Predictive models for the photopolymerization of ceramic suspensions

The photopolymerization of suspensions of ceramic powders in monomer solutions is the fundamental step in several rapid prototyping forming techniques based on photocuring. Exposure to an UV dose of energy E causes the monomer to be polymerized to a certain cure depth, with the relation between cure depth and energy dose dependant on two properties of the photosuspension, the sensitivity and the critical energy dose. We present simple models for sensitivity in terms of the attenuation of the UV beam by absorption and scattering, and demonstrate the applicability of the model with experimental data for a UV laser, UV lamps and direct spectrophotometry. We also present a model for the critical energy dose in terms of the relative number of photo-generated radicals and the concentration of inhibitors.