DIFFUSION AND SORPTION OF ORGANIC LIQUIDS THROUGH POLYMER MEMBRANES .1. POLYURETHANE VERSUS NORMAL-ALKANES

Sorption and diffusion studies of n-alkanes through a commercial polyurethane membrane have been investigated in the temperature interval of 25-60-degrees-C. Liquid diffusivity through polyurethane was measured by using the immersion/weight gain method and the diffusion mechanism was explained in terms of the Fickian model. The activation energies of sorption and diffusion processes have been estimated and used to investigate the thermodynamic interactions between polyurethane chains and n-alkanes. Furthermore, sorption data were used to estimate the molar mass between crosslinks of the network polymer.