Modulator - PM-100
The application of step-scan FT-IR spectrometry to rheo-optical studies of polymers has
attracted considerable interest from the polymer physics and engineering communities.
Several studies (see, for example, Bibliography and references in those publications) have
measured the time dependence of spectral changes in polymer samples during modulated
strain, with the use of custom-built instrumentation. The Polymer Modulator
provides a convenient, commercially-available tool for combining spectroscopic
measurements with rheological perturbation. The system consists of two components, an
electromechanical head, where the sample is mounted, and an electronic power unit. The
head is connected to the electronic power unit by a cable. The power unit contains the
necessary circuits to amplify an input signal to drive the piezoelectric transducer, as
well as amplifiers and signal conditioning for the stress and strain transducers.
The drive waveform for the MAT Polymer Modulator can be digitally produced so
that the short- and long-term frequency stability are governed by quartz clock. Because
the drive mechanism is piezoelectric, the applied waveform is completely programmable,
with full response to component frequencies up to 70 Hz. The device is usable over more
than two decades of frequency, from below 0.07 to 70 Hz, and is fully instrumented with
stress and strain sensors. The frame of the device is fabricated from 303 stainless steel
to minimize thermal expansion. The frame has threaded holes for suspending the device, if
necessary to avoid coupling vibrations to the spectrometer. The power unit may be mounted
in a standard electronic rack. Optional temperature control for the range of -30 to 70 °C
is also available.