Scanning force microscopy (SFM) has been used to assess the local mechanical properties of fibre-reinforced polymers. Using a sinusoidal displacement modulation (DM) and lock-in technique the method allows to characterize local viscoelastic properties with a high lateral resolution. The simultaneous measurement of the local electrical conductivity is proposed which facilitates the interpretation of the mechanical data. The investigation of cross-sections perpendicular to the axis of carbon fibres embedded in PPS delivers some information about the change in local stiffness within the interfacial region. As a first approach, assuming a single-exponential decrease in local stiffness along a radial line from fibre to polymer we find characteristic decay lengths which are distributed in a range between 20 and 80nm. Further, a modified DM-mode is proposed which is expected to provide a contrast enhancement of the signal which is related to local stiffness. This can be achieved by installing an additional feedback loop which keeps constant the amplitude of dynamic indentation (CDI-mode).
Beyond measuring the topography of surfaces, scanning force microscopy (SFM) has proved to be valuable both for mapping of various materials properties and for modifying surfaces via lithography techniques. Thus, SFM has gained relevance as a surface analysis technique as well as a tool for nanoscale engineering purposes. Different kinds of tip-sample interactions are exploitable, e.g. mechanical, thermal and electrical ones. Owing to its versatility, SFM has found plenty of applications in polymer science. Among others, the examples reported on in this review article encompass issues related to commodity polymers, various polymer-based composites, polymer blends, or ferroelectric polymers. For instance, stiffness imaging is elucidated as a technique for detecting interphases occurring in composites with inorganic fillers. The described applications are mainly related to mechanical and electrical tip-sample interactions. The respective fundamentals are outlined as well as some aspects of the measurement of materials contrasts. The presented techniques of nano-scale modification are a dynamical sort of plowing lithography and electrical poling, both performed by means of SFM-probes.