ESR study on molecular motion of peroxy radicals of polytetrafluoroethylene

Abstract Temperature variations of the line shapes of e.s.r. spectra from the peroxy radicals of polytetrafluoroethylene ( ptfe ) were investigated in detail and the results were quantitatively analysed based on Kneubuhl's theory on the line shape. It was found that there were two kinds of rapid molecular motions, of which the correlation times were about 10 −9 s, for the peroxy radicals of ptfe ; one was the rotational motion related to the peroxy chain radical, the other was the three dimensional motion associated with the peroxy end radical. The activation energies of these molecular motions were estimated as 0·52 kcal/mol and 0·26 kcal/mol for the rotational motion and the three dimensional motion, respectively. Origins of such rapid motions were discussed in connection with the other molecular motions of polymers, which were found by other experimental methods.