Degree of Cure of Epoxy/Acrylic Photopolymers: Characterization with Raman Spectroscopy and a Modified Phenomenological Model

Photopolymers possess unique capabilities, including the possibility for ambient temperature curing and the potential for control over where and when the polymer cures. These capabilities have given rise to a variety of products and processes including dental materials, contact lenses, coatings, microfluidic device fabrication, tissue engineering matrices, and photolithography. Recent developments in photopolymer technology include monomer mixtures and co-polymers. These applications are limited by our understanding of the photopolymerization process. A means for in situ monitoring of the cure process that would yield distinctive and attributive data would provide a better understanding of the curing process by enabling more accurate cure modeling of these materials. Such capabilities would allow optimal end-point predictions and would also enable process monitoring with instant parameter adjustment feedback. Tornado’s HyperFlux™ spectrometer was deployed for Raman analysis to determine a UV-curing process. The use of the Tornado Raman spectrometer enabled accurate diagnostic tracking of the cure cycle of the Accura® 60 photopolymer.