In-Situ Monitoring Of Resin Curing Process Based On Interdigital Impedance Sensors

The online monitoring of resin curing process is described in the presented article. There exists several monitoring technique useful for resin curing monitoring and consequently for the curing technology improving, at the present. The advantage of the described monitoring system and monitoring method is in the using a unique sensors directly inserted into the tested resin or technology part which allows observing the resin characteristics as well as the local temperature directly at the sensor area. The data acquisition is processed by the in-house developed portable curing monitoring device and wirelessly transfered to the PC for further analysis. The study describes the experimental work of using the monitoring system and sensors and also the curing process of resins and composites using electrical impedance magnitude.There are identified and described the typical glass transition temperature stages of resin as lowest viscosity, gel point and vitrification of the cured system. These points are necessary to know online for curing process control.The monitoring system could be useful for pure resin diagnostics as well as for the fibre reinforced composites even for fibre reinforced composites using conductive fibres (for example carbon fibres). The developed system is more sensitive than RLC method.