Comb-Like Ionic Complexes of Cationic Surfactants with Bacterial Poly(γ-glutamic acid) of Racemic Composition
✍ Scribed by Monserrat García-Alvarez; José Alvarez; Abdelilah Alla; Antxon Martínez de Ilarduya; Concepción Herranz; Sebastián Muñoz-Guerra
- Publisher
- John Wiley and Sons
- Year
- 2005
- Tongue
- English
- Weight
- 191 KB
- Volume
- 5
- Category
- Article
- ISSN
- 1616-5187
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
Summary: Comb‐like ionic complexes, __n__ATMA · PG(DL)GA, were prepared from microbial poly(γ‐glutamic acid), with a nearly racemic configuration, and alkyltrimethylammoniun bromides, with linear alkyl chains containing an even number of carbon atoms, n, ranging from 12 to 22. The complexes had a nearly stoichiometric composition, displayed thermal stability up to temperatures above 200 °C and were insoluble in water but soluble in organic solvents. In the solid state, they were arranged in a regularly layered structure with the alkyl side chain crystallized for n ≥ 18. Heating above melting entailed a contraction in the interlayer distance which varied from 1 to 10% depending on the value of n. Comparison with data reported on similar complexes obtained from nearly enantiomerically pure poly(γ‐glutamic acid) revealed an overall behavior very similar for the two series but with specific significant differences concerning side chain crystallinity and dimensional response to temperature.
image