Effect of γ-radiation on the molecular-topological structure of polytetrafluoroethylene

Four topological structures of polytetrafluoroethylene (PTFE): amorphous and three crystalline (high-melting, intermediate, and low-melting forms) blocks, were revealed by the technique of thermomechanical spectroscopy. The gamma-irradiation of PTFE leaves both free volume and the molecular-mass characteristics in the pseudo-network structure of the amorphous block practically intact. In the crystalline phase, gamma-irradiation decreases the molecular mass of crystallized chains of the low-temperature modification and leads to the disappearance of the intermediate and high-temperature crystalline phases as a result of their transformation into the amorphous phase.