Abstract
The physical properties of many organic molecules often oscillate when the number of carbons in their aliphatic chains changes from odd to even. This odd-even effect for single-chain surfactants in solution is rarely observed. Here, we report the ability of single-chain surfactants to emulsify a class of non-amphiphilic organic salts, disodium cromoglycate (5'DSCG) oscillates as a function of the odd or even number of the aliphatic carbons. This system provides a water-in-oil-in-water emulsion, in which aqueous droplets of 5'DSCG in liquid crystal phases are coated with single-chain surfactants in a bulk carrying aqueous solution. For both surfactants of CH3(CH2)nOSO3-Na+ and CH3(CH2)nCOO-Na+, the ability to emulsify 5'DSCG molecules in water is stronger for surfactants with an odd number of sp3-hybridized carbon atoms in the aliphatic chains than those with an even number. This observed odd-even effect is consistent with the notion that conventional micelles possess a core of randomly arranged surfactant hydrocarbon tails. However, this water-in-oil-in-water resembles a vesicle system in which the surfactants assemble in a highly ordered structure that separates two aqueous systems. These new self-assembled phases have potential application in the formulation and design of new organic soft materials.
Original language | English (US) |
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Pages (from-to) | 95-99 |
Number of pages | 5 |
Journal | Journal of Colloid And Interface Science |
Volume | 412 |
DOIs | |
State | Published - Dec 15 2013 |
Keywords
- Chromonic liquid crystal
- Disodium cromoglycate (5'DSCG)
- Odd-even effect
- Single-chain surfactants
- Water-in-oil-water emulsion
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Biomaterials
- Surfaces, Coatings and Films
- Colloid and Surface Chemistry