Quantitative control of RTM6 epoxy resin polymerisation by optical index determination

RTM6 epoxy resin curing is usually characterized by the polymerisation degree. We report in this paper on a refractive index measurement technique applied on an experimental mould to control, quantitatively and in situ, the industrial RTM process. For the first time, we determined simultaneously the thermo-optical coefficient, the refractive index evolution, the specific volume and the polymerisation degree of the resin. The calculation of a “polymerisation degree optical coefficient” led to a quantification of the RTM6 epoxy resin polymerisation process. This calibration coefficient is very useful to perform a real time industrial process control. Furthermore, the optoelectronic system is connected to a data processing unit and is easy to use in an industrial environment.