Smart Surfaces of Biobased Materials . III . Surface segregation in Cellulose Ester Films
نویسنده
چکیده
The surface of solvent cast films of blends of cellulose propionate and fluorine (F)-containing cellulose derivatives was examined. Static wetting force measurements of blends showed a sharp decline in wetting force at low blend concentrations of the Fspecies. This indicated enrichment of the F-containing derivative at the surface. X-ray photoelectron spectroscopy (XPS) of blends revealed a surface concentration of F higher than by blend composition, verifying surface segregation. The extent of surface segregation was a function of the nature of the F-component and its blend concentration. Angle dependent XPS measurements revealed an F-gradient with sampling depth with the highest F-content found in the top 30 nm-layer. Limited surface heterogeneity, depending on the type of F-derivative was detected by phase-image atomic force microscopy.
منابع مشابه
Smart surfaces of biobased materials: IV. Dynamic surface effects in films of F-containing cellulose esters
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