Phase equilibrium and interdiffusion in the oligo(3,3-bis(azidomethyl)oxetane)-oligo(3-methyl-3-azidomethyloxetane) system

Intersolubility and interdiffusion in the oligo(3,3-bis(azidomethyl)oxetane)-oligo(3-methyl-3-azidomethyloxetane) binary system are studied. The components of the system differ in symmetric and non-symmetric positions of azide groups along the polymer chain, respectively. The chemical and conformational features ensure the ability of oligo(3,3-bis(azidomethyl)oxetane) to crystallize at temperatures of ∼50°C. The system of azidooxetane oligomers is characterized by a simple crystalline equilibrium crystal-melt. The generalized phase diagram of the binary system is constructed. The interdiffusion zones of oligomers are analyzed in detail in a wide temperature range, and a number of specific effects manifesting themselves during their intersolubility are observed. The concentration and temperature dependences of diffusion coefficients are examined, and the activation energies of diffusion are calculated.