Instrumentation for wide frequency range measurements of epoxy resin during microwave curing

A new instrumentation system for measuring wide frequency band complex perm ittivity (1 MHz-2 GHz) during the microwave curing process has been develop ed using an original system coupled with coaxial discontinuity. The instrum entation operates through the automatic commutation of the wide frequency b and cell on a power supply or a probe supply. This system allows the use of different heating frequencies (215 MHz, 434 MHz, or 2.45 GHz) with the sam e cell. This instrumentation has been used to study microwave curing compar ed with conventional heating, but it can also be applied to the use of micr owaves in chemical processes or to study the biological effects of microwav es. (C) 2000 American Institute of Physics. [S0034-6748(00)02904-X].