The Structural Stabilization of Polymers: Fractal Models

This monograph deals with the structural aspects of transport processes of gases, physical ageing and thermo-oxidative degradation of polymers in detail. Fractal analysis, cluster models of the polymer structureaEURO (TM)s amorphous state as well as irreversible aggregation models are used as main structural models. It is shown that the polymer structure is often a more important parameter than its chemical construction. Another significant aspect is the structural role in polymer melts oxidation. The basis for understanding of structural stabilisation gives anomalous diffusion of oxidant molecules on the fractal structure for both solid state polymers and polymeric melts. The important part of this problem is structure connectivity characterized by its spectral dimension. Therefore branched (cross-linked) polymers have smaller diffusivity in comparison with linear polymers.