ABSTRACT The storage modulus and loss modulus of blends of polypropylene/polystyrene and polyethylene/polystyrene have been mapped quantitatively with contact resonance atomic force microscopy. Contact resonance spectra were collected in Dual AC Resonance Tracking (DART) mode, in which the phase and amplitude are monitored at two discrete frequencies, resulting in maps of contact resonance frequency and quality factor. These data are then used to compute quantitative storage and loss moduli parameters for the materials being imaged. Computed storage moduli compare favorably with the high-frequency, time–temperature, superposed, low-frequency dynamic mechanical analyzer (DMA) values, whereas the computed loss moduli exhibited greater uncertainty in comparison with the bulk DMA values.