The analyser delivers high-quality results for modulus values and is in many respects very different from conventional DMA instruments in that it measures both force and displacement.
An automatic switch mode controls the measurement and automatically changes from force-controlled to displacement-controlled.
This is particularly important for stiff samples (force-controlled analysis) that become soft when they are heated (displacement-controlled).
The frequency range of the oscillating stress has been extended to the 1000Hz range. In shear mode, six frequency decades are available.
The region above 1Hz is particularly important because it means that the measuring times can be kept to a minimum.
Special care was taken to develop a system that allows precise temperature control and adjustment.
For this, an additional sensor was introduced, which measures sample temperature very close to the sample. This permits calibrations that are based on the melting points of pure substances.
Moreover, the temperature sensor also allows thermal effects to be simultaneously measured by SDTA – useful for monitoring curing reactions.
METTLER TOLEDO introduced a sample holder system in the DMA/SDTA, which enables sample preparation and mounting to take place externally, for quick insertion inside the instrument.
The concept also allows the user to change from one deformation mode to another without performing an adjustment; users can also prepare samples unhindered while a measurement is in progress.