MICROMECHANICAL PROPERTIES OF ELASTIC POLYMERIC MATERIALS AS PROBED BY SCANNING FORCE MICROSCOPY

Scanning force microscopy (SFM) was used for probing micromechanical p roperties of compliant polymeric materials. Classic models of elastic contacts, Sneddon's, Hertzian, and JKR, were tested for various indent ation depths and for a variety of polymeric materials. We selected ext remely compliant polyisoprene rubbers (Young's modulus, E = 1-3 MPa), elastic polyurethanes (E = 5-50 MPa), and hard surfaces of polystyrene (PS) and polyvinylchloride (PVC) (E = 1-5 GPa). Both Sneddon's and He rtzian elastic models gave consistent and reliable results in the rang e of indentation depths up to 200 nm which are close to JKR solution. Close correlation is observed between absolute values of elastic modul i determined by SFM and known values for bulk materials.