Product characterization

The following information was submitted by Dr. Harold L. Brown on Thu, 09 Apr 1998:
TherMold Partners, L.P. manufactures Thermally Stimulated Current (TSC) spectrometers. TSC is used to perform thermal analysis of polymeric materials by using natural or induced dipoles to probe their molecular mobility. To analyze a material, a small sample is frozen in the presence of a DC electric field. The electric field polarizes the sample material and lowering the temperature increases relaxation times so that when the field is removed, most of the polarization remains in the sample. Reheating the material permits relaxation of polar entities when the temperature is reached where there is sufficient energy to allow their mobiliy. This molecular level reorientation is detected as depolarization current by a sensitive electrometer thereby generating a spectrum of current versus temperature. Different relaxing entities in the material are resolved by this technique; hydroxyl groups, side chains, etc. contribute to the spectrum at different temperatures. Since this is a driven technique (i.e., we have control over the polarization field which varies our return signal) Tg in lyophilized pharmaceuticals is easy to detect and produce signal to noise ratios of 1000:1 and higher.