Mechano-Spectroscopy of Soft Materials with Atomic Force Microscopy: Comparison with Raman Confocal Microscopy

N. Kulachenkov, M. Petrov, I. Sokolov
Tufts University,
United States

Keywords: AFM, polymeric materials, Raman microscopy, soft materials

Summary:

Here we present the study of methods for identifying various soft materials using atomic force microscopy (AFM). In these methods, an AFM works in imaging sub-resonance tapping Ringing mode, which allows collecting multiple mechanical and physical maps of a sample with nanometer lateral resolution. By combining different maps, one obtains multidimensional images of the sample surface which are specific to each particular material. Having collected sufficient data, one can develop a machine learning method that allows identifying these materials among the unknown ones, .i.e., to perform the spectroscopy. We compare this method with the traditionally used Raman confocal microscopy. The study is done using a mix of polystyrene particles embedded in epoxy. The advantages and challenges of the described mechano-spectroscopy are discussed.