Contribution of chitin derivatives to the modification of physicochemical properties of formulations

✍ Scribed by J Desbrières

• Book ID: 104526644
• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 138 KB
• Volume: 52
• Category: Article
• ISSN: 0959-8103
• DOI: 10.1002/pi.1094

✦ Synopsis

Abstract

Chitin was modified to obtain controlled amphiphilic polysaccharides which may be either cationic (chitosan) or anionic (carboxymethylchitin). The hydrophile–lipophile balance (HLB, also called hydrophilic–hydrophobic balance) was modified with respect to different parameters (pH, degrees of substitution of ionic or alkyl groups) and the rheological and tensioactive properties of formulations based on these polymers have been studied. The presence of hydrophobic groups and interactions among themselves allow these polymers to act as thickening or gelling agents with an improved temperature stability. The surface activity of anionic carboxymethylchitins can be improved either by the addition of a cationic surfactant which plays the role of counterion by electrostatic interaction (forming a surfactant–polyelectrolyte complex, SPEC) or by N‐alkylation. The SPECs are found to be more efficient than alkyl derivatives because the necessary surfactant concentration to reach tensioactive properties is much lower than its critical micellar concentration in the pure solution.

© 2003 Society of Chemical Industry