Real-time in situ monitoring of the thermal cure of a bisphenol cyanate: A view toward intelligent processing

A dispersive fiber‐optic Raman spectrometer was used to remotely monitor, in real‐time, the local temperature and the extent of reaction of a commercial cyanate ester polymer (AroCy L‐10). The local temperature was determined by solving the Boltzmann relation governing the intensity ratio of the Raman Stokes and anti‐Stokes scattering of a reference mode which does not vary with the reaction chemistry. The extent of the reaction can be monitored using either individual peaks assciated with the reactant or product or by using the entire spectrum and principal component multivariate calibration. The use of principal component analysis has distinct advantages over the single‐peak method. © 1996 John Wiley & Sons, Inc.