Hydrogels: Characterization at the Micro- and Nano-scale by SEM and SFM

Hydrogels are water swollen, crosslinked polymeric structures, produced by the simple reaction of one or more monomers or by association of bonds such as hydrogen bonds and strong van der Waals interactions between chains. A large amount of today's research is focused on probably the most interesting among them, the so-called "smart" hydrogels. A representative of this class of hydrogels is a polymer system with a defined phase transition capable to abruptly swell to many times its original size or to collapse into a compact mass when stimulated externally [1]. The following studies demonstrate some of the advantages and the strength of the complementary employment of Field Emission Scanning Electron Microscopy (FESEM) and Scanning Force Microscopy (SFM) in the characterization of hydrogels: Highly resolved structural information by FESEM are complemented by SFM using micrometer-sized probing spheres for quantitative measurements of the local micromechanical.