Spectral profiling of radicals in polymer degradation based on electron spin resonance imaging(ESRI)

摘要

We have developed 1D and 2d electron spin resonance imaging(ESRI)in order to deduce the spatial variation of radical prop- erties in polymers exposed to UV radiation in the presence of oxygen, or thermally treated. The accelerated degradation of poly (acrylonitrile-butadiene-styrene)(ABS)containing Tinuvin 770 as the hindered amine stabilzer(HAS)was studies in a weathering chamber equipped with a Xe source that mimics the spectral range of sunlight. The HAS-derived nitroxides detected by ESR occupy two sites and were assigned to radicals located in domains differing in their monomer composition.