The polarographic behaviour of hydrolyzed propene-maleic anhydride cop
olymers in the interval pH 2.0-11.0 has been investigated by different
ial pulse polarography in aqueous lithium chloride solution at 25 degr
ees C. In dependence on the pH-value, one, two or three signals, belon
ging to the acid groups in the copolymer, appear in the polarograms. T
hree apparent polarographic acid constants have been determined graphi
cally from the changes in the halfwave potential of the separate peaks
in correlation with pH.