Investigation of polyelectrolytes by total reflection X-ray fluorescence spectrometry

Water soluble polyelectrolyte samples containing mono-, bi- and trivalent metal ions were investigated without any pretreatment. Acid digestion of linear polymers may lead to a product insoluble in water so the digestion has to be avoided. The determination of analytical characteristics and limitations of the total reflection X-ray fluorescence (TXRF) analysis for poly(vinylalcohol-vinylsulfate) copolymers containing the following cations: Cs⁺; Ba²⁺; Cu²⁺ and La³⁺ are presented in this communication. On the basis of our results efficiency of ion-exchange during preparation of polyelectrolytes and stoichiometry of the end-product were determined. TXRF results were compared with data gained by inductively coupled plasma atomic emission spectrometry (ICP-AES) measurements except in the case of Cs⁺, which has poor sensitivity in ICP-AES. Good agreement was found between the results of the two techniques and calculations from titrimetric data. Concentration of Li⁺ and Mg²⁺ in polymer samples was measured only by ICP-AES.