Dielectric cure monitoring is now a proven methodology. The scheme of using embedded capacitors for practical process-control monitoring of polymerization (cure) of epoxies and other thermosetting plastics has been investigated [1,2,3,4,5,6]. The frequency range over which the effect of cure state on the electrical properties is pronounced varies with material and with cure temperature. Cure monitoring has usually been done at frequencies of the order of 1 Hz to 1 kHz, and sometimes lower. At megahertz and higher frequencies the dielectric constant is expected to vary very little with the cure state. Commercial sensors and instrumentation are currently available [7] for embedded dielectric cure monitoring.
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