The Influence of Deformation and Chemical Composition on Elementary Free Volumes in Glassy Polymers

A relation between positronium annihilation characteristics and concentration of elementary free volumes is considered for the case of positronium formation before its localization. We estimated the diffusion coefficient of nonlocalized positronium (≈10$\text{}^{-4}$ cm$\text{}^{2}$/s). The positron annihilation lifetime studies of uniaxial compression and annealing of some glassy polymers revealed variations of the shape of elementary free volumes size-distributions.