| Abstract
| - The kinetics of curing of an epoxy resin by amine wasstudied using a near-infrared (NIR) multispectral imagingspectrometer. This imaging spectrometer is capable ofsensitively and rapidly recording NIR spectral images ofa sample because it was constructed with an acousto-optictunable filter and an InGaAs focal plane array NIR camera.The high sensitivity and fast scanning ability of thespectrometer make it suitable for kinetic determinationof fast reactions. Additionally, it has features that conventional NIR spectrometers cannot offer, namely, itsability to provide kinetic information at different positionswithin a sample. Furthermore, the high spatial resolutionand sensitivity of the InGaAs camera make it possible todetermine the kinetics from data collected by a single pixelin the camera. The kinetics of curing of epoxy by amine,determined by this multispectral imaging instrument,show that the reaction rates within the sample are veryinhomogeneous. Because of this kinetic inhomogeneity,differences in the degrees of cure at different positionswithin the sample can be as high as 37% when data fromonly a single pixel were used for calculation. The inhomogeneity was not be observed if an average of a largenumber of pixels were used.
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