Thermodynamic compatibility of poly(ethylene oxide) and poly(ethylene glycol) under deformation

Using DTA, DSC, X-ray diffraction, and viscometry, the phase transitions and phase state of the poly(ethylene oxide) (PEO)-poly(ethylene glycol) (PEG) system under static conditions and in a shear stress field were studied. It was demonstrated that the application of a mechanical field not only leads to an increase in the crystallization temperatures of the polymers of interest but also brings about a change in the crystalline to amorphous phase separation with a UCST over a wide composition range. The concentration dependences of the parameters of thermodynamic interaction of PEO and PEG were calculated, and the sizes of macromolecules of polyethers in the systems under deformation were assessed.