Gemini surfactant synthesis and characterization
|Keywords||Gemini surfactants Synthesis Surface tension Surface properties|
Gemini surfactants are a special molecular structure of a new generation of surfactants, it will be two single-stranded single head group conventional surfactants in ionic head group linked together by chemical bonds , due to the electrical repulsion between the ionic head group role to each other tend to be separated is greatly reduced , greatly improves the surfactant . Synthesis of a series of Gemini surfactants , i.e. N , N' - bis - octanoyl- ethylenediamine sodium diacetate , N , N' - bis - decanoyl ethylenediamine sodium diacetate , N , N ' - bis - lauroyl ethylenediamine diacetate , sodium affecting the synthesis of ethylenediamine bis -ethyl sulfonate and N , N' - bis - fatty acyl ethylene diamine by infrared spectroscopy and nuclear magnetic resonance made ??Structural Characterization the ethanesulfonate reaction factors discussed to identify the optimum conditions for the synthesis of intermediate synthesis conditions as sodium vinyl sulfonate and ethylenediamine molar ratio of 2.2:1 , at 50 ° C. the reflux temperature of the reaction 5h ; N , N' - bis - octanoyl- ethylenediamine sodium diacetate optimal synthesis conditions : a mixed solution of water and acetone as the solvent , the intermediate with octanoyl chloride molar ratio of 1:2.2 , the reaction time of 5h , the reaction temperature is 10 ° C ; acetyl ethylene diamine N , N' - bis - decyl sodium diacetate optimum synthesis conditions : a mixed solution of water and acetone as the solvent , and the intermediate with decanoyl chloride molar ratio was 1:2.1 , reaction time was 5h, the reaction temperature is 10 ° C ; N , N' - bis - ethylenediamine diacetate Sodium lauroyl optimal synthesis conditions : a mixed solution of water and acetone as the solvent , the molar ratio of the intermediate with lauroyl chloride 1:2.2 , the reaction time for 6h, the reaction temperature was 30 ° C . Determined by the surface tension of Gemini surfactants , foaming and foam stability , Krafft point , emulsification and solubilization and compared . The experimental results show that the synthesis of Gemini surfactant surface tension lower than traditional surfactants , synthetic Gemini surfactant cmc values ??about an order of magnitude lower than traditional surfactants , with the growth of the carbon chain , the lower cmc value . Krafft point lower than traditional surfactants , and with the growth of the carbon chain , the Krafft point increase ; emulsifying , foaming and solubilizing are getting better and better as the carbon chain growth .