INQUISUR   21779
INSTITUTO DE QUIMICA DEL SUR
Unidad Ejecutora - UE
artículos
Título:
The interaction between water vapor and chitosan II: computational study
Autor/es:
M.L. FERREIRA; V.I. PEDRONI; G.A. ALIMENTI; M.E. GSCHAIDER; P.C. SCHULZ
Revista:
Colloid Surf A: Physicochem. Aspects
Referencias:
Año: 2008 vol. 315 p. 241 - 249
ISSN:
0927-7757
Resumen:
step of adsorption of water on chitosan, taking into account water clustering phenomena upon adsorption, the water structure, and thetemperature on water structure (i.e., the presence of dimers or monomers). The degree of acetylation (DA) influences markedly the fiwater vapor adsorption on chitosan. Modeling results on the first step of adsorption were analyzed taking into account the ratio water dimonomer and the species predominant as a function of ambient conditions (i.e., relative humidity (RH) and temperature (T)). Fromthe exppoint of view, the ratio of water dimer/water monomer has a different effect on chitosans depending on its DA and adsorption temperfound that the adsorption of water monomer on a model of hydrated chitosan is favoured in almost −84 kJmol−1of steric energy, wadsorption on dehydrated chitosan by only −21 kJmol−1. The water–chitosan surface distance found in this work was 0.2 nm, whilst thevalues are between 0.245 nm and 0.309 nm for the hydrated chitosan crystalline structure. It was evident that at least two tetramers are rrepresent the surface of chitosan.© 2007 Elsevier B.V. All rights reserved.