Effect of PEG 400 Nanocrystal Sizes on Thermal and Spectral Properties

Abstract

This paper studies the effect of silica gel pore size on the thermal and dielectric properties of Polyethylene glycol (PEG) nanocrystals and the mechanisms of thermal mobility of molecules during relaxation processes and phase transitions. The DSC method was used to study thermophysical properties. Dielectric relaxation in bulk PEG and PEG nanocrystals was studied by dielectric spectroscopy. It was established that the position of the relaxation process for PEG shifts toward low temperatures with a decrease in the pore size. It was also shown that as the pore size decreases, the temperature and heat of fusion of PEG nanocrystals decrease. Such shifts are associated with the occurrence of additional stresses in the nanocrystals caused by the interaction with the silica gel wall.