热响应性阴阳离子表面活性剂混合体系囊泡的构筑与稳定性调控  

Construction and regulation of thermo-responsive vesicular solution in catanionic surfactant systems

作　　者：纪秀玲 王英雄[3] 范雅珣[1] 王毅琳[1] Xiuling Ji;Yingxiong Wang;Yaxun Fan;Yilin Wang(Key Laboratory of Colloid,Interface and Chemical Thermodynamics,Institute of Chemistry,Chinese Academy of Sciences,Beijing 100190,China;Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China;Institute of Coal Chemistry,Chinese Academy of Sciences,Taiyuan 030001,China)

机构地区：[1]中国科学院化学研究所,胶体界面与化学热力学实验室,北京100190 [2]中国科学院过程工程研究所,北京100190 [3]中国科学院山西煤炭化学研究所,太原030001

出　　处：《中国科学：化学》2022年第5期678-688,共11页SCIENTIA SINICA Chimica

基　　金：国家自然科学基金(编号:21633002)资助项目。

摘　　要：制备稳定的表面活性剂囊泡是进一步发展囊泡技术的关键.本工作制备了两种酰胺基分别在疏水链和连接基团的阳离子Gemini表面活性剂(C_(12)A-C_(2)-AC_(2)和C_(2)-AC_(12)A-C_(2))与阴离子谷氨酸表面活性剂(C_(2)Glu)混合体系囊泡,系统研究了酰胺基位置和羧基间氢键对囊泡形成与热稳定性的影响.结果表明,位于疏水链上的酰胺基通过氢键可有效促进表面活性剂混合体系囊泡形成和热稳定性,C_(12)A-C_(2)-AC_(2)&C_(2)Glu囊泡在升高温度过程中保持蓝色乳光不变,但对于酰胺基位于连接基团上的C_(2)-AC_(12)A-C_(2)&C_(2)Glu囊泡溶液,其蓝色乳光随温度升高逐渐转变为乳白色或出现沉淀,降低温度溶液再次恢复蓝色乳光.含有两个羧基的C_(2)Glu的带电量及分子间氢键随p H此消彼长,p H 5.0时C_(2)Glu羧基形成的分子间氢键促进了C_(12)A-C_(2)-AC_(2)&C_(2)Glu和C_(2)-AC_(12)A-C_(2)&C_(2)Glu囊泡的形成和热稳定性,在升温过程中混合体系囊泡溶液均没有产生沉淀,而p H 10.0时这两个体系形成的囊泡溶液随温度升高分别出现蓝色乳光加深和沉淀现象.这类具有温度响应性、高效形成囊泡的体系具有重要的实际应用价值.The aggregation behaviors in the binary systems of cationic Gemini surfactants with amide groups in hydrophobic chains(C_(12)A-C_(2)-AC_(2))or spacer group(C_(2)-AC_(12)A-C_(2))and anionic amino acid surfactant N-dodecanoylglutamic acid(C_(2)Glu)have been studied at two different p H values by adjusting the mixing ratio and temperature.The catanionic surfactant systems at p H 5.0 and 10.0 formed spherical micelles and vesicles at 25℃by varying the mixing ratio,respectively.Upon increasing the temperature,the different temperature responsivenesses were realized in four vesicular solutions of catanionic surfactant systems.At p H 5.0 and 10.0,the vesicles formed in C_(12)A-C_(2)-AC_(2)&C_(2)Glu system were stable and maintained a bluish hue,while the vesicles in C_(2)-AC_(12)A-C_(2)&C_(2)Glu system tended to form the larger aggregates,accompanied by the change in solution from bluish to milky,or even precipitation with increasing temperature.Besides,the intermolecular hydrogen bonding of C_(2)Glu containing two carboxyl groups played an important role in vesicle formation and thermal stability.For C_(12)A-C_(2)-AC_(2)&C_(2)Glu and C_(2)-AC_(12)A-C_(2)&C_(2)Glu systems at p H 5.0,the hydrogen bonding of carboxyl groups in C_(2)Glu promoted the vesicle formation and thermal stability.In contrast,at p H 10.0,the carboxyl groups did not form hydrogen bonds and the vesicular solutions of C_(12)A-C_(2)-AC_(2)&C_(2)Glu and C_(2)-AC_(12)A-C_(2)&C_(2)Glu systems underwent dark blue or the transition from bluish to milky to precipitation,respectively.Moreover,these transition processes were thermally reversible.These thermo-responsive vesicular solutions can be elucidated on the basis of the temperature-induced variations in the strength of hydrogen bonds of the headgroups.The results suggested that the location of amide groups and hydrogen bonding between carboxyl groups could affect the formation and thermal stability of vesicular solutions.

关 键 词：带有酰胺基团的阳离子Gemini表面活性剂 阴离子谷氨酸表面活性剂 囊泡 氢键 温度 

分 类 号：TQ423.12[化学工程]