Synthesis and Characterization of A Rosin Gemini Surfactant

摘要

Rosin is reputed as green petroleum because it is renewable, not expensive, and environmental friendly. China is rich in rosin resources. In the paper, rosin was used as material to prepare a rosin Gemini surfactant, bisquaternary ammonium salt(BQA) of rosinate. The specific method was as follows: firstly, the rosin was modified by acrylic acid and a carboxylic acid group was introduced to the rosin. Secondly, the modified rosin reacted with the epoxy chloropropane, the intermediate I was obtained by the way. Thirdly, the intermediate reacted with dimethylamine in the mole ratio of 1:3, the reaction time of 4.5h at 80°C. By this way the intermediate II was synthesized. Finally the intermediate II reacted with the epoxy chloropropane and distilled water in the mole ratio of 1:3:3, the reaction time of 4.5h at 80°C. Liquid chromatography(LC) analysis proved that the purity of the product was 90.8% and the yield of BQA was 67%. The chemical structure of this rosin derivative as a BQA was also conformed by Fourier Transform infrared spectroscopy (FTIR), 1H nuclear magnetic resonance(NMR) analysis. As Gemini surfactant, the surface activities of the product were characterized. Its critical micellar concentration(CMC) was 4.0x10"4mol/l. Its foaming power of the product was 250mm at Os, 200mm at 5min. The emulsifying power of the product was 56min. Since the product has good surface activities and it is obtained easily from rosin. It has a promising future as a surfactant.