A polyelectrolyte complex gel was prepared by mixing chitosan and k‐carrageenan solutions in the presence of NaCl. To study the effect of ambient pH on the swelling behavior, the diameter of the cylindrical gel(4 mm x 8 mm) immersed in aqueous NaOH, KOH, or HCl solution was measured. In the range of pH 10–12, the diameter increased with time, and the gel reached swelling equilibrium within 6 days. In an NaOH solution of pH 10.5, the maximum swelling occurred, and the volume of the gel at equilibrium was 10.2 times as large as the initial one. At pH below 9 and at pH 13, no swelling was observed. Thus, the swelling of the complex gel prepared in this study was sensitive to a rather narrow range of pH. The swelling equilibrium in the presence of NaCl was also investigated at various pH. © 1993 John Wiley & Sons, Inc.
ASJC Scopus subject areas
- 化学 (全般)