Effect of Headgroup Chirality in Nanoassemblies. 2. Thermal Behavior of Vitamin C-Based Surfactants

Date

2009

Authors

Lo Nostro, Pierandrea
Ambrosi, Moira
Ninham, Barry
Baglioni, Piero

Journal Title

Journal ISSN

Volume Title

Publisher

American Chemical Society

Abstract

L-Ascorbic and D-isoascorbic acids are epimers, and their alkanoyl-esters are surfactant-like in water. These ascorbic acid derivatives retain the same stereogenic configurations of the parent molecules. That circumstance strongly affects their physicochemical properties, both in the solid and in the dispersed states. The thermal behavior of 6-O-L-ascorbyl-dodecanoate (L-ASC12), of 6-0-D-isoascorbyl-dodecanoate (D-ASC12), and of their mixtures was investigated through DSC, XRD, and FTIR experiments. The results indicate that the mixtures of the two epimers produce two eutectics and a 1:1 molecular compound, both in the pure phase and in the coagel state. From the phase diagram data, the activity coefficients of the different species and the main excess thermodynamic functions can be calculated. The results provide insight into the effects of stereochemistry on their intermolecular interactions.

Description

Keywords

Keywords: Ascorbic acids; Epimers; Excess thermodynamic function; FTIR; Intermolecular interactions; Isoascorbic acid; Molecular compounds; Nano-assemblies; Parent molecules; Physicochemical property; Thermal behaviors; Vitamin C; XRD; Esters; Fourier transform inf

Citation

Source

Journal of Physical Chemistry B

Type

Journal article

Book Title

Entity type

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License Rights

DOI

10.1021/jp9008288

Restricted until

2037-12-31