Application of Raman spectroscopy to industrial membranes. Part 1—polyacrylic membranes

Abstract
Industrial membranes (made of polyacrylic acid chains grafted onto a polyethylene matrix), immersed in heavy water, were studied by Raman spectroscopy. The homogeneity of the graft density was sufficient to permit the determination of relative graft rations of different samples. Plots of measured ionization versus the pH of solutions in equilibrium with immersed membranes lad to intrinsic pK determinations. For this kind of membrane, it was established that the average lengths of the polyacrylic chains are of the same order of magnitude. Consequently, the different graft ratios depend only on graft density.