Gemini表面活性剂/C12En混合体系的界面吸附、扩张粘弹与泡沫稳定性(英文)  

Interfacial Adsorption,Dilational Visco-Elasticity and Foam Stability in a Mixed System of Gemini Surfactant/C_(12)E_n

作　　者：宋冰蕾[1] 翟兆兰 赵剑曦[2] 孙国静[2] 

机构地区：[1]江南大学化学与材料工程学院,食品胶体与生物技术教育部重点实验室,江苏无锡214122 [2]福州大学化学化工学院胶体与界面化学研究所,福州350108

出　　处：《物理化学学报》2015年第12期2324-2331,共8页Acta Physico-Chimica Sinica

基　　金：supported by the National Natural Science Foundation of China(21473032,21273040)~~

摘　　要：用表面张力法研究了阳离子gemini表面活性剂乙基-1,2-双(十二烷基二甲基溴化铵)(简写为12-2-12)和非离子表面活性剂十二烷基聚氧乙烯醚(C_(12)E_n,其中n=4,10,23)混合体系在气液界面上的吸附行为;用扩张流变技术研究了吸附膜的扩张粘弹行为,实验数据用Lucassen-van den Tempel(LVT)模型进行拟合并根据模型得到了极限弹性值.最后研究了混合体系的泡沫行为,用泡沫塌陷到初始高度一半所对应的时间(t_(1/2))来表征泡沫的稳定性.结果表明,所有的非离子表面活性剂C_(12)E_n均与12-2-12产生了吸引作用.在12-2-12浓度相同的情况下,混合吸附层中吸附分子的最小分子占据面积的顺序为12-2-12/C_(12)E_(23)>12-2-12/C_(12)E_(10)>12-2-12/C_(12)E_4,而极限弹性的顺序为ε_(0,fit)(12-2-12/C_(12)E_4)>ε_(0,fit)(12-2-12/C_(12)E_(10))>ε_(0,fit)(12-2-12/C_(12)E_(23)).与单组分12-2-12形成的吸附膜相比,只有12-2-12/C_(12)E_4形成更加紧密的结构.具有较小亲水头基的非离子表面活性剂C_(12)E_4的加入可增强12-2-12吸附膜的弹性,进而增强了对应体系泡沫的稳定性.The mixed adsorption of a cationic gemini surfactant, ethanediyl-l,2-bis（dodecyldimethylammonium bromide） 12-2-12）, and a nonionic surfactant, polyoxyethylene mono-dodecyl ether （C12E,, where n = 4, 10, 23） at the air/water interface was studied using surface tension measurements. The dilational viscoelastic properties of the films that formed at the air/water interface were examined using an interracial theology technique that was described using the Lucassen-van den Tempel （LVT） model. The values of the limit elasticity were fitted accordingly. Foams were generated by the mixed surfactant aqueous solutions and the stability of foams determined using the half-life. C12En exhibited attractive interactions towards 12-2-12 within the adsorption films. The average minimum area （Amen） of the adsorbed molecules decreased in the order： 12-2-12/C12E23 〉 12-2-12/C12E10 〉 12-2-12/C12E4, while the limit elasticity decreased in the reverse order： ε0,fit（1 2-2-12/012E4） 〉 ε0,fit（12-2-12/C12E10） 〉 ε0,fit（12-2-12/C12E23） at a comparable concentration of the surfactant in the bulk. Compared with the film adsorbed by 12-2-12 alone,only 12-2-12/C12E4 form had denser structure. Thus, by adding the nonionic component C12E4, which contained a small hydrophilic head group, the interfacial elasticity of the 12-2-12 film increased significantly and the stability of the corresponding foams was effectively enhanced.

关 键 词：混合吸附 阳离子gemini表面活性剂 非离子传统表面活性剂 界面弹性 泡沫稳定性 

分 类 号：O647.2[理学—物理化学]