Precise Determination of Percent Cure of Epoxide Polymers and Composites via Fiber-Optic Raman Spectroscopy and Multivariate Analysis

Abstract

A method for real-time determination of the percent cure of epoxies via in situ fiber-optic Raman spectroscopy has been developed. This method utilizes a probe design developed for real-time monitoring of polymer curing and multivariate analysis to interpret the data and determine percent cure. This method was demonstrated to be reliable to ±0.54% of cure in laboratory samples over a 50–99% cure range. A preliminary study measuring cure percentage in an industrial, glass-reinforced composite has been shown to be reliable to ±0.82% in the 40–90% cure range.

Keywords

Fiber-optic Raman Multivariate analysis Principal component analysis

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