Quantitative analysis of the dispersion interaction of liquids with the surface of gamma-irradiated PTFE

Hamaker constants were calculated for the PTFE/PTFE, PTFE/tetradecane and PTFE/water systems (PTFE — polytetrafluoroethylene) using various dielectric models. It is shown that the choice of dielectric model significantly affects the absolute values of the Hamaker constants and has virtually no effect on their relative changes depending on the density and dielectric increment of PTFE. The total calculated changes in the adhesion work due to van der Waals interactions, taking into account changes in density and dielectric increment in gamma-irradiated PTFE, do not exceed 11% for all dielectric models used. It is concluded that changes in surface energy upon PTFE irradiation cannot be explained by an increase in the contribution of the van der Waals interaction due to polar radiolysis products. It is necessary to take into account the electrostatic interaction of stabilized charges with dipoles of the polar liquid.