Metal palladium dispersed inside macroporous ion-exchange resins: rotational and translational mobility inside the polymer network

Commercial macroporous strongly acidic ion-exchange resin (Bayer UCP 118) i n its acidic and Na+ forms and a resin/Pd composite were investigated by me ans of electron spin resonance (ESR) and pulse field gradient spin echo-nuc lear magnetic resonance (PGSE-NMR) techniques, to determine their molecular accessibility to 2,2,6,6-tetramethyl-4-oxo-1-oxypiperidine (TEMPONE) disso lved in water and the molecular mobility of both TEMPONE and water inside t heir accessible domains. The paramagnetic probe and water itself occupy bot h the micro- and macroporous domains of the resin particles, among which a rapid exchange is observed. (C) 2000 Elsevier Science B.V. All rights reser ved.