Scanning probe microscopy of heterogeneous polymers

Adhesion, elastic and viscoelastic properties are characteristic parameters of materials. These mechanical properties of polymers show a strong depend ence on the manufacturing process, the molecular weight, the temperature an d the environment. It would be desirable to have tools for characterization of small samples. The scanning force microscope seems to be an ideal instr ument when working towards this goal. The nanometer sized probe in contact with the sample surface can be used to measure a variety of surface propert ies, ranging from friction to adhesion. The measurements could be truly qua ntitative if one knew exactly the shape of the tip and the strength and dis tance dependence of the interaction forces. It is shown in this paper how t he measurement modes of a scanning force microscope can be tailored to obta in quantitative data. We discuss the advantages and disadvantages of the pu lsed force mode investigations using homogeneous and heterogeneous polymer samples as test objects. (C) 1999 Elsevier Science B.V. All rights reserved .