Dynamic mechanical analysis thermal aging effects

Dynamic Mechanical Analysis (qv) (DMA) or dynamic thermal mechanical analysis (DTMA) indicate damage in polymers or PMC (34), and aging effects in polymers by a shift in the transition temperature (35). Limitations are the volume of the test chamber or the required specimen shape. 

The general experimental approach used in 2D correlation spectroscopy is based on the detection of dynamic variations of spectroscopic signals induced by an external perturbation (Figure 7.43). Various molecular-level excitations may be induced by electrical, thermal, magnetic, chemical, acoustic, or mechanical stimulations. The effect of perturbation-induced changes in the local molecular environment may be manifested by time-dependent fluctuations of various spectra representing the system. Such transient fluctuations of spectra are referred to as dynamic spectra of the system. Apart from time, other physical variables in a generalised 2D correlation analysis may be temperature, pressure, age, composition, or even concentration. 

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