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Crosslinking of chitosan fibers with dialdehydes: Proposal of a new reaction mechanism

✍ Scribed by Jonathan Z. Knaul; Samuel M. Hudson; Katherine A. M. Creber

Publisher
John Wiley and Sons
Year
1999
Tongue
English
Weight
281 KB
Volume
37
Category
Article
ISSN
0887-6266

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✦ Synopsis

A highly deacetylated chitosan from shrimp with a degree of deacetylation of 95.28 Ϯ 3.03% was prepared and spun into a monofilament fiber using a solution of 4% (w/v) chitosan in 4% (v/v) aqueous acetic acid. Samples of the spun fibers were immersed in aqueous solutions containing glutaraldehyde and glyoxal, and subsequently washed and dried. When the concentration of crosslinking agent was varied at room temperature over a constant time of 1 h, dry mechanical properties improved up to a point after which increasing concentrations resulted in degradation. Immersion time was also varied between 1 and 60 min at 25.8°C, and temperature was varied between 25.8 and 70.0°C, at fixed concentrations of both glyoxal and glutaraldehyde. It was demonstrated that mechanical improvements might be rendered at higher temperatures over lesser times. However, it was also shown that at higher temperatures, fiber mechanical properties would begin to diminish. Chitosan films were subjected to similar treatments in aqueous crosslinking solutions. Fourier transform infrared data (FTIR) on the films suggest that some interaction is occurring between the glutaraldehyde or glyoxal and the amine group on the chitosan backbone.

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