Nanostructurated Complexes of Poly(,L-malate) and Cationic Surfactants: Synthesis, Characteriz
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- 作者：José ; A. Portilla-Arias ; Montserrat Garcí ; a-Alvarez ; Antxon Martí ; nez de Ilarduya ; Eggerhard Holler ; and Sebastiá ; n Muñ ; oz-Guerra
- 刊名：Biomacromolecules
- 出版年：2006
- 出版时间：January 2006
- 年：2006
- 卷：7
- 期：1
- 页码：161 - 170
- 全文大小：756K
- 年卷期：v.7,no.1(January 2006)
- ISSN：1526-4602
文摘
Ionic complexes of microbially produced poly(
,L-malic acid) and alkyltrimethylammonium surfactants with linearalkyl chains containing even numbers of carbon atoms from 14 up to 22, were investigated. Complexes with astoichiometric or nearly stoichiometric composition were prepared by precipitation from equimolar mixtures ofaqueous solutions of the two components. All complexes were found to adopt supramolecular stratified structuresmade of alternating layers of poly(,L-malate) and surfactant with a periodicity on the length scale of 3-5 nm,which increased proportionally to the length of the polymethylene chain. In these complexes, alkyl side chainswith more than 16 carbon atoms were partially crystallized showing reversible melting at temperatures between40 and 70 
C. After melting, a smectic LC phase that isotropicized at ~100 C was observed for all of thecomplexes. Conformational and dimensional changes taking place in the complexes by effect of heating wereanalyzed by 13C CP-MAS NMR and powder X-ray diffraction.
,L-malic acid) and alkyltrimethylammonium surfactants with linearalkyl chains containing even numbers of carbon atoms from 14 up to 22, were investigated. Complexes with astoichiometric or nearly stoichiometric composition were prepared by precipitation from equimolar mixtures ofaqueous solutions of the two components. All complexes were found to adopt supramolecular stratified structuresmade of alternating layers of poly(,L-malate) and surfactant with a periodicity on the length scale of 3-5 nm,which increased proportionally to the length of the polymethylene chain. In these complexes, alkyl side chainswith more than 16 carbon atoms were partially crystallized showing reversible melting at temperatures between40 and 70 C. After melting, a smectic LC phase that isotropicized at ~100 C was observed for all of thecomplexes. Conformational and dimensional changes taking place in the complexes by effect of heating wereanalyzed by 13C CP-MAS NMR and powder X-ray diffraction.