Chemical Activation of AgNO3 to Form Olefin Complexes Induced by Strong Coordinative Interactions with Phthalate Oxygens of Poly (ethylene phthalate)

AgNO3 is inactive as an olefin complexing agent and is not easily reduced to metallic silver. Poly(ethylene phthalate) (PEP) was used to induce the dissociation of AgNO3 into free ions, resulting in more active complexation with propylene. The free ion formation is mainly due to the strong interactions of silver ions with phthalate oxygens, as confirmed by Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). Furthermore, increased silver ion complexation with propylene in the electrolyte membrane of PEP/AgNO3 polymer was confirmed by the improved separation performance of propylene/propane mixtures, compared to a poly(2ethyl-2-oxazoline) (POZ)/AgNO3 membrane. In addition, the separation performance for the former remained unchanging for a longer period of time than that for the latter.