Components and parameters of liquids and some polymers surface tension at different temperature

Abstract

The measurements of the contact angle for several apolar and polar liquids on the polytetrafluoroethylene (PTFE), polyethylene (PE), polymethyl methacrylate (PMMA) and polyamide (nylon 6) surfaces were made at 293, 303 and 313K. From the obtained contact angle for n-alkanes on PTFE the values of its surface tension at different temperatures were established. As follows this surface tension does not depend on the temperature in the range from 293 to 313K. Next, the Lifshitz-van der Waals and dispersion components of several liquids were determined from the contact angle on the PTFE surface at different temperatures by applying the same values of PTFE surface tension. The obtained components were next applied for determination of electron-acceptor and electron-donor parameters of water, formamide, glycerol and ethylene glycol surface tension on the basis of the contact angle on the PMMA surface which was assumed to be a monopolar solid. The significance of the obtained components and parameters of the surface tension of studied liquids was tested in the calculations of PE, PMMA and nylon 6 surface tension components and parameters. The calculated values of surface tension of PTFE, PE, PMMA and nylon 6 components and parameters were compared to those reported in the literature. Our calculations indicate that the surface tension of studied polymers, their components and parameters as well as the Lifshitz-van der Waals component of polar liquids practically do not depend on the temperature in the studied range.