| Abstract: | Emission Fourier transform infrared (FTIR) spectroscopy has been found to be a suitable technique for monitoring the thermal cure of thin films of photocatalysed dicyanate ester resins. The kinetics of the polymerization of a commercial cyanate ester resin (AroCy RTX‐366) catalysed by an organometallic compound, tricarbonyl cyclopentadienyl manganese (CpMn(CO)3), have been determined using this technique and the results compared with those obtained from transmission FTIR. The trimerization reaction rate of the resin is found to have a first order dependence upon both the cyanate fraction and the active catalyst concentration until diffusion control occurs. To elucidate the mechanism, a system with premade catalyst, which was the photoreaction product of the resin and the organometallic compound, has also been studied. The activation energy for this system is 91 ± 10 kJ mol−1 compared to 72 ± 8 kJ mol−1 for the directly irradiated system. This may arise from different distributions of three photoproducts identified as complexes between manganese and the cyanate ester. © 2000 Society of Chemical Industry |
