title: Symmetric and asymmetric bolaamphiphiles from ascorbic acid.
abstract: The properties of novel bolaamphiphiles that carry epimers of vitamin C (L-ascorbic acid and/or D-isoascorbic acid) as hydrophilic head groups, and an interconnecting aliphatic C(12) chain (DD, DL, and LL) were investigated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), small-angle X-ray scattering (SAXS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) in the solid state (anhydrous powders) and in aqueous dispersions as a function of the surfactant concentration. Upon heating, the aqueous dispersions undergo a phase transition from a hydrated semicrystalline "coagel" to a micellar phase. The results suggest that the headgroup chirality determines the formation of either inter- or intramolecular hydrogen bonds between the polar heads, which affect the phase behavior and structural properties of the nanoassemblies produced by these surfactants in water dispersions. The DSC data of aqueous dispersions were analyzed to obtain the size distribution of the pores in the coagel state.
authors: Ipf Leibniz-Institut für Polymerforschung Dresden e.V., 01069 Dresden, Germany.
authors: Christian
authors: C
authors: Dolle
authors: Pietro
authors: P
authors: Magrone
authors: Sergio
authors: S
authors: Riva
authors: Moira
authors: M
authors: Ambrosi
authors: Emiliano
authors: E
authors: Fratini
authors: Niccolò
authors: N
authors: Peruzzi
authors: Pierandrea
authors: P
authors: Lo Nostro
mesh_terms: D001205:Ascorbic Acid / Q000737:chemistry*; D005663:Furans / Q000737:chemistry*; D006860:Hydrogen Bonding; D011728:Pyridones / Q000737:chemistry*; D013501:Surface-Active Agents / Q000737:chemistry; D013696:Temperature; D013816:Thermodynamics
chemical_list: D005663:Furans; D011728:Pyridones; D013501:Surface-Active Agents; C543575:bolaamphiphile; C005056:isoascorbic acid; D001205:Ascorbic Acid