Synthesis of lauryl grafted sodium alginate and optimization of the reaction conditions

Lauryl grafted sodium alginate (SA-C-12) was prepared by the reaction between sodium alginate and dode-canol with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) as a coupling agent. The structure of SA-C-12 was confirmed by FT-IR, H-1 NMR, and thermoanalysis. Meantime, the degree of substitution (DS) of SA-C-12 was determined by GC. The reaction conditions were studied systematically, which included reaction time and temperature, the molar ratio of hexuronic acid in alginate to dodecanol (N-hexuronic/N-dodecanol) and N-hexuronic/N-EDC, the mass of toluenesulfonic acid. By investigating the relationship between these conditions and DS, the optimal conditions with the maximum DS were obtained. (C) 2011 Elsevier B.V. All rights reserved.