Investigations of polydienes with various chemical structures and microstructures were carried out, and interrelations of molecular-structural characteristics of polydienes with their macroscopic properties in thermo-oxidation processes were shown. An experimental-formal approach to substantiation of cross-linking and destruction depth of carbon-chain linear polydiene macromolecules is proposed. The extrapolation value of the molecular weight of the chain ensuring activation of chemical reactions of vulcanization and oxidation was obtained. It is proposed to use the criterion of destruction for calculating the number of chain splinters resulting from macromolecule ruptures