The Effects of Phosphotungstic Heteropoly Acid on Degradation Behaviour of Hardened Epoxide Polymers in Near-Critical Water

This paper aims to study the catalytic effects of phosphotungstic acid on the degradation behaviour of E-51/DDM and E-51/MeTHPA epoxy resins. The results show that phosphotungstic acid promotes the decomposition of E-51/DDM and E-51/MeTHPA in different degree. The decomposition rate of E-51/MeTHPA is relatively higher. According to the GC-MS results, the composition of products when phosphotungstic acid is used as the catalyst is complicated, indicating that the decomposition mechanism is complicated.

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

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.