Structural relaxation of poly(γ-benzyl- l-glutamate)

A structural relaxation process similar to that in amorphous polymers has been found in poly(γ-benzyl- l-glutamate). Its kinetics has been determined by differential scanning calorimetry and modelled using a phenomenological model. The parameters characterizing the shape and temperature dependence of the distribution of recovery times have been compared with those describing the dielectric relaxation process, occurring in the same range of temperatures. The process is ascribed to conformational rearrangements of the side chains and is responsible for the glass transition and the WLF behaviour of the dielectric relaxation described in the literature.