Amphiphilic N-[2(3)-(dodec-2'-en-l-yl)succinoyl]chitosan (DDC-chitosan) of varying degree of substitution was synthesized by the reaction of chitosan with (2-dodecen-1-yl)succinic anhydride in 1% acetic acid/methanol (1:1 v/v) solution. A degree of substitution (5-30 mol.%) depended on anhydride/amino group ratio. Surface tension activity, rheological and foam-forming properties of DDC-chitosan were strongly determined by the degree of substitution. Viscosity experiments revealed inter/intramolecular interactions of DDC-chitosan macromolecules in aqueous solutions. These interactions were most pronounced at substitution degrees higher than 10 mol.%, while the surface tension activity and the foam-forming ability of DDC-chitosans were maximal at the substitution degree of 5 mol.%. (C) 2007 Elsevier Ltd. All rights reserved.