Contrasting effect of 1-butanol and 1,4-butanediol on the triggered micellar self-assemblies of C 16 -type cationic surfactants
Contrasting effect of 1-butanol and 1,4-butanediol on the triggered micellar self-assemblies of C 16 -type cationic surfactants
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1-丁醇和1,4-丁二醇对C 16 型阳离子表面活性剂胶束自组装的影响对比
DOI：
10.1039/d1cp01666k
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发表时间：
2021
影响因子：
3.3
通讯作者：
Bahadur, Pratap
中科院分区：
文献类型：
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作者：
Kumar, Vinod;Verma, Rajni;Satodia, Dwarkesh;Ray, Debes;Kuperkar, Ketan;Aswal, Vinod Kumar;Mitchell-Koch, Katie R.;Bahadur, Pratap
研究了三种具有不同极性头基和相同碳烷基链的季铵盐基C16型阳离子表面活性剂在水溶液中的自组装，用表面张力法、二维核欧弗豪泽增强光谱（2D-NOESY）和小角中子散射（SANS）技术研究了溴化十六烷基吡啶（CPB）、甲苯磺酸十六烷基三甲基铵（CTAT）和溴化十六烷基三苯基膦（CTPPB）在正丁醇（BuOH）和1，4-丁二醇（BTD）存在下的反应。在303.15 K的吸附参数和胶束特性的评估清楚地表明，BuOH促进混合胶束的形成，而BTD干扰胶束化现象。SANS数据拟合使用椭球体（由Hayter和Penfold使用Ornstein-Zernike方程和平均球近似）和蠕虫状胶束模型提供了一个洞察胶束的大小/形状和聚集数（纳格）在检查系统。评价的描述符提出了一个明确的指示，在阳离子胶束的形态转变诱导的两种醇的加入。我们还提供了一个调查可接受的分子相互作用的胶束形态的差异，使用非侵入性的2D-NOESY技术和分子建模。从计算模拟阐明的实验观察增加了新奇性这项工作。考虑到三种阳离子表面活性剂的结构复杂性，采用分子动力学（MD）方法对CPB胶束在醇类水溶液中的溶解和结构转变过程进行了模拟，并对体系的临界堆积参数（PP）进行了补充.
The self-assembly in aqueous solutions of three quaternary salt-based C16-type cationic surfactants with different polar head groups and identical carbon alkyl chain viz., cetylpyridinium bromide (CPB), cetyltrimethylammonium tosylate (CTAT), and cetyltriphenylphosphonium bromide (CTPPB) in the presence of 1-butanol (BuOH) and 1,4-butanediol (BTD) was investigated using tensiometry, 2D-nuclear Overhauser enhancement spectroscopy (2D-NOESY) and small angle neutron scattering (SANS) techniques. The adsorption parameters and micellar characteristics evaluated at 303.15 K distinctly showed that BuOH promotes the mixed micelle formation while BTD interfered with the micellization phenomenon. The SANS data fitted using an ellipsoid (as derived by Hayter and Penfold using the Ornstein-Zernike equation and the mean spherical approximation) and wormlike micellar models offered an insight into the micelle size/shape and aggregation number (Nagg) in the examined systems. The evaluated descriptors presented a clear indication of the morphology transition in cationic micelles as induced by the addition of the two alcohols. We also offer an investigation into the acceptable molecular interactions governing the differences in micelle morphologies, using the non-invasive 2D-NOESY technique and molecular modeling. The experimental observations elucidated from computational simulation add novelty to this work. Giving an account to the structural complexity in the three cationic surfactants, the molecular dynamics (MD) simulation was performed for CPB micelles in an aqueous solution of alcohols that highlighted the micelle solvation and structural transition, which is further complemented in terms of critical packing parameter (PP) for the examined systems.