cage matrix. average displacement at ∽300 estimated 5–15°.