The polymers that were studied include polymethacrylic acid (PMAH) and polyacrylic acid (PAH), as well as its sodium salt and the sodium salt of the polystyrènesulfonate. ###>Les polymères étudiés furent l'acide polyméthacrylique (HPMA) et l'acide polyacrylique (HPA) ainsi que son sel de sodium, de même que le polystyrènesulfonate de sodium.