Mathematical modeling and parameter estimation for 1,6-Hexanediol diacrylate photopolymerization with bifunctional initiator

A dynamic model is proposed for photopolymerization of 1,6-hexanediol diacrylate (HDDA) using bifunc-tional initiator bis-acylphosphine oxide (BAPO). The proposed model accounts for branching, backbiting and cyclization reactions, and for diffusion-dependent reaction rates during photopolymerization. The proposed model contains 40 adjustable kinetic and free-volume parameters. Experimental data available for parameter estimation are vinyl group conversions obtained using a variety of light intensities and exposure times, and monomer conversions for three experiments. Systematic parameter ranking and estimation is used to evaluate the influence of phenomena included in the model on the quality of the fit. Estimation and ranking results indicate that branching, backbiting, and cyclization reactions have important influences on conversion. Reactions involving two large molecules and propagation reactions become diffusion-dependent. Incorporating diffusion-dependent initiator efficiency results in improved model predictions.(c) 2022 Elsevier Ltd. All rights reserved.

Automated summary

A dynamic model is proposed for the photopolymerization of 1,6-hexanediol diacrylate (HDDA) using a bifunctional initiator bis-acylphosphine oxide (BAPO). The model takes into account branching, backbiting, cyclization reactions, and diffusion-dependent reaction rates. Parameter estimation and ranking analysis reveal that branching, backbiting, and cyclization reactions have significant influences on conversion. Reactions involving two large molecules and propagation reactions are diffusion-dependent. Incorporating diffusion-dependent initiator efficiency enhances the predictive capability of the model.