Biomedical Engineering Reference
In-Depth Information
4
Tools to Probe Nanoscale Surface
Phenomena in Cellulose Thin Films:
Applications in the Area
of Adsorption and Friction
Junlong Song, Yan Li, Juan P. Hinestroza and Orlando J. Rojas
4.1
Introduction
Surfaces and interfaces play important roles in defining material interactions. Several
developments in science and technology highlight the importance of interfaces in appli-
cations involving material functionalization, coatings, colloidal stability, etc. (Karim and
Kumar 2000). In many cases, the interfacial properties are more relevant than the nature
and composition of the bulk phases and ultimately define the molecular behavior of the
system.
The 'thickness' of a boundary between two phases, if possible to define, is expected to
be extremely narrow. The interface between (bio)polymers or that for a polymer-coated
substrate and the surrounding medium typically entails a 'soft' layer with molecular or
nanoscale dimensions. The use of adsorbed polymers and surfactants to modify solid
surfaces offers unique possibilities to alter or regulate their properties, including surface
energy, molecular assembly and composition, among others. In order to effectively
or permanently modify the interfacial properties the adsorbing material (or adsorbate)
has to bind to some degree or extent to the respective surface. Therefore, adsorption is
fundamental in many important applications, particularly in the general fields of adhesion,
colloidal stabilization, friction, and heterogeneous reactions.
Search WWH ::




Custom Search