物理化学学报 >> 2011, Vol. 27 >> Issue (04): 913-917.doi: 10.3866/PKU.WHXB20110420

软物质 上一篇    下一篇

水杨酸钠对阳离子Gemini表面活性剂水溶液中蠕虫状胶束形成和性质的影响

裴晓梅1, 赵剑曦1, 魏西莲2   

  1. 1. 福州大学化学化工学院, 胶体与界面化学研究所, 福州 350108;
    2. 聊城大学化学化工学院, 山东 聊城 252059
  • 收稿日期:2010-12-06 修回日期:2011-01-26 发布日期:2011-03-29
  • 通讯作者: 赵剑曦, 魏西莲 E-mail:jxzhao.colloid@fzu.edu.cn; weixilian@126.com
  • 基金资助:

    国家自然科学基金(20673021, 20873024, 21073081)资助项目

Effect of Sodium Salicylate on the Formation and Properties of Wormlike Micelles in Aqueous Cationic Gemini Surfactant Solutions

PEI Xiao-Mei1, ZHAO Jian-Xi1, WEI Xi-Lian2   

  1. 1. Institute of Colloid and Interface Chemistry, College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350108, P. R. China;
    2. College of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, Shandong Province, P. R. China
  • Received:2010-12-06 Revised:2011-01-26 Published:2011-03-29
  • Contact: ZHAO Jian-Xi, WEI Xi-Lian E-mail:jxzhao.colloid@fzu.edu.cn; weixilian@126.com
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20673021, 20873024, 21073081).

摘要:

用稳态和震荡剪切实验研究了水杨酸钠(NaSal)对50 mmol·L-1阳离子Gemini表面活性剂2-羟基-(三亚甲基-α,ω-双十二烷基三甲基溴化铵和三亚甲基-α,ω-双十二烷基三甲基溴化铵, 简写为12-3(OH)-12和12-3-12)水溶液中形成蠕虫状胶束及其性质的影响. 在无盐状态下, 50 mmol·L-1的12-3(OH)-12或12-3-12在水溶液中仅形成球状或棒状胶束. NaSal可促进上述两体系胶束的生长, 生成蠕虫状胶束. 比较而言, 12- 3(OH)-12对NaSal更敏感, 可以在低盐浓度下生成蠕虫状胶束. 而且与12-3-12体系相比, 12-3(OH)-12生成了更长的蠕虫状胶束. 这些差别在于12-3(OH)-12体系中存在羟基连接链之间的氢键作用, 这增加了12- 3(OH)-12头基的亲水性, 促进了反离子的解离, 增大的胶束表面电荷密度更强烈地结合水杨酸根反离子, 减小了头基间的静电斥力, 反过来又增强了分子间氢键, 致使 12-3(OH)-12胶束迅速生长.

关键词: 阳离子Gemini表面活性剂, NaSal, 蠕虫状胶束, 流变性质, 分子间氢键

Abstract:

The effect of sodium salicylate (NaSal) on the formation and properties of wormlike micelles in aqueous solutions of 2-hydroxyl-propanediyl-α,ω-bis(dimethyldodecylammonium bromide) (12-3(OH)-12) and propanediyl-α,ω-bis(dimethyldodecylammonium bromide) (12-3-12) at a surfactant concentration of 50 mmol·L-1 was investigated using steady-state and frequency sweep rheological measurements. In the absence of a salt, 12-3(OH)-12 or 12-3-12 only produced spherical or small rod-like micelles at 50 mmol·L-1. The addition of NaSal promoted micellar growth yielding wormlike micelles in both systems. 12-3(OH)-12 showed a more sensitive response to the added NaSal compared with 12-3-12 and formed wormlike micelles at relatively lower salt concentrations. Moreover, the wormlike micelles formed by 12-3(OH)-12 were longer than those formed by 12-3-12, resulting in higher viscosity for the former solution. These were attributed to the hydrogen bonding interactions between the hydroxyl substituted spacers in the 12-3(OH)-12 system, which increased hydration on the aggregate surface and stimulated the dissociation of counterions. The higher charge on the 12-3(OH)-12 micellar surface was strongly associated with Sal-, which led to a tighter packing of the surfactant molecules in the micelles and thus strengthened the intermolecular hydrogen bonding interactions and effectively reinforced the growth of the 12-3(OH)-12 micelles.

Key words: Cationic gemini surfactant, NaSal, Wormlike micelle, Rheological property, Intermolecular hydrogen bond

MSC2000: 

  • O648