Kinetics of volume change of poly(succinimide) gels during hydrolysis and swelling

• Published in: Physical chemistry chemical physics : PCCP 2010-10, Vol.12 (39), p.1267-12675
• Main Authors: Varga, Zsófia, Molnár, Kristóf, Torma, Viktoria, Zrínyi, Miklós
• Format: Article
• Language: English
• Subjects: Aspartic Acid - analogs & derivatives; Aspartic Acid - chemistry; Biocompatible Materials - chemistry; Chemistry; Exact sciences and technology; Gels - chemistry; General and physical chemistry; Hydrogen-Ion Concentration; Hydrolysis; Kinetics; Peptides - chemistry
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/c0cp00527d

Kinetics of hydrolysis induced swelling as well as pure swelling of a novel class of pH responsive biocompatible polymer gels was studied. Poly(aspartic acid) gels were prepared by hydrolysis of chemically cross-linked poly(succinimide) networks. The volume change of spherical gels of different size, measured at constant pH, proceeds in three distinct processes: solvent exchange, hydrolysis and swelling. It turned out that pure swelling as well as the swelling coupled with hydrolysis can be described by the Tanaka-Fillmore-Peters-Candau theory. The relaxation times as well as the cooperative diffusion coefficient of the network chains were determined. It was found that the initial condition of the swelling makes its influence felt neither on the relaxation time, nor on the cooperative diffusion coefficient. The volume change of poly(succinimide) gel includes three subsequent processes: solvent exchange, hydrolysis, and swelling.