Spatio-chemical characterization of a polymer blend by magnetic resonance force microscopy

Magnetic resonance force microscopy (MRFM) is a promising method to obtain magnetic resonance images with nanometer resolution. One of the factors currently limiting its application to compounds with strong and possibly time-dependent dipolar couplings is the imperfect efficiency of the adiabatic inversion sweeps and the concomitant loss in the signal to noise ratio. We describe significant improvements to previous MRFM excitation schemes. Applying these schemes to a polymer blend of 80% PEEK and 20% PTFE allowed acquiring full-volume two-dimensional (2D) spatial images (with Hadamard multiplexing) of both the (1)H and (19)F-rich phases with a 6-fold enhancement in the SNR.