Novel pH-sensitive chitosan hydrogels: swelling behavior and states of water
2000 (English)In: Polymer, ISSN 0032-3861, E-ISSN 1873-2291, Vol. 41, no 12, 4589-4598 p.Article in journal (Refereed) Published
Physically crosslinked chitosan hydrogels were synthesized by grafting D,L-lactic acid (LA) and/or glycolic acid (GA) with different feed ratios. The physical crosslinking was formed due to the hydrophobic side chains aggregation and intermolecular interactions through hydrogen bonds between side and main chains. The crystallinity of original chitosan decreased by grafting LA and GA. The structural change of the hydrogels in different pH buffers was characterized by FT-IR method and the results were interpreted. Differential scanning calorimetry (DSC) was used to probe the states of water in the chitosan hydrogels. Three types of water were found in the samples, i.e. freezing water (namely free water), non-freezing water (namely bound water), and freezing bound water, while there are variations in the amount of bound water for different hydrogels. The effect of hydrophobic side chains on water state and swelling behavior were discussed.
Place, publisher, year, edition, pages
2000. Vol. 41, no 12, 4589-4598 p.
chitosan, D,L-lactic acid, glycolic acid, differential scanning calorimetry, semi-ipn hydrogel, graft-copolymerization, polymers, acid), gels, kinetics, mixtures, release, systems
IdentifiersURN: urn:nbn:se:kth:diva-19657ISI: 000086228500027OAI: oai:DiVA.org:kth-19657DiVA: diva2:338349
QC 201005252010-08-102010-08-10Bibliographically approved