Adsorption and aggregation of 2-hydroxyl-propanediyl-α,ω-bis(dimethyldodecyl ammonium bromide) in aqueous solution: Effect of intermolecular hydrogen-bonding

• Published in: Journal of colloid and interface science 2010-11, Vol.351 (2), p.457-465
• Main Authors: Pei, Xiaomei, You, Yi, Zhao, Jianxi, Deng, Yongshu, Li, Erjun, Li, Zhenxiang
• Format: Article
• Language: English
• Subjects: Adsorption; Adsorption and aggregation; Air; Chemistry; Colloidal state and disperse state; Exact sciences and technology; General and physical chemistry; Hydrogen Bonding; Hydroxyl substituted spacer; Intermolecular hydrogen bonding; Micelles; Micelles. Thin films; Molecular Structure; Quaternary Ammonium Compounds - chemical synthesis; Quaternary Ammonium Compounds - chemistry; Solutions; Surface physical chemistry; Surface Properties; Surface-Active Agents - chemical synthesis; Surface-Active Agents - chemistry; Water - chemistry
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2010.07.076

12-3(OH)-12 forms intermolecular hydrogen bonding through the substituted spacers, which in turn strongly affects adsorption and aggregation. [Display omitted] ► The hydroxyl substituted surfactant forms dimers by intermolecular hydrogen bonding. ► Intermolecular hydrogen bonding enhances adsorption and association of the surfactant. ► Intermolecular hydrogen bonding interaction promotes growth of the micelles. ► Hydrogen bonding leads to dissociation of more counterions on the aggregate surfaces. The adsorption and aggregation of 2-hydroxyl-propanediyl-α,ω-bis(dimethyldodecyl ammonium bromide) (abbreviated as 12-3(OH)-12) in aqueous solution have been investigated by equilibrium and dynamic surface tension, surface dilational rheology, conductivity, fluorescence probing, viscosity, zeta potential and dynamic light scattering measurements. The results measured by dynamic surface tension, molar and differential conductivities strongly suggested the formation of dimolecular moieties in dilute systems prior to their adsorption and aggregation, which was attributed to intermolecular hydrogen-bonding between the hydroxyl substituted spacers. This increased the hydrophobicity of the molecular moieties and greatly promoted their adsorption at the air/water interface and association in solution. The intermolecular hydrogen-bonding between the molecules adsorbed at the air/water interface made their arrangement tighter and thus produced lower γ cmc compared with unsubstituted 12-3-12. Moreover, the effect of intermolecular hydrogen bonding promotes growth of 12-3(OH)-12 micelles and leads to dissociation of the counterions on the aggregate surfaces.