1 research outputs found
Surface Morphology of Vapor-Deposited Chitosan: Evidence of Solid-State Dewetting during the Formation of Biopolymer Films
Chitosan
is a useful and versatile biopolymer with several industrial
and biological applications. Whereas its physical and physicochemical
bulk properties have been explored quite intensively in the past,
there is a lack of studies regarding the morphology and growth mechanisms
of thin films of this biopolymer. Of particular interest for applications
in bionanotechnology are ultrathin films with thicknesses under 500
Ã…. Here, we present a study of thin chitosan films prepared in
a dry process using physical vapor deposition and <i>in situ</i> ellipsometric monitoring. The prepared films were analyzed with
atomic force microscopy in order to correlate surface morphology with
evaporation parameters. We find that the surface morphology of our
final thin films depends on both the optical thickness, i.e., measured
with ellipsometry, and the deposition rate. Our work shows that ultrathin
biopolymer films can undergo dewetting during film formation, even
in the absence of solvents and thermal annealing