The study of relaxational properties of molecular networks of polyoctafluoroamyl methacrylate by photoelasticity and torsion pendulum methods

Abstract The time dependencies of photoelasticity and the temperature dependencies of the mechanical properties of films of copolymers of octafluoroamyl methacrylate with ethylene glycol dimethacrylate have been studied. Three regions of mechanical loss were found. The transition at 170° is related to local processes in side groups. The main α-maximum of relaxation is due to segmental mobility; the λ-maximum at 120–150° is determined by cooperating processes of segmental mobility: the α-process is satisfactorily described by a bimodal distribution of relaxation times. The dimensions of kinetic units and the activation energies of fast and slow α-relaxation processes have been determined. The mean size of the kinetic units of the α-process is increased with increasing concentration ν of ethylene glycol dimethacrylate, affecting the degree of crosslinking of the copolymer network.