Dynamic atomic force microscopy analysis of polymer materials: Beyond imaging their surface morphology

International audienceDynamic atomic force microscopy is known for its ability to image soft materials without inducing severe damage. The understanding of the origin of the image contrast is not obvious and constitutes an important subject of debate. Here, we propose a straightforward method, based on the analysis of approach-retract curves, which provides an unambiguous quantitative measurement of the local mechanical response and/or topographic contribution(s), depending on the studied sample. From the recorded data, we show that it is possible to determine the different contributions and, therefore, go beyond the morphological aspects. This approach is illustrated here on a thermoplastic elastomer block copolymer, used as a model system presenting phase-separated nanodomains characterized by specific mechanical properties. The extension of the technique to other polymer systems, such as polymer blends, polymer nanocomposites, and conjugated materials, is also discussed