Synthesis Of Anionic Sugar-Based Surfactants And Their Properities

A series of sugar-based sulfate anionic surfactants were synthesized from the reaction of gluconolactone with different aliphatic amines (C=8, 12, 18), and subsequent sulfation with sulfur trioxide and neutralization. The products and intermediates were characterized with ESI-MS. The conditions for the lactone ring-opening amidation were controlled at the molar ratio of gluconolactone to amine about 1:1.1, ethanol as solvent, the reaction temperature below 80°C. The lowest surface tensions (γCMC) of these series anionic surfactants at 20℃were 35.5mN/m,28.71mN/m and 35.2mN/m respectively and the critical micellar concentrations were 31.4g/L,2.89g/L and 0.05g/L respectively. The sulfated N-dodecyl sugar-amide demonstrated the best foaming stability. The wetting ability were in order C8>C12>C18. The emulsification capability of these anionic surfactants for dodecane was in order C12>C18>C8 while for liquid wax was in order C18>C12>C8.Similarly, sugar-based sulfate anionic surfactants were synthesized from the reaction of 2-amino-2-deoxyglucose with aliphatic acyl chloride (C=12; 18), and subsequent sulfation with sulfur trioxide and neutralization. The products and intermediates were characterized with ESI- MS. The conditions for the N-acylation were controlled at the molar ratio of 2-amino-2-deoxy- glucose to acyl chloride about 1:1.1, 1:1 ethanol /water as solvent , the reaction temperature below -15°C. The lowest surface tension (γCMC) at 20℃were 34.86mN/m,44.7mN/m respectively and the critical micellar concentrations were 0.57g/L and 0.62g/L. The foaming stability and wetting ability were both C12>C18. The emulsification capability for n-dodecane was C 12>C18 while for liquid wax was C18>C12.