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

Lauryl grafted sodium alginate (SA-C12) was prepared by the reaction between sodium alginate and dodecanol with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) as a coupling agent. The structure of SA-C12 was confirmed by FT-IR, 1H NMR, and thermoanalysis. Meantime, the degree of substitution (DS) of SA-C12 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 (Nhexuronic/Ndodecanol) and Nhexuronic/NEDC, the mass of toluenesulfonic acid. By investigating the relationship between these conditions and DS, the optimal conditions with the maximum DS were obtained.