含酰胺基团松香基双子表面活性剂的合成与性能

Synthesis and Properties of Rosin-based Gemini Surfactants with Amide Group

以脱氢枞酸为原料,经酰胺化、季铵化等反应步骤合成了3种具有新型结构的双子表面活性剂:1,6-二(3-脱氢枞酰胺-丙基-二甲基溴化铵)己烷、1,8-二(3-脱氢枞酰胺-丙基-二甲基溴化铵)辛烷及1,10-二(3-脱氢枞酰胺-丙基-二甲基溴化铵)癸烷(简称为R-6-R,R-8-R和R-10-R)。通过表面张力法和电导法研究了3种表面活性剂的表面活性,发现此类表面活性剂性质良好:R-6-R,R-8-R及R-10-R的临界胶束浓度(Ccmc)分别为0.41、0.39和0.24 mmol/L,最小分子占据面积(Amin)分别为1.00、1.46和1.72 nm2,疏水链上的酰胺基团促进了表面活性剂在界面的吸附;刚性松香骨架的存在,使该类表面活性剂具有强的稳泡性能和乳化性能,R-6-R,R-8-R及R-10-R的泡沫半衰期分别为1 320、1 200和1 050 min,且浓度为0.3 mmol/L的乳状液静置7 d仍然稳定不分层。

Three novel rosin-based Gemini surfactants, i. e. , 1,6-bis （3-dehydroabietic amide-propyl-dimethyl ammonium bromide） hexane, 1,8-bis （ 3-dehydroabietie amide-propyl-dimethyl ammonium bromide ） octane and 1,10-bis （ 3-Dehydroabietic amide-propyl-dimethyl ammonium bromide） decane （abbreviated to R-6-R, R-8-R and R-10-R）, were synthesized from dehydroabietic acid via reactions of amidation and quaternization. The surface activities of three surfactants were investigated by surface tension and electric conductivity methods. And the resuhs showed that the critical micelle concentrations （ Ccmc ） of R-6-R, R-8-R and R-10-R were 0.41,0.39 and 0.24 mmol/L,and the minimum molecular occupation areas （Amin ） were 1.00, 1.46 and 1.72 nm2 , respectively. The amide groups in the hydrophobic chain promoted the adsorption of surfactants at the interface. The presence of a rigid rosin skeleton made this kind of surfactants have strong foam stability and emulsifying properties. The foam half-lives of R-6-R, R-8-R and R-10-R were 1 320,1 200 and 1 050 min, respectively. And the emulsion remained stable after 7 days when the concentration of surfactant was only 0.3 mmol/L.