Studies on chitosan and poly(acrylic acid) interpolymer complex. I. Preparation, structure, pH-sensitivity, and salt sensitivity of complex-forming poly(acrylic acid): Chitosan semi-interpenetrating polymer network

✍ Scribed by Hanfu Wang; Wenjun Li; Yuhua Lu; Zhiliang Wang

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 180 KB
• Volume: 65
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19970822)65:8<1445::aid-app1>3.0.co;2-g

✦ Synopsis

A novel semi-interpenetrating polymer network (semi-IPN) membrane composed of crosslinked chitosan(cr-CS) and poly(acrylic acid) (PAA) was prepared. Evidence from infrared spectra proved the formation of polyelectrolyte complex through electrostatic interaction between NH / 3 groups from CS and COO 0 groups from PAA. The semi-IPN membrane swelled at high pH and at low pH exhibited a typical pHsensitivity. Its swelling degrees in different salt solutions with the same ionic valence and equal ionic strength were on similar levels. Under certain ionic strength ( I Å 1.5 mol/L), the degree of swelling increased with increased metal ionic valence. Furthermore, the elongation of the semi-IPN membrane could vary reversibly by immersion into CaCl 2 solution and KCl solution alternately. Reasons for the chemomechanical behavior are discussed.