Nanoindentation is a powerful technique for characterizing small volumes of material for the mechanical properties of viscoelasticity, including storage modulus, loss modulus, and tan delta. The primary advantage of this technique for polymers is the ability to resolve these properties with spatial resolutions on the micro- and nano-scales.
In this report, details of the contact dynamic mechanical analysis (CDMA) technique using a nanoindenter platform are covered and a comparison of these results to traditional dynamic mechanical analysis (DMA) results are made.
The primary advantages of the CDMA technique are the ability to evaluate gradients in laminate layers of rubber compounds and the ability to map material degradation zones. In addition, sample preparation methods for tire cross-sections are described.
The combination of these powerful techniques allows tire samples to be tested in cross-section without the difficulty of dissecting the individual laminate layers. CDMA provides a new measurement technique for obtaining viscoelastic properties on volumes previously considered too small for characterization through the dissection technique.