Thermal scanning dielectric instrumentation-the PL-dielectric thermal analyser

Discusses the development of a wide range temperature system which is capable of acquiring data during continuous thermal scanning in addition to working at discrete temperatures. Because of interest in polymeric and related materials, the instrumentation has been designed around the frequency range 20 Hz to 100 kHz and temperature range from -150°C to +500°C. The authors call this instrument a Dielectric Thermal Analyser (DETA). The wide temperature range allows all major molecular motion changes (relaxation) to be studied in polymers. Temperature is the major variable in this respect and frequency the minor one. Thus, only a single relaxation process can be covered by one technique at one temperature, whereas five or six relaxation processes might be observed during a single frequency wide range temperature scan. The ability to vary temperature and frequency essentially simultaneously under computer control adds greatly to the power of the technique