Electron spin resonance spectra of poly(methyl methacrylate) irradiated at 77°K

Abstract

Abstract It is shown that there exists a difference in the electron spin resonance spectrum of poly(methyl methacrylate) irradiated with electrons and observed at 77°K. and that at room temperature. One of the radicals trapped at 77°K. is probably ·COOCH 3 , which gives the spectrum of a single line, and the others giving triplet and quartet are perhaps ·CHO and ·CH 3 , the splitting of which are 132 gauss and 23 gauss, respectively. With the elevation of the annealing temperature the unstable radicals recombine or convert to the stable radicals; near room temperature they are completely replaced by the stable radical which gives the nine‐line spectrum.