Artículos de revistas
Thin films of carbohydrate based surfactants and carboxymethylcellulose acetate butyrate mixtures: Morphology and thermal behavior
Fecha
2009Registro en:
Materials science and engineering. C, Biomimetic materials, sensors and systems, v.29, n.2, p.420-425, 2009
0928-4931
10.1016/j.msec.2008.08.018
Autor
AMIM JUNIOR, Jorge
KAWANO, Yoshio
PETRI, Denise F. S.
Institución
Resumen
Thin films of mixtures containing carboxymethylcellulose acetate butyrate (CMCAB) and carbohydrate based surfactant, namely, sorbitan monopalmitate (Span 40) or poly(oxyethylene) sorbitan monopalmitate (Tween 40) were spin-coated onto silicon wafers. The effect of surfactant concentration on resulting film morphology and surface toughness Was Studied by atomic force microscopy (AFM). Upon increasing the concentration of Span 40 in the mixture, films became rougher and more heterogeneous, indicating surface enrichment by Span 40 molecules. In the case of mixtures composed by CMCAB and Tween 40, the increase of Tween 40 in the mixture led to smoother and more homogeneous films, indicating compatibility between both components. Differential scanning calorimetry (DSC) revealed that Span 40 and Tween 40 act as plasticizers for CMCAB, leading to dramatic reduction of glass transition temperature of CMCAB, namely, Delta T(g) = -158 degrees C and Delta T(g)=-179 degrees C. respectively. (C) 2008 Elsevier B.V. All rights reserved.