Home – Home – Jornals – Chemistry for Sustainable Development 2004 number 5

Four topological structures of polytetrafluoroethylene (PTFE) have been found by using thermomechanical spectroscopy (TMS): amorphous structure and three crystalline (high-melting, intermediate, and low-melting) modifications. Gamma irradiation of PTFE showed that both free volume and molecular mass remain practically unaffected in the pseudoreticular structure of the amorphous block. In the crystalline phase, gamma irradiation reduces the molecular weight of the crystallized chains of the low-temperature modification; the intermediate and high-temperature crystalline phases disappear as a result of their transformation into the amorphous structure. Quantum-chemical simulation of the F₃