Studies on the Electrochemical Properties of Copolymers of Maleic Acid，III On the Difference of Titration Behaviors due to Comonomer Species

The sharp difference of titration behaviors between maleic acid-vinyl acetate copolymer and maleic acid-styrene copolymer was briefly considered according to the Kirkwood model for organic ions On the other hand，the electrostatic potential of polyion with which the coil configuration was related， was estimated from the potentiometric data at low ionic strength and the comparison between two copolymers in various polymer concentrations was done. During the dissociation of the primary carboxyl group， the potential curves as the function of the degree of ionization markedly differed between two copolymers. In particular，the anomalous behavior of the styrene copolymer was considered to come from its tighter coiling. In addition， the independency of titration curves of the degree of polymerization was ascertained in two copolymers